WorldWideScience

Sample records for aux rayonnements ionisants

  1. Calculs de doses générées par les rayonnements ionisants principes et utilitaires

    CERN Document Server

    Vivier, Alain

    2012-01-01

    Cet ouvrage s'adresse aux utilisateurs de sources de rayonnements ionisants : techniciens et ingénieurs ou personnes compétentes en radioprotection, médecins, chercheurs, concepteurs... Les contraintes croissantes liées à la radioprotection rendent indispensable l'utilisation de codes (ou programmes) de calculs pour évaluer les débits de dose générée par les sources de rayonnements ionisants. De nombreux codes existent mais ils sont souvent relativement complexes à mettre en oeuvre et restent réservés aux bureaux d'études. En outre, ces codes sont souvent des "boîtes noires " qui ne permettent pas de comprendre la physique sous-jacente. L'objectif de cet ouvrage est double. Exposer les principes physiques permettant de comprendre les phénomènes à l'oeuvre lorsque la matière est irradiée par des rayonnements ionisants. Il devient ainsi possible de développer un sens physique pour appréhender ces phénomènes, alors même que nos propres sens sont impuissants à en percevoir la cause et le...

  2. External dosimetry for ionising radiation. From the national standard to the users in radiotherapy and radiation protection; La dosimetrie externe des rayonnements ionisants de la reference nationale aux utilisateurs en radiotherapie et en radioprotection

    Energy Technology Data Exchange (ETDEWEB)

    Bordy, J.M

    2009-07-01

    This report presents a review of the external dosimetry of the ionising radiations for the protection of the human being. Looking at this topic, at first we are confronted with its diversity: the protection of the workers and the public against radiations, the medical exposures for radiotherapy, diagnosis and surgery, and the accidental situations. These aspects are often artificially separated so that the global comprehension becomes more difficult. We underline the points of convergence and the bonds which exist between the concepts of dosimetry adopted to deal with its different aspects. It also appeared useful to avoid proposing a dictionary of definitions copied in the reports of the international commissions, and adopting the formalism of the ICRU reports. This is why the definitions, when they are essential, are put in appendix. This text presents the reasons which led to the adoption of the system of quantity used today for the external dosimetry of the ionising radiations. After an introduction dealing with the general principle, the first chapter deals with the 'physical' quantities and the methods used for the determination of the national references. The second chapter, through the protection against radiation of the workers and the public, describes the bonds between the measurable 'operational' quantities and the non measurable 'protections' quantities which allow establishing the radiation protection limits and check that they are respected. The third chapter deals with the difficulties encountered for the measurements in area and personal dosimetry. The fourth chapter deals with the specificities of the medical exposures with the 'practical' quantities, the principle of optimisation and how radiotherapy is implemented. The fifth chapter briefly describes the case of the concerted exposures and of the accident. In conclusion, we analyse the needs and some potential new avenues of work for the metrology of the

  3. Les neuropeptides gastro-intestinaux cibles des effets des rayonnements ionisants : altérations fonctionnelles

    Science.gov (United States)

    Linard, C.; Esposito, V.; Wysocki, J.; Griffiths, N. M.

    1998-04-01

    The symptoms associated with exposure to ionizing radiation are nausea, vomiting, diarrhoea. The response of the gut is complex involving modifications of motility and fluid and electrolyte transport. Gastrointestinal regulatory peptides have an important role in these functions. This study showed that radiation-induced tissue variations of neuropeptides have some repercussions on intestinal biological activity of these peptides soon after irradiation. In addition such modifications are also seen a few years after irradiation. Les symptômes associés à l'exposition aux rayonnements ionisants sont des nausées, vomissements et diarrhées. La réponse du système digestif est complexe, impliquant des modifications de la motilité et du transport d'eau et d'électrolytes. les neuropeptides gastro-intestinaux ont un rôle important dans ces fonctions. Cette étude montre que les variations tissulaires de ces neuropeptides induites par l'irradiation ont des répercussions sur l'activité biologique intestinale pour des temps précoces mais que ces perturbations sont encore visibles quelques années après l'irradiation.

  4. Effect of ionizing radiation on cardiovascular system; Les effets des rayonnements ionisants sur le systeme cardiovasculaire

    Energy Technology Data Exchange (ETDEWEB)

    Milliat, F.; Benderitter, M.; Gaugler, M.H. [Institut de radioprotection et de surete nucleaire, DRPH, SRBE, Laboratoire de radiopathologie et de therapies experimentales (LRTE), Fontenay-aux-Roses (France)

    2011-07-01

    Radiotherapy treatment for cancer of the chest, mediastinal area or the neck area is associated with increased risk of cardiovascular disease. With the increasing number of cancer patients and the increased treatment efficiency, the number of cancer survivors is increasing exponentially. The cancer survivors live longer and their long-term follow-up must be considered. The cardiovascular toxicity is mainly associated with the treatment of breast cancer, Hodgkin's lymphoma and head and neck cancer. Radiation-induced cardiovascular effects are insidious and chronic. Their occurrence is linked to numerous factors including the age of the patient at the beginning of the radiotherapy schedule, the number of years following radiotherapy, the doses (and volume) to the heart and the large vessels (coronary and carotid arteries), and the association with the traditional cardiovascular risk factors. Pathophysiological mechanisms remain unclear and, even if similarities with age-related atherosclerosis were established, the specificities of the radiation-induced atherosclerosis for high doses remain to be discovered. For low/moderate doses of ionising radiation, recent epidemiological studies provide evidence of increased risk of cardiovascular pathologies. A better knowledge of the mechanisms associated with the radiation-induced cardiovascular pathologies and the more precise identification of the populations at risk in the future should allow a more effective care of these patients with cardiovascular risk. (authors)

  5. The accidental exposure to ionizing radiations; L'exposition accidentelle aux rayonnements ionisants

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    This article is divided in three parts, the first one gives the radioactivity sources, the doses and the effects, the second part is devoted to the medical exposures, the third part concerns the accidents and the biological effects of an irradiation the different syndromes ( the acute whole-body irradiation syndrome, the localized irradiation syndrome, the inflammatory syndrome, hematopoietic syndrome,neuro-vascular syndrome) are detailed. (N.C.)

  6. Pregnancy and exposure to ionizing radiations; Femme enceinte et exposition aux rayonnements ionisants

    Energy Technology Data Exchange (ETDEWEB)

    Topsoba, T.L. [Ouagadougou-Burkina Faso Univ., Lab. de Biophysique UFR/SDS (Burkina Faso); Tapsoba, T.L.; Cisse, R.; Lougue Sorgho, L.C.; Bamouni, Y.A. [Centre Hospitalier Universitaire Yo, Service de Radiologie et d' Imagerie Medicale (Burkina Faso); Gassama Seck, S. [Faculte de Medecine - UCAD, Dakar (Senegal)

    2006-06-15

    The sensitivity of the embryo and foetus varies during pregnancy. Recent studies confirm that the principal damage is mental retardation. It is generally admitted that the risk is negligible for a dose < 100 milli-sieverts (mSv). A possible termination of pregnancy will be considered for an exposure > 200 mSv.The objective of this work is to provide precise information on the various risks related to the irradiation for the foetus, according to the age of gestation and delivered dose, and the action to be taken in case of accidental irradiation. The medical use of ionizing radiation in pregnant women can only be considered within the framework of precise information. (author)

  7. Thermoluminescent properties of CVD diamond: applications to ionising radiation dosimetry; Proprietes thermoluminescentes du diamant CVD: applications a la dosimetrie des rayonnements ionisants

    Energy Technology Data Exchange (ETDEWEB)

    Petitfils, A

    2007-09-15

    Remarkable properties of synthetic diamond (human soft tissue equivalence, chemical stability, non-toxicity) make this material suitable for medical application as thermoluminescent dosimeter (TLD). This work highlights the interest of this material as radiotherapy TLD. In the first stage of this work, we looked after thermoluminescent (TL) and dosimetric properties of polycrystalline diamond made by Chemically Vapor Deposited (CVD) synthesis. Dosimetric characteristics are satisfactory as TLD for medical application. Luminescence thermal quenching on diamond has been investigated. This phenomenon leads to a decrease of dosimetric TL peak sensitivity when the heating rate increases. The second part of this work analyses the use of synthetic diamond as TLD in radiotherapy. Dose profiles, depth dose distributions and the cartography of an electron beam obtained with our samples are in very good agreement with results from an ionisation chamber. It is clearly shown that CVD) diamond is of interest to check beams of treatment accelerators. The use of these samples in a control of treatment with Intensity Modulated Radiation Therapy underlines good response of synthetic diamond in high dose gradient areas. These results indicate that CVD diamond is a promising material for radiotherapy dosimetry. (author)

  8. Accord entre l'Organisation Européenne pour la Recherche Nucléaire, le Conseil Fédéral Suisse et le Gouvernement de la République Française relatif à la protection contre les rayonnements ionisants et à la sûreté des installations de l'Organisation Européenne pour la Recherche Nucléaire

    CERN Document Server

    2010-01-01

    Accord entre l'Organisation Européenne pour la Recherche Nucléaire, le Conseil Fédéral Suisse et le Gouvernement de la République Française relatif à la protection contre les rayonnements ionisants et à la sûreté des installations de l'Organisation Européenne pour la Recherche Nucléaire

  9. Prevention of risks in relation with occupational exposure to ionizing radiation; Prevention des risques lies a l'exposition professionnelle aux rayonnements ionisants

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    After remind the base notions in the field of ionizing radiation, this file evaluates the situation on the natural and occupational exposures: modes, sources, and exposure level, risk for health. It presents the principles of prevention allowing in a professional area (out of nuclear industry) to reduce and control these exposures. Some practical cases illustrate the radiation protection approach. references are given: regulatory benchmarks, useful links, books to consult. (N.C.)

  10. The risk of low doses of ionising radiation and the linear no threshold relationship debate; La controverse sur les effets des faibles doses de rayonnements ionisants et la relation lineaire sans seuil

    Energy Technology Data Exchange (ETDEWEB)

    Tubiana, M. [Centre Antoine Beclere, Faculte de Medecine, 75 - Paris (France); Masse, R. [11 rue du Haras, Residence Le Boqueteau, Acacias 2, 91 - Saint-Michel-sur-Orge (France); Vathaire, F. de [Institut Gustave Roussy, INSERM U 605., 94 - Villejuif (France); Averbeck, D. [Institut Curie, Section de Recherche, Lab. Raymond Latarjet, UMR2027 du CNRS, Centre Universitaire d' Orsay, 91 - Orsay (France); Aurengo, A. [Hopital Pitie-Salpetriere, Service Medecine Nucleaire, 75 - Paris (France)

    2007-04-15

    The ICRP and the B.E.I.R. VII reports recommend a linear no threshold (L.N.T.) relationship for the estimation of cancer excess risk induced by ionising radiations (IR), but the 2005 report of Medicine and Science French Academies concludes that it leads to overestimate of risk for low and very low doses. The bases of L.N.T. are challenged by recent biological and animal experimental studies which show that the defence against IR involves the cell microenvironment and the immunologic system. The defence mechanisms against low doses are different and comparatively more effective than for high doses. Cell death is predominant against low doses. DNA repairing is activated against high doses, in order to preserve tissue functions. These mechanisms provide for multicellular organisms an effective and low cost defence system. The differences between low and high doses defence mechanisms are obvious for alpha emitters which show several greys threshold effects. These differences result in an impairment of epidemiological studies which, for statistical power purpose, amalgamate high and low doses exposure data, since it would imply that cancer IR induction and defence mechanisms are similar in both cases. Low IR dose risk estimates should rely on specific epidemiological studies restricted to low dose exposures and taking precisely into account potential confounding factors. The preliminary synthesis of cohort studies for which low dose data (< 100 mSv) were available show no significant risk excess, neither for solid cancer nor for leukemias. (authors)

  11. Design and test of a scintillation dosimeter for dosimetry measurements of high energy radiotherapy beams; Conception et realisation d'un dosimetre a scintillation adapte a la dosimetrie de faisceaux de rayonnements ionisants en faisceaux de rayonnements ionisants en radiotherapie

    Energy Technology Data Exchange (ETDEWEB)

    Fontbonne, J.M

    2002-12-01

    This work describes the design and evaluation of the performances of a scintillation dosimeter developed for the dosimetry of radiation beams used in radiotherapy. The dosimeter consists in a small plastic scintillator producing light which is guided by means of a plastic optical fiber towards photodetectors. In addition to scintillation, high energy ionizing radiations produce Cerenkov light both in the scintillator and the optical fiber. Based on a wavelength analysis, we have developed a deconvolution technique to measure the scintillation light in the presence of Cerenkov light. We stress the advantages that are anticipated from plastic scintillator, in particular concerning tissue or water equivalence (mass stopping power, mass attenuation or mass energy absorption coefficients). We show that detectors based on this material have better characteristics than conventional dosimeters such as ionisation chambers or silicon detectors. The deconvolution technique is exposed, as well as the calibration procedure using an ionisation chamber. We have studied the uncertainty of our dosimeter. The electronics noise, the fiber transmission, the deconvolution technique and the calibration errors give an overall combined experimental uncertainty of about 0,5%. The absolute response of the dosimeter is studied by means of depth dose measurements. We show that absolute uncertainty with photons or electrons beams with energies ranging from 4 MeV to 25 MeV is less than {+-} 1 %. Last, at variance with other devices, our scintillation dosimeter does not need dose correction with depth. (author)

  12. Collection efficiency of charges in ionization chambers in presence of constant or variable radiation intensity; Efficacite de la collection des charges dans les chambres d'ionisation en presence d'une intensite de rayonnement ionisant constante ou variable

    Energy Technology Data Exchange (ETDEWEB)

    Decuyper, J. [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1970-07-01

    The theoretical and experimental study of the collection of carriers built up by ionization in standard chambers, is made by varying the value of different acting parameters. In the presence of constant ionization intensity and under a D.C. and A.C. voltage, the effect of geometry, recombination, diffusion and attachment is analyzed. The compensation of thermal neutron D.C. chambers is equally considered. Under a time dependent ionization intensity and D.C. voltage, is then studied the effect of recombination on current response, and on the collection efficiency of all formed charges. (author) [French] L'etude theorique et experimentale de la collection des porteurs crees par ionisation dans les chambres couramment utilisees est entreprise en fonction de la valeur des differents parametres agissants. En presence d'une ionisation constante et sous une tension d'alimentation d'abord continue puis alternative, on analyse l'influence de la geometrie, de la recombinaison, de la diffusion et de l'attachement. La compensation des chambres a courant continu de mesure neutronique est egalement examinee. Ensuite, sous une intensite d'ionisation variable dans le temps et en alimentation continue, on etudie l'effet de la recombinaison sur la reponse en courant et sur l'efficacite de la collection de la charge totale liberee. (auteur)

  13. Realisation of dosimetric studies for workplaces with a risk of exposure to ionizing radiations (version 2). Practical guide; Realisation des etudes dosimetriques de poste de travail presentant un risque d'exposition aux rayonnements ionisants (version 2). Guide pratique

    Energy Technology Data Exchange (ETDEWEB)

    Donadille, L.; Rehel, J.L.; Deligne, J.M.; Queinnec, F.; Aubert, B.; Bottollier-Depois, J.F.; Clairand, I.; Jourdain, J.R.; Rannou, A.

    2010-07-01

    This guide proposes a methodological approach to help carry out dosimetric workplace studies complying with the french regulation, and necessary to identify risks of radiological exposure, optimize radiation protection, classify the workers into different categories and the workplaces into different areas. Additional information is provided relating the main objectives of a workplace study, the French regulatory context, main sources and pathways of exposure to ionizing radiation. Radiation protection and operational quantities are reminded. Recommendations about the selection and use of detectors and about the implementation of calculation methods are also provided. The general methodological approach is applied and developed into 'workplace sheets', each one devoted to a particular type of workplace. (authors)

  14. Epidemiological studies and ionizing radiations; Etudes epidemiologiques et rayonnements ionisants

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-01

    After some generalities on epidemiological studies, this report presents the current status of knowledge and researches in three peculiar domains: leukaemia for young people living around nuclear power stations, pathologies in workers of the nuclear sector, and health condition (incidence of cancers) of populations living around nuclear power stations

  15. The non ionizing radiations; Les rayonnements non ionisants

    Energy Technology Data Exchange (ETDEWEB)

    Vecchia, P. [Institut National de la Sante, Lab. de Physique, Rome (Italy); Souques, M. [Electricite de France (EDF), Service des Etudes Medicales, 75 - Paris (France); Lambrozo, J. [EDF/GDF, Service des Etudes Medicales, 75 - Paris (France)] [and others

    2003-07-01

    The biological effects of non ionizing radiations are studied in this part. The magnetic fields and the cardiac implants, melatonin secretion among the electricians exposed to magnetic fields of 50 hz, the effects of electromagnetic fields in professional medium, evaluation of the effect of an exposure to a signal of a mobile phone (GSM 900) on the skin are the different subjects discussed. (N.C.)

  16. Epidemiology and ionizing radiations; Epidemiologie et rayonnements ionisants

    Energy Technology Data Exchange (ETDEWEB)

    Bourguignon, M. [Direction generale de la surete nucleaire et de la radioprotection (DGSNR), 75 - Paris (France); Masse, R. [Academie des technologies, 75 - Paris (France); Slama, R.; Spira, A. [Inserm et Ined U569, Epidemiologie, Demographie et Sciences Sociales: Sante Reproductive, Sexualite et Infection a VIH, 94 - Le Kremlin-Bicetre (France); Timarche, M.; Laurier, D.; Billon, S.; Rogel, A.; Telle Lamberton, M.; Catelinois, O.; Thierry, I. [Institut de Radioprotection et de Surete Nucleaire (IRSN), 92 - Clamart (France); Grosche, B. [Bundesamt fuer Strahlenschutz, Neuherberg (Germany). Inst. fuer Strahlenhygiene; Hall, P. [Karolinska Inst., Dept. d' Epidemiologie Medicale, Stockholm (Sweden); Ron, E. [Institut national du cancer, Div. Epidemiologie du Cancer et Genetique (United States); Vathaire, F. de [INSERM XR 521, Institut Gustave Roussy, 94 - Villejuif (France); Cherie Challine, L.; Donadieu, J.; Pirard, Ph. [Institut de veille sanitaire (InVs), 94415 - Saint-Maurice (France); Bloch, J. [Direction generale de la sante, 75 - Paris (France); Setbon, M. [Centre National de la Recherche Scientifique (CNRS), 75 - Paris (France)

    2004-01-01

    The ionizing radiations have effects on living being. The determinist effects appear since a threshold of absorbed dose of radiation is reached. In return, the stochastic effects of ionizing radiations are these ones whom apparition cannot be described except in terms of probabilities. They are in one hand, cancers and leukemia, on the other hand, lesions of the genome potentially transmissible to the descendants. That is why epidemiology, defined by specialists as the science that studies the frequency and distribution of illness in time and space, the contribution of factors that determine this frequency and this distribution among human populations. This issue gathers and synthesizes the knowledge and examines the difficulties of methodologies. It allows to give its true place to epidemiology. (N.C.)

  17. Interpolation de niveaux d'exposition aux émissions radioélectriques in situ à l'aide de méthodes géostatistiques

    OpenAIRE

    Ould Isselmou, Yahya

    2007-01-01

    Les réglementations et normes radioélectriques précisent différentes valeurs limites d'exposition radioélectrique à ne pas dépasser. Les niveaux d'expositions constatés autour des antennes de radio et de télécommunications sont très en dessous des limites d'exposition recommandées par la commission de protection contre les rayonnements non-ionisants. Aujourd'hui, les personnes se trouvant à proximité des émetteurs radio ne cherchent plus simplement à vérifier la conformité aux normes. La dema...

  18. Appraisal of alternative skin model for the study of epidermal restoration following exposure to various environmental stress agents: ionising radiation and UV B; Evaluation d'un modele alternatif de peau dans l'etude de l'atteinte epidermique apres exposition a differents agents de stress environnementaux: rayonnements ionisants (RI) et ultra-violets B (UVB)

    Energy Technology Data Exchange (ETDEWEB)

    Isoir, M

    2006-06-15

    Human skin is a major target tissue for ionising radiation (IR) and UV B. We developed a skin explant model and used 2 types of keratinocytes to study survival and oxidative stress induced by these radiations. We examined oxidative damages by measuring R.O.S. produced and cellular anti-oxidant defenses induced. We observed into skin exposed to IR a modulation of genes expression implied in the control of oxidative stress, confirmed by the decrease of catalase, glutathione peroxidase and superoxide dismutase enzymatic activities. The imbalance observed between anti- and pro-apoptotic genes expression shows that keratinocytes apoptosis may be partly dependent on radio-induced R.O.S. production. We showed the difference of radiosensitivity between N.H.E.K. and Ha Ca.T., which may be linked to their differential oxidative responses. In addition, during re-epithelialising, we demonstrated that activated N.H.E.K. after IR express keratin 6, release pro-inflammatory cytokines and proliferate, without modification of their differentiation. Treatment of N.H.E.K. with geranyl geranylacetone (G.G.A.) has a beneficial effect on their radio-induced activation by increasing IL-1 release, their migration in scrapped area and their survival. G.G.A. has an anti apoptotic ability (induction of Hsp70- caspase-3 pathway) and migratory properties (P38/RhoA activation) on N.H.E.K., but after IR, only caspase-3 pathway is induced. This work thus contributes to the understanding of cutaneous damages after IR and G.G.A. mechanism of action which accelerates re-epithelialising. (author)

  19. Assessment of risks associated to ionizing radiations: lung cancers after domestic radon exposure and thyroid cancers after accidental exposure to radioactive iodines; Evaluation des risques associes aux rayonnements ionisants: cancers du poumon apres exposition domestique au radon et cancers de la thyroide apres exposition accidentelle aux iodes radioactifs

    Energy Technology Data Exchange (ETDEWEB)

    Catelinois, O

    2004-09-15

    The aim of this work is to develop a critical analysis of quantitative risk assessment in the field of ionizing radiation and to provide new estimates of attributable risks for particular situations of environmental exposure to ionizing radiation. This work is based on knowledge about dose-response relationships and ionizing radiation exposure of the general population. The work focuses on two different situations that both present an important interest for public health: lung cancer associated with domestic radon exposures (natural situation) and thyroid cancer associated with the Chernobyl accident fallout (accidental situation). The assessment of lung cancer risk associated with domestic radon exposure considers 10 dose-response relationships resulting from miner cohorts and case-control studies in the general population. A critical review of available data on smoking habits has been performed and allowed to consider the interactions between radon and tobacco. The exposure data come from measurements campaigns carried out since the beginning of the 1980 by the Institute for Radiation protection and Nuclear Safety and the Health General Directory in France. The French lung cancer mortality data are provided by the I.N.S.E.R.M.. Estimates of the number of attributable cancers are carried out for the whole country, stratified by 8 large regions (Z.E.A.T.) and by 96 departments for the year 1999 allowing to perform a sensibility analysis according to the geographical level of calculation. Uncertainties associated to risk coefficients and exposures have been quantified and it's impact on risk estimates is calculated. The estimated number of deaths attributable to domestic radon exposure ranges from 543 (90% uncertainty interval (U.I.): 75-1,097) to 3,108 (90% U.I.: 2,996-3,221). The corresponding risk fractions range from 2.2% (90% U.I.: 0.3%-4.4%) to 12.4% (90% U.I.: 11.9%-12.8%). The assessment of thyroid cancer risk in the most exposed area of France due to the Chernobyl nuclear power plant accident fallout, is based on the excess relative risk model published by E. Ron et al. in 1995. The target population is composed of all children younger than 15 years and living in the eastern part of France at the time of the accident (26 April 1986). The incidence rates between 1978 and 1997 are analysed and forecasted up to 2007 using age-period-cohort models. Thyroid doses are estimated from all available data about the contamination in France from the Chernobyl fallout/ The risks characterization is carried out by considering various scenarios on the projection of spontaneous incidence rates, the effectiveness of internal exposures compared to external ones and the levels of radioactive deposits. Uncertainties to the risk coefficient, the expected spontaneous incidence rates and the thyroid dose are considered. The estimated number of thyroid cancer cases in excess between 1991 and 2007 for the target population ranges from 5 (90% U.I.: 1-15) to 63 (90% U.I. 12-180). In comparison, depending on the scenario of spontaneous rate projection, the number of spontaneous cancer cases should range from 894 (90% U.I.: 869-920) to 1,716 (90% U.I.:1,691-1,741) between 1991 and 2007. The results show that the thyroid cancer incident rate increase observed in France during last 20 years cannot be explained by the Chernobyl fallout. The work provides an adaptation of the classical risk assessment method integrating each of its step such as a discussion about the choice of the dose-response relationship. The data analysis considers the interaction between ionizing radiation and other risk factors, a spontaneous incidence rate projection and a quantification of uncertainties. This work provides new results showing the importance of the choice of the dose-response relationship, of the consideration of the spontaneous incidence trend and of the quantification of uncertainties in risk assessment. In conclusion, this work provides new knowledge for public health by the analysis of enlarged epidemiological data. (author)

  20. Order of the 30 December 2004 relative to the individual sheet of medical follow-up and to the individual information concerning the dosimetry of workers exposed to ionizing radiations; Arrete du 30 decembre 2004 relatif a la carte individuelle de suivi medical et aux informations individuelles de dosimetrie des travailleurs exposes aux rayonnements ionisants

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-12-15

    This order concerns the content and the modalities of grant of the individual sheet of medical follow-up, the collect and the centralization of dosimetry individual information by the Institute of Radiation Protection and Safety (IRSN), and the access to individual results of external and internal dosimetry. (A.L.B.)

  1. Decree of the 18. may 2004 relative to the training program bearing on the radiation protection of patients exposed to ionizing radiation; Arrete du 18 mai 2004 relatif aux programmes de formation portant sur la radioprotection des patients exposes aux rayonnements ionisants

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    This decree explains the contents of training relative to radiation protection for radiologists, doctors in nuclear medicine, doctors in radiotherapy, dental surgeons, doctors using ionizing radiations for diagnostic uses, for surgeons using ionizing radiations during surgery acts, for persons specialized in medical radiation physics, for manipulators in medical electro radiology. (N.C.)

  2. Surveillance of health care workers exposed to ionising radiation: Rimed pilot study

    International Nuclear Information System (INIS)

    The project so-called RIMED aimed to set up epidemiological surveillance of health care workers exposed to ionizing radiation. A pilot study was conducted in a sample of hospital personnel to examine the possibility of identifying exposed subjects in order to analyse mortality patterns according to occupational characteristics such as medical departments or occupations in a historical cohort. Seven hospitals participated in this pilot study. Health-care workers who had worn a dosimeter up to December 2003 were to be included in this cohort. The subjects' identification data were obtained from the SISERI (Systeme d'information de la surveillance de l'exposition aux rayonnements ionisants - Ionizing Radiation Exposure Monitoring Information System) database managed by the Institut de radioprotection et de surete nucleaire - Radiation Protection and Nuclear Safety Institute (IRSN). The SISERI system was in a 'pilot' phase in 2004. According to SISERI database, a total of 5126 subjects were found to have worn a dosimeter up to December 2003. The subjects' identification data were completed by the administrative services of the hospitals and occupational physicians searched for subjects' occupational data. Information required for the vital status search was satisfactorily completed only for 38% of the cohort subjects. This pilot study showed that obtaining data from SISERI database completed by hospital administrative data in 2004 led to a database of insufficient quality for epidemiological surveillance. The Institut de veille sanitaire (French Institute of Public Health Surveillance) recommends that transmission by the employers of some specific personal or occupational data of the exposed subjects should be made compulsory. In this way, SISERI system should be able to constitute any database with required quality for epidemiological surveillance of ionizing radiation exposed subjects. (authors)

  3. Radioprotection rayonnements, dosimétrie, protection

    CERN Document Server

    Marey, Gérard

    2014-01-01

    Pour tous les travailleurs du nucléaire comme pour les étudiants des licences professionnelles et des BTS Environnement nucléaire et BTS radioprotection, l'ouvrage rassemble de façon progressive, claire et précise toutes les informations scientifiques et pratiques qui leur sont indispensables. Une première partie résume les données de base relatives à la structure de la matière, la stabilité des noyaux, les différents rayonnements, leur énergie et la décroissance radioactive. La deuxième partie constitue une approche progressive de la radioprotection s'appuyant sur l'influence des rayonnement sur la matière pour définir les notions de dose et aborder le dimensionnement des protections biologiques et des éléments de ventilation. Enfin, la dernière partie traite de la mise en oeuvre pratique de la radioprotection sur le terrain et de la gestion des déchets nucléaires en application de la technologie actuelle, de la réglementation et des directives imposées par l'exploitant qu'est EDF. De...

  4. Contribution to the study and use of ionisation chambers for nuclear reactor control (1965); Contribution a l'etude et a l'utilisation des chambres d'ionisation pour le controle des reacteurs nucleaires (1965)

    Energy Technology Data Exchange (ETDEWEB)

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

    1961-02-15

    high-power reactors. (author) [French] Les chambres d'ionisation sont actuellement les detecteurs les mieux adaptes au controle des reacteurs nucleaires par des mesures neutroniques. Nous avons cru bon de rappeler quelques generalites concernant la dynamique des reacteurs, les differents procedes de detection des neutrons, le fonctionnement des chambres d'ionisation et les methodes de mesure utilisees. Notre contribution aux techniques de controle des reacteurs consiste d'une part en une tentative de synthese des facteurs intervenant dans le fonctionnement des chambres d'ionisation, l'etude de ces facteurs, et d'autre part l'elaboration de chambres d'ionisation a fission et a bore permettant de suivre la marche d'un reacteur du demarrage jusqu'a la puissance maximale. Dans le domaine des chambres a fission, nous avons en particulier ameliore les techniques de depot d'oxyde d'uranium sur l'aluminium et realise la mise au point de depots par electrolyse sur d'autres metaux: acier inoxydable, cuivre, molybdene, nickel, tantale, titane, kovar, tungstene et beryllium. Nous avons elabore plusieurs types de chambres a fission servant au demarrage des reacteurs: un type de performances moyennes actuellement utilise dans les piles francaises un type a haute sensibilite un type a haute temperature qui a fonctionne jusqu'a 600 deg. C. En ce qui concerne les chambres a bore, nous avons etudie les perturbations apportees dans les mesures par l'exposition des chambres a d'importants flux de neutrons et a un rayonnement {gamma} intense. Cette exposition produit une modification des proprietes des materiaux constitutifs et la production dans les chambres d'un bruit de fond qui peut gener considerablement les mesures neutroniques. Nous avons montre que la technique de compensation permettait de limiter l'importance de ce bruit de fond et d'augmenter ainsi la plage de fonctionnement des

  5. Preparation and characterization of a ferrimagnetic amorphous alloy of GdCo entering the design of magnetic tunnel junctions: ionizing radiations hardness of magnetic tunnel junctions; preparation et caracterisation d'un alliage amorphe ferrimagnetique de GdCo entrant dans la conception de jonctions tunnel magnetiques. Resistance des jonctions tunnel magnetiques aux rayonnements ionisants

    Energy Technology Data Exchange (ETDEWEB)

    Conraux, Y

    2005-10-15

    The magnetic random access memories (MRAM) are on the way to supplant the other forms of random access memories using the states of electric charge, and this thanks to their many technical advantages: not-volatility, speed, low consumption power, robustness. Also, the MRAM are alleged insensitive with the ionizing radiations, which was not checked in experiments until now. The current architecture of the MRAM is based on the use of magnetic tunnel junctions (MTJ). These MRAM can present an important disadvantage, because they are likely of present errors of addressing, in particular when integration (density of memory cells) is increasingly thorough. The work undertaken during this thesis relates to these two points: - to check the functional reliability of the MRAM containing JTM exposed to high energy ionizing radiations; - to study a ferrimagnetic amorphous alloy, GdCo, likely to enter the composition of JTM and allowing to free from the possible errors of addressing by a process of thermal inhibition of the memory cells. This work of thesis showed that the MRAM containing JTM preserve their functional properties fully when they are subjected to intense ionizing radiations, and that GdCo is a very interesting material from the point of view of the solid state physics and magnetism, that its physical properties are very promising as for its applications, and that its integration in a JTM still claims technological developments. (author)

  6. Physiological and molecular studies of the resistance to ionizing radiations of hyper-thermophilic archaea isolated from deep ocean hydrothermal sources; Etudes physiologiques et moleculaires de la resistance aux rayonnements ionisants d'archaea hyperthermophiles isolees de sources hydrothermales oceaniques profondes

    Energy Technology Data Exchange (ETDEWEB)

    Jolivet, E

    2002-10-15

    In this study, we have first tested in vivo the effect of gamma irradiation on Pyrococcus abyssi, a hyper-thermophilic archaeon, isolated from a deep-sea hydrothermal vent. We have shown that this strain was as radioresistant as P. furiosus but less than Deinococcus radiodurans. The rates of double stranded breaks provoked into DNA following irradiation were monitored by the pulsed-field gel electrophoresis technique (P.F.G.E.) with P. abyssi, P. furiosus, D. radiodurans and Escherichia coli. Results clearly showed that all these rates were similar suggesting that no specific DNA protection system exits in Pyrococcus species. The growth of P. abyssi was efficiently recovered within two hours following the exposure to 2.5 kGy of gamma irradiation. As revealed by P.F.G.E., genomic DNA of P. abyssi totally fragmented after irradiation was efficiently restored within two hours presumably by inter chromosomal homologous recombination. The DNA replication in P. abyssi cells following irradiation at 2.5 kGy was blocked for 90 minutes that corresponds to the decay for repairing damaged DNA. Moreover, following irradiation P. abyssi actively expulse damaged DNA material before DNA replication resumes, preventing the amplification of genetic mutations. We have also showed that at least a subset cf P. abyssi DNA repair and replication proteins, such as RadA, RPA-41 and RFC-S. were constitutively expressed in chromatin bound forms in stationary phase cells. Our results were in agreement with the view that P. abyssi contains a very efficient DNA repair system, which is continuously ready to counteract the DNA damaged caused by the high temperature and/or ionizing radiation. For the first time, three novel hyper-thermophilic archaea species from deep-sea hydrothermal vents more radioresistant than P. abyssi were isolated and characterized, after 'y-irradiation exposures of some enrichment cultures. Thermococcus marinus, Thermococcus radiophilus and Thermococcus gammafolerans were able to survive to elevated doses of {gamma}-irradiation from around 20 to 40 kGy which make them the most radioresistant hyper-thermophilic archaea isolated so far. Likewise, no specific DNA protection system was shown and their chromosomal damaged DNA following exposure to 2.5 kGy of {gamma}-irradiation were fully restored within two hours incubation under optimal growth conditions. (author)

  7. Exposure to ionizing radiations having a medical origin. Propositions for the implementation and the development of epidemiology surveillance activities in general population; Exposition aux rayonnements ionisants d'origine medicale. Propositions pour la mise en place et le developpement d'activites de surveillance epidemiologique en population generale

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-09-01

    This report gives propositions relative to the implementation and the development of epidemiology surveillance activities in general population in relation with medical exposure to ionizing radiations. It is intended for the General Direction of Health and General Direction of Nuclear Safety and Radiation Protection. These propositions have been elaborated by a work group coordinated and run by InVS and gathering the following organisms: French Agency of sanitary safety of health products (A.F.S.S.A.P.S.), Center of Quality Assurance of technological applications in the area of health (C.A.A.T.S.), Direction of Hospitals and Care organization (D.H.O.S.), General Direction of Health (D.G.S.), General Direction of Nuclear Safety and Radiation Protection (D.G.S.N.R.), National Federation of radiologists physicists (F.N.M.R.), institute of Radiation Protection and Nuclear Safety (I.R.S.N.), INSERM 'epidemiology of cancers', French Society of Biology and Nuclear Medicine (S.F.B.M.N.), French Society of Medical Physics (S.F.P.M.), French Society of Radiology (S.F.R.). (N.C.)

  8. Study of consequences of a ionizing radiation exposure on the health of persons having stay at the Marie Curie school of Nogent-sur-Marne (Val-de-Marne); Etude des consequences d'une exposition aux rayonnements ionisants sur la sante des personnes ayant sejourne a l'ecole Marie Curie de Nogent-sur-Marne (Val-de-Marne)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-03-01

    This study follows two other ones about the same subject. No one could bring elements to the question of the exposure impact on the population having stayed in the school. The old pupils and personnel have been exposed to radiation doses higher to the limit values of public exposure especially before 1987. The scientific knowledge suggest that the eventual sanitary consequences are in the area of low risks. The lack of exhaustiveness in the inquiry realisation and the lack of statistical power did not allow to measure the sanitary impact of ionizing radiation exposure among the former pupils of the Marie Curie school of Nogent sur Marne. (N.C.)

  9. Consideration of measurement errors in the analysis of the risk related to the exposure to ionising radiation in an occupational cohort: application to the French cohort of uranium miners; Prise en compte des erreurs de mesure dans l'analyse du risque associe a l'exposition aux rayonnements ionisants dans une cohorte professionnelle: application a la cohorte francaise des mineurs d'uranium

    Energy Technology Data Exchange (ETDEWEB)

    Allodji, Rodrigue Setcheou

    2011-12-09

    In epidemiological studies, measurement errors in exposure can substantially bias the estimation of the risk associated to exposure. A broad variety of methods for measurement error correction has been developed, but they have been rarely applied in practice, probably because their ability to correct measurement error effects and their implementation are poorly understood. Another important reason is that many of the proposed correction methods require to know measurement errors characteristics (size, nature, structure and distribution). The aim of this thesis is to take into account measurement error in the analysis of risk of lung cancer death associated to radon exposure based on the French cohort of uranium miners. The mains stages were (1) to assess the characteristics (size, nature, structure and distribution) of measurement error in the French uranium miners cohort, (2) to investigate the impact of measurement error in radon exposure on the estimated excess relative risk (ERR) of lung cancer death associated to radon exposure, and (3) to compare the performance of methods for correction of these measurement error effects. The French cohort of uranium miners includes more than 5000 miners chronically exposed to radon with a follow-up duration of 30 years. Measurement errors have been characterized taking into account the evolution of uranium extraction methods and of radiation protection measures over time. A simulation study based on the French cohort of uranium miners has been carried out to investigate the effects of these measurement errors on the estimated ERR and to assess the performance of different methods for correcting these effects. Measurement error associated to radon exposure decreased over time, from more than 45% in the early 70's to about 10% in the late 80's. Its nature also changed over time from mostly Berkson to classical type from 1983. Simulation results showed that measurement error leads to an attenuation of the ERR towards the null, with substantial bias on ERR estimates in the order of 60%. All three error-correction methods allowed a noticeable but partial reduction of the attenuation bias. An advantage was observed for the simulation-extrapolation method (SIMEX) in our context, but the performance of the three correction methods highly depended on the accurate determination of the characteristics of measurement error. This work illustrates the importance of measurement error correction in order to obtain reliable estimates of the exposure-risk relationship between radon and lung cancer. Corrected risk estimates should prove of great interest in the elaboration of protection policies against radon in radioprotection and in public health. (author)

  10. Une méthode pour estimer l’interception du rayonnement par un couvert bas : application au colza avant montaison

    Directory of Open Access Journals (Sweden)

    Denoroy Pascal

    2002-01-01

    Full Text Available Dans les modèles de simulation du fonctionnement des cultures, l’interception du rayonnement est une variable cruciale pour la prévision de la productivité en biomasse. D’autre part, la connaissance de l’interception du rayonnement par une culture permet de mieux analyser la réponse à un traitement en autorisant la distinction entre les effets morphogénétique et physiologique du traitement. Par exemple, dans l’étude de la fertilisation azotée du colza [1] on a pu faire la part de l’effet morphogénétique (accroissement de l’indice foliaire, donc de l’interception et de l’amélioration de la conversion photosynthétique du rayonnement absorbé. Dans un cas comme dans l’autre, une estimation correcte de l’interception du rayonnement est essentielle. Très souvent, un formalisme dérivé de la loi de Beer-Lambert est utilisé pour quantifier la part interceptée du rayonnement : PARi = epsiloni PAR (1 et epsiloni = 1 - e- k.IF (2, PAR représentant le rayonnement photosynthétiquement actif incident (exprimé en Joules ou en moles de photons, PARi la part de ce dernier interceptée par le couvert, epsiloni le coefficient (sans dimension d’interception, IF l’indice foliaire et k le coefficient d’extinction du rayonnement. Un formalisme un peu plus complexe doit être utilisé si on veut considérer le rayonnement absorbé [1, 2]. Pour des cultures couvrantes, la sensibilité de ces modèles à la valeur de k est faible pour les IF élevés, c’est pourquoi ces modèles sont souvent utilisés avec succès. Mais aux faibles IF, les modèles sont sensibles à k, d’où l’importance de l’estimation de ce paramètre pour les cultures présentant une longue période de faible couverture du sol, tel le colza peu fertilisé en phase hivernale. De plus, pour les cultures discontinues, c’est-à-dire présentant des zones où le sol n’est pas du tout couvert par la végétation, comme les inter-rangs, on doit

  11. Effects of low doses of ionizing radiation; Effets des faibles doses de rayonnements ionisants

    Energy Technology Data Exchange (ETDEWEB)

    Masse, R. [Office de Protection contre les Rayonnements Ionisants, 78 - le Vesinet (France)

    2006-07-01

    Several groups of human have been irradiated by accidental or medical exposure, if no gene defect has been associated to these exposures, some radioinduced cancers interesting several organs are observed among persons exposed over 100 to 200 mSv delivered at high dose rate. Numerous steps are now identified between the initial energy deposit in tissue and the aberrations of cell that lead to tumors but the sequence of events and the specific character of some of them are the subject of controversy. The stake of this controversy is the risk assessment. From the hypothesis called linear relationship without threshold is developed an approach that leads to predict cancers at any tiny dose without real scientific foundation. The nature and the intensity of biological effects depend on the quantity of energy absorbed in tissue and the modality of its distribution in space and time. The probability to reach a target (a gene) associated to the cancerating of tissue is directly proportional to the dose without any other threshold than the quantity of energy necessary to the effect, its probability of effect can be a more complex function and depends on the quality of the damage produced as well as the ability of the cell to repair the damage. These two parameters are influenced by the concentration of initial injuries in the target so by the quality of radiation and by the dose rate. The mechanisms of defence explain the low efficiency of radiation as carcinogen and then the linearity of effects in the area of low doses is certainly the least defensible scientific hypothesis for the prediction of the risks. (N.C.)

  12. About particular use of ionizing radiations; Des usages particuliers des rayonnements ionisants

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-02-01

    Different uses of ionizing radiations are reviewed: tracers techniques, nuclear gauges, dating by carbon 14, silica doping, use of gamma irradiation for the density measurement in civil engineering, use of a electron capture detector to study by gas chromatography chlorinated contaminants in environment, neutron activation as environmental gauge, analysis of lead in paint and pollutants in ground and dusts, help for work of art valuation by x spectrometry. (N.C.)

  13. Nuclear law: protection against ionizing radiations; Droit nucleaire: protection contre les rayonnements ionisants

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-15

    The object of this work is since its first edition in 1983 under the title 'Collection of nuclear activities legislation and regulation ' to realize an ordered collection of texts constituting the juridical and institutional frame of nuclear activities, gathering the legislative, regulatory and technical texts; the international, European and national texts. Aiming to include the whole of the atom applications, this collection tackles various themes, in ten chapters. The volume number three is constituted by the following chapter: Protection against ionizing radiations. (N.C.)

  14. Expansion des feuilles de tournesol en conditions environnementales fluctuantes : effets de la température, du rayonnement et du déficit hydrique

    Directory of Open Access Journals (Sweden)

    2000-03-01

    Full Text Available L’expansion et les divisions cellulaires dans les feuilles de tournesol ont été analysées dans des situations contrastées de température, de rayonnement et d’état hydrique du sol, en serre, au champ et en chambre de culture. Les résultats expérimentaux obtenus remettent en cause deux concepts utilisés dans le formalisme des modèles de simulation des cultures : – le premier est celui qui considère que l’expansion foliaire dépend du carbone disponible. Des déficits hydriques modérés et précoces réduisent la surface finale des feuilles de 40% sans affecter la photosynthèse nette. Ils se traduisent par des accumulations de sucres dans les feuilles en déficit hydrique; – le second est celui qui relie la vitesse absolue d’expansion un jour donné aux conditions environnementales le même jour. Des contraintes hydriques ou des réductions du rayonnement absorbé affectent la vitesse absolue d’expansion plusieurs jours après le rétablissement des conditions favorables. Dans le modèle que nous proposons, la considération de la vitesse relative d’expansion des feuilles plutôt que de la vitesse absolue permet de rendre compte des arrière-effets négatifs des contraintes sur la vitesse d’expansion des feuilles. La vitesse relative d’expansion à un moment donné est directement reliée aux conditions environnementales au même moment. Son expression en temps thermique permet de prendre en compte les effets de la température. Elle est réduite par un déficit hydrique et par une réduction du rayonnement absorbé. Dans ce modèle, les durées d’expansion et de divisions cellulaires dans les feuilles, exprimées en temps thermique, sont stables pour un rang de feuille donné dans une large gamme de rayonnement absorbé et d’état hydrique du sol.

  15. Food ionisation. Realities and perspectives

    International Nuclear Information System (INIS)

    The ionisation of food is a treatment using a certain type of energy. the radiations used in the industrial treatments are limited to three sources. The gamma radiations, the x radiations and the electrons beams emitted with accelerators. The physical treatments by ionizing radiations have for aim to cleanse and to increase the conservation time of food. Now, the applications in agriculture and food industry, are still marginal. The industrial using ionisation are these ones that did not find any alternative decontamination method. The barriers are more scientific or technical or economical than a question of regulation or behaviour. (N.C.)

  16. Biological effects of the ionizing radiation. Press breakfast; Effets biologiques des rayonnements ionisants. Petit dejeuner de presse

    Energy Technology Data Exchange (ETDEWEB)

    Flury-Herard, A. [CEA, Direction des Sciences du Vivant, DSV, 75 - Paris (France); Boiteux, S.; Dutrillaux, B. [CEA/Fontenay-aux-Roses, Direction des Sciences du Vivant, DSV, 92 (France); Toledano, M. [CEA Saclay, Direction des Sciences du Vivant, DSV, 91 - Gif-sur-Yvette (France)

    2000-06-01

    This document brings together the subjects discussed during the Press breakfast of 29 june 2000 on the biological effects of the ionizing radiations, with scientists of the CEA and the CNRS. It presents the research programs and provides inquiries on the NDA operating to introduce the NDA damages by ionizing radiations, the possible repairs and the repair efficiency facing the carcinogenesis. Those researches allow the scientists to define laws on radiation protection. (A.L.B.)

  17. Nuclear law: nuclear matter and ionizing radiation sources. Wastes; Droit nucleaire: matieres nucleaires et sources de rayonnements ionisants. Dechets

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-15

    The object of this work is since its first edition in 1983 under the title 'Collection of nuclear activities legislation and regulation ' to realize an ordered collection of texts constituting the juridical and institutional frame of nuclear activities, gathering the legislative, regulatory and technical texts; the international, European and national texts. Aiming to include the whole of the atom applications, this collection tackles various themes, in ten chapters.The volume number two includes the following chapters: nuclear matters and ionizing radiations sources; wastes. Previously edited by the Cea, that realizes it it is now published in the collection 'Legislation and regulation' of officials journals editions. (N.C.)

  18. The place of ionizing radiation in the cancer genesis; La place des rayonnements ionisants dans la genese des cancers

    Energy Technology Data Exchange (ETDEWEB)

    Simon, J. [Societe Francaise d' Energie Nucleaire, 75 - Paris (France)

    2009-12-15

    Two different fields are considered: the field of high radiation doses (over 1 Sv), the contribution of ionizing radiation in the carcinogenesis is doubtless and the linear dose-effect relationship is unshakable. but this high doses area is rare ( major accident of civil nuclear, radiotherapy, war with use of nuclear weapon) and escapes to usual standards. The field of low dose irradiation (inferior to 100 MSv) we cannot assure the absence of carcinogen risk of ionizing radiation. We can tell that this risk is very low, very inferior to 5% by sievert accepted by the ICRP in conformance with the precautionary principle. In any case, very inferior to the risk in relation with the big causes of cancer that are addiction to smoking, (30% of cancers), food (30% of cancers), chronic diseases (11% of cancers) and hormonal processes (10% of cancers). (N.C.)

  19. Health and biological effects of non-ionizing radiations; Effets biologiques et sanitaires des rayonnements non ionisants

    Energy Technology Data Exchange (ETDEWEB)

    De Seze, R.; Souques, M.; Aurengo, A.; Bach, V.; Burais, N.; Cesarini, J.P.; Cherin, A.; Decobert, V.; Dubois, G.; Hours, M.; Lagroye, I.; Leveque, Ph.; Libert, J.P.; Lombard, J.; Loos, N.; Mir, L.; Perrin, A.; Poulletier De Gannes, F.; Thuroczy, G.; Wiart, J.; Lehericy, St.; Pelletier, A.; Marc-Vergnes, J.P.; Douki, Th.; Guibal, F.; Tordjman, I.; Gaillot de Saintignon, J.; Collard, J.F.; Scoretti, R.; Magne, I.; Veyret, B.; Katrib, J.

    2011-07-01

    This document gathers the slides of the available presentations given during this conference day on the biological and health effects of non-ionizing radiations. Sixteen presentations out of 17 are assembled in the document and deal with: 1 - NMR: biological effects and implications of Directive 2004/40 on electromagnetic fields (S. Lehericy); 2 - impact of RF frequencies from mobile telephone antennas on body homeostasis (A. Pelletier); 3 - expression of stress markers in the brain and blood of rats exposed in-utero to a Wi-Fi signal (I. Lagroye); 4 - people exposure to electromagnetic waves: the challenge of variability and the contribution of statistics to dosimetry (J. Wiart); 5 - status of knowledge about electromagnetic fields hyper-sensitivity (J.P. Marc-Vergnes; 6 - geno-toxicity of UV radiation: respective impact of UVB and UVA (T. Douki); 7 - National day of prevention and screening for skin cancers (F. Guibal); 8 - UV tan devices: status of knowledge about cancer risks (I. Tordjman, and J. Gaillot de Saintignon); 9 - modulation of brain activity during a tapping task after exposure to a 3000 {mu}T magnetic field at 60 Hz (M. Souques and A. Legros); 10 - calculation of ELF electromagnetic fields in the human body by the finite elements method (R. Scoretti); 11 - French population exposure to the 50 Hz magnetic field (I. Magne); 12 - LF and static fields, new ICNIRP recommendations: what has changed, what remains (B. Veyret); 13 - risk assessment of low energy lighting systems - DELs and CFLs (J.P. Cesarini); 14 - biological effects to the rat of a chronic exposure to high power microwaves (R. De Seze); 15 - theoretical and experimental electromagnetic compatibility approaches of active medical implants in the 10-50 Hz frequency range: the case of implantable cardiac defibrillators (J. Katrib); French physicians and electromagnetic fields (M. Souques). (J.S.)

  20. Radiative effects of tropospheric ionisation

    Directory of Open Access Journals (Sweden)

    K. L. Aplin

    2003-06-01

    Full Text Available Despite the increasing evidence that cosmic ray variations may influence clouds and climate, there has been little discussion of the direct radiative effects of atmospheric ionisation. Laboratory experiments show that hydrated molecular cluster-ions, formed in the atmosphere by cosmic rays, absorb in the infra-red continuum at wavelengths of 9–12 μm. The tropospheric magnitude of this effect is estimated: transmittance anomalies from clear sky ion concentrations peak at ~2% at 10 km in the mid-latitudes. A simple isothermal clear sky atmospheric model suggests the integrated effect of the absorption is ~2 Wm−2. The effect appears detectable in existing surface data sets; surface micrometeorological data shows a significant anticorrelation between downwelling infra-red radiation and atmospheric cosmic ray ionisation. This is consistent with the infra-red attenuation observed in laboratory studies of cluster-ion absorption. If atmospheric ionisation from cosmic rays has universally direct radiative effects, then reinterpretation of satellite cloud data may be necessary.

  1. Measurement of the electronic density of ionised media by hyper frequency methods; Mesure de la densite electronique des milieux ionises par des methodes hyperfrequences

    Energy Technology Data Exchange (ETDEWEB)

    Consoli, T. [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1960-07-01

    Within the limits of the I.N.S.T.N. courses on plasmas, this analytical study summarizes the articles quoted in the references on hyper-frequency techniques for the measurement of electronic density of an ionised gas. It is neither exhaustive nor complete and further details may be obtained by referring to the works mentioned. The first part, devoted to the theoretical side, concert the propagation of electromagnetic waves ionised media and the excitation of stationary raves in electromagnetic cavities. The second part deals with the measurement techniques themselves. It includes those techniques which hare become classic, and also more recent ones being developed in various laboratories and in the Service of Applied Physics at Saclay. (author) [French] Dans le cadre des cours sur les plasmas a l'l.N.S.T. cette etude d'analyse resume les articles cites en bibliographie sur les techniques hyperfrequences pour la mesure de la densite electronique d'un gas ionise. Elle n'est ni exhaustive, ni complete. Pour plus de details on voudra bien se rapporter aux travaux mentionnes. La premiere partie consacree a des rappels theoriques, concerne la propagation des ondes electromagnetiques dans les milieux ionises et sur l'excitation d'ondes stationnaires dans les cavites electromagnetiques. La seconde se rapporte aux techniques de mesures proprement dites. On a fait figurer dans cette partie des techniques devenues classiques et celles plus recentes en cours d'etudes dans divers laboratoires et au Service de Physique Appliquee a SACLAY. (auteur)

  2. Radiations and medical practices. Index card 1- medical exposure to ionizing radiations: situation diagnosis. Index card 2 - regulation and patients radiation protection. Index card 3 - action of I.R.S.N. in support of patients radiation protection. Index card 4 - small typology of medical practice based on ionizing radiation. Index card 5 - radiation doses and their effects on health; Rayons et pratiques medicales. Fiche 1 - l'exposition medicale aux rayonnements ionisants: diagnostics de la situation. Fiche 2 - reglementation et radioprotection des patients. Fiches 3 - l'action de l'IRSN en faveur de la radioprotection des patients. Fiches 4 - petite typologie des pratiques medicales a base de rayonnements ionisants. Fiche 5 - les doses et leurs effets sur la sante

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    The diagnosis radiology, the nuclear medicine and radiotherapy have been developed in any medical specialty. The medical exposures to ionizing radiation are the first reason of exposure to artificial ionizing radiation for population. Progress have been made to reduce the radiation doses delivered to patients, thus, in Great Britain efforts have lead to a reduction of 30% of doses delivered to patients. (N.C.)

  3. Etude statistique du rayonnement solaire sur un plan incliné

    OpenAIRE

    MOUHOUS-CHAOUCHI, Samira

    2012-01-01

    Ce travail présente une étude statistique des valeurs des rayonnements Diffus et Global mesurées et calculées sur un plan incliné à la latitude du lieu à Bouzaréah (36.8°). Pour le calcul du rayonnement diffus sur plan incliné cinq modèles ont été choisis ; le modèle isotrope de la première génération, le modèle de Hay et le modèle de Reindl de la deuxième génération et le modèle de Gueymard et le modèle de Perez de la troisième génération. Les modèles sont évalués sur une base graphique et s...

  4. COMMANDE D’HELIOSTAT PLAN REFECHISSANT LE RAYONNEMENT SOLAIRE VERS UNE CIBLE FIXE

    OpenAIRE

    MIHOUB, Sofiane

    2010-01-01

    L’objectif de notre travail est de commander un héliostat plan, dédié à une centrale solaire à tour, réfléchissant le rayonnement solaire vers une cible fixe ( le récepteur) à l’aide d’un système de poursuite solaire à deux axes. Les centrales solaire à tour nécessitent un très fort ensoleillement et un faible taux d’humidité, pour cela on a commencé par étudier le gisement solaire du site choisi, celui de GHARDAIA , dans le sud de l’Algérie afin de connaitre son rayonnement solaire pendan...

  5. Effet des additifs sur la structure cristalline du polyéthylène à basse densité (PEBD irradiés par des rayonnements UV

    Directory of Open Access Journals (Sweden)

    Cheloufi T

    2014-04-01

    Full Text Available L’effet des rayons U V sur les propriétés physico-chimiques et mécaniques du polyéthylène à basse densité (PEBD et pigmenté avec des additifs dans différentes formulations ont été étudiées. Les échantillons ont été exposés au rayonnement U V émis par une lampe à xénon d’une puissance de 6000 W à une température de 46 °C pour différents temps. Un échantillon de référence a été pris pour la comparaison. A l’aide de la spectroscopie infrarouge FTIR et l’essai de traction, on a pu suivre les changements structuraux physico-chimiques et mécaniques. L’évolution des paramètres mécaniques (module d’élasticité, contrainte et allongement à la rupture ainsi que l’évolution des groupements carbonylés sous l’effet des radiations UV sont discutées. L’allongement à la rupture diminue avec le temps d’exposition pour la plupart des formulations étudiées, sauf la formulation F4 (anti-oxydant/stabilisant dont il y à une augmentation avec le temps. Par les RX, on a pu calculer le taux de cristallinité qui ont donné des valeurs élevées par rapport à d’autres ce qui est du probablement aux additifs ajoutés (chimassorb 81. Les résultats obtenus montrent que les additifs (stabilisants lumière et anti-oxydants avec des concentrations appropriées donnent des améliorations fiables concernant le comportement mécanique et les propriétés physico-chimiques des échantillons du PEBD exposés au rayonnement UV.

  6. Nucleation in an ultra low ionisation environment

    DEFF Research Database (Denmark)

    Enghoff, Martin Andreas Bødker

    the measurements to ionisation levels approximately 3 order of magnitudes lower than any earlier study. Getting this close to zero ionisation allows us to distinguish between the neutral and charged contribution better than previously. The effect is explored over a range of sulphuric acid concentrations.......In this work we have studied aerosol formation at ultra-low ionisation levels, using the existing deep underground science facility at Boulby mine, UK. At 1100 m depth, with a corresponding factor 106 reduction in cosmic ray muon flux, the Boulby facility is an ideal place to study the role of ions...

  7. Mesures d'ensoleillement : Publication No 17 : Rayonnement réfléchi et coefficient d'albédo

    OpenAIRE

    Ineichen, Pierre; Guisan, Olivier

    1988-01-01

    Une estimation correcte du rayonnement solaire incident sur un plan incliné d'orientation et d'inclinaison quelconques implique une connaissance du rayonnement en provenance du ciel et du rayonnement réfléchi par le sol. Diverses études [1,2] consacrées à la transposition du rayonnement solaire céleste ont été effectuées sur le plan international et ont abouti à la recommandation de l'utilisation du modèle de Perez [3,4] pour l'évaluation de la composante céleste du rayonnement diffus reçue s...

  8. Health Service use of ionising radiations: Guidance

    International Nuclear Information System (INIS)

    This booklet gives outline guidance on the use of ionising radiations in the Health Service in the United Kingdom. Extensive reference is made to documents where more detailed information may be found. The guidance covers general advice on the medical use of ionising radiations, statutory requirements, and guidance on selected Health Service issues such as patient identification procedures, information management systems, deviations from prescribed radiation dose, imaging and radiotherapy. (57 references) (U.K.)

  9. Comportement des pesticides ionisables dans les sols

    OpenAIRE

    Kah, Mélanie; Brown, Colin D.

    2007-01-01

    Ionisable pesticides can be partially ionised within the range of natural soil pH and this strongly influences their reactivity in soils. This group includes important, worldwide contaminants of groundwater and surface waters. It is essential that their specific behaviour is recognised within risk assessment procedures. Experiments were carried out with ten pesticides (six acids and four bases) and nine arable soils (range in pH, texture and organic matter content) to advance the understandin...

  10. Behaviour of circuits with respect to ionising radiations; Tenue des circuits aux radiations ionisantes

    Energy Technology Data Exchange (ETDEWEB)

    Boudenot, J.C. [Thomson-CSF, 75 - Paris (France)

    1999-11-01

    Electronic components with a greater integration of transistors, with an increase of surface and with reduced grid distances and operating voltages are more and more developing. These new technologies are more sensible to radiative environments which can lead to important disturbances: multiple upset, low level leakage current in MOS components etc.. The hardening techniques used so far must be adapted in order to take into account these new phenomena. This paper deals successively with: 1 - recall about radiations: interaction with matter (electrons, protons, heavy ions, photons, neutrons), effects to be considered (dose and dose rates, displacements, linear energy transfer and critical load); 2 - radiative environments: nuclear explosions, spatial environment (radiation belts, solar eruptions and wind, cosmic radiation), atmospheric environment, other environments (particle accelerators, robots in radiative environments, nuclear power plants, propulsion reactors, fusion devices, dismantling of nuclear facilities, industrial irradiations); 3 - radiative effects and technological hardening: cumulated dose (basic mechanisms, influence of radiation, polarization, dose rates, temperature, process, vulnerability of components), neutron fluence, heavy ions; 4 - protection means: components technology, circuits and systems (dose and dose rates, neutrons, heavy ions), hardening strategy; 5 - hardening validation: testing methods and procedures, nuclear hardening assurance (context, definition of needs, distribution of afterlife probabilities, design margins, components classification, repertory file), space hardening assurance (context, dose effects, direct and indirect heavy ion effects, assurance costs). (J.S.)

  11. Impact assessment of ionising radiation on wildlife

    International Nuclear Information System (INIS)

    This R and D project was commissioned by the Environment Agency and English Nature in January 2001 to provide up-to-date information on the impacts of ionising radiation on wildlife, upon which a robust assessment approach may be developed. This approach will also feed into the European Commission funded project 'Framework for Assessment of Environmental Impact' (FASSET), due to complete in October 2003. This report describes the behaviour and transport of radionuclides in the environment, considers the impact of ionising radiation on wildlife, and makes recommendations on an approach for the impact assessment of ionising radiation on wildlife for England and Wales. The assessment approach focuses on three ecosystems representative of those considered potentially most at risk from the impact of authorised radioactive discharges, namely a coastal grassland (terrestrial ecosystem); estuarine and freshwater ecosystems. The likely scale of the impact on wildlife is also assessed in light of a preliminary analysis based on this assessment approach. The aims of the report are: to summarise the latest research on the behaviour, transfer and impact of ionising radiation effects on wildlife; an outline and review of the relevant European and national legislation which has impacts on the requirements for assessments of the impact of ionising radiation on wildlife in the UK; to consider the role of regulatory bodies in assessing the impact of ionising radiation on wildlife with respect to England and Wales; to make recommendations on the relative biological effectiveness of different types of radiation with respect to wildlife; and to recommend an approach to assess the impacts to wildlife from ionising radiation from authorised discharges in England and Wales, with spreadsheets to support the methodology. The report demonstrates the behaviour and transfer of radionuclides in a number of different ecosystem types. Particular emphasis is placed on exposure pathways in those

  12. European Code against Cancer 4th Edition: Ionising and non-ionising radiation and cancer.

    Science.gov (United States)

    McColl, Neil; Auvinen, Anssi; Kesminiene, Ausrele; Espina, Carolina; Erdmann, Friederike; de Vries, Esther; Greinert, Rüdiger; Harrison, John; Schüz, Joachim

    2015-12-01

    Ionising radiation can transfer sufficient energy to ionise molecules, and this can lead to chemical changes, including DNA damage in cells. Key evidence for the carcinogenicity of ionising radiation comes from: follow-up studies of the survivors of the atomic bombings in Japan; other epidemiological studies of groups that have been exposed to radiation from medical, occupational or environmental sources; experimental animal studies; and studies of cellular responses to radiation. Considering exposure to environmental ionising radiation, inhalation of naturally occurring radon is the major source of radiation in the population - in doses orders of magnitude higher than those from nuclear power production or nuclear fallout. Indoor exposure to radon and its decay products is an important cause of lung cancer; radon may cause approximately one in ten lung cancers in Europe. Exposures to radon in buildings can be reduced via a three-step process of identifying those with potentially elevated radon levels, measuring radon levels, and reducing exposure by installation of remediation systems. In the 4th Edition of the European Code against Cancer it is therefore recommended to: "Find out if you are exposed to radiation from naturally high radon levels in your home. Take action to reduce high radon levels". Non-ionising types of radiation (those with insufficient energy to ionise molecules) - including extremely low-frequency electric and magnetic fields as well as radiofrequency electromagnetic fields - are not an established cause of cancer and are therefore not addressed in the recommendations to reduce cancer risk.

  13. Flash ionisation signature in coherent cyclotron emission from Brown Dwarfs

    CERN Document Server

    Vorgul, Irena

    2016-01-01

    Brown dwarfs form mineral clouds in their atmospheres, where charged particles can produce large-scale discharges in form of lightning resulting in a substantial sudden increase of local ionisation. Brown dwarfs are observed to emit cyclotron radio emission. We show that signatures of strong transient atmospheric ionisation events (flash ionisation) can be imprinted on a pre-existing radiation. Detection of such flash ionisation events will open investigations into the ionisation state and atmospheric dynamics. Such ionisation events can also result from explosion shock waves, bursts or eruptions. We present an analytical model that describes the modulation of a pre-existing electromagnetic radiation by a time-dependent (flash) conductivity that is characteristic for flash ionisation events like lightning. Our conductivity model reproduces the conductivity function derived from observations of Terrestrial Gamma Ray Flashes, and is applicable to astrophysical objects with strong temporal variations in the loca...

  14. Critical ionisation velocity effects in astrophysical plasmas

    International Nuclear Information System (INIS)

    Critical ionisation velocity effects are relevant to astrophysical situations where neutral gas moves through a magnetised plasma. The experimental significance of the critical velocity is well established and the physical basis is now becoming clear. The underlying mechanism depends on the combined effects of electron impact ionisation and electron energisation by collective plasma interactions. For low density plasmas a theory based on a circular process involving electron heating through a modified two stream instability has been developed. Several applications of critical velocity effects to astrophysical plasmas have been discussed in the literature. The importance of the effect in any particular case may be determined from a detailed consideration of energy and momentum balance, using appropriate atomic rate coefficients and taking full account of collective plasma processes. (Auth.)

  15. Characterization and pharmacological modulation of intestinal inflammation induced by ionizing radiation; Caracterisation et modulation pharmacologique de l'inflammation intestinale induite par les rayonnements ionisants

    Energy Technology Data Exchange (ETDEWEB)

    Gremy, O

    2006-12-15

    The use of radiation therapy to treat abdominal and pelvic malignancies inevitably involves exposure of healthy intestinal tissues which are very radiosensitive. As a result, most patients experience symptoms such as abdominal pain, nausea and diarrhea. Such symptoms are associated with acute damage to intestine mucosa including radio-induced inflammatory processes. With a rat model of colorectal fractionated radiation, we have shown a gradual development of a colonic inflammation during radiation planning, without evident tissue injury. This radio-induced inflammation is characterized not only by the sur expressions of pro-inflammatory cytokines and chemokines, a NF-kB activation, but also by a repression of anti-inflammatory cytokines and the nuclear receptors PPARa and RXRa, both involved in inflammation control. This early inflammation is associated with a discreet neutrophil recruitment and a macrophage accumulation. Macrophages are still abnormally numerous in tissue 27 weeks after the last day of irradiation. Inflammatory process is the most often related to a specific immune profile, either a type Th1 leading to a cellular immune response, or a type Th2 for humoral immunity. According to our studies, a unique abdominal radiation in the rat induces an ileum inflammation and an immune imbalance resulting in a Th2-type profile. Inhibiting this profile is important as its persistence promotes chronic inflammation, predisposition to bacterial infections and fibrosis which is the main delayed side-effect of radiotherapy. The treatment of rats with an immuno-modulator compound, the caffeic acid phenethyl ester (C.A.P.E.), have the potential to both reduce ileal mucosal inflammation and inhibit the radio-induced Th2 status. In order to search new therapeutic molecular target, we has been interested in the PPARg nuclear receptor involved in the maintenance of colon mucosal integrity. In our abdominal irradiation model, we have demonstrated that the prophylactic treatment with a PPARg synthetic ligand, the so-called 5-aminosalicylic acid (5-ASA), protects against the development of the acute mucosal colon inflammation. This pharmacological drug restrains radio-induced expression of pro inflammatory molecular actors such as TNFa, MCP-1 and iNOS, it also limits the repression of nuclear receptors involved in inflammation control such as PPARg, and reduces the radio-induced accumulation of macrophages. These results could give some leads to find therapeutic drug to limit radio-induced early mucosal and consequently, to improve patients' comfort during and after the radiotherapy schedule. (author)

  16. Synthesis and evaluation of new protecting agents against ionizing radiations; Synthese et evaluation de nouveaux agents de protection contre les rayonnements ionisants

    Energy Technology Data Exchange (ETDEWEB)

    Nadal, B.

    2009-10-15

    This thesis is devoted to the synthesis of new pulvinic acid derivatives and the evaluation of their antioxidant and radioprotective properties. This study has been conducted with the aim to develop new protecting agents against ionizing radiations. A new access to pulvinic acid derivatives was developed starting from L-dimethyl tartrate. It is based on a Dieckmann cyclization a dehydration and a Suzuki-Miyaura coupling. It allows a short effective preparation of various pulvinic acid derivatives: tetronic acid derivatives, mono-substituted pulvinic acid derivatives and methyl pulvinates. A modified method has been used to prepare pulvinones. This strategy gave access in four steps to the desired pulvinones. The rapidity of this method is provided by a tandem process, carried out in the final step, involving a Dieckmann cyclization and a {beta}-elimination. A synthesis of 3-aryltetramic acids has also been developed in order to prepare nitrogen derivatives of pulvinic acid. The antioxidant activity of the prepared compounds was then evaluated using various tests: DPPH, ABTS, protection of thymidine and DNA study of lipid peroxidation. These evaluations allowed to define interesting structure-activity relationships of pulvinic derivatives. They have shown that several derivatives have very good antioxidant activities. Finally, radioprotective tests on TK6 cells and mice have have been performed on selected compounds. (author)

  17. Food ionisation. Realities and perspectives; L'ionisation alimentaire. Realites et perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Bonnet, G

    1994-06-01

    The ionisation of food is a treatment using a certain type of energy. the radiations used in the industrial treatments are limited to three sources. The gamma radiations, the x radiations and the electrons beams emitted with accelerators. The physical treatments by ionizing radiations have for aim to cleanse and to increase the conservation time of food. Now, the applications in agriculture and food industry, are still marginal. The industrial using ionisation are these ones that did not find any alternative decontamination method. The barriers are more scientific or technical or economical than a question of regulation or behaviour. (N.C.)

  18. Ionising energy treatment of fresh fruit

    International Nuclear Information System (INIS)

    The main purposes of the ionising energy treatment of fresh fruit are: the extension of shelf life of the commodity due to a direct physiological effect on the particular product; the extension of shelf life of the commodity due to a reduction in the development of moulds and rots which would normally render the product worthless; and the killing of insect pests of quarantine significance, to allow for normal marketing of fresh fruit without the risk of introducing insect pests to previously pest-free areas

  19. Effects of the ionising radiations on the structure and the function of the intestinal epithelial cell; Effets des rayonnements ionisants sur la structure et la fonction de la cellule epitheliale intestinale

    Energy Technology Data Exchange (ETDEWEB)

    Haton, C

    2005-06-15

    The intestinal mucosa is a particularly radio-sensitive tissue and damage may occur following either accidental or therapeutic exposure. the deleterious actions of ionizing radiation are linked to the formation of sometimes overwhelming quantities of reactive oxygen species (R.O.S.). Production of R.O.S. is both direct and indirect from the secondary effects of irradiation. A better comprehension of the underlying mechanisms of injury will lead to more adapted therapeutic approaches to limit the harmful effects of irradiation. The homeostasis of the intestinal epithelium is regulated by three factors: proliferation, apoptosis and differentiation. these three factors were studied using the cell model, HT29, in order to analyze modulations of this balance after irradiation. our results, in agreement with other data, showed the establishment of mitotic delay. This arrest of proliferation was followed by apoptosis to be the major mechanism leading to cell death in this model. thus, for the first time, we have shown that irradiated intestinal epithelial cells preserve their capacity to differentiate. This indicates, although indirectly, that intestinal cells have and preserve an intrinsic capacity restore a functional epithelium. R.O.S. are considered as intermediates between the physical nature of radiations and biological responses. It seems essential to understand anti-oxidant mechanisms used by the cell for defence against the deleterious effects of R.O.S post exposure. This study of several anti-oxidant defence mechanisms of intestinal mucosa, was carried out in vivo in the mouse at different times following abdominal irradiation. We observed an early mitochondrial response in the hours following irradiation revealing this organelle as a particular target. We demonstrated a strong alteration of anti-oxidant capacity as revealed by a decrease in S.O.D.s, catalase and an increase of the G.P.X.s and M.T.s. A part of these modifications appeared to depend on an irradiation-induced inflammatory response. Finally, we showed that the loss of catalase is linked to the onset of structural damage to the mucosa. All of these results orient therapeutic strategies towards inducing the proliferation of crypt cells, rather than an inhibition of apoptosis, since the epithelial cells retain differentiation capacity and so production of functional cells. (aut0009h.

  20. Behaviour of an irradiated photomultiplier; Etude du comportement d'un photomultiplicateur sous rayonnements nucleaires

    Energy Technology Data Exchange (ETDEWEB)

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

    1967-04-15

    transitoires, le controle ou la s ete d'un reacteur nucleaire ou d'un assemblage critique, nous avons etudie le comportement de 8 photomultiplicateurs Radiotechnique 51 AVP et UVP et EMI 9 524 B dans le flux gamma d'un puits de stockage de 1 a 10{sup 3} Rh{sup -1} et dans un canal de pile a EL 2 ou le domaine d'exposition variait de 1 a 2. 10{sup 3} Rh{sup -1} et 6. 10{sup 5} a 5. 10{sup 7} n.cm{sup -2}.s{sup -1}. Des impulsions parasites a l'anode du photomultiplicateur sont produites par ces rayonnements. En comparant les amplitudes de ces impulsions a celles delivrees par un scintillateur NaI, on a constate que leur niveau maximal etait d'une centaine de keV a 10{sup 3} Rh{sup -1} dans le flux gamma du puits de stockage, et de 200 a 400 keV a 10{sup 3} Rh{sup -1} et 10{sup 7} n.cm{sup -2}.s{sup -1} dans le canal de pile. D'autre part, la detection d'une impulsion lumineuse de reference, correspondant a 200 keV (NaI) n'est perturbee qu'au dela de quelques centaines de Rh{sup -1} par le rayonnement {gamma} seul, et de 5. 10{sup 6} n.cm{sup -2} s{sup -1} et {approx}500 Rh{sup -1} dans le canal de pile. La dispersion de ces resultats est de l'ordre de 2 pour les 8 tubes eprouves. Nous attribuons a l'effet Cerenkov dans la fenetre du photomultiplicateur, la part principale des effets du rayonnement {gamma}. La discrimination des effets respectifs des neutrons et du rayonnement {gamma} est abordee. Nous n'avons pas constate d'evolution sensible des parametres des photomultiplicateurs etudies, pendant les expositions. Leurs caracteristiques n'ont pas ete modifiees par les doses recues dont le maximum etait de 4.10{sup 12} neutrons.cm{sup 2} et {approx_equal} 3. 10{sup 4} roentgens. L'interet de l'emploi de photomultiplicateurs et circuits rapides, pour reculer les limites d'emploi des photomultiplicateurs sous rayonnements est souligne. (auteur)

  1. Cosmic-ray ionisation in collapsing clouds

    CERN Document Server

    Padovani, Marco; Galli, Daniele

    2013-01-01

    Cosmic rays (CR) play an important role in dense molecular cores, affecting their thermal and dynamical evolution and initiating the chemistry. Several studies have shown that the formation of protostellar discs in collapsing clouds is severely hampered by the braking torque exerted by the entrained magnetic field on the infalling gas, as long as the field remains frozen to the gas. We examine the possibility that the concentration and twisting of the field lines in the inner region of collapse can produce a significant reduction of the ionisation fraction. To check whether the CR ionisation rate (CRir) can fall below the critical value required to maintain good coupling, we first study the propagation of CRs in a model of a static magnetised cloud varying the relative strength of the toroidal/poloidal components and the mass-to-flux ratio. We then follow the path of CRs using realistic magnetic field configurations generated by numerical simulations of a rotating collapsing core. We find that an increment of...

  2. Contribution aux Methodes Analytiques des Substances a L'aide de Faisceaux de Particules Chargees

    Science.gov (United States)

    Saidi, Abdelmajid

    Nous avons vu les possibilites d'analyse par particules chargees des aerosols recueillis sur des filtres de type MILLIPORE. La meme technique a ete utilisee pour des filtres ayant servi a la filtration de l'eau du fleuve Saint-laurent. Deux techniques ont ete utilisees: (1) FAST (Forward Alpha Scattering Technique): pour analyser l'hydrogene, le carbone, l'oxygene et puis l'azote. Des alpha de 12 MeV ont ete utilises. (2) PIXE (Particle Induced X-ray Emission): pour analyser les elements moyens et lourds, dans ce cas des protons de 3 MeV ainsi que des ions d'argon de 1 et 1.6 MeV ont ete utilises. Les etudes ont montre que sous vide, la majorite des problemes proviennent des dommages causes par l'echauffement du a l'impact du faisceau sur le filtre. L'analyse quantitative par l'intermediaire du faisceau extrait peut presenter des difficultes en ce qui concerne les elements legers pour lesquels l'absorption des rayonnements caracteristiques dans l'atmosphere externe est importante. Les ions lourds se pretent mal aux analyses des aerosols du fait de leur limite de sensibilite. L'analyse directe de liquides par des protons est particulierement interessante puisqu'elle ne necessite aucune preparation prealable des echantillons. A cet effet, un programme de calcul de concentration des elements dans la solution a analyser a ete mis au point. Nous avons determine la limite de sensibilite de la methode PIXE pour les cibles minces (filtre) et pour le cas ou la matrice est de l'eau. Enfin, la technique FAST peut etre un complement de la technique PIXE.

  3. Aux marges du monde arabe

    Directory of Open Access Journals (Sweden)

    Hélène Thiollet

    2004-09-01

    Full Text Available L’étude des migrations contemporaines des Érythréens vers le Yémen au tournant des années quatre-vingt-dix permet d’observer les transformations des dynamiques régionales à l’œuvre dans le monde arabe. Les migrations sont un phénomène sensible aux différents aspects (politiques, économiques, culturels, géographiques de l’intégration régionale. Celle si est envisagée dans cet article à travers une approche doublement marginale : -la marginalité géographique de l’Érythrée arabo-africaine et du Yémen, économi­quement isolé dans la péninsule Arabique, -l’étude des migrations formelles et informelles, élément souvent marginal dans l’étude des institutions et des échanges qui constituent un système régional intégré. Cette étude est fondée sur une série d’entretiens menés au Yémen entre février et avril 2002 auprès des administrations yéménites et de la population érythréenne.

  4. Introduction to analytical techniques of beam-target interactions and resolutions; Introduction aux techniques d`analyse interactions rayonnement-matiere et resolutions

    Energy Technology Data Exchange (ETDEWEB)

    Ruste, J.

    1995-08-01

    For several years, new analysis and observation techniques have been developed, which have considerably improved material research. Almost all these techniques are based on the interaction of a beam of `primary particles` (electrons, photons, ions, particles, etc) with target. Correct and appropriate use of these techniques requires a good knowledge of these interactions and their consequences (emissions of `secondary particles`, modifications of the primary beam and target, etc). The first part of this report deals with the radiation/material interactions according to the nature of the radiation and its energy. The nature and consequences of the interaction of an electromagnetic wave, a beam of electrons, ions and neutrons are examined over an extended range of energy from MeV to MeV. Certain notions such as the analysis area, spatial resolutions or limits of detection can also be defined. In the second part, some of the most important and widespread techniques of analysis and observation are compared in terms of properties and performance. In particular, there is a brief principle of the technique, nature of the data obtained, spatial resolution, and the limits of detection with today`s methods permit. (author). 5 refs., 23 figs., 9 tabs.

  5. Apport du rayonnement synchrotron à l'étude de cheveux archéologiques

    Science.gov (United States)

    Bertrand, L.; Chevallier, P.; Doucet, J.; Simionovici, A.; Tsoucaris, G.; Walter, P.

    2002-07-01

    La préservation dans certains contextes archéologiques des cheveux humains et des fibres animales est favorisée par leur transformation chimique au contact d'objets métalliques. Afin de mieux comprendre les phénomènes complexes mis en jeu, nous avons étudié expérimentalement la fixation de cations métalliques (Cu et Pb) dans des cheveux modèles à partir de différentes méthodes de caractérisation utilisant le rayonnement X synchrotron. Nous avons ainsi pu mettre en évidence la fixation spécifique d'une partie de ces cations au sein des lipides structurés du cheveu. La comparaison entre échantillons modèles et archéologiques apporte de nouvelles données concernant les premières étapes d'altération des cheveux archéologiques.

  6. Development of an optical digital ionisation chamber

    International Nuclear Information System (INIS)

    We are developing a new device for optically detecting and imaging the track of a charged particle in a gas. The electrons in the particle track are made to oscillate rapidly by the application of an external, short duration, high voltage, RF electric field. The excited electrons produce additional ionisation and electronic excitation of the gas molecules in their immediate vicinity, leading to copious light emission (fluorescence) from the selected gas, allowing the location of the electrons along the track to be determined. Two digital cameras simultaneously scan the emitted light across two perpendicular planes outside the chamber containing the gas. The information thus obtained for a given track can be used to infer relevant quantities for microdosimetry and dosimetry, e.g. energy deposited, LET, and track structure in the gas. The design of such a device now being constructed and methods of obtaining the dosimetric data from the digital output will be described. (author)

  7. Effects of the electric field on ionisation in two different types of ionisation chambers

    International Nuclear Information System (INIS)

    A parallel plate cavity ionisation chamber was irradiated with 60Co γ rays from the polarising electrode. Beyond the recombinations region, the output current of the chamber increases (decreases) linearly with applied positive (negative) voltage. This effect is attributed to the change in the stopping power of air due to acceleration or deceleration of secondary electrons in the applied electric field. In a free-air ionisation chamber, secondary electrons emitted in the direction of the electric field lose energy and those emitted in the opposite direction gain energy and, hence, cause a reduction or enhancement in ionisation, respectively. Computer calculations have shown that the enhancement and reduction are in a range from 0.15 to 0.3% when exposure is measured for X rays generated at a tube voltage of 60-300 kV and at an electric field strength of 20 KV.m-1. The net increase in the output current change at this field strength is smaller than the calculation uncertainties. (author)

  8. Germanium junction detectors. Theoretical and practical factors governing their use in radiation spectrometry; Detecteurs a jonction au germanium. Elements theoriques et pratiques pour l'utilisation en spectrometrie de rayonnements

    Energy Technology Data Exchange (ETDEWEB)

    Hors, M.; Philis, C. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1967-07-01

    Semi-conductor detectors have recently greatly increased the possibilities available to nuclear spectroscopists for the study of {alpha}, {beta} and {gamma} radiations. Their use in radio-chemistry has encouraged us to study their principle, their mechanism and also the conditions under which they can be used. The first part, which is theoretical, consists of a summary of what should be known concerning the best use of junction detectors, in particular Ge (Li) detectors. The second part, which is experimental, summarizes the laboratory work carried out over a period of one year on Ge (Li) detectors. Stress is laid on the possibilities presented by the use of these detectors as photo-electric spectrometers, and also on the precautions required. Amongst the numerous results presented, the resolution of 2.52 keV obtained for the {gamma} radiation of 145.5 keV for {sup 141}Ce may be particularly noted. (authors) [French] Les detecteurs a semi-conducteurs ont recemment accru les possibilites offertes aux spectroscopistes nucleaires pour l'etude des radiations {alpha}, {beta}, {gamma}. Leurs utilisations en radiochimie nous ont incite a en etudier le principe, le mecanisme et d'autre part les conditions d'emploi. La premiere partie, theorique, rappelle l'essentiel de ce qu'il est utile de connaitre pour une utilisation optimale des detecteurs a jonctions et en particulier des detecteurs Ge (Li). La deuxieme partie, experimentale, resume les travaux realises au laboratoire pendant un an avec des detecteurs Ge (Li). Nous insistons sur les possibilites offertes et les precautions a prendre dans l'utilisation de ces detecteurs comme spectrometres photoelectriques. Parmi les nombreux resultats presentes, citons la resolution de 2,52 keV obtenue pour le rayonnement {gamma} de 145 f5 keV du {sup 141}Ce. (auteurs)

  9. Innershell ionisation at small impactparameters in proton-atom collisions

    International Nuclear Information System (INIS)

    This thesis concentrates on innershell ionisation in proton-atom collisions. An experiment on K-shell ionisation of argon is described, performed in a gasfilled collision chamber under single collision conditions. Further experiments with carbon and aluminium were performed, the K-shell vacancy production in the collision of protons with these atoms being detected through the measurement of Auger-electrons. A spectrometer with a large solid angle was specially constructed for this and its performance is described. K-shell ionisation accompanying nuclear (p,γ) reactions has also been measured using 26Mg and 27Al. (Auth./C.F.)

  10. Non-equilibrium calcium ionisation in the solar atmosphere

    CERN Document Server

    Wedemeyer-Böhm, Sven

    2011-01-01

    Our aim is to determine the dominant processes and timescales for the ionisation equilibrium of calcium under solar chromospheric conditions. The study is based on numerical simulations with the RADYN code, which includes hydrodynamics, radiative transfer, and a detailed non-equilibrium treatment of hydrogen, calcium, and helium. The simulations are characterised by upwards propagating shock waves, which cause strong temperature fluctuations and variations of the ionisation degree of calcium. The passage of a hot shock front leads to a strong net ionisation of Ca II, rapidly followed by net recombination. The relaxation timescale of the Ca ionisation state is found to be of the order of a few seconds at the top of the photosphere and 10 to 30 s in the upper chromosphere. Generally, the timescales are significantly reduced in the wakes of hot shock fronts. The timescales can be reliably determined from a simple analysis of the eigenvalues of the transition rate matrix. The timescales are dominated by the radia...

  11. QUANTIFICATIONS OF THE DETRIMENTAL HEALTHEFFECTS OF IONISING RADIATION

    OpenAIRE

    Walsh, Linda

    2013-01-01

    This thesis, presented to The University of Manchester in 2012 by Dr. Linda Walsh, is in fulfilment of the requirements for the degree of Doctor of Science (DSc) and is entitled “Quantifications of the detrimental health effects of ionising radiation.” A body of work and ensuing publications covering 2000–2012 are presented, predominantly concerning studies of various cohorts of people exposed to ionising radiation. The major areas cover epidemiological and statistical studies on the Life spa...

  12. The effectiveness of photocatalytic ionisation disinfection of filter materials.

    Science.gov (United States)

    Pietrzak, Katarzyna; Gutarowska, Beata

    2013-01-01

    The purpose of this study was to determine the effectiveness of photocatalytic ionisation as a disinfection method for filter materials contaminated by microorganisms, and to assess how air relative humidity (RH), time and microbe type influence the effectiveness of this disinfection. In the quantitative analysis of a used car air filter, bacterial contamination equalled 1.2 x 10(5) cfu/cm2, fungal contamination was 3.8 x 10(6) cfu/cm2, and the isolated microorganisms were Aspergillus niger, Bacillus megaterium, Cladosporium herbarum, Cryptococcus laurenti, Micrococcus sp., Rhodotorula glutinis and Staphylococcus cohnii. In the model experiment, three isolates (C. herbarum, R. glutinis, S. cohnii) and 3 ATCC species (A. niger, E. coli, S. aureus) were used for photocatalytic ionisation disinfection. The conditions of effective photocatalytic ionisation disinfection (R > or = 99.9%) were established as 2-3 h at RH = 77% (bacteria) and 6-24 h at RH = 53% (fungi). RH has an influence on the effectiveness of the photocatalytic disinfection process; the highest effectiveness was obtained for bacteria at RH = 77%, with results 5% higher than for RH = 49%. The studies show that the sensitivity of microorganisms to photocatalytic ionisation disinfection is ordered as follows: Gram-positive bacteria (S. cohnii, S. aureus), Gram-negative bacteria (E. coli), yeasts (R. glutinis), and moulds (C. herbarum, A. niger). Of all the mathematical models used for the description of death dynamics after photocatalytic ionisation disinfection, the Chick-Watson model is the most useful, but for more resistant microorganisms, the delayed Chick-Watson model is highly recommended. It therefore seems, that the presented disinfection method of photocatalytic ionisation can be successfully used to clean filtration materials.

  13. {alpha} Spectroscopy by the method of grid ionization grid chamber, application to the case of uranium; Spectrographie {alpha} par la methode de la chambre d'ionisation a grille application a l'uranium

    Energy Technology Data Exchange (ETDEWEB)

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

    1951-06-15

    Le present work had for aim the verification of the operating of an equipment: chamber of grid ionization, amplifiers and discriminator with nine channels, constructed by the, Commissariat a l'energie Atomique to serve for the {alpha} spectroscopy. To this occasion, different measurements had been done on a source of uranium: energy of the {alpha} of U{sub 234} and U{sub 235} according to those of them {alpha} of U{sub 238} taken as standard, relative intensities, of the {alpha} radiation of the three isotopes and notably of the low abundant group due to the isotope 235. (author) [French] Le present travail a eu pour objet la verification du fonctionnement d'un appareillage: chambre d'ionisation a grille, amplificateurs et discriminateur a neuf canaux, construit par le Commissariat a l'Energie Atomique pour servir a la spectroscopie {alpha}. A cette occasion, differentes mesures ont ete effectuees sur une source d'uranium: energie des {alpha} de U{sub 234} et de U{sub 235} en fonction de celle des {alpha} de U{sub 238} prise pour etalon, intensites relatives des rayonnement {alpha} des trois isotopes et notamment du groupe peu abondant du a l'isotope 235. (auteur)

  14. An application of resonant ionisation spectroscopy to accelerator based high energy physics

    International Nuclear Information System (INIS)

    The simulation of charged particle tracks by pulsed UV lasers is now used extensively in the calibration of multiwire drift chambers. The identity of the trace quantities of low ionisation potential impurities responsible for the laser induced ionisation in conventional chamber gases has caused much discussion. Using two photon resonant ionisation spectroscopy two of the major sources of ionisation in proportional counters have been identified as phenol and toluene. (author)

  15. Substrate-dependent Aux cluster: A new insight into Aux/CeO2

    Science.gov (United States)

    Zhu, Kong-Jie; Yang, Yan-Ju; Lang, Jia-Jian; Teng, Bo-Tao; Wu, Feng-Min; Du, Shi-Yu; Wen, Xiao-Dong

    2016-11-01

    To theoretically study the structures of metal clusters on oxides is very important and becomes one of the most challenging works in computational heterogeneous catalysis since many factors affect their structures and lead to various possibilities. In this work, it is very interesting to find that the stable structures and stability evolution of Aux clusters on ceria are varied with different index surfaces of CeO2. The corresponding reasons in chemical, geometric and electronic properties are systematically explored. Aux (x = 1-4) clusters prefer to separately disperse at the O-O bridge sites on CeO2(100) due to the low coordination number of surface O; while aggregate due to the strong Au-Au attractions when x is larger than 4. Owing to the uniform distribution of O-O bridge sites on CeO2(111) and (100), the most stable configurations of Aux are 3D structures with bottom atoms more than top ones when x is larger than 4. However, 2D configurations of Aux/CeO2(110) (x < 10) are more stable than the corresponding 3D structures due to the particular O-O arrangement on CeO2(110). 3D Aux clusters across O-O-Y lines are suggested as the most stable configurations for Aux/CeO2(110) (x ≥ 10). The present work gives a detailed example for the theoretical study of metal clusters on oxide, and will shed light into the design for controllable synthesis of ceria-based catalysts with metal nanoparticles supported on CeO2.

  16. An implementation of ionisation energy loss in very thin absorbers for the GEANT4 simulation package

    CERN Document Server

    Apostolakis, John; Urbàn, L; Maire, M; Bagulya, A V; Grichine, V M

    2000-01-01

    We discuss an implementation of Photo Absorption Ionisation model describing ionisation energy loss produced by a relativistic charged particle in very thin absorbers. The implementation allows us to calculate ionisation energy losses in any material consisting of elements with atomic numbers in the range 1-100. Comparisons of simulation with the experimental data from gaseous and solid state detectors are presented. (24 refs).

  17. Notes de voyage aux Iles Baleares

    Directory of Open Access Journals (Sweden)

    Maurice LOUIS

    2009-10-01

    Full Text Available Les excursions du 1Vº Cours de Préhistoire et d'Archéologie, organisé en 1950 par l'Université de Barcelone en collaboratión avec l'Institut de Prehistoire méditerranéenne du Consejo Superior de Investigaciones Científicas d'Espagne, on conduit les participants aux Iles Baléares afin d'étudier sur place la civilisation dite "des talayots" de Majorque et de Minorque.

  18. Assistance et discipline, introduction aux articles

    Directory of Open Access Journals (Sweden)

    Jean-Claude Vimont

    2012-07-01

    Full Text Available Quand Michel Foucault publie Surveiller et punir en 1975, aux lendemains de trois années de mutineries dans l'univers carcéral, il ne se contente pas d'offrir une généalogie de la prison moderne, mais analyse les systèmes disciplinaires à l'oeuvre dans d'autres institutions. Les études que nous reproduisons dans cette rubrique incitent à une réflexion sur la dimension coercitive de certains dispositifs d'assistance et de soins. Non de manière statique, car les oeuvres, les institutions évolue...

  19. Airborne laser-spark for ambient desorption/ionisation.

    Science.gov (United States)

    Bierstedt, Andreas; Riedel, Jens

    2016-01-01

    A novel direct sampling ionisation scheme for ambient mass spectrometry is presented. Desorption and ionisation are achieved by a quasi-continuous laser induced plasma in air. Since there are no solid or liquid electrodes involved the ion source does not suffer from chemical interferences or fatigue originating from erosive burning or from electrode consumption. The overall plasma maintains electro-neutrality, minimising charge effects and accompanying long term drift of the charged particles trajectories. In the airborne plasma approach the ambient air not only serves as the plasma medium but at the same time also slows down the nascent ions via collisional cooling. Ionisation of the analyte molecules does not occur in the plasma itself but is induced by interaction with nascent ionic fragments, electrons and/or far ultraviolet photons in the plasma vicinity. At each individual air-spark an audible shockwave is formed, providing new reactive species, which expands concentrically and, thus, prevents direct contact of the analyte with the hot region inside the plasma itself. As a consequence the interaction volume between plasma and analyte does not exceed the threshold temperature for thermal dissociation or fragmentation. Experimentally this indirect ionisation scheme is demonstrated to be widely unspecific to the chemical nature of the analyte and to hardly result in any fragmentation of the studied molecules. A vast ensemble of different test analytes including polar and non-polar hydrocarbons, sugars, low mass active ingredients of pharmaceuticals as well as natural biomolecules in food samples directly out of their complex matrices could be shown to yield easily accessible yet meaningful spectra. Since the plasma medium is humid air, the chemical reaction mechanism of the ionisation is likely to be similar to other ambient ionisation techniques. Wir stellen hier eine neue Ionisationsmethode für die Umgebungsionisation (ambient ionisation) vor. Sowohl die

  20. Cytogenetic effects of low ionising radiation doses and biological dosimetry

    OpenAIRE

    Gricienė, Birutė

    2010-01-01

    The intensive use of ionising radiation (IR) sources and development of IR technology is related to increased exposure and adverse health risk to workers and public. The unstable chromosome aberration analysis in the group of nuclear energy workers (N=84) has shown that doses below annual dose limit (50 mSv) can induce chromosome aberrations in human peripheral blood lymphocytes. Significantly higher frequencies of the total chromosome aberrations were determened in the study group when compa...

  1. Basic radiation chemistry for the ionising energy treatment of food

    International Nuclear Information System (INIS)

    Before we can understand the chemistry involved in the irradiation of complex substances such as food we need to have some appreciation of the reactions involved and the products formed when ionising energy interacts with the simple substances such as water and dilute solutions. Reactions involving hydrated electrons, hydrogen atoms and hydroxyl radicals are examined and methods for minimising radiolytic effects in foods are discussed

  2. IEC standards for individual monitoring of ionising radiation

    International Nuclear Information System (INIS)

    This paper presents IEC/SC 45B 'Radiation protection instrumentation' and its standards for individual monitoring of ionising radiation: IEC 61526 Ed. 3 for active personal dosemeters and IEC 62387-1 for passive integrating dosimetry systems. The transposition of these standards as CENELEC (European) standards is also discussed together with the collaboration between IEC/SC 45B and ISO/TC 85/SC 2. (authors)

  3. Impact ionisation measurement and modelling of long wavelength avalanche photodiodes

    CERN Document Server

    Ng, J S

    2003-01-01

    Impact ionisation coefficients are measured in In sub 0 sub . sub 5 sub 3 Ga sub 0 sub . sub 4 sub 7 As and excess noise characteristics are measured in sub-micron ln sub 0 sub . sub 5 sub 2 Al sub 0 sub . sub 4 sub 8 As. Photomultiplication measurements performed on a series of In sub 0 sub . sub 5 sub 3 Ga sub 0 sub . sub 4 sub 7 As p-i-n diodes are reported. Taking careful account of factors which could give rise to erroneous results at low fields, ln sub 0 sub . sub 5 sub 3 Ga sub 0 sub . sub 4 sub 7 As ionisation coefficients are deduced at room temperature as a function of electric field. The results confirm the low field ionisation behaviour of alpha and the conventional field dependence of beta. Excess avalanche noise factors of In sub 0 sub . sub 5 sub 2 Al sub 0 sub . sub 4 sub 8 As p-i-n diodes, with i-region thicknesses ranging from 1.0 mu m to 0.1 mu m, are reported. The results indicate effective beta/alpha values lying between 0.15 and 0.23, comparable with or lower than the values reported in ...

  4. Complex systems of biological interest stability under ionising radiations

    International Nuclear Information System (INIS)

    This PhD work presents the study of stability of molecular systems of biological interest in the gas phase after interaction with ionising radiations. The use of ionising radiation can probe the physical chemistry of complex systems at the molecular scale and thus consider their intrinsic properties. Beyond the fundamental aspect, this work is part of the overall understanding of radiation effects on living organisms and in particular the use of ionizing radiation in radiotherapy. Specifically, this study focused on the use of low-energy multiply charged ions (tens of keV) provided by the GANIL (Caen), which includes most of the experiments presented. In addition, experiments using VUV photons were also conducted at synchrotron ELETTRA (Trieste, Italy). The bio-molecular systems studied are amino acids and nucleic acid constituents. Using an experimental crossed beams device allows interaction between biomolecules and ionising radiation leads mainly to the ionization and fragmentation of the system. The study of its relaxation dynamics is by time-of-flight mass spectrometry coupled to a coincidences measurements method. It is shown that an approach combining experiment and theory allows a detailed study of the fragmentation dynamics of complex systems. The results indicate that fragmentation is generally governed by the Coulomb repulsion but the intramolecular rearrangements involve specific relaxation mechanisms. (author)

  5. Erich Regener and the maximum in ionisation of the atmosphere

    CERN Document Server

    Carlson, P

    2014-01-01

    In the 1930s the German physicist Erich Regener (1881-1955) did important work on the measurement of the rate of production of ionisation deep under-water and in the atmosphere. He discovered, along with one of his students, Georg Pfotzer, the altitude at which the production of ionisation in the atmosphere reaches a maximum, often, but misleadingly, called the Pfotzer maximum. Regener was one of the first to estimate the energy density of cosmic rays, an estimate that was used by Baade and Zwicky to bolster their postulate that supernovae might be their source. Yet Regener's name is less recognised by present-day cosmic ray physicists than it should be largely because in 1937 he was forced to take early retirement by the National Socialists as his wife had Jewish ancestors. In this paper we briefly review his work on cosmic rays and recommend an alternative naming of the ionisation maximum. The influence that Regener had on the field through his son, his son-in-law, his grandsons and his students and through...

  6. Electrospray ionisation mass spectrometry: principles and clinical applications.

    Science.gov (United States)

    Ho, C S; Lam, C W K; Chan, M H M; Cheung, R C K; Law, L K; Lit, L C W; Ng, K F; Suen, M W M; Tai, H L

    2003-01-01

    This mini-review provides a general understanding of electrospray ionisation mass spectrometry (ESI-MS) which has become an increasingly important technique in the clinical laboratory for structural study or quantitative measurement of metabolites in a complex biological sample. The first part of the review explains the electrospray ionisation process, design of mass spectrometers with separation capability, characteristics of the mass spectrum, and practical considerations in quantitative analysis. The second part then focuses on some clinical applications. The capability of ESI-tandem-MS in measuring bio-molecules sharing similar molecular structures makes it particularly useful in screening for inborn errors of amino acid, fatty acid, purine, pyrimidine metabolism and diagnosis of galactosaemia and peroxisomal disorders. Electrospray ionisation is also efficient in generating cluster ions for structural elucidation of macromolecules. This has fostered a new and improved approach (vs electrophoresis) for identification and quantification of haemoglobin variants. With the understanding of glycohaemoglobin structure, an IFCC reference method for glycohaemoglobin assay has been established using ESI-MS. It represents a significant advancement for the standardisation of HbA1c in diabetic monitoring. With its other applications such as in therapeutic drug monitoring, ESI-MS will continue to exert an important influence in the future development and organisation of the clinical laboratory service.

  7. Introduction aux études historiques

    OpenAIRE

    Langlois, Charles-Victor; Seignobos, Charles; Noiriel, Gérard

    2014-01-01

    L’Introduction aux études historiques constitue le texte de référence de ce qu’on a appelé « l’école méthodique historique » française. Ce manuel cherche à définir les règles de la méthode historique afin de contribuer à asseoir la scientificité d’une discipline, l’histoire, dans le contexte de sa professionnalisation universitaire. Le texte affirme le primat des archives comme preuves et sources du récit historique, et revient sur les différentes étapes du travail sur archives, de la localis...

  8. Keeping the Universe ionised: Photo-ionisation heating and the critical star formation rate at redshift z = 6

    CERN Document Server

    Pawlik, Andreas H; van Scherpenzeel, Eveline

    2008-01-01

    The critical star formation rate density required to keep the intergalactic hydrogen ionised depends crucially on the average rate of recombinations in the intergalactic medium (IGM). This rate is proportional to the clumping factor C = / avg(rho_b)^2, where rho_b and avg(rho_b) are the local and cosmic mean baryon density, respectively, and the brackets indicate spatial averaging over the recombining gas in the IGM. We perform a suite of cosmological smoothed particle hydrodynamics simulations that include radiative cooling to calculate the volume-weighted clumping factor of the IGM at redshifts z >= 6. We focus on the effect of photo-ionisation heating by a uniform ultra-violet background and find that photo-heating strongly reduces the clumping factor because the increased pressure support smoothes out small-scale density fluctuations. Photo-ionisation heating is often said to provide a negative feedback on the reionisation of the IGM because it suppresses the cosmic star formation rate by boiling the ga...

  9. Dosimetry techniques of thermal neutrons and {gamma} radiation in reactor cores; Techniques de dosimetrie des neutrons thermiques et du rayonnement {gamma} dans les piles

    Energy Technology Data Exchange (ETDEWEB)

    Sutton, J.; Draganic, I.; Hering, H. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1955-07-01

    Chemical studies under radiation done in the reactor cores require to be followed by dosimetry. When the irradiations are done in the reflector, one can limit to the measure of the {gamma} and the neutron radiation. For the dosimetry of the {gamma} radiation, a dosimeter of ferrous sulfate is convenient until doses of about 10{sup 6} rep. The use of aired oxalic acid solutions permits to reach 10{sup 7} rep. The dosimetry of thermal neutrons has been made with solutions of cobalt sulphate or paper filter impregnated with this salt. The total chemical effect of the {gamma} and of the slow neutrons radiation is obtained with solutions of ferrous sulfate added with lithium sulphate. (M.B.) [French] Les etudes de chimie sous radiation faites dans les piles exigent d'etre suivies par dosimetrie. Lorsque les irradiations sont effectues dans le reflecteur, on peut se limiter a doser le rayonnement {gamma} et les neutrons. Pour la dosimetrie du rayonnement {gamma}, un dosimetre a sulfate ferreux convient jusqu'a des doses d'environ 10{sup 6} rep. L'emploi de solutions aerees d'acide oxalique permet d'atteindre 10{sup 7} rep. La dosimetrie des neutrons thermiques a ete faite avec des solutions de sulfate de cotalt ou du papier filtre impregne de ce sel. L'effet chimique total du rayonnement {gamma} et des neutrons lents est obtenu avec des solutions de sulfate ferreux additionne de sulfate de lithium. (M.B.)

  10. La diaspora, instrument de la politique de puissance et de rayonnement de l’Inde à l’île Maurice et dans le monde

    OpenAIRE

    Anouck Carsignol-Singh

    2009-01-01

    Les Persons of Indian Origin (PIO) ont depuis le début du XXe siècle servi de levier à l’intelligentsia indienne pour rehausser l’image du pays et contribuer à son rayonnement culturel sur la scène internationale, en tant qu’ambassadeurs culturels de l’Inde dans leur pays de résidence. Aujourd’hui, les nouveaux liens établis entre New Delhi et les Non Resident Indians (NRI) dépassent largement le cadre de la diplomatie culturelle, et leur mobilisation économique ou politique en faveur du trai...

  11. Semiclassical calculation of ionisation rate for Rydberg helium atoms in an electric field

    Institute of Scientific and Technical Information of China (English)

    Wang De-Hua

    2011-01-01

    The ionisation of Rydberg helium atoms in an electric field above the classical ionisation threshold has been examined using the semiclassical method, with particular emphasis on discussing the influence of the core scattering on the escape dynamics of electrons. The results show that the Rydberg helium atoms ionise by emitting a train of electron pulses. Unlike the case of the ionisation of Rydberg hydrogen atom in parallel electric and magnetic fields,where the pulses of the electron are caused by the external magnetic field, the pulse trains for Rydberg helium atoms are created through core scattering. Each peak in the ionisation rate corresponds to the contribution of one core-scattered combination trajectory. This fact further illustrates that the ionic core scattering leads to the chaotic property of the Rydberg helium atom in external fields. Our studies provide a simple explanation for the escape dynamics in the ionisation of nonhydrogenic atoms in external fields.

  12. Fitness of equipment used for medical exposures to ionising radiation

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-07-01

    The advice in this guidance note is aimed at employers in control of equipment used for medical exposures to ionising radiation and ancillary equipment. This includes NHS trusts, health authorities or boards, private hospitals, clinics, surgeries, medical X-ray facilities in industry, dentists and chiropractors. The guidance should also be useful to radiation protection advisers appointed by such employers. The guidance provides advice on the requirements of regulation 33 of the Ionising Radiations Regulations 1985 (IRR85). In particular, it covers: (a) the selection, installation, maintenance, calibration and replacement of equipment to ensure that it is capable of restricting, so far as reasonably practicable, the medical exposure of any person to the extent that this is compatible with the intended diagnostic or therapeutic purpose; (b) recommended procedures for the definitive calibration of radiotherapy treatment; and (c) the need to investigate incidents involving a malfunction or defect in any 'radiation equipment' which result in medical exposures much greater than intended and to notify the Health and Safety Executive (HSE). 'Medical exposure' is defined in IRR85 as exposure of a person to ionising radiation for the purpose of his or her medical or dental examination or treatment which is conducted under the direction of a suitably qualified person and includes any such examination or treatment conducted for the purposes of research. For convenience, people undergoing medical exposure will be referred to as 'patients' in this guidance. Nothing in this publication is intended to indicate whether or not patients should be informed of any incident resulting from malfunction or defect in equipment used for medical exposure and the possible consequences of that exposure. As stated above, this guidance concerns medical exposures much greater than intended and although exposures much lower than intended can also have serious

  13. Fitness of equipment used for medical exposures to ionising radiation

    International Nuclear Information System (INIS)

    The advice in this guidance note is aimed at employers in control of equipment used for medical exposures to ionising radiation and ancillary equipment. This includes NHS trusts, health authorities or boards, private hospitals, clinics, surgeries, medical X-ray facilities in industry, dentists and chiropractors. The guidance should also be useful to radiation protection advisers appointed by such employers. The guidance provides advice on the requirements of regulation 33 of the Ionising Radiations Regulations 1985 (IRR85). In particular, it covers: (a) the selection, installation, maintenance, calibration and replacement of equipment to ensure that it is capable of restricting, so far as reasonably practicable, the medical exposure of any person to the extent that this is compatible with the intended diagnostic or therapeutic purpose; (b) recommended procedures for the definitive calibration of radiotherapy treatment; and (c) the need to investigate incidents involving a malfunction or defect in any 'radiation equipment' which result in medical exposures much greater than intended and to notify the Health and Safety Executive (HSE). 'Medical exposure' is defined in IRR85 as exposure of a person to ionising radiation for the purpose of his or her medical or dental examination or treatment which is conducted under the direction of a suitably qualified person and includes any such examination or treatment conducted for the purposes of research. For convenience, people undergoing medical exposure will be referred to as 'patients' in this guidance. Nothing in this publication is intended to indicate whether or not patients should be informed of any incident resulting from malfunction or defect in equipment used for medical exposure and the possible consequences of that exposure. As stated above, this guidance concerns medical exposures much greater than intended and although exposures much lower than intended can also have serious consequences, the incident would not

  14. Ionising radiation safety training in the Australian defence organisation (ADO)

    International Nuclear Information System (INIS)

    Full text: Training personnel in ionising radiation safety within the Australian Defence Organisation (ADO) requires addressing some unique features of an organisation employing both military and civilian personnel. Activities may include those of a civil nature (such as industrial and medical radiography), specific military requirements (for training and emergency response) and scientific research and development. Some personnel may be assigned to full-time duties associated with radiation, while others may be designated as radiation protection officers in remote units with few duties to perform in this role. A further complication is that most military personnel are subjected to postings at regular intervals. The ADO's Directorate of Defence Occupational Health and Safety has established an Ionising Radiation Safety Subcommittee to monitor not only the adequacy of the internal Ionising Radiation Safety Manual but also the training requirements. A training course, responding to these requirements, has been developed to emphasise: basic radiation theory and protection; operation of radiation monitors available in the ADO; an understanding of the Safety Manual; day-to-day radiation safety in units and establishments; and appropriate responses to radiation accidents and emergencies. In addition, students are briefed on a limited number of peripheral topics and participate in some site visits. Currently, two Courses are held annually, each with about twenty students. Most of the material is presented by ADO personnel with external contractor support. The three Courses held to date have proved sufficiently successful, both for the students and the ADO generally, to seek national accreditation through the Australian National Training Authority and, as a first step, competency standards have been identified

  15. NICIL: Non-Ideal magnetohydrodynamics Coefficients and Ionisation Library

    Science.gov (United States)

    Wurster, James

    2016-08-01

    NICIL (Non-Ideal magnetohydrodynamics Coefficients and Ionisation Library) calculates the ionization values and the coefficients of the non-ideal magnetohydrodynamics terms of Ohmic resistivity, the Hall effect, and ambipolar diffusion. Written as a standalone Fortran90 module that can be implemented in existing codes, NICIL is fully parameterizable, allowing the user to choose which processes to include and decide the values of the free parameters. The module includes both cosmic ray and thermal ionization; the former includes two ion species and three species of dust grains (positively charged, negatively charged and neutral), and the latter includes five elements which can be doubly ionized.

  16. Use of ionising radiation for food processing applications

    International Nuclear Information System (INIS)

    Food irradiation is a recently developed technique used to sterilize and preserve food. Food products are exposed to ionising radiations such as X-rays, gamma rays or high energy electrons which destroy food borne pathogens and parasites and inhibit sprouting. Shelf life of food is extended. The following aspects of radiation processing of food are discussed in the monograph: radiation sources, choice of dose for specific results, safety and nutritional quality of radiation processed food, international status of acceptance of food irradiation, and cost. (M.G.B.). 6 tabs

  17. Ionisation constants of inorganic acids and bases in aqueous solution

    CERN Document Server

    Perrin, D D

    2013-01-01

    Ionisation Constants of Inorganic Acids and Bases in Aqueous Solution, Second Edition provides a compilation of tables that summarize relevant data recorded in the literature up to the end of 1980 for the ionization constants of inorganic acids and bases in aqueous solution. This book includes references to acidity functions for strong acids and bases, as well as details about the formation of polynuclear species. This text then explains the details of each column of the tables, wherein column 1 gives the name of the substance and the negative logarithm of the ionization constant and column 2

  18. Thermal ionisation mass spectrometry (TIMS): what, how and why?

    International Nuclear Information System (INIS)

    Thermal ionisation mass spectrometry (TIMS) is one of the oldest mass spectrometric techniques, which has been used for determining the isotopic composition and concentration of different elements using isotope dilution. In spite of the introduction of many other inorganic mass spectrometric techniques like spark source mass spectrometry (SSMS), glow discharge mass spectrometry (GDMS), inductively coupled plasma-mass spectrometry (ICP-MS), secondary ion mass spectrometry (SIMS), the TIMS technique plays the role of a definitive analytical methodology and still occupies a unique position in terms of its capabilities with respect to precision and accuracy as well as sensitivity

  19. Une source de rayonnement développée pour des mesures optiques de spectroscopie d'absorption large bande

    Science.gov (United States)

    Hong, D.; Sandolache, G.; Capelle, T.; Bauchire, J. M.; Le Menn, E.; Fleurier, C.

    2003-06-01

    Afin d'étudier la période post-arc et les gaz entourant l'arc électrique dans les disjoncteurs, une source de rayonnement large bande a été développée pour effectuer des mesures de spectroscopie d'absorption. La source a été étudiée afin de déterminer les meilleures conditions produisant un spectre intense et continu de rayonnement dans le domaine ultra-violet et également dans le visible. Des essais d'absorption ont été réalisés dans un disjoncteur basse tension de type rail. L'absorption des raies de résonance de cuivre (324.7 et 327.4 nm) a permis de déterminer la densité d'atomes de cuivre dans la région à l'arrière de l'arc. En outre, l'absorption des bandes de Swan de C2 a permis de déterminer la concentration de carbone et également la température cinétique du gaz chaud.

  20. Ionizing radiation sources: very diversified means, multiple applications and a changing regulatory environment. Conference proceedings; Les sources de rayonnements ionisants: des moyens tres diversifies, des applications multiples et une reglementation en evolution. Recueil des presentations

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-11-15

    This document brings together the available presentations given at the conference organised by the French society of radiation protection about ionizing radiation source means, applications and regulatory environment. Twenty eight presentations (slides) are compiled in this document and deal with: 1 - Overview of sources - some quantitative data from the national inventory of ionizing radiation sources (Yann Billarand, IRSN); 2 - Overview of sources (Jerome Fradin, ASN); 3 - Regulatory framework (Sylvie Rodde, ASN); 4 - Alternatives to Iridium radiography - the case of pressure devices at the manufacturing stage (Henri Walaszek, Cetim; Bruno Kowalski, Welding Institute); 5 - Dosimetric stakes of medical scanner examinations (Jean-Louis Greffe, Charleroi hospital of Medical University); 6 - The removal of ionic smoke detectors (Bruno Charpentier, ASN); 7 - Joint-activity and reciprocal liabilities - Organisation of labour risk prevention in case of companies joint-activity (Paulo Pinto, DGT); 8 - Consideration of gamma-graphic testing in the organization of a unit outage activities (Jean-Gabriel Leonard, EDF); 9 - Radiological risk control at a closed and independent work field (Stephane Sartelet, Areva); 10 - Incidents and accidents status and typology (Pascale Scanff, IRSN); 11 - Regional overview of radiation protection significant events (Philippe Menechal, ASN); 12 - Incident leading to a tritium contamination in and urban area - consequences and experience feedback (Laurence Fusil, CEA); 13 - Experience feedback - loss of sealing of a calibration source (Philippe Mougnard, Areva); 14 - Blocking incident of a {sup 60}Co source (Bruno Delille, Salvarem); 15 - Triggering of gantry's alarm: status of findings (Philippe Prat, Syctom); 16 - Non-medical electric devices: regulatory changes (Sophie Dagois, IRSN; Jerome Fradin, ASN); 17 - Evaluation of the dose equivalent rate in pulsed fields: method proposed by the IRSN and implementation test (Laurent Donadille, IRSN); 18 - Dosimetry in the environment of a ultra-high intensity laser (Jean-Marie Fauquant, Pascal Monot, CEA); 19 - Use of operational dosemeters in interventional radiology/cardiology: results of the Oramed European project (Isabelle Clairand, IRSN); 20 - Awareness-raising to nuclear materials protection and control among 'small owners' (David Ladsous, IRSN); 21 - Management of spent sealed sources (Bernard Sevestre, CEA); 22 - Preparation and implementation of a withdrawal plan for radioactive Overvoltage arresters (Robert Farejeaux, France Telecom); 23 - Radioactive sources transport Regulation (Gabriel Meyer, ASN); 24 - Status after 3 years of Camari examination (certificate of professional competence in the handling of industrial radiological devices) 2008-2011 (Jean-Pierre Vidal, IRSN) 25 - Approval of cases for the internal transport of calibration sources (Jean-Pierre Marcassoli, Areva); 26 - Use of measurement devices, except radiometers, for the technical and environmental radiation protection controls of sources and devices (Thierry Lahaye, DGT); 27 - Complexity of radiation protection controls of unaccessible sources (Philippe Tranchant, Technam Industrie); 28 - Isemir (Information System on Occupational Exposure in Medicine, Industry and Research) - Report from the working group on industrial radiography (Gonzague Abela, EDF)

  1. Etude expérimentale et modélisation Monte Carlo des grandeurs opérationnelles en métrologie des rayonnements ionisants : application à la dosimétrie neutrons par radiophotoluminescence

    OpenAIRE

    Salem, Youbba Ould

    2014-01-01

    Nous mettons au point un dosimètre passif capable de détecter les neutrons rapides et thermiques, destiné à la fois à la dosimétrie d'ambiance et personnelle. Ce dosimètre détecte les neutrons au moyen de convertisseurs appropriés (polyéthylène et cadmium). Cette étude s'est appuyée sur des simulations Monte Carlo, qui ont aidé à la conception géométrique du dosimètre et au choix des matériaux. La caractérisation expérimentale du dosimètre montre que les réponses à ces neutrons en termes de H...

  2. Étude de l’induction optique d’une émission laser DFB dans les scintillateurs organiques en vue d’une mesure active des rayonnements ionisants.

    OpenAIRE

    Michel, Maugan

    2014-01-01

    Transducers used for nuclear measurements are divided into two groups. The first one is made of detectors based on the movement of charged carriers created during the interaction of ionizing radiation with materials (ionization chambers, semiconductors, etc.). The second comprises scintillating materials which emit light following such interaction.The present work aims at shifting the current paradigm in order to achieve an active measurement of the interactions between particles and sensor. ...

  3. Evolution of the legislation concerning the professional diseases considered as produced by ionized radiation; Evolution de la legislation concernant les maladies professionnelles considerees comme provoquees par les rayonnements ionisants

    Energy Technology Data Exchange (ETDEWEB)

    Hebert, J

    2004-06-01

    After having remind the history and structure of the classical French system of compensation of occupational diseases, conditions put to insert such of these diseases induced by ionizing radiations are studied, before to conclude by an exam of solutions that a new system introduced by an act of 27 of January 1993 could offer in some situations. (author)

  4. Synthèse et évalutaion de nouveaux composés organiques et phosphorés contre les effets des rayonnements ionisants. Etude de leur mécanisme d'action in vitro.

    OpenAIRE

    Prouillac, C.

    2006-01-01

    This work falls under a research program. The aim was to synthesize new organic phosphorylated compounds having an interesting radiopharmacological activity without toxicity. That's why, we carried out the synthesis of new benzothiazole and thiadiazole N-substituted derivatives as thiols, aminothiols, acids thiosulfonic and phosphorothioates. All these compounds were characterized by NMR (proton, carbon, phosphorus, 2D), by mass spectrometry, elementary analyzes and for some of them by diffra...

  5. Biological monitors for low levels of ionising radiation

    International Nuclear Information System (INIS)

    The biological effects of high doses of ionising radiation are well understood and the methods of measurement of these doses well established. However the effects due to extremely low doses remain by and large uncertain. This is because of the fact that at such low doses no gross symptoms are seen. In fact, at these levels the occurrence of double strand breaks leading to the formation of chromosomal aberrations like dicentrics is rare and chances of mutation due to base damage are negligible. Hence neither chromosomal aberration studies nor mutational assays are useful for detecting doses of the order of a few milligray. Results of exhaustive work done by various laboratories indicate that below 20 mGy the chromosomal aberration technique based on scoring of dicentrics cannot distinguish between a linear or a threshold model. However indirect methods like unscheduled DNA synthesis (UDS) and sister chromatid exchanges (SCEs) appear to be promising for the detection of radiation exposures due to low levels of radiation. This report reviews the available literature on the biological effects of low levels of ionising radiation and highlights the merits and demerits of the various methods employed in the measurement of UDS and SCE. The phenomenon of radio-adaptive response (RAR) and its relation to DNA repair is also discussed. (author)

  6. Characterisation of bacteria by matrix-assisted laser desorption/ionisation and electrospray mass spectrometry

    NARCIS (Netherlands)

    Baar, B.L.M. van

    2000-01-01

    Chemical analysis for the characterisation of micro-organisms is rapidly evolving, after the recent advent of new ionisation methods in mass spectrometry (MS): electrospray (ES) and matrix-assisted laser desorption/ionisation (MALDI). These methods allow quick characterisation of micro-organisms, ei

  7. Formulas for ionization yield functions and ionisation capability of solar cosmic rays in the ionosphere and atmosphere

    International Nuclear Information System (INIS)

    The solar cosmic rays produced in solar flares (and in some other high energy solar processes) are one of the most important manifestations of solar activity and one of the main agents in solar-terrestrial relationships. Two approaches have been developed to compute the CR ionisation, e.g.: i ) the model CORIMIA – COsmic Ray Ionisation Model for Ionosphere and Atmosphere is analytical, while ii ) CORSIKA code, including the FLUKA Monte Carlo package is statistical; it is based on a Monte Carlo simulation of the atmospheric cascade. Usually the analytical models use the ionisation capability C function, while the statistical simulations utilize the ionisation yield Y function. In the present work formulas for ionisation capability C and ionisation yield functions Y are derived for the solar cosmic rays, i.e. for sub-relativistic approximation. Some practical applications are discussed. Key words: solar cosmic rays, iono/atmosphere system, ionisation capability, ionisation yield function

  8. Electron spectroscopy of He and NO using electron impact and multiphoton ionisation

    International Nuclear Information System (INIS)

    This thesis describes two experimental studies which are intended to contribute to our knowledge of the structure of molecules and the decay dynamics of excited molecular states. The two studies have in common that they are both concerned with ionisation processes, in which an accurately known amount of energy is transferred to the target, and energy analysis of the ejected electrons is made. Ionisation is caused either by scattering electrons off the molecules (chapter 2: electron impact ionisation) or by a simultaneous absorption of several photons (chapter 3: multiphoton ionisation). In chapter 2 an electron impact ionisation experiment on Helium is described in which the kinematics of both the scattered and the ejected electrons is fully determined ((e,2e) experiment). (Auth.)

  9. The use of detectors based on ionisation recombination in radiation protection

    International Nuclear Information System (INIS)

    Intitial recombination of ionisation in a gas depends on the ionisation density and hence on the linear energy transfer along the tracks of charged particles. This effect can be used as a basis for instruments that respond to different types of ionising radiation approximately in the way required by the quality factor-linear energy transfer relation recommended by the ICRP for use in radiation protection. Empirical instruments based on ionisation recombination that have been used for radiation protection measurements are reviewed, and relations are derived from recombination theory that show that the response of such detectors can be readily predicted. The usefulness of recombination instruments in radiation protection is discussed and their advantages and limitations assessed. It is shown that their main application will be as reference instruments against which other detectors can be calibrated. As an extension to using recombination detectors as reference instruments, the feasibility of specifying radiation quality in terms of ionisation recombination is investigated. (author)

  10. Studies of Non-Targeted Effects of Ionising Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Oleg V Belyakov; Heli Mononen; Marjo Peraelae [STUK - Radiation and Nuclear Safety Authority, Helsinki (Finland)

    2006-07-01

    The discovery of ionising radiation induced non-targeted effects is important for understanding the dose-response mechanisms relevant to low dose irradiation in vivo. One important question is whether the non-targeted effects relates to a protective mechanism or whether, conversely, it amplifies the number of cells damaged by the isolated radiation tracks of low dose exposures leading to an increased risk of carcinogenesis. One theory supported by the experimental data obtained during this project is that the main functions of the non-targeted effects are to decrease the risk of transformation in a multicellular organism exposed to radiation. Differences in the gene expression profiles, temporal and spatial patterns of key proteins expressed in directly irradiated and bystander cells may determine how the cells ultimately respond to low doses of radiation. Such a mechanism of co-operative response would make the tissue system much more robust. (N.C.)

  11. Protection of the environment from ionising radiation: ethical issues

    International Nuclear Information System (INIS)

    The paper identifies some of the main ethical issues concerning the protection of the environment from radiation and suggests ways in which ethics can aid in developing a system of protection. After a presentation of background on ethical theory and environmental ethics, three main issues related to practical environmental protection are discussed: First, the question of who or what has moral standing; second the appropriate level of protection; and third compatibility with other environmental stressors. In summary, the paper argues that there are strong ethical grounds for efforts to provide for the protection of the environment and that, all other things being equal, there is no reason to treat ionising radiation differently to other environmental stressors. (author)

  12. Caractérisation des paramètres d'interception du rayonnement par le pin d'Alep (Pinus halepensis Mill.)

    OpenAIRE

    Gillmann, Marion

    2009-01-01

    Les recherches sur les impacts des changements climatiques sur le bilan de carbone des écosystèmes forestiers nécessitent des modèles informatiques décrivant un grand nombre de processus, dont l'interception du rayonnement. Ce paramètre fait intervenir l'inclinaison et l'orientation des feuilles. Dans cette étude, les objectifs sont d'évaluer si chez le pin d'Alep, conifère très répandu dans les régions méditerranéennes, l'environnement lumineux, l'âge des aiguilles, et le type de rameau infl...

  13. Using ionising radiation against terrorism and contrabandism - dosimetric problems

    International Nuclear Information System (INIS)

    As will be explained in more detail in a talk at this conference, the personnel X-ray scanners can be divided into two groups, one using the transmitted X rays for image creation, the other one using the Compton back scatters X-rays. In the case of a backscatter scanner, a narrow, pencil -like X-ray beam is produced by a rotating chopper-wheel. The person/object is scanned in a raster scan pattern. The backscattered X-rays of all points are measured and recorded. The transmission X-ray scanner can use both fan-like and pencil like X-ray beams. The transmission detectors are installed behind the object and detect the absorption of the scanned person. Due to the very low dose values of the X-ray scanner systems in combination with a high dose rate in the direct beam for a short irradiation time, special dosemeters have to be used. In the literature and in manufacturers' specifications, the dose values given for some systems are in the range from 0.05 μSv to 5 μSv per scan with a typical irradiation time of a few milliseconds. Due to this pulse-like character of the radiation fields, the dose rate is several sieverts per hour. For the measurements of the investigated scanner, dosemeters were therefore needed having the capability to measure low doses at high dose rates and to measure in pulsed radiation fields. For the optimization of the measurements, the use of measuring devices with a direct indication is necessary. Ionisation chambers are the most suitable measuring instruments to fulfill these requirements. The difficulty for the measurements with an ionisation chamber is that the leakage charge integrated over time can reach values at the level of the expected radiation-produced charge. Additionally unpredictable variations of the leakage charge can be in the same order of magnitude as the expected signal. This challenge led to the development of a special electronics which allow the execution of time-resolved measurements. With this time resolution, it is

  14. Application of neural networks to measurement methods based on radiation interactions with matter; Application des reseaux de neurones aux methodes de mesure basees sur l'interaction rayonnement matiere

    Energy Technology Data Exchange (ETDEWEB)

    Pilato, V

    1999-07-01

    The possibility of improving by neuronal techniques the preparation and interpretation of nuclear measurements was investigated. A general methodology was developed and applied to various problems in this field. Whatever the problem to be treated, to solve it comes to determine the relation which binds the inputs to the outputs. Neural networks based on supervised training, like the multilayer Perceptron, have the capability to calculate any relation between a set of input and output data. On the other hand, the training phase is often a long and delicate operation whose difficulties grow with the size of the network:it is thus interesting to reduce it by introducing knowledge a priori and/or by reducing the number of inputs in order to extract the relevant information. If the correlations between the inputs are linear, the Principal Components Analysis (PCA) and its neuronal equivalents make it possible to obtain by orthogonal projection a reduced number of input components while preserving the maximum of initial information. If the correlations are nonlinear, the Curvilinear Components Analysis (CCA) allows, by a unsupervised training, to carry out a nonlinear projection of the inputs in a space of reduced size. Besides, it is noticed that when the dimension of the input space is equal to the intrinsic dimension of the problem, this last is practically solved by CCA. We propose a general method which consists in characterizing as well as possible the problem by its inputs and then to extract and classify the information contained in those by projection in a space of reduced size. Association between the projected data and the problem outputs is then carried out by a supervised training network. Certain results having to be provided with their associated uncertainty, a statistical method based on the bootstrap algorithm is proposed. Potential applications other that those treated are considered. (author)

  15. Electron impact ionisation cross sections of iron hydrogen clusters

    Science.gov (United States)

    Huber, Stefan E.; Sukuba, Ivan; Urban, Jan; Limtrakul, Jumras; Probst, Michael

    2016-09-01

    We computed electron impact ionisation cross sections (EICSs) of iron hydrogen clusters, FeHn with n = 1,2,...,10, from the ionisation threshold to 10 keV using the Deutsch-Märk (DM) and the binary-encounter-Bethe (BEB) formalisms. The maxima of the cross sections for the iron hydrogen clusters range from 6.13 × 10-16 cm2 at 60 eV to 8.76 × 10-16 cm2 at 76 eV for BEB-AE (BEB method based on quantum-chemical data from all-electron basis sets) calculations, from 4.15 × 10-16 cm2 at 77 eV to 7.61 × 10-16 cm2 at 80 eV for BEB-ECP (BEB method based on quantum-chemical data from effective-core potentials for inner-core electrons) calculations and from 2.49 × 10-16 cm2 at 43.5 eV to 7.04 × 10-16 cm2 at 51 eV for the DM method. Cross sections calculated via the BEB method are substantially higher than the ones obtained via the DM method, up to a factor of about two for FeH and FeH2. The formation of Fe-H bonds depopulates the iron 4s orbital, causing significantly lower cross sections for the small iron hydrides compared to atomic iron. Both the DM and BEB cross sections can be fitted perfectly against a simple expression used in modelling and simulation codes in the framework of nuclear fusion research. The energetics of the iron hydrogen clusters change substantially when exact exchange is present in the density functional, while the cluster geometries do not depend on this choice. Supplementary material in the form of one pdf file available from the Journal web page athttp://dx.doi.org/10.1140/epjd/e2016-70292-4

  16. Critical ionisation velocity and the dynamics of a coaxial plasma gun

    International Nuclear Information System (INIS)

    The dynamics of an ionising wave in a coaxial plasma gun with an azimuthal bias magnetic field is analysed in a theoretical model. Only the radial dependence is treated and instead of including a treatment of the energy balance two separate physical assumptions are made. In the first case it is assumed that the total internal electric field is given by the critical ionisation velocity condition and in the second that the ionisation rate is constant. For consistency wall sheaths are assumed to match the internal plasma potential to that of the walls. On the basis of momentum and particle balance the radial dependence of the electron density, current density, electric field and drift velocity are found. An electron source is required at the cathode and the relative contribution from ionisation within the plasma is deduced. The assumption that there are no ion sources at the electrodes leads to a restriction on the possible values of the axial electric field. (author)

  17. The Kelvin-Helmholtz instability in weakly ionised plasmas II: multifluid effects in molecular clouds

    OpenAIRE

    Jones, A. C.; Downes, T. P

    2011-01-01

    We present a study of the Kelvin-Helmholtz instability in a weakly ionised, multifluid MHD plasma with parameters matching those of a typical molecular cloud. The instability is capable of transforming well-ordered flows into disordered flows. As a result, it may be able to convert the energy found in, for example, bowshocks from stellar jets into the turbulent energy found in molecular clouds. As these clouds are weakly ionised, the ideal magnetohydrodynamic approximation does not apply at s...

  18. The potential use of ionising energy treatment in Queensland's horticultural industries

    International Nuclear Information System (INIS)

    The potential application of ionising energy treatment technology in Queensland falls into three categories: insect disinfestation, disease control and quality improvement. The technology fulfils the requirements of a disinfestation treatment against Queensland fruit fly and other pests of quarantine importance in respect to efficacy, absence of phytotoxicity, absence of residues and, on technical considerations would be an ideal replacement for the fumigant EDB. The report examines the purposes of ionising energy treatment, economic and marketing aspects and research needs

  19. Proceedings. Protection of the natural environment. International symposium on ionising radiation

    International Nuclear Information System (INIS)

    The symposium was organised jointly by the Swedish Radiation Protection Institute and the Atomic Energy Control Board of Canada. The programme was organised around six major topics: Biological effects of ionising radiation; Ecological effects of ionising radiation; Behaviour and transport of radionuclides in the natural environment; Criteria for environmental protection; Assessment methodology; and Social and economic aspects. All 86 contributions (excluding the opening addresses) have been separately indexed

  20. Evidence for Ionised Accretion Discs in Five Narrow-Line Seyfert 1 Galaxies

    CERN Document Server

    Ballantyne, D R; Fabian, A C

    2000-01-01

    (Abridged) We present the results of fitting ASCA spectra of six narrow-line Seyfert 1 (NLS1) galaxies with the ionised reflection models of Ross & Fabian (1993). We find that five of the galaxies (TONS 180, PKS 0558-504, Ark 564, Mrk 335 and PG 1244+026) are well fit by the ionised disc model, and these are often better fits than the alternative models considered. The sixth galaxy, NGC 4051, has additional spectral complexity that cannot be well described by a simple ionised disc model or any of the other alternative models. All six of the NLS1s we considered show evidence for a broad Fe Kalpha line, but none of the line centroids are consistent with emission from highly ionised Fe. This is most likely due to the line being redshifted because of relativistic effects. We note that sources with larger ionisation parameters tend to have larger Fe Kalpha EWs. We interpret this as evidence that ionised Fe features are making their presence felt in the spectra. Since most of our sources have steep spectra, hig...

  1. Individual response to ionising radiation: What predictive assay(s) to choose?; Reponse individuelle aux radiations ionisantes: quel(s) test(s) predictif(s) choisir?

    Energy Technology Data Exchange (ETDEWEB)

    Granzotto, A.; Viau, M.; Devic, C.; Maalouf, M.; Thomas, Ch.; Vogin, G.; Foray, N. [Inserm, U836, groupe de radiobiologie, institut des neurosciences, chemin Fortune-Ferrini, 38042 Grenoble (France); Granzotto, A.; Vogin, G.; Balosso, J. [Centre de hadrontherapie Etoile, 69008 Lyon (France); Joubert, A. [Societe Magelis, 84160 Cadenet (France); Maalouf, M. [Centre national d' etudes spatiales, 75001 Paris (France); Vogin, G.; Colin, C. [EA 3738, faculte de medecine, Lyon-Sud, 69921 Oullins (France); Malek, K.; Balosso, J. [Service de radiotherapie, CHU A.-Michallon, 38042 Grenoble (France); Colin, C. [Service de radiologie, CHU Lyon-Sud, 69490 Pierre-Benite (France)

    2011-02-15

    Individual response to ionizing radiation is an important information required to apply an efficient radiotherapy treatment against tumour and to avoid any adverse effects in normal tissues. In 1981, Fertil and Malaise have demonstrated that the post-irradiation local tumor control determined in vivo is correlated with clonogenic cell survival assessed in vitro. Furthermore, these authors have reminded the relevance of the concept of intrinsic radiosensitivity that is specific to each individual organ (Fertil and Malaise, 1981) [1]. To date, since clonogenicity assays are too time-consuming and do not provide any other molecular information, a plethora of research groups have attempted to determine the molecular bases of intrinsic radiosensitivity in order to propose reliable and faster predictive assays. To this aim, several approaches have been developed. Notably, the recent revolution in genomic and proteomics technologies is providing a considerable number of data but their link with radiosensitivity still remains to be elucidated. On another hand, the systematic screening of some candidate genes potentially involved in the radiation response is highlighting the complexity of the molecular and cellular mechanisms of DNA damage sensing and signalling and shows that an abnormal radiation response is not necessarily due to the impairment of one single protein. Finally, more modest approaches consisting in focusing some specific functions of DNA repair seem to provide more reliable clues to predict over-acute reactions caused by radiotherapy. In this review, we endeavored to analyse the contributions of these major approaches to predict human radiosensitivity. (authors)

  2. Dosimetry of ionising radiation in modern radiation oncology.

    Science.gov (United States)

    Kron, Tomas; Lehmann, Joerg; Greer, Peter B

    2016-07-21

    Dosimetry of ionising radiation is a well-established and mature branch of physical sciences with many applications in medicine and biology. In particular radiotherapy relies on dosimetry for optimisation of cancer treatment and avoidance of severe toxicity for patients. Several novel developments in radiotherapy have introduced new challenges for dosimetry with small and dynamically changing radiation fields being central to many of these applications such as stereotactic ablative body radiotherapy and intensity modulated radiation therapy. There is also an increasing awareness of low doses given to structures not in the target region and the associated risk of secondary cancer induction. Here accurate dosimetry is important not only for treatment optimisation but also for the generation of data that can inform radiation protection approaches in the future. The article introduces some of the challenges and highlights the interdependence of dosimetric calculations and measurements. Dosimetric concepts are explored in the context of six application fields: reference dosimetry, small fields, low dose out of field, in vivo dosimetry, brachytherapy and auditing of radiotherapy practice. Recent developments of dosimeters that can be used for these purposes are discussed using spatial resolution and number of dimensions for measurement as sorting criteria. While dosimetry is ever evolving to address the needs of advancing applications of radiation in medicine two fundamental issues remain: the accuracy of the measurement from a scientific perspective and the importance to link the measurement to a clinically relevant question. This review aims to provide an update on both of these. PMID:27351409

  3. Dedicated Trigger for Highly Ionising Particles at ATLAS

    CERN Document Server

    Katre, Akshay; The ATLAS collaboration

    2015-01-01

    In 2012, a novel strategy was designed to detect signatures of Highly Ionising Particles (HIPs) such as magnetic monopoles, dyons or Qballs with the ATLAS trigger system. With proton-proton collisions at a centre of mass enegy of 8 TeV, the trigger was designed to have unique properties as a tracker for HIPs. It uses only the Transition Radiation Tracker (TRT) system, applying an algorithm distinct from standard tracking ones. The unique high threshold readout capability of the TRT is used at the location where HIPs in the detector are looked for. In particular the number and the fraction of TRT high threshold hits is used to distinguish HIPs from background processes. The trigger requires significantly lower energy depositions in the electro-magnetic calorimeters as a seed unlike previously used trigger algorithms for such searches. Thus the new trigger is capable of probing a large range of HIP masses and charges. We will give a description of the algorithms for this newly developed trigger for HIP searches...

  4. Education and training issues in individual monitoring of ionising radiation

    International Nuclear Information System (INIS)

    The present article deals with the education and training (E and T) issues of individual monitoring (IM) of ionising radiation, based on the requirements provided by the Basic Safety Standards EURATOM Directive and the European Commission Technical Recommendations for IM of external radiation. The structure and the objectives of E and T programmes addressed to the staff of dosimetry services, in order to allow the recognition and ensure the continuity of expertise are discussed. The necessity for the establishment of a national strategy for building competence in IM through information, education, training and retraining programmes, addressed to the individually monitored personnel is underlined. The train the trainers' concept is recognised as being an important tool for optimising resources and transferring the skills necessary for building competence. The conditions under which an efficient train the trainers' approach can be established are discussed. Examples of curricula concerning the key persons involved in the provision of E and T in occupational radiation protection are also given. (authors)

  5. Dosimetry of ionising radiation in modern radiation oncology

    Science.gov (United States)

    Kron, Tomas; Lehmann, Joerg; Greer, Peter B.

    2016-07-01

    Dosimetry of ionising radiation is a well-established and mature branch of physical sciences with many applications in medicine and biology. In particular radiotherapy relies on dosimetry for optimisation of cancer treatment and avoidance of severe toxicity for patients. Several novel developments in radiotherapy have introduced new challenges for dosimetry with small and dynamically changing radiation fields being central to many of these applications such as stereotactic ablative body radiotherapy and intensity modulated radiation therapy. There is also an increasing awareness of low doses given to structures not in the target region and the associated risk of secondary cancer induction. Here accurate dosimetry is important not only for treatment optimisation but also for the generation of data that can inform radiation protection approaches in the future. The article introduces some of the challenges and highlights the interdependence of dosimetric calculations and measurements. Dosimetric concepts are explored in the context of six application fields: reference dosimetry, small fields, low dose out of field, in vivo dosimetry, brachytherapy and auditing of radiotherapy practice. Recent developments of dosimeters that can be used for these purposes are discussed using spatial resolution and number of dimensions for measurement as sorting criteria. While dosimetry is ever evolving to address the needs of advancing applications of radiation in medicine two fundamental issues remain: the accuracy of the measurement from a scientific perspective and the importance to link the measurement to a clinically relevant question. This review aims to provide an update on both of these.

  6. The Laboratory appraisal of ionisation chamber smoke detectors

    International Nuclear Information System (INIS)

    The present paper traces the development of the National Radiological Protection Board test programme for ionisation chamber smoke detectors, describes methods and summarises the results from the detectors which have been examined by NRPB. The results of dose rate and surface contamination measurements are included as well as data from the destructive testing programme. The 600degC fire test continues to produce the most interesting results especially concerning material incompatibility problems. Some source holder materials invariably cause loss of source integrity during a fire, as do certain methods of fixing the foil to the holder. In addition plastics containing certain fire retardants produce corrosive combustion products which cause loss of integrity of otherwise well-mounted sources. Fire tests at 1200degC were discontinued at an early stage in the programme since it was felt there was no additional information to be gained. As all detectors are now tested with respect to the NEA recommendations, the 1200degC incineration tests have been reinstated as part of the test programme. The criterion of failure relates to activity which becomes airborne rather than the total leakage concept which applies at the lower temperature. All the detectors submitted will ultimately be subjected to this test, and some preliminary results are presented here. (H.K.)

  7. Martian sub-surface ionising radiation: biosignatures and geology

    Directory of Open Access Journals (Sweden)

    J. M. Ward

    2007-07-01

    Full Text Available The surface of Mars, unshielded by thick atmosphere or global magnetic field, is exposed to high levels of cosmic radiation. This ionising radiation field is deleterious to the survival of dormant cells or spores and the persistence of molecular biomarkers in the subsurface, and so its characterisation is of prime astrobiological interest. Here, we present modelling results of the absorbed radiation dose as a function of depth through the Martian subsurface, suitable for calculation of biomarker persistence. A second major implementation of this dose accumulation rate data is in application of the optically stimulated luminescence technique for dating Martian sediments.

    We present calculations of the dose-depth profile in the Martian subsurface for various scenarios: variations of surface composition (dry regolith, ice, layered permafrost, solar minimum and maximum conditions, locations of different elevation (Olympus Mons, Hellas basin, datum altitude, and increasing atmospheric thickness over geological history. We also model the changing composition of the subsurface radiation field with depth compared between Martian locations with different shielding material, determine the relative dose contributions from primaries of different energies, and discuss particle deflection by the crustal magnetic fields.

  8. Application of ionising radiation to the pharmaceutical industry

    International Nuclear Information System (INIS)

    Pharmacons, commonly called 'Drugs', are subject to a many-sided procedure of development before they are released on the market and reach the patient. Again and again they are submitted to controls for safety reasons and at least seven (sometimes nine or ten) years pass before the active substance has made its way from chemistry through many trials with animals in experimental pathology and through the laboratories of the biochemistry department. Ionising radiation is used in each field of drug research as an additional method for obtaining information. In chemistry the structure of molecules can be detected by X-ray diffraction, and the active component elucidated. In the teratology section of experimental pathology the foetus just before delivery and newborn animals are X-rayed. This is in order to find out skeletal malformations that might have occurred during feeding of the substance in question during gestation. In biochemistry the pharmacon is labelled with a suitable radioactive isotope. Its way through the body can then be followed by measuring absorption rate, distribution, binding and elimination. It is also important to explore the influence of the drug on the organism and the reverse - how the pharmacon is influenced by the organism. This means examining the metabolites of the drug and the mechanism of action by means of serial auto-radiography and clearance or excretion studies. Gamma rays are employed for sterilisation of ointment tubes and vials just before filling. Sterilisation of the pharmacon is discussed. (author)

  9. The large-scale ionised outflow of CH Cygni

    CERN Document Server

    Corradi, R L M; Livio, M; Mampaso, A; Gonçalves, D R; Schwarz, H E; Corradi, Romano L.M.; Munari, Ulisse; Livio, Mario; Mampaso, Antonio; Goncalves, Denise R.

    2001-01-01

    HST and ground-based [OII} and [NII] images obtained from 1996 to 1999 reveal the existence of a ionised optical nebula around the symbiotic binary CH Cyg extending out to 5000 A.U. from the central stars. The observed velocity range of the nebula, derived from long-slit echelle spectra, is of 130 km/s. In spite of its complex appearence, the velocity data show that the basic morphology of the inner regions of the optical nebula is that of a bipolar (or conical) outflow extending nearly along the plane of the sky out to some 2000 A.U. from the centre. Even if the extension of this bipolar outflow and its position angle are consistent with those of the radio jet produced in 1984 (extrapolated to the time of our optical imagery), no obvious counterpart is visible of the original, dense radio bullets ejected by the system. We speculate that the optical bipolar outflow might be the remannt of the interaction of the bullets with a relatively dense circumstellar medium.

  10. Excitation and Ionisation dynamics in high-frequency plasmas

    Science.gov (United States)

    O'Connell, D.

    2008-07-01

    Non-thermal low temperature plasmas are widely used for technological applications. Increased demands on plasma technology have resulted in the development of various discharge concepts based on different power coupling mechanisms. Despite this, power dissipation mechanisms in these discharges are not yet fully understood. Of particular interest are low pressure radio-frequency (rf) discharges. The limited understanding of these discharges is predominantly due to the complexity of the underlying mechanisms and difficult diagnostic access to important parameters. Optical measurements are a powerful diagnostic tool offering high spatial and temporal resolution. Optical emission spectroscopy (OES) provides non-intrusive access, to the physics of the plasma, with comparatively simple experimental requirements. Improved advances in technology and modern diagnostics now allow deeper insight into fundamental mechanisms. In low pressure rf discharges insight into the electron dynamics within the rf cycle can yield vital information. This requires high temporal resolution on a nano-second time scale. The optical emission from rf discharges exhibits temporal variations within the rf cycle. These variations are particularly strong, in for example capacitively coupled plasmas (CCPs), but also easily observable in inductively coupled plasmas (ICPs), and can be exploited for insight into power dissipation. Interesting kinetic and non-linear coupling effects are revealed in capacitive systems. The electron dynamics exhibits a complex spatio-temporal structure. Excitation and ionisation, and, therefore, plasma sustainment is dominated through directed energetic electrons created through the dynamics of the plasma boundary sheath. In the relatively simple case of an asymmetric capacitively coupled rf plasma the complexity of the power dissipation is exposed and various mode transitions can be clearly observed and investigated. At higher pressure secondary electrons dominate the

  11. The Ionising Radiations Advisory Committee Open Meeting 10 October 2001

    International Nuclear Information System (INIS)

    Full text: The Ionising Radiations Advisory Committee (IRAC) held its first open meeting on 10 October 2001 in response to a request from the Health and Safety Commission (HSC) that all its advisory committees should follow the Commission's example and hold such meetings. Some of the other advisory committees have already held open meetings and others are planning to do so shortly. The aim of the meeting was to enable members of the public to meet IRAC members and to find out more about the Committee - how it worked and the type of issues it dealt with. The first two sessions were devoted to short presentations describing IRAC's work and influences, now and in the future, on radiation protection generally. The third session was a discussion forum. The agenda for the meeting and the presentations are posted on the web at: www.hse.gov.uk/foi/iracopen.htm. Each session of presentations was followed by questions of clarification and the third session of the meeting comprised an open forum. Many of the questions raised were not directly relevant to IRAC but, nevertheless, members provided brief responses and referred questions on to others as appropriate. One question had been notified in advance, asking whether members of IRAC agreed that it is now (regrettably) reasonably foreseeable that a loss of containment of radioactive material may occur at a nuclear facility as a result of impact by an aeroplane or by other hostile acts, and that this should be made clear in published guidance on REPPIR. This question was not within IRAC's remit. The Chairman of the Nuclear Safety Advisory Committee offered to take the question to the Committee's next meeting. Issues discussed included: Concerns that exposure to ionising radiation at low levels is more dangerous than is currently reflected in risk estimates. The European Parliament has adopted a resolution calling on the main international bodies, including the International Commission on Radiological Protection (ICRP), the

  12. Invasive oral cancer stem cells display resistance to ionising radiation.

    Science.gov (United States)

    Gemenetzidis, Emilios; Gammon, Luke; Biddle, Adrian; Emich, Helena; Mackenzie, Ian C

    2015-12-22

    There is a significant amount of evidence to suggest that human tumors are driven and maintained by a sub-population of cells, known as cancer stem cells (CSC). In the case of head and neck cancer, such cells have been characterised by high expression levels of CD44 cell surface glycoprotein, while we have previously shown the presence of two diverse oral CSC populations in vitro, with different capacities for cell migration and proliferation. Here, we examined the response of oral CSC populations to ionising radiation (IR), a front-line measure for the treatment of head and neck tumors. We show that oral CSC initially display resistance to IR-induced growth arrest as well as relative apoptotic resistance. We propose that this is a result of preferential activation of the DNA damagerepair pathway in oral CSC with increased activation of ATM and BRCA1, elevated levels of DNA repair proteins RAD52, XLF, and a significantly faster rate of DNA double-strand-breaks clearance 24 hours following IR. By visually identifying CSC sub-populations undergoing EMT, we show that EMT-CSC represent the majority of invasive cells, and are more radio-resistant than any other population in re-constructed 3D tissues. We provide evidence that IR is not sufficient to eliminate CSC in vitro, and that sensitization of CD44hi/ESAlow cells to IR, followed by secondary EMT blockade, could be critical in order to reduce primary tumor recurrence, but more importantly to be able to eradicate cells capable of invasion and distant metastasis.

  13. Evaluation of background ionising radiation levels within Gwagwalada town, Abuja

    International Nuclear Information System (INIS)

    The background ionising radiation levels within Gwagwalada Town, Abuja has been carried out using Atomtex 1117M Radiation Monitor. Readings were taken in twelve different locations. Twenty different readings were taken at each location and the mean equivalent dose rate was used to calculate the annual equivalent dose rate. A total of 240 measurements were taken across the 12 locations in the study Area. It was observed that the average dose equivalent varied from 0.105±0.008 μSv/h to 0.114±0.015μSv/h with a mean of 0.109±0.013 μSv/h. The mean value from Ungwan Bassa shows the highest equivalent dose rate while the equivalent dose rate from Phase 3 was the lowest. Ungwan Dodo, Ungwan Gwari recorded the second and third highest in-situ gamma radiation of 0.113±0.013 μSv/h and 0.112±0.012 μSv/h respectively. The result shows that the entire equivalent dose rates of all the locations were below the value of the Standard Background Radiation of 0.133 μSv/h. The study also revealed that the average annual equivalent dose rate is 0.192±0.005 mSv/y which is lower than the value of 1.0 mSv/yr averaged over five consecutive years according to the dose limit recommended by the International Commission on Radiological Protection (ICRP).

  14. Ionising radiations produced in the vicinity of a petawatt laser

    Energy Technology Data Exchange (ETDEWEB)

    Borne, F. [CEA Bruyeres le Chatel, Service de Protection contre les Rayonnements 91 (France); Marques, J.R. [Ecole Polytechnique, Lab. pour l' Utilisation des Lasers Intenses, 91 - Palaiseau (France)

    2006-07-01

    A previous experimental study dedicated to radiological characterization of an experimental chamber and surrounding areas of an high intensity laser facility (100-Terawatt regime) revealed significant levels of X ray, gamma and neutrons radiations under particular experimental conditions which can significantly increase while upgrading of the intensity and regime of the laser. In order to improve the knowledge of radiations produced by the new generation of peta watt lasers ( {approx_equal}1021 W/cm{sup 2}) and the associated radiation protection safety devices and shielding in these facilities, a numerical study has been performed using the parameters of the future peta watt laser facility in the Laboratory for the Use of Intense Lasers at Ecole Polytechnique (L.U.L.I. - Palaiseau - France). Based on simulations with the Monte Carlo code M.C.N.P.X., an analysis of doses induced by ionising radiations produced by Bremsstrahlung reactions and secondary reactions, respectively in the laser interaction target and in the vacuum chamber, has been investigated on different positions of the facility, in order to define and size the appropriate materials for protection against external exposure in this new type of plant. These results are benchmarked with previous numerical and experimental results obtained with similar input parameters of the V.U.L.C.A.N. facility at the C.L.R.C. Rutherford Appleton Laboratory (R.A.L. - Oxon - England). This benchmark shows good agreement between these different results. The aim of the present publication is to present and discuss these numerical results. (authors)

  15. Soja MON 87701 Résistant Aux Insectes

    OpenAIRE

    Canada, Publié par la Direction des aliments de Santé

    2014-01-01

    Santé Canada a avisé Monsanto Canada Inc. qu’il ne s’oppose pas à l’utilisation alimentaire du soja MON 87701 résistant aux insectes. Le Ministère a réalisé une évaluation approfondie de cette lignée de soja conformément aux Lignes directrices sur l’évaluation de l’innocuité des aliments nouveaux. Ces lignes directrices sont fondées sur les principes admis internationalement de l’établissement de l’innocuité d’aliments comportant des caractères nouveaux. Le texte qu...

  16. Solar Hard X-ray Source Sizes in a Beam-Heated and Ionised Chromosphere

    CERN Document Server

    O'Flannagain, A; Gallagher, P T

    2014-01-01

    Solar flare hard X-rays (HXRs) are produced as bremsstrahlung when an accelerated population of electrons interacts with the dense chromospheric plasma. HXR observations presented by using the Ramaty High-Energy Solar Spectroscopic Imager (RHESSI) have shown that HXR source sizes are 3-6 times more extended in height than those predicted by the standard collisional thick target model (CTTM). Several possible explanations have been put forward including the multi-threaded nature of flare loops, pitch-angle scattering, and magnetic mirroring. However, the nonuniform ionisation (NUI) structure along the path of the electron beam has not been fully explored as a solution to this problem. Ionised plasma is known to be less effective at producing nonthermal bremsstrahlung HXRs when compared to neutral plasma. If the peak HXR emission was produced in a locally ionised region within the chromosphere, the intensity of emission will be preferentially reduced around this peak, resulting in a more extended source. Due to...

  17. Electronic temperature measurement on the deca II plasma using the Bremsstrahlung; Mesure de la temperature electronique du plasma de deca II par etude du rayonnement de freinage

    Energy Technology Data Exchange (ETDEWEB)

    Dumas, A. [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1967-06-01

    The electronic temperature of the DECA II machine's plasma is determined by studying the Bremsstrahlung. Two types of detectors are used for this measurement, a set scintillator-photo-multiplicator and a photoelectric effect detector with a massive silver target. The method used is the classical 'absorbent method', The absorbents used are thin formvar foils whose thickness is between 600 and 12 500 angstrom. The measurements done in two different working conditions of the DECA II machine have given: Te {approx_equal} 200 eV in the first case and Te {approx_equal} 70 eV in the second case. (author) [French] Nous avons determine la temperature electronique du plasma de la machine DECA II par l'etude du rayonnement de freinage. Pour cette mesure nous avons utilise deux types de detecteurs: des ensembles scintillateur-photomultiplicateur et un detecteur a effet photoelectrique a cible massive en argent. La methode utilisee pour cette mesure est la classique methode des absorbants. Nous avons utilise des feuilles de format tres mince (de 600 a 12 500 angstrom) comme absorbant. Les mesures faites dans deux regimes de travail differents de la machine DECA II nous ont conduit a: Te {approx_equal} 200 eV dans un cas et Te {approx_equal} eV dans l'autre cas. (auteur)

  18. Coupled-channel calculations of K-shell ionisation in asymmetric collision systems

    Energy Technology Data Exchange (ETDEWEB)

    Mehler, G.; Greiner, W.; Soff, G.

    1987-06-28

    Theoretical results on K-shell ionisation for a variety of asymmetric collision systems are reported. The calculated ionisation rates are compared with experimental data. The coupled-channel formalism underlying these calculations is presented. It is based on a set of relativistic target centred states, taking a screened potential of Dirac-Fock-Slater type into account. The effects of different matrix elements are discussed, e.g. continuum-continuum couplings. The binding effect is inherently contained in the present approach and described in a dynamical way.

  19. Tools to discover anionic and nonionic polyfluorinated alkyl surfactants by liquid chromatography electrospray ionisation mass spectrometry

    DEFF Research Database (Denmark)

    Trier, Xenia; Granby, Kit; Christensen, Jan H.

    2011-01-01

    A tiered approach is proposed for the discovery of unknown anionic and nonionic polyfluorinated alkyl surfactants (PFASs) by reversed phase ultra high performance liquid chromatography (UHPLC) – negative electrospray ionisation – quadrupole time of flight mass spectrometry (UHPLC......–ESI−–QTOF–MS). The chromatographic separation, ionisation and detection of PFASs mixtures, was achieved at high pH (pH=9.7) with NH4OH as additive. To distinguish PFASs from other chemicals we used the characteristic negative mass defects of PFASs, their specific losses of 20Da (HF) and the presence of series of chromatographic...

  20. Bolometer's development, with simultaneous measurement of heat and ionisation signals, at Saclay

    OpenAIRE

    Yvon, D.; Wang, N; Chapellier, M.; Chardin, G.; Levêque, P.; L'Hote, D.; Pari, P.; Soudée, J.; Guerrier, G.

    1993-01-01

    We report the latest developments of our work on bolometers. Low noise readout simultaneously in charge and heat channel was achieved. Tests were conducted using a 7g bolometer build in Berkeley. Baseline widths 350eV $ (1\\sigma , $ phonon) and 1keV $ (1\\sigma , $ ionisation) were measured. But the 60keV phonon width was found to be significantly larger than the baseline width. Also the amplitude of ionisation signal was found to drift with time. This effect motivated a detailed study of ioni...

  1. Ionisation of hydrogen-like atoms by a multiphoton absorption process

    International Nuclear Information System (INIS)

    The general expression for the amplitude of the probability of ionisation by a multiphoton absorption process is derived. Its non-relativistic limit is taken and the bipolar approximation is used for calculating the ionisation cross-section of hydrogen-like atoms. This latter involves the summation over intermediate virtual states by means of: a) a recursion relationship concerning angular functions, b) a particular technique which when applied to radial functions makes it possible to solve a system of inhomogeneous first-order differential equations. (authors)

  2. Non-dissociative and dissociative ionisation of H sub 2 by 50-2000 keV antiprotons

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, L.H.; Hvelplund, P.; Knudsen, H.; Moeller, S.P.; Pedersen, J.O.P.; Tang-Petersen, S.; Uggerhoej, E. (Aarhus Univ. (Denmark). Inst. of Physics); Elsener, K. (European Organization for Nuclear Research, Geneva (Switzerland)); Morenzoni, E. (Paul Scherrer Inst. (PSI), Villigen (Switzerland))

    1990-08-14

    A beam of antiprotons with energies between 50 keV and 2 MeV has been used for measurements of non-dissociative ionisation and dissociative ionisation cross sections of H{sub 2}. The results are compared with cross sections for equivelocity protons and electrons, and the role of interference effects in two-electron processes is discussed. (author).

  3. Genome-Wide Analysis and Characterization of Aux/IAA Family Genes in Brassica rapa

    OpenAIRE

    Paul, Parameswari; Dhandapani, Vignesh; Rameneni, Jana Jeevan; Li, Xiaonan; Sivanandhan, Ganesan; Choi, Su Ryun; Pang, Wenxing; Im, Subin; Lim, Yong Pyo

    2016-01-01

    Auxins are the key players in plant growth development involving leaf formation, phototropism, root, fruit and embryo development. Auxin/Indole-3-Acetic Acid (Aux/IAA) are early auxin response genes noted as transcriptional repressors in plant auxin signaling. However, many studies focus on Aux/ARF gene families and much less is known about the Aux/IAA gene family in Brassica rapa (B. rapa). Here we performed a comprehensive genome-wide analysis and identified 55 Aux/IAA genes in B. rapa usin...

  4. Sexe et pouvoir aux États-Unis

    OpenAIRE

    Mokhtar BEN BARKA

    2012-01-01

    Les adversaires politiques de Bill Clinton aiment à dire que l’Histoire se souviendra de lui plus à cause de ses mensonges et de sa sexualité débordante qu’en raison de son bilan. En vérité, les frasques sexuelles du président Clinton ne sont que la perpétuation d’une tradition qui remonte aux origines de la nation américaine. “Long before there was a United States of America”, écrit Shelley Ross, “there was sex, scandal, and corruption in American politics. In fact, some of the most notoriou...

  5. No evidence for large-scale outflows in the extended ionised halo of ULIRG Mrk273

    CERN Document Server

    Spence, R A W; Tadhunter, C N; Rose, M; Cabrera-Lavers, A; Spoon, H; Munoz-Tunon, C

    2016-01-01

    We present deep new GTC/OSIRIS narrow-band images and optical WHT/ISIS long-slit spectroscopy of the merging system Mrk273 that show a spectacular extended halo of warm ionised gas out to a radius of $\\sim45$ kpc from the system nucleus. Outside of the immediate nuclear regions (r > 6 kpc), there is no evidence for kinematic disturbance in the ionised gas: in the extended regions covered by our spectroscopic slits the emission lines are relatively narrow (FWHM $\\lesssim$ 350 km$\\rm s^{-1}$) and velocity shifts small (|$\\Delta$V| $\\lesssim{} $250 km$\\rm s^{-1}$). This is despite the presence of powerful near-nuclear outflows (FWHM > 1000 km$\\rm s^{-1}$; |$\\Delta$V| > 400 km$\\rm s^{-1}$; r < 6 kpc). Diagnostic ratio plots are fully consistent with Seyfert 2 photo-ionisation to the NE of the nuclear region, however to the SW the plots are more consistent with low-velocity radiative shock models. The kinematics of the ionised gas, combined with the fact that the main structures are aligned with low-surface-bri...

  6. Ionisation of Rydberg hydrogen atom near a metal surface by short pulse laser

    Institute of Scientific and Technical Information of China (English)

    Wang Lei; Yang Hai-Feng; Liu Xiao-Jun; Liu Hong-Ping

    2010-01-01

    In the ionisation of Rydberg hydrogen atoms near a metal surface,the electron will escape from the nucleus and arrive at the detector in a time sequence.This probability flux train relies on the initial electron wave packet irradiated by the laser pulse.For simplicity,the laser pulse is usually simplified to a delta function in energy domain,resulting in a sharp initial arrival time with an exponentially decaying tail at the detector.Actually and semiclassically,the initial outgoing wave should be modeled as an ensemble of trajectories propagating away from the atomic core in all directions with a range of launch times and a range of energies.In this case,each pulse in the pulse train is averaged out rather than a sharp profile.We examine how energy and time averaging of the electron wave packet affects the resolution of escaping electron pulses and study the energy dependence of the arrival time for each pulse in the ionisation train.An optimization condition for the laser pulse shape to generate narrow ionisation electron pulse in the train is obtained.The ionisation rates with various excitation energy are calculated also,which show the excitation to higher N Rydberg states will narrow the electron pulse as well.

  7. Calculated ionisation potentials to determine the oxidation of vanillin precursors by lignin peroxidase.

    NARCIS (Netherlands)

    ten Have, R.; Rietjens, I.M.C.M.; Hartmans, S.; Swarts, H.J.; Field, J.A.

    1998-01-01

    In view of the biocatalytic production of vanillin, this research focused on the lignin peroxidase (LiP) catalysed oxidation of naturally occurring phenolic derivatives: O-methyl ethers, O-acetyl esters, and O-glucosyl ethers. The ionisation potential (IP) of a series of model compounds was calculat

  8. Calculations of electron-impact ionisation of {{Fe}}^{25+} and {{Fe}}^{24+}

    Science.gov (United States)

    Fursa, Dmitry V.; Bostock, Christopher J.; Bray, Igor; Fontes, Christopher J.

    2016-09-01

    Electron-impact ionisation cross sections for the hydrogen- and helium-like ions of iron are calculated. The convergent close-coupling and distorted-wave methods in the relativistic and nonrelativistic formulations are used. The cross sections are in very good agreement with the results of the corresponding methods, with the relativistic formulation establishing the benchmarks to few percent accuracy.

  9. International responsability of state by the deleterius effects of ionising radiation

    International Nuclear Information System (INIS)

    International Responsability of State, considering the deleterius effects of ionising radiation on the human being, property, territory and environment which are under other jurisdiction, is focused. Conventional rules, costumary rules, the evolution of ''opinion juris'' as well as the decisions of tribunals related to the subject are analysed. (author)

  10. Bioaerosol detection by aerosol TOF-mass spectrometry: Application of matrix assisted laser desorption/ionisation

    NARCIS (Netherlands)

    Wuijckhuijse, A.L. van; Stowers, M.A.; Kientz, Ch.E.; Marijnissen, J.C.M.; Scarlett, B.

    2000-01-01

    In previous publications the use of an aerosol time of flight mass spectrometer was reported for the on-line measurements of aerosols (Weiss 1997, Kievit 1995). The apparatus is capable of measuring the size as well as the chemical composition, by the use of Laser Desorption/Ionisation (LDI), of an

  11. Destruction of Raman biosignatures by ionising radiation and the implications for life detection on Mars.

    Science.gov (United States)

    Dartnell, Lewis R; Page, Kristian; Jorge-Villar, Susana E; Wright, Gary; Munshi, Tasnim; Scowen, Ian J; Ward, John M; Edwards, Howell G M

    2012-04-01

    Raman spectroscopy has proven to be a very effective approach for the detection of microorganisms colonising hostile environments on Earth. The ExoMars rover, due for launch in 2018, will carry a Raman laser spectrometer to analyse samples of the martian subsurface collected by the probe's 2-m drill in a search for similar biosignatures. The martian surface is unprotected from the flux of cosmic rays, an ionising radiation field that will degrade organic molecules and so diminish and distort the detectable Raman signature of potential martian microbial life. This study employs Raman spectroscopy to analyse samples of two model organisms, the cyanobacterium Synechocystis sp. PCC 6803 and the extremely radiation resistant polyextremophile Deinococcus radiodurans, that have been exposed to increasing doses of ionising radiation. The three most prominent peaks in the Raman spectra are from cellular carotenoids: deinoxanthin in D. radiodurans and β-carotene in Synechocystis. The degradative effect of ionising radiation is clearly seen, with significant diminishment of carotenoid spectral peak heights after 15 kGy and complete erasure of Raman biosignatures by 150 kGy of ionising radiation. The Raman signal of carotenoid in D. radiodurans diminishes more rapidly than that of Synechocystis, believed to be due to deinoxanthin acting as a superior scavenger of radiolytically produced reactive oxygen species, and so being destroyed more quickly than the less efficient antioxidant β-carotene. This study highlights the necessity for further experimental work on the manner and rate of degradation of Raman biosignatures by ionising radiation, as this is of prime importance for the successful detection of microbial life in the martian near subsurface.

  12. OVER- EXPRESSION OF AN AUX1 HOMOLOG TRIGGERS OVARY INITIATION IN VITRO OF POPULUS TOMENTOSA CARR.

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    PtAUX1, an ortholog of Arabidopsis AtAUX1 ( encoding auxin influx carrier protein), has been cloned from Populus tomentosa. PtAUX1 protein is similar to Arabidopsis AtAUX1 in structure, but PtAUX1 contains an additional cAMP/cGMP - dependent protein kinase phosphorylation site. Its overexpression lines driven by 35S promoter exhibits a novel phenotype related flower development which has not been revealed in AtAUX1 mutants. Ovary - like structures each with 1 ~ 2 styles, but without a cup - like disc and a bract, can initial from regenerated transgenic bud in cluster,resembling an inflorescence. The histological dissections illuminate that the ovary - like structures have womb and transmitting tissue inner its styles, but no ovules. PtAUX1 expression pattern are ubiquitous and various in different organs,which is coincident with its candidate auxin influx, functioning in distributing auxin thorough a plant body. These results suggest that PtAUX1 or polar auxin transport has a substantial function in floral organ initiation.

  13. HCO+ and N2H+ as ionisation tracers in the low-mass protostar IRAS16293-2422

    Science.gov (United States)

    Quénard, D.; Bottinelli, S.; Caux, E.

    2016-05-01

    Ionisation in the molecular environment of star-forming regions gives important clues on the chemical processes that take place in the environment of a young protostar. Ionisation can be traced with molecules like HCO+ and N2H+ and it regulates the formation of larger molecules such as complex organic molecules (COMs). The ionisation degree can also play an important role in the free-fall timescale of the protostar since it prevents the neutral material to collapse through collisions with ions and electrons bound to the magnetic field of the central protostar.

  14. Study of the mechanism of direct laser desorption/ionisation for some small organic molecules (M < 400 Daltons).

    Science.gov (United States)

    Benazouz; Hakim; Debrun; Strivay; Weber

    1999-12-15

    Aspects of direct laser desorption/ionisation have been studied for three molecules, aminotriazole (positive ion), dinoterb and ioxynil (negative ion). The samples are deposited on metallic substrates, and a nitrogen laser is used for desorption/ionisation; ion yields are measured with a time-of-flight mass spectrometer. Previous work had shown that ion yields can strongly vary from one substrate to another, and that this variation does not reflect the (calculated) metal surface temperatures. New results obtained in this work indicate that the desorption/ionisation mechanism is linked to the physical state of the substrate surface. Copyright 1999 John Wiley & Sons, Ltd. PMID:10567927

  15. Shakespeare Cliff, rempart symbolique aux portes du royaume

    Directory of Open Access Journals (Sweden)

    Jeremy Price

    2006-02-01

    Full Text Available Figure 1 : Clarkson STANFIELD, Shakespeare Cliff, Dover, 1849, 1862« Il est une falaise, dont le front haut et courbeRegarde avec effroi dans l’abîme qu’elle enserre :Conduis-moi jusqu’à son bordEt je remédierai à la misère que tu souffresPar quelque riche objet ; de cet endroitJe n’aurai point besoin de guide. »Les lignes ci-dessus, tirées de l’Acte IV, Scène I du Roi Lear, font allusion aux falaises de Douvres, plus particulièrement à leur point culminant, un grand bloc de calcaire et de cr...

  16. Feticismo e desiderio in Poulet aux prunes di Marjane Satrapi

    Directory of Open Access Journals (Sweden)

    Stefania Rimini

    2013-05-01

    Full Text Available Il saggio si propone di individuare e descrivere le sfumature erotiche e sentimentali del film Poulet aux prunes di Marjane Satrapi, felice adattamento dell’omonima graphic novel. Il racconto procede per scarti, ellissi, anticipazioni e flasback, dando luogo a una narrazione labirintica dalla singolare trama arabescante. Le sottili dinamiche seduttive messe in campo dal complesso stile di regia di Satrapi-Paronnaud vengono analizzate alla luce delle categorie feticistiche individuate da Massimo Fusillo, che offrono interessanti modelli di interazione fra desiderio e creatività. L’esito di tale indagine consente di ampliare il dibattito relativo al rapporto di scambio e interferenza fra oggetti, pulsioni e sguardi nel cinema contemporaneo.

  17. Le date rape aux États-Unis

    OpenAIRE

    Fassin, Éric

    2013-01-01

    Pour appréhender une culture, on peut partir, non des représentations partagées, mais des polémiques qui la déchirent. Ainsi du date rape aux États-Unis, invention du féminisme universitaire et médiatique des années 1980 : en posant la question de la violence au cœur des rapports amoureux, le féminisme impose moins une orthodoxie qu’il ne propose une interprétation, doublement contestée durant les années quatre-vingt-dix par les intellectuels conservateurs et les essayistes « post-féministes ...

  18. Sexe et pouvoir aux États-Unis

    Directory of Open Access Journals (Sweden)

    Mokhtar BEN BARKA

    2003-06-01

    Full Text Available Les adversaires politiques de Bill Clinton aiment à dire que l’Histoire se souviendra de lui plus à cause de ses mensonges et de sa sexualité débordante qu’en raison de son bilan. En vérité, les frasques sexuelles du président Clinton ne sont que la perpétuation d’une tradition qui remonte aux origines de la nation américaine. “Long before there was a United States of America”, écrit Shelley Ross, “there was sex, scandal, and corruption in American politics. In fact, some of the most notoriou...

  19. Application de la combustion catalytique aux turbines à gaz

    Science.gov (United States)

    Lebas, E.; Martin, G. H.

    2002-04-01

    La réduction des émissions d'oxydes d'azote sur turbines à gaz est obtenue par diminution de la température au sein de la chambre de combustion. Les techniques possibles comprennent l'injection d'eau ou de vapeur, la combustion pauvre et l'oxydation catalytique. Parmi celles-ci, la dernière est la plus prometteuse en terme de coûts et de performances, avec des émissions de NOx ramenées à un seul chiffre (typiquement inférieures à 3 ppm). L'IFP travaille depuis maintenant 10 ans sur l'adaptation de la combustion catalytique aux turbines à gaz. Les études ont été conduites au travers de projets européen tels que AGATA (Advance Gas Turbine for Automotive Application) et ULECAT (Ultra Low CATalytic combustor for dual fuel gas turbine). Le premier projet était destiné au développement de véhicules hybrides et le second à la combustion stationnaire de biogaz et de combustible Diesel. Les études en cours dans ce domaine portent sur le développement d'une unité de cogénération intégrant une microturbine à combustion catalytique. Les travaux menés à l'IFP concernent la mise au point de catalyseurs répondant aux exigences de la combustion catalytique en turbine à gaz et le développement de chambres de combustion permettant la mise en oeuvre de ces catalyseurs.

  20. Ionisation and discharge in cloud-forming atmospheres of brown dwarfs and extrasolar planets

    CERN Document Server

    Helling, Ch; Rodriguez-Barrera, I M; Wood, Kenneth; Robertson, G B; Stark, C R

    2016-01-01

    Brown dwarfs and giant gas extrasolar planets have cold atmospheres with a rich chemical compositions from which mineral cloud particles form. Their properties, like particle sizes and material composition, vary with height, and the mineral cloud particles are charged due to triboelectric processes in such dynamic atmospheres. The dynamics of the atmospheric gas is driven by the irradiating host star and/or by the rotation of the objects that changes during its lifetime. Thermal gas ionisation in these ultra-cool but dense atmospheres allows electrostatic interactions and magnetic coupling of a substantial atmosphere volume. Combined with a strong magnetic field $\\gg B_{\\rm Earth}$, a chromosphere and aurorae might form as suggested by radio and X-ray observations of brown dwarfs. Non-equilibrium processes like cosmic ray ionisation and discharge processes in clouds will increase the local pool of free electrons in the gas. Cosmic rays and lighting discharges also alter the composition of the local atmospheri...

  1. Exploring the Powerful Ionised Wind in the Seyfert Galaxy PG1211+143

    Science.gov (United States)

    Pounds, Ken

    2013-10-01

    Highly-ionised high-speed winds in AGN (UFOs) were first detected with XMM-Newton a decade ago, and are now established as a key factor in the study of SMBH accretion, and in the growth and metal enrichment of their host galaxies. However, information on the ionisation and dynamical structure, and the ultimate fate of UFOs remains very limited. We request a 600ks extended XMM-Newton study of the prototype UFO PG1211+143 in AO-13, to obtain high quality EPIC and RGS spectra, to map the flow structure and variability, while seeking evidence for the anticipated interaction with the ISM and possible conversion of the energetic wind to a momentum-driven flow.

  2. Non-targeted effects of ionising radiation—Implications for low dose risk

    DEFF Research Database (Denmark)

    Kadhim, Munira; Salomaa, Sisko; Wright, Eric;

    2013-01-01

    with respect to systemic (human health) consequences at low and intermediate doses of ionising radiation. Other outstanding questions include links between the different non-targeted responses and the variations in response observed between individuals and cell lines, possibly a function of genetic background....... Furthermore, it is still not known what the initial target and early interactions in cells are that give rise to non-targeted responses in neighbouring or descendant cells. This paper provides a commentary on the current state of the field as a result of the non-targeted effects of ionising radiation (NOTE......) Integrated Project funded by the European Union. Here we critically examine the evidence for non-targeted effects, discuss apparently contradictory results and consider implications for low-dose radiation health effects. © 2012 Elsevier B.V. All rights reserved....

  3. Constraints on ionising photon production from the large-scale Lyman-alpha forest

    CERN Document Server

    Pontzen, Andrew; Peiris, Hiranya; Verde, Licia

    2014-01-01

    Recent work has shown that the z~2.5 Lyman-alpha forest on large scales encodes information about the galaxy and quasar populations that keep the intergalactic medium photoionized. We present the first forecasts for constraining the populations with data from current and next-generation surveys. At a minimum the forest should tell us whether galaxies or, conversely, quasars dominate the photon production. The number density and clustering strength of the ionising sources might be estimated to sub-10% precision with a DESI-like survey if degeneracies (e.g., with the photon mean-free-path, small-scale clustering power normalization and potentially other astrophysical effects) can be broken by prior information. We demonstrate that, when inhomogeneous ionisation is correctly handled, constraints on dark energy do not degrade.

  4. Positron-impact ionisation of atomic hydrogen in the presence of a bichromatic laser field

    Institute of Scientific and Technical Information of China (English)

    Lou Jun; Li Shu-Min

    2010-01-01

    The positron impact-ionisation of atomic hydrogen in the presence of a linearly polarised bichromatic field is investigated in the first Born approximation.The field is composed of a fundamental frequency and its second harmonic.The state of positron in the field is described by the Volkov wavefunction,and the continuum state of the ejected electron is described by the Coulomb-Volkov wavefunction.The dressed ground state of target is a first order time-dependent perturbative wavefunction.The triple differential cross sections and their dependencies on laser field parameters are discussed and compared with the results modified by a monochromatic field.Numerical results show that the coherent phase control is significant and the laser-assisted ionisation cross sections caused by positron and electron are different.

  5. Influence of ionising radiation on macromolecular components of wheat; possible use in detecting irradiated wheat

    Energy Technology Data Exchange (ETDEWEB)

    Jabir, A.-W.Sh.

    1992-01-01

    The treatment of food by ionising radiation is already permitted by many governments and is under consideration by many others. Cereal are irradiated as a means of disinfestation, this study investigates the effects of such processing on the components of wheat and examines using such radiation induced changes to detect irradiation. Wheat has been irradiated with ionising radiation in the dose range up to 1 kGy. The rheological properties of doughs prepared from this irradiated wheat have been investigated. An immunological assay has been employed to investigate the effect of wheat irradiation on the integrity of gliadin. A method has been developed for the routine isolation of DNA from wheat. Radiation-induced disruption of the DNA double helix has been assessed in DNA extracted from irradiated wheat and calf thymus DNA irradiated in aqueous solution. (author).

  6. An important step forward in continuous spectroscopic imaging of ionising radiations using ASICs

    CERN Document Server

    Fessler, P; Eberle, H; Raad-Iseli, C D; Hilt, B; Huss, D; Krummenacher, F; Lutz, Jean Robert; Prevot, G; Renouprez, Albert Jean; Sigward, M H; Schwaller, B; Voltolini, C

    1999-01-01

    Characterization results are given for an original ASIC allowing continuous acquisition of ionising radiation images in spectroscopic mode. Ionising radiation imaging in general and spectroscopic imaging in particular must primarily be guided by the attempt to decrease statistical noise, which requires detection systems designed to allow very high counting rates. Any source of dead time must therefore be avoided. Thus, the use of on-line corrections of the inevitable dispersion of characteristics between the large number of electronic channels of the detection system, shall be precluded. Without claiming to achieve ultimate noise levels, the work described is focused on how to prevent good individual acquisition channel noise performance from being totally destroyed by the dispersion between channels without introducing dead times. With this goal, we developed an automatic charge amplifier output voltage offset compensation system which operates regardless of the cause of the offset (detector or electronic). ...

  7. OsAUX1 controls lateral root initiation in rice (Oryza sativa L.).

    Science.gov (United States)

    Zhao, Heming; Ma, Tengfei; Wang, Xin; Deng, Yingtian; Ma, Haoli; Zhang, Rongsheng; Zhao, Jie

    2015-11-01

    Polar auxin transport, mediated by influx and efflux transporters, controls many aspects of plant growth and development. The auxin influx carriers in Arabidopsis have been shown to control lateral root development and gravitropism, but little is known about these proteins in rice. This paper reports on the functional characterization of OsAUX1. Three OsAUX1 T-DNA insertion mutants and RNAi knockdown transgenic plants reduced lateral root initiation compared with wild-type (WT) plants. OsAUX1 overexpression plants exhibited increased lateral root initiation and OsAUX1 was highly expressed in lateral roots and lateral root primordia. Similarly, the auxin reporter, DR5-GUS, was expressed at lower levels in osaux1 than in the WT plants, which indicated that the auxin levels in the mutant roots had decreased. Exogenous 1-naphthylacetic acid (NAA) treatment rescued the defective phenotype in osaux1-1 plants, whereas indole-3-acetic acid (IAA) and 2,4-D could not, which suggested that OsAUX1 was a putative auxin influx carrier. The transcript levels of several auxin signalling genes and cell cycle genes significantly declined in osaux1, hinting that the regulatory role of OsAUX1 may be mediated by auxin signalling and cell cycle genes. Overall, our results indicated that OsAUX1 was involved in polar auxin transport and functioned to control auxin-mediated lateral root initiation in rice.

  8. Constitutive auxin response in Physcomitrella reveals complex interactions between Aux/IAA and ARF proteins.

    Science.gov (United States)

    Lavy, Meirav; Prigge, Michael J; Tao, Sibo; Shain, Stephanie; Kuo, April; Kirchsteiger, Kerstin; Estelle, Mark

    2016-01-01

    The coordinated action of the auxin-sensitive Aux/IAA transcriptional repressors and ARF transcription factors produces complex gene-regulatory networks in plants. Despite their importance, our knowledge of these two protein families is largely based on analysis of stabilized forms of the Aux/IAAs, and studies of a subgroup of ARFs that function as transcriptional activators. To understand how auxin regulates gene expression we generated a Physcomitrella patens line that completely lacks Aux/IAAs. Loss of the repressors causes massive changes in transcription with misregulation of over a third of the annotated genes. Further, we find that the aux/iaa mutant is blind to auxin indicating that auxin regulation of transcription occurs exclusively through Aux/IAA function. We used the aux/iaa mutant as a simplified platform for studies of ARF function and demonstrate that repressing ARFs regulate auxin-induced genes and fine-tune their expression. Further the repressing ARFs coordinate gene induction jointly with activating ARFs and the Aux/IAAs. PMID:27247276

  9. Three-Dimensional S-Matrix Simulation of Single-Electron Resonant Tunnelling Through Random Ionised Donor States

    OpenAIRE

    Mizuta, Hiroshi

    1998-01-01

    This paper presents a numerical study of single-electron resonant tunnelling (RT) assisted by a few ionised donors in a laterally-confined resonant tunnelling diode (LCRTD). The 3D multi-mode S-matrix simulation is performed newly introducing the scattering potential of discrete impurities. With a few ionised donors being placed, the calculated energy-dependence of the total transmission rate shows new resonances which are donor-configuration dependent. Visualised electron probability density...

  10. Three-dimensional S-matrix simulation of single-electron resonant tunnelling through random ionised donor states

    OpenAIRE

    Hiroshi Mizuta

    1998-01-01

    This paper presents a numerical study of single-electron resonant tunnelling (RT) assisted by a few ionised donors in a laterally-confined resonant tunnelling diode (LCRTD). The 3D multi-mode S-matrix simulation is performed newly introducing the scattering potential of discrete impurities. With a few ionised donors being placed, the calculated energy-dependence of the total transmission rate shows new resonances which are donor-configuration dependent. Visualised electron prob...

  11. Characterisation of surface ionisation and adsorption of phenol and 4-nitrophenol on non-porous carbon blacks

    OpenAIRE

    Carrott, Peter; Carrott, Manuela; Vale, Tania; Valente Nabais, Joao; Mourao, Paulo

    2008-01-01

    The adsorption of phenol and 4-nitrophenol from aqueous solutions by carbon blacks was studied. Particular attention was paid to the characterisation of the surface chemistry and ionisation of the carbon blacks by use of a simple carbon surface ionisation model, as well as the use of a normalised form of the Freundlich equation for the analysis of the adsorption isotherms. The results indicated that the solutes interact directly with the graphene layers and that the adsorpti...

  12. On the effect of the ionising background on the Ly{\\alpha} forest autocorrelation function

    OpenAIRE

    Gontcho, Satya Gontcho A; Miralda-Escudé, Jordi; Busca, Nicolás G.

    2014-01-01

    An analytical framework is presented to understand the effects of a fluctuating intensity of the cosmic ionising background on the correlations of the Ly{\\alpha} forest transmission fraction measured in quasar spectra. In the absence of intensity fluctuations, the Ly{\\alpha} power spectrum should have the expected cold dark matter power spectrum with redshift distortions in the linear regime, with a bias factor b_{\\delta} and a redshift distortion parameter {\\beta} that depend on redshift but...

  13. Ionising radiation and risk of death from leukaemia and lymphoma in radiation-monitored workers (INWORKS)

    International Nuclear Information System (INIS)

    Since July 2015 the study ''ionising radiation and risk of death from leukaemia and lymphoma in radiation-monitored workers (INWORKS) - an international cohort study'' is available. INWORKS comprised data from 300.000 occupational exposed and dosimetric monitored persons from France, USA and UK. The contribution is a critical discussion of this study with respect to the conclusion of a strong evidence of positive associations between protracted low-dose irradiation exposure and leukemia.

  14. Ionisation and discharge in cloud-forming atmospheres of brown dwarfs and extrasolar planets

    Science.gov (United States)

    Helling, Ch; Rimmer, P. B.; Rodriguez-Barrera, I. M.; Wood, Kenneth; Robertson, G. B.; Stark, C. R.

    2016-07-01

    Brown dwarfs and giant gas extrasolar planets have cold atmospheres with rich chemical compositions from which mineral cloud particles form. Their properties, like particle sizes and material composition, vary with height, and the mineral cloud particles are charged due to triboelectric processes in such dynamic atmospheres. The dynamics of the atmospheric gas is driven by the irradiating host star and/or by the rotation of the objects that changes during its lifetime. Thermal gas ionisation in these ultra-cool but dense atmospheres allows electrostatic interactions and magnetic coupling of a substantial atmosphere volume. Combined with a strong magnetic field \\gg {{B}\\text{Earth}} , a chromosphere and aurorae might form as suggested by radio and x-ray observations of brown dwarfs. Non-equilibrium processes like cosmic ray ionisation and discharge processes in clouds will increase the local pool of free electrons in the gas. Cosmic rays and lighting discharges also alter the composition of the local atmospheric gas such that tracer molecules might be identified. Cosmic rays affect the atmosphere through air showers in a certain volume which was modelled with a 3D Monte Carlo radiative transfer code to be able to visualise their spacial extent. Given a certain degree of thermal ionisation of the atmospheric gas, we suggest that electron attachment to charge mineral cloud particles is too inefficient to cause an electrostatic disruption of the cloud particles. Cloud particles will therefore not be destroyed by Coulomb explosion for the local temperature in the collisional dominated brown dwarf and giant gas planet atmospheres. However, the cloud particles are destroyed electrostatically in regions with strong gas ionisation. The potential size of such cloud holes would, however, be too small and might occur too far inside the cloud to mimic the effect of, e.g. magnetic field induced star spots.

  15. The double ionisation of hydrogen by 5-30 keV protons

    International Nuclear Information System (INIS)

    The energy and angular distribution of pairs of fragment protons produced in H+-H2 collisions has been investigated in the energy range 5-30 keV. It is shown that the energy distribution is a simple transformation of the ground-state wavefunction of H2 and an experimental determination of the ground-state probability density distribution is presented. Total and differential double ionisation cross sections are found to be in accord with earlier measurements. (author)

  16. Ionising radiation and risk of death from leukaemia and lymphoma in radiation-monitored workers (INWORKS)

    Energy Technology Data Exchange (ETDEWEB)

    Lorenz, Bernd

    2015-07-01

    Since July 2015 the study ''ionising radiation and risk of death from leukaemia and lymphoma in radiation-monitored workers (INWORKS) - an international cohort study'' is available. INWORKS comprised data from 300.000 occupational exposed and dosimetric monitored persons from France, USA and UK. The contribution is a critical discussion of this study with respect to the conclusion of a strong evidence of positive associations between protracted low-dose irradiation exposure and leukemia.

  17. Determination of the ionisation potential of certain hydrocarbons in the liquid phase

    International Nuclear Information System (INIS)

    The first results obtained are presented on the determination of the ionisation potential of four alkanes (n-hexane, n-pentane, cyclopentane and trimethyl-2,2,4 pentane) in the liquid phase. In the gaseous phase, the ionisation potential values of these hydrocarbons are respectively 10.18 eV for n-hexane, 10.35 eV for n-pentane, 10.53 eV for cyclopentane and 9.86 eV for trimethyl-2,2,4 pentane. Consequently rare gas resonance lamps (krypton and Xenon) were made, sealed and excited by an ultra-high frequency wave, which emit photons in the energy field concerned, i.e. from 8.5 eV to 11eV. The energy of the photons emitted by these lamps is respectively 8.44 eV (100%) and 9.57 eV (2%) for xenon and 10.03 eV (100%) and 10.64 eV (5%) for krypton. From the extent of the induced ionisation currents and particularly the value of the ratio of the currents induced by the photons of the krypton and xenon lamps, a minimum value of the ionisation potential drop can be deduced compared with the gas phase of 0.61 eV for n-hexane, 0.78 eV for n-pentane, 0.96 eV for cyclopentane and a maximum value of 1.42 eV for trimethyl-2,2,4 pentane

  18. Computer modeling and experimental work on the astrobiological implications of the martian subsurface ionising radiation environment

    OpenAIRE

    Dartnell, L. R.

    2008-01-01

    Any microbial life extant in the top meters of the martian subsurface is likely to be held dormant for long periods of time by the current permafrost conditions. In this potential habitable zone, a major environmental hazard is the ionising radiation field generated by the flux of exogenous energetic particles: solar energetic protons and galactic cosmic rays. The research reported here constitutes the first multidisciplinary approach to assessing the astrobiological impact of ...

  19. Exposure of the French paediatric population to ionising radiation from diagnostic medical procedures in 2010

    Energy Technology Data Exchange (ETDEWEB)

    Etard, Cecile; Aubert, Bernard [Institut de Radioprotection et de Surete Nucleaire, Medical Expertise Unit, Fontenay-aux-Roses (France); Mezzarobba, Myriam [Institut de Radioprotection et de Surete Nucleaire, Laboratory of Epidemiology, Fontenay-aux-Roses (France); Bernier, Marie-Odile [Institut de Radioprotection et de Surete Nucleaire, Laboratory of Epidemiology, Fontenay-aux-Roses (France); Institut de Radioprotection et de Surete Nucleaire, IRSN/PRP-HOM/SRBE/LEPID, Laboratoire d' Epidemiologie, Fontenay-aux-Roses (France)

    2014-12-15

    Medical examination is the main source of artificial radiation exposure. Because children present an increased sensitivity to ionising radiation, radiology practices at a national level in paediatrics should be monitored. This study describes the ionising radiation exposure from diagnostic medical examinations of the French paediatric population in 2010. Data on frequency of examinations were provided by the French National Health Insurance through a representative sample including 107,627 children ages 0-15 years. Effective doses for each type of procedure were obtained from the published French literature. Median and mean effective doses were calculated for the studied population. About a third of the children were exposed to at least one examination using ionising radiation in 2010. Conventional radiology, dental exams, CT scans and nuclear medicine and interventional radiology represent respectively 55.3%, 42.3%, 2.1% and 0.3% of the procedures. Children 10-15 years old and babies from birth to 1 year are the most exposed populations, with respectively 1,098 and 734 examinations per 1,000 children per year. Before 1 year of age, chest and pelvis radiographs are the most common imaging tests, 54% and 32%, respectively. Only 1% of the studied population is exposed to CT scan, with 62% of these children exposed to a head-and-neck procedure. The annual median and mean effective doses were respectively 0.03 mSv and 0.7 mSv for the exposed children. This study gives updated reference data on French paediatric exposure to medical ionising radiation that can be used for public health or epidemiological purposes. Paediatric diagnostic use appears much lower than that of the whole French population as estimated in a previous study. (orig.)

  20. Helium-Nanotröpfchen : Pump-Probe-Ionisation von Alkalidotierungen und Spinechostreuung an undotierten Tropfen

    OpenAIRE

    Droppelmann, Georg

    2005-01-01

    In dieser Arbeit werden verschiedenste experimentelle Studien im Zusammenhang mit Helium-Nanotröpfchen präsentiert. Im einzelnen sind dies: Untersuchungen zur Bildungsdynamik der Exziplexe RbHe und KHe auf Nanotröpfchen aus Helium-4 bzw. Helium-3 sowie zu den dabei auftretenden Quanteninterferenzen; Untersuchungen zur Oberflächendynamik der Nanotröpfchen anhand der Pump-Probe-Ionisation von Cäsiumatomen; Untersuchungen zur Stabilität gemischter Hochspin-Alkalicluster; Untersuchung...

  1. The effect of the 1985 Ionising Radiations Regulations on a service inspection company

    International Nuclear Information System (INIS)

    The paper concerns the significant changes and requirements resulting from the 1985 Ionising Radiations Regulations, and examines their effect on the administration and operations of a service inspection company engaging in Industrial Radiography. The major innovations introduced by the 1985 Regulations are discussed under three topic headings: 1) local rules and radiation protection personnel, 2) controlled and supervised areas, and 3) hazard assessments and contingency plans. (U.K.)

  2. Ionising radiation-induced DNA damage response in marine mussels, Mytilus edulis

    OpenAIRE

    Alamri, Ohoud

    2012-01-01

    The effects of ionising radiation (IR) present in aquatic environments have been observed principally in vertebrate species but the potential biological impacts for aquatic invertebrate species are less clear. It is important to determine the influence of IR as a pollutant causing DNA damage in invertebrates at the molecular level since this may serve as an early warning of future population level repercussions. In this study, the biological effects of the IR as an environemnt...

  3. The philosophy and assumptions underlying exposure limits for ionising radiation, inorganic lead, asbestos and noise

    International Nuclear Information System (INIS)

    Full text: A review of the literature relating to exposure to, and exposure limits for, ionising radiation, inorganic lead, asbestos and noise was undertaken. The four hazards were chosen because they were insidious and ubiquitous, were potential hazards in both occupational and environmental settings and had early and late effects depending on dose and dose rate. For all four hazards, the effect of the hazard was enhanced by other exposures such as smoking or organic solvents. In the cases of inorganic lead and noise, there were documented health effects which affected a significant percentage of the exposed populations at or below the [effective] exposure limits. This was not the case for ionising radiation and asbestos. None of the exposure limits considered exposure to multiple mutagens/carcinogens in the calculation of risk. Ionising radiation was the only one of the hazards to have a model of all likely exposures, occupational, environmental and medical, as the basis for the exposure limits. The other three considered occupational exposure in isolation from environmental exposure. Inorganic lead and noise had economic considerations underlying the exposure limits and the exposure limits for asbestos were based on the current limit of detection. All four hazards had many variables associated with exposure, including idiosyncratic factors, that made modelling the risk very complex. The scientific idea of a time weighted average based on an eight hour day, and forty hour week on which the exposure limits for lead, asbestos and noise were based was underpinned by neither empirical evidence or scientific hypothesis. The methodology of the ACGIH in the setting of limits later brought into law, may have been unduly influenced by the industries most closely affected by those limits. Measuring exposure over part of an eight hour day and extrapolating to model exposure over the longer term is not the most effective way to model exposure. The statistical techniques used

  4. International Atomic Energy Agency Regional Workshop on Commercialisation of ionising energy treatment of food: proceedings

    International Nuclear Information System (INIS)

    The global need to ensure adequate food supplies places a demand on new technologies and techniques to improve yields and preservation of food by eliminating or reducing bacterial degradation and infestation of raw or processed foods. The use of ionising radiation in food processing also has potential to alleviate certain food-borne diseases which cause serious threats to the health of people in many countries

  5. Time-dependent hydrogen ionisation in the solar chromosphere. I: Methods and first results

    CERN Document Server

    Wedemeyer-Boehm, J L S

    2006-01-01

    An approximate method for solving the rate equations for the hydrogen populations was extended and implemented in the three-dimensional radiation (magneto-)hydrodynamics code CO5BOLD. The method is based on a model atom with six energy levels and fixed radiative rates. It has been tested extensively in one-dimensional simulations. The extended method has been used to create a three-dimensional model that extends from the upper convection zone to the chromosphere. The ionisation degree of hydrogen in our time-dependent simulation is comparable to the corresponding equilibrium value up to 500 km above optical depth unity. Above this height, the non-equilibrium ionisation degree is fairly constant over time and space, and tends to be at a value set by hot propagating shock waves. The hydrogen level populations and electron density are much more constant than the corresponding values for statistical equilibrium, too. In contrast, the equilibrium ionisation degree varies by more than 20 orders of magnitude between...

  6. Health protection of persons occupationally exposed to ionising radiation in Croatia

    International Nuclear Information System (INIS)

    The aim of this study was to investigate the health condition of workers occupationally exposed to ionising radiation. The results for 1406 workers exposed to ionising radiations, who were regularly examined in 2004, were analysed using Statistica 5.0. The analysis included workers' case histories, frequency of illnesses and causes of temporary or permanent work disability. Of 1406 workers, 16 (1.13%) were found permanently disabled; in 11 the cause of disability was lens opacity, in 2 persistent trombocitophenia, and in 2 malignant tumour. Twenty-four workers were temporarily disabled, of whom 5 due to pregnancy. Thrombocytopenia was found in 12 men and only one woman. Anaemia was found in 4 women; dicentric chromosomes were the cause of temporary disability in one person, and tuberculosis in one person. Medical examinations of Croatian workers confirm low occupational exposure to ionising radiation. With this type of radiation, the established lens impairments could not be characterised as occupational. The two malignant tumours however were recognised as occupational diseases.(author)

  7. Ambient ionisation mass spectrometry for the characterisation of polymers and polymer additives: a review.

    Science.gov (United States)

    Paine, Martin R L; Barker, Philip J; Blanksby, Stephen J

    2014-01-15

    The purpose of this review is to showcase the present capabilities of ambient sampling and ionisation technologies for the analysis of polymers and polymer additives by mass spectrometry (MS) while simultaneously highlighting their advantages and limitations in a critical fashion. To qualify as an ambient ionisation technique, the method must be able to probe the surface of solid or liquid samples while operating in an open environment, allowing a variety of sample sizes, shapes, and substrate materials to be analysed. The main sections of this review will be guided by the underlying principle governing the desorption/extraction step of the analysis; liquid extraction, laser ablation, or thermal desorption, and the major component investigated, either the polymer itself or exogenous compounds (additives and contaminants) present within or on the polymer substrate. The review will conclude by summarising some of the challenges these technologies still face and possible directions that would further enhance the utility of ambient ionisation mass spectrometry as a tool for polymer analysis.

  8. New low-frequency electromagnetic modes associated with neutral dynamics in partially ionised plasma

    Directory of Open Access Journals (Sweden)

    A. A. Shaikh

    2013-05-01

    Full Text Available We have investigated the low frequency electromagnetic (EM modes in inhomogeneous, magnetised partially ionised plasma by incorporating neutral dynamics. We have derived a general EM dispersion relation by using a two-fluids magnetohydrodynamics (MHD model. Our analysis shows that the neutral dynamics is playing an extremely important role in the physics of magnetised partially ionised plasma by giving rise to new kind of EM modes. We found (1 the new instability is linked with compressibility of neutral particles, the collision between neutral and charged species and the relative streaming in hot/cold, inhomogeneous, magnetised partially ionised plasma, (2 and that neutral dynamics is responsible for the modified (complex inertial effect on magnetic field lines. Its consequences on the propagation characteristics of Alfvén wave and cyclotron frequency are discussed. Furthermore, a new mode similar to the Langmuir mode is reported. Finally, we discuss our results, for limiting cases, that may be appropriate for applications to space plasma environments including probable mechanism of escaping H+ and O− from the Martian atmosphere.

  9. Field calibration studies for ionisation chambers in mixed high-energy radiation fields.

    Science.gov (United States)

    Theis, C; Forkel-Wirth, D; Fuerstner, M; Mayer, S; Otto, Th; Roesler, S; Vincke, H

    2007-01-01

    The monitoring of ambient doses at work places around high-energy accelerators is a challenging task due the complexity of the mixed stray radiation fields encountered. At CERN, mainly Centronics IG5 high-pressure ionisation chambers are used to monitor radiation exposure in mixed fields. The monitors are calibrated in the operational quantity ambient dose equivalent H*(10) using standard, source-generated photon- and neutron fields. However, the relationship between ionisation chamber reading and ambient dose equivalent in a mixed high-energy radiation field can only be assessed if the spectral response to every component and the field composition is known. Therefore, comprehensive studies were performed at the CERN-EU high-energy reference field facility where the spectral fluence for each particle type has been assessed with Monte Carlo simulations. Moreover, studies have been performed in an accessible controlled radiation area in the vicinity of a beam loss point of CERN's proton synchrotron. The comparison of measurements and calculations has shown reasonable agreement for most exposure conditions. The results indicate that conventionally calibrated ionisation chambers can give satisfactory response in terms of ambient dose equivalent in stray radiation fields at high-energy accelerators in many cases. These studies are one step towards establishing a method of 'field calibration' of radiation protection instruments in which Monte Carlo simulations will be used to establish a correct correlation between the response of specific detectors to a given high-energy radiation field.

  10. La diaspora, instrument de la politique de puissance et de rayonnement de l’Inde à l’île Maurice et dans le monde

    Directory of Open Access Journals (Sweden)

    Anouck Carsignol-Singh

    2009-11-01

    Full Text Available Les Persons of Indian Origin (PIO ont depuis le début du XXe siècle servi de levier à l’intelligentsia indienne pour rehausser l’image du pays et contribuer à son rayonnement culturel sur la scène internationale, en tant qu’ambassadeurs culturels de l’Inde dans leur pays de résidence. Aujourd’hui, les nouveaux liens établis entre New Delhi et les Non Resident Indians (NRI dépassent largement le cadre de la diplomatie culturelle, et leur mobilisation économique ou politique en faveur du traité nucléaire contribuent à l’affirmation de la puissance de l’Inde. Une analyse de la mobilisation des Indo-Mauriciens permet de mettre en lumière le double rôle du facteur diasporique dans l’émergence de l’Inde comme grande puissance régionale et internationale, en tant qu’instrument à la fois du Soft Power et de la Realpolitik de New Delhi.People of Indian Origin (PIOs have, since the beginning of the XXth century, been used by the Indian intelligentsia to promote the image of the sub-continent and diffuse India’s cultural values on the international stage, as cultural ambassadors of India in their host countries. Today, the new partnership between New Delhi and the Non Resident Indians (NRIs go beyond India’s cultural diplomacy, and the support of the Diaspora in favour of the nuclear deal plays a strategic part in the affirmation of India as an emerging power. An analysis of the mobilisation of Indo-Mauritians in line with the interests and values of India illustrates the double role of the diasporic factor in the emergence of India as a regional and global power, as a tool of New Delhi’s soft power and Realpolitik.

  11. Les représentations sociales du travail dans des parcours de retour aux études aux niveaux collégial et universitaire

    OpenAIRE

    Claude Julie Bourque; Pierre Doray

    2009-01-01

    Cet article porte sur le volet éducatif de la production et de la reproduction de la main-d’œuvre hautement qualifiée par l’examen des processus en jeu au moment des retours aux études dans des programmes de formation technique et de génie. Nous nous intéressons en particulier à une situation emblématique des référentiels politiques récents en matière d’éducation, soit les retours aux études. Nous cherchons à mieux comprendre comment le retour aux études se réalise, comment les représentation...

  12. Introduction aux études sur le genre. - 2e éd. revue et augm.

    NARCIS (Netherlands)

    L. Bereni; S. Chauvin; A. Jaunait; A. Revillard

    2012-01-01

    Pourquoi offre-t-on des poupées aux filles et des voitures aux garçons ? Pourquoi les femmes gagnent-elles moins que les hommes ? Comment expliquer qu’elles effectuent les deux tiers du travail domestique ? Pourquoi est-ce si mal vu pour un homme d’être efféminé ? Le pouvoir est-il intrinsèquement m

  13. Aux limites de la physique les paradoxes quantiques

    CERN Document Server

    Rothen, François

    2012-01-01

    Dans l’esprit des pères fondateurs de la science moderne, les phénomènes matériels se déroulent selon un schéma unique. La cause précède nécessairement l’effet, et la connaissance de l’effet permet de remonter à la cause. Sur la scène de la nature, le hasard n’occupe qu’une place congrue. On ne fait appel à lui que pour pallier notre ignorance. Dans les années 1920, la révolution quantique bouleverse ce cadre rigide. Elle accorde une place de choix au hasard, si malmené jusqu’alors, puis elle met en scène une constellation de phénomènes inexplicables aux yeux de la science dite classique. Après une courte introduction historique, l’auteur met ses lecteurs au contact de certains de ces phénomènes si contraires à l’intuition. Refusant l’aide du langage mathématique, il les convie à pénétrer dans un monde quantique qui déconcerte le novice avant de l’éblouir par sa nouveauté et sa cohérence. Un accent particulier est mis sur une application nouvelle de la physiqu...

  14. Caractérisation et modélisation des émissions rayonnées par le câblage des systèmes électroniques embarqués

    OpenAIRE

    Yahyaoui, Wissem,

    2011-01-01

    La cohabitaion, dans une même enceinte, des systèmes électroniques de puissance et decommande est un risque majeur pour le bon fonctionnement des systèmes électroniquesembarqués (Automobile, Aéronautique et Spatial). La maitrise de la CEM de ces systèmes estun défit surtout avec la difficulté de rendre compte des phénomènes EM.Ce mémoire décrit la modélisation des émissions conduites et des émissions EM rayonnéespar le câblage des systèmes électroniques embarqués. On explique d’abord le choix...

  15. Connecting the dots: a correlation between ionising radiation and cloud mass-loss rate traced by optical integral field spectroscopy

    CERN Document Server

    McLeod, A F; Dale, J E; Ginsburg, A; Klaassen, P D; Mottram, J C; Preibisch, T; Ramsay, S; Reiter, M; Testi, L

    2016-01-01

    We present an analysis of the effect of feedback from O- and B-type stars with data from the integral field spectrograph MUSE mounted on the Very Large Telescope of pillar-like structures in the Carina Nebular Complex, one of the most massive star-forming regions in the Galaxy. For the observed pillars, we compute gas electron densities and temperatures maps, produce integrated line and velocity maps of the ionised gas, study the ionisation fronts at the pillar tips, analyse the properties of the single regions, and detect two ionised jets originating from two distinct pillar tips. For each pillar tip we determine the incident ionising photon flux $Q_\\mathrm{0,pil}$ originating from the nearby massive O- and B-type stars and compute the mass-loss rate $\\dot{M}$ of the pillar tips due to photo-evaporation caused by the incident ionising radiation. We combine the results of the Carina data set with archival MUSE data of a pillar in NGC 3603 and with previously published MUSE data of the Pillars of Creation in M...

  16. Characterisation of the muon beams for the Muon Ionisation Cooling Experiment

    OpenAIRE

    The MICE Collaboration; Adams, D.; Adey, D.; Alekou, A.; Apollonio, M; Asfandiyarov, R.; Back, J.; Barber, G.; Barclay, P.; de Bari, A.; Bayes, R.; Bayliss, V.; Bertoni, R.; Blackmore, V. J.; Blondel, A.

    2013-01-01

    A novel single-particle technique to measure emittance has been developed and used to characterise seventeen different muon beams for the Muon Ionisation Cooling Experiment (MICE). The muon beams, whose mean momenta vary from 171 to 281 MeV/c, have emittances of approximately 1.5--2.3 \\pi mm-rad horizontally and 0.6--1.0 \\pi mm-rad vertically, a horizontal dispersion of 90--190 mm and momentum spreads of about 25 MeV/c. There is reasonable agreement between the measured para...

  17. The ionised, radical and molecular Milky Way: spectroscopic surveys with the SKA

    CERN Document Server

    Thompson, Mark; Dickinson, Clive; Mottram, Joseph C; Klaassen, Pamela; Ginsburg, Adam; Longmore, Steve; Remijan, Anthony; Menten, Karl

    2014-01-01

    The bandwith, sensitivity and sheer survey speed of the SKA offers unique potential for deep spectroscopic surveys of the Milky Way. Within the frequency bands available to the SKA lie many transitions that trace the ionised, radical and molecular components of the interstellar medium and which will revolutionise our understanding of many physical processes. In this chapter we describe the impact on our understanding of the Milky Way that can be achieved by spectroscopic SKA surveys, including "out of the box" early science with radio recombination lines, Phase 1 surveys of the molecular ISM using anomalous formaldehyde absorption, and full SKA surveys of ammonia inversion lines.

  18. Extrapolation ionisation chamber measurements on beta-emitting sources produced for the CEGB collaborative radiobiology programme

    International Nuclear Information System (INIS)

    This report describes the structure and application of an extrapolation ionisation chamber used for measuring dose-rates from plane and point beta-emitting sources. These measurements form the basis of the dosimetry for a collaborative radiobiological study of skin to study both stochastic and non-stochastic effects. A small sample from the wide range of measurements undertaken in the programme has been selected to illustrate the procedures involved. The extrapolation chamber is currently being automated and it is intended that this report should provide a source reference to the basis of the measurements made between 1977-86. (author)

  19. Calculation of the electric field inside electret ionisation chambers - Influence on the response function

    International Nuclear Information System (INIS)

    The use of electret ion chambers for gamma dose and radon exposure measurement was increasing rapidly in the last years. In contrast to conventional ion chambers, the electric field in these detectors is not constant during the exposure time. Both field-strength and direction are changing due to inhomogeneous decrease of the electret surface charges. Data of numerical field calculations inside cylindrical electret Ionisation chambers are given. The change of the field-strength distribution with respect to electret discharge is described. The influence on the response function is discussed and experimentally verified. (author)

  20. Characterisation of the muon beams for the Muon Ionisation Cooling Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Adams, D.; et al.,

    2013-10-01

    A novel single-particle technique to measure emittance has been developed and used to characterise seventeen different muon beams for the Muon Ionisation Cooling Experiment (MICE). The muon beams, whose mean momenta vary from 171 to 281 MeV/c, have emittances of approximately 1.5--2.3 \\pi mm-rad horizontally and 0.6--1.0 \\pi mm-rad vertically, a horizontal dispersion of 90--190 mm and momentum spreads of about 25 MeV/c. There is reasonable agreement between the measured parameters of the beams and the results of simulations. The beams are found to meet the requirements of MICE.

  1. First on-line results from the CRIS (Collinear Resonant Ionisation Spectroscopy) beam line at ISOLDE

    International Nuclear Information System (INIS)

    The CRIS (Collinear Resonant Ionisation Spectroscopy) experiment at the on-line isotope separator facility, ISOLDE, CERN, has been constructed for high-sensitivity laser spectroscopy measurements on radioactive isotopes. The technique determines the magnetic dipole and electric quadrupole moments, nuclear spin and changes in mean-square charge radii of exotic nuclei via measurement of their hyperfine structures and isotope shifts. In November 2011 the first on-line run was performed using the CRIS beam line, when the hyperfine structure of 207Fr was successfully measured. This paper will describe the technique and experimental setup of CRIS and present the results from the first on-line experiment.

  2. The low dose gamma ionising radiation impact upon cooperativity of androgen-specific proteins

    International Nuclear Information System (INIS)

    The paper deals with effects of the ionising radiation (γ-IR, 0.5 Gy) upon serum testosterone (T), characteristics of testosterone-binding globulin (TeBG) and androgen receptor (AR) in parallel with observation of androgen (A) responsive enzyme activity – hexokinase (HK). The interdependence or relationships of T-levels with parameters of the proteins that provide androgenic regulation are consequently analyzed in post-IR dynamics. The IR-stress adjustment data reveal expediency of TeBG- and AR-cooperativity measurements for more precise assessments of endocrine A-control at appropriate emergencies

  3. Characterisation of the Muon Beams for the Muon Ionisation Cooling Experiment

    CERN Document Server

    Adams, D; Alekou, A; Apollonio, M; Asfandiyarov, R; Back, J; Barber, G; Barclay, P; de Bari, A; Bayes, R; Baynham, D E; Bertoni, R; Blackmore, V J; Blondel, A; Blot, S; Bogomilov, M; Bonesini, M; Booth, C N; Bowring, D; Boyd, S; Bradshaw, T W; Bravar, U; Bross, A D; Capponi, M; Carlisle, T; Cecchet, G; Charnley, G; Cobb, J H; Colling, D; Collomb, N; Coney, L; Cooke, P; Courthold, M; Cremaldi, L M; DeMello, A; Dick, A; Dobbs, A; Dornan, P; Fayer, S; Filthaut, F; Fish, A; Fitzpatrick, T; Fletcher, R; Forrest, D; Francis, V; Freemire, B; Fry, L; Gallagher, A; Gamet, R; Gourlay, S; Grant, A; Graulich, J S; Griffiths, S; Hanlet, P; Hansen, O M; Hanson, G G; Harrison, P; Hart, T L; Hartnett, T; Hayler, T; Heidt, C; Hills, M; Hodgson, P; Hunt, C; Iaciofano, A; Ishimoto, S; Kafka, G; Kaplan, D M; Karadzhov, Y; Kim, Y K; Kolev, D; Kuno, Y; Kyberd, P; Lau, W; Leaver, J; Leonova, M; Li, D; Lintern, A; Littlefield, M; Long, K; Lucchini, G; Luo, T; Macwaters, C; Martlew, B; Martyniak, J; Middleton, S; Moretti, A; Moss, A; Muir, A; Mullacrane, I; Nebrensky, J J; Neuffer, D; Nichols, A; Nicholson, R; Nugent, J C; Onel, Y; Orestano, D; Overton, E; Owens, P; Palladino, V; Palmer, R B; Pasternak, J; Pastore, F; Pidcott, C; Popovic, M; Preece, R; Prestemon, S; Rajaram, D; Ramberger, S; Rayner, M A; Ricciardi, S; Richards, A; Roberts, T J; Robinson, M; Rogers, C; Ronald, K; Rubinov, P; Rucinski, R; Rusinov, I; Sakamoto, H; Sanders, D A; Santos, E; Savidge, T; Smith, P J; Snopok, P; Soler, F J P; Summers, D J; Takahashi, M; Tarrant, J; Taylor, I; Tortora, L; Torun, Y; Tsenov, R; Tunnell, C D; Vankova, G; Verguilov, V; Virostek, S; Vretenar, M; Walaron, K; Watson, S; White, C; Whyte, C G; Wilson, A; Wisting, H; Zisman, M

    2013-01-01

    A novel single-particle technique to measure emittance has been developed and used to characterise seventeen different muon beams for the Muon Ionisation Cooling Experiment (MICE). The muon beams, whose mean momenta vary from 171 to 281 MeV/c, have emittances of approximately 1.5--2.3 \\pi mm-rad horizontally and 0.6--1.0 \\pi mm-rad vertically, a horizontal dispersion of 90--190 mm and momentum spreads of about 25 MeV/c. There is reasonable agreement between the measured parameters of the beams and the results of simulations. The beams are found to meet the requirements of MICE.

  4. Characterisation of the muon beams for the Muon Ionisation Cooling Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Adams, D.; Barclay, P.; Bayliss, V.; Bradshaw, T.W.; Courthold, M.; Francis, V.; Fry, L.; Hayler, T.; Hills, M.; Lintern, A.; Macwaters, C.; Nichols, A.; Preece, R.; Ricciardi, S.; Rogers, C.; Stanley, T.; Tarrant, J.; Watson, S.; Wilson, A. [Harwell Oxford, STFC Rutherford Appleton Laboratory, Didcot (United Kingdom); Adey, D.; Back, J.; Boyd, S.; Harrison, P.; Pidcott, C.; Taylor, I. [University of Warwick, Department of Physics, Coventry (United Kingdom); Alekou, A.; Apollonio, M.; Barber, G.; Colling, D.; Dobbs, A.; Dornan, P.; Fayer, S.; Fish, A.; Hunt, C.; Leaver, J.; Long, K.; Martyniak, J.; Middleton, S.; Pasternak, J.; Richards, A.; Santos, E.; Savidge, T.; Takahashi, M. [Imperial College London, Department of Physics, Blackett Laboratory, London (United Kingdom); Asfandiyarov, R.; Blondel, A.; Graulich, J.S.; Karadzhov, Y.; Verguilov, V.; Wisting, H. [Universite de Geneve, DPNC, Section de Physique, Geneva (Switzerland); De Bari, A.; Cecchet, G. [Sezione INFN Pavia (Italy); Dipartimento di Fisica Nucleare e Teorica, Pavia (Italy); Bayes, R.; Forrest, D.; Nugent, J.C.; Soler, F.J.P.; Walaron, K. [The University of Glasgow, School of Physics and Astronomy, Glasgow (United Kingdom); Bertoni, R.; Bonesini, M.; Lucchini, G. [Sezione INFN Milano Bicocca (Italy); Dipartimento di Fisica G. Occhialini, Milano (Italy); Blackmore, V.J.; Carlisle, T.; Cobb, J.H.; Lau, W.; Rayner, M.A.; Tunnell, C.D. [University of Oxford, Department of Physics, Oxford (United Kingdom); Blot, S.; Kim, Y.K. [University of Chicago, Enrico Fermi Institute, Chicago, IL (United States); Bogomilov, M.; Kolev, D.; Rusinov, I.; Tsenov, R.; Vankova, G. [St. Kliment Ohridski University of Sofia, Department of Atomic Physics, Sofia (Bulgaria); Booth, C.N.; Hodgson, P.; Nicholson, R.; Overton, E.; Robinson, M.; Smith, P.J. [University of Sheffield, Department of Physics and Astronomy, Sheffield (United Kingdom); Bowring, D.; DeMello, A.; Gourlay, S.; Li, D.; Prestemon, S.; Virostek, S.P.; Zisman, M.S. [Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Bravar, U. [University of New Hampshire, Durham, NH (United States); Bross, A.D.; Fitzpatrick, T.; Leonova, M.; Moretti, A.; Neuffer, D.; Popovic, M.; Rubinov, P.; Rucinski, R. [Fermilab, Batavia, IL (United States); Capponi, M.; Iaciofano, A.; Orestano, D.; Pastore, F.; Tortora, L. [Sezione INFN Roma Tre e Dipartimento di Fisica, Roma (Italy); Charnley, G.; Collomb, N.; Gallagher, A.; Grant, A.; Griffiths, S.; Hartnett, T.; Martlew, B.; Moss, A.; Muir, A.; Mullacrane, I.; Owens, P.; White, C. [STFC Daresbury Laboratory, Cheshire (United Kingdom); Coney, L.; Fletcher, R.; Hanson, G.G.; Heidt, C. [University of California, Riverside, CA (United States); Cooke, P.; Gamet, R. [University of Liverpool, Department of Physics, Liverpool (United Kingdom); Cremaldi, L.M.; Hart, T.L.; Luo, T.; Sanders, D.A.; Summers, D.J. [University of Mississippi, Oxford, MS (United States); Dick, A.J.; Ronald, K.; Whyte, C.G. [University of Strathclyde, Department of Physics, Glasgow (United Kingdom); Filthaut, F. [NIKHEF, Amsterdam (Netherlands); Freemire, B.; Hanlet, P.; Kafka, G.; Kaplan, D.M.; Rajaram, D.; Snopok, P.; Torun, Y. [Illinois Institute of Technology, Chicago, IL (United States); Hansen, O.M.; Ramberger, S.; Vretenar, M. [CERN, Geneva (Switzerland); Ishimoto, S. [Institute of Particle and Nuclear Studies, High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki (Japan); Kuno, Y.; Sakamoto, H. [Osaka University, Graduate School of Science, Department of Physics, Toyonaka, Osaka (Japan); Kyberd, P.; Littlefield, M.; Nebrensky, J.J. [Brunel University, Uxbridge (United Kingdom); Onel, Y. [University of Iowa, Department of Physics and Astronomy, Iowa City, IA (United States); Palladino, V. [Universita Federico II, Sezione INFN Napoli (Italy); Dipartimento di Fisica, Napoli (Italy); Palmer, R.B. [Brookhaven National Laboratory, Upton, NY (US); Roberts, T.J. [Muons, Inc., Batavia, IL (US); Collaboration: The MICE Collaboration

    2013-10-15

    A novel single-particle technique to measure emittance has been developed and used to characterise seventeen different muon beams for the Muon Ionisation Cooling Experiment (MICE). The muon beams, whose mean momenta vary from 171 to 281 MeV/c, have emittances of approximately 1.2-2.3 {pi} mm-rad horizontally and 0.6-1.0 {pi} mm-rad vertically, a horizontal dispersion of 90-190 mm and momentum spreads of about 25 MeV/c. There is reasonable agreement between the measured parameters of the beams and the results of simulations. The beams are found to meet the requirements of MICE. (orig.)

  5. Relations between age at occupational exposure to ionising radiation and cancer risk.

    OpenAIRE

    Stewart, A. M.; Kneale, G. W.

    1996-01-01

    OBJECTIVES: To discover how the age when a given dose of ionising radiation is received (exposure age) affects the subsequent cancer risk, and whether the types of cancer caused by repeated exposure to small doses during adult life differ from naturally occurring cancers at that age. METHOD: A nested case-control design with all possible controls in a cohort of nuclear workers, and a Mantel-Haenszel test (requiring only one degree of freedom) to discover whether there was any level of exposur...

  6. A digital interface for preset time or voltage measurements using an ionising radiation dosemeter

    International Nuclear Information System (INIS)

    A digital interface circuit has been built to terminate charge collection measurements made with an ionising radiation dosemeter. A compact portable measurement system has been assembled, comprising a digital voltmeter, a period timer and the digital interface module. Digital signals from both the voltmeter and the timer are compared with separate preset limits, and the dosemeter measurement is terminated when one of these limits is reached. The operation of the dosemeter is outlined, and the interface circuit is described in detail. Modifications to the voltmeter and timer are described, and comprehensive users' instructions are given

  7. Estimation of useful yield in surface analysis using single photon ionisation

    Science.gov (United States)

    King, B. V.; Pellin, M. J.; Moore, J. F.; Veryovkin, I. V.; Savina, M. R.; Tripa, C. E.

    2003-01-01

    Secondary ion mass spectrometry (SIMS), laser sputter neutral mass spectrometry (SNMS) and laser desorption photoionisation (LDPI) have been used to investigate the desorption of molecules from self-assembled monolayers of phenylsulphides. LDPI, using an F 2 excimer laser to single photon ionise gave the lowest fragmentation. A useful yield greater than 0.5% was found for analysis of diphenyldisulphide self-assembled monolayers. It is shown that using a free electron laser to postionise will lead, in the future, to analysis of many atoms and molecules with useful yields approaching 30%.

  8. Calculated ionisation potentials to determine the oxidation of vanillin precursors by lignin peroxidase.

    OpenAIRE

    R Ten Have; I.M.C.M. Rietjens; Hartmans, S; Swarts, H.J.; Field, J. A.

    1998-01-01

    In view of the biocatalytic production of vanillin, this research focused on the lignin peroxidase (LiP) catalysed oxidation of naturally occurring phenolic derivatives: O-methyl ethers, O-acetyl esters, and O-glucosyl ethers. The ionisation potential (IP) of a series of model compounds was calculated and compared to their experimental conversion by LiP, defining a relative IP threshold of approximately 9.0 eV. Based on this threshold value only the O-acetyl esters and glucosides of isoeugeno...

  9. Design and performance of an ionisation chamber for the measurement of low alpha-activities

    CERN Document Server

    Hartmann, Andreas; Krüger, Felix; Sobiella, Manfred; Wilsenach, Heinrich; Zuber, Kai

    2015-01-01

    A new ionisation chamber for alpha-spectroscopy has been built from radio-pure materials for the purpose of investigating long lived alpha-decays. The measurement makes use of pulse shape analysis to discriminate between signal and background events. The design and performance of the chamber is described in this paper. A background rate of ($10.9 \\pm 0.6$) counts per day in the energy region of 1 MeV to 9 MeV was achieved with a run period of 30.8 days. The background is dominantly produced by radon daughters.

  10. The potential use of diamond coated tungsten tips as a field ionisation source

    Energy Technology Data Exchange (ETDEWEB)

    Brown, A.; Prawer, S.; Legge, G.J.F.; Kostidis, L.I. [Melbourne Univ., Parkville, VIC (Australia). School of Physics

    1996-12-31

    Tungsten tips are convenient for use in a high brightness gaseous phase field ionisation source. However, the lifetime of these tips is not adequate for practical use. The authors are investigating whether coating tungsten tips with diamond using Chemical Vapor Deposition (CVD) will improve the practicality of using these tips by an improvement in longevity of the source and/or an improvement in brightness due to the effects of the property of negative electron affinity which has been observed on CVD diamond. 1 ref.

  11. Combined effects of ionising gamma radiation and some chemical substances on the Allium sativum growth

    International Nuclear Information System (INIS)

    Co 60 - gamma ionising radiations act in different doses and flows on Allium sativum. They accelerate the germination of bulblets with a couple of days by comparison with the sample. The 10 Gy dose stimulates the plants growth. The 30 Gy dose or 'shock dose' related to the radiation flow and with chemicals used in the treatment, produces strong decays or raises of biological parameter values. The growth region which is implied in growing regulators synthesis is perturbed. The calculation of nuclear and cytoplasmic volumes of nucleus-cytoplasm ratio confirms the perturbation at this level. (Author)

  12. Investigating ionisation cluster size distribution due to sub-1 keV electrons in view of Heisenberg's Uncertainty

    Science.gov (United States)

    Li, B.; Palmans, H.; Hao, L.; Nisbet, A.

    2015-09-01

    As the wavelengths of low energy electrons become comparable with the length scale of the mean ionisation step size, each event particle should be treated with care as the condition outlined in Heisenberg's uncertainty principle (HUP) should also be satisfied. Within this quantum-classical regime, spatial delocalisations of individual ionisation event sites that are generated outside the target region are calculated, and particular attention is given to the validity of using classical transport methods in simulations of nanodosimetric parameters such as mean cluster size, first and second moments, variance and cumulative frequency of ionisation cluster-size probability distributions. This paper presents the comparison between conventionally calculated nanodosimetric quantities and the ones where interacting particles are treated semi-classically with spatial uncertainties satisfied by HUP. The simulated primary charged particles are electrons of energies between 100 eV and 1 keV in DNA equivalent target aqueous water volumes using GEANT4-DNA.

  13. Occupational external exposure to ionising radiation in France (2005-2011)

    International Nuclear Information System (INIS)

    The Institute for Radiological Protection and Nuclear Safety (IRSN) produces the French annual report on occupational exposure to ionising radiation, collecting all national data and aggregating the results according to a unique activity classification expected to be shared by all involved in personal dosimetric monitoring (employers, external dosimetry services and IRSN). Nearly 344 000 monitored workers were counted in France in 2011, with a collective dose of 64.24 man.Sv. The average annual dose (as calculated over the number of measurably exposed workers) differed among the main activity fields: 0.54 mSv in medical and veterinary activities, 1.18 mSv in the nuclear field, 1.60 mSv in non-nuclear industry and 0.47 mSv in research activities. Because of improved knowledge about worker activities, the results for year 2011 are detailed per activity sectors in each field. Lasting limitations prevent from having complete and reliable worker activity information. Solutions are considered to reduce the inaccuracy in the annually published statistics. The evolution of occupational external exposure to ionising radiation from 2005 to 2011 in France is then presented for the main activity fields. (authors)

  14. Glioblastoma stem cells: radiobiological response to ionising radiations of different qualities

    International Nuclear Information System (INIS)

    Glioblastoma multiform (GBM) is the most common and malignant primary brain tumour, with very poor prognosis. The high recurrence rate and failure of conventional treatments are expected to be related to the presence of radio-resistant cancer stem cells (CSCs) inside the tumour mass. CSCs can both self-renew and differentiate into the heterogeneous lineages of cancer cells. Recent evidence showed a higher effectiveness of C-ions and protons in inactivating CSCs, suggesting a potential advantage of Hadrontherapy compared with conventional radiotherapy for GBM treatment. To investigate the mechanisms involved in the molecular and cellular responses of CSCs to ionising radiations, two GBM stem cell (GSC) lines, named lines 1 and 83, which were derived from patients with different clinical outcomes and having different metabolic profiles (as shown by NMR spectroscopy), were irradiated with 137Cs photons and with protons or C-ions of 62 MeV u-1 in the dose range of 5- 40 Gy. The biological effects investigated were: cell death, cell cycle progression, and DNA damage induction and repair. Preliminary results show a different response to ionising radiation between the two GSC lines for the different end points investigated. Further experiments are in progress to consolidate the data and to get more insights on the influence of radiation quality. (authors)

  15. Glioblastoma stem cells: radiobiological response to ionising radiations of different qualities.

    Science.gov (United States)

    Pecchia, I; Dini, V; Ricci-Vitiani, L; Biffoni, M; Balduzzi, M; Fratini, E; Belli, M; Campa, A; Esposito, G; Cirrone, G; Romano, F; Stancampiano, C; Pelacchi, F; Pallini, R; Tabocchini, M A

    2015-09-01

    Glioblastoma multiforme (GBM) is the most common and malignant primary brain tumour, with very poor prognosis. The high recurrence rate and failure of conventional treatments are expected to be related to the presence of radio-resistant cancer stem cells (CSCs) inside the tumour mass. CSCs can both self-renew and differentiate into the heterogeneous lineages of cancer cells. Recent evidence showed a higher effectiveness of C-ions and protons in inactivating CSCs, suggesting a potential advantage of Hadrontherapy compared with conventional radiotherapy for GBM treatment. To investigate the mechanisms involved in the molecular and cellular responses of CSCs to ionising radiations, two GBM stem cell (GSC) lines, named lines 1 and 83, which were derived from patients with different clinical outcomes and having different metabolic profiles (as shown by NMR spectroscopy), were irradiated with (137)Cs photons and with protons or C-ions of 62 MeV u(-1) in the dose range of 5-40 Gy. The biological effects investigated were: cell death, cell cycle progression, and DNA damage induction and repair. Preliminary results show a different response to ionising radiation between the two GSC lines for the different end points investigated. Further experiments are in progress to consolidate the data and to get more insights on the influence of radiation quality. PMID:25969527

  16. Kinematically complete study on electron impact ionisation of aligned hydrogen molecules

    Energy Technology Data Exchange (ETDEWEB)

    Senftleben, Arne

    2009-10-28

    Within the work presented here, single ionisation of spatially aligned hydrogen molecules by 200 eV electrons was studied in a kinematically complete experiment. For the first time, a comprehensive set of fully differential cross sections (FDCS) was obtained for this process on a molecular target. The direction of the internuclear axis was derived from the fragment emission of post-collision dissociation of the residual H{sub 2}{sup +} ion. Therefore, a protonic fragment was detected in coincidence with the two final-state electrons using a dedicated reaction microscope and sophisticated data analysis. For direct ionisation into the ionic ground state, existing theoretical cross sections for aligned molecules were tested. Additionally, we observed molecular frame angular distributions of Auger electrons emitted through dissociative autoionisation of H{sub 2}. Earlier findings of kinematically incomplete experiments were reproduced, but the FDCS reveal structures so far unknown. Furthermore, for random alignment, differential cross sections at two distinct values of the mean internuclear distance were obtained, providing new arguments in the current discussion on the nature of discrepancies observed between atomic and molecular collisions. (orig.)

  17. Modelling the propagation of effects of chronic exposure to ionising radiation from individuals to populations

    Energy Technology Data Exchange (ETDEWEB)

    Alonzo, F. [Laboratory of Environmental Modelling, DEI/SECRE/LME, Institute of Radioprotection and Nuclear Safety (IRSN), Cadarache, Building 159, BP3, 13115 St-Paul-lez-Durance Cedex (France); Laboratory of Radioecology and Ecotoxicology, DEI/SECRE/LRE, Institute of Radioprotection and Nuclear Safety (IRSN), Cadarache Building 186, BP3, 13115 St-Paul-lez-Durance Cedex (France)], E-mail: frederic.alonzo@irsn.fr; Hertel-Aas, T. [Department of Plant and Environmental Sciences, P.O. Box 5003, Norwegian University of Life Sciences, 1432 Aas (Norway); Gilek, M. [School of Life Sciences, Soedertoern University College, 14189 Huddinge (Sweden); Gilbin, R. [Laboratory of Radioecology and Ecotoxicology, DEI/SECRE/LRE, Institute of Radioprotection and Nuclear Safety (IRSN), Cadarache Building 186, BP3, 13115 St-Paul-lez-Durance Cedex (France); Oughton, D.H. [Department of Plant and Environmental Sciences, P.O. Box 5003, Norwegian University of Life Sciences, 1432 Aas (Norway); Garnier-Laplace, J. [Laboratory of Radioecology and Ecotoxicology, DEI/SECRE/LRE, Institute of Radioprotection and Nuclear Safety (IRSN), Cadarache Building 186, BP3, 13115 St-Paul-lez-Durance Cedex (France)

    2008-09-15

    This study evaluated the potential effect of ionising radiation on population growth using simple population models and parameter values derived from chronic exposure experiments in two invertebrate species with contrasting life-history strategies. In the earthworm Eisenia fetida, models predicted increasing delay in population growth with increasing gamma dose rate (up to 0.6 generation times at 11 mGy h{sup -1}). Population extinction was predicted at 43 mGy h{sup -1}. In the microcrustacean Daphnia magna, models predicted increasing delay in population growth with increasing alpha dose rate (up to 0.8 generation times at 15.0 mGy h{sup -1}), only after two successive generations were exposed. The study examined population effects of changes in different individual endpoints (including survival, number of offspring produced and time to first reproduction). Models showed that the two species did not respond equally to equivalent levels of change, the fast growing daphnids being more susceptible to reduction in fecundity or delay in reproduction than the slow growing earthworms. This suggested that susceptibility of a population to ionising radiation cannot be considered independent of the species' life history.

  18. P-MaNGA Galaxies: Emission Lines Properties - Gas Ionisation and Chemical Abundances from Prototype Observations

    CERN Document Server

    Belfiore, F; Bundy, K; Thomas, D; Maraston, C; Wilkinson, D; Sánchez, S F; Bershady, M; Blanc, G A; Bothwell, M; Cales, S L; Coccato, L; Drory, N; Emsellem, E; Fu, H; Gelfand, J; Law, D; Masters, K; Parejko, J; Tremonti, C; Wake, D; Weijmans, A; Yan, R; Xiao, T; Zhang, K; Zheng, T; Bizyaev, D; Kinemuchi, K; Oravetz, D; Simmons, A

    2014-01-01

    MaNGA (Mapping Nearby Galaxies at Apache Point Observatory) is a SDSS-IV survey that will obtain spatially resolved spectroscopy from 3600 \\AA\\ to 10300 \\AA\\ for a representative sample of over 10000 nearby galaxies. In this paper we present the analysis of nebular emission line properties using observations of 14 galaxies obtained with P-MaNGA, a prototype of the MaNGA instrument. By using spatially resolved diagnostic diagrams we find extended star formation in galaxies that are centrally dominated by Seyfert/LINER-like emission, illustrating that galaxy characterisations based on single fibre spectra are necessarily incomplete. We observe extended (up to $\\rm 1 R_{e}$) LINER-like emission in the central regions of three galaxies. We make use of the $\\rm EW(H \\alpha)$ to argue that the observed emission is consistent with ionisation from hot evolved stars. Using stellar population indices we conclude that galactic regions which are ionised by a Seyfert/LINER-like radiation field are also devoid of recent st...

  19. Spatially resolved study of the physical properties of the ionised gas in NGC 595

    CERN Document Server

    Relano, M; Vilchez, J M; Kennicutt, R C

    2009-01-01

    We present Integral Field Spectroscopy (IFS) of NGC 595, one of the most luminous HII regions in M33. This type of observations allows studying the variation of the principal emission line ratios across the surface of the nebula. At each position of the field of view, we fit the main emission line features of the spectrum within the spectral range 3650-6990A, and create maps of the principal emission line ratios for the total surface of the region. The extinction map derived from the Balmer decrement and the absorbed H-alpha luminosity show good spatial correlation with the 24 micron emission from Spitzer. We also show here the capability of the IFS to study the existence of Wolf-Rayet (WR) stars, identifying the previously catalogued WRs and detecting a new candidate towards the north of the region. The ionisation structure of the region nicely follows the H-alpha shell morphology and is clearly related to the location of the central ionising stars. The electron density distribution does not show strong vari...

  20. On the effect of the ionising background on the Ly{\\alpha} forest autocorrelation function

    CERN Document Server

    Gontcho, Satya Gontcho A; Busca, Nicolás G

    2014-01-01

    An analytical framework is presented to understand the effects of a fluctuating intensity of the cosmic ionising background on the correlations of the Ly{\\alpha} forest transmission fraction measured in quasar spectra. In the absence of intensity fluctuations, the Ly{\\alpha} power spectrum should have the expected cold dark matter power spectrum with redshift distortions in the linear regime, with a bias factor b_{\\delta} and a redshift distortion parameter {\\beta} that depend on redshift but are independent of scale. The intensity fluctuations introduce a scale dependence in both b_{\\delta} and {\\beta}, but keeping their product b_{\\delta}{\\beta} fixed. Observations of the Ly{\\alpha} correlations and cross-correlations with radiation sources like those being done at present in the BOSS survey of SDSS-III (Busca et al. 2013; Slosar et al. 2013; Font-Ribera et al. 2014) have the potential to measure this scale dependence, which reflects the biasing properties of the sources and absorbers of the ionising backgr...

  1. Spectacular tails of ionised gas in the Virgo cluster galaxy NGC 4569

    CERN Document Server

    Boselli, A; Fossati, M; Boissier, S; Bomans, D; Consolandi, G; Anselmi, G; Cortese, L; Cote, P; Durrell, P; Ferrarese, L; Fumagalli, M; Gavazzi, G; Gwyn, S; Hensler, G; Sun, M; Toloba, E

    2016-01-01

    We obtained using MegaCam at the CFHT a deep narrow band Halpha+[NII] wide field image of NGC 4569, the brightest late-type galaxy in the Virgo cluster. The image reveals the presence of long tails of diffuse ionised gas without any associated stellar component extending from the disc of the galaxy up to ~ 80 kpc (projected distance) with a typical surface brightness of a few 10^-18 erg s-1 cm-2 arcsec-2. These features provide direct evidence that NGC 4569 is undergoing a ram presure stripping event. The image also shows a prominent 8 kpc spur of ionised gas associated to the nucleus that spectroscopic data identify as an outflow. With some assumptions on the 3D distribution of the gas, we use the Halpha surface brightness of these extended low surface brightness features to derive the density and the mass of the gas stripped during the interaction of the galaxy with the ICM. The comparison with ad-hoc chemo-spectrophotometric models of galaxy evolution indicates that the mass of the Halpha emitting gas in t...

  2. An important step forward in continuous spectroscopic imaging of ionising radiations using ASICs

    Energy Technology Data Exchange (ETDEWEB)

    Fessler, P. [11 rue Rabelais, 92170 Vanves (France); Coffin, J. [Institut de Recherches Subatomiques, B.P. 28, 67037 Strasbourg (France); Eberle, H. [Institut de Recherches Subatomiques, B.P. 28, 67037 Strasbourg (France); Raad Iseli, C. de [Smart Silicon Systems SA, Ch. de la Graviere 6, CH-1007 Lausanne (Switzerland); Hilt, B. [Universite de Haute-Alsace, GRPHE, 61, rue Albert Camus, 68093 Mulhouse (France); Huss, D. [Universite de Haute-Alsace, GRPHE, 61, rue Albert Camus, 68093 Mulhouse (France); Krummenacher, F. [Smart Silicon Systems SA, Ch. de la Graviere 6, CH-1007 Lausanne (Switzerland); Lutz, J.R. [Institut de Recherches Subatomiques, B.P. 28, 67037 Strasbourg (France); Prevot, G. [Institut de Recherches Subatomiques, B.P. 28, 67037 Strasbourg (France); Renouprez, A. [Institut de Recherche sur la Catalyse, 2 Avenue Albert Einstein, 69626 Villeurbanne (France); Sigward, M.H. [Institut de Recherches Subatomiques, B.P. 28, 67037 Strasbourg (France); Schwaller, B. [Universite de Haute-Alsace, GRPHE, 61, rue Albert Camus, 68093 Mulhouse (France); Voltolini, C. [Institut de Recherches Subatomiques, B.P. 28, 67037 Strasbourg (France)

    1999-01-21

    Characterization results are given for an original ASIC allowing continuous acquisition of ionising radiation images in spectroscopic mode. Ionising radiation imaging in general and spectroscopic imaging in particular must primarily be guided by the attempt to decrease statistical noise, which requires detection systems designed to allow very high counting rates. Any source of dead time must therefore be avoided. Thus, the use of on-line corrections of the inevitable dispersion of characteristics between the large number of electronic channels of the detection system, shall be precluded. Without claiming to achieve ultimate noise levels, the work described is focused on how to prevent good individual acquisition channel noise performance from being totally destroyed by the dispersion between channels without introducing dead times. With this goal, we developed an automatic charge amplifier output voltage offset compensation system which operates regardless of the cause of the offset (detector or electronic). The main performances of the system are the following: the input equivalent noise charge is 190 e rms (input non connected, peaking time 500 ns), the highest gain is 255 mV/fC, the peaking time is adjustable between 200 ns and 2 {mu}s and the power consumption is 10 mW per channel. The agreement between experimental data and theoretical simulation results is excellent.

  3. Correlation of the ionisation response at selected points of IC sensitive regions with SEE sensitivity parameters under pulsed laser irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Gordienko, A V; Mavritskii, O B; Egorov, A N; Pechenkin, A A; Savchenkov, D V [National Research Nuclear University ' ' MEPhI' ' (Russian Federation)

    2014-12-31

    The statistics of the ionisation response amplitude measured at selected points and their surroundings within sensitive regions of integrated circuits (ICs) under focused femtosecond laser irradiation is obtained for samples chosen from large batches of two types of ICs. A correlation between these data and the results of full-chip scanning is found for each type. The criteria for express validation of IC single-event effect (SEE) hardness based on ionisation response measurements at selected points are discussed. (laser applications and other topics in quantum electronics)

  4. On magnetospheric electron impact ionisation and dynamics in Titan's ram-side and polar ionosphere – a Cassini case study

    Directory of Open Access Journals (Sweden)

    G. R. Lewis

    2007-11-01

    Full Text Available We present data from the sixth Cassini flyby of Titan (T5, showing that the magnetosphere of Saturn strongly interacts with the moon's ionosphere and exo-ionosphere. A simple electron ionisation model provides a reasonable agreement with the altitude structure of the ionosphere. Furthermore, we suggest that the dense and cold exo-ionosphere (from the exobase at 1430 km and outward to several Titan radii from the surface can be explained by magnetospheric forcing and other transport processes whereas exospheric ionisation by impacting low energy electrons seems to play a minor role.

  5. High-resolution laser spectroscopy with the Collinear Resonance Ionisation Spectroscopy (CRIS) experiment at CERN-ISOLDE

    Science.gov (United States)

    Cocolios, T. E.; de Groote, R. P.; Billowes, J.; Bissell, M. L.; Budinčević, I.; Day Goodacre, T.; Farooq-Smith, G. J.; Fedosseev, V. N.; Flanagan, K. T.; Franchoo, S.; Garcia Ruiz, R. F.; Gins, W.; Heylen, H.; Kron, T.; Li, R.; Lynch, K. M.; Marsh, B. A.; Neyens, G.; Rossel, R. E.; Rothe, S.; Smith, A. J.; Stroke, H. H.; Wendt, K. D. A.; Wilkins, S. G.; Yang, X.

    2016-06-01

    The Collinear Resonance Ionisation Spectroscopy (CRIS) experiment at CERN has achieved high-resolution resonance ionisation laser spectroscopy with a full width at half maximum linewidth of 20(1) MHz for 219,221 Fr, and has measured isotopes as short lived as 5 ms with 214 Fr. This development allows for greater precision in the study of hyperfine structures and isotope shifts, as well as a higher selectivity of single-isotope, even single-isomer, beams. These achievements are linked with the development of a new laser laboratory and new data-acquisition systems.

  6. Study and optimization of the ionisation channel in the Edelweiss dark matter direct detection experiment; Etude et optimisation de la voie ionisation dans l'experience Edelweiss de detection directe de la matiere noire

    Energy Technology Data Exchange (ETDEWEB)

    Censier, B

    2006-02-15

    The EDELWEISS experiment is aiming at the detection of Weakly Interactive Massive Particles (WIMPs), today's most favoured candidates for solving the dark matter issue. Background ionising particles are identified thanks to the simultaneous measurement of heat and ionisation in the detectors. The main limitation to this method is coming from the ionisation measurement, charge collection being less efficient in some part of the detectors known as 'dead' areas. The specificity of the measurement is due to the use of very low temperatures and low collection fields. This thesis is dedicated to the study of carrier trapping. It involves time-resolved charge measurements as well as a simulation code adapted to the specific physical conditions. We first present results concerning charge trapping at the free surfaces of the detectors. Our method allows to build a surface-charge in a controlled manner by irradiation with a strong radioactive source. This charge is then characterised with a weaker source which acts as a probe. In a second part of the work, bulk-trapping characteristics are deduced from charge collection efficiency measurements, and by an original method based on event localisation in the detector. The results show that a large proportion of the doping impurities are ionised, as indicated independently by the study of degradation by space-charge build-up. In this last part, near-electrodes areas are found to contain large densities of charged trapping centres, in connection with dead-layer effects. (author)

  7. Absorbed dose in ion beams: comparison of ionisation- and fluence-based measurements

    International Nuclear Information System (INIS)

    A direct comparison measurement of fluorescent nuclear track detectors (FNTDs) and a thimble ionisation chamber is presented. Irradiations were performed using monoenergetic protons (142.66 MeV, φ=3x106 cm-2) and carbon ions (270.55 MeV u-1, φ=3x106 cm-2). It was found that absorbed dose to water values as determined by fluence measurements using FNTDs are, in case of protons, in good agreement (2.4 %) with ionisation chamber measurements, if slower protons and Helium secondaries were accounted for by an effective stopping power. For carbon, however, a significant discrepancy of 4.5 % was seen, which could not be explained by fragmentation, uncertainties or experimental design. The results rather suggest a W-value of 32.10 eV±2.6 %. Additionally, the abundance of secondary protons expected from Monte-Carlo transport simulation was not observed. FNTDs are able to yield correct dose estimation for protons. The assumption of a monoenergetic beam, even in the entrance channel, is invalid since slower protons and secondaries contribute significantly and an effective stopping power has to be employed. These corrections account for the discrepancies seen in the authors' previous experiments. Since the FNTD fluorescent track amplitude depends on the particle species and energy, the effective stopping power might be estimated from the intensity histogram of the particle tracks. For carbon ions, however, secondary particles did not fully account for the discrepancies found. Considering the detection efficiency of FNTD technology, it seems unlikely that a significant portion of tracks were not registered. This might stimulate discussions on the accuracy of the kQ,Q0 factor for carbon beams. Since the stopping power in this energy range is known quite accurately (1-2 %), one might question the currently used constant Wair value of 34.50 ± 0.52 eV (1.5 %)(14). The presented findings would imply a Wair value of 32.10±0.83 eV (2.6 %). This uncertainty includes all

  8. First Glossary of Modern Physics and Ionising Radiation Protection in Croatian

    International Nuclear Information System (INIS)

    Motivation and encouragement for the Glossary were given as the research theme for the joint seminar between the Faculty of Electrical Engineering and Computing and Rudjer Boskovic Institute, within a postgraduate course subject ''Detectors and electronic instrumentation for particle physics''. A basic motivation is due to a lack of specialized literature in Croatian language in the field of protection of ionising radiation as well as the incompleteness of Croatian terminology in the same field. That is a general problem all over the World because the most glossaries are usually connected either with nuclear power plants or with an application of ionising radiation in medicine. On the other hand, a necessity for the specialized literature for radiation protection which follows a development of modern particle physics and its detection technique is rapidly growing up. A work and development on the Glossary were faced with serious difficulties, since various translations of foreign words and acronyms have already been used by various authors in Croatian literature. Different interpretations of the same term or concept, from diverse sources, had to be very often reconciled. However, the biggest challenge was finding proper Croatian words for the foreign terms, concepts, properties, and quantities which have not yet been commonly used so far in Croatian papers or/and Croatian legislative acts. According to our knowledge this seems to be the first comprehensive Glossary, describing the field of ionising radiation protection and bringing of 300 related entries (terms and guidelines). That is, certainly, the first characteristic Thesaurus in Croatian which includes background of modern physics and chemistry, particle phenomenology and its measurement, all dedicated to the radiological protection of workers, environment and people of the World. A Glossary brings a wide spectrum of terms of broad area of chemistry, radiation protection, nuclear and particle physics. A

  9. Genome-Wide Analysis and Characterization of Aux/IAA Family Genes in Brassica rapa.

    Directory of Open Access Journals (Sweden)

    Parameswari Paul

    Full Text Available Auxins are the key players in plant growth development involving leaf formation, phototropism, root, fruit and embryo development. Auxin/Indole-3-Acetic Acid (Aux/IAA are early auxin response genes noted as transcriptional repressors in plant auxin signaling. However, many studies focus on Aux/ARF gene families and much less is known about the Aux/IAA gene family in Brassica rapa (B. rapa. Here we performed a comprehensive genome-wide analysis and identified 55 Aux/IAA genes in B. rapa using four conserved motifs of Aux/IAA family (PF02309. Chromosomal mapping of the B. rapa Aux/IAA (BrIAA genes facilitated understanding cluster rearrangement of the crucifer building blocks in the genome. Phylogenetic analysis of BrIAA with Arabidopsis thaliana, Oryza sativa and Zea mays identified 51 sister pairs including 15 same species (BrIAA-BrIAA and 36 cross species (BrIAA-AtIAA IAA genes. Among the 55 BrIAA genes, expression of 43 and 45 genes were verified using Genebank B. rapa ESTs and in home developed microarray data from mature leaves of Chiifu and RcBr lines. Despite their huge morphological difference, tissue specific expression analysis of BrIAA genes between the parental lines Chiifu and RcBr showed that the genes followed a similar pattern of expression during leaf development and a different pattern during bud, flower and siliqua development stages. The response of the BrIAA genes to abiotic and auxin stress at different time intervals revealed their involvement in stress response. Single Nucleotide Polymorphisms between IAA genes of reference genome Chiifu and RcBr were focused and identified. Our study examines the scope of conservation and divergence of Aux/IAA genes and their structures in B. rapa. Analyzing the expression and structural variation between two parental lines will significantly contribute to functional genomics of Brassica crops and we belive our study would provide a foundation in understanding the Aux/IAA genes in B. rapa.

  10. Genome-Wide Analysis and Characterization of Aux/IAA Family Genes in Brassica rapa.

    Science.gov (United States)

    Paul, Parameswari; Dhandapani, Vignesh; Rameneni, Jana Jeevan; Li, Xiaonan; Sivanandhan, Ganesan; Choi, Su Ryun; Pang, Wenxing; Im, Subin; Lim, Yong Pyo

    2016-01-01

    Auxins are the key players in plant growth development involving leaf formation, phototropism, root, fruit and embryo development. Auxin/Indole-3-Acetic Acid (Aux/IAA) are early auxin response genes noted as transcriptional repressors in plant auxin signaling. However, many studies focus on Aux/ARF gene families and much less is known about the Aux/IAA gene family in Brassica rapa (B. rapa). Here we performed a comprehensive genome-wide analysis and identified 55 Aux/IAA genes in B. rapa using four conserved motifs of Aux/IAA family (PF02309). Chromosomal mapping of the B. rapa Aux/IAA (BrIAA) genes facilitated understanding cluster rearrangement of the crucifer building blocks in the genome. Phylogenetic analysis of BrIAA with Arabidopsis thaliana, Oryza sativa and Zea mays identified 51 sister pairs including 15 same species (BrIAA-BrIAA) and 36 cross species (BrIAA-AtIAA) IAA genes. Among the 55 BrIAA genes, expression of 43 and 45 genes were verified using Genebank B. rapa ESTs and in home developed microarray data from mature leaves of Chiifu and RcBr lines. Despite their huge morphological difference, tissue specific expression analysis of BrIAA genes between the parental lines Chiifu and RcBr showed that the genes followed a similar pattern of expression during leaf development and a different pattern during bud, flower and siliqua development stages. The response of the BrIAA genes to abiotic and auxin stress at different time intervals revealed their involvement in stress response. Single Nucleotide Polymorphisms between IAA genes of reference genome Chiifu and RcBr were focused and identified. Our study examines the scope of conservation and divergence of Aux/IAA genes and their structures in B. rapa. Analyzing the expression and structural variation between two parental lines will significantly contribute to functional genomics of Brassica crops and we belive our study would provide a foundation in understanding the Aux/IAA genes in B. rapa. PMID

  11. Ti1-xAux Alloys: Hard Biocompatible Metals and Their Possible Applications

    Science.gov (United States)

    Svanidze, Eteri; Besara, Tiglet; Ozaydin, M. Fevzi; Xin, Yan; Han, Ke; Liang, Hong; Siegrist, Theo; Morosan, Emilia

    2015-03-01

    The search for new hard materials is often challenging from both theoretical and experimental points of view. Furthermore, using materials for biomedical applications calls for alloys with high biocompatibility which are even more sparse. The Ti1-xAux (0 . 22 dental, and prosthetic applications, where they could be used as both permanent and temporary components. Additionally, the ability of Ti1-xAux alloys to adhere to ceramic parts could reduce the weight and cost of these components. The work at Rice was supported by NSF DMR 0847681 (E.M. and E.S.).

  12. Report of transparency and nuclear safety 2007 CEA Fontenay aux Roses; Rapport transparence et securite nucleaire 2007 CEA Fontenay aux Roses

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-01

    This report presents the activities of the CEA Center of Fontenay aux roses for the year 2007. After many years of decommissioning and dismantling of nuclear installations, the Center is now devoted (since 2005) to the development of research programmes on biology and biomedical technologies. The actions concerning the safety, the radiation protection, the significant events, the release control and the environmental impacts and the wastes stored on the center are discussed. (A.L.B.)

  13. Spin-Orbit Larmor Clock for Ionisation Times in One-Photon and Strong-Field Regimes

    CERN Document Server

    Kaushal, Jivesh; Torlina, Lisa; Ivanov, Misha; Smirnova, Olga

    2015-01-01

    Photoionisation is a process where absorption of one or several photons liberates an electron and creates a hole in a quantum system, such as an atom or a molecule. Is it faster to remove an electron using one or many photons, and how to define this time? Here we introduce a clock that allows us to define ionisation time for both one-photon and many-photon ionisation regimes. The clock uses the interaction of the electron or hole spin with the magnetic field created by their orbital motion, known as the spin-orbit interaction. The angle of spin precession in the magnetic field records time. We use the combination of analytical theory and ab-initio calculations to show how ionisation delay depends on the number of absorbed photons, how it appears in the experiment and what electron dynamics it signifies. In particular, we apply our method to calculate the derived time delays in tunnelling regime of strong-field ionisation.

  14. Time-dependent hydrogen ionisation in 3D simulations of the solar chromosphere. Methods and first results

    NARCIS (Netherlands)

    Leenaarts, J.; Wedemeyer-Bohm, S.

    2006-01-01

    Context. The hydrogen ionisation degree deviates substantially from statistical equilibrium under the conditions of the solar chromosphere. A realistic description of this atmospheric layer thus must account for time-dependent non-equilibrium effects. Aims. Advancing the realism of numerical simulat

  15. The effect of intergalactic helium on hydrogen reionisation: implications for the sources of ionising photons at z > 6

    CERN Document Server

    Ciardi, B; Maselli, A; Graziani, L

    2011-01-01

    We investigate the effect of helium on hydrogen reionisation using a hydrodynamical simulation combined with the cosmological radiative transfer code CRASH. The simulations are run in a 35.12/h comoving Mpc box using a variety of assumptions for the amplitude and power-law extreme-UV (EUV) spectral index, alpha, of the ionising emissivity. We use an empirically motivated prescription for ionising sources which ensures all of the models are consistent with constraints on the Thomson scattering optical depth and the hydrogen photo-ionisation rate at z=6. The inclusion of helium slightly delays reionisation due to the small number of ionising photons which reionise neutral helium instead of hydrogen. However, helium has a significant impact on the thermal state of the IGM. Models with alpha=3 produce IGM temperatures at the mean density at z=6 which are about 20 % higher compared to models without helium photo-heating. Harder EUV indices produce even larger IGM temperature boosts. A comparison to recent observat...

  16. Serum ionised calcium and cardiovascular disease in 45-years old men and women followed for 18 years

    DEFF Research Database (Denmark)

    Ogard, Christina Gerlach; Petersen, Janne; Jørgensen, Torben;

    2006-01-01

    High level of total serum calcium within the normal range has been associated with increased cardiovascular risk. We wanted to evaluate whether the physiological active ionised form of calcium also was a risk factor for cardiovascular disease (CVD). Methods: A total of 974 participants from...

  17. Determination of kava lactones in food supplements by liquid chromatography-atmospheric pressure chemical ionisation tandem mass spectrometry

    NARCIS (Netherlands)

    Bobeldijk, I.; Boonzaaijer, G.; Spies-Faber, E.J.; Vaes, W.H.J.

    2005-01-01

    Reversed-phase liquid chromatography and detection with atmospheric pressure chemical ionisation tandem mass spectrometry was used for the determination of kava extracts in herbal mixtures. One percent of kava extract can be detected, corresponding to approximately 0.05-0.2 mg/g of the individual ka

  18. Characterisation of exposure to non-ionising electromagnetic fields in the Spanish INMA birth cohort: Study protocol

    NARCIS (Netherlands)

    M. Gallastegi (Mara); M. Guxens (Mònica ); A. Jiménez-Zabala (Ana); I. Calvente (Irene); M. Fernández (Marta); L. Birks (Laura); B. Struchen (Benjamin); M. Vrijheid (Martine); M. Estarlich (Marisa); M.F. Fernandez (Mariana); M. Torrent (Maties); F. Ballester (Ferran); J.J. Aurrekoetxea (Juan José); J. Ibarluzea (Jesús); D. Guerra (David); J. González (Julián); M. Röösli (Martin); L. Santa-Marina (Loreto)

    2016-01-01

    textabstractBackground: Analysis of the association between exposure to electromagnetic fields of non-ionising radiation (EMF-NIR) and health in children and adolescents is hindered by the limited availability of data, mainly due to the difficulties on the exposure assessment. This study protocol de

  19. Brain Radiation Information Data Exchange (BRIDE): Integration of experimental data from low-dose ionising radiation research for pathway discovery

    NARCIS (Netherlands)

    C. Karapiperis (Christos); S.J. Kempf (Stefan J.); R. Quintens (Roel); O. Azimzadeh (Omid); V.L. Vidal (Victoria Linares); S. Pazzaglia; D. Bazyka (Dimitry); P.G. Mastroberardino (Pier); Z.G. Scouras (Zacharias G.); S. Tapio (Soile); M.A. Benotmane (Mohammed Abderrafi); C.A. Ouzounis (Christos A.)

    2016-01-01

    textabstractBackground: The underlying molecular processes representing stress responses to low-dose ionising radiation (LDIR) in mammals are just beginning to be understood. In particular, LDIR effects on the brain and their possible association with neurodegenerative disease are currently being ex

  20. Beer fingerprinting by Matrix-Assisted Laser Desorption-Ionisation-Time of Flight Mass Spectrometry.

    Science.gov (United States)

    Šedo, Ondrej; Márová, Ivana; Zdráhal, Zbyněk

    2012-11-15

    A method allowing parallel fingerprinting of proteins and maltooligosaccharides directly from untreated beer samples is presented. These two classes of compounds were detected by Matrix-Assisted Laser Desorption-Ionisation-Time of Flight-Mass Spectrometry (MALDI-TOF-MS) analysis of beer mixed with 2,5-dihydroxybenzoic acid solution. The maltooligosaccharide profiles acquired from the MALDI sample spot center were not found characteristic for beers of different source and technology. On the other hand, according to profiles containing protein signals acquired from crystals formed on the border of the MALDI sample spot, we were able to distinguish beer samples of the same brand produced by different breweries. The discriminatory abilities of the method were further examined on a set of 17 lager beers, where the fingerprints containing protein signals enabled resolution of majority of examined brands. We propose MALDI-TOF-MS profiling as a rapid tool for beer brewing technology process monitoring, quality control, and determination of beer authenticity.

  1. Evidence for dust emission in the Warm Ionised Medium using WHAM data

    CERN Document Server

    Lagache, G; Reynolds, R J; Tufte, S L

    1999-01-01

    We have used the WHAM H_alpha survey and Leiden/Dwingeloo HI data to decompose the Far-infrared emission (from 100 to 1000 micron) at high Galactic latitude into components associated with the Warm Ionised Medium (WIM) and the Warm Neutral Medium (WNM). This decomposition is possible for the first time thanks to preliminary WHAM data that cover a significant fraction of the sky (about 10%). We confirm the first detection of dust emission from the WIM (Lagache et al. 1999) and show that the WIM dust temperature and emissivity are very similar to those in the WNM. The analysis suggests moreover that about 25% of the far-IR dust emission at high galactic latitude is uncorrelated with the HI gas. The decomposition again reveals a Cosmic Far-Infrared Background (CFIRB) which is determined for the first time from 100 to 1000 micron using two independant gas tracers.

  2. Determination of potato glycoalkaloids using high-pressure liquid chromatography-electrospray ionisation/mass spectrometry.

    Science.gov (United States)

    Matsuda, Fumio; Morino, Keiko; Miyazawa, Haruna; Miyashita, Masahiro; Miyagawa, Hisashi

    2004-01-01

    A method for quantifying two toxic glycoalkaloids, alpha-solanine and alpha-chaconine, in potato (Solanum tuberosum) tuber tissue was developed using HPLC-electrospray ionisation (ESI)/MS. Potato samples were extracted with 5% aqueous acetic acid, and the extracts were subjected directly to HPLC-ESI/MS after filtration. By determining the intensities of the protonated molecules of alpha-solanine (m/z 868) and alpha-chaconine (m/z 852) using selected ion monitoring (positive ion mode), a sensitive assay was attained with detection limits of 38 and 14 ppb for the two glycoalkaloids, respectively. The high sensitivity and selectivity of MS detection effectively reduced the time of analysis thus enabling a high throughput assay of glycoalkaloids in potato tubers.

  3. Applying the ionising radiation regulations to radon in the UK workplace

    International Nuclear Information System (INIS)

    As a response to the identification of a health risk from workplace radon in the UK, the Ionising Radiations Regulations include the protection of workers from excessive levels of radon. Employers are required to make risk assessments, and the interpretation of the Health and Safety Executive is that the regulations apply to workplace premises in locations already designated as Radon Affected Areas for domestic purposes, with the difference that in workplaces, it is the maximum winter radon concentration rather than the annual average which is the parameter of interest. This paper discusses the rationale behind the current regulatory environment, outlines the role and duties of Accredited Radiation Protection Advisers and summarises the strategies necessary to conform to the regulations. (authors)

  4. Chemical profile of mango (Mangifera indica L.) using electrospray ionisation mass spectrometry (ESI-MS).

    Science.gov (United States)

    Oliveira, Bruno G; Costa, Helber B; Ventura, José A; Kondratyuk, Tamara P; Barroso, Maria E S; Correia, Radigya M; Pimentel, Elisângela F; Pinto, Fernanda E; Endringer, Denise C; Romão, Wanderson

    2016-08-01

    Mangifera indica L., mango fruit, is consumed as a dietary supplement with purported health benefits; it is widely used in the food industry. Herein, the chemical profile of the Ubá mango at four distinct maturation stages was evaluated during the process of growth and maturity using negative-ion mode electrospray ionisation Fourier transform ion cyclotron resonance mass spectrometry (ESI(-)FT-ICR MS) and physicochemical characterisation analysis (total titratable acidity (TA), total soluble solids (TSS), TSS/TA ratio, and total polyphenolic content). Primary (organic acids and sugars) and secondary metabolites (polyphenolic compounds) were mostly identified in the third maturation stage, thus indicating the best stage for harvesting and consuming the fruit. In addition, the potential cancer chemoprevention of the secondary metabolites (phenolic extracts obtained from mango samples) was evaluated using the induction of quinone reductase activity, concluding that fruit polyphenols have the potential for cancer chemoprevention. PMID:26988473

  5. Electrifying atmospheres charging, ionisation and lightning in the solar system and beyond

    CERN Document Server

    Aplin, Karen L

    2013-01-01

    Electrical processes take place in all planetary atmospheres. There is evidence for lightning on Venus, Jupiter, Saturn, Uranus and Neptune, it is possible on Mars and Titan, and cosmic rays ionise every atmosphere, leading to charged droplets and particles. Controversy surrounds the role of atmospheric electricity in physical climate processes on Earth; here, a comparative approach is employed to review the role of electrification in the atmospheres of other planets and their moons. This book reviews the theory, and, where available, measurements, of planetary atmospheric electricity, taken to include ion production and ion-aerosol interactions. The conditions necessary for a global atmospheric electric circuit similar to Earth’s, and the likelihood of meeting these conditions in other planetary atmospheres, are briefly discussed. Atmospheric electrification is more important at planets receiving little solar radiation, increasing the relative significance of electrical forces. Nucleation onto atmospheric ...

  6. A search for non-baryonic dark matter using an ionisation bolometer in the edelweiss experiment

    International Nuclear Information System (INIS)

    The EDELWEISS experiment is an underground direct-detection search for hypothetical supersymmetric WIMPs that might solve the problem of dark matter. We have employed a cryogenic 70 g germanium ionisation bolometer, in which a WIMP would scatter elastically off a nucleus, creating both a heat and an ionisation signal. To offset the various electronic noises present in our necessarily small signals, we have s applied an optimal filtering technique in the frequency domain. This allows us to reach resolutions of 1.2 keV FWHM at 122 keV on north channels. It also provides good separation right down to low energies between the expected signal of nuclear recoils, and the photonic background of electron recoils which ionize more for a given energy. Calibration data show that we are able to reject 99.7 % of this background, while keeping 95% of the signal. However, our 1.17 kg.days of data searching for WIMPs show a third population encroaching on the expected signal. This is probably due to low energy photons or electrons interacting in the outer layers of the crystal, where charges are incompletely collected. Nevertheless, by trading off half of the conserved signal, we still manage to reject 98.5 % of the background. Thus the raw rate of 40 evts/d/kg/keV yields a conservative 90 % upper limit on the signal of 0.6 evts/d/kg/keV. This represents nearly a three orders of magnitude improvement for EDELWEISS, and puts the predicted supersymmetric phase space within two orders of magnitude. (author)

  7. Chemically modified carbon nanotubes as material enhanced laser desorption ionisation (MELDI) material in protein profiling

    International Nuclear Information System (INIS)

    Biomarkers play a potential role in the early detection and diagnosis of a disease. Our aim is to derivatize carbon nanotubes for exploration of the differences in human body fluids e.g. serum, through matrix assisted laser desorption ionisation/time of flight mass spectrometry (MALDI/TOF-MS) that can be related to disease and subsequently to be employed in the biomarker discovery process. This application we termed as the material enhanced laser desorption ionisation (MELDI). The versatility of this technology is meant to increase the amount of information from biological samples on the protein level, which will have a major impact to serve the cause of diagnostic markers. Serum peptides and proteins are immobilized on derivatized carbon nanotubes, which function as binding material. Protein-loaded suspension is placed on a stainless steel target or buckypaper on aluminum target for direct analysis with MALDI-MS. The elution method to wash the bound proteins from carbon nanotubes was employed to compare with the direct analysis procedure. Elution is carried out by MALDI matrix solution to get them out of the entangled nanotubes, which are difficult to desorb by laser due to the complex nanotube structures. The advantage of these optimized methods compared to the conventional screening methods is the improved sensitivity, selectivity and the short analysis time without prior albumin and immunoglobulin depletion. The comparison of similarly modified diamond and carbon nanotubes exhibit differences in their nature to bind the proteins out of serum due to the differences in their physical characteristics. Infrared (IR) spectroscopy provided hint for the presence of tertiary amine peak at the crucial chemical step of iminodiacetic acid addition to acid chloride functionality on carbon nanotubes. Atomic absorption spectroscopy (AAS) was utilized to quantitatively measure the copper capacity of these derivatized carbon nanotubes which is a direct measure of capacity of

  8. Application of Lithium Attachment Mass Spectrometry for Knudsen Evaporation and Chemical Ionisation Mass Spectrometry (KEMS, CIMS)

    Science.gov (United States)

    Bannan, Thomas; Booth, A. Murray; Alfarra, Rami; Bacak, Asan; Pericval, Carl

    2016-04-01

    Lithium ion attachment mass spectrometry provides a non-specific, non-fragmenting and sensitive method for detection of volatile species in the gas phase. The design, manufacture, and results from lithium ion attachment ionisation sources for two mass spectrometry systems are presented. Trace gas analysis is investigated using a modified Chemical Ionization Mass Spectrometer (CIMS) and vapour pressure (VP) measurements using a modified Knudsen Effusion Mass Spectrometer (KEMS) are presented. The Li+ modified CIMS provided limits of detection of 4 ppt for acetone, 0.2 ppt for formic acid, 15 ppt for nitric acid and 120 ppt from ammonia. Despite improvements, the problem of burnout remained persistent. The Li+ CIMS would unlikely be suitable for field or aircraft work, but could be appropriate for certain lab applications. The KEMS currently utilizes an electron impact (EI) ionisation source which provides a highly sensitive source, with the drawback of fragmentation of ionized molecules (Booth et al., 2009). Using Li+ KEMS the VP of samples can be measured without fragmentation and can therefore be used to identify VPs of individual components in mixtures. The validity of using Li+ for determining the VP of mixtures was tested by making single component VP measurements, which showed good agreement with EI measurements of Poly ethylene glycol (PEG) 3 and PEG 4, both when individually measured and when mixed. The Li+ KEMS was then used to investigate a system of atmospheric relevance, α-pinene secondary organic aerosol, generated in a reaction chamber (Alfarra et al., 2012). The VPs of the individual components from this generated sample are within the range we expect for compounds capable of partitioning between the particle and gas phase of an aerosol (0.1-10-5 Pa). Li+ source has a calculated sensitivity approximately 75 times less than that of EI, but the lack of fragmentation using the Li+ source is a significant advantage.

  9. EPR spectroscopy for the detection of foods treated with ionising radiation

    International Nuclear Information System (INIS)

    The advantage of electron paramagnetic resonance spectroscopy (EPR or ESR) as a tool for the control of irradiated food lies in its sensitivity and accuracy. Ionising radiation produces, in irradiated materials, paramagnetic species of different kinds, i.e. radicals, radical-ions and paramagnetic centres, which can be measured by EPR but most of them are not stable enough to be used for the detection of irradiation. It is because radiation-induced paramagnetic species are thermodynamically less stable than surrounding molecules and take part in fast radiolytic reactions leading to the formation of final diamagnetic products that they are not detectable by the EPR method. Most of organic radicals produced by radiation in the liquid phase ae unstable but if the unpaired electron is incorporated into the complex polymeric system as in peptides and polysaccharides and is structurally isolated from the water, its stability is markedly increased. Since 1954 it is known that ionising radiation produces paramagnetic entities in biological materials, cells and tissues and some are stable enough to be observed by EPR spectroscopy at room temperature. The present paper describes and discusses that part of results obtained by this group during the period of ADMIT activity (1989-94) which are original and may be useful to those who will be working in the near future on the development of uniform control systems for the detection of irradiated food. The intention was to focus attention on these facts and data which influence the certainty of the detection in both positive and negative manner. (author)

  10. Response of the Nrf2 protection system in human monocytic cells after ionising irradiation

    International Nuclear Information System (INIS)

    In response to reactive oxygen species (ROS) or electrophiles, the transcription factor nuclear factor-erythroid 2 (NF-E2)-related factor 2 (Nrf2) rapidly trans-locates into the nucleus and induces the expression of various antioxidant genes, such as heme oxygenase-1 (HO-1). Low linear energy transfer (LET) ionising radiations such as X-rays generate ROS, which cause biological damage. However, little is known about whether the Nrf2 system in human monocytic cells is activated by low LET ionising irradiation. Therefore, in this study, the response of the Nrf2 system to X-irradiation in human monocytic THP1 cells was investigated. Following exposure of THP1 cells to X-rays (1-5 Gy), intracellular ROS levels were measured using 2',7'-dichlorodihydro-fluorescein diacetate, Nrf2 localisation was determined using immunofluorescence staining and HO-1 mRNA and protein expression were examined. Although ROS were generated by irradiation in a dose-dependent manner, they disappeared immediately after irradiation. Nrf2 translocation into the nucleus was observed 6 h after 5 Gy X irradiation but was not detected following 1-2 Gy irradiation or in non-irradiated controls. HO-1 expression was significantly higher in 5 Gy-irradiated cells after 24 h than in non-irradiated controls. These results indicate that high-dose irradiation (5 Gy) activates Nrf2 and that the Nrf2 protection system may function from 24 h after irradiation in human monocytic cells. (authors)

  11. Chemically modified carbon nanotubes as material enhanced laser desorption ionisation (MELDI) material in protein profiling

    Energy Technology Data Exchange (ETDEWEB)

    Najam-ul-Haq, M. [Institute of Analytical Chemistry and Radiochemistry, Leopold-Franzens University, Innrain 52a, A-6020 Innsbruck (Austria); Rainer, M. [Institute of Analytical Chemistry and Radiochemistry, Leopold-Franzens University, Innrain 52a, A-6020 Innsbruck (Austria); Schwarzenauer, T. [Institute of Analytical Chemistry and Radiochemistry, Leopold-Franzens University, Innrain 52a, A-6020 Innsbruck (Austria); Huck, C.W. [Institute of Analytical Chemistry and Radiochemistry, Leopold-Franzens University, Innrain 52a, A-6020 Innsbruck (Austria)]. E-mail: christian.w.huck@uibk.ac.at; Bonn, G.K. [Institute of Analytical Chemistry and Radiochemistry, Leopold-Franzens University, Innrain 52a, A-6020 Innsbruck (Austria)

    2006-03-02

    Biomarkers play a potential role in the early detection and diagnosis of a disease. Our aim is to derivatize carbon nanotubes for exploration of the differences in human body fluids e.g. serum, through matrix assisted laser desorption ionisation/time of flight mass spectrometry (MALDI/TOF-MS) that can be related to disease and subsequently to be employed in the biomarker discovery process. This application we termed as the material enhanced laser desorption ionisation (MELDI). The versatility of this technology is meant to increase the amount of information from biological samples on the protein level, which will have a major impact to serve the cause of diagnostic markers. Serum peptides and proteins are immobilized on derivatized carbon nanotubes, which function as binding material. Protein-loaded suspension is placed on a stainless steel target or buckypaper on aluminum target for direct analysis with MALDI-MS. The elution method to wash the bound proteins from carbon nanotubes was employed to compare with the direct analysis procedure. Elution is carried out by MALDI matrix solution to get them out of the entangled nanotubes, which are difficult to desorb by laser due to the complex nanotube structures. The advantage of these optimized methods compared to the conventional screening methods is the improved sensitivity, selectivity and the short analysis time without prior albumin and immunoglobulin depletion. The comparison of similarly modified diamond and carbon nanotubes exhibit differences in their nature to bind the proteins out of serum due to the differences in their physical characteristics. Infrared (IR) spectroscopy provided hint for the presence of tertiary amine peak at the crucial chemical step of iminodiacetic acid addition to acid chloride functionality on carbon nanotubes. Atomic absorption spectroscopy (AAS) was utilized to quantitatively measure the copper capacity of these derivatized carbon nanotubes which is a direct measure of capacity of

  12. In vivo EPR dosimetry to quantify exposures to clinically significant doses of ionising radiation

    International Nuclear Information System (INIS)

    As a result of terrorism, accident or war, populations potentially can be exposed to doses of ionising radiation that could cause direct clinical effects within days or weeks. There is a critical need to determine the magnitude of the exposure to individuals so that those with significant risk can have appropriate procedures initiated immediately, while those without a significant probability of acute effects can be reassured and removed from the need for further consideration in the medical/emergency system. It is extremely unlikely that adequate dosemeters will be worn by the potential victims, and it also will be unlikely that prompt and accurate dose reconstruction at the level of individuals will be possible. Therefore, there is a critical need for a method to measure the dose from radiation-induced effects that occur within the individual. In vivo EPR measurements of radiation-induced changes in the enamel of teeth is a method, perhaps the only such method, which can differentiate among doses sufficiently to classify individuals into categories for treatment with sufficient accuracy to facilitate decisions on medical treatment. In its current state, the in vivo EPR dosemeter can provide estimates of absorbed dose of ± 0.5 Gy in the range from 1 to >10 Gy. The lower limit and the precision are expected to improve, with improvements in the resonator and the algorithm for acquiring and calculating the dose. In its current state of development, the method is already sufficient for decision-making action for individuals with regard to acute effects from exposure to ionising radiation for most applications related to terrorism, accidents or nuclear warfare. (authors)

  13. The ionising radiations: a daily reality Las radiaciones ionizantes: una realidad cotidiana

    Directory of Open Access Journals (Sweden)

    Eduardo Gallego Díaz

    2010-12-01

    Full Text Available This paper introduce the nature of the radioactive substances and of the ionising radiation, the effects that they cause on the matter and the available media for their detection and measure, as well as the sources of natural radiation, to which the human being are exposed. Next, in the more detailed part of this paper, it is described the wide range of ionising radiations uses in: medicine, agriculture, earth sciences, biology and in some other scientific fields, that allow to pose its impact in the perspective of facing the ones from natural sources. The article concludes that for avoiding damages it is necessary proper protection against the radioactive substances, but avoiding limitation their beneficial uses in the various ranges described. For finishing this paper, the basic principles of radiation protection are described, due to they are the its principal aim.Este trabajo introduce la naturaleza de las sustancias radiactivas y de la radiación ionizante, los efectos que causa sobre la materia y los medios disponibles para su detección y medida, así como las fuentes de radiación naturales a las que los seres humanos estamos expuestos. Seguidamente, en el apartado más amplio del trabajo, se describen las múltiples aplicaciones de las radiaciones ionizantes en la medicina, la agricultura, la industria, las ciencias de la tierra, la biología y otras ramas, lo que permite poder poner su impacto en perspectiva frente al de las fuentes naturales. La tesis final del artículo es que para evitar sufrir daños resulta necesario protegerse adecuadamente de los efectos nocivos de la radiación y las sustancias radiactivas, pero sin limitar innecesariamente su utilización beneficiosa en los numerosos ámbitos descritos. Ese es el objetivo fundamental de la protección radiológica, cuyos principios básicos se presentan para terminar.

  14. Regulations concerning radiation protection and survey; Donnees de la surveillance et regles qui en resultent en matiere de protection contre les rayonnements

    Energy Technology Data Exchange (ETDEWEB)

    Duhamel; Lavie; Fitoussi [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1958-07-01

    total irradiation will only be considered with regard to recuperation of uranium after simple machining. (author) [French] 1. L'utilisation croissante de l'energie nucleaire sous toutes ses formes a des fins pacifiques pose des problemes de securite vis-a-vis des travailleurs, des populations et des sites en general. Une etude comparee des risques d'irradiation auxquels le personnel du Commissariat a l'Energie atomique (CEA) a ete expose au cours de l'annee 1957 et des resultats du controle des radiations par les moyens de detection collectifs ou individuels montre que les installations du CEA ont une influence negligeable sur la sante, en raison de la surveillance exercee. 2. Cependant, quelques incidents de contamination et d'irradiation - sommairement indiques ainsi que la maniere dont ils ont ete regles - rendent necessaire l'elaboration d'une reglementation precise definissant les responsabilites respectives, au sein d'un etablissement nucleaire, des services utilisateurs et du Service charge de la Protection contre les Radiations, en matiere de prevention de la contamination. 3. Un ensemble coherent de regles pratiques de prevention et de protection relatives a la detention, la manipulation, le transport et le stockage de sources radioactives scellees ou non scellees, est presente. A cette fin, a partir des recommandations de la Commission Internationale de Protection Radiologique et compte tenu: - de leur nocivite radioactive; de leur activite specifique par unite de masse et du risque de contamination; les radioelements ont ete classes suivant le danger qu'ils presentent par rapport au plutonium. 4. Le Service charge de la Protection contre les Radiations intervient comme conseiller des la conception des laboratoires specialises et veille ensuite a ce que les prescriptions reglementaires de securite soient observees. 5. Des donnees elaborees, indispensables a la protection contre les rayonnements, sont mises a la

  15. Monitoring the performance of Aux. Feedwater Pump using Smart Sensing Model

    Energy Technology Data Exchange (ETDEWEB)

    No, Young Gyu; Seong, Poong Hyun [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

    2015-10-15

    Many artificial intelligence (AI) techniques equipped with learning systems have recently been proposed to monitor sensors and components in NPPs. Therefore, the objective of this study is the development of an integrity evaluation method for safety critical components such as Aux. feedwater pump, high pressure safety injection (HPSI) pump, etc. using smart sensing models based on AI techniques. In this work, the smart sensing model is developed at first to predict the performance of Aux. feedwater pump by estimating flowrate using group method of data handing (GMDH) method. If the performance prediction is achieved by this feasibility study, the smart sensing model will be applied to development of the integrity evaluation method for safety critical components. Also, the proposed algorithm for the performance prediction is verified by comparison with the simulation data of the MARS code for station blackout (SBO) events. In this study, the smart sensing model for the prediction performance of Aux. feedwater pump has been developed. In order to develop the smart sensing model, the GMDH algorithm is employed. The GMDH algorithm is the way to find a function that can well express a dependent variable from independent variables. This method uses a data structure similar to that of multiple regression models. The proposed GMDH model can accurately predict the performance of Aux.

  16. The carrier AUXIN RESISTANT (AUX1) dominates auxin flux into Arabidopsis protoplasts.

    Science.gov (United States)

    Rutschow, Heidi L; Baskin, Tobias I; Kramer, Eric M

    2014-11-01

    The ability of the plant hormone auxin to enter a cell is critical to auxin transport and signaling. Auxin can cross the cell membrane by diffusion or via auxin-specific influx carriers. There is little knowledge of the magnitudes of these fluxes in plants. Radiolabeled auxin uptake was measured in protoplasts isolated from roots of Arabidopsis thaliana. This was done for the wild-type, under treatments with additional unlabeled auxin to saturate the influx carriers, and for the influx carrier mutant auxin resistant 1 (aux1). We also used flow cytometry to quantify the relative abundance of cells expressing AUX1-YFP in the assayed population. At pH 5.7, the majority of auxin influx into protoplasts - 75% - was mediated by the influx carrier AUX1. An additional 20% was mediated by other saturable carriers. The diffusive influx of auxin was essentially negligible at pH 5.7. The influx of auxin mediated by AUX1, expressed as a membrane permeability, was 1.5 ± 0.3 μm s(-1) . This value is comparable in magnitude to estimates of efflux permeability. Thus, auxin-transporting tissues can sustain relatively high auxin efflux and yet not become depleted of auxin.

  17. Oligomerization of SCFTIR1 Is Essential for Aux/IAA Degradation and Auxin Signaling in Arabidopsis.

    Science.gov (United States)

    Dezfulian, Mohammad H; Jalili, Espanta; Roberto, Don Karl A; Moss, Britney L; Khoo, Kerry; Nemhauser, Jennifer L; Crosby, William L

    2016-09-01

    The phytohormone auxin is a key regulator of plant growth and development. Molecular studies in Arabidopsis have shown that auxin perception and signaling is mediated via TIR1/AFB-Aux/IAA co-receptors that assemble as part of the SCFTIR1/AFB E3 ubiquitin-ligase complex and direct the auxin-regulated degradation of Aux/IAA transcriptional repressors. Despite the importance of auxin signaling, little is known about the functional regulation of the TIR1/AFB receptor family. Here we show that TIR1 can oligomerize in planta via a set of spatially clustered amino acid residues. While none of the residues identified reside in the interaction interface of the TIR1-Aux/IAA degron, they nonetheless regulate the binding of TIR1 to Aux/IAA substrate proteins and their subsequent degradation in vivo as an essential aspect of auxin signaling. We propose oligomerization of TIR1 as a novel regulatory mechanism in the regulation of auxin-mediated plant patterning and development. PMID:27618443

  18. Oligomerization of SCFTIR1 Is Essential for Aux/IAA Degradation and Auxin Signaling in Arabidopsis.

    Science.gov (United States)

    Dezfulian, Mohammad H; Jalili, Espanta; Roberto, Don Karl A; Moss, Britney L; Khoo, Kerry; Nemhauser, Jennifer L; Crosby, William L

    2016-09-01

    The phytohormone auxin is a key regulator of plant growth and development. Molecular studies in Arabidopsis have shown that auxin perception and signaling is mediated via TIR1/AFB-Aux/IAA co-receptors that assemble as part of the SCFTIR1/AFB E3 ubiquitin-ligase complex and direct the auxin-regulated degradation of Aux/IAA transcriptional repressors. Despite the importance of auxin signaling, little is known about the functional regulation of the TIR1/AFB receptor family. Here we show that TIR1 can oligomerize in planta via a set of spatially clustered amino acid residues. While none of the residues identified reside in the interaction interface of the TIR1-Aux/IAA degron, they nonetheless regulate the binding of TIR1 to Aux/IAA substrate proteins and their subsequent degradation in vivo as an essential aspect of auxin signaling. We propose oligomerization of TIR1 as a novel regulatory mechanism in the regulation of auxin-mediated plant patterning and development.

  19. Création et essor de l'Institut Havrais de Sociologie économique et de Psychologie des Peuples de l'hiver 1937 aux années 1970.

    OpenAIRE

    Carbonel, Frédéric

    2006-01-01

    Article qui retrace l'essor et le rayonnement de l'Institut Havrais de Sociologie économique et de Psychologie des Peuples dont les deux principales personnalités furent les protestants André Siegfried et Abel Miroglio.

  20. Potentialités des lasers à fibre dans la génération de rayonnement cohérent UV

    Science.gov (United States)

    Martel, G.; Hideur, A.; Ortaç, B.; Lecourt, J.-B.; Chédot, C.; Brunel, M.; Chéron, B.; Limpert, J.; Tunnermann, T.; Grelu, Ph.; Gicquel-Guézo, M.; Labbé, C.; Loualiche, S.; Roussignol, Ph.; Sanchez, F.; Leblond, H.

    2006-12-01

    Le premier laser à fibre dopé aux ions de terres rares fonctionna au tout début des années 60. Il fournissait quelques milliwatts autour de 1 μm. Les décades suivantes virent très peu d'améliorations tant du côté des laboratoires que du point de vue industriel. La dernière décennie (1995/2005) vit se concrétiser la seconde révolution des lasers à fibres. Déjà kilowatt en continu, ils atteignent désormais les 1013 watts/cm2 avec des impulsions de la centaine de femtoseconde. Lors de cette présentation nous passerons en revue les potentialités des lasers à fibre. Nous décrirons les verrous technologiques qui ont été levés ces dix dernières années pour les régimes CW mais aussi femtosecondes. Nous montrerons également comment la prochaine génération de fibres optiques actuellement en développement permettra d'offrir des sources stables et de très haute puissance pour l'avenir proche.

  1. Effect of ionizing radiation on hematopoietic stem cells and progenitor cells: Role of apoptosis and potential therapeutic significance of anti-apoptotic treatments; Effet des rayonnements ionisants sur les cellules souches et progeniteurs hematopoietiques : place de l'apoptose et interet therapeutique potentiel des traitements antiapoptotiques

    Energy Technology Data Exchange (ETDEWEB)

    Drouet, M.; Mourcin, F.; Grenier, N.; Mayol, J.F.; Leroux, V. [Unite de Radiohematologie experimentale, Centre de Recherches du Service de Sante des Armees, La Tronche CEDEX (France); Sotto, J.J. [Inst. Albert Bonniot, La Tronche (France); Herodin, F. [Unite de Radiohematologie experimentale, Centre de Recherches du Service de Sante des Armees, La Tronche CEDEX (France)

    2002-07-01

    Bone marrow aplasia observed following ionizing radiation exposure (Total Body Irradiation; gamma dose range: 2-10 Gy) is a result, in particular, of the radiation-induced (RI) apoptosis in hematopoietic stem and progenitor cells (HSPC). We have previously shown in a baboon model of mobilized peripheral blood CD34{sup +} cell irradiation in vitro that RI apoptosis in HSPC was an early event, mostly occurring within the first 24 hours, which involves the CD95 Fas pathway. Apoptosis may be significantly reduced with a combination of 4 cytokines (4F): Stem Cell Factor (SCF), FLT-3 Ligand (FL), thrombopoietin (TPO), and interleukin-3 (IL-3), each at 50 ng{center_dot}mL{sup -1} (15% survival versus <3% untreated cells, 24 h post-irradiation at 2.5 Gy). In this study we show that addition of TNF-{alpha}(800 IU/ml) induces an increase in 4F efficacy in terms of cell survival 24 h after incubation (26% survival after 24 h irradiation exposure at 2.5 Gy) and amplification (k) of CD34{sup +} cells after 6 days in a serum free culture medium (SFM) (k{sub CD34{sup +}} = 4.3 and 6.3 respectively for 4F and successive 4F + TNF-{alpha}/4F treatments). In addition, the 4F combination allows culture on pre-established allogenic irradiated stromal cells in vitro at 4 Gy (k{sub CD34{sup +}} = 4.5). Overall this study suggests (i) the potential therapeutic interest for an early administration of anti-apoptotic cytokines with or without hematopoiesis inhibitors (emergency cytokine therapy) and (ii) the feasibility in the accidentally irradiated individual, of autologous cell therapy based on ex vivo expansion in order to perform autograft of residual HSPC collected after the accident. (author)

  2. Order of the 8 december 2003 fixing the modalities of implementing of the ionizing radiation protection for workers working in aircraft in flight; Arrete du 8 decembre 2003 fixant les modalites de mise en oeuvre de la protection contre les rayonnements ionisants des travailleurs affectes a l'execution de taches a bord d'aeronefs en vol

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-02-15

    This order concerns the cosmic radiation exposure for workers working in aircraft in flight. The individual exposure of any workers to an effective dose of more than 1 mSv per year, have to be evaluated. (A.L.B.)

  3. Decree no. 2003-296 on the 31 of march 2003 relative to the workers protection against the ionizing radiations; Decret no. 2003-296 du 31 mars 2003 relatif a la protection des travailleurs contre les dangers des rayonnements ionisants

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-07-01

    The different conditions modifying the Labour code in relation with the radiation protection of workers are exposed in detail, from the occupational exposure in normal conditions, the organisation of radiation protection, the abnormal working conditions until the medical examinations and medical follow up. (N.C.)

  4. Synthesis and evaluation of new organic and phosphorous derivatives against ionizing radiation: study of the in vitro mechanism of action; Synthese et evaluation de nouveaux composes organiques et phosphores contre les effets des rayonnements ionisants. Etude de leur mecanisme d'action in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Prouillac, C

    2006-10-15

    This work falls under a research program. The aim was to synthesize new organic phosphorylated compounds having an interesting radio pharmacological activity without toxicity. That is why, we carried out the synthesis of new benzothiazole and thiadiazole N-substituted derivatives as thiols, amino thiols, acids thio-sulfonic and phosphoro thioates. All these compounds were characterized by NMR (proton, carbon, phosphorus, 2D), by mass spectrometry, elementary analyzes and for some of them by diffraction of x-rays. The activity of the majority of them was evaluated by in vitro tests. The experimental results were confirmed by theoretical study: the aim of D.F.T. calculation was the study of the mechanism of capture of the free radicals by our compounds. In addition, a study of relation structure activity (Q.S.A.R.) was carried out. Our results allow us to create a model making it possible to establish structure-activity relationship. (author)

  5. Decision of the 20 april 2005 fixing the modalities of the quality control of bone densitometers devices using ionizing radiations; Decision du 20 avril 2005 fixant les modalites du controle de qualite des dispositifs d'osteodensitometrie utilisant les rayonnements ionisants

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-06-15

    This text defines the modalities of the quality control of bone densitometers devices using ionizing radiations. It precises the internal and external quality control operations to implement, the periodicity of the control, the criteria of the performances acceptability and what to do in case of non conformity. (A.L.B.)

  6. Document sheet no.3. The sanitary effects and the medical uses of the radioactivity, the radiations, the biological effects, the medical uses; Fiche documentaire no.3. Les effets sanitaires et les usages medicaux de la radioactivite, rayonnements ionisants, les effets biologiques, les usages medicaux

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    In order to inform the public the ANCLI published information sheets. This sheet no.3 deals with the sanitary effects and the medical uses of the radioactivity. It presents the radiations definitions (the internal and external irradiation, the doses levels, the absorbed doses), the biological effects (deterministic effects, random effects and chronicity effects), and the medical uses (radiotherapy and monitoring of chemotherapy). (A.L.B.)

  7. Register of legislative and regulatory dispositions relative to the radiation protection of the population and workers against the dangers of ionizing radiations; Recueil des dispositions legislatives et reglementaires concernant la protection de la population et des travailleurs contre les dangers des rayonnements ionisants

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-12-15

    This collection of legislative arrangements concerns the protection of population and workers against the risks of ionizing radiations. Each chapter is divided in two parts: a legislative part and a statutory or regulation part. We find the different chapters in relation with protection of populations, protection of workers, public health and labour laws. (N.C.)

  8. Declaration and authorization forms for the fabrication, distribution or use of radioactive sources or electric generators of ionizing radiation; Formulaires de declaration et d'autorisation de fabrication, de distribution ou d'utilisation de sources radioactives ou de generateurs electriques de rayonnements ionisants

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-01

    This document gathers all the forms to be completed when declaring or when asking for an authorization for the fabrication, retailing or use of radioactive sources or electric equipment generating ionizing radiation. These forms can concern all domains (use of sealed radioactive sources, possession and use of a particle accelerator or of radionuclides, import or export of radionuclides or of products containing radionuclides), or the use of such materials or equipment in the medical sector, or the fabrication and use in industry or research, or in user's guides for radioactive sources

  9. Priorities in radiation protection. Propositions for a better protection of persons against the danger of ionizing radiations. Report of the Vrousos commission; Priorites en radioprotection. Propositions pour une meilleure protection des personnes contre les dangers des rayonnements ionisants. Rapport de la commission Vrousos

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-03-15

    this report presents priorities for actions and recommendations on subjects such communication, information, education, and also research, monitoring of technological development, expertise or giving users more responsibility. these recommendations are given with actions propositions on field of workers radiation protection or patients protection or radioactive sources management. (N.C.)

  10. Transposition of the 97/43 EURATOM directive. Mission on procedures and standard levels of medical examinations using ionizing radiations. The radiological procedures: quality criteria and doses optimization; Transposition de la directive 97/43 Euratom. Mission sur les procedures et les niveaux de reference des examens medicaux utilisant les rayonnements ionisants. Les procedures radiologiques: criteres de qualite et optimisation des doses

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    The objective of this report concerns the optimization of radiological practices, to avoid delivering unuseful doses while ensuring an image quality necessary to the obtaining of the desired diagnosis information. (N.C.)

  11. Health and biological effects of non-ionizing radiations. Meeting of the non-ionizing radiation section of the French radiation protection society (SFRP). Meeting review; Les effets biologiques et sanitaires des rayonnements non ionisants. Journee scientifique de la section RNI de la SFRP - Compte rendu de congres

    Energy Technology Data Exchange (ETDEWEB)

    Perrin, A.; Souques, M. [Electricite de France (EDF), 75 - Paris (France)

    2011-07-15

    This document makes a review of this conference day on biological and health effects of non-ionizing radiations. The program comprised three sessions with a total of 17 presentations dealing with: 1 - NMR: biological effects and implications of Directive 2004/40 on electromagnetic fields (S. Lehericy); 2 - impact of RF frequencies from mobile telephone antennas on body homeostasis (A. Pelletier); 3 - expression of stress markers in the brain and blood of rats exposed in-utero to a Wi-Fi signal (I. Lagroye); 4 - people exposure to electromagnetic waves: the challenge of variability and the contribution of statistics to dosimetry (J. Wiart); 5 - status of knowledge about electromagnetic fields hyper-sensitivity (J.P. Marc-Vergnes); 6 - geno-toxicity of UV radiation: respective impact of UVB and UVA (T. Douki); 7 - National day of prevention and screening for skin cancers (F. Guibal); 8 - UV tan devices: status of knowledge about cancer risks (I. Tordjman, and J. Gaillot de Saintignon); 9 - In vitro study of the extremely low frequencies (ELF) effect on genes expression (J.F. Collard); 10 - modulation of brain activity during a tapping task after exposure to a 3000 {mu}T magnetic field at 60 Hz (M. Souques and A. Legros); 11 - calculation of ELF electromagnetic fields in the human body by the finite elements method (R. Scoretti); 12 - French population exposure to the 50 Hz magnetic field (I. Magne); 13 - LF and static fields, new ICNIRP recommendations: what has changed, what remains (B. Vey. Veyret); 14 - risk assessment of low energy lighting systems - DELs and CFLs (J.P. Cesarini); 15 - biological effects to the rat of a chronic exposure to high power microwaves (R. De Seze); 16 - theoretical and experimental electromagnetic compatibility approaches of active medical implants in the 10-50 Hz frequency range: the case of implantable cardiac defibrillators (J. Katrib); 17 - French physicians and electromagnetic fields (M. Souques). (J.S.)

  12. Penser aux/les limites de nos limites

    Directory of Open Access Journals (Sweden)

    Jacques Lévy

    2010-12-01

    Full Text Available Le mot « frontière » a beaucoup de succès, dans son sens propre mais plus encore comme métaphore d’une multitude de réalités qui ont à voir avec les limites, c’est-à-dire avec notre propension à découper le monde en objets séparables. Mais on constate une grande indétermination entre concept et métaphore et un usage trop facile de mélanges entre ceux-ci. Il faut donc d’abord admettre que la matérialité n’est qu’une des composantes de notre monde, mais que l’immatériel n’est pas l’irréel, le simulé ou le métaphorique. Après un détour par une théorie des limites et ses limites et une distinction entre le topographique (continu et le topologique (discontinu appliquée à l’intérieur et aux limites d’une aire, deux exemples sont développés qui visent à montrer que, si l’on trouve des frontières, ce n’est pas forcément là où on les attend et que l’appréciation juste de la place des frontières suppose la prise en compte de bien d’autres considérations que la seule limitation volontaire et brutale du franchissement d’une ligne imaginaire tracée au sol.Think about limits and the limits of our limitsThe word “boundary” has been very successful in its literal sense but even more so as a metaphor of a multitude of realities involving limits, that is, with regards to our tendency to divide the world into separable objects. However, one can observe a considerable uncertainty between the concept and the metaphor and an utilisation too easy of various mixtures of them. It becomes necessary therefore to first admit that materiality is only one of the components of our world whilst the immaterial is not unreal, simulated or metaphoric. After a detour consisting of examining a theory of limits and its limits and making the distinction between the topographic (continuous and the topologic (discontinuous applied to the interior and the limits of an area, two examples are developed which aim to

  13. Eddy covariance flux measurements of ammonia by high temperature chemical ionisation mass spectrometry

    Directory of Open Access Journals (Sweden)

    J. Sintermann

    2011-03-01

    Full Text Available A system for fast ammonia (NH3 measurements with chemical ionisation mass spectrometry (CIMS based on a commercial Proton Transfer Reaction-Mass Spectrometer (PTR-MS is presented. It uses electron transfer reaction as ionisation pathway and features a drift tube of polyetheretherketone (PEEK and silica-coated steel. Heating the instrumental inlet and the drift tube to 180 °C enabled an effective time resolution of ~1 s and made it possible to apply the instrument for eddy covariance (EC measurements. EC fluxes of NH3 were measured over two agricultural fields in Oensingen, Switzerland, following fertilisations with cattle slurry. Air was aspirated close to a sonic anemometer at a flow of 100 STP L min−1 and was directed through a 23 m long 1/2" PFA tube heated to 150 °C to an air-conditioned trailer where the gas was sub-sampled from the large bypass stream. This setup minimised damping of fast NH3 concentration changes between the sampling point and the actual measurement. High-frequency attenuation loss of the NH3 fluxes of 20 to 40% was quantified and corrected for using an empirical ogive method. The instrumental NH3 background signal showed a minor interference with H2O which was characterised in the laboratory. The resulting correction of the NH3 flux after slurry spreading was less than 1‰. The flux detection limit of the EC system was about 5 ng m−2 s−1 while the accuracy of individual flux measurements was estimated 16% for the high-flux regime during these experiments. The NH3 emissions after broad spreading of the slurry showed an initial maximum of 150 μg m−2 s−1 with a fast decline in the following hours.

  14. Nuclear and cytoplasmic signalling in the cellular response to ionising radiation

    International Nuclear Information System (INIS)

    DNA is the universal primary target for ionising radiation; however, the cellular response is highly diversified not only by differential DNA repair ability. The monitoring system for the ionising radiation-inflicted DNA damage consists of 3 apparently independently acting enzymes which are activated by DNA breaks: two protein kinases, ATM (ataxia telangiectasia mutated) and DNA-PK (DNA-dependent protein kinase) and a poly(ADP-ribose) polymerase, PARP-1. These 3 enzymes are the source of alarm signals, which affect to various extents DNA repair, progression through the cell cycle and eventually the pathway to cell death. Their functions probably are partly overlapping. On the side of DNA repair their role consists in recruiting and/or activating the repair enzymes, as well as preventing illegitimate recombination of the damaged sites. A large part of the nuclear signalling pathway, including the integrating role of TP53 has been revealed. Two main signalling pathways start at the plasma membrane: the MAPK/ERK (mitogen and extracellular signal regulated protein kinase family) 'survival pathway' and the SAPK/JNK (stress-activated protein kinase/c-Jun N-terminal kinase) 'cell death pathway'. The balance between them is likely to determine the cell's fate. An additional important 'survival pathway' starts at the insulin-like growth factor type I receptor (IGF-IR), involves phosphoinositide- 3 kinase and Akt kinase and is targeted at inactivation of the pro-apoptotic BAD protein. Interestingly, over-expression of IGF-IR almost entirely abrogates the extreme radiation sensitivity of ataxia telangiectasia cells. When DNA break rejoining is impaired, the cell is unconditionally radiation sensitive. The fate of a repair-competent cell is determined by the time factor: the cell cycle arrest should be long enough to ensure the completion of repair. Incomplete repair or misrepair may be tolerated, when generation of the death signal is prevented. So, the character and timing

  15. Ionisation differential cross section measurements for N2 at low incident energy in coplanar and non-coplanar geometries

    Science.gov (United States)

    Sakaamini, Ahmad; Amami, Sadek; Murray, Andrew James; Ning, Chuangang; Madison, Don

    2016-10-01

    Ionisation triple differential cross sections have been determined experimentally and theoretically for the neutral molecule N2 over a range of geometries from coplanar to the perpendicular plane. Data were obtained at incident electron energies ∼10 and ∼20 eV above the ionisation potential of the 3σ g, 1π u and 2σ g states, using both equal and non-equal outgoing electron energies. The data were taken with the incident electron beam in the scattering plane (ψ = 0°), at 45° to this plane and orthogonal to the plane (ψ = 90°). The set of nine measured differential cross sections at a given energy were then inter-normalised to each other. The data are compared to new calculations using various distorted wave methods, and differences between theory and experiment are discussed.

  16. Risk of cancer from occupational exposure to ionising radiation: retrospective cohort study of workers in France, the United Kingdom, and the United States (INWORKS)

    OpenAIRE

    Richardson, David B.; Cardis, Elisabeth; Daniels, Robert D; Gillies, Michael; O’Hagan, Jacqueline A; Hamra, Ghassan B.; Haylock, Richard; Laurier, Dominique; Leuraud, Klervi; MOISSONNIER, Monika; Schubauer-Berigan, Mary K.; Thierry-Chef, Isabelle; Kesminiene, Ausrele

    2015-01-01

    Study question Is protracted exposure to low doses of ionising radiation associated with an increased risk of solid cancer? Methods In this cohort study, 308 297 workers in the nuclear industry from France, the United Kingdom, and the United States with detailed monitoring data for external exposure to ionising radiation were linked to death registries. Excess relative rate per Gy of radiation dose for mortality from cancer was estimated. Follow-up encompassed 8.2 million person years. Of 66 ...

  17. Determination of percentage 235U in depleted uranium by combination of gamma spectrometry and potentiometry and comparison with thermal ionisation mass spectrometry

    International Nuclear Information System (INIS)

    A gamma ray spectrometric method has been developed for the determination of percentage 235U in the depleted uranium samples. The concentration of 235U was determined by gamma spectrometry while that of total uranium by potentiometry. The values compared well with those obtained by thermal ionisation mass spectrometry. A value of 0.614± 0.006 and 0.617 ± 005 were obtained by gamma spectrometry and thermal ionisation mass spectrometry respectively for a set of ten measurements. (author)

  18. Numerical and Experimental Investigations of the Flow Field of Ionised Gases with Applications to High-Performance Electronics and Oil Shale Gasification

    OpenAIRE

    Al-Amayreh, Malik

    2013-01-01

    This thesis investigates two new applications of flow field ionised gases. The first application involves coupled electromagnetic and aerothermodynamic phenomena in an electrical contactor chamber. I studied a new blowout technique to control the speed of the flow. With this new blowout technique, the ionised gases can be generated between the electrodes to feed the coils with current. I observed that the recovery time for the case of higher current is less than that of the following low curr...

  19. Spin-tagged electron-hydrogen scattering: new measurements of ionisation asymmetries from threshold to 500 eV

    Energy Technology Data Exchange (ETDEWEB)

    Crowe, D.M.; Guo, X.Q.; Lubell, M.S. (City Coll., New York, NY (USA). Dept. of Physics); Slevin, J. (Saint Patrick' s Coll., Maynooth (Ireland)); Eminyan, M. (Paris-7 Univ., 75 (France))

    1990-07-14

    Using beams of polarised electrons and polarised hydrogen atoms we measured the spin antiparallel-parallel ionisation asymmetry from threshold to 500eV. Our measurements are generally more precise than those of earlier studies and, more significantly, are characterised by an energy spread that is at least an order of magnitude smaller than that of the earlier work. We compare our results with several theoretical models as well as with the results from similar experiments using polarised alkali atoms. (author).

  20. Spin-tagged electron-hydrogen scattering: new measurements of ionisation asymmetries from threshold to 500 eV

    International Nuclear Information System (INIS)

    Using beams of polarised electrons and polarised hydrogen atoms we measured the spin antiparallel-parallel ionisation asymmetry from threshold to 500eV. Our measurements are generally more precise than those of earlier studies and, more significantly, are characterised by an energy spread that is at least an order of magnitude smaller than that of the earlier work. We compare our results with several theoretical models as well as with the results from similar experiments using polarised alkali atoms. (author)

  1. Characterisation of exposure to non-ionising electromagnetic fields in the Spanish INMA birth cohort: study protocol

    OpenAIRE

    Gallastegi, Mara; Guxens, Mònica; Jiménez-Zabala, Ana; Calvente, Irene; Fernández, Marta; Birks, Laura; Struchen, Benjamin; Vrijheid, Martine; Estarlich, Marisa; Fernandez, Mariana; Torrent, Maties; Ballester, Ferran; Aurrekoetxea, Juan José; Ibarluzea, Jesús; Guerra, David

    2016-01-01

    textabstractBackground: Analysis of the association between exposure to electromagnetic fields of non-ionising radiation (EMF-NIR) and health in children and adolescents is hindered by the limited availability of data, mainly due to the difficulties on the exposure assessment. This study protocol describes the methodologies used for characterising exposure of children to EMF-NIR in the INMA (INfancia y Medio Ambiente- Environment and Childhood) Project, a prospective cohort study. Methods/Des...

  2. Structural classification of Quillaja saponins by electrospray ionisation ion trap multiple-stage mass spectrometry in combination with multivariate analysis

    OpenAIRE

    Bankefors, Johan

    2006-01-01

    This thesis describes methods for structural classification of Quillaja saponins with electrospray ionisation ion trap multiple-stage mass spectrometry, in combination with multivariate analysis. The mass spectrometry method was optimised by the use of design of experiments. 47 of previously reported Quillaja saponins from the chromatographic fractions QH-A, QH-B, and QH-C have been investigated. MS1-MS3 spectra were analysed by multivariate methods such as PCA and PLS-DA. Fragmentation of sa...

  3. The formation and evolution of reconnection-driven slow-mode shocks in a partially ionised plasma

    OpenAIRE

    Hillier, Andrew; Takasao, Shinsuke; Nakamura, Naoki

    2016-01-01

    The role of slow-mode MHD shocks in magnetic reconnection is one of great importance for energy conversion and transport, but in many astrophysical plasmas the plasma is not fully ionised. In this paper, we investigate, using numerical simulations, the role of collisional coupling between a proton-electron charge-neutral fluid and a neutral hydrogen fluid for the 1D Riemann problem initiated in a constant pressure and density background state by a discontinuity in the magnetic field. This sys...

  4. Ionising energy treatment for fresh horticultural produce -mandarins and other produce, Trials 1 and 2, May-July 1987

    International Nuclear Information System (INIS)

    Two trials are described on the effect of ionising energy treatment, or irradiation, on the quality, shelf-life and composition of fresh produce, mainly at doses consistent with disinfestation treatment for quarantine purposes. Trial 1, carried out in May 1987, deals with replicated treatments of Imperial mandarins and preliminary observation treatments on a range of other produce. Trial 2 deals with replicated treatments of Ellendale mandarins and preliminary observation treatments on other produce

  5. On magnetospheric electron impact ionisation and dynamics in Titan's ram-side and polar ionosphere – a Cassini case study

    OpenAIRE

    Lewis, G. R.; Coates, A. J.; Waite Jr, J. H.; Yelle, R. V.; Cravens, T. E.; Kurth, W.S.; Canu, P.; Müller-Wodarg, I.; M. Galand; Lummerzheim, D.; Modolo, R.; J.-E. Wahlund; Agren, K.; Young, D. T.; Bertucci, C.

    2007-01-01

    International audience We present data from the sixth Cassini flyby of Titan (T5), showing that the magnetosphere of Saturn strongly interacts with the moon's ionosphere and exo-ionosphere. A simple electron ionisation model provides a reasonable agreement with the altitude structure of the ionosphere. Furthermore, we suggest that the dense and cold exo-ionosphere (from the exobase at 1430 km and outward to several Titan radii from the surface) can be explained by magnetospheric forcing an...

  6. Formation of 2-propanol in condensed molecular films of acetaldehyde following electron impact ionisation-induced proton transfer*

    Science.gov (United States)

    Borrmann, Tobias; Swiderek, Petra

    2016-06-01

    Experimental studies on thin condensed layers of acetaldehyde have previously revealed that electron exposure at an energy above the ionisation threshold leads to formation of 2-propanol. However, the mechanism of this reaction remained unclear. Therefore, a computational approach is used to explore the electron-induced reactions of acetaldehyde yielding 2-propanol. Starting from hydrogen-bonded dimers of acetaldehyde we show that the initial ionisation event triggers proton transfer between the two acetaldehyde moieties resulting in a hydrogen-bonded complex of a [OCCH3] radical and a protonated acetaldehyde cation. Given an excess energy of up to 0.75 eV and a favourable arrangement, a methyl radical released upon dissociation of the CC bond within the [OCCH3] radical can migrate to the carbonyl carbon of the protonated acetaldehyde cation. This produces a 2-propanol radical cation and CO. Neutral 2-propanol is then obtained by recombination with a second electron. A mechanism involving ionisation-driven proton transfer is thus proposed as pathway to the formation of 2-propanol during electron exposure of condensed layers of acetaldehyde.

  7. Simulation and measurements of the response of an air ionisation chamber exposed to a mixed high-energy radiation field

    International Nuclear Information System (INIS)

    CERN's radiation protection group operates a network of simple and robust ionisation chambers that are installed inside CERN's accelerator tunnels. These ionisation chambers are used for the remote reading of ambient dose rate equivalents inside the machines during beam-off periods. This Radiation Protection Monitor for dose rates due to Induced Radioactivity ('PMI', trade name: PTW, Type 34031) is a non-confined air ionisation plastic chamber which is operated under atmospheric pressure. Besides its current field of operation it is planned to extend the use of this detector in the Large Hadron Collider to measure radiation under beam operation conditions to obtain an indication of the machine performance. Until now, studies of the PMI detector have been limited to the response to photons. In order to evaluate its response to other radiation components, this chamber type was tested at CERF, the high-energy reference field facility at CERN. Six PMI detectors were installed around a copper target being irradiated by a mixed hadron beam with a momentum of 120 GeV c-1. Each of the chosen detector positions was defined by a different radiation field, varying in type and energy of the incident particles. For all positions, detailed measurements and FLUKA simulations of the detector response were performed. This paper presents the promising comparison between the measurements and simulations and analyses the influence of the different particle types on the resulting detector response. (authors)

  8. Molecular mechanisms of plant response to ionising radiation. Exploration of the glucosinolate role in the anti-oxidative response

    International Nuclear Information System (INIS)

    Terrestrial organisms are exposed to low doses of ionising radiation from natural or anthropogenic sources. The major effects of the radiations are due to DNA deterioration and water radiolysis which generates an oxidative stress by free radical production. Plants constitute good models to study the effects of ionising radiations and the search of antioxidant molecules because of their important secondary metabolism. Thus this thesis, funded by the Brittany region, characterized the physiological and molecular response of the model plant Arabidopsis thaliana to low (10 Gy) and moderate (40 Gy) doses of ionising radiation, and was therefore interested in glucosinolates, characteristic compounds of the Brassicaceae family. The global proteomic and transcriptomic studies carried out on this model revealed (1) a common response for both doses dealing with the activation of DNA repair mechanisms, cell cycle regulation and protection of cellular structures; (2) an adjustment of the energetic metabolism and an activation of secondary compounds biosynthesis (i.e. glucosinolates and flavonoids) after the 10 Gy dose; (3) an induction of enzymatic control of ROS, the regulation of cellular components recycling and of programmed cell death after the 40 Gy dose. The potential anti-oxidative role of glucosinolates was then explored. The in vitro anti-oxidative power of some glucosinolates and their derivative products were demonstrated. Their modulating effects against irradiation-induced damages were then tested in vivo by simple experimental approaches. The importance of the glucosinolate level to give a positive or negative effect was demonstrated. (author)

  9. Mapping the ionised gas around the luminous QSO HE 1029-1401: Evidence for minor merger events?

    CERN Document Server

    Husemann, B; Wisotzki, L; Jahnke, K; Kupko, D; Nugroho, D; Schramm, M

    2010-01-01

    We present VIMOS integral field spectroscopy of the brightest radio-quiet QSO on the southern sky HE 1029-1401 at a redshift of z=0.086. Standard decomposition techniques for broad-band imaging are extended to integral field data in order to deblend the QSO and host emission. We perform a tentative analysis of the stellar continuum finding a young stellar population (<100Myr) or a featureless continuum embedded in an old stellar population (10Gyr) typical for a massive elliptical galaxy. The stellar velocity dispersion of sigma_*=320\\pm90 km/s and the estimated black hole mass log(M_BH/M_sun)=8.7\\pm0.3 are consistent with the local M_BH-sigma_* relation within the errors. For the first time we map the two-dimensional ionised gas distribution and the gas velocity field around HE 1029-1401. While the stellar host morphology is purely elliptical we find a highly structured distribution of ionised gas out to 16 kpc from the QSO. The gas is highly ionised solely by the QSO radiation and has a significantly lowe...

  10. Rapid and simultaneous determination of polychlorinated biphenyls and their main metabolites (hydroxylated and methyl sulfonyl) by gas chromatography coupled to mass spectrometry: Comparison of different ionisation modes

    International Nuclear Information System (INIS)

    Graphical abstract: -- Highlights: •Simultaneous determination of PCB, OH-PCBs and MeSO2-PCBs in a single GC–MS run. •Two different ionisation modes (EI and ECNI) are studied and compared. •The analytical characterisation of both methods is satisfactory. •Better LODs are achieved using ECNI-MS as ionisation mode. •The developed methodology is successfully applied to fish liver oil. -- Abstract: Instrumental methods based on gas chromatography coupled to mass spectrometry (GC–MS) have been developed and compared using two different MS ionisation modes, electron impact (EI) and electron capture negative ionisation (ECNI), for the fast, quantitative and simultaneous determination of polychlorinated biphenyls (PCBs) and their main metabolites (hydroxylated PCBs, OH-PCBs, and methyl sulfone PCBs, MeSO2-PCBs). Parameters affecting chromatographic separation and MS detection were evaluated in order to achieve the highest selectivity and sensitivity for both operation modes. The analytical characteristics of the developed methods were studied and compared in terms of linear range, limits of detection (LODs), limits of quantification (LOQs), and instrumental precision (repeatability and intermediate precision). Both ionisation methods showed similar precision, being relative standard deviations (RSD, %) lower than 9% and 14% for repeatability and intermediate precision, respectively. However, better LODs (from 0.01 to 0.14 pg injected for the three families of congeners studied) were achieved using ECNI-MS as ionisation mode. The suitability of the developed method was demonstrated through their application to fish liver oil samples

  11. Xpg limits the expansion of haematopoietic stem and progenitor cells after ionising radiation.

    Science.gov (United States)

    Avila, Alush I; Illing, Anett; Becker, Friedrich; Maerz, Lars D; Morita, Yohei; Philipp, Melanie; Burkhalter, Martin D

    2016-07-27

    Reduced capacity of genome maintenance represents a problem for any organism, potentially causing premature death, carcinogenesis, or accelerated ageing. Strikingly though, loss of certain genome stability factors can be beneficial, especially for the maintenance of tissue stem cells of the intestine and the haematopoietic system. We therefore screened for genome stability factors negatively impacting maintenance of haematopoietic stem cells (HSC) in the context of ionising radiation (IR). We found that in vivo knock down of Xeroderma pigmentosum, complementation group G (Xpg) causes elevation of HSC numbers after IR treatment, while numbers of haematopoietic progenitors are elevated to a lesser extent. IR rapidly induces Xpg both on mRNA and on protein level. Prevention of this induction does not influence activation of the checkpoint cascade, yet attenuates late checkpoint steps such as induction of p21 and Noxa. This causes a leaky cell cycle arrest and lower levels of apoptosis, both contributing to increased colony formation and transformation rates. Xpg thus helps to adequately induce DNA damage responses after IR, thereby keeping the expansion of damaged cells under control. This represents a new function of Xpg in the response to IR, in addition to its well-characterized role in nucleotide excision repair. PMID:27137888

  12. Genomic instability in rat: Breakpoints induced by ionising radiation and interstitial telomeric-like sequences

    International Nuclear Information System (INIS)

    The Norwegian rat (Rattus norvegicus) is the most widely studied experimental species in biomedical research although little is known about its chromosomal structure. The characterisation of possible unstable regions of the karyotype of this species would contribute to the better understanding of its genomic architecture. The cytogenetic effects of ionising radiation have been widely used for the study of genomic instability, and the importance of interstitial telomeric-like sequences (ITSs) in instability of the genome has also been reported in previous studies in vertebrates. In order to describe the unstable chromosomal regions of R. norvegicus, the distribution of breakpoints induced by X-irradiation and ITSs in its karyotype were analysed in this work. For the X-irradiation analysis, 52 foetuses (from 14 irradiated rats) were studied, 4803 metaphases were analysed, and a total of 456 breakpoints induced by X-rays were detected, located in 114 chromosomal bands, with 25 of them significantly affected by X-irradiation (hot spots). For the analysis of ITSs, three foetuses (from three rats) were studied, 305 metaphases were analysed and 121 ITSs were detected, widely distributed in the karyotype of this species. Seventy-six percent of all hot spots analysed in this study were co-localised with ITSs

  13. Genotoxicity in earthworm after combined treatment of ionising radiation and mercury

    International Nuclear Information System (INIS)

    This study was performed to investigate the acute genotoxic effects of mercury and radiation on earthworms (Eisenia fetida). The levels of DNA damage and the repair kinetics in the coelomocytes of E. fetida treated with mercuric chloride (HgCl2) and ionising radiation (gamma rays) were analysed by means of the comet assay. For detection of DNA damage and repair, E. fetida was exposed to HgCl2 (0-160 mg kg-1) and irradiated with gamma rays (0-50 Gy) in vivo. The increase in DNA damage depended on the concentration of mercury or dose of radiation. The results showed that the more the oxidative stress induced by mercury and radiation the longer the repair time that was required. When a combination of HgCl2 and gamma rays was applied, the cell damage was much higher than those treated with HgCl2 or radiation alone, which indicated that the genotoxic effects were increased after the combined treatment of mercury and radiation. (authors)

  14. Low pressure cloud chamber studies. 1. Methods of analysis of ionisation distributions

    International Nuclear Information System (INIS)

    One approach to understanding the effects of radiation on matter is to study the spatial distribution of ionisations produced by the radiation. A low pressure cloud chamber has been constructed which can resolve individual ions in the tracks of low energy electrons. Droplets formed by photoelectrons and Auger electrons from characteristic aluminium x-rays have been photographed and their three dimensional coordinates reconstructed. The accuracy of these coordinates is limited mainly by diffusion in the chamber which is estimated to be (2.8 +- 1.2) nm in unit density material. This paper describes a method of computing and analysing individual electron tracks from the droplet coordinates. Track length data has been determined for each type of track and compared with other work. Inter-droplet distance histograms and Rossi 'Y' distributions have been calculated for target sizes of 5, 10 and 20 nm in unit density material. Comparisons have been made with Monte-Carlo calculations. It is hoped that these results will be of use in checking target theories of radiation action

  15. Low Dose-Rate Effects on Chromosomal Aberrations in Workers Occupationally Exposed to Ionising Radiation

    International Nuclear Information System (INIS)

    Full text: Occupational exposure to ionising radiation can be assessed by chromosomal aberrations detected in peripheral blood lymphocytes. Blood samples were collected from 47 occupationally exposed individuals (X-ray diagnostic machines and industrial gamma defectoscopy). The chromosomal aberrations were analysed from at least 500 metaphases per person and their frequencies were compared with those obtained from 110 control individuals. It has been noticed the higher frequency of chromosomal aberrations in the exposed group related to the control. The increase was analysed according to the age groups (31-40, 41-50, and 51-60), sex and duration of employment. The higher frequency of dicentrics was not directly correlated with the age or duration of employment in the exposed group. The acentric fragments were encountered with much higher frequency in the exposed group. The chromosomal aberrations induced by low dose-rate in occupationally exposed people revealed the degree of individual sensitivity and the severity of the initial damage depending on the biological-pathological conditions. (author)

  16. An isotopic analysis of ionising radiation as a source of sulphuric acid

    Directory of Open Access Journals (Sweden)

    M. B. Enghoff

    2012-06-01

    Full Text Available Sulphuric acid is an important factor in aerosol nucleation and growth. It has been shown that ions enhance the formation of sulphuric acid aerosols, but the exact mechanism has remained undetermined. Furthermore some studies have found a deficiency in the sulphuric acid budget, suggesting a missing source. In this study the production of sulphuric acid from SO2 through a number of different pathways is investigated. The production methods are standard gas phase oxidation by OH radicals produced by ozone photolysis with UV light, liquid phase oxidation by ozone, and gas phase oxidation initiated by gamma rays. The distributions of stable sulphur isotopes in the products and substrate were measured using isotope ratio mass spectrometry. All methods produced sulphate enriched in 34S and we find an enrichment factor (δ34S of 8.7 ± 0.4‰ (1 standard deviation for the UV-initiated OH reaction. Only UV light (Hg emission at 253.65 nm produced a clear non-mass-dependent excess of 33S. The pattern of isotopic enrichment produced by gamma rays is similar, but not equal, to that produced by aqueous oxidation of SO2 by ozone. This, combined with the relative yields of the experiments, suggests a mechanism in which ionising radiation may lead to hydrated ion clusters that serve as nanoreactors for S(IV to S(VI conversion.

  17. An isotope view on ionising radiation as a source of sulphuric acid

    Directory of Open Access Journals (Sweden)

    M. B. Enghoff

    2012-02-01

    Full Text Available Sulphuric acid is an important factor in aerosol nucleation and growth. It has been shown that ions enhance the formation of sulphuric acid aerosols, but the exact mechanism has remained undetermined. Furthermore some studies have found a deficiency in the sulphuric acid budget, suggesting a missing source. In this study the production of sulphuric acid from SO2 through a number of different pathways is investigated. The production methods are standard gas phase oxidation by OH radicals produced by ozone photolysis with UV light, liquid phase oxidation by ozone, and gas phase oxidation initiated by gamma rays. The distributions of stable sulphur isotopes in the products and substrate were measured using isotope ratio mass spectrometry. All methods produced sulphate enriched in 34S and we find a δ34S value of 8.7 ± 0.4‰ (1 standard deviation for the UV-initiated OH reaction. Only UV light (Hg emission at 253.65 nm produced a clear non-mass-dependent excess of 33S. The pattern of isotopic enrichment produced by gamma rays is similar, but not equal, to that produced by aqueous oxidation of SO2 by ozone. This, combined with the relative yields of the experiments, suggests a mechanism in which ionising radiation may lead to hydrated ion clusters that serve as nanoreactors for S(IV to S(VI conversion.

  18. A special ionisation chamber for quality control of diagnostic and mammography X ray equipment

    International Nuclear Information System (INIS)

    A quality control program for X ray equipment used for conventional radiography and mammography requires the constancy check of the beam qualities in terms of the half-value layers. In this work, a special double-faced parallel-plate ionisation chamber was developed with inner electrodes of different materials, in a tandem system. Its application will be in quality control programs of diagnostic and mammography X ray equipment for confirmation of half-value layers previously determined by the conventional method. Moreover, the chamber also may be utilised for measurements of air kerma values (and air kerma rates) in X radiation fields used for conventional radiography and mammography. The chamber was studied in relation to the characteristics of saturation, ion collection efficiency, polarity effects, leakage current, and short-term stability. The energy dependence in response of each of the two faces of the chamber was determined over the conventional radiography and mammography X ray ranges (unattenuated beams). The different energy responses of the two faces of the chamber allowed the formation of a tandem system useful for the constancy check of beam qualities. (author)

  19. A comparison of statistical methods for estimation of less than detectable ionising radiation exposures

    International Nuclear Information System (INIS)

    Methods were developed to estimate the ionising radiation dose below the detection level (DL) of personal monitoring devices for a case-control study of protracted radiation exposure and lung cancer. Exposure data were grouped by dosemeter type and monitoring period. Each group contained dosimetry data that were interval-censored from limitations in measurement precision and included left-censoring of observations below detection. The grouped data were fit to a three parameter hybrid-lognormal distribution by maximum likelihood estimation. Using the fitted distribution, bootstrap samples were either simulated by Monte Carlo or constructed by sampling with replacement. The resulting bootstrap sample distributions were then used to predict the missing dose values and the associated uncertainty in the estimate. Among study subjects, 1357 workers were monitored with film dosimetry. Among the 39,263 dose observations 20,416 were recorded as zero dose, indicating 52% left-censoring. The statistical methods estimated 0.31 person-Sv below the DL or ∼1% of the total collective dose for this study population. (authors)

  20. Effect of penetrating ionising radiation on the mechanical properties of pericardium

    Energy Technology Data Exchange (ETDEWEB)

    Daar, Eman, E-mail: e.daar@surrey.ac.u [Department of Physics, University of Surrey, Guildford GU2 7XH (United Kingdom); Woods, E. [Royal Free Hampstead NHS Trust, Pond Street, Hampstead, London NW3 2QG (United Kingdom); Keddie, J.L. [Department of Physics, University of Surrey, Guildford GU2 7XH (United Kingdom); Nisbet, A. [Department of Physics, University of Surrey, Guildford GU2 7XH (United Kingdom); Royal Surrey County Hospital, Guildford (United Kingdom); Bradley, D.A. [Department of Physics, University of Surrey, Guildford GU2 7XH (United Kingdom)

    2010-07-21

    The pericardium is an anistropic composite material made up of collagen and elastin fibres embedded in an amorphous matrix mainly composed of proteoglycan and hyaluronan. The collagen fibres are arranged in layers, with different directions of alignment in each layer, giving rise to interesting mechanical properties of pericardium, including the ability to undergo large deformation during performance of regular physiological functions. The present study aims to investigate the effect of penetrating photon ionising radiation on bovine pericardium tissue, being part of a study of the effect of cardiac doses received in breast radiotherapy and the possibility that this can give rise to cardiovascular complications. Irradiation doses in the range 5-80 Gy were used. To characterise the various mechanical properties [elastic modulus, stress relaxation, ultimate tensile strength (UTS) and fracture] a uniaxial tensile test method was applied. The preliminary results reflect the wide inter-sample variations that are expected in dealing with tissues, with only a weak indication of increase in the UTS of the pericardium tissue with increase in radiation dose. Such an effect has also been observed by others, with reduction in UTS at doses of 80 Gy.

  1. Complete Ionisation of the Neutral Gas in High Redshift Radio Galaxies and Quasars

    CERN Document Server

    Curran, S J

    2012-01-01

    Cool neutral gas provides the raw material for all star formation in the Universe, and yet, from a survey of the hosts of high redshift radio galaxies and quasars, we find a complete dearth of atomic (HI 21-cm) and molecular (OH, CO, HCO+ & HCN) absorption at redshifts z > 3. Upon a thorough analysis of the optical photometry, we find that all of our targets have ionising ultra-violet continuum luminosities of logL > 23 W/Hz. We therefore attribute this deficit to the traditional optical selection of targets biasing surveys towards the most ultra-violet luminous objects, where the intense radiation excites the neutral gas to the point where it cannot engage in star formation. However, this hypothesis does not explain why there is a critical luminosity, rather than a continuum where the detections gradually become fewer and fewer as the harshness of the radiation increases. We show that by placing a quasar within a galaxy of gas there is always a finite ultra-violet luminosity above which all of the gas is...

  2. Evidence for an ionised disc in the narrow-line Seyfert 1 galaxy Ark 564

    CERN Document Server

    Vaughan, S; Reeves, J; Warwick, R; Edelson, R

    1999-01-01

    We present simultaneous ASCA and RXTE observations of Ark 564, the brightest known ``narrow-line'' Seyfert 1 in the 2-10 keV band. The measured X-ray spectrum is dominated by a steep (Gamma~2.7) power-law continuum extending to at least 20 keV, with imprinted Fe K-line and -edge features and an additional ``soft excess'' below ~1.5 keV. The energy of the iron K-edge indicates the presence of highly ionised material, which we identify in terms of reflection from a strongly irradiated accretion disc. The high reflectivity of this putative disc, together with its strong intrinsic O VIII Ly-alpha and O VIII recombination emission, can also explain much of the observed soft excess flux. Furthermore, the same spectral model also provides a reasonable match to the very steep 0.1-2 keV spectrum deduced from ROSAT data. The source is much more rapidly variable than ``normal'' Seyfert 1s of comparable luminosity, increasing by a factor of ~50% in 1.6 hours, with no measurable lag between the 0.5-2 keV and 3-12 keV band...

  3. Ionisation and dissociation of cometary gaseous organic molecules by solar wind particles I: Formic Acid

    CERN Document Server

    Pilling, S; Wolff, W; Sant'Anna, M M; Barros, A L F; De Souza, G G B; De Faria, N V C; Boechat-Roberty, H M

    2006-01-01

    In order to simulate the effects of energetic charged particles present in the solar wind colliding with the cometary gaseous formic acid molecule (HCOOH), laboratory experiments have been performed. The absolute ionisation and dissociation cross sections for this molecule interacting with solar wind particles were measured employing fast electrons in the energy range of 0.5 to 2 keV and energetic protons with energies varying from 0.128 to 2 MeV. Despite the fact that both projectiles lead to a very similar fragmentation pattern, differences in the relative intensities of the fragments were observed. Formic acid survives about 4-5 times more to the proton beam than to the energetic electron collision.The minimum momentum transfer in the electron impact case was estimated to be 3-38% larger than the minimum momentum transfer observed with the equivelocity protons. The UV photodissociation rates and half-lives for HCOOH are roughly closer to the values obtained with energetic electrons. It is consequently impo...

  4. Law on protection against ionising radiation and nuclear safety in Slovenia

    International Nuclear Information System (INIS)

    The existing legislation related to nuclear and radiation safety in Slovenia was introduced in 80's. The necessity for the new law is based on the new radiation safety standards (ICRP 60) and the intention of Slovenia to harmonize the legislation with the European Union. The harmonization means adoption of the basic safety standards and other relevant directives and regulations of Euratom. The nuclear safety section of this law is based on the legally binding international conventions ratified by Slovenia. The general approach is similar to that of some members of Nuclear Energy Agency (OECD). The guidelines of the law were set by the Ministry of the Environment and Spatial Planning, Nuclear Safety Administration, and Ministry of Health. The expert group of the Ministry of Environment and Spatial Planning and the Ministry of Health together with the representatives of the users of the ionising sources and representatives of the nuclear sector, prepared the draft of the subject law. The emphasis in this paper is given to main topics and solutions related to the control of the occupationally exposed workers, radiation safety, licensing, nuclear and waste safety, and radiation protection of people and patients. (authors)

  5. 3-D model for cosmic ray planetary ionisation in the middle atmosphere

    Directory of Open Access Journals (Sweden)

    P. I. Y. Velinov

    2005-11-01

    Full Text Available A 3-D planetary model of the cosmic ray electron production rate q(h (cm-3 s-1 has been developed for the strato-mesosphere and lower thermosphere (altitude range 30-100 km with a 10-km step. The spectrum of the primary cosmic rays is modelled by an analytical expression using input data from the CREME96 model. An isotropic penetration of the cosmic rays from the upper hemisphere is assumed in the model and a spherical shape of the Earth's atmosphere is taken into account. The longitudinal effect of ionisation from cosmic rays in the mesosphere and lower thermosphere is calculated. A graphical presentation of the computational results is given for 50 and 90 km at 0°, 40°, 50° and 70° N, S latitudes and all longitudes with a step of 30°. The results of this paper provide a basis for a quantitative understanding of the energetic processes of the middle atmosphere and mechanisms affecting the thermodynamical balance of the Earth's atmosphere.

  6. Cancer mortality risk of nuclear power workers due to the exposure of ionising radiation in Germany

    Energy Technology Data Exchange (ETDEWEB)

    Fehringer, F.; Seitz, G. [Berufsgenossenschaft der Feinmechanik und Elektrotechnik, Koln (Germany); Hammer, G.P.; Blettner, M. [Johannes Gutenberg-Universitat Mainz, Institut fur Medizinische Biometrie, Epidemiologie und Informatik des Klinikums (Germany)

    2006-07-01

    A cohort study of German nuclear power workers was set up to investigate overall and cancer mortality risk related to a chronic exposure to ionising radiation of low-level dose. The German study was performed as a part of an international study carried out by the International Agency for Research on Cancer (IARC), Lyon. First results of the international study have been published recently [1]. German data are not yet included in this analysis. The German cohort consists of 4844 employees from 10 nuclear power plants. All persons who worked in these nuclear power plants in 1991 or started employment between 1991 und 1997 are included (except for employees of one plant, whose observation period started in 1992). These persons accumulated about 31,000 person years. Overall, 68 deaths were observed in the observation period between 1.1.1991-31.12.1997. Standardized mortality ratios (SMR) were computed for all causes of death, all cancers, cardiovascular diseases, external causes, and all other causes. Overall, a strong healthy worker effect was observed (SMR=0.52 [95% CI: 0.41;0.67]). No increase in total cancer mortality was seen (SMR=0.85 [95% CI: 0.53;1.30]). However, numbers are too small for stable risk estimates and further effort is under way to complete the cohort in terms of power plants and to extend the follow-up until 2005. (authors)

  7. Contamination on Lyman continuum emission at z >= 3: implication on the ionising radiation evolution

    CERN Document Server

    Vanzella, E; Cristiani, S; Nonino, M

    2010-01-01

    We investigate the possibility of contamination by lower-redshift interlopers in the measure of the ionising radiation escaping from high redshift galaxies. Taking advantage of the new ultra-deep VLT/VIMOS U-band number counts in the GOODS-S field,we calculate the expected probability of contamination by low-z interlopers as a function of the U-mag and the image spatial resolution (PSF). Assuming that ground-based observations can not resolve objects lying within a 0.5" radius of each other, then each z>=3 galaxy has a 2.1 and 3.2% chance of foreground contamination, adopting surface density U-band number counts down to 27.5 and 28.5,respectively. Those probabilities increase to 8.5 and 12.6%, assuming 1.0" radius. If applied to the estimates reported in the literature at z~3 for which a Lyman continuum has been observed directly,the probability that at least 1/3 of them are affected by foreground contamination is larger than 50%.From a Monte-Carlo simulation we estimate the median integrated contribution of ...

  8. Keeping the Universe ionised: photoheating and the high-redshift clumping factor of the intergalactic gas

    CERN Document Server

    Pawlik, Andreas H; van Scherpenzeel, Eveline

    2009-01-01

    The critical star formation rate density required to keep the intergalactic hydrogen ionised depends crucially on the average rate of recombinations in the intergalactic medium (IGM). This rate is proportional to the clumping factor C = / avg(rho_b)^2, where rho_b and avg(rho_b) are the local and cosmic mean baryon density, respectively, and the brackets indicate spatial averaging over the recombining gas in the IGM. We perform a suite of cosmological smoothed particle hydrodynamics simulations that include radiative cooling to calculate the volume-weighted clumping factor of the IGM at redshifts z >= 6. We investigate the effect of photoionisation heating by a uniform ultraviolet background and find that photoheating strongly reduces the clumping factor as the increased pressure support smoothes out small-scale density fluctuations. Even our most conservative estimate for the clumping factor, C = 6, is five times smaller than the clumping factor that is usually employed to determine the capacity of star-fo...

  9. The Vertical Structure of Warm Ionised Gas in the Milky Way

    CERN Document Server

    Gaensler, B M; Chatterjee, S; Mao, S A

    2008-01-01

    We present a new joint analysis of pulsar dispersion measures and diffuse H-alpha emission in the Milky Way, which we use to derive the density, pressure and filling factor of the thick disk component of the warm ionised medium (WIM) as a function of height above the Galactic disk. By excluding sightlines at low Galactic latitude that are contaminated by HII regions and spiral arms, we find that the exponential scale-height of free electrons in the diffuse WIM is 1830 (+120, -250) pc, a factor of two larger than has been derived in previous studies. The corresponding inconsistent scale heights for dispersion measure and emission measure imply that the vertical profiles of mass and pressure in the WIM are decoupled, and that the filling factor of WIM clouds is a geometric response to the competing environmental influences of thermal and non-thermal processes. Extrapolating the properties of the thick-disk WIM to mid-plane, we infer a volume-averaged electron density 0.014 +- 0.001 cm^-3, produced by clouds of ...

  10. A gas ionisation Direct-STIM detector for MeV ion microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Norarat, Rattanaporn, E-mail: rattanaporn@rmutl.ac.th [University of Applied Sciences (HES-SO), Haute Ecole Arc Ingénierie, Eplatures-Gris 17, CH-2300 La Chaux-de-Fonds (Switzerland); Faculty of Science and Agriculture, Rajamangala University of Technology Lanna, Chiang Rai, 57120 Chiang Rai (Thailand); Department of Physics, University of Jyväskylä, P.O. Box 35, Jyväskylä FI-40014 (Finland); Guibert, Edouard; Jeanneret, Patrick; Dellea, Mario; Jenni, Josef [University of Applied Sciences (HES-SO), Haute Ecole Arc Ingénierie, Eplatures-Gris 17, CH-2300 La Chaux-de-Fonds (Switzerland); Roux, Adrien; Stoppini, Luc [Tissue Engineering Laboratory, Campus Biotech, Chemin des Mines 9, Geneva (Switzerland); Whitlow, Harry J. [University of Applied Sciences (HES-SO), Haute Ecole Arc Ingénierie, Eplatures-Gris 17, CH-2300 La Chaux-de-Fonds (Switzerland)

    2015-04-01

    Direct-Scanning Transmission Ion Microscopy (Direct-STIM) is a powerful technique that yields structural information in sub-cellular whole cell imaging. Usually, a Si p-i-n diode is used in Direct-STIM measurements as a detector. In order to overcome the detrimental effects of radiation damage which appears as a broadening in the energy resolution, we have developed a gas ionisation detector for use with a focused ion beam. The design is based on the ETH Frisch grid-less off-axis Geiger–Müller geometry. It is developed for use in a MeV ion microscope with a standard Oxford Microbeams triplet lens and scanning system. The design has a large available solid angle for other detectors (e.g. proton induced fluorescence). Here we report the performance for imaging ReNcells VM with μm resolution where energy resolutions of <24 keV fwhm could be achieved for 1 MeV protons using isobutane gas.

  11. Genomic instability in rat: Breakpoints induced by ionising radiation and interstitial telomeric-like sequences

    Energy Technology Data Exchange (ETDEWEB)

    Camats, Nuria [Institut de Biotecnologia i Biomedicina (IBB), Universitat Autonoma de Barcelona, 08193 Barcelona (Spain); Departament de Biologia Cel.lular, Fisiologia i Immunologia Universitat Autonoma de Barcelona, 08193 Barcelona (Spain); Ruiz-Herrera, Aurora [Departament de Biologia Cel.lular, Fisiologia i Immunologia Universitat Autonoma de Barcelona, 08193 Barcelona (Spain); Parrilla, Juan Jose [Servicio de Ginecologia y Obstetricia, Hospital Universitario Virgen de la Arrixaca, Ctra, Madrid-Cartagena, s/n, El Palmar, 30120 Murcia (Spain); Acien, Maribel [Servicio de Ginecologia y Obstetricia, Hospital Universitario Virgen de la Arrixaca, Ctra, Madrid-Cartagena, s/n, El Palmar, 30120 Murcia (Spain); Paya, Pilar [Servicio de Ginecologia y Obstetricia, Hospital Universitario Virgen de la Arrixaca, Ctra, Madrid-Cartagena, s/n, El Palmar, 30120 Murcia (Spain); Giulotto, Elena [Dipartimento di Genetica e Microbiologia Adriano Buzzati Traverso, Universita degli Studi di Pavia, 27100 Pavia (Italy); Egozcue, Josep [Departament de Biologia Cel.lular, Fisiologia i Immunologia Universitat Autonoma de Barcelona, 08193 Barcelona (Spain); Garcia, Francisca [Institut de Biotecnologia i Biomedicina (IBB), Universitat Autonoma de Barcelona, 08193 Barcelona (Spain); Garcia, Montserrat [Institut de Biotecnologia i Biomedicina (IBB), Universitat Autonoma de Barcelona, 08193 Barcelona (Spain) and Departament de Biologia Cellular, Fisiologia i Immunologia Universitat Autonoma de Barcelona, 08193 Barcelona (Spain)]. E-mail: Montserrat.Garcia.Caldes@uab.es

    2006-03-20

    The Norwegian rat (Rattus norvegicus) is the most widely studied experimental species in biomedical research although little is known about its chromosomal structure. The characterisation of possible unstable regions of the karyotype of this species would contribute to the better understanding of its genomic architecture. The cytogenetic effects of ionising radiation have been widely used for the study of genomic instability, and the importance of interstitial telomeric-like sequences (ITSs) in instability of the genome has also been reported in previous studies in vertebrates. In order to describe the unstable chromosomal regions of R. norvegicus, the distribution of breakpoints induced by X-irradiation and ITSs in its karyotype were analysed in this work. For the X-irradiation analysis, 52 foetuses (from 14 irradiated rats) were studied, 4803 metaphases were analysed, and a total of 456 breakpoints induced by X-rays were detected, located in 114 chromosomal bands, with 25 of them significantly affected by X-irradiation (hot spots). For the analysis of ITSs, three foetuses (from three rats) were studied, 305 metaphases were analysed and 121 ITSs were detected, widely distributed in the karyotype of this species. Seventy-six percent of all hot spots analysed in this study were co-localised with ITSs.

  12. Application of real-time RT-PCR quantification to evaluate differential expres sion of Arabidopsis Aux/IAAgenes

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The molecular techniques including Northern blot, dot blot, in situ hybridization, etc. have been success fully used to estimate semi-quantitatively mRNA levels in plant samples. In this study, we employed a real-time reverse transcription-PCR (RT-PCR) assay using SYBR Green Ifluorescence methodology to evaluate accurate quant itation and sequence specific detection of Aux/IAA mRNA levels in Arabidopsis. Results obtained indicate a linear dynamic range of 102-106 Aux/IAA mRNA copies with standard de viations of generally less than 15%. As a model experiment,the outcome of analysis of expression patterns of five Aux/IAA genes in Arabidopsis under various chemical and temperature treatments is presented. The method presented here provides a sensitive and rapid technique to evaluate plant Aux/IAA mRNA expression levels in nanogram order.

  13. Le Carnaval de Schignano : un dernier salut aux émigrants

    Directory of Open Access Journals (Sweden)

    Cristina Del Biaggio

    2011-05-01

    Full Text Available Pour arriver à Schignano, il faut passer par una cürva al giazz e una cürva al suu [Un virage dans la glace et un virage au soleil], comme disent les mots en dialecte d’une récente chanson écrite par Davide Van De Sfroos, compositeur-interprète de la région. C’est dans ce petit hameau de la Vallée d’Intelvi, au-dessus du Lac de Côme, que, tous les ans, le carnaval anime le village. Une fête populaire spontanée, sans règles écrites, ni lois, qui survit grâce aux habitants qui l’animent, aux ar...

  14. Disruptions in AUX1-Dependent Auxin Influx Alter Hypocotyl Phototropism in Arabidopsis

    Institute of Scientific and Technical Information of China (English)

    Bethany B.Stone; Emily L.Stowe-Evans; Reneé M.Harper; R.Brandon Celaya; Karin Ljung; G(o)ran Sandberg; Emmanuel Liscum

    2008-01-01

    Phototropism represents a differential growth response by which plant organs can respond adaptively to changes in the direction of incident light to optimize leaf/stem positioning for photosynthetic light capture and root growth orientation for water/nutrient acquisition. Studies over the past few years have identified a number of components in the signaling pathway(s) leading to development of phototropic curvatures in hypocotyls. These include the phototropin photoreceptors (phot1 and phot2) that perceive directional blue-light (BL) cues and then stimulate signaling,leading to relocalization of the plant hormone auxin, as well as the auxin response factor NPH4/ARF7 that responds to changes in local auxin concentrations to directly mediate expression of genes likely encoding proteins necessary for development of phototropic curvatures. While null mutations in NPH4/ARF7 condition an aphototropic response to unidirectional BL, seedlings carrying the same mutations recover BL-dependent phototropic responsiveness if coirradiated with red light (RL) or pre-treated with either ethylene. In the present study, we identify second-site enhancer mutations in the nph4 background that abrogate these recovery responses. One of these mutations-map1 ((m)odifier of (a)rf7 (p)henotypes (1))-was found to represent a missense allele of AUX1-a gene encoding a high-affinity auxin influx carrier previously associated with a number of root responses. Pharmocological studies and analyses of additional aux1 mutants confirmed that AUX1 functions as a modulator of hypocotyl phototropism. Moreover, we have found that the strength of dependence of hypocotyl phototropism on AUX1-mediated auxin influx is directly related to the auxin responsiveness of the seedling in question.

  15. Report of transparency and nuclear safety 2007 CEA Fontenay aux Roses

    International Nuclear Information System (INIS)

    This report presents the activities of the CEA Center of Fontenay aux roses for the year 2007. After many years of decommissioning and dismantling of nuclear installations, the Center is now devoted (since 2005) to the development of research programmes on biology and biomedical technologies. The actions concerning the safety, the radiation protection, the significant events, the release control and the environmental impacts and the wastes stored on the center are discussed. (A.L.B.)

  16. T0002 / MilliNewton / Erreurs dues à l'orientation et aux forces latérales

    OpenAIRE

    Maeder, Thomas

    2004-01-01

    Le capteur de force MilliNewton est sensible aux forces latérales, dans le sens longitudinal à la poutre. Le degré de sensibilité du capteur à ces forces dépend essentiellement de la taille de la bille et de la longueur de la poutre. En revanche, la sensibilité aux forces latérales perpendiculaires à la poutre est très faible.

  17. Phenolic compounds from red wine are protective against the DNA damaging effect of ionising radiation ex vivo

    International Nuclear Information System (INIS)

    Full text: Using the cytokinesis-block micronucleus assay we (a) investigated which compounds in red wine can prevent oxidative damage to DNA in vitro and (b) performed in vivo interventions with red wine (RW), de-alcoholised red wine (DEALC) and alcohol (ALC) to distinguish the effects of alcohol from the other fractions of RW in prevention of oxidative damage to DNA ex vivo. Cells were either challenged with ionising gamma radiation or hydrogen peroxide, two different forms of oxidative stress. The relative contribution of ethanol, glycerol, tartaric acid, catechin + caffeic acid, a mixture of all of these and phenolic stripped RW at in vivo relevant concentrations on spontaneous and oxidative stress induced DNA damage was evaluated in vitro. The results from these studies have shown that (a) only ethanol significantly increases spontaneous DNA damage, but this effect is eliminated when ethanol is included in a mixture of all the other wine components (P<0.05), (b) the strongest and only significant protective effect against hydrogen peroxide induced DNA damage was observed for the catechin + caffeic acid mixture (P<0.05) and (c) all compounds tested were significantly protective against ionising radiation-induced DNA damage in a dose dependent manner with the strongest protection being observed for the catechin + caffeic acid mixture and a mixture of all components (P < 0.0001). In the in vivo intervention studies with ex vivo challenge of whole blood showed that 1-2h after consumption of 300ml DEALC produced a significant protection against the DNA damaging effects of ionising radiation (P = 0.0002) but ALC significantly enhanced the damaging effects of ionising radiation (P 0.0002) while RW produced an intermediate effect. The data from these studies are particularly interesting because they clearly demonstrate the potential beneficial effects of wine phenolics in counteracting the harmful effects of ionising radiation. Furthermore they demonstrate that the

  18. The Design of Diagnostic Medical Facilities where Ionising Radiation is used

    International Nuclear Information System (INIS)

    The original Code of Practice on The Design of Diagnostic Medical Facilities Using Ionising Radiation was first published by the Nuclear Energy Board in 1988. In the intervening years the 'Blue Book' as it became known has served the medical community well as the sector has expanded and modernised and the late Dr Noel Nowlan, then Chief Executive of the Nuclear Energy Board, deserves much credit for initiating this pioneering contribution to radiation safety in Ireland. There have been significant developments since its publication in terms of the underlying radiation protection legislation, regulatory practice as well as developments in new technologies that have given rise to the need for a revision of the Code. This revised Code is based on a comprehensive draft document produced by the Haughton Institute under contract to the RPII and was finalised following extensive consultations with the relevant stakeholders. The revised Code includes a brief review of the current legislative framework and its specific impact on the management of building projects (Chapters 1 and 2), a presentation of the main types of radiological (Chapter 3) and nuclear medicine (Chapter 4) facilities, a treatment of the technical aspects of shielding calculations (Chapter 5) and a discussion of the practical aspects of implementing shielding solutions in a building context (Chapter 6). The primary purpose of the Code is to assist in the design of diagnostic facilities to the highest radiation protection standards in order to ensure the safety of workers and members of the public and the delivery of a safe service to patients. Diagnostic radiology is a dynamic environment and the Code is intended to be used in consultation with the current literature, an experienced Radiation Protection Advisor and a multidisciplinary project team

  19. The Follow-Up of Persons Occupationally Overexposed to Ionising Radiations

    International Nuclear Information System (INIS)

    The number of occasions on which workers are overexposed to ionising radiations is very small even when the definition of an overexposure is taken as being any amount in excess of an ICRP permissible level. There is a need for the fullest information about the prognostic significance of overexposures to be. obtained. While it is true that much larger radiation doses are incurred in therapy, or even in some X-ray diagnostic procedures, there are other factors, such as underlying diseases, which can complicate the interpretation of biological consequences in these cases. Therefore, a simple system of registration for all overexposures to workers should be introduced. Such a system should cover only the relatively small number of cases either of external radiation or of internal contamination in which the dose can be considered likely to be in any way significant in respect of ultimate prognosis. Any necessary administrative effort should be made available by a critical review of the effort devoted to the routine recording of very low doses. This paper outlines an example of a registration system which has been instituted in the United Kingdom and outlines the reasoning behind the limited amount of recording which is considered to be useful. In addition to statistical studies of overexposures, there is a need to apply sound occupational health principles to the supervision and future employment of workers involved in such incidents. These should reflect an individual assessment of all aspects of such cases and rule of thumb numerical rules should not apply. Relevant factors in these individual assessments are discussed. (author)

  20. Positive effects of small doses of ionising radiation on plants and animals

    International Nuclear Information System (INIS)

    Although part of the favourable results is likely to be due to wrong methods there is still a big part which must be taken seriously. Positive effects occurred after irradiation with X-, β, and γ rays and fast electrons. In plants, positive effects occurred after acute irradiation of the seed in the range of 1 R-10000 R, after acute irradiation of the growing plants with 50 R-1000, and after chronic irradiation of growing plants in the range of 0.02 R/day-230 R/day. For insects, the radiation doses with stimulating effects were, for acute irradiation, between 50 R and 180.00O R, for chronic irradiation between 9.5 R/day-75.9 R/hour. For mammals, positive effects of acute irradiation were found in the range of 40 R-400 R, after chronic irradiation of 0.11 R/day-5 R/day. The lower limits of these dose ranges are mainly due to the fact that smaller doses have not been dealt with at all. Positive effects of ionising radiation were seen especially when the experimental animals or plants were kept under unfavourable conditions. The exact mechanism of the radiation stimulation has not been explained yet. The assumption is favoured that the radiation causes a stimulation of repair mechanisms, - similar to the enzyme induction, may be - which enables the organisms to face further damage better due to their improved repair capacity. The generation of heterocygotes or of polyploidy by radiation seems also a plausible explanation of the positive radiation effects. In some experiments which revealed an increased radiation resistance after pre-radiation the synchronisation of the cell cycle caused by a radiation-induced delay of unitosis is likely to play a role. (orig./MG)

  1. Transfert de rayonnement hors ETL pour l'étude des photosphères et des chromosphères stellaires : applications aux atomes du magnésium, du calcium et du fer dans les étoiles tardives.

    OpenAIRE

    Merle, Thibault

    2012-01-01

    The stellar abundance analysis frequently relies on the local thermodynamic equilibrium (LTE) assumption for spectral line formation. This assumption is not always appropriate, in particular, for metal-poor and/or evolved stars. To better understand these stars and contrain their impacts in the chemical enrichment of the Galaxy, it is necessary to use a non-LTE (NLTE) description more realistic but also more complex to built up. My thesis work consisted in constructing model atoms from the mo...

  2. The electrical charging of inactive aerosols in high ionised atmosphere, the electrical charging of artificial beta radioactive aerosols; Le processus de charge electrique: des aerosols non radioactifs en milieu fortement ionise, des aerosols radioactifs artificiels emetteurs beta

    Energy Technology Data Exchange (ETDEWEB)

    Gensdarmes, F

    2000-07-01

    The electrical properties of aerosols greatly influence their transport and deposition in a containment. In a bipolar ionic atmosphere, a neutral electric charge on aerosols is commonly assumed. However, many studies report a different charge distribution in some situations, like highly ionised atmosphere or in the case of radioactive aerosols. Such situations could arise from a hypothetical accident in a nuclear power plant. Within the framework of safety studies which are carried out at IPSN, our aims were the study of electrical properties of aerosols in highly ionised atmosphere, and the study of artificial radioactive aerosols, in order to suggest experimental validation of available theories. For this purpose, we designed an experimental device that allows us to measure non-radioactive aerosol charge distribution under high gamma irradiation, up to 10{sup 4} Gy/h. With our experimental device we also studied the properties of small ions in the medium. Our results show a variation of the charge distribution in highly ionised atmosphere. The charge increases with the dose of gamma ray. We have related this variation with the one of the small ions in the gases, according to theoretical prediction. However, the model overestimates slightly our experimental results. In the case of the radioactive aerosols, we have designed an original experimental device, which allows us to study the charge distribution of a {sup 137}Cs aerosol. Our results show that the electric charging of such aerosols is strongly dependent on evolution parameters in a containment. So, our results underline a great enhancement of self-charging of particles which are sampled in a confined medium. Our results are qualitatively in agreement with the theoretical model; nevertheless the latter underestimates appreciably the self-charging, owing to the fact that wall effects are not taken into account. (author)

  3. Applications of electron spin resonance to some problems of radiation chemistry; Applications de la resonance paramagnetique electronique a quelques problemes de chimie sous rayonnements

    Energy Technology Data Exchange (ETDEWEB)

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

    1968-06-01

    The electron spin resonance (E.S.R.) spectra of gamma irradiated polar organic glasses, at 77 K, shows a single line centered at g {approx} 2, attributed to solvated electrons. The radicals produced on scavenging this species by electron acceptors, such as aromatic hydrocarbons, nitro-compounds and azines have been studied by E.S.R. In most cases, the radicals from these solutes, the spectra of which are observed after elimination by warming of the radicals from the matrices, are produced by protonation of the anions formed by scavenging of electrons at 77 K. Thus, in the case of glassy solutions of nitro-compounds, the radicals R NO{sub 2}H are formed. They are characterized by a{sub N} = 15 G (nitrobenzene) or a{sub N} = 28 G (nitro-alkane). These radicals are also generated by U.V, photolysis at room temperature of solutions of nitro-compounds in alcohols and are shown to be the precursors of nitroxide radicals R - N - R (with N - O) observed simultaneously. Gamma irradiation of solutions of pyridine and of the three diazines, in alcohol glasses at 77 K, produces the radical formed by hydrogen addition to these compounds. The value of the coupling constant of the additional proton (7-10 G) indicates that it is bound to a nitrogen in the sp{sup 2} hydridation state. One has shown, taking pyridine as an example, that the addition to a carbon gives a much greater value of the coupling constant, of the order of 50-60 G. (author) [French] Les spectres de resonance paramagnetique electronique (R.P.E.) obtenus apres irradiation gamma, a 77 K, de verres organiques polaires tels que les alcools, comportent une bande unique centree a g {approx} 2, attribuable aux electrons solvates. On etudie par R.P.E. les radicaux provenant de leur capture par des solutes ayant une affinite electronique, en particulier les hydrocarbures aromatiques, les composes nitres et les azines. En general, les radicaux provenant de ces solutes, dont on observe les spectres apres elimination

  4. The ARF, AUX/IAA and GH3 gene families in citrus: genome-wide identification and expression analysis during fruitlet drop from abscission zone A.

    Science.gov (United States)

    Xie, Rangjin; Pang, Shaoping; Ma, Yanyan; Deng, Lie; He, Shaolan; Yi, Shilai; Lv, Qiang; Zheng, Yongqiang

    2015-12-01

    Completion of the whole genome sequencing of citrus enabled us to perform genome-wide identification and functional analysis of the gene families involved in agronomic traits and morphological diversity of citrus. In this study, 22 CitARF, 11 CitGH3 and 26 CitAUX/IAA genes were identified in citrus, respectively. Phylogenetic analysis revealed that all the genes of each gene family could be subdivided into three groups and showed strong evolutionary conservation. The GH3 and AUX/IAA gene families shrank and ARF gene family was highly conserved in the citrus genome after speciation from Arabidopsis thaliana. Tissue-specific expression profiles revealed that 54 genes were expressed in at least one tissue while just 5 genes including CitARF07, CitARF20, CitGH3.04, CitAUX/IAA25 and CitAUX/IAA26 with very low expression level in all tissues tested, suggesting that the CitARF, CitGH3 and CitAUX/IAA gene families played important roles in the development of citrus organs. In addition, our data found that the expression of 2 CitARF, 4 CitGH3 and 4 AUX/IAA genes was affected by IAA treatment, and 7 genes including, CitGH3.04, CitGH3.07, CitAUX/IAA03, CitAUX/IAA04, CitAUX/IAA18, CitAUX/IAA19 and CitAUX/IAA23 were related to fruitlet abscission. This study provides a foundation for future studies on elucidating the precise role of citrus ARF, GH3 and AUX/IAA genes in early steps of auxin signal transduction and open up a new opportunity to uncover the molecular mechanism underlying citrus fruitlet abscission.

  5. The ARF, AUX/IAA and GH3 gene families in citrus: genome-wide identification and expression analysis during fruitlet drop from abscission zone A.

    Science.gov (United States)

    Xie, Rangjin; Pang, Shaoping; Ma, Yanyan; Deng, Lie; He, Shaolan; Yi, Shilai; Lv, Qiang; Zheng, Yongqiang

    2015-12-01

    Completion of the whole genome sequencing of citrus enabled us to perform genome-wide identification and functional analysis of the gene families involved in agronomic traits and morphological diversity of citrus. In this study, 22 CitARF, 11 CitGH3 and 26 CitAUX/IAA genes were identified in citrus, respectively. Phylogenetic analysis revealed that all the genes of each gene family could be subdivided into three groups and showed strong evolutionary conservation. The GH3 and AUX/IAA gene families shrank and ARF gene family was highly conserved in the citrus genome after speciation from Arabidopsis thaliana. Tissue-specific expression profiles revealed that 54 genes were expressed in at least one tissue while just 5 genes including CitARF07, CitARF20, CitGH3.04, CitAUX/IAA25 and CitAUX/IAA26 with very low expression level in all tissues tested, suggesting that the CitARF, CitGH3 and CitAUX/IAA gene families played important roles in the development of citrus organs. In addition, our data found that the expression of 2 CitARF, 4 CitGH3 and 4 AUX/IAA genes was affected by IAA treatment, and 7 genes including, CitGH3.04, CitGH3.07, CitAUX/IAA03, CitAUX/IAA04, CitAUX/IAA18, CitAUX/IAA19 and CitAUX/IAA23 were related to fruitlet abscission. This study provides a foundation for future studies on elucidating the precise role of citrus ARF, GH3 and AUX/IAA genes in early steps of auxin signal transduction and open up a new opportunity to uncover the molecular mechanism underlying citrus fruitlet abscission. PMID:25982744

  6. Lightning-driven inner radiation belt energy deposition into the atmosphere: implications for ionisation-levels and neutral chemistry

    Directory of Open Access Journals (Sweden)

    C. J. Rodger

    2007-08-01

    Full Text Available Lightning-generated whistlers lead to coupling between the troposphere, the Van Allen radiation belts and the lower-ionosphere through Whistler-induced electron precipitation (WEP. Lightning produced whistlers interact with cyclotron resonant radiation belt electrons, leading to pitch-angle scattering into the bounce loss cone and precipitation into the atmosphere. Here we consider the relative significance of WEP to the lower ionosphere and atmosphere by contrasting WEP produced ionisation rate changes with those from Galactic Cosmic Radiation (GCR and solar photoionisation. During the day, WEP is never a significant source of ionisation in the lower ionosphere for any location or altitude. At nighttime, GCR is more significant than WEP at altitudes <68 km for all locations, above which WEP starts to dominate in North America and Central Europe. Between 75 and 80 km altitude WEP becomes more significant than GCR for the majority of spatial locations at which WEP deposits energy. The size of the regions in which WEP is the most important nighttime ionisation source peaks at ~80 km, depending on the relative contributions of WEP and nighttime solar Lyman-α. We also used the Sodankylä Ion Chemistry (SIC model to consider the atmospheric consequences of WEP, focusing on a case-study period. Previous studies have also shown that energetic particle precipitation can lead to large-scale changes in the chemical makeup of the neutral atmosphere by enhancing minor chemical species that play a key role in the ozone balance of the middle atmosphere. However, SIC modelling indicates that the neutral atmospheric changes driven by WEP are insignificant due to the short timescale of the WEP bursts. Overall we find that WEP is a significant energy input into some parts of the lower ionosphere, depending on the latitude/longitude and altitude, but does not play a significant role in the neutral chemistry of the mesosphere.

  7. Lightning-driven inner radiation belt energy deposition into the atmosphere: implications for ionisation-levels and neutral chemistry

    Science.gov (United States)

    Rodger, C. J.; Enell, C.-F.; Turunen, E.; Clilverd, M. A.; Thomson, N. R.; Verronen, P. T.

    2007-08-01

    Lightning-generated whistlers lead to coupling between the troposphere, the Van Allen radiation belts and the lower-ionosphere through Whistler-induced electron precipitation (WEP). Lightning produced whistlers interact with cyclotron resonant radiation belt electrons, leading to pitch-angle scattering into the bounce loss cone and precipitation into the atmosphere. Here we consider the relative significance of WEP to the lower ionosphere and atmosphere by contrasting WEP produced ionisation rate changes with those from Galactic Cosmic Radiation (GCR) and solar photoionisation. During the day, WEP is never a significant source of ionisation in the lower ionosphere for any location or altitude. At nighttime, GCR is more significant than WEP at altitudes WEP starts to dominate in North America and Central Europe. Between 75 and 80 km altitude WEP becomes more significant than GCR for the majority of spatial locations at which WEP deposits energy. The size of the regions in which WEP is the most important nighttime ionisation source peaks at ~80 km, depending on the relative contributions of WEP and nighttime solar Lyman-α. We also used the Sodankylä Ion Chemistry (SIC) model to consider the atmospheric consequences of WEP, focusing on a case-study period. Previous studies have also shown that energetic particle precipitation can lead to large-scale changes in the chemical makeup of the neutral atmosphere by enhancing minor chemical species that play a key role in the ozone balance of the middle atmosphere. However, SIC modelling indicates that the neutral atmospheric changes driven by WEP are insignificant due to the short timescale of the WEP bursts. Overall we find that WEP is a significant energy input into some parts of the lower ionosphere, depending on the latitude/longitude and altitude, but does not play a significant role in the neutral chemistry of the mesosphere.

  8. Use of the Isomass 54E thermal ionisation mass spectrometer at AEE Winfrith. Part II: plutonium analysis

    International Nuclear Information System (INIS)

    This report describes the application of the Isomass 54E Thermal ionisation mass spectrometer for the isotopic analysis of plutonium, and gives details of the development of a method for quantitative determination of plutonium in sample solutions using isotopic dilution. A computer program for the control of the 54E is also described. Isotope dilution was used to compare results of plutonium content of twelve zebra reactor fuel pellets with results obtained by titrimetry. The Isomass 54E is shown to be capable of high precision analysis of plutonium sample solutions for both isotopic content and total plutonium concentration using an isotope dilution technique. (U.K.)

  9. Current status of matrix-assisted laser desorption ionisation-time of flight mass spectrometry in the clinical microbiology laboratory.

    Science.gov (United States)

    Kok, Jen; Chen, Sharon C A; Dwyer, Dominic E; Iredell, Jonathan R

    2013-01-01

    The integration of matrix-assisted laser desorption ionisation-time of flight mass spectrometry (MALDI-TOF MS) into many clinical microbiology laboratories has revolutionised routine pathogen identification. MALDI-TOF MS complements and has good potential to replace existing phenotypic identification methods. Results are available in a more clinically relevant timeframe, particularly in bacteraemic septic shock. Novel applications include strain typing and the detection of antimicrobial resistance, but these are not widely used. This review discusses the technical aspects, current applications, and limitations of MALDI-TOF MS.

  10. Predicting the effects of ionising radiation on ecosystems by a generic model based on the Lotka-Volterra equations.

    Science.gov (United States)

    Monte, Luigi

    2009-06-01

    The present work describes a model for predicting the population dynamics of the main components (resources and consumers) of terrestrial ecosystems exposed to ionising radiation. The ecosystem is modelled by the Lotka-Volterra equations with consumer competition. Linear dose-response relationships without threshold are assumed to relate the values of the model parameters to the dose rates. The model accounts for the migration of consumers from areas characterised by different levels of radionuclide contamination. The criteria to select the model parameter values are motivated by accounting for the results of the empirical studies of past decades. Examples of predictions for long-term chronic exposure are reported and discussed.

  11. Predicting the effects of ionising radiation on ecosystems by a generic model based on the Lotka-Volterra equations

    Energy Technology Data Exchange (ETDEWEB)

    Monte, Luigi [ENEA CR Casaccia, Via P. Anguillarese 301 00100 Rome (Italy)], E-mail: luigi.monte@enea.it

    2009-06-15

    The present work describes a model for predicting the population dynamics of the main components (resources and consumers) of terrestrial ecosystems exposed to ionising radiation. The ecosystem is modelled by the Lotka-Volterra equations with consumer competition. Linear dose-response relationships without threshold are assumed to relate the values of the model parameters to the dose rates. The model accounts for the migration of consumers from areas characterised by different levels of radionuclide contamination. The criteria to select the model parameter values are motivated by accounting for the results of the empirical studies of past decades. Examples of predictions for long-term chronic exposure are reported and discussed.

  12. Simulation of ultra thin film SOI transistors using a non-local ballistic model for impact ionisation

    Science.gov (United States)

    Armstrong, G. A.; French, W. D.

    1992-12-01

    To model bipolar snapback in thin film SOI transistors accurately, it is necessary to employ a non-local model of impact ionisation. Such a model, based on the "Lucky electron" theory, has been incorporated in a two-dimensional device simulator. Accurate prediction of bipolar holding voltage has been obtained for SOI transistors with sub-micron gate lengths. The model has been applied to analyse separately the effects of both lightly doped source and lightly doped drain in maximising the holding voltage. The advantage of using ultra thin highly doped SOI films in conjunction with a lightly doped drain is discussed.

  13. The ENEA calibration service for ionising radiations; Il centro di taratura per le radiazioni ionizzanti di Bologna. Parte 1: Fotoni

    Energy Technology Data Exchange (ETDEWEB)

    Monteventi, F.; Sermenghi, I. [ENEA, Centro Ricerche Ezio Clementel, Bologna (Italy). Dipt. Ambiente

    1999-07-01

    The report describes all the facilities available at the the service of the ENEA Calibration Service for Ionising Radiations at Bologna (Italy). It gives a detailed description of all equipment qualified for photon fields metrology including the secondary standards and the calibration procedures performed for radiation monitoring devices and dosemeters. [Italian] Il presente lavoro descrive i servizi e le attivita' del Centro di Taratura dell'ENEA di Bologna, in particolare delle attrezzature qualificate per la metrologia fotonica, dei campioni di misura e delle procedure adottate per la taratura degli strumenti e dei dosimetri.

  14. Chemical composition and geologic history of saline waters in Aux Vases and Cypress Formations, Illinois Basin

    Science.gov (United States)

    Demir, I.; Seyler, B.

    1999-01-01

    Seventy-six samples of formation waters were collected from oil wells producing from the Aux Vases or Cypress Formations in the Illinois Basin. Forty core samples of the reservoir rocks were also collected from the two formations. Analyses of the samples indicated that the total dissolved solids content (TDS) of the waters ranged from 43,300 to 151,400 mg/L, far exceeding the 35,400 mg/mL of TDS found in typical seawater. Cl-Br relations suggested that high salinities in the Aux Vases and Cypress formation waters resulted from the evaporation of original seawater and subsequent mixing of the evaporated seawater with concentrated halite solutions. Mixing with the halite solutions increased Na and Cl concentrations and diluted the concentration of other ions in the formation waters. The elemental concentrations were influenced further by diagenetic reactions with silicate and carbonate minerals. Diagenetic signatures revealed by fluid chemistry and rock mineralogy delineated the water-rock interactions that took place in the Aux Vases and Cypress sandstones. Dissolution of K-feldspar released K into the solution, leading to the formation of authigenic illite and mixed-layered illite/smectite. Some Mg was removed from the solution by the formation of authigenic chlorite and dolomite. Dolomitization, calcite recrystallization, and contribution from clay minerals raised Sr levels significantly in the formation waters. The trend of increasing TDS of the saline formation waters with depth can be explained with density stratification. But, it is difficult to explain the combination of the increasing TDS and increasing Ca/Na ratio with depth without invoking the controversial 'ion filtration' mechanism.

  15. Proposal for a Graded Authorisation Model for the Use of Ionising Radiation in Ireland

    International Nuclear Information System (INIS)

    The Radiological Protection Institute of Ireland RPII intends to refocus, streamline and modernise its regulation of the use of ionising radiation in Ireland. This report provides detailed proposals for establishing a graded approach to authorisation in which regulators will be able to focus on higher risk practices by simplifying requirements placed on those of lower risk, without compromising the safety or security of the Irish population. These proposals build on RPII strategic analyses that seek to navigate a course between the competing pressures of public sector reform and the rapid technological changes in medical and nuclear arenas, which challenge the licensing and advisory functions of RPII. A graded approach to authorisation provides the potential for a sustainable basis for future regulation in Ireland. Such an approach would be in line with the forthcoming EURATOM Basic Safety Standards and with general current regulatory trends, which are moving away from one-size-fits-all approaches towards more adaptive, interactive and transparent regulation. In seeking this reform, the RPII also aims to fully utilize the benefits of the internet and electronic communications and to improve the transparency of its processes. These proposals have been developed using a robust, comprehensive project methodology involving a root and branch analysis of current and potential future approaches to authorisation. A series of facilitated workshops were held, punctuated by intensive periods of focused co-enquiry, involving all members of the RPII Regulatory Service. This approach made the fullest use of the decades of expertise and knowledge of these staff. It also provided the platform for developing a common vision of a graded approach to authorisation; for agreeing the criteria for differentiating between levels of authorisation; for collecting the necessary evidence for decision-making and for identifying the implications of these decisions. The graded approach presented

  16. γH2AX Foci Form Preferentially in Euchromatin after Ionising-Radiation

    Science.gov (United States)

    Cowell, Ian G.; Sunter, Nicola J.; Singh, Prim B.; Austin, Caroline A.; Durkacz, Barbara W.; Tilby, Michael J.

    2007-01-01

    Background The histone variant histone H2A.X comprises up to 25% of the H2A complement in mammalian cells. It is rapidly phosphorylated following exposure of cells to double-strand break (DSB) inducing agents such as ionising radiation. Within minutes of DSB generation, H2AX molecules are phosphorylated in large chromatin domains flanking DNA double-strand breaks (DSBs); these domains can be observed by immunofluorescence microscopy and are termed γH2AX foci. H2AX phosphorylation is believed to have a role mounting an efficient cellular response to DNA damage. Theoretical considerations suggest an essentially random chromosomal distribution of X-ray induced DSBs, and experimental evidence does not consistently indicate otherwise. However, we observed an apparently uneven distribution of γH2AX foci following X-irradiation with regions of the nucleus devoid of foci. Methodology/Principle Findings Using immunofluorescence microscopy, we show that focal phosphorylation of histone H2AX occurs preferentially in euchromatic regions of the genome following X-irradiation. H2AX phosphorylation has also been demonstrated previously to occur at stalled replication forks induced by UV radiation or exposure to agents such as hydroxyurea. In this study, treatment of S-phase cells with hydroxyurea lead to efficient H2AX phosphorylation in both euchromatin and heterochromatin at times when these chromatin compartments were undergoing replication. This suggests a block to H2AX phosphorylation in heterochromatin that is at least partially relieved by ongoing DNA replication. Conclusions/Significance We discus a number of possible mechanisms that could account for the observed pattern of H2AX phosphorylation. Since γH2AX is regarded as forming a platform for the recruitment or retention of other DNA repair and signaling molecules, these findings imply that the processing of DSBs in heterochromatin differs from that in euchromatic regions. The differential responses of

  17. DES ACCENTS ÉTRANGERS AUX ABORDS DE L’UTOPIE BROSSARDIENNE

    Directory of Open Access Journals (Sweden)

    Ghislaine Boulanger

    2011-12-01

    Full Text Available Cet article analyse l’analogie entre une langue sexiste et une langue étrangère, et démontre comment cette comparaison met en jeu des dimensions identitaires qui seront progressivement refoulées aux frontières de l’utopie féministe imaginée par Nicole Brossard. Cette étude met en relief certains problèmes d’exclusion reliés à la disparition symbolique de l’accent, tels que l’effacement de l’identité juive dans le roman Picture theory.

  18. La conquête de l’Algérie racontée aux enfants

    OpenAIRE

    Guillemette Tison

    2012-01-01

    L’histoire de la conquête de l’Algérie est racontée aux enfants aussi bien dans les manuels que dans les romans. Cet article propose d’examiner comment les années 1827 à 1847 sont restituées dans les ouvrages scolaires et non scolaires, par l’utilisation d’anecdotes récurrentes, par la mise en scène de figures de héros ou de collectivités.

  19. François-Ronan DUBOIS (2014), Introduction aux Porn Studies

    OpenAIRE

    Loubradou, Esther

    2015-01-01

    « La pornographie est un exemple typique de ces objets culturels dont le discours public s’empare volontiers sans jamais en produire une connaissance un tant soit peu détaillée » (p. 7). Cette connaissance partielle est pourtant regrettable et par rapport aux débats virulents entre discours anti-pornographiques et discours pro-sexe, la nécessité d’une posture compétente et objective sans perspective de condamnation ou de défense sur la pornographie se fait sentir. François-Ronan Dubois propos...

  20. Dialogisme et interdiscours : des discours coloniaux aux discours du développement

    OpenAIRE

    Dufour, Françoise

    2007-01-01

    Cet article explore l’articulation des notions de dialogisme et d’interdiscours à partir de l’analyse des reformulations repérables dans le passage des discours coloniaux aux discours du développement. L’analyse d’un corpus authentique de la formation discursive du développement permet de mettre en évidence différents niveaux de négociation avec l’hétérogénéité discursive auxquels l’énonciateur est soumis dans les nominations de l’autre. Les discours du développement interagissent dialogiquem...

  1. Conference - Découvrez notre région - Aux bornes de Genève

    CERN Multimedia

    Staff Association

    2016-01-01

      Les premières bornes-frontière sont posées en 1816 aux confins du royaume de Sardaigne, d’autres feront leur apparition dès 1818 du côté du royaume de France. Deux cents ans plus tard, on retrouve toujours ces pierres, témoins de la naissance du canton et patrimoine partagé des communes genevoises, gessiennes et savoisiennes qui font notre région.  

  2. Protection sociale et démocratie aux États-Unis

    OpenAIRE

    Ndiaye, Pap

    2000-01-01

    L'assurance et l'assistance sociale firent longtemps l'objet d'un consensus large dans la classe politique et la population américaines, particulièrement notable entre la fin de la Seconde Guerre mondiale et le début des années 1970, en apparaissant comme des piliers d'une démocratie moderne, capable de répondre aux défis posés par l'essor du grand capitalisme industriel. [Premier paragraphe de l'article

  3. Le capital-risque aux Etats-Unis dans les technologies de l'information

    OpenAIRE

    Patrice Boivin

    1999-01-01

    Aux États-Unis, les années 1990 consacrent la montée en puissance des fonds de capital-risque comme sources de financement pour les entreprises spécialisées dans les technologies de l'information. Plus précisément, les secteurs des logiciels et des communications reçoivent les montants les plus importants, en raison de leur potentiel de croissance lié au développement exponentiel d'Internet (accroissement des besoins de communication des entreprises et développement du commerce électronique)....

  4. Evaluation of the radiology state at the CEA/Fontenay-aux-Roses and its environment

    International Nuclear Information System (INIS)

    Since 1946 the nuclear installations followed one other at the CEA of Fontenay-aux-Roses still their gradual stop the last ten years, except two installations INB34 and INB73, necessary for the wastes management. Today these installations form the subject of a drainage program. The public opinion is regularly informed on this program since 1999. This document presents the stock of the actions realized since this date: the track keeping of the sites activities impacts on the environment and the actions realized since 1999. (A.L.B.)

  5. Letter: characterisation and identification of spermine and spermidine derivatives in Microdesmis keayana and Microdesmis puberula roots by electrospray ionisation tandem mass spectrometry and high-performance liquid chromatography/electrospray ionisation tandem mass spectrometry.

    Science.gov (United States)

    Roumy, Vincent; Hennebelle, Thierry; Zamblé, Alexis; Zamblé Yao, Jacques; Sahpaz, Sevser; Bailleul, François

    2008-01-01

    Three new N(1),N(5),N(14)-tris(4- hydroxycinnamoyl)spermines were identified in hydromethanolic root extracts of Microdesmis keayana J. Léonard and Microdesmis puberula Hook f. The electrospray ionisation tandem mass spectrometry (ESI-MS/MS) technique with specific nuclear magnetic resonance analysis of hydrolysed products made it possible to identify N(1),N(5),N(14)-tris(p-coumaroyl)spermine, N(1)-feruloyl,N(5),N(14)-di(p-coumaroyl)spermine and N(1),N(5),N(14)-tris(feruloyl)spermine, named keayanines B, C and D, respectively. ESI-MS/MS analysis most effectively provided structural data although high-performance liquid chromatography/electrospray ionisation tandem mass spectrometry was also used to characterise four other compounds from Microdesmis puberula-keayanidines A, B, C and keayanine A-which had already been identified in M. keayana. This chemical data is the first to be published for M. puberula which is a commonly used plant in Central African traditional medicine. PMID:18493101

  6. Est-on aux pizzas comme on est aux casseroles ? Sur les emplois métonymiques des syntagmes prépositionnels en à avec un nom d’objet

    Directory of Open Access Journals (Sweden)

    Hernandez Patricia

    2012-07-01

    Full Text Available Ce travail aborde les emplois spatiaux du type être à + article défini + nom d’objet (par exemple, être aux surgelés, aux casseroles, aux costumes, aux pizzas. De tels emplois sont compris, dans les ouvrages de spécialité comme des relations de localisation interprétables selon les connaissances partagées aussi bien sur le contexte d’énonciation que sur l’univers environnant. Sur la base de ce savoir lié aux routines établies, le repérage induit par la préposition à déclenche des inférences sur les interactions entre l’entité à situer et l’objet de référence. Notre parcours des descriptions existantes (Vandeloise 1988, Borillo 2001, Aurnague 2009, Corblin 2010 est suivi d’une réflexion, inspirée des principes de base de la sémantique cognitive (Langacker 1987, sur la nature de ces connexions. Ainsi, notre analyse prend en compte la corrélation entre objets et actions dans les rapports expérientiels entre l’être humain et son environnement : les lexèmes renvoyant aux entités dénotées offrent des clés d’accès à des routines et des synthèses d’expérience (Janet 1935, Brown 1965, Cadiot et Nemo 1997b. Ces scénarios, organisés en cadres d’interactions typiques (Fillmore 1982, fournissent un fond de connaissances permettant des connexions métonymiques par proximité conceptuelle selon des Modèles Cognitifs Idéalisés (Lakoff 1987, Radden & Kövecses 1999. Notre réflexion théorique est étayée par des occurrences attestées qui permettent de mieux saisir le rôle du contexte et des critères pragmatiques dans l’interprétation des formulations. En effet, sur la base d’une analyse contextuelle d’usages effectifs sur support électronique (Google France octobre 2011, nous présentons une ébauche de classement de ces emplois particuliers. La taxinomie proposée, qui ne se veut nullement définitive, conçoit les formulations en à avec des noms d’objet comme donnant un accès mental

  7. Assessing the surroundings for effects of ionising radiation on the granting of permits, DOVIS A. Emissions to air and water

    CERN Document Server

    Blaauboer, R O

    2002-01-01

    In the Netherlands, as in most other countries, one generally needs a permit to produce (including the manufacture, processing, control and storage), to apply or to dispose of radioactive materials, or to use equipment that produces ionising radiation. This permit must be in accordance with the Nuclear Energy Act. Limits that are set for radioactive material can be found in the Decree on radiation protection ('Besluit stralings-bescherming') which has been in force since March 1, 2002. Along with the application for a permit, calculation results have to be submitted on the radiation dose that members of the public receive as a consequence of (possible) emissions of radioactive material (into the atmosphere or surface water) or as a consequence of external irradiation. Fairly rough estimates, based on simple rules, will often be satisfactory. These rules can be found in an annex of a Ministerial Order on the assessment of consequences of ionising radiation (mr-AGIS). However, in some cases this will not be ade...

  8. Internet-based ICRP resource for healthcare providers on the risks and benefits of medical imaging that uses ionising radiation.

    Science.gov (United States)

    Demeter, S; Applegate, K E; Perez, M

    2016-06-01

    The purpose of the International Commission on Radiological Protection (ICRP) Committee 3 Working Party was to update the 2001 web-based module 'Radiation and your patient: a guide for medical practitioners' from ICRP. The key elements of this task were: to clearly identify the target audience (such as healthcare providers with an emphasis on primary care); to review other reputable sources of information; and to succinctly publish the contribution made by ICRP to the various topics. A 'question-and-answer' format addressing practical topics was adopted. These topics included benefits and risks of imaging using ionising radiation in common medical situations, as well as pertaining to specific populations such as pregnant, breast-feeding, and paediatric patients. In general, the benefits of medical imaging and related procedures far outweigh the potential risks associated with ionising radiation exposure. However, it is still important to ensure that the examinations are clinically justified, that the procedure is optimised to deliver the lowest dose commensurate with the medical purpose, and that consideration is given to diagnostic reference levels for particular classes of examinations. PMID:27012846

  9. The response of a neutral atom to a strong laser field probed by transient absorption near the ionisation threshold

    CERN Document Server

    Simpson, E R; Austin, D R; Diveki, Z; Hutchinson, S E E; Siegel, T; Ruberti, M; Averbukh, V; Miseikis, L; Strüber, C; Chipperfield, L; Marangos, J P

    2015-01-01

    We present transient absorption spectra of an extreme ultraviolet attosecond pulse train in helium dressed by an 800 nm laser field with intensity ranging from $2\\times10^{12}$ W/cm$^2$ to $2\\times10^{14}$ W/cm$^2$. The energy range probed spans 16-42 eV, straddling the first ionisation energy of helium (24.59 eV). By changing the relative polarisation of the dressing field with respect to the attosecond pulse train polarisation we observe a large change in the modulation of the absorption reflecting the vectorial response to the dressing field. With parallel polarized dressing and probing fields, we observe significant modulations with periods of one half and one quarter of the dressing field period. With perpendicularly polarized dressing and probing fields, the modulations of the harmonics above the ionisation threshold are significantly suppressed. A full-dimensionality solution of the single-atom time-dependent Schr\\"odinger equation obtained using the recently developed ab-initio time-dependent B-spline...

  10. On the Ionisation Fraction in Protoplanetary Disks II: The Effect of Turbulent Mixing on Gas--phase Chemistry

    CERN Document Server

    Ilgner, M; Ilgner, Martin; Richard P. Nelson

    2005-01-01

    We calculate the ionisation fraction in protostellar disk models using two different gas-phase chemical networks, and examine the effect of turbulent mixing by modelling the diffusion of chemical species vertically through the disk. The aim is to determine in which regions of the disk gas can couple to a magnetic field and sustain MHD turbulence. We find that the effect of diffusion depends crucially on the elemental abundance of heavy metals (magnesium) included in the chemical model. In the absence of heavy metals, diffusion has essentially no effect on the ionisation structure of the disks, as the recombination time scale is much shorter than the turbulent diffusion time scale. When metals are included with an elemental abundance above a threshold value, the diffusion can dramatically reduce the size of the magnetically decoupled region, or even remove it altogther. For a complex chemistry the elemental abundance of magnesium required to remove the dead zone is 10(-10) - 10(-8). We also find that diffusion...

  11. Optimisation of the quantitative determination of chlormequat by matrix-assisted laser desorption/ionisation mass spectrometry.

    Science.gov (United States)

    Horak, J; Werther, W; Schmid, E R

    2001-01-01

    The plant growth regulator chlormequat, an involatile quaternary ammonium salt, has been quantified by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOFMS). Restrictions for quantitative MALDI-TOFMS analysis, such as irreproducible crystallisation and unsatisfactory laser stability, have been overcome by the application of two synthesised isotopically labelled standards and the optimisation of the measurement protocol. Data acquisition at constant laser power was compared to data acquisition at approximately constant ion abundance of the relevant ions (analyte and internal standards). Data acquisition at constant ion abundance performed better and enabled a high number of consecutive firings to the same sample deposition area. Furthermore an increased sample-to-sample repeatability and a high reproducibility over several weeks without re-calibration have been attained by this method. Linearity over three orders of magnitude (0.05 to 30 ng/microL chlormequat), with a correlation coefficient of 0.9997, was achieved using [13C3]-chlormequat as internal standard. Limit of detection and limit of determination were determined to be in the low pg/microL range for pure standard solutions. Thin-layer chromatography was applied for the removal of high amounts of choline, which is often present in plant tissue extracts and can adversely affect the ionisation and detection of chlormequat by MALDI-TOFMS. The use of two internal standards ([13C3]- and [2H9]-chlormequat) enabled direct quantification and simultaneous control of the recovery. PMID:11223954

  12. Trefoil factor 3 (TFF3) enhances the oncogenic characteristics of prostate carcinoma cells and reduces sensitivity to ionising radiation.

    Science.gov (United States)

    Perera, Omesha; Evans, Angharad; Pertziger, Mikhail; MacDonald, Christa; Chen, Helen; Liu, Dong-Xu; Lobie, Peter E; Perry, Jo K

    2015-05-28

    Trefoil factor 3 (TFF3) is a secreted protein which functions in mucosal repair of the gastrointestinal tract. This is achieved through the combined stimulation of cell migration and prevention of apoptosis and anoikis, thus facilitating repair. Deregulated TFF3 expression at the gene and protein level is implicated in numerous cancers. In prostate cancer TFF3 has previously been reported as a potential biomarker, overexpressed in a subset of primary and metastatic cases. Here we investigated the effect of increased TFF3 expression on prostate cancer cell behaviour. Oncomine analysis demonstrated that TFF3 mRNA expression was upregulated in prostate cancer compared to normal tissue. Forced-expression models were established in the prostate cancer cell lines, DU145 and PC3, by stable transfection of an expression vector containing the TFF3 cDNA. Forced expression of TFF3 significantly increased total cell number and cell viability, cell proliferation and cell survival. In addition, TFF3 enhanced anchorage independent growth, 3-dimensional colony formation, wound healing and cell migration compared to control transfected cell lines. We also observed reduced sensitivity to ionising radiation in stably transfected cell lines. In dose response experiments, forced expression of TFF3 significantly enhanced the regrowth of PC3 cells following ionising radiation compared with control transfected cells. In addition, TFF3 enhanced clonogenic survival of DU145 and PC3 cells. These studies indicate that targeting TFF3 for the treatment of prostate cancer warrants further investigation.

  13. La sensibilisation aux valeurs liées à l’eau et à la bonne gouvernance

    OpenAIRE

    Smets, Henri

    2008-01-01

    Pour les économistes ‘traditionnels”, l’eau est une matière première indispensable à la vie humaine de la même manière que l’essence est indispensable aux moteurs des voitures et l’électricité aux ordinateurs. Aussi conviendrait-il, selon eux de traiter l’eau comme les autres marchandises et de la soumettre aux lois du marché afin d’en optimiser la gestion. Les difficultés concernant son approvisionnement et sa répartition entre les usagers seront automatiquement résolues par le mécanisme des...

  14. Les représentations sociales du travail dans des parcours de retour aux études aux niveaux collégial et universitaire

    Directory of Open Access Journals (Sweden)

    Claude Julie Bourque

    2009-10-01

    Full Text Available Cet article porte sur le volet éducatif de la production et de la reproduction de la main-d’œuvre hautement qualifiée par l’examen des processus en jeu au moment des retours aux études dans des programmes de formation technique et de génie. Nous nous intéressons en particulier à une situation emblématique des référentiels politiques récents en matière d’éducation, soit les retours aux études. Nous cherchons à mieux comprendre comment le retour aux études se réalise, comment les représentations professionnelles agissent sur ce dernier et comment l’expérience scolaire influence les projets des individus. Notre analyse met l’accent sur les ressorts sociaux et culturels des décisions relatives au choix de programmes et à l’orientation professionnelle d’étudiants qui ont interrompu leurs études et qui y retournent. Nous explorons le discours d’étudiants et d’étudiantes qui ont choisi de profiter de la souplesse du système d’éducation québécois pour compléter ou bonifier leur formation initiale ou encore pour tenter une réorientation professionnelle. En particulier, nous désirons savoir comment les différentes formes d’articulation entre éducation et travail influencent les représentations sociales des étudiants au sujet des titres scolaires, de l’évolution de leur carrière scolaire et de leur projet professionnel personnel.This paper deals with the educational aspect of the production and reproduction of highly qualified manpower through examining the processes at play when people return to school by enrolling in technical or engineering training programs. Our interest is focussed specifically on returning to school as an emblematic situation in recent educational policy frameworks. We are trying to better understand how school return is done, how professional representations act upon it and how previous school experience influences individual projects. Our analysis focuses on the

  15. Identification and expression analysis of primary auxin-responsive Aux/IAA gene family in cucumber (Cucumis sativus)

    Indian Academy of Sciences (India)

    Defang Gan; Dan Zhuang; Fei Ding; Zhenzhou Yu; Yang Zhao

    2013-12-01

    Aux/IAA is an important gene family involved in many aspects of growth and development. Aux/IAA proteins are short-lived nuclear proteins that are induced primarily by various phytohormones. In this study, 29 Aux/IAA family genes (CsIAA01–CsIAA29) were identified and characterized in cucumber, including gene structures, phylogenetic relationships, conserved protein motifs and chromosomal locations. These genes show distinct organizational patterns of their putative motifs. The distributions of the genes vary: except for five CsIAA genes in cucumber that were not located, seven CsIAA genes were found on scaffold, while the other 17 CsIAA genes were distributed on seven other chromosomes. Based on a phylogenetic analysis of the Aux/IAA protein sequences from cucumber, Arabidopsis and other plants, the Aux/IAA genes in cucumber were categorized into seven subfamilies. To investigate whether the expression of CsIAA genes is associated with auxin induction, their transcript levels were monitored in seedlings treated with IAA (indole-3-acetic acid), and their expression patterns were analysed by semiquantitative reverse transcription-polymerase chain reaction (RT-PCR). The results showed that 11/29 CsIAA genes were expressed in leaves whether treated with IAA or not and the time course of processing and compared with the control, five CsIAA genes showed low expression only after 60 min treatment with IAA, while 11 genes showed no expression. These results provide useful information for further functional analysis of Aux/IAA gene family in cucumber.

  16. Safety Training: Sensibilisation aux gestes et postures de travail

    CERN Multimedia

    Laetitia Laddada

    2004-01-01

    Nous vous proposons un nouveau cours de sécurité lié aux manutentions manuelles (durée 1 jour) : Sensibilisation aux gestes et postures de travail. Si vous êtes amené à manipuler régulièrement des charges lourdes ou volumineuses, cette formation peut vous aider à prévenir les lésions musculaires ou dorsales. A l'issue de cette formation, vous serez capable d'adopter et d'appliquer les principes de base de sécurité physique et d'économie d'efforts dans les manipulations d'objets. Les cours sont pris en charge par la Commission de Sécurité. L'inscription EDH est obligatoire. Pour plus d'information, veuillez consulter les pages Formation & Développement (Groupe Sécurité). Formation & Développement (Groupe Sécurité) FORMATION EN SECURITE SAFETY TRAINING Laetitia Laddada 73811 - 79236 safety.training@cern.ch

  17. Safety Training: Sensibilisation aux gestes et postures de travail

    CERN Multimedia

    Laetitia Laddada

    2004-01-01

    Nous vous proposons un nouveau cours de sécurité lié aux manutentions manuelles (durée 1 jour) : Sensibilisation aux gestes et postures de travail. Si vous êtes amené à manipuler régulièrement des charges lourdes ou volumineuses, cette formation peut vous aider à prévenir les lésions musculaires ou dorsales. A l'issue de cette formation, vous serez capable d'adopter et d'appliquer les principes de base de sécurité physique et d'économie d'efforts dans les manipulations d'objets. Les cours sont pris en charge par la Commission de Sécurité. L'inscription EDH est obligatoire. Pour plus d'information, veuillez consulter les pages Formation & Développement (Groupe Sécurité). Formation & Développement (Groupe Sécurité) FORMATION EN SECURITE SAFETY TRAINING Laetitia Laddada 73811 - 79236 sa...

  18. Edgar Morin, aux risques d'une pensée libre

    CERN Document Server

    Pena Vega, Alfredo

    2011-01-01

    8 juillet 2011 ; Edgar Morin fête ses 90 ans et 60 ans passés au sein du CNRS. Une occasion unique pour l'équipe d'Hermès et Dominique Wolton, d'analyser et de critiquer la pensée de ce grand intellectuel. Aspiration à la liberté, attention à la complexité du monde et une profonde originalité épistémologique, Edgar Morin a bouleversé aussi bien la philosophie, la politique que la physique ou les mathématiques. Avec un souci constant : faire communiquer et interagir toutes les sciences pour relever le défi de la compréhension. Plus qu'un simple hommage, ce numéro questionne l'œuvre d'Edgar Morin au filtre de la communication, dévoilant les mécaniques de cette vision du monde profondément originale, échappant aux cloisonnements et aux certitudes académiques, portée par un projet central, celui d'une réforme des connaissances. Suivant les cheminements intellectuels et politiques de ce chercheur itinérant et passionné à travers l'Europe, l'Est, l'Amérique latine ou les États-Unis, ce...

  19. ETUDE DE LA STABILITE AUX PETITES PERTURBATIONS DANS LES GRANDS RESEAUX ELECTRIQUES : OPTIMISATION DE LA REGULATION PAR UNE METHODE METAHEURISTIQUE

    OpenAIRE

    Alkhatib, Hasan

    2008-01-01

    Depuis une vingtaine d'années, les grands réseaux électriques se trouvent obligés de fonctionner à pleine puissance et souvent aux limites de la stabilité. L'amélioration de la stabilité aux petites perturbations, en particulier l'amortissement des oscillations interrégionales, est donc devenue un objectif prioritaire. Les interactions entre les générateurs de différentes régions et les régulateurs utilisés nécessitent une optimisation globale de leurs performances : c'est le meilleur moyen p...

  20. Transition des soins curatifs aux soins palliatifs dans un contexte de soins intensifs dans le cadre des soins infirmiers

    OpenAIRE

    Grzywack, Maurine; Meyer, Margaux; Ventimiglia, Valérie; Charmillot, Pierre-Alain

    2016-01-01

    Buts : Le travail de Bachelor, comprenant une revue de littérature et d’articles probants, comporte les objectifs suivants : 1) Mettre en évidence les différentes perceptions infirmières liées à la mort dans le contexte de soins intensifs par rapport aux soins palliatifs. 2) Relever les difficultés, obstacles, rencontrés par les professionnels de la discipline infirmière dans un milieu très aigu concernant la transition des soins curatifs aux soins palliatifs. 3) Mettre en lumière les interve...

  1. Field studies on long term ecosystem consequences of ionising radiation and chemical pollutants (EANOR Project)

    Energy Technology Data Exchange (ETDEWEB)

    Oughton, D. [Centre for Environmental Radioactivity - CERAD (Norway); Evseeva, T. [Institute of Biology RAS (Russian Federation); Erenturk, S. [Istanbul Technical University (Turkey)

    2014-07-01

    -barcoding, invertebrate DNA barcoding, DNA methylation, and other molecular endpoints is ongoing, together with studies of possible adaptation of plants, invertebrates and microorganisms. Preliminary results show significant differences in diversity for many species between contaminated and reference sites. However, more research is needed to draw conclusions about the cause of such observations. Nevertheless, by combining a through site characterisation and exposure assessment with a variety of ecologically relevant biomarker and endpoint measurements, the data produced should be a valuable contribution to international activities looking at the impacts of chronic exposure of ionising radiation on non-human species. Project participants: Elena Belykh, Anna Kaneva, Boris Kondratenok, Alla Kolesnikova, Alexey Kurdin, Tatinana Majstrenko, Taskayeva Anastasia Oleshya Vakhrusheva, Illa Velegzhaninov, Vladimir Zainullin (IoB, Komi Republic, Russia); S. Haciyakupoglu (Istanbul Technical University, Turkey); Rahime Oral, Sabriye Yusan, Filiz Gur Filiz (Ege University, Turkey); Murat Belivermis, Onder Kilic (Istanbul University, Turkey); Fatma Kocbas (Celal Bayar University, Turkey); Mustafa Akiner, (Rize University, Turkey); Claire Coutris, Erik Joner (Bioforsk, Norway); Turid Hertel-Aas, Emmanuel Lapied, Yevgeniya Tomkiv, Brit Salbu, Lindis Skipperud (Centre for Environmental Radioactivity, UMB, Norway). Document available in abstract form only. (authors)

  2. In situ analysis of Titan's tholins by Laser 2 steps Desorption Ionisation

    Science.gov (United States)

    Benilan, Y.; Carrasco, N.; Cernogora, G.; Gazeau, M.; Mahjoub, A.; Szopa, C.; Schwell, M.

    2013-12-01

    The main objective of the whole project developed in collaboration (LISA/LATMOS) is to provide a better understanding of the chemical composition of Titan aerosols laboratory analogs, called tholins, and thereby of their formation pathways. The tholins are produced in the PAMPRE reactor (French acronyme for Aerosols Microgravity Production by Reactives Plasmas) developed at LATMOS. These tholins are generated in levitation (wall effects are thus limited) in a low pressure radiofrequency plasma. Up to now, the determination of the physical and chemical properties of these tholins was achieved after their collection and ex-situ analysis by several methods. Their bulk composition was then determined but their insoluble part is still unknown. Other studies were performed after the transfer of the soluble part of the aerosols to different analytical instruments. Therefore, possible artifacts could have influenced the results. We present the SMARD (a French acronym for Mass Spectrometry of Aerosols by InfraRed Laser Desorption) program. A challenging issue of our work is to perform the soluble and unsoluble parts of PAMPRE tholins' analysis in real time and in situ. The coupling of the PAMPRE reactor to a unique instrument (Single Particle Laser Ablation Mass Spectrometry) developed at LISA should allow determining in real time and in situ the characteristics (chemical composition together with granulometry) of the nanometric aerosols. The later are introduced in the analytical instrument using an aerodynamic lens device. Their detection and aerodynamic diameter are determined using two continuous diode lasers operating at λ = 403 nm. Then, the L2DI (Laser 2 steps Desorption Ionisation) technique is used in order to access to the chemical composition of individual particles: they are vaporized using a 10 μm CO2 pulsed laser and the gas produced is then ionized by a 248 nm KrF Excimer laser. Finally, the molecular ions are analyzed by a 1 m linear time-of-flight mass

  3. Field studies on long term ecosystem consequences of ionising radiation and chemical pollutants (EANOR Project)

    International Nuclear Information System (INIS)

    -barcoding, invertebrate DNA barcoding, DNA methylation, and other molecular endpoints is ongoing, together with studies of possible adaptation of plants, invertebrates and microorganisms. Preliminary results show significant differences in diversity for many species between contaminated and reference sites. However, more research is needed to draw conclusions about the cause of such observations. Nevertheless, by combining a through site characterisation and exposure assessment with a variety of ecologically relevant biomarker and endpoint measurements, the data produced should be a valuable contribution to international activities looking at the impacts of chronic exposure of ionising radiation on non-human species. Project participants: Elena Belykh, Anna Kaneva, Boris Kondratenok, Alla Kolesnikova, Alexey Kurdin, Tatinana Majstrenko, Taskayeva Anastasia Oleshya Vakhrusheva, Illa Velegzhaninov, Vladimir Zainullin (IoB, Komi Republic, Russia); S. Haciyakupoglu (Istanbul Technical University, Turkey); Rahime Oral, Sabriye Yusan, Filiz Gur Filiz (Ege University, Turkey); Murat Belivermis, Onder Kilic (Istanbul University, Turkey); Fatma Kocbas (Celal Bayar University, Turkey); Mustafa Akiner, (Rize University, Turkey); Claire Coutris, Erik Joner (Bioforsk, Norway); Turid Hertel-Aas, Emmanuel Lapied, Yevgeniya Tomkiv, Brit Salbu, Lindis Skipperud (Centre for Environmental Radioactivity, UMB, Norway). Document available in abstract form only. (authors)

  4. Répondre aux suds : imaginaires et défis géopolitiques aux frontières du nord : cas du maroc et du mexique.

    Directory of Open Access Journals (Sweden)

    Philippe Sierra

    2010-11-01

    Full Text Available Maroc et Mexique sont deux Etats qui ont construit depuis une quinzaine d’années un nouveau discours et de nouvelles politiques pour valoriser leur proximité au « Nord ». Alena et Mexamérique d’un côté, quasi intégration au marché européen et péninsule tingitane de l’autre, sont devenues des lignes majeures des discours gouvernementaux. Cette valorisation des nords a provoqué une nouvelle vision des territoires nationaux, dans laquelle il faut répondre aux inquiétudes des suds, éloignés et sources de problèmes géopolitique tant au Mexique (la rébellion néo-zapatiste au Chiapas qu’au Maroc (le Sahara occidental. Cet article tente de montrer comment à travers les nouveaux plans de développement mis en place par les Etats pour répondre différemment à leurs inquiétudes, de nouvelles représentations géopolitiques révélatrices des « imaginaires du sud » se mettent en place auxquelles répondent des populations en soif d’identité.

  5. Formation of aluminium, aluminium nitride and nitrogen clusters via laser ablation of nano aluminium nitride. Laser Desorption Ionisation and Matrix-Assisted Laser Desorption Ionisation Time-of-Flight Mass Spectrometry.

    Science.gov (United States)

    Panyala, Nagender Reddy; Prysiazhnyi, Vadym; Slavíček, Pavel; Černák, Mirko; Havel, Josef

    2011-06-30

    Laser Desorption Ionisation (LDI) and Matrix-Assisted Laser Desorption Ionisation (MALDI) Time-of-Flight Mass Spectrometry (TOFMS) were used to study the pulsed laser ablation of aluminium nitride (AlN) nano powder. The formation of Al(m)(+) (m=1-3), N(n)(+) (n=4, 5), AlN(n)(+) (n=1-5, 19, 21), Al(m)N(+) (m=2-3), Al(3)N(2)(+), Al(9)N(n)(+) (n=5, 7, 9, 11 and 15), Al(11)N(n)(+) (n=4, 6, 10, 12, 19, 21, 23, and 25), and Al(13)N(n)(+) (n=25, 31, 32, 33, 34, 35, and 36) clusters was detected in positive ion mode. Similarly, Al(m)(-) (m=1-3), AlN(n)(-) (n=1-3, 5), Al(m)N(-) (n=2, 3), Al(2)N(n)(-) (n=2-4, 28, 30), N(n)(-) (n=2, 3), Al(4)N(7)(-) Al(8)N(n)(-) (n=1-6), and Al(13)N(n)(-) (n=9, 18, 20, 22, 24, 26, 28, 33, 35, 37, 39, 41 and 43) clusters were observed in negative ion mode. The formation of the stoichiometric Al(10) N(10) cluster was shown to be of low abundance. On the contrary, the laser ablation of nano-AlN led mainly to the formation of nitrogen-rich Al(m)N(n) clusters in both negative and positive ion mode. The stoichiometry of the Al(m)N(n) clusters was determined via isotopic envelope analysis and computer modelling.

  6. Formation of aluminium, aluminium nitride and nitrogen clusters via laser ablation of nano aluminium nitride. Laser Desorption Ionisation and Matrix-Assisted Laser Desorption Ionisation Time-of-Flight Mass Spectrometry.

    Science.gov (United States)

    Panyala, Nagender Reddy; Prysiazhnyi, Vadym; Slavíček, Pavel; Černák, Mirko; Havel, Josef

    2011-06-30

    Laser Desorption Ionisation (LDI) and Matrix-Assisted Laser Desorption Ionisation (MALDI) Time-of-Flight Mass Spectrometry (TOFMS) were used to study the pulsed laser ablation of aluminium nitride (AlN) nano powder. The formation of Al(m)(+) (m=1-3), N(n)(+) (n=4, 5), AlN(n)(+) (n=1-5, 19, 21), Al(m)N(+) (m=2-3), Al(3)N(2)(+), Al(9)N(n)(+) (n=5, 7, 9, 11 and 15), Al(11)N(n)(+) (n=4, 6, 10, 12, 19, 21, 23, and 25), and Al(13)N(n)(+) (n=25, 31, 32, 33, 34, 35, and 36) clusters was detected in positive ion mode. Similarly, Al(m)(-) (m=1-3), AlN(n)(-) (n=1-3, 5), Al(m)N(-) (n=2, 3), Al(2)N(n)(-) (n=2-4, 28, 30), N(n)(-) (n=2, 3), Al(4)N(7)(-) Al(8)N(n)(-) (n=1-6), and Al(13)N(n)(-) (n=9, 18, 20, 22, 24, 26, 28, 33, 35, 37, 39, 41 and 43) clusters were observed in negative ion mode. The formation of the stoichiometric Al(10) N(10) cluster was shown to be of low abundance. On the contrary, the laser ablation of nano-AlN led mainly to the formation of nitrogen-rich Al(m)N(n) clusters in both negative and positive ion mode. The stoichiometry of the Al(m)N(n) clusters was determined via isotopic envelope analysis and computer modelling. PMID:21598328

  7. A search for non-baryonic dark matter using an ionisation bolometer in the edelweiss experiment; Recherche de matiere sombre non-baryonique au moyen d`un bolometre a ionisation dans le cadre de l`experience edelweiss

    Energy Technology Data Exchange (ETDEWEB)

    Di Stefano, Ph. [CEA Saclay, 91 - Gif-sur-Yvette (France). Dept. d`Astrophysique, de la Physique des Particules, de la Physique Nucleaire et de l`Instrumentation Associee]|[Paris-11 Univ., 91 - Orsay (France)

    1998-09-24

    The EDELWEISS experiment is an underground direct-detection search for hypothetical supersymmetric WIMPs that might solve the problem of dark matter. We have employed a cryogenic 70 g germanium ionisation bolometer, in which a WIMP would scatter elastically off a nucleus, creating both a heat and an ionisation signal. To offset the various electronic noises present in our necessarily small signals, we have s applied an optimal filtering technique in the frequency domain. This allows us to reach resolutions of 1.2 keV FWHM at 122 keV on north channels. It also provides good separation right down to low energies between the expected signal of nuclear recoils, and the photonic background of electron recoils which ionize more for a given energy. Calibration data show that we are able to reject 99.7 % of this background, while keeping 95% of the signal. However, our 1.17 kg.days of data searching for WIMPs show a third population encroaching on the expected signal. This is probably due to low energy photons or electrons interacting in the outer layers of the crystal, where charges are incompletely collected. Nevertheless, by trading off half of the conserved signal, we still manage to reject 98.5 % of the background. Thus the raw rate of 40 evts/d/kg/keV yields a conservative 90 % upper limit on the signal of 0.6 evts/d/kg/keV. This represents nearly a three orders of magnitude improvement for EDELWEISS, and puts the predicted supersymmetric phase space within two orders of magnitude. (author) 196 refs.

  8. The Swedish radiation protection institute's regulations on general obligations in medical and dental practices using ionising radiation; issued on April 28, 2000

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-04-01

    These regulations are applicable to medical and dental practices with ionising radiation used for medical exposures. The regulations are also applicable to exposures of persons who knowingly and willingly, other than as part of their occupation, support and comfort patients undergoing medical exposure.

  9. Ion suppression in the determination of clenbuterol in urine by solid-phase extraction atmospheric pressure chemical ionisation ion-trap mass spectrometry

    NARCIS (Netherlands)

    van Hout, M.W.J.; Niederlander, H.A G; de Zeeuw, R.A.; de Jong, G.J.

    2003-01-01

    Ion suppression effects were observed during the determination of clenbuterol in urine with solid-phase extraction/multiple-stage ion-trap mass spectrometry (SPE/MS3), despite the use of atmospheric pressure chemical ionisation. During SPE, a polymeric stationary phase (polydivinylbenzene) was appli

  10. The Swedish radiation protection institute's regulations on general obligations in medical and dental practices using ionising radiation; issued on April 28, 2000

    International Nuclear Information System (INIS)

    These regulations are applicable to medical and dental practices with ionising radiation used for medical exposures. The regulations are also applicable to exposures of persons who knowingly and willingly, other than as part of their occupation, support and comfort patients undergoing medical exposure

  11. Investigation of colloidal graphite as a matrix for matrix-assisted laser desorption/ionisation mass spectrometry of low molecular weight analytes.

    Science.gov (United States)

    Warren, Alexander D; Conway, Ulric; Arthur, Christopher J; Gates, Paul J

    2016-07-01

    The analysis of low molecular weight compounds by matrix-assisted laser desorption/ionisation mass spectrometry is problematic due to the interference and suppression of analyte ionisation by the matrices typically employed - which are themselves low molecular weight compounds. The application of colloidal graphite is demonstrated here as an easy to use matrix that can promote the ionisation of a wide range of analytes including low molecular weight organic compounds, complex natural products and inorganic complexes. Analyte ionisation with colloidal graphite is compared with traditional organic matrices along with various other sources of graphite (e.g. graphite rods and charcoal pencils). Factors such as ease of application, spectra reproducibility, spot longevity, spot-to-spot reproducibility and spot homogeneity (through single spot imaging) are explored. For some analytes, considerable matrix suppression effects are observed resulting in spectra completely devoid of matrix ions. We also report the observation of radical molecular ions [M(-●) ] in the negative ion mode, particularly with some aromatic analytes. Copyright © 2016 John Wiley & Sons, Ltd.

  12. Identification of Wheat Varieties Using Matrix-assisted Laser Desorption/Ionisation Time-of-flight Mass Spectrometry and an Artificial Neural network

    DEFF Research Database (Denmark)

    Bloch, Helle Aagaard; Kesmir, Can; Petersen, Marianne Kjerstine;

    1999-01-01

    A novel tool for variety identification of wheat (Triticum aestivum L,) has been developed: an artificial neural network (ANN) is used to classify the gliadin fraction analysed by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOFMS). The robustness...

  13. Investigation of colloidal graphite as a matrix for matrix-assisted laser desorption/ionisation mass spectrometry of low molecular weight analytes.

    Science.gov (United States)

    Warren, Alexander D; Conway, Ulric; Arthur, Christopher J; Gates, Paul J

    2016-07-01

    The analysis of low molecular weight compounds by matrix-assisted laser desorption/ionisation mass spectrometry is problematic due to the interference and suppression of analyte ionisation by the matrices typically employed - which are themselves low molecular weight compounds. The application of colloidal graphite is demonstrated here as an easy to use matrix that can promote the ionisation of a wide range of analytes including low molecular weight organic compounds, complex natural products and inorganic complexes. Analyte ionisation with colloidal graphite is compared with traditional organic matrices along with various other sources of graphite (e.g. graphite rods and charcoal pencils). Factors such as ease of application, spectra reproducibility, spot longevity, spot-to-spot reproducibility and spot homogeneity (through single spot imaging) are explored. For some analytes, considerable matrix suppression effects are observed resulting in spectra completely devoid of matrix ions. We also report the observation of radical molecular ions [M(-●) ] in the negative ion mode, particularly with some aromatic analytes. Copyright © 2016 John Wiley & Sons, Ltd. PMID:27434807

  14. Ionisation in atmospheres of brown dwarfs and extrasolar planets VI: Properties of large-scale discharge events

    CERN Document Server

    Bailey, R L; Hodos, G; Bilger, C; Stark, C R

    2013-01-01

    Mineral clouds in substellar atmospheres play a special role as a catalyst for a variety of charge processes. If clouds are charged, the surrounding environment becomes electrically activated, and ensembles of charged grains are electrically discharging (e.g. by lightning), which significantly infuences the local chemistry creating conditions similar to those thought responsible for life in early planetary atmospheres. We note that such lightning discharges contribute also to the ionisation state of the atmosphere. We apply scaling laws for electrical discharge processes from laboratory measurements and numerical experiments to Drift-Phoenix model atmosphere results to model the discharge's propagation downwards (as lightning) and upwards (as sprites) through the atmospheric clouds. We evaluate the spatial extent and energetics of lightning discharges. The atmospheric volume affected (e.g. by increase of temperature or electron number) is larger in a brown dwarf atmosphere ($10^8 -~10^{10}$m$^3$) than in a gi...

  15. Etude, réalisation et caractérisation du transistor à ionisation par impact (I-MOS)

    OpenAIRE

    Mayer, Frédéric

    2008-01-01

    Le transistor à ionisation par impact (I-MOS) est une nouvelle architecture présentant l'avantage de s'affranchir de la barrière des 60mV/dec à température ambiante, qui limite la pente sous le seuil de l'architecture MOSFET classique. Le I-MOS se présente comme une diode PiN dont la zone intrinsèque est partiellement recouverte par une grille. L'objectif de cette thèse est d'évaluer les performances du I-MOS comme candidat potentiel à « l'après CMOS », à la fois du point de vue du dispositif...

  16. Role of the resistivity of insulating field emitters on the energy of field-ionised and field-evaporated atoms.

    Science.gov (United States)

    Arnoldi, L; Silaeva, E P; Vurpillot, F; Deconihout, B; Cadel, E; Blum, I; Vella, A

    2015-12-01

    In order to improve the accuracy of laser atom probe analyses, it is important to understand all the physical processes induced by the combination of the high electrical field and the femtosecond laser beam during field evaporation. New information can be accessed from the energy of evaporated surface atoms or field-ionised atoms of an imaging gas. In order to study the ions energy, we combine La-APT and FIM analyses in a new experimental setup equipped with electrostatic lenses. We report measurements for semiconductors and oxides and we study the influence of the illumination conditions (laser power and wavelength), the evaporation rate, the sample geometry and the tip preparation processes. The results are discussed taking into account the resistive properties of non-metallic samples and the photo-stimulated conductivity. This work clarifies the role of the laser and DC field in the energy deficit of field evaporated ions. PMID:25484362

  17. Low-energy total K-shell ionisation cross sections in the plane-wave Born approximation: an analytical result

    International Nuclear Information System (INIS)

    Starting from the general formulation of the plane-wave Born approximation (PWBA) an analytical expression for the low-energy total K-shell ionisation cross section is obtained. The reduced cross section is given as a power series in the adimensional parameters xi2 and theta which reproduces the values obtained by numerical integration within the precision inherent in the available tables. The universal part of the reduced cross section in the PWBA (that part of F(xi2,theta) that does not depend explicitly on theta) is expressed in terms of a few elementary analytical functions. The exact physical limits of integration are taken into account through the introduction of an effective parameter xisub(eff). (author)

  18. Medical and Dental Guidance Notes. A Good Practice Guide on all Aspects of Ionising Radiation Protection in the Clinical Environment

    International Nuclear Information System (INIS)

    Institute of Physics and Engineering in Medicine York: IPEM 225 pp, ISBN: 1-903613-09-4. This book is the much awaited replacement for the old yellow 'Guidance Notes' published in 1988 by the National Radiological Protection Board (NRPB). Since then nearly all Regulations covering the use of ionising radiation have been updated. The Institute of Physics and Engineering in Medicine (IPEM) established a working group in 1999 to produce a first draft for consultation (produced in April 2000) and to consider subsequent comments to this draft. The final document, published by IPEM, is therefore the end product of numerous contributions from professionals working in healthcare and wide consultation with professional bodies, the NRPB, UK Health Departments, Environment Agencies and the HSE. The notes provide general guidance on good practice - not just legal requirements. Radiation Protection Advisers and Medical Physics Experts may well have instigated slightly different arrangements locally. The publication has been available in electronic form on the IPEM website ( www.ipem.org.uk/publications/IRR99.html) for a few months. This has been useful for quick access to advice and for searching for particular topics but is difficult to read in large sections. Although it can be downloaded, the main documented is protected so that it can not be printed and specific text can not be 'cut and pasted'. The appendices are in a separate file that can be printed. Although the chapter paragraph numbers are consistent between the electronic and papers versions, the page numbers are different. The new guidance is ring bound, so, apart from at the beginning and end of the book, it is generally easy to open it out and lay it flat. The book consists of 19 chapters and 21 appendices and, with 225 pages, is considerably more extensive than the old notes. It begins with the general measures for radiation protection followed by radiation protection of persons undergoing medical exposures

  19. DNA radiation damage and asymmetric somatic hybridization: Is UV a potential substitute or supplement to ionising radiation in fusion experiments?

    International Nuclear Information System (INIS)

    Recent reports have revealed that the asymmetric nature of the nuclear genome of somatic hybrids, produced following the irradiation of one of the parents with X- or gamma rays, is generally much less than had been anticipated. As a consequence, we have begun to investigate whether UV radiation might be used as an alternative or indeed a supplement to the presently-used ionising radiation techniques in such experiments. Cell culture studies have revealed that UV radiation induces the desired physiological effects in sugar beet (Beta vulgaris) protoplasts, namely, a prevention of cell division without immediate cytotoxicity. Preliminary studies using denaturing and pulsed field gel electrophoresis have shown that UV can also induce substantial physical fragmentation of DNA. When using the same techniques, less breakdown was observed following gamma radiation. All results were highly reproducible. Such results augur well for the potential use of UV in asymmetric somatic cell fusion experiments. (author)

  20. La présence perturbatrice du Front national aux élections municipales

    OpenAIRE

    Perrineau, Pascal

    2014-01-01

    Depuis sa percée électorale aux élections européennes de 1984, le Front national a toujours atteint ses meilleurs niveaux lors des élections nationales et particulièrement lors de l'élection-reine qu'est l'élection présidentielle. Dans les cinq élections présidentielles qui se sont tenues depuis lors, il rassemble en moyenne presque 15% des suffrages exprimés (tableau 1). Les deux autres séries d'élections dans lesquelles il dépasse la barre des 10% des suffrages exprimés (s.e.) sont les élec...

  1. Chapitre 4. La Russie face aux révoltes libyenne et syrienne

    OpenAIRE

    De Tinguy, Anne

    2014-01-01

    Résumé : Face aux soulèvements dans le monde arabe, la Russie a glissé d’une attitude de compréhension à une prise de distance avec les stratégies adoptées par la majorité des États occidentaux et arabes, d’abord dans le cas libyen mais surtout dans le dossier syrien. Dans ses choix, la diplomatie russe est aussi bien guidée par des considérations stratégiques régionales (appui à un partenaire de longue date, ventes d’armes, facilités navales à Tartous, peur d’avoir à ses frontières un « seco...

  2. Introduction aux modèles espace état et au filtre de Kalman

    OpenAIRE

    Lemoine, Matthieu; Pelgrin, Florian

    2003-01-01

    Nous détaillons ici les principaux concepts et problèmes liés aux modèles espace-état, ainsi que leurs applications. Nous présentons d'abord ces modèles dans leur généralité. Ensuite, nous explicitons les algorithmes utilisés afin de procéder à l'estimation par le maximum de vraisemblance, c'est-à-dire fondamentalement le filtre de Kalman et l'algorithme EM. Nous considérons enfin quatre applications : les décompositions tendance-cycle, l'extraction d'indicateurs coïncidents d'activité, l'est...

  3. La lettre aux Colossiens: une théologie de la mémoire

    OpenAIRE

    Dettwiler, Andréas

    2013-01-01

    La lettre aux Colossiens - très probablement un document deutéropaulinien - peut être vue avant tout comme un remarquable effort théologique de mémoire. Si son auteur n'a pas l'ambition de dire quelque chose de réellement inédit, il y propose une relecture très originale de la tradition religieuse communément partagée entre lui et la communauté destinataire, pour offrir à celle-ci une interprétation qui donne sens à ce qu'elle vit dans une situation devenue de plus en plus opaque et conflictu...

  4. Des furoncles résistants aux antibiotiques: penser à la myiase !!

    Science.gov (United States)

    Ajili, Faida; Abid, Rim; Bousseta, Najeh; Mrabet, Ali; Karoui, Ghazi; Louzir, Bassem; Battikh, Riadh; Othmani, Salah

    2013-01-01

    Les myiases sont des infections parasitaires par des larves de mouches. La localisation cutanée doit être évoquée de retour d'un pays tropical devant une évolution inhabituelle de lésions cutanées. Nous rapportons une observation d'un militaire tunisien, ayant séjourné en République Démocratique du Congo. Il était atteint de myiase cutanée simulatrice d'une furonculose résistante aux antibiotiques. L'intérêt de cette observation est de souligner l'importance d’évoquer la myiase dont le traitement est simple et rapide chez un patient de retour de zone d'endémie. PMID:24106569

  5. Compartimentation microscopique: depuis les microchambres femtolitriques jusqu'aux particules pseudo-virales

    OpenAIRE

    Tresset, Guillaume

    2013-01-01

    Avec l'avènement de la microélectronique et des techniques de miniaturisation, de nouveaux domaines transdisciplinaires sont nés au confluent des sciences de l'ingénieur, de la matière et du vivant. La technologie a désormais investi l'échelle du nanomètre ; elle parvient à sonder, mais aussi surtout à façonner les constituants élémentaires de la matière synthétique et organique, depuis les atomes jusqu'aux complexes macromoléculaires. La nécessité d'isoler des molécules et des assemblages su...

  6. Observation spatiale et SIG: des outils pour cartographier les zones sensibles aux mouvements de terrain

    Directory of Open Access Journals (Sweden)

    Jean-Yves SCANVIC

    1994-12-01

    Full Text Available Les niveaux de sensibilité des sols aux mouvements de terrain ont été cartographiés dans différents bassins de risques en Bolivie, en Colombie et à Taïwan, selon une méthodologie développée au BRGM et fondée en partie sur l’extraction visuelle et numérique d’informations contenues dans les données de télédétection spatiale stéréoscopiques et leur gestion-valorisation dans un SIG. Ces cartes font apparaître l’intérêt de l’imagerie Spot pour la gestion du risque naturel.

  7. Former des enseignants pour faire apprendre aux élèves

    OpenAIRE

    Galand, Benoît; Entretiens Jacques Cartier, « Le déploiement à large échelle des meilleures pratiques pour soutenir la persévérance scolaire : un défi collectif. »

    2013-01-01

    Si le décrochage scolaire est clairement un phénomène multifactoriel, les recherches convergent pour mettre en avant le rôle proximal que joue l'expérience scolaire des élèves dans le processus d'abandon de l'école. Réfléchir aux pistes de prévention du décrochage en partant de ce constat amène à une série de défis imbriqués. Le premier de ces défis est d'identifier ce qui affecte l'expérience scolaire des élèves, pour la rendre plus positive. Il s'agit notamment de repérer les pratiques péda...

  8. Safety Training: Ergonomie - Sensibilisation aux gestes et postures de travail

    CERN Multimedia

    Laetitia Laddada

    2004-01-01

    Nous vous proposons un nouveau cours d'ergonomie (durée : 1 jour) Sensibilisation aux gestes et postures de travail. A l'issue de cette formation, vous serez capable d'adopter et d'appliquer les principes de base de sécurité physique et d'économie d'efforts dans les manipulations d'objets. Les cours sont pris en charge par la Commission de Sécurité. L'inscription EDH est obligatoire. Pour plus d'information, veuillez consulter les pages Formation & Développement (Groupe Sécurité). FORMATION EN SECURITE SAFETY TRAINING Laetitia Laddada 73811 - 79236 safety.training@cern.ch

  9. L'Ecole aux prises avec les idéologues de l'informatisation sociale

    OpenAIRE

    Thellen, Stéphane

    2002-01-01

    Cette communication s'inscrit dans une perspective sociologique de l'informatisation du champ éducatif. L'arrimage École / Société par le biais des nouvelles technologies de l'information et de la communication (NTIC) interpelle le sociologue, celui-ci s'étant toujours intéressé au procès de socialisation dans laquelle fut engagée l'École publique moderne. Or en ce début de 21ème siècle, le discours dominant sur l'informatisation des activités scolaires semble univoque : on prétend qu'aux pro...

  10. La panique pédophile aux États-Unis et en France

    OpenAIRE

    Kristen Zgoba; Mélanie-Angela Neuilly

    2005-01-01

    Durant la première moitié des années 1990, les États-Unis traversèrent ce qui peut être appelé une crise liée aux crimes sexuels. Ceci entraîna le passage de législations spécifiques destinées à adresser ce qui était perçu par le public comme un problème social de grande envergure. Durant la seconde moitié des années 1990, l’Europe (principalement l’Angleterre, la Belgique, les Pays-Bas, la France, et l’Allemagne) se trouva dans la même situation que les États-Unis. Là aussi des législations ...

  11. Jean-Philippe BELLEAU, Le mouvement indien au Brésil. Du village aux organisations

    OpenAIRE

    Fichet, Pascaline

    2015-01-01

    « Le mouvement indien au Brésil est un miracle », annonce l'accroche de la quatrième de couverture du dernier ouvrage de Jean-Philippe Belleau, Le mouvement indien au Brésil, Du village aux organisations. Depuis 1974, année de la première assemblée indigène brésilienne, les indiens du Brésil se sont progressivement constitués en acteurs modernes et éminents de l'espace politico-social national, à travers ce que l'auteur qualifiera de « mouvement indien » brésilien. Comment ces individus issus...

  12. Alternatives aux traitements anthelminthiques en élevage biologique des ruminants

    OpenAIRE

    Hoste, Hervé; Cabaret, Jacques; Grosmond, G.; Guitard, J.-P.

    2009-01-01

    En termes de gestion sanitaire des troupeaux, les recommandations du règlement de la commission européenne du 5 septembre 2008 (CE 889/2008), remplaçant le REPAB, visent à restreindre le recours aux traitements chimiques pour gérer les pathologies. Elles privilégient en contre-partie les règles d’hygiène et le développement de la réponse immune de l’animal. Ces principes généraux se retrouvent et sont illustrés dans la gestion du parasitisme helminthique par les strongles gastro-intestinaux q...

  13. Charles-Victor Langlois et Charles Seignobos, Introduction aux études historiques

    OpenAIRE

    Castellesi, Romain

    2014-01-01

    Positivistes, scientistes, fétichistes du document, généralistes : autant de qualificatifs utilisés par l’école des Annales, incarnées par un Lucien Febvre revanchard, et largement repris tout au long du XXe siècle pour critiquer les auteurs de L’Introduction aux études historiques, parue en 1898. L’intérêt nouveau suscité par l’ouvrage de Charles Seignobos et Charles-Victor Langlois signe t-il leur retour en grâce ? Dans sa préface inédite à cette nouvelle édition de l’ouvrage dans la toute ...

  14. Comparative evaluation of different approaches to environmental protection against ionising radiation in view of practicability and consistency

    Energy Technology Data Exchange (ETDEWEB)

    Steiner, M.; Hornung, L.; Mundigl, S.; Kirchner, G. [Federal Office for Radiation Protection, Salzgitter, (Germany)

    2006-07-01

    International organisations, including ICRP, IAEA and UNSCEAR, and the international scientific community are currently engaged in work on the protection of non-human species against ionising radiation as a complement to the existing framework centred on humans. The basic ideas and conceptual approaches developed during the last decade substantially agree with each other. The EC funded FASSET project (Framework for Assessment of Environmental Impact) summarizes and reviews the current knowledge of radiation effects on biota, provides basic dosimetric models for fauna and flora and suggests an assessment framework. Protection of the environment against ionising radiation, on the one hand, aims to close a conceptual gap in radiation protection. Therefore, current frameworks for environmental protection conceptually follow radiation protection of man. On the other hand, preservation of natural resources, habitats and the biological diversity are common objectives of environmental protection against radioactive as well as chemical pollutants, suggesting an integrated approach based on the fundamental ideas of conventional environmental protection. In essence, a conceptual framework encompassing protection of man as well as of fauna and flora against chemical and radioactive pollutants would be highly desirable in view of coherence, consistency and transparency. Such an umbrella concept communicates the positive message that similar issues are treated in a conceptually similar manner, thus facilitating scientific justification and public communication and increasing acceptance. This paper discusses different concepts and approaches to radiation protection of man, radiation protection of non-human biota and environmental protection against chemical pollutants, identifies common principles and differences, addresses conflicting requirements and evaluates the feasibility and limitations of such an encompassing framework. (authors)

  15. Detection of drugs in lifted cyanoacrylate-developed latent fingermarks using two laser desorption/ionisation mass spectrometric methods.

    Science.gov (United States)

    Sundar, Latha; Rowell, Frederick

    2014-02-01

    This paper describes a method for lifting cyanoacrylate (CNA)-developed latent fingermarks from a glass surface and the detection of five drugs in lifted marks from fingers that had been in contact with the drugs, using Surface Assisted Laser Desorption Ionisation Time of Flight Mass Spectrometry (SALDI-TOF-MS) or Matrix Assisted Laser Desorption Ionisation TOF-MS (MALDI-TOF-MS). Two drugs of abuse (cocaine and methadone) and three therapeutic drugs (aspirin, paracetamol and caffeine) were used as contact residues. Latent fingermarks spiked with the drugs were subjected to CNA fuming followed by dusting with ARRO SupraNano™ MS black magnetic powder (SALDI-TOF-MS) or 2,5-dihydroxybenzoic acid (DHB) (MALDI-TOF-MS). The dusted mark was then exposed to solvent vapour before lifting with a commercial fingerprint lifting tape following established procedures. The presence of the drugs was then confirmed by direct analysis on the tape without further processing using SALDI- or MALDI-TOF-MS. The black magnetic fingerprint powder provided visual enhancement of the CNA-fingermark while no visual enhancement was observed for marks dusted with DHB powder. Similar [M + H](+) peaks for all the drug analytes were observed for both methods along with some sodium and potassium adducts for SALDI-MS and some major fragment ions but the SALDI signals were generally more intense. Simple exposure to acetone vapour of the CNA-developed marks enabled their effective transfer onto the tape which was crucial for subsequent MS detection of the analytes.

  16. Comparative evaluation of different approaches to environmental protection against ionising radiation in view of practicability and consistency

    International Nuclear Information System (INIS)

    International organisations, including ICRP, IAEA and UNSCEAR, and the international scientific community are currently engaged in work on the protection of non-human species against ionising radiation as a complement to the existing framework centred on humans. The basic ideas and conceptual approaches developed during the last decade substantially agree with each other. The EC funded FASSET project (Framework for Assessment of Environmental Impact) summarizes and reviews the current knowledge of radiation effects on biota, provides basic dosimetric models for fauna and flora and suggests an assessment framework. Protection of the environment against ionising radiation, on the one hand, aims to close a conceptual gap in radiation protection. Therefore, current frameworks for environmental protection conceptually follow radiation protection of man. On the other hand, preservation of natural resources, habitats and the biological diversity are common objectives of environmental protection against radioactive as well as chemical pollutants, suggesting an integrated approach based on the fundamental ideas of conventional environmental protection. In essence, a conceptual framework encompassing protection of man as well as of fauna and flora against chemical and radioactive pollutants would be highly desirable in view of coherence, consistency and transparency. Such an umbrella concept communicates the positive message that similar issues are treated in a conceptually similar manner, thus facilitating scientific justification and public communication and increasing acceptance. This paper discusses different concepts and approaches to radiation protection of man, radiation protection of non-human biota and environmental protection against chemical pollutants, identifies common principles and differences, addresses conflicting requirements and evaluates the feasibility and limitations of such an encompassing framework. (authors)

  17. Application of the Alkaline Comet Assay and the Analysis of Structural Chromosome Aberrations in Assessment of Genetic Damage After Accidental Exposure to Ionising Radiation

    International Nuclear Information System (INIS)

    Full text: Living with the effects of low-level ionising radiation is one of the normal hazards of life. However, the effects of lower doses may not show up for years after exposure and are due to various changes in DNA molecules and chromosomes. Radiation-induced mutations seem to be brought about by the deletion of small pieces of chromosomes during the process of chromosome breakage and repair. Since chromosome damage is most likely to happen in dividing cells, ionising radiation usually cause cancer in those parts of the body where cells are actively dividing. Ionising radiation kills rapidly dividing cells, blood lymphocytes among them. People are exposed to high doses of ionising radiation when radiation accidents occur. The cytogenetical consequences of accidental exposure to gamma-radiation (radiation dose 221 mSv) were investigated by using alkaline Comet assay and the analysis of structural chromosomal aberrations (CA). Blood samples were repeatedly collected during one-year period after the accident. By using the Comet assay immediately after accidental exposure a high level of DNA damage was recorded. Although this level was decreasing over a one-year period, it was still elevated compared to normal values of DNA damage for unexposed persons. Immediately after the accident prevalence of CA (dicentrics, acentrics) over chromatid aberrations was recorded. However, one year afterwards only a few chromatid breaks were recorded. Our results confirmed usefulness of the alkaline Comet assay as a simple and sensitive technique for the biomonitoring of DNA damages, especially in the cases of accidental exposure to ionising radiation. (author)

  18. Adenosine Diphosphate Ribosylation Factor-GTPaseActivating Protein Stimulates the Transport of AUX1Endosome, Which Relies on Actin Cytoskeletal Organization in Rice Root DevelopmentF

    Institute of Scientific and Technical Information of China (English)

    Cheng Du; Yunyuan XU; Yingdian Wang; Kang Chong

    2011-01-01

    Polar auxin transport,which depends on polarized subcellular distribution of AUXIN RESISTANT 1/LIKE AUX1 (AUX1/LAX) influx carriers and PIN-FORMED (PIN) efflux carriers,mediates various processes of plant growth and development.Endosomal recycling of PIN1 is mediated by an adenosine diphosphate (ADP)ribosylation factor (ARF)-GTPase exchange factor protein,GNOM.However,the mediation of auxin influx carrier recycling is poorly understood.Here,we report that overexpression of OsAGAP,an ARF-GTPase-activating protein in rice,stimulates vesicle transport from the plasma membrane to the Golgi apparatus in protoplasts and transgenic plants and induces the accumulation of early endosomes and AUX1.AUX1 endosomes could partially colocalize with FM4-64 labeled early endosome after actin disruption.Furthermore,OsAGAP is involved in actin cytoskeletal organization,and its overexpression tends to reduce the thickness and bundling of actin filaments.Fluorescence recovery after photobleaching analysis revealed exocytosis of the AUX1 recycling endosome was not affected in the OsAGAP overexpression cells,and was only slightly promoted when the actin filaments were completely disrupted by Lat B.Thus,we propose that AUX1 accumulation in the OsAGAP overexpression and actin disrupted cells may be due to the fact that endocytosis of the auxin influx carrier AUX1 early endosome was greatly promoted by actin cytoskeleton disruption.

  19. Protection of the environment from ionising radiation. The development and application of a system of radiation protection for the environment. Proceedings of the third international symposium on the protection of the environment from ionising radiation (SPEIR 3). Unedited papers

    International Nuclear Information System (INIS)

    In recent years, awareness of the vulnerability of the environment has increased, as evidenced by new and developing international policies for environmental protection, starting with the Rio Declaration of 1992. In the context of ionizing radiation, the existing international approach is largely based on providing for the protection of humans, but this is being critically reviewed in several international fora. It is in this context that the Third International Symposium on Protection of the Environment from Ionising Radiation (SPEIR 3) was held between 22 and 26 July 2002, in Darwin, Australia. The symposium focused on issues related to the development and application of a system of radiation protection for the environment. The symposium programme included sessions dedicated to: ongoing research on the effects, responses and mechanisms of the interactions of ionizing radiation with biota; policy and ethical dimensions of the development of a framework for environmental radiation protection; and the development and use of methods and models for evaluating radiation as a stressor to the environment. Three workshops were held to allow for detailed discussion of each of these subjects. This symposium was the third in a series. The first International Symposium on Ionising Radiation: Protection of the Natural Environment, was held in Stockholm, Sweden, 20-24 May 1996. This symposium was organized jointly by the Swedish Radiation Protection Institute (SSI) and the Atomic Energy Control Board (AECB) of Canada, and the proceedings were published by the Akademitryck AB, Edsbruk, Sweden in 1996. The second International Symposium on Ionizing Radiation: Environmental Protection Approaches for Nuclear Facilities, was held in Ottawa, Canada, 10-14 May 1999, and was organized by the Canadian Nuclear Safety Commission (CNSC), the Supervising Scientists Group of Environment Australia, and the Swedish Radiation Protection Institute (SSI). The proceedings were published in April

  20. Etude sur les tendons en materiaux composites et leur application aux ancrages postcontraints

    Science.gov (United States)

    Chennouf, Adil

    L'objectif general de la presente these est d'evaluer le comportement a l'arrachement et au fluage d'ancrages injectes constitues de tendons en materiaux composites afin d'etablir des recommandations plus appropriees et realistes pour le dimensionnement et la conception. Quatre types de tendons en materiaux composites, deux a base de fibres d'aramide et deux a base de fibres de carbone, ont ete utilises dans l'etude. Les travaux de recherche de cette these ont porte notamment sur: (I) Une caracterisation physique et mecanique des tendons en materiaux composites utilises dans l'etude. (II) Une etude en laboratoire sur les coulis de scellement. La premiere etape de cette etude a concerne le developpement d'un coulis de scellement performant adapte aux tendons en materiaux composites et a differentes situations d'injection. La seconde etape a traite des essais de caracterisations physique et mecanique du coulis de scellement developpe comparativement a trois coulis de scellement usuels d'un meme rapport E/L de 0,4. (III) Une etude sur des modeles reduits d'ancrages injectes. (IV) Une etude sur des modeles d'ancrages a grande echelle. La synthese de ces etudes a permis d'enoncer les principales conclusions suivantes: (1) Les valeurs moyennes des charges de rupture des tendons en materiaux composites ont ete de 1% a 29% superieures a celles specifiees par les manufacturiers. (2) L'etude sur les coulis de scellement a permis le developpement de coulis de ciment repondant aux criteres fixes, soient une grande stabilite, une bonne fluidite, une legere expansion et de bonnes caracteristiques mecaniques. (3) Les tendons en materiaux composites ont montre des contraintes d'adherence maximum superieures a celles des tendons en acier. (4) Le type de fibre, la configuration et le fini de surface des tendons en materiaux composites gouvernent leur resistance a l'adherence. (5) L'introduction de sable et d'autres ajouts comme les fines de silice et la poudre d'aluminium au coulis

  1. Modelisation de la diffusion sur les surfaces metalliques: De l'adatome aux processus de croissance

    Science.gov (United States)

    Boisvert, Ghyslain

    Cette these est consacree a l'etude des processus de diffusion en surface dans le but ultime de comprendre, et de modeliser, la croissance d'une couche mince. L'importance de bien mai triser la croissance est primordiale compte tenu de son role dans la miniaturisation des circuits electroniques. Nous etudions ici les surface des metaux nobles et de ceux de la fin de la serie de transition. Dans un premier temps, nous nous interessons a la diffusion d'un simple adatome sur une surface metallique. Nous avons, entre autres, mis en evidence l'apparition d'une correlation entre evenements successifs lorsque la temperature est comparable a la barriere de diffusion, i.e., la diffusion ne peut pas etre associee a une marche aleatoire. Nous proposons un modele phenomenologique simple qui reproduit bien les resultats des simulations. Ces calculs nous ont aussi permis de montrer que la diffusion obeit a la loi de Meyer-Neldel. Cette loi stipule que, pour un processus active, le prefacteur augmente exponentiellement avec la barriere. En plus, ce travail permet de clarifier l'origine physique de cette loi. En comparant les resultats dynamiques aux resultats statiques, on se rend compte que la barriere extraite des calculs dynamiques est essentiellement la meme que celle obtenue par une approche statique, beaucoup plus simple. On peut donc obtenir cette barriere a l'aide de methodes plus precises, i.e., ab initio, comme la theorie de la fonctionnelle de la densite, qui sont aussi malheureusement beaucoup plus lourdes. C'est ce que nous avons fait pour plusieurs systemes metalliques. Nos resultats avec cette derniere approche se comparent tres bien aux resultats experimentaux. Nous nous sommes attardes plus longuement a la surface (111) du platine. Cette surface regorge de particularites interessantes, comme la forme d'equilibre non-hexagonale des i lots et deux sites d'adsorption differents pour l'adatome. De plus, des calculs ab initio precedents n'ont pas reussi a confirmer la

  2. Order of 30 March 1988 on licensing of gaseous radioactive effluent releases by the Fontenay-aux-Roses Nuclear Research Centre

    International Nuclear Information System (INIS)

    This Decree prescribes the documents and information the Fontenay-aux-Roses Nuclear Research Centre must provide to the Central Service for Protection against Ionizing Radiation (SCPRI) and lays down the permissible effluent release limits for the Centre

  3. L’utilisation du vaccin contre l’influenza chez les enfants allergiques aux œufs

    OpenAIRE

    Hui, Charles PS; MacDonald, Noni E

    2011-01-01

    Les enfants sont plus vulnérables à la morbidité attribuable à l’influenza. Les vaccins contre l’influenza sont cultivés sur des œufs et pour cette raison, une infime quantité de protéines d’œuf persiste dans leur composition. De récentes recherches et de nouveaux paramètres de pratique suscités par la pandémie mondiale d’influenza de 2009 ont remis en question la décision de ne pas administrer le vaccin contre l’influenza aux patients allergiques aux œufs. Selon les données disponibles, l’an...

  4. Inégalités sociales dans le renoncement aux soins de santé et dans leur utilisation

    OpenAIRE

    Tchicaya, Anastase; Lorentz, Nathalie

    2011-01-01

    Cette recherche se focalise sur l’analyse des inégalités sociales associées à l’accès et à l’utilisation des services de soins médicaux et hospitaliers au Luxembourg. Les données utilisées proviennent des enquêtes PSELL3/EU-SILC réalisées chaque année sur un échantillon représentatif de la population luxembourgeoise vivant en ménage privé. Des indicateurs d’accès aux soins (ou de renoncement aux soins) et d’utilisation des services de santé sont définis et les principales mesures d’inégalité ...

  5. Periodicity, Electronic Structures, and Bonding of Gold Tetrahalides [AuX4](-) (X = F, CI, Br, I, At, Uus)

    Energy Technology Data Exchange (ETDEWEB)

    Li, Wan-Lu; Li, Yong; Xu, Congqiao; Wang, Xue B.; Vorpagel, Erich R.; Li, Jun

    2015-12-07

    Systematic theoretical and experimental investigations have been performed to understand the periodicity and electronic structures of trivalent-gold halides using gold tetrahalides [AuX4]⁻ anions (X = F, Cl, Br, I, At, Uus). The [AuX4]⁻ (X = Cl, Br, I) anions were produced in gas phase and their negative-ion photoelectron spectra were obtained, which exhibited rich and well-resolved spectral peaks. We calculated the adiabatic as well as vertical electron detachment energies using density functional methods with scalar and spin-orbit coupling relativistic effects. The simulated photoelectron spectra based on these calculations are in good agreement with the experimental spectra. Our results show that the trivalent Au(III) oxidation state becomes progressively less stable while Au(I) is preferred when the halides become heavier along the Period Table. This trend reveals that the oxidation state of metals in complexes can be manipulated through ligand design

  6. Annliese Nef, Conquérir et gouverner la Sicile islamique aux XIe et XIIe siècles

    OpenAIRE

    Lejbowicz, Max

    2012-01-01

    625 pages de texte abondamment annotées, 106 d’annexes de nature diverse (iconographique, tabulaire, lexicographique, onomastique), 57 consacrées aux Sources et bibliographie, 13 à quatre Index, 5 aux abréviations, sans compter, intégrés au texte, sept figures (en fait des cartes et des plans) et dix-huit tableaux : l’ouvrage sous examen a l’épaisseur et le sérieux d’une thèse. Plus précisément : il est « la version profondément remaniée d’une thèse de doctorat soutenue en 2001 » (p. 9). Rapp...

  7. Ionisation and dissociation of water induced by swift multicharged ions; Etude de l'ionisation et de la dissociation d'H{sub 2}O induites par collision avec des ions multicharges rapides

    Energy Technology Data Exchange (ETDEWEB)

    Legendre, S

    2006-02-15

    Ionization and dissociation of water molecules and water clusters induced by 11.7 MeV/A Ni{sup 25+} ions were carried out by imaging techniques. Branching ratios, ionisation cross sections and Kinetic Energy Released distributions have been measured together with fragmentation dynamics studies. Multiple ionization represents approximately 30% of the ionizing events. Double ionization produces in significant way atomic oxygen, considered as a possible precursor of the large production of HO{sub 2} radical in liquid water radiolysis by ions of high Linear Energy Transfer. We evidence a strong selectivity of bond breakage in the case of ion-induced HOD fragmentation. Once the molecule doubly ionized, the breakage of the O-H bond is found 6.5 times more probable than that of the O-D bond. A semi-classical calculation simulating the fragmentation dynamics on the potential energy surface of the ground-state of di-cation H{sub 2}O{sup 2+} makes possible to as well reproduce the preferential nature of the breakage of the O-H bond as the position and the shift of the kinetic energy distributions. First results concerning interaction with water clusters are also reported. Measurements in coincidence are carried out giving access to correlation, with the distributions in energy and angle of the emitted fragments. Mass spectrum points fast intra-cluster proton transfer, leading to the emission of protonated clusters. (author)

  8. The SILCC project --- IV. Impact of dissociating and ionising radiation on the interstellar medium and Halpha emission as a tracer of the star formation rate

    CERN Document Server

    Peters, Thomas; Walch, Stefanie; Glover, Simon C O; Girichidis, Philipp; Pellegrini, Eric; Klessen, Ralf S; Wünsch, Richard; Gatto, Andrea; Baczynski, Christian

    2016-01-01

    We present three-dimensional radiation-hydrodynamical simulations of the impact of stellar winds, photoelectric heating, photodissociating and photoionising radiation, and supernovae on the chemical composition and star formation in a stratified disc model. This is followed with a sink-based model for star clusters with populations of individual massive stars. Stellar winds and ionising radiation regulate the star formation rate at a factor of ~10 below the simulation with only supernova feedback due to their immediate impact on the ambient interstellar medium after star formation. Ionising radiation (with winds and supernovae) significantly reduces the ambient densities for most supernova explosions to rho = 30 M_sun) with short lifetimes are responsible for significant fluctuations in the Halpha luminosities. The corresponding inferred star formation rates can underestimate the true instantaneous star formation rate by factors of ~10.

  9. State-of-the-art thermal ionisation mass spectrometry (TIMS) - an analytical technique approaching its 100th “birthday” and still going strong

    International Nuclear Information System (INIS)

    The first report of analyses of ion beams (or “positive rays” as they were called at the time) produced by thermal ionisation and using a magnetic sector field was published 97 years ago (A.J.Dempster; Phys. Rev. 11 (1918), p 316). In the meantime the technique has developed a lot and TIMS is still the method of choice for many applications in various fields of research. No other technique can routinely achieve higher reproducibility for the analysis of selected isotope ratios than TIMS (e.g. 2-3 ppm relative standard deviation for Sr or Nd). This presentation will introduce the hardware and the procedures required to achieve such high-precision measurements. Also, the current status of a development of the TIMS ion source will be presented, the thermal ionisation cavity source. (author)

  10. Large scale opacity fluctuations in the Lyman alpha forest: evidence for QSOs dominating the ionising UV background at z ~ 5.5-6 ?

    CERN Document Server

    Chardin, Jonathan; Haehnelt, Martin G

    2016-01-01

    Lyman-alpha forest data probing the post-reionization Universe shows surprisingly large opacity fluctuations over rather large ($\\ge$50 comoving Mpc/h) spatial scales. We model these fluctuations using a hybrid approach utilizing the large volume Millennium simulation to predict the spatial distribution of QSOs combined with smaller scale full hydrodynamical simulation performed with RAMSES and post-processed with the radiative transfer code ATON. We produce realictic mock absorption spectra that account for the contribution of galaxies and QSOs to the ionising UV background. This improved models confirm our earlier findings that a significant ($\\ge$50%) contribution of ionising photons from QSOs can explain the large reported opacity fluctuations on large scales. The inferred QSO luminosity function is thereby consistent with recent estimates of the space density of QSOs at this redshift. Our simulations still somewhat struggle, however, to reproduce the very long (110 comoving Mpc/h) high opacity absorption...

  11. Phloem-specific expression of a melon Aux/IAA in tomato plants alters auxin sensitivity and plant development

    Directory of Open Access Journals (Sweden)

    Guy eGolan

    2013-08-01

    Full Text Available Phloem sap contains a large repertoire of macromolecules in addition to sugars, amino acids, growth substances and ions. The transcription profile of melon phloem sap contains over 1,000 mRNA molecules, most of them associated with signal transduction, transcriptional control, and stress and defense responses. Heterografting experiments have established the long-distance trafficking of numerous mRNA molecules. Interestingly, several trafficking transcripts are involved in the auxin response, including two molecules coding for auxin/indole acetic acid (Aux/IAA. To further explore the biological role of the melon Aux/IAA transcript CmF-308 in the vascular tissue, a cassette containing the coding sequence of this gene under a phloem-specific promoter was introduced into tomato plants. The number of lateral roots was significantly higher in transgenic plants expressing CmF-308 under the AtSUC2 promoter than in controls. A similar effect on root development was obtained after transient expression of CmF-308 in source leaves of N. benthamiana plants. An auxin-response assay showed that CmF-308-transgenic roots are more sensitive to auxin than control roots. In addition to the altered root development, phloem-specific expression of CmF-308 resulted in shorter plants, a higher number of lateral shoots and delayed flowering, a phenotype resembling reduced apical dominance. In contrast to the root response, cotyledons of the transgenic plants were less sensitive to auxin than control cotyledons. The reduced auxin sensitivity in the shoot tissue was confirmed by lower relative expression of several Aux/IAA genes in leaves and an increase in the relative expression of a cytokinin-response regulator, TRR8/9b. The accumulated data suggest that expression of Aux/IAA in the phloem modifies auxin sensitivity in a tissue-specific manner, thereby altering plant development.

  12. Second meeting of the Atomic and Molecular Data Centre network. Fontenay aux Roses, 23-24 May 1980

    International Nuclear Information System (INIS)

    Summary report of the Second A+M Data Centre Network (DCN) meeting convened by the IAEA Nuclear Data Section at the CEA Laboratory at Fontenay-aux-Roses, France, 23-24 May 1980. The meeting was attended by 20 representatives from centres and groups from six Member States concerned with the coordinated international management of atomic and molecular data pertinent to controlled fusion research and technology

  13. Distribution et extension de la résistance chloroplatique aux atrazines chez les adventices annuelles en France

    OpenAIRE

    GASQUEZ, Jacques; BARRALIS, Gilbert; Aigle, N.

    1982-01-01

    La résistance chloroplastique aux triazines a été observée en France chez 13 espèces, dont les auteurs précisent l’importance agronomique et la distribution géographique ; les 3 espèces qui présentent la plus grande dispersion sont Amaranthus retroflexus L., Chenopodium album L. et Solanum nigrum L.

  14. La politique européenne d’aide à la mise aux normes de qualité

    Directory of Open Access Journals (Sweden)

    Vialatte Philippe

    2001-05-01

    Full Text Available La Commission européenne peut aider les pays en développement à financer des programmes de mise aux normes de qualité pour contribuer à la lutte contre la pauvreté, améliorer les conditions de vie des populations locales et leur permettre de bénéficier encore plus largement des opportunités offertes par le marché européen.

  15. Comparison of VITEK 2 YST Card and API 20C AUX system in identification of non- albicans Candida species

    Directory of Open Access Journals (Sweden)

    Süleyman Durmaz

    2012-03-01

    Full Text Available Objectives: In the present study, it was aimed to compare results obtained by using VITEK 2 YST Card (bioMérieux, France with those obtained by using API 20C AUX (bioMérieux, France for identification of non- albicans Candida species, which was isolated from various clinical samples, at level of species.Materials and methods: Forty-one non-albicans Candida isolates, which were isolated from 28 urine, 10 blood and 3 vaginal swab specimens, and found to be negative by germ tube test, were identified by using VITEK 2 YST Card (bioMérieux, France. In addition, microscopic morphology was assessed in corn-meal Tween 80 agar, while carbohydrate assimilation was assessed by using commercially available API 20C AUX kit (bioMérieux, France.Results: Thirty-four isolates (82.9% were identified as identical species by these 2 systems, while different results were obtained in 7 isolates (17.1%. 5 isolates, identified as Candida glabrata by API 20C AUX system, were identified as Candida tropicalis (n=2, Candida krusei, Candida lipolitica and Candida kefyr by VITEK 2 YST Card. One other isolate, identified as C.tropicalis, was identified as Candida parapsilosis; and additional one isolate, identified as C.parapsilosis, was identified as C.tropicalis.Conclusion: It was concluded that one should be cautious in the identification of C.glabrata, in particular, C.tropicalis and C.parapsilosis, although between VITEK 2 YST Card and API 20C AUX system results was found largely similarity in identification of non-albicans Candida spp.

  16. The tomato Aux/IAA transcription factor IAA9 is involved in fruit development and leaf morphogenesis.

    Science.gov (United States)

    Wang, Hua; Jones, Brian; Li, Zhengguo; Frasse, Pierre; Delalande, Corinne; Regad, Farid; Chaabouni, Salma; Latché, Alain; Pech, Jean-Claude; Bouzayen, Mondher

    2005-10-01

    Auxin/indole-3-acetic acid (Aux/IAA) proteins are transcriptional regulators that mediate many aspects of plant responses to auxin. While functions of most Aux/IAAs have been defined mainly by gain-of-function mutant alleles in Arabidopsis thaliana, phenotypes associated with loss-of-function mutations have been scarce and subtle. We report here that the downregulation of IAA9, a tomato (Solanum lycopersicum) gene from a distinct subfamily of Aux/IAA genes, results in a pleiotropic phenotype, consistent with its ubiquitous expression pattern. IAA9-inhibited lines have simple leaves instead of wild-type compound leaves, and fruit development is triggered before fertilization, giving rise to parthenocarpy. This indicates that IAA9 is a key mediator of leaf morphogenesis and fruit set. In addition, antisense plants displayed auxin-related growth alterations, including enhanced hypocotyl/stem elongation, increased leaf vascularization, and reduced apical dominance. Auxin dose-response assays revealed that IAA9 downregulated lines were hypersensitive to auxin, although the only early auxin-responsive gene that was found to be upregulated in the antisense lines was IAA3. The activity of the IAA3 promoter was stimulated in the IAA9 antisense genetic background, indicating that IAA9 acts in planta as a transcriptional repressor of auxin signaling. While no mutation in any member of subfamily IV has been reported to date, the phenotypes associated with the downregulation of IAA9 reveal distinct and novel roles for members of the Aux/IAA gene family. PMID:16126837

  17. SIDARI : un système intelligent distribué appliqué aux réseaux informatiques

    OpenAIRE

    Oumtanaga, S.

    1996-01-01

    Cet article présente le projet SIDARI, un système intelligent distribué appliqué aux réseaux informatiques. Après avoir exposé les besoins et les contraintes en formation des réseaux informatiques, nous proposons une solution issue des techniques de l'intelligence artificielle, de l'approche orientée objets, et des tuteurs intelligents. (Résumé d'auteur)

  18. Measurement of the transverse diffusion and Townsend's first ionisation coefficients from the observation of the photon flux produced in a Townsend discharge in molecular hydrogen

    International Nuclear Information System (INIS)

    The method used to obtain the transport parameters of a Townsend discharge reported by Blevin et al. (J. Phys. D.; 9:1671, 471 and 465 (1976)) from the observation of the photon flux produced in the discharge has been extended to enable measurements of the transverse diffusion coefficient and Townsend's first ionisation to be made. The results obtained in molecular hydrogen are reported in this paper. (author)

  19. Occupational exposure to ionising radiation 1990-1996. Analysis of doses reported to the Health and Safety Executive's Central Index of Dose Information

    International Nuclear Information System (INIS)

    The Central Index of Dose Information (CIDI) is the Health and Safety Executive's (HSE's) national database of occupational exposure to ionising radiation. It is operated under contract by the National Radiological Protection Board (NRPB). CIDI receives annually, from Approved Dosimetry Services (ADS) summaries of radiation doses recorded for employees designated as classified persons in the United Kingdom. This is the second analysis of dose summary information to be published. (author)

  20. Rapid analysis of formic acid, acetic acid, and furfural in pretreated wheat straw hydrolysates and ethanol in a bioethanol fermentation using atmospheric pressure chemical ionisation mass spectrometry

    Directory of Open Access Journals (Sweden)

    Smart Katherine A

    2011-09-01

    Full Text Available Abstract Atmospheric pressure chemical ionisation mass spectrometry (APCI-MS offers advantages as a rapid analytical technique for the quantification of three biomass degradation products (acetic acid, formic acid and furfural within pretreated wheat straw hydrolysates and the analysis of ethanol during fermentation. The data we obtained using APCI-MS correlated significantly with high-performance liquid chromatography analysis whilst offering the analyst minimal sample preparation and faster sample throughput.

  1. Shoot-supplied ammonium targets the root auxin influx carrier AUX1 and inhibits lateral root emergence in Arabidopsis

    KAUST Repository

    Li, Baohai

    2011-03-24

    Deposition of ammonium (NH4 +) from the atmosphere is a substantial environmental problem. While toxicity resulting from root exposure to NH4 + is well studied, little is known about how shoot-supplied ammonium (SSA) affects root growth. In this study, we show that SSA significantly affects lateral root (LR) development. We show that SSA inhibits lateral root primordium (LRP) emergence, but not LRP initiation, resulting in significantly impaired LR number. We show that the inhibition is independent of abscisic acid (ABA) signalling and sucrose uptake in shoots but relates to the auxin response in roots. Expression analyses of an auxin-responsive reporter, DR5:GUS, and direct assays of auxin transport demonstrated that SSA inhibits root acropetal (rootward) auxin transport while not affecting basipetal (shootward) transport or auxin sensitivity of root cells. Mutant analyses indicated that the auxin influx carrier AUX1, but not the auxin efflux carriers PIN-FORMED (PIN)1 or PIN2, is required for this inhibition of LRP emergence and the observed auxin response. We found that AUX1 expression was modulated by SSA in vascular tissues rather than LR cap cells in roots. Taken together, our results suggest that SSA inhibits LRP emergence in Arabidopsis by interfering with AUX1-dependent auxin transport from shoot to root. © 2011 Blackwell Publishing Ltd.

  2. Periodicity, Electronic Structures, and Bonding of Gold Tetrahalides [AuX4]- (X = F, Cl, Br, I, At, Uus).

    Science.gov (United States)

    Li, Wan-Lu; Li, Yong; Xu, Cong-Qiao; Wang, Xue-Bin; Vorpagel, Erich; Li, Jun

    2015-12-01

    Systematic theoretical and experimental investigations have been performed to understand the periodicity, electronic structures, and bonding of gold halides using tetrahalide [AuX4](-) anions (X = F, Cl, Br, I, At, Uus). The [AuX4](-) (X = Cl, Br, I) anions were experimentally produced in the gas phase, and their negative-ion photoelectron spectra were obtained, exhibiting rich and well-resolved spectral peaks. As expected, Au-X bonds in such series contain generally increasing covalency when halogen ligands become heavier. We calculated the adiabatic electron detachment energies as well as vertical electron detachment energies using density functional theory methods with scalar relativistic and spin-orbit coupling effects. The computationally simulated photoelectron spectra are in good agreement with the experimental ones. Our results show that the trivalent Au(III) oxidation state becomes progressively less stable while Au(I) tends to be preferred when the halides become heavier along the Periodic Table. This series of molecules provides an example for manipulating the oxidation state of metals in complexes through ligand design. PMID:26550845

  3. Proposition d'attribution de deux contrats pour la fourniture de fils supraconducteurs destines aux aimants de correction du LHC

    CERN Document Server

    1999-01-01

    Le présent document concerne l'attribution de deux contrats pour la fourniture de fils supraconducteurs émaillés de quatre types différents (fil 1, fil 2, fil 3 et fil 4) destinés aux aimants de correction du LHC. Un appel d'offres (IT-2649/LHC/LHC) a été adressé le 13 juillet 1999 à quatre entreprises dans quatre Etats membres, trois entreprises au Japon et trois entreprises aux Etats-Unis. A la date de clôture, le CERN avait reçu cinq offres. Il est demandé au Comité des finances d'approuver la négociation de deux contrats: 1. d'une part avec IGC (USA) pour la fourniture de fils supraconducteurs 1 et 2 destinés aux aimants de correction du LHC pour un prix total net de 996 074 dollars des Etats-Unis, non révisable, avec une option pour la fourniture de fils 1 et 2 supplémentaires représentant 20% de la quantité initiale pour un prix total net de 199 215 dollars des Etats-Unis, révisable, ce qui porte le montant total à 1 195 289 dollars US, révisable pour l'option. Au taux de change in...

  4. Phloem-Mobile Aux/IAA Transcripts Target to the Root Tip and Modify Root Architecture

    Institute of Scientific and Technical Information of China (English)

    Michitaka Notaguchi; Shmuel Wolf; William J. Lucas

    2012-01-01

    In plants,the phloem is the component of the vascular system that delivers nutrients and transmits signals from mature leaves to developing sink tissues.Recent studies have identified proteins,mRNA,and small RNA within the phloem sap of several plant species.It is now of considerable interest to elucidate the biological functions of these potential long-distance signal agents,to further our understanding of how plants coordinate their developmental programs at the whole-plant level.In this study,we developed a strategy for the functional analysis of phloem-mobile mRNA by focusing on IAA transcripts,whose mobility has previously been reported in melon (Cucumis melo cv.Hale's Best Jumbo).Indoleacetic acid (IAA) proteins are key transcriptional regulators of auxin signaling,and are involved in a broad range of developmental processes including root development.We used a combination of vasculature-enriched sampling and hetero-grafting techniques to identify IAA18 and IAA28 as phloemmobile transcripts in the model plant Arabidopsis thaliana.Micro-grafting experiments were used to confirm that these IAA transcripts,which are generated in vascular tissues of mature leaves,are then transported into the root system where they negatively regulate lateral root formation.Based on these findings,we present a model in which auxin distribution,in combination with phloem-mobile AuxIIAA transcripts,can determine the sites of auxin action.

  5. Cours Sécurité : Sensibilisation aux gestes et postures de travail

    CERN Multimedia

    DGS Unit

    2010-01-01

    Prochaine session le 21 octobre 2010. 12 places disponibles. Ce cours concerne toutes les personnes appelées à réaliser des manutentions manuelles dans le cadre de leurs activités. Contenu du cours : Théorie - Présentation des objectifs du programme ; - L'accident du travail (définition, coûts) ; - Statistiques CNAM ; - Notion d'anatomie (mécanique humaine) ; - Les différentes pathologies (lumbago, sciatique, hernie discale) ; - Discussion sur les problèmes particuliers rencontrés dans la vie courante. Pratique - Les efforts mécaniques sur la colonne dus aux mauvaises postures ; - Les principes de base de l'utilisation de la mécanique humaine ; - Exercices pratiques d'application (sur objets divers standards) ; - Prises de vues au caméscope des positions de chacun. Pour vous inscrire : https://edh.cern.ch/Document/Personnel/TRN?new=YES&...

  6. Application of solar chargers to prospection instruments; Application des chargeurs solaires aux appareils de prospection

    Energy Technology Data Exchange (ETDEWEB)

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

    1960-07-01

    The use of conventional batteries has certain disadvantages, and for this reason high-voltage batteries have been gradually replaced in all prospection instruments by transistor supply systems, using less cumbersome sources of energy. All the same low voltages are still necessary, and in hot or damp countries the use of these batteries leads to consumptions out of all proportion to the services rendered. This is why the use of solar energy possesses real advantages. After a brief review of the basic ideas on semiconductors, this article describes a selenium solar battery which was developed by the Westinghouse brakes and signals society. (author) [French] L'utilisation de piles classiques presente certains inconvenients. C'est pourquoi, dans tous les appareils de prospection, les piles fournissant des tensions elevees ont ete remplacees au fur et a mesure par des alimentations a base de transistors, utilisant des sources d'energie moins encombrantes. Toutefois, il faut tout de meme avoir des tensions faibles et l'utilisation de ces piles entraine dans les pays chauds ou humides une consommation disproportionnee par rapport aux services rendus. C'est pourquoi l'emploi de l'energie solaire presente de reels avantages. Cet expose decrit, apres un rappel de notion de base sur les semi-conducteurs, une batterie solaire a base de selenium qui a ete realisee par la Societe des freins et signaux Westinghouse. (auteur)

  7. Risks of low dose ionising radiation exposures Riesgos derivados de la exposición a dosis bajas de radiación ionizante

    Directory of Open Access Journals (Sweden)

    Almudena Real Gallego

    2010-12-01

    Full Text Available Although ionising radiation has been shown to have several beneficial applications for humans, it can also produce detrimental effects in humans and the environment. To adequately protect man and environment from the potential harmful effects of ionising radiation, is essential to know in detail the biological effects produced by it, its characteristics and the various factors that influence these effects. That is the objective of this article, describe the current status of knowledge about biological effects induced by ionising radiation, with special emphasis on those effects occurring after low dose exposures.La radiación ionizante ha mostrado tener diversas aplicaciones beneficiosas para el hombre, pero también puede dañar la salud de las personas y el medio ambiente. Para proteger adecuadamente al hombre de los posibles efectos nocivos de la radiación ionizante es imprescindible conocer en detalle los efectos biológicos producidos por esta, sus características y los distintos factores que influyen en dichos efectos. Ese es el objetivo de este artículo: describir el estado actual del conocimiento sobre los efectos biológicos que puede producir la radiación ionizante, con especial énfasis en aquellos efectos que se producen tras la exposición a dosis bajas.

  8. Collection of legislative and regulatory arrangements relative to radiation protection. Part 1: laws and decrees of the Public Health Code and Labour Code concerning the protection of populations, patients and workers against the risks of ionizing radiations; Recueil des dispositions legislatives et reglementaires relatives a la radioprotection. Partie 1: lois et decrets du code de la sante publique et du code du travail concernant la protection de la population, des patients et des travailleurs contre les dangers des rayonnements ionisants

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-05-15

    This collection concerns on one hand the protection of the population and on the other hand the protection of the workers against ionizing radiations. As regards the protection of the populations, there is a quality control of waters, a control of the medical devices for the protection of patients. For the protection of the workers it is the employment law which serves as reference. (N.C.)

  9. Collection of regulatory texts relative to radiation protection. Part 2: orders and decisions taken in application of the Public Health Code and Labour Code concerning the protection of populations, patients and workers against the risks of ionizing radiations; Recueil de textes reglementaires relatifs a la radioprotection. Partie 2: arretes et decisions pris en application du Code de Sante Publique et du Code du Travail concernant la protection de la population, des patients et des travailleurs contre les dangers des rayonnements ionisants

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-05-15

    This collection of texts includes the general measures of population protection, exposure to natural radiations, general system of authorizations and statements, protection of persons exposed to ionizing radiations for medical purpose, situations of radiological emergency and long exposure to ionizing radiations, penal dispositions, application of the Public Health code and application of the Labour code. Chronological contents by date of publication is given. (N.C.)

  10. Effects of low-dose ionising radiation on pituitary adenoma: is there a role for L-type calcium channel?

    Energy Technology Data Exchange (ETDEWEB)

    Soares, Marcella Araugio; Santos, Raquel Gouvea dos [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN), Belo Horizonte, MG (Brazil). Lab. de Radiobiologia]. E-mail: santosr@cdtn.br

    2005-10-15

    Pituitary adenomas constitute about 6-18% of brain tumours in adults. Activation of voltage gated calcium currents can account for growth hormone over secretion in some GH-secreting pituitary adenomas that produce an acromegaly appearance and increase mortality. Ca{sup 2+} ions, as mediators of intracellular signalling, are crucial for the development of apoptosis. However, the role of [Ca{sup 2+}] in the development of apoptosis is ambiguous. In this study, the effects of low-dose ionising gamma radiation ({sup 60} Co) on rat pituitary adenoma cells survival and proliferation and the role of calcium channels on the apoptosis radio-induced were evaluated. Doses as low as 3 Gy were found to inhibit GH3 cell proliferation. Even though there was a significant number of live cells,168 hours following irradiation, they were not able to proliferate. The results indicate that the blockade of extracellular calcium influx through these channels does not interfere in the radiation-induced apoptosis in GH3 cells. (author)

  11. Effect of ionising radiation on polyphenolic content and antioxidant potential of parathion-treated sage (Salvia officinalis) leaves.

    Science.gov (United States)

    Ben Salem, Issam; Fekih, Sana; Sghaier, Haitham; Bousselmi, Mehrez; Saidi, Mouldi; Landoulsi, Ahmed; Fattouch, Sami

    2013-11-15

    The γ-irradiation effects on polyphenolic content and antioxidant capacity of parathion-pretreated leaves of Salvia officinalis plant were investigated. The analysis of phenolic extracts of sage without parathion showed that irradiation decreased polyphenolic content significantly (p<0.05) by 30% and 45% at 2 and 4kGy, respectively, compared to non-irradiated samples. The same trend was observed for the Trolox equivalent antioxidant capacity (TEAC), as assessed by the anionic DPPH and cationic ABTS radical-scavenging assays. The antioxidant potential decreased significantly (p<0.01) at 2 and 4kGy, by 11-20% and 40-44%, respectively. The results obtained with a pure chlorogenic acid solution confirmed the degradation of phenols; however, its TEAC was significantly (p<0.01) increased following irradiation. Degradation products of parathion formed by irradiation seem to protect against a decline of antioxidant capacity and reduce polyphenolic loss. Ionising radiation was found to be useful in breaking down pesticide residues without inducing significant losses in polyphenols.

  12. Evaluation of ion chamber dependent correction factors for ionisation chamber dosimetry in proton beams using a Monte Carlo method

    Energy Technology Data Exchange (ETDEWEB)

    Palmans, H. [Ghent Univ. (Belgium). Dept. of Biomedical Physics; Verhaegen, F.

    1995-12-01

    In the last decade, several clinical proton beam therapy facilities have been developed. To satisfy the demand for uniformity in clinical (routine) proton beam dosimetry two dosimetry protocols (ECHED and AAPM) have been published. Both protocols neglect the influence of ion chamber dependent parameters on dose determination in proton beams because of the scatter properties of these beams, although the problem has not been studied thoroughly yet. A comparison between water calorimetry and ionisation chamber dosimetry showed a discrepancy of 2.6% between the former method and ionometry following the ECHED protocol. Possibly, a small part of this difference can be attributed to chamber dependent correction factors. Indications for this possibility are found in ionometry measurements. To allow the simulation of complex geometries with different media necessary for the study of those corrections, an existing proton Monte Carlo code (PTRAN, Berger) has been modified. The original code, that applies Mollire`s multiple scattering theory and Vavilov`s energy straggling theory, calculates depth dose profiles, energy distributions and radial distributions for pencil beams in water. Comparisons with measurements and calculations reported in the literature are done to test the program`s accuracy. Preliminary results of the influence of chamber design and chamber materials on dose to water determination are presented.

  13. For the development of therapy with ionising radiation in tooth, mouth and jaw medicine. An historical summary

    International Nuclear Information System (INIS)

    Based on the corresponding literature study, the development of therapy with ionising radiation, especially in the areas of tooth, mouth and jaw medicine, is reported from the discovery of X-rays up till the present. First from 1915 on did the X-ray antiphlogistic irradiation with in importance, from 1925 to about 1940 it played a domineering role, after the war was hardly still in use and since 1970 is considered in the stomatological sector obsolete. In comparison, already in 1905 there were individual successes in tumor therapy using X radiation. After many failures and competition with the method of radium therapy in the following years, a new upswing in X-radiation came starting in around 1930 with the introduction of the Chaoul contact therapy. The high point of this development is the introduction of supervolt therapy starting around 1965. It is the result of comprehensive research in the area of radiation physics. As a result of further developed techniques there were soon combined and competing procedures available, whose results, however, have not been adequately compared and documented. From 1970 on electronic data processing has primarily taken over individual irradiation planning (cobalt 60 and electron irradiation), predictions about clinically relevant therapy successes are not present at this time. (TRV)

  14. The formation and evolution of reconnection-driven slow-mode shocks in a partially ionised plasma

    CERN Document Server

    Hillier, Andrew; Nakamura, Naoki

    2016-01-01

    The role of slow-mode MHD shocks in magnetic reconnection is one of great importance for energy conversion and transport, but in many astrophysical plasmas the plasma is not fully ionised. In this paper, we investigate, using numerical simulations, the role of collisional coupling between a proton-electron charge-neutral fluid and a neutral hydrogen fluid for the 1D Riemann problem initiated in a constant pressure and density background state by a discontinuity in the magnetic field. This system, in the MHD limit, is characterised by two waves: a fast-mode rarefaction wave that drives a flow towards a slow-mode MHD shock. The system evolves through four stage: initiation, weak coupling, intermediate coupling and a quasi steady state. The initial stages are characterised by an over-pressured neutral region that expands with characteristics of a blast wave. In the later stages, the system tends towards a self-similar solution where the main drift velocity is concentrated in the thin region of the shock front. D...

  15. Analysis of wax ester molecular species by high performance liquid chromatography/atmospheric pressure chemical ionisation mass spectrometry.

    Science.gov (United States)

    Vrkoslav, Vladimír; Urbanová, Klára; Cvacka, Josef

    2010-06-18

    High chromatographic resolution of wax esters (WEs) was achieved by non-aqueous reversed-phase liquid chromatography on a Nova-Pak C18 column by optimising the acetonitrile/ethyl acetate mobile phase gradient. The retention behaviour of WEs was studied in this chromatographic system. The WEs eluted according to their equivalent carbon number (ECN) values; within the group of WEs with the identical ECN, the most unsaturated species tended to elute first. The isobaric WEs with different positions of the ester moiety were separated from each other whenever the lengths of the chains were sufficiently different. The methyl-branched esters eluted at shorter retention times than the straight-chained analogues, and the resolution among methyl-branched WEs depended on the position of the branching. The analytes were detected by atmospheric pressure chemical ionisation mass spectrometry (APCI-MS) using data-dependent scanning. WEs provided simple full-scan spectra with abundant protonated molecules and low-intensity fragments. Collision-induced dissociation (CID) promoted identification of the WE molecular species. The responses of WEs were found to be dependent on the number of double bonds and on the alkyl-chain length; the limits of the detection ranged from 20micromol/L to 200nmol/L. The HPLC/APCI-MS was applied for the analysis of the WEs isolated from honeycomb beeswax, jojoba oil and human hair. Good agreement between reported results and the literature data was achieved, with several novel polyunsaturated WEs also being found.

  16. Resolving Ionisation and Metallicity on Parsec Scales Across Mrk 71 (NGC2363) with HST-WFC3

    CERN Document Server

    James, Bethan L; Aloisi, Alessandra; Calzetti, Daniela; Kewley, Lisa

    2015-01-01

    Blue Compact Dwarf (BCD) Galaxies in the nearby Universe provide a means for studying feedback mechanisms and star-formation processes in low-metallicity environments in great detail. Due to their vicinity, these local analogues to young galaxies are well suited for high-resolution studies that would be unfeasible for primordial galaxies in the high-redshift universe. Here we present HST-WFC3 observations of one such BCD, Mrk 71 (NGC 2363), one of the most powerful local starbursts known, in the light of [O II], He II, Hb, [O III], Ha, and [S II]. At D=3.44 Mpc, this extensive suite of emission line images enables us to explore the chemical and physical conditions of Mrk 71 on ~2 pc scales. Using these high spatial-resolution observations, we use emission line diagnostics to distinguish ionisation mechanisms on a pixel-by-pixel basis and show that despite the previously reported hypersonic gas and super-bubble blow out, the gas in Mrk 71 is photoionised, with no sign of shock-excited emission. Using strong-li...

  17. The Suzaku view of highly-ionised outflows in AGN: I - Statistical detection and global absorber properties

    CERN Document Server

    Gofford, Jason; Tombesi, Francesco; Braito, Valentina; Turner, T Jane; Miller, Lance; Cappi, Massimo

    2012-01-01

    We present the results of a new spectroscopic study of Fe K-band absorption in Active Galactic Nuclei (AGN). Using data obtained from the Suzaku public archive we have performed a statistically driven blind search for Fe XXV Hea and/or Fe XXVI Lyb absorption lines in a large sample of 51 type 1.0-1.9 AGN. Through extensive Monte Carlo simulations we find statistically significant absorption is detected at E>6.7 keV in 20/51 sources at the P(MC)>95% level, which corresponds to ~40% of the total sample. In all cases, individual absorption lines are detected independently and simultaneously amongst the two (or three) available XIS detectors which confirms the robustness of the line detections. The most frequently observed outflow phenomenology consists of two discrete absorption troughs corresponding to Fe XXV Hea and Fe XXVI Lyb at a common velocity shift. From xstar fitting the mean column density and ionisation parameter for the Fe K absorption components are log(NH/cm^{-2})~23 and log(xi/erg cm s^{-1})~4.5, ...

  18. Characterisation of a proposed internet synthesis of N,N-dimethyltryptamine using liquid chromatography/electrospray ionisation tandem mass spectrometry.

    Science.gov (United States)

    Martins, Cláudia P B; Freeman, Sally; Alder, John F; Brandt, Simon D

    2009-08-14

    The psychoactive properties of N,N-dimethyltryptamine (DMT) are known to induce altered states of consciousness in humans. These properties attract great interest from clinical, neuroscientific, clandestine and forensic communities. The Breath of Hope Synthesis was reported on an internet website as a convenient two-step methodology for the preparation of DMT. The analytical characterisation of the first stage was the subject of previous publications by the authors and involved the thermal decarboxylation of tryptophan and the formation of tryptamine. The present study reports on the characterisation of the second step of this procedure which was based on the methylation of tryptamine. This employed methyl iodide and benzyltriethylammonium chloride/sodium hydroxide as a phase transfer catalyst. The reaction product was characterised by liquid chromatography/electrospray ionisation tandem mass spectrometry and orthogonal acceleration time-of-flight mass spectrometry. Quantitative evaluation was carried out in positive multiple reaction monitoring mode (MRM), which included synthesis of the identified reaction products. MRM screening of the product did not lead to the detection of DMT. Instead, 11.1% tryptamine starting material, 21.0% N,N,N-trimethyltryptammonium iodide (TMT) and 47.4% 1-N-methyl-TMT were detected. A 0.5% trace of the monomethylated N-methyltryptamine was also detected. This study demonstrated the impact on product purity of doubtful synthetic methodologies discussed on the internet. PMID:19592003

  19. The Suzaku view of highly-ionised outflows in AGN: II -- Location, energetics and scalings with Bolometric Luminosity

    CERN Document Server

    Gofford, J; McLaughlin, D E; Braito, V; Turner, T J; Tombesi, F; Cappi, M

    2015-01-01

    Ongoing studies with XMM-Newton have shown that powerful accretion disc winds, as revealed through highly-ionised Fe\\,K-shell absorption at E>=6.7 keV, are present in a significant fraction of Active Galactic Nuclei (AGN) in the local Universe (Tombesi et al. 2010). In Gofford et al. (2013) we analysed a sample of 51 Suzaku-observed AGN and independently detected Fe K absorption in ~40% of the sample, and we measured the properties of the absorbing gas. In this work we build upon these results to consider the properties of the associated wind. On average, the fast winds (v_out>0.01c) are located ~10^{15-18} cm (typically ~10^{2-4} r_s) from their black hole, their mass outflow rates are of the order ~0.01-1 Msun/yr or ~(0.01-1) M_edd and kinetic power is constrained to ~10^{43-45} erg/s, equivalent to ~(0.1-10%) L_edd. We find a fundamental correlation between the source bolometric luminosity and the wind velocity, with v_out \\propto L_bol^{\\alpha} and \\alpha=0.4^{+0.3}_{-0.2}$ (90% confidence), which indica...

  20. Rapid assignment of malting barley varieties by matrix-assisted laser desorption-ionisation - Time-of-flight mass spectrometry.

    Science.gov (United States)

    Šedo, Ondrej; Kořán, Michal; Jakešová, Michaela; Mikulíková, Renata; Boháč, Michal; Zdráhal, Zbyněk

    2016-09-01

    A method for discriminating malting barley varieties based on direct matrix-assisted laser desorption-ionisation - time-of-flight mass spectrometry (MALDI-TOF MS) fingerprinting of proteins was developed. Signals corresponding to hordeins were obtained by simple mixing of powdered barley grain with a MALDI matrix solution containing 12.5mgmL(-1) of ferulic acid in an acetonitrile:water:formic acid 50:33:17 v/v/v mixture. Compared to previous attempts at MALDI-TOF mass spectrometric analysis of barley proteins, the extraction and fractionation steps were practically omitted, resulting in a significant reduction in analytical time and costs. The discriminatory power was examined on twenty malting barley varieties and the practicability of the method was tested on sixty barley samples acquired from Pilsner Urquell Brewery. The method is proposed as a rapid tool for variety assignment and purity determination of malting barley that may replace gel electrophoresis currently used for this purpose. PMID:27041307

  1. Chronic low-dose-rate ionising radiation affects the hippocampal phosphoproteome in the ApoE−/− Alzheimer mouse model

    DEFF Research Database (Denmark)

    Kempf, Stefan; Janik, Dirk; Barjaktarovic, Zarko;

    2016-01-01

    Accruing data indicate that radiation-induced consequences resemble pathologies of neurodegenerative diseases such as Alzheimer´s. The aim of this study was to elucidate the effect on hippocampus of chronic low-dose-rate radiation exposure (1 mGy/day or 20 mGy/day) given over 300 days with cumula......Accruing data indicate that radiation-induced consequences resemble pathologies of neurodegenerative diseases such as Alzheimer´s. The aim of this study was to elucidate the effect on hippocampus of chronic low-dose-rate radiation exposure (1 mGy/day or 20 mGy/day) given over 300 days...... with cumulative doses of 0.3 Gy and 6.0 Gy, respectively. ApoE deficient mutant C57Bl/6 mouse was used as an Alzheimer´s model. Using mass spectrometry, a marked alteration in the phosphoproteome was found at both dose rates. The radiation-induced changes in the phosphoproteome were associated with the control...... that several molecular targets induced by chronic low-dose-rate radiation overlap with those of Alzheimer´s pathology. It may suggest that ionising radiation functions as a contributing risk factor to this neurodegenerative disease....

  2. Evaluation of ion chamber dependent correction factors for ionisation chamber dosimetry in proton beams using a Monte Carlo method

    International Nuclear Information System (INIS)

    In the last decade, several clinical proton beam therapy facilities have been developed. To satisfy the demand for uniformity in clinical (routine) proton beam dosimetry two dosimetry protocols (ECHED and AAPM) have been published. Both protocols neglect the influence of ion chamber dependent parameters on dose determination in proton beams because of the scatter properties of these beams, although the problem has not been studied thoroughly yet. A comparison between water calorimetry and ionisation chamber dosimetry showed a discrepancy of 2.6% between the former method and ionometry following the ECHED protocol. Possibly, a small part of this difference can be attributed to chamber dependent correction factors. Indications for this possibility are found in ionometry measurements. To allow the simulation of complex geometries with different media necessary for the study of those corrections, an existing proton Monte Carlo code (PTRAN, Berger) has been modified. The original code, that applies Mollire's multiple scattering theory and Vavilov's energy straggling theory, calculates depth dose profiles, energy distributions and radial distributions for pencil beams in water. Comparisons with measurements and calculations reported in the literature are done to test the program's accuracy. Preliminary results of the influence of chamber design and chamber materials on dose to water determination are presented

  3. Determination of agrochemical compounds in soya plants by imaging matrix-assisted laser desorption/ionisation mass spectrometry.

    Science.gov (United States)

    Mullen, Alexander K; Clench, Malcolm R; Crosland, Susan; Sharples, Kate R

    2005-01-01

    Detection and imaging of the herbicide mesotrione (2-(4-mesyl-2-nitrobenzoyl)cyclohexane-1,3-dione) and the fungicide azoxystrobin (methyl (E)-2-{2-[6-(2-cyanophenoxy)pyrimidin-4-yloxy]phenyl}-3-methoxyacrylate), on the surface of the soya leaf, and the detection and imaging of azoxystrobin inside the stem of the soya plant, have been achieved using matrix-assisted laser desorption/ionisation quadrupole time-of-flight mass spectrometry. In leaf analysis experiments, the two pesticides were deposited onto the surface of individual soya leaves on growing plants. The soya leaves were removed and prepared for direct and indirect (following blotting onto matrix-coated cellulose membranes) imaging analysis at different periods after initial pesticide application. In stem analysis experiments, azoxystrobin was added to the nutrient solution of a soya plant growing in a hydroponics system. The plant was left for 48 h, and then horizontal and vertical stem sections were prepared for direct imaging analysis. The images obtained demonstrate the applicability of MALDI imaging to the detection and imaging of small organic compounds in plant tissue and further extend the analytical repertoire of the versatile MALDI technique. PMID:16106343

  4. Desorption electrospray ionisation mass spectrometry: A rapid screening tool for veterinary drug preparations and forensic samples from hormone crime investigations

    International Nuclear Information System (INIS)

    Hormone and veterinary drug screening and forensics can benefit from the recent developments in desorption electrospray ionisation (DESI) mass spectrometry (MS). In this work the feasibility of DESI application has been studied. Using a linear ion trap or quadrupole time-of-flight (TOF) MS instrument both full-scan and data-dependent collision-induced dissociation MSn spectra were acquired in seconds without sample preparation. Preliminary data are presented for the rapid screening of (pro)hormone supplement samples, an illegal steroid cocktail and forensic samples from veterinary drug investigations. The potential of this DESI approach is clearly demonstrated since compounds observed could be independently confirmed by liquid chromatography/TOFMS with accurate mass measurement, and/or proton nuclear magnetic resonance spectroscopy. Specific concerns related to false-positive and false-negative findings due to limitations in quantification and memory-effects are briefly discussed. It is envisaged that DESI will achieve a prominent role in hormone and veterinary drug analysis in the near future

  5. Expression of wild-type PtrIAA14.1, a poplar Aux/IAA gene causes morphological changes in Arabidopsis

    Directory of Open Access Journals (Sweden)

    Shanda eLiu

    2015-06-01

    Full Text Available Aux/IAA proteins are transcriptional repressors that control auxin signaling by interacting with Auxin Response Factors (ARFs. So far all of the identified Aux/IAA mutants with auxin-related phenotypes in Arabidopsis and rice (Oryza sativa are dominant gain-of-function mutants, with mutantions in Domain II that affected stability of the corresponding Aux/IAA proteins. On the other hand, morphological changes were observed in knock-down mutants of Aux/IAA genes in tomato (Solanum lycopersicum, suggesting that functions of Aux/IAA proteins may be specific for certain plant species. We report here the characterization of PtrIAA14.1, a poplar (Populus trichocarpa homologue of IAA7. Bioinformatics analysis showed that PtrIAA14.1 is a classic Aux/IAA protein. It contains four conserved domains with the repressor motif in Domain I, the degron in Domain II, and the conserved amino acid signatures for protein-protein interactions in Domain III and Domain IV. Protoplast transfection assays showed that PtrIAA14.1 is localized in nucleus. It is unable in the presence of auxin, and it represses auxin response reporter gene expression. Expression of wild type PtrIAA14.1 in Arabidopsis resulted in auxin-related phenotypes including down-curling leaves, semi-draft with increased number of branches, and greatly reduced fertility, but expression of the Arabidopsis Aux/IAA genes tested remain largely unchanged in the transgenic plants. Protein-protein interaction assays in yeast and protoplasts showed that PtrIAA14.1 interacted with ARF5, but not other ARFs. Consistent with this observation, vascular patterning was altered in the transgenic plants, and the expression of AtHB8 (Arabidopsis thaliana Homeobox Gene 8 was reduced in transgenic plants.

  6. Radiation in the workplace-a review of studies of the risks of occupational exposure to ionising radiation

    Energy Technology Data Exchange (ETDEWEB)

    Wakeford, Richard [Dalton Nuclear Institute, The University of Manchester, Pariser Building-G Floor, PO Box 88, Sackville Street, Manchester M60 1QD (United Kingdom)], E-mail: Richard.Wakeford@manchester.ac.uk

    2009-06-01

    Many individuals are, or have been, exposed to ionising radiation in the course of their work and the epidemiological study of occupationally irradiated groups offers an important opportunity to complement the estimates of risks to health resulting from exposure to radiation that are obtained from other populations, such as the Japanese survivors of the atomic bombings of Hiroshima and Nagasaki in 1945. Moreover, workplace exposure to radiation usually involves irradiation conditions that are of direct relevance to the principal concern of radiological protection: protracted exposure to low level radiation. Further, some workers have been exposed to radioactive material that has been inadvertently taken into the body, and the study of these groups leads to risk estimates derived directly from the experience of those irradiated by these 'internal emitters', intakes of {alpha}-particle-emitters being of particular interest. Workforces that have been the subject of epidemiological study include medical staff, aircrews, radium dial luminisers, underground hard-rock miners, Chernobyl clean-up workers, nuclear weapons test participants and nuclear industry workers. The first solid epidemiological evidence of the stochastic effects of irradiation came from a study of occupational exposure to medical x-rays that was reported in 1944, which demonstrated a large excess risk of leukaemia among US radiologists; but the general lack of dose records for early medical staff who tended to experience the highest exposures hampers the derivation of risks per unit dose received by medical workers. The instrument dial luminisers who inadvertently ingested large amounts of radium-based paint and underground hard-rock miners who inhaled large quantities of radon and its decay products suffered markedly raised excess risks of, respectively, bone and lung cancers; the miner studies have provided standard risk estimates for radon-induced lung cancer. The large numbers of nuclear

  7. Radiation in the workplace-a review of studies of the risks of occupational exposure to ionising radiation.

    Science.gov (United States)

    Wakeford, Richard

    2009-06-01

    Many individuals are, or have been, exposed to ionising radiation in the course of their work and the epidemiological study of occupationally irradiated groups offers an important opportunity to complement the estimates of risks to health resulting from exposure to radiation that are obtained from other populations, such as the Japanese survivors of the atomic bombings of Hiroshima and Nagasaki in 1945. Moreover, workplace exposure to radiation usually involves irradiation conditions that are of direct relevance to the principal concern of radiological protection: protracted exposure to low level radiation. Further, some workers have been exposed to radioactive material that has been inadvertently taken into the body, and the study of these groups leads to risk estimates derived directly from the experience of those irradiated by these 'internal emitters', intakes of alpha-particle-emitters being of particular interest. Workforces that have been the subject of epidemiological study include medical staff, aircrews, radium dial luminisers, underground hard-rock miners, Chernobyl clean-up workers, nuclear weapons test participants and nuclear industry workers. The first solid epidemiological evidence of the stochastic effects of irradiation came from a study of occupational exposure to medical x-rays that was reported in 1944, which demonstrated a large excess risk of leukaemia among US radiologists; but the general lack of dose records for early medical staff who tended to experience the highest exposures hampers the derivation of risks per unit dose received by medical workers. The instrument dial luminisers who inadvertently ingested large amounts of radium-based paint and underground hard-rock miners who inhaled large quantities of radon and its decay products suffered markedly raised excess risks of, respectively, bone and lung cancers; the miner studies have provided standard risk estimates for radon-induced lung cancer. The large numbers of nuclear industry

  8. Differentiation of Lard from Other Edible Fats by Gas Chromatography-Flame Ionisation Detector (GC-FID and Chemometrics

    Directory of Open Access Journals (Sweden)

    Omar Dahimi

    2014-01-01

    Full Text Available The presence of lard or its derivatives in any food products is a serious religious issue among Muslim and Judaism. Thus, the objective of this study was to investigate the use of gas chromatography with flame ionisation detector (GC-FID coupled with chemometrics techniques such as Principle Components Analysis (PCA and K-mean cluster analysis to differentiate lard adulteration at very low concentrations in beef and chicken fats. The measurements were made from the pure lard, beef tallow, pure chicken fat; and beef tallow (BT, chicken fat (CF adulterated with different concentrations of lard (0.5%-10% in BT and CF. The data were first scaled into standardisation before PCA is performed to each of the scaled data using Unscrambler software. The Scores plots and loadings plots of each scaled data were compared and studied. The results showed that lard contains higher fatty acid (FA of C18: 2cis and low C16:0 FA, but oppositely for beef tallow and chicken fat. The amount of C4:0, C14:0, and C18:0 FAs are approximately similar for all fats. Others FAs are small in amount and nearly similar for both. Additionally, PCA was able to significantly identify lard, beef fat, chicken fat and the mixtures of lard and beef tallow, lard and chicken fat, even at lower concentration level (0.5 % lard-99.5% beef tallow / chicken fat (w/w. K-mean cluster only able to classify the pure lard (LD, pure chicken fat (CF and pure beef tallow (BT

  9. The long-term effects of acute exposure to ionising radiation on survival and fertility in Daphnia magna.

    Science.gov (United States)

    Sarapultseva, Elena I; Dubrova, Yuri E

    2016-10-01

    The results of recent studies have provided strong evidence for the transgenerational effects of parental exposure to ionising radiation and chemical mutagens. However, the transgenerational effects of parental exposure on survival and fertility remain poorly understood. To establish whether parental irradiation can affect the survival and fertility of directly exposed organisms and their offspring, crustacean Daphnia magna were given 10, 100, 1000 and 10,000mGy of acute γ-rays. Exposure to 1000 and 10,000mGy significantly compromised the viability of irradiated Daphnia and their first-generation progeny, but did not affect the second-generation progeny. The fertility of F0 and F1Daphnia gradually declined with the dose of parental exposure and significantly decreased at dose of 100mGy and at higher doses. The effects of parental irradiation on the number of broods were only observed among the F0Daphnia exposed to 1000 and 10,000mGy, whereas the brood size was equally affected in the two consecutive generations. In contrast, the F2 total fertility was compromised only among progeny of parents that received the highest dose of 10,000mGy. We propose that the decreased fertility observed among the F2 progeny of parents exposed to 10,000mGy is attributed to transgenerational effects of parental irradiation. Our results also indicate a substantial recovery of the F2 progeny of irradiated F0Daphnia exposed to the lower doses of acute γ-rays. PMID:27288911

  10. The formation and evolution of reconnection-driven, slow-mode shocks in a partially ionised plasma

    Science.gov (United States)

    Hillier, A.; Takasao, S.; Nakamura, N.

    2016-06-01

    The role of slow-mode magnetohydrodynamic (MHD) shocks in magnetic reconnection is of great importance for energy conversion and transport, but in many astrophysical plasmas the plasma is not fully ionised. In this paper, we use numerical simulations to investigate the role of collisional coupling between a proton-electron, charge-neutral fluid and a neutral hydrogen fluid for the one-dimensional (1D) Riemann problem initiated in a constant pressure and density background state by a discontinuity in the magnetic field. This system, in the MHD limit, is characterised by two waves. The first is a fast-mode rarefaction wave that drives a flow towards a slow-mode MHD shock wave. The system evolves through four stages: initiation, weak coupling, intermediate coupling, and a quasi-steady state. The initial stages are characterised by an over-pressured neutral region that expands with characteristics of a blast wave. In the later stages, the system tends towards a self-similar solution where the main drift velocity is concentrated in the thin region of the shock front. Because of the nature of the system, the neutral fluid is overpressured by the shock when compared to a purely hydrodynamic shock, which results in the neutral fluid expanding to form the shock precursor. Once it has formed, the thickness of the shock front is proportional to ξ i-1.2 , which is a smaller exponent than would be naively expected from simple scaling arguments. One interesting result is that the shock front is a continuous transition of the physical variables of subsonic velocity upstream of the shock front (a c-shock) to a sharp jump in the physical variables followed by a relaxation to the downstream values for supersonic upstream velocity (a j-shock). The frictional heating that results from the velocity drift across the shock front can amount to ~2 per cent of the reference magnetic energy.

  11. Combination of ionising irradiation and hyperthermia activates programmed apoptotic and necrotic cell death pathways in human colorectal carcinoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Mantel, Frederick; Frey, Benjamin; Haslinger, Stefan [Erlangen-Nuernberg Univ., University Hospital Erlangen (DE). Dept. of Radiation Oncology] (and others)

    2010-11-15

    The malignancy of tumor cells can be attenuated by interfering with cell death pathways. Since hyperthermia (HT) is a very potent radiosensitizer, the influence of HT (41.5 C for 1 hour) alone and in combination with ionising irradiation (X-ray; 5 Gy or 10 Gy) on the form of cell death as well as on the expression of proteins known to be major components in tumor cells' apoptotic and necrotic pathways were examined in colorectal tumor cells. The expression of proteins was analysed by western blot and the relative activity of caspases-3/7 by fluorescence- based assay. Colony formation was analysed using the clonogenic assay and cell death was determined with annexin V-FITC/propidium iodide staining. Combining X-ray with HT led to similar activation of caspase-3/7 and p53 expression in comparison to irradiation only while the amount of the pro-apoptotic proteins PUMA and Bax was increased in HCT15 and SW480 cells. HT alone or combinations with X-ray further resulted in a temporarily increased level of the anti-apoptotic protein Bcl-2. Irradiation plus HT further led to an up-regulation of IRF-5. The levels of RIP-1, a marker for programmed necrosis, increased in tumor cells which were treated with HT and/or X-ray. Combining 5 Gy irradiation with HT compared to irradiation resulted in a significantly increased number of necrotic tumor cells and in decreased colony formation. The combined treatment of colorectal tumor cells with X-ray and HT activates distinct tumor cell pathways and fosters the early appearance of a necrotic tumor cell phenotype. (orig.)

  12. Examination, characterisation and analysis techniques for the knowledge and the conservation / restoration of cultural heritage - importance of ionising radiation techniques

    International Nuclear Information System (INIS)

    For the examination, characterisation and analysis of cultural heritage artefacts or art objects and their component materials, the conservation scientist needs a palette of non destructive and non invasive techniques, in order to improve our knowledge concerning their elaboration, their evolution and/or degradation during time, and to give rational basis for their restoration and conservation. A general survey and illustrations showing the usefulness of these techniques will be presented. Among these methods, many are based on the use of ionising radiation. 1. Radiography (using X-rays, gamma rays, beta particles, secondary electrons, neutrons), electron emission radiography, tomodensimetry, 2. Scanning electron microscope associated with X-ray spectrometry, 3. X-ray diffraction, 4. Synchrotron radiation characterisation, 5. X-ray fluorescence analysis, 6. Activation analysis, 7. Ion beam analysis (PIXE, PIGE, RBS, secondary X-ray fluorescence), 8. Thermoluminescence dating, 9. Carbon-14 dating. These methods are used alone or in connection with other analytical methods. Any kind of materials can be encountered, for instance: i. stones, gems, ceramics, terracotta, enamels, glasses, i i. wood, paper, textile, bone, ivory, i i i. metals, jewellery, i v. paint layers, canvas and wooden backings, pigments, dyers, oils, binding media, varnishes, glues. Some examples will be taken, among recent work done at the Centre of Research and Restoration of the Museums of France (C2RMF), from various geographical origins, various ages and different art disciplines. This will illustrate the kind of assistance that science and technology can provide to a better knowledge of mankind's cultural heritage and also to the establishment of rational basis for its better conservation for the future generations. (Author)

  13. Evaluation of the radiology state at the CEA/Fontenay-aux-Roses and its environment; Point sur l'etat radiologique du CEA/Fontenay-aux-Roses et de son environnement

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-10-01

    Since 1946 the nuclear installations followed one other at the CEA of Fontenay-aux-Roses still their gradual stop the last ten years, except two installations INB34 and INB73, necessary for the wastes management. Today these installations form the subject of a drainage program. The public opinion is regularly informed on this program since 1999. This document presents the stock of the actions realized since this date: the track keeping of the sites activities impacts on the environment and the actions realized since 1999. (A.L.B.)

  14. RELIGION ET IMMIGRATION AUX ÉTATS-UNIS [Religion and immigration in the United States of America

    OpenAIRE

    Dumont, Gérard-François

    2012-01-01

    International audience In any country, the number of religions evolve according to the number of people who identify with the various religions and the number of people who deviate. In the United States, this type of evolution is particularly dependent on immigration resulting in significant changes in the religious distribution of the population. Aux États-Unis, l'évolution des effectifs des religions est tout particulièrement dépendant de l'immigration qui engendre des changements imp...

  15. Interactions entre les bacteries et les algues dans une culture continue de phytoplancton naturel soumise aux conditions exterieures

    OpenAIRE

    Gauthier, M; Martin, Y; Lelong, P; Breittmayer, V

    1984-01-01

    Au cours d'une expérience de culture continue de phytoplancton marin en grand volume soumise aux conditions extérieures, des tests microbiologiques et biochimiques ont été effectués pour mettre en évidence la production de substances antibactériennes et antialgales par les algues unicellulaires. De nombreux paramètres ont été mesurés pour caractériser la croissance de ces algues (qualitativement et quantitativement) et des bassin expérimental et dans la biomasse à différents stades de la cult...

  16. Mobilisations urbaines et espaces de résistance aux Jeux Olympiques de Londres et de Vancouver

    OpenAIRE

    Nativel, Corinne

    2012-01-01

    En juillet 2012, Londres accueillera les Jeux Olympiques et Paralympiques d’été. Partant du constat que l’organisation et la tenue de grands évènements sportifs suscitent d’importantes controverses et que les mouvements d’opposition aux JO restent encore méconnus, cet article propose d’identifier et d’analyser les mobilisations et espaces de résistance dans la capitale britannique. Il présente quelques éléments théoriques ainsi que la genèse et les principaux marqueurs contextuels des JO lond...

  17. Les références aux documents en ligne dans les textes scientifiques

    Directory of Open Access Journals (Sweden)

    Marc Couture

    2010-01-01

    Full Text Available [Français] Avec le développement de la diffusion en ligne de documents scientifiques, la primauté reconnue traditionnellement à l’imprimé devient de moins en moins pertinente ; les références à des ressources et documents en ligne forment ainsi une proportion significative des références dans certaines revues scientifiques, notamment celles qui, comme la RITPU, s’intéressent à l’information et à la communication. Dans cet article, on passe d’abord en revue les divers rôles des références répertoriés dans la littérature. On décrit ensuite les caractéristiques et les conditions permettant aux documents en ligne de jouer pleinement ces rôles. On montre enfin comment, dans l’adaptation française des normes de l’APA adoptée par la RITPU, certains choix touchant le format des notices des documents en ligne facilitent la tâche des évaluateurs et des lecteurs des articles. Par la même occasion, les auteurs y trouveront conseils et consignes visant à rendre plus pertinente et efficace cette dimension souvent négligée de la communication scientifique. [English] With the increase of online scientific publications, the traditional primacy of print documents has become less and less relevant. In some scientific journals, notably in the field of information technology and its applications (like IJTHE, a significant part of the citations now refer to online documents. This paper first reviews the various roles played by citations in scientific texts according to the literature. It then describes the characteristics and conditions which must be met if citations to online documents are to fully play these roles. Finally, it shows how, in the French-language adaptation of the APA reference formats which was adopted by IJTHE, a few choices have been made regarding online references in order to ease the task of both referees and readers. By the same token, authors will find guidelines and suggestions which should improve

  18. Limit to the measurement of feeble activities using ionization chambers; Limite des possibilites de mesure de faibles activites au moyen de chambres d'ionisation

    Energy Technology Data Exchange (ETDEWEB)

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

    1958-07-01

    The present account based on experience acquired in the Biology Service, in measuring feeble activities of tritium and carbon-14 has been prepared for the benefit hose who have to carry out measurements of feeble activities using ionization chambers. Precision are given on the behaviour and actual performance of vibrating condenser electrometers, based on approximately two years operating experience. It is shown that the possibilities of utilisation are not limited as is generally believed by insufficient sensitivity and stability of the electronic equipment, but by the existence of various parasitic phenomena coming from the ionization chamber itself, which make very difficult the measurement of ionization currents which are less than 10{sup -14} A. (author)Fren. [French] Le present compte rendu, base sur l'experience acquise au Service de Biologie dans la mesure de faibles activites de tritium et de carbone-14, est redige a l'intention des personnes ayant a effectuer des mesures de tres faibles activites au moyen de chambres d'ionisation. Il donne des precisions sur le comportement et les performances reelles des electrometres a condensateur vibrant, basees sur environ deux ans d'utilisation, et demontre que les possibilites de mesure ne sont pas limitees - comme on le croit generalement - par l'insuffisance de sensibilite et de stabilite de l'appareillage electronique, mais par l'existence de divers phenomenes parasites dont la chambre d'ionisation est le siege et qui rendent tres difficiles la mesure de courants d'ionisation inferieurs a 10{sup -14} A. (auteur)

  19. Fragmentation, auto-modification and post ionisation proton bound dimer ion formation: the differential mobility spectrometry of low molecular weight alcohols.

    Science.gov (United States)

    Ruszkiewicz, D M; Thomas, C L P; Eiceman, G A

    2016-08-01

    Differential mobility spectrometry (DMS) is currently being used for environmental monitoring of space craft atmospheres and has been proposed for the rapid assessment of patients at accident and emergency receptions. Three studies investigated hitherto undescribed complexity in the DMS spectra of methanol, ethanol, propan-1-ol and butan-1-ol product ions formed from a (63)Ni ionisation source. 54 000 DMS spectra obtained over a concentration range of 0.01 mg m(-3)(g) to 1.80 g m(-3)(g) revealed the phenomenon of auto-modification of the product ions. This occurred when the neutral vapour concentration exceeded the level required to induce a neutral-ion collision during the low field portion of the dispersion field waveform. Further, post-ionisation cluster-ion formation or protonated monomer/proton bound dimer inter-conversion within the ion-filter was indicated by apparent shifts in the values of the protonated monomer compensation field maximum; indicative of post-ionisation conversion of the protonated monomer to a proton-bound dimer. APCI-DMS-quadrupole mass spectrometry studies enabled the ion dissociation products from dispersion-field heating to be monitored and product ion fragmentation relationships to be proposed. Methanol was not observed to dissociate, while propan-1-ol and butan-1-ol underwent dissociation reactions consistent with dehydration processes that led ultimately to the generation of what is tentatively assigned as a cyclo-C3H3(+) ion (m/z 39) and hydrated protons. Studies of the interaction of ion filter temperature with dispersion-field heating of product ions isolated dissociation/fragmentation product ions that have not been previously described in DMS. The implications of these combined findings with regard to data sharing and data interpretation were highlighted. PMID:27227997

  20. Ionisation and dissociation of diarylmethyl chlorides in BCl/sub 3/CH/sub 2/Cl/sub 2/ solution: Spectroscopic evidence for carbenium ion pairs

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, R.; Mayr, H.; Plesch, P.H.

    1987-12-01

    The ionisation equilibria of diarylmethyl chlorides Ar/sub 2/CHCl (Ar = p-CH/sub 3/O-C/sub 6/H/sub 4/, p-PhO-C/sub 6/H/sub 4/, p-CH/sub 3/-C/sub 6/H/sub 4/) reacting with BCl/sub 3/ in CH/sub 2/Cl/sub 2/ to give ion-pairs Ar/sub 2/CH/sup +/BCl/sub 4//sup -/ (K/sub 1/), and the dissociation of these (K/sub D/) were studied by conductimetry and spectro-photometry. The molar conductivities are almost independent of the nature of the aryl group (approx. = 3.5.10/sup -3/ Sm/sup 2/mol at -70/sup 0/C). The ionisation constants K/sub I/ increase strongly with increasing electron releasing ability of the p-substituents. The standard ionisation enthalpies and entropies for (p-CH/sub 3/-C/sub 6/H/sub 4/)/sub 2/CHCl and (p-PhO-C/sub 6/H/sub 4/)(Ph)CHCl, calculated from the K/sub I/ at different temperatures are negative. The dissociation constants K/sub D/ ((1.9-2.9).10/sup -4/ molL at -70/sup 0/C) do not show a systematic dependence on the electron donating abilities of the substituents in the aryl groups. Small differences between the UV-vis absorption spectra of unpaired and paired ions were used to confirm the conductimetrically determined values of K/sub D/.

  1. ^Das^ Fulleren C 60 als molekulare Sonde für Untersuchungen zum Elektronentransfer beim massenspekrometrischen Verfahren der Desorption/Ionisation

    OpenAIRE

    Klemmt, Maren

    2004-01-01

    Das Ziel dieser Arbeit war, die chemisch-physikalischen bzw. optischen Eigenschaften des Fullerens C60 zu nutzen, um Aufklärung über die Rolle von Elektron- oder Energietransferprozessen bei der Anwendung der Desorption/Ionisation in der Massenspektrometrie von Biomolekülen zu erhalten. Dazu sind massenspektrometrische und optisch-spektroskopische Untersuchungen von Proben durchgeführt worden, denen vor allem beta-Carotin oder z.B. Chlorophyll-a im Sinne einer Matrix hinzugegeben wurden. Zur ...

  2. Identification of barley and rye varieties using matrix- assisted laser desorption/ionisation time-of-flight mass spectrometry with neural networks

    DEFF Research Database (Denmark)

    Bloch, H.A.; Petersen, Marianne Kjerstine; Sperotto, Maria Maddalena;

    2001-01-01

    Cereal varieties are normally identified using time-consuming methods such as visual examination of either the intact grain or one-dimensional electrophoretic patterns of the grain storage proteins. A fast method for identification of wheat (Triticum aestivum L.) varieties has previously been...... developed, which combines analysis of alcohol-soluble wheat proteins (gliadins) using matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry with neural networks. Here we have applied the same method for the identification of both barley (Hordeum vulgare L.) and rye (Secale cereale L...

  3. Thermally and optically stimulated luminescence of AlN-Y2O3 ceramics after ionising irradiation

    DEFF Research Database (Denmark)

    Trinkler, L.; Bos, A.J.J.; Winkelman, A.J.M.;

    1999-01-01

    Thermally (TL) and optically stimulated luminescence (OSL) were studied in AlN-Y2O3 ceramics after irradiation with ionising radiation. The extremely high TL sensitivity (approximately 60 times the sensitivity of LiF:Mg,Tl (TLD-100)) makes AlN-Y2O3 ceramics attractive as a TLD material. However, an...... spectral properties and thermal evolution of OSL are also presented. The stimulation spectrum covers the spectral range from green to infrared light. A combination of thermal and optical stimulation allowed a correlation to be found between parameters of OSL and TL after the same irradiation dose. It is...

  4. Identification of wheat varieties using matrix-assisted laserdesorption/ionisation time-of-flight mass spectrometry and anartificial neural network

    DEFF Research Database (Denmark)

    Bloch, Helle Aagaard; Kesmir, Can; Petersen, Marianne Kjerstine;

    1999-01-01

    A novel tool for variety identification of wheat (Triticum aestivum L.) has been developed: an artificialneural network (ANN) is used to classify the gliadin fraction analysed by matrix-assisted laserdesorption/ionisation time-of-flight mass spectrometry (MALDI-TOFMS). The robustness of this...... novelmethod with respect to various experimental parameters has been tested. The results can be summarised: (i)With this approach 97% of the wheat varieties can be classified correctly with a corresponding correlationcoefficient of 1.0, (ii) The method is fast since the time of extracting gliadins from flour...

  5. $\\beta$-decay study of neutron-rich Tl, Pb, and Bi by means of the pulsed-release technique and resonant laser ionisation

    CERN Multimedia

    Lettry, J

    2002-01-01

    It is proposed to study new neutron-rich nuclei around the Z = 82 magic shell closure, with major relevance for understanding the evolution of nuclear structure at extreme isospin values. Following the IS354 experiment, $\\beta$-decay studies of neutron-rich thallium, lead and bismuth isotopes will be performed for 215 $\\leqslant$ A $\\leqslant$ 219. To this purpose the pulsed-release technique, which was pioneered at ISOLDE, will be optimised. It will be complemented with the higher element selectivity that can be obtained by the unique features of resonant laser ionisation, available at ISOLDE from the RILIS source.

  6. Automatic device for measuring {beta}-emitting sources: P.A.P.A. {beta}-meters; Dispositif automatique pour la mesure de sources emettrices de rayonnement {beta}: P.A.P.A. {beta} metres

    Energy Technology Data Exchange (ETDEWEB)

    Colomer, J.; Valentin, M. [Commissariat a l' Energie Atomique, Bruyeres-le-Chatel (France). Centre d' Etudes

    1969-07-01

    The apparatus described is designed for measuring {beta}-emitting elements by the absorption method; it is suitable for carrying out a large number of routine analyses. A mechanical device pushes an aluminium absorption set automatically between the source and the detector; the movement is programmed for cutting on and off by a transistorized electronic unit, with printing out and punching of the results on tape; then this can be mathematically processed by a computer (tracing of absorption spectra, extrapolation and calculation of the activity). The detector is either a {beta}-probe or a proportional counter with a specially designed loop. For routine measurements, the accuracy obtained, with all corrections made, is from 5 to 8 per cent; the reproducibility is about 2 per cent. (authors) [French] L'appareillage decrit est destine aux mesures des elements emetteurs {beta} par la methode d'absorption et il permet d'effectuer, en routine, un nombre important de mesures. Un ensemble mecanique effectue le passage automatique, sous vide primaire, d'un jeu d'absorption en aluminium entre la source et le detecteur, ce passage est programme en pre-temps ou pre-coup par un ensemble electronique a transistors, avec impression et perforation sur bandes des resultats des mesures pour traitement mathematique par un ordinateur (trace du spectre d'absorption, extrapolation et calcul d'activite). Le detecteur est soit une sonde {beta}, soit un compteur proportionnel a boucle specialement realise. Sur des mesures de routine, la precision obtenue, toutes corrections effectuees, est de 5 a 8 pour cent et la reproductibilite de l'ordre de 2 pour cent. (auteur)

  7. Apoptosis is signalled early by low doses of ionising radiation in a radiation-induced bystander effect

    Energy Technology Data Exchange (ETDEWEB)

    Furlong, Hayley, E-mail: hayley.furlong@dit.ie [DIT Centre for Radiation and Environmental Science, Focas Research Institute, Dublin Institute of Technology, Kevin St, Dublin 8 (Ireland); School of Biological Sciences, College of Sciences and Health, Dublin Institute of Technology, Kevin St, Dublin 8 (Ireland); Mothersill, Carmel [Medical Physics and Applied Radiation Sciences, Nuclear Research Building, 1280 Hamilton, Ontario L8S 4K1 (Canada); Lyng, Fiona M. [DIT Centre for Radiation and Environmental Science, Focas Research Institute, Dublin Institute of Technology, Kevin St, Dublin 8 (Ireland); Howe, Orla [DIT Centre for Radiation and Environmental Science, Focas Research Institute, Dublin Institute of Technology, Kevin St, Dublin 8 (Ireland); School of Biological Sciences, College of Sciences and Health, Dublin Institute of Technology, Kevin St, Dublin 8 (Ireland)

    2013-01-15

    Highlights: ► Molecular mechanisms involved in the production of a radiation induced bystander effect are not well known. ► We investigate gene expression changes in apoptotic genes in both direct and bystander responses. ► We demonstrate initiation of the apoptotic cascade in a bystander response. ► Lower doses reveal a specific but differential response related to apoptosis compared to higher doses. - Abstract: It is known that ionising radiation (IR) induces a complex signalling apoptotic cascade post-exposure to low doses ultimately to remove damaged cells from a population, specifically via the intrinsic pathway. Therefore, it was hypothesised that bystander reporter cells may initiate a similar apoptotic response if exposed to low doses of IR (0.05 Gy and 0.5 Gy) and compared to directly irradiated cells. Key apoptotic genes were selected according to their role in the apoptotic cascade; tumour suppressor gene TP53, pro-apoptotic Bax and anti-apoptotic Bcl2, pro-apoptotic JNK and anti-apoptotic ERK, initiator caspase 2 and 9 and effector caspase 3, 6 and 7. The data generated consolidated the role of apoptosis following direct IR exposure for all doses and time points as pro-apoptotic genes such as Bax and JNK as well as initiator caspase 7 and effector caspase 3 and 9 were up-regulated. However, the gene expression profile for the bystander response was quite different and more complex in comparison to the direct response. The 0.05 Gy dose point had a more significant apoptosis gene expression profile compared to the 0.5 Gy dose point and genes were not always expressed within 1 h but were sometimes expressed 24 h later. The bystander data clearly demonstrates initiation of the apoptotic cascade by the up-regulation of TP53, Bax, Bcl-2, initiator caspase 2 and effector caspase 6. The effector caspases 3 and 7 of the bystander samples demonstrated down-regulation in their gene expression levels at 0.05 Gy and 0.5 Gy at both time points therefore not

  8. [Low dose ionising radiation and cancer: findings and methods. Report of a meeting and consequences for Switzerland].

    Science.gov (United States)

    Schüler, G; Gutzwiller, F

    1991-01-01

    Today's society is concerned about the dangers of ionising radiation, especially in the aftermath of Chernobyl. On the other hand, there exists a widespread lack of understanding radiation biology and radioepidemiology--the very sciences which provide the data from which today's risk estimates have been derived. The papers in this issue of the Journal were presented at a workshop on "Low level radiation and cancer: data and methods" held on 10th-11th December in Feuisberg, near Zurich. The meeting was organised by the Institute of Social and Preventive Medicine of the University of Zurich under the auspices of the Swiss Federal Office of Public Health. Its aims were threefold. First, to give an introduction to some basic facts and methodological issues in radiation physics, biology and epidemiology. Secondly, to give an overview of the availability of data for radioepidemiological research in Switzerland and, thirdly, to evaluate possible research strategies in this country. A list of some notions and units commonly used in the radiation sciences serves an an introduction to the field (G. Schüler et al.). In using units and notions it is important to distinguish the description of biological experiments and epidemiological observations from definitions and risk projections proposed by international reports and consensus bodies for radioprotection purposes. The next papers deal more specifically with selected aspects of the basic sciences. Dosimetry means quantifying the physical effects of ionizing radiation in human tissue; this is not a straight-forward procedure (I. Cordt). The foundations of general radiation biology are succinctly summarised by C. Michel. An account of our present knowledge and theories of radiation carcinogenesis is provided by W. Burkart. W Lutz compares dose-response models of chemical carcinogenesis with those used in radiation carcinogenesis. During the last decade the epidemiological foundations of radioprotection have changed

  9. Les ecarts de financement en matiere d'adaptation aux changements climatiques - avec la perspective des CPDN

    DEFF Research Database (Denmark)

    Olhoff, Anne; Bee, Skylar; Puig, Daniel

    rapport sur les écarts financiers et les options permettant de les combler. Le rapport sera publié au printemps 2016. Cette mise à jour doit contribuer aux débats lors de la 21ème session de la Conférence des Parties (COP 21) à la Convention-Cadre des Nations Unies sur les Changements Climatiques (CCNUCC......). Elle comprend les principales conclusions concernant les coûts et les financements de l’adaptation aux changements climatiques du rapport AGR 2014 du PNUE ainsi que les conclusions préliminaires de l’évaluation de 2016. De plus, elle s’appuie sur les réflexions concernant les coûts de l’adaptation et...... les besoins de financement présentes dans les composantes adaptation des Contributions Prévues Déterminées au niveau National (CPDN) (INDC) – soit les engagements post 2020 que les pays se proposent mettre en oeuvre dans le cadre d’un nouvel accord mondial sur les changements climatiques....

  10. INFLUENCE DE LA STRUCTURE ET DE LA SEGREGATION AUX JOINTS DE GRAINS SUR LES PROPRIETES ELECTRIQUES ET LE RENDEMENT PHOTOVOLTAIQUE DU SILICIUM POLYCRISTALLIN

    OpenAIRE

    Maurice, J.; Laval, J

    1982-01-01

    On relie les propriétés électriques et structurales des joints de grains dans le cas du silicium polycristallin produit par la méthode Bridgman (C.G.E.), en comparant les mesures macroscopiques de réponse photovoltaïque (LBIC) et de chute de potentiel aux joints, aux analyses cristallographiques et chimiques effectuées en microscopie électronique (STEM, EDS, EELS). On peut distinguer trois types de joints : 1) les joints plans -cohérents- qui n'influent pas sur le photocourant, à moins d'être...

  11. Homosexualité/hétérosexualité : les enquêtes sur les comportements sexuels en France et aux USA

    OpenAIRE

    Lhomond, Brigitte; Michaels, Stuart

    2009-01-01

    Cet article propose une analyse des résultats concernant l’attirance et les pratiques homosexuelles dans les deux enquêtes nationales récentes sur les comportements sexuels en France et aux USA. On observe des attitudes sociales différentes vis‑à‑vis de l’homosexualité dans les deux pays avec une beaucoup plus grande acceptation en France, une affirmation plus nette de l’attirance homosexuelle aux Etats‑Unis, surtout chez les hommes et une structuration socio-démographique assez similaire des...

  12. Le secteur bovin (viande et lait): quel avenir face aux évolutions des marchés et de la PAC ?

    OpenAIRE

    Chatellier, Vincent

    2010-01-01

    Cette communication propose une synthèse des principales évolutions économiques de la filière bovine. Elle présente, dans un premier temps, l’évolution de la production, de la consommation et des échanges de viande bovine aux échelles internationales, communautaires et françaises. Dans une même logique, elle s’intéresse ensuite au secteur laitier. Dans une dernière partie, une réflexion est proposée quant aux évolutions pressenties de la PAC pour ces deux productions agricoles....

  13. Tolérance aux fautes dans les applications J2EE: Une solution scalable et générique

    OpenAIRE

    Bouchenak, Sara; Krakowiak, Sacha; De Plama, Noël

    2005-01-01

    La plate-forme J2EE définit un modèle pour développer des applications réparties dans une architecture multi-tiers, telles que les applications Web de commerce électronique. Avec la multiplication des couches logicielles et intergicielles, les applications Internet sont encore plus sujettes aux défaillances ; ces défaillances étant, pour la majorité, causées par des fautes logicielles ou des fautes de l'opérateur. Dans cet article, nous proposons un système de tolérance aux fautes qui traite ...

  14. Resonance ionisation mass spectrometry

    International Nuclear Information System (INIS)

    This report presents the results of an investigation of the technique resonance ionization mass spectroscopy. It offers the possibility of quick, accurate and highly sensitive analysis of samples which have undergone a minimum of chemical pretreatment. The technique can be applied to the detection of elements in trace amounts and for the detection of isotopes. Sample preparation, low-level counting and instrumentation are discussed. The proven capabilities and limitations of the technique and its commercial application and potential are presented. (U.K.)

  15. Acid-yield measurements of the gas-phase ozonolysis of ethene as a function of humidity using Chemical Ionisation Mass Spectrometry (CIMS

    Directory of Open Access Journals (Sweden)

    K. E. Leather

    2012-01-01

    Full Text Available Gas-phase ethene ozonolysis experiments were conducted at room temperature to determine formic acid yields as a function of relative humidity (RH using the integrated EXTreme RAnge chamber-Chemical Ionisation Mass Spectrometry technique, employing a CH3I ionisation scheme. RHs studied were <1, 11, 21, 27, 30 % and formic acid yields of (0.07±0.01 and (0.41±0.07 were determined at <1 % RH and 30 % RH respectively, showing a strong water dependence. It has been possible to estimate the ratio of the rate coefficient for the reaction of the Criegee biradical, CH2OO with water compared with decomposition. This analysis suggests that the rate of reaction with water ranges between 1×10−12–1×10−15 cm3 molecule−1 s−1 and will therefore dominate its loss with respect to bimolecular processes in the atmosphere. Global model integrations suggest that this reaction between CH2OO and water may dominate the production of HC(OOH in the atmosphere.

  16. DNA double-strand breaks as potential indicators for the biological effects of ionising radiation exposure from cardiac CT and conventional coronary angiography: a randomised, controlled study

    Energy Technology Data Exchange (ETDEWEB)

    Geisel, Dominik; Zimmermann, Elke; Rief, Matthias; Greupner, Johannes; Hamm, Bernd [Charite Medical School, Department of Radiology, Berlin (Germany); Laule, Michael; Knebel, Fabian [Charite Medical School, Department of Cardiology, Berlin (Germany); Dewey, Marc [Charite Medical School, Department of Radiology, Berlin (Germany); Charite, Institut fuer Radiologie, Berlin (Germany)

    2012-08-15

    To prospectively compare induced DNA double-strand breaks by cardiac computed tomography (CT) and conventional coronary angiography (CCA). 56 patients with suspected coronary artery disease were randomised to undergo either CCA or cardiac CT. DNA double-strand breaks were assessed in fluorescence microscopy of blood lymphocytes as indicators of the biological effects of radiation exposure. Radiation doses were estimated using dose-length product (DLP) and dose-area product (DAP) with conversion factors for CT and CCA, respectively. On average there were 0.12 {+-} 0.06 induced double-strand breaks per lymphocyte for CT and 0.29 {+-} 0.18 for diagnostic CCA (P < 0.001). This relative biological effect of ionising radiation from CCA was 1.9 times higher (P < 0.001) than the effective dose estimated by conversion factors would have suggested. The correlation between the biological effects and the estimated radiation doses was excellent for CT (r = 0.951, P < 0.001) and moderate to good for CCA (r = 0.862, P < 0.001). One day after radiation, a complete repair of double-strand breaks to background levels was found in both groups. Conversion factors may underestimate the relative biological effects of ionising radiation from CCA. DNA double-strand break assessment may provide a strategy for individualised assessments of radiation. (orig.)

  17. Cyclic nucleotide Response Element Binding protein (CREB) activation promotes survival signal in human K562 erythroleukemia cells exposed to ionising radiation/etoposide combined treatment

    International Nuclear Information System (INIS)

    Anticancer therapy addresses the destruction of tumour cells which try to counteract the effect of drugs and/or ionising radiation. Thus the knowledge of the threshold over which the cells do not resist such agents could help in the setting up of therapy protocols. Since a key role was assigned to Cyclic nucleotide Response Element Binding protein (CREB) multigenic family (which is composed of several nuclear transcription factors involved in c-AMP signalling in cell differentiation, proliferation, apoptosis, survival and adaptive response and in hematopoiesis and acute leukemias), attention was paid to the activation of Erk cascade and of the downstream kinases and transcription factors such as p90 RSK and CREB. K562 erythroleukemia cell survival to 1.5 Gy ionising radiation with or without etoposide treatment seemed to involve Erk phosphorylation which, regulating p90 RSK, should activate CREB. In parallel, p38 MAP kinase activity down-modulation, along with low caspase-3 activity, and no modification of Bax and Bcl2 levels, supported such evidence. Thus, endogenous CREB activation, triggering a potent survival signal in K562 cells exposed to 1.5 Gy with or without etoposide, led us to suggest that using specific inhibitors against CREB, such as modified phosphorothionate oligodeoxynucleotides (ODN) corresponding to CREB-1 sequence, anticancer therapy efficacy could be improved. (author)

  18. DNA double-strand breaks as potential indicators for the biological effects of ionising radiation exposure from cardiac CT and conventional coronary angiography: a randomised, controlled study

    International Nuclear Information System (INIS)

    To prospectively compare induced DNA double-strand breaks by cardiac computed tomography (CT) and conventional coronary angiography (CCA). 56 patients with suspected coronary artery disease were randomised to undergo either CCA or cardiac CT. DNA double-strand breaks were assessed in fluorescence microscopy of blood lymphocytes as indicators of the biological effects of radiation exposure. Radiation doses were estimated using dose-length product (DLP) and dose-area product (DAP) with conversion factors for CT and CCA, respectively. On average there were 0.12 ± 0.06 induced double-strand breaks per lymphocyte for CT and 0.29 ± 0.18 for diagnostic CCA (P < 0.001). This relative biological effect of ionising radiation from CCA was 1.9 times higher (P < 0.001) than the effective dose estimated by conversion factors would have suggested. The correlation between the biological effects and the estimated radiation doses was excellent for CT (r = 0.951, P < 0.001) and moderate to good for CCA (r = 0.862, P < 0.001). One day after radiation, a complete repair of double-strand breaks to background levels was found in both groups. Conversion factors may underestimate the relative biological effects of ionising radiation from CCA. DNA double-strand break assessment may provide a strategy for individualised assessments of radiation. (orig.)

  19. Probing X-ray photoevaporative winds through their interaction with ionising radiation in cluster environments: the case for X-ray proplyds

    CERN Document Server

    Clarke, C J

    2014-01-01

    We show that if young low mass stars undergo vigorous X-ray driven disc winds, these may be detected in clusters through their interaction with ionising radiation from massive stars. We argue that in the ONC (Orion Nebula Cluster) one should see $\\sim$ 10s of `X-ray proplyds' ( objects with optically imaged offset ionisation fronts) in the range $0.3-0.6$pc from $\\theta_1$C Ori (the dominant O star in the ONC). Such objects lie outside the central `FUV zone' in the ONC where proplyds are instead well explained by neutral winds driven by external Far Ultraviolet (FUV) emission from $\\theta_1$C. We show that the predicted numbers and sizes of X-ray proplyds are compatible with those observed and that this may also explain at least some of the far flung proplyds seen in the Carina nebula. We compare the sizes of observed proplyds outside the FUV region of the ONC with model predictions based on the current observed X-ray luminosities of these sources ( bearing in mind that the current size is actually set by the...

  20. The use of ionising radiation from 60CO gamma source in controlling mouldiness in dried cocoa beans

    International Nuclear Information System (INIS)

    Mouldiness in stored cocoa beans in Ghana and the production of aflatoxin have been studied. Based on actual weight of discarded beans, mouldy beans have been estimated to constitute 0.13 % and 0.00002 % of marketable beans at the farmers' level and the buying agents' depots respectively in the Tafo District. This is contrasted with an estimated value of 0.16 % obtained in a questionnaire type study involving farmers. Estimated mouldy beans at the Tema port was 0.69 % per year (based on the cut test) representing a financial loss of $1,688,637.19 per year at $989/T should the mouldy beans be discarded. Fifty-eight (58) internally- and externally- borne fungal species were isolated from dried cocoa beans. Of these, forty-eight (48) were internally- borne and ten (10) were superficial. Twenty-nine (29) of the internally occurring fungi have been recorded for the first time on cocoa beans in Ghana. Twenty-six (26) of the fungi isolated belong to Aspergillus group. They included A. parasiticus and A. flavus, which can produce aflatoxins. Five (5) belong to Penicillium, eight (8) to Fusarium and nineteen (19) to other species. Ionising radiation effectively controlled fungi associated with mouldiness in cocoa beans in a dose - dependent manner. A radiation dose of 6 kGy completely inactivated the moulds. A. flavus and A. tamarii were the most radiation - resistant moulds encountered. The moisture content of the beans before, during and after irradiation influenced the effect of radiation. The relative humidity during storage and the type of packaging also influenced the radiation effect. Conidia of A. flavus subjected to moist heat at temperatures 20 0C to 60 0C for 2.5, 5 and 10 min respectively were not significantly affected by heating up to 50 0C. Heating an aqueous conidial suspension at 60 0C for at least 2.5 min reduced the number of fungal colonies by at least 5 log cycles when the suspension was assayed on agar plate media. Heating at 59 0C for 10 min

  1. Une méthode de production de truites fario destinées aux repeuplements de restauration

    Directory of Open Access Journals (Sweden)

    MAISSE G.

    1981-01-01

    Full Text Available Une méthode de production de populations de truites fario présentant une forte variabilité génétique est proposée pour les repeuplements de restauration. Du sperme de géniteurs sauvage est conservé à des températures voisines de 0° C et à l'obscurité, pendant la durée du transport entre le cours d'eau d'origine et la pisciculture, où l'on procède à l'insémination d'ovules de truites fario d'élevage en utilisant le dilueur de sperme 532. La descendance est destinée de préférence aux déversements au stade oeuf dans le milieu préalablement restauré.

  2. Environnements stellaire : des étoiles lambda Boötis aux disques protoplanétaires

    OpenAIRE

    Gonzalez, Jean-François

    2005-01-01

    J'ai effectué une étude des éléments C, N, et O dans les atmosphères d'étoiles chimiquement particulières de la séquence principale, où ils sont sous-abondants et répartis de manière inhomogène. J'ai recensé les processus physiques qu'il faut inclure dans les calculs d'accélération radiative et montré leur importance relative. Des améliorations majeures par rapport aux approximations usuelles ont été obtenues grâce à l'utilisation systématique des données atomiques du projet OPACITY. Elles pe...

  3. Les images de l’Arabie Saoudite aux États-Unis - De 1973 au 11 septembre 2001

    OpenAIRE

    Raymond Vidén, Anna

    2011-01-01

    Cette étude avance l’idée que la relation américano-saoudienne « spéciale » fait partie intégrante d’un récit sur la relation entre les États-Unis et l’Arabie Saoudite, créé par la compagnie pétrolière ARAMCO et entretenu par Washington au travers de déclarations, doctrines politiques et voyages officiels en Arabie Saoudite. L’Arabie Saoudite elle-même entretient ce récit avec sa diplomatie publique et l’influence exercée par le « lobby saoudien » aux États-Unis. Ce récit souligne l’importanc...

  4. The Politics of Religion in the United States Manifestations politiques de la religion aux États-Unis

    Directory of Open Access Journals (Sweden)

    Josef Braml

    2011-04-01

    Full Text Available Aux États-Unis, les attitudes religieuses ont plus d’influence sur les choix politiques que dans n’importe quelle autre démocratie occidentale. L’engagement religieux/moral de la droite chrétienne polarise les États-Unis, ce qui a des conséquences sur le plan électoral mais aussi sur les choix politiques réels. L’importance de la droite chrétienne dans la coalition électorale du Parti républicain oblige celui-ci à mettre l’accent sur les questions liées à la sécurité nationale, en particulier la lutte anti-terroriste, afin de mieux souder une coalition électorale hétérogène.

  5. ALDUY Cécile, WAHNICH Stéphane, 2015, Marine Le Pen prise aux mots

    OpenAIRE

    Née, Émilie

    2016-01-01

    Alors que le discours politique est l’objet privilégié, l’objet « noble », presque naturel de l’analyse de discours française (du côté de la lexicologie comme de la rhétorique), peu de chercheurs se sont penchés sur les discours des dirigeants du Front national. Et pourtant, comme l’indique Cécile Alduy en ouverture de Marine Le Pen prise aux mots, l’histoire du Front national « c’est aussi, fondamentalement, une histoire de mots » (p. 14). Ce paradoxe s’explique si l’on considère le discours...

  6. Le registre aux notices de Dinant : le nombre d'affaires d'avortement transmises à la justice

    OpenAIRE

    Villers, Stéphanie

    2013-01-01

    L’analyse des articles du Code pénal sanctionnant l’avortement a prouvé combien il était malaisé de rassembler et de démontrer les quatre éléments constitutifs de l’avortement. Dans l’impasse face à cette infraction d’un autre genre, la justice n’a souvent d’autre choix que d’abandonner les poursuites. L’orientation dominante des affaires d’avortement est donc le sans suite ou le non-lieu. Comment les connaître et les quantifier ? À cet égard, le registre aux notices, témoin de l’activité du ...

  7. Dépouillement de l'essai aux barres de Hopkinson par une technique de calcul inverse

    OpenAIRE

    Gary, G.; Zhao, H

    1994-01-01

    Le dépouillement classique des essais aux barres d'Hopkinson ne permet pas la mesure directe d'une relation précise "contrainte-déformation" à vitesse de déformation constante en raison du non équilibre des forces et de la variation importante de vitesse de déformation au cours de l'essai, en particulier dans la zone des faibles déformations. Nous proposons ici une méthode de dépouillement basée sur une technique du calcul inverse permettant de passer outre ces limitations, et d'améliorer ain...

  8. Le "non-recours" aux soins des populations précaires. Constructions et réceptions des normes.

    OpenAIRE

    Rode, Antoine

    2010-01-01

    Les populations précaires sont celles pour qui persistent les difficultés dans l'accès et l'utilisation des soins, alors que leur état de santé est plus dégradé que pour le reste de la population. Ces constats communs à plusieurs études viennent pleinement réinterroger l'effectivité des dispositifs – protection et services de soins – mis en place en France depuis les années 1990 pour favoriser l'accès aux soins de tous. Dans ce contexte, la question du « non-recours » dans le domaine des soin...

  9. Marketers as Innovators: how ethnic marketing revisits ethnicity Marketing ethnique et innovation aux États-Unis

    Directory of Open Access Journals (Sweden)

    Marie-Christine Pauwels

    2009-10-01

    Full Text Available L’innovation aux États-Unis est ici vue sous un angle social et culturel. Il ne s’agit plus d’étudier l’innovation technologique, mais l’innovation en matière de produit. L’article aborde la création de valeur à travers la variable ethnique dans le domaine de la vente, du marketing et de la publicité. Les nouvelles tendances en matière d’ethno-marketing sont analysées, en particulier la manière dont les professionnels utilisent la notion d’ethnicité pour vendre des produits de consommation courante à un marché de consommateurs de plus en plus exigeants, soit en ayant recours à une segmentation de ces consommateurs en micro-marchés toujours plus étroits, soit en privilégiant un marketing multi- ou trans-culturel.

  10. Décentraliser la gestion de réseaux grâce aux agents mobiles

    OpenAIRE

    Galtier, Virginie

    1998-01-01

    Stage de DEA. Rapport de stage.; Dans un contexte où les réseaux informatiques et de télécommunications prennent une importance toujours plus critique, la gestion de réseaux devient une activité cruciale. Mais les systèmes inspirés du modèle centralisé de l'OSI et largement utilisés s'adaptent mal aux nouvelles caractéristiques des réseaux actuels (de plus en plus évolutifs). Utiliser les agents mobiles pour décentraliser cette gestion permettrait de gagner en efficacité en distribuant la tâc...

  11. L’institutionnalisme de John Commons et les origines de l’État providence aux États-Unis

    Directory of Open Access Journals (Sweden)

    Isabel da Costa

    2010-12-01

    Full Text Available La politique officielle des États-Unis, soutenue par la pensée économique et juridique, était à l’origine le « laissez-faire » sur le marché et dans les relations de travail. Cet article analyse la construction d’un rôle légitime pour l’État dans la régulation sociale du marché du travail à travers l’ébauche de réglementations du travail et l’émergence de dispositifs de protection sociale aux États-Unis. Nous analyserons tout d’abord comment le mouvement progressiste a impulsé certaines réformes sociales établissant les prémisses d’une législation sociale ; nous nous attacherons ensuite à démontrer la contribution majeure de l’institutionnalisme de John Commons et de ses disciples de l’université du Wisconsin à la conception et au développement de l’État providence aux États-Unis.The official policy of the United States, backed by economic and legal thought, was originally “laissez-faire” on the market and in labor relations. This article analyzes the development of a legitimate role for the state in the social regulation of the labor market through the emergence of the early labor regulations and social protection schemes in the United States. We first analyze how the progressive movement brought about certain social reforms establishing the beginnings of social legislation; we will then focus on the major contribution of the institutionalism of John Commons and his followers from the University of Wisconsin to the design and the development of the welfare state in the United States.

  12. Diversification and expression of the PIN, AUX/LAX and ABCB families of putative auxin transporters in Populus

    Directory of Open Access Journals (Sweden)

    Nicola eCarraro

    2012-02-01

    Full Text Available Intercellular transport of the plant hormone auxin is mediated by three families of membrane-bound protein carriers, with the PIN and ABCB families coding primarily for efflux proteins and the AUX/LAX family coding for influx proteins. In the last decade our understanding of gene and protein function for these transporters in Arabidopsis has expanded rapidly but very little is known about their role in woody plant development. Here we present a comprehensive account of all three families in the model woody species Populus, including chromosome distribution, protein structure, quantitative gene expression, and evolutionary relationships. The PIN and AUX/LAX gene families in Populus comprise 16 and 8 members respectively, and show evidence for the retention of paralogs following a relatively recent whole genome duplication. There is also evidence for differential expression across tissues within many gene pairs. The ABCB family is previously undescribed in Populus and includes 20 members, showing a much deeper evolutionary history including both tandem and whole genome duplication as well as probable loss. A striking number of these transporters are expressed in developing Populus stems and we suggest that evolutionary and structural relationships with known auxin transporters in Arabidopsis can point toward candidate genes for further study in Populus. This is especially important for the ABCBs, which is a large family and includes members in Arabidopsis that are able to transport other substrates in addition to auxin. Protein modeling, sequence alignment and expression data all point to ABCB1.1 as a likely auxin transport protein in Populus. Given that basipetal auxin flow through the cambial zone shapes the development of woody stems, it is important that we identify the full complement of proteins involved in this process. This work should lay the foundation for studies targeting specific proteins for functional characterization and in situ

  13. The auxin transporter, OsAUX1, is involved in primary root and root hair elongation and in Cd stress responses in rice (Oryza sativa L.).

    Science.gov (United States)

    Yu, ChenLiang; Sun, ChenDong; Shen, Chenjia; Wang, Suikang; Liu, Fang; Liu, Yan; Chen, YunLong; Li, Chuanyou; Qian, Qian; Aryal, Bibek; Geisler, Markus; Jiang, De An; Qi, YanHua

    2015-09-01

    Auxin and cadmium (Cd) stress play critical roles during root development. There are only a few reports on the mechanisms by which Cd stress influences auxin homeostasis and affects primary root (PR) and lateral root (LR) development, and almost nothing is known about how auxin and Cd interfere with root hair (RH) development. Here, we characterize rice osaux1 mutants that have a longer PR and shorter RHs in hydroponic culture, and that are more sensitive to Cd stress compared to wild-type (Dongjin). OsAUX1 expression in root hair cells is different from that of its paralogous gene, AtAUX1, which is expressed in non-hair cells. However, OsAUX1, like AtAUX1, localizes at the plasma membrane and appears to function as an auxin tranporter. Decreased auxin distribution and contents in the osaux1 mutant result in reduction of OsCyCB1;1 expression and shortened PRs, LRs and RHs under Cd stress, but may be rescued by treatment with the membrane-permeable auxin 1-naphthalene acetic acid. Treatment with the auxin transport inhibitors 1-naphthoxyacetic acid and N-1-naphthylphthalamic acid increased the Cd sensitivity of WT rice. Cd contents in the osaux1 mutant were not altered, but reactive oxygen species-mediated damage was enhanced, further increasing the sensitivity of the osaux1 mutant to Cd stress. Taken together, our results indicate that OsAUX1 plays an important role in root development and in responses to Cd stress.

  14. Risk of cancer from occupational exposure to ionising radiation: retrospective cohort study of workers in France, the United Kingdom, and the United States (INWORKS)

    Science.gov (United States)

    Cardis, Elisabeth; Daniels, Robert D; Gillies, Michael; O’Hagan, Jacqueline A; Hamra, Ghassan B; Haylock, Richard; Laurier, Dominique; Leuraud, Klervi; Moissonnier, Monika; Schubauer-Berigan, Mary K; Thierry-Chef, Isabelle; Kesminiene, Ausrele

    2015-01-01

    Study question Is protracted exposure to low doses of ionising radiation associated with an increased risk of solid cancer? Methods In this cohort study, 308 297 workers in the nuclear industry from France, the United Kingdom, and the United States with detailed monitoring data for external exposure to ionising radiation were linked to death registries. Excess relative rate per Gy of radiation dose for mortality from cancer was estimated. Follow-up encompassed 8.2 million person years. Of 66 632 known deaths by the end of follow-up, 17 957 were due to solid cancers. Study answer and limitations Results suggest a linear increase in the rate of cancer with increasing radiation exposure. The average cumulative colon dose estimated among exposed workers was 20.9 mGy (median 4.1 mGy). The estimated rate of mortality from all cancers excluding leukaemia increased with cumulative dose by 48% per Gy (90% confidence interval 20% to 79%), lagged by 10 years. Similar associations were seen for mortality from all solid cancers (47% (18% to 79%)), and within each country. The estimated association over the dose range of 0-100 mGy was similar in magnitude to that obtained over the entire dose range but less precise. Smoking and occupational asbestos exposure are potential confounders; however, exclusion of deaths from lung cancer and pleural cancer did not affect the estimated association. Despite substantial efforts to characterise the performance of the radiation dosimeters used, the possibility of measurement error remains. What this study adds The study provides a direct estimate of the association between protracted low dose exposure to ionising radiation and solid cancer mortality. Although high dose rate exposures are thought to be more dangerous than low dose rate exposures, the risk per unit of radiation dose for cancer among radiation workers was similar to estimates derived from studies of Japanese atomic bomb survivors. Quantifying the cancer risks associated

  15. Radiation induced sterility to control tsetse flies. The effect of ionising radiation and hybridisation on tsetse biology and the use of the sterile insect technique in integrated tsetse control.

    NARCIS (Netherlands)

    Vreysen, M.J.B.

    1995-01-01

    The induction of dominant lethal mutations by exposing tsetse flies as pupae or adult insects to ionising radiation and the use of hybrid sterility resulting from crosses of closely related tsetse species or subspecies, are potential methods of genetic control of tsetse flies. In this thesis the eff

  16. Politiques et idéaux éducatifs de l'Ecole québécoise et française (1963-2004). Évolutions et enjeux des discours relatifs aux valeurs et aux finalités de l'éducation scolaire du rapport Parent au rapport Thélot.

    OpenAIRE

    GIOL, Franck

    2013-01-01

    Les mutations qui affectent l’éducation scolaire des sociétés occidentales de l’après Deuxième Guerre mondiale peuvent être lues comme la marque d’une décomposition de la modernité, décomposition considérée par certains auteurs comme l’un des traits les plus saillants de la postmodernité. A ce titre, elles ne peuvent manquer d’affecter les idéaux éducatifs, et plus particulièrement les valeurs et les finalités dont l’Ecole contemporaine se trouve investie.La fin du récit de l’émancipation par...

  17. Secondary ionisations in a wall-less ion-counting nanodosimeter: quantitative analysis and the effect on the comparison of measured and simulated track structure parameters in nanometric volumes

    Science.gov (United States)

    Hilgers, Gerhard; Bug, Marion U.; Gargioni, Elisabetta; Rabus, Hans

    2015-10-01

    The object of investigation in nanodosimetry is the physical characteristics of the microscopic structure of ionising particle tracks, i.e. the sequence of the interaction types and interaction sites of a primary particle and all its secondaries, which reflects the stochastic nature of the radiation interaction. In view of the upcoming radiation therapy with protons and carbon ions, the ionisation structure of the ion track is of particular interest. Owing to limitations in current detector technology, the only way to determine the ionisation cluster size distribution in a DNA segment is to simulate the particle track structure in condensed matter. This is done using dedicated computer programs based on Monte Carlo procedures simulating the interaction of the primary ions with the target. Hence, there is a need to benchmark these computer codes using suitable experimental data. Ionisation cluster size distributions produced in the nanodosimeter's sensitive volume by monoenergetic protons and alpha particles (with energies between 0.1 MeV and 20 MeV) were measured at the PTB ion accelerator facilities. C3H8 and N2 were alternately used as the working gas. The measured data were compared with the simulation results obtained with the PTB Monte-Carlo code PTra [B. Grosswendt, Radiat. Environ. Biophys. 41, 103 (2002); M.U. Bug, E. Gargioni, H. Nettelbeck, W.Y. Baek, G. Hilgers, A.B. Rosenfeld, H. Rabus, Phys. Rev. E 88, 043308 (2013)]. Measured and simulated characteristics of the particle track structure are generally in good agreement for protons over the entire energy range investigated. For alpha particles with energies higher than the Bragg peak energy, a good agreement can also be seen, whereas for energies lower than the Bragg peak energy differences of as much as 25% occur. Significant deviations are only observed for large ionisation cluster sizes. These deviations can be explained by a background consisting of secondary ions. These ions are produced in the

  18. Feasibility of matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS) networking in university hospitals in Brussels.

    Science.gov (United States)

    Martiny, D; Cremagnani, P; Gaillard, A; Miendje Deyi, V Y; Mascart, G; Ebraert, A; Attalibi, S; Dediste, A; Vandenberg, O

    2014-05-01

    The mutualisation of analytical platforms might be used to address rising healthcare costs. Our study aimed to evaluate the feasibility of networking a unique matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS) system for common use in several university hospitals in Brussels, Belgium. During a one-month period, 1,055 successive bacterial isolates from the Brugmann University Hospital were identified on-site using conventional techniques; these same isolates were also identified using a MALDI-TOF MS system at the Porte de Hal Laboratory by sending target plates and identification projects via transportation and the INFECTIO_MALDI software (Infopartner, Nancy, France), respectively. The occurrence of transmission problems (helpdesk to manage potential connectivity problems.

  19. Analysis of trace amounts of carbon dioxide, oxygen and carbon monoxide in nitrogen using dual capillary columns and a pulsed discharge helium ionisation detector.

    Science.gov (United States)

    Janse van Rensburg, M; Botha, A; Rohwer, E

    2007-10-01

    Gas mixtures of trace amounts of carbon dioxide (CO(2)), dioxygen (O(2)), and carbon monoxide (CO) in dinitrogen (N(2)) were separated and quantified using parallel dual capillary columns and pulsed discharge helium ionisation detection (PDHID). The detection limits (9 x 10(-9) mol mol(-1) for CO(2), 7 x 10(-9) mol mol(-1) for O(2) and 37 x 10(-9) mol mol(-1) for CO) were lower than those reported previously for similar methods. Uncertainties were calculated and results were validated by comparison of the CO and CO(2) results with those obtained using conventional methods. The method was also used to analyse nitrogen, carbon dioxide and carbon monoxide in oxygen. PMID:17765907

  20. Lactobacilli and ionising radiation: an example of the application to meat and meat products. Laktobazillen und ionisierende Strahlung als Beispiel einer Anwendung auf Fleisch und Fleischprodukte

    Energy Technology Data Exchange (ETDEWEB)

    Holzapfel, W.H. (Inst. fuer Hygiene und Toxikologie, Bundesforschungsanstalt fuer Ernaehrung, Karlsruhe (Germany))

    1992-01-01

    Ionising radiation provides a practical pasteurisation method for the terminal treatment of refrigerated vacuum-packaged meat products with the aim of shelf life extension. However, the relatively high radiation resistance ([gamma]-D[sub 10] = 0.70-1.2 kGy) of typical meat Lactobacilli, especially Lb. sake, selectively favours their total domination after treatments with 5 kGy. Typical meat strains show higher resistance (in term of [gamma]-D[sub 10] values the decimal reduction value due to irradiation) in the log (exponential) than in the stationary phase. This phenomenon was observed both in semi-synthetic broth and in meat, and may be explained in terms of a DNA repair mechanism operative during the exponential phase. Packaging under different gas atmospheres resulted in increased resistance to radiation in presence of N[sub 2], whilst the highest death rate was observed in presence of CO[sub 2]. (orig.)