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Sample records for 2001-2002 ionising radiation

  1. Solar Activity, Ultraviolet Radiation and Consequences in Birds in Mexico City, 2001- 2002

    NASA Astrophysics Data System (ADS)

    Valdes, M.; Velasco, V.

    2008-12-01

    Anomalous behavior in commercial and pet birds in Mexico City was reported during 2002 by veterinarians at the Universidad Nacional Autonoma de Mexico. This was attributed to variations in the surrounding luminosity. The solar components, direct, diffuse, global, ultraviolet band A and B, as well as some meteorological parameters, temperature, relative humidity, and precipitation, were then analyzed at the Solar Radiation Laboratory. Although the total annual radiance of the previously mentioned radiation components did not show important changes, ultraviolet Band-B solar radiation did vary significantly. During 2001 the total annual irradiance , 61.05 Hjcm² to 58.32 Hjcm², was 1.6 standard deviations lower than one year later, in 2002 and increased above the mean total annual irradiance, to 65.75 Hjcm², 2.04 standard deviations, giving a total of 3.73 standard deviations for 2001-2002. Since these differences did not show up clearly in the other solar radiation components, daily extra-atmosphere irradiance was analyzed and used to calculate the total annual extra-atmosphere irradiance, which showed a descent for 2001. Our conclusions imply that Ultraviolet Band-B solar radiation is representative of solar activity and has an important impact on commercial activity related with birds.

  2. Background ionising radiation: a pictorial perspective.

    PubMed

    Bibbo, Giovanni; Piotto, Lino

    2014-09-01

    Ionising radiation from natural sources, known as background radiation, has existed on earth since the earth's formation. The exposure of humans and other living creatures to this radiation is a feature of the earth's environment which is continuing and inescapable. The word "radiation" brings fear to many people: a fear of the unknown, as human's senses cannot detect the presence of ionising radiation. In this study, a catalogue of images of the distribution of radioactivity in every day objects and foods has been produced using an imaging plate from a computed radiography cassette. The aim of the study is that by visually demonstrating that every day objects and foods are radioactive would alleviate the fear of "radiation" by becoming aware that we live in a radioactive environment and even our body is radioactive.

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

    PubMed

    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. Copyright © 2015 International Agency for Research on Cancer. Published by Elsevier Ltd. All rights reserved.

  4. Dosimetry of ionising radiation in modern radiation oncology

    NASA Astrophysics Data System (ADS)

    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.

  5. Student Charges & Financial Aid, 2001-2002.

    ERIC Educational Resources Information Center

    National Association of State Universities and Land Grant Colleges, Washington, DC.

    Data from a variety of sources confirmed that the opening of the 2001-2002 academic year brought a return to reduced appropriations for higher education and higher tuition increases. As the impact of the continued economic slowdown and the financial blows from the September terrorist attacks become known, policymakers continue to reduce budgets…

  6. Infants and Toddlers, 2001-2002.

    ERIC Educational Resources Information Center

    Kroenke, Lillian DeVault, Ed.

    2002-01-01

    This document is comprised of the 2001-2002 issues of a quarterly journal for teachers and parents of children in Montessori infant and toddler programs. The spring 2001 issue presents articles on the history of infant and toddler programs in Italy and how to fulfill infant needs in Montessori child care, and on learning activities in the kitchen…

  7. IEC STANDARDS FOR INDIVIDUAL MONITORING OF IONISING RADIATION

    SciTech Connect

    Voytchev, Miroslav; Ambrosi, P.; Behrens, R.; Chiaro Jr, Peter John

    2011-01-01

    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.

  8. IEC standards for individual monitoring of ionising radiation.

    PubMed

    Voytchev, M; Ambrosi, P; Behrens, R; Chiaro, P

    2011-03-01

    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.

  9. Resonance laser-induced ionisation of sodium vapour taking radiative transfer into account

    SciTech Connect

    Kosarev, N I; Shaparev, N Ya

    2006-04-30

    The problem of ionisation of atomic sodium in the field of resonance laser radiation is numerically solved taking radiative transfer into account. Seed electrons are produced due to the mechanism of associative ionisation, then they gain energy in superelastic processes (collisions of the second kind) and initiate the avalanche ionisation of the medium by electron impact. We studied the effect of secondary radiation on the laser pulse propagation upon competition between the ionising and quenching electron collisions with excited atoms, on the kinetics of ionisation-induced vapour bleaching, and the plasma channel expansion in the form of a halo. (interaction of laser radiation with matter)

  10. Feedback regulated escape of ionising radiation from high redshift galaxies

    NASA Astrophysics Data System (ADS)

    Trebitsch, M.; Blaizot, J.

    2016-12-01

    Small galaxies are thought to provide the bulk of the radiation necessary to reionise the Universe by z ˜ 6. Their ionising efficiency is usually quantified by their escape fraction f_{esc}, but it is extremely hard to constrain from observations. With the goal of studying the physical processes that determine the values of the escape fraction, we have run a series of high resolution, cosmological, radiative hydrodynamics simulations centred on three galaxies. We find that the variability of the escape fraction follows that of the star formation rate, and that local feedback is necessary for radiation to escape.

  11. INTERACTION OF LASER RADIATION WITH MATTER: Resonance laser-induced ionisation of sodium vapour taking radiative transfer into account

    NASA Astrophysics Data System (ADS)

    Kosarev, N. I.; Shaparev, N. Ya

    2006-04-01

    The problem of ionisation of atomic sodium in the field of resonance laser radiation is numerically solved taking radiative transfer into account. Seed electrons are produced due to the mechanism of associative ionisation, then they gain energy in superelastic processes (collisions of the second kind) and initiate the avalanche ionisation of the medium by electron impact. We studied the effect of secondary radiation on the laser pulse propagation upon competition between the ionising and quenching electron collisions with excited atoms, on the kinetics of ionisation-induced vapour bleaching, and the plasma channel expansion in the form of a halo.

  12. Laboratory astrophysics experiments relating to ionising and weakly radiative shocks

    NASA Astrophysics Data System (ADS)

    Cross, Joseph; Foster, John; Graham, Peter; Busschaert, Clotilde; Charpentier, Nicolas; Danson, Colin; Doyle, Hugo; Drake, R. Paul; Falize, Emeric; Fyrth, Jim; Gumbrell, Edward; Koenig, Michel; Kuranz, Carolyn; Loupias, Berenice; Michaut, Claire; Patankar, Sid; Skidmore, Jonathan; Spindloe, Christopher; Tubman, Ellie; Woolsey, Nigel; Yurchak, Roman; Gregori, Gianluca

    2014-10-01

    The aim of the POLAR project is to simulate, in the laboratory, the accretion shock region of a magnetic cataclysmic variable binary star system. Scaling laws have shown that laser experiments can be related to astrophysical phenomena by matching relevant dimensionless parameters. As well as forming a reverse shock, relevant to the POLAR project, the experimental system is also likely formed of a weakly radiating shock and an ionisation front. Results from our experiment at the Orion Laser are presented here, alongside comparisons to simulation and the astrophysical case (of relevance to triggered star formation).

  13. Review of retrospective dosimetry techniques for external ionising radiation exposures.

    PubMed

    Ainsbury, E A; Bakhanova, E; Barquinero, J F; Brai, M; Chumak, V; Correcher, V; Darroudi, F; Fattibene, P; Gruel, G; Guclu, I; Horn, S; Jaworska, A; Kulka, U; Lindholm, C; Lloyd, D; Longo, A; Marrale, M; Monteiro Gil, O; Oestreicher, U; Pajic, J; Rakic, B; Romm, H; Trompier, F; Veronese, I; Voisin, P; Vral, A; Whitehouse, C A; Wieser, A; Woda, C; Wojcik, A; Rothkamm, K

    2011-11-01

    The current focus on networking and mutual assistance in the management of radiation accidents or incidents has demonstrated the importance of a joined-up approach in physical and biological dosimetry. To this end, the European Radiation Dosimetry Working Group 10 on 'Retrospective Dosimetry' has been set up by individuals from a wide range of disciplines across Europe. Here, established and emerging dosimetry methods are reviewed, which can be used immediately and retrospectively following external ionising radiation exposure. Endpoints and assays include dicentrics, translocations, premature chromosome condensation, micronuclei, somatic mutations, gene expression, electron paramagnetic resonance, thermoluminescence, optically stimulated luminescence, neutron activation, haematology, protein biomarkers and analytical dose reconstruction. Individual characteristics of these techniques, their limitations and potential for further development are reviewed, and their usefulness in specific exposure scenarios is discussed. Whilst no single technique fulfils the criteria of an ideal dosemeter, an integrated approach using multiple techniques tailored to the exposure scenario can cover most requirements.

  14. Binary-Encounter-Bethe ionisation cross sections for simulation of DNA damage by the direct effect of ionising radiation.

    PubMed

    Plante, I; Cucinotta, F A

    2015-09-01

    DNA damage is of crucial importance in the understanding of the effects of ionising radiation. To refine existing DNA damage models, an approach using the Binary-Encounter-Bethe (BEB) cross sections was developed. The differential cross sections for ionisation of the molecular orbitals of the DNA bases, sugars and phosphates are calculated using the electron binding energy, the mean kinetic energy and the occupancy number of each orbital as parameters. The resulting cross section has an analytic form which is quite convenient to use for Monte-Carlo codes that randomly sample the energy loss occurring during an ionisation event. We also describe an algorithm to simulate the interactions of electrons with DNA in the radiation transport code RITRACKS using the integrated BEB cross section for the bases, sugar and phosphates.

  15. International GPS Service 2001 - 2002 Technical Reports

    NASA Technical Reports Server (NTRS)

    Gowey, Ken (Editor); Neilan, Ruth (Editor); Moore, Angelyn (Editor)

    2004-01-01

    Applications of the Global Positioning System (GPS) to Earth Science are numerous. The International GPS Service (IGS), a federation of government agencies and universities, plays an increasingly critical role in support of GPS-related research and engineering activities. Contributions from the IGS Governing Board and Central Bureau, analysis and data centers, station operators, and others constitute the 2001 / 2002 Technical Reports. Hard copies of each volume can be obtained by contacting the IGS Central Bureau at the Jet Propulsion Laboratory. This report is published in black and white. To view graphs or plots that use color to represent data trends or information, please refer to the online PDF version at http://igscb.jpl.nasa.gov/overview/pubs.html.

  16. Hazards of ionising radiation: 100 years of observations on man.

    PubMed Central

    Doll, R.

    1995-01-01

    In November 1895, when Conrad Röntgen serendipitously discovered X-rays, epidemiology was effectively limited to the study of infectious disease. What little epidemiological work was done in other fields was done as part of clinical medicine or under the heading of geographical pathology. The risks from exposure to X-rays and subsequently from other types of ionising radiation were consequently discovered by qualitative association or animal experiment. They did not begin to be quantified in humans until half a century later, when epidemiology emerged as a scientific discipline capable of quantifying risks of non-infectious disease and the scientific world was alerted to the need for assessing the effects of the radiation to which large populations might be exposed by the use of nuclear energy in peace and war. PMID:8519643

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

    PubMed

    Oughton, Deborah

    2003-01-01

    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 environmental protection are discussed: First, the question of valuing the environment and implications for the definition of harm and monetary valuation of environmental goods; second, difficulties with scientific uncertainty and applications of the precautionary principle; and third, issues concerned with the distribution of risk and its relevance for participation in decision-making. In summary, the paper argues that there are strong ethical grounds 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. Copyright 2002 Elsevier Science Ltd.

  18. Migration levels of PVC plasticisers: Effect of ionising radiation treatment.

    PubMed

    Zygoura, Panagiota D; Paleologos, Evangelos K; Kontominas, Michael G

    2011-09-01

    Migration levels of commercial plasticisers [di-(2-ethylhexyl) adipate (DEHA) and acetyl tributyl citrate (ATBC)] from polyvinyl chloride (PVC) film into the EU specified aqueous food simulants (distilled water, 3% w/v acetic acid and 10% v/v ethanol) were monitored as a function of time. Migration testing was carried out at 40°C for 10days (EEC, 1993). Determination of the analytes was performed by applying the analytical methodology based on surfactant (Triton X-114) mediated extraction prior to gas chromatographic-flame ionisation detection (GC-FID) recently proposed by our group. The study focuses on the determination of the effect of gamma radiation on plasticiser migration into the selected simulants. PVC cling film used was subjected to ionising treatment with a [(60)Co] source at doses equal to 5, 15 and 25kGy. DEHA and ATBC migration into the EU aqueous simulating solvents was limited, yielding final concentrations in the respective ranges 10-100μg/l and 171-422μg/l; hence, ATBC demonstrated a stronger interaction with all three simulants compared to DEHA. Migration data, with respect to ATBC, showed that the most aggressive simulant seemed to be the 10% ethanol, while in the case of DEHA the 3% aqueous acetic acid exhibited the highest extraction efficiency; distilled water demonstrated the lowest migration in both cases. With regard to PVC treatment with gamma rays, high radiation doses up to 25kGy produced a statistically significant (p<0.05) effect on the migration of both plasticisers.

  19. Medical effects and risks of exposure to ionising radiation.

    PubMed

    Mettler, Fred A

    2012-03-01

    Effects and risk from exposure to ionising radiation depend upon the absorbed dose, dose rate, quality of radiation, specifics of the tissue irradiated and other factors such as the age of the individual. Effects may be apparent almost immediately or may take decades to be manifest. Cancer is the most important stochastic effect at absorbed doses of less than 1 Gy. The risk of cancer induction varies widely across different tissues; however, the risk of fatal radiation-induced cancer for a general population following chronic exposure is about 5% Sv(-1). Quantification of cancer risk at doses of less than 0.1 Gy remains problematic. Hereditary risks from irradiation that might result in effects to offspring of humans appear to be much lower and any such potential risks can only be estimated from animal models. At high doses (over 1 Gy) cell killing and modification causes deterministic effects such as skin burns, and bone marrow depression, in which case immunosuppression becomes a critical issue. Acute whole body penetrating gamma irradiation at doses in excess of 2 Gy results in varying degrees of acute radiation sickness and doses over 10 Gy are usually lethal as a result of combined organ injury.

  20. ER stress induced by ionising radiation in IEC-6 cells.

    PubMed

    Zhang, Bo; Wang, Yan; Pang, Xueli; Su, Yongping; Ai, Guoping; Wang, Tao

    2010-06-01

    Ionising radiation (IR) can evoke a series of biochemical events inside the cell. However, whether IR can directly induce endoplasmic reticulum (ER) stress is not clear. In our previous study, we found that there might be a causative link between IR and ER stress. In this study, we further characterised the type of ER stress induced by IR. Rat intestinal epithelial cells IEC-6 were irradiated at a dose of 10 Gy, and total RNA and proteins were harvested at indicated time points. The mRNA and protein expression of immunoglobulin heavy chain binding protein (BiP) and glucose regulated protein 94 (GRP94) was detected along with proteins associated with ER stress signal pathways. Our results indicated that IR induced up-regulation of ER stress marker including BiP and GRP94 at protein and mRNA levels in IEC-6 cells. Increased phosphorylation of eukaryotic translation initiation factor 2 (eIF2alpha) and induced mRNA splicing of X-box binding protein 1 (XBP1) suggested that PERK (interferon-induced double-stranded RNA-activated protein kinase (PRKR) -like endoplasmic reticulum kinase) and IRE1 (inositol requirement 1) signal transduction pathways were involved in this kind of ER stress. However, the active form of activating transcription factor 6 (ATF6) did not change significantly in irradiated cells, which suggested that the ATF6 pathway was not involved. Thus, we concluded that IR could induce moderate ER stress directly in IEC-6 cells.

  1. The New 2001-2002 Term. Supreme Court Roundup.

    ERIC Educational Resources Information Center

    Williams, Charles F.

    2001-01-01

    Discusses the issues addressed during the 2001-2002 term of the U.S. Supreme Court, which convened on October 1, 2001: (1) school vouchers; (2) affirmative action; (3) online pornography; and (4) the death penalty. (CMK)

  2. The New 2001-2002 Term. Supreme Court Roundup.

    ERIC Educational Resources Information Center

    Williams, Charles F.

    2001-01-01

    Discusses the issues addressed during the 2001-2002 term of the U.S. Supreme Court, which convened on October 1, 2001: (1) school vouchers; (2) affirmative action; (3) online pornography; and (4) the death penalty. (CMK)

  3. St. Petersburg College FactBook, 2001-2002.

    ERIC Educational Resources Information Center

    Saint Petersburg Junior Coll., FL. Office of Institutional Research.

    This 2001-2002 fact book for St. Petersburg College (SPC) in Florida provides statistical information to support planning and decision-making. It also offers a historical perspective of the institution. SPC was founded in 1927 as St. Petersburg Junior College, Florida's first two-year institution of higher learning. SPC has evolved from an…

  4. The State of Our Nation's Youth, 2001-2002.

    ERIC Educational Resources Information Center

    Horatio Alger Association of Distinguished Americans, Inc., Alexandria, VA.

    This report details 2001-2002 findings of an annual, national survey of the attitudes and plans of American adolescents. Participating in the telephone survey was a nationally representative sample of 1,014 students 13 to 18 years of age in ninth through twelfth grade. The report summarizes findings "at a glance" and discusses findings under the…

  5. Colorado Even Start Progress Report, 2001-2002.

    ERIC Educational Resources Information Center

    Anderson, Beckie

    Even Start programs integrate early childhood education, adult literacy or basic education, parenting education and support, and parent and child time together to help break the cycle of poverty and illiteracy. This progress report describes the Even Start program in Colorado and presents evaluation findings from the 2001-2002 implementation year,…

  6. Foundation for Child Development Annual Report, 2001-2002.

    ERIC Educational Resources Information Center

    Foundation for Child Development, New York, NY.

    This annual report details the activities of the Foundation for Child Development (FCD) for 2001-2002. Beginning the report is a brief description of the Foundations mission, its funding priorities, and application procedures. The report then presents the joint statement of the chair, Karen Gerard, and the president, Ruby Takanishi, focusing on…

  7. Student and intern awareness of ionising radiation exposure from common diagnostic imaging procedures.

    PubMed

    Zhou, G Z; Wong, D D; Nguyen, L K; Mendelson, R M

    2010-02-01

    This study aims to evaluate medical student and intern awareness of ionising radiation exposure from common diagnostic imaging procedures and to suggest how education could be improved. Fourth to sixth year medical students enrolled at a Western Australian university and interns from three teaching hospitals in Perth were recruited. Participants were asked to complete a questionnaire consisting of 26 questions on their background, knowledge of ionising radiation doses and learning preferences for future teaching on this subject. A total of 331 completed questionnaires were received (95.9%). Of the 17 questions assessing knowledge of ionising radiation, a mean score of 6.0 was obtained by respondents (95% CI 5.8-6.2). Up to 54.8% of respondents underestimated the radiation dose from commonly requested radiological procedures. Respondents (11.3 and 25.5%) incorrectly believed that ultrasound and MRI emit ionising radiation, respectively. Of the four subgroups of respondents, the intern doctor subgroup performed significantly better (mean score 6.9, P < 0.0001, 95% CI 6.5-7.3) than each of the three medical student subgroups. When asked for the preferred method of teaching for future radiation awareness, a combination of lectures, tutorials and workshops was preferred. This study has clearly shown that awareness of ionising radiation from diagnostic imaging is lacking among senior medical students and interns. The results highlight the need for improved education to minimise unnecessary exposure of patients and the community to radiation. Further studies are required to determine the most effective form of education.

  8. The impact of high and low dose ionising radiation on the central nervous system.

    PubMed

    Betlazar, Calina; Middleton, Ryan J; Banati, Richard B; Liu, Guo-Jun

    2016-10-01

    Responses of the central nervous system (CNS) to stressors and injuries, such as ionising radiation, are modulated by the concomitant responses of the brains innate immune effector cells, microglia. Exposure to high doses of ionising radiation in brain tissue leads to the expression and release of biochemical mediators of 'neuroinflammation', such as pro-inflammatory cytokines and reactive oxygen species (ROS), leading to tissue destruction. Contrastingly, low dose ionising radiation may reduce vulnerability to subsequent exposure of ionising radiation, largely through the stimulation of adaptive responses, such as antioxidant defences. These disparate responses may be reflective of non-linear differential microglial activation at low and high doses, manifesting as an anti-inflammatory or pro-inflammatory functional state. Biomarkers of pathology in the brain, such as the mitochondrial Translocator Protein 18kDa (TSPO), have facilitated in vivo characterisation of microglial activation and 'neuroinflammation' in many pathological states of the CNS, though the exact function of TSPO in these responses remains elusive. Based on the known responsiveness of TSPO expression to a wide range of noxious stimuli, we discuss TSPO as a potential biomarker of radiation-induced effects.

  9. The Effects of Ionising Radiation on MEMS Silicon Strain Gauges: Preliminary Background and Methodology

    DTIC Science & Technology

    2006-09-01

    tuneable radar, structural health monitoring (corrosion and strain sensing) and power production . 2. Ionising Radiation Susceptibility of...materials this displacement damage affects the electronic energy states, which can give rise to several processes, including increased thermal ...are smaller and lighter than the current generation of detectors. The lower costs associated with mass- production of MEMS could also allow greater

  10. For discussion: obtaining consent for ionising radiation: has the time come?

    PubMed

    Mendelson, Richard M

    2010-10-01

    The aim of this paper is to promote debate on the issues surrounding the provision of information to, and the obtaining of valid consent from patients exposed to ionising radiation (IR) from diagnostic and interventional imaging procedures. This is especially pertinent in view of recent interest in the risks of IR expressed in the medical and lay press.

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

    PubMed

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

    PubMed

    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.

  13. 76 FR 7590 - Distribution of 2000, 2001, 2002, and 2003 Cable Royalty Funds

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-10

    ... Copyright Royalty Board Distribution of 2000, 2001, 2002, and 2003 Cable Royalty Funds AGENCY: Copyright... commencement of a proceeding to determine the Phase II distribution of 2000, 2001, 2002, and 2003 royalties... cable royalties collected for 2000, 2001, 2002, and 2003 is confined to Phase II. Commencement of...

  14. Teaching about Radioactivity and Ionising Radiation: An Alternative Approach.

    ERIC Educational Resources Information Center

    Millar, Robin; And Others

    1990-01-01

    Children's ideas about radiation and radioactivity are reviewed and several common areas of misunderstanding are identified. An approach to teaching the topic at the secondary school level which seeks to specifically address known difficulties is outlined. (CW)

  15. EURADOS strategic research agenda: vision for dosimetry of ionising radiation

    PubMed Central

    Rühm, W.; Fantuzzi, E.; Harrison, R.; Schuhmacher, H.; Vanhavere, F.; Alves, J.; Bottollier Depois, J. F.; Fattibene, P.; Knežević, Ž.; Lopez, M. A.; Mayer, S.; Miljanić, S.; Neumaier, S.; Olko, P.; Stadtmann, H.; Tanner, R.; Woda, C.

    2016-01-01

    Since autumn 2012, the European Radiation Dosimetry Group (EURADOS) has been developing its Strategic Research Agenda (SRA), which is intended to contribute to the identification of future research needs in radiation dosimetry in Europe. The present article summarises—based on input from EURADOS Working Groups (WGs) and Voting Members—five visions in dosimetry and defines key issues in dosimetry research that are considered important for the next decades. The five visions include scientific developments required towards (a) updated fundamental dose concepts and quantities, (b) improved radiation risk estimates deduced from epidemiological cohorts, (c) efficient dose assessment for radiological emergencies, (d) integrated personalised dosimetry in medical applications and (e) improved radiation protection of workers and the public. The SRA of EURADOS will be used as a guideline for future activities of the EURADOS WGs. A detailed version of the SRA can be downloaded as a EURADOS report from the EURADOS website (www.eurados.org). PMID:25752758

  16. Teaching about Radioactivity and Ionising Radiation: An Alternative Approach.

    ERIC Educational Resources Information Center

    Millar, Robin; And Others

    1990-01-01

    Children's ideas about radiation and radioactivity are reviewed and several common areas of misunderstanding are identified. An approach to teaching the topic at the secondary school level which seeks to specifically address known difficulties is outlined. (CW)

  17. Occupational exposure to ionising radiation and mortality among workers of the former Spanish Nuclear Energy Board.

    PubMed Central

    Rodríguez Artalejo, F; Castaño Lara, S; de Andrés Manzano, B; García Ferruelo, M; Iglesias Martín, L; Calero, J R

    1997-01-01

    OBJECTIVES: Firstly, to ascertain whether mortality among workers of the former Spanish Nuclear Energy Board (Junta de Energía Nuclear-JEN) was higher than that for the Spanish population overall; and secondly, if this were so, to ascertain whether this difference was associated with exposure to ionising radiation. METHODS: A retrospective follow up of a cohort of 5657 workers was carried out for the period 1954-92. Cohort mortality was compared with that for the Spanish population overall, with standardised mortality ratios (SMRs) adjusted for sex, age, and calendar period. Also, Poisson models were used to analyse mortality from lung cancer in the cohort by level of exposure to ionising radiation. RESULTS: Workers' median and mean cumulative exposures were 4.04 and 11.42 mSv, respectively. Mean annual exposure was 1.33 mSv. Excess mortality due to bone tumours was found for the cohort as a whole (six deaths observed; SMR 2.95; 95% confidence interval (95% CI) 1.08 to 6.43). Among miners, excess mortality was found for non-malignant respiratory diseases (SMR 2.94; 95% CI 2.27 to 3.75), and for lung cancer bordering on statistical significance (SMR 1.50; 95% CI 0.96 to 2.23; P = 0.055). Relative risks of dying of lung cancer from ionising radiation in the dose quartiles 2, 3, and 4 versus the lowest dose quartile, were 1.00, 1.64, and 0.94, respectively. CONCLUSIONS: Excess mortality from lung cancer was found among JEN miners. Nevertheless, no clear relation was found between mortality from lung cancer and level of exposure to ionising radiation in the JEN cohort. Continued follow up of the cohort is required to confirm excess mortality from bone tumours. PMID:9155782

  18. Occupational exposure to ionising radiation and mortality among workers of the former Spanish Nuclear Energy Board.

    PubMed

    Rodríguez Artalejo, F; Castaño Lara, S; de Andrés Manzano, B; García Ferruelo, M; Iglesias Martín, L; Calero, J R

    1997-03-01

    Firstly, to ascertain whether mortality among workers of the former Spanish Nuclear Energy Board (Junta de Energía Nuclear-JEN) was higher than that for the Spanish population overall; and secondly, if this were so, to ascertain whether this difference was associated with exposure to ionising radiation. A retrospective follow up of a cohort of 5657 workers was carried out for the period 1954-92. Cohort mortality was compared with that for the Spanish population overall, with standardised mortality ratios (SMRs) adjusted for sex, age, and calendar period. Also, Poisson models were used to analyse mortality from lung cancer in the cohort by level of exposure to ionising radiation. Workers' median and mean cumulative exposures were 4.04 and 11.42 mSv, respectively. Mean annual exposure was 1.33 mSv. Excess mortality due to bone tumours was found for the cohort as a whole (six deaths observed; SMR 2.95; 95% confidence interval (95% CI) 1.08 to 6.43). Among miners, excess mortality was found for non-malignant respiratory diseases (SMR 2.94; 95% CI 2.27 to 3.75), and for lung cancer bordering on statistical significance (SMR 1.50; 95% CI 0.96 to 2.23; P = 0.055). Relative risks of dying of lung cancer from ionising radiation in the dose quartiles 2, 3, and 4 versus the lowest dose quartile, were 1.00, 1.64, and 0.94, respectively. Excess mortality from lung cancer was found among JEN miners. Nevertheless, no clear relation was found between mortality from lung cancer and level of exposure to ionising radiation in the JEN cohort. Continued follow up of the cohort is required to confirm excess mortality from bone tumours.

  19. The biological effects of ionising radiation on Crustaceans: A review.

    PubMed

    Fuller, Neil; Lerebours, Adélaïde; Smith, Jim T; Ford, Alex T

    2015-10-01

    Historic approaches to radiation protection are founded on the conjecture that measures to safeguard humans are adequate to protect non-human organisms. This view is disparate with other toxicants wherein well-developed frameworks exist to minimise exposure of biota. Significant data gaps for many organisms, coupled with high profile nuclear incidents such as Chernobyl and Fukushima, have prompted the re-evaluation of our approach toward environmental radioprotection. Elucidating the impacts of radiation on biota has been identified as priority area for future research within both scientific and regulatory communities. The crustaceans are ubiquitous in aquatic ecosystems, comprising greater than 66,000 species of ecological and commercial importance. This paper aims to assess the available literature of radiation-induced effects within this subphylum and identify knowledge gaps. A literature search was conducted pertaining to radiation effects on four endpoints as stipulated by a number of regulatory bodies: mortality, morbidity, reproduction and mutation. A major finding of this review was the paucity of data regarding the effects of environmentally relevant radiation doses on crustacean biology. Extremely few studies utilising chronic exposure durations or wild populations were found across all four endpoints. The dose levels at which effects occur was found to vary by orders of magnitude thus presenting difficulties in developing phyla-specific benchmark values and reference levels for radioprotection. Based on the limited data, mutation was found to be the most sensitive endpoint of radiation exposure, with mortality the least sensitive. Current phyla-specific dose levels and limits proposed by major regulatory bodies were found to be inadequate to protect species across a range of endpoints including morbidity, mutation and reproduction and examples are discussed within. These findings serve to prioritise areas for future research that will significantly

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

    NASA Astrophysics Data System (ADS)

    Dartnell, L. R.; Desorgher, L.; Ward, J. M.; Coates, A. J.

    2007-02-01

    The surface of Mars, unshielded by thick atmosphere or global magnetic field, is exposed to high levels of cosmic radiation. This ionizing 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. Previous research has attempted to address the question of biomarker persistence by inappropriately using dose profiles weighted specifically for cellular survival. Here, we present modelling results of the unmodified physically absorbed radiation dose as a function of depth through the Martian subsurface. 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 from galactic cosmic rays 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 briefly treat particle deflection by the crustal magnetic fields.

  1. How do air ions reflect variations in ionising radiation in the lower atmosphere in a boreal forest?

    NASA Astrophysics Data System (ADS)

    Chen, Xuemeng; Kerminen, Veli-Matti; Paatero, Jussi; Paasonen, Pauli; Manninen, Hanna E.; Nieminen, Tuomo; Petäjä, Tuukka; Kulmala, Markku

    2016-11-01

    Most of the ion production in the atmosphere is attributed to ionising radiation. In the lower atmosphere, ionising radiation consists mainly of the decay emissions of radon and its progeny, gamma radiation of the terrestrial origin as well as photons and elementary particles of cosmic radiation. These types of radiation produce ion pairs via the ionisation of nitrogen and oxygen as well as trace species in the atmosphere, the rate of which is defined as the ionising capacity. Larger air ions are produced out of the initial charge carriers by processes such as clustering or attachment to pre-existing aerosol particles. This study aimed (1) to identify the key factors responsible for the variability in ionising radiation and in the observed air ion concentrations, (2) to reveal the linkage between them and (3) to provide an in-depth analysis into the effects of ionising radiation on air ion formation, based on measurement data collected during 2003-2006 from a boreal forest site in southern Finland. In general, gamma radiation dominated the ion production in the lower atmosphere. Variations in the ionising capacity came from mixing layer dynamics, soil type and moisture content, meteorological conditions, long-distance transportation, snow cover attenuation and precipitation. Slightly similar diurnal patterns to variations in the ionising capacity were observed in air ion concentrations of the cluster size (0.8-1.7 nm in mobility diameters). However, features observed in the 0.8-1 nm ion concentration were in good connection to variations of the ionising capacity. Further, by carefully constraining perturbing variables, a strong dependency of the cluster ion concentration on the ionising capacity was identified, proving the functionality of ionising radiation in air ion production in the lower atmosphere. This relationship, however, was only clearly observed on new particle formation (NPF) days, possibly indicating that charges after being born underwent different

  2. Comparison of low and high dose ionising radiation using topological analysis of gene coexpression networks.

    PubMed

    Ray, Monika; Yunis, Reem; Chen, Xiucui; Rocke, David M

    2012-05-17

    The growing use of imaging procedures in medicine has raised concerns about exposure to low-dose ionising radiation (LDIR). While the disastrous effects of high dose ionising radiation (HDIR) is well documented, the detrimental effects of LDIR is not well understood and has been a topic of much debate. Since little is known about the effects of LDIR, various kinds of wet-lab and computational analyses are required to advance knowledge in this domain. In this paper we carry out an "upside-down pyramid" form of systems biology analysis of microarray data. We characterised the global genomic response following 10 cGy (low dose) and 100 cGy (high dose) doses of X-ray ionising radiation at four time points by analysing the topology of gene coexpression networks. This study includes a rich experimental design and state-of-the-art computational systems biology methods of analysis to study the differences in the transcriptional response of skin cells exposed to low and high doses of radiation. Using this method we found important genes that have been linked to immune response, cell survival and apoptosis. Furthermore, we also were able to identify genes such as BRCA1, ABCA1, TNFRSF1B, MLLT11 that have been associated with various types of cancers. We were also able to detect many genes known to be associated with various medical conditions. Our method of applying network topological differences can aid in identifying the differences among similar (eg: radiation effect) yet very different biological conditions (eg: different dose and time) to generate testable hypotheses. This is the first study where a network level analysis was performed across two different radiation doses at various time points, thereby illustrating changes in the cellular response over time.

  3. Comparison of low and high dose ionising radiation using topological analysis of gene coexpression networks

    PubMed Central

    2012-01-01

    Background The growing use of imaging procedures in medicine has raised concerns about exposure to low-dose ionising radiation (LDIR). While the disastrous effects of high dose ionising radiation (HDIR) is well documented, the detrimental effects of LDIR is not well understood and has been a topic of much debate. Since little is known about the effects of LDIR, various kinds of wet-lab and computational analyses are required to advance knowledge in this domain. In this paper we carry out an “upside-down pyramid” form of systems biology analysis of microarray data. We characterised the global genomic response following 10 cGy (low dose) and 100 cGy (high dose) doses of X-ray ionising radiation at four time points by analysing the topology of gene coexpression networks. This study includes a rich experimental design and state-of-the-art computational systems biology methods of analysis to study the differences in the transcriptional response of skin cells exposed to low and high doses of radiation. Results Using this method we found important genes that have been linked to immune response, cell survival and apoptosis. Furthermore, we also were able to identify genes such as BRCA1, ABCA1, TNFRSF1B, MLLT11 that have been associated with various types of cancers. We were also able to detect many genes known to be associated with various medical conditions. Conclusions Our method of applying network topological differences can aid in identifying the differences among similar (eg: radiation effect) yet very different biological conditions (eg: different dose and time) to generate testable hypotheses. This is the first study where a network level analysis was performed across two different radiation doses at various time points, thereby illustrating changes in the cellular response over time. PMID:22594378

  4. Cytogenetic monitoring of nuclear workers occupationally exposed to ionising radiation.

    PubMed

    Gricienė, B; Slapšytė, G; Mierauskienė, J

    2014-06-01

    Chromosome aberration (CA) analysis using Giemsa techniques was performed in blood lymphocytes of 84 nuclear workers with cumulative doses of 1-632 mSv during employment periods of 1-25 y. The control group comprised 82 healthy male donors. An estimated CA frequency in the total radiation-exposed group was significantly higher when compared with the controls (2.27 vs. 1.76 CA/100 cells, p < 0.05). CA analyses revealed no significant differences between workers with external gamma radiation exposure and the controls (1.60 vs. 1.76 CA/100 cells, p > 0.05). However, significant increase in the total CA frequency was determined in workers with additional internal exposure (2.54 CA/100 cells, p < 0.05) and those with registered neutron doses (2.95 CA/100 cells, p < 0.01). No correlation was found between CA frequency and occupational exposure dose. Borderline significant correlation was found between duration of employment and total CA (r = 0.218, p = 0.046, Fig. 2) and chromosome-type aberration (r = 0.265, p = 0.015) frequency.

  5. Current trends in estimating risk of cancer from exposure to low doses of ionising radiation.

    PubMed

    Majer, Marija; Knežević, Zeljka; Saveta, Miljanić

    2014-09-29

    Although ionising radiation has proven beneficial in the diagnosis and therapy of a number of diseases, one should keep in mind that irradiating healthy tissue may increase the risk of cancer. In order to justify an exposure to radiation, both the benefits and the risks must be evaluated and compared. The deleterious effects of medium and high doses are well known, but it is much less clear what effects arise from low doses (below 0.1 Gy), which is why such risk estimates are extremely important. This review presents the current state, important assumptions and steps being made in deriving cancer risk estimates for low dose exposures.

  6. EVOLUTION OF THE IEC AND EN STANDARDS FOR INDIVIDUAL MONITORING OF IONISING RADIATION.

    PubMed

    Voytchev, M; Behrens, R; Ambrosi, P; Radev, R; Chiaro, P

    2016-09-01

    This article presents the evolution of the International Electrotechnical Commission (IEC) and the European standards for individual monitoring of ionising radiation issued, respectively, from the committees IEC/Sub Committee 45B and European Committee for Electro-technical Standardization/Technical Committee 45B 'Radiation protection instrumentation'. Standards for passive individual photon and beta dosimetry systems as well as those for active individual monitors are discussed. A neutron ambient dose equivalent (rate) meter standard and a technical report concerning the determination of uncertainty in measurement are also covered. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  7. Ionising radiation triggers fat accumulation in white adipose tissue.

    PubMed

    Jo, Sung Kee; Seol, Min-A; Park, Hae-Ran; Jung, Uhee; Roh, Changhyun

    2011-03-01

    To investigate changes in gonadal white adipose tissue and lipogenesis-related gene expression induced by radiation exposure. Groups of two-month-old C57BL/6 mice were exposed whole-body to ¹³⁷Cs γ-rays at a single dose (5 gray [Gy]) or fractionated doses (1 Gy x 5 times, 0.5 Gy x 10 times, or 0.2 Gy x 25 times). Six months after irradiation, gonadal white adipose tissue was isolated from mice. Two and 25-month-old mice were used as young and old study references. Real-time reverse transcriptase-polymerase chain reaction (RT-PCR) was used to measure messenger RNA (mRNA) expression of genes related to: (i) Primary lipid metabolism (ATP-citrate lyase [ACL], malic enzyme1 [ME1] and glucose-6-phosphate dehydrogenase 2 [G6PD2]), (ii) glucose uptake (glucose transporter 4 [GLUT4]), (iii) fatty acid synthesis (sterol regulatory element binding transcription factor 1 [SREBP-1c], fatty acid synthetase [FAS] and acetyl-coenzyme A carboxylase beta [ACC]), (iv) triglyceride synthesis (diacylglycerol O-acyltransferase 1 [DGAT1] and diacylglycerol O-acyltransferase 2 [DGAT2]), and (v) adipose-derived hormones (leptin [LEP]). The weight of gonadal white adipose tissue in the irradiated groups tended to increase compared to the non-irradiated group though the radiation-induced increase in white adipose tissue was only significant for the 5 x 1 Gy group. The mRNA levels of SREBP-1c, ACC, FAS, ACL, GLUT4, ME1 and G6PD2 were relatively lower in γ-irradiated groups than in non-irradiated groups. The mRNA levels of leptin and DGAT were relatively higher than non-irradiated groups. The changes in expression of these lipogenesis-related genes caused by γ-irradiation showed a very similar pattern to changes caused by ageing. A physical agent such as γ-rays can trigger biological responses resulting in fat accumulation of gonadal white adipose tissue in mice.

  8. Non-ionising radiation human exposure assessment near telecommunication devices in Croatia.

    PubMed

    Simunić, Dina

    2006-03-01

    This paper gives an overview of the regulatory acts in non-ionising radiation in the world, with a special emphasis on basic guidelines issued by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). ICNIRP Guidelines are implemented in many countries worldwide. Croatia has also implemented them indirectly through the European Recommendation 1999/519/EC. The Croatian regulatory acts include the Non-lonising Radiation Protection Act, Ordinance on Electromagnetic Fields (EMF) Protection, and the Ordinance on Basic Requirements for Devices which produce Optical Radiation and Measures for Optical Radiation Protection. Dosimetry and densitometry are compliant with relevant international and European standards. The paper presents an example of densitometric human exposure assessment in complex indoor exposure conditions. In spite of a high number of indoor and outdoor sources and the "worst-case exposure assessment", the results are within the limits defined by the Croatian EMF Ordinance.

  9. Water Science and Technology Board Annual Report 2001-2002

    SciTech Connect

    2002-10-01

    This annual report marks the twentieth anniversary of the Water Science and Technology Board (WSTB) (1982-2002). The WSTB oversees studies of water issues. The principal products of studies are written reports. These reports cover a wide range of water resources issues of national concern. The following three recently issued reports illustrate the scope of the WSTB's studies: Envisioning the Agenda for Water Resources Research in the Twenty-first Century. The Missouri River Ecosystem: Exploring the Prospects for Recovery, and Assessing the TMDL Approach to Water Quality Management. The WSTB generally meets three times each year where discussions are held on ongoing projects, strategic planning, and developing new initiatives. The meetings also foster communication within the water resources community. The annual report includes a discussion on current studies, completed studies 2001-2002, and future plans, as well as a listing of published reports (1983-2002).

  10. Noodle consumption patterns of American consumers: NHANES 2001-2002

    PubMed Central

    Chung, Chin Eun; Lee, Kyung Won

    2010-01-01

    Although noodles occupy an important place in the dietary lives of Americans, up until the present time research and in-depth data on the noodle consumption patterns of the US population have been very limited. Therefore, this study aimed to analyze the food consumption and diet patterns of noodle consumers and non-consumers according to age, gender, income, and ethnicity. The 2001-2002 NHANES databases were used. The NHANES 2001-2002 data showed that noodle consumers reporting noodle consumption in their 24-h recall were 2,035 individuals (23.3% of total subjects). According to the results, the mean noodle consumption was 304.1 g/day/person, with 334.3 g for males and 268.0 g for females. By age, the intake of those in the age range of 9-18 years old ranked highest at 353.0 g, followed by the order of 19-50 year-olds with 333.5 g, 51-70 year-olds with by 280.4 g, older than 71years old with 252.3 g, and 1-8 year-olds with 221.5 g. By gender, males consumed more noodles than females. Also, according to income, the intake amount for the middle-income level (PIR 1~1.85) of consumers was highest at 312.5 g. Noodle intake also showed different patterns by ethnicity in which the "other" ethnic group consumed the most noodles with 366.1 g, followed by, in order, Hispanics with 318.7 g, Whites with 298.6 g, and Blacks with 289.5 g. After comparing food consumption by dividing the subjects into noodle consumers and non-consumers, the former was more likely to consume milk, fish, citrus fruits, tomatoes, and alcoholic beverages while the latter preferred meat, poultry, bread, and non-alcohol beverages. PMID:20607071

  11. Noodle consumption patterns of American consumers: NHANES 2001-2002.

    PubMed

    Chung, Chin Eun; Lee, Kyung Won; Cho, Mi Sook

    2010-06-01

    Although noodles occupy an important place in the dietary lives of Americans, up until the present time research and in-depth data on the noodle consumption patterns of the US population have been very limited. Therefore, this study aimed to analyze the food consumption and diet patterns of noodle consumers and non-consumers according to age, gender, income, and ethnicity. The 2001-2002 NHANES databases were used. The NHANES 2001-2002 data showed that noodle consumers reporting noodle consumption in their 24-h recall were 2,035 individuals (23.3% of total subjects). According to the results, the mean noodle consumption was 304.1 g/day/person, with 334.3 g for males and 268.0 g for females. By age, the intake of those in the age range of 9-18 years old ranked highest at 353.0 g, followed by the order of 19-50 year-olds with 333.5 g, 51-70 year-olds with by 280.4 g, older than 71years old with 252.3 g, and 1-8 year-olds with 221.5 g. By gender, males consumed more noodles than females. Also, according to income, the intake amount for the middle-income level (PIR 1~1.85) of consumers was highest at 312.5 g. Noodle intake also showed different patterns by ethnicity in which the "other" ethnic group consumed the most noodles with 366.1 g, followed by, in order, Hispanics with 318.7 g, Whites with 298.6 g, and Blacks with 289.5 g. After comparing food consumption by dividing the subjects into noodle consumers and non-consumers, the former was more likely to consume milk, fish, citrus fruits, tomatoes, and alcoholic beverages while the latter preferred meat, poultry, bread, and non-alcohol beverages.

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

    PubMed

    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.

  13. The effect of non ionising electromagnetic radiation on RAAF personnel during World War II.

    PubMed

    Flaherty, J A

    1994-05-01

    Did exposure to non ionising electromagnetic radiation during World War II in the short term have a stimulating effect on the anterior pituitary gland, and in turn on the gonads of both sexes, since the figures obtained appeared to affect the sexes equally? Is it that the long-term effect of microwave radiation on personnel is to cause adenoma and carcinoma? Is this long-term effect similar to the long-term effect of X-rays on infants, children and adolescents? According to Harrison's Principles of Internal Medicine 1980 (page 1710): "X-rays to the head and neck in infancy, childhood or adolescence is associated with a high incidence of thyroid disease later in life. Nodular disease is found to be particularly common on 20% of patients at risk, and may not be apparent until 30 years or more after exposure. One-third of the nodular type are found to be carcinomatous." The effect of non ionising electromagnetic and microwave radiation on those who work in these fields certainly needs much more investigation. What will be the long-term effect of using micro-ovens on the rising generation?

  14. Adaptive response to ionising radiation induced by cadmium in zebrafish embryos.

    PubMed

    Choi, V W Y; Ng, C Y P; Kong, M K Y; Cheng, S H; Yu, K N

    2013-03-01

    An adaptive response is a biological response where the exposure of cells or animals to a low priming exposure induces mechanisms that protect the cells or animals against the detrimental effects of a subsequent larger challenging exposure. In realistic environmental situations, living organisms can be exposed to a mixture of stressors, and the resultant effects due to such exposures are referred to as multiple stressor effects. In the present work we demonstrated, via quantification of apoptosis in the embryos, that embryos of the zebrafish (Danio rerio) subjected to a priming exposure provided by one environmental stressor (cadmium in micromolar concentrations) could undergo an adaptive response against a subsequent challenging exposure provided by another environmental stressor (alpha particles). We concluded that zebrafish embryos treated with 1 to 10 μM Cd at 5 h postfertilisation (hpf) for both 1 and 5 h could undergo an adaptive response against subsequent ~4.4 mGy alpha-particle irradiation at 10 hpf, which could be interpreted as an antagonistic multiple stressor effect between Cd and ionising radiation. The zebrafish has become a popular vertebrate model for studying the in vivo response to ionising radiation. As such, our results suggested that multiple stressor effects should be carefully considered for human radiation risk assessment since the risk may be perturbed by another environmental stressor such as a heavy metal.

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

    NASA Astrophysics Data System (ADS)

    Dartnell, Lewis R.

    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 this radiation on Mars. A sophisticated computer model has been constructed de novo to characterise this complex subsurface ionising radiation field and explore the influence of variation in crucial parameters such as atmospheric density, surface composition, and primary radiation spectra. Microbiological work has been conducted to isolate novel cold-tolerant bacterial strains from the Dry Valleys environment of Antarctica, an analogue site to the martian surface, and determine their phylogenetic diversity and survival under high-dose gamma-ray exposure frozen at -79 °C, a temperature characteristic of the martian mid-latitude permafrost. Original results are presented pertinent to microbial survival time, persistence of organic biomarkers, and calibration of the optically stimulated luminescence dating technique, as a function of depth. The model predicts a population of radiation resistant cells to survive in martian permafrost soil for 450,000 years at 2 m depth, the proposed drill length of the ExoMars rover. The Antarctic culturing studies identified representatives of four bacterial genera. The novel isolate Brevundimonas sp. MV.7 is found to show 99% 16S sequence similarity to cells discovered in NASA spacecraft assembly clean rooms, with the experimental irradiation determining this strain to suffer 10-6 population inactivation after a radiation dose of 7.5 kGy in martian permafrost conditions. Integrating the modelling and experimental irradiation, this research finds a contaminant

  16. Characterisation of PRESAGE: A new 3-D radiochromic solid polymer dosemeter for ionising radiation.

    PubMed

    Adamovics, J; Maryanski, M J

    2006-01-01

    For the past 50 years there has been interest in developing 3-D dosemeters for ionising radiation. Particular emphasis has been put on those dosemeters that change their optical properties in proportion to the absorbed dose. Many of the dosemeters that have been evaluated have had limitations such as lack of transparency, diffusion of the image of the dose distribution or poor stability of baseline optical density. Many of these performance limitations have been overcome by the development of PRESAGE, an optically clear polyurethane-based radiochromic 3-D dosemeter. The solid PRESAGE dosemeter is formulated with a free radical initiator and a leuco dye and it does not require a container to maintain its shape. The polyurethane matrix is tissue equivalent and prevents the diffusion of the dose distribution image. There is a linear dose-response, which is independent of both photon energy and dose rate. Simple precautions such as preventing long-term exposure to additional ionising radiation including ultraviolet and controlling storage temperatures prevent the bleaching of the radiochromic response field within the irradiated dosemeter.

  17. Ionisation response in semiconductor structures exposed to the X-ray radiation of a femtosecond laser-plasma source

    NASA Astrophysics Data System (ADS)

    Chumakov, A. I.; Belova, M. P.; Kessarinsky, L. N.; Borisov, A. Ya; Ivanov, K. A.; Tsymbalov, I. N.; Volkov, R. V.; Savel'ev, A. B.; Galanina, L. I.; Chirskaya, N. P.; Novikov, L. S.

    2017-06-01

    The possibilities of applying a femtosecond laser-plasma source of X-ray radiation for modelling the effect of single nuclear particles based on the principle of equivalent charge generation are analysed. The parameters of femtosecond X-ray radiation for the experimental modelling of individual radiation effects are validated. The experimental setup forming the X-ray radiation is described. The results of comparative ionisation response modelling in simple electronic devices using the FLUKA and FEANT codes are presented.

  18. Multidisciplinary approach to assess the sensitivity of dwarf tomato plants to low-LET ionising radiation

    NASA Astrophysics Data System (ADS)

    De Micco, Veronica; De Pascale, Stefania; Aronne, Giovanna; Paradiso, Roberta; Vitaglione, Paola; Turano, Mimmo; Arena, Carmen

    Ionising radiation, acting alone or in interaction with microgravity and other environmental constraints, may affect plant at molecular, morpho-structural and physiological level. The intensity of the plant’s response depends on the properties of radiation and on the features of the plant itself. Indeed, different species are characterised by different susceptibility to radiation which may change during the life course. The aim of this research was to study the radiosensitivity to low-LET ionising radiation of plants of dwarf tomato (Solanum lycopersicum L. ‘Microtom’) at two phenological phases (vegetative and reproductive), within the purpose of analysing plants for consideration as candidates for Bioregenerative Life Support Systems (BLSS) in Space. To pursue this objective, plants of the cultivar Microtom were irradiated with different doses of X-rays either at the stage of the second true leaf (VP - vegetative phase) or when at least one flower was blossomed (RP - reproductive phase). Plant’s response to ionising radiation was assessed through a multidisciplinary approach combining genetic analyses, ecophysiological measurements, morpho-anatomical characterisation of leaves and fruits, nutritional analyses of fruits. Growth, molecular and morpho-functional traits were measured during plant development up to fruiting in both VP and RP plant groups, and compared with non-irradiated control plants. Plant growth was monitored weekly recording parameters such as plant height, number of leaves, leaf area, flowering and fruiting rate. Potential DNA alterations were explored through Random Amplified Polymorphic DNA (RAPD) technique. The efficiency of the photosynthetic apparatus was evaluated by determining photosynthetic pigment composition, photochemistry and leaf gas exchanges. Leaf and fruit structure were analysed through light and epi-fluorescence microscopy. Leaf anatomical traits related to photosynthetic efficiency, and to structural radioprotection

  19. [Fatal home accidents in Tuscany in 2001-2002].

    PubMed

    Mantero, S; Lorini, C; Giovanetti, L; Chellini, E

    2007-01-01

    In the last years in Italy deaths due to accidents were more than 26.000/year. One of the most frequent places in which they occurred was at home, with more than 8.000 deaths/year. Due to the lack of studies related to this field, in Tuscany a specific study of fatal home accidents has been done. The cases studied, occurred in Tuscany in 2001-2002, have been extracted from the electronic database of the Regional Mortality Registry of Tuscany. Information about the modality of the accidents was collected by administering a questionnaire to the closest available relative of the victim. A total of 284 cases were studied, the majority of whom were female, over 75 years of age, with low educational level, pensioners, often with more than three pathologies. The accidents happened mostly in the bedroom or on the stairs due to accidental falls. The dynamics of fatal accidents showed great differences if compared to the nonfatal accidents. This suggests the need of different approaches for fatal injury surveillance and for the implementing of preventive strategies.

  20. Ionising radiation exposure in patients with circular frame treatment of distal tibial fractures.

    PubMed

    Bryant, H; Dearden, P M C; Harwood, P J; Wood, T J; Sharma, H K

    2015-08-01

    Total radiation exposure accumulated during circular frame treatment of distal tibial fractures was quantified in 47 patients treated by a single surgeon from February 2007 until Oct 2010. The radiation exposures for all relevant radiology procedures for the distal tibial injury were included to estimate the radiation risk to the patient. The median time of treatment in the frame was 169 days (range 105-368 days). Patients underwent a median of 13 sets of plain radiographs; at least one intra operative exposure and 16 patients underwent CT scanning. The median total effective dose per patient from time of injury to discharge was 0.025mSv (interquartile range 0.013-0.162 and minimum to maximum 0.01-0.53). The only variable shown to be an independent predictor of cumulative radiation dose on multivariate analysis was the use of CT scanning. This was associated with a 13-fold increase in overall exposure. Radiation exposure during treatment of distal tibial fractures with a circular frame in this group was well within accepted safe limits. The fact that use of CT was the only significant predictor of overall exposure serves as a reminder to individually assess the risk and utility of radiological investigations on an individual basis. This is consistent with the UK legal requirements for justification of all X-ray imaging, as set out in the Ionising Radiation (Medical Exposure) Regulations 2000 [1].

  1. Specification of the quality of ionising radiations for unified dosimetry in radiobiology and radiological protection

    NASA Astrophysics Data System (ADS)

    Alkharam, Ali Salem

    It is widely agreed in radiobiological and biophysical research that the DNA is the dominant target which can lead to terminal biological damage in the form of cancer or cell death. A main objective in radiation protection is to set the limits of the possible harmful effects to the general population exposed to ionising radiation at low level (environmental level). The initial slope of the dose-response curve is found to be an appropriate parameter to achieve this objective. Bench mark data sets of the initial effects of ionising radiation on cells in vitro were formed which include both physical characterisation of the radiation and the radiobiological parameters. These data-bases include the mammalian cell end-points: cellular inactivation, chromosome dicentrics, HPRT mutations and oncogenic transformations. On the molecular scale, the databases include single-strand and double strand breaks induced in the DNA of both mammalian and non-mammalian cells. Analysis of bio-effect mechanisms of damage to mammalian cells in terms of the quality parameter 'mean free path for linear primary ionisation' for ionising radiation, strongly suggest that there is a common mechanism for the biological endpoints of dicentrics, mutations, and oncogemc transformations. A unified response is obtained for all types of heavy ions and all cells which show: a common inflection point at inter-spacing distance equivalent to lambda0 = 1.4+/- 0.5 nm, a saturation region at lambda < lambda0 and almost constant slope for lambda < lambda0. The lethal lesions are identified as dsb's in the intracellular DNA. It follows that radiation risk factors can be determined on the basis of simple ratios to the inactivation cross sections. The size of these genes are found to be in close proximity to the optimised saturation levels. The probabilities of risk with respect to inactivation, for chromosome dicentrics, oncogenic transformations, and mutations of the HPRT gene are respectively 0.18, 1.6 x 10

  2. Correlation of spectroscopic and biochemical assays post-ionising radiation exposure in human skin cell analogues

    NASA Astrophysics Data System (ADS)

    Meade, A. D.; Byrne, H. J.; Lyng, F. M.

    2005-06-01

    Raman spectroscopy, as an evaluation of the products of ionising radiation exposure in biological systems, has been utilised mainly in the evaluation of the impact of exposure in tissue, cellular constituents and live animals. It has also been recently demonstrated that Raman spectroscopy can demonstrate key spectroscopic changes in the live cell associated with significant apoptotic and necrotic chemical damage. The present preliminary work utilises Raman spectroscopy at 514.5 nm to evaluate the results of exposure to γ-rays in HaCaT cells from a Co-60 therapy source, in tandem with other biological assays. The results demonstrate that Raman spectral changes may be correlated with changes in the cell also identified in parallel biochemical assays.

  3. Multicolour FISH analysis of ionising radiation induced micronucleus formation in human lymphocytes

    PubMed Central

    Balajee, Adayabalam S.; Bertucci, Antonella; Taveras, Maria; Brenner, David J.

    2014-01-01

    Micronucleation of chromosomal DNA is an effective indicator of DNA damage and micronucleus (MN) analysis is a valuable tool for radiation biodosimetry studies. To gain a comprehensive knowledge of micronucleation process after ionising radiation (IR) exposure, whole genome-wide chromosome analysis is desirable. With this objective, multicolour fluorescence in situ hybridization (M-FISH) technique was utilised in the present study to characterise the chromosome content of spontaneous and IR-induced micronuclei in three human donors. M-FISH analysis revealed a radiation dose-dependant increase in the number of micronuclei with multi-chromosome material above 2 Gy and as many as 3–6 multicolour signals were detected in micronuclei after high γ-rays radiation doses (5–10 Gy). Involvement of each human chromosome material was more frequently detected in multicoloured micronuclei than in single-coloured micronuclei at high radiation doses (>2 Gy). Observation of dose-dependant increase in the MN frequency with multi-chromosome material may be due to misrepair of DNA double-strand breaks involving multiple chromosomes leading to asymmetric dicentric or ring chromosomes and acentric fragments. Chromosomes belonging to groups A (1, 2 and 3) and B (4 and 5) were frequently detected in 35–45% of the total micronuclei either as single entities or in combination with other chromosomes. Among the A and B groups, chromosome 1 material was consistently detected at high MN frequencies after radiation exposure in all the donors. Additionally, chromosomes 13 and 19 were more frequently observed in micronuclei than the expected frequency based on DNA content. Our whole genome approach utilising the M-FISH technique revealed that MN formation at high radiation doses might be complex involving multiple chromosome fragments. Understanding the fate and biological consequences of these multi-chromosome-containing micronuclei may provide key molecular insights for some aspects of IR

  4. Age at exposure to ionising radiation and cancer mortality among Hanford workers: follow up through 1994

    PubMed Central

    Wing, S; Richardson, D

    2005-01-01

    Background: Studies of workers at the plutonium production factory in Hanford, WA have led to conflicting conclusions about the role of age at exposure as a modifier of associations between ionising radiation and cancer. Aims: To evaluate the influence of age at exposure on radiation risk estimates in an updated follow up of Hanford workers. Methods: A cohort of 26 389 workers hired between 1944 and 1978 was followed through 1994 to ascertain vital status and causes of death. External radiation dose estimates were derived from personal dosimeters. Poisson regression was used to estimate associations between mortality and cumulative external radiation dose at all ages, and in specific age ranges. Results: A total of 8153 deaths were identified, 2265 of which included cancer as an underlying or contributory cause. Estimates of the excess relative risk per Sievert (ERR/Sv) for cumulative radiation doses at all ages combined were negative for all cause and leukaemia and positive for all cancer and lung cancer. Cumulative doses accrued at ages below 35, 35–44, and 45–54 showed little association with mortality. For cumulative dose accrued at ages 55 and above (10 year lag), the estimated ERR/Sv for all cancers was 3.24 (90% CI: 0.80 to 6.17), primarily due to an association with lung cancer (ERR/Sv: 9.05, 90% CI: 2.96 to 17.92). Conclusions: Associations between radiation and cancer mortality in this cohort are primarily a function of doses at older ages and deaths from lung cancer. The association of older age radiation exposures and cancer mortality is similar to observations from several other occupational studies. PMID:15961623

  5. Occupational ionising radiation and risk of basal cell carcinoma in US radiologic technologists (1983-2005).

    PubMed

    Lee, Terrence; Sigurdson, Alice J; Preston, Dale L; Cahoon, Elizabeth K; Freedman, D Michal; Simon, Steven L; Nelson, Kenrad; Matanoski, Genevieve; Kitahara, Cari M; Liu, Jason J; Wang, Timothy; Alexander, Bruce H; Doody, Michele M; Linet, Martha S; Little, Mark P

    2015-12-01

    To determine risk for incident basal cell carcinoma from cumulative low-dose ionising radiation in the US radiologic technologist cohort. We analysed 65,719 Caucasian technologists who were cancer-free at baseline (1983-1989 or 1994-1998) and answered a follow-up questionnaire (2003-2005). Absorbed radiation dose to the skin in mGy for estimated cumulative occupational radiation exposure was reconstructed for each technologist based on badge dose measurements, questionnaire-derived work history and protection practices, and literature information. Radiation-associated risk was assessed using Poisson regression and included adjustment for several demographic, lifestyle, host and sun exposure factors. Cumulative mean absorbed skin dose (to head/neck/arms) was 55.8 mGy (range 0-1735 mGy). For lifetime cumulative dose, we did not observe an excess radiation-related risk (excess relative risk/Gy=-0.01 (95% CI -0.43 to 0.52). However, we observed that basal cell carcinoma risk was increased for radiation dose received before age 30 (excess relative risk/Gy=0.59, 95% CI -0.11 to 1.42) and before 1960 (excess relative risk/Gy=2.92, 95% CI 1.39 to 4.45). Basal cell carcinoma risk was unrelated to low-dose radiation exposure among radiologic technologists. Because of uncertainties in dosimetry and sensitivity to model specifications, both our null results and our findings of excess risk for dose received before age 30 and exposure before 1960 should be interpreted with caution. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  6. Low-dose ionising radiation and cardiovascular diseases--Strategies for molecular epidemiological studies in Europe.

    PubMed

    Kreuzer, Michaela; Auvinen, Anssi; Cardis, Elisabeth; Hall, Janet; Jourdain, Jean-Rene; Laurier, Dominique; Little, Mark P; Peters, Annette; Raj, Ken; Russell, Nicola S; Tapio, Soile; Zhang, Wei; Gomolka, Maria

    2015-01-01

    It is well established that high-dose ionising radiation causes cardiovascular diseases. In contrast, the evidence for a causal relationship between long-term risk of cardiovascular diseases after moderate doses (0.5-5 Gy) is suggestive and weak after low doses (<0.5 Gy). However, evidence is emerging that doses under 0.5 Gy may also increase long-term risk of cardiovascular disease. This would have major implications for radiation protection with respect to medical use of radiation for diagnostic purposes and occupational or environmental radiation exposure. Therefore, it is of great importance to gain information about the presence and possible magnitude of radiation-related cardiovascular disease risk at doses of less than 0.5 Gy. The biological mechanisms implicated in any such effects are unclear and results from epidemiological studies are inconsistent. Molecular epidemiological studies can improve the understanding of the pathogenesis and the risk estimation of radiation-induced circulatory disease at low doses. Within the European DoReMi (Low Dose Research towards Multidisciplinary Integration) project, strategies to conduct molecular epidemiological studies in this field have been developed and evaluated. Key potentially useful European cohorts are the Mayak workers, other nuclear workers, uranium miners, Chernobyl liquidators, the Techa river residents and several diagnostic or low-dose radiotherapy patient cohorts. Criteria for informative studies are given and biomarkers to be investigated suggested. A close collaboration between epidemiology, biology and dosimetry is recommended, not only among experts in the radiation field, but also those in cardiovascular diseases.

  7. Kootenai River Focus Watershed Coordination, 2001-2002 Annual Report.

    SciTech Connect

    Kruse, Gretchen

    2002-07-01

    The 2001-2002 Kootenai River Network Annual Report reflects the organization's defined set of goals and objectives, and how by accomplishing these goals, we continue to meet the needs of communities and landowners throughout the Kootenai River Basin by protecting the resource. Our completed and ongoing projects throughout the watershed reflect the cooperation and support received and needed to accomplish the rehabilitation and restoration of critical habitat. They show that our mission of facilitation through collaboration with public and private interests can lead to improved resource management, the restoration of water quality and the preservation of pristine aquatic resources. Our vision to empower local citizens and groups from two states, one province, two countries and affected tribal nations to collaborate in natural resource management within the basin is largely successful due to the engagement of the basin's residents--the landowners, town government, local interest groups, businesses and agency representatives who live and work here. We are proof that forging these types of cooperative relationships, such as those exhibited by the Kootenai River subbasin planning process, leads to a sense of entitlement--that the quality of the river and its resources enriches our quality of life. Communication is essential in maintaining these relationships. Allowing ourselves to network and receive ideas and information, as well as to produce quality, accessible research data such as KRIS, shared with like organizations and individuals, is the hallmark of this facilitative organization. We are fortunate in the ability to contribute such information, and continue to strive to meet the standards and the needs of those who seek us out as a model for watershed rehabilitative planning and restoration. Sharing includes maintaining active, ongoing lines of communication with the public we serve--through our web site, quarterly newsletter, public presentations and stream

  8. 7 CFR 929.251 - Marketable quantity and allotment percentage for the 2001-2002 crop year.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 2001-2002 crop year. 929.251 Section 929.251 Agriculture Regulations of the Department of Agriculture... § 929.251 Marketable quantity and allotment percentage for the 2001-2002 crop year. The marketable quantity for the 2001-2002 crop year is set at 4.6 million barrels and the allotment percentage...

  9. 7 CFR 929.251 - Marketable quantity and allotment percentage for the 2001-2002 crop year.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 2001-2002 crop year. 929.251 Section 929.251 Agriculture Regulations of the Department of Agriculture... § 929.251 Marketable quantity and allotment percentage for the 2001-2002 crop year. The marketable quantity for the 2001-2002 crop year is set at 4.6 million barrels and the allotment percentage...

  10. 7 CFR 929.251 - Marketable quantity and allotment percentage for the 2001-2002 crop year.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 2001-2002 crop year. 929.251 Section 929.251 Agriculture Regulations of the Department of Agriculture... § 929.251 Marketable quantity and allotment percentage for the 2001-2002 crop year. The marketable quantity for the 2001-2002 crop year is set at 4.6 million barrels and the allotment percentage is...

  11. 71 FR 64761 - Denial of Petitions for Import Eligibility for Nonconforming 2001-2002 Mitsubishi Evolution VII...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2006-11-03

    ... 2001-2002 Mitsubishi Evolution VII and 2003 Mitsubishi Evolution VIII Left Hand Drive Passenger Cars... Eligibility for nonconforming 2001-2002 Mitsubishi Evolution VII and 2003 Mitsubishi Evolution VIII left hand... left-hand drive (LHD) 2001-2002 Mitsubishi Evolution VII and 2003 Mitsubishi Evolution VIII LHD...

  12. Efficiency of generation of highly ionised atoms under resonance absorption of CO{sub 2}-laser radiation

    SciTech Connect

    Gus'kov, Sergei Yu; Demchenko, N N; Makarov, K N; Rozanov, Vladislav B; Satov, Yu A; Sharkov, Boris Yu

    2011-10-31

    We consider the generation of beams of highly ionised atoms in solid targets irradiated with CO{sub 2}-laser pulses. We present experimental results on generation of Mg and Pb ions from laser plasma at a radiation flux density q Almost-Equal-To 10{sup 14} W cm{sup -2}. We have developed a theoretical model describing the plasma heating by CO{sub 2}-laser radiation at a high pulse intensity on the target, taking into account the ponderomotive forces affecting the behaviour of the interaction of light with the plasma. It is shown that in the case of resonance absorption of laser radiation by the plasma, the efficiency of generation of highly ionised atoms of the target substance is higher than the efficiency of generation in the case of classical absorption. The results of the numerical calculation by the developed model are in good agreement with the experiment.

  13. ASSOCIATION OF URINARY PERCHLORATE WITH INDIRECT MEASURES OFTHYROID DYSFUNCTION BASED ON NHANES 2001-2002

    EPA Science Inventory

    Background/Aims: Perchlorate is a widespread environmental pollutant. Previous population studies based on the National Health and Nutrition Examination Survey (NHANES) 2001-2002, showed that urinary perchlorate concentrations were associated with increased levels of thyroid stim...

  14. ASSOCIATION OF URINARY PERCHLORATE WITH INDIRECT MEASURES OFTHYROID DYSFUNCTION BASED ON NHANES 2001-2002

    EPA Science Inventory

    Background/Aims: Perchlorate is a widespread environmental pollutant. Previous population studies based on the National Health and Nutrition Examination Survey (NHANES) 2001-2002, showed that urinary perchlorate concentrations were associated with increased levels of thyroid stim...

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

    NASA Astrophysics Data System (ADS)

    Daar, Eman; Woods, E.; Keddie, J. L.; Nisbet, A.; Bradley, D. A.

    2010-07-01

    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.

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

    PubMed

    Karapiperis, Christos; Kempf, Stefan J; Quintens, Roel; Azimzadeh, Omid; Vidal, Victoria Linares; Pazzaglia, Simonetta; Bazyka, Dimitry; Mastroberardino, Pier G; Scouras, Zacharias G; Tapio, Soile; Benotmane, Mohammed Abderrafi; Ouzounis, Christos A

    2016-05-11

    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 explored using omics technologies. We describe a light-weight approach for the storage, analysis and distribution of relevant LDIR omics datasets. The data integration platform, called BRIDE, contains information from the literature as well as experimental information from transcriptomics and proteomics studies. It deploys a hybrid, distributed solution using both local storage and cloud technology. BRIDE can act as a knowledge broker for LDIR researchers, to facilitate molecular research on the systems biology of LDIR response in mammals. Its flexible design can capture a range of experimental information for genomics, epigenomics, transcriptomics, and proteomics. The data collection is available at: .

  17. Multicolour FISH analysis of ionising radiation induced micronucleus formation in human lymphocytes.

    PubMed

    Balajee, Adayabalam S; Bertucci, Antonella; Taveras, Maria; Brenner, David J

    2014-11-01

    Micronucleation of chromosomal DNA is an effective indicator of DNA damage and micronucleus (MN) analysis is a valuable tool for radiation biodosimetry studies. To gain a comprehensive knowledge of micronucleation process after ionising radiation (IR) exposure, whole genome-wide chromosome analysis is desirable. With this objective, multicolour fluorescence in situ hybridization (M-FISH) technique was utilised in the present study to characterise the chromosome content of spontaneous and IR-induced micronuclei in three human donors. M-FISH analysis revealed a radiation dose-dependant increase in the number of micronuclei with multi-chromosome material above 2 Gy and as many as 3-6 multicolour signals were detected in micronuclei after high γ-rays radiation doses (5-10 Gy). Involvement of each human chromosome material was more frequently detected in multicoloured micronuclei than in single-coloured micronuclei at high radiation doses (>2 Gy). Observation of dose-dependant increase in the MN frequency with multi-chromosome material may be due to misrepair of DNA double-strand breaks involving multiple chromosomes leading to asymmetric dicentric or ring chromosomes and acentric fragments. Chromosomes belonging to groups A (1, 2 and 3) and B (4 and 5) were frequently detected in 35-45% of the total micronuclei either as single entities or in combination with other chromosomes. Among the A and B groups, chromosome 1 material was consistently detected at high MN frequencies after radiation exposure in all the donors. Additionally, chromosomes 13 and 19 were more frequently observed in micronuclei than the expected frequency based on DNA content. Our whole genome approach utilising the M-FISH technique revealed that MN formation at high radiation doses might be complex involving multiple chromosome fragments. Understanding the fate and biological consequences of these multi-chromosome-containing micronuclei may provide key molecular insights for some aspects of IR

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

    PubMed Central

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

    2016-01-01

    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

  19. On the divergences in assessment of environmental impacts from ionising radiation following the Fukushima accident.

    PubMed

    Strand, P; Sundell-Bergman, S; Brown, J E; Dowdall, M

    2017-04-01

    The accident at the Fukushima-Daiichi Nuclear Power Station on March 11, 2011, led to significant contamination of the surrounding terrestrial and marine environments. Whilst impacts on human health remain the primary concern in the aftermath of such an accident, recent years have seen a significant body of work conducted on the assessment of the accident's impacts on both the terrestrial and marine environment. Such assessments have been undertaken at various levels of biological organisation, for different species, using different methodologies and coming, in many cases, to divergent conclusions as to the effects of the accident on the environment. This article provides an overview of the work conducted in relation to the environmental impacts of the Fukushima accident, critically comparing and contrasting methodologies and results with a view towards finding reasons for discrepancies, should they indeed exist. Based on the outcomes of studies conducted to date, it would appear that in order to avoid the fractured and disparate conclusions drawn in the aftermath of previous accidents, radioactive contaminants and their effects can no longer simply be viewed in isolation with respect to the ecosystems these effects may impact. A combination of laboratory based and field studies with a focus on ecosystem functioning and effects could offer the best opportunities for coherence in the interpretation of the results of studies into the environmental impacts of ionising radiation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Urinary iodine concentration: United States National Health And Nutrition Examination Survey 2001-2002.

    PubMed

    Caldwell, Kathleen L; Jones, Robert; Hollowell, Joseph G

    2005-07-01

    Urine iodine has been measured in the U.S. population by the National Health and Nutrition Examination Survey (NHANES) since 1971. A downward trend was noted between NHANES I (320 +/- 6 microg/L in 1971-1974) and NHANES III (145 +/- 3 microg/L in 1988-1994). This report presents data from NHANES 2001-2002 that indicates that the U.S. median urine iodine (UI) level has stabilized since the initial drop between NHANES I and NHANES III. The median UI concentration in the U.S. population in NHANES 2001-2002 was found to be 167.8 microg/L (95% confidence interval [CI] 159.3-177.6). The NHANES 2001-2002 data confirm the current stability of the U.S. iodine intake and continued adequate iodine nutrition for the country.

  1. Resveratrol and its methoxy-derivatives as modulators of DNA damage induced by ionising radiation.

    PubMed

    Traversi, Gianandrea; Fiore, Mario; Leone, Stefano; Basso, Emiliano; Di Muzio, Elena; Polticelli, Fabio; Degrassi, Francesca; Cozzi, Renata

    2016-07-01

    Various naturally occurring stilbene-like compounds that are related to resveratrol (RSV) possess some of the beneficial effects of the parent molecule and provide even further benefits. Therefore, a series of methoxylated analogues of RSV were prepared with the aim of increasing antitumour and proapoptotic activity. In a previous article, we studied two methoxy-derivatives, pterostilbene (PTERO) and trimethoxystilbene (TRIMETHOXY), in which the first was formed by the substitution of two hydroxyl groups with two methoxy groups (trans-3,5-dimethoxy-4'-hydroxystilbene) and the second was formed by the replacement of all three OH groups with methoxy groups (trans-3,5,4'-trimethoxystilbene). Both methoxy-derivatives showed stronger antioxidant activity when compared with RSV. In the present article, we focused on the analysis of the ability of RSV and its two methoxylated derivatives to protect proliferating non-tumoural cells from the damage induced by ionising radiation (IR). First we showed that the methoxy derivatives, contrary to their parental compound, are unable to affect topoisomerase enzyme and consequently are not clastogenic per se Second we showed that both PTERO and TRIMETHOXY more efficiently reduce the chromosome damage induced by IR. Furthermore, TRIMETHOXY, but not PTERO, causes a delay in cell proliferation, particularly in mitosis progression increasing the number of cells in metaphase at the expense of prophases and ana/telophases. © The Author 2016. Published by Oxford University Press on behalf of the UK Environmental Mutagen Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  2. Radiation in the workplace-a review of studies of the risks of occupational exposure to ionising radiation.

    PubMed

    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

  3. Leaf Anatomy and Photochemical Behaviour of Solanum lycopersicum L. Plants from Seeds Irradiated with Low-LET Ionising Radiation

    PubMed Central

    De Micco, V.; Paradiso, R.; Aronne, G.; De Pascale, S.; Quarto, M.; Arena, C.

    2014-01-01

    Plants can be exposed to ionising radiation not only in Space but also on Earth, due to specific technological applications or after nuclear disasters. The response of plants to ionising radiation depends on radiation quality/quantity and/or plant characteristics. In this paper, we analyse some growth traits, leaf anatomy, and ecophysiological features of plants of Solanum lycopersicum L. “Microtom” grown from seeds irradiated with increasing doses of X-rays (0.3, 10, 20, 50, and 100 Gy). Both juvenile and compound leaves from plants developed from irradiated and control seeds were analysed through light and epifluorescence microscopy. Digital image analysis allowed quantifying anatomical parameters to detect the occurrence of signs of structural damage. Fluorescence parameters and total photosynthetic pigment content were analysed to evaluate the functioning of the photosynthetic machinery. Radiation did not affect percentage and rate of seed germination. Plants from irradiated seeds accomplished the crop cycle and showed a more compact habitus. Dose-depended tendencies of variations occurred in phenolic content, while other leaf anatomical parameters did not show distinct trends after irradiation. The sporadic perturbations of leaf structure, observed during the vegetative phase, after high levels of radiation were not so severe as to induce any significant alterations in photosynthetic efficiency. PMID:24883400

  4. INTERACTION OF LASER RADIATION WITH MATTER. LASER PLASMA: Evolution of tubular singular pulsed beams in a nonlinear dielectric medium upon ionisation

    NASA Astrophysics Data System (ADS)

    Vlasov, R. A.; Khasanov, O. Kh; Smirnova, T. V.

    2005-10-01

    The dynamics of a high-power femtosecond tubular pulsed beam in a dielectric medium is numerically analysed upon optically induced ionisation. It is found that the balance between nonlinearities of opposite sign and different magnitude in the case of multiphoton ionisation favours the establishment of a quasi-soliton regime of radiation propagation over a distance exceeding several diffraction lengths. The use of these beams enables attaining high-density light fields and generate high-density plasmas.

  5. Nurses', physicians' and radiographers' perceptions of the safety of a nurse prescribing of ionising radiation initiative: A cross-sectional survey.

    PubMed

    Hyde, Abbey; Coughlan, Barbara; Naughton, Corina; Hegarty, Josephine; Savage, Eileen; Grehan, Jennifer; Kavanagh, Eoin; Moughty, Adrian; Drennan, Jonathan

    2016-06-01

    A new initiative was introduced in Ireland following legislative changes that allowed nurses with special training to prescribe ionising radiation (X-ray) for the first time. A small number of studies on nurse prescribing of ionising radiation in other contexts have found it to be broadly as safe as ionising radiation prescribing by physicians. Sociological literature on perceptions of safety indicates that these tend to be shaped by the ideological position of the professional rather than based on objective evidence. To describe, compare and analyse perceptions of the safety of a nurse prescribing of ionising radiation initiative across three occupational groups: nursing, radiography and medicine. A cross-sectional survey design. Participants were drawn from a range of clinical settings in Ireland. Respondents were 167 health professionals comprised of 49 nurses, 91 radiographers, and 27 physicians out of a total of 300 who were invited to participate. Non-probability sampling was employed and the survey was targeted specifically at health professionals with a specific interest in, or involvement with, the development of the nurse prescribing of ionising radiation initiative in Ireland. Comparisons of perspectives on the safety of nurse prescribing of ionising radiation across the three occupational groups captured by questionnaire were analysed using the Kruskal-Wallis H test. Pairwise post hoc tests were conducted using the Mann-Whitney U test. While the majority of respondents from all three groups perceived nurse prescribing of ionising radiation to be safe, the extent to which this view was held varied. A higher proportion of nurses was found to display confidence in the safety of nurse prescribing of ionising radiation compared to physicians and radiographers with differences between nurses' perceptions and those of the other two groups being statistically significant. That an occupational patterning emerged suggests that perceptions about safety and risk of

  6. HEALTH EFFECTS ASSOCIATED WITH SUBLETHAL EXPOSURE TO MICROCYSTINS AMONG DIALYSIS PATIENTS, BRAZIL, 2001-2002

    EPA Science Inventory

    Background: During winter 2001-2002, an episode of microcystin exposure occurred among dialysis patients in Rio de Janiero, Brazil. During late November 2001, a cyanobacterial water bloom was detected in the Funil reservoir and the Guandu River, both of which supply drinking wate...

  7. Institutional Accountability Plan and Progress Report. 2002 Update, Year 9, 2001-2002.

    ERIC Educational Resources Information Center

    Pensacola Junior Coll., FL. Office of Institutional Research and Effectiveness.

    This document addresses the state approved accountability measure plans for Pensacola Junior College in the academic year 2001-2002. This edition is the ninth annual report on PJC's performance in compliance with Florida Statutes. The document is divided into 24 measures including the following: (1) enrollments, retention and success rates for AA…

  8. Parkland College Student Occupational Follow-Up Survey, 2001-2002.

    ERIC Educational Resources Information Center

    Parkland Coll., Champaign, IL. Office of Institutional Research and Evaluation.

    This study presents the findings of the 2001-2002 Student Occupational Follow-Up Survey of graduates of Parkland College, Illinois. A total of 595 graduates of occupational programs were contacted approximately five weeks after graduation. Of those, 352 returned surveys, for a response rate of 59.2%. Females outnumbered males by more than two to…

  9. Parkland College Transfer Program Graduate Follow-Up Survey, 2001-2002.

    ERIC Educational Resources Information Center

    Parkland Coll., Champaign, IL. Office of Institutional Research and Evaluation.

    This study presents findings from the 2001-2002 Transfer Program Follow-Up Survey of Parkland College (Illinois) graduates. A total of 423 students from baccalaureate/transfer programs were contacted approximately 6 weeks after graduation. Of those, 253 returned surveys, for a response rate of 59.8%. More than 58% of respondents were female, 81%…

  10. Institutional Effectiveness through Plan & Budget Integration. Strategic Plan Guide, 2001-2002.

    ERIC Educational Resources Information Center

    Wayne Community Coll., Goldsboro, NC.

    This document describes Wayne Community College's (North Carolina) strategic plan for 2001-2002. The college's goals, as well as objectives set forth by the North Carolina Community College System, are discussed. Long-range goals include: (1) enhancing student success through college-wide programs and services; (2) providing opportunities for…

  11. Responding to a Strong Economy. Alberta Apprenticeship and Industry Training Board 2001-2002 Annual Report.

    ERIC Educational Resources Information Center

    Alberta Learning, Edmonton. Apprenticeship and Industry Training.

    In 2001-2002, the Alberta Apprenticeship and Industry Training Board continued its collaboration with industry, government, and educators to maintain high standards of training and improve access to technical training. The board continued to strengthen the network of local and provincial apprenticeship committees, occupational committees, and…

  12. The "Isms" of Art. Introduction to the 2001-2002 Clip and Save Art Prints.

    ERIC Educational Resources Information Center

    Hubbard, Guy

    2001-01-01

    Provides an introduction to the 2001-2002 Clip and Save Art Prints that will focus on ten art movements from the past 150 years. Includes information on three art movements, or "isms": Classicism, Romanticism, and Realism. Discusses the Clip and Save Art Print format and provides information on three artists. (CMK)

  13. The "Isms" of Art. Introduction to the 2001-2002 Clip and Save Art Prints.

    ERIC Educational Resources Information Center

    Hubbard, Guy

    2001-01-01

    Provides an introduction to the 2001-2002 Clip and Save Art Prints that will focus on ten art movements from the past 150 years. Includes information on three art movements, or "isms": Classicism, Romanticism, and Realism. Discusses the Clip and Save Art Print format and provides information on three artists. (CMK)

  14. Child Care Assistance: Helping Families Work. Annual Report, 2001-2002.

    ERIC Educational Resources Information Center

    Greater Minneapolis Day Care Association, MN.

    This annual report of the Greater Minneapolis Day Care Association (GMDCA) details the accomplishments of the organization for 2001-2002. The report begins with a letter from the executive director focusing on need to continue funding for the Basic Sliding Fee Child-Care Assistance program to help low- and moderate-income working families. The…

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

    PubMed

    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.

  16. Static electric fields interfere in the viability of cells exposed to ionising radiation.

    PubMed

    Arruda-Neto, João D T; Friedberg, Errol C; Bittencourt-Oliveira, Maria C; Cavalcante-Silva, Erika; Schenberg, Ana C G; Rodrigues, Tulio E; Garcia, Fermin; Louvison, Monica; Paula, Claudete R; Mesa, Joel; Moron, Michelle M; Maria, Durvanei A; Genofre, Godofredo C

    2009-04-01

    The interference of electric fields (EF) with biological processes is an issue of considerable interest. No studies have as yet been reported on the combined effect of EF plus ionising radiation. Here we report studies on this combined effect using the prokaryote Microcystis panniformis, the eukaryote Candida albicans and human cells. Cultures of Microcystis panniformis (Cyanobacteria) in glass tubes were irradiated with doses in the interval 0.5-5 kGy, using a (60)Co gamma source facility. Samples irradiated with 3 kGy were exposed for 2 h to a 20 V . cm(-1) static electric field and viable cells were enumerated. Cultures of Candida albicans were incubated at 36 degrees C for 20 h, gamma-irradiated with doses from 1-4 kGy, and submitted to an electric field of 180 V . cm(-1). Samples were examined under a fluorescence microscope and the number of unviable (red) and viable (apple green fluorescence) cells was determined. For crossing-check purposes, MRC5 strain of lung cells were irradiated with 2 Gy, exposed to an electric field of 1250 V/cm, incubated overnight with the anti-body anti-phospho-histone H2AX and examined under a fluorescence microscope to quantify nuclei with gamma-H2AX foci. In cells exposed to EF, death increased substantially compared to irradiation alone. In C. albicans we observed suppression of the DNA repair shoulder. The effect of EF in growth of M. panniformis was substantial; the number of surviving cells on day-2 after irradiation was 12 times greater than when an EF was applied. By the action of a static electric field on the irradiated MRC5 cells the number of nuclei with gamma-H2AX foci increased 40%, approximately. Application of an EF following irradiation greatly increases cell death. The observation that the DNA repair shoulder in the survival curve of C. albicans is suppressed when cells are exposed to irradiation + EF suggests that EF likely inactivate cellular recovering processes. The result for the number of nuclei with gamma

  17. Induction of Hsp70 by desiccation, ionising radiation and heat-shock in the eutardigrade Richtersius coronifer.

    PubMed

    Jönsson, K Ingemar; Schill, Ralph O

    2007-04-01

    The physiology and biochemistry behind the extreme tolerance to desiccation shown by the so-called anhydrobiotic animals represents an exciting challenge to biology. The current knowledge suggests that both carbohydrates and proteins are often involved in protecting the dry cell from damage, or in the repair of induced damage. Tardigrades belong to the most desiccation-tolerant multicellular organisms, but very little research has been reported on the biochemistry behind desiccation tolerance in this group. We quantified the induction of the heat-shock protein Hsp70, a very wide-spread stress protein, in response to desiccation, ionising radiation, and heating, in the anhydrobiotic tardigrade Richtersius coronifer using an immuno-westernblot method. Elevated levels of Hsp70 were recorded after treatment of both heat and ionising radiation, and also in rehydrated tardigrades after a period of desiccation. In contrast, tardigrades in the desiccated (dry) state had reduced Hsp70 levels compared to the non-treated control group. Our results suggest that Hsp70 may be involved in the physiological and biochemical system underlying desiccation (and radiation) tolerance in tardigrades, and that its role may be connected to repair processes after desiccation rather than to biochemical stabilization in the dry state.

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

    PubMed

    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. © The International Society for Prosthetics and Orthotics.

  19. Microsatellite analysis for determination of the mutagenicity of extremely low-frequency electromagnetic fields and ionising radiation in vitro.

    PubMed

    Mairs, Robert J; Hughes, Kate; Fitzsimmons, Sara; Prise, Kevin M; Livingstone, Anne; Wilson, Lesley; Baig, Nazia; Clark, Anne Marie; Timpson, Alan; Patel, Gaurang; Folkard, M; Angerson, Wilson J; Boyd, Marie

    2007-01-10

    Extremely low-frequency electromagnetic fields (ELF-EMF) have been reported to induce lesions in DNA and to enhance the mutagenicity of ionising radiation. However, the significance of these findings is uncertain because the determination of the carcinogenic potential of EMFs has largely been based on investigations of large chromosomal aberrations. Using a more sensitive method of detecting DNA damage involving microsatellite sequences, we observed that exposure of UVW human glioma cells to ELF-EMF alone at a field strength of 1 mT (50 Hz) for 12 h gave rise to 0.011 mutations/locus/cell. This was equivalent to a 3.75-fold increase in mutation induction compared with unexposed controls. Furthermore, ELF-EMF increased the mutagenic capacity of 0.3 and 3 Gy gamma-irradiation by factors of 2.6 and 2.75, respectively. These results suggest not only that ELF-EMF is mutagenic as a single agent but also that it can potentiate the mutagenicity of ionising radiation. Treatment with 0.3 Gy induced more than 10 times more mutations per unit dose than irradiation with 3 Gy, indicating hypermutability at low dose.

  20. The DISAM Journal of International Security Assistance Management. Volume 24, Number 2, Winter 2001-2002

    DTIC Science & Technology

    2002-01-01

    Lieutenant General Tome H . Walters Jr., Director of the Defense Security Cooperation Agency, outlines the use of Performance Based Costing and Budgeting to...by ensuring the information is both appropriate and timely! RONALD H . REYNOLDS Commandant The DISAM Journal, Winter 2001-2002i Report Documentation...52 Lieutenant General Tome H . Walters, Jr., USAF, Defense Security Cooperation Agency “Performance Based Budgeting and

  1. [Childhood immunization schedule 2001-2002. Advisory Committee on Vaccines of the Spanish Association of Pediatrics].

    PubMed

    2001-07-01

    In 1994 the Spanish Association of Pediatrics founded the Advisory Committee on Vaccines with the aim of providing advice on matters related to childhood immunizations and of implementing vaccination schedules. The latest recommendations concern the immunization schedule for 2001-2002, in which indications for the inactivated poliovirus vaccine instead of the attenuated poliovirus vaccine are of prime importance. The advisability of including the vaccine against chicken pox in healthy children is stressed.

  2. Chronic low-dose-rate ionising radiation affects the hippocampal phosphoproteome in the ApoE−/− Alzheimer's mouse model

    PubMed Central

    Kempf, Stefan J.; Janik, Dirk; Barjaktarovic, Zarko; Braga-Tanaka, Ignacia; Tanaka, Satoshi; Neff, Frauke; Saran, Anna; Larsen, Martin R.; Tapio, Soile

    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 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 of synaptic plasticity, calcium-dependent signalling and brain metabolism. An inhibition of CREB signalling was found at both dose rates whereas Rac1-Cofilin signalling was found activated only at the lower dose rate. Similarly, the reduction in the number of activated microglia in the molecular layer of hippocampus that paralleled with reduced levels of TNFα expression and lipid peroxidation was significant only at the lower dose rate. Adult neurogenesis, investigated by Ki67, GFAP and NeuN staining, and cell death (activated caspase-3) were not influenced at any dose or dose rate. This study shows 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. PMID:27708245

  3. Lemna minor plants chronically exposed to ionising radiation: RNA-seq analysis indicates a dose rate dependent shift from acclimation to survival strategies.

    PubMed

    Van Hoeck, Arne; Horemans, Nele; Nauts, Robin; Van Hees, May; Vandenhove, Hildegarde; Blust, Ronny

    2017-04-01

    Ecotoxicological research provides knowledge on ionising radiation-induced responses in different plant species. However, the sparse data currently available are mainly extracted from acute exposure treatments. To provide a better understanding of environmental exposure scenarios, the response to stress in plants must be followed in more natural relevant chronic conditions. We previously showed morphological and biochemical responses in Lemna minor plants continuously exposed for 7days in a dose-rate dependent manner. In this study responses on molecular (gene expression) and physiological (photosynthetic) level are evaluated in L. minor plants exposed to ionising radiation. To enable this, we examined the gene expression profiles of irradiated L. minor plants by using an RNA-seq approach. The gene expression data reveal indications that L. minor plants exposed at lower dose rates, can tolerate the exposure by triggering acclimation responses. In contrast, at the highest dose rate tested, a high number of genes related to antioxidative defense systems, DNA repair and cell cycle were differentially expressed suggesting that only high dose rates of ionising radiation drive L. minor plants into survival strategies. Notably, the photosynthetic process seems to be unaffected in L. minor plants among the tested dose rates. This study, supported by our earlier work, clearly indicates that plants shift from acclimation responses towards survival responses at increasing dose rates of ionising radiation. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Thermoluminescent properties of Ni and Co doped synthetic, high pressure, high temperature diamonds: application to ionising radiation dosimetry.

    PubMed

    Benabdesselam, M; Iacconi, P; Gheeraert, E; Kanda, H; Lapraz, D; Briand, D

    2002-01-01

    An investigation of the thermoluminescence (TL) properties of high pressure, high temperature (HPHT) synthetic diamond crystals grown under diluted nickel or cobalt as solvent catalysts is reported. After a study of TL properties of 6 different samples, it is shown that a crystal grown with Ni+2%Ti and annealed at 2100 K presents an intense glow peak at around 490 K. This peak is characterised by a broad emission band centred at 530 nm (2.34 eV). This crystal presents a significant, reproducible and linear TL response relative to the absorbed dose up to an X ray air kerma of 10 Gy. All these features make this material suitable for ionising radiation dosimetry. A similar study is made on another crystal grown from pure Co, and a comparative review of the results does show that for dosimetry work, Ni-containing diamonds are more appropriate than those grown from Co catalyst.

  5. 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.

    PubMed

    Geisel, Dominik; Zimmermann, Elke; Rief, Matthias; Greupner, Johannes; Laule, Michael; Knebel, Fabian; Hamm, Bernd; Dewey, Marc

    2012-08-01

    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. • Radiation dose causes concern for both conventional coronary angiography and cardiac CT. • Estimations of the biological effects of ionising radiation may become feasible. • Fewer DNA double-strand breaks are induced by cardiac CT than CCA. • Conversion factors may underestimate the relative effects of ionising radiation from CCA.

  6. Effect of ionising radiation treatment on the specific migration characteristics of packaging-food simulant combinations: effect of type and dose of radiation.

    PubMed

    Zygoura, P D; Paleologos, E K; Kontominas, M G

    2011-05-01

    Migration levels of acetyl tributyl citrate (ATBC) plasticiser from polyvinyl chloride (PVC) film into the European Union specified aqueous food simulants (distilled water, 3% w/v acetic acid and 10% v/v ethanol) were monitored as a function of time. Migration testing was carried out at 40°C for 10 days. Determination of the analyte was performed by applying an analytical methodology based on surfactant (Triton X-114) mediated extraction prior to gas chromatographic-flame ionisation detection. PVC cling film used was subjected to ionising treatment with a [(60)Co] source, as well as to electron-beam irradiation at doses equal to 5, 15 and 25 kGy, with the aim to compare the effect of type and dose of radiation on the specific migration behaviour of PVC. Equilibrium concentrations of acetyl tributyl citrate into the aqueous solvents covered the ranges 173-422 µg l(-1) and 296-513 µg l(-1) for gamma- and electron-irradiated PVC, respectively. Hence, e-beam irradiation resulted in significantly higher ATBC migration compared with gamma treatment. The highest extraction efficiency of the 10% ethanol solution was common in both gamma and e-beam treatments; distilled water demonstrated the lowest migration. Gamma-irradiation at intermediate doses up to 5 kGy produced no statistically significant (p > 0.05) effect on ATBC migration into all three aqueous simulants; however, this does not apply for high-energy electrons. Both ionising treatments were similar in that they resulted in statistically significant (p < 0.05) differences in plasticiser migrating amounts between non-irradiated and irradiated at doses of 15 and 25 kGy samples. Gamma-radiation did not affect the kinetics of plasticiser migration. On the contrary, electron-beam radiation produced shorter equilibration times for all food-simulating solvents tested at 40°C. The above values regarding ATBC migration into aqueous food simulants are far below the European Union restriction (1 mg kg(-1) body weight

  7. Evaluating the Effectiveness of the 2001-2002 NASA "Why?" Files Program

    NASA Technical Reports Server (NTRS)

    Pinelli, Thomas E.; Frank, Kari Lou; Lambert, Matthew A.

    2002-01-01

    This report contains the results of the evaluation conducted for the 2001-2002 NASA 'Why?' Files program that was conducted in March 2002. The analysis is based on the results of 139 surveys collected from educators registered for the program. Respondents indicated that (1) the programs in the series are aligned with the national mathematics, science, and technology standards; (2) the programs are developmentally (grade level) appropriate; and (3) the programs enhance and enrich the teaching and learning of mathematics, science, and technology.

  8. Evaluating the Effectiveness of the 2001-2002 NASA CONNECT(tm) Program

    NASA Technical Reports Server (NTRS)

    Pinelli, Thomas E.; Frank, Kari Lou; Lambert, Matthew A.; Williams, Amy C.

    2002-01-01

    NASA CONNECT(tm) is a research and standards-based, integrated mathematics, science, and technology series of 30-minute instructional distance learning (television and web-based) programs for students in grades 6-8. Respondents who evaluated the programs in the 2001-2002 NASA CONNECT(tm) series reported that (1) they used the programs in the series; (2) the goals and objectives for the series were met; (3) the programs were aligned with the national mathematics, science, and technology standards; (4) the program content was developmentally appropriate for grade level; and (5) the programs in the series enhanced and enriched the teaching of mathematics, science, and technology.

  9. Teenage conceptions by small area deprivation in England and Wales, 2001-2002.

    PubMed

    Uren, Zoe; Sheers, Dilwyn; Dattani, Nirupa

    2007-01-01

    This article examines the relationship between teenage conceptions and deprivation in England and Wales in 2001-2002 using data at census ward level. Teenage conceptions are defined as births and abortions to women conceiving under the age of 18. Deprivation has been measured using Carstairs scores rebased using the 2001 Census. For the first time at ward level, analysis has differentiated between births and abortions resulting from teenage conceptions. Findings confirm the strong association between teenage conceptions and deprivation and also that deprivation has a strong influence on the likelihood of conceptions leading to either birth or abortion, although regional variations were observed for this relationship.

  10. [Low dose ionising radiation and cancer: findings and methods. Report of a meeting and consequences for Switzerland].

    PubMed

    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

  11. Considerations concerning the use of counting active personal dosimeters in pulsed fields of ionising radiation.

    PubMed

    Ambrosi, Peter; Borowski, Markus; Iwatschenko, Michael

    2010-06-01

    Active personal electronic dosimeters (APDs) exhibit limitations in pulsed radiation fields, which cannot be overcome without the use of new detection technology. As an interim solution, this paper proposes a method by which some conventional dosimeters can be operated in a way such that, based on the basic knowledge about the pulsed radiation field, any dosimetric failure of the dosimeter is signalised by the instrument itself. This method is not applicable to all combinations of APD and pulsed radiation field. The necessary requirements for the APD and for the parameters of the pulsed radiation field are given in the paper. Up to now, all such requirements for APDs have not been tested or verified in a type test. The suitability of the method is verified for the use of one APD used in two clinical pulsed fields.

  12. Implications for human and environmental health of low doses of ionising radiation.

    PubMed

    Mothersill, Carmel; Seymour, Colin

    2014-07-01

    The last 20 years have seen a major paradigm shift in radiation biology. Several discoveries challenge the DNA centric view which holds that DNA damage is the critical effect of radiation irrespective of dose. This theory leads to the assumption that dose and effect are simply linked - the more energy deposition, the more DNA damage and the greater the biological effect. This is embodied in radiation protection (RP) regulations as the linear-non-threshold (LNT) model. However the science underlying the LNT model is being challenged particularly in relation to the environment because it is now clear that at low doses of concern in RP, cells, tissues and organisms respond to radiation by inducing responses which are not readily predictable by dose. These include adaptive responses, bystander effects, genomic instability and low dose hypersensitivity, and are commonly described as stress responses, while recognizing that "stress" can be good as well as bad. The phenomena contribute to observed radiation responses and appear to be influenced by genetic, epigenetic and environmental factors, meaning that dose and response are not simply related. The question is whether our discovery of these phenomena means that we need to re-evaluate RP approaches. The so-called "non-targeted" mechanisms mean that low dose radiobiology is very complex and supra linear or sub-linear (even hormetic) responses are possible but their occurrence is unpredictable for any given system level. Issues which may need consideration are synergistic or antagonistic effects of other pollutants. RP, at present, only looks at radiation dose but the new (NTE) radiobiology means that chemical or physical agents, which interfere with tissue responses to low doses of radiation, could critically modulate the predicted risk. Similarly, the "health" of the organism could determine the effect of a given low dose by enabling or disabling a critical response. These issues will be discussed.

  13. Kinetic transcriptomic approach revealed metabolic pathways and genotoxic-related changes implied in the Arabidopsis response to ionising radiations.

    PubMed

    Gicquel, Morgane; Taconnat, Ludivine; Renou, Jean-Pierre; Esnault, Marie-Andrée; Cabello-Hurtado, Francisco

    2012-10-01

    Plants exposed to ionising radiation (IR) have to face direct and indirect (oxidative stress) deleterious effects whose intensity depends on the dose applied and led to differential genome regulation. Transcriptomic analyses were conducted with CATMA microarray technology on Arabidopsis thaliana plantlets, 2 and 26h after exposure to the IR doses 10Gy and 40Gy. 10Gy treatment seemed to enhance antioxidative compound biosynthetic pathways whereas the 40Gy dose up-regulated ROS-scavenging enzyme genes. Transcriptomic data also highlighted a differential regulation of chloroplast constituent genes depending on the IR dose, 10Gy stimulating and 40Gy down-regulating. This probable 40Gy decrease of photosynthesis could help for the limitation of ROS production and may be coupled with programmed cell death (PCD)/senescence phenomena. Comparisons with previous transcriptomic studies on plants exposed to a 100Gy dose revealed 60 dose-dependent up-regulated genes, including notably cell cycle checkpoints to allow DNA repairing phenomena. Furthermore, the alteration of some cellular structure related gene expression corroborated a probable mitotic arrest after 40Gy. Finally, numerous heat-shock protein and chaperonin genes, known to protect proteins against stress-dependent dysfunction, were up-regulated after IR exposure. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  14. Effect of ionising radiation on polyphenolic content and antioxidant potential of parathion-treated sage (Salvia officinalis) leaves.

    PubMed

    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.

  15. The annual effective dose from natural sources of ionising radiation in Canada.

    PubMed

    Grasty, R L; LaMarre, J R

    2004-01-01

    A review and analysis of published information combined with the results of recent gamma ray surveys were used to determine the annual effective dose to Canadians from natural sources of radiation. The dose due to external radiation was determined from ground gamma ray surveys carried out in the cities of Toronto, Ottawa, Montreal and Winnipeg and was calculated to be 219 microSv. A compilation of airborne gamma ray data from Canada and the United States shows that there are large variations in external radiation with the highest annual outdoor level of 1424 microSv being found in northern Canada. The annual effective inhalation dose of 926 microSv from 222Rn and 220Rn was calculated from approximately 14,000 measurements across Canada. This value includes a contribution of 128 microSv from 222Rn in the outdoor air together with 6 microSv from long-lived uranium and thorium series radionuclides in dust particles. Based on published information, the annual effective dose due to internal radioactivity is 306 microSv. A program developed by the Federal Aviation Administration was used to calculate a population-weighted annual effective dose from cosmic radiation of 318 microSv. The total population-weighted average annual effective dose to Canadians from all sources of natural background radiation was calculated to be 1769 microSv but varies significantly from city to city, largely due to differences in the inhalation dose from 222Rn.

  16. Pre-Service Teachers' Subject Knowledge of and Attitudes about Radioactivity and Ionising Radiation

    ERIC Educational Resources Information Center

    Colclough, Nicholas Denys; Lock, Roger; Soares, Allan

    2011-01-01

    This study focussed on secondary school (11-18 years) pre-service teachers' (n = 73) knowledge of and attitudes towards risks associated with alpha, beta, and gamma radiations. A multi-method approach was used with physics, chemistry, biology, and history graduates undertaking the one-year initial teacher training, Post Graduate Certificate in…

  17. Pre-Service Teachers' Subject Knowledge of and Attitudes about Radioactivity and Ionising Radiation

    ERIC Educational Resources Information Center

    Colclough, Nicholas Denys; Lock, Roger; Soares, Allan

    2011-01-01

    This study focussed on secondary school (11-18 years) pre-service teachers' (n = 73) knowledge of and attitudes towards risks associated with alpha, beta, and gamma radiations. A multi-method approach was used with physics, chemistry, biology, and history graduates undertaking the one-year initial teacher training, Post Graduate Certificate in…

  18. Direct estimates of cancer mortality due to low doses of ionising radiation: an international study. IARC Study Group on Cancer Risk among Nuclear Industry Workers.

    PubMed

    1994-10-15

    When setting standards for protection against ionising radiation it has been usual to extrapolate from experience with high-dose short-term exposure--studies based on atom bomb survivors and patients exposed to radiation therapeutically. Those who work in the nuclear industry are exposed to low-level predominantly gamma radiation for longer periods, and provide an alternative direct source of information. We have combined mortality data from seven cohort studies on nearly 96,000 nuclear industry workers monitored for external radiation in Canada, UK, and USA to assess directly the carcinogenic effects of protracted low-dose exposure to ionising radiation. The excess relative risk for death from leukaemia, excluding chronic lymphocytic leukaemia, was 2.2 per Sv (90% Cl 0.1 to 5.7). This estimate is intermediate between the linear estimate of 3.7 per Sv and the linear-quadratic estimate (as used in recent leukaemia risk assessments) of 1.4 per Sv derived from Japanese atomic bomb survivors' data. The excess relative risk for death from all cancers, excluding leukaemia, was -0.07 per Sv (90% Cl -0.4 to 0.3). This estimate is consistent with a range of risks varying from negative to nearly twice those estimated from atomic bomb survivors (0.18 per Sv). These are the most precise direct estimates so far made of carcinogenic risk after protracted exposure to low-dose ionising radiation. They provide little evidence that the estimates that form the basis of current radiation protection recommendations are appreciably in error.

  19. Uncertainties in estimating health risks associated with exposure to ionising radiation.

    PubMed

    Preston, R Julian; Boice, John D; Brill, A Bertrand; Chakraborty, Ranajit; Conolly, Rory; Hoffman, F Owen; Hornung, Richard W; Kocher, David C; Land, Charles E; Shore, Roy E; Woloschak, Gayle E

    2013-09-01

    The information for the present discussion on the uncertainties associated with estimation of radiation risks and probability of disease causation was assembled for the recently published NCRP Report No. 171 on this topic. This memorandum provides a timely overview of the topic, given that quantitative uncertainty analysis is the state of the art in health risk assessment and given its potential importance to developments in radiation protection. Over the past decade the increasing volume of epidemiology data and the supporting radiobiology findings have aided in the reduction of uncertainty in the risk estimates derived. However, it is equally apparent that there remain significant uncertainties related to dose assessment, low dose and low dose-rate extrapolation approaches (e.g. the selection of an appropriate dose and dose-rate effectiveness factor), the biological effectiveness where considerations of the health effects of high-LET and lower-energy low-LET radiations are required and the transfer of risks from a population for which health effects data are available to one for which such data are not available. The impact of radiation on human health has focused in recent years on cancer, although there has been a decided increase in the data for noncancer effects together with more reliable estimates of the risk following radiation exposure, even at relatively low doses (notably for cataracts and cardiovascular disease). New approaches for the estimation of hereditary risk have been developed with the use of human data whenever feasible, although the current estimates of heritable radiation effects still are based on mouse data because of an absence of effects in human studies. Uncertainties associated with estimation of these different types of health effects are discussed in a qualitative and semi-quantitative manner as appropriate. The way forward would seem to require additional epidemiological studies, especially studies of low dose and low dose

  20. Effect of radiation-induced charge accumulation on build-up cap on the signal current from an ionisation chamber.

    PubMed

    Takata, N; Morishita, Y

    2011-04-01

    The signal current from a thimble ionisation chamber with a build-up cap made of an insulator decreases by about 0.41 % after being irradiated for 17 h at an air kerma rate of 41 Gy h(-1) by a collimated (60)Co gamma-ray beam in air. In contrast, the signal current remains constant when the thimble ionisation chamber is irradiated in a water phantom. During irradiation, positive charge is considered to accumulate near the outer surface of the build-up cap where electron equilibrium is not achieved. Secondary electrons travelling in the build-up cap and the chamber wall toward the ionisation volume are decelerated by the electric field generated by the positive charge. Consequently, the signal current decreases with increasing charge accumulation because some secondary electrons are prevented from entering the ionisation volume. In the water phantom, electron equilibrium is established in and around the ionisation chamber and charge does not accumulate. To confirm this hypothesis, the signal current was measured for an ionisation chamber in air with a build-up cap wrapped with Al foil and covered with PMMA tubes. Electron equilibrium was established over the build-up cap because the tubes were thicker than the secondary electron range. The signal current decreased with increasing positive voltage applied to the Al foil. It was estimated from the results that positive charges equivalent to a voltage of over 6 kV applied to the Al foil accumulated during irradiation. The signal current was also measured for an ionisation chamber with a metal build-up cap and for an ionisation chamber with a wall and build-up cap made of conductive plastic.

  1. Triage, monitoring and dose assessment for people exposed to ionising radiation following a malevolent act.

    PubMed

    Etherington, G; Rothkamm, K; Shutt, A L; Youngman, M J

    2011-03-01

    The part played by individual monitoring within the context of the overall response to incidents involving the malevolent use of radiation or radioactive material is discussed. The main objectives of an individual monitoring programme are outlined, and types of malevolent use scenario briefly described. Some major challenges facing those with responsibilities for planning the monitoring response to such an incident are identified and discussed. These include the need for rapid selection and prioritisation of people for individual monitoring by means of an effective triage system; the need for rapid initiation of individual monitoring; problems associated with monitoring large numbers of people; the particular difficulties associated with incidents involving pure-beta and alpha-emitting radionuclides; the need for techniques that can provide retrospective estimates of external radiation exposures rapidly and the need for rapid interpretation of contamination monitoring data. The paper concludes with a brief review of assistance networks and relevant international projects planned or currently underway.

  2. Inter-comparison of safety culture within selected practices in Ghana utilising ionising radiation.

    PubMed

    Faanu, A; Schandorf, C; Darko, E O; Boadu, M; Emi-Reynolds, G; Awudu, A R; Gyekye, P K; Kpeglo, D O

    2010-12-01

    The safety culture of selected practices and facilities in Ghana utilising radiation sources or radiation emitting devices has been assessed using a performance indicator, which provided status information on management and operating staff commitment to safety. The questionnaire was based on the following broad areas: general safety considerations, safety policy at the facility level, safety practices at the facility level, definition of responsibility, staff training, safety of the physical structure of the facility and the emergency plans. The analysis showed that the percentage levels of commitment to safety for the respective practices are as follows: conventional radiography, 23.3-90.0%; research reactor, 73.3%; gamma irradiation facility, 53.3%; radiotherapy, 76.7%; X-ray scanner, 80.0%; gamma scanner, 76.7%; industrial radiography 86.7% and nuclear density practice, 78%. None of the practices or facilities was able to satisfy all the requirements that will ensure a 100% level of safety culture.

  3. Trends in hospital admissions for Varicella and Zoster viruses in England, 2001/2002-2010/2011: time trend study.

    PubMed

    Abdalrahman, Bayad; Laverty, Anthony A; Beckett, Gail; Majeed, Azeem

    2015-01-01

    Varicella and Herpes Zoster are common infectious diseases. Various studies have estimated rates of infection for both manifestations of these infections; however rates of hospital admissions across the country have not previously been described. This paper presents data on hospital admissions in England for Varicella and Herpes Zoster from 2001/2002 to 2010/2011. Time trends study of all hospital admissions for Varicella and Herpes Zoster from 2001/2002 to 2010/2011 in England. Hospital admissions across England from 2001/2002 to 2010/2011. We included all patients admitted to hospital from 2001/2002 to 2010/2011 diagnosed with Varicella and Zoster according to the International Classification of Diseases version 10 (ICD-10). The main outcome measures were admission rates by year and diagnosis and age-specific admission rates for Varicella and Zoster from 2001/2002 to 2010/2011. We analysed data from Hospital Episode Statistics which include patient characteristics such as age which was used here in order to standardise rates to the relevant population. We also used mid-year population estimates from the Office for National Statistics for standardisation purposes. All analyses were conducted using Stata v12.0. The hospital admission rate for Varicella cases has risen by 1.8% over the 10-year study period. While the overall admission rates for Herpes Zoster have decreased by 4% from 2001/2002 levels. The vast majority of Varicella and Zoster admissions were not associated with any complications. The introduction of Herpes Zoster vaccine is anticipated to decrease hospital admissions in older age groups further. A repeat of this study after a further period of time would help to evaluate the impact of the introduction of Herpes Zoster vaccine in England on hospital admissions.

  4. Non-fluoroscopic navigation systems for radiofrequency catheter ablation for supraventricular tachycardia reduce ionising radiation exposure

    PubMed Central

    See, Jason; Amora, Jonah L; Lee, Sheldon; Lim, Paul; Teo, Wee Siong; Tan, Boon Yew; Ho, Kah Leng; Lee, Chee Wan; Ching, Chi Keong

    2016-01-01

    INTRODUCTION The use of non-fluoroscopic systems (NFS) to guide radiofrequency catheter ablation (RFCA) for the treatment of supraventricular tachycardia (SVT) is associated with lower radiation exposure. This study aimed to determine if NFS reduces fluoroscopy time, radiation dose and procedure time. METHODS We prospectively enrolled patients undergoing RFCA for SVT. NFS included EnSite™ NavX™ or CARTO® mapping. We compared procedure and fluoroscopy times, and radiation exposure between NFS and conventional fluoroscopy (CF) cohorts. Procedural success, complications and one-year success rates were reported. RESULTS A total of 200 patients over 27 months were included and RFCA was guided by NFS for 79 patients; those with atrioventricular nodal reentrant tachycardia (AVNRT), left-sided atrioventricular reentrant tachycardia (AVRT) and right-sided AVRT were included (n = 101, 63 and 36, respectively). Fluoroscopy times were significantly lower with NFS than with CF (10.8 ± 11.1 minutes vs. 32.0 ± 27.5 minutes; p < 0.001). The mean fluoroscopic dose area product was also significantly reduced with NFS (NSF: 5,382 ± 5,768 mGy*cm2 vs. CF: 21,070 ± 23,311 mGy*cm2; p < 0.001); for all SVT subtypes. There was no significant reduction in procedure time, except for left-sided AVRT ablation (NFS: 79.2 minutes vs. CF: 116.4 minutes; p = 0.001). Procedural success rates were comparable (NFS: 97.5% vs. CF: 98.3%) and at one-year follow-up, there was no significant difference in the recurrence rates (NFS: 5.2% vs. CF: 4.2%). No clinically significant complications were observed in both groups. CONCLUSION The use of NFS for RFCA for SVT is safe, with significantly reduced radiation dose and fluoroscopy time. PMID:26805664

  5. Non-fluoroscopic navigation systems for radiofrequency catheter ablation for supraventricular tachycardia reduce ionising radiation exposure.

    PubMed

    See, Jason; Amora, Jonah L; Lee, Sheldon; Lim, Paul; Teo, Wee Siong; Tan, Boon Yew; Ho, Kah Leng; Lee, Chee Wan; Ching, Chi-Keong

    2016-07-01

    The use of non-fluoroscopic systems (NFS) to guide radiofrequency catheter ablation (RFCA) for the treatment of supraventricular tachycardia (SVT) is associated with lower radiation exposure. This study aimed to determine if NFS reduces fluoroscopy time, radiation dose and procedure time. We prospectively enrolled patients undergoing RFCA for SVT. NFS included EnSiteTM NavXTM or CARTO® mapping. We compared procedure and fluoroscopy times, and radiation exposure between NFS and conventional fluoroscopy (CF) cohorts. Procedural success, complications and one-year success rates were reported. A total of 200 patients over 27 months were included and RFCA was guided by NFS for 79 patients; those with atrioventricular nodal reentrant tachycardia (AVNRT), left-sided atrioventricular reentrant tachycardia (AVRT) and right-sided AVRT were included (n = 101, 63 and 36, respectively). Fluoroscopy times were significantly lower with NFS than with CF (10.8 ± 11.1 minutes vs. 32.0 ± 27.5 minutes; p < 0.001). The mean fluoroscopic dose area product was also significantly reduced with NFS (NSF: 5,382 ± 5,768 mGy*cm2 vs. CF: 21,070 ± 23,311 mGy*cm2; p < 0.001); for all SVT subtypes. There was no significant reduction in procedure time, except for left-sided AVRT ablation (NFS: 79.2 minutes vs. CF: 116.4 minutes; p = 0.001). Procedural success rates were comparable (NFS: 97.5% vs. CF: 98.3%) and at one-year follow-up, there was no significant difference in the recurrence rates (NFS: 5.2% vs. CF: 4.2%). No clinically significant complications were observed in both groups. The use of NFS for RFCA for SVT is safe, with significantly reduced radiation dose and fluoroscopy time. Copyright © Singapore Medical Association.

  6. Follow-up of children exposed to ionising radiation from cardiac catheterisation: the Coccinelle study

    PubMed Central

    Baysson, H.; Nkoumazok, B.; Barnaoui, S.; Réhel, J. L.; Girodon, B.; Milani, G.; Boudjemline, Y.; Bonnet, D.; Laurier, D.; Bernier, M. O.

    2015-01-01

    Cardiac catheterisation has become an essential tool in the diagnosis and treatment of children with a wide variety of congenital and acquired forms of cardiovascular disease. Despite the clear clinical benefit to the patient, radiation exposure from paediatric cardiac catheterisation procedures (CCPs) may be substantial. Given children's greater sensitivity to radiation and the longer life span during which radiation health effects can develop, an epidemiological cohort study, named Coccinelle or ‘Ladybird’ (French acronym for ‘Cohorte sur le risque de cancer après cardiologie interventionnelle pédiatrique’), is carried out in France to evaluate the risks of leukaemia and solid cancers in this population. A total number of 8000 included children are expected. Individual CCP-related doses will be assessed for each child included in the cohort. For each CCP performed, dosimetric parameters (dose–area product, fluoroscopy time and total number of cine frames) are retrieved retrospectively. Organ doses, especially to the lung, the oesophagus and the thyroid, are calculated with PCXMC software. The cohort will be followed up through linkage with French paediatric cancer registries. PMID:25833897

  7. Ionising radiation effect on the luminescence emission of inorganic and biogenic calcium carbonates

    NASA Astrophysics Data System (ADS)

    Boronat, C.; Correcher, V.; Virgos, M. D.; Garcia-Guinea, J.

    2017-06-01

    As known, the luminescence emission of mineral phases could be potentially employed for dosimetric purposes in the case of radiological terrorism or radiation accident where conventional monitoring is not available. In this sense, this paper reports on the thermo- (TL) and cathodoluminescence (CL) emission of both biogenic (common periwinkle - littorina littorera - shell made of calcite 90% and aragonite 10%) and inorganic (aragonite 100%) Ca-rich carbonates previously characterized by X-ray diffraction and Raman spectroscopy. Whereas the aragonite sample displays the main CL waveband peaked in the red region (linked to point defects), the more intense emission obtained from the common periwinkle shell appears at higher energies (mainly associated with structural defects). The UV-blue TL emission of the samples, regardless of the origin, displays (i) an acceptable ionizing radiation sensitivity, (ii) linear dose response in the range of interest (up to 8 Gy), (iii) reasonable stability of the TL signal after 700 h of storage with an initial decay of ca. 88% for the mineral sample and 60% for the biogenic sample and maintaining the stability from 150 h onwards. (iv) The tests of thermal stability of the TL emission performed in the range of 180-320 °C confirm a continuum in the trap system.

  8. Genotoxicity Induced by Foetal and Infant Exposure to Magnetic Fields and Modulation of Ionising Radiation Effects

    PubMed Central

    Udroiu, Ion; Antoccia, Antonio; Tanzarella, Caterina; Giuliani, Livio; Pacchierotti, Francesca; Cordelli, Eugenia; Eleuteri, Patrizia; Villani, Paola; Sgura, Antonella

    2015-01-01

    Background Few studies have investigated the toxicity and genotoxicity of extremely low frequency magnetic fields (ELF-MF) during prenatal and neonatal development. These phases of life are characterized by cell proliferation and differentiation, which might make them sensitive to environmental stressors. Although in vitro evidences suggest that ELF-MF may modify the effects of ionizing radiation, no research has been conducted so far in vivo on the genotoxic effects of ELF-MF combined with X-rays. Aim and methods Aim of this study was to investigate in somatic and germ cells the effects of chronic ELF-MF exposure from mid gestation until weaning, and any possible modulation produced by ELF-MF exposure on ionizing radiation-induced damage. Mice were exposed to 50 Hz, 65 μT magnetic field, 24 hours/day, for a total of 30 days, starting from 12 days post-conception. Another group was irradiated with 1 Gy X-rays immediately before ELF-MF exposure, other groups were only X-irradiated or sham-exposed. Micronucleus test on blood erythrocytes was performed at multiple times from 1 to 140 days after birth. Additionally, 42 days after birth, genotoxic and cytotoxic effects on male germ cells were assessed by comet assay and flow cytometric analysis. Results ELF-MF exposure had no teratogenic effect and did not affect survival, growth and development. The micronucleus test indicated that ELF-MF induced a slight genotoxic damage only after the maximum exposure time and that this effect faded away in the months following the end of exposure. ELF-MF had no effects on ionizing radiation (IR)-induced genotoxicity in erythrocytes. Differently, ELF–MF appeared to modulate the response of male germ cells to X-rays with an impact on proliferation/differentiation processes. These results point to the importance of tissue specificity and development on the impact of ELF-MF on the early stages of life and indicate the need of further research on the molecular mechanisms underlying

  9. Protection of the environment from ionising radiation in a regulatory context (protect): proposed numerical benchmark values.

    PubMed

    Andersson, Pål; Garnier-Laplace, Jacqueline; Beresford, Nicholas A; Copplestone, David; Howard, Brenda J; Howe, Paul; Oughton, Deborah; Whitehouse, Paul

    2009-12-01

    Criteria are needed to be able to judge the level of risk associated with dose rates estimated for non-human biota. In this paper, European guidance on the derivation of predicted no-effect chemical concentrations has been applied to appropriate radiation sensitivity data. A species sensitivity distribution fitted to the data for all species resulted in a generic predicted no-effect dose rate of 10 microGy h(-1).Currently, data are inadequate to derive screening values for separate organism groups. A second, higher, benchmark could aid in decision making by putting results into context on the scale of no effect to a risk of 'serious' effect. The need for, meaning and use of such a value needs to be debated by the wider community. This paper explores potential approaches of deriving scientific input to this debate. The concepts proposed in this paper are broadly consistent with the framework for human protection.

  10. Expression of the progenitor marker NG2/CSPG4 predicts poor survival and resistance to ionising radiation in glioblastoma.

    PubMed

    Svendsen, Agnete; Verhoeff, Joost J C; Immervoll, Heike; Brøgger, Jan C; Kmiecik, Justyna; Poli, Aurelie; Netland, Inger A; Prestegarden, Lars; Planagumà, Jesús; Torsvik, Anja; Kjersem, Anneli Bohne; Sakariassen, Per Ø; Heggdal, Jan I; Van Furth, Wouter R; Bjerkvig, Rolf; Lund-Johansen, Morten; Enger, Per Ø; Felsberg, Joerg; Brons, Nicolaas H C; Tronstad, Karl J; Waha, Andreas; Chekenya, Martha

    2011-10-01

    Glioblastoma (GBM) is a highly aggressive brain tumour, where patients respond poorly to radiotherapy and exhibit dismal survival outcomes. The mechanisms of radioresistance are not completely understood. However, cancer cells with an immature stem-like phenotype are hypothesised to play a role in radioresistance. Since the progenitor marker neuron-glial-2 (NG2) has been shown to regulate several aspects of GBM progression in experimental systems, we hypothesised that its expression would influence the survival of GBM patients. Quantification of NG2 expression in 74 GBM biopsies from newly diagnosed and untreated patients revealed that 50% express high NG2 levels on tumour cells and associated vessels, being associated with significantly shorter survival. This effect was independent of age at diagnosis, treatment received and hypermethylation of the O(6)-methylguanine methyltransferase (MGMT) DNA repair gene promoter. NG2 was frequently co-expressed with nestin and vimentin but rarely with CD133 and the NG2 positive tumour cells harboured genetic aberrations typical for GBM. 2D proteomics of 11 randomly selected biopsies revealed upregulation of an antioxidant, peroxiredoxin-1 (PRDX-1), in the shortest surviving patients. Expression of PRDX-1 was associated with significantly reduced products of oxidative stress. Furthermore, NG2 expressing GBM cells showed resistance to ionising radiation (IR), rapidly recognised DNA damage and effectuated cell cycle checkpoint signalling. PRDX-1 knockdown transiently slowed tumour growth rates and sensitised them to IR in vivo. Our data establish NG2 as an important prognostic factor for GBM patient survival, by mediating resistance to radiotherapy through induction of ROS scavenging enzymes and preferential DNA damage signalling.

  11. The long-term effects of acute exposure to ionising radiation on survival and fertility in Daphnia magna.

    PubMed

    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. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Risk of leukaemia mortality from exposure to ionising radiation in US nuclear workers: a pooled case-control study.

    PubMed

    Daniels, Robert D; Bertke, Stephen; Waters, Kathleen M; Schubauer-Berigan, Mary K

    2013-01-01

    To follow-up on earlier studies of the leukaemogenicity of occupational ionising radiation exposure. We conducted a nested case-control analysis of leukaemia mortality in a pooled cohort of US nuclear workers followed through 2005. Each case was matched to four controls on attained age. Exposures were estimated from available records. General relative risk models were used to estimate the excess relative risk (ERR) of leukaemia, excluding chronic lymphocytic (CLL), acute myeloid leukaemia, chronic myeloid leukaemia and CLL while controlling for potential confounders. Preferred exposure lags and time-windows of risks were calculated using joint maximum likelihood. Dose-response was also examined using linear, linear-quadratic, categorical and restricted cubic spline models. There were 369 leukaemia deaths in 105 245 US nuclear workers. The adjusted ERR for non-CLL leukaemia was 0.09 (95% CI -0.17 to 0.65) per 100 mGy. Elevated non-CLL risks were observed from exposures occurring 6-14 years prior to attained age of cases (ERR per 100 mGy=1.9; 95% CI <0 to 8.0). Lagged models indicated non-linearity of risk at very low (<10 mGy) and high (>100 mGy) doses, which contributed to the imprecision of results in linear models. Similar risk attenuation was not evident in time-windows-based models. Risk estimates were in reasonable agreement with previous estimates, with the temporality of non-CLL leukaemia risk as a dominant factor in dose-response analyses. Future research should focus on methods that improve evaluations of the dose-response, particularly in the low-dose range.

  13. Determination of methemoglobin in human blood after ionising radiation by EPR

    NASA Astrophysics Data System (ADS)

    Polakovs, M.; Mironova-Ulmane, N.; Pavlenko, A.; Aboltins, A.

    2015-03-01

    In the present work presents results of investigations of radiation influence on blood of patients examined by radio-isotopes diagnosis (Tc99m), blood of Chernobyl clean-up workers and human blood irradiated by LINAC using Electron Paramagnetic Resonance (EPR). The EPR spectroscopy reveals information on electronic states of transition metal ions, particularly Fe3+ in different spin states. It is shown that EPR spectra of blood of patients before examination has signal from metal-protein transferrin (g=4.3) and after administration of radioisotope proves signal of Fe3+ (methemaglobin) in the high spin state (g=6.0). The EPR spectra of Chernobyl liquidator display number of signals including low and high state of ion Fe3+ (g = 2.0 and g=6.0), and transferrin (g=4.3). The EPR spectra of irradiated human blood by LINAC (linear accelerator) have only signal Fe3+ (methemaglobin) in low-spin state with g = 2.0.

  14. Chromosome instability of HPRT-mutant subclones induced by ionising radiation of various LET.

    PubMed

    Govorun, R D; Koshlan, I V; Koshlan, N A; Krasavin, E A; Shmakova, N L

    2002-01-01

    The induction of HPRT-mutations and survival of Chinese hamster cells (line B11ii-FAF28, clone 431) were studied after irradiation by 4He and 12C-ions of various LET (20-360 keV/micrometers), produced by the U-200 heavy ion accelerator. The RBE increases with LET up to the maximum at 100-200 keV/micrometers and then decreases. Cytogenetic analysis was performed on the HPRT-mutant subclones selected from unirradiated Chinese hamster V-79 cells and from HPRT-mutant subclones that arose after exposure to gamma-rays, 1 GeV protons and 14N-ions (LET-77 keV/micrometers), produced by the synchrophasotron and the U-400M heavy ion accelerator. Slow growing mutant subclones were observed. The cytogenetic properties of individual clones were highly heterogeneous and chromosome instability was observed in both spontaneous and radiation-induced mutants. Chromosome instability was highest among spontaneous mutants and decreased with increasing LET.

  15. Pre-service Teachers' Subject Knowledge of and Attitudes about Radioactivity and Ionising Radiation

    NASA Astrophysics Data System (ADS)

    Denys Colclough, Nicholas; Lock, Roger; Soares, Allan

    2011-02-01

    This study focussed on secondary school (11-18 years) pre-service teachers' (n = 73) knowledge of and attitudes towards risks associated with alpha, beta, and gamma radiations. A multi-method approach was used with physics, chemistry, biology, and history graduates undertaking the one-year initial teacher training, Post Graduate Certificate in Education course at a university in central England. A novel research tool, involving interviews about real concrete contexts and first-hand data collection with radioactive sources, was employed to gain insights into a sub-set of the sample (n = 12) of pre-service teachers' subject knowledge of and attitudes towards risk. The subject knowledge of all the pre-service teachers was also measured using a Certainty of Response Index instrument; multiple-choice questions with associated confidence indicators. Although the physicists displayed the higher levels of knowledge, they also demonstrated limitations in their knowledge and held misconceptions such as irradiation being confused with contamination. Physics graduates hold more rational attitudes and a greater willingness to accept risk while the attitudes of graduates in the other subject disciplines are more disparate. These findings raise questions about the extent to which pre-service science and history teachers have the knowledge necessary to teach this topic. The article concludes with discussion of the implications these findings have for initial teacher training, continuing professional development needs for teachers already in the profession, and curriculum developers.

  16. Chromosome instability of HPRT-mutant subclones induced by ionising radiation of various let

    NASA Astrophysics Data System (ADS)

    Govorun, R. D.; Koshlan, I. V.; Koshlan, N. A.; Krasavin, E. A.; Shmakova, N. L.

    The induction of HPRT-mutations and survival of Chinese hamster cells (line B11ii-FAF28, clone 431) were studied after irradiation by 4He and 12C-ions of various LET (20 - 360 keV/μm), produced by the U-200 heavy ion accelerator. The RBE increases with LET up to the maximum at 100-200 keV/μm and then decreases. Cytogenetic analysis was performed on the HPRT-mutant subclones selected from unirradiated Chinese hamster V-79 cells and from HPRT- mutant subclones that arose after exposure to γ-rays, 1GeV protons and 14N-ions (LET - 77 keV/μm), produced by the synchrophasotron and the U-400M heavy ion accelerator. Slow growing mutant subclones were observed. The cytogenetic properties of individual clones were highly heterogeneous and chromosome instability was observed in both spontaneous and radiation-induced mutants. Chromosome instability was highest among spontaneous mutants and decreased with increasing LET.

  17. Abundance and diversity of aquatic macroinvertebrate communities in lakes exposed to Chernobyl-derived ionising radiation.

    PubMed

    Murphy, J F; Nagorskaya, L L; Smith, J T

    2011-07-01

    Littoral (lake shore) macroinvertebrate communities were studied in eight natural lakes affected by fallout from the Chernobyl accident. The lakes spanned a range in (137)Cs contamination from 100 to 15500 kBq m(-2) and estimated external dose rates ranged from 0.13 to 30.7 μGy h(-1). General linear models were used to assess whether abundance of individuals, taxon richness, Berger-Parker dominance and Shannon-Wiener diversity varied across the lakes. Step-wise multiple regressions were used to relate variation in total abundance, taxon richness, Berger-Parker dominance, Shannon-Wiener diversity, taxon richness within major groups of macroinvertebrates and abundance of the more common individual taxa to the measured environmental characteristics (conductivity, pH, total hardness and phosphate; lake area, lake maximum depth and total external dose) of the lakes. No evidence was found in this study that the ecological status of lake communities has been influenced by radioactive contamination from the Chernobyl accident. Indeed, the most contaminated lake, Glubokoye, contained the highest richness of aquatic invertebrates. Taxon richness in the eight study lakes varied from 22 (Svyatskoe #7) to 42 (Glubokoye) which spans a range typical for uncontaminated lakes in the region. Since (90)Sr is readily-absorbed by Mollusca, estimated dose rates to this group exceeded those for other invertebrate groups in two lakes (Perstok and Glubokoye). However this study found no association between mollusc diversity or abundance of individual snail species and variation between lakes in the external radiation dose. Indeed Glubokoye, the lake most contaminated by (90)Sr, had the highest richness of freshwater snails per sample (an average of 8.9 taxa per sample). 2011 Elsevier Ltd. All rights reserved.

  18. Ionising radiation and risk of death from leukaemia and lymphoma in radiation-monitored workers (INWORKS): an international cohort study.

    PubMed

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

    2015-07-01

    There is much uncertainty about the risks of leukaemia and lymphoma after repeated or protracted low-dose radiation exposure typical of occupational, environmental, and diagnostic medical settings. We quantified associations between protracted low-dose radiation exposures and leukaemia, lymphoma, and multiple myeloma mortality among radiation-monitored adults employed in France, the UK, and the USA. We assembled a cohort of 308,297 radiation-monitored workers employed for at least 1 year by the Atomic Energy Commission, AREVA Nuclear Cycle, or the National Electricity Company in France, the Departments of Energy and Defence in the USA, and nuclear industry employers included in the National Registry for Radiation Workers in the UK. The cohort was followed up for a total of 8.22 million person-years. We ascertained deaths caused by leukaemia, lymphoma, and multiple myeloma. We used Poisson regression to quantify associations between estimated red bone marrow absorbed dose and leukaemia and lymphoma mortality. Doses were accrued at very low rates (mean 1.1 mGy per year, SD 2.6). The excess relative risk of leukaemia mortality (excluding chronic lymphocytic leukaemia) was 2.96 per Gy (90% CI 1.17-5.21; lagged 2 years), most notably because of an association between radiation dose and mortality from chronic myeloid leukaemia (excess relative risk per Gy 10.45, 90% CI 4.48-19.65). This study provides strong evidence of positive associations between protracted low-dose radiation exposure and leukaemia. Centers for Disease Control and Prevention, Ministry of Health, Labour and Welfare of Japan, Institut de Radioprotection et de Sûreté Nucléaire, AREVA, Electricité de France, National Institute for Occupational Safety and Health, US Department of Energy, US Department of Health and Human Services, University of North Carolina, Public Health England. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Ionising radiation and risk of death from leukaemia and lymphoma in radiation-monitored workers (INWORKS): an international cohort study

    PubMed Central

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

    2015-01-01

    Summary Background There is much uncertainty about the risks of leukaemia and lymphoma after repeated or protracted low-dose radiation exposure typical of occupational, environmental, and diagnostic medical settings. We quantified associations between protracted low-dose radiation exposures and leukaemia, lymphoma, and multiple myeloma mortality among radiation-monitored adults employed in France, the UK, and the USA. Methods We assembled a cohort of 308 297 radiation-monitored workers employed for at least 1 year by the Atomic Energy Commission, AREVA Nuclear Cycle, or the National Electricity Company in France, the Departments of Energy and Defence in the USA, and nuclear industry employers included in the National Registry for Radiation Workers in the UK. The cohort was followed up for a total of 8·22 million person-years. We ascertained deaths caused by leukaemia, lymphoma, and multiple myeloma. We used Poisson regression to quantify associations between estimated red bone marrow absorbed dose and leukaemia and lymphoma mortality. Findings Doses were accrued at very low rates (mean 1·1 mGy per year, SD 2·6). The excess relative risk of leukaemia mortality (excluding chronic lymphocytic leukaemia) was 2·96 per Gy (90% CI 1·17–5·21; lagged 2 years), most notably because of an association between radiation dose and mortality from chronic myeloid leukaemia (excess relative risk per Gy 10·45, 90% CI 4·48–19·65). Interpretation This study provides strong evidence of positive associations between protracted low-dose radiation exposure and leukaemia. Funding Centers for Disease Control and Prevention, Ministry of Health, Labour and Welfare of Japan, Institut de Radioprotection et de Sûreté Nucléaire, AREVA, Electricité de France, National Institute for Occupational Safety and Health, US Department of Energy, US Department of Health and Human Services, University of North Carolina, Public Health England. PMID:26436129

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

    PubMed Central

    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

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

    PubMed

    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

    2015-10-20

    Is protracted exposure to low doses of ionising radiation associated with an increased risk of solid cancer? 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. 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. 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 with protracted radiation exposures can help strengthen the foundation for

  2. Phytosanitation with Ionising Radiation

    USDA-ARS?s Scientific Manuscript database

    This book chapter by Neil Heather and Guy Hallman, in “Pest Management and Phytosanitary Trade Barriers,” CABI Press, covers ionizing irradiation phytosanitary treatments. Although irradiation as an idea and research object has as long a phytosanitary history an any other phytosanitary treatment, c...

  3. Prevalence of Marijuana Use Disorders in the United States Between 2001-2002 and 2012-2013.

    PubMed

    Hasin, Deborah S; Saha, Tulshi D; Kerridge, Bradley T; Goldstein, Risë B; Chou, S Patricia; Zhang, Haitao; Jung, Jeesun; Pickering, Roger P; Ruan, W June; Smith, Sharon M; Huang, Boji; Grant, Bridget F

    2015-12-01

    Laws and attitudes toward marijuana in the United States are becoming more permissive but little is known about whether the prevalence rates of marijuana use and marijuana use disorders have changed in the 21st century. To present nationally representative information on the past-year prevalence rates of marijuana use, marijuana use disorder, and marijuana use disorder among marijuana users in the US adult general population and whether this has changed between 2001-2002 and 2012-2013. Face-to-face interviews conducted in surveys of 2 nationally representative samples of US adults: the National Epidemiologic Survey on Alcohol and Related Conditions (data collected April 2001-April 2002; N = 43,093) and the National Epidemiologic Survey on Alcohol and Related Conditions-III (data collected April 2012-June 2013; N = 36,309). Data were analyzed March through May 2015. Past-year marijuana use and DSM-IV marijuana use disorder (abuse or dependence). The past-year prevalence of marijuana use was 4.1% (SE, 0.15) in 2001-2002 and 9.5% (SE, 0.27) in 2012-2013, a significant increase (P < .05). Significant increases were also found across demographic subgroups (sex, age, race/ethnicity, education, marital status, income, urban/rural, and region). The past-year prevalence of DSM-IV marijuana use disorder was 1.5% (0.08) in 2001-2002 and 2.9% (SE, 0.13) in 2012-2013 (P < .05). With few exceptions, increases in the prevalence of marijuana use disorder between 2001-2002 and 2012-2013 were also statistically significant (P < .05) across demographic subgroups. However, the prevalence of marijuana use disorder among marijuana users decreased significantly from 2001-2002 (35.6%; SE, 1.37) to 2012-2013 (30.6%; SE, 1.04). The prevalence of marijuana use more than doubled between 2001-2002 and 2012-2013, and there was a large increase in marijuana use disorders during that time. While not all marijuana users experience problems, nearly 3 of 10 marijuana users

  4. Nonradioactive Ambient Air Monitoring at Los Alamos National Laboratory 2001--2002

    SciTech Connect

    E. Gladney; J.Dewart, C.Eberhart; J.Lochamy

    2004-09-01

    During the spring of 2000, the Cerro Grande forest fire reached Los Alamos National Laboratory (LANL) and ignited both above-ground vegetation and disposed materials in several landfills. During and after the fire, there was concern about the potential human health impacts from chemicals emitted by the combustion of these Laboratory materials. Consequently, short-term, intensive air-monitoring studies were performed during and shortly after the fire. Unlike the radiological data from many years of AIRNET sampling, LANL did not have an adequate database of nonradiological species under baseline conditions with which to compare data collected during the fire. Therefore, during 2001 the Meteorology and Air Quality Group designed and implemented a new air-monitoring program, entitled NonRadNET, to provide nonradiological background data under normal conditions. The objectives of NonRadNET were to: (1) develop the capability for collecting nonradiological air-monitoring data, (2) conduct monitoring to develop a database of typical background levels of selected nonradiological species in the communities nearest the Laboratory, and (3) determine LANL's potential contribution to nonradiological air pollution in the surrounding communities. NonRadNET ended in late December 2002 with five quarters of data. The purpose of this paper is to organize and describe the NonRadNET data collected over 2001-2002 to use as baseline data, either for monitoring during a fire, some other abnormal event, or routine use. To achieve that purpose, in this paper we will: (1) document the NonRadNET program procedures, methods, and quality management, (2) describe the usual origins and uses of the species measured, (3) compare the species measured to LANL and other area emissions, (4) present the five quarters of data, (5) compare the data to known typical environmental values, and (6) evaluate the data against exposure standards.

  5. Sources of food group intakes among the US population, 2001-2002.

    PubMed

    Bachman, Jessica L; Reedy, Jill; Subar, Amy F; Krebs-Smith, Susan M

    2008-05-01

    Food guides are typically built around a system of food groups. Accordingly, the US Department of Agriculture's MyPyramid includes both food groups and subgroups, as well as an allowance for discretionary calories, in its guidance. To identify the major dietary contributors to food group intake in the US population. This cross-sectional study used 2001-2002 National Health and Nutrition Examination Survey data to determine weighted population proportions for the contribution of each subgroup to its MyPyramid food group (ie, proportion), and the contribution of specific foods to the subgroups oils, solid fats, and added sugars (ie, major contributors). Food codes associated with each food were sorted into 96 categories, termed specific foods, and were linked to the MyPyramid Equivalents Database to obtain food group equivalents. In regard to proportion, dark green vegetables (6%), orange vegetables (5%), and legumes (6%) fell well short of recommended levels. Intake of whole grains (10% of total) was far below the recommendation that at least half of all grains be whole. In regard to major contributors, top sources of oils were potato chips, salad dressing, and nuts/seeds; major contributors of solid fats were grain-based desserts, cheese, and sausages. Sweetened carbonated beverages provided 37% of added sugars. Americans do not, in general, consume the most nutrient-dense forms of basic food groups, instead consuming foods that are high in solid fats and added sugars. The main culprits-the foods that contribute most to discrepancies between recommendations and actual intake-are sweetened carbonated beverages and other sweetened beverages, grain-based desserts, nonskim dairy products, and fatty meats.

  6. [Legionellosis in Poland in 2001-2002 and epidemiological situation in Europe].

    PubMed

    Stypułkowska-Misiurewicz, Hanna; Pancer, Katarzyna

    2003-01-01

    Legionnaires' disease is an infectious disease under the internationally approved surveillance agreed by members of European Working Group on Legionella Infections EWGLI. Data over 12,000 cases of legionnaires' disease from 28 countries are included in European data set for years 1993-2000. The overall incidence rate for Europe in 2000 was evaluated as 5,4 cases per million population. The cases was registered as community-acquired, nosocomial or travel often foreign travel associated. Most 2,799 (70.7%) of the cases in 1999-2001 were confirmed by detection of Legionella antigens in urine of patients or by serological findings 205 (18.1%); in them seroconversion was found in 9.5% and high titer in single serum specimen in 8.6% of cases. Culture proven were only 109 (9.6%) cases, and 1.6% of cases by other methods, PCR included. In Poland in 1997 the laboratory examination of samples for diagnosis of Legionella infections started in National Institute of Hygiene. In 2001-2002 the 290 samples were examined. Five cases were laboratory confirmed, but the results of 16 specimen examined was only presumptive positive and for 8 samples equivocal. In comparison with other european countries the number of examined samples is still much to small to find legionnaires' disease cases. The minimum 220 cases by year may be expected in Poland. To find such number the examination of antigenuria should be performed in patients with pneumonia hospitalised in intensive care units because of acute respiratory insufficiency.

  7. A system for protecting the environment from ionising radiation: selecting reference fauna and flora, and the possible dose models and environmental geometries that could be applied to them.

    PubMed

    Pentreath, R J; Woodhead, D S

    2001-09-28

    In order to demonstrate, explicitly, that the environment can be protected with respect to controlled sources of ionising radiation, it is essential to have a systematic framework within which dosimetry models for fauna and flora can be used. And because of the practical limitations on what could reasonably be modelled and the amount of information that could reasonably be obtained, it is also necessary to limit the application of such models to a 'set' of fauna and flora within a reference' context. This paper, therefore, outlines the factors that will need to be considered to select such 'reference' fauna and flora, and describes some of the factors and constraints necessary to develop the associated dosimetry models. It also describes some of the most basic environmental geometrics within which the dose models could be set in order to make comparisons amongst different radiation sources.

  8. Selective laser ionisation of radionuclide 63Ni

    NASA Astrophysics Data System (ADS)

    Tsvetkov, G. O.; D'yachkov, A. B.; Gorkunov, A. A.; Labozin, A. V.; Mironov, S. M.; Firsov, V. A.; Panchenko, V. Ya.

    2017-02-01

    We report a search for a scheme of selective laser stepwise ionisation of radionuclide 63Ni by radiation of a dye laser pumped by a copper vapour laser. A three-stage scheme is found with ionisation through an autoionising state (AIS): 3d 84s2 3F4(E = 0) → 3d 94p 1Fo3(31030.99 cm-1) → 3d 94d 2[7/2]4(49322.56 cm-1) → AIS(67707.61 cm-1) which, by employing saturated radiation intensities provides the ionisation selectivity of above 1200 for 63Ni.

  9. Cardiovascular fitness among U.S. adults: NHANES 1999-2000 and 2001-2002.

    PubMed

    Duncan, Glen E; Li, Sierra M; Zhou, Xiao-Hua

    2005-08-01

    To present information on cardiovascular fitness (estimated maximal oxygen uptake [VO2max] and cardiovascular fitness levels based on sex- and age-specific cut-points of estimated VO2max) among U.S. adults. Analysis of data on 1978 adults (20-49 yr) who had completed a submaximal exercise test, from the National Health and Nutrition Examination Survey (1999-2000 and 2001-2002), a cross-sectional health survey of a nationally representative sample of the noninstitutionalized U.S. population Estimated VO2max was significantly lower (P < 0.01) in non-Hispanic black ([mean +/- standard error] 38.2 +/- 0.7 mL x min(-1) x kg(-1)) than Mexican-American and non-Hispanic white adults (41.5 +/- 0.6 and 40.6 +/- 0.4 mL x min(-1) x kg(-1), respectively). Estimated VO2max was also significantly lower (P < 0.001) in non-Hispanic black females (33.1 +/- 0.6 mL x min(-1) x kg(-1)) than in Mexican-American and non-Hispanic white females (37.0 +/- 0.7 and 36.4 +/- 0.4 mL x min(-1) x kg(-1), respectively). The proportion of low, moderate, and high cardiovascular fitness differed (P < 0.001) among race and race-sex groups. This difference was most striking among females, where 30.9% [95% confidence interval = 23.6-38.2%] of non-Hispanic black women had a low cardiovascular fitness level, compared with only 13.5% [10.0-17.0%] of non-Hispanic white and 18.9% [14.0-23.8%] of Mexican-American women. Adults of non-Hispanic black race have lower cardiovascular fitness than other major race groups in the United States. Nearly one third of non-Hispanic black women had a low cardiovascular fitness level, suggesting that this group in particular may be at increased health risk due to low cardiovascular fitness.

  10. Ionising radiation immediately impairs synaptic plasticity-associated cytoskeletal signalling pathways in HT22 cells and in mouse brain: an in vitro/in vivo comparison study.

    PubMed

    Kempf, Stefan J; Buratovic, Sonja; von Toerne, Christine; Moertl, Simone; Stenerlöw, Bo; Hauck, Stefanie M; Atkinson, Michael J; Eriksson, Per; Tapio, Soile

    2014-01-01

    Patients suffering from brain malignancies are treated with high-dose ionising radiation. However, this may lead to severe learning and memory impairment. Preventive treatments to minimise these side effects have not been possible due to the lack of knowledge of the involved signalling pathways and molecular targets. Mouse hippocampal neuronal HT22 cells were irradiated with acute gamma doses of 0.5 Gy, 1.0 Gy and 4.0 Gy. Changes in the cellular proteome were investigated by isotope-coded protein label technology and tandem mass spectrometry after 4 and 24 hours. To compare the findings with the in vivo response, male NMRI mice were irradiated on postnatal day 10 with a gamma dose of 1.0 Gy, followed by evaluation of the cellular proteome of hippocampus and cortex 24 hours post-irradiation. Analysis of the in vitro proteome showed that signalling pathways related to synaptic actin-remodelling were significantly affected at 1.0 Gy and 4.0 Gy but not at 0.5 Gy after 4 and 24 hours. We observed radiation-induced reduction of the miR-132 and Rac1 levels; miR-132 is known to regulate Rac1 activity by blocking the GTPase-activating protein p250GAP. In the irradiated hippocampus and cortex we observed alterations in the signalling pathways similar to those in vitro. The decreased expression of miR-132 and Rac1 was associated with an increase in hippocampal cofilin and phospho-cofilin. The Rac1-Cofilin pathway is involved in the modulation of synaptic actin filament formation that is necessary for correct spine and synapse morphology to enable processes of learning and memory. We suggest that acute radiation exposure leads to rapid dendritic spine and synapse morphology alterations via aberrant cytoskeletal signalling and processing and that this is associated with the immediate neurocognitive side effects observed in patients treated with ionising radiation.

  11. NOVEL ASSOCIATIONS BETWEEN URINARY PERCHLORATE AND POTENTIALLY RELEVANT EFFECTS ON RISK FACTORS FOR HEART DISEASE BASED ON NHANES 2001-2002

    EPA Science Inventory

    Perchlorate is a widespread environmental pollutant, and is a thyroid hormone disruptor. A previous population study based on the National Health and Nutrition Examination Survey (NHANES) 2001-2002 database showed that urinary perchlorate concentrations were associated with signi...

  12. Association between Perchlorate and indirect indicators of thyroid dysfunction in NHANES 2001-2002, a Cross-Sectional, Hypothesis-Generating Study

    EPA Science Inventory

    Background: A previous study observed associations of urinary perchlorate with thyroid hormones based on the National Health and Nutrition Examination Survey (NHANES) 2001-2002. Increased levels of urinary perchlorate were associated with increased levels of thyroid stimulating h...

  13. NOVEL ASSOCIATIONS BETWEEN URINARY PERCHLORATE AND POTENTIALLY RELEVANT EFFECTS ON RISK FACTORS FOR HEART DISEASE BASED ON NHANES 2001-2002

    EPA Science Inventory

    Perchlorate is a widespread environmental pollutant, and is a thyroid hormone disruptor. A previous population study based on the National Health and Nutrition Examination Survey (NHANES) 2001-2002 database showed that urinary perchlorate concentrations were associated with signi...

  14. Association between Perchlorate and indirect indicators of thyroid dysfunction in NHANES 2001-2002, a Cross-Sectional, Hypothesis-Generating Study

    EPA Science Inventory

    Background: A previous study observed associations of urinary perchlorate with thyroid hormones based on the National Health and Nutrition Examination Survey (NHANES) 2001-2002. Increased levels of urinary perchlorate were associated with increased levels of thyroid stimulating h...

  15. Yakima Benthic Index of Biotic Integrity : Progress Report 2001-2002.

    SciTech Connect

    Gayeski, Nick

    2002-09-30

    Sample collections in project-years two and three (2001 & 2002) proceeded as planned. Twenty-eight (28) sites were sampled in 2001 between August 14 and September 12. Sites included two (2) mainstem Yakima River sites between Selah Gap and Union Gap, three (3) Yakima river sites upstream of Roza Dam, and three (3) mainstem Naches River sites between Cliffdell and the Wapatox Canal. The other twenty sites were tributary sites, including the Cle Elum River below Cle Elum Lake, lower Bumping river, and the American River at Pleasant Valley. Six (6) tributaries of second to fourth order were sampled at or near the same location at which they were sampled in 2000, as were two sites on the upper mainstem Yakima and one on the mainstem Naches. Thirty-three (33) sites were sampled in 2002 between August 12 and September 13. These included one (1) mainstem Yakima River site between Selah Gap and Union Gap, four (4) sites in the mainstem Yakima upstream of Roza Dam, and two (2) sites on the mainstem Naches between Naches and Cliffdell. The other twenty-six (26) sites were tributary sites, including one (1) site on the lower Tieton river, three (3) sites on the Bumping River (two downstream of Bumping Reservoir and one upstream), and two sites on the American River. Four (4) other sites were on smaller tributaries to the mainstem Naches, three (3) of which had been sampled in one (1) of the two preceding years, and one (1) (upper Rattlesnake Creek) that has been sampled in all three (3) years. Two (2) tributary sites in the upper Ahtanum subbasin were sampled, one (1) of which was sampled in 2000 and the other of which has been sampled in all three (3) years. One tributary (lower Wenas Creek) to the mainstem Yakima upstream of Selah Gap and downstream of Roza Dam was sampled. This was also sampled in 2001. Thirteen (13) sites were sampled in tributaries to the upper Yakima River, including two in the Teanaway subbasin one of which was sampled in 2000 and the other of which

  16. Occurrence, distribution and transport of pesticides into the Salton Sea Basin, California, 2001-2002

    USGS Publications Warehouse

    LeBlanc, L.A.; Kuivila, K.M.

    2008-01-01

    The Salton Sea is a hypersaline lake located in southeastern California. Concerns over the ecological impacts of sediment quality and potential human exposure to dust emissions from exposed lakebed sediments resulting from anticipated shrinking of shoreline led to a study of pesticide distribution and transport within the Salton Sea Basin, California, in 2001-2002. Three sampling stations-upriver, river mouth, and offshore-were established along each of the three major rivers that discharge into the Salton Sea. Large-volume water samples were collected for analysis of pesticides in water and suspended sediments at the nine sampling stations. Samples of the bottom sediment were also collected at each site for pesticide analysis. Sampling occurred in October 2001, March-April 2002, and October 2002, coinciding with the regional fall and spring peaks in pesticide use in the heavily agricultural watershed. Fourteen current-use pesticides were detected in water and the majority of dissolved concentrations ranged from the limits of detection to 151 ng/l. Diazinon, EPTC and malathion were detected at much higher concentrations (940-3,830 ng/l) at the New and Alamo River upriver and near-shore stations. Concentrations of carbaryl, dacthal, diazinon, and EPTC were higher in the two fall sampling periods, whereas concentrations of atrazine, carbofuran, and trifluralin were higher during the spring, which matched seasonal use patterns of these pesticides. Current-use pesticides were also detected on suspended and bed sediments in concentrations ranging from detection limits to 106 ng/g. Chlorpyrifos, dacthal, EPTC, trifluralin, and DDE were the most frequently detected pesticides on sediments from all three rivers. The number of detections and concentrations of suspended sediment-associated pesticides were often similar for the river upriver and near-shore sites, consistent with downstream transport of pesticides via suspended sediment. While detectable suspended sediment

  17. The effect of ionising radiation on testosterone binding globulin characteristics: correction of the protein' parameters by lipid polyene complexes of fungus Laetiporus sulfureus.

    PubMed

    Popoff, Eugene H; Kapich, Alexander N

    2010-03-01

    The aims of this work were: (i) To compare the effects of ionising radiation (IR) on testosterone binding globulin (TeBG) characteristics (serum concentration, cooperativity of androgen binding and affinity for hormone) in divergent mammalian species; (ii) to couple radiation effects with probable TeBG-parameter changes; and (iii) to investigate the prevention of these changes by fungal preparations (in particular - by lipid polyene complexes of Laetiporus sulphureus). Characteristics of TeBG were investigated in microaliquots of rat and human serum samples using [(3)H]-5 alpha-dihydrotestosterone ([(3)H]-DHT) radioligand assays after in vivo exposures to IR (external gamma-sources, incorporation of (131)I-, (137)Cs-radionuclides) at experimental and post-Chernobyl radioecological conditions (doses 0.25-2.2 Gy). Species-specific changes of TeBG parameters were found depending on the type of IR, dose and time after irradiation. Specifically children living in radionuclide contaminated regions (near Chernobyl) were found to have a decrease of positive cooperativity for the TeBG-androgen binding, a drop of TeBG levels, and a decline in hormone affinity. Screening of natural substances (from phanerogams and fungi) detected that lipid polyene complexes of the basidiomycete L. sulphureus allowed recovery of the standard features of TeBG. IR induced a depletion of TeBG from blood simultaneously with species-specific changes of TeBG, which depend on the type of radiation, the dose of radiation (from 0.25 up to 2.2 Gy), and the time after radiation. The Hill coefficient of TeBG (indicating the degree of molecular cooperativity when hormone binding) appeared to be the most radiosensitive marker of the glycoprotein activity because of it is inversely to radiation dose. There are pharmacological possibilities to restore IR-induced "declines" of TeBG's affinity and cooperativity for androgen ligand binding.

  18. InterCardioRisk: a novel online tool for estimating doses of ionising radiation to occupationally-exposed medical staff and their associated health risks.

    PubMed

    Moriña, David; Grellier, James; Carnicer, Adela; Pernot, Eileen; Ryckx, Nick; Cardis, Elisabeth

    2016-09-01

    Those working in interventional cardiology and related medical procedures are potentially subject to considerable exposure to x-rays. Two types of tissue of particular concern that may receive considerable doses during such procedures are the lens of the eye and the brain. Ocular radiation exposure results in lens changes that, with time, may progress to partial or total lens opacification (cataracts). In the early stages, such opacities do not result in visual disability; the severity of such changes tends to increase progressively with dose and time until vision is impaired and cataract surgery is required. Scattered radiation doses to the eye lens of an interventional cardiologist in typical working conditions can exceed 34 μGy min(-1) in high-dose fluoroscopy modes and 3 μGy per image during image acquisition (instantaneous rate values) when radiation protection tools are not used. A causal relation between exposure to ionising radiation and increased risk of brain and central nervous system tumours has been shown in a number of studies. Although absorbed doses to the brain in interventional cardiology procedures are lower than those to the eye lens by a factor between 3.40 and 8.08 according to our simulations, doses to both tissues are among the highest occupational radiation doses documented for medical staff whose work involves exposures to x-rays. We present InterCardioRisk, a tool featuring an easy-to-use web interface that provides a general estimation of both cumulated absorbed doses experienced by medical staff exposed in the interventional cardiology setting and their estimated associated health risks. The tool is available at http://intercardiorisk.creal.cat.

  19. Induction of adaptive response: pre-exposure of mice to 900 MHz radiofrequency fields reduces hematopoietic damage caused by subsequent exposure to ionising radiation.

    PubMed

    Cao, Yi; Xu, Qian; Jin, Zong-Da; Zhou, Zhen; Nie, Ji-Hua; Tong, Jian

    2011-07-01

    To investigate whether an adaptive response can be induced in mice which were pre-exposed to 900 MHz radiofrequency fields. Adult male Kunming mice were exposed to 900 MHz radiofrequency fields (RF) at power intensities of 12, 120 and 1200 μW/cm(2) for 1 h/day for 14 days and then subjected to whole body gamma-irradiation. The results were compared with those in unexposed control animals and those exposed to gamma-irradiation alone (without pre-exposure to RF). The extent of survival and hematopoietic tissue damage (assessed in the form of nucleated colony forming cells in the bone marrow and colony forming cells in the spleen of lethally irradiated 'recipient' mice) as well as the expression of cell cycle-related genes were investigated. The results indicated a significant increase in survival time, reduction in the hematopoietic tissue damage in RF pre-exposed mice which were gamma-irradiated (as compared with those exposed to gamma-radiation alone). This was accompanied by significantly increased expression of cell cycle-related genes, namely, cyclin-D1, cyclin-E, cyclin-DK4 and cyclin-DK2 in hematopoietic cells. Pre-exposure of mice to 900 MHz radiofrequency fields has resulted in a significant reduction in hematopoietic damage caused by subsequent exposure to ionising radiation. This phenomenon appears to be similar to that of the 'adaptive response' which is well documented in scientific literature.

  20. Faecal carriage of extended-spectrum β-lactamase-producing Enterobacteriaceae among humans in Java, Indonesia, in 2001-2002.

    PubMed

    Severin, Juliëtte A; Lestari, Endang Sri; Kloezen, Wendy; Lemmens-den Toom, Nicole; Mertaniasih, Ni Made; Kuntaman, Kuntaman; Purwanta, Marijam; Duerink, D Offra; Hadi, Usman; van Belkum, Alex; Verbrugh, Henri A; Goessens, Wil H

    2012-04-01

    To characterise commensal Escherichia coli and other Enterobacteriaceae with reduced susceptibility to cefotaxime that were collected in a large survey carried out among 3995 patients and healthy persons in two urban regions on Java, Indonesia, in 2001-2002. The putative extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae were analysed using double-disk synergy tests, isoelectric focusing, PCR assays, DNA sequencing, and pulsed-field gel electrophoresis (PFGE). On the day of discharge after five or more days of hospitalisation, at least 95 of 999 (9.5%) patients carried ESBL-positive Enterobacteriaceae as dominant faecal flora. Six patients were simultaneously colonised with E. coli and Klebsiella pneumoniae isolates with ESBL activity. On admission, only 6 of 998 (0.6%) patients were colonised. Faecal carriage of ESBL-producing Enterobacteriaceae among healthy persons or persons visiting a public health centre was not detected. The 107 ESBL-positive strains included 68 E. coli, 35 K. pneumoniae, and four other Enterobacteriaceae. bla(CTX-M-15) was the most prevalent ESBL in both E. coli (47.1%) and K. pneumoniae (45.7%), but the E. coli O25b-ST131 clone was virtually absent. Other ESBL types found were: SHV-2, -2a, -5, -12, CTX-M-3, -9, -14, and TEM-19. PFGE revealed extensive genetic diversity among the isolates. In 2001-2002, faecal carriage of ESBL-producing Enterobacteriaceae as dominant flora in Indonesia was almost exclusively hospital-associated. The presence of various bla(ESBL) genes and the extensive genetic diversity among isolates argue against a single/dominant strain outbreak. © 2012 Blackwell Publishing Ltd.

  1. Time trends and transplacental transfer of perfluorinated compounds in melon-headed whales stranded along the Japanese coast in 1982, 2001/2002, and 2006.

    PubMed

    Hart, Kimberly; Kannan, Kurunthachalam; Isobe, Tomohiko; Takahashi, Shin; Yamada, Tadasu K; Miyazaki, Nobuyuki; Tanabe, Shinsuke

    2008-10-01

    As a result of the phase-out of production of perfluorooctanesulfonyl-based compounds by a major producer, concentrations of perfluorooctanesulfonate (PFOS) in marine mammals from North American and European coastal waters have been declining since the early 2000s. Nevertheless, temporal trends in perfluorochemical (PFC) concentrations in marine mammals from Asian coastal waters have not been examined. In this study, PFCs were determined in livers of melon-headed whales (Peponocephala electra) collected along the coast of Japan, from three mass strandings that occurred during the past 25 years. Concentrations of nine PFCs were determined in livers of 48 melon-headed whales that were collected during strandings in 1982, 2001/2002, and 2006. In addition, concentrations in liver tissues obtained from two pregnant females and their fetuses were compared for determination of transplacental transfer rates of PFCs during gestation. PFOS and perfluorooctanesulfonamide (PFOSA) were the predominant PFCs found in livers of melon-headed whales collected in 1982 (n = 22). PFOS, PFOSA, perfluoroundecanoate (PFUnDA), perfluorododecanoate (PFDoDA), perfluorodecanoate (PFDA), and perfluorononanoate (PFNA) were found in whales collected in 2001/2002 (n = 21) and in 2006 (n = 5). Concentrations of PFOS and PFOSA were approximately 10-fold higher in 2001/2002 than in 1982. Whereas concentrations of PFOSA then declined by 2-fold from 2001/ 2002 to 2006, concentrations of PFOS and perfluorocarboxylates did not decline after 2001/2002. Conversely, concentrations of PFNA and PFDA increased significantly from 2001/2002 to 2006. The proportion of perfluoroalkylsulfonates in total PFC concentrations decreased from 75% in 1982 to 51% in 2006. Conversely, the contribution of perfluorocarboxylates to total PFC concentrations increased from 25% in 1982 to 49% in 2006. PFUnDA was the major perfluorocarboxylate found in whale livers collected after 2000. Analysis of paired samples of mother

  2. Leukaemia mortality and low-dose ionising radiation in the WISMUT uranium miner cohort (1946-2013).

    PubMed

    Kreuzer, Michaela; Sobotzki, Christina; Fenske, Nora; Marsh, James W; Schnelzer, Maria

    2017-03-01

    To examine the risk of death from leukaemia in relation to occupational chronic low-level external and internal radiation exposure in a cohort of 58 972 former German uranium miners with mortality follow-up from 1946 to 2013. The red bone marrow (RBM) dose from low-linear energy transfer (LET) (mainly external γ-radiation) and high-LET (mainly radon gas) radiation was estimated based on a job-exposure matrix and biokinetic/dosimetric models. Linear excess relative risks (ERR) and 95% CIs were estimated via Poisson regression for chronic lymphatic leukaemia (CLL) and non-CLL. The mean cumulative low-LET and high-LET RBM doses among the 86% radiation-exposed workers were 48 and 9 mGy, respectively. There was a positive non-significant dose-response for mortality from non-CLL (n=120) in relation to low-LET (ERR/Gy=2.18; 95% CI -0.41 to 6.37) and high-LET radiation (ERR/Gy=16.65; 95% -1.13 to 46.75). A statistically significant excess was found for the subgroup chronic myeloid leukaemia (n=31) in relation to low-LET radiation (ERR/Gy=7.20; 95% CI 0.48 to 24.54) and the subgroup myeloid leukaemia (n=99) (ERR/Gy=26.02; 95% CI 2.55 to 68.99) for high-LET radiation. The ERR/Gy tended to be about five to ten times higher for high-LET versus low-LET radiation; however, the CIs largely overlapped. Results indicate no association of death from CLL (n=70) with either type of radiation. Our findings indicate an increased risk of death for specific subtypes from non-CLL in relation to chronic low-LET and high-LET radiation, but no such relation for CLL. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  3. Cell culture conditions potentiate differences in the response to ionising radiation of peripheral blood leukocytes isolated from breast cancer patients and healthy subjects.

    PubMed

    Adzić, Miroslav; Nićiforović, Ana; Zarić, Bozidarka; Nesković-Konstantinović, Zora; Spasić, Snezana D; Jones, David R; Radojcić, Marija B

    2008-01-01

    To compare the effects of ionising radiation on leukocytes from breast cancer patients and healthy subjects ex vivo, the level of NF-kappaB and the antioxidant enzymes manganese-containing superoxide dismutase (Mn-SOD), copper/zinc-containing superoxide dismutase (CuZn-SOD) and catalase (CAT) in combination with flow cytometric analysis of CD4+ lymphocytes was performed. The level of Mn-SOD protein was significantly increased in the breast cancer study group both before (P < 0.001) and after (P < 0.001) irradiation when compared with healthy subjects. Measurements in parallel indicated that the level of CAT protein was significantly higher in the breast cancer study group after irradiation (2 Gy [P < 0.001] and 9 Gy [P < 0.05]) when compared with healthy subjects. Although the initial number of lymphocytes in the blood of breast cancer patients was not different from healthy subjects, the percentage of apoptotic CD4+ cells was significantly (P < 0.001) lower both before and after irradiation indicating that cell culture conditions induced radioresistance of CD4+ cells in the blood of breast cancer patients. The data presented in this current study indicate that brief ex vivo culture of peripheral blood leukocytes potentiates oxidative stress imposed by a breast cancer tumour.

  4. The effects of three bioreductive drugs (mitomycin C, RSU-1069 and SR4233) on cell lines selected for their sensitivity to mitomycin C or ionising radiation.

    PubMed

    Keohane, A; Godden, J; Stratford, I J; Adams, G E

    1990-05-01

    We have investigated the cross-sensitivity of a number of cell lines to three different classes of bioreductive drugs under both aerobic and hypoxic conditions. The cell lines used were selected for their sensitivity to DNA-damaging agents and fall into two groups. One group, MMC cells derived from CHO-K1 cells (Robson et al., 1985), show a range of sensitivities to mitomycin C in air. The second group, irs cells were cloned from V79 Chinese hamster fibroblasts (Jones et al., 1987) and exhibit sensitivity to ionising radiation. The sensitivity of both groups of cells to mitomycin C (MMC), RSU-1069 and SR4233 was assessed under aerobic and hypoxic conditions. No difference in aerobic or hypoxic toxicity of MMC was observed for CHO-K1 or MMC sensitive cell lines (MMC-2 and MMC-3). However, the MMC-resistant cell line (MMCr) was 10 times more sensitive under hypoxic than aerobic conditions. This suggests that MMCr cells lack or are deficient in the enzymes responsible for activating MMC under aerobic conditions compared to other MMC cells. In contrast, differential toxicities of between 3 and 30 have been observed for all CHO cells treated with RSU-1069 and SR4233. Treatment of V79 and irs cells with RSU-1069 and SR4233 also resulted in selective toxicity towards hypoxic cells. Differential toxicities between 50 and 100 were observed for V79 cells. For both RSU-1069 and SR4233, the hypoxic toxicities were similar in V79 and irs cells but in air, the radiation sensitive cells were up to 10 times more sensitive than wild type cells.

  5. The effects of three bioreductive drugs (mitomycin C, RSU-1069 and SR4233) on cell lines selected for their sensitivity to mitomycin C or ionising radiation.

    PubMed Central

    Keohane, A.; Godden, J.; Stratford, I. J.; Adams, G. E.

    1990-01-01

    We have investigated the cross-sensitivity of a number of cell lines to three different classes of bioreductive drugs under both aerobic and hypoxic conditions. The cell lines used were selected for their sensitivity to DNA-damaging agents and fall into two groups. One group, MMC cells derived from CHO-K1 cells (Robson et al., 1985), show a range of sensitivities to mitomycin C in air. The second group, irs cells were cloned from V79 Chinese hamster fibroblasts (Jones et al., 1987) and exhibit sensitivity to ionising radiation. The sensitivity of both groups of cells to mitomycin C (MMC), RSU-1069 and SR4233 was assessed under aerobic and hypoxic conditions. No difference in aerobic or hypoxic toxicity of MMC was observed for CHO-K1 or MMC sensitive cell lines (MMC-2 and MMC-3). However, the MMC-resistant cell line (MMCr) was 10 times more sensitive under hypoxic than aerobic conditions. This suggests that MMCr cells lack or are deficient in the enzymes responsible for activating MMC under aerobic conditions compared to other MMC cells. In contrast, differential toxicities of between 3 and 30 have been observed for all CHO cells treated with RSU-1069 and SR4233. Treatment of V79 and irs cells with RSU-1069 and SR4233 also resulted in selective toxicity towards hypoxic cells. Differential toxicities between 50 and 100 were observed for V79 cells. For both RSU-1069 and SR4233, the hypoxic toxicities were similar in V79 and irs cells but in air, the radiation sensitive cells were up to 10 times more sensitive than wild type cells. PMID:2110815

  6. Introduction, audit and review of guidelines for delegated authorization of nuclear medicine investigations in compliance with the Ionising Radiation (Medical Exposure) Regulations 2000.

    PubMed

    Harris, A M; Greaves, C D; Taylor, C M; Taylor, C; Segasby, C A; Tindale, W B

    2003-08-01

    The introduction of the Ionising Radiation (Medical Exposure) Regulations 2000 in Great Britain required every nuclear medicine investigation to be justified by a practitioner holding an appropriate Administration of Radioactive Substances Committee (ARSAC) certificate. The task of authorizing the radiation exposure may be performed by the practitioner (direct authorization) or delegated to an appropriately trained operator working to written guidelines approved by the practitioner (delegated authorization). In this study, we look at the process of implementation, audit and review of a set of Delegated Authorization Guidelines (DAG). The process of drafting the DAG is outlined. Following the introduction of the DAG, an audit of nuclear medicine referrals was performed at two sites for a period of 3 months. Each referral was compared with the DAG to determine whether it matched the criteria set out. If it did not match, it was further categorized as being due to: (1) insufficient referral information; or (2) clinical indication not included in the DAG. All non-matching requests were reviewed by the practitioner. Four hundred and thirty-seven of 632 (69%) referrals fitted the DAG, 12% (n=75) required clarification from the referrer before fitting with the criteria and 19% (n=120) were directly authorized by the practitioner. From those referrals that were directly authorized, some additional indications were identified and the DAG were subsequently revised. In conclusion, a delegated authorization procedure for nuclear medicine investigations can be implemented successfully. Regular audit is essential. This study identified the need to improve the format of the request card and to obtain additional referral information from the referrer.

  7. The assessment of ionising radiation impact on the cooling pond freshwater ecosystem non-human biota from the Ignalina NPP operation beginning to shut down and initial decommissioning.

    PubMed

    Mazeika, J; Marciulioniene, D; Nedveckaite, T; Jefanova, O

    2016-01-01

    The radiological doses to non-human biota of freshwater ecosystem in the Ignalina NPP cooling pond - Lake Druksiai were evaluated for several cases including the plant's operation period and initial decommissioning activities, using the ERICA 1.2 code with IAEA SRS-19 models integrated approach and tool. Among the Lake Druksiai freshwater ecosystem reference organisms investigated the highest exposure dose rate was determined for bottom fauna - benthic organisms (mollusc-bivalves, crustaceans, mollusc-gastropods, insect larvae), and among the other reference organisms - for vascular plants. The mean and maximum total dose rate values due to anthropogenic radionuclide ionising radiation impact in all investigated cases were lower than the ERICA screening dose rate value of 10 μGy/h. The main exposure of reference organisms as a result of Ignalina NPP former effluent to Lake Druksiai is due to ionizing radiation of radionuclides (60)Co and (137)Cs, of predicted releases to Lake Druksiai during initial decommissioning period - due to radionuclides (60)Co, (134)Cs and (137)Cs, and as a result of predicted releases to Lake Druksiai from low- and intermediate-level short-lived radioactive waste disposal site in 30-100 year period - due to radionuclides (99)Tc and (3)H. The risk quotient expected values in all investigated cases were <1, and therefore the risk to non-human biota can be considered negligible with the exception of a conservative risk quotient for insect larvae. Radiological protection of non-human biota in Lake Druksiai, the Ignalina NPP cooling pond, is both feasible and acceptable. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. On the Origin of Radio Emission in the X-Ray States of XTE J1650-500 during the 2001-2002 Outburst

    NASA Astrophysics Data System (ADS)

    Corbel, S.; Fender, R. P.; Tomsick, J. A.; Tzioumis, A. K.; Tingay, S.

    2004-12-01

    We report on simultaneous radio and X-ray observations of the black hole candidate XTE J1650-500 during the course of its 2001-2002 outburst. The scheduling of the observations allowed us to sample the properties of XTE J1650-500 in different X-ray spectral states, namely, the hard state, the steep power-law state, and the thermal dominant state, according to the recent spectral classification of McClintock & Remillard. The hard state is consistent with a compact jet dominating the spectral energy distribution at radio frequencies; however, the current data suggest that its contribution as direct synchrotron emission at higher energies may not be significant. In that case, XTE J1650-500 may be dominated by Compton processes (either inverse Comptonization of thermal disk photons and/or synchrotron self-Compton radiation from the base of the compact jet) in the X-ray regime. We surprisingly detect a faint level of radio emission in the thermal dominant state that may be consistent with the emission of previously ejected material interacting with the interstellar medium, similar (but on a smaller angular scale) to what was observed in XTE J1550-564 by Corbel and coworkers. Based on the properties of radio emission in the steep power-law state of XTE J1650-500 and taking into account the behavior of other black hole candidates (namely, GX 339-4, XTE J1550-564, and XTE J1859+226) while in the intermediate and steep power-law states, we are able to present a general pattern of behavior for the origin of radio emission in these two states that could be important for understanding the accretion-ejection coupling very close to the black hole event horizon.

  9. A new approach to studying the effects of ionising radiation on single cells using FTIR synchrotron microspectroscopy

    NASA Astrophysics Data System (ADS)

    Lipiec, E.; Birarda, G.; Kowalska, J.; Lekki, J.; Vaccari, L.; Wiecheć, A.; Wood, B. R.; Kwiatek, W. M.

    2013-12-01

    The effect of ionizing radiation on single cells using a proton source was investigated using Fourier transform infrared (FTIR) microspectroscopy. The prostate cancer cells (DU-145) were irradiated by a specific number (50, 200, 400, 2000 and 4000) of protons per cell. Next after fixing the cells with 70% ethanol micro-FTIR spectra were obtained using both: (a) the synchrotron radiation source with a Mercury-Cadmium-Telluride (MCT) detector and (b) a globar source with a focal plane array (FPA) detector. FTIR spectra obtained from both instrumental configurations were analyzed independently to investigate the changes in the DNA phosphodiester region (1150-950 cm-1) of irradiated and control (untreated by ionizing radiation) cells. A Principal Component Analysis (PCA) scores plot revealed distinct clusters for all groups of irradiated cells, even for those irradiated by the smallest dose of protons. The dose-dependent changes in the relative intensities of DNA peak at 970 cm-1 (ribose-phosphate skeletal motions), along with a shift of the O-P-O band corresponding to the symmetric phosphodiester stretching mode at 1090 cm-1 were observed. The results demonstrate that FTIR spectroscopy is a promising tool to investigate DNA damage in single cells and may become an important tool in assessing cell damage following radiotherapy.

  10. Trends in Food Habits and Their Relation to Socioeconomic Status among Nordic Adolescents 2001/2002-2009/2010

    PubMed Central

    Fismen, Anne-Siri; Smith, Otto Robert Frans; Torsheim, Torbjørn; Rasmussen, Mette; Pedersen Pagh, Trine; Augustine, Lilly; Ojala, Kristiina; Samdal, Oddrun

    2016-01-01

    Background In the Nordic countries, substantial policy and intervention efforts have been made to increase adolescents' consumption of fruit and vegetables and to reduce their intake of sweets and soft drinks. Some initiatives have been formulated in a Nordic collaboration and implemented at national level. In recent years, social inequalities in food habits have been attracted particular governmental interest and several initiatives addressing the socioeconomic gradient in food habits have been highlighted. However, few internationally published studies have evaluated how trends in adolescents' food habits develop in the context of Nordic nutrition policy, or have compared differences between the Nordic countries. Methods The study was based on Danish, Finnish, Norwegian and Swedish cross-sectional data from the international Health Behaviour in School-Aged Children (HBSC) study, collected via three nationally representative and comparable questionnaire surveys in 2001/2002, 2005/2006 and 2009/2010. Food habits were identified by students' consumption of fruit, vegetables, sweets and sugar sweetened soft drink. Socioeconomic status (SES) was measured with the Family Affluence Scale (FAS). Multilevel logistic regression was used to analyze the data. Results Trends in fruit consumption developed differently across countries, characterized by an increase in Denmark and Norway and more stable trends in Sweden and Finland. Vegetable consumption increased particularly in Denmark and to a lesser extent in Norway, whereas Sweden and Finland displayed stable trends. Decreased trends were observed for sweet and soft drink consumption and were similar in Norway, Sweden and Finland. Sweet consumption decreased across all survey years, whereas soft drink consumption decreased between 2001/2002–2005/2006 and was stable thereafter. Denmark displayed an increase between 2001/2002–2005/2006 followed by a similar decrease between 2005/2006–2009/2010 for both sweet and soft

  11. Trends in Food Habits and Their Relation to Socioeconomic Status among Nordic Adolescents 2001/2002-2009/2010.

    PubMed

    Fismen, Anne-Siri; Smith, Otto Robert Frans; Torsheim, Torbjørn; Rasmussen, Mette; Pedersen Pagh, Trine; Augustine, Lilly; Ojala, Kristiina; Samdal, Oddrun

    2016-01-01

    In the Nordic countries, substantial policy and intervention efforts have been made to increase adolescents' consumption of fruit and vegetables and to reduce their intake of sweets and soft drinks. Some initiatives have been formulated in a Nordic collaboration and implemented at national level. In recent years, social inequalities in food habits have been attracted particular governmental interest and several initiatives addressing the socioeconomic gradient in food habits have been highlighted. However, few internationally published studies have evaluated how trends in adolescents' food habits develop in the context of Nordic nutrition policy, or have compared differences between the Nordic countries. The study was based on Danish, Finnish, Norwegian and Swedish cross-sectional data from the international Health Behaviour in School-Aged Children (HBSC) study, collected via three nationally representative and comparable questionnaire surveys in 2001/2002, 2005/2006 and 2009/2010. Food habits were identified by students' consumption of fruit, vegetables, sweets and sugar sweetened soft drink. Socioeconomic status (SES) was measured with the Family Affluence Scale (FAS). Multilevel logistic regression was used to analyze the data. Trends in fruit consumption developed differently across countries, characterized by an increase in Denmark and Norway and more stable trends in Sweden and Finland. Vegetable consumption increased particularly in Denmark and to a lesser extent in Norway, whereas Sweden and Finland displayed stable trends. Decreased trends were observed for sweet and soft drink consumption and were similar in Norway, Sweden and Finland. Sweet consumption decreased across all survey years, whereas soft drink consumption decreased between 2001/2002-2005/2006 and was stable thereafter. Denmark displayed an increase between 2001/2002-2005/2006 followed by a similar decrease between 2005/2006-2009/2010 for both sweet and soft drink consumption. Socioeconomic

  12. The Unequal Burden of Weight Gain: An Intersectional Approach to Understanding Social Disparities in BMI Trajectories from 1986 to 2001/2002

    ERIC Educational Resources Information Center

    Ailshire, Jennifer A.; House, James S.

    2011-01-01

    The implications of recent weight gain trends for widening social disparities in body weight in the United States are unclear. Using an intersectional approach to studying inequality, and the longitudinal and nationally representative American's Changing Lives study (1986-2001/2002), we examine social disparities in body mass index trajectories…

  13. Evidence for a clonally different origin of the two cholera epidemics of 2001-2002 and 1980-1987 in South Africa.

    PubMed

    Keddy, Karen H; Nadan, Sandrama; Govind, Chetna; Sturm, A Willem

    2007-12-01

    Vibrio cholerae O1 serotype Ogawa and serotype Inaba isolates from the cholera epidemic that occurred in 2001 and 2002 in South Africa were compared with isolates of V. cholerae O1 serotype Inaba from the epidemic that occurred between 1980 and 1987. PFGE using NotI digestion was used to compare stored isolates received during the 1980s epidemic with those received during the epidemic in 2001/2002. A selected number of these isolates were then sequenced to compare the sequence of the wbeT gene in the V. cholerae O1 Ogawa strains of 2001/2002 with that in the V. cholerae O1 Inaba strains of the 1980s and 2001/2002. Isolates from the recent epidemic were shown to be related, irrespective of serotype, and had comparable banding patterns on PFGE, using NotI. They were distinctly different from those from the previous epidemic. Sequencing of the wbeT gene showed that the gene was highly conserved between the two epidemics. A single deletional mutation of an adenine residue was observed in the V. cholerae serotype Inaba isolates from the 2001/2002 epidemic, resulting in the serotype switch between the V. cholerae O1 strains from the recent epidemic. The distinct differences in PFGE patterns among isolates from the first and second epidemics exclude the possibility that the Inaba strain from the 1980s became dormant in the environment and mutated to serotype Ogawa, causing the 2001/2002 epidemic, despite the apparent consistency in the site of mutation in the Inaba serotypes between the two epidemics.

  14. Biodosimetric tools for a fast triage of people accidentally exposed to ionising radiation. Statistical and computational aspects.

    PubMed

    Ainsbury, Elizabeth A; Barquinero, J Francesc

    2009-01-01

    Consideration of statistical methodology is essential for the application of cytogenetic and other biodosimetry techniques to triage for mass casualty situations. This is because the requirement for speed and accuracy in biodosimetric triage necessarily introduces greater uncertainties than would be acceptable in day-to-day biodosimetry. Additionally, in a large scale accident type situation, it is expected that a large number of laboratories from around the world will assist and it is likely that each laboratory will use one or more different dosimetry techniques. Thus issues arise regarding combination of results and the associated errors. In this article we discuss the statistical and computational aspects of radiation biodosimetry for triage in a large scale accident-type situation. The current status of statistical analysis techniques is reviewed and suggestions are made for improvements to these methods which will allow first responders to estimate doses quickly and reliably for suspected exposed persons.

  15. Exposure of veterinary personnel to ionising radiation during bone scanning of horses by nuclear scintigraphy with 99mtechnetium methylene diphosphonate.

    PubMed

    Gatherer, M E; Faulkner, J; Voûte, L C

    2007-06-16

    The aim of this study was to compare the radiation doses received by the personnel drawing up and injecting the radiopharmaceutical and operating the nuclear scintigraphy equipment, and those restraining nine horses while they were being scanned during scintigraphic investigations of lameness. Sensitive electronic dosimeters were worn by the personnel and the doses they received during the administration of the radiopharmaceutical and during the period of image acquisition were recorded at intervals. On average, 90 per cent of the total doses were received during the period of image acquisition. There was no significant difference between the total dose received by the person who drew up and injected the radiopharmaceutical, and the person restraining the horse during its administration. However, the person holding the horse received approximately twice the dose received by the person operating the equipment during the period of image acquisition.

  16. Assessing the performance under ionising radiation of lead tungstate scintillators for EM calorimetry in the CLAS12 Forward Tagger

    NASA Astrophysics Data System (ADS)

    Fegan, S.; Auffray, E.; Battaglieri, M.; Buchanan, E.; Caiffi, B.; Celentano, A.; Colaneri, L.; D`Angelo, A.; De Vita, R.; Dormenev, V.; Fanchini, E.; Lanza, L.; Novotny, R. W.; Parodi, F.; Rizzo, A.; Sokhan, D.; Tarasov, I.; Zonta, I.

    2015-07-01

    The well-established technology of electromagnetic calorimetry using Lead Tungstate crystals has recently seen an upheaval, with the closure of one of the most experienced large-scale suppliers of such crystals, the Bogoroditsk Technical Chemical Plant (BTCP), which was instrumental in the development of mass production procedures for PWO-II, the current benchmark for this scintillator. Obtaining alternative supplies of Lead Tungstate crystals matching the demanding specifications of contemporary calorimeter devices now presents a significant challenge to detector research and development programmes. In this paper we describe a programme of assessment carried out for the selection, based upon the performance under irradiation, of Lead Tungstate crystals for use in the Forward Tagger device, part of the CLAS12 detector in Hall B at Jefferson Lab. The crystals tested were acquired from SICCAS, the Shanghai Institute of Ceramics, Chinese Academy of Sciences. The tests performed are intended to maximise the performance of the detector within the practicalities of the crystal manufacturing process. Results of light transmission, before and after gamma ray irradiation, are presented and used to calculate dk, the induced radiation absorption coefficient, at 420 nm, the peak of the Lead Tungstate emission spectrum. Results for the SICCAS crystals are compared with identical measurements carried out on Bogoroditsk samples, which were acquired for the Forward Tagger development program before the closure of the facility. Also presented are a series of tests performed to determine the feasibility of recovering radiation damage to the crystals using illumination from an LED, with such illumination available in the Forward Tagger from a light monitoring system integral to the detector.

  17. Deoxyribonucleic acid damage-associated biomarkers of ionising radiation: current status and future relevance for radiology and radiotherapy

    PubMed Central

    Rothkamm, K

    2013-01-01

    Diagnostic and therapeutic radiation technology has developed dramatically in recent years, and its use has increased significantly, bringing clinical benefit. The use of diagnostic radiology has become widespread in modern society, particularly in paediatrics where the clinical benefit needs to be balanced with the risk of leukaemia and brain cancer increasing after exposure to low doses of radiation. With improving long-term survival rates of radiotherapy patients and the ever-increasing use of diagnostic and interventional radiology procedures, concern has risen over the long-term risks and side effects from such treatments. Biomarker development in radiology and radiotherapy has progressed significantly in recent years to investigate the effects of such use and optimise treatment. Recent biomarker development has focused on improving the limitations of established techniques by the use of automation, increasing sensitivity and developing novel biomarkers capable of quicker results. The effect of low-dose exposure (0–100 mGy) used in radiology, which is increasingly linked to cancer incidences, is being investigated, as some recent research challenges the linear-no-threshold model. Radiotherapy biomarkers are focused on identifying radiosensitive patients, determining the treatment-associated risk and allowing for a tailored and more successful treatment of cancer patients. For biomarkers in any of these areas to be successfully developed, stringent criteria must be applied in techniques and analysis of data to reduce variation among reports and allow data sets to be accurately compared. Newly developed biomarkers can then be used in combination with the established techniques to better understand and quantify the individual biological response to exposures associated with radiology tests and to personalise treatment plans for patients. PMID:23659923

  18. The Multiple Timescales of Optical Variability of the Blazar 3C 279 during the 2001-2002 Outburst

    NASA Astrophysics Data System (ADS)

    Kartaltepe, Jeyhan S.; Balonek, Thomas J.

    2007-06-01

    During 2001-2002 the optically violent variable blazar 3C 279 underwent the most intense outburst seen during the entire 14 yr period that this quasar has been studied at Colgate University's Foggy Bottom Observatory. This study concentrates on ~1600 R-filter images taken during this period of activity. This data set includes 29 nights of microvariability coverage. The outburst began in 2001 March, after 3C 279 had faded to its faintest level, R=15.5, in 4 yr. The source reached its brightest level, R=12.5, in the 14 yr of our study in 2001 August, at which time it became unobservable due to its proximity to the Sun. On becoming observable again in 2001 mid-December, 3C 279 fluctuated between R=13.9 and 14.7, until a dramatic decrease in flux level in 2002 June-July brought the source back down to a level comparable to its preoutburst state. The source exhibited numerous week-long flares of approximately 1 mag during the outburst period. Superposed on these flares were night-to-night variations of up to 0.5 mag and intranight microvariability of up to 0.13 mag in 3 hr. We use visual inspection of the light curve, as well as numerical timescale analysis tools (the autocorrelation function, the structure function, and the power spectrum), to characterize the multiple timescales of variability ranging from 1.5 yr to several hours.

  19. Heat effects on DNA repair after ionising radiation: hyperthermia commonly increases the number of non-repaired double-strand breaks and structural rearrangements

    PubMed Central

    El-Awady, R. A.; Dikomey, E.; Dahm-Daphi, J.

    2001-01-01

    After ionising radiation double-strand breaks (dsb) are lethal if not repaired or misrepaired. Cell killing is greatly enhanced by hyperthermia and it is questioned here whether heat not only affects dsb repair capacity but also fidelity in a chromosomal context. dsb repair experiments were designed so as to mainly score non-homologous end joining, while homologous recombination was largely precluded. Human male G0 fibroblasts were either preheated (45°C, 20 min) or not before X-irradiation. dsb induction and repair were measured by conventional gel electrophoresis and an assay combining restriction digestion using a rare cutting enzyme (NotI) and Southern hybridisation, which detects large chromosomal rearrangements (>100 kb). dsb induction rate in an X-chromosomal NotI fragment was 4.8 × 10–3 dsb/Gy/Mb. Similar values were found for the genome overall and also when cells were preheated. After 50 Gy, fibroblasts were competent to largely restore the original restriction fragment size. Five per cent of dsb remained non-rejoined and 14% were misrejoined. Correct restitution of restriction fragments occurred preferably during the first hour but continued at a slow rate for 12–16 h. In addition, dsb appeared to misrejoin throughout the entire repair period. After hyperthermia the fractions of non-rejoined and misrejoined dsb were similarly increased to 13 and 51%, respectively. It is suggested that heat increases the probability of dsb being incorrectly rejoined but it is not likely to interfere with one dsb repair pathway in particular. PMID:11328880

  20. An evaluation of the shielding effectiveness of lead aprons used in clinics for protection against ionising radiation from novel radioisotopes.

    PubMed

    Deb, Pradip; Jamison, Robert; Mong, Lisa; U, Paul

    2015-07-01

    The purpose of this study is to evaluate the effectiveness of personal radiation shields currently worn in hospital and other diagnostic environments. This study was performed with four different radioisotopes; (18)F, (99m)Tc, (124)I and (131)I. (18)F results showed a decrease in dose with 0.5-mm Pb shielding but the reduction provided does not warrant its use clinically. (124)I testing demonstrated that dose enhancement can occur in greater shield thicknesses. PET isotope (124)I can be adequately shielded using 0.25-mm Pb equivalent aprons but any higher thickness increase the wearer's dose. As a result more shielding does not always equal more protection. The (131)I test showed that no dose reduction occurred, even when tested with up to 1.25-mm Pb equivalent shielding. Novel radioisotopes being used in the laboratory and clinic should be individually tested as each requires specific shielding testing. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  1. Short residence duration was associated with asthma but not cognitive function in the elderly: USA NHANES, 2001-2002.

    PubMed

    Shiue, Ivy

    2016-12-01

    There has been a growing interest in how the built environment affects health and well-being. Housing characteristics are associated with human health while environmental chemicals could have mediated the effects. However, it is unclear if and how residence duration might have a role in health and well-being. Therefore, the aim of the present study was to investigate the associations among residence duration, common chronic diseases, and cognitive function in older adults in a national and population-based setting. Data were extracted from the US National Health and Nutrition Examination Survey, 2001-2002, with assessment information on demographics, lifestyle factors, housing characteristics, self-reported common chronic diseases, and cognitive function by using the digit symbol substitution test from the Wechsler Adult Intelligence Scale (a measurement of attention and psychomotor speed). Statistical analyses including the chi-square test, t test, and survey-weighted general linear modeling and logistic regression modeling were performed. Residence duration was significantly associated with risk of asthma but not with other chronic disease, showing a longer stay in the same housing leading to lower risk of asthma (OR 0.43, 95%CI 0.27-0.69, P = 0.002) among the American older adults. However, having asthma was not associated with cognitive function decline. In conclusion, residence duration was found to be associated with risk of asthma but not cognitive function. Future research examining the relationship of residence duration and cognitive tests by other domains of cognitive function following asthma episodes would be suggested. For practice and policy implications, familiarity with the housing environment might help with lessening respiratory symptoms.

  2. 2001-2002 Wet Season Branchiopod Survey Report, Lawrence Livermore National Laboratory, Site 300, Alameda and San Joaquin Counties, California

    SciTech Connect

    Weber, W; Woollett, J

    2004-11-16

    Condor County Consulting on behalf of Lawrence Livermore National Laboratory (LLNL) has performed wet season surveys for listed branchiopods at Site 300, located in eastern Alameda County and western San Joaquin County. LLNL is collecting information for the preparation of an EIS covering ongoing explosives testing and related activities on Site 300. Related activities include maintenance of fire roads and annual control burns of approximately 607 hectares (1500 acres). Control burns typically take place on the northern portion of the site. Because natural branchiopod habitat is sparse on Site 300, it is not surprising that listed branchiopods were not observed during this 2001-2002 wet season survey. Although the site is large, a majority of it has topography and geology that precludes the formation of static seasonal pools. Even the relatively gentle topography of the northern half of the site contains few areas where water pools for more than two weeks. The rock outcrops found on the site did not provide suitable habitat for listed branchiopods. Most of the habitat available to branchiopods on the site is puddles that form in roadbeds and dry quickly. The one persistent pool on the site, the larger of the two modified vernal pools and the only one to fill this season, is occupied by two branchiopod species that require long-lived pools to reach maturity. In short, there is little habitat available on the site for branchiopods and most of the habitat present is generally too short-lived to support the branchiopod species that do occur at Site 300.

  3. [Biological properties of virus dengue-3 strains isolated during the epidemic ocurred in Havana, 2001-2002].

    PubMed

    Rodríguez-Roche, Rosmari; López Matilla, Liudmila; Alvarez Vera, Mayling; Morier Díaz, Luis; Guzmán Tirado, María G

    2012-01-01

    During dengue epidemics in Cuba, an increase in clinical severity with the epidemics progression in time, particularly in secondary infections, have been frequently observed. It is considered that this increase could be related with genetic changes in the circulating virus. To study some biological attributes related to strains isolated at different points of time during the dengue epidemic occurred in Havana city, 2001-2002. Nine DENV-3 strains were studied. Cytopathogenic effect, viral growth in C6/36 HT and Vero cell lines, viral plaque sizes, temperature sensitivity, neurovirulence in newborn mice and pH influence in the binding of the virus and the cell as well as in the multiplication medium were evaluated. DENV-3 strains were more cytopathogenic in Vero Cells. However, higher titres were obtained in C6/36 HT cells. All the strains showed reduction of viral titres and plaque size with temperature increasing and low neurovirulence. Basic pH favoured virus-cell binding whereas acid pH was only permissive for some strains isolated at the end of the epidemic. On the other hand, at pH 6.5-7, the viral multiplication medium favoured the growth of strains isolated at the beginning of the epidemic whereas the growth of those isolated at the endof the epidemic was noticeable at pH 7-8. This study proved the phenotypical changes among strains isolated at different points of time in the epidemic. They might be related to differences in viral fitness or in virulent potential. Nevertheless, some of the studied biological properties suggest that dengue virus-3 strains are less virulent than the Cuban dengue virus 2 strains isolated in 1997.

  4. What Caused the 2001-2002 Unrest at Cotopaxi Volcano, Ecuador? Insights from a Finite Element Based Geodetic Inversion

    NASA Astrophysics Data System (ADS)

    Hickey, J.; Gottsmann, J.; Mothes, P. A.

    2014-12-01

    A general inflation of the edifice and increased long-period/very-long-period seismicity define the 2001-2002 period of non-eruptive unrest at Cotopaxi volcano, Ecuador. This study focuses on the observed deformation - simultaneous contraction of seven baselines recorded by an electronic distance meter (EDM) network. To determine the cause of this deformation we model the system using Finite Element analysis with COMSOL Multiphysics. Our models incorporate subsurface heterogeneity, real topography and represent the source as a spheroidal cavity. This set up allows the EDM baselines to be modelled in three dimensions and account for the steep relief of the iconic stratovolcano, as opposed to analytical models that are either restricted to two dimensional EDM calculations and/or a flat Earth surface. To further assess the importance of topography, subsurface mechanics, and the 2-or-3D approach, we conduct a sensitivity analysis using both Finite Element and analytical techniques. We solve the Finite Element inverse problem with a least-squares approach, searching for the optimum location (longitude, latitude, depth) and over-pressure of the source to fit the EDM deformation data within its error. This optimization procedure was repeated for each source shape, orientation, size and aspect ratio using a series of nested parameter constraint grids. All source shapes converge on a location beneath the south to south-west of the edifice at a central depth of 0.5 - 2.0 km above sea level (summit at 5897 m). High-eccentricity oblate spheroids generally provide the best-fit to the observed data and may be interpreted as a sill-like intrusion as the cause of the deformation. Finally, additional forward Finite Element models are used to assess the implications of inelastic rheology, failure locations and gravity anomalies associated with the intrusion.

  5. Changes in US Lifetime Heroin Use and Heroin Use Disorder: Prevalence From the 2001-2002 to 2012-2013 National Epidemiologic Survey on Alcohol and Related Conditions.

    PubMed

    Martins, Silvia S; Sarvet, Aaron; Santaella-Tenorio, Julian; Saha, Tulshi; Grant, Bridget F; Hasin, Deborah S

    2017-05-01

    Heroin use is an urgent concern in the United States. Little is know about the course of heroin use, heroin use disorder, and associated factors. To examine changes in the lifetime prevalence, patterns, and associated demographics of heroin use and use disorder from 2001-2002 to 2012-2013 in 2 nationally representative samples of the US adult general population. This survey study included data from 43 093 respondents of the 2001-2002 National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) and 36 309 respondents of the 2012-2013 NESARC-III. Data were analyzed from February 2 to September 15, 2016. Lifetime heroin use and DSM-IV heroin use disorder. Among the 79 402 respondents (43.3% men; 56.7% women; mean [SD] age, 46.1 [17.9] years), prevalence of heroin use and heroin use disorder significantly increased from 2001-2002 to 2012-2013 (use: 0.33% [SE, 0.03%] vs 1.6% [SE, 0.08%]; disorder: 0.21% [SE, 0.03%] vs 0.69% [SE, 0.06%]; P < .001). The increase in the prevalence of heroin use was significantly pronounced among white (0.34% [SE, 0.04%] in 2001-2002 vs 1.90% [SE, 0.12%] in 2012-2013) compared with nonwhite (0.32% [SE, 0.05%] in 2001-2002 vs 1.05% [SE, 0.10%] in 2012-2013; P < .001) individuals. The increase in the prevalence of heroin use disorder was more pronounced among white individuals (0.19% [SE, 0.03%] in 2001-2002 vs 0.82% [SE, 0.08%] in 2012-2013; P < .001) and those aged 18 to 29 (0.21% [SE, 0.06%] in 2001-2002 vs 1.0% [0.17%] in 2012-2013; P = .01) and 30 to 44 (0.20% [SE, 0.04%] in 2001-2002 vs 0.77% [0.10%] in 2012-2013; P = .03) years than among nonwhite individuals (0.25% [SE, 0.04%] in 2001-2002 vs 0.43% [0.07%] in 2012-2013) and older adults (0.22% [SE, 0.04%] in 2001-2002 vs 0.51% [SE, 0.07%] in 2012-2013). Among users, significant differences were found across time in the proportion of respondents meeting DSM-IV heroin use disorder criteria (63.35% [SE, 4.79%] in 2001-2001 vs 42.69% [SE, 2.87%] in

  6. INTERACTION OF LASER RADIATION WITH MATTER. LASER PLASMA: Polarisation of the third harmonic generated by the pump field caused by collisions of electrons and ions in a plasma produced upon ionisation of a gas of excited hydrogen-like atoms

    NASA Astrophysics Data System (ADS)

    Silin, Viktor P.; Silin, Pavel V.

    2005-06-01

    The polarisation properties of the third harmonic of the pump field are considered in a plasma produced upon ionisation of excited hydrogen-like atoms, taking into account l degeneration. These properties depend on the degree of circular polarisation and intensity of the pump field. The threshold nature of the total circular polarisation of the third harmonic appearing in the case of partial circular polarisation of the pump is established. This effect represents the bifurcation of the total circular polarisation. The conditions required to confirm experimentally the predicted polarisation properties of radiation are discussed.

  7. Antimicrobial susceptibility to levofloxacin and other antibacterial agents among common respiratory pathogens-a Brazilian perspective from the GLOBAL Surveillance Initiative 2001-2002.

    PubMed

    Mendes, C; Kiffer, C R V; Blosser-Middleton, R S; Jones, M E; Karlowsky, J A; Barth, A; Rossi, F; Andrade, S; Sader, H S; Thornsberry, C; Sahm, D F

    2004-06-01

    The GLOBAL (Global Landscape On Bactericidal Activity of Levofloxacin) Surveillance programme monitored antimicrobial susceptibility patterns of the key respiratory tract pathogens Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis collected in Brazil during 1997-1998, 1999-2000 and 2001-2002. Penicillin and azithromycin resistance among S. pneumoniae strains increased from 1997-1998, reaching 7.9% and 9.5%, respectively, in 2001-2002. Although decreasing by 4.9% since the previous study, trimethoprim-sulphamethoxazole resistance remained high at 33.7%. Concurrent resistance to penicillin, azithromycin and trimethoprim-sulphamethoxazole was seen in 2.9% of the S. pneumoniae isolates collected. Levofloxacin remained extremely active against S. pneumoniae, with 0.3% resistance reported in 1997-1998 and 0% resistance in 1999-2000 and 2001-2002. beta-Lactamase production in H. influenzae was > 10% in all three studies, with correspondingly high rates of ampicillin resistance. Trimethoprim-sulphamethoxazole was the least active agent tested against H. influenzae, with resistance rates of > 40% recorded in all three studies. All H. influenzae isolates were susceptible to cefuroxime, ceftriaxone, azithromycin and levofloxacin. Of the M. catarrhalis isolates, 98.0% in 1997-1998, 98.0% in 1999-2000 and 81.8% in 2001-2002 were beta-lactamase-positive. The continued high prevalence of antimicrobial resistance in Brazil underscores the importance of current surveillance initiatives. Levofloxacin, a fluoroquinolone prescribed widely for respiratory tract infections, continued to show potent activity against key respiratory pathogens.

  8. Ionisation en couche K et effet biologique

    NASA Astrophysics Data System (ADS)

    L'Hoir, A.; Herve Du Penhoat, M. A.; Champion, C.; Fayard, B.; Touati, A.; Abel, F.; Politis, M. F.; Despiney-Bailly, I.; Sabatier, L.; Chetioui, A.

    1998-04-01

    Initial steps of radiation action mechanism on biological targets are still undnown. The strong correlation observed between inactivation cross sections by heavy ions and K-vacancy production cross sections has drawn the attention on this process. Although quite minor in the energy deposition of these particles, the K-ionization process gives rise to quite efficient ionization clusters. Values of K-ionization biological effectivenesses extracted from measured relative biological efficiencies of ultra soft X-rays support the idea of a major -may be a dominant- contribution of the K-vacancy process to the biological effect of heavy ions. Les étapes initiales des mécanismes d'effet biologique des radiations sont encore mal connues. La forte corrélation observée entre sections efficaces d'inactivation par ions lourds et sections efficaces d'ionisation K a attiré l'attention sur ce processus. Bien que de faible probabilité, l'ionisation K engendre des grappes d'ionisation très efficaces. Les valeurs de rendement létal extraites des efficacités biologiques relatives mesurées pour les rayonnements X ultra-mous suggèrent une contribution majeure -peut-être dominante- de l'ionisation K à l'effet biologique des ions.

  9. Assessment of Fish Habitat, Water Quality, and Selected Contaminants in Streambed Sediments in Noyes Slough, Fairbanks, Alaska, 2001-2002

    USGS Publications Warehouse

    Kennedy, Ben W.; Whitman, Matthew S.; Burrows, Robert L.; Richmond, Sharon A.

    2004-01-01

    During 2001-2002, the U.S. Geological Survey sampled streambed sediment at 23 sites, measured water quality at 26 sites, and assessed fish habitat for the entire length of Noyes Slough, a 5.5-mile slough of the Chena River in Fairbanks, Alaska. These studies were undertaken to document the environmental condition of the slough and to provide information to the public for consideration in plans to improve environmental conditions of the waterway. The availability of physical habitat for fish in the slough does not appear to be limited, although some beaver dams and shallow water may restrict movement, particularly during low flow. Elevated water temperatures in summer and low dissolved-oxygen concentrations are the principle factors adversely affecting water quality in Noyes Slough. Increased flow mitigated poor water-quality conditions and reduced the number of possible fish barriers. Flow appears to be the most prominent mechanism shaping water quality and fish habitat in Noyes Slough. Streambed sediment samples collected at 23 sites in 2001 were analyzed for 24 trace elements. Arsenic, lead, and zinc were the only trace elements detected in concentrations that exceed probable effect levels for the protection of aquatic life. The background concentration for arsenic in Noyes Slough is naturally elevated because of significant concentrations of arsenic in local bedrock and ground water. Sources of the zinc and lead contamination are uncertain, however both lead and zinc are common urban contaminants. Streambed-sediment samples from 12 sites in 2002 were analyzed for organochlorine pesticides, polychlorinated biphenyls (PCBs), and semivolatile organic compounds (SVOCs). The concentration of bis(2-ethylhexyl)phthalate of 2,600 micrograms per kilogram (?g/kg) for one sample from the site above Aurora Drive approached the aquatic-life criterion of 2,650 ?g/kg. Low concentrations of p-cresol, chrysene, and fluoranthene were detected in most of the sediment samples. The

  10. Characterization of winter foraging locations of Adélie penguins along the Western Antarctic Peninsula, 2001-2002

    NASA Astrophysics Data System (ADS)

    Erdmann, Eric S.; Ribic, Christine A.; Patterson-Fraser, Donna L.; Fraser, William R.

    2011-07-01

    In accord with the hypotheses driving the Southern Ocean Global Ocean Ecosystems Dynamics (SO GLOBEC) program, we tested the hypothesis that the winter foraging ecology of a major top predator in waters off the Western Antarctic Peninsula (WAP), the Adélie penguin ( Pygoscelis adeliae), is constrained by oceanographic features related to the physiography of the region. This hypothesis grew from the supposition that breeding colonies in the WAP during summer are located adjacent to areas of complex bathymetry where circulation and upwelling processes appear to ensure predictable food resources. Therefore, we tested the additional hypothesis that these areas continue to contribute to the foraging strategy of this species throughout the non-breeding winter season. We used satellite telemetry data collected as part of the SO GLOBEC program during the austral winters of 2001 and 2002 to characterize individual penguin foraging locations in relation to bathymetry, sea ice variability within the pack ice, and wind velocity and divergence (as a proxy for potential areas with cracks and leads). We also explored differences between males and females in core foraging area overlap. Ocean depth was the most influential variable in the determination of foraging location, with most birds focusing their effort on shallow (<200 m) waters near land and on mixed-layer (200-500 m) waters near the edge of deep troughs. Within-ice variability and wind (as a proxy for potential areas with cracks and leads) were not found to be influential variables, which is likely because of the low resolution satellite imagery and model outputs that were available. Throughout the study period, all individuals maintained a core foraging area separated from other individuals with very little overlap. However, from a year with light sea ice to one with heavy ice cover (2001-2002), we observed an increase in the overlap of individual female foraging areas with those of other birds, likely due to

  11. Trends in Alcohol Services Utilization from 1991-1992 to 2001-2002: Ethnic Group Differences in the U.S. Population

    PubMed Central

    Chartier, Karen G.; Caetano, Raul

    2011-01-01

    Background During the early 1990s in the U.S., changes to the provision and financing of alcohol treatment services included reductions in inpatient treatment services and in private sector spending for treatment. We investigated trends in alcohol services utilization over the 10-year period from 1991-1992 to 2001-2002 among U.S. Whites, Blacks and Hispanics. Method Data come from two household surveys of the U.S. adult population. The 1991-1992 National Longitudinal Alcohol Epidemiologic Survey (NLAES) and the 2001-2002 National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) conducted face-to-face interviews with a multistage cluster sample of individuals 18 years of age and older in the continental United States. Treatment utilization represented both total utilization and the use of alcohol services. Data analyses were prevalence rates and multivariate logistic regressions for lifetime utilization with drinkers and individuals with alcohol use disorders (AUD). Results From 1991-1992 to 2001-2002, drinking-related emergency room and human services use increased for drinkers, while total utilization and the use of private health professional services and mutual aid decreased for individuals with AUDs. In drinkers and individuals with AUDs, Blacks and Hispanics were less likely than Whites to use private health professional care. Hispanics with AUDs were less likely than Whites with AUDs to use alcohol or drug programs. Ethnicity interacted with alcohol severity to predict alcohol services utilization. At higher levels of alcohol severity, Blacks and Hispanics were less likely than Whites to ever use treatment and to use alcohol services (i.e., human services for Hispanic drinkers, mental health services for Blacks with AUDs, and mutual aid for Hispanics with AUDs). Conclusions Our findings showed increases from 1991-1992 to 2001-2002 in alcohol services utilization for drinkers, but reductions in utilization for individuals with AUDs. Blacks and

  12. Radiation safety.

    PubMed

    Skinner, Sarah

    2013-06-01

    Diagnostic radiology procedures, such as computed tomography (CT) and X-ray, are an increasing source of ionising radiation exposure to our community. Exposure to ionising radiation is associated with increased risk of malignancy, proportional to the level of exposure. Every diagnostic test using ionising radiation needs to be justified by clinical need. General practitioners need a working knowledge of radiation safety so they can adequately inform their patients of the risks and benefits of diagnostic imaging procedures.

  13. Trends in alcohol services utilization from 1991-1992 to 2001-2002: ethnic group differences in the U.S. population.

    PubMed

    Chartier, Karen G; Caetano, Raul

    2011-08-01

    During the early 1990s in the United States, changes to the provision and financing of alcohol treatment services included reductions in inpatient treatment services and in private sector spending for treatment. We investigated trends in alcohol services utilization over the 10-year period from 1991-1992 to 2001-2002 among U.S. whites, blacks, and Hispanics. Data come from 2 household surveys of the U.S. adult population. The 1991 to 1992 National Longitudinal Alcohol Epidemiologic Survey and the 2001 to 2002 National Epidemiologic Survey on Alcohol and Related Conditions conducted face-to-face interviews with a multistage cluster sample of individuals 18 years of age and older in the continental United States. Treatment utilization represented both total utilization and the use of alcohol services. Data analyses were prevalence rates and multivariate logistic regressions for lifetime utilization with drinkers and individuals with alcohol use disorders (AUDs). From 1991-1992 to 2001-2002, drinking-related emergency room and human services use increased for drinkers, while total utilization and the use of private health professional services and mutual aid decreased for individuals with AUDs. In drinkers and individuals with AUDs, blacks and Hispanics were less likely than whites to use private health professional care. Hispanics with AUDs were less likely than whites with AUDs to use alcohol or drug programs. Ethnicity interacted with alcohol severity to predict alcohol services utilization. At higher levels of alcohol severity, blacks and Hispanics were less likely than whites to ever use treatment and to use alcohol services (i.e., human services for Hispanic drinkers, mental health services for blacks with AUDs, and mutual aid for Hispanics with AUDs). Our findings showed increases from 1991-1992 to 2001-2002 in alcohol services utilization for drinkers, but reductions in utilization for individuals with AUDs. Blacks and Hispanics, particularly those at higher

  14. Enhancement of the antitumor activity of ionising radiation by nimotuzumab, a humanised monoclonal antibody to the epidermal growth factor receptor, in non-small cell lung cancer cell lines of differing epidermal growth factor receptor status

    PubMed Central

    Akashi, Y; Okamoto, I; Iwasa, T; Yoshida, T; Suzuki, M; Hatashita, E; Yamada, Y; Satoh, T; Fukuoka, M; Ono, K; Nakagawa, K

    2008-01-01

    The expression and activity of the epidermal growth factor receptor (EGFR) are determinants of radiosensitivity in several tumour types, including non-small cell lung cancer (NSCLC). However, little is known of whether genetic alterations of EGFR in NSCLC cells affect the therapeutic response to monoclonal antibodies (mAbs) to EGFR in combination with radiation. We examined the effects of nimotuzumab, a humanised mAb to EGFR, in combination with ionising radiation on human NSCLC cell lines of differing EGFR status. Flow cytometry revealed that H292 and Ma-1 cells expressed high and moderate levels of EGFR on the cell surface, respectively, whereas H460, H1299, and H1975 cells showed a low level of surface EGFR expression. Immunoblot analysis revealed that EGFR phosphorylation was inhibited by nimotuzumab in H292 and Ma-1 cells but not in H460, H1299, or H1975 cells. Nimotuzumab augmented the cytotoxic effect of radiation in H292 and Ma-1 cells in a clonogenic assay in vitro, with a dose enhancement factor of 1.5 and 1.3, respectively. It also enhanced the antitumor effect of radiation on H292 and Ma-1 cell xenografts in nude mice, with an enhancement factor of 1.3 and 4.0, respectively. Nimotuzumab did not affect the radioresponse of H460 cells in vitro or in vivo. Nimotuzumab enhanced the antitumor efficacy of radiation in certain human NSCLC cell lines in vitro and in vivo. This effect may be related to the level of EGFR expression on the cell surface rather than to EGFR mutation. PMID:18253126

  15. Learning for Life: The Role of Adult Literacy and Numeracy in Lifelong Learning and Socio-Economic Well-Being. Executive Summary of the ALNARC National Research Program, 2001-2002.

    ERIC Educational Resources Information Center

    Shore, Sue; Searle, Jean; Falk, Ian; Johnston, Betty; Ovens, Carolyn; Riddell, Christine

    In 2001-2002, the Adult Literacy and Numeracy Australian Research Consortium conducted 26 national investigations with findings in the following areas: (1) population competence; (2) linking literacy and numeracy into training; (3) professional support for educators and trainers; and (4) policy and systemic issues. All the projects were intended…

  16. A prospective, Internet-based study of the effectiveness and safety of influenza vaccination in the 2001-2002 influenza season.

    PubMed

    Kawai, Naoki; Ikematsu, Hideyuki; Iwaki, Norio; Satoh, Ietaka; Kawashima, Takashi; Tsuchimoto, Taizo; Kashiwagi, Seizaburo

    2003-11-07

    The effectiveness of the influenza vaccine used in the 2001-2002 influenza season in Japan was investigated in a large-scale, geographically widely distributed, Internet-based study. Data were collected from 8841 of 9902 subjects registered by 38 clinics prior to the start of influenza season. Subjects were categorized into three groups by vaccination regimen: unvaccinated, vaccinated once, and vaccinated twice. Efficacy was also analyzed for three age groups: 0-15, 16-64, and 65-104 years. Influenza-like illness (ILI) was diagnosed according to Ministry of Health (MWH, Labor and Welfare in Japan) criteria. Laboratory-confirmed influenza cases were analyzed separately. The respective vaccine efficacy in the 0-15 years group for the one- and two-dose regimens was 67.6 and 84.5% for ILI and 54.0 and 79.8% for laboratory-confirmed influenza. Influenza vaccination was also shown to be effective in subjects 16-64 years. Vaccine effectiveness was not able to be determined for the over 65 years group, probably due to an insufficient number of infected patients. These results suggest that influenza vaccination is effective for children and adults and that a two-dose regimen is superior to a single dose in children 0-15 years.

  17. Temporal trends and regional variability of 2001-2002 multiwave DENV-3 epidemic in Havana City: did Hurricane Michelle contribute to its severity?

    PubMed

    Hsieh, Ying-Hen; de Arazoza, Hector; Lounes, Rachid

    2013-07-01

    To investigate the temporal and regional variability of the 2001-2002 dengue outbreak in Havana City where 12 889 cases, mostly of DENV-3 type, were reported over a period of 7 months. A simple mathematical model, the Richards model, was used to fit the weekly reported dengue case data by municipality, in order to quantify the transmissibility and temporal changes in the epidemic in each municipality via the basic reproduction number R0 . Model fits indicate either a 2-wave or 3-wave outbreak in all municipalities. Estimates for R0 varied greatly, from 1.97 (95% CI: 1.94, 2.01), for Arroyo Naranjo, to 61.06 (60.44, 61.68), for Boyeros, most likely due to heterogeneity in community structure, geographical locations and social networking. Our results illustrate the potential impact of climatological events on disease spread, further highlighting the need to be well prepared for potentially worsening disease spread in the aftermath of natural disasters such as hurricanes/typhoons. © 2013 Blackwell Publishing Ltd.

  18. Post-wildfire recovery of water yield in the Sydney Basin water supply catchments: An assessment of the 2001/2002 wildfires

    NASA Astrophysics Data System (ADS)

    Heath, J. T.; Chafer, C. J.; van Ogtrop, F. F.; Bishop, T. F. A.

    2014-11-01

    Wildfire is a recurring event which has been acknowledged by the literature to impact the hydrological cycle of a catchment. Hence, wildfire may have a significant impact on water yield levels within a catchment. In Australia, studies of the effect of fire on water yield have been limited to obligate seeder vegetation communities. These communities regenerate from seed banks in the ground or within woody fruits and are generally activated by fire. In contrast, the Sydney Basin is dominated by obligate resprouter communities. These communities regenerate from fire resistant buds found on the plant and are generally found in regions where wildfire is a regular occurrence. The 2001/2002 wildfires in the Sydney Basin provided an opportunity to investigate the impacts of wildfire on water yield in a number of catchments dominated by obligate resprouting communities. The overall aim of this study was to investigate whether there was a difference in water yield post-wildfire. Four burnt subcatchments and 3 control subcatchments were assessed. A general additive model was calibrated using pre-wildfire data and then used to predict post-wildfire water yield using post-wildfire data. The model errors were analysed and it was found that the errors for all subcatchments showed similar trends for the post-wildfire period. This finding demonstrates that wildfires within the Sydney Basin have no significant medium-term impact on water yield.

  19. Free radical studies of components of the extracellular matrix: contributions to protection of biomolecules and biomaterials from sterilising doses of ionising radiation.

    PubMed

    Parsons, Barry J

    2017-09-04

    The purpose of the current review is show how the principles and techniques of radiation chemistry have enabled the direct reactions of free radicals with biomolecules and biomaterials to be investigated at the molecular level. In particular, the review focusses on the free radical-induced fragmentation of glycosaminoglycans. Glycosaminoglycans are large linear polysaccharides consisting of repeating disaccharide units and are important components of the extracellular matrix (ECM) either in free form (hyaluronan) or as a component of proteoglycans. Oxidative damage of the extracellular matrix components by either enzymatic or non-enzymatic pathways may have implications for the initiation and progression of a range of human diseases. These include arthritis, kidney disease, cardiovascular disease, lung disease, periodontal disease and chronic inflammation. Oxidative damage to hyaluronan by reactive oxidative species and thus the potential mechanism of damage to the ECM and its role in human pathologies is reviewed with particular focus on damage initiated by potential in vivo free radicals such as superoxide, carbonate and hydroxyl radicals. Such knowledge has also allowed radiation protecting systems to be developed so that sterilising doses of radiation can be delivered to sensitive biomolecules such as proteins and glycosaminoglycans, and also to sensitive biomaterials such as tissue allografts.

  20. Electron ionisation of sulfur dioxide.

    PubMed

    Fletcher, James D; Parkes, Michael A; Price, Stephen D

    2013-05-14

    Relative precursor-specific partial ionisation cross sections for the fragment ions formed following electron ionisation of sulfur dioxide (SO2) have been measured for the first time, from 30 to 200 eV, using time-of-flight mass spectrometry coupled with two-dimensional ion coincidence detection. These data quantify the yields of O(2+), O(+), SO(2+), S(+), O2(+), and SO(+) ions, relative to the formation of SO2(+), via single, double, and triple electron ionisation of SO2. Formation of O(2+), following electron-SO2 collisions, has been quantified for the first time. The data allow a first experimental estimate of the triple ionisation potential of SO2 (69.0 ± 3.6 eV), an energy in good agreement with a value derived in this study via computational chemistry. The triple ion combination S(+) + O(+) + O(+) is clearly detected following electron collisions with SO2 at electron energies markedly below the vertical energy for forming SO2(3 +). This observation is accounted for by the operation of a stepwise pathway to the formation of S(+) + 2O(+) which does not involve the formation of a molecular trication.

  1. Epidemiological studies of Fukushima residents exposed to ionising radiation from the Fukushima Daiichi Nuclear Power Plant prefecture--a preliminary review of current plans.

    PubMed

    Akiba, Suminori

    2012-03-01

    It is now more than six months since the beginning of the accident on 11 March 2011 at the Fukushima Daiichi Nuclear Power Plant in Japan. The Japanese government and local health authorities have started to collect the information necessary to estimate radiation doses received by those living in the area around the plant, drafted plans for the health care of residents, and started to implement some of them. This paper reviews and discusses the studies necessary for risk evaluation of cancer and non-cancer diseases, including those already planned, mainly from the view point of evaluating health risk using epidemiological approaches. In the long run, it is important to establish a cohort with a control group. Even if the cumulative doses are estimated to be so low that it is difficult to evaluate the risk of cancer and non-cancer diseases, it is necessary to conduct such a study to reassure residents. The health care programme of the Fukushima Prefecture government, including health check-ups of residents, will help to assess indirect effects of radiation exposure, including psychological problems. The success of any studies of radiation epidemiology depends on the collection of accurate information on radiation doses received by the study subjects. However, some of the dosimetry surveys were not conducted in a timely manner. (It should be recognised, though, that such a problem might have been inevitable, considering the chaotic condition after the nuclear accident.) Accurate estimation of the radiation dose received by each resident is not only important for scientific risk evaluation but also to inform each resident about his or her potential risk. Otherwise, residents will bear an undue psychological burden from uncertainties regarding their radiation exposure and its health consequences. One of other important tasks in Fukushima is the improvement of the quality of the regional cancer registry in this prefecture. It is also important to start thyroid cancer

  2. Population-based reference standards for cardiovascular fitness among U.S. adults: NHANES 1999-2000 and 2001-2002.

    PubMed

    Sanders, Leslee F; Duncan, Glen E

    2006-04-01

    To provide reference standards for cardiovascular fitness levels, using population-based estimates of estimated maximal oxygen uptake (VO2max) from a diverse sample of U.S. adults. Analysis of data from adults (20-49 yr) who completed a submaximal exercise test in the National Health and Nutrition Examination Survey 1999-2000 and 2001-2002. Estimated VO2max was categorized as low (<20th percentile), moderate (between 20th and 59th percentiles), or high (> or =60th percentile) fitness using age- and sex-specific cut-points. There were 1978 subjects, roughly 29% Mexican-American, 20% non-Hispanic black, and 51% non-Hispanic white. Using population-based sample weights, this was equivalent to 54,078,766 persons with mean (+/- SE) age, 34.4 +/- 0.3 yr; body mass index (BMI), 27.0 +/- 0.2 kg x m(-2); and estimated VO2max, 40.4 +/- 0.3 mL x min(-1) x kg(-1). There was a significant association between race and fitness level and between race and fitness level by sex (P < 0.0001). Low fitness was highest among non-Hispanic blacks (percentage (95% confidence interval): 32%, (26-38%)) compared with Mexican-Americans (22% (18-27%)) and non-Hispanic whites (18% (15-21%)), particularly among females, where 35% (28-42%) non-Hispanic black women had low fitness compared with 22% (16.3-27.4%) Mexican-American and 18% (13.7-22.4%) non-Hispanic white women. Non-Hispanic black adults have the highest percentage of low cardiovascular fitness among major race groups in the United States. On a population basis, over one third of non-Hispanic black women have low cardiovascular fitness, suggesting this group in particular may be at increased health risk due to poor fitness.

  3. Aseismic magma supply inferred from geodetic Finite Element inversions: the case of the 2001-2002 non-eruptive unrest at Cotopaxi volcano

    NASA Astrophysics Data System (ADS)

    Hickey, James; Gottsmann, Jo; Mothes, Patricia

    2015-04-01

    The complex interplay between magma supply, storage and transportation, and how these processes interact with the host rock dictate the unrest signals we observe at the surface. Mechanical modelling allows us to link our recorded geophysical signals to subsurface processes and constrain a causative mechanism. We carry out this analysis for the 2001-2002 non-eruptive unrest episode at Cotopaxi volcano, Ecuador. During this period the volcano underwent a general inflation of its iconic edifice, recorded by an Electronic Distance Meter (EDM) network, and was accompanied by increased seismicity beneath the north-east flank. To solve for the optimum deformation source parameters we use an inverse Finite Element method accounting for subsurface material heterogeneity and surface topography. The model solutions favour a shallow source beneath the south-west flank, in contradiction to the seismicity locations in the north-east. The best-fit deformation model is a small, oblate shaped source approximately 1 km above sea level with a 20 x 106 m3 volume increase. To reconcile the deformation and seismicity simultaneously further Finite Element models were employed, incorporating an additional temperature-dependent rheology. These were used to assess the viscosity of the host rock surrounding the source. By comparing the elastic and viscous timescales associated with a small magma intrusion (implied by the best-fit deformation source in the south-west), we can infer this process occurred aseismically. To explain the recorded seismicity in the north-east we propose a mechanism of fluid migration from the south-west to the north-east along fault systems. Our analysis further shows that if future unrest crises are accompanied by measurable seismicity around the deformation source, this could indicate a higher magma supply rate and a critical level of unrest with increased likelihood of a forthcoming eruption. This research received funding through the EC FP7 "VUELCO" (#282759

  4. Distribution and community structure of euphausiids in the Southern Ocean along the 140°E meridian during the austral summer 2001/2002

    NASA Astrophysics Data System (ADS)

    Nishikawa, Jun; Toczko, Sean; Hosie, Graham W.

    2010-04-01

    The abundance, biomass, diversity and community structure of euphausiids in the Southern Ocean along the 140°E meridian from latitudes 47°S-65°S were examined by RMT8 from 0 to ca. 1000 m during the 2001/2002 austral summer. Both total abundance and biomass of euphausiids were much higher in the south of the southern branch of the Polar Front (PF-S) located at 60°S-61°S than in the northern part, corresponding with higher chlorophyll a concentrations. Eleven species of euphausiids were collected from the research areas: 2 species of Thysanoëssa, 6 of Euphausia, and a single species each of Thysanopoda, Bentheuphausia and Nematoselis. In Euphausia and Thysanoëssa, clear horizontal distribution patterns enabled the classification of each species into one of 3 different types: species occurring only at stations north of the PF, species occurring in a broad distribution from south of the PF-S to the south of the Southern Boundary (SB) of the Antarctic Circumpolar Current, and species occurring only south of the SB. The latitudinal zonations occurrence and peak abundance were evident for all species. Hierarchical cluster analysis by species and station resulted in the identification of 2 distinct communities of euphausiids: community I comprised the three stations north of the PF where both euphausiid abundance and biomass were relatively low, and 2 species, Thysanopoda acutifrons and Thysanoëssa gregaria dominated, community II comprised the southern five stations where abundance and biomass were high and Euphausia frigida, E. superba and Thysanoëssa macrura were numerically dominant. Among the five oceanographic fronts within the research area, the PF (either south or north) appears to be the important biogeographical boundary separating abundance, biomass, and the community structure of euphausiids.

  5. Levels of 25 trace elements in high-volume air filter samples from Seville (2001-2002): Sources, enrichment factors and temporal variations

    NASA Astrophysics Data System (ADS)

    Enamorado-Báez, S. M.; Gómez-Guzmán, J. M.; Chamizo, E.; Abril, J. M.

    2015-03-01

    The measurement of trace element concentration in aerosols is of interest for environmental studies and for human health assessment. The temporal variability of total suspended particles (TSP) and its elemental composition in Seville, in SW Spain, is of particular complexity since Atlantic air masses and Saharan Dust Intrusions (SDI) overlap to local natural and anthropogenic sources. This paper is aimed to study the temporal evolution (in a monthly basis) of the concentrations of 25 trace elements, determined by ICP-MS, in high-volume air filter samples from Seville, covering a two-year period: 2001-2002. The mean TSP value for this period was 79.7 μg m- 3 and showed peak values in August 2001 and June 2002, likely related to SDI. Enrichment factors (EF) for Se, Sb and Zn and Pb were above 100, which revealed their anthropogenic sources. The comparison among EF from Seville and Huelva, a highly industrialized city nearby Seville, showed higher levels of anthropogenic elements there than in Seville. Simulations of the transport/dispersion of pollutants starting in Huelva confirm that air pollutants can reach Seville in the course of around 6 hours although they do not contribute significantly to the levels found in this city. A significant temporal correlation was found between elements which have a common source, being crustal (Al, Ti, Be, Co, Cs, Fe, Cr, Mn, U, Sr and Th) or anthropogenic sources (Zn, Pb, Cd). The temporal variations of those crustal elements are similar and related with the TSP levels for both years, with the clearly visible peaks probably related with the Saharan dust intrusion.

  6. Monitoring radiation belt particle precipitation - automatic detection of enhanced transient ionisation in the lower plasmasphere using subionospheric narrow band VLF signals

    NASA Astrophysics Data System (ADS)

    Steinbach, P.; Lichtenberger, J.; Ferencz, Cs.

    2009-04-01

    Signals of naval VLF transmitters, propagating long distances along the Earth-ionosphere waveguide (EIWG) have been widely applied as effective tools for monitoring transient ionization at mesospheric altitudes. Perturbations in recorded amplitude and/or phase data series of stable frequency signals may refer to the effect of transient enhanced ionization in the EIWG, due to e.g. loss-cone precipitation of trapped energetic electrons (Carpenter et al., 1984, Dowden and Adams, 1990), burst of solar plasma particles (Clilverd et al., 2001). The contribution of precipitating particles are thought to be substantial in certain Sun-to-Earth energy flow processes in the upper atmosphere (Rodger et al., 2005). Narrow band VLF measuring network has been set up, developed and operated in Hungary, running in the last decade almost continuously, dedicated to monitor ionization enhancement regions along numerous transmitter-receiver paths. This setup is based on Omnipal and Ultra-MSK equipment, logging amplitude and phase data of received signals, sampled at frequencies of selected VLF transmitters. Signal trajectories, selected for recording represent proper configuration to survey transient ionization caused by energetic particles in the sub-polar region, such as effect of scattered particles of the inner radiation belt. Reprocessing of the mass archived recordings has been started using a newly developed signal processing code, detecting and classifying different sort of perturbations automatically on narrow band VLF series. Occurrence rates, daily and seasonal variation, statistics of transient ionization enhancements, their geographic distribution within the surveyed range and time period, and correlation with intense geomagnetic and/or Solar event is yielded by this analysis. References: Carpenter, D.L., Inan, U.S., Trimpi, M.L., Helliwell, R.A., and Katsufrakis, J.P.: Perturbations of subionospheric LF and MF signals due to whistler-induced electron precipitation burst

  7. Optimisation of radiolysis of Reactive Red 120 dye in aqueous solution using ionising (60)Co gamma radiation by response surface methodology.

    PubMed

    Padmanaban, V C; Giri Nandagopal, M S; Achary, Anant; Vasudevan, V N; Selvaraju, N

    2016-01-01

    In recent years, employing radiation technology is gaining great interest in degradation of industrial effluents. In this work the possibility of using gamma irradiation to degrade Reactive Red 120 (C.I.292775) was explored. The effects of pH, dose of gamma irradiation and concentration of dye were examined and their interaction were also established based on their response. For the analysis and optimisation of variables, three factor three level Box-Wilson face centred central composite design (CCF) was used. Analysis of variance with R(2) = 0.9988, adjusted R(2) = 0.9981 and the adequate precision value of 122.303 indicates that the CCF model can be used. The coefficient of variation (0.54%) indicates the reliability of the model. The dose of gamma irradiation (kGy) and the concentration of dye (mg/L) showed significant effects on the degradation of RR 120, while a difference of 6 to 10% degradation was observed in extending the pH towards the acid or alkali range from pH 7.00. The maximum concentration of dye degraded was observed as 347.509 mg/L at initial pH: 7.0, dose of gamma irradiation: 5.94 kGy and initial concentration of dye: 500 mg/L. This predicted value was found to be in agreement with the experimental value on the optimised conditions.

  8. INTERACTION OF LASER RADIATION WITH MATTER. LASER PLASMA: Change in the ionisation state of a near-surface laser-produced aluminium plasma in double-pulse ablation modes

    NASA Astrophysics Data System (ADS)

    Burakov, V. S.; Bokhonov, A. F.; Nedel'ko, M. I.; Tarasenko, N. V.

    2003-12-01

    The near-surface plasma produced upon irradiation of an aluminium target by two successive laser pulses with nonresonance and resonance wavelengths is studied by the spectroscopic and probe-assisted methods. The feasibility of increasing the ion fraction in the laser-produced plasma in double-pulse ablation modes is demonstrated. The conditions are determined under which processes on the surface as well as selective excitation and ionisation in the plasma have a determining effect on the formation of its ionisation state.

  9. Ionising sources in the coma of 67P probed by Rosetta

    NASA Astrophysics Data System (ADS)

    Heritier, Kevin; Galand, Marina; Henri, Pierre; Eriksson, Anders; Odelstad, Elias; Altwegg, Kathrin; Beth, Arnaud; Broiles, Thomas; Burch, Jim; Carr, Christopher; Cupido, Emanuele; Glassmeier, Karl-Heinz; Nilsson, Hans; Richter, Ingo; Rubin, Martin; Vallieres, Xavier; Vigren, Erik

    2017-04-01

    An ionospheric model has been developed in order to quantify the ion number density in the coma of 67P/Churyumov-Gerasimenko. The model is driven by Rosetta Orbiter Spectrometer for Ion and Neutral Analysis (ROSINA)/Cometary Pressure Sensor (COPS) neutral density and assumes isentropic expansion for the neutral density profile. The two ionisation sources considered are photo-ionisation by solar extreme ultraviolet (EUV) radiation and electron-impact ionisation. The EUV radiation is estimated from fluxes measured by the Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED)/ Solar EUV Experiment (SEE), taking into account the phase shift and the heliocentric distance ratio; between Earth and comet 67P. The electron-impact ionisation production rates are derived from Rosetta Plasma Consortium (RPC)-Ion and Electron Sensor (IES) integrated electron fluxes and corrected for the S/C potential from RPC/LAngmuir Probe (LAP) measurements. Our results are compared with in situ measurements of the plasma density from RPC-Mutual Impedance Probe (MIP) and RPC-LAP. There is a good agreement between the modelled and RPC observed electron densities. The ionospheric model enables to distinguish the relative contributions of the different sources to the total cometary plasma. At high heliocentric distances, electron-impact ionisation becomes the dominant ionisation source and is enhanced over the winter hemisphere. As the solar activity has decreased since the beginning of the mission in 2014, the relative importance of photo-ionisation has decreased as well. However, at low heliocentric distances, photo-ionisation seems to be the most dominant ionising source, in particular through the perihelion period in summer 2015.

  10. PCB body burdens in US women of childbearing age 2001-2002: An evaluation of alternate summary metrics of NHANES data.

    PubMed

    Axelrad, Daniel A; Goodman, Stephanie; Woodruff, Tracey J

    2009-05-01

    An extensive body of epidemiologic data associates prenatal exposure to polychlorinated biphenyls (PCBs) with neurodevelopmental deficits and other childhood health effects. Neurological effects and other adverse health effects may also result from exposure during infancy, childhood, and adulthood. Although manufacture and use of PCBs were banned in the US in 1977, exposure to PCBs is a continuing concern due to the widespread distribution of these compounds in the environment and their persistence. The National Health and Nutrition Examination Survey provides PCB body burden measurements representative of the US population for the years 1999-2002. Interpretation of these data is challenging due to the large number of PCB congeners reported. We examined 6 PCB body burden metrics to identify an approach for summarizing the NHANES data and for characterizing changes over time in potential risks to children's health. We focused on women of childbearing age, defined here as 16-39 years, because in utero exposures have been associated with neurodevelopmental effects, and used only the 2001-2002 data because of higher detection rates. The 6 metrics, each consisting of different combinations of the 9 most frequently detected congeners, were as follows: total PCBs (all 9 congeners); highly chlorinated PCBs (2 congeners); dioxin-like PCBs (3 congeners, weighted by toxic equivalency factors); non-dioxin-like PCBs (6 congeners); a 4-congener metric (PCBs 118, 138, 153, and 180); and PCB-153 alone. The PCB metrics were generally highly correlated with each other. There was a strong association of PCB body burdens with age for all metrics. Median body burdens of Mexican American women were lower than those of non-Hispanic White and non-Hispanic Black women for 5 of the 6 metrics, and there were no significant differences in body burdens between the latter two groups. Body burdens of women with incomes above poverty level were greater than those for lower-income women at the

  11. Ionisation Equilibrium for the Non-Maxwellian Electron n-Distributions in Solar Flares: Updated Calculations

    NASA Astrophysics Data System (ADS)

    Dzifčáková, Elena; Dudík, Jaroslav

    2015-12-01

    We use the latest available atomic data to calculate the ionisation and recombination rates for the non-Maxwellian n-distributions, which were shown previously to provide a good fit to the enhanced intensities of dielectronic satellite lines during solar flares. The ionisation and recombination coefficients are subsequently used to derive the ionisation equilibrium. To do so, we consider odd values of n ranging from 1 to 19, i.e., from Maxwellian to strongly non-Maxwellian cases. These calculations involve all elements with proton number up to 30, i.e., H to Zn. The n-distributions modify both the ionisation and the recombination rates. The ionisation rates decrease more steeply at lower pseudo-temperatures, while the radiative recombination rate is reduced due to a lower number of low-energy electrons. The peaks of the dielectronic recombination rates become narrower. These changes are reflected in the ionisation equilibrium. Ion abundance peaks become narrower and can also be shifted, mostly towards higher temperatures. The He-like ions are an important exception, as they are formed in a larger temperature range than that for the Maxwellian distribution. The ions Si xiii - xiv used previously for the diagnostics of the n-distributions are affected only weakly, confirming the determination of n. The ionisation equilibria are available as the electronic supplementary material in a format compatible with the CHIANTI database.

  12. Ionisers in the management of bronchial asthma.

    PubMed Central

    Nogrady, S G; Furnass, S B

    1983-01-01

    Because of recent interest in the possible benefits to asthmatic patients of negative ion generators and the largely uncontrolled and inconclusive nature of earlier studies a double blind crossover study of this treatment was carried out in 20 subjects with stable asthma over six months. After an initial two week period without an ioniser, active or placebo ionisers were installed in subjects' bedrooms for two eight week periods separated by a four week "washout" period when no ioniser was present. The study was completed by a final four week period when no ioniser was present. Subjects were randomly allocated to receive an active or a placebo ioniser first. Subjects recorded their peak expiratory flow rate (PEFR) twice daily, completed a daily symptom score questionnaire, and noted any treatment they took on a diary card. Recordings were completed throughout the trial. Ion counts and dust concentrations were measured in subjects' bedrooms during the study. Mean ion counts rose considerably when ionisers were activated (p less than 0.001). There were no significant differences in PEFR, symptom score, or consumption of medication between the periods that active ionisers and either no ionisers or placebo ionisers were in operation. This study has failed to show a statistically significant benefit in asthmatic subjects from the use of negative ion generators. PMID:6364442

  13. Simulation studies on a prototype ionisation chamber for measurement of personal dose equivalent, Hp(10).

    PubMed

    Cardoso, J; Carvalho, A F; Oliveira, C

    2007-01-01

    A prototype ionisation chamber for direct measurement of the personal dose equivalent, Hp(10), similar to the one developed by the Physikalisch-Technische Bundesantalt (PTB), was designed and constructed by the Metrological Laboratory of Ionizing Radiation (LMRI) of Nuclear and Technological Institute (ITN). Tests already performed have shown that the behaviour of this chamber is very similar to the PTB chamber, mainly the energy dependence for the X-ray radiation qualities of the ISO 4037-1 narrow series N-30, N-40, N-60, N-80, N-100 and N-120 and also for gamma radiation of 137Cs and 60Co. However, the results obtained also show a dependence on the energy and angles of incident radiation and a low magnitude of the electrical response of the ionisation chamber. In order to optimise the performance of the chamber, the LMRI initiated numerical simulation of this ionisation chamber by Monte Carlo method using the MCNPX code.

  14. The effects of perchlorate, nitrate, and thiocyanate on free thyroxine for potentially sensitive subpopulations of the 2001-2002 and 2007-2008 National Health and Nutrition Examination Surveys.

    PubMed

    Suh, Mina; Abraham, Liz; Hixon, J Gregory; Proctor, Deborah M

    2014-11-01

    Among women with urinary iodine concentration <100 μg/l in the 2001-2002 National Health and Nutrition Examination Survey (NHANES), urinary perchlorate was associated with significant changes in thyroid stimulating hormone and total thyroxine (T4). Although perchlorate, nitrate, and thiocyanate all potentially act to inhibit iodide uptake, free T4 was not found to be associated with exposure to these chemicals in the same data. Fetuses of pregnant mothers with iodine deficiency are thought to be a sensitive subpopulation for perchlorate exposure, but the potential associations between free T4 and exposure to these chemicals among pregnant mothers in NHANES 2001-2002 and 2007-2008 have not been specifically evaluated to date. This study investigates the potential associations between urinary perchlorate, nitrate, and thiocyanate and serum free T4 in individuals with low urinary iodine levels and pregnant women. Multivariate regression models of free T4 were conducted and included urinary perchlorate, nitrate, thiocyanate, and covariates known to have an impact on the thyroid (anti-thyroid peroxidase (TPO) antibodies, age, race/ethnicity, body mass index, and hours of fasting). Meta-analyses were also conducted on non-pregnant and on pregnant women from the two survey cycles. Urinary nitrate was associated with serum free T4 in non-pregnant women of NHANES 2001-2002 who had urinary iodine ≥100 μg/l. In the meta-analysis, urinary perchlorate, nitrate, and thiocyanate were significant predictors of serum free T4 in non-pregnant women. No association was found in men and pregnant women. TPO antibodies were significant predictors of free T4 among non-pregnant women only when the models included urinary perchlorate, nitrate, or thiocyanate. Risk assessment for perchlorate exposure should consider co-exposure to nitrate and thiocyanate.

  15. Ionised outflows in z ~ 2.4 quasar host galaxies

    NASA Astrophysics Data System (ADS)

    Carniani, S.; Marconi, A.; Maiolino, R.; Balmaverde, B.; Brusa, M.; Cano-Díaz, M.; Cicone, C.; Comastri, A.; Cresci, G.; Fiore, F.; Feruglio, C.; La Franca, F.; Mainieri, V.; Mannucci, F.; Nagao, T.; Netzer, H.; Piconcelli, E.; Risaliti, G.; Schneider, R.; Shemmer, O.

    2015-08-01

    Aims: Outflows driven by active galactic nuclei (AGN) are invoked by galaxy evolutionary models to quench star formation and to explain the origin of the relations observed locally between super-massive black holes and their host galaxies. We here aim to detect extended ionised outflows in luminous quasars, where we expect the highest activity both in star formation and in black-hole accretion. Currently, there are only a few studies based on spatially resolved observations of outflows at high redshift, z > 2. Methods: We analysed a sample of six luminous (L > 1047 erg/s) quasars at z ~ 2.4, observed in H-band using the near-IR integral field spectrometer SINFONI at the VLT. We performed a kinematic analysis of the [Oiii] emission line at λ = 5007 Å. Results: We detect fast, spatially extended outflows in five out of six targets. [Oiii]λ5007 has a complex gas kinematic, with blue-shifted velocities of a few hundreds of km s-1 and line widths up to 1500 km s-1. Using the spectroastrometric method, we infer a size of the ionised outflows of up to ~2 kpc. The properties of the ionised outflows, mass outflow rate, momentum rate, and kinetic power, are correlated with the AGN luminosity. The increase in outflow rate with increasing AGN luminosity is consistent with the idea that a luminous AGN pushes away the surrounding gas through fast outflows that are driven by radiation pressure, which depends on the emitted luminosity. Conclusions: We derive mass outflow rates of about 6-700 M⊙ yr-1 for our sample, which are lower than those observed in molecular outflows. The physical properties of ionised outflows show dependences on AGN luminosity that are similar to those of molecular outflows, but indicate that the mass of ionised gas is lower than that of molecular outflows. Alternatively, this discrepancy between ionised and molecular outflows could be explained with different acceleration mechanisms. Based on Observations collected at the European Organisation for

  16. Reducing intraoperative duration and ionising radiation exposure during the insertion of distal locking screws of intramedullary nails: a small-scale study comparing the current fluoroscopic method against radiation-free, electromagnetic navigation.

    PubMed

    Grimwood, Darren; Harvey-Lloyd, Jane

    2016-12-01

    Intramedullary nailing is the standard surgical treatment for mid-diaphyseal fractures of long bones; however, it is also a high radiation dose procedure. Distal locking is regularly cited as a demanding element of the procedure, and there remains a reliance on X-ray fluoroscopy to locate the distal holes. A recently developed electromagnetic navigation (EMN) system allows radiation-free distal locking, with a virtual on-screen image. To compare operative duration, fluoroscopy time and radiation dose when using EMN over fluoroscopy, for the distal locking of intramedullary nails. Consecutive patients with mid-diaphyseal fractures of the tibia and femur, treatable with intramedullary nails, were prospectively enrolled during a 9-month period. The sample consisted of 29 individuals, 19 under fluoroscopic guidance and 10 utilising EMN. Participants were allocated depending on the type of intramedullary nail used and surgeon's preference. These were further divided into tibial and femoral subcategories, relative to the fracture site. EMN reduced fluoroscopy time by 49 (p = 0.038) and 28 s during tibial and femoral nailings, respectively. Radiation dose was reduced by 18 cGy/cm(2) (p = 0.046) during tibial and 181 cGy/cm(2) during femoral nailings when utilising EMN. Operative duration was 11 min slower during tibial nailings using EMN, but 38 min faster in respect of femoral nailings. This study has evidenced statistically significant reductions in both fluoroscopy time and radiation dose when using EMN for the distal locking of intramedullary nails. It is expected that overall operative duration would also decrease in line with similar studies, with increased usage and a larger sample.

  17. Serum ionised calcium concentration: measurement versus calculation.

    PubMed Central

    Conceicao, S C; Weightman, D; Smith, P A; Luno, J; Ward, M K; Kerr, D N

    1978-01-01

    Four hundred and eighteen measurements of serum ionised calcium, total calcium, and protein concentrations were made from 47 normal volunteers, 104 patients with chronic renal failure (33 being treated conservatively and 71 with regular haemodialysis), and 83 renal transplant recipients. The serum ionised calcium concentration was measured with an Orion SS-20 meter and calculated from the total serum calcium and protein concentrations by using three formulae and a nomogram. In the normal subjects and patients undergoing regular haemodialysis, whose serum calcium concentrations were in or near the normal range, three of the calculations gave results similar to those obtained by direct measurement. In patients with conservatively treated chronic renal failure and those who had received renal transplants, however, there was poor aggrement between the methods. When patients with hypercalcaemia and hypocalcaemia from all the groups were considered separately there was again poor agreement between calculated and measured concentrations of serum ionised calcium. Of the patients whose measured concentrations of serum ionised calcium were high, 69-76% were classified as normal by the four indirect methods. We conclude that calculation of the serum ionised calcium concentrations is not an adequate substitute for direct measurement. PMID:346162

  18. Tunnelling time in strong field ionisation

    NASA Astrophysics Data System (ADS)

    Landsman, Alexandra S.; Keller, Ursula

    2014-10-01

    We revisit the common approaches to tunnelling time in the context of attoclock experiments. These experiments measure tunnelling time using close-to-circularly polarised light of the infrared ultrashort laser pulse. We test the sensitivity of the attoclock measurements of tunnelling time to non-adiabatic effects, as described by a well-known theoretical model first developed by Perelomov, Popov, and Terent'ev. We find that in the case of ionisation of helium, both adiabatic and non-adiabatic theories give very similar predictions for ionisations times over a wide intensity range typical of ultrafast experiments.

  19. The ionisation energy of cyclopentadienone: a photoelectron-photoion coincidence study

    NASA Astrophysics Data System (ADS)

    Ormond, Thomas K.; Hemberger, Patrick; Troy, Tyler P.; Ahmed, Musahid; Stanton, John F.; Ellison, G. Barney

    2015-08-01

    Imaging photoelectron photoion coincidence (iPEPICO) spectra of cyclopentadienone (C5H4=O and C5D4=O) have been measured at the Swiss Light Source Synchrotron (Paul Scherrer Institute, Villigen, Switzerland) at the Vacuum Ultraviolet (VUV) Beamline. Complementary to the photoelectron spectra, photoionisation efficiency curves were measured with tunable VUV radiation at the Chemical Dynamics Beamline at the Advanced Light Source Synchrotron (Lawrence Berkeley National Laboratory, Berkeley, CA, USA). For both experiments, molecular beams diluted in argon and helium were generated from the vacuum flash pyrolysis of o-phenylene sulphite in a resistively heated microtubular SiC flow reactor. The Franck-Condon profiles and ionisation energies were calculated at the CCSD(T) level of theory, and are in excellent agreement with the observed iPEPICO spectra. The ionisation energies of both cyclopentadienone-d0, IE(C5H4=O), and cyclopentadienone-d4, IE(C5D4=O), were observed to be the same: 9.41 ± 0.01 eV. The mass-selected threshold photoelectron spectrum (ms-TPES) of cyclopentadienone reveals that the C=C stretch in the ground state of the cation is excited upon ionisation, supporting computational evidence that the ground state of the cation is ? 2A2, and is in agreement with previous studies. However, the previously reported ionisation potential has been improved considerably in this work. In addition, since o-benzoquinone (o-O=C6H4=O and o-O=C6D4=O) is also produced in this process, its ms-TPES has been recorded. From the iPEPICO and photoionisation efficiency spectra, we infer an adiabatic ionisation energy of IE(o-O=C6H4=O) = 9.3 ± 0.1 eV, but the rather structureless spectrum indicates a strong change in geometry upon ionisation making this value less reliable.

  20. Prevalence of 12-Month Alcohol Use, High-Risk Drinking, and DSM-IV Alcohol Use Disorder in the United States, 2001-2002 to 2012-2013: Results From the National Epidemiologic Survey on Alcohol and Related Conditions.

    PubMed

    Grant, Bridget F; Chou, S Patricia; Saha, Tulshi D; Pickering, Roger P; Kerridge, Bradley T; Ruan, W June; Huang, Boji; Jung, Jeesun; Zhang, Haitao; Fan, Amy; Hasin, Deborah S

    2017-09-01

    Lack of current and comprehensive trend data derived from a uniform, reliable, and valid source on alcohol use, high-risk drinking, and DSM-IV alcohol use disorder (AUD) represents a major gap in public health information. To present nationally representative data on changes in the prevalences of 12-month alcohol use, 12-month high-risk drinking, 12-month DSM-IV AUD, 12-month DSM-IV AUD among 12-month alcohol users, and 12-month DSM-IV AUD among 12-month high-risk drinkers between 2001-2002 and 2012-2013. The study data were derived from face-to-face interviews conducted in 2 nationally representative surveys of US adults: the National Epidemiologic Survey on Alcohol and Related Conditions, with data collected from April 2001 to June 2002, and the National Epidemiologic Survey on Alcohol and Related Conditions III, with data collected from April 2012 to June 2013. Data were analyzed in November and December 2016. Twelve-month alcohol use, high-risk drinking, and DSM-IV AUD. The study sample included 43 093 participants in the National Epidemiologic Survey on Alcohol and Related Conditions and 36 309 participants in the National Epidemiologic Survey on Alcohol and Related Conditions III. Between 2001-2002 and 2012-2013, 12-month alcohol use, high-risk drinking, and DSM-IV AUD increased by 11.2%, 29.9%, and 49.4%, respectively, with alcohol use increasing from 65.4% (95% CI, 64.3%-66.6%) to 72.7% (95% CI, 71.4%-73.9%), high-risk drinking increasing from 9.7% (95% CI, 9.3%-10.2%) to 12.6% (95% CI, 12.0%-13.2%), and DSM-IV AUD increasing from 8.5% (95% CI, 8.0%-8.9%) to 12.7% (95% CI, 12.1%-13.3%). With few exceptions, increases in alcohol use, high-risk drinking, and DSM-IV AUD between 2001-2002 and 2012-2013 were also statistically significant across sociodemographic subgroups. Increases in all of these outcomes were greatest among women, older adults, racial/ethnic minorities, and individuals with lower educational level and family income. Increases were also

  1. Changes in sexual behaviour and practice and HIV prevalence indicators among young people aged 15-24 years in Zambia: an in-depth analysis of the 2001-2002 and 2007 Zambia Demographic and Health Surveys.

    PubMed

    Kembo, Joshua

    2013-01-01

    HIV and AIDS still pose a major public health problem to most countries in sub-Saharan Africa, Zambia included. The objective of the paper is to determine changes in selected sexual behaviour and practice and HIV prevalence indicators between 2001-2002 and 2007. We used the Demographic and Health Survey Indicators Database for the computation of the selected indicators. We further used STATA 10.0 to compute significance tests to test for statistical difference in the indicators. The results indicate some changes in sexual behaviour, as indicated by an increase in abstinence, use of condoms and the decrease in multiple partnerships. The overall percentage of abstinence among never-married young men and women aged 15-24 years in Zambia increased significantly by 15.2% (p=.000) and 5.9% (p=.001) respectively, between 2001-2002 and 2007. A statistically significant increase of 6.6% (p=.029) was observed in the percentage of young women who reported having used a condom during the last time they had had premarital sex. A statistically significant decrease of 11.0% (p=.000) and 1.4% (p=.000) was observed among young men and women, respectively, who reported having multiple partners in the preceding 12 months. The factorial decomposition using multivariate analysis reveals that the indicators which contributed to the statistically significant 2.6% decline in HIV prevalence among young women aged 15-24 years in Zambia include proportion reporting condom use during premarital sex (+6.6%), abstinence (+5.9%), sex before age 15 (-4.5%), premarital sex (-2.6%), sex before age 18 (-2.4%) and proportion reporting multiple partnerships (-1.4%). Remarkable strides have been achieved towards promoting responsible sexual behaviour and practice among young people in Zambia. Further research focusing on factors that predispose young women in Zambia to higher risk of infection from HIV is required. The results from this paper should be useful in the design of programmes to control the

  2. The EDUTECH Report, 2001-2002.

    ERIC Educational Resources Information Center

    Warger, Thomas, Ed.

    2002-01-01

    This document consists of 12 issues of the "EDUTECH Report." The newsletter's purpose is to alert faculty and administrators to issues in educational technology. Each issue contains two feature articles, a page of news briefs, and a question and answer column. Issues also contain brief quotations on education technology topics. The…

  3. EDExpress Packaging Training, 2001-2002.

    ERIC Educational Resources Information Center

    Office of Student Financial Assistance (ED), Washington, DC.

    Packaging is the process of finding the best combination of aid to meet a student's financial need for college, given limited resources and the institutional constraints that vary from school to school. This guide to packaging under the EDExpress software system outlines three steps to packaging. The first is determining the student's need for…

  4. Deaf-Blind Perspectives, 2001-2002.

    ERIC Educational Resources Information Center

    Malloy, Peggy, Ed.

    2002-01-01

    Three issues of this newsletter on deaf-blind issues include announcements, reviews, news items, and the following articles: "'What's My Role?' A Comparison of the Responsibilities of Interpreters, Interveners, and Support Service Providers" (Susanne Morgan); "A Support Service Provider Program in Utah" (Cordie Weed);…

  5. Focus on Basics, 2001-2002.

    ERIC Educational Resources Information Center

    Garner, Barbara, Ed.

    2002-01-01

    This volume of newsletters focuses on connecting research and practice in adult literacy programs. Issue A of August 2001 includes: "Techniques for Teaching Beginning-Level Reading to Adults" (Ashley Hager); "Beginning ESOL Learners' Advice to Their Teachers" (MaryAnn Cunningham Florez); "The Neurobiology of Reading and…

  6. School-Age NOTES, 2001-2002.

    ERIC Educational Resources Information Center

    Scofield, Richard T., Ed.

    2002-01-01

    This document is comprised of the 12 monthly issues of a newsletter providing support and information for providers of child care for school-age children. The featured articles for each month are: (1) "Hispanic Heritage Month: Activity Ideas To Celebrate Hispanic Culture" (September); (2) "Borders: Finding Your Program's Niche"…

  7. Dengue fever, Hawaii, 2001-2002.

    PubMed

    Effler, Paul V; Pang, Lorrin; Kitsutani, Paul; Vorndam, Vance; Nakata, Michele; Ayers, Tracy; Elm, Joe; Tom, Tammy; Reiter, Paul; Rigau-Perez, José G; Hayes, John M; Mills, Kristin; Napier, Mike; Clark, Gary G; Gubler, Duane J

    2005-05-01

    Autochthonous dengue infections were last reported in Hawaii in 1944. In September 2001, the Hawaii Department of Health was notified of an unusual febrile illness in a resident with no travel history; dengue fever was confirmed. During the investigation, 1,644 persons with locally acquired denguelike illness were evaluated, and 122 (7%) laboratory-positive dengue infections were identified; dengue virus serotype 1 was isolated from 15 patients. No cases of dengue hemorrhagic fever or shock syndrome were reported. In 3 instances autochthonous infections were linked to a person who reported denguelike illness after travel to French Polynesia. Phylogenetic analyses showed the Hawaiian isolates were closely associated with contemporaneous isolates from Tahiti. Aedes albopictus was present in all communities surveyed on Oahu, Maui, Molokai, and Kauai; no Ae. aegypti were found. This outbreak underscores the importance of maintaining surveillance and control of potential disease vectors even in the absence of an imminent disease threat.

  8. PTAGIS Annual Progress Report, 2001-2002.

    SciTech Connect

    Pacific States Marine Fisheries Commission.

    2002-05-01

    This is the annual report for the PTAGIS project. February 28, 2002 marked the end of the 2001/02 PTAGIS fiscal year. All critical project activities progressed on schedule. However, a number of activities that have been traditionally performed by PTAGIS have been curtailed due to lack of resources. These reduced activities include production and distribution of the ''PTAGIS Newsletter'', development of a robust Web-based interface to PTAGIS data, curtailment efforts to upgrade critical database server hardware systems and processes and other activities. The main reasons for the lack of resources are: (1) In June, 2001, the region made a decision to expedite the installation of PIT tag detection at Bonneville and McNary dams. BPA issued contract 7422 to PSMFC to provide labor and material to install these systems. Nearly every PTAGIS resource was dedicated to this effort; (2) The Columbia Basin Fish and Wildlife Authority, Northwest Power Planning Council and Bonneville Power Administration have not solicited project proposals and budgets for over two years. Project requirements (represented in increasing scope, scale and complexity) have increased, but funding has not.

  9. Education Law Cases, 2001-2002.

    ERIC Educational Resources Information Center

    National School Boards Association, Alexandria, VA. Council of School Attorneys.

    This reference work is a supplement to the "Desk Reference on Significant Supreme Court Cases Affecting Public Education." It compiles summaries of selected education law cases from August 2001 through July 2002 and is intended as an overview of cases important to practitioners of school law. The text opens with a topical table of cases…

  10. English Leadership Quarterly, 2001-2002.

    ERIC Educational Resources Information Center

    Kiernan, Henry, Ed.; Wilcox, Bonita L., Ed.

    2002-01-01

    This 24th volume of "English Leadership Quarterly" contains articles on topics of interest to those in positions of leadership in departments (elementary, secondary, or college) where English is taught. Each issue focuses on a different theme. Articles in Volume 24 Number 1 focus on matters of thinking and are: "A New Way of…

  11. Breakfast in America, 2001-2002

    USDA-ARS?s Scientific Manuscript database

    The purpose of this study was to identify the demographic characteristics of American breakfast eaters, examine nutrient contributions of breakfast to the average U.S. diet, and identify top reported breakfast foods and beverages. Data were from individuals 2 years of age and older (n=9,033) from t...

  12. Degrees and Certificates Awarded, 2001-2002.

    ERIC Educational Resources Information Center

    Coperthwaite, Corby A.; Jones, Dennis

    This document reports on degrees and certificates awarded by the Connecticut community colleges during the 2001-02 academic year, using a set of eight categories. The colleges awarded 3,977 degrees and certificates in 2001-02. This represents a 1.3% increase over the previous year, and a 7.2% decrease since 1998. The colleges awarded 735…

  13. INTERACTION OF LASER RADIATION WITH MATTER. LASER PLASMA: Effect of pulsed laser target cleaning on ionisation and acceleration of ions in a plasma produced by a femtosecond laser pulse

    NASA Astrophysics Data System (ADS)

    Volkov, Roman V.; Vorobiev, A. A.; Gordienko, Vyacheslav M.; Dzhidzhoev, M. S.; Lachko, I. M.; Mar'in, B. V.; Savel'ev, Andrei B.; Uryupina, D. S.

    2005-10-01

    The impurity layer on the surface of a solid target is shown to exert a significant effect on the characteristics of the ion current of the laser plasma produced under the action of ultrahigh-intensity femtosecond radiation on the surface of this target. The application of pulsed laser cleaning gives rise to an additional high-energy component in the ion spectrum of the target material. It is shown that the ion current parameters of the laser plasma such as the average and highest ion charge, the highest ion energy of the target material, etc., can be controlled by varying the lead time of the cleaning laser radiation.

  14. Evaluation of a multiplex real-time reverse transcriptase PCR assay for detection and differentiation of influenza viruses A and B during the 2001-2002 influenza season in Israel.

    PubMed

    Hindiyeh, Musa; Levy, Virginia; Azar, Roberto; Varsano, Noemi; Regev, Liora; Shalev, Yael; Grossman, Zehava; Mendelson, Ella

    2005-02-01

    The ability to rapidly diagnose influenza virus infections is of the utmost importance in the evaluation of patients with upper respiratory tract infections. It is also important for the influenza surveillance activities performed by national influenza centers. In the present study we modified a multiplex real-time reverse transcriptase PCR (RT-PCR) assay (which uses TaqMan chemistry) and evaluated it for its ability to detect and concomitantly differentiate influenza viruses A and B in 370 patient samples collected during the 2001-2002 influenza season in Israel. The performance of the TaqMan assay was compared to those of a multiplex one-step RT-PCR with gel detection, a shell vial immunofluorescence assay, and virus isolation in tissue culture. The TaqMan assay had an excellent sensitivity for the detection of influenza viruses compared to that of tissue culture. The overall sensitivity and specificity of the TaqMan assay compared to the results of culture were 98.4 and 85.5%, respectively. The sensitivity and specificity of the TaqMan assay for the detection of influenza virus A alone were 100 and 91.1%, respectively. On the other hand, the sensitivity and specificity for the detection of influenza virus B alone were 95.7 and 98.7%, respectively. The rapid turnaround time for the performance of the TaqMan assay (4.5 h) and the relatively low direct cost encourage the routine use of this assay in place of tissue culture. We conclude that the multiplex TaqMan assay is highly suitable for the rapid diagnosis of influenza virus infections both in well-established molecular biology laboratories and in reference clinical laboratories.

  15. Addendum to: Evaluation of PCDD/F and dioxin-like PCB serum concentration data from the 2001-2002 National Health and Nutrition Examination Survey of the United States population.

    PubMed

    Scott, Laura L F; Unice, Kenneth M; Scott, Paul; Nguyen, Ly M; Haws, Laurie C; Harris, Mark; Paustenbach, Dennis

    2008-09-01

    In 2007, we published a paper in the Journal of Exposure Science and Environmental Epidemiology describing PCDD/F and dioxin-like PCB serum concentration data collected for the 2001-2002 National Health and Nutrition Examination Survey. Since publication of this paper, several of the 1998 World Health Organization Toxic Equivalency Factors (TEFs), which were used to calculate the summary statistics we presented, have been changed. In this addendum, we publish new reference statistics using the WHO(2006) TEFs in addition to assessing the effect of these new TEFs on total TEQ concentrations for the general US population. We also examined the effect of the limits of detection (LODs) on the calculated TEQ summary statistics for the top seven contributing congeners and completed a missing data analysis to determine whether our estimates were biased by excluding individuals without complete congener profiles. Similar to our previous results, 2, 3, 7, 8-TCDD; 1, 2, 3, 7, 8-PeCDD; 1, 2, 3, 6, 7, 8-HxCDD; 2, 3, 4, 7, 8-PeCDF; and PCB 126 contributed the most to total TEQ. However, both PCB 156 and 157 were no longer significant contributors, instead being displaced by 1, 2, 3, 4, 7, 8-HxCDF, and PCB 169. In general, the decrease in TEFs for the mono-ortho-substituted PCBs decreased their contribution to total TEQ appreciably, causing TEQ(17-9) to approximately equal TEQ(17-3). The effect of LODs for five of the top seven contributing congeners was negligible; however, the LODs for 2, 3, 7, 8-TCDD and 1, 2, 3, 7, 8-PeCDD were noticeably higher and may impact TEQ estimates primarily for individuals aged 20-29 years. Results from the missing data analysis provide compelling evidence that the summary statistics we reported previously, as well as those described here, were not greatly influenced due to censoring data.

  16. The nature of the ionised nebula surrounding the red supergiant W26

    NASA Astrophysics Data System (ADS)

    Wesson, Roger

    2015-08-01

    The red supergiant W26 in the massive star cluster Westerlund 1 is surrounded by a compact ionised nebula. This is unique among RSGs, and the excitation mechanism of the nebula is not yet known - it may be ionised by an unseen compact companion, or by a nearby blue supergiant. We present new observations of the nebula: high resolution spatially resolved spectra taken with FLAMES at the VLT show that the nebula is a ring, with velocities consistent with that expected for red supergiant ejecta, and ruling out the possibility of a Luminous Blue Variable-type eruption preceding the RSG phase as the origin of the nebula. A triangular patch of nebulosity outside the ring appears to be associated with W26, and may be material stripped from the expanding ring by the cumulative cluster wind and radiation field.

  17. Students' Conceptions of Ionisation Energy: A Cross-Cultural Study

    ERIC Educational Resources Information Center

    Tan, Kim Chwee Daniel; Taber, Keith S.; Liu, Xiufeng; Coll, Richard K.; Lorenzo, Mercedes; Li, Jia; Goh, Ngoh Khang; Chia, Lian Sai

    2008-01-01

    Previous studies have indicated that A-level students in the UK and Singapore have difficulty learning the topic of ionisation energy. A two-tier multiple-choice instrument developed in Singapore in an earlier study, the Ionisation Energy Diagnostic Instrument, was administered to A-level students in the UK, advanced placement high school students…

  18. Students' Conceptions of Ionisation Energy: A Cross-Cultural Study

    ERIC Educational Resources Information Center

    Tan, Kim Chwee Daniel; Taber, Keith S.; Liu, Xiufeng; Coll, Richard K.; Lorenzo, Mercedes; Li, Jia; Goh, Ngoh Khang; Chia, Lian Sai

    2008-01-01

    Previous studies have indicated that A-level students in the UK and Singapore have difficulty learning the topic of ionisation energy. A two-tier multiple-choice instrument developed in Singapore in an earlier study, the Ionisation Energy Diagnostic Instrument, was administered to A-level students in the UK, advanced placement high school students…

  19. Determination of structure parameters in molecular tunnelling ionisation model

    NASA Astrophysics Data System (ADS)

    Wang, Jun-Ping; Zhao, Song-Feng; Zhang, Cai-Rong; Li, Wei; Zhou, Xiao-Xin

    2014-04-01

    We extracted the accurate structure parameters in a molecular tunnelling ionisation model (the so-called MO-ADK model) for 23 selected linear molecules including some inner orbitals. The molecular wave functions with the correct asymptotic behaviour are obtained by solving the time-independent Schrödinger equation with B-spline functions and molecular potentials numerically constructed using the modified Leeuwen-Baerends (LBα) model. We show that the orientation-dependent ionisation rate reflects the shape of the ionising orbitals in general. The influences of the Stark shifts of the energy levels on the orientation-dependent ionisation rates of the polar molecules are studied. We also examine the angle-dependent ionisation rates (or probabilities) based on the MO-ADK model by comparing with the molecular strong-field approximation calculations and with recent experimental measurements.

  20. Changes in time-use and drug use by young adults in poor neighbourhoods of Greater Buenos Aires, Argentina, after the political transitions of 2001-2002: Results of a survey

    PubMed Central

    2011-01-01

    Background In some countries, "Big Events" like crises and transitions have been followed by large increases in drug use, drug injection and HIV/AIDS. Argentina experienced an economic crisis and political transition in 2001/2002 that affected how people use their time. This paper studies how time use changes between years 2001 and 2004, subsequent to these events, were associated with drug consumption in poor neighbourhoods of Greater Buenos Aires. Methods In 2003-2004, 68 current injecting drug users (IDUs) and 235 young non-IDUs, aged 21-35, who lived in impoverished drug-impacted neighbourhoods in Greater Buenos Aires, were asked about time use then and in 2001. Data on weekly hours spent working or looking for work, doing housework/childcare, consuming drugs, being with friends, and hanging out in the neighbourhood, were studied in relation to time spent using drugs. Field observations and focus groups were also conducted. Results After 2001, among both IDUs and non-IDUs, mean weekly time spent working declined significantly (especially among IDUs); time spent looking for work increased, and time spent with friends and hanging out in the neighbourhood decreased. We found no increase in injecting or non-injecting drug consumption after 2001. Subjects most affected by the way the crises led to decreased work time and/or to increased time looking for work--and by the associated increase in time spent in one's neighbourhood--were most likely to increase their time using drugs. Conclusions Time use methods are useful to study changes in drug use and their relationships to every day life activities. In these previously-drug-impacted neighbourhoods, the Argentinean crisis did not lead to an increase in drug use, which somewhat contradicts our initial expectations. Nevertheless, those for whom the crises led to decreased work time, increased time looking for work, and increased time spent in indoor or outdoor neighbourhood environments, were likely to spend more time

  1. Dosimetric aspects of film/screen mammography: in-phantom dosimetry with thimble-type ionisation chambers.

    PubMed

    Zoetelief, J; de Wit, N J; Broerse, J J

    1989-09-01

    The characteristics of 0.6 cm3 thimble-type Baldwin-Farmer (BF 2571) ionisation chambers for absorbed dose determinations in-phantom at mammography installations are investigated. The most important aspects for in-phantom dosimetry in mammography concern the conversion from air kerma to absorbed dose in mammary gland tissue, the energy dependence of the sensitivity of the ionisation chamber and the displacement correction factor for measurements in-phantom. Due to the considerable uncertainties in the elemental composition of the mammary glands the conversion from air kerma to absorbed dose in the mammary gland tissue has an uncertainty of the order of +/- 20%. The air kerma calibration factor of the BF-ionisation chamber is about 10% larger at mammography radiation qualities than at 300 kV x-rays or 137Cs gamma rays. For depths in excess of about 15 mm a displacement correction factor of 0.69 +/- 0.06 is derived for measurements with the BF 2571 chamber inside polymethylmethacrylate (PMMA) phantoms irradiated with 30 kV x-rays (first HVL:0.29 mm Al). The previously reported discrepancy between dose measurements with TLD and ionisation chambers at the entrance surface of a phantom for mammography radiation qualities is resolved and could be attributed to attenuation in the TLD encapsulation material.

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

    NASA Astrophysics Data System (ADS)

    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.

  3. The Indigenous World, 2001-2002 = El Mundo Indigena, 2001-2002.

    ERIC Educational Resources Information Center

    Vinding, Diana, Ed.; Wessendorff, Kathrin, Ed.; Parellada, Alejandro, Ed.; Erni, Christian, Ed.; Jensen, Marianne, Ed.; Garcia-Alix, Lola, Ed.

    This document contains the English and Spanish texts of an annual publication which examines political, social, environmental, and educational issues concerning indigenous peoples around the world in 2001-02. Part 1 describes current situations and events in 11 world regions: the Arctic; North America; Mexico and Central America; South America;…

  4. Ayuda economica: Guia para estudiantes, 2001-2002 (Financial Aid: Student Guide, 2001-2002).

    ERIC Educational Resources Information Center

    Office of Student Financial Assistance (ED), Washington, DC.

    This guide, written in Spanish, describes federal student aid programs for postsecondary education and how to apply for them. It begins by outlining sources for learning about student aid, such as school financial aid administrators, state higher education agencies, foundations, organizations related to particular fields of interest and toll-free…

  5. The Indigenous World, 2001-2002 = El Mundo Indigena, 2001-2002.

    ERIC Educational Resources Information Center

    Vinding, Diana, Ed.; Wessendorff, Kathrin, Ed.; Parellada, Alejandro, Ed.; Erni, Christian, Ed.; Jensen, Marianne, Ed.; Garcia-Alix, Lola, Ed.

    This document contains the English and Spanish texts of an annual publication which examines political, social, environmental, and educational issues concerning indigenous peoples around the world in 2001-02. Part 1 describes current situations and events in 11 world regions: the Arctic; North America; Mexico and Central America; South America;…

  6. INTERACTION OF LASER RADIATION WITH MATTER. LASER PLASMA: On the bifurcation of the circular polarisation of the fifth and seventh pump-field harmonics generated in the plasma produced by the ionisation of a gas of excited hydrogen-like atoms

    NASA Astrophysics Data System (ADS)

    Silin, Viktor P.; Silin, Pavel V.

    2006-05-01

    Within the framework of the Bethe ionisation model we considered theoretically the dependences of the degree of circular polarisation of the fifth and seventh pump-field harmonics, which are generated due to bremsstrahlung, on the electric intensity of the pump field, the degree of its circular polarisation, and the principal quantum number of the excited states of hydrogen-like atoms of a gas ionised by the pump field. A bifurcation of the circular polarisation of these harmonics was discovered, which confirms our previous hypothesis that this effect is common for harmonics generated due to the bremsstrahlung in the pump field when the plasma electrons oscillate in this field. We determined how the relationships under consideration are scaled with VEn/VZ, the product of electron oscillation velocity and the principal quantum number of the excited electron divided by the Coulomb velocity.

  7. Cosmic-ray ionisation of dense molecular clouds

    NASA Astrophysics Data System (ADS)

    Vaupre, Solenn

    2015-07-01

    Cosmic rays (CR) are of tremendous importance in the dynamical and chemical evolution of interstellar molecular clouds, where stars and planets form. CRs are likely accelerated in the shells of supernova remnants (SNR), thus molecular clouds nearby can be irradiated by intense fluxes of CRs. CR protons have two major effects on dense molecular clouds: 1) when they encounter the dense medium, high-energy protons (>280 MeV) create pions that decay into gamma-rays. This process makes SNR-molecular cloud associations intense GeV and/or TeV sources whose spectra mimic the CR spectrum. 2) at lower energies, CRs penetrate the cloud and ionise the gas, leading to the formation of molecular species characteristic of the presence of CRs, called tracers of the ionisation. Studying these tracers gives information on low-energy CRs that are unaccessible to any other observations. I studied the CR ionisation of molecular clouds next to three SNRs: W28, W51C and W44. These SNRs are known to be interacting with the nearby clouds, from the presence of shocked gas, OH masers and pion-decay induced gamma-ray emission. My work includes millimeter observations and chemical modeling of tracers of the ionisation in these dense molecular clouds. In these three regions, we determined an enhanced CR ionisation rate, supporting the hypothesis of an origin of the CRs in the SNR nearby. The evolution of the CR ionisation rate with the distance to the SNR brings valuable constraints on the propagation properties of low-energy CRs. The method used relies on observations of the molecular ions HCO+ and DCO+, which shows crucial limitations at high ionisation. Therefore, I investigated, both through modeling and observations, the chemical abundances of several other species to try and identity alternative tracers of the ionisation. In particular, in the W44 region, observations of N2H+ bring additional constraints on the physical conditions, volatile abundances in the cloud, and the ionisation

  8. Skin dose measurements using radiochromic films, TLDS and ionisation chamber and comparison with Monte Carlo simulation.

    PubMed

    Alashrah, Saleh; Kandaiya, Sivamany; Maalej, Nabil; El-Taher, A

    2014-12-01

    Estimation of the surface dose is very important for patients undergoing radiation therapy. The purpose of this study is to investigate the dose at the surface of a water phantom at a depth of 0.007 cm as recommended by the International Commission on Radiological Protection and International Commission on Radiation Units and Measurement with radiochromic films (RFs), thermoluminescent dosemeters and an ionisation chamber in a 6-MV photon beam. The results were compared with the theoretical calculation using Monte Carlo (MC) simulation software (MCNP5, BEAMnrc and DOSXYZnrc). The RF was calibrated by placing the films at a depth of maximum dose (d(max)) in a solid water phantom and exposing it to doses from 0 to 500 cGy. The films were scanned using a transmission high-resolution HP scanner. The optical density of the film was obtained from the red component of the RGB images using ImageJ software. The per cent surface dose (PSD) and percentage depth dose (PDD) curve were obtained by placing film pieces at the surface and at different depths in the solid water phantom. TLDs were placed at a depth of 10 cm in a solid water phantom for calibration. Then the TLDs were placed at different depths in the water phantom and were exposed to obtain the PDD. The obtained PSD and PDD values were compared with those obtained using a cylindrical ionisation chamber. The PSD was also determined using Monte Carlo simulation of a LINAC 6-MV photon beam. The extrapolation method was used to determine the PSD for all measurements. The PSD was 15.0±3.6% for RF. The TLD measurement of the PSD was 16.0±5.0%. The (0.6 cm(3)) cylindrical ionisation chamber measurement of the PSD was 50.0±3.0%. The theoretical calculation using MCNP5 and DOSXYZnrc yielded a PSD of 15.0±2.0% and 15.7±2.2%. In this study, good agreement between PSD measurements was observed using RF and TLDs with the Monte Carlo calculation. However, the cylindrical chamber measurement yielded an overestimate of the PSD

  9. Ionisation and the Formation of Low-Mass Protostars

    NASA Astrophysics Data System (ADS)

    Wurster, James; Bate, M. R.; Price, D. J.

    2017-06-01

    Molecular clouds are known to have strong magnetic fields and low ionisation rates. Numerical simulations performed with these more realistic conditions yield results closer to those observed, and furthermore, suggest additional observational signatures not yet explored. I will discuss my simulations of the formation of a single protostar starting from one solar mass of gas; the models include a self-consistent treatment of all three non-ideal MHD processes. My focus will be on how the ionisation parameters and non-ideal MHD processes affect the formation of the protostar and its environment.

  10. [Bipolar ionisation of indoor air through ion generators mountable into inflow ventilation and conditioning].

    PubMed

    Dudarev, A A; Spichkin, G L; Denisikhina, D M; Burtsev, S I

    2010-01-01

    Experimental studies and digital modelling of artificial indoor air ionisation through bipolar ionisers mountable into inflow ventilation and conditioning proved possible creation of continuous even bipolar ion background in indoor air, similar to the natural one.

  11. Nonintrusive measurement of ionisation in vegetation fire plasma

    NASA Astrophysics Data System (ADS)

    Mphale, K. M.; Heron, M.

    2008-02-01

    Vegetation fires are slightly ionised gaseous medium. Omnipresent alkali metal species in plant's organic structure are the main source of thermally produced electrons in the fires. In the flames, electron-neutral particle collisions dominate other modes of particle interaction. The collision regime absorbs some of the incident energy when the fire is illuminated with electromagnetic waves. The rate of electromagnetic wave absorption in the vegetation fires has implications on the safety of fire-fighters. During wildfire suppression, radio communication blackout at vhf/uhf has been experienced. This may be partly due to thermal ionisation in the fire. In the experiment, the extent of ionisation in vegetation fires is measured using a 2-port vector network analyser. X-band microwaves are caused to propagate combustion zones of eucalyptus bark and guinea grass fires with maximum temperatures of 1114 and 1054 K respectively. Alkali content in the vegetation fuel was different. Measurements show maximum ionisation in flames produced from guinea grass, which had almost twice much potassium as that of eucalyptus bark, to be 2.63×1016 m-3 while that produced in eucalyptus bark flame was 1.46×1016 m-3.

  12. Ionisation chamber containing boron as a neutron detector in medical accelerator fields.

    PubMed

    Zielczynski, M; Gryzinski, M A; Golnik, N; Tulik, P

    2007-01-01

    A combination of the recombination principle of H(10) measurements with the use of the ionisation chambers containing boron has been presented, in order to increase the relative sensitivity of the chamber to neutrons by a factor close to the radiation quality factor of photoneutrons. Three types of the chambers were investigated. Two of them were filled with BF(3) and the third one contained electrodes covered with B(4)C. All the chambers were placed in paraffin moderators. The response of the chambers was investigated, depending on gas pressure and polarising voltage. The results showed that it was possible to obtain nearly the same response of the chamber to H(10) for photons and neutrons in a restricted energy range; however, further investigations are needed to make an optimum design.

  13. Ionisation of a quantum dot by electric fields

    SciTech Connect

    Eminov, P A; Gordeeva, S V

    2012-08-31

    We have derived analytical formulas for differential and total ionisation probabilities of a two-dimensional quantum dot by a constant electric field. In the adiabatic approximation, we have calculated the probability of this process in the field of a plane electromagnetic wave and in a superposition of constant and alternating electric fields. The imaginary-time method is used to obtain the momentum distribution of the ionisation probability of a bound system by an intense field generated by a superposition of parallel constant and alternating electric fields. The total probability of the process per unit time is calculated with exponential accuracy. The dependence of the results obtained on the characteristic parameters of the problem is investigated. (laser applications and other topics in quantum electronics)

  14. THE INFLUENCE OF SALTS UPON THE IONISATION OF EGG ALBUMIN

    PubMed Central

    Sørensen, S. P. L.; Linderstrøm-Lang, K.; Lund, Ellen

    1927-01-01

    Introduction. A description is given of the principle followed in the experimental determination of the ionisation of egg albumin, its capacity to combine with acids and bases. Egg albumin is regarded as an ampholyte, and in accordance with J. N. Brønsted's definition of acids and bases, ampholytes are considered as substances capable of both taking up and giving off hydrogen ions. The theoretical treatment of the capacity of ampholytes to combine with acids (and bases) has been carried out on this basis. Section A. Several experimental series are noted, comprising the determination of the activity coefficient of the hydrogen ion (fH) in ammonium chloride solutions of different concentration. Section B. The general method of experimental determination of the ionisation (capacity to combine with adds and bases) of egg albumin in ammonium chloride and potassium chloride solutions is briefly described, and the results of the experiments are compared. Section C. 1). In a brief theoretical survey we have suggested that distinction should be made between isoelectric and isoionic reaction of an ampholyte, the former defined as the hydrogen ion activity (value of paH) at which the mean valency of the ampholyte is 0, the latter as the hydrogen ion activity at which the quantity of acid or base combined with the ampholyte is 0; or, as we prefer to express it, the hydrogen ion activity at which the specific hydrogen ionisation of the ampholyte is 0. If the ampholyte does not combine with other ions than the hydrogen ion, then isoelectric and isoionic reaction coincide. Isoionic reaction is determined by acid-combining experiments. The principle of this determination is briefly described. A theoretical investigation of the alteration with salt concentration of both isoelectric (isoionic) reaction and the shape and direction of the ionisation curves is made, with regard to ampholytes capable only of combining with hydrogen ions, on the basis of the Debye-Hückel formulæ and

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

    PubMed

    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

  16. High ionisation absorption in low mass X-ray binaries

    NASA Astrophysics Data System (ADS)

    Ponti, G.; Bianchi, S.; Muñoz-Darias, T.; De, K.; Fender, R.; Merloni, A.

    2016-05-01

    The advent of the new generation of X-ray telescopes yielded a significant step forward in our understanding of ionised absorption generated in the accretion discs of X-ray binaries. It has become evident that these relatively weak and narrow absorption features, sporadically present in the X-ray spectra of some systems, are actually the signature of equatorial outflows, which might carry away more matter than that being accreted. Therefore, they play a major role in the accretion phenomenon. These outflows (or ionised atmospheres) are ubiquitous during the softer states but absent during the power-law dominated, hard states, suggesting a strong link with the state of the inner accretion disc, presence of the radio-jet and the properties of the central source. Here, we discuss the current understanding of this field.

  17. Fully kinetic simulations of magnetic reconnection in partially ionised gases

    NASA Astrophysics Data System (ADS)

    Innocenti, M. E.; Jiang, W.; Lapenta, G.; Markidis, S.

    2016-12-01

    Magnetic reconnection has been explored for decades as a way to convert magnetic energy into kinetic energy and heat and to accelerate particles in environments as different as the solar surface, planetary magnetospheres, the solar wind, accretion disks, laboratory plasmas. When studying reconnection via simulations, it is usually assumed that the plasma is fully ionised, as it is indeed the case in many of the above-mentioned cases. There are, however, exceptions, the most notable being the lower solar atmosphere. Small ionisation fractions are registered also in the warm neutral interstellar medium, in dense interstellar clouds, in protostellar and protoplanetary accreditation disks, in tokamak edge plasmas and in ad-hoc laboratory experiments [1]. We study here how magnetic reconnection is modified by the presence of a neutral background, i.e. when the majority of the gas is not ionised. The ionised plasma is simulated with the fully kinetic Particle-In-Cell (PIC) code iPic3D [2]. Collisions with the neutral background are introduced via a Monte Carlo plug-in. The standard Monte Carlo procedure [3] is employed to account for elastic, excitation and ionization electron-neutral collisions, as well as for elastic scattering and charge exchange ion-neutral collisions. Collisions with the background introduce resistivity in an otherwise collisionless plasma and modifications of the particle distribution functions: particles (and ions at a faster rate) tend to thermalise to the background. To pinpoint the consequences of this, we compare reconnection simulations with and without background. References [1] E E Lawrence et al. Physical review letters, 110(1):015001, 2013. [2] S Markidis et al. Mathematics and Computers in Simulation, 80(7):1509-1519, 2010. [3] K Nanbu. IEEE Transactions on plasma science, 28(3):971-990, 2000.

  18. Electrospray Ionisation Mass Spectrometry: Principles and Clinical Applications

    PubMed Central

    Ho, CS; Lam, CWK; Chan, MHM; Cheung, RCK; Law, LK; Lit, LCW; Ng, KF; Suen, MWM; Tai, HL

    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. PMID:18568044

  19. Erich Regener and the ionisation maximum of the atmosphere

    NASA Astrophysics Data System (ADS)

    Carlson, P.; Watson, A. A.

    2014-12-01

    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. Along with one of his students, Georg Pfotzer, he discovered 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 his links with Rutherford's group in Cambridge, is discussed in an appendix. Regener was nominated for the Nobel Prize in Physics by Schrödinger in 1938. He died in 1955 at the age of 73.

  20. Resonance ionisation mass spectrometry of krypton and its applications in planetary science

    NASA Astrophysics Data System (ADS)

    Strashnov, I.; Gilmour, J. D.

    2014-06-01

    A new resonance ionisation time-of-flight mass spectrometer for determining krypton isotope ratios in extraterrestrial samples is presented. Laser heating is used to extract gas from mg-size samples. A cryogenic sample concentrator is employed. Atoms continuously condense on a 75 K stainless steel substrate at the back plate of a Wiley-McLaren laser ion source from where they are desorbed by a pulsed 1064 nm laser and resonantly ionized in the plume. A three-colour (116.5 nm, 558.1 nm and 1064 nm) excitation scheme is used. Tuneable coherent Vacuum Ultraviolet (vuv) radiation near 116.5 nm is generated by four-wave sum frequency mixing of 252.5 nm and 1507 nm pulsed dye laser beams in a binary mixture of negatively and positively dispersive gases (Xe and Ar). Isotope effects have been observed that reduce the reproducibility of isotope ratio measurements between odd-mass, non-zero nuclear spin isotopes and even-mass, zero nuclear spin isotopes. This can be minimised and stabilised by controlling the laser fluences, experimental geometry, and the population of the magnetic sub-levels of the excited atomic states used in the ionisation process. Once stability is achieved, sample-standard bracketing (during which the known isotope ratios of a standard are determined before and after the measurements of the sample under the same conditions) allows precision and reproducibility of 1 % for the major isotope ratios to be achieved in samples krypton atoms. Detection limits of atoms/isotope have been demonstrated, ratios of Kr in meteorites have been made with 5-10 % precision. Applications of the instrument in various areas of planetary science are also discussed.

  1. Threshold law for positron-atom impact ionisation

    NASA Technical Reports Server (NTRS)

    Temkin, A.

    1982-01-01

    The threshold law for ionisation of atoms by positron impact is adduced in analogy with our approach to the electron-atom ionization. It is concluded the Coulomb-dipole region of the potential gives the essential part of the interaction in both cases and leads to the same kind of result: a modulated linear law. An additional process which enters positron ionization is positronium formation in the continuum, but that will not dominate the threshold yield. The result is in sharp contrast to the positron threshold law as recently derived by Klar on the basis of a Wannier-type analysis.

  2. The influence of stopping power on the ionisation quench factor.

    PubMed

    García, G; Grau, Malonda A

    2002-01-01

    Stopping power values for high energies have been computed applying the first Born approximation and the Bethe formula. However, this approximation tends to overestimate these cross sections at low energies, reaching discrepancies on the order of 50% at energies below 1 keV for most of the molecular targets of interest. In this paper we propose a method to obtain accurate low energy stopping powers of electrons by combining total cross section measurements with a theoretical treatment of the elastic process. We determine the optimum value of the kB parameter of ionisation quenching for the stopping power obtained in this paper.

  3. Intercomparison of ionisation chamber measurements from (125)I seeds.

    PubMed

    Davies, J B; Enari, K F; Baldock, C

    2007-05-01

    The reference air kerma rates of a set of individual (125)I seeds were calculated from current measurements of a calibrated re-entrant ionisation chamber. Single seeds were distributed to seven Australian brachytherapy centres for the same measurement with the user's instrumentation. Results are expressed as the ratio of the reference air kerma rate measured by the Australian Nuclear Science & Technology Organisation (ANSTO) to the reference air kerma rate measured at the centre. The intercomparison ratios of all participants were within +/-5% of unity.

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

    NASA Astrophysics Data System (ADS)

    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.

  5. The properties of the extended warm ionised gas around low-redshift QSOs and the lack of extended high-velocity outflows

    NASA Astrophysics Data System (ADS)

    Husemann, B.; Wisotzki, L.; Sánchez, S. F.; Jahnke, K.

    2013-01-01

    We present a detailed analysis of a large sample of 31 low-redshift, mostly radio-quiet type 1 quasi-stellar objects (QSOs) observed with integral field spectroscopy to study their extended emission-line regions (EELRs). We focus on the ionisation state of the gas, size and luminosity of extended narrow line regions (ENLRs), which corresponds to those parts of the EELR dominated by ionisation from the QSO, as well as the kinematics of the ionised gas. We detect EELRs around 19 of our 31 QSOs (61%) after deblending the unresolved QSO emission and the extended host galaxy light in the integral field data with a new dedicated algorithm. Based on standard emission-line diagnostics we identify 13 EELRs to be entirely ionised by the QSO radiation, 3 EELRs are composed of H ii regions and 3 EELRs display signatures of both ionisation mechanisms at different locations. The typical size of the ENLR is ~10 kpc at a median nuclear [O iii] luminosity of log (L([O iii])/ [ergs-1]) = 42.7 ± 0.15. We show that the ENLR sizes are least a factor of ~2 larger than determined with the Hubble Space Telescope, but are consistent with those of recently reported type 2 QSOs at matching [O iii] luminosities. The ENLR of type 1 and type 2 QSOs therefore appear to follow the same size-luminosity relation. Furthermore, we show for the first time that the ENLR size is much better correlated with the QSO continuum luminosity than with the total/nuclear [O iii] luminosity. We show that ENLR luminosity and radio luminosity are correlated, and argue that radio jets even in radio-quiet QSOs are important for shaping the properties of the ENLR. Strikingly, the kinematics of the ionised gas is quiescent and likely gravitationally driven in the majority of cases and we find only 3 objects with radial gas velocities exceeding >400 km s-1 in specific regions of the EELR that can be associate with radio jets. In general, these are significantly lower outflow velocities and detection rates compared to

  6. Partial ionisation cross-sections of 2-propanol and ethanal

    NASA Astrophysics Data System (ADS)

    Vacher, J. R.; Jorand, F.; Blin-Simiand, N.; Pasquiers, S.

    2006-04-01

    Electron impact ionisation of 2-propanol and ethanal is studied using mass spectrometry. Cross-sections of the formation of molecular ions and ionic fragments are measured between 14 and 86 eV. Free energy changes are evaluated using ab initio calculations. For 2-propanol, two ions, identified as CH 3CHOH + (45 amu) and CH3CHCH3+ (43 amu), contribute more than 75% to the total cross-section over the whole range of electron energies and are produced by simple bond cleavage in the molecular ion. Both processes occur spontaneously, leaving the molecular ion as a minority species. For ethanal, two ions, identified as HCO + (29 amu) and CH 3CO + (43 amu), and the molecular ion (44 amu) contribute more than 80% to the total cross-section. The ions of 29 and 43 amu result from a simple bond cleavage in the molecular ion. These sprocesses are not spontaneous and the contribution of the molecular ion becomes predominant at 15 eV and is therefore significant over the whole range of ionisation energies.

  7. On-line reaction monitoring by extractive electrospray ionisation.

    PubMed

    McCullough, Bryan J; Bristow, Tony; O'Connor, Gavin; Hopley, Chris

    2011-05-30

    The design and development of a novel extractive electrospray ionisation (EESI) device for on-line reaction monitoring is described. The EESI apparatus uses a secondary, grounded nebuliser to produce an analyte aerosol and a Venturi pump is then used to transfer a sample of the aerosol to an electrospray source where it is ionised. The EESI apparatus was then tested with a variety of small, organic molecules to assess sensitivity, linearity and dynamic range. The performance of the technique will depend on the mass spectrometer used for the experiments; in the configurations used here it has a usable dynamic range of around 3.5 orders of magnitude with a linear range of around 2.5 orders of magnitude and is capable of analysing species present down to low µg/mL with signal-to-noise ratio greater than 2.5. The use of EESI for reaction monitoring was validated using a series of mock reaction mixtures and then used to monitor the base hydrolysis of ethyl salicylate to salicylic acid. Copyright © 2011 John Wiley & Sons, Ltd.

  8. Kr-81m calibration factor for the npl ionisation chamber.

    PubMed

    Johansson, Lena; Stroak, Andrew

    2006-01-01

    A general method has been developed for the measurement of the activity concentration of 81mKr gas. Due to its short half-life, 13.1s, this gas has to be eluted from a 81Rb/81mKr generator. The 81Rb parent has a half-life of about 4.6 h. The calibration was done in two steps: firstly, a gamma-ray spectrometer was calibrated using 51Cr and 139Ce sources, nuclides with gamma-ray energies bracketing that of 81mKr (190.5 keV). The measurement geometry was equivalent to that of the 81mKr measurement; the sources were inserted into two collimated PTFE tubes in front of the gamma-ray detector. Secondly, a calibration factor for the NPL radionuclide calibrator was determined with a specially designed ionisation chamber insert. The 81mKr gas passed in front of the gamma-ray detector in PTFE tubing before and after entering the ionisation chamber. The calibration factor for 81mKr in the radionuclide calibrator with this geometry was independent of the gas flow rate within determined limits. The analytical calculations of the activity determination, uncertainties and measurement criteria are discussed.

  9. A low background ionisation chamber for alpha-spectroscopy

    NASA Astrophysics Data System (ADS)

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

    2017-09-01

    The goal of designing a low background ionisation chamber is to measure long lived α-decay half-lives which might interfere with rare event searches. Such decays play a part in many fields in nuclear physics and are difficult to measure. A lot of Geiger-Nutall studies also depend on them. Among others the research is specifically aimed at the precision measurements of α emitters mainly within the Lanthanide region. The excellent energy resolution would also allow to search for excited states in α-decays. To achieve this goal a gridded ionisation chamber was constructed using the Frisch-Grid design. A background rate of only 10.9(6) counts per day has been achieved in the energy region of 1 MeV to 9 MeV and improvements are possible. This low background rate and size of the chamber allows precision measurements of long living alpha decays with half-lives in the region of 1 × 1015 years.

  10. Event-based versus process-based informed consent to address scientific evidence and uncertainties in ionising medical imaging.

    PubMed

    Recchia, Virginia; Dodaro, Antonio; Braga, Larissa

    2013-10-01

    Inappropriate ionising medical imaging has been escalating in the last decades. This trend leads to potential damage to health and has been associated to bioethical and legal issues of patient autonomy. While the doctrine underlines the importance of using informed consent to improve patient autonomy and physician-patient communication, some researchers have argued that it often falls short of this aim. There are basically two different informed consent practices. The first - the so-called "event-based model" - regards informed consent as a passive signature of a standard unreadable template, performed only once in each medical pathway. The second - the so-called "process-based model" - integrates information into the continuing dialogue between physician and patient, vital for diagnosis and treatment. Current medical behaviour often embraces the event-based model, which is considered ineffective and contributes to inappropriateness. We sought, in this review, to analyse from juridical and communication standpoints whether process-based informed consent can deal with scientific uncertainties in radiological decision-making. The informed consent is still a distinctive process in defence of both patients' and physicians' health and dignity in rule-of-law states and consequently in curtailing the abuse of ionising medical radiation. • Inappropriate ionising medical imaging is widespread and increasing worldwide. • This trend leads to noteworthy damage to health and is linked to the issue of patient autonomy. • Some authors have argued that informed consent often falls short of improving patient autonomy. • Process-based informed consent can deal with scientific uncertainties to contrast inappropriateness. • Informed consent is still a distinctive process in defence of both patients and physicians.

  11. JASON XIII: Frozen Worlds (2001-2002). Teacher Pack.

    ERIC Educational Resources Information Center

    JASON Foundation for Education, Needham Heights, MA.

    This teacher's guide and accompanying videotape present the JASON Project. The guide features a workbook format using an interdisciplinary approach to include geography, climate, biology, history, geology, culture, and literature. The JASON Project targets grades 4-9 and involves real life science with the inquiry approach and multimedia…

  12. Yakima Side Channels : Progress Report for 2001-2002.

    SciTech Connect

    Nicolai, Scott

    2003-03-01

    The project objectives include habitat protection and restoration in the most productive reaches of the Yakima Subbasin. The geographic focus includes four reaches in the Yakima, and one in the lower Naches. These areas were identified through studies conducted by WDFW, Yakama Nation, Central Washington University and University of Montana. Research on fish populations and densities, water quality, hyporheic and benthic macro invertebrates suggests that the geographic priorities the most important areas for fish production. Physical characteristics include broad floodplains with multiple channels that flow through extensive riparian/wetland complexes. Geologic characteristics are similar among the reaches, in that they all lie upstream of a ridge that acts to delimit groundwater flow down the stream gradient. Groundwater reemerges in the channel, charging the stream with nutrient-rich and thermally stable water. Many areas have lost key habitat features through various human actions. However strongholds of productivity remain, and in many cases restoration can be undertaken to reconnect the features that made these areas productive. Active habitat restoration actions include reconnecting structurally diverse alcoves and side channels, introducing large woody debris, fencing and revegetation of riparian areas. Priority reaches include Easton, Ellensburg, Selah, Union Gap and on the Naches, the Gleed reach.

  13. Hungry Horse Mitigation; Flathead Lake, 2001-2002 Annual Report.

    SciTech Connect

    Hansen, Barry

    2003-06-09

    The Confederated Salish and Kootenai Tribes (CSKT) and Montana Fish Wildlife and Parks (MFWP) wrote ''Fisheries Mitigation Plan for Losses Attributable to the Construction and Operation of Hungry Horse Dam'' in March 1991 to define the fisheries losses, mitigation alternatives and recommendations to protect, mitigate and enhance resident fish and aquatic habitat affected by Hungry Horse Dam. On November 12, 1991, the Northwest Power Planning Council (NPPC) approved the mitigation plan with minor modifications, called for a detailed implementation plan, and amended measures 903(h)(1) through (7). A long-term mitigation plan was submitted in August 1992, was approved by the Council in 1993, and the first contract for this project was signed on November 11, 1993. The problem this project addresses is the loss of habitat, both in quality and quantity, in the interconnected Flathead Lake and River basin resulting from the construction and operation of Hungry Horse Dam. The purpose of the project is to both implement mitigation measures and monitor the biological responses to those measures including those implemented by Project Numbers 9101903 and 9101904. Goals and objectives of the 1994 Fish and Wildlife Program (Section 10.1) addressed by this project are the rebuilding to sustainable levels weak, but recoverable, native populations injured by the hydropower system. The project mitigates the blockage of spawning runs by Hungry Horse Dam by restoring and even creating spawning habitats within direct drainages to Flathead Lake. The project also addresses the altered habitat within Flathead Lake resulting from species shifts and consequent dominance of new species that restricts the potential success of mitigation measures. Specific goals of this project are to create and restore habitat and quantitatively monitor changes in fish populations to verify the efficacy of our mitigation measures. The project consists of three components: monitoring, restoration and research. Monitoring, for example, includes a spring gillnetting series conducted annually in Flathead Lake and builds on an existing data set initiated in 1981. Monitoring of the experimental kokanee reintroduction was a primary activity of this project between 1992 and 1997. Lake trout, whose high densities have precluded successful mitigation of losses of other species in Flathead Lake, have been monitored since 1996 to measure several biological parameters. Results of this work have utility in determining the population status of this key predator in Flathead Lake. The project has also defined the baseline condition of the Flathead Lake fishery in 1992-1993 and has conducted annual lakewide surveys since 1998. The restoration component of the project has addressed several stream channel, riparian, and fish passage problems. The research component of the project began in FY 2000 and measured trophic linkages between M. relicta and other species to assist in predicting the results of potential mitigation strategies. Only Objective 1 in the workplan is funded entirely by Hungry Horse Mitigation funds. Additional funds are drawn from other sources to assist in completion of Objectives 2-6.

  14. New Jersey Journal of Professional Counseling, 2001/2002.

    ERIC Educational Resources Information Center

    Westburg, Nancy G., Ed.

    2002-01-01

    This journal volume focuses on three areas: technology and the appropriate use of the internet for support groups; diversity issues that affect clients and counselors-in-training; and the clinical issues section that provides an integrated view of Attention Deficit/Hyperactivity Disorder and an overview of Dissociative Identity Disorder. It…

  15. The University School Enaction Curriculum, 2001-2002.

    ERIC Educational Resources Information Center

    Hollingsworth, Patricia L., Ed.

    This document presents the curriculum of the University School at the University of Tulsa (Oklahoma), an early childhood and elementary school for academically gifted students. The curriculum is based on enaction theory, which emphasizes active, interdisciplinary learning involving three steps: (1) concept introduction through active and…

  16. Forrest Ranch Acquisition, Annual Report 2001-2002.

    SciTech Connect

    Smith, Brent

    2003-08-01

    Through their John Day Basin Office, the Confederated Tribes of Warm Springs Reservation of Oregon (Tribes) acquired the Forrest Ranch during July of 2002. The property consists of two parcels located in the John Day subbasin within the Columbia basin. The mainstem parcel consists of 3,503 acres and is located 1/2 mile to the east of Prairie City, Oregon on the mainstem of the John Day River. The middle fork parcel consists of 820 acres and is located one mile to the west of the town of Austin, OR on the middle fork John Day River. The Forrest Ranch Project is under a memorandum of agreement with the Bonneville Power Administration (BPA) to provide an annual written report generally describing the real property interests of the project and management activities undertaken or in progress. The Forrest Ranch acquisition was funded by BPA as part of their program to protect, mitigate, and enhance fish and wildlife habitat affected by the operation of their hydroelectric facilities on the Columbia River and its tributaries. Following lengthy negotiations with the BPA and property owner, the Tribes were able to conclude the acquisition of the Forrest Ranch in July of 2002. The intent of the acquisition project was to partially mitigate fish and wildlife impacts for the John Day Dam on the Columbia River as outlined in the Northwest Power Planning Council's Wildlife Program (NPPC 1994, section 11.1, section 7.6). While the Tribes hold fee-title to the property, the BPA has assured a level of program funding through a memorandum of agreement and annual statement of work. As early as 1997, the Tribes identified this property as a priority for restoration in the John Day basin. In 2000, the Tribes arranged an agreement with the landowner to seek funds for the acquisition of both the Middle Fork and upper Mainstem John Day River holdings of Mr. John Forrest. This property had been a priority of not only the Tribes, but of many other basin natural resource agencies. The contract period was the first year of the program with December 2001 through July 2nd 2002 being previous to acquisition of the property. The majority of the activities conducted under the contract period were spent on O&M and pre acquisition activities.

  17. U.S. Naval Observatory Annual Report 2001-2002

    DTIC Science & Technology

    2002-06-01

    the past year, the FASTT made 39,173 observations of asteroids, and 1,210 of the outer planets Uranus , Neptune, Pluto, and 17 satellites of these...Triton and 8 September 2001 Titania events, as well as for the P126 and P131.1 events for Pluto. All four occulta- tions required expeditions to...moons of Jupiter, Saturn, Uranus , and Neptune with ASTRO- CAM. 4. Sloan Digital Sky Survey (SDSS) J. Munn and J. Pier continued supporting the SDSS

  18. NovaNet Student Outcomes, 2001-2002.

    ERIC Educational Resources Information Center

    Harlow, Kristin; Baenen, Nancy

    NovaNet is an individualized, computer-based instruction program that is used in the Wake County Public School System (WCPSS), North Carolina, for high school course credit, remediation, and enrichment. NovaNet was first used in WCPSS in 1996, and in 1999 WCPSS received a 3-year federal grant to expand the use of NovaNET to all high schools. In…

  19. Fifth Annual Report on School Performance, 2001-2002.

    ERIC Educational Resources Information Center

    Edison Project, New York, NY.

    This report provides a consolidated public record of the performance of Edison-run schools. Edison agrees to provide annually to each local partner comprehensive information about the operation and outcomes of its local partnership schools. Edison is also required by charter-school laws to report on its partnership schools. This report includes…

  20. Graduate Assessment Survey Report Summary, 2001-2002.

    ERIC Educational Resources Information Center

    Santa Fe Community Coll., Gainesville, FL. Office of Institutional Research and Planning.

    This 2001-02 report from Santa Fe Community College (SFCC), Florida, rates student perceptions and opinions of SFCCs classrooms, courses, instructors, academic resources, student services, overall college atmosphere, and cultural atmosphere. Results of the research include the following: (1) of the 2,499 students who responded, 2,229 (89.2%) rated…

  1. Student Financial Aid Handbook for Foreign Schools, 2001-2002.

    ERIC Educational Resources Information Center

    Department of Education, Washington, DC. Student Financial Assistance.

    The purposes of this handbook are to help participating foreign schools achieve manageable, student-friendly administration of the U.S. Federal Family Education Loan (FFEL) Program and to ensure that schools are aware of the legal requirements that pertain to foreign schools participating in the FFEL Program. The FFEL is the only U.S. student…

  2. Colville Tribal Fish Hatchery, 2001-2002 Annual Report.

    SciTech Connect

    Arteburn, John; Christensen, David

    2003-03-01

    Federal hydropower projects as well as private power utility systems have had a major negative impact upon anadromous fish resources that once flourished in the Columbia River and it's tributaries. Several areas have been completely blocked to anadromous fish by dams, destroying the primary food resource (salmon) for many native people forcing them to rely heavily upon resident fish to replace these lost resources. The Colville Tribal Fish Hatchery is an artificial production program that addresses the loss of anadromous fish resources in the Upper Columbia Sub-Region within the ''blocked area'' created by the construction of Chief Joseph and Grand Coulee Dams. This project enhances resident fisheries located in the Intermountain and Columbia Cascade Provinces, specifically within the Colville Reservation portion of the Upper Columbia, SanPoil and Oakanogan Sub-Basins. The project partially mitigates for anadromous fish losses through protection/augmentation of resident fish populations to enhance fishery potential (i.e. in-place, out-of-kind mitigation) pursuant to Resident Fish Substitution Policy of the Northwest Power Planning Councils Fish and Wildlife Program. The hatchery was accepted into the Council's Fish and Wildlife Program in 1984 and the hatchery was completed in 1990. The Colville Tribal Hatchery (CTH) is located on the northern bank of the Columbia River just down stream of the town of Bridgeport, Washington that is just down stream of Chief Joseph Dam. The hatchery is located on land owned by the Colville Tribes. The minimum production quota for this facility is 22,679 kg (50,000 lbs.) of trout annually. All fish produced are released into reservation waters, including boundary waters in an effort to provide a successful subsistence/recreational fishery for Colville Tribal members and provide for a successful nonmember sport fishery. The majority of the fish distributed from the facility are intended to support ''carry-over'' fisheries. Fish produced at the facility are intended to be of sufficient quality and quantity to meet specific monitoring and evaluation goals and objectives outlines in the 2002 statement of work (SOW).

  3. South Carolina State Library Annual Report, 2001-2002.

    ERIC Educational Resources Information Center

    South Carolina State Library, Columbia.

    The current strategic plan of the South Carolina State Library contains five goals: provide information resources and services to meet the needs of the people of South Carolina; provide statewide programs to support local library services; serve as the advocate for libraries in South Carolina; encourage cooperation among libraries of all types;…

  4. Accredited Institutions of Postsecondary Education, Programs, Candidates, 2001-2002.

    ERIC Educational Resources Information Center

    Von Alt, Kenneth A., Ed.

    A comprehensive guide to institutions of higher learning that are accredited by national and regional accrediting agencies, this annual volume has been published since 1964. Data in each entry have been provided by the accrediting bodies. Admissions officers, counselors, and employers rely upon the accurate and up-to-date information in this…

  5. Reference Guide for Integrating Curriculum, 2001-2002. [Grade] 8.

    ERIC Educational Resources Information Center

    North Carolina State Board of Education, Raleigh.

    This reference guide is designed to help eighth grade teachers plan for instruction, providing all of the goals and objectives in one document. The guide can be used to link instructional objectives across disciplines, plan integrated units, and assist in assessing student progress over time. Only the very basic components of each discipline…

  6. Project Achieve Evaluation Report: Year One, 2001-2002.

    ERIC Educational Resources Information Center

    Speas, Carol

    This report is an evaluation of the pilot year of Project Achieve, a major local instructional initiative at six elementary schools and two middle schools in the Wake County Public School System (WCPSS), North Carolina, that was designed to help reach the WCPSS goal of 95% of students at or above grade level. Participating schools had a higher…

  7. Kindergarten Education: Theory, Research, and Practice, 2001-2002.

    ERIC Educational Resources Information Center

    Robinson, Violet B., Ed.

    2001-01-01

    This document is comprised of the two issues of a biannually published journal featuring research studies, theoretical essays, and classroom practice articles about the development and education of kindergarten children as well as occasional articles concerning preschool and the early primary grades. The Spring/Summer 2001 issue contains the…

  8. Youth tobacco surveillance--United States, 2001-2002.

    PubMed

    Marshall, LaTisha; Schooley, Michael; Ryan, Heather; Cox, Patrick; Easton, Alyssa; Healton, Cheryl; Jackson, Kat; Davis, Kevin C; Homsi, Ghada

    2006-05-19

    Cigarette smoking is the leading preventable cause of death in the United States, accounting for approximately 440,000 deaths each year. The prevalence of cigarette smoking nationwide among high school students (grades 9-12) increased during the 1990s, peaking during 1996-1997, and then declined. Approximately 80% of tobacco users initiate use before age 18 years. An estimated 6.4 million children aged <18 years who are living today will die prematurely as adults because they began to smoke cigarettes during adolescence. The annual health-related economic cost associated with tobacco use exceeds 167 billion dollars. Because of these health and economic consequences, CDC has recommended that states establish and maintain comprehensive tobacco-control programs to reduce tobacco use among youth. This report covers data collected during January 2001-December 2002. The National Youth Tobacco Survey (NYTS) and state youth tobacco surveys (YTS) were developed to provide states with data to support the design, implementation, and evaluation of comprehensive tobacco-control programs. NYTS is representative of middle and high school students in the 50 states and the District of Columbia. During spring 2002, a total of 26,149 students in 246 schools completed NYTS questionnaires. Weighted data for the YTS were achieved by 13 states in 2001 and by 20 states in 2002; state sample sizes varied (range: 982-38,934). This report summarizes data from the 2002 NYTS and the 2001 and 2002 YTS. Findings from the 2002 NYTS indicate that current use of any tobacco product ranged from 13.3% among middle school students to 28.2% among high school students. Cigarette smoking was the most prevalent form of tobacco use, with 9.8% of middle school students and 22.5% of high school students reporting that they currently smoke cigarettes. Cigar smoking was the second most prevalent form of tobacco use, with 6.0% of middle school students and 11.6% of high school students reporting that they currently smoke cigars. Among current cigarette smokers, 41.8% of middle school students and 52.0% of high school students reported that they usually smoke Marlboro cigarettes. Black middle school and high school students who smoke were more likely to smoke Newport cigarettes than any other brand (58.3% and 66.8%, respectively). Among middle school students aged <18 years, 75.9% were not asked to show proof of age when they bought or tried to buy cigarettes, and 63.4% were not refused purchase because of their age. Among high school students aged <18 years, 58.5% were not asked to show proof of age when they bought or tried to buy cigarettes, and 60.6% were not refused purchase because of their age. Nearly half (49.6%) of middle school students and 62.1% of high school students who smoke reported a desire to stop smoking cigarettes, with 55.4% of middle school students and 53.1% of high school students reported having made at least one cessation attempt during the 12 months preceding the survey. Among students who have never smoked cigarettes, 21.3% of middle school students and 22.9% of high school students were susceptible to initiating cigarette smoking in the next year. Exposure to secondhand smoke (i.e., environmental tobacco smoke) was high. During the week before the survey, 1) 88.3% of middle school students and 91.4% of high school students who currently smoke cigarettes and 47.1% of middle school students and 53.3% of high school students who have never smoked cigarettes were in the same room with someone who was smoking cigarettes; 2) 81.7% of middle school students and 83.7% of high school students who currently smoke cigarettes and 31.5% of middle school students and 29.1% of high school students who have never smoked cigarettes rode in a car with someone who was smoking cigarettes; and 3) 71.5% of middle school students and 57.5% of high school students who currently smoke cigarettes and 33.3% of middle school students and 29.9% of high school students who have never smoked cigarettes lived in a home in which someone else smoked cigarettes. Media and advertising influence was also noted, with 58.1% of middle school students and 54.9% of high school students who currently use tobacco and 11.0% of middle school students and 13.7% of high school students who have never used tobacco reporting that they would wear or use an item with a tobacco company name or logo on it. Although 84.6% of middle school students and 91.2% of high school students had seen or heard antismoking commercials on television or radio, 89.9% of middle school students and 91.3% of high school students also had seen actors using tobacco on television or in the movies. Health and education officials use YTS and NYTS data to plan, evaluate, and improve national and state programs to prevent and control youth tobacco use. States can use these data in presentations to their state legislators to demonstrate the need for funding comprehensive tobacco-control programs, including tobacco cessation and prevention programs for youth.

  9. American Dental Education Association Annual Proceedings, 2001-2002.

    ERIC Educational Resources Information Center

    Journal of Dental Education, 2002

    2002-01-01

    Reports activities of the American Dental Education Association (ADEA) from the end of the 2001 Annual Session and Exposition (March 9, 2001) through the 2002 Annual Session and Exposition (March 7, 2002). Consists of: president's annual report, president-elect's address, executive director's report, proceedings of the 2002 House of Delegates,…

  10. WDS Annual Report to the General Assembly, 2001-2002.

    ERIC Educational Resources Information Center

    Virginia Community Coll. System, Richmond.

    This document discusses the Virginia Community College System (VCCS) and how it has become the lead agency in workforce development for Virginia as well as advancing Virginia's workforce through non-credit training, retaining courses and programs to meet the needs of business and industry. This document contains a summary of activities and…

  11. Radiation

    NASA Image and Video Library

    Outside the protective cocoon of Earth's atmosphere, the universe is full of harmful radiation. Astronauts who live and work in space are exposed not only to ultraviolet rays but also to space radi...

  12. Radiation dose and radiation protection principle awareness: a survey among Nigerian paediatricians.

    PubMed

    Famurewa, O C; Obiajunwa, P O; Elusiyan, J B; Ibitoye, B O

    2014-03-01

    This study is aimed at determining the knowledge of Paediatricians in Nigeria about the basic principle of radiation protection ALARA (As Low As Reasonably Achievable) and their knowledge of the radiation doses that children receive during some common radiological procedures. Two hundred and fifty questionnaires were circulated among paediatricians at the 2012 annual Paediatricians' Association of Nigeria Conference. The questionnaires contain 10 questions designed to asses the pediatricians' general knowledge on : ionising radiation and the risks, doses children receive during some common radiological procedures and awareness of the radiation protection principle, ALARA ( As Low As Reasonably Achievable). Of the 162 Paediatricians that participated, 69% named at least one non medical source of ionising radiation, 54.9% would not recommend CXR to screen an apparently healthy child for tuberculosis and 87% believe that children are at greater risk of adverse effects of ionising radiation. For dose estimation, 51.9% and 51.2% of the paediatricians underestimated doses received during Cranial and abdominal computerised tomography respectively while 13.6% and 37% respectively erroneously believed that abdominal ultrasound and brain magnetic resonance imaging utilise ionising radiation. 13.6% gave the correct meaning of the Acronym ALARA. The Paediatricians' knowledge about the basic principle of radiation protection ALARA and the doses that children receive during some common radiological procedures is poor. There is need to ensure adequate training on radiation hazards and protection at all levels of medical education.

  13. Transferring calibration coefficients from ionisation chambers used for diagnostic radiology to transmission chambers.

    PubMed

    Yoshizumi, Maíra T; Caldas, Linda V E

    2012-07-01

    In this work, the response of a double volume transmission ionisation chamber, developed at the Instituto de Pesquisas Energéticas e Nucleares, was compared to that of a commercial transmission chamber. Both ionisation chambers were tested in different X-ray beam qualities using secondary standard ionisation chambers as reference dosimeters. These standard ionisation chambers were a parallel-plate and a cylindrical ionisation chambers, used for diagnostic radiology and mammography beam qualities, respectively. The response of both transmission chambers was compared to that of the secondary standard chambers to obtain coefficients of equivalence. These coefficients allow the transmission chambers to be used as reference equipment. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. Radiation-induced cardiovascular effects

    NASA Astrophysics Data System (ADS)

    Tapio, Soile

    Recent epidemiological studies indicate that exposure to ionising radiation enhances the risk of cardiovascular mortality and morbidity in a moderate but significant manner. Our goal is to identify molecular mechanisms involved in the pathogenesis of radiation-induced cardiovascular disease using cellular and mouse models. Two radiation targets are studied in detail: the vascular endothelium that plays a pivotal role in the regulation of cardiac function, and the myocardium, in particular damage to the cardiac mitochondria. Ionising radiation causes immediate and persistent alterations in several biological pathways in the endothelium in a dose- and dose-rate dependent manner. High acute and cumulative doses result in rapid, non-transient remodelling of the endothelial cytoskeleton, as well as increased lipid peroxidation and protein oxidation of the heart tissue, independent of whether exposure is local or total body. Proteomic and functional changes are observed in lipid metabolism, glycolysis, mitochondrial function (respiration, ROS production etc.), oxidative stress, cellular adhesion, and cellular structure. The transcriptional regulators Akt and PPAR alpha seem to play a central role in the radiation-response of the endothelium and myocardium, respectively. We have recently started co-operation with GSI in Darmstadt to study the effect of heavy ions on the endothelium. Our research will facilitate the identification of biomarkers associated with adverse cardiac effects of ionising radiation and may lead to the development of countermeasures against radiation-induced cardiac damage.

  15. Electron impact ionisation cross sections of iron hydrogen clusters

    NASA Astrophysics Data System (ADS)

    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, FeH n 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 4 s 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.

  16. Photo-ionisation mass spectrometry as detection method for gas chromatography. Optical selectivity and multidimensional comprehensive separations.

    PubMed

    Zimmermann, Ralf; Welthagen, Werner; Gröger, Thomas

    2008-03-14

    Mass spectrometry (MS) with soft ionisation techniques (i.e. ionisation without fragmentation of the analyte molecules) for gaseous samples exhibits interesting analytical properties for direct analysis applications (i.e. direct inlet mass spectrometric on-line monitoring) as well as mass spectrometric detection method for gas chromatography (GC-MS). Commonly either chemical ionisation (CI) or field ionisation (FI) is applied as soft ionisation technology for GC-MS. An interesting alternative to the CI and FI technologies methods are photo-ionisation (PI) methods. PI overcomes some of the limitations of CI and FI and furthermore add some unique analytical properties. The resonance enhanced multi-photon ionisation (REMPI) method uses intense UV-laser pulses (wavelength range approximately 350-193 nm) for highly selective, sensitive and soft ionisation of predominately aromatic compounds. The single photon ionisation (SPI) method utilises VUV light (from lamps or laser sources, wavelengths range approximately 150-110 nm) can be used for a universal soft ionisation of organic molecules. In this article the historical development as well as the current status and concepts of gas chromatography hyphenated to photo-ionisation mass spectrometry are reviewed.

  17. Differential ionisation of natural antioxidant polyenes in electrospray and nanospray mass spectrometry.

    PubMed

    Guaratini, Thais; Gates, Paul J; Pinto, Ernani; Colepicolo, Pio; Lopes, Norberto P

    2007-01-01

    Carotenoids are natural products with high economic relevance for the pharmaceutical industries and are a common subject for biochemical research. Reported here is a comparative study of the ionisation of carotenoids by electrospray mass spectrometry (ESI-MS) and nanospray mass spectrometry (nanoESI-MS). The results demonstrate that, along with solvent choice, the influence of the different ionisation processes of ESI and nanoESI are fundamental in determining how ionisation is achieved and which ions (molecular ion or protonated molecule) are observed in MS. The increased understanding afforded by this study will help in the development of unequivocal microanalytical methods for carotenoids and related antioxidant polyenes.

  18. Predictive value of derived calcium figures based on the measurement of ionised calcium.

    PubMed

    Gardner, M D; Dryburgh, F J; Fyffe, J A; Jenkins, A S

    1981-03-01

    The algorithms used in this hospital to assess calcium status are calculated ionised serum calcium and the serum calcium concentration adjusted for albumin. In order to establish their clinical usefulness, they were compared with the ionised calcium concentration measured on the Nova 2 instrument in patients with various calcium and protein abnormalities. Good correlation was found between the measured and calculated values. The predictive values for the calculated results and for total serum calcium concentrations are presented. In this series, the derived values were useful in predicting the serum ionised calcium concentration of the patients studied.

  19. Ionisation effect on the electron localisation in the subcycle waveform shaping scheme

    NASA Astrophysics Data System (ADS)

    Wang, Zhuo; Feng, Zhengpeng; Long, Hua

    2015-03-01

    We have theoretically studied the ionisation effect on the asymmetric dissociation of H+2 exposed to the synthesised multicycle infrared pulses of different wavelengths by solving the time-dependent Schr?dinger equation without using the Born-Oppenheimer approximation. It has been demonstrated that the ionisation does slightly influence the electron localisation for the relatively low pulse intensity (less than 1014 W/cm2). However, our further results show that the ionisation effect becomes much more significant when increasing the pulse intensity, leading to a distinctly different mechanism responsible for the enhancement of the electron localisation.

  20. 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

    NASA Astrophysics Data System (ADS)

    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

  1. Ionisation Mechanisms in AN Optically Pumped Mercury Vapour.

    NASA Astrophysics Data System (ADS)

    Counsell, G. F.

    Available from UMI in association with The British Library. Requires signed TDF. A plasma formed in a mercury vapour by optical pumping at visible and U.V. wavelengths from a high current mercury discharge, has been investigated with a view to gaining an understanding of the ionisation processes giving rise to the plasma. These were believed to generate both atomic and molecular ions. The results of this work have applications in the fields of fluorescent lighting and the mercury-nitrogen laser. The plasma was studied with a variety of diagnostic tools. Electron number densities and temperatures were determined using Langmuir probes operating in the orbital motion limited regime. Populations of the 6^3 P triplet states, believed to be the only significantly populated excited states in the plasma, were determined using absorption spectroscopy. Lastly, a quadrupole mass spectrometer, coupled to the plasma with an electrostatic ion transport system, was used to investigate the flux of atomic and molecular ions to a body at floating potential in the plasma. The Langmuir probe and absorption spectroscopy results were included into a model describing ion motions in the plasma, based around the ion fluid equations and including source terms for the generation of atomic and molecular ions, both by electron impact and by binary collisions of atoms in the 6^3P triplet states. Where possible, ionisation rats in the model were calculated using published cross-sections. However, for the heavy body collisional processes in particular, many of these are unknown. Consequently, an attempt was made to determine these cross-sections by generating results from the model that could be compared to experimental measurements of the atomic and molecular ion fluxes to the mass spectrometer. A number of computational experiments were carried out, varying the cross-sections until a good fit to the experimental measurements was achieved. Using this technique it was possible to estimate cross

  2. Recombination in liquid filled ionisation chambers with multiple charge carrier species: Theoretical and numerical results

    NASA Astrophysics Data System (ADS)

    Aguiar, P.; González-Castaño, D. M.; Gómez, F.; Pardo-Montero, J.

    2014-10-01

    Liquid-filled ionisation chambers (LICs) are used in radiotherapy for dosimetry and quality assurance. Volume recombination can be quite important in LICs for moderate dose rates, causing non-linearities in the dose rate response of these detectors, and needs to be corrected for. This effect is usually described with Greening and Boag models for continuous and pulsed radiation respectively. Such models assume that the charge is carried by two different species, positive and negative ions, each of those species with a given mobility. However, LICs operating in non-ultrapure mode can contain different types of electronegative impurities with different mobilities, thus increasing the number of different charge carriers. If this is the case, Greening and Boag models can be no longer valid and need to be reformulated. In this work we present a theoretical and numerical study of volume recombination in parallel-plate LICs with multiple charge carrier species, extending Boag and Greening models. Results from a recent publication that reported three different mobilities in an isooctane-filled LIC have been used to study the effect of extra carrier species on recombination. We have found that in pulsed beams the inclusion of extra mobilities does not affect volume recombination much, a behaviour that was expected because Boag formula for charge collection efficiency does not depend on the mobilities of the charge carriers if the Debye relationship between mobilities and recombination constant holds. This is not the case in continuous radiation, where the presence of extra charge carrier species significantly affects the amount of volume recombination.

  3. Ionisation Chambers and Secondary Emission Monitors at the PROSCAN Beam Lines

    NASA Astrophysics Data System (ADS)

    Dölling, Rudolf

    2006-11-01

    PROSCAN, the dedicated new medical facility at PSI using proton beams for the treatment of deep seated tumours and eye melanoma, is now in the commissioning phase. Air filled ionisation chambers in several configurations are used as current monitors, profile monitors, halo, position and loss monitors at the PROSCAN beam lines. Similar monitors based on secondary emission are used for profile and current measurements in the regime where saturation deteriorates the accuracy of the ionisation chambers.

  4. Gastrointestinal radiation injury: Prevention and treatment

    PubMed Central

    Shadad, Abobakr K; Sullivan, Frank J; Martin, Joseph D; Egan, Laurence J

    2013-01-01

    With the recent advances in detection and treatment of cancer, there is an increasing emphasis on the efficacy and safety aspects of cancer therapy. Radiation therapy is a common treatment for a wide variety of cancers, either alone or in combination with other treatments. Ionising radiation injury to the gastrointestinal tract is a frequent side effect of radiation therapy and a considerable proportion of patients suffer acute or chronic gastrointestinal symptoms as a result. These side effects often cause morbidity and may in some cases lower the efficacy of radiotherapy treatment. Radiation injury to the gastrointestinal tract can be minimised by either of two strategies: technical strategies which aim to physically shift radiation dose away from the normal intestinal tissues, and biological strategies which aim to modulate the normal tissue response to ionising radiation or to increase its resistance to it. Although considerable improvement in the safety of radiotherapy treatment has been achieved through the use of modern optimised planning and delivery techniques, biological techniques may offer additional further promise. Different agents have been used to prevent or minimize the severity of gastrointestinal injury induced by ionising radiation exposure, including biological, chemical and pharmacological agents. In this review we aim to discuss various technical strategies to prevent gastrointestinal injury during cancer radiotherapy, examine the different therapeutic options for acute and chronic gastrointestinal radiation injury and outline some examples of research directions and considerations for prevention at a pre-clinical level. PMID:23345942

  5. Excitation and Ionisation dynamics in high-frequency plasmas

    NASA Astrophysics Data System (ADS)

    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

  6. Fundamentals of Radiation Dosimetry

    NASA Astrophysics Data System (ADS)

    Bos, Adrie J. J.

    2011-05-01

    The basic concepts of radiation dosimetry are reviewed on basis of ICRU reports and text books. The radiation field is described with, among others, the particle fluence. Cross sections for indirectly ionizing radiation are defined and indicated is how they are related to the mass energy transfer and mass energy absorption coefficients. Definitions of total and restricted mass stopping powers of directly ionizing radiation are given. The dosimetric quantities, kerma, absorbed dose and exposure together with the relations between them are discussed in depth. Finally it is indicated how the absorbed dose can be measured with a calorimeter by measuring the temperature increase and with an ionisation chamber measuring the charge produced by the ionizing radiation and making use of the Bragg-Gray relation.

  7. Fundamentals of Radiation Dosimetry

    SciTech Connect

    Bos, Adrie J. J.

    2011-05-05

    The basic concepts of radiation dosimetry are reviewed on basis of ICRU reports and text books. The radiation field is described with, among others, the particle fluence. Cross sections for indirectly ionizing radiation are defined and indicated is how they are related to the mass energy transfer and mass energy absorption coefficients. Definitions of total and restricted mass stopping powers of directly ionizing radiation are given. The dosimetric quantities, kerma, absorbed dose and exposure together with the relations between them are discussed in depth. Finally it is indicated how the absorbed dose can be measured with a calorimeter by measuring the temperature increase and with an ionisation chamber measuring the charge produced by the ionizing radiation and making use of the Bragg-Gray relation.

  8. Predicted ionisation in mitochondria and observed acute changes in the mitochondrial transcriptome after gamma irradiation: a Monte Carlo simulation and quantitative PCR study.

    PubMed

    Kam, Winnie Wai-Ying; McNamara, Aimee L; Lake, Vanessa; Banos, Connie; Davies, Justin B; Kuncic, Zdenka; Banati, Richard B

    2013-11-01

    It is a widely accepted that the cell nucleus is the primary site of radiation damage while extra-nuclear radiation effects are not yet systematically included into models of radiation damage. We performed Monte Carlo simulations assuming a spherical cell (diameter 11.5 μm) modelled after JURKAT cells with the inclusion of realistic elemental composition data based on published literature. The cell model consists of cytoplasm (density 1g/cm(3)), nucleus (diameter 8.5 μm; 40% of cell volume) as well as cylindrical mitochondria (diameter 1 μm; volume 0.5 μm(3)) of three different densities (1, 2 and 10 g/cm(3)) and total mitochondrial volume relative to the cell volume (10, 20, 30%). Our simulation predicts that if mitochondria take up more than 20% of a cell's volume, ionisation events will be the preferentially located in mitochondria rather than in the cell nucleus. Using quantitative polymerase chain reaction, we substantiate in JURKAT cells that human mitochondria respond to gamma radiation with early (within 30 min) differential changes in the expression levels of 18 mitochondrially encoded genes, whereby the number of regulated genes varies in a dose-dependent but non-linear pattern (10 Gy: 1 gene; 50 Gy: 5 genes; 100 Gy: 12 genes). The simulation data as well as the experimental observations suggest that current models of acute radiation effects, which largely focus on nuclear effects, might benefit from more systematic considerations of the early mitochondrial responses and how these may subsequently determine cell response to ionising radiation.

  9. Simultaneous radar and video meteors—II: Photometry and ionisation

    NASA Astrophysics Data System (ADS)

    Weryk, Robert J.; Brown, Peter G.

    2013-06-01

    Simultaneous radar and video measurements of meteors were made using the Canadian Meteor Orbit Radar (CMOR) and several Gen-III image-intensified CCD cameras primarily to relate radar meteor electron line density, q, to video meteor photon radiant power, I. We find that log10q=log10I+(12.56±0.49) leading to M=(38.7±1.2)-2.5log10q, where M is the meteor magnitude in the Gen-III video bandpass (470-850 nm) corresponding to q at the radar specular point. The ratio of the ionisation coefficient to luminous efficiency, β/τI, was estimated from our observations of q/I to functionally depend on speed and radiant power. For our average meteor photon radiant power of I=64W, we find log10β/τI=(3.00±0.62)log10v-(4.27±1.37). By adopting β computed according to Jones (1997), which we approximate as log10β=5.84-0.09v0.5-9.56/log10v (roughly proportional to v4 between 20 and 40 km/s), a corresponding estimate of τI for our intensified spectral bandpass was made using our measurements of q/I. We find a peak bolometric value of τI=5.9% at 41 km/s. The main uncertainties associated with our analysis are the unknown spectra of individual meteors which affect our estimate of absolute radiant power, and uncertain values of the initial trail radius which makes estimates of q problematic. Our results suggest that the video meteor mass scale is an order of magnitude smaller than previously thought at these higher speeds, and implies that the total meteoroid mass influx between 10-5 and 10-8kg is lower than previous studies would suggest.

  10. Comparison of ionisation chamber and semiconductor detector devices for measurement of the dose-width product for panoramic dental units.

    PubMed

    Mitchell, S A; Martin, C J

    2013-06-01

    Doses for panoramic dental radiography are assessed in terms of the dose-width product (DWP) or dose-area product, which gives a measure of the radiation through a whole exposure. The DWP can be measured using a pencil ionisation chamber (IC) similar to that used for computed tomography dose assessment. However, ICs are sensitive to radiation incident from all directions and so backscatter from the image receptor may increase the recorded dose. This study compares measurements performed using four options: a pencil IC mounted straight on the image receptor, the IC mounted with a steel plate to the rear to standardise scatter conditions, the IC mounted with a steel plate and lead collimators in front to minimise the effect of extra-focal radiation, and a Quart Dido employing a one square centimetre semiconductor detector (SD) designed for panoramic measurements. The results indicate that modification of the current method by incorporating a steel plate reduced the measurement dose by 7% on average, but the reduction was greater for units with semiconductor imaging plates. The measurements with the SD agree more closely with the IC with the steel plate to the rear. An IC with a backing plate to standardise scatter or a suitable SD is recommended for measurement on panoramic dental units.

  11. Development of a new ionisation chamber, for HP(10) measurement, using Monte-Carlo simulation and experimental methods.

    PubMed

    Silva, H; Cardoso, J; Oliveira, C

    2011-03-01

    An ionisation chamber that directly measures the quantity personal dose equivalent, H(p)(10), is used as a secondary standard in some metrology laboratories. An ionisation chamber of this type was first developed by Ankerhold. Using the Monte-Carlo simulation, the dose in the sensitive volume as a function of the IC dimensions and the effects of the several components of the ionising chamber have been investigated. Based on these results, a new ionising chamber, lighter than the previous ones, is constructed and experimentally tested.

  12. Surface ionisation of molecular H2 and atomic H Rydberg states at doped silicon surfaces

    NASA Astrophysics Data System (ADS)

    Sashikesh, G.; So, E.; Ford, M. S.; Softley, T. P.

    2014-09-01

    The detection of ions or electrons from the surface ionisation of molecular H2 and atomic H Rydberg states incident at doped Si surfaces is investigated experimentally to analyse the effect of the dopant charge distribution on the surface-ionisation processes. In both experimental studies, the molecular H2 and atomic H Rydberg states are generated via two-colour vacuum ultraviolet--ultraviolet (VUV-UV) resonant excitation. For H2, various Stark states of the N+ = 2, n = 17 manifold are populated in the presence of an electric field. The variation of the observed surface-ionisation signal with surface dopant concentration and type, shows similar characteristics for all the Stark states. A comparison is made between these ion-detected surface-ionisation profiles and those obtained via electron detection. Different trends as a function of dopant concentration and type are observed for the two cases, explained by the greater effect of surface charges on the post-ionisation ion trajectory compared to the electron trajectory. For the atomic-H Rydberg states with principal quantum number ? populated in the absence of a Stark field, the observed behaviour is similar to the interaction of molecular H2 Rydberg states at the same surfaces, and these measurements confirm that the observed effects are attributable to the nature of the target surface rather than the specific atomic or molecular Rydberg species.

  13. Total ionisation cross sections for chlorofluoromethanes and CClx radicals by electron impact

    NASA Astrophysics Data System (ADS)

    Gupta, Dhanoj; Antony, Bobby

    2014-07-01

    We report here the total ionisation cross section for chlorofluoromethanes, namely CCl3F (Freon 11), CCl2F2 (Freon 12), CClF3 (Freon 13), CHCl2F (Freon 21), CHClF2 (Freon 22), CH2ClF (Freon 31), CCl4 and CClx (x = 1-3), radicals by electron impact from ionisation threshold to 2 keV. The total inelastic cross section is obtained employing a complex optical potential formalism and solving the Schrödinger equation through partial wave analysis. Using the complex scattering potential-ionisation contribution method, the total ionisation cross section is derived from the inelastic cross section for these targets. The results obtained are then compared with the existing experimental and theoretical data, wherever available. The present result shows reasonable agreement with previous data. For the CClx radicals, the ionisation cross section is predicted for the first time. The data reported here have immense interest to atmospheric and technological plasma modelling.

  14. Ionising irradiation alters the dynamics of human long interspersed nuclear elements 1 (LINE1) retrotransposon.

    PubMed

    Tanaka, Atsushi; Nakatani, Youko; Hamada, Nobuyuki; Jinno-Oue, Atsushi; Shimizu, Nobuaki; Wada, Seiichi; Funayama, Tomoo; Mori, Takahisa; Islam, Salequl; Hoque, Sheikh Ariful; Shinagawa, Masahiko; Ohtsuki, Takahiro; Kobayashi, Yasuhiko; Hoshino, Hiroo

    2012-09-01

    It is important to identify the mechanism by which ionising irradiation induces various genomic alterations in the progeny of surviving cells. Ionising irradiation activates mobile elements like retrotransposons, although the mechanism of its phenomena consisting of transcriptions and insertions of the products into new sites of the genome remains unclear. In this study, we analysed the effects of sparsely ionising X-rays and densely ionising carbon-ion beams on the activities of a family of active retrotransposons, long interspersed nuclear elements 1 (L1). We used the L1/reporter knock-in human glioma cell line, NP-2/L1RP-enhanced GFP (EGFP), that harbours full-length L1 tagged with EGFP retrotransposition detection cassette (L1RP-EGFP) in the chromosomal DNA. X-rays and carbon-ion beams similarly increased frequencies the transcription from L1RP-EGFP and its retrotransposition. Short-sized de novo L1RP-EGFP insertions with 5'-truncation were induced by X-rays, while full-length or long-sized insertions (>5 kb, containing ORF1 and ORF2) were found only in cell clones irradiated by the carbon-ion beams. These data suggest that X-rays and carbon-ion beams induce different length of de novo L1 insertions, respectively. Our findings thus highlight the necessity to investigate the mechanisms of mutations caused by transposable elements by ionising irradiation.

  15. Impact ionisation mass spectrometry of polypyrrole-coated pyrrhotite microparticles

    NASA Astrophysics Data System (ADS)

    Hillier, Jon K.; Sternovsky, Zoltan; Armes, Steven P.; Fielding, Lee A.; Postberg, Frank; Bugiel, Sebastian; Drake, Keith; Srama, Ralf; Kearsley, Anton T.; Trieloff, Mario

    2014-07-01

    Cation and anion impact ionization mass spectra of polypyrrole-coated pyrrhotite cosmic dust analogue particles are analysed over a range of cosmically relevant impact speeds. Spectra with mass resolutions of 150-300 were generated by hypervelocity impacts of charged particles, accelerated to up to 37 km s-1 in a Van de Graaff electrostatic accelerator, onto a silver target plate in the Large Area Mass Analyzer (LAMA) spectrometer. Ions clearly indicative of the polypyrrole overlayer are identified at masses of 93, 105, 117, 128 and 141 u. Organic species, predominantly derived from the thin (20 nm) polypyrrole layer on the surface of the particles, dominate the anion spectra even at high (>20 km s-1) impact velocities and contribute significantly to the cation spectra at velocities lower than this. Atomic species from the pyrrhotite core (Fe and S) are visible in all spectra at impact velocities above 6 km s-1 for 56Fe+, 9 km s-1 for 32S+ and 16 km s-1 for 32S- ions. Species from the pyrrhotite core are also frequently visible in cation spectra at impact speeds at which surface ionisation is believed to dominate (<10 km s-1), although the large number of organic peaks complicates the identification of characteristic molecular species. A thin oxidised surface layer on the pyrrhotite particles is indicated by weak spectral features assigned to iron oxides and iron oxy-hydroxides, although the definitive identification of sulfates and hydrated sulfates from the oxidation process was not possible. Silver was confirmed as an excellent choice for the target plate of an impact ionization mass spectrometer, as it provided a unique isotope signature for many target-projectile cluster peaks at masses above 107-109 u. The affinity of Ag towards a dominant organic fragment ion (CN-) derived from fragmentation of the polypyrrole component led to molecular cluster formation. This resulted in an enhanced sensitivity to a particular particle component, which may be of great use

  16. Dynamics of ionisation and entanglement in the 'atom + quantum electromagnetic field' system

    SciTech Connect

    Sharapova, P R; Tikhonova, O V

    2012-03-31

    The dynamics of a model Rydberg atom in a strong nonclassical electromagnetic field is investigated. The field-induced transitions to the continuum involving different numbers of photons (with intermediate states in the discrete spectrum) are taken into account and the specific features of ionisation in 'squeezed' field states are considered in comparison with the case of classical light. A significant decrease in the ionisation rate is found, which is caused by the interference stabilisation of the atomic system. The entanglement of the atomic and field subsystems, the temporal dynamics of the correlations found, and the possibility of measuring them are analysed.

  17. Molybdic acid ionisation under hydrothermal conditions to 300 °C

    NASA Astrophysics Data System (ADS)

    Minubayeva, Z.; Seward, T. M.

    2010-08-01

    This UV spectrophotometric study was aimed at providing precise, experimentally derived thermodynamic data for the ionisation of molybdic acid (H 2MoO 4) from 30 to 300 °C and at equilibrium saturated vapour pressures. The determination of the equilibrium constants and associated thermodynamic parameters were facilitated by spectrophotometric measurements using a specially designed high temperature optical Ti-Pd flow-through cell with silica glass windows. The following van't Hoff isochore equations describe the temperature dependence of the first and second ionisation constants of molybdic acid up to 300 °C:

  18. A micro-gap, air-filled ionisation chamber as a detector for criticality accident dosimetry.

    PubMed

    Murawski, Ł; Zielczyński, M; Golnik, N; Gryziński, M A

    2014-10-01

    A micro-gap air-filled ionisation chamber was designed for criticality dosimetry. The special feature of the chamber is its very small gap between electrodes of only 0.3 mm. This prevents ion recombination at high dose rates and minimises the influence of gas on secondary particles spectrum. The electrodes are made of polypropylene because of higher content of hydrogen in this material, when compared with soft tissue. The difference between neutron and gamma sensitivity in such chamber becomes practically negligible. The chamber's envelope contains two specially connected capacitors, one for polarising the electrodes and the other for collecting the ionisation charge.

  19. CT radiation dose awareness among paediatricians.

    PubMed

    Al-Rammah, Tamader Y

    2016-08-31

    The radiation dose delivered from computed tomography (CT) scanning and the risks associated with ionising radiation are major concerns in paediatric imaging. Compared to adults, children have increased organ sensitivity and a longer expected lifetime in which cancer may develop. Therefore, it is important to investigate the awareness of paediatricians (referring physicians) regarding radiation doses and the associated risks. A multiple-choice survey was distributed among paediatricians in 8 hospitals in Riyadh, the capital of Saudi Arabia. Among the 162 respondents, only 24 (15 %) were aware of the As Low As Reasonably Achievable (ALARA) principle. Approximately half (54 %) of the respondents believed that multi-slice CT delivered a low radiation dose, and 100 (62 %) of the respondents were not aware that radiation is considered carcinogenic by the Food and Drug Administration in the United States. Among the respondents, 110 (68 %) did not have any specific education regarding radiation during their training. There was an overall underestimation (83 %) of the CT radiation dose, and 70 % thought that magnetic resonance imaging (MRI) delivered some level of ionising radiation. Among paediatricians in Saudi Arabian hospitals, there was a wide underestimation of the CT radiation dose and the associated risks for children. We should improve paediatricians' knowledge about radiation doses. Radiologists, paediatricians, radiation technologists and medical physicists should work together to optimise CT guidelines and protocols to reduce the radiation risks for children.

  20. Biological consequences of radiation-induced DNA damage: relevance to radiotherapy.

    PubMed

    Lomax, M E; Folkes, L K; O'Neill, P

    2013-10-01

    DNA damage of exposed tumour tissue leading to cell death is one of the detrimental effects of ionising radiation that is exploited, with beneficial consequences, for radiotherapy. The pattern of the discrete energy depositions during passage of the ionising track of radiation defines the spatial distribution of lesions induced in DNA with a fraction of the DNA damage sites containing clusters of lesions, formed over a few nanometres, against a background of endogenously induced individual lesions. These clustered DNA damage sites, which may be considered as a signature of ionising radiation, underlie the deleterious biological consequences of ionising radiation. The concepts developed rely in part on the fact that ionising radiation creates significant levels of clustered DNA damage, including complex double-strand breaks (DSB), to kill tumour cells as clustered damage sites are difficult to repair. This reduced repairability of clustered DNA damage using specific repair pathways is exploitable in radiotherapy for the treatment of cancer. We discuss some potential strategies to enhance radiosensitivity by targeting the repair pathways of radiation-induced clustered damage and complex DNA DSB, through inhibition of specific proteins that are not required in the repair pathways for endogenous damage. The variety and severity of DNA damage from ionising radiation is also influenced by the tumour microenvironment, being especially sensitive to the oxygen status of the cells. For instance, nitric oxide is known to influence the types of damage induced by radiation under hypoxic conditions. A potential strategy based on bioreductive activation of pro-drugs to release nitric oxide is discussed as an approach to deliver nitric oxide to hypoxic tumours during radiotherapy. The ultimate aim of this review is to stimulate thinking on how knowledge of the complexity of radiation-induced DNA damage may contribute to the development of adjuncts to radiotherapy. Copyright

  1. Common strategic research agenda for radiation protection in medicine.

    PubMed

    2017-04-01

    Reflecting the change in funding strategies for European research projects, and the goal to jointly improve medical radiation protection through sustainable research efforts, five medical societies involved in the application of ionising radiation (European Association of Nuclear Medicine, EANM; European Federation of Organizations for Medical Physics. EFOMP; European Federation of Radiographer Societies, EFRS; European Society of Radiology, ESR; European Society for Radiotherapy and Oncology, ESTRO) have identified research areas of common interest and developed this first edition of the Common Strategic Research Agenda (SRA) for medical radiation protection. The research topics considered necessary and most urgent for effective medical care and efficient in terms of radiation protection are summarised in five main themes: 1. Measurement and quantification in the field of medical applications of ionising radiation 2. Normal tissue reactions, radiation-induced morbidity and long-term health problems 3. Optimisation of radiation exposure and harmonisation of practices 4. Justification of the use of ionising radiation in medical practice 5. Infrastructures for quality assurance The SRA is a living document; thus comments and suggestions by all stakeholders in medical radiation protection are welcome and will be dealt with by the European Alliance for Medical Radiation Protection Research (EURAMED) established by the above-mentioned societies.

  2. Mysteries of LiF TLD response following high ionisation density irradiation: nanodosimetry and track structure theory, dose response and glow curve shapes

    PubMed Central

    Horowitz, Y.; Fuks, E.; Datz, H.; Oster, L.; Livingstone, J.; Rosenfeld, A.

    2011-01-01

    Three outstanding effects of ionisation density on the thermoluminescence (TL) mechanisms giving rise to the glow peaks of LiF:Mg,Ti (TLD-100) are currently under investigation: (1) the dependence of the heavy charged particle (HCP) relative efficiency with increasing ionisation density and the effectiveness of its modelling by track structure theory (TST), (2) the behaviour of the TL efficiency, f(D), as a function of photon energy and dose. These studies are intended to promote the development of a firm theoretical basis for the evaluation of relative TL efficiencies to assist in their application in mixed radiation fields. And (3) the shape of composite peak 5 in the glow curve for various HCP types and energies and following high-dose electron irradiation, i.e. the ratio of the intensity of peak 5a to peak 5. Peak 5a is a low-temperature satellite of peak 5 arising from electron-hole capture in a spatially correlated trapping centre/luminescent centre (TC/LC) complex that has been suggested to possess a potential as a solid-state nanodosemeter due to the preferential electron/hole population of the TC/LC at high ionisation density. It is concluded that (1) the predictions of TST are very strongly dependent on the choice of photon energy used in the determination of f(D); (2) modified TST employing calculated values of f(D) at 2 keV is in agreement with 5-MeV alpha particle experimental results for composite peak 5 but underestimates the 1.5-MeV proton relative efficiencies. Both the proton and alpha particle relative TL efficiencies of the high-temperature TL (HTTL) peaks 7 and 8 are underestimated by an order of magnitude suggesting that the HTTL efficiencies are affected by other factors in addition to radial electron dose; (3) the dose–response supralinearity of peaks 7 and 8 change rapidly with photon energy: this behaviour is explained in the framework of the unified interaction model as due to a very strong dependence on photon energy of the relative

  3. Mysteries of LiF TLD response following high ionisation density irradiation: nanodosimetry and track structure theory, dose response and glow curve shapes.

    PubMed

    Horowitz, Y; Fuks, E; Datz, H; Oster, L; Livingstone, J; Rosenfeld, A

    2011-06-01

    Three outstanding effects of ionisation density on the thermoluminescence (TL) mechanisms giving rise to the glow peaks of LiF:Mg,Ti (TLD-100) are currently under investigation: (1) the dependence of the heavy charged particle (HCP) relative efficiency with increasing ionisation density and the effectiveness of its modelling by track structure theory (TST), (2) the behaviour of the TL efficiency, f(D), as a function of photon energy and dose. These studies are intended to promote the development of a firm theoretical basis for the evaluation of relative TL efficiencies to assist in their application in mixed radiation fields. And (3) the shape of composite peak 5 in the glow curve for various HCP types and energies and following high-dose electron irradiation, i.e. the ratio of the intensity of peak 5a to peak 5. Peak 5a is a low-temperature satellite of peak 5 arising from electron-hole capture in a spatially correlated trapping centre/luminescent centre (TC/LC) complex that has been suggested to possess a potential as a solid-state nanodosemeter due to the preferential electron/hole population of the TC/LC at high ionisation density. It is concluded that (1) the predictions of TST are very strongly dependent on the choice of photon energy used in the determination of f(D); (2) modified TST employing calculated values of f(D) at 2 keV is in agreement with 5-MeV alpha particle experimental results for composite peak 5 but underestimates the 1.5-MeV proton relative efficiencies. Both the proton and alpha particle relative TL efficiencies of the high-temperature TL (HTTL) peaks 7 and 8 are underestimated by an order of magnitude suggesting that the HTTL efficiencies are affected by other factors in addition to radial electron dose; (3) the dose-response supralinearity of peaks 7 and 8 change rapidly with photon energy: this behaviour is explained in the framework of the unified interaction model as due to a very strong dependence on photon energy of the relative

  4. Annealing of GaSb Single Crystals in Ionised Hydrogen Atmosphere

    DTIC Science & Technology

    2001-01-01

    and Applications 46 of Single Crystals, Antoni Rogaski, Krzysztof Adamiec, Pawel Madejczyk, Editors, Proceedings of SPIE Vol. 4412 (2001) © 2001...1-50 hours. Hydrogen ionised by means of a deuterium lamp flew through this annealing reactor. After cooling the quartz ampoule, the carrier

  5. Identification of carbohydrates by matrix-free material-enhanced laser desorption/ionisation mass spectrometry.

    PubMed

    Hashir, Muhammad Ahsan; Stecher, Guenther; Bakry, Rania; Kasemsook, Saowapak; Blassnig, Bernhard; Feuerstein, Isabel; Abel, Gudrun; Popp, Michael; Bobleter, Ortwin; Bonn, Guenther K

    2007-01-01

    Matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF-MS) is a sensitive mass spectrometric technique which utilises acidic materials as matrices for laser energy absorption, desorption and ionisation of analytes. These matrix materials produce background signals particularly in the low-mass range and make the detection and identification of small molecules difficult and nearly impossible. To overcome this problem this paper introduces matrix-free material-enhanced laser desorption/ionisation mass spectrometry (mf-MELDI-MS) for the screening and analysis of small molecules such as carbohydrates. For this purpose, 4,4'-azo-dianiline was immobilised on silica gel enabling the absorption of laser energy sufficient for successful desorption and ionisation of low molecular weight compounds. The particle and pore sizes, the solvent system for suspension and the sample preparation procedures have been optimised. The newly synthesised MELDI material delivered excellent spectra with regard to signal-to-noise ratio and detection sensitivity. Finally, wheat straw degradation products and Salix alba L. plant extracts were analysed proving the high performance and excellent behaviour of the introduced material.

  6. Examining Pre-Service Teachers' Use of Atomic Models in Explaining Subsequent Ionisation Energy Values

    ERIC Educational Resources Information Center

    Wheeldon, Ruth

    2012-01-01

    Chemistry students' explanations of ionisation energy phenomena often involve a number of non-scientific or inappropriate ideas being used to form causality arguments. Research has attributed this to many science teachers using these ideas themselves (Tan and Taber, in "J Chem Educ" 86(5):623-629, 2009). This research extends this work by…

  7. Exploring Learners' Conceptual Resources: Singapore a Level Students' Explanations in the Topic of Ionisation Energy

    ERIC Educational Resources Information Center

    Taber, Keith S.; Tan, Kim Chwee Daniel

    2007-01-01

    This paper describes findings from a study to explore Singapore A-level (Grades 11 and 12, 16-19 yr old) students' understanding of ionisation energy, an abstract and complex topic that is featured in school chemistry courses. Previous research had reported that students in the United Kingdom commonly use alternative notions based on the perceived…

  8. Examining Pre-Service Teachers' Use of Atomic Models in Explaining Subsequent Ionisation Energy Values

    ERIC Educational Resources Information Center

    Wheeldon, Ruth

    2012-01-01

    Chemistry students' explanations of ionisation energy phenomena often involve a number of non-scientific or inappropriate ideas being used to form causality arguments. Research has attributed this to many science teachers using these ideas themselves (Tan and Taber, in "J Chem Educ" 86(5):623-629, 2009). This research extends this work by…

  9. Ionizing Radiation: The issue of radiation quality

    NASA Astrophysics Data System (ADS)

    Prise, Kevin; Schettino, Giuseppe

    Types of Ionising radiations are differentiated from each other by fundamental characteristics of their energy deposition patterns when they interact with biological materials. At the level of the DNA these non-random patterns drive differences in the yields and distributions of DNA damage patterns and specifically the production of clustered damage or complex lesions. The complex radiation fields found in space bring significant challenges for developing a mechanistic understanding of radiation effects from the perspective of radiation quality as these consist of a diverse range of particle and energy types unique to the space environment. Linear energy transfer, energy deposited per unit track length in units of keV per micron, has long been used as a comparator for different types of radiation but has limitations in that it is an average value. Difference in primary core ionizations relative to secondary delta ray ranges vary significantly with particle mass and energy leading to complex interrelationships with damage production at the cellular level. At the cellular level a greater mechanistic understanding is necessary, linking energy deposition patterns to DNA damage patterns and cellular response, to build appropriate biophysical models that are predictive for different radiation qualities and mixed field exposures. Defined studies using monoenergetic beams delivered under controlled conditions are building quantitative data sets of both initial and long term changes in cells as a basis for a great mechanistic understanding of radiation quality effects of relevance to not only space exposures but clinical application of ion-beams.

  10. Atomic data needs for X-ray spectroscopy of photo-ionised plasmas

    NASA Astrophysics Data System (ADS)

    Kaastra, Jelle S.

    2005-05-01

    High-resolution X-ray spectroscopy of Active Galactic Nuclei has become possible thanks to the launch of XMM-Newton and Chandra with their grating spectrometers, and will be explored further after the expected launch of ASTRO-E2 with its XRS detector. In several AGN the X-ray spectra show the signatures of on outflowing, photo-ionised wind. Also several X-ray binaries show a similar imprint of a photo-ionised gas. The clearest signatures are formed by the broad range of absorption lines, mostly from the ground states of a wide range of ionisation states of the abundant elements. In addition to absorption lines due to the valence electrons, the spectra show many inner-shell absorption lines. Examples are the K-shell transitions of the most abundant metal, oxygen, in the 19-23 Å band, and 2p-3d transitions of lowly ionised iron in the 15-17 Å region. These transitions have an extremely important diagnostic value, as other transitions of the same ions frequently occur in the unobservable extreme ultraviolet. Several of these inner-shell transitions, however, lack accurate experimental or theoretical wavelengths, which makes the spectral analysis complicated and ambiguous. This is even more the case for transitions from metastable levels, which can be used as density diagnostics. Finally, attention is payed to the role of atomic data in the photo-ionisation equilibrium calculations. Uncertainties in for example dielectronic recombination rates cause large uncertainties in the predicted absorption line strengths.

  11. Sensitivity to ionising radiation of lymphocytes from Huntington's chorea patients compared to controls

    SciTech Connect

    McGovern, D. ); Webb, T. )

    1982-06-01

    Blood samples were collected from 22 patients with Huntington's chorea and from 22 matched controls. Lymphocytes were separated from aliquots of each sample and cultures set up both from these and from further aliquots of whole blood. After 24 hours, half of each culture was subjected to X irradiation. Seventy-two hours later the percentages of live lymphocytes were estimated for each half of every culture and the viability ratio calculated for each sample. The lymphocytes derived from the patients with Huntington's chorea were found to be more susceptible to X irradiation than were the lymphocytes derived from controls. This was true both for whole blood and separated lymphocyte cultures. This susceptibility was found not to be the result of the main types of medication received by the patients. The small differences between viability ratios from patients and controls and the degree of overlap makes this test unsuitable for the prediction of asymptomatic carriers of the Huntington's chorea gene.

  12. Effect of low dose ionising radiation and nitric oxide on the state of animal blood system.

    PubMed

    Rodionova, N; Ganzha, O; Makovetska, L; Druzhyna, M; Muzalov, I; Mikhailenko, V

    2013-01-01

    Meta: doslidyty tryvalyj vplyv oksydu azotu ta malyh doz ionizujuchoi' radiacii' na stan systemy krovi. Materialy i metody. V eksperymenti vykorystani neinbredni samci-shhury vagoju 120–140 g. Tvaryny zaznavaly dii' riznyh chynnykiv: ingaljacii' oksydom azotu protjagom 30 dib (po 14 godyn na dobu), frakcionovanogo oprominennja malymy dozamy ionizujuchoi' radiacii' v sumarnij dozi 1,0 Gr ta i'h sumisnogo vplyvu. Doslidzhuvaly gematologichni, biohimichni ta biofizychni pokaznyky. Rezul'taty doslidzhennja. Pokazana radiozahysna dija oksydu azotu na morfofunkcional'ni pokaznyky, shho projavljalos' u reakcii' erytroi'dnogo pulu krovotvorennja i limfocytarnoi' lanky, u rivni porushennja okysnogo metabolizmu, znyzhenni vmistu atypovyh limfocytiv u peryferychnij krovi. Vysnovok. Oksyd azotu za sumisnoi' prolongovanoi' dii' z malymy dozamy ionizujuchogo vyprominjuvannja vyjavljaje radiozahysnyj efekt u systemi krovi. Kombinovana dija zaznachenyh chynnykiv, shho harakteryzujut'sja vplyvom na rizni metabolichni shljahy, pryzvodyt' do bil'sh efektyvnoi' adaptacii', nizh i'h okreme zastosuvannja.

  13. Migration and sensory changes of packaging materials caused by ionising radiation

    NASA Astrophysics Data System (ADS)

    Welle, Frank; Mauer, Alexandra; Franz, Roland

    2002-03-01

    Irradiation of packaging materials—in most cases plastics—generally lead to a formation of free radicals and ions, with secondary effects such as cross-linking as well as oxidative chain scission. These effects result in a formation of volatile radiolysis products which may induce off-odours in the polymers and may change the migration characteristics of packaging materials. Irradiation affect also polymer additives which change the specific migration behaviour of polymer additives and additive related decomposition products. Migration and sensory changes of pre-sterilised packaging materials have consequences on the quality of packaged goods and consumer's safety. Therefore, migration and sensory properties of packaging materials have specific regulations. Within this paper the effects of the formation of radiolysis products on overall migration, specific migration of food additives or radiolysis products as well as on sensory changes are discussed in view of current European food law.

  14. Kinetics of the nitrogen first negative system excitation by ionising radiation

    SciTech Connect

    Khasenov, M U

    2005-12-31

    The rate constants of N{sub 2}{sup +}(B) quenching by nitrogen and helium and of two- and three-body charge exchange of He{sub 2}{sup +} on H{sub 2}, D{sub 2}, and Kr are measured from luminescence at the 0-0 transition of the first negative system of nitrogen in mixtures of helium and nitrogen with hydrogen, krypton or deuterium excited by alpha particles emitted by {sup 210}Po . (active media)

  15. Combined effects of depleted uranium and ionising radiation on zebrafish embryos.

    PubMed

    Ng, C Y P; Pereira, S; Cheng, S H; Adam-Guillermin, C; Garnier-Laplace, J; Yu, K N

    2015-11-01

    In the environment, living organisms are exposed to a mixture of stressors, and the combined effects are deemed as multiple stressor effects. In the present work, the authors studied the multiple stressor effect in embryos of the zebrafish (Danio rerio) from simultaneous exposure to alpha particles and depleted uranium (DU) through quantification of apoptotic signals at 24 h post-fertilisation (hpf) revealed by vital dye acridine orange staining. In each set of experiments, dechorionated zebrafish embryos were divided into 4 groups, each having 10 embryos: Group (C) in which the embryos did not receive any further treatment; Group (IU) in which the embryos received an alpha-particle dose of 0.44 mGy at 5 hpf and were then exposed to 100 µg l(-1) of DU from 5 to 6 hpf; Group (I) in which the embryos received an alpha-particle dose of 0.44 mGy at 5 hpf and Group (U) in which the dechorionated embryos were exposed to 100 µg l(-1) of DU from 5 to 6 hpf. The authors confirmed that an alpha-particle dose of 0.44 mGy and a DU exposure for 1 h separately led to hormetic and toxic effects assessed by counting apoptotic signals, respectively, in the zebrafish. Interestingly, the combined exposure led to an effect more toxic than that caused by the DU exposure alone, so effectively DU changed the beneficial effect (hormesis) brought about by alpha-particle irradiation into an apparently toxic effect. This could be explained in terms of the promotion of early death of cells predisposed to spontaneous transformation by the small alpha-particle dose (i.e. hormetic effect) and the postponement of cell death upon DU exposure.

  16. Electron impact ionisation of encapsulated 99mTc@C 60 and 99mTc@C 70

    NASA Astrophysics Data System (ADS)

    Đustebek, J. B.; Đorđević, V. R.; Cvetićanin, J. M.; Veličković, S. R.; Veljković, M. V.; Nešković, O. M.; Rakočević, Z. L.; Bibić, N. M.

    2010-03-01

    The present study shows simultaneous surface ionisation and electron impact ionisation during the formation and investigation of endohedral fullerenes 99mTc@C 60 and 99mTc@C 70. The endohedral fullerenes were generated using a mass spectrometer with a triple rhenium filament as an ion source. The ionisation energies (IE) determined were: 8.52 ± 0.25 eV for 99mTc@C 60 and 9.57 ± 0.25 eV for 99mTc@ C 70.

  17. Influence du traitement ionisant par rayonnement γ sur le pouvoir antioxydant de fractions polyphénoliques issues de substances d'origine végétale

    NASA Astrophysics Data System (ADS)

    Stuyck, S.; Connaulte, J.; Lesgards, G.; Prost, M.; Raffi, J.

    1998-04-01

    Ionizing radiation of vegetables is a cleaning up and preservation physical treatment which consists in submitting them to γ radiation, X radiation or electrons beam. This study deals with the influence of γ radiation on antioxidative effect of vegetables polyphenolic parts. In that purpose, we use a simple biological test based on erythrocytes haemolysis. Le traitement ionisant des produits végétaux est un procédé physique d'assainissement et de conservation qui consiste à les soumettre à l'action de rayonnements γ, de rayons X ou de faisceaux d'électrons. Ce travail porte sur l'étude de l'influence des rayonnements γ sur le pouvoir antioxydant de fractions polyphénoliques issues de substances d'origine végétale. Pour cela, un test biologique basé sur l'hémolyse d'érythrocytes est utilisé.

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

    NASA Astrophysics Data System (ADS)

    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.

  19. Angular distribution of electrons in multiphoton ionisation of polarised Lithium atoms

    NASA Astrophysics Data System (ADS)

    Klimova, Yu. A.; Marmo, S. I.; Meremianin, A. V.

    2013-09-01

    The asymmetry of the angular distributions of photoelectrons in the photoionisation of polarised alkali atoms is investigated. The general formulas for the amplitude of the multiphoton ionisation of np-states are given. In these formulas the dynamical and kinematical factors are explicitly separated. Our calculations within Fues model potential approach demonstrate that, under the experimental conditions essentially similar to those employed in [M. Schuricke, Ganjun Zhu, J. Steinmann, K. Simeonidis, I. Ivanov, A. Kheifets, A.N. Grum-Grzhimailo, K. Bartschat, A. Dorn, J. Ullrich, Phys. Rev. A 83 (2011) 023413(11)], the relative magnitude of the linear magnetic dichroism in three-photon ionisation of Li can be as large as 30%.

  20. Electrospray ionisation-cleavable tandem nucleic acid mass tag–peptide nucleic acid conjugates: synthesis and applications to quantitative genomic analysis using electrospray ionisation-MS/MS

    PubMed Central

    Thompson, Andrew; Prescott, Mark; Chelebi, Noorhan; Smith, John; Brown, Tom; Schmidt, Günter

    2007-01-01

    The synthesis and characterization of isotopomer tandem nucleic acid mass tag–peptide nucleic acid (TNT–PNA) conjugates is described along with their use as electrospray ionisation-cleavable (ESI-Cleavable) hybridization probes for the detection and quantification of target DNA sequences by electrospray ionisation tandem mass spectrometry (ESI-MS/MS). ESI-cleavable peptide TNT isotopomers were introduced into PNA oligonucleotide sequences in a total synthesis approach. These conjugates were evaluated as hybridization probes for the detection and quantification of immobilized synthetic target DNAs using ESI-MS/MS. In these experiments, the PNA portion of the conjugate acts as a hybridization probe, whereas the peptide TNT is released in a collision-based process during the ionization of the probe conjugate in the electrospray ion source. The cleaved TNT acts as a uniquely resolvable marker to identify and quantify a unique target DNA sequence. The method should be applicable to a wide variety of assays requiring highly multiplexed, quantitative DNA/RNA analysis, including gene expression monitoring, genetic profiling and the detection of pathogens. PMID:17259215

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

    NASA Astrophysics Data System (ADS)

    Gordienko, A. V.; Mavritskii, O. B.; Egorov, A. N.; Pechenkin, A. A.; Savchenkov, D. V.

    2014-12-01

    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.

  2. Migration to new ampoule types for the NPL secondary standard ionisation chambers.

    PubMed

    Baker, M; Fenwick, A; Ferreira, K; Keightley, J; Johansson, L; Collins, S

    2014-05-01

    As the pre-calibrated sample containers used for activity assay in the two NPL secondary standards ionisation chambers are being phased out, suitable replacements have been identified. Characterisation checks have been carried out on the new ISO ampoules and a long-term recalibration schedule has been devised. Around 40 calibration factors have been determined so far and comparison of ion chamber responses for the two ampoule types showed variations of up to 7% for low energy photon emitting radionuclides.

  3. Ab-initio surface hopping and multiphoton ionisation study of the photodissociation dynamics of CS2

    NASA Astrophysics Data System (ADS)

    Bellshaw, Darren; Horke, Daniel A.; Smith, Adam D.; Watts, Hannah M.; Jager, Edward; Springate, Emma; Alexander, Oliver; Cacho, Cephise; Chapman, Richard T.; Kirrander, Adam; Minns, Russell S.

    2017-09-01

    New ab initio surface hopping simulations of the excited state dynamics of CS2 including spin-orbit coupling are compared to new experimental measurements using a multiphoton ionisation probe in a photoelectron spectroscopy experiment. The calculations highlight the importance of the triplet states even in the very early time dynamics of the dissociation process and allow us to unravel the signatures in the experimental spectrum, linking the observed changes to both electronic and nuclear degrees of freedom within the molecule.

  4. Changes in plasma characteristics caused by easily ionisable elements in hollow cathode discharge emission spectrography.

    PubMed

    Szilvássy-Vámos, Z; Gyódrfi-Buzási, A; Pásztor, Z

    1991-11-01

    The effect of several concomitant easily ionisable elements (EIE's), Li, Na, K, Rb and Cs on the line intensity of Sr II (first ionised state) and Al I and He I (atomic states) has been studied by atomic emission spectrometry (AES) hollow cathode (HCD) analysis. The spectral line intensities emitted by Sr II, Al I and He I have been measured while varying the volume of the EIE's concentrations, ranging from 0.1 mg ml to 10 mg ml. In the presence of EIE's at higher concentrations than 0.5% a considerable decrease of the line intensities of Sr II at 430.54 nm and 407.71 nm was observed, together with a gradual decrease in the line intensities of both Al I 494.40 nm and 396.15 nm, and He I 412.1 nm. It is demonstrated in the present experiments with a water-cooled HCD source that interference effects caused by EIE's are observed when the ratio of the number of gas atoms (n(g)) and atoms with low ionisation energy (n(a))n(g)/n(a)is lower than 10(12).

  5. Examining Pre-Service Teachers' Use of Atomic Models in Explaining Subsequent Ionisation Energy Values

    NASA Astrophysics Data System (ADS)

    Wheeldon, Ruth

    2012-06-01

    Chemistry students' explanations of ionisation energy phenomena often involve a number of non-scientific or inappropriate ideas being used to form causality arguments. Research has attributed this to many science teachers using these ideas themselves (Tan and Taber, in J Chem Educ 86(5):623-629, 2009). This research extends this work by considering which atomic models are used in pre-service teachers' explanations and how that relates to the causality ideas expressed. Thirty-one pre-service teachers were interviewed. Each was asked to describe and explain four different atomic representations (Rutherford, Electron cloud micrograph, Bohr and Schrödinger types) in as much detail as they could. They also provided an explanation for the subsequent ionisation energy values for an oxygen atom and identified which representations were helpful in explaining the values. Significantly, when pre-service teachers only used Bohr type representations, they did not use repelling electron ideas in their explanations. However, arguments that were based on electron-electron repulsion used features from Schrödinger type atoms. These findings suggest that many pre-service teachers need to develop their atomic modelling skills so that they select and use models more expertly and that subsequent ionisation explanations offer a context in which to explore different atomic models' limitations and their deployment as explanatory resources.

  6. Is copper-silver ionisation safe and effective in controlling legionella?

    PubMed

    Cachafeiro, S Perez; Naveira, I Mato; García, I González

    2007-11-01

    Copper-silver ionisation is gaining popularity worldwide as a water disinfection method. We review the literature that supports the effectiveness and safety of the copper-silver ionisation pertaining to legionella control in water distribution systems. A search between January 1997 and January 2007 was conducted in relevant health databases: Medline, Embase, NHS CRD, Cochrane Library Plus, Web of Knowledge, IME (Spanish Medical Index) and IBECS (Health Sciences Bibliographic Index). Ten published studies were selected according to inclusion and exclusion criteria previously established; most of these were experimental. Legionella levels decrease with the application of any of the procedures used in these studies and the procedures can be combined to obtain better outcomes. No studies containing an economic evaluation were found. We conclude that copper-silver ionisation is an effective method to control legionella, bearing in mind that eradication cannot be achieved by any method in isolation. Maintaining high temperatures in the water system can maximise effectiveness of the method. Copper-silver appears to be safe, as long as ion levels are monitored and kept within international recommended levels. More studies with concurrent control group, long follow-up and economic evaluation are required to properly assess this procedure.

  7. A Carbon Nano Tube electron impact ionisation source for low-power, compact spacecraft mass spectrometers

    NASA Astrophysics Data System (ADS)

    Sheridan, S.; Bardwell, M. W.; Morse, A. D.; Morgan, G. H.

    2012-04-01

    A novel ionisation source which uses commercially available Carbon Nano Tube devices is demonstrated as a replacement for a filament based ionisation source in an ion trap mass spectrometer. The carbon nanotube ion source electron emission was characterised and exhibited typical emission of 30 ± 1.7 μA with an applied voltage differential of 300 V between the carbon nanotube tips and the extraction grid. The ion source was tested for longevity and operated under a condition of continuous emission for a period of 44 h; there was an observed reduction in emission current of 26.5% during operation. Spectra were generated by installing the ion source into a Finnigan Mat ITD700 ion trap mass spectrometer; the spectra recorded showed all of the characteristic m/z peaks from m/z 69 to m/z 219. Perfluorotributylamine spectra were collected and averaged contiguously for a period of 48 h with no significant signal loss or peak mass allocation shift. The low power requirements and low mass of this novel ionisation source are considered be of great value to future space missions where mass spectrometric technology will be employed.

  8. Variable filtered photographic film as a radiation detector for environmental radiation monitoring

    NASA Astrophysics Data System (ADS)

    Majid, Zafri Azran Abdul; Junet, Laila Kalidah; Hazali, Norazlanshah; Abdullah, Abdul Adam; Hanafiah, Megat Ahmad Kamal Megat

    2013-05-01

    Environmental radiation is an ionising radiation that present in the natural environment which mostly originates from cosmic rays and radionuclide agents in the environment. This may lead the population to be exposed to the radiation. Therefore, the environmental radiation needs to be observed cautiously to minimize the impact of radiation. However, there is no specific or proper monitoring device that provides an outdoor environmental radiation monitoring. Hence, a new outdoor environmental radiation monitoring device was developed. A photographic film has been chosen as a dosimeter. The purpose of this study was to prove the covered photographic film attached with variable filter can be used to develop environmental radiation monitoring device to detect the ionising radiation. The filter used was variable thickness of plastic, aluminium (Al) and lead (Pb). The result from the study showed that the mean optical density (OD) values for medium speed film are in the range 0.41 to 0.73, and for fast speed film the OD values are in the range 0.51 to 1.35. The OD values decreased when the filter was attached. This has proven that the photographic film can be used to detect radiation and fast speed film was more sensitive compared to medium speed film.

  9. Ionizing radiations in pregnancy and teratogenesis: a review of literature.

    PubMed

    De Santis, M; Di Gianantonio, E; Straface, G; Cavaliere, A F; Caruso, A; Schiavon, F; Berletti, R; Clementi, M

    2005-01-01

    The present paper is a review of the data available in the literature concerning the prenatal exposure to radiation evaluating the reported teratogenic effect. We have particularly focused on the fetal effects of maternal ionising radiation exposure, both diagnostic and occupational, particularly in terms of congenital anomalies and birth weight. Ionising radiation represents a possible teratogen for the fetus, but this risk has been found to be dependent on the dosage and the effects correlatable to the gestational age at exposure. Recently, of particularly note is the fact that maternal thyroid exposure to diagnostic radiation has been associated with a slight reduction in the birth weight. Inadvertent exposure from diagnostic procedures in pregnancy doesn't usually increase the natural risk of congenital anomalies but creates a considerable state of maternal anxiety. Diagnostic radiological procedures should be avoided in pregnant women unless the information cannot be obtained by other techniques.

  10. The cytoplasm as a radiation target: an in silico study of microbeam cell irradiation.

    PubMed

    Byrne, H L; Domanova, W; McNamara, A L; Incerti, S; Kuncic, Z

    2015-03-21

    We performed in silico microbeam cell irradiation modelling to quantitatively investigate ionisations resulting from soft x-ray and alpha particle microbeams targeting the cytoplasm of a realistic cell model. Our results on the spatial distribution of ionisations show that as x-rays are susceptible to scatter within a cell that can lead to ionisations in the nucleus, soft x-ray microbeams may not be suitable for investigating the DNA damage response to radiation targeting the cytoplasm alone. In contrast, ionisations from an ideal alpha microbeam are tightly confined to the cytoplasm, but a realistic alpha microbeam degrades upon interaction with components upstream of the cellular target. Thus it is difficult to completely rule out a contribution from alpha particle hits to the nucleus when investigating DNA damage response to cytoplasmic irradiation. We find that although the cytoplasm targeting efficiency of an alpha microbeam is better than that of a soft x-ray microbeam (the probability of stray alphas hitting the nucleus is 0.2% compared to 3.6% for x-rays), stray alphas produce more ionisations in the nucleus and thus have greater potential for initiating damage responses therein. Our results suggest that observed biological responses to cytoplasmic irradiation include a small component that can be attributed to stray ionisations in the nucleus resulting from the stochastic nature of particle interactions that cause out-of-beam scatter. This contribution is difficult to isolate experimentally, thus demonstrating the value of the in silico approach.

  11. Cosmic radiation in commercial aviation.

    PubMed

    Bagshaw, Michael

    2008-05-01

    This paper reviews the current knowledge of cosmic radiation and its applicability to commercial aviation. Galactic cosmic radiation emanates from outside the solar system, while occasionally a disturbance in the suns' atmosphere leads to a surge in radiation particles. Protection is provided by the suns' magnetic field, the earths' magnetic field, and the earths' atmosphere. Dose rates are dependent on the altitude, the geomagnetic latitude and the solar cycle. For occupational exposure to ionising radiation, which includes aircrew, the International Commission on Radiological Protection recommends maximum mean body effective dose limits of 20mSv/yr (averaged over 5 years, with a maximum in any 1 year of 50mSv). Radiation doses can be measured during flight or may be calculated using a computer-modelling program such as CARI, EPCARD, SIEVERT or PCAIRE. Mean ambient equivalent dose rates are consistently reported in the region of 4-5microSv/h for long-haul pilots and 1-3microSv/h for short-haul, giving an annual mean effective exposure of the order 2-3mSv for long-haul and 1-2mSv for short-haul pilots. Epidemiological studies of flight crew have not shown conclusive evidence for any increase in cancer mortality or cancer incidence directly attributable to ionising radiation exposure. Whilst there is no level of radiation exposure below which effects do not occur, current evidence indicates that the probability of airline crew or passengers suffering adverse health effects as a result of exposure to cosmic radiation is very low.

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

    PubMed

    Gallastegi, Mara; Guxens, Mònica; Jiménez-Zabala, Ana; Calvente, Irene; Fernández, Marta; Birks, Laura; Struchen, Benjamin; Vrijheid, Martine; Estarlich, Marisa; Fernández, Mariana F; Torrent, Maties; Ballester, Ferrán; Aurrekoetxea, Juan J; Ibarluzea, Jesús; Guerra, David; González, Julián; Röösli, Martin; Santa-Marina, Loreto

    2016-02-18

    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. Indirect (proximity to emission sources, questionnaires on sources use and geospatial propagation models) and direct methods (spot and fixed longer-term measurements and personal measurements) were conducted in order to assess exposure levels of study participants aged between 7 and 18 years old. The methodology used varies depending on the frequency of the EMF-NIR and the environment (homes, schools and parks). Questionnaires assessed the use of sources contributing both to Extremely Low Frequency (ELF) and Radiofrequency (RF) exposure levels. Geospatial propagation models (NISMap) are implemented and validated for environmental outdoor sources of RFs using spot measurements. Spot and fixed longer-term ELF and RF measurements were done in the environments where children spend most of the time. Moreover, personal measurements were taken in order to assess individual exposure to RF. The exposure data are used to explore their relationships with proximity and/or use of EMF-NIR sources. Characterisation of the EMF-NIR exposure by this combination of methods is intended to overcome problems encountered in other research. The assessment of exposure of INMA cohort children and adolescents living in different regions of Spain to the full frequency range of EMF-NIR extends the characterisation of environmental exposures in this cohort. Together with other data obtained in the project, on socioeconomic and family characteristics and development of the children and adolescents, this will enable to evaluate the complex

  13. KINETIC SIMULATIONS OF THERMOLUMINESCENCE DOSE RESPONSE: LONG OVERDUE CONFRONTATION WITH THE EFFECTS OF IONISATION DENSITY.

    PubMed

    Horowitz, Y S; Eliyahu, I; Oster, L

    2016-12-01

    The reader will time-travel through almost seven decades of kinetic models and mathematical simulations of thermoluminescence (TL) characteristics based on the band-gap theory of the solid state. From post-World-War II, ideas concerning electron trapping mechanisms to the highly idealised one trap-one recombination (OTOR) model first elaborated in 1956 but still in 'high gear' today. The review caresses but purposely avoids in-depth discussion of the endless stream of papers discussing the intricacies of glow peak shapes arising from first-order, second-order, mixed-order and general-order kinetics predominantly based on non-interacting systems, and then on to the more physically realistic scenarios that have attempted to analyse complex systems involving ever greater numbers of interacting trapping centres, luminescent centres and non-luminescent centres. The review emphasises the difficulty the band-gap models have in the simulation of dose response linear/supralinear behaviour and especially the dependence of the supralinearity on ionisation density. The significance of the non-observation of filling-rate supralinearity in the absorption stage is emphasised since it removes from consideration the possibility of TL supralinearity arising from irradiation stage supralinearity. The importance of the simultaneous action of both localised and delocalised transitions has gradually penetrated the mindset of the community of kinetic researchers, but most simulations have concentrated on the shape of glow peaks and the extraction of the glow peak parameters, E (the thermal activation energy) and s (the attempt-to-escape frequency). The simulation of linear/supralinear dose response and its dependence on ionisation density have been largely avoided until recently due to the fundamental schism between the effects of ionisation density and some basic assumptions of the band-gap model. The review finishes with an in-depth presentation and discussion of the most recent

  14. Monte Carlo configuration interaction applied to multipole moments, ionisation energies and electron affinities.

    PubMed

    Coe, Jeremy P; Taylor, Daniel J; Paterson, Martin J

    2013-05-15

    The method of Monte Carlo configuration interaction (MCCI) (Greer, J. Chem. Phys. 1995a, 103, 1821; Tong, Nolan, Cheng, and Greer, Comp. Phys. Comm. 2000, 142, 132) is applied to the calculation of multipole moments. We look at the ground and excited state dipole moments in carbon monoxide. We then consider the dipole of NO, the quadrupole of N2 and of BH. An octupole of methane is also calculated. We consider experimental geometries and also stretched bonds. We show that these nonvariational quantities may be found to relatively good accuracy when compared with full configuration interaction results, yet using only a small fraction of the full configuration interaction space. MCCI results in the aug-cc-pVDZ basis are seen to generally have reasonably good agreement with experiment. We also investigate the performance of MCCI when applied to ionisation energies and electron affinities of atoms in an aug-cc-pVQZ basis. We compare the MCCI results with full configuration interaction quantum Monte Carlo (Booth and Alavi, J. Chem. Phys. 2010, 132, 174104; Cleland, Booth, and Alavi, J. Chem. Phys. 2011, 134, 024112) and "exact" nonrelativistic results (Booth and Alavi, J. Chem. Phys. 2010, 132, 174104; Cleland, Booth, and Alavi, J. Chem. Phys. 2011, 134, 024112). We show that MCCI could be a useful alternative for the calculation of atomic ionisation energies however electron affinities appear much more challenging for MCCI. Due to the small magnitude of the electron affinities their percentage errors can be high, but with regards to absolute errors MCCI performs similarly for ionisation energies and electron affinities.

  15. IFU Spectroscopy of Southern Planetary Nebulae V: Low-Ionisation Structures

    NASA Astrophysics Data System (ADS)

    Ali, A.; Dopita, M. A.

    2017-08-01

    In this fifth paper of the series, we examine the spectroscopy and morphology of four southern Galactic planetary nebulae Hen 2-141, NGC 5307, IC 2553, and PB 6 using new integral field spectroscopy data. The morphologies and ionisation structures of the sample are given as a set of emission-line maps. In addition, the physical conditions, chemical compositions, and kinematical characteristics of these objects are derived. The results show that PB 6 and Hen 2-141 are of very high excitation classes and IC 2553 and NGC 5307 are mid to high excitation objects. The elemental abundances reveal that PB 6 is of Type I, Hen 2-141 and IC 2553 are of Type IIa, and NGC 5307 is of Type IIb/III. The observations unveil the presence of well-defined low-ionisation structures or `knots' in all objects. The diagnostic diagrams reveal that the excitation mechanism of these knots is probably by photoionisation of dense material by the nebular central stars. The physical analysis of six of these knots show no significant differences with their surrounding nebular gas, except their lower electron densities. In spite of the enhancement of the low-ionisation emission lines of these knots, their chemical abundances are nearly comparable to their surrounding nebulae, with the exception of perhaps slightly higher nitrogen abundances in the NGC 5307 knots. The integrated spectrum of IC 2553 reveals that nearly all key lines that have led researchers to characterise its central star as a weak-emission line star type are in fact of nebular origin.

  16. Impact ionisation spectra from hypervelocity impacts using aliphatic poly(methyl methacrylate) microparticle projectiles.

    PubMed

    Burchell, Mark J; Armes, Steven P

    2011-02-28

    We report impact ionisation spectra from spherical poly(methyl methacrylate) (PMMA) microparticles of 724 nm diameter impacting a rhodium target. These projectiles were coated with an ultrathin (~11 nm) overlayer of polypyrrole, an electrically conducting organic polymer; this enabled the accumulation of sufficient surface charge to allow electrostatic acceleration up to speeds of 4 to 8 km s(-1) using a high-voltage Van de Graaff instrument. A grid above the target (held at 3.33 kV cm(-1) with respect to the target) accelerated the cations that were generated during the hypervelocity impacts, and these ions then drifted to a charge detector. By measuring the collected charge vs. time and assuming only single ionisation events, time-of-flight mass spectra were obtained. Strong signals were observed for cationic species with ions of m/z 41, 65 and 115. There were also minor contributions from cations with masses ranging from m/z 29 to 142. The three major signals are assigned to fragment ions (C(3)H(5)(+), C(4)H(5)O(+)/C(5)H(9)(+) and C(6)H(11)O(2)(+)) which are known to be associated with the decomposition of PMMA. These impact ionisation spectra differ significantly from those reported earlier using polystyrene (PS) microparticles. The aliphatic PMMA microparticles generate small (m/z <100) fragment ions more readily at lower speeds than the predominantly aromatic PS microparticles, where speeds of at least 10 km s(-1) are typically required for substantial yields of low-mass fragment ions. This correlates well with the well-known greater chemical and thermal fragility of PMMA compared to PS. The PMMA microparticles should prove useful synthetic mimics for aliphatic carbonaceous micrometeorites. Copyright © 2011 John Wiley & Sons, Ltd.

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

    SciTech Connect

    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.

  18. Liquid chromatography with electrospray ionisation mass spectrometric detection of phenolic compounds from Olea europaea.

    PubMed

    Ryan, D; Robards, K; Prenzler, P; Jardine, D; Herlt, T; Antolovich, M

    1999-09-10

    The results demonstrate the potential of electrospray ionisation mass spectrometry for the specific detection of phenolic species in olives. Phenolic compounds were detected with greater sensitivity in the negative ion mode, but results from positive and negative ion modes were complementary with the positive ion mode showing structurally significant fragments. This is demonstrated by the identification of oleuropein and isomers of verbascoside. The structure of the latter were confirmed by retention, mass spectral and nuclear magnetic resonance data. These isomers have not previously been reported in olive.

  19. The WISSH quasars project. I. Powerful ionised outflows in hyper-luminous quasars

    NASA Astrophysics Data System (ADS)

    Bischetti, M.; Piconcelli, E.; Vietri, G.; Bongiorno, A.; Fiore, F.; Sani, E.; Marconi, A.; Duras, F.; Zappacosta, L.; Brusa, M.; Comastri, A.; Cresci, G.; Feruglio, C.; Giallongo, E.; La Franca, F.; Mainieri, V.; Mannucci, F.; Martocchia, S.; Ricci, F.; Schneider, R.; Testa, V.; Vignali, C.

    2017-02-01

    Models and observations suggest that both the power and effects of AGN feedback should be maximised in hyper-luminous (LBol > 1047 erg s-1) quasars, i.e. objects at the brightest end of the AGN luminosity function. In this paper, we present the first results of a multiwavelength observing programme, focusing on a sample of WISE/SDSS selected hyper-luminous (WISSH) broad-line quasars at z ≈ 1.5-5. The WISSH quasars project has been designed to reveal the most energetic AGN-driven outflows, estimate their occurrence at the peak of quasar activity, and extend the study of correlations between outflows and nuclear properties up to poorly investigated, extreme AGN luminosities, i.e. LBol 1047 - 1048 erg s-1. We present near-infrared, long-slit LBT/LUCI1 spectroscopy of five WISSH quasars at z ≈ 2.3 - 3.5, showing prominent [OIII] emission lines with broad (FWHM 1200-2200 km s-1) and skewed profiles. The luminosities of these broad [OIII] wings are the highest measured so far, with L[OIII]broad ≳ 5 × 1044 erg s-1, and reveal the presence of powerful ionised outflows with associated mass outflow rates Ṁ ≳ 1700M⊙ yr-1 and kinetic powers Ėkin ≳ 1045 erg s-1. Although these estimates are affected by large uncertainties because of the use of [OIII] as a tracer of ionised outflows and the very basic outflow model adopted here, these results suggest that in our hyper-luminous targets the AGN is highly efficient at pushing large amounts of ionised gas outwards. Furthermore, the mechanical outflow luminosities measured for WISSH quasars correspond to higher percentages ( 1-3%) of LBol than those derived for AGN with lower LBol. Our targets host very massive (MBH ≳ 2 × 109M⊙) black holes that are still accreting at a high rate (i.e. a factor of 0.4-3 of the Eddington limit). These findings clearly demonstrate that WISSH quasars offer the opportunity to probe the extreme end of both luminosity and supermassive black holes (SMBH) mass functions and revealing

  20. Forensic applications of desorption electrospray ionisation mass spectrometry (DESI-MS).

    PubMed

    Morelato, Marie; Beavis, Alison; Kirkbride, Paul; Roux, Claude

    2013-03-10

    Desorption electrospray ionisation mass spectrometry (DESI-MS) is an emerging analytical technique that enables in situ mass spectrometric analysis of specimens under ambient conditions. It has been successfully applied to a large range of forensically relevant materials. This review assesses and highlights forensic applications of DESI-MS including the analysis and detection of illicit drugs, explosives, chemical warfare agents, inks and documents, fingermarks, gunshot residues and drugs of abuse in urine and plasma specimens. The minimal specimen preparation required for analysis and the sensitivity of detection achieved offer great advantages, especially in the field of forensic science. Crown Copyright © 2013. Published by Elsevier Ireland Ltd. All rights reserved.

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

    NASA Astrophysics Data System (ADS)

    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.; 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. J.; 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.; Stanley, T.; Summers, D. J.; Takahashi, M.; Tarrant, J.; Taylor, I.; Tortora, L.; Torun, Y.; Tsenov, R.; Tunnell, C. D.; Vankova, G.; Verguilov, V.; Virostek, S. P.; Vretenar, M.; Walaron, K.; Watson, S.; White, C.; Whyte, C. G.; Wilson, A.; Wisting, H.; Zisman, M. S.

    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 1.2-2.3 π mm-rad horizontally and 0.6-1.0 π 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.

  2. Derivatisation and gas chromatography-chemical ionisation mass spectrometry of selected synthetic and natural endocrine disruptive chemicals.

    PubMed

    Lerch, Oliver; Zinn, Peter

    2003-03-28

    Methods for ultra trace detection of endocrine disruptive chemicals (EDCs) are needed because of their low levels of impact. Twenty-one EDCs were selected, including 17beta-estradiol, 17alpha-ethinylestradiol, 17beta-testosterone and bisphenol A. Derivatisation with eight different fluorine containing compounds was examined. All EDCs could be derivatised automatedly (autosampler) with heptafluorobutyric acid (HFB) anhydride and trifluoroacetic acid (TFA) anhydride, respectively. The detection of these HFB and TFA derivatives in different chemical ionisation modes was studied. Fourteen different reagent gases, including methane, ammonia, acetone and water, were tested with the HFB and TFA derivatives in the negative chemical ionisation mode. Furthermore both types of derivatives were measured in positive chemical ionisation mode. Methane or water provide a good detection of all 21 TFA derivatives and create mass spectra with few fragmentation and characteristic mass peaks. This could serve as a basis for tandem or multiple mass spectrometric measurements.

  3. Using photo-ionisation models to derive carbon and oxygen gas-phase abundances in the rest UV

    NASA Astrophysics Data System (ADS)

    Pérez-Montero, Enrique; Amorín, Ricardo

    2017-01-01

    We present a new method to derive oxygen and carbon abundances using the ultraviolet (UV) lines emitted by the gas-phase ionised by massive stars. The method is based on the comparison of the nebular emission-line ratios with those predicted by a large grid of photo-ionisation models. Given the large dispersion in the O/H - C/O plane, our method firstly fixes C/O using ratios of appropriate emission lines and, in a second step, calculates O/H and the ionisation parameter from carbon lines in the UV. We find abundances totally consistent with those provided by the direct method when we apply this method to a sample of objects with an empirical determination of the electron temperature using optical emission lines. The proposed methodology appears as a powerful tool for systematic studies of nebular abundances in star-forming galaxies at high redshift.

  4. A rapid ex vivo tissue model for optimising drug detection and ionisation in MALDI imaging studies.

    PubMed

    Huber, K; Aichler, M; Sun, N; Buck, A; Li, Z; Fernandez, I E; Hauck, S M; Zitzelsberger, H; Eickelberg, O; Janssen, K P; Keller, U; Walch, A

    2014-10-01

    The aim of this study was to establish an ex vivo model for a faster optimisation of sample preparation procedures, for example matrix choice, in matrix-assisted laser desorption/ionisation (MALDI) drug imaging studies. The ionisation properties of four drugs, afatinib, erlotinib, irinotecan and pirfenidone, were determined in an ex vivo tissue experiment by spotting decreasing dilution series onto liver sections. Hereby, the drug signals were distinctly detectable using different matrix compounds, which allowed the selection of the optimal matrix for each drug. The analysis of afatinib and erlotinib yielded high drug signals with α-cyano-4-hydroxycinnamic acid matrix, whereas 2,3-dihydroxybenzoic acid was identified as optimal matrix for irinotecan and pirfenidone detection. Our method was validated by a MALDI drug imaging approach of in vivo treated mouse tissue resulting in corresponding findings, indicating the spotting method as an appropriate approach to determine the matrix of choice. The present study shows the accordance between the detection of ex vivo spotted drugs and in vivo administered drugs by MALDI-TOF and MALDI-FT-ICR imaging, which has not been demonstrated so far. Our data suggest the ex vivo tissue spotting method as an easy and reliable model to optimise MALDI imaging measurements and to predict drug detection in tissue sections derived from treated mice prior to the recruitment of laboratory animals, which helps to save animals, time and costs.

  5. An experimental and theoretical study of core-valence double ionisation of acetaldehyde (ethanal).

    PubMed

    Zagorodskikh, S; Vapa, M; Vahtras, O; Zhaunerchyk, V; Mucke, M; Eland, J H D; Squibb, R J; Linusson, P; Jänkälä, K; Ågren, H; Feifel, R

    2016-01-28

    Core-valence double ionisation spectra of acetaldehyde (ethanal) are presented at photon energies above the carbon and oxygen 1s ionisation edges, measured by a versatile multi-electron coincidence spectroscopy technique. We use this molecule as a testbed for analyzing core-valence spectra by means of quantum chemical calculations of transition energies. These theoretical approaches range from two simple models, one based on orbital energies corrected by core valence interaction and one based on the equivalent core approximation, to a systematic series of quantum chemical electronic structure methods of increasing sophistication. The two simple models are found to provide a fast orbital interpretation of the spectra, in particular in the low energy parts, while the coverage of the full spectrum is best fulfilled by correlated models. CASPT2 is the most sophisticated model applied, but considering precision as well as computational costs, the single and double excitation configuration interaction model seems to provide the best option to analyze core-valence double hole spectra.

  6. Gas chromatography with diode array detection in series with flame ionisation detection.

    PubMed

    Gras, Ronda; Luong, Jim; Shellie, Robert A

    2017-06-02

    We introduce a gas chromatography detection approach that uses diode array detection operated in series with flame ionisation detection and demonstrate the utility of the detection approach for determination of volatile organic compounds. Diode array detection brings ultraviolet - visible spectroscopy (over a range of 190-640nm) onto the capillary gas chromatography time-scale, where average peak widths of analytes are on the order of 3-5s. The non-destructive nature of the diode array detector affords serially-coupled flame ionisation detection. This arrangement delivers near-simultaneous selective and universal detection without incurring additional analytical time, and without recourse to column flow splitting. The hyphenated technique is shown to be effective for chromatographic applications spanning an equivalent volatility range from C1 to C7n-paraffin hydrocarbons. The approach introduced herein provides increased sensitivity and selectivity for classes of compounds amenable to electronic spectroscopy such as alkenes, dienes, sulfurs, and aromatic compounds. The approach is demonstrated for direct measurement of carbon disulfide in work place atmospheres with a detection limit of 93pg on column and for the direct measurement of 1,3-butadiene in hydrocarbon matrices and ambient air with a detection of 73pg on column, each in less than 5min. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Measuring technique for thermal ionisation mass spectrometry of human tracer kinetic study with stable cerium isotopes.

    PubMed

    Keiser, Teresa; Höllriegl, Vera; Giussani, Augusto; Oeh, Uwe

    2011-06-01

    Thermal ionisation mass spectrometry (TIMS) method has been developed for the simultaneous detection of different cerium isotopes in biological samples (i.e., blood and urine) at very low concentrations. The work has been done in the frame of a biokinetic study, where different stable cerium isotopes have been administered orally and intravenously as tracers to the human body. In order to develop an appropriate detection method for the tracers in the biological samples, an optimum sample preparation technique has been set and adapted to the specific requirements of the analysis technique used, i.e., TIMS. For sample evaporation and ionisation, the double tantalum filament technique showed the best results. The ions produced were simultaneously collected on a secondary electron multiplier so that the isotopic ratios of the cerium isotopes in the biological samples could be measured. The technique has been optimised for the determination of cerium down to 1 ng loaded on the evaporation filament corresponding to cerium concentrations of down to 1 ng ml(-1) in the blood or urine samples. It has been shown that the technique is reliable in application and enables studies on cerium metabolism and biokinetics in humans without employing radioactive tracers.

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

    NASA Astrophysics Data System (ADS)

    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.

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

    SciTech Connect

    Gordienko, A V; Mavritskii, O B; Egorov, A N; Pechenkin, A A; Savchenkov, D V

    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)

  10. Plasma formation on a metal surface under combined action of laser and microwave radiation

    SciTech Connect

    Gavrilyuk, A P; Shaparev, N Ya

    2013-10-31

    By means of numerical modelling of the combined effect of laser (1.06 mm) and microwave (10{sup 10} – 10{sup 13} s{sup -1}) radiation on the aluminium surface in vacuum it is shown that the additional action of microwave radiation with the frequency 10{sup 12} s{sup -1} provides complete ionisation of the metal vapour (for the values of laser radiation duration and intensity used in the calculations), while in the absence of microwave radiation the vapour remains weakly ionised. The mathematical model used accounts for the processes, occurring in the condensed phase (heat conduction, melting), the evaporation and the kinetic processes in the resulting vapour. (interaction of laser radiation with matter. laser plasma)

  11. Determination of the health hazards due to background radiation sources in the city of Adapazari, Northwestern Turkey.

    PubMed

    Kapdan, Enis; Altinsoy, Nesrin; Karahan, Gursel; Taskin, Halim

    2011-03-01

    Human body is exposed to ionising radiations both internally and externally by mainly high-energy cosmic ray particles incident on the earth's atmosphere and radioactive nuclides that originated in the earth's crust. The main objective of this study is to assess the health hazards due to environmental radiation sources in the city of Adapazari, one of the most important industrial cities of the country, Northwestern Turkey. For this purpose, natural radiation sources, external terrestrial radiations, cosmic radiations, and inhalation exposures have been investigated. The annual average external terrestrial radiation doses were determined as 0.08 and 0.35 mSv at outdoor and indoor atmospheres, respectively. The annual average cosmic radiation doses were found to be 0.08 and 0.05 mSv for directly ionising photon components and neutron components, respectively. The annual average inhalation exposure doses due to radon and thoron were obtained as 1.42 and 0.19 mSv, respectively, in the region. The annual average effective dose due to natural radiation sources was determined as a total of 2.35 mSv with the predetermined ingestion radiation dose. The lifetime cancer risk due to the background ionising radiations has been determined as 0.9×10(-2) for the residents of the Adapazari city, with the average lifespan of 70 years. The results of the effective doses due to background radiation sources in the region and the worldwide averages were discussed.

  12. Dose measurements in pulsed radiation fields with commercially available measuring components.

    PubMed

    Friedrich, Sabrina; Hupe, Oliver

    2016-03-01

    Dose measurements in pulsed radiation fields with dosemeters using the counting technique are known to be inappropriate. Therefore, there is a demand for a portable device able to measure the dose in pulsed radiation fields. As a detector, ionisation chambers seem to be a good alternative. In particular, using a secondary standard ionisation chamber in combination with a reliable charge-measuring system would be a good solution. The Physikalisch-Technische Bundesanstalt (PTB) uses secondary standard ionisation chambers in combination with PTB-made measuring electronics for dose measurements at its reference fields. However, for general use, this equipment is too complex. For measurements on-site, a mobile special electronic system [Hupe, O. and Ankerhold, U. Determination of ambient and personal dose equivalent for personnel and cargo security screening. Radiat. Prot. Dosim. 121: (4), 429-437 (2006)] has been used successfully. Still, for general use, there is a need for a much simpler but a just as good solution. A measuring instrument with very good energy dependence for H*(10) is the secondary standard ionisation chamber HS01. An easy-to-use and commercially available electrometer for measuring the generated charges is the UNIDOS by PTW Freiburg. Depending on the expected dose values, the ionisation chamber used can be selected. In addition, measurements have been performed by using commercially available area dosemeters, e.g. the Mini SmartION 2120S by Thermo Scientific, using an ionisation chamber and the Szintomat 6134 A/H by Automess, using a scintillation detector. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  13. Effects of ionised or chelated water-soluble mineral mixture supplementation on growth performance, nutrient digestibility, blood characteristics, meat quality and intestinal microbiota in broilers.

    PubMed

    Upadhaya, S D; Lee, B R; Kim, I H

    2016-04-01

    An experiment was conducted to study the effects of dietary supplementation of water-soluble ionised or chelated mineral mixture on growth performance, nutrient digestibility, blood characteristics, relative organ weight, meat quality and excreta microflora in broilers. A total of 408 Arbor Acres broilers (17 birds in 8 replicate pens) were randomly allocated into one of the following three treatments: (1) Control/basal diet (CON), (2) T1 (basal diet + 0.5% ionised mineral mixture solution, pH 3.0) and (3) T2 (basal diet + 0.5% chelated mineral mixture solution, pH 3.0). The body weight gain was greater and feed conversion ratio was lower in broilers supplemented with ionised or chelated mineral liquid complex compared to CON during the grower and overall phase of the experiment. No significant effect in the concentration of Ca and P in the blood was observed in birds supplemented with ionised or chelated mineral mixture solution. No adverse effects were observed in organ weight and meat quality with ionised or chelated mineral mixture supplementation. Regarding intestinal microbiota counts there was a reduction of Escherichia coli counts in the small intestine in ionised mineral supplemented birds. In the large intestine, E. coli as well as Salmonella populations were reduced in ionised mineral supplemented birds. In conclusion, ionised or chelated minerals have partial positive effects in improving growth performance and reducing pathogenic bacteria load in the gastro-intestinal tract.

  14. Performance of radiation survey meters in X- and gamma-radiation fields.

    PubMed

    Ceklic, Sandra; Arandjic, Danijela; Zivanovic, Milos; Ciraj-Bjelac, Olivera; Lazarevic, Djordje

    2014-11-01

    The aim of this work was to investigate the different types of radiation detectors commonly used for radiation protection purposes as survey meters. The study was performed on survey meters that use different detectors as ionisation chamber, Geiger Mueller (GM) counter and scintillation detector. For each survey meter, energy dependence and angular response in X- and gamma-radiation fields was tested. The following commercially available survey meters were investigated: ionisation chambers Victoreen 451P, Babyline 31 and VA-J-15A, Geiger counter MRK-M87, 6150 AD6 and FAG FH 40F2 and scintillation counter 6150 ADB. As a source of gamma radiation, (137)Cs and (60)Co were used whereas X-ray radiation fields were generated using an X-ray unit. The radiation characteristics of the survey meters were mostly in compliance with references estimated by standard IEC 1017-2. However, some of them showed larger deviation at lower energies. GM counters exhibit strong energy dependence for low-energy photons. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  15. Perceptions of radiation safety training among interventionalists in South Africa.

    PubMed

    Rose, André; Rae, William Ian

    Exposure to ionising radiation may have deterministic and stochastic health effects, which include skin changes, chromosomal aberrations, cataracts and carcinomas. Formalised training in radiation safety and protection improves knowledge on the subject and facilitates greater compliance in safety practices. This qualitative study included 54 interventionalists (adult and paediatric cardiologists, and interventional radiologists). The participants were purposively selected and interviewed to explore their perceptions about radiation safety. A thematic analysis of the transcripts was done using a deductive and inductive approach. Findings showed participating cardiologists had less knowledge about radiation safety than participating radiologists. Cardiologists reported little or no formal training on radiation safety and did not display a culture of radiation safety. There was no consensus on how the training gap should be addressed. There is a perceived need to change and enhance the radiation safety culture among interventionists, and the participants proffered some ideas. These included the need for re-curricularisation of cardiologists' training to create awareness of radiation safety practices.

  16. PFI-ZEKE photoelectron spectrum of CH2F2, ionisation potential and ionic fragmentation appearance potentials.

    PubMed

    Forysinski, Piotr W; Zielke, Philipp; Luckhaus, David; Signorell, Ruth

    2010-04-07

    The first vibrationally resolved pulsed-field-ionisation zero-kinetic-energy (PFI-ZEKE) photoelectron spectrum of difluoromethane from its adiabatic ionisation potential (formation of the C(2v) conformer of CH(2)F(2)(+)) to the onset of the first ionic fragmentation channel is presented. Precise values for the adiabatic ionisation potential (12.7252 +/- 0.0009 eV) and the appearance potentials of the H loss product (13.065 +/- 0.003 eV) and the F loss product (14.30 +/- 0.06 eV) of the cation are reported. Ab initio harmonic calculations were performed at the MP2 level with quadruple-zeta basis sets in an attempt to assign the newly observed vibrational structure which, in its previously published low resolution form, led to numerous speculations regarding its true origin. The adiabatic ionisation potential and the fragmentation appearance potentials for the three lowest dissociation channels are also predicted in the complete basis set limit of CCSD(T) theory.

  17. Hyphenation of atmospheric pressure chemical ionisation mass spectrometry to supercritical fluid chromatography for polar car lubricant additives analysis.

    PubMed

    Lavison-Bompard, Gwenaelle; Thiébaut, Didier; Beziau, Jean-François; Carrazé, Bernadette; Valette, Pascale; Duteurtre, Xavier; Tabet, Jean-Claude

    2009-01-30

    Car lubricant additives are added to mineral or synthetic base stocks to improve viscosity and resistance to oxidation of the lubricant and to limit wear of engines. As they belong to various chemical classes and are added to a very complex medium, the base stock, their detailed chromatographic analysis is very difficult and time consuming. In a previous paper, it was demonstrated that supercritical fluid chromatography (SFC) allows the elution of common low-molecular-weight additives. Since their total resolution could not be achieved owing to the limited peak capacity of packed columns, the hyphenation of selective and informative detection methods such as atomic emission detection (AED) was required. Further to results obtained in SFC-AED, this work describes the hyphenation of SFC to atmospheric pressure chemical ionisation ion trap mass spectrometry (MS). SFC-MS hyphenation is detailed: temperature, flow rates of gas and mobile phase introduced in the source, position of the restrictor, ionisation additives and conditions of autotune are studied. Car lubricant monitoring requires negative and positive ionisation modes with or without the addition of ionisation auxiliary solvent according to the nature of additives. Moreover, when sensitivity is of major concern for a selected additive, the autotuning routine of the MS has to be performed in conditions as close as possible to analytical conditions, i.e. under subcritical conditions. Unambiguous identification and structure elucidation of several additives in formulated car lubricants are also presented.

  18. Ionisation in turbulent magnetic molecular clouds. I. Effect on density and mass-to-flux ratio structures

    NASA Astrophysics Data System (ADS)

    Bailey, Nicole D.; Basu, Shantanu; Caselli, Paola

    2017-05-01

    Context. Previous studies show that the physical structures and kinematics of a region depend significantly on the ionisation fraction. These studies have only considered these effects in non-ideal magnetohydrodynamic simulations with microturbulence. The next logical step is to explore the effects of turbulence on ionised magnetic molecular clouds and then compare model predictions with observations to assess the importance of turbulence in the dynamical evolution of molecular clouds. Aims: In this paper, we extend our previous studies of the effect of ionisation fractions on star formation to clouds that include both non-ideal magnetohydrodynamics and turbulence. We aim to quantify the importance of a treatment of the ionisation fraction in turbulent magnetised media and investigate the effect of the turbulence on shaping the clouds and filaments before star formation sets in. In particular, here we investigate how the structure, mass and width of filamentary structures depend on the amount of turbulence in ionised media and the initial mass-to-flux ratio. Methods: To determine the effects of turbulence and mass-to-flux ratio on the evolution of non-ideal magnetised clouds with varying ionisation profiles, we have run two sets of simulations. The first set assumes different initial turbulent Mach values for a fixed initial mass-to-flux ratio. The second set assumes different initial mass-to-flux ratio values for a fixed initial turbulent Mach number. Both sets explore the effect of using one of two ionisation profiles: step-like (SL) or cosmic ray only (CR-only). We compare the resulting density and mass-to-flux ratio structures both qualitatively and quantitatively via filament and core masses and filament fitting techniques (Gaussian and Plummer profiles). Results: We find that even with almost no turbulence, filamentary structure still exists although at lower density contours. Comparison of simulations shows that for turbulent Mach numbers above 2, there is

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

    PubMed

    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.

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

    PubMed

    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.

  1. Laser Ablation/Ionisation Mass Spectrometry: Sensitive and Quantitative Chemical Depth Profiling of Solid Materials.

    PubMed

    Riedo, Andreas; Grimaudo, Valentine; Moreno-García, Pavel; Neuland, Maike B; Tulej, Marek; Broekmann, Peter; Wurz, Peter

    2016-01-01

    Direct quantitative and sensitive chemical analysis of solid materials with high spatial resolution, both in lateral and vertical direction is of high importance in various fields of analytical research, ranging from in situ space research to the semiconductor industry. Accurate knowledge of the chemical composition of solid materials allows a better understanding of physical and chemical processes that formed/altered the material and allows e.g. to further improve these processes. So far, state-of-the-art techniques such as SIMS, LA-ICP-MS or GD-MS have been applied for chemical analyses in these fields of research. In this report we review the current measurement capability and the applicability of our Laser Ablation/Ionisation Mass Spectrometer (instrument name LMS) for the chemical analysis of solids with high spatial resolution. The most recent chemical analyses conducted on various solid materials, including e.g. alloys, fossils and meteorites are discussed.

  2. Ionisation density effects following optical excitation in LiF:Mg, Ti (TLD-100).

    PubMed

    Weiss, D; Horowitz, Y; Oster, L

    2007-01-01

    The TL signal following 5 eV photon excitation of previously irradiated and readout material has been studied as a function of ionisation density and various experimental parameters: (i) maximum temperature of the first readout; (ii) photon fluence; (iii) photon energy and (iv) beta ray dose. Following alpha particle irradiation, the ratio of the second-readout to first-readout TL signal, epsilon(alpha,) has been found to be 10-20 times higher than that following beta irradiation, indicative of the possibility of using the double ratio epsilon(alpha)/epsilon(beta) as a mixed-field discriminator. The beginning of an attempt to explain this unusual effect is offered in the framework of the track structure theory and kinetic modelling of the beta ray dose-response of the first and second readouts.

  3. X-ray reflection from black-hole accretion discs with a radially stratified ionisation

    NASA Astrophysics Data System (ADS)

    Svoboda, J.; Domcek, V.; Dovčiak, M.; Guainazzi, M.; Marinucci, A.

    2015-07-01

    Recent X-ray observations have suggested a very high compactness of coronae in Active Galactic Nuclei as well as in X-ray Binaries. The compactness of the source implies that the black-hole accretion disc irradiation is a strong function of radius. We will show how the X-ray spectra are modified assuming the radially stratified ionisation according to the illumination by a point-like source on the black-hole rotational axis. We will discuss how this affects the measurements of the other model parameters, such as spin and radial emissivity. We will show the application of this model to the recent XMM-Newton/NUSTAR data of an active galaxy MCG-6-30-15.

  4. Ruthenium versus platinum: interactions of anticancer metallodrugs with duplex oligonucleotides characterised by electrospray ionisation mass spectrometry.

    PubMed

    Groessl, Michael; Tsybin, Yury O; Hartinger, Christian G; Keppler, Bernhard K; Dyson, Paul J

    2010-06-01

    The binding of the ruthenium-based anticancer drug candidates KP1019, NAMI-A and RAPTA-T towards different double-stranded oligonucleotides was probed by electrospray ionisation mass spectrometry and compared with that of the widely used platinum-based chemotherapeutics cisplatin, carboplatin and oxaliplatin. It was found that the extent of adduct formation decreased in the following order: cisplatin > oxaliplatin > NAMI-A > RAPTA-T > carboplatin > KP1019. In addition to the characterisation of the adducts formed with the DNA models, the binding sites of the metallodrugs on the oligonucleotides were elucidated employing top-down tandem mass spectrometry and were found to be similar for all the metallodrugs studied, irrespective of the sequence of the oligonucleotide. A strong preference for guanine residues was established.

  5. Atmospheric pressure chemical ionisation liquid chromatography/mass spectrometry of bacteriochlorophylls from Chlorobiaceae: characteristic fragmentations.

    PubMed

    Airs, Ruth L; Keely, Brendan J

    2002-01-01

    Atmospheric pressure chemical ionisation liquid chromatography/mass spectrometry/mass spectrometry (APCI-LC/MS/MS) has been applied to the study of bacteriochlorophylls c, d, and e of phototrophic prokaryotes. Cultures of Chlorobiaceae containing bacteriochlorophyll c, d or e were examined using a high-resolution high-performance liquid chromatography (HPLC) method and APCI-LC/MS/MS employing post-column addition of formic acid. The results reveal complex distributions of bacteriochlorophyll homologues, with some closely eluting species giving isobaric protonated molecules. On-line LC/MS/MS studies reveal characteristic fragment ions for bacteriochlorophylls c, d, and e. Fragmentations involving loss of the extended alkyl substituents that are unique to bacteriochlorophylls c, d and e and their derivatives have been rationalised by studying the phaeophorbides and the results applied to the direct study of the bacteriochlorophylls.

  6. CF3(+) and CF2H(+): new reagents for n-alkane determination in chemical ionisation reaction mass spectrometry.

    PubMed

    Blake, Robert S; Ouheda, Saleh A; Evans, Corey J; Monks, Paul S

    2016-11-28

    Alkanes provide a particular analytical challenge to commonly used chemical ionisation methods such as proton-transfer from water owing to their basicity. It is demonstrated that the fluorocarbon ions CF3(+) and CF2H(+), generated from CF4, as reagents provide an effective means of detecting light n-alkanes in the range C2-C6 using direct chemical ionisation mass spectrometry. The present work assesses the applicability of the reagents in Chemical Ionisation Mass Spectrometric (CI-TOF-MS) environments with factors such as high moisture content, operating pressures of 1-10 Torr, accelerating electric fields (E/N) and long-lived intermediate complex formation. Of the commonly used chemical ionisation reagents, H3O(+) and NO(+) only react with hexane and higher while O2(+) reacts with all the target samples, but creates significant fragmentation. By contrast, CF3(+) and CF2H(+) acting together were found to produce little or no fragmentation. In dry conditions with E/N = 100 Td or higher the relative intensity of CF2H(+) to CF3(+) was mostly less than 1% but always less than 3%, making CF3(+) the main reagent ion. Using O2(+) in a parallel series of experiments, a substantially greater degree of fragmentation was observed. The detection sensitivities of the alkanes with CF3(+) and CF2H(+), while relatively low, were found to be better than those observed with O2(+). Experiments using alkane mixtures in the ppm range have shown the ionisation technique based on CF3(+) and CF2H(+) to be particularly useful for measurements of alkane/air mixtures found in polluted environments. As a demonstration of the technique's effectiveness in complex mixtures, the detection of n-alkanes in a smoker's breath is demonstrated.

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

    NASA Astrophysics Data System (ADS)

    Bannan, T.; Booth, M.; Benyezzar, M.; Bacak, A.; Alfarra, M. R. R.; Topping, D. O.; Percival, C.

    2015-12-01

    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.

  8. A photo-ionised canopy for the shock-excited Criss-Cross nebula

    NASA Astrophysics Data System (ADS)

    Temporin, S.; Weinberger, R.; Stecklum, B.

    2007-05-01

    Aims:We study a new broad, well-defined arc of optical nebulosity close to the cloud-shock interacting Criss-Cross nebula, derive the basic physical properties of the nebulosity, and revise those of the nebula, and compare both objects to simulations of cloud-shock interactions from the literature. Methods: Deep optical, partly wide-field images were used to reveal the intricate morphology and overall extent of the nebulosities. Optical spectroscopy enabled us to uncover their nature. Results: The two nebulosities are obviously physically linked, but are of different types; the Criss-Cross nebula is, as was also shown in an earlier paper, excited via a slow shock from the expanding Orion-Eridanus bubble, but the broad arc is definitely photo-ionised. The source for ionising photons appears to be hot gas in this bubble. Some results of simulations of interactions of SNRs with interstellar clouds available from the literature bear a striking resemblance to our nebulae, which appear to represent an example - unrivalled in closeness and clarity - of an early-to-medium stage in the destruction of an isolated cloud over-run by a highly evolved SNR. Thereby the Criss-Cross nebula is, when seen from the SNR, the rear disrupted part of the original, small cloud, whereas the arc is probably its still rather intact front part. Based on observations made with the Nordic Optical Telescope, operated on the island of La Palma jointly by Denmark, Finland, Iceland, Norway, and Sweden, at the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias.

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

    NASA Astrophysics Data System (ADS)

    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.

  10. Radiation hazards from horses undergoing scintigraphy using technetium-99m.

    PubMed

    Whitelock, R G

    1997-01-01

    This paper quantifies the extent of the radiation hazard to personnel from horses undergoing scintigraphy using technetium99m methylene diphosphonate (99Tcm-MDP). From the data produced it is possible to derive safe working protocols which are comfortably within the legislated limits for whole body doses as set out in the Ionising Radiations Regulations 1985. Measurements were made of the surface and environmental activities which result from individuals undergoing scintigraphic evaluation and also from urine contaminated bedding. The use of both high and low activities in the assessment of the radiation hazard to personnel and owners is considered.

  11. Assessment of radiation protection practices among radiographers in Lagos, Nigeria

    PubMed Central

    Eze, Cletus Uche; Abonyi, Livinus Chibuzo; Njoku, Jerome; Irurhe, Nicholas Kayode; Olowu, Oluwabola

    2013-01-01

    Background: Use of ionising radiation in diagnostic radiography could lead to hazards such as somatic and genetic damages. Compliance to safe work and radiation protection practices could mitigate such risks. The aim of the study was to assess the knowledge and radiation protection practices among radiographers in Lagos, Nigeria. Materials and Methods: The study was a prospective cross sectional survey. Convenience sampling technique was used to select four x-ray diagnostic centres in four tertiary hospitals in Lagos metropolis. Data were analysed with Epi- info software, version 3.5.1. Results: Average score on assessment of knowledge was 73%. Most modern radiation protection instruments were lacking in all the centres studied. Application of shielding devices such as gonad shield for protection was neglected mostly in government hospitals. Most x-ray machines were quite old and evidence of quality assurance tests performed on such machines were lacking. Conclusion: Radiographers within Lagos metropolis showed an excellent knowledge of radiation protection within the study period. Adherence to radiation protection practices among radiographers in Lagos metropolis during the period studied was, however, poor. Radiographers in Lagos, Nigeria should embrace current trends in radiation protection and make more concerted efforts to apply their knowledge in protecting themselves and patients from harmful effects of ionising radiation. PMID:24665152

  12. Biological microdosimetry based on radiation cytotoxicity data.

    PubMed

    Scott, B R; Hutt, J; Lin, Y; Padilla, M T; Gott, K M; Potter, C A

    2013-01-01

    Researchers in the field of radiation microdosimetry have attempted to explain the relative biological effectiveness (RBE) of different ionising photon radiation sources on the basis of the singly stochastic, microdose metric lineal energy y, which only addresses physical stochasticity related to energy (ε) deposition via single events in the critical targets (cell nuclei assumed here). Biological stochasticity related to variable nuclei geometries and cell orientations (relative to the incoming radiation) is usually not addressed. Here a doubly stochastic microdose metric, the single-event hit size q (=ε/T), is introduced which allows the track length T to be stochastic. The new metric is used in a plausible model of metabolic-activity-based in vitro cytotoxicity of low-dose ionising photon radiation. The cytotoxicity model has parameters E{q} (average single-event hit size with q assumed to be exponentially distributed) and E{α}, which is the average value of the cellular response parameter α. E{α} is referred to as the biological signature and it is independent of q. Only E{q} is needed for determination of RBE. The model is used to obtain biological-microdosimetry-based q spectra for 320-kV X-rays and (137)Cs gamma rays and the related RBE for cytotoxicity. The spectra are similar to published lineal energy y spectra for 200-kV X-rays and (60)Co gamma rays for 1-μm biological targets.

  13. The use of particle beam mass spectrometry for the measurement of impurities in a nabumetone drug substance, not easily amenable to atmospheric pressure ionisation techniques.

    PubMed

    Wolff, J C; Hawtin, P N; Monté, S; Balogh, M; Jones, T

    2001-01-01

    Liquid chromatography/particle beam mass spectrometry (LC/PB-MS) was used for the structural elucidation of some impurities in nabumetone as this compound poorly ionises by atmospheric pressure ionisation (API) techniques. PB-MS was optimised for nabumetone and a sensitivity study was carried out. To obtain full scan electron ionisation spectra a minimum of 100 ng of compound on column was needed. By using 20 mg/mL solutions of nabumetone, impurities at levels of about 250 ppm mass fraction relative to nabumetone could be detected. Results were compared with LC/API-MS and previous GC/MS.

  14. Radiosensitization of Aspergillus niger and Penicillium chrysogenum using basil essential oil and ionizing radiation for food decontamination.

    USDA-ARS?s Scientific Manuscript database

    The Minimum Inhibitory Concentration (MIC) of basil oil, was determined for two pathogenic fungi of rice, Aspergillus niger and Penicillium chrysogenum. The antifungal activity of the basil oil in combination with ionising radiation was then investigated to determine if basil oil caused radiosensit...

  15. Concentration and dry deposition of mercury species in arid south central New Mexico (2001-2002)

    USGS Publications Warehouse

    Caldwell, Colleen A.; Swartzendruber, Philip; Prestbo, Eric

    2006-01-01

    This research was initiated to characterize atmospheric deposition of reactive gaseous mercury (RGM), particulate mercury (HgP; <2.5 μm), and gaseous elemental mercury (Hg0) in the arid lands of south central New Mexico. Two methods were field-tested to estimate dry deposition of three mercury species. A manual speciation sampling train consisting of a KCl-coated denuder, 2.5 μm quartz fiber filters, and gold-coated quartz traps and an ion-exchange membrane (as a passive surrogate surface) were deployed concurrently over 24-h intervals for an entire year. The mean 24-h atmospheric concentration for RGM was 6.8 pg m-3 with an estimated deposition of 0.10 ng m-2h-1. The estimated deposition of mercury to the passive surrogate surface was much greater (4.0 ng m-2h-1) but demonstrated a diurnal pattern with elevated deposition from late afternoon to late evening (1400−2200; 8.0 ng m-2h-1) and lowest deposition during the night just prior to sunrise (2200−0600; 1.7 ng m-2h-1). The mean 24-h atmospheric concentrations for HgP and Hg0 were 1.52 pg m-3 and 1.59 ng m-3, respectively. Diurnal patterns were observed for RGM with atmospheric levels lowest during the night prior to sunrise (3.8 pg m-3) and greater during the afternoon and early evening (8.9 pg m-3). Discernible diurnal patterns were not observed for either HgP or Hg0. The total dry deposition of Hg was 5.9 μg m-2 year-1 with the contribution from the three species as follows:  RGM (0.88 μg m-2 year-1), HgP (0.025 μg m-2 year-1), and Hg0 (5.0 μg m-2 year-1). The annual wet deposition for total mercury throughout the same collection duration was 4.2 μg m-2 year-1, resulting in an estimated total deposition of 10.1 μg m-2 year-1 for Hg. On one sampling date, enhanced HgP (12 pg m-3) was observed due to emissions from a wildfire approximately 250 km to the east.

  16. Lower Klickitat Riparian and In-channel Habitat Restoration Project, Annual Report 2001-2002.

    SciTech Connect

    Conley, Will

    2003-10-01

    This project focuses on the lower Klickitat River and its tributaries that provide or affect salmonid habitat. The overall goal is to restore watershed health to aid recovery of salmonid stocks in the Klickitat subbasin. An emphasis is placed on restoration and protection of watersheds supporting anadromous fish production, particularly steelhead (Oncorhyncus mykiss) which are listed as 'Threatened' within the Mid-Columbia ESU. Restoration activities are aimed at restoring stream processes by removing or mitigating watershed perturbances and improving habitat conditions and water quality. In addition to steelhead, habitat improvements benefit Chinook (O. tshawytscha) and coho (O. kisutch) salmon, resident rainbow trout, and enhance habitat for many terrestrial and amphibian wildlife species. Protection activities compliment restoration efforts within the subbasin by securing refugia and preventing degradation. Since 90% of the project area is in private ownership, maximum effectiveness will be accomplished via cooperation with state, federal, tribal, and private entities. The project addresses goals and objectives presented in the Klickitat Subbasin Summary and the 1994 NWPPC Fish and Wildlife Program. Feedback from the 2000 Provincial Review process indicated a need for better information management to aid development of geographic priorities. Thus, an emphasis has been placed on database development and a review of existing information prior to pursuing more extensive implementation. Planning and design was initiated on several restoration projects. These priorities will be refined in future reports as the additional data is collected and analyzed. Tasks listed are for the April 1, 2001 to August 31, 2002 contract cycle, for which work was delayed during the summer of 2001 because the contract was not finalized until mid-August 2001. Accomplishments are provided for the September 1, 2001 to August 31, 2002 reporting period. During this reporting period, significant progress was made on acquisition and development of spatial data, monitoring of steelhead spawning, riparian revegetation, streamflow monitoring, completion of maintenance and repair work, completion of a working version of a habitat database, and completion of the Swale Creek assessment.

  17. How the Army Runs. A Senior Leader Reference Handbook, 2001-2002

    DTIC Science & Technology

    2002-01-01

    Army Food Program to include the Philip A. Connelly Award for Excellence in Food Service and the Culinary Arts Program. (d) The CIE Team. CIE is...as significantly enhanced detail (rates for specific populations, gender , etc.) to support ODSCPER decisions. Like the current systems, it will...Runs 13-48 to ensure soldiers and their families receive equal opportunity and treatment, without regard to race, color, religion, gender , or national

  18. Econ Ed & the Fed: Resources and Information for Educators, 2001-2002.

    ERIC Educational Resources Information Center

    Strahm, Sharon, Ed.

    2001-01-01

    This Fall 2001-Spring 2002 newsletter provides resources and information to educators, particularly economics, history, social studies, and business educators, throughout the western district of the Federal Reserve System. The goal of the newsletter is to highlight new Federal Reserve teaching materials and resources, including Web sites,…

  19. College of the Canyons Partnership for Excellence, Academic Year 2001-2002. Report.

    ERIC Educational Resources Information Center

    Meuschke, Daylene M.; Dixon, P. Scott; Gribbons, Barry C.

    This report, compiled by the College of the Canyons Office of Institutional Development and Technology, assesses the programs and projects of College of the Canyons as part of the Partnership for Excellence (PFE) Program. The report explains that the PFE Program is a mutual commitment by the State of California and the California Community College…

  20. Evaluation of New Canal Point Clones: 2001-2002 Harvest Season

    USDA-ARS?s Scientific Manuscript database

    Thirty replicated experiments were conducted on 9 farms (representing 7 muck and 2 sand soils) to evaluate 48 new Canal Point (CP) clones of sugarcane from the CP 94, CP 95, CP 96, and CP 97 series. Experiments compared the cane and sugar yields of the new clones, complex hybrids of Saccharum spp., ...

  1. Research and Clinical Center for Child Development Annual Report, 2001-2002.

    ERIC Educational Resources Information Center

    Chen, Shing-Jen, Ed.; Murohashi, Harumitsu, Ed.; Fujino, Yuki, Ed.

    This annual report presents several articles related to the work of the Clinical Center for Child Development at Hokkaido University in Sapporo, Japan. The articles are: (1) "The Functional Uses of Infant-Directed Speech of Fathers and Mothers: A Comparison Study" (Katsuko Niwano); (2) "Are Children 'Among the Gods'?: Parental…

  2. Hillsborough Community College, Ybor Campus Developmental Learning Community Program 2001-2002 Fall Summary.

    ERIC Educational Resources Information Center

    Gaspar, Richard F.

    This report outlines the program structures and faculty/staff roles of a developmental learning community (LC) initiative at Hillsborough Community College, Ybor Campus (Florida). The program consists of educational structures that link existing developmental courses and curriculum materials to a central theme: the importance of technology…

  3. Oxbow Conservation Area; Middle Fork John Day River, Annual Report 2001-2002.

    SciTech Connect

    Robertson, Shaun; Smith, Brent; Cochran, Brian

    2003-04-01

    In early 2001, the Confederated Tribes of Warm Springs, through their John Day Basin Office, concluded the acquisition of the Middle Fork Oxbow Ranch. Under a memorandum of agreement with the Bonneville Power Administration (BPA), the Tribes are required to provided BPA an 'annual written report generally describing the real property interests in the Project, HEP analyses undertaken or in progress, and management activities undertaken or in progress'. This report is to be provided to the BPA by 30 April of each year. This is the first annual report filed for the Oxbow Ranch property.

  4. Umatilla River Fish Passage Operations Program, 2001-2002 Annual Report.

    SciTech Connect

    Zimmerman, Brian C.; Duke, Bill B.

    2003-02-01

    Threemile Falls Dam (Threemile Dam), located near the town of Umatilla, Oregon is the major collection and counting point for adult salmonids returning to the Umatilla River. Returning salmon and steelhead were enumerated at Threemile Dam from August 22, 2001 to September 12, 2002. A total of 5,519 summer steelhead (Oncorhynchus mykiss); 1,146 adult, 1,158 jack, and 970 subjack fall chinook (O. tshawytscha); 22,792 adult and 80 jack coho (O. kisutch); and 5,058 adult and 188 jack spring chinook (O. tshawytscha) were counted. All fish were enumerated at the east bank facility. Of the fish counted, 261 adult and 14 jack spring chinook were hauled upstream from Threemile Dam for release. There were 5,359 summer steelhead; 622 adult, 1,041 jack and 867 subjack fall chinook; 22,513 adult and 76 jack coho; and 4,061 adult and 123 jack spring chinook either released at, or allowed to volitionally migrate past, Threemile Dam. In addition, 110 summer steelhead; 462 adult and 24 jack fall chinook; and 560 adult and 28 jack spring chinook were collected for brood. The Westland Canal juvenile facility (Westland), located near the town of Echo at rivermile (RM) 27, is the major collection point for outmigrating juvenile salmonids and steelhead kelts. The canal was open for 141 days between February 22 and July 12, 2002. During that period, fish were bypassed back to the river 134 days and were trapped 5 days. An estimated 200 pounds of juvenile fish were transported from Westland. Approximately 90% of the juveniles transported were salmonids. No steelhead kelts were hauled from Westland this year. The Threemile Dam west bank juvenile bypass was opened August 16, 2002. The bypass was run until October 31, 2001 with the exception of the period from August 29 to September 16. The bypass was reopened March 7, 2002 and ran until July 8. The juvenile trap was operated from July 8 to July 12 by the Umatilla Passage Evaluation project.

  5. Yakima/Klickitat Fisheries Project: Management, Data and Habitat, Annual Report 2001-2002.

    SciTech Connect

    Sampson, Melvin R.

    2002-03-01

    The Yakima/Klickitat Fisheries Project (YKFP or Project) is an all stock initiative that is responding to the need for scientific knowledge for rebuilding and maintaining naturally spawning anadromous fish stocks in both basins. The Yakama Nation, as the Lead Agency, in coordination with the co-managers, Washington Department of Fish and Wildlife and in cooperation with the Bonneville Power Administration, the funding agency, is pursuing this. We are testing the principles of supplementation as a means to rebuild fish populations through the use of locally adapted broodstock in an artificial production program. This concept is being utilized on the Spring Chinook within the Yakima River Basin. The coho and fall chinook programs were approved and implemented in the Yakima Basin. The coho programs principle objective is to determine if naturally spawning coho populations can be reintroduced throughout their biological range in the basin. The objective of the fall chinook program is to determine if supplementation is a viable strategy to increase fall chinook populations in the Yakima subbasin. The coho and fall chinook programs are under the three step process that was established by the Northwest Power Planning Council. The Klickitat subbasin management program is combined with the Yakima subbasin program. This contract includes the Klickitat Basin Coordinator and operational costs for the basin. The Klickitat Subbasin has separate contracts for Monitoring & Evaluation, Construction, and ultimately, Operation and Maintenance. In the Klickitat subbasin, we propose to use supplementation to increase populations of spring chinook and steelhead. This program is still in the developmental stages consistent with the three step process.

  6. SURVEILLANCE FOR DRINKING WATER-ASSOCIATED OUTBREAKS-UNITED STATES, 2001-2002

    EPA Science Inventory

    Problem/Condition: Since 1971, CDC, the U.S. Environmental Protection
    Agency (EPA), and the Council of State and Territorial Epidemiologists CSTE) have maintained a collaborative surveillance system for collecting and periodically reporting data related to occurrences and cau...

  7. Mitigation for the Construction and Operation of Libby Dam, 2001-2002 Annual Report.

    SciTech Connect

    Dunnigan, James L.; Marotz, Brian L.; DeShazer, Jay

    2003-06-01

    Libby Reservoir was created under an International Columbia River Treaty between the United States and Canada for cooperative water development of the Columbia River Basin (Columbia River Treaty 1964). Libby Reservoir inundated 109 stream miles of the mainstem Kootenai River in the United States and Canada, and 40 miles of tributary streams in the U.S. that provided habitat for spawning, juvenile rearing, and migratory passage (Figure 1). The authorized purpose of the dam is to provide power (91.5%), flood control (8.3%), and navigation and other benefits (0.2%; Storm et al. 1982). The Pacific Northwest Power Act of 1980 recognized possible conflicts stemming from hydroelectric projects in the northwest and directed Bonneville Power Administration to ''protect, mitigate, and enhance fish and wildlife to the extent affected by the development and operation of any hydroelectric project of the Columbia River and its tributaries...'' (4(h)(10)(A)). Under the Act, the Northwest Power Planning Council was created and recommendations for a comprehensive fish and wildlife program were solicited from the region's federal, state, and tribal fish and wildlife agencies. Among Montana's recommendations was the proposal that research be initiated to quantify acceptable seasonal minimum pool elevations to maintain or enhance the existing fisheries (Graham et al. 1982). Research to determine how operations of Libby Dam affect the reservoir and river fishery and to suggest ways to lessen these effects began in May, 1983. The framework for the Libby Reservoir Model (LRMOD) was completed in 1989. Development of Integrated Rule Curves (IRCs) for Libby Dam operation was completed in 1996 (Marotz et al. 1996). The Libby Reservoir Model and the IRCs continue to be refined (Marotz et al 1999). Initiation of mitigation projects such as lake rehabilitation and stream restoration began in 1996. The primary focus of the Libby Mitigation project now is to redevelop fisheries and fisheries habitat in basin streams and lakes.

  8. Evaluate Bull Trout Movements in the Tucannon and Lower Snake Rivers, 2001-2002 Annual Report.

    SciTech Connect

    Faler, Michael P.; Mendel, Glen W.; Fulton, Carl

    2003-06-01

    We collected, radio-tagged, and PIT-tagged 41 bull trout at the Tucannon River Hatchery trap from May 17, through June 14, 2002. An additional 65 bull trout were also collected and PIT tagged by June 24, at which time we ceased PIT tagging operations because water temperatures were reaching 16.0 C or higher on a regular basis. Six radio-tags were recovered shortly after tagging, and as a result, 35 remained in the river through November 30, 2002. During the month of July, radio-tagged bull trout exhibited a general upstream movement into the upper reaches of the Tucannon Subbasin. We began to observe some downstream movements of radio-tagged bull trout in mid to late September and throughout October. These movements appeared to be associated with post spawning migrations. As of November 30, radio tagged bull trout were relatively stationary, and distributed from the headwaters downstream to river mile 11.3, near Pataha Creek. None of the radio-tagged bull trout left the Tucannon Subbasin and entered the federal hydropower system on the mainstem Snake River. We conducted some initial transmission tests of submerged radio tags at depths of 25, 35, 45, and 55 ft. in Lower Monumental Pool to test our capability of detection at these depths. Equipment used included Lotek model MCFT-3A transmitters, an SRX 400 receiver, a 4 element Yagi antenna, and a Lotek ''H'' antenna. Test results indicated that depth transmission of these tags was poor; only the transmitter placed at 25 ft. was audibly detectable.

  9. Classroom Notes Plus: A Quarterly of Teaching Ideas, 2001-2002.

    ERIC Educational Resources Information Center

    Classroom Notes Plus, 2002

    2002-01-01

    This 19th issue of "Notes Plus" contains descriptions of original, unpublished teaching practices, and of adapted ideas. Under the Ideas from the Classroom section, the August 2001 issue contains the following materials: "Imitation: The Sincerest Form of Flattery" (Anna M. Parks); "Stories That Make Us Who We Are"…

  10. Redfish Lake Sockeye Salmon Captive Broodstock Rearing and Research, Annual Report 2001-2002.

    SciTech Connect

    Frost, Deborah; McAuley, W.; Maynard, Desmond

    2003-04-01

    The National Marine Fisheries Service (NMFS) Northwest Fisheries Science Center, in cooperation with the Idaho Department of Fish and Game and the Bonneville Power Administration, has established captive broodstock programs to aid recovery of Snake River sockeye salmon (Oncorhynchus nerka) listed as endangered under the U.S. Endangered Species Act (ESA). Captive broodstock and captive rearing programs are a form of artificial propagation that are emerging as an important component of restoration efforts for ESA-listed salmon populations that are at critically low numbers. Captive broodstocks, reared in captivity for the entire life cycle, couple the salmon's high fecundity with potentially high survival in protective culture to produce large numbers of juveniles in a single generation for supplementation of natural populations. The captive broodstocks discussed in this report were intended to protect the last known remnants of sockeye salmon that return to Redfish Lake in the Sawtooth Basin of Idaho at the headwaters of the Salmon River. This report addresses NMFS activities from 1 September 2001 to 31 August 2002 on the Redfish Lake sockeye salmon captive broodstock and captive rearing program. NMFS currently has broodstocks in culture from year classes 1997, 1998, 1999, 2000, and 2001 in both the captive breeding and captive rearing programs. Offspring from these programs are being returned to Idaho to aid recovery efforts for the species.

  11. The Global Youth Tobacco Survey: 2001-2002 in Riyadh region, the Kingdom of Saudi Arabia.

    PubMed

    Al-Bedah, Abdullah Mohammed; Qureshi, Naseem Akhtar

    2011-01-01

    Tobacco use is a major public health problem, and its prevalence is globally increasing, especially among children and adolescents. The Global Youth Tobacco Survey aimed to explore the epidemiological trends and risk factors of tobacco smoking among intermediate school boys in Riyadh region of the Kingdom of Saudi Arabia. A two-stage cluster sample design was used to produce a representative sample of male students from selected schools. The participants (n = 1830) self recorded their responses on the Global Youth Tobacco Survey questionnaire. Lifetime prevalence of cigarette smoking was 35%, while 13% of students currently used other tobacco products. About 16% of students currently smoked at home, and 84% of students bought cigarettes without any refusal from storekeepers. Thirty-one percent and 39% of students were exposed to secondhand tobacco smoke inside and outside the house, respectively, which was definitely or probably harmful to health as opined by 87% of participants, and 74% voiced to ban smoking from public places. Among current smokers, 69% intended (without attempt) to quit and 63% attempted (but failed) to quit during the past year. Almost an equal number of students saw antismoking and prosmoking media messages in the last month, and 28% of students were offered free cigarettes by a tobacco company representative. In schools, more than 50% of students were taught about the dangers of cigarette smoking in the last year. Smoking by parents, older brothers, and close friends, watching prosmoking cigarette advertisements, free offer of cigarettes by tobacco company representatives, perception of smoking being not harmful, and continuing smoking which can be easily quit significantly increased the odds of smoking by students. The common use of tobacco in school populations needs to be addressed by, among other tobacco control measures, a strict ban on cigarette selling to minors and intensive regular tobacco control campaigns involving health and religious messages.

  12. Imagine...Opportunities and Resources for Academically Talented Youth, 2001-2002.

    ERIC Educational Resources Information Center

    Hartman, Melissa, Ed.

    2002-01-01

    This collection of 5 issues of Imagine cover the time period from November/December 2001 through May/June 2002. Designed for gifted youth, the issues focus on dramatic arts, physics and astronomy, communications, law and politics, and robotics, and contain the following featured articles: (1) The Story of a Play (Gemma Cooper-Novack); (2)…

  13. [Remarkable restricted tuberculosis epidemics in 2001/2002 in two Bavarian regions].

    PubMed

    Gronauer, W; Pregler, M; Wolf, P

    2004-01-01

    Even if the incidence is further decreasing, tuberculosis must not be underestimated in Germany. In 2001, the public health service revealed four noteworthy molecular-biologically substantiated tuberculosis infection chains in Upper Bavaria and Upper Palatinate. An alcohol-addict frequenting the table reserved for regulars in an inn located in the district of E. was the origin for a small epidemic with seven tuberculosis cases, whereof six were contagious. In the district of D., a manager causes two illnesses at the workplace, and one tuberculosis case as well as two tuberculin conversions after visiting a skiing hut. An external cleaning lady, who had not been examined previously, causes tuberculosis in a three-year old girl in a rehabilitation clinic in the Upper Bavarian district of BT. The cavernous pulmonary tuberculosis, which was not examined for a long period of time in a nursery-school teacher, caused tuberculosis in a three-year-old girl and tuberculin conversion in thirty-four children in the Upper Palatinate region.

  14. Duck Valley Habitat Enhancement and Protection, 2001-2002 Progress Report.

    SciTech Connect

    Allen, Mattie H.; Sellman, Jake

    2003-03-01

    The Duck Valley Indian Reservation's Habitat Enhancement project is an ongoing project designed to enhance and protect critical riparian areas, natural springs, the Owhyee River and its tributaries, and native fish spawning areas on the Reservation. The project commenced in 1997 and addresses the Northwest Power Planning Council's measures 10.8C.2, 10.8C.3, and 10.8C.5 of the 1994 Columbia River Basin Fish and Wildlife Program. The performance period covers dates from April 2001 through August 2002.

  15. Research on Captive Broodstock Programs for Pacific Salmon, 2001-2002 Annual Report.

    SciTech Connect

    Berejikian, Barry; Tezak, E.; Endicott, Rick

    2002-08-01

    The efficacy of captive broodstock programs depends on high in-culture survival and the fitness of cultured salmon after release, either as adults or juveniles. Continuing captive broodstock research designed to improve technology is being conducted to cover all major life history stages of Pacific salmon. The following summarizes some of the work performed and results from the FY 2001 performance period: (1) The incidence of male maturation of age-1 chinook salmon was significantly reduced by reducing growth in the first year of rearing. (2) Experimentally manipulated growth rates of captively-reared coho salmon had significant effects on female maturation rate, egg size, and fecundity, and the effects were stage-specific (i.e., pre-smolt vs. post-smolt). (3) A combination of Renogen and MT239 vaccination of yearling chinook salmon given an acute R. salmoninarum challenge had a significantly longer survival time than the mock-vaccinated group. The survival time was marginally higher than was seen in acutely challenged fish vaccinated with either Renogen or MT239 alone and suggests that a combination vaccine of Renogen and MT239 may be useful as both a prophylactic and therapeutic agent against BKD. (4) Full-sib (inbred) groups of chinook salmon have thus far exhibited lower ocean survival than half-sib and non-related groups. Effects of inbreeding on fluctuating asymmetry did not follow expected patterns. (5) Sockeye salmon were exposed to specific odorants at either the alevin/emergent fry stage or the smolt stage to determine the relative importance of odorant exposure during key developmental periods and the importance of exposure duration. (6) Experimental studies to determine the effects of exercise conditioning on steelhead reproductive behavior and the effects of male body size on chinook salmon fertilization success during natural spawning were completed.

  16. Research on Captive Broodstock Programs for Pacific Salmon, 2001-2002 Annual Report.

    SciTech Connect

    Berejikian, Barry A.; Tezak, E.P.; Endicott, Rick

    2002-08-01

    In the 2000 Federal Columbia River Power System (FCRPS) Biological Opinion, NMFS identified six populations of steelhead and several salmon populations that had dropped to critically low levels and continue to decline. Following thorough risk-benefit analyses, captive propagation programs for some or all of the steelhead (Oncorhynchus mykiss) populations may be required to reduce the risk of extinction, and more programs may be required in the future. Thus, captive propagation programs designed to maintain or rebuild steelhead populations require intensive and rigorous scientific evaluation, much like the other objectives of BPA Project 1993-056-00 currently underway for chinook (O. tshawytscha) and sockeye salmon (O. nerka). Pacific salmon reared to the adult stage in captivity exhibit poor reproductive performance when released to spawn naturally. Poor fin quality and swimming performance, incomplete development of secondary sex characteristics, changes in maturation timing, and other factors may contribute to reduced spawning success. Improving natural reproductive performance is critical for the success of captive broodstock programs in which adult-release is a primary reintroduction strategy for maintaining ESA-listed populations.

  17. Asotin Creek ISCO Water Sample Data Summary: Water Year 2002, Annual Report 2001-2002.

    SciTech Connect

    Peterson, Stacia

    2003-08-01

    The Pomeroy Ranger District operates 3 automated water samplers (ISCOs) in the Asotin Creek drainage in cooperation with the Asotin Model Watershed. The samplers are located on Asotin Creek: Asotin Creek at the mouth, Asotin Creek at Koch site, and South Fork Asotin Creek above the forks. At the end of Water Year (WY) 2001 we decided to sample from Oct. 1 through June 30 of each water year. This decision was based on the difficulty of obtaining good low flow samples, since the shallow depth of water often meant that instrument intakes were on the bed of the river and samples were contaminated with bed sediments. The greatest portion of suspended sediment is transported during the higher flows of fall and especially during the spring snow runoff period, and sampling the shorter season should allow characterization of the sediment load of the river. The ISCO water samplers collected a daily composite sample of 4 samples per day into one bottle at 6-hour intervals until late March when they were reprogrammed to collect 3 samples per day at 8-hour intervals. This was done to reduce battery use since battery failure had become an ongoing problem. The water is picked up on 24-day cycles and brought to the Forest Service Water Lab in Pendleton, OR. The samples are analyzed for total suspended solids (TSS), conductivity, and turbidity. A total dissolved solids value is estimated based on conductivity. The USGS gage, Asotin Creek at the mouth, No.13335050 has been discontinued and there are no discharge records available for this period.

  18. QED's School Market Trends: Teacher Buying Behavior & Attitudes, 2001-2002. Research Report.

    ERIC Educational Resources Information Center

    Quality Education Data, Inc., Denver, CO.

    This study examined teachers' classroom material buying behaviors and trends. Data came from Quality Education Data's National Education Database, which includes U.S. K-12 public, private, and Catholic schools and districts. Researchers surveyed K-8 teachers randomly selected from QED's National Education Database. Results show that teachers spend…

  19. Louisiana School-Based Health Centers Annual Services Report, 2001-2002.

    ERIC Educational Resources Information Center

    Louisiana State Office of Public Health, New Orleans. Dept. of Health and Hospitals.

    Louisiana's initiative to assist local communities in developing and operating school-based health centers (SBHCs), in place since 1991, is a nationally recognized model. Starting with the basic premise that students must be healthy to learn and be educated in order to maintain a healthy lifestyle, this annual report describes the important role…

  20. National Association of Child Advocates 2001/2002 Annual Report from the President.

    ERIC Educational Resources Information Center

    Copeland, Tamara Lucas

    This annual report details the activities of the National Association of Child Advocates (NACA) from June 2001 to June 2002. The report discusses the efforts of NACA to help members protect funding levels for programs supporting children and their families during the nation's economic downturn, including conducting focus groups to test specific…

  1. Charting New Paths: Rural Development in the South. 2001-2002 Annual Report.

    ERIC Educational Resources Information Center

    Southern Rural Development Center, Mississippi State.

    The Southern Rural Development Center (SRDC) seeks to strengthen the capacity of the region's 29 land-grant institutions to address critical, contemporary rural development issues impacting the well-being of people and communities in the rural South. Work force development, education, leadership training, food security, civic engagement, urban…

  2. Still "A Reasonably Equal Share." Update on Educational Equity in Vermont, Year 2001-2002.

    ERIC Educational Resources Information Center

    Jimerson, Lorna

    Vermont's Equal Educational Opportunity Act of 1997, "Act 60," was designed to rectify inequities in the state's funding of public education, as determined by the Vermont Supreme Court. This report examines the degree to which Act 60 has improved conditions over the last 5 years, focusing on the 3 main equity goals of Act 60 and the…

  3. Instructional Technology Assistance Project. Evaluation Report: Year Two, 2001-2002.

    ERIC Educational Resources Information Center

    Porter, Paul

    An evaluation was conducted of the Instructional Technology Assistance Project. Its goals were to promote learning in technologically enhanced classrooms; support adult education (AE) teachers in developing skills and confidence in integrating technology into instruction; and identify exemplary practices in technology enhanced AE. Data sources…

  4. Multicentre surveillance of antimicrobial resistance in enterococci and staphylococci from Colombian hospitals, 2001-2002.

    PubMed

    Arias, C A; Reyes, J; Zúñiga, M; Cortés, L; Cruz, C; Rico, C L; Panesso, D

    2003-01-01

    Invasive isolates of staphylococci and enterococci were collected from 15 tertiary care centres in five Colombian cities from 2001 to 2002. A total of 597 isolates were available for analysis. Identification was confirmed by both automated methods and multiplex PCR assays in a central laboratory. Staphylococcus aureus and coagulase-negative staphylococci (CoNS) corresponded to 49.6% and 29.6% of isolates, respectively, and 20.8% were identified as enterococci. MICs of ampicillin, ciprofloxacin, chloramphenicol, erythromycin, gentamicin, linezolid, oxacillin, rifampicin, teicoplanin, tetracycline, trimethoprim/sulfamethoxazole (SXT) and vancomycin were determined using an agar dilution method as appropriate. Screening for vancomycin-resistant S. aureus was also carried out on brain-heart infusion agar plates supplemented with vancomycin. The presence of mecA and van genes was investigated in methicillin-resistant staphylococci and glycopeptide-resistant enterococci (GRE), respectively. All staphylococci were susceptible to vancomycin, teicoplanin and linezolid. No VISA isolates were found. In S. aureus and CoNS, the lowest rates of resistance were found for SXT (7.4%) and chloramphenicol (10.7%), respectively. Resistance to oxacillin in S. aureus and CoNS was 52% and 73%, respectively. The mecA gene was detected in 97.5% of methicillin-resistant S. aureus isolates. In enterococci, resistance to glycopeptides was 9.7%: vanA (58.3%) and vanB (41.7%) genes were found. Pulsed-field gel electrophoresis indicated that the GRE isolates were closely related. Rates of resistance to ampicillin, ciprofloxacin, chloramphenicol, rifampicin and high levels of gentamicin and streptomycin were 9.7%, 27.4%, 8.9%, 43%, 17% and 28.2%, respectively. All enterococci were susceptible to linezolid.

  5. Second-Tier Database for Ecosystem Focus, 2001-2002 Annual Report.

    SciTech Connect

    Van Holmes, Chris; Muongchanh, Christine; Anderson, James J.

    2002-11-01

    The Second-Tier Database for Ecosystem Focus (Contract 00004124) provides direct and timely public access to Columbia Basin environmental, operational, fishery and riverine data resources for federal, state, public and private entities. The Second-Tier Database known as Data Access in Realtime (DART) integrates public data for effective access, consideration and application. DART also provides analysis tools and performance measures helpful in evaluating the condition of Columbia Basin salmonid stocks.

  6. Hydrologic Resources Management Program and Underground Test Area Project FY 2001-2002 Progress Report

    SciTech Connect

    Rose, T P; Kersting, A B; Harris, L J; Hudson, G B; Smith, D K; Williams, R W; Loewen, D R; Nelson, E J; Allen, P G; Ryerson, F J; Pawloski, G A; Laue, C A; Moran, J E

    2003-08-15

    This report contains highlights of FY 2001 and 2002 technical studies conducted by the Analytical and Nuclear Chemistry Division (ANCD) at Lawrence Livermore National Laboratory (LLNL) in support of the Hydrologic Resources Management Program (HRMP) and the Underground Test Area (UGTA) Project. These programs are administered by the U.S. Department of Energy, National Nuclear Security Administration, Nevada Site Office (NNSA/NSO) through the Defense Programs and Environmental Restoration Divisions, respectively. HRMP-sponsored work emphasizes the Defense Programs goal of responsible management of natural resources at the NTS, while UGTA-funded work focuses on defining the extent of radionuclide contamination in NTS groundwater resulting from underground nuclear testing. The report is organized on a topical basis, and contains eight chapters that reflect the range of technical work performed by LLNL-ANCD in support of HRMP and UGTA. Chapter 1 describes recent hot well sampling efforts at the NTS, and presents the results of chemical and isotopic analyses of groundwater samples from six near-field wells. These include the Cambric (UE-5n), Bilby (U-3cn PS No.2), Bourbon (UE-7nS), Nash (UE-2ce), Tybo/Benham (ER-20-5 No.3), and Almendro (U-19v PS No.1ds) sites. The data generated by the hot well program is vital to the development and validation of contaminant transport models at the NTS. Chapter 2 discusses the results of xenon isotope measurements of groundwater samples from the six near-field wells described in Chapter 1. This work demonstrates that fission xenon is present in the water at levels that are readily measurable and highlights the significant differences in xenon concentrations and isotopic abundances at different sites. These differences provide insight into the early cooling history of nuclear test cavities, and may assist in predicting the distribution of the source term in the near-field environment. Chapter 3 is an investigation of the distribution and abundance of actinides in a nuclear test cavity and chimney. This work demonstrates that early-time processes can widely disperse actinides at low concentrations outside the melt glass, implying that melt glass dissolution may not be the sole mechanism for the release of actinides to groundwater. The study also provides evidence for the isotopic fractionation of plutonium under the extreme conditions accompanying nuclear explosions. In Chapter 4, X-ray absorption spectroscopy measurements were used to determine the redox state of Fe and U in nuclear melt glass samples from the NTS. Both elements were found to occur in mixed valence states (Fe{sup 2+}/Fe{sup 3+} and U{sup 5+}/U{sup 6+}) in all samples. Comparison of the Fe and U redox states with published redox studies of synthetic glasses suggests that plutonium is predominantly in the Pu{sup 4+} oxidation state in the melt glasses. In Chapter 5, alpha autoradiography is used in a NTS field study to investigate the spatial distribution and transport of actinides in soils, and to help identify the size distribution and morphology of the actinide particles. It was found that {alpha}-emitting radionuclides have moved to at least 39 cm depth in the soil profile, far deeper than expected. The methodology that was developed could easily be applied to other field locations where actinides are dispersed in the soil zone. Chapter 6 summarizes the development of a method for measuring environmental levels of {sup 241}Am on the multi-collector inductively coupled plasma mass spectrometer. The method detection limit of 0.017 pCi/L is about two times lower than the best analyses possible by alpha spectrometry. Chapter 7 describes a chlorine-36 study of vertical groundwater transport processes in Frenchman Flat. Mass balance calculations developed from a {sup 36}Cl mixing model at well ER-5-3 No.2 are used to estimate vertical transport fluxes and average vertical flow velocities through the thick volcanic section underlying the basin. The study also documents the variations in {sup 36}Cl/Cl ratios within the three principal hydrostratigraphic units in Frenchman Flat. Chapter 8 discusses an ongoing stable isotope investigation of precipitation and recharge processes in central Nevada. Precipitation, spring water, and shallow infiltration samples have been collected at four locations on a biannual basis since 1999. The results show that winter precipitation accounts for >90% of the recharge at these sites. Lysimeter data suggest that most of the evaporation occurring during recharge is due to water vapor loss through the soil zone during periods of slow infiltration. In addition to the topical investigations described above, LLNL-ANCD contributed to several other major collaborative technical products during FY 2001 and 2002.

  7. Student Financial Aid Handbook, 2001-2002. Volume 1: Student Eligibility.

    ERIC Educational Resources Information Center

    Department of Education, Washington, DC. Student Financial Assistance.

    This volume discusses the eligibility requirements for student and parent borrowers from federal financial aid programs. It reviews the factors an aid administrator must consider when reviewing a student's application for a loan and outlines the administrator's responsibilities in checking to make sure that recipients qualify for their aid awards.…

  8. Student Financial Aid Handbook, 2001-2002. Volume 2: Institutional Eligibility and Participation.

    ERIC Educational Resources Information Center

    Department of Education, Washington, DC. Student Financial Assistance.

    The purpose of this publication is to describe how a school becomes eligible to participate in the Student Financial Assistance (SFA) programs and to explain the administrative and fiscal requirements of SFA program participation. In addition, this publication discusses other issues relevant to the general administration of the SFA programs. Major…

  9. VizieR Online Data Catalog: Las Campanas Infrared Survey (Chen+, 2001-2002)

    NASA Astrophysics Data System (ADS)

    Chen, H.-W.; McCarthy, P. J.; Marzke, R. O.; Wilson, J.; Carlberg, R. G.; Firth, A. E.; Persson, S. E.; Sabbey, C. N.; Lewis, J. R.; McMahon, R. G.; Lahav, O.; Ellis, R. S.; Martini, P.; Abraham, R. G.; Oemler, A.; Murphy, D. C.; Somerville, R. S.; Beckett, M. G.; Mackay, C. D.

    2002-06-01

    The Las Campanas Infrared Survey, based on broadband optical and near-infrared photometry, is designed to robustly identify a statistically significant and representative sample of evolved galaxies at redshifts z>1. We have completed an H-band imaging survey over 1.1{deg}2 of sky in six separate fields. The average 5{sigma} detection limit in a 4" diameter aperture is H~20.8. Here we describe the design of the survey, the observation strategies, data-reduction techniques, and object identification procedures. We present sample near-infrared and optical photometric catalogs for objects identified in two survey fields. The optical images of the Hubble Deep Field-South region obtained from the literature reach 5{sigma} detection thresholds in a 4" diameter aperture of U~24.6, B~26.1, V~25.6, R~25.1, and I~24.2mag. The optical images of the Chandra Deep Field-South region obtained from our own observations reach 5 {sigma} detection thresholds in a 4" diameter aperture of V~26.8, R~26.2, I~25.3, and z'~23.7mag. We perform object detection in all bandpasses and identify>~54000 galaxies over 1408 arcmin2 of sky in the two fields. Of these galaxies, ~14000 are detected in the H band and ~2000 have the colors of evolved galaxies, I-H >~3, at z>~1. (3 data files).

  10. Walla Walla River Basin Fish Habitat Enhancement Project, 2001-2002 Annual Report.

    SciTech Connect

    Volkman, Jed; Sexton, Amy D.

    2003-04-01

    In 2001, the Confederated Tribes of the Umatilla Indian Reservation (CTUIR) Fisheries Habitat Program implemented stream habitat restoration and protection efforts in the Walla Walla River Basin with funding from Bonneville Power Administration (BPA). The objective of these efforts is to protect and restore habitat critical to the recovery of weak or reintroduced populations of salmonid fish. The CTUIR has currently enrolled six properties into this program: two on Couse Creek, two adjacent properties on Blue Creek, one on Patit Creek, and one property on the mainstem Walla Walla River. Since 1997, approximately 7 miles of critical salmonid habitat has been secured for restoration and protection under this project. Major accomplishments to date include the following: Secured approximately $250,000 in cost share; Secured 7 easements; Planted 30,000+ native plants; Installed 50,000+ cuttings; and Seeded 18 acres to native grass. Pre and post-project monitoring efforts were included for all projects, incorporating methodologies from CTUIR's Draft Monitoring Plan. Basin-wide monitoring also included the deployment of 6 thermographs to collect summer stream temperatures.

  11. [Government funding for health and the reliability of national databases in Brazil, 2001-2002].

    PubMed

    Lima, Claudia Risso de Araujo; Carvalho, Marilia Sá; Schramm, Joyce Mendes de Andrade

    2006-09-01

    Created in 1999, the Information System on Government Health Budgets (SIOPS) provides information on health revenues and expenditures at the three government levels: Municipal, State, and Federal. The lack of other databases with nationwide coverage and detailed information on municipal expenditures makes SIOPS the main source of data for such studies or estimates. The current study aims to compare the revenues declared in SIOPS by the municipalities and the National Health Fund records in order to assess the reliability of the two databases and identify which variables are most discordant. It also compares the data on Municipal expenditures with those from National Treasury records. The Intra-Class Correlation Coefficient (CCIC) was used for this analysis, complemented by a scatterplot of the mean values for the two databases and their differences. The 2002 data showed better quality. The recognition that SIOPS provides reliable data should stimulate new studies including financial aspects in the analysis of population health.

  12. Underrecognition of leptospirosis during a dengue fever outbreak in Hawaii, 2001-2002.

    PubMed

    Ellis, Tania; Imrie, Allison; Katz, Alan R; Effler, Paul V

    2008-08-01

    During the 10-year period from 1997 through 2006, the reported mean annual incidence rate of leptospirosis in the state of Hawaii was 3.3/100,000 with a range of 22-60 infections reported each year. Because the clinical presentation is highly variable, however, leptospirosis illness is challenging to recognize and may be underdiagnosed. To assess whether the incidence may be substantially higher than reported figures indicate, we retrospectively studied the prevalence of anti-Leptospira IgM antibodies among specimens obtained over a 12-month period (May 2001 to April 2002) from patients presenting with febrile illness during a dengue fever outbreak in Hawaii. Of 1206 patients testing negative or indeterminate for dengue, 54 (4.5%; 95% confidence interval: 3.3%-5.7%) were positive for anti-Leptospira IgM antibodies using a commercially available dipstick enzyme-linked immunosorbent assay (ELISA). The most common clinical symptoms reported by laboratory-positive leptospirosis patients were fever (92%), headache (88%), and myalgia (83%). Three clinical symptoms were significantly less common among persons laboratory positive for leptospirosis when compared with the 122 patients who had been diagnosed with dengue fever during the outbreak: rash (p < 0.0001), chills (p = 0.05), and petechiae (p = 0.0005). Laboratory-positive leptospirosis infections were identified in persons exposed on each of the 5 most populous islands and illness onsets spanned a 10-month period, reflecting an endemic pattern of disease. If added to the figures obtained via routine passive surveillance, the number of leptospirosis infections identified through this study would more than double the annual incidence rate for Hawaii during 2001. These findings indicate that many leptospiral infections in Hawaii go undiagnosed. Physicians should maintain a high index of suspicion for leptospirosis when assessing patients presenting with acute febrile illness among residents and visitors to Hawaii.

  13. The Class of 2002 Four-Year Longitudinal Report and 2001-2002 Event Dropout Rates.

    ERIC Educational Resources Information Center

    Waddington, Susan

    This study examined the progress toward school completion of students who entered ninth grade in fall 1998 and were scheduled to graduate on time in spring 2002 after 4 years of high school, offering outcomes for the class as a whole and for specific groups of students categorized by gender, native language, race/ethnicity, and immigrant status.…

  14. Student Financial Aid Handbook, 2001-2002. Application and Verification Guide.

    ERIC Educational Resources Information Center

    Department of Education, Washington, DC. Student Financial Assistance.

    This publication is intended for financial aid administrators and counselors who are helping students in the initial phases of the student aid process as they file the Free Application for Federal Student Aid (FAFSA), verify the information they submit, and make corrections and changes to FAFSA information. The material in this guide was part of…

  15. Wisconsin Technical College System Board 2001-2002 Graduate Follow-Up Report.

    ERIC Educational Resources Information Center

    Wisconsin Technical Coll. System Board, Madison.

    The Wisconsin Technical College System (WTCS) conducts an annual Graduate Follow-Up Survey to gather data regarding the activities and perceptions of students approximately 6 months after their graduation from the colleges. The primary objectives of the survey are to identify the current activities of program graduates, to determine the extent to…

  16. McKenzie River Watershed Coordination, Annual Report 2001-2002.

    SciTech Connect

    Thrailkil, Jim

    2003-11-01

    BPA funding, in conjunction with contributions from numerous partners organizations and grant funds supports the McKenzie Watershed Council's (MWC) efforts to coordinate restoration and monitoring programs of federal, state, local government, and residents within the watershed. Primary goals of the MWC are to improve resource stewardship and conserve fish, wildlife, and water quality resources. Underpinning the goals is the MWC's baseline program centered on relationship building and information sharing. Objectives for FY02 included: (1) Continue to coordinate McKenzie Watershed activities among diverse groups to restore fish and wildlife habitat in the watershed, with a focus on the middle to lower McKenzie, including private lands and the McKenzie-Willamette confluence area; (2) Influence behavior of watershed residents to benefit watershed function though an outreach and education program, utilizing (BPA funded) Assessment and Conservation Strategy information to provide a context for prioritized action; (3) Continue to maintain and sustain a highly functional watershed council; (4) Maintain and improve water quality concerns through the continuation of Council-sponsored monitoring and evaluation programs; and (5) Continue to secure other funding for watershed restoration and protection projects and Council operations.

  17. 2001-2002 Annual Report to the Ministry of Advanced Education

    ERIC Educational Resources Information Center

    British Columbia Council on Admissions and Transfer, 2002

    2002-01-01

    The mandate of the British Columbia Council on Admissions and Transfer is to support and facilitate effective articulation, transfer, and admission arrangements for students wishing to move between the province's colleges, institutes, university colleges and universities. Its key role is to encourage the collaborative leadership that is required…

  18. 78 FR 64984 - Distribution of the 2000, 2001, 2002 and 2003 Cable Royalty Funds

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-30

    ... International, The Potter's House of Dallas, Inc. d/b/a T.D. Jakes Ministries, and Zola Levitt Ministries... analyses offered by the parties. I. Background Beginning June 3, 2013, the Judges considered testimony of... Syndications, Inc., Marty Stouffer Productions, Ltd., Martha Stewart Living Omnimedia, Reel Funds International...

  19. Student Financial Aid Handbook, 2001-2002. Volume 4: Campus-Based Common Provisions.

    ERIC Educational Resources Information Center

    Department of Education, Washington, DC. Student Financial Assistance.

    The Federal Perkins Loan, Federal Supplemental Educational Opportunity Grant (FSEOG), and Federal Work-Study (FWS) programs are called "campus-based" programs because each school is responsible for administering them on its own campus. A school applies for and receives funds direct from the U.S. Department of Education, and the school's…

  20. A Profile of the Student Support Services Program, 1998-1999 through 2001-2002

    ERIC Educational Resources Information Center

    Zhang, Yu; Chan, Tsze; Hale, Margaret; Kirshstein, Rita

    2005-01-01

    This report is the third in a series of reports that present a national profile of the Student Support Services (SSS) Program. It presents grantee data from 2000-01 and 2001-02 for the first time and includes data from earlier years for comparison purposes. The following are appended: (1) Response Rates and Data Issues; (2) Risk Factors of 1995-96…

  1. Book Review: Distant wanderers / Copernicus Books/Springer , 2001/2002

    NASA Astrophysics Data System (ADS)

    Bhatt, H. C.

    2002-06-01

    Are we alone in the Universe? The Earth, teeming with life, as we know it, is only one amongst the nine planets (wanderers) that wander around the Sun in more or less circular orbits. Do distant stars also have planets circling them? Are some of them similar to Earth and support life? These questions have long occupied the human mind. However, until the closing years of the twentieth century, the idea that there are stars, other than the Sun, that have planets orbiting them, remained a subject of speculation and controversy because the astronomical observing techniques used for the detection of planetary companions of stars did not have the necessary precision. During the past several years, advances in technology and dedicated efforts of planet-hunting astronomers have made it possible to detect Jupiter-like or more massive planets around nearby stars. So far about 70 such extra-solar planets have been discovered indicating that our solar system is not unique and distant wanderers are not uncommon. Distant Wanderers narrates the story of the search for extra-solar planets, even as the search is becoming more vigorous with newer instruments pushing the limits of sensitivity that has often resulted in the detection of planetary systems with totally unexpected characteristics. The book is primarily aimed at non specialists, but practicing scientists, including astronomers, will find the narrative very interesting and sometimes offering a perspective that is unfamiliar to professionals. The book begins with an introduction to some basic astronomical facts about the Universe, evolution of stars, supernovae and formation of pulsars. The first extra-solar planets were discovered in 1992 around a radio pulsar (PSR 1257+12) by measuring the oscillatory perturbations in the pulse arrival times from the pulsar caused by the presence of orbiting earth-sized planets as their gravity forces the pulsar also to move in orbit around the system barycenter. Such planetary systems are, however, very rare and only one other planet around a pulsar has so far been found. The first extra-solar planet around a sun-like star was discovered in 1995 by M. Mayor and D. Queloz circling the star 51 Pegasi by the method of Doppler spectroscopy. Since then about 70 extra-solar planets have been discovered. Most of these have been detected by Doppler spectroscopy, but now newer methods like occultation and gravitational lensing have also begun to reveal extra-solar planets and candidate extra-solar planets. Distant Wanderers gives a brief description of current theories of planet formation in dusty disks around stars as they form by gravitational collapse of rotating interstellar clouds. Various techniques used by astronomers for the detection of extra-solar planets are discussed. Important astrophysical concepts relevant to planet formation and their detection are also explained. The reader is taken to observatories on mountain tops, laboratories where instruments are built and conferences where astronomers announce their discoveries, debate the results and discuss future strategies for the search for distant wanderers. The extra-solar planets discovered so far, around sun-like stars, are similar in mass to Jupiter or more massive. Their orbits show a great variety. Some are in very close orbits (orbital periods of a few days) about the parent star, and are therefore very hot (hot Jupiters), while others are in wider orbits and cold. Some have nearly circular orbits, while many of them have highly eccentric orbits. There are extra-solar planets with masses as large as about 10 times the mass of Jupiter, close to being brown dwarfs. The existence of such planetary systems was never predicted by the standard theories of planet and star formation. As the hunt for extra-solar planets continues with more sophisticated instruments using innovative ideas, astronomers can be sure to be rewarded with more surprises. In Distant Wanderers, these discoveries and technological developments, currently taking place and being planned for the future, in the search for extra-solar planets, are narrated by the author, Bruce Dorminey, in simple language and lucid style. There are a few technical errors in the book. For example, on page 4, the angular momentum , which must always be conserved, is said to be created. In the discussion of the proper motion (which is measured on the plane of the sky) of Barnard's star, on page 111, it is incorrect to say that the star is moving toward the Sun. The book is, otherwise, well written and succeeds in communicating the excitement of the hunt for the distant wanderers.

  2. The Perfect Tens: The Top Twenty Books Reviewed in "Voice of Youth Advocates" 2001-2002.

    ERIC Educational Resources Information Center

    Voice of Youth Advocates, 2003

    2003-01-01

    Explains the review procedures and rating system for teen books in "Voice of Youth Advocates" and provides annotated bibliographies for the twenty best books in 2001-2202, including fiction, nonfiction, and science fiction and fantasy. (LRW)

  3. Natural Production Monitoring and Evaluation; Idaho Department of Fish and Game, 2001-2002 Annual Report.

    SciTech Connect

    Kiefer, Russell B.; Bunn, Paul; Johnson, June

    2002-06-01

    This report covers the following 3 chapters: Part 1--Improve wild steelhead trout smolt-to-adult survival rate information by PIT tagging additional wild steelhead trout juveniles. Part 2--Estimating the stock-recruitment relationship for Snake River spring/summer chinook salmon and forecasting wild/natural smolt production. Part 3--Monitoring age composition of wild adult spring and summer chinook salmon returning to the Snake River basin.

  4. (En)Gendering Responsibility: A Critical News Analysis of Argentina's Education Reform, 2001-2002

    ERIC Educational Resources Information Center

    Robert, Sarah A.

    2012-01-01

    Education reform continues around the globe, though questioned and critiqued in relation to goals of democratizing educational decision-making. Newspapers are one site of contestation and negotiation where struggles over global reform discourses are contextualized in "obvious" and "natural" local language. In this article, I…

  5. Host-feeding patterns of suspected West Nile virus mosquito vectors in Delaware, 2001-2002.

    PubMed

    Gingrich, Jack B; Williams, Gregory M

    2005-06-01

    Paucity of data on host-feeding patterns and behavior of 43 mosquito species that are reported as suspected West Nile virus (WN) vectors has limited full evaluation of their vectorial capacity. Recent studies addressing this issue need additional confirmation and should also be expanded to include collections of species or subpopulations attracted to humans. We used 4 types of collection methods to collect mosquitoes, including omnidirectional Fay-Prince traps, Centers for Disease Control-type light traps, gravid traps, and human-landing collections. Mosquitoes were collected during 2 full WN transmission seasons in 2001 and 2002, at 9 different sites across Delaware. We collected from various habitats, including salt marshes, brackish water areas, woodlands, a tire dump, a racetrack, and a mushroom farm. Blood-meal analyses were performed on parous mosquitoes by using a sandwich-type enzyme-linked immunosorbent assay. We tested primarily for 5 common host species, including rabbits, dogs, deer, horses, and chickens. We obtained substantial host-feeding data from 8 mosquito species. The most mammalophilic species were Anopheles quadrimaculatus, Coquillettidia perturbans, and Aedes albopictus, whereas the most ornithophilic species was Culex pipiens. Aedes albopictus was the most anthropophilic species, whereas Ae. vexans and Cq. perturbans exhibited relatively low attraction to humans. Culex salinarius was the species with the most diverse host-feeding activity. Based on feeding behavior, Cx. pipiens and Cx. salinarius appear to be the most likely bridge vectors. Other species may have opportunities to be bridge vectors under special circumstances, as discussed in the paper.

  6. Alternative Schools Accountability Model: 2001-2002 Indicator Selection and Reporting Guide.

    ERIC Educational Resources Information Center

    California State Dept. of Education, Sacramento.

    California has developed an alternative accountability system for schools with fewer than 100 students, alternative schools of various kinds, community day schools, and other schools under the jurisdiction of a county board of education or a county superintendent of schools. This document is a guide to assist local administrators in completing the…

  7. SURVEILLANCE FOR DRINKING WATER-ASSOCIATED OUTBREAKS-UNITED STATES, 2001-2002

    EPA Science Inventory

    Problem/Condition: Since 1971, CDC, the U.S. Environmental Protection
    Agency (EPA), and the Council of State and Territorial Epidemiologists CSTE) have maintained a collaborative surveillance system for collecting and periodically reporting data related to occurrences and cau...

  8. Fairmont State College GEAR UP Project: Year 3 Baseline Survey (2001-2002).

    ERIC Educational Resources Information Center

    Cowley, Kimberly S.; Finch, Nicole; Blake, Jennifer

    In 1999, Fairmont State College (FSC) received a U.S. Department of Education grant to implement Project GEAR UP (Gaining Early Awareness and Readiness for Undergraduate Programs) in nine primarily-rural counties of West Virginia. GEAR UP encourages disadvantaged youth to have high expectations, stay in school, and take academically rigorous…

  9. Imagine...Opportunities and Resources for Academically Talented Youth, 2001-2002.

    ERIC Educational Resources Information Center

    Hartman, Melissa, Ed.

    2002-01-01

    This collection of 5 issues of Imagine cover the time period from November/December 2001 through May/June 2002. Designed for gifted youth, the issues focus on dramatic arts, physics and astronomy, communications, law and politics, and robotics, and contain the following featured articles: (1) The Story of a Play (Gemma Cooper-Novack); (2)…

  10. QED's School Market Trends: Internet Usage in Teaching, 2001-2002. QED Research Report.

    ERIC Educational Resources Information Center

    Quality Education Data, Inc., Denver, CO.

    This report presents results of a survey of curriculum subject (language arts, math, science, and/or social studies) teachers of grades 1-12 on Internet usage. The sample was public schools in Quality Education Data's National Education Database. A total of 350 surveys were completed in March through May 2001. Findings are reported in the…

  11. High Resolution Doppler Imager FY 2001,2002,2003 Operations and Algorithm Maintenance

    NASA Technical Reports Server (NTRS)

    Skinner, Wilbert

    2004-01-01

    During the performance period of this grant HRDI (High Resolution Doppler Imager) operations remained nominal. The instrument has suffered no loss of scientific capability and operates whenever sufficient power is available. Generally, there are approximately 5-7 days per month when the power level is too low to permit observations. The daily latitude coverage for HRDI measurements in the mesosphere, lower thermosphere (MLT) region are shown.It shows that during the time of this grant, HRDI operations collected data at a rate comparable to that achieved during the UARS (Upper Atmosphere Research Satellite) prime mission (1991 -1995). Data collection emphasized MLT wind to support the validation efforts of the TIDI instrument on TIMED, therefore fulfilling one of the primary objectives of this phase of the UARS mission. Skinner et al., (2003) present a summary of the instrument performance during this period.

  12. Literacy Teaching and Learning: An International Journal of Early Reading and Writing, 2001-2002.

    ERIC Educational Resources Information Center

    Literacy Teaching and Learning: An International Journal of Early Reading and Writing, 2002

    2002-01-01

    This scholarly journal, an official publication of the Reading Recovery Council of North America, was established to provide an interdisciplinary forum on issues related to the acquisition of language, literacy development, and instructional theory and practice. Articles in Volume 6, Number 1 are: "Documenting and Developing Literacy in Deaf…

  13. Alternative Schools Accountability Model: 2001-2002 Indicator Selection and Reporting Guide.

    ERIC Educational Resources Information Center

    California State Dept. of Education, Sacramento.

    California has developed an alternative accountability system for schools with fewer than 100 students, alternative schools of various kinds, community day schools, and other schools under the jurisdiction of a county board of education or a county superintendent of schools. This document is a guide to assist local administrators in completing the…

  14. Description of Seismicity at Volcan de Colima, MEXICO, in the Period 2001-2002

    NASA Astrophysics Data System (ADS)

    Reyes-Davila, G. A.; Nunez-Cornu, F. J.; Ramirez-Vazquez, C. A.; Suarez-Plascencia, C.

    2002-12-01

    After the february 2001 explosive activity at Volcan de Colima, Mexico, the seismic activity decreased to its lowest level since november 1997 when the actual period of activity started. However, a few months later several researchers reported important morphologic changes inside of the crater formed by the explosive activity, which did not have related seismic activity. During the rainy season it was not possible to follow the development of the changes inside the crater and no significative seismicity was detected. Starting october 2001, a seismic swarm started to develop consisting mainly by high frecuency, very low amplitude seismic events usually detected by the closest seismic station to the summit, at about 1 km. By the end of the month the seismicity almost disappeared, but then it was possible to view again the volcano and for the first time it was possible to observe a huge spine extrusion. From november and until february 2002 it was possible to visually follow, by flying in helicopter, the process. Asismically, new lava was extruded until it filled the crater and a new lava dome was emplaced on the volcano. On february 5, 2002 the new material started to flow down the slopes of the volcano forming lava fronts mainly toward the southwest sector. Apparently the lava extrusion rate was almost constant. Beginning april, short periods of tremor started to appear sporadically and later it begun increasing continuosly in duration, amplitude and spectral content to levels not previously seen at Volcan de Colima. Such situation prompted a preventive evacuation of the people living close to the volcano and at greater risk. However, ending may, 2002 the seismic activity suddenly decreased in a stepwise way and later slowly decreased until a new minimum was reached by the end of june. However, starting july, seismicity started to increased again until a stable level was reached and continues until now. During the whole process, low level, small explosive type events have been detected.A detailed discussion is presented in that presentation.

  15. Lake Roosevelt Rainbow Trout Habitat/Passage Improvement Project, Annual Report 2001-2002.

    SciTech Connect

    Sears, Sheryl

    2003-01-01

    The construction of Chief Joseph and Grand Coulee Dams completely and irrevocably blocked anadromous fish migrations to the Upper Columbia River. Historically this area hosted vast numbers of salmon returning to their natal waters to reproduce and die. For the native peoples of the region, salmon and steelhead were a principle food source, providing physical nourishment and spiritual sustenance, and contributing to the religious practices and the cultural basis of tribal communities. The decaying remains of spawned-out salmon carcasses contributed untold amounts of nutrients into the aquatic, aerial, and terrestrial ecosystems of tributary habitats in the upper basin. Near the present site of Kettle Falls, Washington, the second largest Indian fishery in the state existed for thousands of years. Returning salmon were caught in nets and baskets or speared on their migration to the headwater of the Columbia River in British Columbia. Catch estimates at Kettle Falls range from 600,000 in 1940 to two (2) million around the turn of the century (UCUT, Report No.2). The loss of anadromous fish limited the opportunities for fisheries management and enhancement exclusively to those actions addressed to resident fish. The Lake Roosevelt Rainbow Trout Habitat/Passage Improvement Project is a mitigation project intended to enhance resident fish populations and to partially mitigate for anadromous fish losses caused by hydropower system impacts. This substitution of resident fish for anadromous fish losses is considered in-place and out-of-kind mitigation. Upstream migration and passage barriers limit the amount of spawning and rearing habitat that might otherwise be utilized by rainbow trout. The results of even limited stream surveys and habitat inventories indicated that a potential for increased natural production exists. However, the lack of any comprehensive enhancement measures prompted the Upper Columbia United Tribes Fisheries Center (UCUT), Colville Confederated Tribes (CCT), Spokane Tribe of Indians (STI) and Washington Department of Fish and Wildlife (WDFW) to develop and propose a comprehensive fishery management plan for Lake Roosevelt. The Rainbow Trout Habitat/Passage Improvement Project (LRHIP) was designed with goals directed towards increasing natural production while maintaining genetic integrity among current tributary stocks. The initial phase of the Lake Roosevelt Habitat Improvement Project (Phase I, baseline data collection: 1990-91) was focused on the assessment of limiting factors, including the quality and quantity of available spawning gravel, identification of passage barriers, and assessment of other constraints. After the initial assessment of stream parameters, five streams meeting specific criteria were selected for habitat/passage improvement projects (Phase II, implementation -1992-1995). Four of these projects were on the Colville Indian Reservation South Nanamkin, North Nanamkin, Louie and Iron Creeks and one Blue Creek was on the Spokane Indian Reservation. At the completion of project habitat improvements, the final phase (Phase III, monitoring-1996-2000) began. This phase assessed the changes and determined the success achieved through the improvements. Data analysis showed that passage improvements are successful for increasing habitat availability and use. The results of in-stream habitat improvements were inconclusive. Project streams, to the last monitoring date, have shown increases in fish density following implementation of the improvements. In 2000 Bridge Creek, on the Colville Reservation was selected for the next phase of improvements. Data collection, including baseline stream survey and population data collection, was carried out during 2001 in preparation for the design and implementation of stream habitat/passage improvements. Agencies cooperating on the project include the Colville Confederated Tribes (CCT), Natural Resource Conservation Service (NRCS, Ferry County District), Ferry County Conservation District, and Ferry County. The Bonneville Power Administration (BPA) provided project funding support and program integration assistance. A stock of redband rainbow trout, were discovered in 2001 in an isolated section of Bridge Creek above a set of waterfalls. DNA microsatellite analysis was conducted at the University of Idaho and indicated that very little if any hybridization. The targeted species in the genetic analysis was red band/rainbow trout (Oncorhynchus mykiss spp.). The sub-contract is with Madison Powell and Joyce Faler at the Center for Salmonid and Freshwater Species at Risk at the University of Idaho/HFCES. DNA analysis used mitochondrial and nuclear RFLP markers along with two microsatellite loci. Sample populations were screened for detectable levels of introgressive hybridization arising from possible admixtures of hatchery rainbow trout with native red band trout.

  16. A miniaturised laser ablation/ionisation analyser for investigation of elemental/isotopic composition with the sub-ppm detection sensitivity

    NASA Astrophysics Data System (ADS)

    Tulej, M.; Riedo, A.; Meyer, S.; Iakovleva, M.; Neuland, M.; Wurz, P.

    2012-04-01

    analysis of solid materials on the planetary surfaces (Rohner et al., 2003). Initial laboratory tests that were conducted with an IR laser radiation for the ablation, atomisation and ionisation of the material, indicated a high performance of the instrument in terms of sensitivity, dynamic range and mass resolution (Tulej et al., 2011). After some technical improvements and implementation of a computer-controlled performance optimiser we have achieved further improvements of both, the instrumental sensitivity down to sub-ppm level and reproducibility of the measurements. We will demonstrate the potential of the mass analyser to perform the quantitative elemental analysis of solids with a spatial (vertical, lateral) resolution commensurate with typical grain sizes, and its capabilities for investigation of isotopic patterns with accuracy and precision comparable to that of large analytical laboratory instruments, e.g., TIMS, SIMS, LA-ICP-MS. The results can be of considerable interest for in situ dating or investigation of other fine isotopic fractionation effects including studies of bio-markers.

  17. Detection of ultraviolet radiation using tissue equivalent radiochromic gel materials

    NASA Astrophysics Data System (ADS)

    Bero, M. A.; Abukassem, I.

    2009-05-01

    Ferrous Xylenol-orange Gelatin gel (FXG) is known to be sensitive to ionising radiation such as γ and X-rays. The effect of ionising radiation is to produce an increase in the absorption over a wide region of the visible spectrum, which is proportional to the absorbed dose. This study demonstrates that FXG gel is sensitive to ultraviolet radiation and therefore it could functions as UV detector. Short exposure to UV radiation produces linear increase in absorption measured at 550nm, however high doses of UV cause the ion indicator colour to fad away in a manner proportional to the incident UV energy. Light absorbance increase at the rate of 1.1% per minute of irradiation was monitored. The exposure level at which the detector has linear response is comparable to the natural summer UV radiation. Evaluating the UV ability to pass through tissue equivalent gel materials shows that most of the UV gets absorbed in the first 5mm of the gel materials, which demonstrate the damaging effects of this radiation type on human skin and eyes. It was concluded that FXG gel dosimeter has the potential to offer a simple, passive ultraviolet radiation detector with sensitivity suitable to measure and visualises the natural sunlight UV exposure directly by watching the materials colour changes.

  18. The features of radiation dose variations onboard ISS and Mir space station: comparative study.

    PubMed

    Tverskaya, L V; Panasyuk, M I; Reizman, S Ya; Sosnovets, E N; Teltsov, M V; Tsetlin, V V

    2004-01-01

    The dynamics of the ISS-measured radiation dose variations since August 2000 is studied. Use is made of the data obtained with the R-16 instrument, which consists of two ionization chambers behind different shielding thicknesses. The doses recorded during solar energetic particle (SEP) events are compared with the data obtained also by R-16 on Mir space station. The SEP events in the solar maximum of the current cycle make a much smaller contribution to the radiation dose compared with the October 1989 event recorded on Mir space station. In the latter event, the proton intensity was peaking during a strong magnetic storm. The storm-time effect of solar proton geomagnetic cutoff decreases on dose variations is estimated. The dose variations on Mir space stations due to formation of a new radiation belt of high-energy protons and electrons during a sudden commencement of March 24, 1991 storm are also studied. It was for the first time throughout the ISS and Mir dose measurement period that the counting rates recorded by both R-16 channels on ISS in 2001-2002 were nearly the same during some time intervals. This effect may arise from the decreases of relativistic electron fluxes in the outer radiation belt. c2004 COSPAR. Published by Elsevier Ltd. All rights reserved.

  19. Some characteristics and effects of natural radiation.

    PubMed

    Mc Laughlin, J P

    2015-11-01

    Since life first appeared on the Earth, it has, in all its subsequent evolved forms including human, been exposed to natural radiation in the environment both from terrestrial and extra-terrestrial sources. Being an environmental mutagen, ionising natural radiation may have played a role of some significance in the evolution of early life forms on Earth. It has been estimated by United Nations Scientific Committee on the Effects of Atomic Radiation that at the present time, exposure to natural radiation globally results in an annual average individual effective dose of about 2.4 mSv. This represents about 80 % of the total dose from all sources. The three most important components of natural radiation exposure are cosmic radiation, terrestrial radioactivity and indoor radon. Each of these components exhibits both geographical and temporal variabilities with indoor radon exposure being the most variable and also the largest contributor to dose for most people. In this account, an overview is given of the characteristics of the main components of the natural radiation environment and some of their effects on humans. In the case of cosmic radiation, these range from radiation doses to aircrew and astronauts to the controversial topic of its possible effect on climate change. In the case of terrestrial natural radiation, accounts are given of a number of human exposure scenarios. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  20. Application of atmospheric pressure chemical ionisation mass spectrometry in the analysis of barbiturates by high-speed analytical countercurrent chromatography.

    PubMed

    Jones, Jonathan J; Kidwell, Huw; Games, David E

    2003-01-01

    Four barbiturates (barbital, allobarbital, phenobarbital and butalbital) were analysed using high-speed analytical countercurrent chromatography (HSACCC) and high-performance liquid chromatography (HPLC) interfaced with mass spectrometry, using negative mode atmospheric pressure chemical ionisation (APCI). The polar biphasic solvent system of butyronitrile/acetonitrile/water (1:1:1) was used, in the upper-stationary, lower-mobile mode of operation, at a flow rate of 1 mL/min and a rotational speed of 1200 rpm, equating to an applied "g"-field of 177 g. The fractional stationary phase retention (S(F)) was 0.58. Representative mass spectral data are presented from the HPLC and the HSACCC analyses. Structural information was obtained using source-induced fragmentation at increased source block voltages. The effect of increasing g-field on chromatographic resolution is illustrated using the binary base system of butyronitrile/water (1:1), under electrospray ionisation. Copyright 2003 John Wiley & Sons, Ltd.

  1. Fast nucleotide identification through fingerprinting using gold nanoparticle-based surface-assisted laser desorption/ionisation.

    PubMed

    Larguinho, Miguel; Capelo, José L; Baptista, Pedro V

    2013-02-15

    We report a method centred on gold nanoparticle-based surface-assisted laser desorption/ionisation for analysis of deoxynucleotides and alkylated nucleobases. Gold nanoparticles allow for enhanced analysis capability by eliminating undesired signature peaks; thus more elegant mass spectra can be attained that allow identification by nucleotide mass fingerprint. The resulting fingerprinting patterns on the spectra are compared and associated with the presence of different nucleotides in the sample. This method can be easily extended to modified nucleotides implicated in genome lesions due to exposure to environment chemicals, such as DNA adducts (e.g. guanine adducts). The use of gold nanoparticles for surface-assisted laser desorption/ionisation can be an useful tool to resolve common issues of background noise when analysing nucleic acids samples.

  2. Potential errors in relative dose measurements in kilovoltage photon beams due to polarity effects in plane-parallel ionisation chambers.

    PubMed

    Dowdell, S; Tyler, M; McNamara, J; Sloan, K; Ceylan, A; Rinks, A

    2016-11-15

    Plane-parallel ionisation chambers are regularly used to conduct relative dosimetry measurements for therapeutic kilovoltage beams during commissioning and routine quality assurance. This paper presents the first quantification of the polarity effect in kilovoltage photon beams for two types of commercially available plane-parallel ionisation chambers used for such measurements. Measurements were performed at various depths along the central axis in a solid water phantom and for different field sizes at 2 cm depth to determine the polarity effect for PTW Advanced Markus and Roos ionisation chambers (PTW-Freiburg, Germany). Data was acquired for kilovoltage beams between 100 kVp (half-value layer (HVL)  =  2.88 mm Al) and 250 kVp (HVL  =  2.12 mm Cu) and field sizes of 3-15 cm diameter for 30 cm focus-source distance (FSD) and 4  ×  4 cm(2)-20  ×  20 cm(2) for 50 cm FSD. Substantial polarity effects, up to 9.6%, were observed for the Advanced Markus chamber compared to a maximum 0.5% for the Roos chamber. The magnitude of the polarity effect was observed to increase with field size and beam energy but was consistent with depth. The polarity effect is directly influenced by chamber design, with potentially large polarity effects for some plane-parallel ionisation chambers. Depending on the specific chamber used, polarity corrections may be required for output factor measurements of kilovoltage photon beams. Failure to account for polarity effects could lead to an incorrect dose being delivered to the patient.

  3. Potential errors in relative dose measurements in kilovoltage photon beams due to polarity effects in plane-parallel ionisation chambers

    NASA Astrophysics Data System (ADS)

    Dowdell, S.; Tyler, M.; McNamara, J.; Sloan, K.; Ceylan, A.; Rinks, A.

    2016-12-01

    Plane-parallel ionisation chambers are regularly used to conduct relative dosimetry measurements for therapeutic kilovoltage beams during commissioning and routine quality assurance. This paper presents the first quantification of the polarity effect in kilovoltage photon beams for two types of commercially available plane-parallel ionisation chambers used for such measurements. Measurements were performed at various depths along the central axis in a solid water phantom and for different field sizes at 2 cm depth to determine the polarity effect for PTW Advanced Markus and Roos ionisation chambers (PTW-Freiburg, Germany). Data was acquired for kilovoltage beams between 100 kVp (half-value layer (HVL)  =  2.88 mm Al) and 250 kVp (HVL  =  2.12 mm Cu) and field sizes of 3-15 cm diameter for 30 cm focus-source distance (FSD) and 4  ×  4 cm2-20  ×  20 cm2 for 50 cm FSD. Substantial polarity effects, up to 9.6%, were observed for the Advanced Markus chamber compared to a maximum 0.5% for the Roos chamber. The magnitude of the polarity effect was observed to increase with field size and beam energy but was consistent with depth. The polarity effect is directly influenced by chamber design, with potentially large polarity effects for some plane-parallel ionisation chambers. Depending on the specific chamber used, polarity corrections may be required for output factor measurements of kilovoltage photon beams. Failure to account for polarity effects could lead to an incorrect dose being delivered to the patient.

  4. An evaluation of radiation damage to solid state components flown in low earth orbit satellites.

    PubMed

    Shin, Myung-Won; Kim, Myung-Hyun

    2004-01-01

    The effects of total ionising radiation dose upon commercial off-the-shelf semiconductors fitted to satellites operating in low Earth orbit (LEO) conditions was evaluated. The evaluation was performed for the Korea Institute of Technology SATellite-1, (KITSAT-1) which was equipped with commercial solid state components. Two approximate calculation models for space radiation shielding were developed. Verification was performed by comparing the results with detailed three-dimensional calculations using the Monte-Carlo method and measured data from KITSAT-1. It was confirmed that the developed approximate models were reliable for satellite shielding calculations. It was also found that commercial semiconductor devices, which were not radiation hardened, could be damaged within their lifetime due to the total ionising dose they are subject to in the LEO environment. To conclude, an intensive shielding analysis should be considered when commercial devices are used.

  5. A multiple methods approach: radiation associated cataracts and occupational radiation safety practices in interventionalists in South Africa.

    PubMed

    Rose, A; Rae, W I D; Chikobvu, P; Marais, W

    2017-06-26

    Ionising radiation is a modality used in diagnostic and therapeutic medicine. The technology has improved and resulted in lower dose exposure but there has been an escalation in the quantity of procedures, their duration and complexity. These factors have meant increased occupational radiation exposure for interventionalists. Ionising radiation exposure can have detrimental health effects and includes radiation skin burns, various carcinomas, genetic and chromosomal aberrations and cataractogenesis of the lenses of the eye. The lenses of the eye are of the most radiosensitive organs and the risk of cataracts is high despite low radiation dose exposures. The use of personal protective equipment (PPE) is a method that can be used to mitigate the risk for developing lens opacifications. The consistent and effective utilisation of PPE is marred by availability, proper fit and ease of use when performing procedures. Radiation safety training is imperative to enforce a culture of radiation safety among interventionalists. The aim of this study was to quantify and describe cataracts among South African interventionalists and to understand their radiation safety practices. For this purpose, a cross sectional study was designed using multiple methods. A survey was conducted to determine the demographics and the risk factors of doctors exposed to radiation to doctors not exposed. The radiation workload and radiation safety practices of interventionalists were explored. Both groups had slit lamp examinations. The data were analysed analytically and a regression model developed looking at the outcomes and the risk factors. Qualitative in-depth interviews and group interviews were conducted to explore the perceptions of interventionalists regarding radiation safety. Deductive and inductive thematic analysis was done. Interdisciplinary research is challenging but offers tremendous opportunity for exploring and tackling complex issues related to securing a safe radiation work

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

    NASA Astrophysics Data System (ADS)

    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. Investigation of the ionisation density dependence of the glow curve characteristics of LIF:MG,TI (TLD-100)

    PubMed Central

    Horowitz, Y. S.; Horowitz, A.; Oster, L.; Marino, S.; Datz, H.; Margaliot, M.

    2008-01-01

    The dependence of the shape of the glow curve of LiF:Mg,Ti (TLD-100) on ionisation density was investigated using irradiation with 90Sr/90Y beta rays, 60 and 250 kVp X rays, various heavy-charged particles and 0.2 and 14 MeV neutrons. Special attention is focused on the properties of high-temperature thermoluminescence; specifically, the behaviour of the high-temperature ratio (HTR) of Peaks 7 and 8 as a function of batch and annealing protocol. The correlation of Peaks 7 and 8 with average linear-energy-transfer (LET) is also investigated. The HTR of Peak 7 is found to be independent of LET for values of LET approximately >30 keV µm−1. The behaviour of the HTR of Peak 8 with LET is observed to be erratic, which suggests that applications using the HTR should separate the contributions of Peaks 7 and 8 using computerised glow curve deconvolution. The behaviour of the HTR following neutron irradiation is complex and not fully understood. The shape of composite Peak 5 is observed to be broader following high ionisation alpha particle irradiation, suggesting that the combined use of the HTR and the shape of Peak 5 could lead to improved ionisation density discrimination for particles of high LET. PMID:18667402

  8. Spectrometre de masse a ionisation Penning selective: Elimination des corrections necessaires a la determination du rapport isotopique de l'hydrogene

    NASA Astrophysics Data System (ADS)

    Letarte, Sylvain

    Dans le but d'ameliorer la precision avec laquelle le rapport isotopique de l'hydrogene peut etre determine, un spectrometre de masse a ionisation Penning a ete construit pour provoquer l'ionisation selective de l'hydrogene moleculaire et de l'hydrure de deuterium a partir d'un melange gazeux. L'utilisation d'atomes dans des etats d'excitation metastable s'est averee une solution adequate pour reponde a cette attente. L'emploi de l'helium, a l'interieur d'une source d'atomes metastables construit specifiquement pour ce travail, ne permet pas d'obtenir un spectre de masse compose uniquement des deux molecules d'interet. L'ionisation de ces dernieres provient de deux processus distincts, soient l'ionisation Penning et l'ionisation par bombardement electronique. Contrairement a l'helium, il a ete demontre que le neon metastable est un candidat ideal pour produire l'ionisation selective de type Penning. Le nombre d'ions produits est directement proportionnel au courant de la decharge electrique et de la pression d'operation de la source d'atomes metastables. Ces resultats demontrent le potentiel d'un tel spectrometre de masse pour ameliorer la precision a laquelle le rapport isotopique peut etre determine comparativement aux autres techniques existantes.

  9. Radiation dose-reduction strategies in thoracic CT.

    PubMed

    Moser, J B; Sheard, S L; Edyvean, S; Vlahos, I

    2017-05-01

    Modern computed tomography (CT) machines have the capability to perform thoracic CT for a range of clinical indications at increasingly low radiation doses. This article reviews several factors, both technical and patient-related, that can affect radiation dose and discusses current dose-reduction methods relevant to thoracic imaging through a review of current techniques in CT acquisition and image reconstruction. The fine balance between low radiation dose and high image quality is considered throughout, with an emphasis on obtaining diagnostic quality imaging at the lowest achievable radiation dose. The risks of excessive radiation dose reduction are also considered. Inappropriately low dose may result in suboptimal or non-diagnostic imaging that may reduce diagnostic confidence, impair diagnosis, or result in repeat examinations incurring incremental ionising radiation exposure. Copyright © 2016 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

  10. 100 years of Cosmic Rays - from the ionisation of air to beyond the LHC

    NASA Astrophysics Data System (ADS)

    Watson, Alan

    2012-03-01

    The study of cosmic rays has impacted on many disciplines, including astrophysics, particle physics, carbon dating and radio astronomy: it has thus had scientific and societal impact. They were discovered in 1912 as a result of the efforts by some of the most distinguished scientists of that era, puzzled by their inability to explain the discharge of ionisation chambers. I will describe some of the early work that led, inter alia, to the discovery of the positron, the muon and the first strange particles and thus to the birth of particle physics. In 1938 it was found that showers of particles that arrive at the earth simultaneously are produced by primary cosmic rays of ˜10^15 eV, about 10^5 times more energetic than any particles that had been contemplated before. I will discuss how study of these showers has led to the discovery of cosmic rays of energies as great as 3 x 10^20 eV, challenging our understanding of where and how they are created. Data from the Pierre Auger Observatory, the largest cosmic-ray detector ever built, is now being used for astrophysical studies and to give glimpses of some hadronic physics at centre-of-mass energies more than 4 times greater than are accessible at the LHC.

  11. Variability in the H +3 emission of Saturn: Consequences for ionisation rates and temperature

    NASA Astrophysics Data System (ADS)

    Melin, Henrik; Miller, Steve; Stallard, Tom; Trafton, L. M.; Geballe, T. R.

    2007-01-01

    We present an analysis of observations of the auroral/polar regions of Saturn, carried out in 1999, 2004 and 2005, making use of the facility spectrometer, CGS4, on the United Kingdom Infrared Telescope (UKIRT), Mauna Kea, Hawaii. We obtain temperatures of 380(±70) K in 1999 and 420(±70) K in 2004. (The 2005 data has insufficient spectral resolution for a temperature determination to be made.) Our most probable interpretation is that the temperature of Saturn's auroral/polar H +3 layer should be taken as 400(±50) K. This is lower than the value obtained by Miller et al. [Miller, S., and 10 colleagues, 2000. Philos. Trans. R. Soc. 358, 2485-2502], which is shown to be in error. Our analysis reveals clearly that the line emission due to H +3 varies considerably, showing nearly an order of magnitude increase when one compares the data obtained in 1999 with those of 2004. Our conclusion is that this variability is (mainly) due to the changing H +3 column density. By analogy with modelling results obtained for Jupiter, we estimate that the particle (keV electron) precipitation experienced by Saturn must be ˜20 times greater in 2004 than in 1999, to produce this additional ionisation. The H +3 emission increases, but this is insufficient to offset most of the heating due to the extra particle precipitation, indicating that this ion does not act as a "thermostat" on Saturn, in the same way that it does on Jupiter.

  12. Resolving Ionisation and Metallicity on Parsec Scales Across Primordial Analogues with HST-WFC3

    NASA Astrophysics Data System (ADS)

    James, B. L.; Auger, M.; Calzetti, D.; Kewley, L.; Aloisi, A.; Pettini, M.; Trussler, J.

    2016-06-01

    Nearby Blue Compact Dwarf (BCD) galaxies are excellent laboratories for conducting detailed spatially resolved spectroscopic analyses of star-formation (SF), feedback, and chemical evolution in relatively pristine, low-metallicity environments analogous to those thought to exist in the early Universe. In this talk I will show a new, extensive dataset of narrow-band HST-WFC3 imaging where I essentially use HST as a high-spatial-resolution IFU to map six major emission lines in unprecedented detail, including HeII emission from WR stars. In this pioneering study, I spatially resolve diagnostic line ratios on sub-pc scales in two BCDs and deduce which ionisation mechanisms (e.g. shocks and/or photoionisation) are at work and assess their role in shaping the global galaxy properties. Moreover, I will present the first 'metallicity image' of a star-forming galaxy, revealing inhomogeneities on scales as small as <50~pc. This work not only demonstrates the benefits of high-resolution spatially-resolved observations in assessing the effects of feedback mechanisms and accurate chemical abundances, but also the limitations of emission line diagnostic tools which can break down on scales smaller than a H II region. Both aspects are especially relevant as we enter the era of extremely large telescopes, when observing structure on ˜~10~pc scales will no longer be limited to the local universe.

  13. Free energy for blue copper protein unfolding determined by electrospray ionisation mass spectrometry.

    PubMed

    Cunsolo, V; Foti, S; La Rosa, C; Saletti, R; Canters, G W; Verbeet, M P

    2001-01-01

    An electrospray ionisation (ESI) mass spectrometric method for the determination of the free energy (DeltaG) of unfolding of proteins is described. The method was tested using three blue copper proteins: wild type azurin, Cys-3Ala/Cys-26Ala (C3A/C26A) azurin mutant and wild-type amicyanin. The time course of the denaturation process of the proteins dissolved in methanol/water (50:50, v/v, pH 3.5) was followed by recording ESI mass spectra at time intervals. The spectra showed two series of peaks, corresponding to the native holo-protein and the unfolded apo-protein. From the intensity ratio of these two series of peaks at increasing time and at equilibrium, the free energy for the unfolding process for the three proteins could be determined. To evaluate the reliability of the thermodynamic data obtained by the ESI mass spectrometric approach, the denaturation process was followed by UV-VIS spectroscopy. The two sets of data obtained by these independent methods were in good agreement indicating that the ESI-MS approach can be used to obtain reliable quantitative information about the protein unfolding process. In principle, this approach can be applied to other proteins and requires very low amounts of sample, due to the intrinsic sensitivity of mass spectrometry. This may prove particularly useful when the amount of sample available prevents the use of current methods.

  14. Assessment of risk to wildlife from ionising radiation: can initial screening tiers be used with a high level of confidence?

    PubMed

    Beresford, N A; Hosseini, A; Brown, J E; Cailes, C; Beaugelin-Seiller, K; Barnett, C L; Copplestone, D

    2010-06-01

    A number of models are being used to assess the potential environmental impact of releases of radioactivity. These often use a tiered assessment structure whose first tier is designed to be highly conservative and simple to use. An aim of using this initial tier is to identify sites of negligible concern and to remove them from further consideration with a high degree of confidence. In this paper we compare the screening assessment outputs of three freely available models. The outputs of these models varied considerably in terms of estimated risk quotient (RQ) and the radionuclide-organism combinations identified as being the most limiting. A number of factors are identified as contributing to this variability: values of transfer parameters (concentration ratios and K(d)) used; organisms considered; different input options and how these are utilised in the assessment; assumptions as regards secular equilibrium; geometries and exposure scenarios. This large variation in RQ values between models means that the level of confidence required by users is not achieved. We recommend that the factors contributing to the variation in screening assessments be subjected to further investigation so that they can be more fully understood and assessors (and those reviewing assessment outputs) can better justify and evaluate the results obtained.

  15. Overview of ICRP Committee 1: radiation effects.

    PubMed

    Morgan, W F

    2016-06-01

    This paper does not necessarily reflect the views of the International Commission on Radiological Protection. The author passed away on 13 November 2015.Committee 1 of the International Commission on Radiological Protection (ICRP) addresses issues pertinent to tissue reactions, risks of cancer and heritable diseases, radiation dose responses, effects of dose rate, and radiation quality. In addition, it reviews data on the effects of radiation on the embryo/fetus, genetic factors in radiation response, and uncertainties in providing judgements on radiation-induced health effects. Committee 1 advises the Main Commission on the biological basis of radiation-induced health effects, and how epidemiological, experimental, and theoretical data can be combined to make quantitative judgements on health risks to humans. The emphasis is on low radiation doses, in the form of detriment-adjusted nominal risk coefficients, where there are considerable uncertainties in terms of the biology and the epidemiology. Furthermore, Committee 1 reviews data from radiation epidemiology studies and publications on the molecular and cellular effects of ionising radiation relevant to updating the basis of the 2007 Recommendations published in ICRP Publication 103 This paper will provide an overview of the activities of Committee 1, the updated work of the Task Groups and Working Parties, and the future activities being pursued.

  16. Chemical analyses of micrometre-sized solids by a miniature laser ablation/ionisation mass spectrometer (LMS)

    NASA Astrophysics Data System (ADS)

    Tulej, Marek; Wiesendanger, Reto; Neuland, Maike; Meyer, Stefan; Wurz, Peter; Neubeck, Anna; Ivarsson, Magnus; Riedo, Valentine; Moreno-Garcia, Pavel; Riedo, Andreas; Knopp, Gregor

    2017-04-01

    Investigation of elemental and isotope compositions of planetary solids with high spatial resolution are of considerable interest to current space research. Planetary materials are typically highly heterogenous and such studies can deliver detailed chemical information of individual sample components with the sizes down to a few micrometres. The results of such investigations can yield mineralogical surface context including mineralogy of individual grains or the elemental composition of of other objects embedded in the sample surface such as micro-sized fossils. The identification of bio-relevant material can follow by the detection of bio-relevant elements and their isotope fractionation effects [1, 2]. For chemical analysis of heterogenous solid surfaces we have combined a miniature laser ablation mass spectrometer (LMS) (mass resolution (m/Dm) 400-600; dynamic range 105-108) with in situ microscope-camera system (spatial resolution ˜2um, depth 10 um). The microscope helps to find the micrometre-sized solids across the surface sample for the direct mass spectrometric analysis by the LMS instrument. The LMS instrument combines an fs-laser ion source and a miniature reflectron-type time-of-flight mass spectrometer. The mass spectrometric analysis of the selected on the sample surface objects followed after ablation, atomisation and ionisation of the sample by a focussed laser radiation (775 nm, 180 fs, 1 kHz; the spot size of ˜20 um) [4, 5, 6]. Mass spectra of almost all elements (isotopes) present in the investigated location are measured instantaneously. A number of heterogenous rock samples containing micrometre-sized fossils and mineralogical grains were investigated with high selectivity and sensitivity. Chemical analyses of filamentous structures observed in carbonate veins (in harzburgite) and amygdales in pillow basalt lava can be well characterised chemically yielding elemental and isotope composition of these objects [7, 8]. The investigation can be

  17. Multi-directional radiation detector using photographic film

    NASA Astrophysics Data System (ADS)

    Junet, L. K.; Majid, Z. A. Abdul; Sapuan, A. H.; Sayed, I. S.; Pauzi, N. F.

    2014-11-01

    Ionising radiation has always been part of our surrounding and people are continuously exposed to it. Ionising radiation is harmful to human health, thus it is vital to monitor the radiation. To monitor radiation, there are three main points that should be observed cautiously, which are energy, quantity, and direction of the radiation sources. A three dimensional (3D) dosimeter is an example of a radiation detector that provide these three main points. This dosimeter is able to record the radiation dose distribution in 3D. Applying the concept of dose detection distribution, study has been done to design a multi-directional radiation detector of different filter thicknesses. This is obtained by designing a cylinder shaped aluminum filter with several layers of different thickness. Black and white photographic material is used as a radiation-sensitive material and a PVC material has been used as the enclosure. The device is then exposed to a radiation source with different exposure factors. For exposure factor 70 kVp, 16 mAs; the results have shown that optical density (OD) value at 135° is 1.86 higher compared with an OD value at 315° which is 0.71 as the 135° area received more radiation compare to 315° region. Furthermore, with an evidence of different angle of film give different value of OD shows that this device has a multidirectional ability. Materials used to develop this device are widely available in the market, thus reducing the cost of development and making it suitable for commercialisation.

  18. Ionised concentrations in calcium and magnesium buffers: Standards and precise measurement are mandatory.

    PubMed

    McGuigan, John A S; Kay, James W; Elder, Hugh Y

    2016-09-01

    In Ca(2+) and Mg(2+) buffer solutions the ionised concentrations ([X(2+)]) are either calculated or measured. Calculated values vary by up to a factor of seven due to the following four problems: 1) There is no agreement amongst the tabulated constants in the literature. These constants have usually to be corrected for ionic strength and temperature. 2) The ionic strength correction entails the calculation of the single ion activity coefficient, which involves non-thermodynamic assumptions; the data for temperature correction is not always available. 3) Measured pH is in terms of activity i.e. pHa. pHa measurements are complicated by the change in the liquid junction potentials at the reference electrode making an accurate conversion from H(+) activity to H(+) concentration uncertain. 4) Ligands such as EGTA bind water and are not 100% pure. Ligand purity has to be measured, even when the [X(2+)] are calculated. The calculated [X(2+)] in buffers are so inconsistent that calculation is not an option. Until standards are available, the [X(2+)] in the buffers must be measured. The Ligand Optimisation Method is an accurate and independently verified method of doing this (McGuigan & Stumpff, Anal. Biochem. 436, 29, 2013). Lack of standards means it is not possible to compare the published [Ca(2+)] in the nmolar range, and the apparent constant (K(/)) values for Ca(2+) and Mg(2+) binding to intracellular ligands amongst different laboratories. Standardisation of Ca(2+)/Mg(2+) buffers is now essential. The parameters to achieve this are proposed. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Accurate simulation of ionisation chamber response with the Monte Carlo code PENELOPE

    NASA Astrophysics Data System (ADS)

    Sempau, Josep; Andreo, Pedro

    2011-08-01

    Ionisation chambers (IC) are routinely used in hospitals for the dosimetry of the photon and electron beams used for radiotherapy treatments. The determination of absorbed dose to water from the absorbed dose to the air filling the cavity requires the introduction of stopping power ratios and perturbation factors, which account for the disturbance caused by the presence of the chamber. Although this may seem a problem readily amenable to Monte Carlo simulation, the fact is that the accurate determination of IC response has been, for various decades, one of the most important challenges of the simulation of electromagnetic showers. The main difficulty stems from the use of condensed history techniques for electron and positron transport. This approach, which involves grouping a large number of interactions into a single artificial event, is known to produce the so-called interface effects when particles travel across surfaces separating different media. These effects can be sizeable when the electron step length is not negligible compared to the size of the region being crossed, as it is the case with the cavity of an IC. The artefact, which becomes apparent when the chamber response shows a marked dependence on the adopted step size, can be palliated with the use of sophisticated electron transport algorithms. These topics are discussed in the context of the transport model implemented in the PENELOPE code. The degree of violation of the Fano theorem for a simple, planar geometry, is used as a measure of the stability of the algorithm with respect to variations of the electron step length, thus assessing the "quality" of its condensed history scheme. It is shown that, with a suitable choice of transport parameters, PENELOPE simulates IC response with an accuracy of the order of 0.1%.

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

    NASA Astrophysics Data System (ADS)

    Gaensler, B. M.; Madsen, G. J.; Chatterjee, S.; Mao, S. A.

    2008-11-01

    We present a new joint analysis of pulsar dispersion measures and diffuse Hα 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 1830-250+120 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 typical electron density 0.34 +/- 0.06 cm-3 with a volume filling factor 0.04 +/- 0.01. As one moves off the plane, the filling factor increases to a maximum of ~30% at a height of ~1-1.5 kpc, before then declining to accommodate the increasing presence of hot, coronal gas. Since models for the WIM with a ~1 kpc scale-height have been widely used to estimate distances to radio pulsars, our revised parameters suggest that the distances to many high-latitude pulsars have been substantially underestimated.

  1. Screening for medium chain acyl-CoA dehydrogenase deficiency using electrospray ionisation tandem mass spectrometry

    PubMed Central

    Clayton, P.; Doig, M.; Ghafari, S.; Meaney, C.; Taylor, C.; Leonard, J.; Morris, M.; Johnson, A.

    1998-01-01

    OBJECTIVE—To establish criteria for the diagnosis of medium chain acyl-CoA dehydrogenase (MCAD) deficiency in the UK population using a method in which carnitine species eluted from blood spots are butylated and analysed by electrospray ionisation tandem mass spectrometry (ESI-MS/MS).
DESIGN—Four groups were studied: (1) 35 children, aged 4 days to 16.2 years, with proven MCAD deficiency (mostly homozygous for the A985G mutation, none receiving carnitine supplements); (2) 2168control children; (3) 482 neonates; and (4) 15 MCAD heterozygotes.
RESULTS—All patients with MCAD deficiency had an octanoylcarnitine concentration ([C8-Cn]) > 0.38 µM and no accumulation of carnitine species > C10 or < C6. Among the patients with MCAD deficiency, the [C8-Cn] was significantly lower in children > 10 weeks old and in children with carnitine depletion (free carnitine < 20 µM). Neonatal blood spots from patients with MCAD deficiency had a [C8-Cn] > 1.5 µM, whereas in heterozygotes and other normal neonates the [C8-Cn] was < 1.0 µM. In contrast, the blood spot [C8-Cn] in eight of 27 patients with MCAD deficiency > 10 weeks old fell within the same range as five of 15 MCAD heterozygotes (0.38-1.0 µM). However, the free carnitine concentrations were reduced (< 20 µM) in the patients with MCAD deficiency but normal in the heterozygotes.
CONCLUSIONS—Criteria for the diagnosis of MCAD deficiency using ESI-MS/MS must take account of age and carnitine depletion. If screening is undertaken at 7-10 days, the number of false positive and negative results should be negligible. Because there have been no instances of death or neurological damage following diagnosis of MCAD deficiency in our patient group, a strong case can be made for neonatal screening for MCAD deficiency in the UK.

 PMID:9797589

  2. Contribution to the Interpretation of Emission-line spectra in Ionised Nebulae

    NASA Astrophysics Data System (ADS)

    Rola, C. S.

    1995-05-01

    The study of ionised nebulae from their emission-line intensities is the aim of this work. It concerns two complementary aspects. Firstly, we have studied the influence of the emission-line detection and measurement procedures in the values of the measured intensities. Secondly, we have developed diagnostic methods for the determination of the nature and physical properties of emission-line objects, using a minimum number of line intensities. Detailed simulations of the emission-line detection and intensity measurement procedures allowed us to estimate the errors committed in the intensity measurement of lines with low signal-to-noise ratio. Obtained results permitted us to show the existence of a bias in the measured intensities distribution and to determine a model for it. Furthermore, we determined analytically the probability distribution function of a intensity lines ratio. In this context, we have studied the effect of uncertainties in the intensity measures, and of temperature fluctuations in the determination of the C/O abundance ratio in planetary nebulae. With the purpose of determining the characteristics and the nature of emission-line objects having only a few line intensities available, we calculated the upper limits for photoionisation by OB stars in diagnostic diagrams. For this we build an extensive grid of photoionisation models covering a wide range of physical conditions in H II regions. The results obtained were used in the determination of the nature of the "Canada-France Redshift Survey" emission-line field galaxies, showing the importance of this type of diagnostic in deep redshift surveys.

  3. Identification of differentially expressed proteins of gamma-ray irradiated rat intestinal epithelial IEC-6 cells by two-dimensional gel electrophoresis and matrix-assisted laser desorption/ionisation-time of flight mass spectrometry.

    PubMed

    Bo, Zhang; Yongping, Su; Fengchao, Wang; Guoping, Ai; Yongjiang, Wei

    2005-02-01

    To identify proteins involved in the processes of cellular and molecular response to radiation damage repair in intestinal epithelial IEC-6 cells, we comparatively analyzed the proteome of irradiated IEC-6 cells with that of normal cells. A series of methods were used, including two-dimensional gel electrophoresis (Z-DE), PDQuest software analysis of 2-DE gels, peptide mass fingerprinting based on matrix-assisted laser desorption/ionisation-time of flight-mass spectrometry (MALDI-TOF-MS), and Swiss-Prot database searching, to separate and identify differentially expressed proteins. Western blotting and reverse transcriptase polymerase chain reaction (RT-PCR) were used to validate the differentially expressed proteins. Image analysis revealed that averages of 608 +/- 39 and 595 +/- 31 protein spots were detected in normal and irradiated IEC-6 cells, respectively. Sixteen differential protein spots were isolated from gels, and measured with MALDI-TOF-MS. A total of 14 spots yielded good spectra, and 11 spots matched with known proteins after database searching. These proteins were mainly involved in anti-oxidation, metabolism, and protein post-translational processes. Western blotting confirmed that stress-70 protein was down-regulated by gamma-irradiation. Up-regulation of ERP29 was confirmed by RT-PCR, indicating that it is involved in ionizing radiation. The clues provided by the comparative proteome strategy utilized here will shed light on molecular mechanisms of radiation damage repair in intestinal epithelial cells.

  4. Radiation safety: what can happen in an accident.

    PubMed

    Scully, C; de Almeida, O P

    1992-04-11

    Radiation hazards in dental practice have long been recognized, and the dangers from ionising radiation during dental radiography are discussed elsewhere. Continuing legislation will undoubtedly help reduce the risk of over-exposure and accidents. Nevertheless, it is of some concern that radiation safety is still ignored by some: for example, one recent survey in the UK showed that not all radiography sets conformed to modern safety standards. However, the profession also has reason to be concerned about more public radiation hazards that may affect them, and their families and others, and may, without denying the importance of dental radiation protection, have far greater effects on health. Well-known examples of domestic radon exposure occurred in the UK, particularly in the Lake District and the South West, and the nuclear reactor accidents--notably at Chernobyl in 1986.

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

    PubMed

    Kowatari, Munehiko; Tanimura, Yoshihiko; Tsutsumi, Masahiro

    2014-12-01

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

  6. The inverse-square gamma-irradiation anomaly of the Nuclear Enterprises 2575 large-volume ionisation chamber.

    PubMed

    Bielajew, Alex F; Tessier, Frédéric; El Gamal, Islam

    2015-12-01

    The Nuclear Enterprises (Model 2575) 600 cc ionisation chamber is examined to discover the cause of its anomalous behaviour in inverse-square stability measurements. Measurements and Monte Carlo calculations are employed to isolate the cause of the discrepancy. It is found that most of the effect is due to the long photon attenuation pathlengths in the long side wall of the instrument. A phenomenological procedure, based on measurements, is proposed to correct for the anomaly. The procedure results in inverse-square stability to within 0.5 % over a range of 1-7 m.

  7. Interpretation of ionospheric F-region structures in the vicinity of ionisation troughs observed by satellite radio tomography

    NASA Astrophysics Data System (ADS)

    Aladjev, G. A.; Evstafiev, O. V.; Mingalev, V. S.; Mingaleva, G. I.; Tereshchenko, E. D.; Khudukon, B. Z.

    2001-01-01

    Tomographic images of the spatial distribution of electron density in the ionospheric F-region are presented from the Russian-American Tomography Experiment (RATE) in November 1993 as well as from campaigns carried out in northern Scandinavia in November 1995 and in Russia in April 1990. The reconstructions selected display the ionisation troughs above the tomographic chains of receivers during geomagnetically quiet and disturbed periods. Two mathematical models of the high-latitude ionosphere developed in the Polar Geophysical Institute have been applied for interpretation of the observed tomographic images.

  8. Capillary electrophoresis with electrospray ionisation-mass spectrometry for the characterisation of degradation products in aged papers.

    PubMed

    Dupont, Anne-Laurence; Seemann, Agathe; Lavédrine, Bertrand

    2012-01-30

    A methodology for capillary electrophoresis/electrospray ionisation mass spectrometry (CE/ESI-MS) was developed for the simultaneous analysis of degradation products from paper among two families of compounds: low molar mass aliphatic organic acids, and aromatic (phenolic and furanic) compounds. The work comprises the optimisation of the CE separation and the ESI-MS parameters for improved sensitivity with model compounds using two successive designs of experiments. The method was applied to the analysis of lignocellulosic paper at different stages of accelerated hygrothermal ageing. The compounds of interest were identified. Most of them could be quantified and several additional analytes were separated.

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

    PubMed

    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. Development of a rest gas ionisation profile monitor for the CERN Proton Synchrotron based on a Timepix3 pixel detector

    NASA Astrophysics Data System (ADS)

    Levasseur, S.; Dehning, B.; Gibson, S.; Sandberg, H.; Sapinski, M.; Sato, K.; Schneider, G.; Storey, J.

    2017-02-01

    A fast non-destructive transverse profile monitor, named PS Beam Gas Ionization monitor (PS- BGI), is under development at CERN for the Proton Synchrotron (PS). This monitor infers the beam profile from the transverse distribution of electrons created by the ionisation of rest gas molecules by the high energy beam particles. The distribution is measured by accelerating the electrons onto an imaging detector based on Timepix3 (TPX3). This detector consists of hybrid pixel detector assemblies mounted on a ceramic carrier board and flexible printed circuit cables which have been developed specifically for operation in an ultra high vacuum environment.

  11. The solar ionisation rate deduced from Ulysses measurements and its implications to interplanetary Lyman alpha-intensity

    NASA Technical Reports Server (NTRS)

    Summanen, T.; Kyroelae, E.

    1995-01-01

    We have developed a computer code which can be used to study 3-dimensional and time-dependent effects of the solar cycle on the interplanetary (IP) hydrogen distribution. The code is based on the inverted Monte Carlo simulation. In this work we have modelled the temporal behaviour of the solar ionisation rate. We have assumed that during the most of the time of the solar cycle there is an anisotopic latitudinal structure but right at the solar maximum the anisotropy disappears. The effects of this behaviour will be discussed both in regard to the IP hydrogen distribution and IP Lyman a a-intensity.

  12. Evaluation of a pulse-discharge helium ionisation detector for the determination of neon concentrations by gas chromatography.

    PubMed

    Lasa, J; Mochalski, P; Pusz, J

    2004-05-07

    A pulse-discharge helium ionisation detector, PDHID (Valco, PD-D2-I) with sample introduced to the discharge zone is shown to be applicable for reliable determinations of neon by gas chromatography. The detection level of 80 pg was obtained, but the dependence between detector response and neon mass was non-linear. However, for the discharge gas doped with 33 ppm of neon, a linear response to the neon mass up to 10(-5) g and the detection level of 0.5 ng were obtained. The method can be used for measuring neon concentrations in groundwater systems for hydrogeological purposes.

  13. Radiation burden from secondary doses to patients undergoing radiation therapy with photons and light ions and radiation doses from imaging modalities.

    PubMed

    Gudowska, I; Ardenfors, O; Toma-Dasu, I; Dasu, A

    2014-10-01

    Ionising radiation is increasingly used for the treatment of cancer, being the source of a considerable fraction of the medical irradiation to patients. With the increasing success rate of cancer treatments and longer life expectancy of the treated patients, the issue of secondary cancer incidence is of growing concern, especially for paediatric patients who may live long after the treatment and be more susceptible to carcinogenesis. Also, additional imaging procedures like computed tomography, kilovoltage and megavoltage imaging and positron emission tomography, alone or in conjunction with radiation therapy, may add to the radiation burden associated with the risk of occurrence of secondary cancers. This work has been based on literature studies and is focussed on the assessment of secondary doses to healthy tissues that are delivered by the use of modern radiation therapy and diagnostic imaging modalities in the clinical environment.

  14. Radiation effects: Modulating factors and risk assessment -- an overview.

    PubMed

    Wakeford, R

    2012-01-01

    Following low dose or low dose-rate exposures to ionising radiation, the principal resulting radiation-related risk is cancer. Site-specific cancer risk models have been developed that describe how the radiation-induced risk of a particular cancer type varies with the relevant tissue-specific absorbed dose of radiation. The degree of risk will also be determined by the radiation quality and the dose-rate, factors that will vary between types of radiation and cancer. Risk models also include a number of intrinsic factors that modify the radiation-related excess risk - sex, age at exposure, time since exposure, and attained age - although not all these factors enter into each site-specific model. Of some importance is how the radiation-related excess risk is transferred between populations when background incidence rates differ. For most cancer types, expert groups consider that the radiation-related excess risk in a population depends, to some extent, upon the background incidence rate, and therefore that radiation interacts with at least some of the major risk factors that determine the background risk for a person. For example, the radiation-induced risk of lung cancer depends on the degree of individual exposure to tobacco smoke, but the implicit assumption of the currently accepted risk transfer models is that interactions are a general feature of radiation-related cancer risk.

  15. Enabling Radiative Transfer on AMR grids in CRASH

    NASA Astrophysics Data System (ADS)

    Hariharan, N.; Graziani, L.; Ciardi, B.; Miniati, F.; Bungartz, H.-J.

    2017-01-01

    We introduce CRASH-AMR, a new version of the cosmological Radiative Transfer (RT) code CRASH, enabled to use refined grids. This new feature allows us to attain higher resolution in our RT simulations and thus to describe more accurately ionisation and temperature patterns in high density regions. We have tested CRASH-AMR by simulating the evolution of an ionised region produced by a single source embedded in gas at constant density, as well as by a more realistic configuration of multiple sources in an inhomogeneous density field. While we find an excellent agreement with the previous version of CRASH when the AMR feature is disabled, showing that no numerical artifact has been introduced in CRASH-AMR, when additional refinement levels are used the code can simulate more accurately the physics of ionised gas in high density regions. This result has been attained at no computational loss, as RT simulations on AMR grids with maximum resolution equivalent to that of a uniform cartesian grid can be run with a gain of up to 60% in computational time.

  16. New laboratory atomic data for neutral, singly and doubly ionised iron group elements for astrophysics applications

    NASA Astrophysics Data System (ADS)

    Pickering, Juliet C.; Nave, Gillian; Liggins, Florence; Clear, Christian; Ruffoni, Matthew; Sansonetti, Craig

    2015-08-01

    We present new laboratory spectroscopic measurements to produce atomic data for astrophysically important species: neutral, singly and doubly ionised iron group elements.We use high resolution Fourier Transform Spectrometry (FTS) (resolving power up to 2x106 at 200nm) to measure atomic spectra, giving accurate line wavelengths (to a few parts in 108), atomic energy levels, hyperfine structure splitting and log gfs (accurate to a few %) (Ruffoni et al this meeting). These data are vital for astrophysical spectral analyses for: line identification, spectrum synthesis, elemental abundance determinations [eg 1], and disentangling of blends etc. It is not possible to theoretically calculate these atomic data to the accuracy needed for modern astrophysics applications.At Imperial College we have a unique visible-VUV FT spectrometer with short wavelength cut-off of 135nm. We supplement FTS data at shorter wavelengths with spectra recorded on the NIST 10.7m grating spectrograph (with phosphor image or photographic plates) and at longer wavelengths in the IR we use the NIST IR FT spectrometer.An elemental spectrum may contain thousands of spectral lines from the IR to VUV. We use these wavelengths to correct known atomic energy levels, and search for new atomic levels. The result is a classified linelist and accurate atomic energy levels.We present progress on iron group element atomic energy levels and wavelengths for V I and V II [2,3], Co III [4], Cr I, Mn I and Mn II, and Ni II.This work is supported by STFC(UK), The Leverhulme Trust, The Royal Society and NASA.References[1] Bergemann M, Pickering JC & Gehren T,“NLTE analysis of Co I/Co II lines in spectra of cool stars with new laboratory hyperfine splitting constants",MNRAS 401(2) 1334 (2010)[2] Thorne AP, Pickering JC & Semeniuk J,“The spectrum and term analysis of V II”, ApJS 207,13 (2013)[3] Thorne AP, Pickering JC & Semeniuk J,“The spectrum and term analysis of V I",ApJS 192,11 (2011)[4] Smillie DG

  17. WE-G-BRA-06: Calibrating an Ionisation Chamber: Gaining Experience Using a Dosimetry 'flight Simulator'.

    PubMed

    Beavis, A; Saunderson, J; Ward, J

    2012-06-01

    Recently there has been great interest in the use of simulation training, with the view to enhance safety within radiotherapy practice. We have developed a Virtual Environment for Radiotherapy Training (VERT) which facilitates this, including the simulation of a number of 'Physics practices'. One such process is the calibration of an ionisation chamber for use in Linac photon beams. The VERT system was used to provide a life sized 3D virtual environment within which we were able to simulate the calibration of a departmental chamber for 6MV and 15 MV beams following the UK 1990 Code of Practice. The characteristics of the beams are fixed parameters in the simulation, whereas default (Absorbed dose to water) correction factors of the chambers are configurable thereby dictating their response in the virtual x-ray beam. When the simulation is started, a random, realistic temperature and pressure is assigned to the bunker. Measurement and chamber positional errors are assigned to the chambers. A virtual water phantom was placed on the Linac couch and irradiated through the side using a 10 × 10 field. With a chamber at the appropriate depths and irradiated iso-centrically, the Quality Indices (QI) of the beams were obtained. The two chambers were 'inter-compared', allowing the departmental chamber calibration factor to be calculated from that of the reference chamber. For the virtual 6/15 MV beams, the QI were found to be 0.668/ 0.761 and the inter-comparison ratios 0.4408/ 0.4402 respectively. The departmental chamber calibration factors were calculated; applying these and appropriate environmental corrections allowed the output of the Linac to be confirmed. We have shown how a virtual training environment can be used to demonstrate practical processes and reinforce learning. The UK CoP was used here, however any relevant protocol could be demonstrated. Two of the authors (Beavis and Ward) are Founders of Vertual Ltd, a spin-out company created to commercialise the

  18. Addressing patient safety through the use of 'criteria of acceptability' for medical radiation equipment.

    PubMed

    Gilley, Debbie Bray; Holmberg, Ola

    2013-02-01

    Patient safety should be considered in the use of ionising radiation equipment in medicine. The International Atomic Energy Agency (IAEA) establishes standards of safety and provides for the application of these standards, also in the area of medical use of radiation. Equipment acceptability, as it relates to radiation in medicine, is the need to satisfy the requirements or standards prior to the use of the device in patient imaging or treatment. Through IAEA activities in establishing and developing Safety Standards, Safety Reports and recommendations to regulatory authorities and end-users, it encourages the adoption of acceptability criteria that are relevant to the medical equipment and its use.

  19. Determination of chlorinated paraffins in sediments from the Firth of Clyde by gas chromatography with electron capture negative ionisation mass spectrometry and carbon skeleton analysis by gas chromatography with flame ionisation detection.

    PubMed

    Hussy, Ines; Webster, Lynda; Russell, Marie; Moffat, Colin

    2012-07-01

    Short chain chlorinated paraffins (SCCPs) are a group of persistent organic pollutants (POPs) of increasing concern, but are to date not widely investigated in the environment, largely due to the challenges involved in their quantification. Here, SCCPs were quantified in marine sediments from the Firth of Clyde, Scotland, by gas chromatography with electron capture negative ionisation mass spectrometry (GC-ECNIMS) and through carbon skeleton analysis by gas chromatography with flame ionisation detection (GC-FID), and the analytical challenges encountered are discussed. Concentrations in the sediments ranged from 0.4 to 69 μg kg(-1) when determined by GC-ECNIMS, and from 5.6 to 379 μg kg(-1) when determined by GC-FID. For 8 out of 11 samples, analysis by GC-FID gave higher results than analysis by GC-ECNIMS. Unexpected aspects of the analysis, such as the presence of high concentrations of longer chain chlorinated paraffins in the samples, are also presented.

  20. Pelvic radiation therapy: Between delight and disaster

    PubMed Central

    Morris, Kirsten AL; Haboubi, Najib Y

    2015-01-01

    In the last few decades radiotherapy was established as one of the best and most widely used treatment modalities for certain tumours. Unfortunately that came with a price. As more people with cancer survive longer an ever increasing number of patients are living with the complications of radiotherapy and have become, in certain cases, difficult to manage. Pelvic radiation disease (PRD) can result from ionising radiation-induced damage to surrounding non-cancerous tissues resulting in disruption of normal physiological functions and symptoms such as diarrhoea, tenesmus, incontinence and rectal bleeding. The burden of PRD-related symptoms, which impact on a patient’s quality of life, has been under appreciated and sub-optimally managed. This article serves to promote awareness of PRD and the vast potential there is to improve current service provision and research activities. PMID:26649150