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Sample records for critical group icrp

  1. The work of the ICRP dose calculational task group: Issues in implementation of the ICRP dosimetric methodology

    SciTech Connect

    Eckerman, K.F.

    1999-01-01

    Committee 2 of the International Commission on Radiological Protection (ICRP) has had efforts underway to provide the radiation protection community with age-dependent dose coefficients, i.e.g, the dose per unit intake. The Task Group on Dose Calculations, chaired by the author, is responsible for the computation of these coefficients. The Task Group, formed in 1974 to produce ICRP Publication 30, is now international in its membership and its work load has been distributed among the institutions represented on the task group. This paper discusses: (1) recent advances in biokinetic modeling; (2) the recent changes in the dosimetric methodology; (3) the novel computational problems with some of the ICRP quantities; and (4) quality assurance issues which the Task Group has encountered. Potential future developments of the dosimetric framework which might strengthen the relationships with the emerging understanding of radiation risk will also be discussed.

  2. Report of the Task Group Calculations to ICRP Committee 2, October 14-17, 1980

    SciTech Connect

    Ford, M.R.

    1981-02-01

    This is the third in the series of reports of the Task Group on Dose Calculations to the International Commission on Radiological Protection (ICRP) Committee 2 as constituted for the four-year period 1977-1981. The two previous reports are documented in ORBL/TM-6988 (April 1979) and ORNL/TM-7230 (March 1980), respectively. Since the last meeting of the Committee, the Task Group has completed the computation of annual limit on intake (ALI) and derived air concentration (DAC) values and the corresponding supplemental data for 37 of the 43 elements planned for inclusion in the third and last part of the Committee report. The report entitled Limits for Intakes of Radionuclides by Workers, ICRP Publication 30 is being issued in three parts; and for each part, a supplement will be issued containing photocopied, computer-formatted supplemental data tables. Part 1 and the Supplement to Part 1 were both published in 1979, and the material for Part 2 and the Supplement to Part 2 are at Pergamon Press. Part 3 and Supplement will be ready for publication in 1981. The Task group plans to issue a separate report on radionuclide transformations used in estimating the ALI and DAC values in Publication 30. Preliminary data are being generated for this report, which will be timed to appear soon after the publication of Part 3 and the Supplement to Part 3.

  3. Report of ICRP Task Group 80: 'radiological protection in geological disposal of long-lived solid radioactive waste'.

    PubMed

    Weiss, W

    2012-01-01

    The report of International Commission on Radiological Protection (ICRP) Task Group 80 entitled 'Radiological protection in geological disposal of long-lived solid radioactive waste' updates and consolidates previous ICRP recommendations related to solid waste disposal (ICRP Publications 46, 77, and 81). The recommendations given in this report apply specifically to geological disposal of long-lived solid radioactive waste. The report explains how the 2007 system of radiological protection, described in ICRP Publication 103, can be applied in the context of the geological disposal of long-lived solid radioactive waste. The report is written as a self-standing document. It describes the different stages in the lifetime of a geological disposal facility, and addresses the application of relevant radiological protection principles for each stage depending on the various exposure situations that can be encountered. In particular, the crucial factor that influences application of the protection system over the different phases in the lifetime of a disposal facility is the level of oversight that is present. The level of oversight affects the capability to reduce or avoid exposures. Three main time frames have to be considered for the purpose of radiological protection: time of direct oversight when the disposal facility is being implemented and active oversight is taking place; time of indirect oversight when the disposal facility is sealed and indirect oversight is being exercised to provide additional assurance on behalf of the population; and time of no oversight when oversight is no longer exercised because memory is lost. Copyright © 2012. Published by Elsevier Ltd.

  4. Implications of the ICRP Task Group's proposed lung model for internal dose assessments in the mineral sands industry

    SciTech Connect

    James, A.C. ); Birchall, A. )

    1990-09-01

    The ICRP Task Group on Respiratory Tract Models for Radiological Projection is proposing a model to describe the deposition, clearance, retention and dosimetry of inhaled radionuclides for dose-intake calculations and interpretation of bioassay data. The deposition model takes into account new data on the regional deposition of aerosol particles in human lung and the inhalability of large particles. The clearance model treats clearance as competition between mechanical transport, which moves particles to the gastro-intestinal tract and lymph nodes, and the translocation of material to blood. This provides a realistic estimate of the amount of a given material (such as mineral sand) that is absorbed systemically, and its variation with aerosol size. The proposed dosimetry model takes into account the relative sensitivities of the various tissue components of the respiratory tract. A new treatment of dose received by epithelia in the tracheo-bronchiolar and extrathoracic regions is proposed. This paper outlines the novel features of the task group model, and then examines the impact that adoption of the model may have on the assessment of doses from occupational exposures to mineral sands and thoron progeny. 39 refs., 15 figs., 6 tabs.

  5. The respiratory tract deposition model proposed by the ICRP Task Group

    SciTech Connect

    James, A.C.; Briant, J.K. ); Stahlhofen, W.; Rudolf, G. . Abt. fuer Biophysikalische Strahlenforschung); Egan, M.J.; Nixon, W. ); Gehr, P. . Anatomisches Inst.)

    1990-11-01

    The Task Group has developed a new model of the deposition of inhaled aerosols in each anatomical region of the respiratory tract. The model is used to evaluate the fraction of airborne activity that is deposited in respiratory regions having distinct retention characteristics and clearance pathways: the anterior nares, the extrathoracic airways of the naso- and oropharynx and larynx, the bronchi, the bronchioles, and the alveolated airways of the lung. Drawn from experimental data on total and regional deposition in human subjects, the model is based on extrapolation of these data by means of a detailed theoretical model of aerosol transport and deposition within the lung. The Task Group model applies to all practical conditions, and for aerosol particles and vapors from atomic size up to very coarse aerosols with an activity median aerodynamic diameter of 100 {mu}m. The model is designed to predict regional deposition in different subjects, including adults of either sex, children of various ages, and infants, and also to account for anatomical differences among Caucasian and non-Caucasian subjects. The Task Group model represents aerosol inhalability and regional deposition in different subjects by algebraic expressions of aerosol size, breathing rates, standard lung volumes, and scaling factors for airway dimensions. 35 refs., 13 figs., 2 tabs.

  6. ICRP - What's happening

    SciTech Connect

    Meinhold, C.B.

    1982-01-01

    This paper discusses the goals of the ICRP for the 1980 decade in optimizing radiation protection in the areas of workers, patients, and the public. Economic and operational concerns are expressed. (PSB)

  7. Validation and verification of the ICRP biokinetic model of 32P: the criticality accident at Tokai-Mura, Japan.

    PubMed

    Miyamoto, K; Takeda, H; Nishimura, Y; Yukawa, M; Watanabe, Y; Ishigure, N; Kouno, F; Kuroda, N; Akashi, M

    2003-01-01

    Regrettably, a criticality accident occurred at a uranium conversion facility in Tokai-mura, Ibaraki, Japan, on 30 September 1999. Radioactivities of 32P in urine, blood and bone samples of the victims, who were severely exposed to neutrons, were measured. 32P was induced in their whole bodies at the moment of the first nuclear release by the reaction 31P (n, gamma) 32P and 32S (n, p) 32P. A realistic biokinetic model was assumed, as the exchange of 32P between the extracellular fluid compartment and the soft tissue compartment occurs only through the intracellular compartment, and the model was used for preliminary calculations. Some acute excretion of 32P, caused by decomposition or elution of tissues which occurred at the time of the accident, may have happened in the victims' bodies in the first few days. The working hypotheses in the present work should initiate renewed discussion of 32P biokinetics.

  8. Critical Thinking in Groups

    ERIC Educational Resources Information Center

    Harter, Nathan

    2009-01-01

    In his idea brief, Harter challenges us to examine the need for critical thinking in higher education and leadership studies, but in a considerably different manner than the lone reflective leader. The author suggests that no matter what the world might throw at them, graduates with this skill set would cope when a situation turns volatile,…

  9. Media Criticism Group Speech

    ERIC Educational Resources Information Center

    Ramsey, E. Michele

    2004-01-01

    Objective: To integrate speaking practice with rhetorical theory. Type of speech: Persuasive. Point value: 100 points (i.e., 30 points based on peer evaluations, 30 points based on individual performance, 40 points based on the group presentation), which is 25% of course grade. Requirements: (a) References: 7-10; (b) Length: 20-30 minutes; (c)…

  10. Translation of dose coefficients From ICRP 53 to ICRP 80.

    PubMed

    Moussa, Hanna M; Melanson, Mark A

    2013-02-01

    The effective dose coefficients tabulated in Publication 80 of the International Commission on Radiological Protection (ICRP) for the radiopharmaceuticals addressed earlier in ICRP Publication 53 are based on the tissue weighting factors of ICRP Publication 60. Presumably these values are derived from the tissue dose coefficients tabulated in Publication 53; however, no details regarding their derivation are provided. The tissue weighting factors of Publication 60 explicitly address tissue for which no dose coefficients were tabulated in Publication 53; for example, esophagus and a number of tissues comprising the remainder. In the absence of guidance, the authors have defined a set of rules for the translation and have undertaken an effort to derive the effective dose coefficients of Publication 80 starting with the organ/tissue dose coefficient of Publication 53.

  11. 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.

  12. Overview of ICRP Committee 5.

    PubMed

    Larsson, C-M; Higley, K A; Real, A

    2015-06-01

    The International Commission on Radiological Protection (ICRP) established Committee 5 in 2005 in response to the need to provide direct demonstration of environmental protection from radiation in accordance with national law and international agreements. The development of the ICRP system for environmental protection was facilitated by research over the previous decades, as well as by ICRP's evaluation of the ethical and philosophical basis for environmental protection as laid out in ICRP Publication 91. The 2007 Recommendations (Publication 103) incorporated environmental protection as one of the integral elements of the radiation protection system. Over a relatively short time, the system has evolved to incorporate a set of 12 Reference Animals and Plants (RAPs), which is a small enough number to develop comprehensive databases for each RAP, but wide ranging enough to provide some insight into radiation impact and protection against such impact, as appropriate, in terrestrial, freshwater, and marine ecosystems. As necessary, the databases can be used to derive supplementary databases for Representative Organisms typical for a particular exposure situation of concern or under study. The system, to date, details biology of the RAPs (Publication 108); outlines transfer factors for estimation of internal concentrations of radionuclides of environmental significance under different situations (Publication 114); provides further information (Publication 108) on dosimetry, biological effects, and derived consideration reference levels (bands of environmental dose rates where potential detrimental effects may deserve attention); and provides information on application of the system in planned, emergency, and existing exposure situations (Publication 124). Currently, a review of experimental determinations of relative biological effectiveness, to guide derivation of specific weighting factors for use in environmental radiation protection if possible and necessary, is

  13. Dosimetric methodology of the ICRP

    SciTech Connect

    Eckerman, K.F.

    1994-12-31

    Establishment of guidance for the protection of workers and members of the public from radiation exposures necessitates estimation of the radiation dose to tissues of the body at risk. The dosimetric methodology formulated by the International Commission on Radiological Protection (ICRP) is intended to be responsive to this need. While developed for radiation protection, elements of the methodology are often applied in addressing other radiation issues; e.g., risk assessment. This chapter provides an overview of the methodology, discusses its recent extension to age-dependent considerations, and illustrates specific aspects of the methodology through a number of numerical examples.

  14. Overview of ICRP Committee 4: application of the Commission's recommendations.

    PubMed

    Cool, D A

    2016-06-01

    Committee 4 develops principles and recommendations on radiological protection of people in all exposure situations. The committee meeting in 2014 was hosted by GE Healthcare in Arlington Heights, IL, USA on 27 July-1 August 2014. The programme of work of Committee 4 encompasses several broad areas, including a series of reports covering various aspects of existing exposure situations, leading the efforts of the International Commission on Radiological Protection (ICRP) to update and elaborate recommendations in light of the accident at Fukushima Daiichi nuclear power plant for emergencies and living in contaminated areas, elaborating the underpinnings of the system of radiological protection, and developing focussed reports on specific topic areas in consultation with ICRP's special liaison organisations. Committee 4 has six active Task Groups working on naturally occurring radioactive material; cosmic radiation in aviation; updates of ICRP Publications 109 and 111; ethics of radiological protection; surface and near-surface disposal of solid radioactive waste; and exposures resulting from contaminated sites from past industrial, military, and nuclear activities. In addition, there is a Working Party on tolerability of risk, and ongoing work with the various special liaison organisations of ICRP.

  15. Ethos in Fukushima and the ICRP dialogue seminars.

    PubMed

    Ando, R

    2016-01-01

    Ethos in Fukushima, a non-profit organisation, participated in 10 of the 12 International Commission on Radiological Protection (ICRP) dialogue seminars over the past 4 years. The slides and videos that were shown at the seminars are recorded on the Ethos in Fukushima website ( http://ethos-fukushima.blogspot.jp/p/icrp-dialogue.html ). I would like to introduce the activities of Ethos in Fukushima to date, and explain why the ICRP dialogue materials have come to be published on its website.

  16. Development of skeletal system for mesh-type ICRP reference adult phantoms

    NASA Astrophysics Data System (ADS)

    Yeom, Yeon Soo; Wang, Zhao Jun; Tat Nguyen, Thang; Kim, Han Sung; Choi, Chansoo; Han, Min Cheol; Kim, Chan Hyeong; Lee, Jai Ki; Chung, Beom Sun; Zankl, Maria; Petoussi-Henss, Nina; Bolch, Wesley E.; Lee, Choonsik

    2016-10-01

    The reference adult computational phantoms of the international commission on radiological protection (ICRP) described in Publication 110 are voxel-type computational phantoms based on whole-body computed tomography (CT) images of adult male and female patients. The voxel resolutions of these phantoms are in the order of a few millimeters and smaller tissues such as the eye lens, the skin, and the walls of some organs cannot be properly defined in the phantoms, resulting in limitations in dose coefficient calculations for weakly penetrating radiations. In order to address the limitations of the ICRP-110 phantoms, an ICRP Task Group has been recently formulated and the voxel phantoms are now being converted to a high-quality mesh format. As a part of the conversion project, in the present study, the skeleton models, one of the most important and complex organs of the body, were constructed. The constructed skeleton models were then tested by calculating red bone marrow (RBM) and endosteum dose coefficients (DCs) for broad parallel beams of photons and electrons and comparing the calculated values with those of the original ICRP-110 phantoms. The results show that for the photon exposures, there is a generally good agreement in the DCs between the mesh-type phantoms and the original voxel-type ICRP-110 phantoms; that is, the dose discrepancies were less than 7% in all cases except for the 0.03 MeV cases, for which the maximum difference was 14%. On the other hand, for the electron exposures (⩽4 MeV), the DCs of the mesh-type phantoms deviate from those of the ICRP-110 phantoms by up to ~1600 times at 0.03 MeV, which is indeed due to the improvement of the skeletal anatomy of the developed skeleton mesh models.

  17. Basis for the ICRP`s age-specific biokinetic model for uranium

    SciTech Connect

    Leggett, R.W.

    1994-12-01

    In an effort motivated largely by the Chernobyl nuclear accident, the International Commission on Radiological Protection (ICRP) is developing age-specific biokinetic models and dose coefficients for environmentally important radionuclides. This paper describes the ICRP`s age-specific biokinetic model for uranium. The model is constructed within a physiologically based framework originally developed for application to the alkaline earth elements but sufficiently general to apply to the larger class of bone-volume-seeking elements. Transfer rates for a reference adult are based mainly on: (1) measurements of uranium in blood and excreta of several human subjects who were intravenously injected with uranium; (2) postmortem measurements of uranium in tissues of some of those subjects; (3) postmortem measurements of uranium in tissues of occupationally and non-occupationally exposed subjects; (4) data on baboons, dogs, and smaller laboratory animals exposed to uranium for experimental purposes; and (5) consideration of the physiological processes thought to control retention and translocation of uranium in the body. Transfer rates for the adult are extended to children by application of a set of generic assumptions applied by the ICRP to calcium-like elements. These assumptions were derived mainly from observations of the age-specific biokinetics of the alkaline earth elements and lead in humans and laboratory animals but are consistent with available age-specific biokinetic data on uranium. 82 refs., 17 figs., 8 tabs.

  18. Strategic defensiveness: public and private responses to group criticism.

    PubMed

    Hornsey, Matthew J; Frederiks, Elisha; Smith, Joanne R; Ford, Lindsay

    2007-12-01

    This paper explores the strategic processes associated with responding to group criticism. In Experiment 1, Australians received criticism of their country from either an in-group or an out-group member. When participants believed their evaluations of the criticisms were private, they reported being more defensive when criticized by an out-group relative to an in-group member. However, this intergroup sensitivity effect disappeared on some measures when participants were led to believe their evaluations of the criticisms could be seen by an in-group audience. In Experiment 2, which focused on participants' identity as social science students, the attenuation of the intergroup sensitivity effect emerged only when the in-group audience was relatively high-status. Furthermore, in both experiments, increased reports of defensiveness in public only occurred in response to an in-group critic and not to an out-group critic. Theoretical and practical implications for intergroup and intragroup communication are discussed.

  19. Critical Issues in International Group Counseling

    ERIC Educational Resources Information Center

    Bemak, Fred; Chung, Rita Chi-Ying

    2015-01-01

    Three-quarters of the world come from collectivistic group-oriented cultures. As the world becomes more globalized it is inevitable that group counseling will be a major choice of healing and psychological intervention internationally. However, a review of scholarly articles from "The Journal for Specialists in Group Work" and…

  20. Critical Issues in International Group Counseling

    ERIC Educational Resources Information Center

    Bemak, Fred; Chung, Rita Chi-Ying

    2015-01-01

    Three-quarters of the world come from collectivistic group-oriented cultures. As the world becomes more globalized it is inevitable that group counseling will be a major choice of healing and psychological intervention internationally. However, a review of scholarly articles from "The Journal for Specialists in Group Work" and…

  1. Management of radon: a review of ICRP recommendations.

    PubMed

    Vaillant, Ludovic; Bataille, Céline

    2012-09-01

    This article proposes a review of past and current ICRP publications dealing with the management of radon exposures. Its main objective is to identify and discuss the driving factors that have been used by the Commission during the last 50 years so as to better appreciate current issues regarding radon exposure management. The analysis shows that major evolutions took place in very recent years. As far as the management of radon exposures is concerned, ICRP recommended, until ICRP Publication 103 (ICRP 2007 ICRP Publication 103; Ann. ICRP 37), to use action levels and to consider only exposures above these levels. The Commission has reviewed its approach and now proposes to manage any radon exposure through the application of the optimisation principle and associated reference levels. As far as the assessment of the radon risk is concerned, it appears that the successive changes made by ICRP did not have a strong impact on the values of radon gas concentration recommended as action levels either in dwellings or in workplaces. The major change occurred in late 2009 with the publication of the ICRP Statement on Radon, which acknowledged that the radon risk has been underestimated by a factor of 2, thus inducing a major revision of radon reference levels.

  2. Comparison of the ICRP and MIRD models for Fe metabolism in man.

    PubMed

    Johnson, J R; Dunford, D W

    1985-08-01

    A task group of the Medical Internal Radiation Dose (MIRD) Committee has recently published a model of Fe metabolism in man. This model was developed to calculate doses from radioiron injected for medical diagnostic purposes. It is a compartment model with recirculating Fe exchanging between plasma and extracellular fluids, tissue storage compartments, bone marrow and red blood cells (RBC). It is a first order model with the exception of Fe in the RBC compartment, which is assumed to retain Fe for 120 days, at which time the Fe returns to the extracellular fluid compartment. By contrast, the International Commission on Radiological Protection (ICRP) model is a "once through" first order compartment model, with the compartments represented by organs (spleen, liver and other soft tissue) rather than physiological compartments as in the MIRD model. Both of these models have been implemented in the computer code GENMOD which contains the ICRP recommended lung and gastrointestinal tract models and which is used at the Chalk River Nuclear Laboratories to calculate doses, excretion rates, derived investigation levels, etc. The results of calculations using these models have been compared to see if the much less sophisticated ICRP model was adequate for radiation protection purposes. It was found that the effective dose per unit intake of radioiron was higher for the MIRD model and urinary excretion rates following an exposure were considerably different. It is concluded that the ICRP model should not be used in dosimetry calculations, or for comparing monitoring results to model calculations.

  3. Groups concerned about Congress and criticism

    SciTech Connect

    Lucas, A.

    1994-12-07

    Environmental groups are concerned about the impact a Republican-dominated Congress will have on their activities. The Republican agenda would {open_quotes}severely undercut public health and environmental protection, {close_quotes} says the Natural Resources Defense Council (NRDC; Washington).

  4. Is ICRP guidance on the use of reference levels consistent?

    PubMed

    Hedemann-Jensen, Per; McEwan, Andrew C

    2011-12-01

    In ICRP 103, which has replaced ICRP 60, it is stated that no fundamental changes have been introduced compared with ICRP 60. This is true except that the application of reference levels in emergency and existing exposure situations seems to be applied inconsistently, and also in the related publications ICRP 109 and ICRP 111. ICRP 103 emphasises that focus should be on the residual doses after the implementation of protection strategies in emergency and existing exposure situations. If possible, the result of an optimised protection strategy should bring the residual dose below the reference level. Thus the reference level represents the maximum acceptable residual dose after an optimised protection strategy has been implemented. It is not an 'off-the-shelf item' that can be set free of the prevailing situation. It should be determined as part of the process of optimising the protection strategy. If not, protection would be sub-optimised. However, in ICRP 103 some inconsistent concepts have been introduced, e.g. in paragraph 279 which states: 'All exposures above or below the reference level should be subject to optimisation of protection, and particular attention should be given to exposures above the reference level'. If, in fact, all exposures above and below reference levels are subject to the process of optimisation, reference levels appear superfluous. It could be considered that if optimisation of protection below a fixed reference level is necessary, then the reference level has been set too high at the outset. Up until the last phase of the preparation of ICRP 103 the concept of a dose constraint was recommended to constrain the optimisation of protection in all types of exposure situations. In the final phase, the term 'dose constraint' was changed to 'reference level' for emergency and existing exposure situations. However, it seems as if in ICRP 103 it was not fully recognised that dose constraints and reference levels are conceptually different. The

  5. The future of ICRP: towards a centenary and beyond.

    PubMed

    Cousins, C

    2016-06-01

    The International Commission on Radiological Protection (ICRP) has been in existence for 87 y, since its establishment in 1928. It remains a leading authority in radiological protection, and its role is to provide recommendations and guidance on all aspects of protection against ionising radiation. The published recommendations of ICRP form the basis of radiation safety standards worldwide. Modernisation of the organisation in recent years has led to new initiatives and changes. These have included writing a strategic plan and code of ethics for the first time. Elections for committee membership have been through open nominations, a process which will shortly be repeated for the membership in the next term, commencing on 1 July 2017. Biennial symposia started in 2011, and the success of the first two symposia has secured this venture as a regular part of the ICRP calendar. ICRP has also revised its method of working with other organisations by establishing 'special liaison organisation' status. This has improved collaboration with the ever-expanding number of organisations working in radiological protection, with whom it is important that ICRP has essential links. ICRP is also looking to review its legal basis and governing documents in the future, in order to ensure that best practices are being followed as ICRP evolves. In addition, the strategic plan will be reviewed and updated regularly. Other ways of working with organisations will be considered to further strengthen engagement with the wider radiological protection community. ICRP aims to make its publications available at low or no cost, and to produce both a plain language overview of the system of radiological protection and a summary of the recommendations. These activities will require additional financial resources, and ICRP has embarked on a fundraising campaign to support such efforts. ICRP can be proud of its history of maintaining its independence and preserving the wide respect earned over many

  6. Synchrotron radiation shielding design and ICRP radiological protection quantities.

    PubMed

    Bassey, Bassey; Moreno, Beatriz; Chapman, Dean

    2015-06-01

    Protection and operational quantities as defined by the International Commission on Radiological Protection (ICRP) and the International Commission on Radiation Units and Measurements (ICRU) are the two sets of quantities recommended for use in radiological protection for external radiation. Since the '80s, the protection quantities have evolved from the concept of dose equivalent to effective dose equivalent to effective dose, and the associated conversion coefficients have undergone changes. In this work, the influence of three different versions of ICRP photon dose conversion coefficients in the synchrotron radiation shielding calculations of an experimental enclosure has been examined. The versions are effective dose equivalent (ICRP Publication 51), effective dose (ICRP Publication 74), and effective dose (ICRP Publication 116) conversion coefficients. The sources of the synchrotron radiation white beam into the enclosure were a bending magnet, an undulator and a wiggler. The ranges of photons energy from these sources were 10-200 keV for the bending magnet and undulator, and 10-500 keV for the wiggler. The design criterion aimed a radiation leakage less than 0.5 µSv h(-1) from the enclosure. As expected, larger conversion coefficients in ICRP Publication 51 lead to higher calculated dose rates. However, the percentage differences among the calculated dose rates get smaller once shielding is added, and the choice of conversion coefficients set did not affect the final shielding decision.

  7. Current activities in the ICRP concerning estimation of radiation doses to patients from radiopharmaceuticals for diagnostic use

    NASA Astrophysics Data System (ADS)

    Mattsson, S.; Johansson, L.; Leide-Svegborn, S.; Liniecki, J.; Nosske, D.; Riklund, K.; Stabin, M.; Taylor, D.

    2011-09-01

    A Task Group within the ICRP Committees 2 and 3 is continuously working to improve absorbed dose estimates to patients investigated with radiopharmaceuticals. The work deals with reviews of the literature, initiation of new or complementary studies of the biokinetics of a compound and dose estimates. Absorbed dose calculations for organs and tissues have up to now been carried out using the MIRD formalism. There is still a lack of necessary biokinetic data from measurements in humans. More time series obtained by nuclear medicine imaging techniques such as whole-body planar gamma-camera imaging, SPECT or PET are highly desirable for this purpose. In 2008, a new addendum to ICRP Publication 53 was published under the name of ICRP Publication 106 containing biokinetic data and absorbed dose information to organs and tissues of patients of various ages for radiopharmaceuticals in common use. That report also covers a number of generic models and realistic maximum models covering other large groups of substances (e.g. "123I-brain receptor substances"). Together with ICRP Publication 80, most radiopharmaceuticals in clinical use at the time of publication were covered except the radioiodine labeled compounds for which the ICRP dose estimates are still found in Publication 53. There is an increasing use of new radiopharmaceuticals, especially PET-tracers and the TG has recently finished its work with biokinetic and dosimetric data for 18F-FET, 18F-FLT and 18F-choline. The work continues now with new data for 11C-raclopride, 11C-PiB and 123I-ioflupan as well as re-evaluation of published data for 82Rb-chloride, 18F-fluoride and radioiodide. This paper summarises published ICRP-information on dose to patients from radiopharmaceuticals and gives some preliminary data for substances under review.

  8. Differences among Course Grade Groups on Critical Thinking.

    ERIC Educational Resources Information Center

    Gadzella, Bernadette M.; And Others

    This study compared critical thinking skills of 98 college freshmen as measured by the Watson-Glaser Critical Thinking Appraisal instrument during their first week in the course with their final grades in a freshman course. Results indicated that there were significant differences among the three groups on the three subtests of Inference,…

  9. The Psychology of Groups: Why Quality and Impartial Leadership Is Critical to a Group's Success.

    ERIC Educational Resources Information Center

    Campbell, Richard

    Many decisions made by outdoor leaders are critical to the well-being of an entire group. Understanding the psychology of groups is important to successful leadership. This paper presents ways that individuals are motivated in groups, how groups respond, some symptoms of problems, and strategies to divert problems that can overwhelm a group.…

  10. The Psychology of Groups: Why Quality and Impartial Leadership Is Critical to a Group's Success.

    ERIC Educational Resources Information Center

    Campbell, Richard

    Many decisions made by outdoor leaders are critical to the well-being of an entire group. Understanding the psychology of groups is important to successful leadership. This paper presents ways that individuals are motivated in groups, how groups respond, some symptoms of problems, and strategies to divert problems that can overwhelm a group.…

  11. Comparisons of calculated respiratory tract deposition of particles based on the NCRP/ITRI model and the new ICRP66 model

    SciTech Connect

    Yeh, Hsu-Chi; Phalen, R.F.; Chang, I.

    1995-12-01

    The National Council on Radiation Protection and Measurements (NCRP) in the United States and the International Commission on Radiological Protection (ICRP) have been independently reviewing and revising respiratory tract dosimetry models for inhaled radioactive aerosols. The newly proposed NCRP respiratory tract dosimetry model represents a significant change in philosophy from the old ICRP Task Group model. The proposed NCRP model describes respiratory tract deposition, clearance, and dosimetry for radioactive substances inhaled by workers and the general public and is expected to be published soon. In support of the NCRP proposed model, ITRI staff members have been developing computer software. Although this software is still incomplete, the deposition portion has been completed and can be used to calculate inhaled particle deposition within the respiratory tract for particle sizes as small as radon and radon progeny ({approximately} 1 nm) to particles larger than 100 {mu}m. Recently, ICRP published their new dosimetric model for the respiratory tract, ICRP66. Based on ICRP66, the National Radiological Protection Board of the UK developed PC-based software, LUDEP, for calculating particle deposition and internal doses. The purpose of this report is to compare the calculated respiratory tract deposition of particles using the NCRP/ITRI model and the ICRP66 model, under the same particle size distribution and breathing conditions. In summary, the general trends of the deposition curves for the two models were similar.

  12. Critical Reflections: How Groups Can Learn from Success and Failure

    ERIC Educational Resources Information Center

    Ernst, Chris; Martin, Andre

    2006-01-01

    When people work together over time, certain key events stand out as having the potential to teach lasting lessons for the future. Leaders can use the Critical Reflections process to help their groups learn these lessons, whether the key event was a great success or a wretched failure. The goal is to affect future outcomes in similar situations:…

  13. Critical Friends Group for EFL Teacher Professional Development

    ERIC Educational Resources Information Center

    Vo, Long Thanh; Nguyen, Hoa Thi Mai

    2010-01-01

    For the best student outcomes, teachers need to engage in continuous professional development. As a result, models of teacher professional development have been developed, among which is the Critical Friends Group (CFG) technique. However, whether it works well with EFL teachers in an Asian context like Vietnam, where EFL teachers in particular do…

  14. Critical Friends Group for EFL Teacher Professional Development

    ERIC Educational Resources Information Center

    Vo, Long Thanh; Nguyen, Hoa Thi Mai

    2010-01-01

    For the best student outcomes, teachers need to engage in continuous professional development. As a result, models of teacher professional development have been developed, among which is the Critical Friends Group (CFG) technique. However, whether it works well with EFL teachers in an Asian context like Vietnam, where EFL teachers in particular do…

  15. ICRP, 123. Assessment of radiation exposure of astronauts in space. ICRP Publication 123.

    PubMed

    Dietze, G; Bartlett, D T; Cool, D A; Cucinotta, F A; Jia, X; McAulay, I R; Pelliccioni, M; Petrov, V; Reitz, G; Sato, T

    2013-08-01

    During their occupational activities in space, astronauts are exposed to ionising radiation from natural radiation sources present in this environment. They are, however, not usually classified as being occupationally exposed in the sense of the general ICRP system for radiation protection of workers applied on Earth. The exposure assessment and risk-related approach described in this report is clearly restricted to the special situation in space, and should not be applied to any other exposure situation on Earth. The report describes the terms and methods used to assess the radiation exposure of astronauts, and provides data for the assessment of organ doses. Chapter 1 describes the specific situation of astronauts in space, and the differences in the radiation fields compared with those on Earth. In Chapter 2, the radiation fields in space are described in detail, including galactic cosmic radiation, radiation from the Sun and its special solar particle events, and the radiation belts surrounding the Earth. Chapter 3 deals with the quantities used in radiological protection, describing the Publication 103 (ICRP, 2007) system of dose quantities, and subsequently presenting the special approach for applications in space; due to the strong contribution of heavy ions in the radiation field, radiation weighting is based on the radiation quality factor, Q, instead of the radiation weighting factor, wR. In Chapter 4, the methods of fluence and dose measurement in space are described, including instrumentation for fluence measurements, radiation spectrometry, and area and individual monitoring. The use of biomarkers for the assessment of mission doses is also described. The methods of determining quantities describing the radiation fields within a spacecraft are given in Chapter 5. Radiation transport calculations are the most important tool. Some physical data used in radiation transport codes are presented, and the various codes used for calculations in high

  16. Overview of ICRP Committee 5: protection of the environment.

    PubMed

    Larsson, C-M

    2016-06-01

    Protection of the environment is integral to the system of radiological protection, as outlined in the 2007 Recommendations of the International Commission on Radiological Protection (ICRP, Publication 103). The Commission's activities in this area are mainly pursued by Committee 5 and its associated Task Groups. Publication 91 broadly outlines the approach to radiological protection of the environment, and its alignment with approaches to environmental protection from hazardous substances in general. Publications 108 and 114 provide the cornerstones of the environmental protection system and relevant databases. Publication 124 considers its application in planned, existing, and emergency exposure situations. The system centres on 12 Reference Animals and Plants (RAPs) with broad relevance for environmental protection based on their ubiquity and significance as well as other criteria, as described in Publication 108 The databases comprise general biology of the RAPs, transfer parameters, dose conversion coefficients, and effects data. Derived Consideration Reference Levels (DCRLs) were established for each RAP; a DCRL represents a band of dose rates that might result in some deleterious effects in individuals of that type of RAP. Newly established Task Group 99 will compile the RAP-specific reference information into monographs, with the view of updating information and improving the applicability of the system in different exposure situations. For certain scenarios, more precise and ecosystem-specific protection benchmarks may be justified, which would have to be informed by consideration of representative organisms (i.e. representative of a particular ecosystem and relevant to the specific scenario; Publication 124). Committee 5 will explore this further, making use of a limited number of case studies.

  17. Critical asymmetry in renormalization group theory for fluids.

    PubMed

    Zhao, Wei; Wu, Liang; Wang, Long; Li, Liyan; Cai, Jun

    2013-06-21

    The renormalization-group (RG) approaches for fluids are employed to investigate critical asymmetry of vapour-liquid equilibrium (VLE) of fluids. Three different approaches based on RG theory for fluids are reviewed and compared. RG approaches are applied to various fluid systems: hard-core square-well fluids of variable ranges, hard-core Yukawa fluids, and square-well dimer fluids and modelling VLE of n-alkane molecules. Phase diagrams of simple model fluids and alkanes described by RG approaches are analyzed to assess the capability of describing the VLE critical asymmetry which is suggested in complete scaling theory. Results of thermodynamic properties obtained by RG theory for fluids agree with the simulation and experimental data. Coexistence diameters, which are smaller than the critical densities, are found in the RG descriptions of critical asymmetries of several fluids. Our calculation and analysis show that the approach coupling local free energy with White's RG iteration which aims to incorporate density fluctuations into free energy is not adequate for VLE critical asymmetry due to the inadequate order parameter and the local free energy functional used in the partition function.

  18. Cancer support groups: a critical review of empirical studies.

    PubMed

    Gottlieb, Benjamin H; Wachala, Elizabeth D

    2007-05-01

    Support groups for adults affected by cancer are widely offered by local community and national agencies in North America. This type of psychosocial intervention is defined in terms of its structure and functions, and its theoretical underpinnings and models of practice are described. Forty-four empirical studies of professionally led cancer support groups are summarized and critically reviewed. These studies include 32 outcome evaluations of randomized controlled trials, two process evaluations, and 10 consumer satisfaction studies. The findings reveal high levels of consumer satisfaction, and the outcome evaluations substantiate the morale and other quality of life benefits short of prolonging life. Discussion centers on priorities for future research and practice.

  19. The revised International Commission on Radiological Protection (ICRP) dosimetric model for the human respiratory tract

    SciTech Connect

    Bair, W.J.

    1992-05-01

    A task group has revised the dosimetric model of the respiratory tract used to calculate annual limits on intake of radionuclides. The revised model can be used to project respiratory tract doses for workers and members of the public from airborne radionuclides and to assess past exposures. Doses calculated for specific extrathoracic and thoracic tissues can be adjusted to account for differences in radiosensitivity and summed to yield two values of dose for the respiratory tract that are applicable to the ICRP tissue weighted dosimetry system.

  20. Improved renormalization group theory for critical asymmetry of fluids.

    PubMed

    Wang, Long; Zhao, Wei; Wu, Liang; Li, Liyan; Cai, Jun

    2013-09-28

    We develop an improved renormalization group (RG) approach incorporating the critical vapor-liquid equilibrium asymmetry. In order to treat the critical asymmetry of vapor-liquid equilibrium, the integral measure is introduced in the Landau-Ginzbug partition function to achieve a crossover between the local order parameter in Ising model and the density of fluid systems. In the implementation of the improved RG approach, we relate the integral measure with the inhomogeneous density distribution of a fluid system and combine the developed method with SAFT-VR (statistical associating fluid theory of variable range) equation of state. The method is applied to various fluid systems including square-well fluid, square-well dimer fluid and real fluids such as methane (CH4), ethane (C2H6), trifluorotrichloroethane (C2F3Cl3), and sulfur hexafluoride (SF6). The descriptions of vapor-liquid equilibria provided by the developed method are in excellent agreement with simulation and experimental data. Furthermore, the improved method predicts accurate and qualitatively correct behavior of coexistence diameter near the critical point and produces the non-classical 3D Ising criticality.

  1. Criticality triggers the emergence of collective intelligence in groups

    NASA Astrophysics Data System (ADS)

    De Vincenzo, Ilario; Giannoccaro, Ilaria; Carbone, Giuseppe; Grigolini, Paolo

    2017-08-01

    A spinlike model mimicking human behavior in groups is employed to investigate the dynamics of the decision-making process. Within the model, the temporal evolution of the state of systems is governed by a time-continuous Markov chain. The transition rates of the resulting master equation are defined in terms of the change of interaction energy between the neighboring agents (change of the level of conflict) and the change of a locally defined agent fitness. Three control parameters can be identified: (i) the social interaction strength β J measured in units of social temperature, (ii) the level of confidence β' that each individual has on his own expertise, and (iii) the level of knowledge p that identifies the expertise of each member. Based on these three parameters, the phase diagrams of the system show that a critical transition front exists where a sharp and concurrent change in fitness and consensus takes place. We show that at the critical front, the information leakage from the fitness landscape to the agents is maximized. This event triggers the emergence of the collective intelligence of the group, and in the end it leads to a dramatic improvement in the decision-making performance of the group. The effect of size M of the system is also investigated, showing that, depending on the value of the control parameters, increasing M may be either beneficial or detrimental.

  2. Application of the ICRP clarification of the tritium metabolic model.

    PubMed

    Potter, Charles A

    2004-10-01

    In 2001, the International Commission on Radiological Protection published a clarification to the model for tritium metabolism. This clarification described the use of the gastrointestinal tract model, respiratory tract model, and transfer compartment in calculations of tritium metabolism. This information was used to derive intake retention fractions for tritium and tritium compounds including tritiated water, organically bound tritium, and tritides. In addition, dose coefficients were derived for tritide compounds including general categories described by the ICRP and some specific compounds.

  3. Revision of the ICRP dosimetric model for the human respiratory tract

    SciTech Connect

    Bair, W.J.

    1990-12-01

    Although the dosimetric model of the respiratory tract used in ICRP Publication 30 had not been shown to be seriously deficient for the purpose of calculating Annual Limits on Intake (ALIs) for workers, the availability of new information led the ICRP in 1984 to create a special Task Group to review the dosimetric model of the respiratory tract and, if justified, propose revisions or a new model. The Task Group directed its efforts toward improving the model used in Publication 30 rather than developing a completely new model. The objective was a model that would facilitate calculation of biologically meaningful doses; be consistent with morphological, physiological, and radiobiological characteristics of the respiratory tract; incorporate current knowledge; meet all radiation protection needs; be user friendly by not being unnecessarily sophisticated; be adaptable to development of computer software for calculation of relevant radiation doses from knowledge of a few readily measured exposure parameters; be equally useful for assessment purposes as for calculating ALIs; be applicable to all members of the world population; and consider the influence of smoking, air pollutants, and diseases of the inhalation, deposition, and clearance of radioactive particles from the respiratory tract. The model provides for calculation of a committed dose equivalent for each region, adjusted for the relative cancer sensitivity of that region, and for the summing of these to yield a committed dose equivalent for the entire respiratory tract. 3 figs.

  4. Validating an important aspect of the new ICRP biokinetic model of thorium.

    PubMed

    Roth, P; Höllriegl, V; Li, W B; Oeh, U; Schramel, P

    2005-03-01

    The daily urinary excretion of Th (Th) was estimated in 11 adult German subjects who were not exposed occupationally to thorium and its related compounds. Thirty-one urine samples were collected over 24-h periods on different occasions from these subjects and were analyzed using high resolution sector field inductively coupled plasma mass spectrometry (HR-SF-ICP-MS). Using this instrument a limit of detection of 20 pg L for thorium in the reagent blank was achieved. The median (mean) daily urinary thorium excretion was obtained as 1.0 (1.8) ng. This was in good agreement with the mean value of 1.5 ng Th (6 microBq) reported by another group for German population, but is significantly lower in comparison to the daily excretion range of 3.6 to 105 ng reported from other countries. The expected daily urinary excretion of thorium for the adult German population was also calculated by applying the new ICRP biokinetic model of thorium assuming reference intake values. The expected urinary thorium excretion rate for this age group is about 0.1 ng per day. Even if a small contribution from the inhalation is considered, the calculated value will be much lower than the measured values. The reason for the disagreement appears to be the use of a low gastrointestinal absorption factor (f1) of 5 x 10 in the ICRP model. Based on the present study, a higher f1 factor might be proposed separately for dietary incorporated thorium.

  5. Accounting for care: Healthcare Resource Groups for paediatric critical care.

    PubMed

    Murphy, Janet; Morris, Kevin

    2008-02-01

    Healthcare Resource Groups are a way of grouping patients in relation to the amount of healthcare resources they consume. They are the basis for implementation of Payment by Results by the Department of Health in England. An expert working group was set up to define a dataset for paediatric critical care that would in turn support the derivation of Healthcare Resource Groups. Three relevant classification systems were identified and tested with data from ten PICUs, including data about diagnoses, number of organ systems supported, interventions and nursing activity. Each PICU provided detailed costing for the financial year 2005/2006. Eighty-three per cent of PICU costs were found to be related to staff costs, with the largest cost being nursing costs. The Nursing Activity Score system was found to be a poor predictor of staff resource use, as was the adult HRG model based on the number of organ systems supported. It was decided to develop the HRGs based on a 'levels of care' approach; 32 data items were defined to support HRG allocation. From October 2007, data have been collected daily to identify the HRGs for each PICU patient and are being used by the Department of Health to estimate reference costs for PICU services. The data can also be used to support improved audit of PICU activity nationally as well as comparison of workload across different units and modelling of staff requirements within a unit.

  6. Sugaring the Pill: Assessing Rhetorical Strategies Designed to Minimize Defensive Reactions to Group Criticism

    ERIC Educational Resources Information Center

    Hornsey, Matthew J.; Robson, Erin; Smith, Joanne; Esposo, Sarah; Sutton, Robbie M.

    2008-01-01

    People are considerably more defensive in the face of group criticism when the criticism comes from an out-group rather than an in-group member (the intergroup sensitivity effect). We tested three strategies that out-group critics can use to reduce this heightened defensiveness. In all studies, Australians received criticism of their country…

  7. Application of the proposed new ICRP lung model to bioassay

    SciTech Connect

    Johnson, J.R.; James, A.C.; Hill, R.L.

    1992-05-01

    The new lung model being proposed by ICRP for use in radiation protection dosimetry requires the calculation of doses to separate regions of the respiratory tract, multiplying these doses by factors proportional to the risk per unit dose to each region, and summing over all regions of the lung to give a ``weighted`` lung dose. This paper compares the doses that would be calculated form bioassay measurements using the new model with those calculated using the current model, which essentially uses total lung burden to estimate lung dose.

  8. Application of the proposed new ICRP lung model to bioassay

    SciTech Connect

    Johnson, J.R.; James, A.C.; Hill, R.L.

    1992-05-01

    The new lung model being proposed by ICRP for use in radiation protection dosimetry requires the calculation of doses to separate regions of the respiratory tract, multiplying these doses by factors proportional to the risk per unit dose to each region, and summing over all regions of the lung to give a weighted'' lung dose. This paper compares the doses that would be calculated form bioassay measurements using the new model with those calculated using the current model, which essentially uses total lung burden to estimate lung dose.

  9. ICRP Publication 107. Nuclear decay data for dosimetric calculations.

    PubMed

    Eckerman, K; Endo, A

    2008-01-01

    In this report, the Commission provides an electronic database of the physical data needed in calculations of radionuclide-specific protection and operational quantities. This database supersedes the data of Publication 38 (ICRP, 1983), and will be used in future ICRP publications of dose coefficients for the intake of or exposure to radionuclides in the workplace and the environment.The database contains information on the half-lives, decay chains, and yields and energies of radiations emitted in nuclear transformations of 1252 radionuclides of 97 elements. The CD accompanying the publication provides electronic access to complete tables of the emitted radiations, as well as the beta and neutron spectra. The database has been constructed such that user-developed software can extract the data needed for further calculations of a radionuclide of interest. A Windows-based application is provided to display summary information on a user-specified radionuclide, as well as the general characterisation of the nuclides contained in the database. In addition, the application provides a means by which the user can export the emissions of a specified radionuclide for use in subsequent calculations.

  10. Comparison of observed skeleton retention of strontium in average indian adult with the value predicted by the ICRP biokinetic model.

    PubMed

    Nair, Suma; Pradhan, A S; Jaiswal, D D; Singh, I S; Garg, S P

    2006-01-01

    The daily dietary intake of strontium and its content in skeleton, for an Indian adult population group were estimated by experimentally measuring its concentration in total cooked diet and autopsy skeleton samples using radiochemical neutron activation analysis. The data on daily dietary intake of strontium were used to compute its contents in skeleton using ICRP Publication 67 biokinetic model for strontium. The theoretically computed value of strontium (213.8 mg) compared favourably with the measured values (GM 181.2 mg) in an urban population group living in Mumbai representing an average Indian adult (Reference Indian Man).

  11. The critical discussion group: fostering personal and scientific growth.

    PubMed

    Klein, Allon M; Lande-Diner, Laura

    2011-10-21

    As scientists, we greatly benefit from discussing our work with our peers. Informal, unstructured interactions often yield highly creative feedback. With this in mind, we created a group that fosters discussion of its members' work. The group engages us in new research fields and ways of thinking, and provides us with an opportunity for co-mentoring. Three key components were essential for making this group work: the emphasis on non-hierarchical debate; the diversity of the group members; and the mutual respect existing among the participants. Copyright © 2011 Elsevier Inc. All rights reserved.

  12. Cooperative Learning: A Critical Analysis of the Group Investigation Model.

    ERIC Educational Resources Information Center

    Saban, Ahmet

    1994-01-01

    Explains cooperative learning and provides a sample implementation of the group investigation model. Suggests that implementation of the group investigation model in a graduate-level reading education course supports the findings of cooperative learning in the literature. Argues that cooperative learning should be a part of teacher education…

  13. X-ray population exposure from projection radiology and computed tomography in Emilia-Romagna from 2001 to 2010: comparison of ICRP 60 and ICRP 103 weighting factors.

    PubMed

    Compagnone, Gaetano; Angelini, Paola; Domenichelli, Sara

    2014-05-01

    This paper shows the trends from 2001 to 2010 of per caput and collective effective dose (S) to the Emilia-Romagna population due to radiation exposure from projection radiology (PR) and computed tomography (CT), calculated according to both ICRP60 and ICRP103 tissue weighting factors. The frequency of examinations and dose calculations were based on data provided directly by Emilia-Romagna Health Trusts. In particular, effective doses were evaluated using the tissue weighting (w T) factors reported both in ICRP60 (w T,60) and in ICRP103 (w T,103). A decrease in the frequency of PR skull examinations and an increase in the frequency of mammography, CT of the abdomen, chest, and head-neck were found during the decade. In 2010, the PR/CT procedures contributed 75.4 %/24.6 % to examination frequency and approximately 10 %/90 % to dose; S was 6,169.2 man Sv when w T,60 was used and 5,855.1-6,665.5 man Sv when w T,103 in two different mathematical models was utilised. Dose estimates pre- and post-ICRP103 must be compared carefully, because changes due to different radiological practices could be confused with changes due to the use of different w T's. In general, dose evaluations with the use of w T,60 until 2007 and w T,103 from 2008 seem to be consistent and coherent.

  14. User's manual to the ICRP Code: a series of computer programs to perform dosimetric calculations for the ICRP Committee 2 report

    SciTech Connect

    Watson, S.B.; Ford, M.R.

    1980-02-01

    A computer code has been developed that implements the recommendations of ICRP Committee 2 for computing limits for occupational exposure of radionuclides. The purpose of this report is to describe the various modules of the computer code and to present a description of the methods and criteria used to compute the tables published in the Committee 2 report. The computer code contains three modules of which: (1) one computes specific effective energy; (2) one calculates cumulated activity; and (3) one computes dose and the series of ICRP tables. The description of the first two modules emphasizes the new ICRP Committee 2 recommendations in computing specific effective energy and cumulated activity. For the third module, the complex criteria are discussed for calculating the tables of committed dose equivalent, weighted committed dose equivalents, annual limit of intake, and derived air concentration.

  15. The Influence of Collaborative Group Work on Students' Development of Critical Thinking: The Teacher's Role in Facilitating Group Discussions

    ERIC Educational Resources Information Center

    Fung, Dennis Chun-Lok; To, Helen; Leung, Kit

    2016-01-01

    The objective of this study was to determine whether the incorporation of group work in a teaching intervention can effectively foster students' critical thinking skills. Building upon Kuhn's critical thinking model, the research involved comparison of pretest and post-test results for 140 secondary four (10th grade) students in Hong Kong on two…

  16. The Influence of Collaborative Group Work on Students' Development of Critical Thinking: The Teacher's Role in Facilitating Group Discussions

    ERIC Educational Resources Information Center

    Fung, Dennis Chun-Lok; To, Helen; Leung, Kit

    2016-01-01

    The objective of this study was to determine whether the incorporation of group work in a teaching intervention can effectively foster students' critical thinking skills. Building upon Kuhn's critical thinking model, the research involved comparison of pretest and post-test results for 140 secondary four (10th grade) students in Hong Kong on two…

  17. Evaluation of absorbed and effective doses to patients from radiopharmaceuticals using the ICRP 110 reference computational phantoms and ICRP 103 formulation.

    PubMed

    Hadid, Lama; Gardumi, Anna; Desbrée, Aurélie

    2013-09-01

    In diagnostic nuclear medicine, mean absorbed doses to patients' organs and effective doses are published for standard stylised anatomic models. To provide more realistic and detailed geometries of the human morphology, the International Commission on Radiological Protection (ICRP) has recently adopted male and female voxel phantoms to represent the reference adult. This work investigates the impact of the use of these new computational phantoms. The absorbed doses were calculated for 11 different radiopharmaceuticals currently used in diagnostic nuclear medicine. They were calculated for the ICRP 110 reference computational phantoms using the OEDIPE software and the MCNP extended Monte Carlo code. The biokinetic models were issued from ICRP Publications 53, 80 and 106. The results were then compared with published values given in these ICRP Publications. To discriminate the effect of anatomical differences on organ doses from the effect of the calculation method, the Monte Carlo calculations were repeated for the reference adult stylised phantom. The voxel effect, the influence of the use of different densities and nuclear decay data were also investigated. Effective doses were determined for the ICRP 110 adult reference computational phantom with the tissue weighting factor of ICRP Publication 60 and the tissue weighting factors of ICRP Publication 103. The calculation method and, in particular, the simulation of the electron transport have a significant influence on the calculated doses, especially, for small and walled organs. Overestimates of >200 % were observed for the urinary bladder wall of the stylised phantom compared with the computational phantoms. The unrealistic organ topology of the stylised phantom leads to important dose differences, sometimes by an order of magnitude. The effective doses calculated using the new computational phantoms and the new tissue weighting factors are globally lower than the published ones, except for some

  18. The plenary session on the ICRP recommendations for the 21st century at IRPA-11, Madrid.

    PubMed

    Webb, Geoffrey A M; Magnússon, Sigurdur M; Lacoste, Andre-Claude; Tsela, Simanga Alex; Jones, C Rick; Fujimoto, Kenzo; Loy, John; Coates, Roger

    2004-12-01

    During the IRPA-11 Congress in Madrid in May 2004, a technical panel session was devoted to the presentation and discussion of the draft 2005 recommendations of the ICRP. Panel members had been given privileged access to the new draft and had been asked to concentrate on specific areas. This memorandum summarises the initial presentation of the main ideas in the draft recommendations by the ICRP Chairman, Roger Clarke, and then presents the views of the six panellists.

  19. Implications of recent ICRP recommendations for risk assessments for radioactive waste disposal and cleanup

    SciTech Connect

    Devgun, J.S.

    1992-01-01

    The International Commission on Radiological Protection (ICRP) adopted a new set of recommendations in November 1990 which were issued at ICRP Publication No. 60 in March 1991. These recommendations incorporate new radiobiological information and outline a comprehensive system of radiological protection. This paper evaluates the implications of these new recommendations vis a vis risk assessments for radioactive waste disposal and remediation of radioactively contaminated sites.

  20. Implications of recent ICRP recommendations for risk assessments for radioactive waste disposal and cleanup

    SciTech Connect

    Devgun, J.S.

    1992-04-01

    The International Commission on Radiological Protection (ICRP) adopted a new set of recommendations in November 1990 which were issued at ICRP Publication No. 60 in March 1991. These recommendations incorporate new radiobiological information and outline a comprehensive system of radiological protection. This paper evaluates the implications of these new recommendations vis a vis risk assessments for radioactive waste disposal and remediation of radioactively contaminated sites.

  1. Derivation of site-specific skeletal masses within the current ICRP age series.

    PubMed

    Watchman, Christopher J; Hasenauer, Deanna; Bolch, Wesley E

    2007-06-07

    The calculation of absorbed dose to the radiosensitive tissues of the skeleton is routinely performed using reference masses provided in publications from the International Commission on Radiological Protection (ICRP). These values typically include total skeleton tissue masses by reference subject age, but not by individual bone site at a given age. Site-specific variations in absorbed fractions are known to occur for internal alpha-particle and beta-particle emitters, and in certain medical dose reconstructions, site-specific estimates of marrow dose may be desirable. Furthermore, bone-site-specific tissue masses are required to properly estimate skeletal-averaged absorbed fractions and, more importantly, specific absorbed fractions for internalized radionuclides and radiopharmaceuticals. Reference masses by skeletal site are also needed in the development of ICRP compliant tomographic phantoms, as this organ system is initially segmented from medical images only as a homogeneous tissue region. ICRP reference skeletal masses are assigned based upon several independent data sources, many of which may not be entirely consistent with one another. In this study, a methodology is presented, using data from the various ICRP publications, to derive site-specific skeletal tissue masses for each member of the ICRP age series. Active marrow masses are calculated and differences are shown with respect to ICRP Publications 70 and 89 values. New data for a revised surrogate tissue region for the osteoprogenitor cells within bone marrow is presented with estimates of its total mass throughout the skeleton and for different subject ages.

  2. Connecting Critical Reflection and Group Development in Online Adult Education Classrooms

    ERIC Educational Resources Information Center

    Glowacki-Dudka, Michelle; Barnett, Nicole

    2007-01-01

    This qualitative multi-case study explored the space where critical reflection and group development met within the online environment for the adult learner. Using critical reflection with adult learners through their responses to Stephen Brookfield's (1995) Critical Incident Questionnaire (CIQ) in the online environment precipitated instructional…

  3. Renormalization Group for Critical Phenomena in Complex Networks

    PubMed Central

    Boettcher, S.; Brunson, C. T.

    2011-01-01

    We discuss the behavior of statistical models on a novel class of complex “Hanoi” networks. Such modeling is often the cornerstone for the understanding of many dynamical processes in complex networks. Hanoi networks are special because they integrate small-world hierarchies common to many social and economical structures with the inevitable geometry of the real world these structures exist in. In addition, their design allows exact results to be obtained with the venerable renormalization group (RG). Our treatment will provide a detailed, pedagogical introduction to RG. In particular, we will study the Ising model with RG, for which the fixed points are determined and the RG flow is analyzed. We show that the small-world bonds result in non-universal behavior. It is shown that a diversity of different behaviors can be observed with seemingly small changes in the structure of hierarchical networks generally, and we provide a general theory to describe our findings. PMID:22194725

  4. Path integrals, differential renormalization-group, and stochastic systems near criticality

    NASA Technical Reports Server (NTRS)

    Chang, Tom

    1992-01-01

    It is demonstrated, using the techniques of path integrals and renormalization-group, that nonlinear stochastic systems near criticality (including self-organized criticality) generally exhibit low-dimensional behavior. The symmetry which characterizes a particular criticality can be broken by the appearance of relevant scaling fields. A connection is made between the fractal dimensions of finite-dimensional chaotic systems and the anomalous dimensions in stochastic systems near criticality. The effect of additional random noise on stochastic systems is also delineated.

  5. What Could Critical Mathematics Education Mean for Different Groups of Students?

    ERIC Educational Resources Information Center

    Skovsmose, Ole

    2016-01-01

    In this article I consider what critical mathematics education could mean for different groups of students. Much discussion and research has addressed students at social risk. My point, however, is that critical mathematics education concerns other groups as well: for example, students in comfortable positions, blind students, elderly students,…

  6. What Could Critical Mathematics Education Mean for Different Groups of Students?

    ERIC Educational Resources Information Center

    Skovsmose, Ole

    2016-01-01

    In this article I consider what critical mathematics education could mean for different groups of students. Much discussion and research has addressed students at social risk. My point, however, is that critical mathematics education concerns other groups as well: for example, students in comfortable positions, blind students, elderly students,…

  7. Overview of ICRP Committee 3: protection in medicine.

    PubMed

    Vañó, E; Miller, D L; Rehani, M M

    2016-06-01

    Committee 3 of the International Commission on Radiological Protection (ICRP) develops recommendations and guidance for protection of patients, staff, and the public against radiation exposure when ionising radiation is used for medical diagnosis, therapy, or biomedical research. This paper presents a summary of the work that Committee 3 has accomplished over the past few years, and also describes its current work. The most recent reports published by the Commission that relate to radiological protection in medicine are 'Radiological protection in cone beam computed tomography' (Publication 129), 'Radiation dose to patients from radiopharmaceuticals: a compendium of current information related to frequently used substances' (Publication 128, in cooperation with Committee 2), 'Radiological protection in ion beam radiotherapy' (Publication 127), 'Radiological protection in paediatric diagnostic and interventional radiology' (Publication 121), 'Radiological protection in cardiology' (Publication 120), and 'Radiological protection in fluoroscopically guided procedures outside the imaging department' (Publication 117). A new report on diagnostic reference levels in medical imaging will provide specific advice for interventional radiology, digital imaging, computed tomography, nuclear medicine, paediatrics, and hybrid (multi-modality) imaging procedures, and is expected to be published in 2016. Committee 3 is also working on guidance for occupational radiological protection in brachytherapy, and on guidance on occupational protection issues in interventional procedures, paying particular attention to the 2011 Commission's recommendations on the occupational dose limit for the lens of the eye (Publication 118). Other reports in preparation deal with justification, radiological protection in therapy with radiopharmaceuticals, radiological protection in medicine as related to individual radiosusceptibility, appropriate use of effective dose (in cooperation with other

  8. Impact of the new nuclear decay data of ICRP publication 107 on inhalation dose coefficients for workers.

    PubMed

    Manabe, K; Endo, A; Eckerman, K F

    2010-03-01

    The impact a revision of nuclear decay data had on dose coefficients was studied using data newly published in ICRP Publication 107 (ICRP 107) and existing data from ICRP Publication 38 (ICRP 38). Committed effective dose coefficients for occupational inhalation of radionuclides were calculated using two sets of decay data with the dose and risk calculation software DCAL for 90 elements, 774 nuclides and 1572 cases. The dose coefficients based on ICRP 107 increased by over 10 % compared with those based on ICRP 38 in 98 cases, and decreased by over 10 % in 54 cases. It was found that the differences in dose coefficients mainly originated from changes in the radiation energy emitted per nuclear transformation. In addition, revisions of the half-lives, radiation types and decay modes also resulted in changes in the dose coefficients.

  9. Use of the ICRP system for the protection of marine ecosystems.

    PubMed

    Telleria, D; Cabianca, T; Proehl, G; Kliaus, V; Brown, J; Bossio, C; Van der Wolf, J; Bonchuk, I; Nilsen, M

    2015-06-01

    The International Commission on Radiological Protection (ICRP) recently reinforced the international system of radiological protection, initially focused on humans, by identifying principles of environmental protection and proposing a framework for assessing impacts of ionising radiation on non-human species, based on a reference flora and fauna approach. For this purpose, ICRP developed dosimetric models for a set of Reference Animals and Plants, which are representative of flora and fauna in different environments (terrestrial, freshwater, marine), and produced criteria based on information on radiation effects, with the aim of evaluating the level of potential or actual radiological impacts, and as an input for decision making. The approach developed by ICRP for flora and fauna is consistent with the approach used to protect humans. The International Atomic Energy Agency (IAEA) includes considerations on the protection of the environment in its safety standards, and is currently developing guidelines to assess radiological impacts based on the aforementioned ICRP approach. This paper presents the method developed by IAEA, in a series of meetings with international experts, to enable assessment of the radiological impact to the marine environment in connection with the Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter 1972 (London Convention 1972). This method is based on IAEA's safety standards and ICRP's recommendations, and was presented in 2013 for consideration by representatives of the contracting parties of the London Convention 1972; it was approved for inclusion in its procedures, and is in the process of being incorporated into guidelines.

  10. Statistics of Statisticians: Critical Mass of Statistics and Operational Research Groups

    NASA Astrophysics Data System (ADS)

    Kenna, Ralph; Berche, Bertrand

    Using a recently developed model, inspired by mean field theory in statistical physics, and data from the UK's Research Assessment Exercise, we analyse the relationship between the qualities of statistics and operational research groups and the quantities of researchers in them. Similar to other academic disciplines, we provide evidence for a linear dependency of quality on quantity up to an upper critical mass, which is interpreted as the average maximum number of colleagues with whom a researcher can communicate meaningfully within a research group. The model also predicts a lower critical mass, which research groups should strive to achieve to avoid extinction. For statistics and operational research, the lower critical mass is estimated to be 9 ± 3. The upper critical mass, beyond which research quality does not significantly depend on group size, is 17 ± 6.

  11. Radiological Protection Issues Arising During and After the Fukushima Nuclear Reactor Accident-Memorandum of TG 84 of ICRP.

    PubMed

    Weiss, Wolfgang

    2016-09-01

    Observations and lessons identified after the Fukushima accident have been collected and assessed by ICRP Task Group 84. Together with the observations of other expert organizations, they are being used to further develop the current system of protection. While many of the established protection criteria remain valid, improvements are needed in three areas. Key issues related to the need of planning for long-term protective actions (criteria for returning home, dealing with waste) have to be implemented as important elements of the national protection strategies during the preparedness stage. The justification of disruptive protective actions and the protection of vulnerably groups of the population need to be reconsidered to avoid unpleasant imbalances and outcomes. The coexistence of radiation-induced health effects and health effects with social determinants requires consideration of both aspects in decision-making and response.

  12. Exploring creativity and critical thinking in traditional and innovative problem-based learning groups.

    PubMed

    Chan, Zenobia C Y

    2013-08-01

    To explore students' attitude towards problem-based learning, creativity and critical thinking, and the relevance to nursing education and clinical practice. Critical thinking and creativity are crucial in nursing education. The teaching approach of problem-based learning can help to reduce the difficulties of nurturing problem-solving skills. However, there is little in the literature on how to improve the effectiveness of a problem-based learning lesson by designing appropriate and innovative activities such as composing songs, writing poems and using role plays. Exploratory qualitative study. A sample of 100 students participated in seven semi-structured focus groups, of which two were innovative groups and five were standard groups, adopting three activities in problem-based learning, namely composing songs, writing poems and performing role plays. The data were analysed using thematic analysis. There are three themes extracted from the conversations: 'students' perceptions of problem-based learning', 'students' perceptions of creative thinking' and 'students' perceptions of critical thinking'. Participants generally agreed that critical thinking is more important than creativity in problem-based learning and clinical practice. Participants in the innovative groups perceived a significantly closer relationship between critical thinking and nursing care, and between creativity and nursing care than the standard groups. Both standard and innovative groups agreed that problem-based learning could significantly increase their critical thinking and problem-solving skills. Further, by composing songs, writing poems and using role plays, the innovative groups had significantly increased their awareness of the relationship among critical thinking, creativity and nursing care. Nursing educators should include more types of creative activities than it often does in conventional problem-based learning classes. The results could help nurse educators design an appropriate

  13. Group Work and the Learning of Critical Thinking in the Hong Kong Secondary Liberal Studies Curriculum

    ERIC Educational Resources Information Center

    Fung, Dennis; Howe, Christine

    2014-01-01

    This article reports the findings of a one-year longitudinal study that investigated the impact of group work on the development of students' critical thinking in Hong Kong secondary schools. It explores whether the participation of teachers in a group-based teaching intervention adapted from an earlier study conducted in the United Kingdom (UK)…

  14. Group process research and emergence of therapeutic factors in critical incident stress debriefing.

    PubMed

    Pender, Debra A; Prichard, Karen K

    2008-01-01

    Critical incident stress debriefing is a highly utilized and often debated form of post-trauma exposure intervention. This article presents exploratory group process research that utilized a mixed method approach and group process research techniques. The article's findings, the emergence of therapeutic factors, support that CISD group work does yield indicators consistent with support/ psychoeducation groups with a crisis theme. Further the events that trigger the intervention yield specific therapeutic factors. CISD group work may be better understood through established group research patterns.

  15. Density functional theory integrated with renormalization group theory for criticality of nanoconfined fluids.

    PubMed

    Zeng, Ming; Mi, Jianguo; Zhong, Chongli

    2010-03-25

    Nanoconfined fluids exhibit complicated behavior such as phase transitions, prewetting, wetting transitions, universal critical properties, and critical point shifts, attributed to the cooperative interactions of short- and long-range density fluctuations. In this work, a theoretical approach, an integrated density functional (DF) and renormalization group (RG) theory, is developed to investigate the critical properties of fluids confined in slit pores or bounded by single wall surfaces. The approach can take into account both the local and the long-range density fluctuations of confined fluids self-consistently. The predicted critical order parameter exponent beta is about 1/8, and the wetting exponent beta(s) is 1.056 +/- 0.011. These values are quite close to the two-dimensional Ising values, demonstrating that the new theoretical approach is reliable as a description of criticality in nanoconfined fluids. Correspondingly, the global phase transitions and surface wetting transitions are analyzed.

  16. The postnatal growth of ICRP target organs in reference humans: Spleen and liver

    SciTech Connect

    Walker, J.T. )

    1989-12-01

    Attempts to improve radiation dose estimates to infants and children are hampered because of the lack of mathematical models that describe the age variation in anatomical and physiological parameters. Specifically, for one anatomical parameter, organ size, there are no growth models available to the health physics community. In this paper, an empirical mathematical model is introduced for estimating age-specific masses of two ICRP target organs: the spleen and liver. That model, the Power Logistic Additive (PLA) growth model, is fitted to ICRP 23 organ growth data to determine five growth parameters. This model assumes that organs grow under the influence of two main processes: a primary (power function) and a sexual maturation (logistic function) process, which are additive from birth to adulthood. The results show that the model describes the ICRP growth data quite well. Growth parameters and tables listing the predicted masses and mass velocities as a function of age for each organ are provided for application in the ICRP modeling system.

  17. Comparison of mean quality factors proposed by ICRP, ICRU and NASA

    NASA Astrophysics Data System (ADS)

    Sato, Tatsuhiko; Niita, Koji; Endo, Akira

    2012-07-01

    Astronauts are exposed to primary cosmic-rays and secondary particles produced by them through interaction with the atoms of the spacecraft material and those of the human body. For the radiation risk estimation of astronauts, not only organ absorbed doses but also their mean quality factors must be evaluated, since radiation weighting factor as defined by ICRP60 is not suitable for use in space dosimetry due to its very simplified concept. Three relationships were proposed for expressing the radiation quality by different organizations; (1) International Commission on Radiological Protection (ICRP) defined the quality factor based on LET in water, Q(L), in ICRP60, (2) in International Commission on Radiation Units and Measurements (ICRU) Report 40, a quality factor Q(y) is defined as a function of lineal energy, y, for spherical liquid water of 1 mm in diameter, Q(y), and (3) National Aeronautics and Space Administration (NASA) proposed those for solid cancer and leukemia separately based on charge and energy of particles, QNASA(Z,E), in NASA/TP-2011-216155. The Q(L) relationship is most simple and widely used in space dosimetry, but the latter two relationships consider the difference of the track structure of the various heavy ions in tissue due to the production of d-rays, which is very important in the risk estimation for the HZE-particle exposure. We therefore calculated the mean quality factors in organs and tissues in the ICRP reference voxel phantoms for various particles, using the PHITS code coupled with the ICRP, ICRU and NASA Q-functions. An isotropic irradiation of the phantom was assumed in the calculation. The details of the calculation procedure will be described, together with the comparison of mean quality factors obtained from the 3 relationships.

  18. CT effective dose per dose length product using ICRP 103 weighting factors

    SciTech Connect

    Huda, Walter; Magill, Dennise; He Wenjun

    2011-03-15

    Purpose: To generate effective dose per unit dose length product (E/DLP) conversion factors incorporating ICRP Publication 103 tissue weighting factors. Methods: Effective doses for CT examinations were obtained using the IMPACT Dosimetry Calculator using all 23 dose data sets that are offered by this spreadsheet. CT examinations were simulated for scans performed along the patient long axis for each dosimetry data set using a 4 cm beam width ranging from the upper thighs to top of the head. Five basic body regions (head, neck, chest, abdomen, and pelvis), as well as combinations of the regions (head/neck, chest/abdomen, abdomen/pelvis, and chest/abdomen/pelvis) and whole body CT scans were investigated. Correction factors were generated that can be applied to convert E/DLP conversion factors based on ICRP 60 data to conversion factors that are valid for ICRP 103 data (i.e., E{sub 103}/E{sub 60}). Results: Use of ICRP 103 weighting factors increase effective doses for head scans by {approx}11%, for chest scans by {approx}20%, and decrease effective doses for pelvis scans by {approx}25%. Current E/DLP conversion factors are estimated to be 2.4 {mu}Sv/mGy cm for head CT examinations and range between 14 and 20 {mu}Sv/mGy cm for body CT examinations. Conclusions: Factors that enable patient CT doses to be adjusted to account for ICRP 103 tissue weighting factors are provided, which result in E/DLP factors that were increased in head and chest CT, reduced in pelvis CT, and showed no marked change in neck and abdomen CT.

  19. S values for 131I based on the ICRP adult voxel phantoms

    PubMed Central

    Lamart, Stephanie; Simon, Steven L.; Bouville, Andre; Moroz, Brian E.; Lee, Choonsik

    2016-01-01

    To improve the estimates of organ doses from nuclear medicine procedures using 131I, the authors calculated a comprehensive set of 131I S values, defined as absorbed doses in target tissues per unit of nuclear transition in source regions, for different source and target combinations. The authors used the latest reference adult male and female voxel phantoms published by the International Commission on Radiological Protection (ICRP Publication 110) and the 131I photon and electron spectra from the ICRP Publication 107 to perform Monte Carlo radiation transport calculations using MCNPX2.7 to compute the S values. For each phantom, the authors simulated 55 source regions with an assumed uniform distribution of 131I. They computed the S values for 42 target tissues directly, without calculating specific absorbed fractions. From these calculations, the authors derived a comprehensive set of S values for 131I for 55 source regions and 42 target tissues in the ICRP male and female voxel phantoms. Compared with the stylised phantoms from Oak Ridge National Laboratory (ORNL) that consist of 22 source regions and 24 target regions, the new data set includes 1662 additional S values corresponding to additional combinations of source–target tissues that are not available in the stylised phantoms. In a comparison of S values derived from the ICRP and ORNL phantoms, the authors found that the S values to the radiosensitive tissues in the ICRP phantoms were 1.1 (median, female) and 1.3 (median, male) times greater than the values based on the ORNL phantoms. However, for several source–target pairs, the difference was up to 10-fold. The new set of S values can be applied prospectively or retrospectively to the calculation of radiation doses in adults internally exposed to 131I, including nuclear medicine patients treated for thyroid cancer or hyperthyroidism. PMID:25829162

  20. S values for 131I based on the ICRP adult voxel phantoms.

    PubMed

    Lamart, Stephanie; Simon, Steven L; Bouville, Andre; Moroz, Brian E; Lee, Choonsik

    2016-01-01

    To improve the estimates of organ doses from nuclear medicine procedures using (131)I, the authors calculated a comprehensive set of (131)I S values, defined as absorbed doses in target tissues per unit of nuclear transition in source regions, for different source and target combinations. The authors used the latest reference adult male and female voxel phantoms published by the International Commission on Radiological Protection (ICRP Publication 110) and the (131)I photon and electron spectra from the ICRP Publication 107 to perform Monte Carlo radiation transport calculations using MCNPX2.7 to compute the S values. For each phantom, the authors simulated 55 source regions with an assumed uniform distribution of (131)I. They computed the S values for 42 target tissues directly, without calculating specific absorbed fractions. From these calculations, the authors derived a comprehensive set of S values for (131)I for 55 source regions and 42 target tissues in the ICRP male and female voxel phantoms. Compared with the stylised phantoms from Oak Ridge National Laboratory (ORNL) that consist of 22 source regions and 24 target regions, the new data set includes 1662 additional S values corresponding to additional combinations of source-target tissues that are not available in the stylised phantoms. In a comparison of S values derived from the ICRP and ORNL phantoms, the authors found that the S values to the radiosensitive tissues in the ICRP phantoms were 1.1 (median, female) and 1.3 (median, male) times greater than the values based on the ORNL phantoms. However, for several source-target pairs, the difference was up to 10-fold. The new set of S values can be applied prospectively or retrospectively to the calculation of radiation doses in adults internally exposed to (131)I, including nuclear medicine patients treated for thyroid cancer or hyperthyroidism.

  1. A critical review of labor and birth care. Obstetrical Interest Group of the North American Primary Care Research Group.

    PubMed

    Smith, M A; Acheson, L S; Byrd, J E; Curtis, P; Day, T W; Frank, S H; Franks, P; Graham, A V; LeFevre, M; Resnick, J

    1991-09-01

    A critical review of the literature regarding important aspects of labor and delivery was conducted by members of the Obstetrical Interest Group of the North American Primary Care Research Group using computerized searches, personal communication, and literature exchange between group members. Each written topic summary was carefully reviewed by a second group member, and a consensus was reached regarding conclusions and recommendations by the group. The topics include family involvement, comfort measures, fetal heart rate monitoring, labor augmentation, birth positions, and episiotomies. Each topic summary is preceded by conclusions and recommendations given in the order of least invasive to most invasive of the woman in labor. The strength of these conclusions and recommendations is based on the amount and type of supportive data in the literature and is indicated by one to three stars preceding that statement. One-star conclusions are not well supported in the literature but reflect a family practice style and were reached through consensus from the group. Three-star conclusions are supported by data from clinical trials.

  2. Review of the ICRP tritium and 14C internal dosimetry models and their implementation in the Genmod-PC code.

    PubMed

    Richardson, R B; Dunford, D W

    2001-09-01

    Biokinetic models for tritium and 14C compounds, as described by various ICRP publications, have been incorporated into the Genmod-PC internal dosimetry code. This work reviews the models for tritium and 14C labeled compounds that the ICRP has formulated over several decades. The ICRP dosimetry prescribed for hydrogen and carbon radionuclides is fundamentally different from that recommended for other elements in that it is based on retention functions for whole body activity instead of compartmental biokinetic models. The ICRP recommends dosimetric methods for tritium and 14C compounds, ten of which are coded in Genmod-PC as compartmental models, namely, five tritium compounds, e.g., tritiated water, tritium gas, and five 14C compounds, e.g., carbon dioxide, carbon-labeled methane. The values of the Genmod-PC calculated dose coefficients were compared with the ICRP's values. It is shown how the dose coefficients for intakes of tritium and 14C compounds are affected by different interpretations of the methods recommended by the ICRP for two of the three classes of vapors and gases. Some aspects of the ICRP models, such as the percent oxidized, would benefit from reconsideration so as to produce tritium and 14C biokinetics that are less dependent on the radionuclide.

  3. ICRP Publication 114. Environmental protection: transfer parameters for reference animals and plants.

    PubMed

    Strand, P; Beresford, N; Copplestone, D; Godoy, J; Jianguo, L; Saxén, R; Yankovich, T; Brown, J

    2009-12-01

    In Publication 103 (ICRP, 2007), the Commission included a section on the protection of the environment, and indicated that it would be further developing its approach to this difficult subject by way of a set of Reference Animals and Plants (RAPs) as the basis for relating exposure to dose, and dose to radiation effects, for different types of animals and plants. Subsequently, a set of 12 RAPs has been described in some detail (ICRP, 2008), particularly with regard to estimation of the doses received by them, at a whole-body level, in relation to internal and external radionuclide concentrations; and what is known about the effects of radiation on such types of animals and plants. A set of dose conversion factors for all of the RAPs has been derived, and the resultant dose rates can be compared with evaluations of the effects of dose rates using derived consideration reference levels (DCRLs). Each DCRL constitutes a band of dose rates for each RAP within which there is likely to be some chance of the occurrence of deleterious effects. Site-specific data on Representative Organisms (i.e. organisms of specific interest for an assessment) can then be compared with such values and used as a basis for decision making. It is intended that the Commission's approach to protection of the environment be applied to all exposure situations. In some situations, the relevant radionuclide concentrations can be measured directly, but this is not always possible or feasible. In such cases, modelling techniques are used to estimate the radionuclide concentrations. This report is an initial step in addressing the needs of such modelling techniques. After briefly reviewing the basic factors relating to the accumulation of radionuclides by different types of biota, in different habitats, and at different stages in the life cycle, this report focuses on the approaches used to model the transfer of radionuclides through the environment. It concludes that equilibrium concentration ratios

  4. Variations on a Theme: As Needs Change, New Models of Critical Friends Groups Emerge

    ERIC Educational Resources Information Center

    Fahey, Kevin; Ippolito, Jacy

    2015-01-01

    The Critical Friends Group, a highly articulated model of professional learning, posits that, in order for teachers to learn together in ways that change their practice, the content and nature of their conversations must change (National School Reform Faculty, 2012). The content needs to change from externally driven agendas that address (in a…

  5. Group Communication and Critical Thinking Competence Development Using a Reality-Based Project

    ERIC Educational Resources Information Center

    Paulson, Edward

    2011-01-01

    The presented merger and acquisition classroom exercise is based on a real yet incomplete transaction transpiring during the period of the class. The approach enables adult students to apply their previously acquired business experience to a strategic analysis project facilitating the development of group communication, critical thinking, and…

  6. Maintaining, Reframing, and Disrupting Traditional Expectations and Outcomes for Professional Development with Critical Friends Groups

    ERIC Educational Resources Information Center

    Burke, Wendy; Marx, Gary E.; Berry, James E.

    2011-01-01

    Districts across the country are currently adopting models of professional learning communities (PLCs) as a means for improving teachers' instructional practice and student achievement. This evaluation research case study shares the 3-year history, development, and challenges of a district-wide implementation of Critical Friends Groups (CFGs), a…

  7. Group Communication and Critical Thinking Competence Development Using a Reality-Based Project

    ERIC Educational Resources Information Center

    Paulson, Edward

    2011-01-01

    The presented merger and acquisition classroom exercise is based on a real yet incomplete transaction transpiring during the period of the class. The approach enables adult students to apply their previously acquired business experience to a strategic analysis project facilitating the development of group communication, critical thinking, and…

  8. Critical Classrooms: Using Artists' Lives to Teach Young Students Social Groups, Power, and Privilege

    ERIC Educational Resources Information Center

    Silva, Janelle M.

    2012-01-01

    This article uses data from a 9-month ethnography in California to illustrate how elementary teacher's decision to reenact Jane Elliott's "A Class Divided" experiment, in conjunction with an artist-centered multicultural curriculum, shifted classroom conversations to a more critical dialogue of social groups, power, and privilege. Data…

  9. Critical Classrooms: Using Artists' Lives to Teach Young Students Social Groups, Power, and Privilege

    ERIC Educational Resources Information Center

    Silva, Janelle M.

    2012-01-01

    This article uses data from a 9-month ethnography in California to illustrate how elementary teacher's decision to reenact Jane Elliott's "A Class Divided" experiment, in conjunction with an artist-centered multicultural curriculum, shifted classroom conversations to a more critical dialogue of social groups, power, and privilege. Data…

  10. Liberal Studies in Hong Kong: A New Perspective on Critical Thinking through Group Work

    ERIC Educational Resources Information Center

    Fung, Dennis; Howe, Christine

    2012-01-01

    This article reports research that is contextualised within reforms of secondary education in Hong Kong and the reintroduction of Liberal Studies, which jointly emphasise the need for a learning environment that facilitates the practice of group work and the development of critical thinking. A study is described that explores the relevance of…

  11. Spinal-cord stimulation in critical limb ischaemia: a randomised trial. ESES Study Group.

    PubMed

    Klomp, H M; Spincemaille, G H; Steyerberg, E W; Habbema, J D; van Urk, H

    1999-03-27

    For patients with critical limb ischaemia, spinal-cord stimulation has been advocated for the treatment of ischaemic pain and the prevention of amputation. We compared the efficacy of the addition of spinal-cord stimulation to best medical treatment in a randomised controlled trial. 120 patients with critical limb ischaemia not suitable for vascular reconstruction were randomly assigned either spinal-cord stimulation in addition to best medical treatment or best medical treatment alone. Primary outcomes were mortality and amputation. The primary endpoint was limb survival at 2 years. The mean (SD) age of the patients was 72.6 years (10.3). Median (IQR) follow-up was 605 days (244-1171). 40 (67%) of 60 patients in the spinal-cord-stimulator group and 41 (68%) of 60 patients in the standard group were alive at the end of the study, (p=0.96). There were 25 major amputations in the spinal-cord-stimulator group and 29 in the standard group, (p=0.47). The hazard ratio for survival at 2 years without major amputation in the spinal-cord stimulation group compared with the standard group was 0.96 (95% CI 0.61-1.51). Spinal-cord-stimulation in addition to best medical care does not prevent amputation in patients with critical limb ischaemia.

  12. Universal critical behavior of noisy coupled oscillators: a renormalization group study.

    PubMed

    Risler, Thomas; Prost, Jacques; Jülicher, Frank

    2005-07-01

    We show that the synchronization transition of a large number of noisy coupled oscillators is an example for a dynamic critical point far from thermodynamic equilibrium. The universal behaviors of such critical oscillators, arranged on a lattice in a d -dimensional space and coupled by nearest-neighbors interactions, can be studied using field-theoretical methods. The field theory associated with the critical point of a homogeneous oscillatory instability (or Hopf bifurcation of coupled oscillators) is the complex Ginzburg-Landau equation with additive noise. We perform a perturbative renormalization group (RG) study in a (4-epsilon)-dimensional space. We develop an RG scheme that eliminates the phase and frequency of the oscillations using a scale-dependent oscillating reference frame. Within Callan-Symanzik's RG scheme to two-loop order in perturbation theory, we find that the RG fixed point is formally related to the one of the model A dynamics of the real Ginzburg-Landau theory with an O2 symmetry of the order parameter. Therefore, the dominant critical exponents for coupled oscillators are the same as for this equilibrium field theory. This formal connection with an equilibrium critical point imposes a relation between the correlation and response functions of coupled oscillators in the critical regime. Since the system operates far from thermodynamic equilibrium, a strong violation of the fluctuation-dissipation relation occurs and is characterized by a universal divergence of an effective temperature. The formal relation between critical oscillators and equilibrium critical points suggests that long-range phase order exists in critical oscillators above two dimensions.

  13. ICRP PUBLICATION 122: radiological protection in geological disposal of long-lived solid radioactive waste.

    PubMed

    Weiss, W; Larsson, C-M; McKenney, C; Minon, J-P; Mobbs, S; Schneider, T; Umeki, H; Hilden, W; Pescatore, C; Vesterlind, M

    2013-06-01

    This report updates and consolidates previous recommendations of the International Commission on Radiological Protection (ICRP) related to solid waste disposal (ICRP, 1985, 1997b, 1998). The recommendations given apply specifically to geological disposal of long-lived solid radioactive waste. The report explains how the ICRP system of radiological protection described in Publication 103 (ICRP, 2007) can be applied in the context of the geological disposal of long-lived solid radioactive waste. Although the report is written as a standalone document, previous ICRP recommendations not dealt with in depth in the report are still valid. The 2007 ICRP system of radiological protection evolves from the previous process-based protection approach relying on the distinction between practices and interventions by moving to an approach based on the distinction between three types of exposure situation: planned, emergency and existing. The Recommendations maintains the Commission's three fundamental principles of radiological protection namely: justification, optimisation of protection and the application of dose limits. They also maintain the current individual dose limits for effective dose and equivalent dose from all regulated sources in planned exposure situations. They re-enforce the principle of optimisation of radiological protection, which applies in a similar way to all exposure situations, subject to restrictions on individual doses: constraints for planned exposure situations, and reference levels for emergency and existing exposure situations. The Recommendations also include an approach for developing a framework to demonstrate radiological protection of the environment. This report describes the different stages in the life time of a geological disposal facility, and addresses the application of relevant radiological protection principles for each stage depending on the various exposure situations that can be encountered. In particular, the crucial factor that

  14. Application of the renormalization group to critical phenomena in magnetic systems

    NASA Astrophysics Data System (ADS)

    Fujki, Nahomi M.

    1989-07-01

    Applications of renormalization group methods to the study of critical phenomena in magnetic systems are discussed. A real space renormalization group method is applied to short range interaction systems. A systematic development of the method by high temperature series expansions is given and tested on square and triangular lattices. A weight function appropriate to a graphical description is introduced. Field-theoretic renormalization group methods for dipolar magnetic systems show that uniaxial dipolar systems have unusual critical properties including an upper critical dimension of d(sub c)=3. An efficient method of dipolar summation is presented and applied to several lattice systems. In particular, it is shown that the dipolar interaction can cause uniaxial spin anisotropy in hexagonal close-packed gadolinium. Crossover effects in gadolinium are discussed and reduced crossover temperatures are obtained. Motivated by the role of the spin-spin pair correlation function for scattering cross-sections and the resistivity of gadolinium, the correction to scaling behavior of the pair correlation function for systems at the upper critical dimension is studied using renormalized perturbation theory and the operator product expansion.

  15. Protocols and Hospital Mortality in Critically Ill Patients: The United States Critical Illness and Injury Trials Group Critical Illness Outcomes Study.

    PubMed

    Sevransky, Jonathan E; Checkley, William; Herrera, Phabiola; Pickering, Brian W; Barr, Juliana; Brown, Samuel M; Chang, Steven Y; Chong, David; Kaufman, David; Fremont, Richard D; Girard, Timothy D; Hoag, Jeffrey; Johnson, Steven B; Kerlin, Mehta P; Liebler, Janice; O'Brien, James; O'Keefe, Terence; Park, Pauline K; Pastores, Stephen M; Patil, Namrata; Pietropaoli, Anthony P; Putman, Maryann; Rice, Todd W; Rotello, Leo; Siner, Jonathan; Sajid, Sahul; Murphy, David J; Martin, Greg S

    2015-10-01

    Clinical protocols may decrease unnecessary variation in care and improve compliance with desirable therapies. We evaluated whether highly protocolized ICUs have superior patient outcomes compared with less highly protocolized ICUs. Observational study in which participating ICUs completed a general assessment and enrolled new patients 1 day each week. A total of 6,179 critically ill patients. Fifty-nine ICUs in the United States Critical Illness and Injury Trials Group Critical Illness Outcomes Study. None. The primary exposure was the number of ICU protocols; the primary outcome was hospital mortality. A total of 5,809 participants were followed prospectively, and 5,454 patients in 57 ICUs had complete outcome data. The median number of protocols per ICU was 19 (interquartile range, 15-21.5). In single-variable analyses, there were no differences in ICU and hospital mortality, length of stay, use of mechanical ventilation, vasopressors, or continuous sedation among individuals in ICUs with a high versus low number of protocols. The lack of association was confirmed in adjusted multivariable analysis (p = 0.70). Protocol compliance with two ventilator management protocols was moderate and did not differ between ICUs with high versus low numbers of protocols for lung protective ventilation in acute respiratory distress syndrome (47% vs 52%; p = 0.28) and for spontaneous breathing trials (55% vs 51%; p = 0.27). Clinical protocols are highly prevalent in U.S. ICUs. The presence of a greater number of protocols was not associated with protocol compliance or patient mortality.

  16. Influence of organs in the ICRP's remainder on effective dose equivalent computed for diagnostic radiation exposures

    SciTech Connect

    Gibbs, S.J.

    1989-04-01

    The ICRP effective dose equivalent has been compared with a weighted dose equivalent, computed by treating the entire remainder instead of the sample of five remainder organs in the ICRP method as uniformly radiosensitive, for dose distributions from three common diagnostic exposures: chest, dental full-mouth and dental panoramic. Complete dose distributions were computed by a Monte Carlo model. In all three cases the effective dose equivalent was greater than the weighted dose equivalent. The difference was only 20% for the chest exam but was more than fivefold for both dental exposures. Dose distributions for the dental exposures were less homogeneous than for the chest examination. Selection of organs to be included in the remainder markedly affects the effective dose equivalent. In the case of highly inhomogeneous dose distributions, the effective dose equivalent probably significantly over-estimates radiation detriment.

  17. Differential renormalization-group generators for static and dynamic critical phenomena

    NASA Astrophysics Data System (ADS)

    Chang, T. S.; Vvedensky, D. D.; Nicoll, J. F.

    1992-09-01

    The derivation of differential renormalization-group (DRG) equations for applications to static and dynamic critical phenomena is reviewed. The DRG approach provides a self-contained closed-form representation of the Wilson renormalization group (RG) and should be viewed as complementary to the Callan-Symanzik equations used in field-theoretic approaches to the RG. The various forms of DRG equations are derived to illustrate the general mathematical structure of each approach and to point out the advantages and disadvantages for performing practical calculations. Otherwise, the review focuses upon the one-particle-irreducible DRG equations derived by Nicoll and Chang and by Chang, Nicoll, and Young; no attempt is made to provide a general treatise of critical phenomena. A few specific examples are included to illustrate the utility of the DRG approach: the large- n limit of the classical n-vector model (the spherical model), multi- or higher-order critical phenomena, and crit ical dynamics far from equilibrium. The large- n limit of the n-vector model is used to introduce the application of DRG equations to a well-known example, with exact solution obtained for the nonlinear trajectories, generating functions for nonlinear scaling fields, and the equation of state. Trajectory integrals and nonlinear scaling fields within the framework of ɛ-expansions are then discussed for tricritical crossover, and briefly for certain aspects of multi- or higher-order critical points, including the derivation of the Helmholtz free energy and the equation of state. The discussion then turns to critical dynamics with a development of the path integral formulation for general dynamic processes. This is followed by an application to a model far-from-equilibrium system that undergoes a phase transformation analogous to a second-order critical point, the Schlögl model for a chemical instability.

  18. Validation of Nuclear Criticality Safety Software and 27 energy group ENDF/B-IV cross sections

    SciTech Connect

    Lee, B.L. Jr.

    1994-08-01

    The validation documented in this report is based on calculations that were executed during June through August 1992, and was completed in June 1993. The statistical analyses in Appendix C and Appendix D were completed in October 1993. This validation gives Portsmouth NCS personnel a basis for performing computerized KENO V.a calculations using the Martin Marietta Nuclear Criticality Safety Software. The first portion of the document outlines basic information in regard to validation of NCSS using ENDF/B-IV 27-group cross sections on the IBM 3090 at ORNL. A basic discussion of the NCSS system is provided, some discussion on the validation database and validation in general. Then follows a detailed description of the statistical analysis which was applied. The results of this validation indicate that the NCSS software may be used with confidence for criticality calculations at the Portsmouth Gaseous Diffusion Plant. When the validation results are treated as a single group, there is 95% confidence that 99.9% of future calculations of similar critical systems will have a calculated K{sub eff} > 0.9616. Based on this result the Portsmouth Nuclear Criticality Safety Department has adopted the calculational acceptance criteria that a k{sub eff} + 2{sigma} {le} 0.95 is safety subcritical. The validation of NCSS on the IBM 3090 at ORNL was extended to include NCSS on the IBM 3090 at K-25.

  19. Natural orbitals renormalization group approach to the two-impurity Kondo critical point

    NASA Astrophysics Data System (ADS)

    He, Rong-Qiang; Dai, Jianhui; Lu, Zhong-Yi

    2015-04-01

    The problem of two magnetic impurities in a normal metal exposes the two opposite tendencies in the formation of a singlet ground state, driven respectively by the single-ion Kondo effect with conduction electrons to screen impurity spins or the Ruderman-Kittel-Kasuya-Yosida interaction between the two impurities to directly form impurity spin singlet. However, whether the competition between these two tendencies can lead to a quantum critical point has been debated over more than two decades. Here, we study this problem by applying the newly proposed natural orbitals renormalization group method to a lattice version of the two-impurity Kondo model with a direct exchange K between the two impurity spins. The method allows for unbiased access to the ground state wave functions and low-lying excitations for sufficiently large system sizes. We demonstrate the existence of a quantum critical point, characterized by the power-law divergence of impurity staggered susceptibility with critical exponent γ =0.60 (1 ) , on the antiferromagnetic side of K when the interimpurity distance R is even lattice spacing, while a crossover behavior is recovered when R is odd lattice spacing. These results have ultimately resolved the long-standing discrepancy between the numerical renormalization group and quantum Monte Carlo studies, confirming a link of this two-impurity Kondo critical point to a hidden particle-hole symmetry predicted by the local Fermi liquid theory.

  20. Electron specific absorbed fractions for the adult male and female ICRP/ICRU reference computational phantoms

    NASA Astrophysics Data System (ADS)

    Zankl, Maria; Schlattl, Helmut; Petoussi-Henss, Nina; Hoeschen, Christoph

    2012-07-01

    The calculation of radiation dose from internally incorporated radionuclides is based on so-called absorbed fractions (AFs) and specific absorbed fractions (SAFs). SAFs for monoenergetic electrons were calculated for 63 source regions and 67 target regions using the new male and female adult reference computational phantoms adopted by the ICRP and ICRU and the Monte Carlo radiation transport programme package EGSnrc. The SAF values for electrons are opposed to the simplifying assumptions of ICRP Publication 30. The previously applied assumption of electrons being fully absorbed in the source organ itself is not always true at electron energies above approximately 300-500 keV. High-energy electrons have the ability to leave the source organ and, consequently, the electron SAFs for neighbouring organs can reach the same magnitude as those for photons for electron energies above 1 MeV. The reciprocity principle known for photons can be extended to electron SAFs as well, thus making cross-fire electron SAFs mass-independent. To quantify the impact of the improved electron dosimetry in comparison to the dosimetry using the simple assumptions of ICRP Publication 30, absorbed doses per administered activity of three radiopharmaceuticals were evaluated with and without explicit electron transport. The organ absorbed doses per administered activity for the two evaluation methods agree within 2%-3% for most organs for radionuclides with decay spectra having electron energies below a few hundred keV and within approximately 20% if higher electron energies are involved. An important exception is the urinary bladder wall, where the dose is overestimated by 60-150% using the simplified ICRP 30 approach for the radiopharmaceuticals of this study.

  1. Effective quality factors for neutrons based on the revised ICRP/ICRU recommendations.

    PubMed

    Veinot, K G; Hertel, N E

    2005-01-01

    The quality factor (Q) is intended to relate the biological effectiveness of a radiation to the absorbed dose delivered in tissue. Quality factors are defined as a function of the unrestricted linear energy transfer (L) relationship in water and are used with operational quantities. Radiation weighting factors (wR) are used in protection quantities to take into account total radiation detriment. While the International Commission on Radiological Protection (ICRP) defines the Q(L) relationship, the International Commission on Radiation Units and Measurements (ICRU) recommends the charged particle stopping power and range data. If either of these data recommendations change, the quality factors must be recomputed. The latest guidance from both organisations applicable to neutron quality factors are the ICRP Publication 60 (Q(L) relationship) and the ICRU Report 49 (stopping power and range data). In the present study, absorbed dose conversion coefficients (pGy cm2) were calculated for two operational quantities defined by the ICRU--the ambient absorbed dose and the personal absorbed dose. Dose-equivalent (pSv cm2) conversion coefficients were also computed using mean quality factors based on ICRP 60 and ICRU 49 recommendations. Effective quality factors were then calculated from the ratio of the dose-equivalent to the absorbed dose conversion coefficients for both the personal dose-equivalent and ambient dose-equivalent and compared to values reported in the literature.

  2. Effects of turbulent mixing on critical behaviour: renormalization-group analysis of the Potts model

    NASA Astrophysics Data System (ADS)

    Antonov, N. V.; Malyshev, A. V.

    2012-06-01

    The critical behaviour of a system, subjected to strongly anisotropic turbulent mixing, is studied by means of the field-theoretic renormalization group. Specifically, the relaxational stochastic dynamics of a non-conserved multicomponent order parameter of the Ashkin-Teller-Potts model, coupled to a random velocity field with prescribed statistics, is considered. The velocity is taken to be Gaussian, white in time, with a correlation function of the form ∝δ(t - t‧)/|k⊥|d - 1 + ξ, where k⊥ is the component of the wave vector, perpendicular to the distinguished direction (‘direction of the flow’)—the d-dimensional generalization of the ensemble was introduced by Avellaneda and Majda (1990 Commun. Math. Phys. 131 381) within the context of passive scalar advection. This model can describe a rich class of physical situations. It is shown that, depending on the values of the parameters that define the self-interaction of the order parameter and the relation between the exponent ξ and the space dimension d, the system exhibits various types of large-scale scaling behaviour, associated with different infrared attractive fixed points of the renormalization-group equations. In addition to known asymptotic regimes (critical dynamics of the Potts model and passively advected field without self-interaction), the existence of a new, non-equilibrium and strongly anisotropic, type of critical behaviour (universality class) is established, and the corresponding critical dimensions are calculated to the leading order of the double expansion in ξ and ɛ = 6 - d (one-loop approximation). The scaling appears to be strongly anisotropic in the sense that the critical dimensions related to the directions parallel and perpendicular to the flow are essentially different.

  3. An image-based skeletal tissue model for the ICRP reference newborn.

    PubMed

    Pafundi, Deanna; Lee, Choonsik; Watchman, Christopher; Bourke, Vincent; Aris, John; Shagina, Natalia; Harrison, John; Fell, Tim; Bolch, Wesley

    2009-07-21

    Hybrid phantoms represent a third generation of computational models of human anatomy needed for dose assessment in both external and internal radiation exposures. Recently, we presented the first whole-body hybrid phantom of the ICRP reference newborn with a skeleton constructed from both non-uniform rational B-spline and polygon-mesh surfaces (Lee et al 2007 Phys. Med. Biol. 52 3309-33). The skeleton in that model included regions of cartilage and fibrous connective tissue, with the remainder given as a homogenous mixture of cortical and trabecular bone, active marrow and miscellaneous skeletal tissues. In the present study, we present a comprehensive skeletal tissue model of the ICRP reference newborn to permit a heterogeneous representation of the skeleton in that hybrid phantom set-both male and female-that explicitly includes a delineation of cortical bone so that marrow shielding effects are correctly modeled for low-energy photons incident upon the newborn skeleton. Data sources for the tissue model were threefold. First, skeletal site-dependent volumes of homogeneous bone were obtained from whole-cadaver CT image analyses. Second, selected newborn bone specimens were acquired at autopsy and subjected to micro-CT image analysis to derive model parameters of the marrow cavity and bone trabecular 3D microarchitecture. Third, data given in ICRP Publications 70 and 89 were selected to match reference values on total skeletal tissue mass. Active marrow distributions were found to be in reasonable agreement with those given previously by the ICRP. However, significant differences were seen in total skeletal and site-specific masses of trabecular and cortical bone between the current and ICRP newborn skeletal tissue models. The latter utilizes an age-independent ratio of 80%/20% cortical and trabecular bone for the reference newborn. In the current study, a ratio closer to 40%/60% is used based upon newborn CT and micro-CT skeletal image analyses. These changes in

  4. An image-based skeletal tissue model for the ICRP reference newborn

    NASA Astrophysics Data System (ADS)

    Pafundi, Deanna; Lee, Choonsik; Watchman, Christopher; Bourke, Vincent; Aris, John; Shagina, Natalia; Harrison, John; Fell, Tim; Bolch, Wesley

    2009-07-01

    Hybrid phantoms represent a third generation of computational models of human anatomy needed for dose assessment in both external and internal radiation exposures. Recently, we presented the first whole-body hybrid phantom of the ICRP reference newborn with a skeleton constructed from both non-uniform rational B-spline and polygon-mesh surfaces (Lee et al 2007 Phys. Med. Biol. 52 3309-33). The skeleton in that model included regions of cartilage and fibrous connective tissue, with the remainder given as a homogenous mixture of cortical and trabecular bone, active marrow and miscellaneous skeletal tissues. In the present study, we present a comprehensive skeletal tissue model of the ICRP reference newborn to permit a heterogeneous representation of the skeleton in that hybrid phantom set—both male and female—that explicitly includes a delineation of cortical bone so that marrow shielding effects are correctly modeled for low-energy photons incident upon the newborn skeleton. Data sources for the tissue model were threefold. First, skeletal site-dependent volumes of homogeneous bone were obtained from whole-cadaver CT image analyses. Second, selected newborn bone specimens were acquired at autopsy and subjected to micro-CT image analysis to derive model parameters of the marrow cavity and bone trabecular 3D microarchitecture. Third, data given in ICRP Publications 70 and 89 were selected to match reference values on total skeletal tissue mass. Active marrow distributions were found to be in reasonable agreement with those given previously by the ICRP. However, significant differences were seen in total skeletal and site-specific masses of trabecular and cortical bone between the current and ICRP newborn skeletal tissue models. The latter utilizes an age-independent ratio of 80%/20% cortical and trabecular bone for the reference newborn. In the current study, a ratio closer to 40%/60% is used based upon newborn CT and micro-CT skeletal image analyses. These

  5. E-learning for Critical Thinking: Using Nominal Focus Group Method to Inform Software Content and Design.

    PubMed

    Parker, Steve; Mayner, Lidia; Michael Gillham, David

    2015-12-01

    Undergraduate nursing students are often confused by multiple understandings of critical thinking. In response to this situation, the Critiique for critical thinking (CCT) project was implemented to provide consistent structured guidance about critical thinking. This paper introduces Critiique software, describes initial validation of the content of this critical thinking tool and explores wider applications of the Critiique software. Critiique is flexible, authorable software that guides students step-by-step through critical appraisal of research papers. The spelling of Critiique was deliberate, so as to acquire a unique web domain name and associated logo. The CCT project involved implementation of a modified nominal focus group process with academic staff working together to establish common understandings of critical thinking. Previous work established a consensus about critical thinking in nursing and provided a starting point for the focus groups. The study was conducted at an Australian university campus with the focus group guided by open ended questions. Focus group data established categories of content that academic staff identified as important for teaching critical thinking. This emerging focus group data was then used to inform modification of Critiique software so that students had access to consistent and structured guidance in relation to critical thinking and critical appraisal. The project succeeded in using focus group data from academics to inform software development while at the same time retaining the benefits of broader philosophical dimensions of critical thinking.

  6. E-learning for Critical Thinking: Using Nominal Focus Group Method to Inform Software Content and Design

    PubMed Central

    Parker, Steve; Mayner, Lidia; Michael Gillham, David

    2015-01-01

    Background: Undergraduate nursing students are often confused by multiple understandings of critical thinking. In response to this situation, the Critiique for critical thinking (CCT) project was implemented to provide consistent structured guidance about critical thinking. Objectives: This paper introduces Critiique software, describes initial validation of the content of this critical thinking tool and explores wider applications of the Critiique software. Materials and Methods: Critiique is flexible, authorable software that guides students step-by-step through critical appraisal of research papers. The spelling of Critiique was deliberate, so as to acquire a unique web domain name and associated logo. The CCT project involved implementation of a modified nominal focus group process with academic staff working together to establish common understandings of critical thinking. Previous work established a consensus about critical thinking in nursing and provided a starting point for the focus groups. The study was conducted at an Australian university campus with the focus group guided by open ended questions. Results: Focus group data established categories of content that academic staff identified as important for teaching critical thinking. This emerging focus group data was then used to inform modification of Critiique software so that students had access to consistent and structured guidance in relation to critical thinking and critical appraisal. Conclusions: The project succeeded in using focus group data from academics to inform software development while at the same time retaining the benefits of broader philosophical dimensions of critical thinking. PMID:26835469

  7. Identification of critical paralog groups with indispensable roles in the regulation of signaling flow

    PubMed Central

    Modos, Dezso; Brooks, Johanne; Fazekas, David; Ari, Eszter; Vellai, Tibor; Csermely, Peter; Korcsmaros, Tamas; Lenti, Katalin

    2016-01-01

    Extensive cross-talk between signaling pathways is required to integrate the myriad of extracellular signal combinations at the cellular level. Gene duplication events may lead to the emergence of novel functions, leaving groups of similar genes - termed paralogs - in the genome. To distinguish critical paralog groups (CPGs) from other paralogs in human signaling networks, we developed a signaling network-based method using cross-talk annotation and tissue-specific signaling flow analysis. 75 CPGs were found with higher degree, betweenness centrality, closeness, and ‘bowtieness’ when compared to other paralogs or other proteins in the signaling network. CPGs had higher diversity in all these measures, with more varied biological functions and more specific post-transcriptional regulation than non-critical paralog groups (non-CPG). Using TGF-beta, Notch and MAPK pathways as examples, SMAD2/3, NOTCH1/2/3 and MEK3/6-p38 CPGs were found to regulate the signaling flow of their respective pathways. Additionally, CPGs showed a higher mutation rate in both inherited diseases and cancer, and were enriched in drug targets. In conclusion, the results revealed two distinct types of paralog groups in the signaling network: CPGs and non-CPGs. Thus highlighting the importance of CPGs as compared to non-CPGs in drug discovery and disease pathogenesis. PMID:27922122

  8. Health adaptation policy for climate vulnerable groups: a 'critical computational linguistics' analysis.

    PubMed

    Seidel, Bastian M; Bell, Erica

    2014-11-28

    Many countries are developing or reviewing national adaptation policy for climate change but the extent to which these meet the health needs of vulnerable groups has not been assessed. This study examines the adequacy of such policies for nine known climate-vulnerable groups: people with mental health conditions, Aboriginal people, culturally and linguistically diverse groups, aged people, people with disabilities, rural communities, children, women, and socioeconomically disadvantaged people. The study analyses an exhaustive sample of national adaptation policy documents from Annex 1 ('developed') countries of the United Nations Framework Convention on Climate Change: 20 documents from 12 countries. A 'critical computational linguistics' method was used involving novel software-driven quantitative mapping and traditional critical discourse analysis. The study finds that references to vulnerable groups are relatively little present or non-existent, as well as poorly connected to language about practical strategies and socio-economic contexts, both also little present. The conclusions offer strategies for developing policy that is better informed by a 'social determinants of health' definition of climate vulnerability, consistent with best practice in the literature and global policy prescriptions.

  9. High-precision thermodynamic and critical properties from tensor renormalization-group flows.

    PubMed

    Hinczewski, Michael; Berker, A Nihat

    2008-01-01

    The recently developed tensor renormalization-group (TRG) method provides a highly precise technique for deriving thermodynamic and critical properties of lattice Hamiltonians. The TRG is a local coarse-graining transformation, with the elements of the tensor at each lattice site playing the part of the interactions that undergo the renormalization-group flows. These tensor flows are directly related to the phase diagram structure of the infinite system, with each phase flowing to a distinct surface of fixed points. Fixed-point analysis and summation along the flows give the critical exponents, as well as thermodynamic functions along the entire temperature range. Thus, for the ferromagnetic triangular lattice Ising model, the free energy is calculated to better than 10(-5) along the entire temperature range. Unlike previous position-space renormalization-group methods, the truncation (of the tensor index range D) in this general method converges under straightforward and systematic improvements. Our best results are easily obtained with D=24, corresponding to 4624-dimensional renormalization-group flows.

  10. High-precision thermodynamic and critical properties from tensor renormalization-group flows

    NASA Astrophysics Data System (ADS)

    Hinczewski, Michael; Berker, A. Nihat

    2008-01-01

    The recently developed tensor renormalization-group (TRG) method provides a highly precise technique for deriving thermodynamic and critical properties of lattice Hamiltonians. The TRG is a local coarse-graining transformation, with the elements of the tensor at each lattice site playing the part of the interactions that undergo the renormalization-group flows. These tensor flows are directly related to the phase diagram structure of the infinite system, with each phase flowing to a distinct surface of fixed points. Fixed-point analysis and summation along the flows give the critical exponents, as well as thermodynamic functions along the entire temperature range. Thus, for the ferromagnetic triangular lattice Ising model, the free energy is calculated to better than 10-5 along the entire temperature range. Unlike previous position-space renormalization-group methods, the truncation (of the tensor index range D ) in this general method converges under straightforward and systematic improvements. Our best results are easily obtained with D=24 , corresponding to 4624-dimensional renormalization-group flows.

  11. High-Precision Thermodynamic and Critical Properties from Tensor Renormalization-Group Flows

    NASA Astrophysics Data System (ADS)

    Hinczewski, Michael; Berker, A. Nihat

    2008-03-01

    The recently developed tensor renormalization-group (TRG) method [1] provides a highly precise technique for deriving thermodynamic and critical properties of lattice Hamiltonians. The TRG is a local coarse-graining transformation, with the elements of the tensor at each lattice site playing the part of the interactions that undergo the renormalization-group flows. These tensor flows are directly related [2] to the phase diagram structure of the infinite system, with each phase flowing to a distinct surface of fixed points. Fixed-point analysis and summation along the flows give the critical exponents, as well as thermodynamic functions along the entire temperature range. Thus, for the ferromagnetic triangular lattice Ising model, the free energy is calculated to better than 10-5 along the entire temperature range. Unlike previous position-space renormalization-group methods, the truncation (of the tensor index range D) in this general method converges under straightforward and systematic improvements. Our best results are easily obtained with D=24, corresponding to 4624-dimensional renormalization-group flows. [1] M. Levin and C.P. Nave, Phys. Rev. Lett. 99, 120601 (2007). [2] M. Hinczewski and A.N. Berker, arXiv:0709.2803v1 [cond-mat.stat-mech], Phys. Rev. E, in press.

  12. Identification of critical paralog groups with indispensable roles in the regulation of signaling flow.

    PubMed

    Modos, Dezso; Brooks, Johanne; Fazekas, David; Ari, Eszter; Vellai, Tibor; Csermely, Peter; Korcsmaros, Tamas; Lenti, Katalin

    2016-12-06

    Extensive cross-talk between signaling pathways is required to integrate the myriad of extracellular signal combinations at the cellular level. Gene duplication events may lead to the emergence of novel functions, leaving groups of similar genes - termed paralogs - in the genome. To distinguish critical paralog groups (CPGs) from other paralogs in human signaling networks, we developed a signaling network-based method using cross-talk annotation and tissue-specific signaling flow analysis. 75 CPGs were found with higher degree, betweenness centrality, closeness, and 'bowtieness' when compared to other paralogs or other proteins in the signaling network. CPGs had higher diversity in all these measures, with more varied biological functions and more specific post-transcriptional regulation than non-critical paralog groups (non-CPG). Using TGF-beta, Notch and MAPK pathways as examples, SMAD2/3, NOTCH1/2/3 and MEK3/6-p38 CPGs were found to regulate the signaling flow of their respective pathways. Additionally, CPGs showed a higher mutation rate in both inherited diseases and cancer, and were enriched in drug targets. In conclusion, the results revealed two distinct types of paralog groups in the signaling network: CPGs and non-CPGs. Thus highlighting the importance of CPGs as compared to non-CPGs in drug discovery and disease pathogenesis.

  13. How does group antenatal care function within a caseload midwifery model? A critical ethnographic analysis.

    PubMed

    Allen, J; Kildea, S; Stapleton, H

    2015-05-01

    caseload midwifery and CenteringPregnancy™ (a form of group antenatal care) are two models of maternity care that are separately associated with better clinical outcomes, maternal satisfaction scores and positive experiences compared to standard care. One study reported exclusively on younger women׳s experiences of caseload midwifery; none described younger women׳s experiences of group antenatal care. We retrieved no studies on the experiences of women who received a combination of caseload midwifery and group antenatal care. examine younger women׳s experiences of caseload midwifery in a setting that incorporates group antenatal care. a critical, focused ethnographic approach. the study was conducted in an Australian hospital and its associated community venue from 2011 to 2013. purposive sampling of younger (19-22 years) pregnant and postnatal women (n=10) and the caseload midwives (n=4) who provided group antenatal care within one midwifery group practice. separate focus group interviews with women and caseload midwives, observations of the setting and delivery of group antenatal care, and examination of selected documents. Thematic analyses of the women׳s accounts have been given primary significance. Coded segments of the midwives interview data, field notes and documents were used to compare and contrast within these themes. we report on women׳s first encounters with the group, and their interactions with peers and midwives. The group setting minimised the opportunity for the women and midwives to get to know each other. this study challenges the practice of combining group antenatal care with caseload midwifery and recommends further research. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Numerical renormalization group for impurity quantum phase transitions: structure of critical fixed points

    NASA Astrophysics Data System (ADS)

    Lee, Hyun-Jung; Bulla, Ralf; Vojta, Matthias

    2005-11-01

    The numerical renormalization group method is used to investigate zero-temperature phase transitions in quantum impurity systems, in particular in the particle-hole symmetric soft-gap Anderson model. The model displays two stable phases whose fixed points can be built up of non-interacting single-particle states. In contrast, the quantum phase transitions turn out to be described by interacting fixed points, and their excitations cannot be described in terms of free particles. We show that the structure of the many-body spectrum of these critical fixed points can be understood using renormalized perturbation theory close to certain values of the bath exponents which play the role of critical dimensions. Contact is made with perturbative renormalization group calculations for the soft-gap Anderson and Kondo models. A complete description of the quantum critical many-particle spectra is achieved using suitable marginal operators; technically this can be understood as epsilon-expansion for full many-body spectra.

  15. Making the Road by Walking and Talking: Critical Literacy and/as Professional Development in a Teacher Inquiry Group

    ERIC Educational Resources Information Center

    Luna, Cathy; Botelho, Maria Jose; Fontaine, Dawn; French, Kristen; Iverson, Kris; Matos, Nelida

    2004-01-01

    This article offers a description of critical literacy practice and/as professional development as it evolved in a teacher inquiry group investigating critical literacy. The authors describe this professional development experience as an instance of critical literacy in practice. The entirety of this article is a collaborative product in which the…

  16. Comment on ``Renormalization-group picture of the Lifshitz critical behavior''

    NASA Astrophysics Data System (ADS)

    Diehl, H. W.; Shpot, M.

    2003-08-01

    We show that the recent renormalization-group analysis of Lifshitz critical behavior presented by Leite [Phys. Rev. B 67, 104415 (2003)] suffers from a number of severe deficiencies. In particular, we show that his approach does not give an ultraviolet finite renormalized theory, is plagued by inconsistencies, misses the existence of a nontrivial anisotropy exponent θ≠1/2, and therefore yields incorrect hyperscaling relations. His ɛ-expansion results to order ɛ2 for the critical exponents of m-axial Lifshitz points are incorrect in both the anisotropic (0

  17. A Renormalization-Group Interpretation of the Connection between Criticality and Multifractals

    NASA Astrophysics Data System (ADS)

    Chang, Tom

    2014-05-01

    Turbulent fluctuations in space plasmas beget phenomena of dynamic complexity. It is known that dynamic renormalization group (DRG) may be employed to understand the concept of forced and/or self-organized criticality (FSOC), which seems to describe certain scaling features of space plasma turbulence. But, it may be argued that dynamic complexity is not just a phenomenon of criticality. It is therefore of interest to inquire if DRG may be employed to study complexity phenomena that are distinctly more complicated than dynamic criticality. Power law scaling generally comes about when the DRG trajectory is attracted to the vicinity of a fixed point in the phase space of the relevant dynamic plasma parameters. What happens if the trajectory lies within a domain influenced by more than one single fixed point or more generally if the transformation underlying the DRG is fully nonlinear? The global invariants of the group under such situations (if they exist) are generally not power laws. Nevertheless, as we shall argue, it may still be possible to talk about local invariants that are power laws with the nonlinearity of transformation prescribing a specific phenomenon as crossovers. It is with such concept in mind that we may provide a connection between the properties of dynamic criticality and multifractals from the point of view of DRG (T. Chang, Chapter VII, "An Introduction to Space Plasma Complexity", Cambridge University Press, 2014). An example in terms of the concepts of finite-size scaling (FSS) and rank-ordered multifractal analysis (ROMA) of a toy model shall be provided. Research partially supported by the US National Science Foundation and the European Community's Seventh Framework Programme (FP7/ 2007-2013) under Grant agreement no. 313038/STORM.

  18. Functional renormalization group analysis of the soft mode at the QCD critical point

    NASA Astrophysics Data System (ADS)

    Yokota, Takeru; Kunihiro, Teiji; Morita, Kenji

    2016-07-01

    We make an intensive investigation of the soft mode at the quantum chromodynamics (QCD) critical point on the basis of the functional renormalization group (FRG) method in the local potential approximation. We calculate the spectral functions ρ_{σ, π}(ω, p) in the scalar (σ) and pseudoscalar (π) channels beyond the random phase approximation in the quark-meson model. At finite baryon chemical potential μ with a finite quark mass, the baryon-number fluctuation is coupled to the scalar channel and the spectral function in the σ channel has a support not only in the time-like (ω > p) but also in the space-like (ω < p) regions, which correspond to the mesonic and the particle-hole phonon excitations, respectively. We find that the energy of the peak position of the latter becomes vanishingly small with the height being enhanced as the system approaches the QCD critical point, which is a manifestation of the fact that the phonon mode is the soft mode associated with the second-order transition at the QCD critical point, as has been suggested by some authors. Moreover, our extensive calculation of the spectral function in the (ω, p) plane enables us to see that the mesonic and phonon modes have the respective definite dispersion relations ω_{σ.ph}(p), and it turns out that ω_{σ}(p) crosses the light-cone line into the space-like region, and then eventually merges into the phonon mode as the system approaches the critical point more closely. This implies that the sigma-mesonic mode also becomes soft at the critical point. We also provide numerical stability conditions that are necessary for obtaining the accurate effective potential from the flow equation.

  19. A group randomized trial of critical incident stress debriefing provided to U.S. peacekeepers.

    PubMed

    Adler, Amy B; Litz, Brett T; Castro, Carl Andrew; Suvak, Michael; Thomas, Jeffrey L; Burrell, Lolita; McGurk, Dennis; Wright, Kathleen M; Bliese, Paul D

    2008-06-01

    In a group randomized trial of critical incident stress debriefing (CISD) with platoons of 952 peacekeepers, CISD was compared with a stress management class (SMC) and survey-only (SO) condition. Multilevel growth curve modeling found that CISD did not differentially hasten recovery compared to the other two conditions. For those soldiers reporting the highest degree of exposure to mission stressors, CISD was minimally associated with lower reports of posttraumatic stress and aggression (vs. SMC), higher perceived organizational support (vs. SO), and more alcohol problems than SMC and SO. Soldiers reported that they liked CISD more than the SMC, and CISD did not cause undue distress.

  20. Aromatic hydroxyl group plays a critical role in antibacterial activity of the curcumin analogues.

    PubMed

    Kim, Mi Kyoung; Park, Jun Cheol; Chong, Youhoon

    2012-01-01

    The aim of this study was to investigate the role of the aromatic substituents of the curcumin scaffold on the antibacterial activity of the resulting curcumin analogues. Six curcumin analogues with different aromatic substituents were prepared and their antibacterial activities were evaluated against two Gram-positive and four Gram-negative bacteria. The structure-activity relationship study demonstrated that antibacterial activity of the curcumin analogues was critically dependent upon the aromatic hydroxyl group. Thus, hydroxycurcumin with an additional aromatic hydroxyl group on the curcumin scaffold showed antibacterial activity against all six pathogens tested and it remained effective even against ampicillin-resistant Enterobacter cloacae. Along with the previously reported antioxidative effect, the broad-spectrum antibacterial activity of the hydroxycurcumin warrants further investigation of its biological activity as well as extensive structure-activity relationship study of the curcumin analogues with various aromatic substituents.

  1. Who says we are bad people? The impact of criticism source and attributional content on responses to group-based criticism.

    PubMed

    Rabinovich, Anna; Morton, Thomas A

    2010-04-01

    We investigated the interplay between the source of criticism and the attributional content of their message on behavioral responses to group-based criticism. Studies 1 and 2 revealed that outgroup critics were more effective when their criticism included internal attributions (to the ingroup's character) rather than external attributions (the ingroup's circumstances), whereas there was no effect of attributional content for ingroup critics (a significant Source x Content interaction). Study 3 explored the role of audiences in responses to outgroup criticism. The results indicated that the positive effects of internal versus external attributions were only evident when an outgroup audience was witness to participants' responses. Furthermore, these effects were mediated through concerns about the ingroup's image. Together, these patterns suggest that responses to criticism depend not just on the identity of the critic but also on what the critic says and who is watching. People may be surprisingly responsive to outgroup criticism-particularly when inaction might lead others to perceive them as "bad people."

  2. Biosphere Dose Conversion Factors for Reasonably Maximally Exposed Individual and Average Member of Critical Group

    SciTech Connect

    K. Montague

    2000-02-23

    The purpose of this calculation is to develop additional Biosphere Dose Conversion Factors (BDCFs) for a reasonably maximally exposed individual (RMEI) for the periods 10,000 years and 1,000,000 years after the repository closure. In addition, Biosphere Dose Conversion Factors for the average member of a critical group are calculated for those additional radionuclides postulated to reach the environment during the period after 10,000 years and up to 1,000,000 years. After the permanent closure of the repository, the engineered systems within the repository will eventually lose their abilities to contain radionuclide inventory, and the radionuclides will migrate through the geosphere and eventually enter the local water table moving toward inhabited areas. The primary release scenario is a groundwater well used for drinking water supply and irrigation, and this calculation takes these postulated releases and follows them through various pathways until they result in a dose to either a member of critical group or a reasonably maximally exposed individual. The pathways considered in this calculation include inhalation, ingestion, and direct exposure.

  3. Workshop to identify critical windows of exposure for children's health: neurobehavioral work group summary.

    PubMed Central

    Adams, J; Barone, S; LaMantia, A; Philen, R; Rice, D C; Spear, L; Susser, E

    2000-01-01

    This paper summarizes the deliberations of a work group charged with addressing specific questions relevant to risk estimation in developmental neurotoxicology. We focused on eight questions. a) Does it make sense to think about discrete windows of vulnerability in the development of the nervous system? If it does, which time periods are of greatest importance? b) Are there cascades of developmental disorders in the nervous system? For example, are there critical points that determine the course of development that can lead to differences in vulnerabilities at later times? c) Can information on critical windows suggest the most susceptible subgroups of children (i.e., age groups, socioeconomic status, geographic areas, race, etc.)? d) What are the gaps in existing data for the nervous system or end points of exposure to it? e) What are the best ways to examine exposure-response relationships and estimate exposures in vulnerable life stages? f) What other exposures that affect development at certain ages may interact with exposures of concern? g) How well do laboratory animal data predict human response? h) How can all of this information be used to improve risk assessment and public health (risk management)? In addressing these questions, we provide a brief overview of brain development from conception through adolescence and emphasize vulnerability to toxic insult throughout this period. Methodological issues focus on major variables that influence exposure or its detection through disruptions of behavior, neuroanatomy, or neurochemical end points. Supportive evidence from studies of major neurotoxicants is provided. PMID:10852852

  4. Dose estimate of inhaled hafnium tritide using the ICRP 66 lung model.

    PubMed

    Cheng, Yung-Sung; Zhou, Yue; Wang, Yang-Sheng; Inkret, William C; Wermer, Joseph R

    2002-06-01

    Metal tritide is widely used for research, purification, compression, and storage of tritium. The current understanding of metal tritide and its radiation dosimetry for internal exposure is limited, and ICRP publications do not provide the tritium dosimetry for hafnium tritide. The current radiation protection guidelines for metal tritide particles (including hafnium tritide) are based on the assumption that their biological behavior is similar to tritiated water, which is completely absorbed by the body. However, the solubility of metal tritide particles depends on the chemical form of the material. The biological half-live of hafnium tritide particles and the dosimetry of an inhalation exposure to those particles could be quite different from tritiated water. This paper describes experiments on the dissolution rate of hafnium tritide particles in a simulated lung fluid. The results showed that less than 1% of the tritium was dissolved in the simulated lung fluid for hafnium tritide particles after 215 d. The short-term and long-term dissolution half times were 46 and 4.28 x 10(5) d, respectively. This indicates that hafnium tritide is an extremely insoluble material. Self-absorption of beta rays in the hafnium tritide particles was estimated by a numerical method. The dose coefficients were calculated as a function of particle size using in vitro solubility data and a calculated self-absorption factor. The dose coefficient decreased with aerodynamic diameters in the range of 0.25 to 10 microm, mainly because the self-absorption factor decreased with increasing particle size. For a particle 1 microm in aerodynamic diameter, the dose coefficient of a hafnium tritide particle was about 10 times higher than that of tritiated water but was about 1.4 times lower than that calculated by ICRP Publication 71 for Type S tritiated particles. The ICRP estimate did not include a self-absorption factor and thus might have overestimated the dose. This finding has significant

  5. Selected organ dose conversion coefficients for external photons calculated using ICRP adult voxel phantoms and Monte Carlo code FLUKA.

    PubMed

    Patni, H K; Nadar, M Y; Akar, D K; Bhati, S; Sarkar, P K

    2011-11-01

    The adult reference male and female computational voxel phantoms recommended by ICRP are adapted into the Monte Carlo transport code FLUKA. The FLUKA code is then utilised for computation of dose conversion coefficients (DCCs) expressed in absorbed dose per air kerma free-in-air for colon, lungs, stomach wall, breast, gonads, urinary bladder, oesophagus, liver and thyroid due to a broad parallel beam of mono-energetic photons impinging in anterior-posterior and posterior-anterior directions in the energy range of 15 keV-10 MeV. The computed DCCs of colon, lungs, stomach wall and breast are found to be in good agreement with the results published in ICRP publication 110. The present work thus validates the use of FLUKA code in computation of organ DCCs for photons using ICRP adult voxel phantoms. Further, the DCCs for gonads, urinary bladder, oesophagus, liver and thyroid are evaluated and compared with results published in ICRP 74 in the above-mentioned energy range and geometries. Significant differences in DCCs are observed for breast, testis and thyroid above 1 MeV, and for most of the organs at energies below 60 keV in comparison with the results published in ICRP 74. The DCCs of female voxel phantom were found to be higher in comparison with male phantom for almost all organs in both the geometries.

  6. Group critical incident stress debriefing with emergency services personnel: a randomized controlled trial.

    PubMed

    Tuckey, Michelle R; Scott, Jill E

    2014-01-01

    Although single-session individual debriefing is contraindicated, the efficacy of group psychological debriefing remains unresolved. We conducted the first randomized controlled trial of critical incident stress debriefing (CISD) with emergency workers (67 volunteer fire-fighters) following shared exposure to an occupational potentially traumatic event (PTE). The goals of group CISD are to prevent post-traumatic stress and promote return to normal functioning following a PTE. To assess both goals we measured four outcomes, before and after the intervention: post-traumatic stress, psychological distress, quality of life, and alcohol use. Fire brigades were randomly assigned to one of three treatment conditions: (1) CISD, (2) Screening (i.e., no-treatment), or (3) stress management Education. Controlling for pre-intervention scores, CISD was associated with significantly less alcohol use post-intervention relative to Screening, and significantly greater post-intervention quality of life relative to Education. There were no significant effects on post-traumatic stress or psychological distress. Overall, CISD may benefit broader functioning following exposure to work-related PTEs. Future research should focus on individual, group, and organizational factors and processes that can promote recovery from operational stressors. Ultimately, an occupational health (rather than victim-based) approach will provide the best framework for understanding and combating potential threats to the health and well-being of workers at high risk for PTE exposure.

  7. Group-directed criticisms and recommendations for change: why newcomers arouse more resistance than old-timers.

    PubMed

    Hornsey, Matthew J; Grice, Tim; Jetten, Jolanda; Paulsen, Neil; Callan, Victor

    2007-07-01

    Three experiments examine the extent to which newcomers are able to influence their groups relative to old-timers. Specifically, how group members respond to criticisms of their group was assessed as a function of the intragroup position of the speaker. When criticizing their workplace (Experiment 1; N = 116), their profession (Experiment 2; N = 106), or an Internet community (Experiment 3; N = 189), newcomers aroused more resistance than old-timers, an effect that was mediated by perceptions of how attached critics were to their group identity. Experiment 3 also showed that newcomers could reduce resistance to their criticisms by distancing themselves from a group of which they were previously members. Theoretical and practical implications of these findings are discussed.

  8. Radiation safety concerns for pregnant or breast feeding patients. The positions of the NCRP and the ICRP

    SciTech Connect

    Meinhold, C.B.

    1997-01-01

    For many years, protecting the fetus has been a concern of the National Council on Radiation Protection and Measurements (NCRP) and the International Commission on Radiological Protection (ICRP). Early recommendations focused on the possibility of a wide variety of detrimental developmental effects while later recommendations focused on the potential for severe mental retardation and/or reduction in the intelligence quotient (I.Q.). The latest recommendations also note that the risk of cancer for the fetus is probably two to three times greater per Sv than in the adult. For all these reasons, the NCRP and the ICRP have provided guidance to physicians on taking all reasonable steps to ascertain whether any woman requiring a radiological or nuclear medicine procedure is pregnant or nursing a child. The NCRP and the ICRP also advise the clinician to postpone such procedures until after delivery or cessation of nursing, if possible.

  9. New real-space renormalization-group calculation for the critical properties of lattice spin systems

    NASA Astrophysics Data System (ADS)

    Hecht, Charles E.; Kikuchi, Ryoichi

    1982-05-01

    In evaluating the critical properties of lattice spin systems in the real-space renormalization-group theory we use the cluster variation method. A configuration in the transformed system is constrained and the probability of occurrence of this configuration is calculated both in the transformed system and in the original system. By equating the two probabilities and forming ratios of two such equalities (for two or more constrained configurations) the fixed point of the renormalization transformation is evaluated. The method can avoid the trouble due to different singularities in the original and transformed systems, and hence can obviate the possible development of spurious singularities in the transformation at low temperatures. The two-dimensional triangular Ising model is treated with numerical results comparable with those obtained by the cluster treatment of Niemeijer and van Leeuwen who used more and larger cluster types than those we introduce.

  10. Critical Point Facility (CPE) Group in the Spacelab Payload Operations Control Center (SL POCC)

    NASA Technical Reports Server (NTRS)

    1992-01-01

    The primary payload for Space Shuttle Mission STS-42, launched January 22, 1992, was the International Microgravity Laboratory-1 (IML-1), a pressurized manned Spacelab module. The goal of IML-1 was to explore in depth the complex effects of weightlessness of living organisms and materials processing. Around-the-clock research was performed on the human nervous system's adaptation to low gravity and effects of microgravity on other life forms such as shrimp eggs, lentil seedlings, fruit fly eggs, and bacteria. Materials processing experiments were also conducted, including crystal growth from a variety of substances such as enzymes, mercury iodide, and a virus. The Huntsville Operations Support Center (HOSC) Spacelab Payload Operations Control Center (SL POCC) at the Marshall Space Flight Center (MSFC) was the air/ground communication channel used between the astronauts and ground control teams during the Spacelab missions. Featured is the Critical Point Facility (CPE) group in the SL POCC during STS-42, IML-1 mission.

  11. Critical Point Facility (CPE) Group in the Spacelab Payload Operations Control Center (SL POCC)

    NASA Technical Reports Server (NTRS)

    1992-01-01

    The primary payload for Space Shuttle Mission STS-42, launched January 22, 1992, was the International Microgravity Laboratory-1 (IML-1), a pressurized manned Spacelab module. The goal of IML-1 was to explore in depth the complex effects of weightlessness of living organisms and materials processing. Around-the-clock research was performed on the human nervous system's adaptation to low gravity and effects of microgravity on other life forms such as shrimp eggs, lentil seedlings, fruit fly eggs, and bacteria. Materials processing experiments were also conducted, including crystal growth from a variety of substances such as enzymes, mercury iodide, and a virus. The Huntsville Operations Support Center (HOSC) Spacelab Payload Operations Control Center (SL POCC) at the Marshall Space Flight Center (MSFC) was the air/ground communication channel used between the astronauts and ground control teams during the Spacelab missions. Featured is the Critical Point Facility (CPE) group in the SL POCC during STS-42, IML-1 mission.

  12. ICRP's approach to protection of the living environment under different exposure situations.

    PubMed

    Pentreath, R J; Larsson, C-M; Copplestone, D

    2015-06-01

    The International Commission on Radiological Protection's (ICRP) system to protect the living components of the environment is designed to provide a broad and practical framework across all exposure situations. The objectives of ICRP are therefore also set in fairly broad terms, recognising that national and local environmental protection requirements may need to be set within them. The framework recognises the need to be able to demonstrate an adequate level of protection in relation to planned exposure situations, whilst also providing an ability to manage existing situations and accidents, as well as emergency situations, in a rational way. The objects of protection are always real biota in real exposure situations, and the scientific basis for their protection needs to be based on data originating from studies on the relationships between exposure and dose, dose and effects, and effects and consequences in real animals and plants. The framework that has been developed has therefore had to take such realities into account to make the optimum use of the data currently available, whilst being sufficiently flexible to accommodate new scientific information as it arises without having to alter the framework as a whole.

  13. Radiochemical approach to the JCO criticality accident in Tokai-mura, 1999--an overview of the radiochemistry group.

    PubMed

    Komura, K

    2001-09-01

    A few days after the JCO criticality accident in Tokai-mura, a collaborating scientific investigation group was organized to evaluate the environmental impact of the accident. The group consisted of two groups: an environmental research group (radiochemistry group) and a biological research group. This paper overviews the scientific activity of the former group based on 6 sampling campaigns conducted at the JCO campus, Tokai-mura and Naka-machi. Some of the topical results and our remaining tasks concerning the JCO accident are discussed.

  14. Applying Critical Race Theory to Group Model Building Methods to Address Community Violence.

    PubMed

    Frerichs, Leah; Lich, Kristen Hassmiller; Funchess, Melanie; Burrell, Marcus; Cerulli, Catherine; Bedell, Precious; White, Ann Marie

    2016-01-01

    Group model building (GMB) is an approach to building qualitative and quantitative models with stakeholders to learn about the interrelationships among multilevel factors causing complex public health problems over time. Scant literature exists on adapting this method to address public health issues that involve racial dynamics. This study's objectives are to (1) introduce GMB methods, (2) present a framework for adapting GMB to enhance cultural responsiveness, and (3) describe outcomes of adapting GMB to incorporate differences in racial socialization during a community project seeking to understand key determinants of community violence transmission. An academic-community partnership planned a 1-day session with diverse stakeholders to explore the issue of violence using GMB. We documented key questions inspired by critical race theory (CRT) and adaptations to established GMB "scripts" (i.e., published facilitation instructions). The theory's emphasis on experiential knowledge led to a narrative-based facilitation guide from which participants created causal loop diagrams. These early diagrams depict how violence is transmitted and how communities respond, based on participants' lived experiences and mental models of causation that grew to include factors associated with race. Participants found these methods useful for advancing difficult discussion. The resulting diagrams can be tested and expanded in future research, and will form the foundation for collaborative identification of solutions to build community resilience. GMB is a promising strategy that community partnerships should consider when addressing complex health issues; our experience adapting methods based on CRT is promising in its acceptability and early system insights.

  15. The effect of acidified enteral feeds on gastric colonization in critically ill patients: results of a multicenter randomized trial. Canadian Critical Care Trials Group.

    PubMed

    Heyland, D K; Cook, D J; Schoenfeld, P S; Frietag, A; Varon, J; Wood, G

    1999-11-01

    To evaluate the effect of acidified enteral feeds on gastric colonization in critically ill patients compared with a standard feeding formula. Randomized, double-blind, multicenter trial. Eight mixed intensive care units at tertiary care hospitals. We recruited mechanically ventilated critically ill patients expected to remain ventilated for >48 hrs. We excluded patients with gastrointestinal bleeding, acidemia, and renal failure requiring dialysis. We enrolled 120 patients; 38% were female, age (mean +/- SD) was 57.6+/-19.3 yrs, and Acute Physiology and Chronic Health Evaluation II score (mean +/- SD) was 21.6+/-7.6. Vital High Nitrogen (Abbott Laboratories, Ross Products Division, Columbus, OH) was used as the standard feeding formula for the control group (pH = 6.5). Hydrochloric acid was added to Vital High Nitrogen to achieve a pH of 3.5 in the experimental group. The main outcome measure was gastric colonization. Secondary outcomes included gastric pH, pneumonia, and mortality. The mean gastric pH in patients receiving acid feeds was lower (pH = 3.3) compared with controls (pH = 4.6; p<.05). One patient (2%) on acid feeds was colonized in the stomach with pathogenic bacteria, compared with 20 patients (43%) in the control group (p<.001). There was no difference in the incidence of pneumonia (6.1% in the acid feeds group vs. 15% in the control group; p = .19). Overall, there were 15 deaths in the acid feeds group and seven in the control group (p = .10); four patients in the acid feeds group and three in the control group died during the study period (p not significant). Acidified enteral feeds preserve gastric acidity and substantially reduce gastric colonization in critically ill patients. Larger studies are needed to examine its effect on ventilator-associated pneumonia and mortality.

  16. Derived Intervention Levels for Tritium Based on Food and Drug Administration Methodology Using ICRP 56 Dose Coefficients

    SciTech Connect

    Blanchard, A

    1999-06-09

    In 1998, the FDA released its recommendations for age-dependent derived intervention levels for several radionuclides involved in nuclear accidents. One radionuclide that is not included in that document is tritium. Therefore an analysis is presented here using dose coefficients from ICRP 56 to develop Derived Intervention Levels (DILs) for tritium in two forms: water (HTO) and organically bound tritium (OBT).

  17. Swimming Training Assessment: The Critical Velocity and the 400-m Test for Age-Group Swimmers.

    PubMed

    Zacca, Rodrigo; Fernandes, Ricardo Jorge P; Pyne, David B; Castro, Flávio Antônio de S

    2016-05-01

    To verify the metabolic responses of oxygen consumption (V[Combining Dot Above]O2), heart rate (HR), blood lactate concentrations [La], and rate of perceived exertion (RPE) when swimming at an intensity corresponding to the critical velocity (CV) assessed by a 4-parameter model (CV4par), and to check the reliability when using only a single 400-m maximal front crawl bout (T400) for CV4par assessment in age-group swimmers. Ten age-group swimmers (14-16 years old) performed 50-, 100-, 200-, 400- (T400), 800-, and 1,500-m maximal front crawl bouts to calculate CV4par. V[Combining Dot Above]O2, HR, [La], and RPE were measured immediately after bouts. Swimmers then performed 3 × 10-minute front crawl (45 seconds rest) at CV4par. V[Combining Dot Above]O2, HR, [La], and RPE were measured after 10 minutes of rest (Rest), warm-up (Pre), each 10-minute repetition, and at the end of the test (Post). CV4par was 1.33 ± 0.08 m·s. V[Combining Dot Above]O2, HR, [La], and RPE were similar between first 10-minute and Post time points in the 3 × 10-minute protocol. CV4par was equivalent to 92 ± 2% of the mean swimming speed of T400 (v400) for these swimmers. CV4par calculated through a single T400 (92%v400) showed excellent agreement (r = 0.30; 95% CI: -0.04 to 0.05 m·s, p = 0.39), low coefficient of variation (2%), and root mean square error of 0.02 ± 0.01 m·s when plotted against CV4par assessed through a 4-parameter model. These results generated the equation CV4par = 0.92 × v400. A single T400 can be used reliably to estimate the CV4par typically derived with 6 efforts in age-group swimmers.

  18. Reply to ``Comment on `Renormalization-group picture of the Lifshitz critical behavior' ''

    NASA Astrophysics Data System (ADS)

    Leite, Marcelo M.

    2003-08-01

    We reply to the preceding Comment by Diehl and Shpot [Phys. Rev. B 68, 066401 (2003)] criticizing a new approach to the Lifshitz critical behavior just presented [M. M. Leite, Phys. Rev. B 67, 104415 (2003)]. We show that this approach is free of inconsistencies in the ultraviolet regime. We recall that the orthogonal approximation employed to solve arbitrary loop diagrams worked out in the criticized paper even at the three-loop level is consistent with homogeneity for arbitrary loop momenta. We show that the criticism is incorrect.

  19. Radiological Protection in Cone Beam Computed Tomography (CBCT). ICRP Publication 129.

    PubMed

    Rehani, M M; Gupta, R; Bartling, S; Sharp, G C; Pauwels, R; Berris, T; Boone, J M

    2015-07-01

    The objective of this publication is to provide guidance on radiological protection in the new technology of cone beam computed tomography (CBCT). Publications 87 and 102 dealt with patient dose management in computed tomography (CT) and multi-detector CT. The new applications of CBCT and the associated radiological protection issues are substantially different from those of conventional CT. The perception that CBCT involves lower doses was only true in initial applications. CBCT is now used widely by specialists who have little or no training in radiological protection. This publication provides recommendations on radiation dose management directed at different stakeholders, and covers principles of radiological protection, training, and quality assurance aspects. Advice on appropriate use of CBCT needs to be made widely available. Advice on optimisation of protection when using CBCT equipment needs to be strengthened, particularly with respect to the use of newer features of the equipment. Manufacturers should standardise radiation dose displays on CBCT equipment to assist users in optimisation of protection and comparisons of performance. Additional challenges to radiological protection are introduced when CBCT-capable equipment is used for both fluoroscopy and tomography during the same procedure. Standardised methods need to be established for tracking and reporting of patient radiation doses from these procedures. The recommendations provided in this publication may evolve in the future as CBCT equipment and applications evolve. As with previous ICRP publications, the Commission hopes that imaging professionals, medical physicists, and manufacturers will use the guidelines and recommendations provided in this publication for implementation of the Commission's principle of optimisation of protection of patients and medical workers, with the objective of keeping exposures as low as reasonably achievable, taking into account economic and societal factors, and

  20. Field-theoretical Renormalization-Group approach to critical dynamics of crosslinked polymer blends

    NASA Astrophysics Data System (ADS)

    Benhamou, M.; Chahid, M.

    2008-09-01

    We consider a crosslinked polymer blend that may undergo a microphase separation. When the temperature is changed from an initial value towards a final one very close to the spinodal point, the mixture is out equilibrium. The aim is the study of dynamics at a given time t , before the system reaches its final equilibrium state. The dynamics is investigated through the structure factor, S(q, t) , which is a function of the wave vector q , temperature T , time t , and reticulation dose D . To determine the phase behavior of this dynamic structure factor, we start from a generalized Langevin equation (model C) solved by the time composition fluctuation. Beside the standard de Gennes Hamiltonian, this equation incorporates a Gaussian local noise, ζ . First, by averaging over ζ , we get an effective Hamiltonian. Second, we renormalize this dynamic field theory and write a Renormalization-Group equation for the dynamic structure factor. Third, solving this equation yields the behavior of S(q, t) , in space of relevant parameters. As result, S(q, t) depends on three kinds of lengths, which are the wavelength q-1, a time length scale R(t) thicksim t1/z , and the mesh size ξ* . The scale R(t) is interpreted as the size of growing microdomains at time t . When R(t) becomes of the order of ξ* , the dynamics is stopped. The final time, t * , then scales as t * thicksim ξ{ast z} , with the dynamic exponent z = 6 - η . Here, η is the usual Ising critical exponent. Since the final size of microdomains ξ* is very small (few nanometers), the dynamics is of short time. Finally, all these results we obtained from renormalization theory are compared to those we stated in some recent work using a scaling argument.

  1. Recommendations of the Working Groups from the Spanish Society of Intensive and Critical Care Medicine and Coronary Units (SEMICYUC) for the management of adult critically ill patients.

    PubMed

    Hernández-Tejedor, A; Peñuelas, O; Sirgo Rodríguez, G; Llompart-Pou, J A; Palencia Herrejón, E; Estella, A; Fuset Cabanes, M P; Alcalá-Llorente, M A; Ramírez Galleymore, P; Obón Azuara, B; Lorente Balanza, J A; Vaquerizo Alonso, C; Ballesteros Sanz, M A; García García, M; Caballero López, J; Socias Mir, A; Serrano Lázaro, A; Pérez Villares, J M; Herrera-Gutiérrez, M E

    The standardization of the Intensive Care Medicine may improve the management of the adult critically ill patient. However, these strategies have not been widely applied in the Intensive Care Units (ICUs). The aim is to elaborate the recommendations for the standardization of the treatment of critical patients. A panel of experts from the thirteen working groups (WG) of the Spanish Society of Intensive and Critical Care Medicine and Coronary Units (SEMICYUC) was selected and nominated by virtue of clinical expertise and/or scientific experience to carry out the recommendations. Available scientific literature in the management of adult critically ill patients from 2002 to 2016 was extracted. The clinical evidence was discussed and summarised by the experts in the course of a consensus finding of every WG and finally approved by the WGs after an extensive internal review process that was carried out between December 2015 and December 2016. A total of 65 recommendations were developed, of which 5 corresponded to each of the 13 WGs. These recommendations are based on the opinion of experts and scientific knowledge, and are intended as a guide for the intensivists in the management of critical patients. Copyright © 2017 Elsevier España, S.L.U. y SEMICYUC. All rights reserved.

  2. Critical and strategic materials proceedings of the laboratory study group meeting

    SciTech Connect

    Not Available

    1983-06-01

    These Proceedings serve to identify the appropriate role for the DOE-BES-DMS Laboratory program concerning critical and strategic materials, identify and articulate high priority DOE-BES-DMS target areas so as to maximize programmatic responsiveness to national needs concerning critical and strategic materials, and identify research, expertise, and resources (including Collaborative Research Centers) that are relevant to critical and strategic materials that is either underway or in place under the DOE-BES-DMS Laboratory program. Laboratory statements of collaborative research are given.

  3. On the Spacer Group Effect on Critical Micelle Concentration of Cationic Gemini Surfactants Using Molecular Connectivity Indices.

    PubMed

    Mozrzymas, Anna

    2016-01-01

    The important factor which differentiates gemini surfactants from conventional monomeric surfactants is the spacer group. The molecular connectivity method was used to study the effect of the spacer group on critical micelle concentration of cationic gemini surfactants. Two models were derived employing only Kier and Hall molecular connectivity indices. The relationships were developed for a set of 17 gemini surfactants with various spacer groups only. These models can be used to design the structure of the spacer group and in consequence novel cationic gemini surfactants more active in micelle formation.

  4. Influences of parameter uncertainties within the ICRP-66 respiratory tract model: particle clearance.

    PubMed

    Bolch, Wesley E; Huston, Thomas E; Farfán, Eduardo B; Vernetson, William G; Bolch, W Emmett

    2003-04-01

    Quantifying radiological risk following the inhalation of radioactive aerosols entails not only an assessment of particle deposition within respiratory tract regions but a full accounting of clearance mechanisms whereby particles may be translocated to adjacent respiratory tissue regions, absorbed to blood, or released to the gastrointestinal tract. The model outlined in ICRP Publication 66 represents to date one of the most complete overall descriptions of particle deposition and clearance, as well as localized radiation dosimetry, within the respiratory tract. In this study, a previous review of the ICRP-66 deposition model is extended to the study of the subsequent clearance model. A systematic review of the clearance component within the ICRP 66 respiratory tract model was conducted in which probability density functions were assigned to all input parameters for both 239PuO2 and 238UO2/238U3O8. These distributions were subsequently incorporated within a computer code LUDUC (Lung Dose Uncertainty Code) in which Latin hypercube sampling techniques are used to generate multiple (e.g., 1,000) sets of input vectors (i.e., trials) for all model parameters needed to assess mechanical clearance and particle dissolution/absorption. Integral numbers of nuclear disintegrations, U(s), in various lung regions were shown to be well-described by lognormal probability distributions. Of the four extrathoracic clearance compartments of the respiratory tract, uncertainties in U(s), expressed as the ratio of its 95% to 5% confidence levels, were highest within the LN(ET) tissues for 239PuO2 (ratio of 50 to 130) and within the ET(seq) tissues for 238UO2/238U3O8 (ratio of 12 to 50). Peak uncertainties in U(s) in these respiratory regions occurred at particle sizes of approximately 0.5-0.6 microm where uncertainties in ET2 particle deposition fractions accounted for only approximately 10% of the total U(s) uncertainty for 239PuO2, and only approximately 30% of the total U

  5. The Effects of Grouping and Instructional Strategies on Conceptual Understanding and Critical Thinking Skills in the Secondary Biology Classroom.

    ERIC Educational Resources Information Center

    Duffy, Maryellen; Zeidler, Dana L.

    The purpose of this study was to investigate and describe selected instructional strategies (traditional and constructivist) and grouping practices (homogeneous and heterogeneous) on conceptual understanding and critical thinking skills in biology classrooms in three high schools. The context of the study was the teaching and learning of plant…

  6. Ethnic American Groups in Four Specialized Encyclopedic Works: A Comparative and Critical Analysis.

    ERIC Educational Resources Information Center

    Wertsman, Vladimir F.

    1999-01-01

    Explores the treatment of ethnic groups in the United States in four encyclopedic works: (1) "Harvard Encyclopedia of American Ethnic Groups"; (2) "Gale Encyclopedia of Multicultural America"; (3) "Encyclopedia of New York City"; and (4) "American Immigrant Culture." (SLD)

  7. Ethnic American Groups in Four Specialized Encyclopedic Works: A Comparative and Critical Analysis.

    ERIC Educational Resources Information Center

    Wertsman, Vladimir F.

    1999-01-01

    Explores the treatment of ethnic groups in the United States in four encyclopedic works: (1) "Harvard Encyclopedia of American Ethnic Groups"; (2) "Gale Encyclopedia of Multicultural America"; (3) "Encyclopedia of New York City"; and (4) "American Immigrant Culture." (SLD)

  8. Dose coefficients for ICRP reference pediatric phantoms exposed to idealised external gamma fields.

    PubMed

    Chang, Lienard A; Simon, Steven L; Jorgensen, Timothy J; Schauer, David A; Lee, Choonsik

    2017-03-20

    Organ and effective dose coefficients have been calculated for the International Commission on Radiological Protection (ICRP) reference pediatric phantoms externally exposed to mono-energetic photon radiation (x- and gamma-rays) from 0.01 to 20 MeV. Calculations used Monte Carlo radiation transport techniques. Organ dose coefficients, i.e., organ absorbed dose per unit air kerma (Gy/Gy), were calculated for 28 organs and tissues including the active marrow (or red bone marrow) for 10 phantoms (newborn, 1 year, 5 year, 10 year, and 15 year old male and female). Radiation exposure was simulated for 33 photon mono-energies (0.01-20 MeV) in six irradiation geometries: antero-posterior (AP), postero-anterior, right lateral, left lateral, rotational, and isotropic. Organ dose coefficients for different ages closely agree in AP geometry as illustrated by a small coefficient of variation (COV) (the ratio of the standard deviation to the mean) of 4.4% for the lungs. The small COVs shown for the effective dose and AP irradiation geometry reflect that most of the radiosensitive organs are located in the front part of the human body. In contrast, we observed differences in organ dose coefficients across the ages of the phantoms for lateral irradiation geometries. We also observed variation in dose coefficients across different irradiation geometries, where the COV ranges from 18% (newborn male) to 38% (15 year old male) across idealised whole body irradiation geometries for the major organs (active marrow, colon, lung, stomach wall, and breast) at the energy of 0.1 MeV. Effective dose coefficients were also derived for applicable situations, e.g., radiation protection or risk projection. Our results are the first comprehensive set of organ and effective dose coefficients applicable to children and adolescents based on the newly adopted ICRP pediatric phantom series. Our tabulated organ and effective dose coefficients for these next-generation phantoms should provide more

  9. Deviance of Political Groups and Media Treatment: An Empirical Analysis of a Critical Hypothesis.

    ERIC Educational Resources Information Center

    Shoemaker, Pamela J.

    A study was conducted to test the hypothesis that the mass media act as agents of social control by varying the coverage of political groups in relation to how deviant they perceive the groups to be. Editors from the 100 largest daily newspapers in the United States were asked to rate 11 political groups on four scales thought to measure political…

  10. Building a Society of Solidarity through Critical Pedagogy: Group Teaching as a Social and Democratic Tool

    ERIC Educational Resources Information Center

    Nikolakaki, Maria

    2012-01-01

    Against the menacing shadow of neoliberalism, which promotes individualism and competition, the author illustrates in this paper the need for group teaching. Group teaching as a method of instruction and learning fosters community bonds, solidarity, and is more effective teaching. Group teaching is a democratic tool necessary for society to…

  11. Does Ethnolinguistic Vitality Theory Account for the Actual Vitality of Ethnic Groups? A Critical Evaluation

    ERIC Educational Resources Information Center

    Yagmur, Kutlay

    2011-01-01

    Ethnolinguistic vitality theory asserts that Status, Demographic, Institutional Support and Control factors make up the vitality of ethnolinguistic groups. An assessment of a group's strengths and weaknesses in each of these dimensions provides a rough classification of ethnolinguistic groups into those having low, medium, or high vitality. Low…

  12. Variations in Financial Performance among Peer Groups of Critical Access Hospitals

    ERIC Educational Resources Information Center

    Pink, George H.; Holmes, George M.; Thompson, Roger E.; Slifkin, Rebecca T.

    2007-01-01

    Context: Among the large number of hospitals with critical access hospital (CAH) designation, there is substantial variation in facility revenue as well as the number and types of services provided. If these variations have material effects on financial indicators, then performance comparisons among all CAHs are problematic. Purpose: To…

  13. Staging the Performances of the Privileged Social Group (PSG): Expanding the Philosophical Foundation of Critical Pedagogy

    ERIC Educational Resources Information Center

    Graham, Scott

    2008-01-01

    Contemporary efforts to rethink the philosophical foundation of critical pedagogy are part of the ongoing project to make the field relevant to current struggles against oppression. Inherent to this project is an invitation to account for the plurality of ways and spaces in which privilege is performed in North American society and the troubling…

  14. Developing Deep Group Reflection within a Critical Reflection Action Learning Set

    ERIC Educational Resources Information Center

    Shepherd, Gary

    2016-01-01

    This account of practice describes how a manufacturing company in the North of England transformed their approach to problem-solving and action through the use of a Critical Reflection Action Learning (CRAL) methodology. The company, who had been in business for over 25 years, experienced problems due to a diminishing customer base and substantial…

  15. Strains, Strengths, and Intervention Outcomes: A Critical Examination of Intervention Efficacy for Underrepresented Groups

    ERIC Educational Resources Information Center

    Williams, Krystal L.

    2014-01-01

    This chapter offers a critical lens for examining intervention efficacy. It highlights a conceptual framework particularly relevant for understanding the experiences of underrepresented students and illustrates how such framing can explicate the mechanisms that impede or enhance successful intervention outcomes in STEM fields.

  16. Variations in Financial Performance among Peer Groups of Critical Access Hospitals

    ERIC Educational Resources Information Center

    Pink, George H.; Holmes, George M.; Thompson, Roger E.; Slifkin, Rebecca T.

    2007-01-01

    Context: Among the large number of hospitals with critical access hospital (CAH) designation, there is substantial variation in facility revenue as well as the number and types of services provided. If these variations have material effects on financial indicators, then performance comparisons among all CAHs are problematic. Purpose: To…

  17. Reflection in Action: Using Inquiry Groups to Explore Critical Digital Literacy with Pre-Service Teachers

    ERIC Educational Resources Information Center

    Lohnes Watulak, Sarah

    2016-01-01

    The challenge of preparing teachers and their eventual students to be successful, full participants in today's digital society is one that faces all teacher preparation programs. However, in the United States our current system of technology instruction in pre-service education focuses primarily on functional technology skills, and critical and…

  18. Government, Public Relations, and Lobby Groups: Stimulating Critical Reflections on Information Providers in Society.

    ERIC Educational Resources Information Center

    Dyer, Suzette

    2003-01-01

    In a management class role-playing activity, students adopt the roles of parents, government representatives, and health providers in a scenario about child immunization. The objective is to develop critical understanding of the creation, management, and dissemination of information on decision making. (Contains 26 references.) (SK)

  19. Discussion Group Effectiveness Is Related to Critical Thinking through Interest and Engagement

    ERIC Educational Resources Information Center

    Jones, Janelle M.

    2014-01-01

    Higher student enrolment at North American tertiary institutions over the last decade has led to a greater reliance on lecturing in large classes (i.e., 50 students or more). The efficiency of lecturing as a method of instruction can sometimes come at the cost of student interaction, engagement, critical thinking and satisfaction. Implementing…

  20. Analysis of Critical Thinking Skills in an International, Cross-Institutional Group of Engineering Master's Students

    ERIC Educational Resources Information Center

    Bramhall, Michael D.; Gray, Linda; Corker, Chris; Garnett, Kenisha; Hill, Richard

    2012-01-01

    UK educators often express concerns that students from some cultural backgrounds frequently seem unwilling or are unable to apply critical thinking skills within their academic programmes. This may be due not to a lack of ability or confidence but rather to the way they have been previously taught and assessed. Often, the design of UK courses…

  1. Discussion Group Effectiveness Is Related to Critical Thinking through Interest and Engagement

    ERIC Educational Resources Information Center

    Jones, Janelle M.

    2014-01-01

    Higher student enrolment at North American tertiary institutions over the last decade has led to a greater reliance on lecturing in large classes (i.e., 50 students or more). The efficiency of lecturing as a method of instruction can sometimes come at the cost of student interaction, engagement, critical thinking and satisfaction. Implementing…

  2. Critical Information Literacy beyond the University: Lessons from Service in a Women's Health Interest Group

    ERIC Educational Resources Information Center

    Fountain, Kathleen Carlisle

    2013-01-01

    Library instruction methods most frequently focus on teaching students searching skills to navigate the maze of library databases to locate appropriate research materials. The current theory of critical information literacy instruction calls on librarians to spend more of their time in the classroom focused on understanding the social, political,…

  3. Developing Deep Group Reflection within a Critical Reflection Action Learning Set

    ERIC Educational Resources Information Center

    Shepherd, Gary

    2016-01-01

    This account of practice describes how a manufacturing company in the North of England transformed their approach to problem-solving and action through the use of a Critical Reflection Action Learning (CRAL) methodology. The company, who had been in business for over 25 years, experienced problems due to a diminishing customer base and substantial…

  4. Reflection in Action: Using Inquiry Groups to Explore Critical Digital Literacy with Pre-Service Teachers

    ERIC Educational Resources Information Center

    Lohnes Watulak, Sarah

    2016-01-01

    The challenge of preparing teachers and their eventual students to be successful, full participants in today's digital society is one that faces all teacher preparation programs. However, in the United States our current system of technology instruction in pre-service education focuses primarily on functional technology skills, and critical and…

  5. Critical Information Literacy beyond the University: Lessons from Service in a Women's Health Interest Group

    ERIC Educational Resources Information Center

    Fountain, Kathleen Carlisle

    2013-01-01

    Library instruction methods most frequently focus on teaching students searching skills to navigate the maze of library databases to locate appropriate research materials. The current theory of critical information literacy instruction calls on librarians to spend more of their time in the classroom focused on understanding the social, political,…

  6. Radiation protection recommendations on dose limits: The role of the NCRP and the ICRP and future developments

    SciTech Connect

    Sinclair, W.K.

    1995-02-01

    The purpose of this paper is to review the role of the National Council on Radiation Protection and Measurements (NCRP) and the International Commission on Radiological Protection (ICRP) in making recommendations on dose limits for ionizing radiation exposure for workers and for the public. The text describes the new limits for workers and public recommended by ICRP in 1991 and NCRP in 1993 and the composition of the radiation health detriment on which they are based. The main component of this detriment is the risk of radiation induced cancer which is now estimated to be about three times greater than a decade or so earlier. Uncertainties in these risk estimates are discussed. Some special radiation protection problems, such as those for the embryo or fetus are described. The article also addresses future progress in radiation protection particularly with regard to future improvements in the scientific basis for radiation protection recommendations.

  7. Inclusion of thin target and source regions in alimentary and respiratory tract systems of mesh-type ICRP adult reference phantoms

    NASA Astrophysics Data System (ADS)

    Kim, Han Sung; Yeom, Yeon Soo; Tat Nguyen, Thang; Choi, Chansoo; Han, Min Cheol; Lee, Jai Ki; Kim, Chan Hyeong; Zankl, Maria; Petoussi-Henss, Nina; Bolch, Wesley E.; Lee, Choonsik; Qiu, Rui; Eckerman, Keith; Chung, Beom Sun

    2017-03-01

    It is not feasible to define very small or complex organs and tissues in the current voxel-type adult reference computational phantoms of the International Commission on Radiological Protection (ICRP), which limit dose coefficients for weakly penetrating radiations. To address the problem, the ICRP is converting the voxel-type reference phantoms into mesh-type phantoms. In the present study, as a part of the conversion project, the micrometer-thick target and source regions in the alimentary and respiratory tract systems as described in ICRP Publications 100 and 66 were included in the mesh-type ICRP reference adult male and female phantoms. In addition, realistic lung airway models were simulated to represent the bronchial (BB) and bronchiolar (bb) regions. The electron specific absorbed fraction (SAF) values for the alimentary and respiratory tract systems were then calculated and compared with the values calculated with the stylized models of ICRP Publications 100 and 66. The comparisons show generally good agreement for the oral cavity, oesophagus, and BB, whereas for the stomach, small intestine, large intestine, extrathoracic region, and bb, there are some differences (e.g. up to ~9 times in the large intestine). The difference is mainly due to anatomical difference in these organs between the realistic mesh-type phantoms and the simplified stylized models. The new alimentary and respiratory tract models in the mesh-type ICRP reference phantoms preserve the topology and dimensions of the voxel-type ICRP phantoms and provide more reliable SAF values than the simplified models adopted in previous ICRP Publications.

  8. Inclusion of thin target and source regions in alimentary and respiratory tract systems of mesh-type ICRP adult reference phantoms.

    PubMed

    Kim, Han Sung; Yeom, Yeon Soo; Nguyen, Thang Tat; Choi, Chansoo; Han, Min Cheol; Lee, Jai Ki; Kim, Chan Hyeong; Zankl, Maria; Petoussi-Henss, Nina; Bolch, Wesley E; Lee, Choonsik; Qiu, Rui; Eckerman, Keith; Chung, Beom Sun

    2017-03-21

    It is not feasible to define very small or complex organs and tissues in the current voxel-type adult reference computational phantoms of the International Commission on Radiological Protection (ICRP), which limit dose coefficients for weakly penetrating radiations. To address the problem, the ICRP is converting the voxel-type reference phantoms into mesh-type phantoms. In the present study, as a part of the conversion project, the micrometer-thick target and source regions in the alimentary and respiratory tract systems as described in ICRP Publications 100 and 66 were included in the mesh-type ICRP reference adult male and female phantoms. In addition, realistic lung airway models were simulated to represent the bronchial (BB) and bronchiolar (bb) regions. The electron specific absorbed fraction (SAF) values for the alimentary and respiratory tract systems were then calculated and compared with the values calculated with the stylized models of ICRP Publications 100 and 66. The comparisons show generally good agreement for the oral cavity, oesophagus, and BB, whereas for the stomach, small intestine, large intestine, extrathoracic region, and bb, there are some differences (e.g. up to ~9 times in the large intestine). The difference is mainly due to anatomical difference in these organs between the realistic mesh-type phantoms and the simplified stylized models. The new alimentary and respiratory tract models in the mesh-type ICRP reference phantoms preserve the topology and dimensions of the voxel-type ICRP phantoms and provide more reliable SAF values than the simplified models adopted in previous ICRP Publications.

  9. The Prioritization of Critical Infrastructure for a Pandemic Outbreak in the United States Working Group

    DTIC Science & Technology

    2007-01-16

    potential extreme health impact and containment strategies specific to pandemics. CI/KR owner-operators know the activities and personnel in their...knowledge of the impacts , response strategies, and countermeasures that will be available in a pandemic…1 The Secretaries asked the Council to...needed to improve overall pandemic planning and response, including: identifying cross-sector impacts to specific critical sector operations

  10. Distribution and retention in bone of /sup 226/Ra and comparison with the ICRP 20 model

    SciTech Connect

    Holtzman, R.B.; Rundo, J.; Sha, J.Y.; Spaletto, M.I.

    1981-01-01

    Analyses are presented of the ratios of /sup 226/Ra to calcium in over 650 samples of compact and cancellous bone from 66 female and 26 male subjects who had died from less than one to 60 years after first exposure to radium. The /sup 226/Ra/Ca ratios were normalized to the terminal /sup 226/Ra skeletal content. The /sup 226/Ra/Ca ratios for vertebrae were essentialy identical to those for other cancellous bone for a given subject. Comparisons of the data with predictions of the ICRP model of alkaline earth metabolism show that for female cancellous bone the normalized /sup 226/Ra/Ca ratios tended to be greater than predicted, while those for female cortical bone (femoral and tibial shaft) tended to be less. The data for males were fitted better by the model. A modification of the model to reduce the amount of radium deposited in soft tissue fitted the data better in some respects. A straight line linear least squares fit to the data appeared to fit as well as, or better than, the models. A radiation effect was suggested in that the normalized /sup 226/Ra/Ca ratio for vertebrae relative to the ratio expected increased with skeletal absorbed dose for vertebra. However, no such effect was apparent for compact bone or for the cancellous bone as a whole.

  11. Transfer parameters for ICRP's Reference Animals and Plants in a terrestrial Mediterranean ecosystem.

    PubMed

    Guillén, J; Beresford, N A; Baeza, A; Izquierdo, M; Wood, M D; Salas, A; Muñoz-Serrano, A; Corrales-Vázquez, J M; Muñoz-Muñoz, J G

    2017-09-14

    A system for the radiological protection of the environment (or wildlife) based on Reference Animals and Plants (RAPs) has been suggested by the International Commission on Radiological Protection (ICRP). To assess whole-body activity concentrations for RAPs and the resultant internal dose rates, transfer parameters are required. However, transfer values specifically for the taxonomic families defined for the RAPs are often sparse and furthermore can be extremely site dependent. There is also a considerable geographical bias within available transfer data, with few data for Mediterranean ecosystems. In the present work, stable element concentrations (I, Li, Be, B, Na, Mg, Al, P, S, K. Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Rb, Sr, Mo, Ag, Cd, Cs, Ba, Tl, Pb and U) in terrestrial RAPs, and the corresponding whole-body concentration ratios, CRwo, were determined in two different Mediterranean ecosystems: a Pinewood and a Dehesa (grassland with disperse tree cover). The RAPs considered in the Pinewood ecosystem were Pine Tree and Wild Grass; whereas in the Dehesa ecosystem those considered were Deer, Rat, Earthworm, Bee, Frog, Duck and Wild Grass. The CRwo values estimated from these data are compared to those reported in international compilations and databases. Copyright © 2017. Published by Elsevier Ltd.

  12. Response of Harshaw neutron thermoluminescence dosemeters in terms of the revised ICRP/ICRU recommendations.

    PubMed

    Veinot, K G; Hertel, N E

    2005-01-01

    To monitor workers for external neutron radiation dose, the Y-12 National Security Complex utilises the thermoluminescence dosemeters (TLDs) manufactured by Harshaw. At Y-12, the majority of external dose to workers is due to low-energy photon and/or beta particles emitted from uranium and its progeny. However, some neutron dose is expected since neutrons are produced from (alpha,n) reactions in various compounds found at the plant, including UF4 and UF6. Neutron sources, such as 252Cf, are also used throughout the complex. The Harshaw neutron dosemeter consists of two gamma-sensitive elements (7Li) and two neutron-sensitive elements enriched in 6Li with various shielding/filter materials placed around each of them. In this work, the energy response of the dosemeter to neutrons has been calculated using the Monte Carlo transport code MCNP Version 4-C and, these results are compared with the measured response of the dosemeter to unmoderated and D2O-moderated 252Cf neutrons. The response of the dosemeter has also been determined in terms of the personal absorbed dose and personal dose equivalent as a function of neutron energy based on the recommendations of the ICRP Publication 60 and ICRU Report 49. The energy response of the dosemeter characteristics can be used to generate spectral conversion coefficients for routine neutron absorbed dose and dose equivalent calculations.

  13. Some aspects of the fetal doses given in ICRP Publication 88.

    PubMed

    Phipps, A W; Harrison, J D; Fell, T P; Eckerman, K F; Nosske, D

    2003-01-01

    The International Commission on Radiological Protection (ICRP) has recently published dose coefficients (dose per unit intake, Sv Bq(-1)) for the offspring of women exposed to radionuclides during or before pregnancy. These dose estimates include in utero doses to the embryo and fetus and doses delivered postnatally to the newborn child from radionuclides retained at birth. This paper considers the effect on doses of the time of radionuclide intake and examines the proportion of dose delivered in utero and postnatally for different radionuclides. Methods used to calculate doses to the fetal skeleton are compared. For many radionuclides, doses are greatest for intakes early in pregnancy but important exceptions, for which doses are greatest for intakes later in pregnancy, are iodine isotopes and isotopes of the alkaline earth elements, including strontium. While radionuclides such as 131I deliver dose largely in utero, even for intakes late in pregnancy, others such as 239Pu deliver dose largely postnatally, even for intakes early during pregnancy. For alpha emitters deposited in the skeleton, the assumption made is of uniform distribution of the radionuclide and of target cells for leukaemia and bone cancer in utero; that is, the developing bone structure is not considered. However, for beta emitters, the bone structure was considered. Both approaches can be regarded as reasonably conservative, given uncertainties in particular in the location of the target cells and the rapid growth and remodelling of the skeleton at this stage of development.

  14. Dosimetric Significance of the ICRP's Updated Guidance and Models, 1989-2003, and Implications for U.S. Federal Guidance

    SciTech Connect

    Leggett, R.W.

    2003-09-10

    Over the past two decades the U.S. Environmental Protection Agency (EPA) has issued a series of Federal guidance documents for the purpose of providing the Federal and State agencies with technical information to assist their implementation of radiation protection programs. Currently recommended dose conversion factors, annual limits on intake, and derived air concentrations for intake of radionuclides are tabulated in Federal Guidance Report No. 11 (FGR 11), published in 1988. The tabulations in FGR 11 were based on dosimetric quantities and biokinetic and dosimetric models of the International Commission on Radiological Protection (ICRP) developed for application to occupational exposures. Since the publication of FGR 11 the ICRP has revised some of its dosimetric quantities and its models for workers and has also developed age-specific models and dose conversion factors for intake of radionuclides by members of the public. This report examines the extent of the changes in the inhalation and ingestion dose coefficients of FGR 11 implied by the updated recommendations of the ICRP, both for workers and members of the public.

  15. Organ dose conversion coefficients on an ICRP-based Chinese adult male voxel model from idealized external photons exposures.

    PubMed

    Liu, Liye; Zeng, Zhi; Li, Junli; Qiu, Rui; Zhang, Binquan; Ma, Jizeng; Li, Ren; Li, Wenqian; Bi, Lei

    2009-11-07

    A high-resolution whole-body voxel model called CAM representing the Chinese adult male was constructed in this paper based on a previous individual voxel model. There are more than 80 tissues and organs in CAM, including almost all organs required in the ICRP new recommendation. The mass of individual organs has been adjusted to the Chinese reference data. Special considerations were given to representing the gross spatial distribution of various bone constituents as realistically as possible during the construction of the site-specific skeleton. Organ dose conversion coefficients were calculated for six idealized external photon exposures from 10 keV to 10 MeV by using Monte Carlo simulation. The resulting dose coefficients were then compared with those from other models, e.g. CMP, ICRP 74, Rex, HDRK-man and VIP-man. Old and new effective male doses of CAM were calculated by using the tissue weighting factors from ICRP 60 and 103 Publications, respectively. Dosimetric differences between mathematical and voxel models, and the differences between Asian and Caucasian models are also discussed in this paper.

  16. 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.

  17. Monte Carlo tests of renormalization-group predictions for critical phenomena in Ising models

    NASA Astrophysics Data System (ADS)

    Binder, Kurt; Luijten, Erik

    2001-04-01

    A critical review is given of status and perspectives of Monte Carlo simulations that address bulk and interfacial phase transitions of ferromagnetic Ising models. First, some basic methodological aspects of these simulations are briefly summarized (single-spin flip vs. cluster algorithms, finite-size scaling concepts), and then the application of these techniques to the nearest-neighbor Ising model in d=3 and 5 dimensions is described, and a detailed comparison to theoretical predictions is made. In addition, the case of Ising models with a large but finite range of interaction and the crossover scaling from mean-field behavior to the Ising universality class are treated. If one considers instead a long-range interaction described by a power-law decay, new classes of critical behavior depending on the exponent of this power law become accessible, and a stringent test of the ε-expansion becomes possible. As a final type of crossover from mean-field type behavior to two-dimensional Ising behavior, the interface localization-delocalization transition of Ising films confined between “competing” walls is considered. This problem is still hampered by questions regarding the appropriate coarse-grained model for the fluctuating interface near a wall, which is the starting point for both this problem and the theory of critical wetting.

  18. Studies of genotoxicity and mutagenicity of nitroimidazoles: demystifying this critical relationship with the nitro group

    PubMed Central

    Boechat, Núbia; Carvalho, Alcione S; Salomão, Kelly; de Castro, Solange L; Araujo-Lima, Carlos F; Mello, Francisco VC; Felzenszwalb, Israel; Aiub, Claudia AF; Conde, Taline Ramos; Zamith, Helena PS; Skupin, Rolf; Haufe, Günter

    2015-01-01

    Nitroimidazoles exhibit high microbicidal activity, but mutagenic, genotoxic and cytotoxic properties have been attributed to the presence of the nitro group. However, we synthesised nitroimidazoles with activity against the trypomastigotes of Trypanosoma cruzi, but that were not genotoxic. Herein, nitroimidazoles (11-19) bearing different substituent groups were investigated for their potential induction of genotoxicity (comet assay) and mutagenicity (Salmonella/Microsome assay) and the correlations of these effects with their trypanocidal effect and with megazol were investigated. The compounds were designed to analyse the role played by the position of the nitro group in the imidazole nucleus (C-4 or C-5) and the presence of oxidisable groups at N-1 as an anion receptor group and the role of a methyl group at C-2. Nitroimidazoles bearing NO2 at C-4 and CH3 at C-2 were not genotoxic compared to those bearing NO2 at C-5. However, when there was a CH3 at C-2, the position of the NO2 group had no influence on the genotoxic activity. Fluorinated compounds exhibited higher genotoxicity regardless of the presence of CH3 at C-2 or NO2 at C-4 or C-5. However, in compounds 11 (2-CH3; 4-NO2; N-CH2OHCH2Cl) and 12 (2-CH3; 4-NO2; N-CH2OHCH2F), the fluorine atom had no influence on genotoxicity. This study contributes to the future search for new and safer prototypes and provide. PMID:26018452

  19. A critical appraisal of existing concepts for the grouping of nanomaterials.

    PubMed

    Arts, Josje H E; Hadi, Mackenzie; Keene, Athena M; Kreiling, Reinhard; Lyon, Delina; Maier, Monika; Michel, Karin; Petry, Thomas; Sauer, Ursula G; Warheit, David; Wiench, Karin; Landsiedel, Robert

    2014-11-01

    The grouping of substances serves to streamline testing for regulatory purposes. General grouping approaches for chemicals have been implemented in, e.g., the EU chemicals regulation. While specific regulatory frameworks for the grouping of nanomaterials are unavailable, this topic is addressed in different publications, and preliminary guidance is provided in the context of substance-related legislation or the occupational setting. The European Centre for Ecotoxicology and Toxicology of Chemicals Task Force on the Grouping of Nanomaterials reviewed available concepts for the grouping of nanomaterials for human health risk assessment. In their broad conceptual design, the evaluated approaches are consistent or complement each other. All go beyond the determination of mere structure-activity relationships and are founded on different aspects of the nanomaterial life cycle. These include the NM's material properties and biophysical interactions, specific types of use and exposure, uptake and kinetics, and possible early and apical biological effects. None of the evaluated grouping concepts fully take into account all of these aspects. Subsequent work of the Task Force will aim at combining the available concepts into a comprehensive 'multiple perspective' framework for the grouping of nanomaterials that will address all of the mentioned aspects of their life cycles.

  20. Studies of genotoxicity and mutagenicity of nitroimidazoles: demystifying this critical relationship with the nitro group.

    PubMed

    Boechat, Núbia; Carvalho, Alcione S; Salomão, Kelly; Castro, Solange L de; Araujo-Lima, Carlos F; Mello, Francisco V C; Felzenszwalb, Israel; Aiub, Claudia A F; Conde, Taline Ramos; Zamith, Helena P S; Skupin, Rolf; Haufe, Günter

    2015-06-01

    Nitroimidazoles exhibit high microbicidal activity, but mutagenic, genotoxic and cytotoxic properties have been attributed to the presence of the nitro group. However, we synthesised nitroimidazoles with activity against the trypomastigotes of Trypanosoma cruzi, but that were not genotoxic. Herein, nitroimidazoles (11-19) bearing different substituent groups were investigated for their potential induction of genotoxicity (comet assay) and mutagenicity (Salmonella/Microsome assay) and the correlations of these effects with their trypanocidal effect and with megazol were investigated. The compounds were designed to analyse the role played by the position of the nitro group in the imidazole nucleus (C-4 or C-5) and the presence of oxidisable groups at N-1 as an anion receptor group and the role of a methyl group at C-2. Nitroimidazoles bearing NO2 at C-4 and CH3 at C-2 were not genotoxic compared to those bearing NO 2 at C-5. However, when there was a CH3 at C-2, the position of the NO2 group had no influence on the genotoxic activity. Fluorinated compounds exhibited higher genotoxicity regardless of the presence of CH3 at C-2 or NO2 at C-4 or C-5. However, in compounds 11 (2-CH3; 4-NO2; N-CH2OHCH2Cl) and 12 (2-CH3; 4-NO2; N-CH2OHCH2F), the fluorine atom had no influence on genotoxicity. This study contributes to the future search for new and safer prototypes and provide.

  1. Comparison Groups in Yoga Research: A Systematic Review and Critical Evaluation of the Literature

    PubMed Central

    Groessl, Erik; Maiya, Meghan; Sarkin, Andrew; Eisen, Susan V.; Riley, Kristen; Elwy, A. Rani

    2014-01-01

    Objectives Comparison groups are essential for accurate testing and interpretation of yoga intervention trials. However, selecting proper comparison groups is difficult because yoga comprises a very heterogeneous set of practices and its mechanisms of effect have not been conclusively established. Methods We conducted a systematic review of the control and comparison groups used in published randomized controlled trials (RCTs) of yoga. Results We located 128 RCTs that met our inclusion criteria; of these, 65 included only a passive control and 63 included at least one active comparison group. Primary comparison groups were physical exercise (43%), relaxation/meditation (20%), and education (16%). Studies rarely provided a strong rationale for choice of comparison. Considering year of publication, the use of active controls in yoga research appears to be slowly increasing over time. Conclusions Given that yoga has been established as a potentially powerful intervention, future research should use active control groups. Further, care is needed to select comparison conditions that help to isolate the specific mechanisms of yoga’s effects. PMID:25440384

  2. Peer group reflection helps clinical teachers to critically reflect on their teaching.

    PubMed

    Boerboom, Tobias B B; Jaarsma, Debbie; Dolmans, Diana H J M; Scherpbier, Albert J J A; Mastenbroek, Nicole J J M; Van Beukelen, Peter

    2011-01-01

    Student evaluations can help clinical teachers to reflect on their teaching skills and find ways to improve their teaching. Studies have shown that the mere presentation of student evaluations is not a sufficient incentive for teachers to critically reflect on their teaching. We evaluated and compared the effectiveness of two feedback facilitation strategies that were identical except for a peer reflection meeting. In this study, 54 clinical teachers were randomly assigned to two feedback strategies. In one strategy, a peer reflection was added as an additional step. All teachers completed a questionnaire evaluating the strategy that they had experienced. We analysed the reflection reports and the evaluation questionnaire. Both strategies stimulated teachers to reflect on feedback and formulate alternative actions for their teaching practice. The teachers who had participated in the peer reflection meeting showed deeper critical reflection and more concrete plans to change their teaching. All feedback strategies were considered effective by the majority of the teachers. Strategies with student feedback and self-assessment stimulated reflection on teaching and helped clinical teachers to formulate plans for improvement. A peer reflection meeting seemed to enhance reflection quality. Further research should establish whether it can have lasting effects on teaching quality.

  3. The Interagency Software Evaluation Group: A Critical Evaluation of the ADINA, NASTRAN, and STAGS Structural Mechanics Computer Programs.

    DTIC Science & Technology

    1981-12-01

    the report goes on to describe the macro programming language of NASTRAN , called DMAP (Direct Matrix Abstraction Program), which enables the skilled...S. TYPE Of REPORT a PERIOD COVERED The Interagency Software Evaluation Group: A Critical Evaluation of the ADINA, Technc Report No. 2 NASTRAN , and...consisting of the evaluation of the codes ADINA, NASTRAN , and STAGS. The evaluation criteria are discussed in some detail. DD FORM 17 IT|N O -I4NOV

  4. The ABO Histo-Blood Group and AKI in Critically Ill Patients with Trauma or Sepsis.

    PubMed

    Reilly, John P; Anderson, Brian J; Mangalmurti, Nilam S; Nguyen, Tam D; Holena, Daniel N; Wu, Qufei; Nguyen, Ethan T; Reilly, Muredach P; Lanken, Paul N; Christie, Jason D; Meyer, Nuala J; Shashaty, Michael G S

    2015-11-06

    ABO blood types are determined by antigen modifications on glycoproteins and glycolipids and associated with altered plasma levels of inflammatory and endothelial injury markers implicated in AKI pathogenesis. We sought to determine the association of ABO blood types with AKI risk in critically ill patients with trauma or sepsis. We conducted two prospective cohort studies at an urban, academic, level I trauma center and tertiary referral center; 497 patients with trauma admitted to the surgical intensive care unit between 2005 and 2010 with an injury severity score >15 and 759 patients with severe sepsis admitted to the medical intensive care unit between 2008 and 2013 were followed for 6 days for the development of incident AKI. AKI was defined by Acute Kidney Injury Network creatinine and dialysis criteria. Of 497 patients with trauma, 134 developed AKI (27%). In multivariable analysis, blood type A was associated with higher AKI risk relative to type O among patients of European descent (n=229; adjusted risk, 0.28 versus 0.14; risk difference, 0.14; 95% confidence interval, 0.03 to 0.24; P=0.02). Of 759 patients with sepsis, AKI developed in 326 (43%). Blood type A again conferred higher AKI risk relative to type O among patients of European descent (n=437; adjusted risk, 0.53 versus 0.40; risk difference, 0.14; 95% confidence interval, 0.04 to 0.23; P=0.01). Findings were similar when analysis was restricted to those patients who did not develop acute respiratory distress syndrome or were not transfused. We did not detect a significant association between blood type and AKI risk among individuals of African descent in either cohort. Blood type A is independently associated with AKI risk in critically ill patients with trauma or severe sepsis of European descent, suggesting a role for ABO glycans in AKI susceptibility. Copyright © 2015 by the American Society of Nephrology.

  5. The ABO Histo-Blood Group and AKI in Critically Ill Patients with Trauma or Sepsis

    PubMed Central

    Anderson, Brian J.; Mangalmurti, Nilam S.; Nguyen, Tam D.; Holena, Daniel N.; Wu, Qufei; Nguyen, Ethan T.; Reilly, Muredach P.; Lanken, Paul N.; Christie, Jason D.; Meyer, Nuala J.; Shashaty, Michael G.S.

    2015-01-01

    Background and objective ABO blood types are determined by antigen modifications on glycoproteins and glycolipids and associated with altered plasma levels of inflammatory and endothelial injury markers implicated in AKI pathogenesis. We sought to determine the association of ABO blood types with AKI risk in critically ill patients with trauma or sepsis. Design, setting, participants, & measurements We conducted two prospective cohort studies at an urban, academic, level I trauma center and tertiary referral center; 497 patients with trauma admitted to the surgical intensive care unit between 2005 and 2010 with an injury severity score >15 and 759 patients with severe sepsis admitted to the medical intensive care unit between 2008 and 2013 were followed for 6 days for the development of incident AKI. AKI was defined by Acute Kidney Injury Network creatinine and dialysis criteria. Results Of 497 patients with trauma, 134 developed AKI (27%). In multivariable analysis, blood type A was associated with higher AKI risk relative to type O among patients of European descent (n=229; adjusted risk, 0.28 versus 0.14; risk difference, 0.14; 95% confidence interval, 0.03 to 0.24; P=0.02). Of 759 patients with sepsis, AKI developed in 326 (43%). Blood type A again conferred higher AKI risk relative to type O among patients of European descent (n=437; adjusted risk, 0.53 versus 0.40; risk difference, 0.14; 95% confidence interval, 0.04 to 0.23; P=0.01). Findings were similar when analysis was restricted to those patients who did not develop acute respiratory distress syndrome or were not transfused. We did not detect a significant association between blood type and AKI risk among individuals of African descent in either cohort. Conclusions Blood type A is independently associated with AKI risk in critically ill patients with trauma or severe sepsis of European descent, suggesting a role for ABO glycans in AKI susceptibility. PMID:26342043

  6. Tagging Thinking Types in Asynchronous Discussion Groups: Effects on Critical Thinking

    ERIC Educational Resources Information Center

    Schellens, T.; Van Keer, H.; De Wever, B.; Valcke, M.

    2009-01-01

    The present study focuses on the use of thinking types as a possible way to structure university students' discourse in asynchronous discussion groups and consequently promote their learning. More specifically, the aim of the study is to determine how requiring students to label their contributions by means of De Bono's (1991) thinking hats…

  7. Does Project L.I.V.E. Case Modality Impact Critical Thinking in PBL Groups?

    ERIC Educational Resources Information Center

    Kamin, Carol; O'Sullivan, Patricia; Deterding, Robin

    Problem-based learning (PBL) with simulated cases is one method of delivering standardized pediatric curricular objectives, but the fact that students are dispersed and participating in community-based practices makes group meetings difficult. To address these issues, researchers developed and tested a new modality for presenting PBL cases, a…

  8. WORKSHOP TO IDENTIFY CRITICAL WINDOWS OF EXPOSURE FOR CHILDREN'S HEALTH: CARDIOVASCULAR AND ENDOCRINE WORK GROUP SUMMARY

    EPA Science Inventory

    The work group on cardiovascular and endocrine effects was asked to review the current state of knowledge about children's windows of vulnerability to developmental toxicants and to recommend how that information may be used to improve risk assessment and public health. We consi...

  9. Creating Spaces for Critical Transformative Dialogues: Legitimising Discussion Groups as Professional Practice

    ERIC Educational Resources Information Center

    Edwards-Groves, Christine J.

    2013-01-01

    Focussed dialogue (as lived and living practices) can have a powerful role in renewing professional practice, advancing its sustainability and development as administrative and political systems colonise the practices of teachers and teacher educators. However, participating in discussion groups for many teachers, including those in academia, is…

  10. A Framework for Conducting Critical Dialectical Pluralist Focus Group Discussions Using Mixed Research Techniques

    ERIC Educational Resources Information Center

    Onwuegbuzie, Anthony J.; Frels, Rebecca K.

    2015-01-01

    Although focus group discussions (FGDs) represent a popular data collection tool for researchers, they contain an extremely serious flaw: FGD researchers have ultimate power over all decisions made at every stage of the research process--from the conceptualization of the research, to the planning of the research study, to the implementation of the…

  11. Training Battalion Command Groups in Simulated Combat: Identification and Measurement of Critical Performances

    DTIC Science & Technology

    1979-06-01

    criti- cal command group performance requirements. These special requiremientU are expressed in Human Recources Need 78-147, Development of Improved...FAA-NAFEC, Atlantic City, ATTN: Human Engr Br 1 HO, USMC, Commandant, ATTN- Code MPI.-20 28 I FAA Aeronautical Cit. Oklahoma City, ATTN, AAC-44D 2

  12. Beginning Teachers' Study Groups: A Place to Continue Critical Conversations about Teaching Writing

    ERIC Educational Resources Information Center

    Masuda, Avis; Ebersole, Michele

    2012-01-01

    This article describes how a study group for beginning teachers, led by instructors from the teacher education program from which they had just graduated, supported the novice teachers' abilities to survive their induction year and the constraints of school practices influenced by high-stakes accountability policies. Findings demonstrate that the…

  13. Critical behaviour of a fluid in a random shear flow: renormalization group analysis of a simplified model

    NASA Astrophysics Data System (ADS)

    Antonov, N. V.; Ignatieva, A. A.

    2006-11-01

    Critical behaviour of a fluid (binary mixture or liquid crystal), subjected to strongly anisotropic turbulent mixing, is studied by means of the field theoretic renormalization group. As a simplified model, relaxational stochastic dynamics of a non-conserved scalar order parameter, coupled to a random velocity field with prescribed statistics, is considered. The velocity is taken Gaussian, white in time, with a correlation function of the form ~δ(t - t')/|kbottom|d+ξ, where kbottom is the component of the wave vector, perpendicular to the distinguished direction ('direction of the flow')—the d-dimensional generalization of the ensemble introduced by Avellaneda and Majda (1990 Commun. Math. Phys. 131 381) within the context of passive scalar advection. It is shown that, depending on the relation between the exponent ξ and the space dimensionality d, the system exhibits various types of large-scale self-similar behaviour, associated with different infrared attractive fixed points of the renormalization group equations. In addition to well-known asymptotic regimes (model A of equilibrium critical dynamics and a passively advected scalar with no self-interaction), the existence of a new, non-equilibrium and strongly anisotropic type of critical behaviour (universality class) is established, and the corresponding critical dimensions are calculated to the second order of the double expansion in ξ and ɛ = 4 - d (two-loop approximation). The most realistic values of the model parameters (for example, d = 3 and the Kolmogorov exponent ξ = 4/3) belong to this class. The scaling behaviour appears anisotropic in the sense that the critical dimensions related to the directions parallel and perpendicular to the flow are essentially different. The results are in qualitative agreement with the results, obtained in experiments and simulations of fluid systems subjected to various kinds of regular and chaotic anisotropic flows.

  14. Identifying critical nutrient intake in groups at risk of poverty in Europe: the CHANCE project approach.

    PubMed

    Nikolić, Marina; Glibetić, Maria; Gurinović, Mirjana; Milešević, Jelena; Khokhar, Santosh; Chillo, Stefania; Abaravicius, Jonas Algis; Bordoni, Alessandra; Capozzi, Francesco

    2014-04-02

    The aim of the CHANCE project is to develop novel and affordable nutritious foods to optimize the diet and reduce the risk of diet-related diseases among groups at risk of poverty (ROP). This paper describes the methodology used in the two initial steps to accomplish the project's objective as follows: 1. a literature review of existing data and 2. an identification of ROP groups with which to design and perform the CHANCE nutritional survey, which will supply new data that is useful for formulating the new CHANCE food. Based on the literature review, a low intake of fruit and vegetables, whole grain products, fish, energy, fiber, vitamins B1, B2, B3, B6, B12 and C, folate, calcium, magnesium, iron, potassium and zinc and a high intake of starchy foods, processed meat and sodium were apparent. However, the available data appeared fragmented because of the different methodologies used in the studies. A more global vision of the main nutritional problems that are present among low-income people in Europe is needed, and the first step to achieve this goal is the use of common criteria to define the risk of poverty. The scoring system described here represents novel criteria for defining at-risk-of-poverty groups not only in the CHANCE-participating countries but also all over Europe.

  15. Identifying Critical Nutrient Intake in Groups at Risk of Poverty in Europe: The CHANCE Project Approach

    PubMed Central

    Nikolić, Marina; Glibetić, Maria; Gurinović, Mirjana; Milešević, Jelena; Khokhar, Santosh; Chillo, Stefania; Abaravicius, Jonas Algis; Bordoni, Alessandra; Capozzi, Francesco

    2014-01-01

    The aim of the CHANCE project is to develop novel and affordable nutritious foods to optimize the diet and reduce the risk of diet-related diseases among groups at risk of poverty (ROP). This paper describes the methodology used in the two initial steps to accomplish the project’s objective as follows: 1. a literature review of existing data and 2. an identification of ROP groups with which to design and perform the CHANCE nutritional survey, which will supply new data that is useful for formulating the new CHANCE food. Based on the literature review, a low intake of fruit and vegetables, whole grain products, fish, energy, fiber, vitamins B1, B2, B3, B6, B12 and C, folate, calcium, magnesium, iron, potassium and zinc and a high intake of starchy foods, processed meat and sodium were apparent. However, the available data appeared fragmented because of the different methodologies used in the studies. A more global vision of the main nutritional problems that are present among low-income people in Europe is needed, and the first step to achieve this goal is the use of common criteria to define the risk of poverty. The scoring system described here represents novel criteria for defining at-risk-of-poverty groups not only in the CHANCE-participating countries but also all over Europe. PMID:24699195

  16. HUMTRN: documentation and verification for an ICRP-based age- and sex-specific human simulation model for radionuclide dose assessment

    SciTech Connect

    Gallegos, A.F.; Wenzel, W.J.

    1984-06-01

    The dynamic human simulation model HUMTRN is designed specifically as a major module of BIOTRAN to integrate climatic, hydrologic, atmospheric, food crop, and herbivore simulation with human dietary and physiological characteristics, and metabolism and radionuclides to predict radiation doses to selected organs of both sexes in different age groups. The model is based on age- and weight-specific equations developed for predicting human radionuclide transport from metabolic and physical characteristics. These characteristics are modeled from studies documented by the International Commission on Radiological Protection (ICRP 23). HUMTRN allows cumulative doses from uranium or plutonium radionuclides to be predicted by modeling age-specific anatomical, physiological, and metabolic properties of individuals between 1 and 70 years of age and can track radiation exposure and radionuclide metabolism for any age group for specified daily or yearly time periods. The simulated daily dose integration of eight or more simultaneous air, water, and food intakes gives a new, comprehensive, dynamic picture of radionuclide intake, uptake, and hazard analysis for complex scenarios. A detailed example using site-specific data based on the Pantex studies is included for verification. 14 references, 24 figures, 10 tables.

  17. Absence of renormalization group pathologies near the critical temperature. Two examples

    NASA Astrophysics Data System (ADS)

    Haller, Karl; Kennedy, Tom

    1996-12-01

    We consider real-space renormalization group transformations for Ising-type systems which are formally defined by exp [ { - H'(σ ')} ] = sumlimits_σ {T(σ ,σ ')} exp [ { - H(σ )} ] where T(σ, σ') is a probability kernel, i.e., ∑σ' T(σ,σ') = 1 for every configuration σ. For each choice of the block spin configuration σ', let σ', let μσ' be the measure on spin configurations σ which is formally given by taking the probability of σ to be proportional to T(σ, σ') exp[- H(σ)]. We give a condition which is sufficient to imply that the renormalized Hamiltonian H' is defined. Roughly speaking, the condition is that the collection of measures μσ' is in the high-temperature phase uniformly in the block spin configuration σ'. The proof of this result uses methods of Olivieri and Picco. We use our theorem to prove that the first iteration of the renormalization group transformation is defined in the following two examples: decimation with spacing b = 2 on the square lattice with β < 1.36β c and the Kadanoff transformation with parameter p on the trian gular lattice in a subset of the β, p plane that includes values of β greater than β c .

  18. OECD/NEA expert group on uncertainty analysis for criticality safety assessment: Results of benchmark on sensitivity calculation (phase III)

    SciTech Connect

    Ivanova, T.; Laville, C.; Dyrda, J.; Mennerdahl, D.; Golovko, Y.; Raskach, K.; Tsiboulia, A.; Lee, G. S.; Woo, S. W.; Bidaud, A.; Sabouri, P.; Bledsoe, K.; Rearden, B.; Gulliford, J.; Michel-Sendis, F.

    2012-07-01

    The sensitivities of the k{sub eff} eigenvalue to neutron cross sections have become commonly used in similarity studies and as part of the validation algorithm for criticality safety assessments. To test calculations of the sensitivity coefficients, a benchmark study (Phase III) has been established by the OECD-NEA/WPNCS/EG UACSA (Expert Group on Uncertainty Analysis for Criticality Safety Assessment). This paper presents some sensitivity results generated by the benchmark participants using various computational tools based upon different computational methods: SCALE/TSUNAMI-3D and -1D, MONK, APOLLO2-MORET 5, DRAGON-SUSD3D and MMKKENO. The study demonstrates the performance of the tools. It also illustrates how model simplifications impact the sensitivity results and demonstrates the importance of 'implicit' (self-shielding) sensitivities. This work has been a useful step towards verification of the existing and developed sensitivity analysis methods. (authors)

  19. Assessment of the Absorbed Dose in the Kidney of Nuclear Nephrology Paediatric Patients using ICRP Biokinetic Data and Monte Carlo Simulations with Mass-Scaled Paediatric Voxel Phantoms.

    PubMed

    Teles, P; Mendes, M; Zankl, M; de Sousa, V; Santos, A I; Vaz, P

    2016-04-21

    The aim of this work is to use Monte Carlo simulations and VOXEL phantoms to estimate the absorbed dose in paediatric patients (aged from 2 weeks to 16 y), with normal renal function, to whom technetium-99m-dimercaptosuccinic acid ((99m)Tc-DMSA) was administered, for diagnostic renal scintigraphy purposes; and compare them with values obtained using the International Commission on Radiological Protection (ICRP) methodology. In the ICRP methodology, the cumulated absorbed dose in the kidneys is estimated by multiplying the administered activity with the corresponding given dose coefficients. The other methods were based on Monte Carlo simulations performed on two paediatric voxel phantoms ( ITALIC! CHILDand ITALIC! BABY), and another three phantoms, which were modified to suit the mass of the patients' kidneys, and other anatomical factors. Different ITALIC! S-values were estimated using this methodology, which together with solving the ICRP biokinetic model to determine the cumulated activities, allowed for the estimation of absorbed doses different from those obtained with the ICRP method, together with new dose coefficients. The obtained values were then compared. The deviations suggest that the ITALIC! S-values are strongly dependent on the patient's total body weight, which could be in contrast with the ICRP data, which is provided by age, regardless of other anatomical parameters.

  20. Manganese Homeostasis in Group A Streptococcus Is Critical for Resistance to Oxidative Stress and Virulence

    PubMed Central

    Turner, Andrew G.; Ong, Cheryl-lynn Y.; Gillen, Christine M.; Davies, Mark R.; West, Nicholas P.; McEwan, Alastair G.

    2015-01-01

    ABSTRACT Streptococcus pyogenes (group A Streptococcus [GAS]) is an obligate human pathogen responsible for a spectrum of human disease states. Metallobiology of human pathogens is revealing the fundamental role of metals in both nutritional immunity leading to pathogen starvation and metal poisoning of pathogens by innate immune cells. Spy0980 (MntE) is a paralog of the GAS zinc efflux pump CzcD. Through use of an isogenic mntE deletion mutant in the GAS serotype M1T1 strain 5448, we have elucidated that MntE is a manganese-specific efflux pump required for GAS virulence. The 5448ΔmntE mutant had significantly lower survival following infection of human neutrophils than did the 5448 wild type and the complemented mutant (5448ΔmntE::mntE). Manganese homeostasis may provide protection against oxidative stress, explaining the observed ex vivo reduction in virulence. In the presence of manganese and hydrogen peroxide, 5448ΔmntE mutant exhibits significantly lower survival than wild-type 5448 and the complemented mutant. We hypothesize that MntE, by maintaining homeostatic control of cytoplasmic manganese, ensures that the peroxide response repressor PerR is optimally poised to respond to hydrogen peroxide stress. Creation of a 5448ΔmntE-ΔperR double mutant rescued the oxidative stress resistance of the double mutant to wild-type levels in the presence of manganese and hydrogen peroxide. This work elucidates the mechanism for manganese toxicity within GAS and the crucial role of manganese homeostasis in maintaining GAS virulence. PMID:25805729

  1. Breakthrough pain and its treatment: critical review and recommendations of IOPS (Italian Oncologic Pain Survey) expert group.

    PubMed

    Mercadante, Sebastiano; Marchetti, Paolo; Cuomo, Arturo; Mammucari, Massimo; Caraceni, Augusto

    2016-02-01

    Controversies exist about the definition and epidemiology of breakthrough cancer pain (BTcP), the pharmacological treatment options, drug dosing, and how to select the medications for BTcP among the new fentanyl products. Existing data were critically evaluated to provide recommendations by an expert group. An algorithm to diagnose BTcP should be used followed by a careful assessment. Fentanyl products provide efficacy and rapidity of action to counteract the temporal pattern of BTcP. The doses of opioids used for background pain should guide the choice of the doses of fentanyl products. The choice of fentanyl products should be based on individual clinical conditions.

  2. Validation of nuclear criticality safety software and 27 energy group ENDF/B-IV cross sections. Revision 1

    SciTech Connect

    Lee, B.L. Jr.; D`Aquila, D.M.

    1996-01-01

    The original validation report, POEF-T-3636, was documented in August 1994. The document was based on calculations that were executed during June through August 1992. The statistical analyses in Appendix C and Appendix D were completed in October 1993. This revision is written to clarify the margin of safety being used at Portsmouth for nuclear criticality safety calculations. This validation gives Portsmouth NCS personnel a basis for performing computerized KENO V.a calculations using the Lockheed Martin Nuclear Criticality Safety Software. The first portion of the document outlines basic information in regard to validation of NCSS using ENDF/B-IV 27-group cross sections on the IBM3090 at ORNL. A basic discussion of the NCSS system is provided, some discussion on the validation database and validation in general. Then follows a detailed description of the statistical analysis which was applied. The results of this validation indicate that the NCSS software may be used with confidence for criticality calculations at the Portsmouth Gaseous Diffusion Plant. For calculations of Portsmouth systems using the specified codes and systems covered by this validation, a maximum k{sub eff} including 2{sigma} of 0.9605 or lower shall be considered as subcritical to ensure a calculational margin of safety of 0.02. The validation of NCSS on the IBM 3090 at ORNL was extended to include NCSS on the IBM 3090 at K-25.

  3. High Mobility Group Box-1 Protein and Outcomes in Critically Ill Surgical Patients Requiring Open Abdominal Management

    PubMed Central

    Malig, Michelle S.; Jenne, Craig N.; Ball, Chad G.; Roberts, Derek J.; Xiao, Zhengwen

    2017-01-01

    Background. Previous studies assessing various cytokines in the critically ill/injured have been uninformative in terms of translating to clinical care management. Animal abdominal sepsis work suggests that enhanced intraperitoneal (IP) clearance of Damage-Associated Molecular Patterns (DAMPs) improves outcome. Thus measuring the responses of DAMPs offers alternate potential insights and a representative DAMP, High Mobility Group Box-1 protein (HMGB-1), was considered. While IP biomediators are being recognized in critical illness/trauma, HMGB-1 behaviour has not been examined in open abdomen (OA) management. Methods. A modified protocol for HMGB-1 detection was used to examine plasma/IP fluid samples from 44 critically ill/injured OA patients enrolled in a randomized controlled trial comparing two negative pressure peritoneal therapies (NPPT): Active NPPT (ANPPT) and Barker's Vacuum Pack NPPT (BVP). Samples were collected and analyzed at the time of laparotomy and at 24 and 48 hours after. Results. There were no statistically significant differences in survivor versus nonsurvivor HMGB-1 plasma or IP concentrations at baseline, 24 hours, or 48 hours. However, plasma HMGB-1 levels tended to increase continuously in the BVP cohort. Conclusions. HMGB-1 appeared to behave differently between NPPT cohorts. Further studies are needed to elucidate the relationship of HMGB-1 and outcomes in septic/injured patients. PMID:28286376

  4. Effects of Random Environment on a Self-Organized Critical System: Renormalization Group Analysis of a Continuous Model

    NASA Astrophysics Data System (ADS)

    Antonov, N. V.; Kakin, P. I.

    2016-02-01

    We study effects of the random fluid motion on a system in a self-organized critical state. The latter is described by the continuous stochastic model proposed by Hwa and Kardar [Phys. Rev. Lett. 62: 1813 (1989)]. The advecting velocity field is Gaussian, not correlated in time, with the pair correlation function of the form ∝ δ(t - t')/k⊥d-1+ξ , where k⊥ = |k⊥| and k⊥ is the component of the wave vector, perpendicular to a certain preferred direction - the d-dimensional generalization of the ensemble introduced by Avellaneda and Majda [Commun. Math. Phys. 131: 381 (1990)]. Using the field theoretic renormalization group we show that, depending on the relation between the exponent ξ and the spatial dimension d, the system reveals different types of large-scale, long-time scaling behaviour, associated with the three possible fixed points of the renormalization group equations. They correspond to ordinary diffusion, to passively advected scalar field (the nonlinearity of the Hwa-Kardar model is irrelevant) and to the "pure" Hwa-Kardar model (the advection is irrelevant). For the special case ξ = 2(4 - d)/3 both the nonlinearity and the advection are important. The corresponding critical exponents are found exactly for all these cases.

  5. Voluntary Organizations and Community Groups as New Partners in Diabetes Self-management and Education: A Critical Interpretative Synthesis.

    PubMed

    Portillo, Mari Carmen; Regaira, Elena; Pumar-Méndez, María J; Mujika, Agurtzane; Vassilev, Ivaylo; Rogers, Anne; Wensing, Michel; Foss, Christina; Ruud Knutsen, Ingrid; Todorova, Elka; Roukova, Poli; Kennedy, Anne; Serrano, Manuel; Lionis, Christos; Angelaki, Agapi; Patelarou, Evridiki; Koetsenruijter, Jan

    2015-10-01

    The purpose of this study is to critically review the literature on the role and work of voluntary organizations and community groups and volunteers in diabetes self-management programs. It seeks to explain how these organizations are located and could be integrated further within a broader system of support. A critical interpretative synthesis of the literature was undertaken as part of the conceptual development of a European research project. Evidence (2000-November 2014) was searched in databases, with the use of key terms, and limited to the languages of the participating countries. This was supplemented by an additional hand search and snowballing technique. A total of 21 articles were included in the review. Evidence regarding the involvement of voluntary organizations in diabetes self-management programs mainly related to: the nature and remit of their work, responsibilities, and attributes; key strategies of programs accounting for success; motivations/barriers for engaging in volunteering participation; relationships between volunteers and users; and connections/tensions with formal services. This review has uncovered a range of facets of voluntary organizations and community groups relevant for supporting diabetes self-management such as the context within which they act and the nature of relationships developed with community and health services. The principles of "assistance, support, sharing, and link" seem essential for this voluntary initiative in self-management to establish effective reciprocal collaboration with health professionals. © 2015 The Author(s).

  6. Uncertainties in aerosol deposition within the respiratory tract using the icrp 66 model: a study in workers.

    PubMed

    Fritsch, P

    2006-02-01

    This study estimates uncertainties in aerosol deposition within the main regions of the human respiratory tract calculated using the ICRP 66 model. Uniform, triangular, normal, or lognormal distributions were assigned to the model parameters, which involve physical properties of aerosols, their inhalability, their thermo- and aerodynamic deposition efficiencies, and the anatomy, physiology, and exertion level of the individuals. Calculations were performed over a range of aerosol sizes from 0.01 to 50 mum. Monodispersed aerosols were characterized by their aerodynamic diameter (dae). Polydispersed aerosols were characterized by their activity median aerodynamic diameters (AMADs) and the geometric standard deviation (GSD) in diameter. Lognormal distributions of particle deposition were generally observed with low GSD (< 2). The highest uncertainties were observed within the deep lung for the smallest and the largest aerosol sizes, which were mainly due either to particle density or to aerodynamic deposition efficiencies and anatomical and physiological variability, respectively. In the case of diameters larger than 5 mum, uncertainties in the deep lung deposition were much more important for monodispersed than for polydispersed aerosols. This was explained both by the size distribution of the deposited aerosol, the median of which corresponded to a maximal dae value of about 7 and 5 in bronchioles and alveoli, respectively, and by the absence of deposition, which occurs for dae equal to or larger than 50 mum, depending on the exertion level. Thus, in the range of AMADs considered, for the four default workers proposed by ICRP 66, uncertainties in aerosol deposition remain low, with GSD smaller than 3.

  7. Internal dosimetry with the Monte Carlo code GATE: validation using the ICRP/ICRU female reference computational model

    NASA Astrophysics Data System (ADS)

    Villoing, Daphnée; Marcatili, Sara; Garcia, Marie-Paule; Bardiès, Manuel

    2017-03-01

    The purpose of this work was to validate GATE-based clinical scale absorbed dose calculations in nuclear medicine dosimetry. GATE (version 6.2) and MCNPX (version 2.7.a) were used to derive dosimetric parameters (absorbed fractions, specific absorbed fractions and S-values) for the reference female computational model proposed by the International Commission on Radiological Protection in ICRP report 110. Monoenergetic photons and electrons (from 50 keV to 2 MeV) and four isotopes currently used in nuclear medicine (fluorine-18, lutetium-177, iodine-131 and yttrium-90) were investigated. Absorbed fractions, specific absorbed fractions and S-values were generated with GATE and MCNPX for 12 regions of interest in the ICRP 110 female computational model, thereby leading to 144 source/target pair configurations. Relative differences between GATE and MCNPX obtained in specific configurations (self-irradiation or cross-irradiation) are presented. Relative differences in absorbed fractions, specific absorbed fractions or S-values are below 10%, and in most cases less than 5%. Dosimetric results generated with GATE for the 12 volumes of interest are available as supplemental data. GATE can be safely used for radiopharmaceutical dosimetry at the clinical scale. This makes GATE a viable option for Monte Carlo modelling of both imaging and absorbed dose in nuclear medicine.

  8. Intake retention fractions developed from models used in the determination of dose coefficients developed for ICRP publication 68--particulate inhalation.

    PubMed

    Potter, Charles A

    2002-11-01

    ICRP Publication 68 presents dose coefficients developed using systems of new models for the respiratory tract and metabolism of certain elements. The utility of these dose coefficients and associated models is limited without a method for calculating intake from bioassay results using the same models as in that publication. The calculation of a radionuclide intake requires values of expected fractions of the intake in bioassay samples collected at specific times after intake. The general system of models has been solved using a commercial software package and a method for solution of systems of first-order linear differential equations that uses eigenvectors and eigenvalues derived from the system of equations. The result of this work is a series of tables of fractions of acute inhalation intakes for different bioassay methods, times, and compound classes for intakes for those elements listed in ICRP Publication 68. The values in these tables can be used for intake calculations, development of bioassay frequencies, and development of action levels.

  9. Structure, process and annual intensive care unit mortality across 69 centers: United States Critical Illness and Injury Trials Group Critical Illness Outcomes Study (USCIITG-CIOS)

    PubMed Central

    Checkley, William; Martin, Greg S; Brown, Samuel M; Chang, Steven Y; Dabbagh, Ousama; Fremont, Richard D; Girard, Timothy D; Rice, Todd W; Howell, Michael D; Johnson, Steven B; O'Brien, James; Park, Pauline K; Pastores, Stephen M; Patil, Namrata T; Pietropaoli, Anthony P; Putman, Maryann; Rotello, Leo; Siner, Jonathan; Sajid, Sahul; Murphy, David J; Sevransky, Jonathan E

    2014-01-01

    Objective Hospital-level variations in structure and process may affect clinical outcomes in intensive care units (ICUs). We sought to characterize the organizational structure, processes of care, use of protocols and standardized outcomes in a large sample of U.S. ICUs. Design We surveyed 69 ICUs about organization, size, volume, staffing, processes of care, use of protocols, and annual ICU mortality. Setting ICUs participating in the United States Critical Illness and Injury Trials Group Critical Illness Outcomes Study (USCIITG-CIOS). Measurements and Main Results We characterized structure and process variables across ICUs, investigated relationships between these variables and annual ICU mortality, and adjusted for illness severity using APACHE II. Ninety-four ICU directors were invited to participate in the study and 69 ICUs (73%) were enrolled, of which 25 (36%) were medical, 24 were surgical (35%) and 20 (29%) were of mixed type, and 64 (93%) were located in teaching hospitals with a median number of 5 trainees per ICU. Average annual ICU mortality was 10.8%, average APACHE II score was 19.3, 58% were closed units and 41% had a 24-hour in-house intensivist. In multivariable linear regression adjusted for APACHE II and multiple ICU structure and process factors, annual ICU mortality was lower in surgical ICUs than in medical ICUs (5.6% lower, 95% CI 2.4%–8.8%) or mixed ICUs (4.5% lower, 95% CI 0.4%–8.7%). We also found a lower annual ICU mortality among ICUs that had a daily plan of care review (5.8% lower, 95% CI 1.6%–10.0%) and a lower bed-to-nurse ratio (1.8% lower when the ratio decreased from 2:1 to 1.5:1; 95% CI 0.25%–3.4%). In contrast, 24-hour intensivist coverage (p=0.89) and closed ICU status (p=0.16) were not associated with a lower annual ICU mortality. Conclusions In a sample of 69 ICUs, a daily plan of care review and a lower bed-to-nurse ratio were both associated with a lower annual ICU mortality. In contrast to 24-hour intensivist

  10. Structure, process, and annual ICU mortality across 69 centers: United States Critical Illness and Injury Trials Group Critical Illness Outcomes Study.

    PubMed

    Checkley, William; Martin, Greg S; Brown, Samuel M; Chang, Steven Y; Dabbagh, Ousama; Fremont, Richard D; Girard, Timothy D; Rice, Todd W; Howell, Michael D; Johnson, Steven B; O'Brien, James; Park, Pauline K; Pastores, Stephen M; Patil, Namrata T; Pietropaoli, Anthony P; Putman, Maryann; Rotello, Leo; Siner, Jonathan; Sajid, Sahul; Murphy, David J; Sevransky, Jonathan E

    2014-02-01

    Hospital-level variations in structure and process may affect clinical outcomes in ICUs. We sought to characterize the organizational structure, processes of care, use of protocols, and standardized outcomes in a large sample of U.S. ICUs. We surveyed 69 ICUs about organization, size, volume, staffing, processes of care, use of protocols, and annual ICU mortality. ICUs participating in the United States Critical Illness and Injury Trials Group Critical Illness Outcomes Study. Sixty-nine intensivists completed the survey. We characterized structure and process variables across ICUs, investigated relationships between these variables and annual ICU mortality, and adjusted for illness severity using Acute Physiology and Chronic Health Evaluation II. Ninety-four ICU directors were invited to participate in the study and 69 ICUs (73%) were enrolled, of which 25 (36%) were medical, 24 (35%) were surgical, and 20 (29%) were of mixed type, and 64 (93%) were located in teaching hospitals with a median number of five trainees per ICU. Average annual ICU mortality was 10.8%, average Acute Physiology and Chronic Health Evaluation II score was 19.3, 58% were closed units, and 41% had a 24-hour in-house intensivist. In multivariable linear regression adjusted for Acute Physiology and Chronic Health Evaluation II and multiple ICU structure and process factors, annual ICU mortality was lower in surgical ICUs than in medical ICUs (5.6% lower [95% CI, 2.4-8.8%]) or mixed ICUs (4.5% lower [95% CI, 0.4-8.7%]). We also found a lower annual ICU mortality among ICUs that had a daily plan of care review (5.8% lower [95% CI, 1.6-10.0%]) and a lower bed-to-nurse ratio (1.8% lower when the ratio decreased from 2:1 to 1.5:1 [95% CI, 0.25-3.4%]). In contrast, 24-hour intensivist coverage (p = 0.89) and closed ICU status (p = 0.16) were not associated with a lower annual ICU mortality. In a sample of 69 ICUs, a daily plan of care review and a lower bed-to-nurse ratio were both associated with a

  11. The impact of the draft 2005 recommendations of ICRP on secondary derived regulatory values being considered by the US Department of Energy.

    PubMed

    O'Connell, P

    2006-01-01

    The US Department of Energy, Office of Environment, Safety and Health, Office of Health is responsible for maintaining the Department of Energy's occupational radiation protection rule, Title 10 Code of Federal Regulations, Part 835, Occupational Radiation Protection. The Department of Energy is evaluating amending its rule to include the dose assessment methodology recommended in International Commission on Radiological Protection (ICRP) Publications 60 and 68. On 21 June 2004 the ICRP posted their draft, Recommendations of the International Commission on Radiological Protection 2005, which included revisions to the recommended dose assessment methodology. The Department of Energy compared the draft recommendations to determine their effect on the changes the Department of Energy is currently considering.

  12. Critical rearing parameters of Tetrastichus planipennisi (Hymenoptera: Eulophidae) as affected by host plant substrate and host-parasitoid group structure.

    PubMed

    Duan, Jian J; Oppel, Craig

    2012-06-01

    In laboratory assays, we evaluated the potential impact of host plant substrate types, host-parasitoid group sizes (densities), and parasitoid-to-host ratios on select fitness parameters of the larval endoparasitoid Tetrastichus planipennisi Yang (Hymenoptera: Eulophidae), newly introduced for biological control of emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae), in the United States. Results from our study showed that offspring production and critical fitness parameters (body size and sex ratio) of T. planipennisi from parasitized emerald ash borer larvae are significantly influenced by host plant substrate type, host-parasitoid group size, parasitoid-to-host ratio, or a combination in the primary exposure assay. The number of both female and male T. planipennisi progeny was significantly greater when emerald ash borer larvae were inserted into tropical ash [Fraxinus uhdei (Wenz.) Lingelsh.] logs rather than green ash (Fraxinus pensylvanica Marshall). When maintained at a constant 1:1 parasitoid-to-host ratio, assays with larger host-parasitoid group sizes (3:3-12:12) produced significantly greater numbers of both male and female offspring per parental wasp compared with those with the single host-parasitoid (1:1) group treatment. As the parasitoid-to-host ratio increased from 1:1 to 8:1 in the assay, the average brood size (number of offspring per parasitized emerald ash borer larva) increased significantly, whereas the average brood sex ratio (female to male) changed from being female-biased (6:1) to male-biased (1:2); body size of female offspring as measured by the length of ovipositor and left hind tibia also was reduced significantly. Based on these findings, we suggest that the current method of rearing T. planipennisi with artificially infested-emerald ash borer larvae use the tropical ash logs for emerald ash borer insertion, a larger (> or = 3:3) host-parasitoid group size and 1:1 parasitoid-to-host ratio in the primary

  13. Iron efflux by PmtA is critical for oxidative stress resistance and contributes significantly to group A streptococcus virulence.

    PubMed

    VanderWal, Arica R; Makthal, Nishanth; Pinochet-Barros, Azul; Helmann, John D; Olsen, Randall J; Kumaraswami, Muthiah

    2017-03-27

    Group A streptococcus (GAS) is a human-only pathogen that causes a spectrum of disease conditions. Given its survival in inflamed lesions, the ability to sense and overcome oxidative stress is critical for GAS pathogenesis. PerR senses oxidative stress and coordinates the regulation of genes involved in GAS antioxidant defenses. In this study, we investigated the role of PerR-controlled metal transporter A (PmtA) in GAS pathogenesis. Previously, PmtA was implicated in GAS antioxidant defenses and suggested to protect against zinc toxicity. Here, we report that PmtA is a P1B4-type ATPase that functions as an Fe(II) exporter and aids GAS defenses against iron intoxication and oxidative stress. Expression of pmtA is specifically induced by iron excess and this induction requires PerR. Furthermore, the pmtA mutant exhibited increased sensitivity to iron toxicity and oxidative stress due to elevated intracellular accumulation of iron. RNA-sequencing analysis revealed that GAS undergoes significant alterations in gene expression to adapt to iron toxicity. Finally, using two mouse models of invasive infection, we demonstrated that iron efflux by PmtA is critical for bacterial survival during infection and GAS virulence. Together, these data demonstrate that PmtA is a key component of GAS antioxidant defenses and contributes significantly to GAS virulence.

  14. Unsteady Reynolds averaged Navier-Stokes simulation of the post-critical flow around a closely spaced group of silos

    NASA Astrophysics Data System (ADS)

    Hillewaere, J.; Dooms, D.; Van Quekelberghe, B.; Degroote, J.; Vierendeels, J.; De Roeck, G.; Lombaert, G.; Degrande, G.

    2012-04-01

    During a storm in October 2002, wind induced ovalling vibrations were observed on several empty silos of a closely spaced group (pitch-to-diameter ratio of 1.05) consisting of 8 by 5 silos in the port of Antwerp (Belgium). Numerical simulations of the turbulent wind flow are performed to clarify the occurrence of the observed ovalling vibrations near the lee side corner of the group by studying the dynamic wind pressures on the silo surfaces and linking to the dynamic properties of the silo structures. As the orientation of the group largely affects the pressure distribution around the cylinders of the group, the influence of the angle of incidence of the wind flow on these ovalling vibrations is examined while other parameters, such as spacing ratio and Reynolds number are unchanged. To achieve results within a reasonable computation time, 2D unsteady Reynolds averaged Navier-Stokes (URANS) equations using Menter's shear stress transport turbulence model were performed. In order to elucidate the influence of the applied turbulence model and to qualitatively validate the spatial and temporal discretization of the 2D highly turbulent post-critical (Re=1.24×107) flow simulations for the silo group, single cylinder simulations were used. The geometric resemblance of the group arrangement with rectangular cylinders on the one hand and of the interstitial spaces with tube arrays (e.g. heat exchangers) on the other hand is used to qualitatively compare the observed flow phenomena. The simulations show that the silo group can be treated neither as a tube array nor as a solid bluff body. Subsequent linking of dynamic wind pressures to dynamic properties of the silo structures reveals strong narrow band frequency peaks in the turbulent pressure coefficient spectra of the silos near the lee side corners of the group that match the structural natural frequencies of the third and fourth ovalling mode shape of the silos. This match indicates a forced, resonant response which

  15. Higgs amplitude mode in the vicinity of a (2 +1 ) -dimensional quantum critical point: A nonperturbative renormalization-group approach

    NASA Astrophysics Data System (ADS)

    Rose, F.; Léonard, F.; Dupuis, N.

    2015-06-01

    We study the "Higgs" amplitude mode in the relativistic quantum O (N ) model in two space dimensions. Using the nonperturbative renormalization group and the Blaizot-Méndez-Galain-Wschebor approximation (which we generalize to compute four-point correlation functions), we compute the O (N ) -invariant scalar susceptibility at zero temperature in the vicinity of the quantum critical point. In the ordered phase, we find a well-defined Higgs resonance for N =2 and 3 and determine its universal properties. No resonance is found for N ≥4 . In the disordered phase, the spectral function exhibits a threshold behavior with no Higgs-like peak. We also show that for N =2 , the Higgs mode manifests itself as a very broad peak in the longitudinal susceptibility in spite of the infrared divergence of the latter. We compare our findings with results from quantum Monte Carlo simulations and ɛ =4 -(d +1 ) expansion near d =3 .

  16. Critical Evaluation of Thermochemical Properties of C1-C4 Species: Updated Group-Contributions to Estimate Thermochemical Properties

    NASA Astrophysics Data System (ADS)

    Burke, S. M.; Simmie, J. M.; Curran, H. J.

    2015-03-01

    A review of literature on enthalpies of formation and molar entropies for alkanes, alkenes, alcohols, hydroperoxides, and their associated radicals has been compiled and critically evaluated. By comparing literature values, the overall uncertainty in thermochemical properties of small hydrocarbons and oxygenated hydrocarbons can be highlighted. In general, there is good agreement between heat of formation values in the literature for stable species; however, there is greater uncertainty in the values for radical species and for molar entropy values. Updated values for a group-additivity method for the estimation of thermochemical properties based on the evaluated literature data are proposed. The new values can be used to estimate thermochemical data for larger, combustion-relevant species for which no calculations or measurements currently exist, with increased confidence.

  17. CSRL-V ENDF/B-V 227-group neutron cross-section library and its application to thermal-reactor and criticality safety benchmarks

    SciTech Connect

    Ford, W.E. III; Diggs, B.R.; Knight, J.R.; Greene, N.M.; Petrie, L.M.; Webster, C.C.; Westfall, R.M.; Wright, R.Q.; Williams, M.L.

    1982-01-01

    Characteristics and contents of the CSRL-V (Criticality Safety Reference Library based on ENDF/B-V data) 227-neutron-group AMPX master and pointwise cross-section libraries are described. Results obtained in using CSRL-V to calculate performance parameters of selected thermal reactor and criticality safety benchmarks are discussed.

  18. An image-based skeletal dosimetry model for the ICRP reference adult female-internal electron sources.

    PubMed

    O'Reilly, Shannon E; DeWeese, Lindsay S; Maynard, Matthew R; Rajon, Didier A; Wayson, Michael B; Marshall, Emily L; Bolch, Wesley E

    2016-12-21

    An image-based skeletal dosimetry model for internal electron sources was created for the ICRP-defined reference adult female. Many previous skeletal dosimetry models, which are still employed in commonly used internal dosimetry software, do not properly account for electron escape from trabecular spongiosa, electron cross-fire from cortical bone, and the impact of marrow cellularity on active marrow self-irradiation. Furthermore, these existing models do not employ the current ICRP definition of a 50 µm bone endosteum (or shallow marrow). Each of these limitations was addressed in the present study. Electron transport was completed to determine specific absorbed fractions to both active and shallow marrow of the skeletal regions of the University of Florida reference adult female. The skeletal macrostructure and microstructure were modeled separately. The bone macrostructure was based on the whole-body hybrid computational phantom of the UF series of reference models, while the bone microstructure was derived from microCT images of skeletal region samples taken from a 45 years-old female cadaver. The active and shallow marrow are typically adopted as surrogate tissue regions for the hematopoietic stem cells and osteoprogenitor cells, respectively. Source tissues included active marrow, inactive marrow, trabecular bone volume, trabecular bone surfaces, cortical bone volume, and cortical bone surfaces. Marrow cellularity was varied from 10 to 100 percent for active marrow self-irradiation. All other sources were run at the defined ICRP Publication 70 cellularity for each bone site. A total of 33 discrete electron energies, ranging from 1 keV to 10 MeV, were either simulated or analytically modeled. The method of combining skeletal macrostructure and microstructure absorbed fractions assessed using MCNPX electron transport was found to yield results similar to those determined with the PIRT model applied to the UF adult male skeletal dosimetry model. Calculated

  19. An image-based skeletal dosimetry model for the ICRP reference adult female—internal electron sources

    NASA Astrophysics Data System (ADS)

    O'Reilly, Shannon E.; DeWeese, Lindsay S.; Maynard, Matthew R.; Rajon, Didier A.; Wayson, Michael B.; Marshall, Emily L.; Bolch, Wesley E.

    2016-12-01

    An image-based skeletal dosimetry model for internal electron sources was created for the ICRP-defined reference adult female. Many previous skeletal dosimetry models, which are still employed in commonly used internal dosimetry software, do not properly account for electron escape from trabecular spongiosa, electron cross-fire from cortical bone, and the impact of marrow cellularity on active marrow self-irradiation. Furthermore, these existing models do not employ the current ICRP definition of a 50 µm bone endosteum (or shallow marrow). Each of these limitations was addressed in the present study. Electron transport was completed to determine specific absorbed fractions to both active and shallow marrow of the skeletal regions of the University of Florida reference adult female. The skeletal macrostructure and microstructure were modeled separately. The bone macrostructure was based on the whole-body hybrid computational phantom of the UF series of reference models, while the bone microstructure was derived from microCT images of skeletal region samples taken from a 45 years-old female cadaver. The active and shallow marrow are typically adopted as surrogate tissue regions for the hematopoietic stem cells and osteoprogenitor cells, respectively. Source tissues included active marrow, inactive marrow, trabecular bone volume, trabecular bone surfaces, cortical bone volume, and cortical bone surfaces. Marrow cellularity was varied from 10 to 100 percent for active marrow self-irradiation. All other sources were run at the defined ICRP Publication 70 cellularity for each bone site. A total of 33 discrete electron energies, ranging from 1 keV to 10 MeV, were either simulated or analytically modeled. The method of combining skeletal macrostructure and microstructure absorbed fractions assessed using MCNPX electron transport was found to yield results similar to those determined with the PIRT model applied to the UF adult male skeletal dosimetry model. Calculated

  20. The David and Goliath principle: cultural, ideological, and attitudinal underpinnings of the normative protection of low-status groups from criticism.

    PubMed

    Jeffries, Carla H; Hornsey, Matthew J; Sutton, Robbie M; Douglas, Karen M; Bain, Paul G

    2012-08-01

    Two studies documented the "David and Goliath" rule--the tendency for people to perceive criticism of "David" groups (groups with low power and status) as less normatively permissible than criticism of "Goliath" groups (groups with high power and status). The authors confirmed the existence of the David and Goliath rule across Western and Chinese cultures (Study 1). However, the rule was endorsed more strongly in Western than in Chinese cultures, an effect mediated by cultural differences in power distance. Study 2 identified the psychological underpinnings of this rule in an Australian sample. Lower social dominance orientation (SDO) was associated with greater endorsement of the rule, an effect mediated through the differential attribution of stereotypes. Specifically, those low in SDO were more likely to attribute traits of warmth and incompetence to David versus Goliath groups, a pattern of stereotypes that was related to the protection of David groups from criticism.

  1. Evaluation of organ doses and effective dose according to the ICRP Publication 110 reference male/female phantom and the modified ImPACT CT patient dosimetry.

    PubMed

    Kobayashi, Masanao; Asada, Yasuki; Matsubara, Kosuke; Matsunaga, Yuta; Kawaguchi, Ai; Katada, Kazuhiro; Toyama, Hiroshi; Koshida, Kichiro; Suzuki, Shouichi

    2014-09-07

    We modified the Imaging Performance Assessment of CT scanners (ImPACT) to evaluate the organ doses and the effective dose based on the International Commission on Radiological Protection (ICRP) Publication 110 reference male/female phantom with the Aquilion ONE ViSION Edition scanner. To select the new CT scanner, the measurement results of the CTDI100,c and CTDI100,p for the 160 (head) and the 320 (body) mm polymethylmethacrylate phantoms, respectively, were entered on the Excel worksheet. To compute the organ doses and effective dose of the ICRP reference male/female phantom, the conversion factors obtained by comparison between the organ doses of different types of phantom were applied. The organ doses and the effective dose were almost identical for the ICRP reference male/female and modified ImPACT. The results of this study showed that, with the dose assessment of the ImPACT, the difference in sex influences only testes and ovaries. Because the MIRD-5 phantom represents a partially hermaphrodite adult, the phantom has the dimensions of the male reference man including testes, ovaries, and uterus but no female breasts, whereas the ICRP male/female phantom includes whole-body male and female anatomies based on high-resolution anatomical datasets. The conversion factors can be used to estimate the doses of a male and a female accurately, and efficient dose assessment can be performed with the modified ImPACT.

  2. Consideration of the ICRP 2006 revised tissue weighting factors on age-dependent values of the effective dose for external photons

    NASA Astrophysics Data System (ADS)

    Lee, Choonsik; Lee, Choonik; Han, Eun Young; Bolch, Wesley E.

    2007-01-01

    The effective dose recommended by the International Commission on Radiological Protection (ICRP) is the sum of organ equivalent doses weighted by corresponding tissue weighting factors, wT. ICRP is in the process of revising its 1990 recommendations on the effective dose where new values of organs and tissue weighting factors have been proposed and published in draft form for consultation by the radiological protection community. In its 5 June 2006 draft recommendations, new organs and tissues have been introduced in the effective dose which do not exist within the 1987 Oak Ridge National Laboratory (ORNL) phantom series (e.g., salivary glands). Recently, the investigators at University of Florida have updated the series of ORNL phantoms by implementing new organ models and adopting organ-specific elemental composition and densities. In this study, the effective dose changes caused by the transition from the current recommendation of ICRP Publication 60 to the 2006 draft recommendations were investigated for external photon irradiation across the range of ICRP reference ages (newborn, 1-year, 5-year, 10-year, 15-year and adult) and for six idealized irradiation geometries: anterior-posterior (AP), posterior-anterior (PA), left-lateral (LLAT), right-lateral (RLAT), rotational (ROT) and isotropic (ISO). Organ-absorbed doses were calculated by implementing the revised ORNL phantoms in the Monte Carlo radiation transport code, MCNPX2.5, after which effective doses were calculated under the 1990 and draft 2006 evaluation schemes of the ICRP. Effective doses calculated under the 2006 draft scheme were slightly higher than estimated under ICRP Publication 60 methods for all irradiation geometries exclusive of the AP geometry where an opposite trend was observed. The effective doses of the adult phantom were more greatly affected by the change in tissue weighting factors than that seen within the paediatric members of the phantom series. Additionally, dose conversion

  3. Comparison of ICRP 67 and Other Plutonium Systemic Model Predictions with the Biokinetic Data from Nonhuman Primates.

    PubMed

    Poudel, Deepesh; Krage, Eric Stephen; Brey, Richard Ray; Guilmette, Raymond A

    2016-04-01

    Despite the presence of a relatively large amount of human data available on the metabolism of plutonium, the experimental animal data is still important in constructing and parameterizing the biokinetic models. Recognizing this importance, the biokinetic data obtained from studies done by P.W. Durbin in nonhuman primates (NHP) were evaluated against the ICRP 67 systemic model and the two human models developed thereafter. The default transfer rates recommended for adult humans in these models predict the urinary excretion in NHP to a certain extent. However, they were unable to describe the fecal excretion rates several days post intake and the activities in skeleton and liver at the time of the death. These inconsistencies between the human reference models and the NHP biokinetic data are the result of metabolic and physiological differences between the species, as demonstrated by early biokinetic studies.

  4. Workshop to identify critical windows of exposure for children's health: reproductive health in children and adolescents work group summary.

    PubMed Central

    Lemasters, G K; Perreault, S D; Hales, B F; Hatch, M; Hirshfield, A N; Hughes, C L; Kimmel, G L; Lamb, J C; Pryor, J L; Rubin, C; Seed, J G

    2000-01-01

    This work group report addresses the central question: What are the critical windows during development (preconception through puberty) when exposure to xenobiotics may have the greatest adverse impact on subsequent reproductive health? The reproductive system develops in stages, with sex-specific organogenesis occurring prenatally and further maturational events occurring in the perinatal period and at puberty. Complex endocrine signals as well as other regulatory factors (genetics, growth factors) are involved at all stages. Evidence from animal models and human studies indicates that many specific events can be perturbed by a variety of toxicants, with endocrine-mediated mechanisms being the more widely studied. Prioritized research needs include basic studies on the cellular-molecular and endocrine regulation of sexual differentiation and development; increased efforts regarding potential adverse effects on development in females, including breast development; expanded animal studies on different classes of chemicals, comparing responses during development (prenatal and postnatal) with responses in adults; and, more extensive explorations regarding the reproductive biology and toxicology of puberty in humans. PMID:10852850

  5. Curricular initiatives that enhance student knowledge and perceptions of sexual and gender minority groups: a critical interpretive synthesis

    PubMed Central

    Desrosiers, Jennifer; Wilkinson, Tim; Abel, Gillian; Pitama, Suzanne

    2016-01-01

    Background There is no accepted best practice for optimizing tertiary student knowledge, perceptions, and skills to care for sexual and gender diverse groups. The objective of this research was to synthesize the relevant literature regarding effective curricular initiatives designed to enhance tertiary level student knowledge, perceptions, and skills to care for sexual and gender diverse populations. Methods A modified Critical Interpretive Synthesis using a systematic search strategy was conducted in 2015. This method was chosen to synthesize the relevant qualitative and quantitative literature as it allows for the depth and breadth of information to be captured and new constructs to be illuminated. Databases searched include AMED, CINAHL EBM Reviews, ERIC, Ovid MEDLINE, Ovid Nursing Database, PsychInfo, and Google Scholar. Results Thirty-one articles were included in this review. Curricular initiatives ranging from discrete to multimodal approaches have been implemented. Successful initiatives included discrete sessions with time for processing, and multi-modal strategies. Multi-modal approaches that encouraged awareness of one’s lens and privilege in conjunction with facilitated communication seemed the most effective. Conclusions The literature is limited to the evaluation of explicit curricula. The wider cultural competence literature offers further insight by highlighting the importance of broad and embedded forces including social influences, the institutional climate, and the implicit, or hidden, curriculum. A combined interpretation of the complementary cultural competence and sexual and gender diversity literature provides a novel understanding of the optimal content and context for the delivery of a successful curricular initiative. PMID:28344699

  6. [Clinical hygienic substantiation for the individual biocorrection of ecologically dependent conditions in the critical population groups industrial areas of Ukraine].

    PubMed

    Beletskaya, E N; Onul, N M; Glavatskaya, V I; Antonova, E V; Golovkova, T A

    2014-01-01

    In the article there is considered the problem of environmental and human body pollution with heavy metals, the effectiveness of individual biocorrection in critical population groups--pregnant females and children residing in technologically contaminated areas. It was established that, in spite of the correspondence of the content of abiotic heavy metals to their MACs in the environment, the concentration of lead and cadmium in the internal environment of the organism is 1,6-15,4 times larger than physiological norms and accompanied by substantial deficiency of essential trace elements. The similar situation in children was proved to cause the fall in mental capacity and learning ability, in pregnant females--to various complications. The obtained results were the scientific substantiation for the feasibility of performing of biocorrection for trace elements imbalance and ecologically dependent conditions in the population of the industrial region, proved its high clinical and hygienic efficiency, which is the basis for the wide introduction of pectin containing preparations with the aim to enforce the health, prevent ecologically dependent conditions and increasing the adaptive capacity of the organism.

  7. Assessing Economic Modulation of Future Critical Materials Use: The Case of Automotive-Related Platinum Group Metals.

    PubMed

    Zhang, Jingshu; Everson, Mark P; Wallington, Timothy J; Field, Frank R; Roth, Richard; Kirchain, Randolph E

    2016-07-19

    Platinum-group metals (PGMs) are technological and economic enablers of many industrial processes. This important role, coupled with their limited geographic availability, has led to PGMs being labeled as "critical materials". Studies of future PGM flows have focused on trends within material flows or macroeconomic indicators. We complement the previous work by introducing a novel technoeconomic model of substitution among PGMs within the automotive sector (the largest user of PGMs) reflecting the rational response of firms to changing prices. The results from the model support previous conclusions that PGM use is likely to grow, in some cases strongly, by 2030 (approximately 45% for Pd and 5% for Pt), driven by the increasing sales of automobiles. The model also indicates that PGM-demand growth will be significantly influenced by the future Pt-to-Pd price ratio, with swings of Pt and Pd demand of as much as 25% if the future price ratio shifts higher or lower even if it stays within the historic range. Fortunately, automotive catalysts are one of the more effectively recycled metals. As such, with proper policy support, recycling can serve to meet some of this growing demand.

  8. The Influence of Ground Rules on Chinese Students' Learning of Critical Thinking in Group Work: A Cultural Perspective

    ERIC Educational Resources Information Center

    Fung, Dennis

    2014-01-01

    This article reports the results of a one-year longitudinal study examining a teaching intervention designed to enhance students' learning of critical thinking in Hong Kong. Seventy participating students (age 16-18) learned how to make reasoned arguments through a series of collaborative activities, including critical-thinking modelling tasks and…

  9. The Influence of Ground Rules on Chinese Students' Learning of Critical Thinking in Group Work: A Cultural Perspective

    ERIC Educational Resources Information Center

    Fung, Dennis

    2014-01-01

    This article reports the results of a one-year longitudinal study examining a teaching intervention designed to enhance students' learning of critical thinking in Hong Kong. Seventy participating students (age 16-18) learned how to make reasoned arguments through a series of collaborative activities, including critical-thinking modelling tasks and…

  10. Critical appraisal of the International Study Group of Pancreatic Surgery (ISGPS) consensus definition of postoperative hemorrhage after pancreatoduodenectomy.

    PubMed

    Welsch, Thilo; Eisele, Hanna; Zschäbitz, Stefanie; Hinz, Ulf; Büchler, Markus W; Wente, Moritz N

    2011-08-01

    Postpancreatectomy hemorrhage (PPH) is one of the most serious complications after pancreatoduodenectomy (PD). This study analyzed and validated the International Study Group of Pancreatic Surgery (ISGPS) definition of PPH and aimed to identify risk factors for early (<24 h) and late PPH. Patients who underwent PD for pancreatic head tumors between 2001 and 2008 were included and complications were prospectively recorded. Factors associated with PPH were assessed by uni- and multivariate analysis. Complete datasets were available for 796 patients. Classic and pylorus-preserving PD was performed in 13.8% and 86.2% of the patients, respectively. According to the ISGPS definition, PPH occurred in 29.1% of the cases (232 of 796 patients): 4.8% grade A, 15.2% grade B, and 9.2% grade C. The definition is based largely on surrogate markers (e.g., transfusion requirement) that are affected by other critical illnesses and more than 97% of patients with mild PPH had no clinical signs of bleeding. The need for postoperative intensive care as well as the incidence of pancreatic fistula, relaparotomy, and mortality rates significantly increased from grades A to C. Thirty-seven patients (4.6%) required interventional (endoscopy or angiography) and/or relaparotomy for PPH. Relaparotomy for PPH was performed in 3.1% of all patients. Independent risk factors for early PPH were preoperative anemia (hemoglobin, <11 mg/dl) and multivisceral resection while advanced age, chronic renal insufficiency, increased blood loss, and long operation time were associated with late PPH. The ISGPS definition of PPH is feasible and applicable but produces a high rate of false positive mild PPH cases. The different grades still significantly correlate with relevant outcome variables, thus the definition discriminates postoperative courses, but a minor modification of the definition of mild PPH is suggested. The new results further demonstrate the need to optimize preoperative anemia and chronic renal

  11. An image-based skeletal dosimetry model for the ICRP reference adult male--internal electron sources.

    PubMed

    Hough, Matthew; Johnson, Perry; Rajon, Didier; Jokisch, Derek; Lee, Choonsik; Bolch, Wesley

    2011-04-21

    In this study, a comprehensive electron dosimetry model of the adult male skeletal tissues is presented. The model is constructed using the University of Florida adult male hybrid phantom of Lee et al (2010 Phys. Med. Biol. 55 339-63) and the EGSnrc-based Paired Image Radiation Transport code of Shah et al (2005 J. Nucl. Med. 46 344-53). Target tissues include the active bone marrow, associated with radiogenic leukemia, and total shallow marrow, associated with radiogenic bone cancer. Monoenergetic electron emissions are considered over the energy range 1 keV to 10 MeV for the following sources: bone marrow (active and inactive), trabecular bone (surfaces and volumes), and cortical bone (surfaces and volumes). Specific absorbed fractions are computed according to the MIRD schema, and are given as skeletal-averaged values in the paper with site-specific values reported in both tabular and graphical format in an electronic annex available from http://stacks.iop.org/0031-9155/56/2309/mmedia. The distribution of cortical bone and spongiosa at the macroscopic dimensions of the phantom, as well as the distribution of trabecular bone and marrow tissues at the microscopic dimensions of the phantom, is imposed through detailed analyses of whole-body ex vivo CT images (1 mm resolution) and spongiosa-specific ex vivo microCT images (30 µm resolution), respectively, taken from a 40 year male cadaver. The method utilized in this work includes: (1) explicit accounting for changes in marrow self-dose with variations in marrow cellularity, (2) explicit accounting for electron escape from spongiosa, (3) explicit consideration of spongiosa cross-fire from cortical bone, and (4) explicit consideration of the ICRP's change in the surrogate tissue region defining the location of the osteoprogenitor cells (from a 10 µm endosteal layer covering the trabecular and cortical surfaces to a 50 µm shallow marrow layer covering trabecular and medullary cavity surfaces). Skeletal

  12. An image-based skeletal dosimetry model for the ICRP reference adult male—internal electron sources

    NASA Astrophysics Data System (ADS)

    Hough, Matthew; Johnson, Perry; Rajon, Didier; Jokisch, Derek; Lee, Choonsik; Bolch, Wesley

    2011-04-01

    In this study, a comprehensive electron dosimetry model of the adult male skeletal tissues is presented. The model is constructed using the University of Florida adult male hybrid phantom of Lee et al (2010 Phys. Med. Biol. 55 339-63) and the EGSnrc-based Paired Image Radiation Transport code of Shah et al (2005 J. Nucl. Med. 46 344-53). Target tissues include the active bone marrow, associated with radiogenic leukemia, and total shallow marrow, associated with radiogenic bone cancer. Monoenergetic electron emissions are considered over the energy range 1 keV to 10 MeV for the following sources: bone marrow (active and inactive), trabecular bone (surfaces and volumes), and cortical bone (surfaces and volumes). Specific absorbed fractions are computed according to the MIRD schema, and are given as skeletal-averaged values in the paper with site-specific values reported in both tabular and graphical format in an electronic annex available from http://stacks.iop.org/0031-9155/56/2309/mmedia. The distribution of cortical bone and spongiosa at the macroscopic dimensions of the phantom, as well as the distribution of trabecular bone and marrow tissues at the microscopic dimensions of the phantom, is imposed through detailed analyses of whole-body ex vivo CT images (1 mm resolution) and spongiosa-specific ex vivo microCT images (30 µm resolution), respectively, taken from a 40 year male cadaver. The method utilized in this work includes: (1) explicit accounting for changes in marrow self-dose with variations in marrow cellularity, (2) explicit accounting for electron escape from spongiosa, (3) explicit consideration of spongiosa cross-fire from cortical bone, and (4) explicit consideration of the ICRP's change in the surrogate tissue region defining the location of the osteoprogenitor cells (from a 10 µm endosteal layer covering the trabecular and cortical surfaces to a 50 µm shallow marrow layer covering trabecular and medullary cavity surfaces). Skeletal

  13. Dietary intakes of seven elements of importance in radiological protection by asian population: comparison with ICRP data.

    PubMed

    Iyengar, G V; Kawamura, H; Dang, H S; Parr, R M; Wang, J; Akhter, Perveen; Cho, S Y; Natera, E; Miah, F K; Dojosubroto, J; Nguyen, M S

    2004-06-01

    Within the framework of a Coordinated Research Project (CRP) organized by the International Atomic Energy Agency, Vienna, the daily dietary intakes of seven elements by adult populations living in nine Asian countries were estimated. The countries that participated in the study were Bangladesh, China, India, Indonesia, Japan, Pakistan, Philippines, South Korea (Republic of Korea, ROK), and Vietnam and together they represented more than half of the world population. The seven elements studied were calcium, cesium, iodine, potassium, strontium, thorium, and uranium. These elements have chemical and biological similarity to some of the radionuclides abundantly encountered during nuclear power production and therefore data on these elements could provide important information on their biokinetic behavior. Analyses of diet samples for these seven elements were carried out using highly sensitive and reliable analytical techniques. One thousand one hundred and sixty analytical determinations were made on two hundred and twenty samples of typical diets consumed in these countries to estimate the daily intakes of these elements by the adult Asian population. The median daily dietary intakes for the adult Asian population were found to be 0.45 g calcium, 7 microg cesium, 90 microg iodine, 1.75 g potassium, 1.65 mg strontium, 1 microg thorium, and 1 microg uranium. When compared with the intakes proposed for ICRP Reference Man by International Commission for Radiological Protection, these intakes were lower by factors of 0.41 for calcium, 0.7 for cesium, 0.45 for iodine, 0.53 for potassium, 0.87 for strontium, 0.33 for thorium, and 0.52 for uranium. The lower daily intakes of calcium, cesium, and iodine by Asian population could be due to significantly lower consumption of milk and milk products, which are rich in these elements. The significantly lower intake of calcium in most of the Asian countries may lead to higher uptake of fission nuclide 90Sr and could result in

  14. Trends in Critical Care Beds and Use Among Population Groups and Medicare and Medicaid Beneficiaries in the United States: 2000-2010.

    PubMed

    Halpern, Neil A; Goldman, Debra A; Tan, Kay See; Pastores, Stephen M

    2016-08-01

    To analyze patterns of critical care medicine beds, use, and costs in acute care hospitals in the United States and relate critical care medicine beds and use to population shifts, age groups, and Medicare and Medicaid beneficiaries from 2000 to 2010. Retrospective study of data from the federal Healthcare Cost Report Information System, American Hospital Association, and U.S. Census Bureau. None. None. Acute care U.S. hospitals with critical care medicine beds. From 2000 to 2010, U.S. hospitals with critical care medicine beds decreased by 17% (3,586-2,977), whereas the U.S. population increased by 9.6% (282.2-309.3M). Although hospital beds decreased by 2.2% (655,785-641,395), critical care medicine beds increased by 17.8% (88,235-103,900), a 20.4% increase in the critical care medicine-to-hospital bed ratio (13.5-16.2%). There was a greater percentage increase in premature/neonatal (29%; 14,391-18,567) than in adult (15.9%; 71,978-83,417) or pediatric (2.7%; 1,866-1,916) critical care medicine beds. Hospital occupancy rates increased by 10.4% (58.6-64.6%), whereas critical care medicine occupancy rates were stable (range, 65-68%). Critical care medicine beds per 100,000 total population increased by 7.4% (31.3-33.6). The proportional use of critical care medicine services by Medicare beneficiaries decreased by 17.3% (37.9-31.4%), whereas that by Medicaid rose by 18.3% (14.5-17.2%). Between 2000 and 2010, annual critical care medicine costs nearly doubled (92.2%; $56-108 billion). In the same period, the proportion of critical care medicine cost to the gross domestic product increased by 32.1% (0.54-0.72%). Critical care medicine beds, use, and costs in the United States continue to rise. The increasing use of critical care medicine by the premature/neonatal and Medicaid populations should be considered by healthcare policy makers, state agencies, and hospitals as they wrestle with critical care bed growth and the associated costs.

  15. Considerations on the ICRP model predictions of the transfer of (137)Cs from food to the milk and urine of lactating mothers.

    PubMed

    Giussani, Augusto; Risica, Serena

    2014-06-01

    A recent work has shown that the current ICRP biokinetic model for the transfer of caesium radionuclides from food to human breast milk was able to describe with satisfactory accuracy (137)Cs activity concentrations in human breast samples collected a few weeks after the Chernobyl accident as well as in samples collected some years later. However, systematic discrepancies were observed for the predictions of the activity concentrations in urine samples. In the present work, modifications to the model were investigated with the aim of improving the agreement between model predictions and data. It turned out that the disagreement for the urine data was ascribable to the mathematical simplifications used by the ICRP to describe urinary excretion in the first few days after delivery. However, the predictive performances of the model remained unchanged even when differences in the bioavailability of caesium from the ingested food types were considered or metabolic interactions between caesium and potassium were introduced into the model formulation.

  16. Current risk estimates based on the A-bomb survivors data - a discussion in terms of the ICRP recommendations on the neutron weighting factor.

    PubMed

    Rühm, W; Walsh, L

    2007-01-01

    Currently, most analyses of the A-bomb survivors' solid tumour and leukaemia data are based on a constant neutron relative biological effectiveness (RBE) value of 10 that is applied to all survivors, independent of their distance to the hypocentre at the time of bombing. The results of these analyses are then used as a major basis for current risk estimates suggested by the International Commission on Radiological Protection (ICRP) for use in international safety guidelines. It is shown here that (i) a constant value of 10 is not consistent with weighting factors recommended by the ICRP for neutrons and (ii) it does not account for the hardening of the neutron spectra in Hiroshima and Nagasaki, which takes place with increasing distance from the hypocentres. The purpose of this paper is to present new RBE values for the neutrons, calculated as a function of distance from the hypocentres for both cities that are consistent with the ICRP60 neutron weighting factor. If based on neutron spectra from the DS86 dosimetry system, these calculations suggest values of about 31 at 1000 m and 23 at 2000 m ground range in Hiroshima, while the corresponding values for Nagasaki are 24 and 22. If the neutron weighting factor that is consistent with ICRP92 is used, the corresponding values are about 23 and 21 for Hiroshima and 21 and 20 for Nagasaki, respectively. It is concluded that the current risk estimates will be subject to some changes in view of the changed RBE values. This conclusion does not change significantly if the new doses from the Dosimetry System DS02 are used.

  17. Uncertainties in doses calculated according to ICRP recommendations after inhalation of 239PUO2 and early chest monitoring.

    PubMed

    Fritsch, P

    2007-01-01

    This study estimates uncertainties in Pu biokinetics and effective doses calculated after an acute inhalation exposure to 239PuO2 according to ICRP recommendations (default values for aerosols size and PuO2 dissolution parameters). This was performed using the most recently reported variations in model parameters and simulations after a Monte Carlo approach. Without chest monitoring, uncertainties in thoracic retention and plutonium excretion was 8-10 (95% confidence interval as the ratio between 97.5 and 2.5 percentiles of the lognormal distributions) up to 900 d after exposure. Early chest monitoring reduces significantly the uncertainties in plutonium biokinetics and doses which remain within a 95% confidence interval of 2.3 as compared with 6.6, without monitoring. Analysis of bioassay data previously reported shows that the dose delivered to some individuals can be out of the confidence interval, which was mostly due to an inhibition of the late mechanical clearance of the alveolar interstitium.

  18. Adaptation of the ICRP publication 66 respiratory tract model to data on plutonium biokinetics for Mayak workers.

    PubMed

    Khokhryakov, V F; Suslova, K G; Vostrotin, V V; Romanov, S A; Eckerman, K F; Krahenbuhl, M P; Miller, S C

    2005-02-01

    The biokinetics of inhaled plutonium were analyzed using compartment models representing their behavior within the respiratory tract, the gastrointestinal tract, and in systemic tissues. The processes of aerosol deposition, particle transport, absorption, and formation of a fixed deposit in the respiratory tract were formulated in the framework of the Human Respiratory Tract Model described in ICRP Publication 66. The values of parameters governing absorption and formation of the fixed deposit were established by fitting the model to the observations in 530 autopsy cases. The influence of smoking on mechanical clearance of deposited plutonium activity was considered. The dependence of absorption on the aerosol transportability, as estimated by in vitro methods (dialysis), was demonstrated. The results of this study were compared to those obtained from an earlier model of plutonium behavior in the respiratory tract, which was based on the same set of autopsy data. That model did not address the early phases of respiratory clearance and hence underestimated the committed lung dose by about 25% for plutonium oxides. Little difference in lung dose was found for nitrate forms.

  19. Fluence-to-dose conversion coefficients for neutrons and protons calculated using the PHITS code and ICRP/ICRU adult reference computational phantoms.

    PubMed

    Sato, Tatsuhiko; Endo, Akira; Zankl, Maria; Petoussi-Henss, Nina; Niita, Koji

    2009-04-07

    The fluence to organ-dose and effective-dose conversion coefficients for neutrons and protons with energies up to 100 GeV was calculated using the PHITS code coupled to male and female adult reference computational phantoms, which are to be released as a common ICRP/ICRU publication. For the calculation, the radiation and tissue weighting factors, w(R) and w(T), respectively, as revised in ICRP Publication 103 were employed. The conversion coefficients for effective dose equivalents derived using the radiation quality factors of both Q(L) and Q(y) relationships were also estimated, utilizing the functions for calculating the probability densities of the absorbed dose in terms of LET (L) and lineal energy (y), respectively, implemented in PHITS. By comparing these data with the corresponding data for the effective dose, we found that the numerical compatibilities of the revised w(R) with the Q(L) and Q(y) relationships are fairly established. The calculated data of these dose conversion coefficients are indispensable for constructing the radiation protection systems based on the new recommendations given in ICRP103 for aircrews and astronauts, as well as for workers in accelerators and nuclear facilities.

  20. A comparison of radiological risk assessment models: Risk assessment models used by the BEIR V Committee, UNSCEAR, ICRP, and EPA (for NESHAP)

    SciTech Connect

    Wahl, L.E.

    1994-03-01

    Radiological risk assessments and resulting risk estimates have been developed by numerous national and international organizations, including the National Research Council`s fifth Committee on the Biological Effects of Ionizing Radiations (BEIR V), the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), and the International Commission on Radiological Protection (ICRP). A fourth organization, the Environmental Protection Agency (EPA), has also performed a risk assessment as a basis for the National Emission Standards for Hazardous Air Pollutants (NESHAP). This paper compares the EPA`s model of risk assessment with the models used by the BEIR V Committee, UNSCEAR, and ICRP. Comparison is made of the values chosen by each organization for several model parameters: populations used in studies and population transfer coefficients, dose-response curves and dose-rate effects, risk projection methods, and risk estimates. This comparison suggests that the EPA has based its risk assessment on outdated information and that the organization should consider adopting the method used by the BEIR V Committee, UNSCEAR, or ICRP.

  1. Validation of the Monte Carlo criticality program KENO IV and the Hansen-Roach sixteen-energy-group-cross sections for high-assay uranium systems. [KENO IV criticality code

    SciTech Connect

    Handley, G. R.; Masters, L. C.; Stachowiak, R. V.

    1981-04-10

    Validation of the Monte Carlo criticality code, KENO IV, and the Hansen-Roach sixteen-energy-group cross sections was accomplished by calculating the effective neutron multiplication constant, k/sub eff/, of 29 experimentally critical assemblies which had uranium enrichments of 92.6% or higher in the uranium-235 isotope. The experiments were chosen so that a large variety of geometries and of neutron energy spectra were covered. Problems, calculating the k/sub eff/ of systems with high-uranium-concentration uranyl nitrate solution that were minimally reflected or unreflected, resulted in the separate examination of five cases.

  2. Examining the Use of Video Study Groups for Developing Literacy Pedagogical Content Knowledge of Critical Elements of Strategy Instruction with Elementary Teachers

    ERIC Educational Resources Information Center

    Shanahan, Lynn E.; Tochelli, Andrea L.

    2014-01-01

    This collective case study explored what nine elementary teachers' video study group discussions revealed about their understanding of pedagogical content knowledge for an explicit reading strategy instruction framework, Critical Elements of Strategy Instruction (CESI). Qualitative methods were used to inductively and deductively analyze…

  3. The application of heterogeneous cluster grouping to reflective writing for medical humanities literature study to enhance students' empathy, critical thinking, and reflective writing.

    PubMed

    Liao, Hung-Chang; Wang, Ya-Huei

    2016-09-02

    To facilitate interdisciplinary collaboration and to make connections between patients' diseases and their social/cultural contexts, the study examined whether the use of heterogeneous cluster grouping in reflective writing for medical humanities literature acquisition could have positive effects on medical university students in terms of empathy, critical thinking, and reflective writing. A 15-week quasi-experimental design was conducted to investigate the learning outcomes. After conducting cluster algorithms, heterogeneous learning clusters (experimental group; n = 43) and non-heterogeneous learning clusters (control group; n = 43) were derived for a medical humanities literature study. Before and after the intervention, an Empathy Scale in Patient Care (ES-PC), a critical thinking disposition assessment (CTDA-R), and a reflective writing test were administered to both groups. The findings showed that on the empathy scale, significant differences in the "behavioral empathy," "affective empathy," and overall sections existed between the post-test mean scores of the experimental group and those of the control group, but such differences did not exist in "intelligent empathy." Regarding critical thinking, there were significant differences in "systematicity and analyticity," "skepticism and well-informed," "maturity and skepticism," and overall sections. As for reflective writing, significant differences existed in "ideas," "voice and point of view," "critical thinking and representation," "depth of reflection on personal growth," and overall sections, but not in "focus and context structure" and "language and conventions." This study outlined an alternative for using heterogeneous cluster grouping in reflective writing about medical humanities literature to facilitate interdisciplinary cooperation to provide more humanizing medical care.

  4. USTUR case 0259 whole body donation: a comprehensive test of the current ICRP models for the behavior of inhaled 238PuO2 ceramic particles. U.S. Transuranium and Uranium Registries.

    PubMed

    James, A C; Filipy, R E; Russell, J J; McInroy, J F

    2003-01-01

    An analysis of 238Pu in the whole body donation to the U.S. Transuranium and Uranium Registries (USTUR) is presented. This donor accidentally inhaled an unusual physical form of plutonium, predominantly the 238Pu isotope in the form of a highly insoluble ceramic. Along with six other workers accidentally exposed at the same time, this donor excreted little or no 238Pu in his urine for several months. Subsequently, however, and, with no further intakes, the urinary excretion of 238Pu by all of these workers increased progressively. Such a pattern of increasing urinary excretion of plutonium resulting from a single acute inhalation was unknown at the time. The subject of this study provided a unique opportunity to analyze not only the pattern of urinary excretion for 17 y following this unusual intake but also the complete distribution of 238Pu in his donated body tissues and skeleton at death. Radiochemical analyses of tissues from this whole body donation were used to perform critical tests of the applicability and accuracy of the respiratory tract model and the systemic biokinetic models for plutonium currently recommended by the International Commission on Radiological Protection. The respiratory tract model was applied to analyze the donor's long-term urinary excretion pattern. The facility provided by this model to represent progressive transformation of insoluble particles in the lungs into a more soluble form, applied in conjunction with the systemic biokinetic model, predicted the total amount of 238Pu measured in the donor's body to within 17% accuracy. The measured division of 238Pu between the donor's lungs and systemic organs was predicted to within 10%. Small adjustments to several rate constants in these models provided precise predictions of the absolute amounts of 238Pu in the lungs, thoracic lymph nodes, liver, red bone marrow, skeleton (including the distribution of 238Pu between trabecular and cortical bone matrices derived from the radiochemical

  5. Group Dynamics as a Critical Component of Successful Space Exploration: Conceptual Theory and Insights from the Biosphere 2 Closure Experiment

    NASA Astrophysics Data System (ADS)

    Nelson, Mark; Allen, John P.

    As space exploration and eventually habitation achieves longer durations, successfully managing group dynamics of small, physically isolated groups will become vital. The paper summarizes important underlying research and conceptual theory and how these manifested in a well-documented example: the closure experiments of Biosphere 2. Key research breakthroughs in discerning the operation of small human groups comes from the pioneering work of W.R. Bion. He discovered two competing modalities of behavior. The first is the “task-oriented” or work group governed by shared acceptance of goals, reality-thinking in relation to time, resources and rational, and intelligent management of challenges presented. The opposing, usually unconscious, modality is what Bion called the “basic-assumption” group and alternates between three “group animal” groups: dependency/kill the leader; fight/flight and pairing. If not dealt with, these dynamics work to undermine and defeat the conscious task group’s goal achievement. The paper discusses crew training and selection, various approaches to structuring the work and hierarchy of the group, the importance of contact with a larger population through electronic communication and dealing with the “us-them” syndrome frequently observed between crew and Mission Control. The experience of the first two year closure of Biosphere 2 is drawn on in new ways to illustrate vicissitudes and management of group dynamics especially as both the inside team of biospherians and key members of Mission Control had training in working with group dynamics. Insights from that experience may help mission planning so that future groups in space cope successfully with inherent group dynamics challenges that arise.

  6. Global and regional trends in the nutritional status of young people: a critical and neglected age group.

    PubMed

    Akseer, Nadia; Al-Gashm, Sara; Mehta, Seema; Mokdad, Ali; Bhutta, Zulfiqar A

    2017-04-01

    Adolescence and emerging adulthood form a critical time period for the achievement of optimal health and nutrition across all stages of the life course. We undertook a review of published literature and global data repositories for information on nutrition levels, trends, and patterns among young people aged 10-24 years from January 1, 2016 to September 20, 2016. We describe patterns for both males and females at the global level and for geographic regions for the period covering 1990-2015. The results of this study paint a less than ideal picture of current young people's nutrition, suggesting dual burdens of underweight and high body-mass index in many countries and variable improvements in micronutrient deficiencies across geographical regions. Poor diet diversity and lack of nutrient-dense food, high risk for metabolic syndrome, and sedentary lifestyles also characterize this population. The need for objective, comparable, and high-quality data is also recognized for further study in this area. As the global community works toward supporting and scaling up health gains in the sustainable development goal era, realizing the critical role of young people is essential. Investing in young people's nutrition is critical to making strides in improving the overall health and well-being of all populations. © 2017 New York Academy of Sciences.

  7. Imaging Critical Zone Using High Frequency Rayleigh Wave Group Velocity Measurements Extracted from Ambient Seismic Fields Gathered With 2400 Seismic Nodes in Southeastern Wyoming.

    NASA Astrophysics Data System (ADS)

    Keifer, I. S.; Dueker, K. G.

    2016-12-01

    In an effort to characterize critical zone development in varying regions, seismologist conduct seismic surveys to assist in the realization of critical zone properties e.g. porosity and regolith thickness. A limitation of traditional critical zone seismology is that data is normally collected along lines, to generate two dimensional transects of the subsurface seismic velocity, even though the critical zone structure is 3D. Hence, we deployed six seismic 2D arrays in southeastern Wyoming to gather ambient seismic fields so that 3D shear velocity models could be produced. The arrays were made up of nominally 400 seismic stations arranged in a 200-meter square grid layout. Each array produced a half Terabyte data volume, so a premium was placed on computational efficiency throughout this study, to handle the roughly 65 billion samples recorded by each array. The ambient fields were cross-correlated on the Yellowstone Super-Computer using the pSIN code (Chen et al., 2016), which decreased correlation run times by a factor of 300 with respect to workstation computers. Group delay times extracted from cross-correlations using 8 Hz frequency bands from 10 Hz to 100 Hz show frequency dispersion at sites with shallow regolith underlain by granite bedrock. Dimensionally, the group velocity map inversion is overdetermined, even after extensive culling of spurious group delay times. Model Resolution matrices for our six arrays show values > 0.7 for most of the modal domain, approaching unity at the center of the model domain; we are then confident that we have an adequate number of rays covering our array space, and should experience minimal smearing of our resultant model due to application of inverse solution on the data. After inverting for the group velocity maps, a second inversion is performed of the group velocity maps for the 3D shear velocity model. This inversion is underdetermined and a second order Tikhonov regularization is used to obtain stable inverse images

  8. [Hemodynamic monitoring in the critically patient. Recomendations of the Cardiological Intensive Care and CPR Working Group of the Spanish Society of Intensive Care and Coronary Units].

    PubMed

    Ochagavía, A; Baigorri, F; Mesquida, J; Ayuela, J M; Ferrándiz, A; García, X; Monge, M I; Mateu, L; Sabatier, C; Clau-Terré, F; Vicho, R; Zapata, L; Maynar, J; Gil, A

    2014-04-01

    Hemodynamic monitoring offers valuable information on cardiovascular performance in the critically ill, and has become a fundamental tool in the diagnostic approach and in the therapy guidance of those patients presenting with tissue hypoperfusion. From introduction of the pulmonary artery catheter to the latest less invasive technologies, hemodynamic monitoring has been surrounded by many questions regarding its usefulness and its ultimate impact on patient prognosis. The Cardiological Intensive Care and CPR Working Group (GTCIC-RCP) of the Spanish Society of Intensive Care and Coronary Units (SEMICYUC) has recently impulsed the development of an updating series in hemodynamic monitoring. Now, a final series of recommendations are presented in order to analyze essential issues in hemodynamics, with the purpose of becoming a useful tool for residents and critical care practitioners involved in the daily management of critically ill patients. Copyright © 2013 Elsevier España, S.L. and SEMICYUC. All rights reserved.

  9. Intensive versus standard physical rehabilitation therapy in the critically ill (EPICC): a multicentre, parallel-group, randomised controlled trial.

    PubMed

    Wright, Stephen E; Thomas, Kirsty; Watson, Gillian; Baker, Catherine; Bryant, Andrew; Chadwick, Thomas J; Shen, Jing; Wood, Ruth; Wilkinson, Jennifer; Mansfield, Leigh; Stafford, Victoria; Wade, Clare; Furneval, Julie; Henderson, Andrea; Hugill, Keith; Howard, Philip; Roy, Alistair; Bonner, Stephen; Baudouin, Simon

    2017-08-05

    Early physical rehabilitation in the intensive care unit (ICU) has been shown to improve short-term clinical outcomes but long-term benefit has not been proven and the optimum intensity of rehabilitation is not known. We conducted a randomised, parallel-group, allocation-concealed, assessor-blinded, controlled trial in patients who had received at least 48 hours of invasive or non-invasive ventilation. Participants were randomised in a 1:1 ratio, stratified by admitting ICU, admission type and level of independence. The intervention group had a target of 90 min physical rehabilitation per day, the control group a target of 30 min per day (both Monday to Friday). The primary outcome was the Physical Component Summary (PCS) measure of SF-36 at 6 months. We recruited 308 participants over 34 months: 150 assigned to the intervention and 158 to the control group. The intervention group received a median (IQR) of 161 (67-273) min of physical rehabilitation on ICU compared with 86 (31-139) min in the control group. At 6 months, 62 participants in the intervention group and 54 participants in the control group contributed primary outcome data. In the intervention group, 43 had died, 11 had withdrawn and 34 were lost to follow-up, while in the control group, 56 had died, 5 had withdrawn and 43 were lost to follow-up. There was no difference in the primary outcome at 6 months, mean (SD) PCS 37 (12.2) in the intervention group and 37 (11.3) in the control group. In this study, ICU-based physical rehabilitation did not appear to improve physical outcomes at 6 months compared with standard physical rehabilitation. ISRCTN 20436833. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  10. [Contributions of the thought of Didier Fassin to a critical analysis of healthcare policies for vulnerable population groups].

    PubMed

    Weintraub, Ana Cecília Andrade de Moraes; Costa, Maria da Penha Vasconcellos

    2013-01-01

    This is a reflection on the contributions made over the last 14 years by Didier Fassin, in his analysis of issues raised by the phenomenon of migration in contemporary times, especially in France. He regards it as fundamental to comprehend the political uses behind the advent of 'humanitarian reason' and the 'empire of trauma', which underpin society today, in order to understand the suffering caused by large and small crises and the way social forces related to them act. Drawing on Foucault's concepts of biopolitics and biopower, Fassin makes a critical appraisal of the aid and assistance provided for society's 'unwanted' and their lifestyles, marked by social inclusion and exclusion via the body and trauma.

  11. Teaching about Controversial Groups in Public Schools: Critical Multiculturalism and the Case of Muslims since September 11

    ERIC Educational Resources Information Center

    Jackson, Elizabeth Jeanne

    2009-01-01

    This study explores some major challenges involved in teaching about controversial groups in U.S. public schools, discussing as an example education about Muslims since September 11, 2001 (9/11), and the need for students to develop accurate and balanced perceptions of others in a democratic society. In the first chapter, the two prominent…

  12. An Analysis of a Counselor Education Program with a Critical Examination of Practicum and Group Experiences. Final Report.

    ERIC Educational Resources Information Center

    Anderson, Sharon

    Part I of this two-part study compared prospective counselors' scores on selected measuring instruments at the beginning of their course work and practicum experience, and later at the end of their practicum experience. Part II examined the effect of a course in group counseling techniques on prospective counselors' self concepts, self images,…

  13. Teaching about Controversial Groups in Public Schools: Critical Multiculturalism and the Case of Muslims since September 11

    ERIC Educational Resources Information Center

    Jackson, Elizabeth Jeanne

    2009-01-01

    This study explores some major challenges involved in teaching about controversial groups in U.S. public schools, discussing as an example education about Muslims since September 11, 2001 (9/11), and the need for students to develop accurate and balanced perceptions of others in a democratic society. In the first chapter, the two prominent…

  14. Absorbed organ and effective doses from digital intra-oral and panoramic radiography applying the ICRP 103 recommendations for effective dose estimations.

    PubMed

    Granlund, Christina; Thilander-Klang, Anne; Ylhan, Betȕl; Lofthag-Hansen, Sara; Ekestubbe, Annika

    2016-10-01

    During dental radiography, the salivary and thyroid glands are at radiation risk. In 2007, the International Commission on Radiological Protection (ICRP) updated the methodology for determining the effective dose, and the salivary glands were assigned tissue-specific weighting factors for the first time. The aims of this study were to determine the absorbed dose to the organs and to calculate, applying the ICRP publication 103 tissue-weighting factors, the effective doses delivered during digital intraoral and panoramic radiography. Thermoluminescent dosemeter measurements were performed on an anthropomorphic head and neck phantom. The organ-absorbed doses were measured at 30 locations, representing different radiosensitive organs in the head and neck, and the effective dose was calculated according to the ICRP recommendations. The salivary glands and the oral mucosa received the highest absorbed doses from both intraoral and panoramic radiography. The effective dose from a full-mouth intraoral examination was 15 μSv and for panoramic radiography, the effective dose was in the range of 19-75 μSv, depending on the panoramic equipment used. The effective dose from a full-mouth intraoral examination is lower and that from panoramic radiography is higher than previously reported. Clinicians should be aware of the higher effective dose delivered during panoramic radiography and the risk-benefit profile of this technique must be assessed for the individual patient. The effective dose of radiation from panoramic radiography is higher than previously reported and there is large variability in the delivered radiation dosage among the different types of equipment used.

  15. Absorbed organ and effective doses from digital intra-oral and panoramic radiography applying the ICRP 103 recommendations for effective dose estimations

    PubMed Central

    Thilander-Klang, Anne; Ylhan, Betȕl; Lofthag-Hansen, Sara; Ekestubbe, Annika

    2016-01-01

    Objective: During dental radiography, the salivary and thyroid glands are at radiation risk. In 2007, the International Commission on Radiological Protection (ICRP) updated the methodology for determining the effective dose, and the salivary glands were assigned tissue-specific weighting factors for the first time. The aims of this study were to determine the absorbed dose to the organs and to calculate, applying the ICRP publication 103 tissue-weighting factors, the effective doses delivered during digital intraoral and panoramic radiography. Methods: Thermoluminescent dosemeter measurements were performed on an anthropomorphic head and neck phantom. The organ-absorbed doses were measured at 30 locations, representing different radiosensitive organs in the head and neck, and the effective dose was calculated according to the ICRP recommendations. Results: The salivary glands and the oral mucosa received the highest absorbed doses from both intraoral and panoramic radiography. The effective dose from a full-mouth intraoral examination was 15 μSv and for panoramic radiography, the effective dose was in the range of 19–75 μSv, depending on the panoramic equipment used. Conclusion: The effective dose from a full-mouth intraoral examination is lower and that from panoramic radiography is higher than previously reported. Clinicians should be aware of the higher effective dose delivered during panoramic radiography and the risk–benefit profile of this technique must be assessed for the individual patient. Advances in knowledge: The effective dose of radiation from panoramic radiography is higher than previously reported and there is large variability in the delivered radiation dosage among the different types of equipment used. PMID:27452261

  16. Five-year follow-up study on individual doses of Korean radiation workers based on ICRP 103 (2006-2010)

    NASA Astrophysics Data System (ADS)

    Lee, Jae-Seung; Ryu, Young-Hwan; Dong, Kyung-Rae; Goo, Eun-Hoe; Cho, Jae-Hwan; Lee, Hae-Kag; Kang, Seong-Jin; Choi, Eun-Jin; Chung, Woon-Kwan; Cha, Jang-Gyu

    2012-11-01

    This study examined individual doses of Korean radiation workers divided into deep and surface doses based on the dose limits recommended by the International Commission on Radiological Protection (ICRP) or ICRP 103 (approved on March 2007) for 5 years from 2006 to 2010. In addition, the exposure doses were compared according to occupation, departments and scale of the medical institutions (primary, secondary and tertiary) as well as between dental hospitals and hospitals, which is currently an issue, using 116,220 sets of data on the quarterly and yearly exposure doses of 5811 Korean radiation workers measured over a 5-year period (January 2006 to December 2010). For the mean exposure doses according to occupation, both deep and surface doses were higher in radiological technicians than in the other occupations and there was a significant difference between radiological technicians and others (researchers and assistants) (p<0.05). The results showed that none of the Korean radiation workers were exposed to radiation doses exceeding the maximum tolerant dose or 20 mSv/year recommended by the ICRP. When the mean exposure doses were compared according to the departments, both deep and surface doses were significantly higher (p<0.05) in the department of nuclear medicine than in the other departments (the department of biomedical engineering and the management team). For the mean exposure doses according to the scale of the medical institutions, the doses were highest in tertiary medical institutions followed in order by secondary and primary medical institutions (p<0.05). A comparison of the mean exposure doses in dental hospitals and hospitals revealed both deep and surface doses to be higher in hospitals than in dental hospitals (p<0.05). This study is considered to be used as basic data to establish a system for exposure dose management of radiation workers and more accurate studies on the radiation exposure are necessary in the future.

  17. Hp(3)/Φ conversion coefficients for neutrons: discussion on the basis of the new ICRP recommended limit for the eye lens.

    PubMed

    Ferrari, P; Gualdrini, G; Tanner, R; Fantuzzi, E

    2014-10-01

    The new recommendation issued by the International Commission on Radiological Protection (ICRP) introducing a 20-mSv annual dose limit for the eye lens stimulated an interesting debate among the radiation protection community. In the present work the problem of estimating Hp(3) for neutron realistic workplace spectra is treated, employing the recently published Hp(3)/Φ conversion coefficients with the aim of establishing a workplace-dependent relationship between Hp(10) and Hp(3). The results demonstrate that, whilst the two quantities can differ by less than 10 %, in general, Hp(10) cannot be considered a conservative estimate of Hp(3).

  18. Critical effect of the N2 amino group on structure, dynamics, and elasticity of DNA polypurine tracts.

    PubMed Central

    Lankas, Filip; Cheatham, Thomas E; Spacková, Nad'a; Hobza, Pavel; Langowski, Jörg; Sponer, Jirí

    2002-01-01

    Unrestrained 5-20-ns explicit-solvent molecular dynamics simulations using the Cornell et al. force field have been carried out for d[GCG(N)11GCG]2 (N, purine base) considering guanine*cytosine (G*C), adenine*thymine (A*T), inosine*5-methyl-cytosine (I*mC), and 2-amino-adenine*thymine (D*T) basepairs. The simulations unambiguously show that the structure and elasticity of N-tracts is primarily determined by the presence of the amino group in the minor groove. Simulated A-, I-, and AI-tracts show almost identical structures, with high propeller twist and minor groove narrowing. G- and D-tracts have small propeller twisting and are partly shifted toward the A-form. The elastic properties also differ between the two groups. The sequence-dependent electrostatic component of base stacking seems to play a minor role. Our conclusions are entirely consistent with available experimental data. Nevertheless, the propeller twist and helical twist in the simulated A-tract appear to be underestimated compared to crystallographic studies. To obtain further insight into the possible force field deficiencies, additional multiple simulations have been made for d(A)10, systematically comparing four major force fields currently used in DNA simulations and utilizing B and A-DNA forms as the starting structure. This comparison shows that the conclusions of the present work are not influenced by the force field choice. PMID:11964246

  19. Critical issues with the in vivo comet assay: A report of the comet assay working group in the 6th International Workshop on Genotoxicity Testing (IWGT).

    PubMed

    Speit, Günter; Kojima, Hajime; Burlinson, Brian; Collins, Andrew R; Kasper, Peter; Plappert-Helbig, Ulla; Uno, Yoshifumi; Vasquez, Marie; Beevers, Carol; De Boeck, Marlies; Escobar, Patricia A; Kitamoto, Sachiko; Pant, Kamala; Pfuhler, Stefan; Tanaka, Jin; Levy, Dan D

    2015-05-01

    As a part of the 6th IWGT, an expert working group on the comet assay evaluated critical topics related to the use of the in vivo comet assay in regulatory genotoxicity testing. The areas covered were: identification of the domain of applicability and regulatory acceptance, identification of critical parameters of the protocol and attempts to standardize the assay, experience with combination and integration with other in vivo studies, demonstration of laboratory proficiency, sensitivity and power of the protocol used, use of different tissues, freezing of samples, and choice of appropriate measures of cytotoxicity. The standard protocol detects various types of DNA lesions but it does not detect all types of DNA damage. Modifications of the standard protocol may be used to detect additional types of specific DNA damage (e.g., cross-links, bulky adducts, oxidized bases). In addition, the working group identified critical parameters that should be carefully controlled and described in detail in every published study protocol. In vivo comet assay results are more reliable if they were obtained in laboratories that have demonstrated proficiency. This includes demonstration of adequate response to vehicle controls and an adequate response to a positive control for each tissue being examined. There was a general agreement that freezing of samples is an option but more data are needed in order to establish generally accepted protocols. With regard to tissue toxicity, the working group concluded that cytotoxicity could be a confounder of comet results. It is recommended to look at multiple parameters such as histopathological observations, organ-specific clinical chemistry as well as indicators of tissue inflammation to decide whether compound-specific toxicity might influence the result. The expert working group concluded that the alkaline in vivo comet assay is a mature test for the evaluation of genotoxicity and can be recommended to regulatory agencies for use.

  20. Functional feeding groups of aquatic insect families in Latin America: a critical analysis and review of existing literature.

    PubMed

    Ramírez, Alonso; Gutiérrez-Fonseca, Pablo E

    2014-04-01

    Aquatic macroinvertebrates are involved in numerous processes within aquatic ecosystems. They often have important effects on ecosystem processes such as primary production (via grazing), detritus breakdown, and nutrient mineralization and downstream spiraling. The functional feeding groups (FFG) classification was developed as a tool to facilitate the incorporation of macroinvertebrates in studies of aquatic ecosystems. This classification has the advantage of combining morphological characteristics (e.g., mouth part specialization) and behavioral mechanisms (e.g., way of feeding) used by macroinvertebrates when consuming resources. Although recent efforts have greatly advanced our ability to identify aquatic macroinvertebrates, there is limited information on FFG assignment. Furthermore, there has been some variation in the use of the FFG classification, in part due to an emphasis on using gut content analysis to assign FFG, which is more appropriate for assigning trophic guilds. Thus, the main goals of this study are to (1) provide an overview of the value of using the FFG classification, (2) make an initial attempt to summarize available information on FFG for aquatic insects in Latin America, and (3) provide general guidelines on how to assign organisms to their FFGs. FFGs are intended to reflect the potential effects of organisms in their ecosystems and the way they consume resources. Groups include scrapers that consume resources that grow attached to the substrate by removing them with their mouth parts; shredders that cut or chew pieces of living or dead plant material, including all plant parts like leaves and wood; collectors-gatherers that use modified mouth parts to sieve or collect small particles (< 1 mm) accumulated on the stream bottom; filterers that have special adaptations to remove particles directly from the water column; and predators that consume other organisms using different strategies to capture them. In addition, we provide details on

  1. Risk factors for early-onset group B streptococcal sepsis: estimation of odds ratios by critical literature review.

    PubMed

    Benitz, W E; Gould, J B; Druzin, M L

    1999-06-01

    To identify and to establish the prevalence of ORs factors associated with increased risk for early-onset group B streptococcal (EOGBS) infection in neonates. streptococcal (EOGBS) infection in neonates. Literature review and reanalysis of published data. Risk factors for EOGBS infection include group B streptococcal (GBS)-positive vaginal culture at delivery (OR: 204), GBS-positive rectovaginal culture at 28 (OR: 9.64) or 36 weeks gestation (OR: 26. 7), vaginal Strep B OIA test positive at delivery (OR: 15.4), birth weight 18 hours (OR: 7.28), intrapartum fever >37.5 degrees C (OR: 4.05), intrapartum fever, PROM, or prematurity (OR: 9.74), intrapartum fever or PROM at term (OR: 11.5), chorioamnionitis (OR: 6.43). Chorioamnionitis is reported in most (88%) cases in which neonatal infection occurred despite intrapartum maternal antibiotic therapy. ORs could not be estimated for maternal GBS bacteriuria during pregnancy, with preterm premature rupture of membranes, or with a sibling or twin with invasive GBS disease, but these findings seem to be associated with a very high risk. Multiple gestation is not an independent risk factor for GBS infection. h Mothers with GBS bacteriuria during pregnancy, with another child with GBS disease, or with chorioamnionitis should receive empirical intrapartum antibiotic treatment. Their infants should have complete diagnostic evaluations and receive empirical treatment until infection is excluded by observation and negative cultures because of their particularly high risk for EOGBS infection. Either screening with cultures at 28 weeks gestation or identification of clinical risk factors, ie, PROM, intrapartum fever, or prematurity, may identify parturients whose infants include 65% of those with EOGBS infection. Intrapartum screening using the Strep B OIA rapid test identifies more at-risk infants (75

  2. c-Jun kinase is a critical signaling molecule in a neonatal model of group B streptococcal sepsis.

    PubMed

    Kenzel, Sybille; Mancuso, Guiseppe; Malley, Richard; Teti, Guiseppe; Golenbock, Douglas T; Henneke, Philipp

    2006-03-01

    Group B streptococcus (GBS) is the major cause of sepsis in newborn infants. In vitro, inactivated GBS stimulates macrophages to produce inflammatory proteins via the TLR adapter protein MyD88. Furthermore, inflammatory cytokine release in response to GBS greatly exceeds that following stimulation with pneumococci. In this study, we attempted to unravel signaling events that are involved in GBS-, but not Streptococcus pneumoniae-stimulated phagocytes to identify molecular targets for adjunctive sepsis therapy. We found that inactivated GBS and S. pneumoniae differed in the activation of the MAPK JNK, but not IkappaB kinase. Furthermore, JNK was essential for the transcriptional activation of inflammatory cytokine genes in response to GBS. Inhibition of JNK by the anthrapyrazolone SP600125 abrogated GBS-induced cytokine formation via an AP-1- and NF-kappaB-dependent mechanism without impairing antibacterial properties such as phagocytosis of GBS and the formation of intracellular oxidative species. In contrast, inhibition of the MAPK p38 impaired both antibacterial processes. In a neonatal mouse model of GBS sepsis SP600125 inhibited the inflammatory response and improved survival. In conclusion, JNK plays a major role in the inflammatory, but not in the direct antibacterial response to inactivated GBS, and may thus serve as a rational target for an adjunctive GBS sepsis therapy.

  3. Histo-Blood Group Antigen Presentation Is Critical for Binding of Norovirus VLP to Glycosphingolipids in Model Membranes.

    PubMed

    Nasir, Waqas; Frank, Martin; Kunze, Angelika; Bally, Marta; Parra, Francisco; Nyholm, Per-Georg; Höök, Fredrik; Larson, Göran

    2017-03-27

    Virus entry depends on biomolecular recognition at the surface of cell membranes. In the case of glycolipid receptors, these events are expected to be influenced by how the glycan epitope close to the membrane is presented to the virus. This presentation of membrane-associated glycans is more restricted than that of glycans in solution, particularly because of orientational constraints imposed on the glycolipid through its lateral interactions with other membrane lipids and proteins. We have developed and employed a total internal reflection fluorescence microscopy-based binding assay and a scheme for molecular dynamics (MD) membrane simulations to investigate the consequences of various glycan presentation effects. The system studied was histo-blood group antigen (HBGA) epitopes of membrane-bound glycosphingolipids (GSLs) derived from small intestinal epithelium of humans (type 1 chain) and dogs (type 2 chain) interacting with GII.4 norovirus-like particles. Our experimental results showed strong binding to all lipid-linked type 1 chain HBGAs but no or only weak binding to the corresponding type 2 chain HBGAs. This is in contrast to results derived from STD experiments with free HBGAs in solution where binding was observed for Lewis x. The MD data suggest that the strong binding to type 1 chain glycolipids was due to the well-exposed (1,2)-linked α-l-Fucp and (1,4)-linked α-l-Fucp residues, while the weaker binding or lack of binding to type 2 chain HBGAs was due to the very restricted accessibility of the (1,3)-linked α-l-Fucp residue when the glycolipid is embedded in a phospholipid membrane. Our results not only contribute to a general understanding of protein-carbohydrate interactions on model membrane surfaces, particularly in the context of virus binding, but also suggest a possible role of human intestinal GSLs as potential receptors for norovirus uptake.

  4. Development of a computer code to calculate the distribution of radionuclides within the human body by the biokinetic models of the ICRP.

    PubMed

    Matsumoto, Masaki; Yamanaka, Tsuneyasu; Hayakawa, Nobuhiro; Iwai, Satoshi; Sugiura, Nobuyuki

    2015-03-01

    This paper describes the Basic Radionuclide vAlue for Internal Dosimetry (BRAID) code, which was developed to calculate the time-dependent activity distribution in each organ and tissue characterised by the biokinetic compartmental models provided by the International Commission on Radiological Protection (ICRP). Translocation from one compartment to the next is taken to be governed by first-order kinetics, which is formulated by the first-order differential equations. In the source program of this code, the conservation equations are solved for the mass balance that describes the transfer of a radionuclide between compartments. This code is applicable to the evaluation of the radioactivity of nuclides in an organ or tissue without modification of the source program. It is also possible to handle easily the cases of the revision of the biokinetic model or the application of a uniquely defined model by a user, because this code is designed so that all information on the biokinetic model structure is imported from an input file. The sample calculations are performed with the ICRP model, and the results are compared with the analytic solutions using simple models. It is suggested that this code provides sufficient result for the dose estimation and interpretation of monitoring data.

  5. Photon and neutron fluence-to-kerma conversion factors for ICRP-1975 reference man using improved elemental compositions for bone and marrow of the skeleton

    SciTech Connect

    Kerr, G.D.

    1982-11-01

    A twelve-element approximation of the total-body, soft-tissue and skeletal components of ICRP-1975 Reference Man is used to investigate particle fluence-to-kerma conversion factors for photons with energies between 1 keV and 20 MeV and neutrons with energies between 0.0253 eV and 20 MeV. Several recent ICRP revisions to the elemental composition of Reference Man, which have not been included in other kerma-factor calculations, are taken into account. This work suggests some additional revisions to the major-element content (i.e., H, C, N, and O) and to the mineral and trace-element content (i.e., Na, Mg, P, S, Cl, K, Ca, and Fe) of various total-body, soft-tissue, and skeletal components of Reference Man. The revisions to the bone and red marrow of the skeleton offer significant new refinements in red-bone-marrow dosimetry.

  6. Nonperturbative functional renormalization-group approach to transport in the vicinity of a (2 +1 ) -dimensional O(N )-symmetric quantum critical point

    NASA Astrophysics Data System (ADS)

    Rose, F.; Dupuis, N.

    2017-01-01

    Using a nonperturbative functional renormalization-group approach to the two-dimensional quantum O (N ) model, we compute the low-frequency limit ω →0 of the zero-temperature conductivity in the vicinity of the quantum critical point. Our results are obtained from a derivative expansion to second order of a scale-dependent effective action in the presence of an external (i.e., nondynamical) non-Abelian gauge field. While in the disordered phase the conductivity tensor σ (ω ) is diagonal, in the ordered phase it is defined, when N ≥3 , by two independent elements, σA(ω ) and σB(ω ) , respectively associated to SO (N ) rotations which do and do not change the direction of the order parameter. For N =2 , the conductivity in the ordered phase reduces to a single component σA(ω ) . We show that limω→0σ (ω ,δ ) σA(ω ,-δ ) /σq2 is a universal number, which we compute as a function of N (δ measures the distance to the quantum critical point, q is the charge, and σq=q2/h the quantum of conductance). On the other hand we argue that the ratio σB(ω →0 ) /σq is universal in the whole ordered phase, independent of N and, when N →∞ , equal to the universal conductivity σ*/σq at the quantum critical point.

  7. GIS-based identification of areas that have resource potential for critical minerals in six Selected Groups of Deposit Types in Alaska

    USGS Publications Warehouse

    Karl, Susan M.; Jones, III, James V.; Hayes, Timothy S.

    2016-11-16

    Alaska has considerable potential for undiscovered mineral resources. This report evaluates potential for undiscovered critical minerals in Alaska. Critical minerals are those for which the United States imports more than half of its total supply and which are largely derived from nations that cannot be considered reliable trading partners. In this report, estimated resource potential and certainty for the state of Alaska are analyzed and mapped for the following six selected mineral deposit groups that may contain one or more critical minerals: (1) rare earth elements-thorium-yttrium-niobium(-uranium-zirconium) [REE-Th-Y-Nb(-U-Zr)] deposits associated with peralkaline to carbonatitic igneous intrusive rocks; (2) placer and paleoplacer gold (Au) deposits that in some places might also produce platinum group elements (PGE), chromium (Cr), tin (Sn), tungsten (W), silver (Ag), or titanium (Ti); (3) platinum group elements(-cobalt-chromium-nickel-titanium-vanadium) [PGE(-Co-Cr-Ni-Ti-V)] deposits associated with mafic to ultramafic intrusive rocks; (4) carbonate-hosted copper(-cobalt-silver-germanium-gallium) [Cu(-Co-Ag-Ge-Ga)] deposits; (5) sandstone-hosted uranium(-vanadium-copper) [U(-V-Cu)] deposits; and (6) tin-tungsten-molybdenum(-tantalum-indium-fluorspar) [Sn-W-Mo(-Ta-In-fluorspar)] deposits associated with specialized granites.This study used a data-driven, geographic information system (GIS)-implemented method to identify areas that have mineral resource potential in Alaska. This method systematically and simultaneously analyzes geoscience data from multiple geospatially referenced datasets and uses individual subwatersheds (12-digit hydrologic units) as the spatial unit of classification. The final map output uses a red, yellow, green, and gray color scheme to portray estimated relative potential (High, Medium, Low, Unknown) for each of the six groups of mineral deposit types, and it indicates the relative certainty (High, Medium, Low) of that estimate for

  8. Application of the ICRP/ICRU reference computational phantoms to internal dosimetry: calculation of specific absorbed fractions of energy for photons and electrons.

    PubMed

    Hadid, L; Desbrée, A; Schlattl, H; Franck, D; Blanchardon, E; Zankl, M

    2010-07-07

    The emission of radiation from a contaminated body region is connected with the dose received by radiosensitive tissue through the specific absorbed fractions (SAFs) of emitted energy, which is therefore an essential quantity for internal dose assessment. A set of SAFs were calculated using the new adult reference computational phantoms, released by the International Commission on Radiological Protection (ICRP) together with the International Commission on Radiation Units and Measurements (ICRU). Part of these results has been recently published in ICRP Publication 110 (2009 Adult reference computational phantoms (Oxford: Elsevier)). In this paper, we mainly discuss the results and also present them in numeric form. The emission of monoenergetic photons and electrons with energies ranging from 10 keV to 10 MeV was simulated for three source organs: lungs, thyroid and liver. SAFs were calculated for four target regions in the body: lungs, colon wall, breasts and stomach wall. For quality assurance purposes, the simulations were performed simultaneously at the Helmholtz Zentrum München (HMGU, Germany) and at the Institute for Radiological Protection and Nuclear Safety (IRSN, France), using the Monte Carlo transport codes EGSnrc and MCNPX, respectively. The comparison of results shows overall agreement for photons and high-energy electrons with differences lower than 8%. Nevertheless, significant differences were found for electrons at lower energy for distant source/target organ pairs. Finally, the results for photons were compared to the SAF values derived using mathematical phantoms. Significant variations that can amount to 200% were found. The main reason for these differences is the change of geometry in the more realistic voxel body models. For electrons, no SAFs have been computed with the mathematical phantoms; instead, approximate formulae have been used by both the Medical Internal Radiation Dose committee (MIRD) and the ICRP due to the limitations imposed

  9. Application of the ICRP/ICRU reference computational phantoms to internal dosimetry: calculation of specific absorbed fractions of energy for photons and electrons

    NASA Astrophysics Data System (ADS)

    Hadid, L.; Desbrée, A.; Schlattl, H.; Franck, D.; Blanchardon, E.; Zankl, M.

    2010-07-01

    The emission of radiation from a contaminated body region is connected with the dose received by radiosensitive tissue through the specific absorbed fractions (SAFs) of emitted energy, which is therefore an essential quantity for internal dose assessment. A set of SAFs were calculated using the new adult reference computational phantoms, released by the International Commission on Radiological Protection (ICRP) together with the International Commission on Radiation Units and Measurements (ICRU). Part of these results has been recently published in ICRP Publication 110 (2009 Adult reference computational phantoms (Oxford: Elsevier)). In this paper, we mainly discuss the results and also present them in numeric form. The emission of monoenergetic photons and electrons with energies ranging from 10 keV to 10 MeV was simulated for three source organs: lungs, thyroid and liver. SAFs were calculated for four target regions in the body: lungs, colon wall, breasts and stomach wall. For quality assurance purposes, the simulations were performed simultaneously at the Helmholtz Zentrum München (HMGU, Germany) and at the Institute for Radiological Protection and Nuclear Safety (IRSN, France), using the Monte Carlo transport codes EGSnrc and MCNPX, respectively. The comparison of results shows overall agreement for photons and high-energy electrons with differences lower than 8%. Nevertheless, significant differences were found for electrons at lower energy for distant source/target organ pairs. Finally, the results for photons were compared to the SAF values derived using mathematical phantoms. Significant variations that can amount to 200% were found. The main reason for these differences is the change of geometry in the more realistic voxel body models. For electrons, no SAFs have been computed with the mathematical phantoms; instead, approximate formulae have been used by both the Medical Internal Radiation Dose committee (MIRD) and the ICRP due to the limitations imposed

  10. Mass-flow error in the numerical renormalization-group method and the critical behavior of the sub-Ohmic spin-boson model

    NASA Astrophysics Data System (ADS)

    Vojta, Matthias; Bulla, Ralf; Güttge, Fabian; Anders, Frithjof

    2010-02-01

    We discuss a particular source of error in the numerical renormalization group (NRG) method for quantum impurity problems, which is related to a renormalization of impurity parameters due to the bath propagator. At any step of the NRG calculation, this renormalization is only partially taken into account, leading to systematic variation in the impurity parameters along the flow. This effect can cause qualitatively incorrect results when studying quantum-critical phenomena, as it leads to an implicit variation in the phase transition’s control parameter as function of the temperature and thus to an unphysical temperature dependence of the order-parameter mass. We demonstrate the mass-flow effect for bosonic impurity models with a power-law bath spectrum, J(ω)∝ωs , namely, the dissipative harmonic oscillator and the spin-boson model. We propose an extension of the NRG to correct the mass-flow error. Using this, we find unambiguous signatures of a Gaussian critical fixed point in the spin-boson model for s<1/2 , consistent with mean-field behavior as expected from quantum-to-classical mapping.

  11. Application of NCRP 156 Wound Model and ICRP 67 Systemic Plutonium Model for Analysis of Urine Data from Simulated Wounds in Nonhuman Primates.

    PubMed

    Poudel, Deepesh; Guilmette, Raymond A; Konzen, Kevin; Krage, Eric S; Brey, Richard R

    2016-07-01

    The predictions of the wound model described in NCRP Report No. 156, coupled with the systemic model described in ICRP 67, were compared with the actual urinary excretion data and wound retention data from nonhuman primates injected intramuscularly or subcutaneously with Pu(IV) citrate. The results indicated that the early behavior of Pu(IV) citrate in wounds can be adequately described by the default retention parameters for moderately retained radionuclides suggested by the report. The urinary excretion rates after 200 d post intake could not be described well by the parameters of any of the default wound models because of the differences in the systemic handling of plutonium by humans compared to nonhuman primates.

  12. Fluence-to-dose conversion coefficients based on the posture modification of Adult Male (AM) and Adult Female (AF) reference phantoms of ICRP 110

    NASA Astrophysics Data System (ADS)

    Galeano, D. C.; Santos, W. S.; Alves, M. C.; Souza, D. N.; Carvalho, A. B.

    2016-04-01

    The aim of this work was to modify the standing posture of the anthropomorphic reference phantoms of ICRP publication 110, AM (Adult Male) and AF (Adult Female), to the sitting posture. The change of posture was performed using the Visual Monte Carlo software (VMC) to rotate the thigh region of the phantoms and position it between the region of the leg and trunk. Scion Image software was used to reconstruct and smooth the knee and hip contours of the phantoms in a sitting posture. For 3D visualization of phantoms, the VolView software was used. In the change of postures, the organ and tissue masses were preserved. The MCNPX was used to calculate the equivalent and effective dose conversion coefficients (CCs) per fluence for photons for six irradiation geometries suggested by ICRP publication 110 (AP, PA, RLAT, LLAT, ROT and ISO) and energy range 0.010-10 MeV. The results were compared between the standing and sitting postures, for both sexes, in order to evaluate the differences of scattering and absorption of radiation for different postures. Significant differences in the CCs for equivalent dose were observed in the gonads, colon, prostate, urinary bladder and uterus, which are present in the pelvic region, and in organs distributed throughout the body, such as the lymphatic nodes, muscle, skeleton and skin, for the phantoms of both sexes. CCs for effective dose showed significant differences of up to 16% in the AP irradiation geometry, 27% in the PA irradiation geometry and 13% in the ROT irradiation geometry. These results demonstrate the importance of using phantoms in different postures in order to obtain more precise conversion coefficients for a given exposure scenario.

  13. Systems for grading the quality of evidence and the strength of recommendations I: Critical appraisal of existing approaches The GRADE Working Group

    PubMed Central

    Atkins, David; Eccles, Martin; Flottorp, Signe; Guyatt, Gordon H; Henry, David; Hill, Suzanne; Liberati, Alessandro; O'Connell, Dianne; Oxman, Andrew D; Phillips, Bob; Schünemann, Holger; Edejer, Tessa Tan-Torres; Vist, Gunn E; Williams, John W

    2004-01-01

    Background A number of approaches have been used to grade levels of evidence and the strength of recommendations. The use of many different approaches detracts from one of the main reasons for having explicit approaches: to concisely characterise and communicate this information so that it can easily be understood and thereby help people make well-informed decisions. Our objective was to critically appraise six prominent systems for grading levels of evidence and the strength of recommendations as a basis for agreeing on characteristics of a common, sensible approach to grading levels of evidence and the strength of recommendations. Methods Six prominent systems for grading levels of evidence and strength of recommendations were selected and someone familiar with each system prepared a description of each of these. Twelve assessors independently evaluated each system based on twelve criteria to assess the sensibility of the different approaches. Systems used by 51 organisations were compared with these six approaches. Results There was poor agreement about the sensibility of the six systems. Only one of the systems was suitable for all four types of questions we considered (effectiveness, harm, diagnosis and prognosis). None of the systems was considered usable for all of the target groups we considered (professionals, patients and policy makers). The raters found low reproducibility of judgements made using all six systems. Systems used by 51 organisations that sponsor clinical practice guidelines included a number of minor variations of the six systems that we critically appraised. Conclusions All of the currently used approaches to grading levels of evidence and the strength of recommendations have important shortcomings. PMID:15615589

  14. Trends in critical care beds and use among population groups and Medicare and Medicaid beneficiaries in the United States: 2000–2010

    PubMed Central

    Halpern, Neil A.; Goldman, Debra A.; Tan, Kay See; Pastores, Stephen M.

    2017-01-01

    Objectives To analyze patterns of critical care medicine (CCM) beds, use, and costs in acute care hospitals in the United States (US), and relate CCM beds and use to population shifts, age groups, and Medicare and Medicaid beneficiaries from 2000 to 2010. Design Retrospective study of data from the federal Healthcare Cost Report Information System, American Hospital Association and US Census Bureau. Setting Acute care US hospitals with intensive care beds. Measurements and Main Results From 2000 to 2010, US hospitals with CCM beds decreased by 17% (3,586 to 2,977), while the US population increased by 9.6% (282.2M to 309.3M). Although hospital beds decreased by 2.2% (655,785 to 641,395), CCM beds increased by 17.8% (88,235 to 103,900), a 20.4% increase in the CCM/hospital bed ratio (13.5% to 16.2%). There was a greater percentage increase in premature/neonatal (29%, 14,391 to 18,567) than in adult (15.9%, 71,978 to 83,417) or pediatric (2.7%, 1,866 to 1,916) CCM beds. Hospital occupancy rates increased by 10% (59% to 65%), while CCM occupancy rates were stable (range 65%–68%). CCM beds per 100,000 total population increased by 7.4% (31.3 to 33.6). The proportional use of CCM services by Medicare beneficiaries decreased by 17% (37.9% to 31.4%) whereas that by Medicaid rose by 18% (14.5% to 17.2%). Between 2000 and 2010, annual CCM costs nearly doubled (92.9%, $56 to $108 billion). In the same period, the proportion of CCM cost to the Gross Domestic Product (GDP) increased by 32.1% (0.54% to 0.72%, $10,285 to $14,964 trillion). Conclusions Critical care medicine use and costs in the US continue to rise. The increasing use of CCM by the premature/neonatal and Medicaid populations should be considered by healthcare policy makers, state agencies, and hospitals as they wrestle with critical care bed growth and the associated costs. PMID:27136721

  15. Comparative effectiveness of peripheral vascular intervention versus surgical bypass for critical limb ischemia in the Vascular Study Group of Greater New York.

    PubMed

    Meltzer, Andrew J; Sedrakyan, Art; Isaacs, Abby; Connolly, Peter H; Schneider, Darren B

    2016-11-01

    In this study, the effectiveness of peripheral vascular intervention (PVI) was compared with surgical bypass grafting (BPG) for critical limb ischemia (CLI) in the Vascular Study Group of Greater New York (VSGGNY). Patients undergoing BPG or PVI for CLI at VSGGNY centers (2011-2013) were included. The Society for Vascular Surgery objective performance goals for CLI were used to directly compare the safety and effectiveness of PVI and BPG. Propensity score matching was used for risk-adjusted comparisons of PVI with BPG. A total of 414 patients (268 PVI, 146 BPG) were treated for tissue loss (69%) or rest pain (31%). Patients undergoing PVI were more likely to have tissue loss (74.6% vs 57.5%; P < .001) and comorbidities such as diabetes (69.3% vs 57.5%; P = .02), heart failure (22% vs 13.7%; P = .04), and severe renal disease (13.1% vs 4.1%; P = .004). No significant differences were found between the groups across a panel of safety objective performance goals. In unadjusted analyses at 1 year, BPG was associated with higher rates of freedom from reintervention, amputation, or restenosis (90.4% vs 81.7%; P = .02) and freedom from reintervention or amputation (92.5% vs 85.8%, P = .045). After propensity score matching, PVI was associated with improved freedom from major adverse limb events and postoperative death at 1 year (95.6% vs 88.5%; P < .05). By unadjusted comparison, early reintervention and restenosis are more prevalent with PVI. However, risk-adjusted comparison underscores the safety and effectiveness of PVI in the treatment of CLI. Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

  16. [Clinical and hygienic substantiation of individual biocorrection for ecologically dependent conditions in the critical groups of the population of Ukrainian industrial areas].

    PubMed

    Beletskaya, E N; Onul, N M; Glavatskaya, V I; Antonova, E V; Golovkova, T A

    2014-01-01

    In the article there is considered the problem of pollution of the environment and human body with heavy metals, the effectiveness of individual biocorrection in critical groups of the population--pregnant women and children residing in technologically contaminated areas. In spite of the correspondence of the content of abiotic heavy metals to their MACs in the environment, the concentration of lead and cadmium in the internal environment of the organism in 1,6-15,4 times was found to exceed physiological norms that accompanied by a significant deficiency of essential trace elements. Similar situation has been proved to lead to a reduction in mental health and ability to learn in children, as well as to the various complications in pregnancy. The obtained results served as the scientific substantiation of the feasibility of biocorrection of the trace element imbalance ecological dependent states in the population of the industrial region. The proved high clinical effectiveness of this hygienic biocorrection is a scientific justification for widespread introduction of pectin preparations for health promotion, prevention of ecologically dependent states and increasing the adaptive capacity of the organism.

  17. Critical Dose of Internal Organs Internal Exposure - 13471

    SciTech Connect

    Grigoryan, G.; Amirjanyan, A.; Grigoryan, N.

    2013-07-01

    The health threat posed by radionuclides has stimulated increased efforts to developed characterization on the biological behavior of radionuclides in humans in all ages. In an effort motivated largely by the Chernobyl nuclear accident, the International Commission on Radiological Protection (ICRP) is assembling a set of age specific biokinetic models for environmentally important radioelements. Radioactive substances in the air, mainly through the respiratory system and digestive tract, is inside the body. Radioactive substances are unevenly distributed in various organs and tissues. Therefore, the degree of damage will depend not only on the dose of radiation have but also on the critical organ, which is the most accumulation of radioactive substances, which leads to the defeat of the entire human body. The main objective of radiation protection, to avoid exceeding the maximum permissible doses of external and internal exposure of a person to prevent the physical and genetic damage people. The maximum tolerated dose (MTD) of radiation is called a dose of radiation a person in uniform getting her for 50 years does not cause changes in the health of the exposed individual and his progeny. The following classification of critical organs, depending on the category of exposure on their degree of sensitivity to radiation: First group: the whole body, gonads and red bone marrow; Second group: muscle, fat, liver, kidney, spleen, gastrointestinal tract, lungs and lens of the eye; The third group: bone, thyroid and skin; Fourth group: the hands, forearms, feet. MTD exposure whole body, gonads and bone marrow represent the maximum exposures (5 rem per year) experienced by people in their normal activities. The purpose of this article is intended dose received from various internal organs of the radionuclides that may enter the body by inhalation, and gastrointestinal tract. The biokinetic model describes the time dependent distribution and excretion of different

  18. [GEIPC-SEIMC (Study Group for Infections in the Critically Ill Patient of the Spanish Society for Infectious Diseases and Clinical Microbiology) and GTEI-SEMICYUC ( Working Group on Infectious Diseases of the Spanish Society of Intensive Medicine, Critical Care, and Coronary Units) recommendations for antibiotic treatment of gram-positive cocci infections in the critical patient].

    PubMed

    Astigarraga, P M Olaechea; Montero, J Garnacho; Cerrato, S Grau; Colomo, O Rodríguez; Martínez, M Palomar; Crespo, R Zaragoza; García-Paredes, P Muñoz; Cerdá, E Cerdá; Lerma, F Alvarez

    2007-01-01

    In recent years, an increment of infections caused by gram-positive cocci has been documented in nosocomial and hospital-acquired-infections. In diverse countries, a rapid development of resistance to common antibiotics against gram-positive cocci has been observed. This situation is exceptional in Spain but our country might be affected in the near future. New antimicrobials active against these multi-drug resistant pathogens are nowadays available. It is essential to improve our current knowledge about pharmacokinetic properties of traditional and new antimicrobials to maximize its effectiveness and to minimize toxicity. These issues are even more important in critically ill patients because inadequate empirical therapy is associated with therapeutic failure and a poor outcome. Experts representing two scientific societies (Grupo de estudio de Infecciones en el Paciente Crítico de la SEIMC and Grupo de trabajo de Enfermedades Infecciosas de la SEMICYUC) have elaborated a consensus document based on the current scientific evidence to summarize recommendations for the treatment of serious infections caused by gram-positive cocci in critically ill patients.

  19. Dose estimation for astronauts using dose conversion coefficients calculated with the PHITS code and the ICRP/ICRU adult reference computational phantoms.

    PubMed

    Sato, Tatsuhiko; Endo, Akira; Sihver, Lembit; Niita, Koji

    2011-03-01

    Absorbed-dose and dose-equivalent rates for astronauts were estimated by multiplying fluence-to-dose conversion coefficients in the units of Gy.cm(2) and Sv.cm(2), respectively, and cosmic-ray fluxes around spacecrafts in the unit of cm(-2) s(-1). The dose conversion coefficients employed in the calculation were evaluated using the general-purpose particle and heavy ion transport code system PHITS coupled to the male and female adult reference computational phantoms, which were released as a common ICRP/ICRU publication. The cosmic-ray fluxes inside and near to spacecrafts were also calculated by PHITS, using simplified geometries. The accuracy of the obtained absorbed-dose and dose-equivalent rates was verified by various experimental data measured both inside and outside spacecrafts. The calculations quantitatively show that the effective doses for astronauts are significantly greater than their corresponding effective dose equivalents, because of the numerical incompatibility between the radiation quality factors and the radiation weighting factors. These results demonstrate the usefulness of dose conversion coefficients in space dosimetry. © Springer-Verlag 2010

  20. Assessment of uncertainties in the lung activity measurement of low-energy photon emitters using Monte Carlo simulation of ICRP male thorax voxel phantom.

    PubMed

    Nadar, M Y; Akar, D K; Rao, D D; Kulkarni, M S; Pradeepkumar, K S

    2015-12-01

    Assessment of intake due to long-lived actinides by inhalation pathway is carried out by lung monitoring of the radiation workers inside totally shielded steel room using sensitive detection systems such as Phoswich and an array of HPGe detectors. In this paper, uncertainties in the lung activity estimation due to positional errors, chest wall thickness (CWT) and detector background variation are evaluated. First, calibration factors (CFs) of Phoswich and an array of three HPGe detectors are estimated by incorporating ICRP male thorax voxel phantom and detectors in Monte Carlo code 'FLUKA'. CFs are estimated for the uniform source distribution in lungs of the phantom for various photon energies. The variation in the CFs for positional errors of ±0.5, 1 and 1.5 cm in horizontal and vertical direction along the chest are studied. The positional errors are also evaluated by resizing the voxel phantom. Combined uncertainties are estimated at different energies using the uncertainties due to CWT, detector positioning, detector background variation of an uncontaminated adult person and counting statistics in the form of scattering factors (SFs). SFs are found to decrease with increase in energy. With HPGe array, highest SF of 1.84 is found at 18 keV. It reduces to 1.36 at 238 keV.

  1. Evidence Review Group approaches to the critical appraisal of manufacturer submissions for the NICE STA process: a mapping study and thematic analysis.

    PubMed

    Kaltenthaler, E; Boland, A; Carroll, C; Dickson, R; Fitzgerald, P; Papaioannou, D

    2011-05-01

    The National Institute for Health and Clinical Excellence (NICE) single technology appraisal (STA) process was set up as a rapid way to appraise new technologies for use within the NHS in England and Wales and has been in place since 2005. This study had five primary objectives: (1) to provide a map of the STA process to date; (2) to identify current approaches to the critical appraisal of manufacturers' submissions (MSs) by Evidence Review Groups (ERGs); (3) to identify recurring themes in clarification letters sent to manufacturers; (4) to provide recommendations for possible alternative approaches to be used in the critical appraisal process; and (5) to revise the current ERG report template. Data for the mapping of the STA process were obtained from the NICE website (www.nice.org.uk). Data for the analyses of the ERG reports and clarification letters were taken from the reports and letters themselves. For the mapping, a spreadsheet was developed to collect data on 22 predefined variables related to timings and outcomes. Simple descriptive statistics were used to analyse the data. For the thematic analysis, a documentary analysis of 30 ERG reports was undertaken. Data on key elements of the MSs, the processes undertaken by ERGs and the strengths and weaknesses of MSs were extracted. A framework of a priori themes was developed. Data were extracted, coded and analysed according to a framework approach. Twenty-one clarification letters were examined and data were extracted using a set of codes to cover report quality, systematic review methods and clinical/economic issues. The current ERG report template was modified and sent to the current ERG teams for comment. All comments were considered and formed the basis for further revisions to the template. Ninety-five STAs were included in the mapping exercise. Many STAs were subject to delay or cancellation for a variety of reasons. The ERG reports highlighted the strengths and weaknesses of MSs to the STA process

  2. A survey of doses to worker groups in the nuclear industry

    SciTech Connect

    Khan, T.A.; Baum, J.W.

    1991-01-01

    The the US National Council on Radiation Protection and Measurements (NCRP) has suggested ...as guidance for radiation programs that cumulative exposure not exceed the age of the individual in years {times} 10 mSv (years {times} 1 rem).'' The International Commission on Radiological Protection (ICRP) has recommended a dose limit of 10 rem averaged over 5 years. With these developments in mind, the US Nuclear Regulatory Commission (NRC) requested the ALARA Center of the Brookhaven National Laboratory to undertake two parallel studies. One study, which is still ongoing, is to examine the impact of the newly recommended dose limits on the nuclear industry as a whole; the other study was intended to assist in this larger project by looking more closely at the nuclear power industry. Preliminary data had indicated that the critical industry as far as the impact of new regulatory limits were concerned would be the nuclear power industry, because, it was conjectured, there existed a core of highly skilled workers in some groups which routinely get higher than average exposures. The objectives of the second study were to get a better understanding of the situation vis {grave a} vis the nuclear power industry, by identifying the high-dose worker groups, quantifying the annual and lifetime doses to these groups to see the extent of the problem if there was one, and finally to determine if there were any dose-reduction techniques which were particularly suited to reducing doses to these groups. In this presentation we describe some of the things learned during our work on the two projects. For more detailed information on the project on dose-reduction techniques for high-dose worker groups in the nuclear power industry, see NUREG/CR-5139. An industry/advisory committee has been set up which is in the process of evaluating the data from the larger project on the impact of new dose limits and will shortly produce its report. 7 refs., 5 figs., 6 tabs.

  3. In-Between Critical Mathematics Education and Ethnomathematics. A Philosophical Reflection and an Empirical Case of a Romany Students' Group Mathematics Education

    ERIC Educational Resources Information Center

    Francois, Karen; Stathopoulou, Charoula

    2012-01-01

    Although D' Ambrosio (2001) in his later work speaks about the political dimension of Ethnomathematics as "an evidence" and the researchers of Critical Mathematics Education have incorporated ethnomathematical ideas in their research, these two approaches are up to now perceived as separate research fields. In this paper we briefly…

  4. "I Owe It to My Group Members…who Critically Commented on My Conducting"--Cooperative Learning in Choral Conducting Education

    ERIC Educational Resources Information Center

    Varvarigou, Maria

    2016-01-01

    This article explores cooperative learning in choral conducting education. The five characteristics of cooperative learning identified by Adams and Hamm ((1996). "Cooperative learning: Critical thinking and collaboration across the curriculum" (2nd ed.). Springfield, IL: Charles Thomas Publishers): positive interdependence; face-to-face…

  5. "I Owe It to My Group Members…who Critically Commented on My Conducting"--Cooperative Learning in Choral Conducting Education

    ERIC Educational Resources Information Center

    Varvarigou, Maria

    2016-01-01

    This article explores cooperative learning in choral conducting education. The five characteristics of cooperative learning identified by Adams and Hamm ((1996). "Cooperative learning: Critical thinking and collaboration across the curriculum" (2nd ed.). Springfield, IL: Charles Thomas Publishers): positive interdependence; face-to-face…

  6. SimDoseCT: dose reporting software based on Monte Carlo simulation for a 320 detector-row cone-beam CT scanner and ICRP computational adult phantoms

    NASA Astrophysics Data System (ADS)

    Cros, Maria; Joemai, Raoul M. S.; Geleijns, Jacob; Molina, Diego; Salvadó, Marçal

    2017-08-01

    This study aims to develop and test software for assessing and reporting doses for standard patients undergoing computed tomography (CT) examinations in a 320 detector-row cone-beam scanner. The software, called SimDoseCT, is based on the Monte Carlo (MC) simulation code, which was developed to calculate organ doses and effective doses in ICRP anthropomorphic adult reference computational phantoms for acquisitions with the Aquilion ONE CT scanner (Toshiba). MC simulation was validated by comparing CTDI measurements within standard CT dose phantoms with results from simulation under the same conditions. SimDoseCT consists of a graphical user interface connected to a MySQL database, which contains the look-up-tables that were generated with MC simulations for volumetric acquisitions at different scan positions along the phantom using any tube voltage, bow tie filter, focal spot and nine different beam widths. Two different methods were developed to estimate organ doses and effective doses from acquisitions using other available beam widths in the scanner. A correction factor was used to estimate doses in helical acquisitions. Hence, the user can select any available protocol in the Aquilion ONE scanner for a standard adult male or female and obtain the dose results through the software interface. Agreement within 9% between CTDI measurements and simulations allowed the validation of the MC program. Additionally, the algorithm for dose reporting in SimDoseCT was validated by comparing dose results from this tool with those obtained from MC simulations for three volumetric acquisitions (head, thorax and abdomen). The comparison was repeated using eight different collimations and also for another collimation in a helical abdomen examination. The results showed differences of 0.1 mSv or less for absolute dose in most organs and also in the effective dose calculation. The software provides a suitable tool for dose assessment in standard adult patients undergoing CT

  7. WE-E-BRE-01: An Image-Based Skeletal Dosimetry Model for the ICRP Reference Adult Female - Internal Electron Sources

    SciTech Connect

    O'Reilly, S; Maynard, M; Marshall, E; Bolch, W; Sinclair, L; Rajon, D; Wayson, M

    2014-06-15

    Purpose: Limitations seen in previous skeletal dosimetry models, which are still employed in commonly used software today, include the lack of consideration of electron escape and cross-fire from cortical bone, the modeling of infinite spongiosa, the disregard of the effect of varying cellularity on active marrow self-irradiation, and the lack of use of the more recent ICRP definition of a 50 micron surrogate tissue region for the osteoprogenitor cells - shallow marrow. These limitations were addressed in the present dosimetry model. Methods: Electron transport was completed to determine specific absorbed fractions to active marrow and shallow marrow of the skeletal regions of the adult female. The bone macrostructure was obtained from the whole-body hybrid computational phantom of the UF series of reference phantoms, while the bone microstructure was derived from microCT images of skeletal region samples taken from a 45 year-old female cadaver. The target tissue regions were active marrow and shallow marrow. The source tissues were active marrow, inactive marrow, trabecular bone volume, trabecular bone surfaces, cortical bone volume and cortical bone surfaces. The marrow cellularity was varied from 10 to 100 percent for active marrow self-irradiation. A total of 33 discrete electron energies, ranging from 1 keV to 10 MeV, were either simulated or modeled analytically. Results: The method of combining macro- and microstructure absorbed fractions calculated using MCNPX electron transport was found to yield results similar to those determined with the PIRT model for the UF adult male in the Hough et al. study. Conclusion: The calculated skeletal averaged absorbed fractions for each source-target combination were found to follow similar trends of more recent dosimetry models (image-based models) and did not follow current models used in nuclear medicine dosimetry at high energies (due to that models use of an infinite expanse of trabecular spongiosa)

  8. SimDoseCT: dose reporting software based on Monte Carlo simulation for a 320 detector-row cone-beam CT scanner and ICRP computational adult phantoms.

    PubMed

    Cros, Maria; Joemai, Raoul M S; Geleijns, Jacob; Molina, Diego; Salvadó, Marçal

    2017-07-17

    This study aims to develop and test software for assessing and reporting doses for standard patients undergoing computed tomography (CT) examinations in a 320 detector-row cone-beam scanner. The software, called SimDoseCT, is based on the Monte Carlo (MC) simulation code, which was developed to calculate organ doses and effective doses in ICRP anthropomorphic adult reference computational phantoms for acquisitions with the Aquilion ONE CT scanner (Toshiba). MC simulation was validated by comparing CTDI measurements within standard CT dose phantoms with results from simulation under the same conditions. SimDoseCT consists of a graphical user interface connected to a MySQL database, which contains the look-up-tables that were generated with MC simulations for volumetric acquisitions at different scan positions along the phantom using any tube voltage, bow tie filter, focal spot and nine different beam widths. Two different methods were developed to estimate organ doses and effective doses from acquisitions using other available beam widths in the scanner. A correction factor was used to estimate doses in helical acquisitions. Hence, the user can select any available protocol in the Aquilion ONE scanner for a standard adult male or female and obtain the dose results through the software interface. Agreement within 9% between CTDI measurements and simulations allowed the validation of the MC program. Additionally, the algorithm for dose reporting in SimDoseCT was validated by comparing dose results from this tool with those obtained from MC simulations for three volumetric acquisitions (head, thorax and abdomen). The comparison was repeated using eight different collimations and also for another collimation in a helical abdomen examination. The results showed differences of 0.1 mSv or less for absolute dose in most organs and also in the effective dose calculation. The software provides a suitable tool for dose assessment in standard adult patients undergoing CT

  9. Validation of the ICRP model for caesium intake by lactating mothers with Italian data after the Chernobyl fallout.

    PubMed

    Giussani, Augusto; Risica, Serena

    2012-02-01

    In the aftermath of the Chernobyl nuclear power plant accident, a research group of the Italian National Institute of Health (Istituto Superiore di Sanità) carried out two research programmes on maternal milk. One concerned the transfer of caesium radionuclides from the diet to breast milk. In the other, the activity concentrations of (137)Cs were also determined in urine and placenta. The first study estimated the mothers' average (137)Cs dietary intake, in the second study the intake was evaluated individually for each subject. In 2004, the International Commission on Radiological Protection published modified systemic biokinetic models which also account for transfer to breast milk. The model for caesium radionuclides was implemented and tested by the authors with the experimental data described above. A good agreement was obtained between measured data and model simulations of (137)Cs activity concentration in human milk. The model, however, tends to systematically overestimate (137)Cs activity concentration in urine, in which case the agreement is to be considered satisfactory in terms of order of magnitude.

  10. A critical analysis of prognostic factors for survival in intermediate and high grade non-Hodgkin's lymphoma. Scotland and Newcastle Lymphoma Group Therapy Working Party.

    PubMed Central

    Hayward, R. L.; Leonard, R. C.; Prescott, R. J.

    1991-01-01

    Between 1979 and 1987 the Scotland and Newcastle Lymphoma Group registered 972 adults with Working Formulation high or intermediate grade non-Hodgkin's lymphoma. Clinical, pathological and investigational data were recorded prospectively on a computer database allowing analysis for prognostic factors. We have derived prognostically important characteristics and have tested prospectively the validity of the prognostic index on a geographically distinct sub-set of patients from the Edinburgh/Borders clinics. Multivariate analysis showed the following factors to be important in declining order of power; advancing age, worsening performance status, CNS/liver involvement, abnormal white cell count, 'B' symptoms and advancing clinical stage. Patient individual scores allowed them to be aggregated into one of three distinct prognostic groupings separated by arbitrary cut-points into a Best Group (39%) where the median survival exceeds 5 years (53% alive at 5 years), an Intermediate Group (30%) with median survival of 21 months (21% alive at 5 years), and a Worst Group (31%) whose median survival is 7 months (8% alive at 5 years). Similar prognostic group separations occurred when analysis was confined to: patients younger than 70 years; patients treated with initial chemotherapy; patients treated with initial radiotherapy; patients within any of the major pathological sub-groups. PMID:2069849

  11. Quantitative analysis of oleic acid and three types of polyethers according to the number of hydroxy end groups in Polysorbate 80 by hydrophilic interaction chromatography at critical conditions.

    PubMed

    Zhang, Rui; Wang, Yu; Ji, Yu; Shi, Bei-jia; Zhang, Zai-ping; Zhang, Hai-yan; Yang, Ming; Wang, Yong-mei

    2013-01-11

    A quantitative characterization of Polysorbate 80 is crucial for its many applications. In this paper we report a quick RP-HPLC method for the quantitative determination of Polysorbate 80. The hydrolysis of Polysorbate 80 to release oleic acid and three types of polyethers was first carried out. A chromatographic method based on liquid chromatography at critical conditions (LCCC) was then developed for an endgroup-based separation of low-molecular-mass polyether. With this method the polyether, irrespective of its molecular-mass, is separated according to endgroups (functionality) due to interactions of the polar endgroups with the hydrophilic stationary phase. The different types of polyethers and oleic acid were identified using on-line electrospray ionization mass spectrometry and quantified by evaporative light scattering detection.

  12. Implications of the Holmes Group and the Carnegie Commission Reports for Vocational Teacher Education. Symposium on Critical Issues in Vocational Teacher Education and Strategies for Improvement.

    ERIC Educational Resources Information Center

    Smith, Charles W.; And Others

    This document contains four papers presented at a panel on implications of the Holmes Group and the Carnegie Commission reports for vocational teacher education. In the first paper, Charles W. Smith discusses general issues concerning the emergence of the education reform movement and calls for vocational educators to be part of the reform…

  13. Critical rearing parameters of Tetrastichus planipennisi (Hymenoptera: Eulophidae) as affected by host-plant substrate and host-parasitoid group structure

    USDA-ARS?s Scientific Manuscript database

    Laboratory studies were conducted to evaluate the potential impact of host-plant substrate types, host-parasitoid group size and host to parasitoid ratios on select fitness parameters of the larval parasitoid Tetrastichus planipennisi Yang, newly introduced for biological control of the invasive eme...

  14. Implications of the Holmes Group and the Carnegie Commission Reports for Vocational Teacher Education. Symposium on Critical Issues in Vocational Teacher Education and Strategies for Improvement.

    ERIC Educational Resources Information Center

    Smith, Charles W.; And Others

    This document contains four papers presented at a panel on implications of the Holmes Group and the Carnegie Commission reports for vocational teacher education. In the first paper, Charles W. Smith discusses general issues concerning the emergence of the education reform movement and calls for vocational educators to be part of the reform…

  15. Are senior nurses on Clinical Commissioning Groups in England inadvertently supporting the devaluation of their profession?: A critical integrative review of the literature.

    PubMed

    Allan, Helen Therese; Dixon, Roz; Lee, Gay; O'Driscoll, Michael; Savage, Jan; Tapson, Christine

    2016-06-01

    In this study, we discuss the role of senior nurses who sit on clinical commissioning groups that now plan and procure most health services in England. These nurses are expected to bring a nursing view to all aspects of clinical commissioning group business. The role is a senior level appointment and requires experience of strategic commissioning. However, little is known about how nurses function in these roles. Following Barrientos' methodology, published policy and literature were analysed to investigate these roles and National Health Service England's claim that nursing can influence and advance a nursing perspective in clinical commissioning groups. Drawing on work by Berg, Barry and Chandler on 'new public management', we discuss how nurses on clinical commissioning groups work at the alignment of the interests of biomedicine and managerialism. We propose that the way this nursing role is being implemented might paradoxically offer further evidence of the devaluing of nursing rather than the emergence of a strong professional nursing voice at the level of strategic commissioning. © 2016 John Wiley & Sons Ltd.

  16. A shift in task routines during the learning of a motor skill: group-averaged data may mask critical phases in the individuals' acquisition of skilled performance.

    PubMed

    Adi-Japha, Esther; Karni, Avi; Parnes, Ariel; Loewenschuss, Iris; Vakil, Eli

    2008-11-01

    The authors describe a transient phase during training on a movement sequence wherein, after an initial improvement in speed and decrease in variability, individual participants' performance showed a significant increase in variability without change in mean performance speed. Subsequent to this phase, as practice continued, variability again decreased, performance significantly exceeded the gains predicted by extrapolation of the initial learning curve, the type of errors committed changed, and performance became more coherent. The transient phase of increased variability may reflect a mixture of 2 (or more) performance routines before the more effective one is set and mastered, presumably the setting up of a sequence-specific representation. Both group and individual analyses indicated a departure from the single process (e.g., power-law) model of learning. However, although similar phases appeared in the mean group data, there was little correspondence to individual participants' time courses, and the individuals' gains in the second low-variability phase were masked.

  17. Critical appraisal of arguments for the delayed-start design proposed as alternative to the parallel-group randomized clinical trial design in the field of rare disease.

    PubMed

    Spineli, Loukia M; Jenz, Eva; Großhennig, Anika; Koch, Armin

    2017-08-17

    A number of papers have proposed or evaluated the delayed-start design as an alternative to the standard two-arm parallel group randomized clinical trial (RCT) design in the field of rare disease. However the discussion is felt to lack a sufficient degree of consideration devoted to the true virtues of the delayed start design and the implications either in terms of required sample-size, overall information, or interpretation of the estimate in the context of small populations. To evaluate whether there are real advantages of the delayed-start design particularly in terms of overall efficacy and sample size requirements as a proposed alternative to the standard parallel group RCT in the field of rare disease. We used a real-life example to compare the delayed-start design with the standard RCT in terms of sample size requirements. Then, based on three scenarios regarding the development of the treatment effect over time, the advantages, limitations and potential costs of the delayed-start design are discussed. We clarify that delayed-start design is not suitable for drugs that establish an immediate treatment effect, but for drugs with effects developing over time, instead. In addition, the sample size will always increase as an implication for a reduced time on placebo resulting in a decreased treatment effect. A number of papers have repeated well-known arguments to justify the delayed-start design as appropriate alternative to the standard parallel group RCT in the field of rare disease and do not discuss the specific needs of research methodology in this field. The main point is that a limited time on placebo will result in an underestimated treatment effect and, in consequence, in larger sample size requirements compared to those expected under a standard parallel-group design. This also impacts on benefit-risk assessment.

  18. Absorbed dose estimations of 131I for critical organs using the GEANT4 Monte Carlo simulation code

    NASA Astrophysics Data System (ADS)

    Ziaur, Rahman; Shakeel, ur Rehman; Waheed, Arshed; Nasir, M. Mirza; Abdul, Rashid; Jahan, Zeb

    2012-11-01

    The aim of this study is to compare the absorbed doses of critical organs of 131I using the MIRD (Medical Internal Radiation Dose) with the corresponding predictions made by GEANT4 simulations. S-values (mean absorbed dose rate per unit activity) and energy deposition per decay for critical organs of 131I for various ages, using standard cylindrical phantom comprising water and ICRP soft-tissue material, have also been estimated. In this study the effect of volume reduction of thyroid, during radiation therapy, on the calculation of absorbed dose is also being estimated using GEANT4. Photon specific energy deposition in the other organs of the neck, due to 131I decay in the thyroid organ, has also been estimated. The maximum relative difference of MIRD with the GEANT4 simulated results is 5.64% for an adult's critical organs of 131I. Excellent agreement was found between the results of water and ICRP soft tissue using the cylindrical model. S-values are tabulated for critical organs of 131I, using 1, 5, 10, 15 and 18 years (adults) individuals. S-values for a cylindrical thyroid of different sizes, having 3.07% relative differences of GEANT4 with Siegel & Stabin results. Comparison of the experimentally measured values at 0.5 and 1 m away from neck of the ionization chamber with GEANT4 based Monte Carlo simulations results show good agreement. This study shows that GEANT4 code is an important tool for the internal dosimetry calculations.

  19. A Monte Carlo based nodal diffusion model for criticality analysis, and, Application of high-order cross section homogenization method to two-group nodal diffusion

    NASA Astrophysics Data System (ADS)

    Ilas, Germina

    In the first part, an accurate and fast computational method is presented as an alternative to the Monte Carlo or deterministic transport theory codes currently used to determine the subcriticality of spent fuel storage lattices. The method is capable of analyzing storage configurations with simple or complex lattice cell geometry. It is developed based on two-group nodal diffusion theory, with the nodal cross sections and discontinuity factors determined from continuous-energy Monte Carlo simulations of each unique node (spent fuel assembly type). Three different approaches are developed to estimate the node-averaged diffusion coefficient. The applicability and the accuracy of the nodal method are assessed in two-dimensional geometry through several benchmark configurations typical at Savannah River Site. It is shown that the multiplication constant of the analyzed configurations is within 1% of the MCNP results. In the second part, the high-order cross section homogenization method, recently developed by McKinley and Rahnema, is implemented in the context of two-group nodal diffusion theory. The method corrects the generalized equivalence theory homogenization parameters for the effect of the core environment. The reconstructed fine-mesh (fuel pin) flux and power distributions are a natural byproduct of this method. The method was not tested for multigroup problems, where it was assumed that the multigroup flux expansion in terms of the perturbation parameter is a convergent series. Here the applicability of the method to two-group problems is studied, and it is shown that the perturbation expansion series converges for the multigroup case. A two-group nodal diffusion code with a bilinear intra-nodal flux shape is developed for the implementation of the high-order homogenization method in the context of the generalized equivalence theory. The method is tested by using as a benchmark a core configuration typical of a BWR in slab geometry, which has large

  20. Structure-Activity Relationships of the Competence Stimulating Peptides (CSPs) in Streptococcus pneumoniae Reveal Motifs Critical for Intra-group and Cross-group ComD Receptor Activation.

    PubMed

    Yang, Yifang; Koirala, Bimal; Sanchez, Lucia A; Phillips, Naiya R; Hamry, Sally R; Tal-Gan, Yftah

    2017-03-10

    Streptococcus pneumoniae is a highly recombinogenic human pathogen that utilizes the competence stimulating peptide (CSP)-based quorum sensing (QS) circuitry to acquire antibiotic resistance genes from the environment and initiate its attack on the human host. Modulation of QS in this bacterium, either inhibition or activation, can therefore be used to attenuate S. pneumoniae infectivity and slow down pneumococcal resistance development. In this study, we set to determine the molecular mechanism that drives CSP:receptor binding and identify CSP-based QS modulators with distinct activity profiles. To this end, we conducted systematic replacement of the amino acid residues in the two major CSP signals (CSP1 and CSP2) and assessed the ability of the mutated analogs to modulate QS against both cognate and noncognate ComD receptors. We then evaluated the overall 3D structures of these analogs using circular dichroism (CD) to correlate between the structure and function of these peptides. Our CD analysis revealed a strong correlation between α-helicity and bioactivity for both specificity groups (CSP1 and CSP2). Furthermore, we identified the first pan-group QS activator and the most potent group-II QS inhibitor to date. These chemical probes can be used to study the role of QS in S. pneumoniae and as scaffolds for the design of QS-based anti-infective therapeutics against S. pneumoniae infections.

  1. Making Sense of Critical Pedagogy in L2 Education through a Collaborative Study Group (Dándole sentido a la pedagogía crítica en la educación en L2 a través de un grupo de estudio colaborativo)

    ERIC Educational Resources Information Center

    Echeverri Sucerquia, Paula Andrea; Pérez Restrepo, Sebastián

    2014-01-01

    In this article we discuss our experiences in the process of understanding critical pedagogy within an English teachers' study group which was created for the purpose of learning how to teach language from a critical perspective. We particularly focus on the challenges of meaning making around critical pedagogy, as we realized that we were not all…

  2. Toll-like receptor 4 and high-mobility group box 1 are critical mediators of tissue injury and survival in a mouse model for heatstroke.

    PubMed

    Dehbi, Mohammed; Uzzaman, Taher; Baturcam, Engin; Eldali, Abdelmoneim; Ventura, Wilhelmina; Bouchama, Abderrezak

    2012-01-01

    The molecular mechanisms that initiate the inflammatory response in heatstroke and their relation with tissue injury and lethality are not fully elucidated. We examined whether endogenous ligands released by damaged/stressed cells such as high-mobility group box 1 (HMGB1) signaling through Toll-like receptor 4 (TLR4) may play a pathogenic role in heatstroke. Mutant TLR4-defective (C3H/HeJ) and wild type (C3H/HeOuJ) mice were subjected to heat stress in an environmental chamber pre-warmed at 43.5 °C until their core temperature reached 42.7°C, which was taken as the onset of heatstroke. The animals were then allowed to recover passively at ambient temperature. A sham-heated group served as a control. Mutant mice displayed more histological liver damage and higher mortality compared with wild type mice (73% vs. 27%, respectively, P<0.001). Compared to wild type mice, mutant mice exhibited earlier plasma release of markers of systemic inflammation such as HMGB1 (206 ± 105 vs. 63 ± 21 ng/ml; P = 0.0018 and 209 ± 100 vs. 46 ± 32 ng/ml; P<0.0001), IL-6 (144 ± 40 vs. 46 ± 20 pg/ml; P<0.001 and 184 ± 21 vs. 84 ± 54 pg/ml; P = 0.04), and IL-1β (27 ± 4 vs. 1.7 ± 2.3 pg/ml; P<0.0001 at 1 hour). Both strains of mice displayed early release of HMGB1 into the circulation upstream of IL-1β and IL-6 responses which remained elevated up to 24 h. Specific inhibition of HMGB1 activity with DNA-binding A Box (600 µg/mouse) protected the mutant mice against the lethal effect of heat stress (60% A Box vs. 18% GST protein, P = 0.04). These findings suggest a protective role for the TLR4 in the host response to severe heat stress. They also suggest that HMGB1 is an early mediator of inflammation, tissue injury and lethality in heatstroke in the presence of defective TLR4 signaling.

  3. Disparities in health, poverty, incarceration, and social justice among racial groups in the United States: a critical review of evidence of close links with neoliberalism.

    PubMed

    Nkansah-Amankra, Stephen; Agbanu, Samuel Kwami; Miller, Reuben Jonathan

    2013-01-01

    Problems of poverty, poor health, and incarceration are unevenly distributed among racial and ethnic minorities in the United States. We argue that this is due, in part, to the ascendance of United States-style neoliberalism, a prevailing political and economic doctrine that shapes social policy, including public health and anti-poverty intervention strategies. Public health research most often associates inequalities in health outcomes, poverty, and incarceration with individual and cultural risk factors. Contextual links to structural inequality and the neoliberal doctrine animating state-sanctioned interventions are given less attention. The interrelationships among these are not clear in the extant literature. Less is known about public health and incarceration. Thus, the authors describe the linkages between neoliberalism, public health, and criminal justice outcomes. We suggest that neoliberalism exacerbates racial disparities in health, poverty, and incarceration in the United States. We conclude by calling for a new direction in public health research that advances a pro-poor public health agenda to improve the general well-being of disadvantaged groups.

  4. Critical role of phospholipase A2 group IID in age-related susceptibility to severe acute respiratory syndrome–CoV infection

    PubMed Central

    Vijay, Rahul; Hua, Xiaoyang; Meyerholz, David K.; Miki, Yoshimi; Yamamoto, Kei; Gelb, Michael; Murakami, Makoto

    2015-01-01

    Oxidative stress and chronic low-grade inflammation in the lungs are associated with aging and may contribute to age-related immune dysfunction. To maintain lung homeostasis, chronic inflammation is countered by enhanced expression of proresolving/antiinflammatory factors. Here, we show that age-dependent increases of one such factor in the lungs, a phospholipase A2 (PLA2) group IID (PLA2G2D) with antiinflammatory properties, contributed to worse outcomes in mice infected with severe acute respiratory syndrome-coronavirus (SARS-CoV). Strikingly, infection of mice lacking PLA2G2D expression (Pla2g2d−/− mice) converted a uniformly lethal infection to a nonlethal one (>80% survival), subsequent to development of enhanced respiratory DC migration to the draining lymph nodes, augmented antivirus T cell responses, and diminished lung damage. We also observed similar effects in influenza A virus–infected middle-aged Pla2g2d−/− mice. Furthermore, oxidative stress, probably via lipid peroxidation, was found to induce PLA2G2D expression in mice and in human monocyte–derived macrophages. Thus, our results suggest that directed inhibition of a single inducible phospholipase, PLA2G2D, in the lungs of older patients with severe respiratory infections is potentially an attractive therapeutic intervention to restore immune function. PMID:26392224

  5. Nuclear decay data files of the Dosimetry Research Group

    SciTech Connect

    Eckerman, K.F.; Westfall, R.J.; Ryman, J.C.; Cristy, M.

    1993-12-01

    This report documents the nuclear decay data files used by the Dosimetry Research Group at Oak Ridge National Laboratory and the utility DEXRAX which provides access to the files. The files are accessed, by nuclide, to extract information on the intensities and energies of the radiations associated with spontaneous nuclear transformation of the radionuclides. In addition, beta spectral data are available for all beta-emitting nuclides. Two collections of nuclear decay data are discussed. The larger collection contains data for 838 radionuclides, which includes the 825 radionuclides assembled during the preparation of Publications 30 and 38 of the International Commission on Radiological Protection (ICRP) and 13 additional nuclides evaluated in preparing a monograph for the Medical Internal Radiation Dose (MIRD) Committee of the Society of Nuclear Medicine. The second collection is composed of data from the MIRD monograph and contains information for 242 radionuclides. Abridged tabulations of these data have been published by the ICRP in Publication 38 and by the Society of Nuclear Medicine in a monograph entitled ``MIRD: Radionuclide Data and Decay Schemes.`` The beta spectral data reported here have not been published by either organization. Electronic copies of the files and the utility, along with this report, are available from the Radiation Shielding Information Center at Oak Ridge National Laboratory.

  6. Thinking Critically about Critical Thinking

    ERIC Educational Resources Information Center

    Mulnix, Jennifer Wilson

    2012-01-01

    As a philosophy professor, one of my central goals is to teach students to think critically. However, one difficulty with determining whether critical thinking can be taught, or even measured, is that there is widespread disagreement over what critical thinking actually is. Here, I reflect on several conceptions of critical thinking, subjecting…

  7. Thinking Critically about Critical Thinking

    ERIC Educational Resources Information Center

    Mulnix, Jennifer Wilson

    2012-01-01

    As a philosophy professor, one of my central goals is to teach students to think critically. However, one difficulty with determining whether critical thinking can be taught, or even measured, is that there is widespread disagreement over what critical thinking actually is. Here, I reflect on several conceptions of critical thinking, subjecting…

  8. How critical is chronic critical leg ischaemia?

    PubMed

    Kroese, A J; Stranden, E

    1998-01-01

    "Critical" according to the Oxford dictionary means: a "turning point" where an acute change for better or worse may be anticipated. Thus, the meaning of the word "critical" complies with its use in relation to ischaemia. We don't really know, prospectively, what will happen to the critically ischaemic limb, whether it will improve or worsen. The answer to the question "How critical is critical leg ischaemia (CLI)?" must be: "We don't know!" The addition of ankle systolic pressure as an objective haemodynamic measurement has not made the definition of the Second European Consensus Group significantly better than the original Fontaine classification, grade III and IV. For clinical practice the Fontaine classification will be sufficient. For scientific purposes macro- and microcirculatory assessments and information about the patient's risk profile should be added.

  9. RPI-AM and RPI-AF, a pair of mesh-based, size-adjustable adult male and female computational phantoms using ICRP-89 parameters and their calculations for organ doses from monoenergetic photon beams

    PubMed Central

    Zhang, Juying; Na, Yong Hum; Caracappa, Peter F; Xu, X George

    2010-01-01

    This paper describes the development of a pair of adult male and adult female computational phantoms that are compatible with anatomical parameters for the 50th percentile population as specified by the International Commission on Radiological Protection (ICRP). The phantoms were designed entirely using polygonal mesh surfaces—a Boundary REPresentation (BREP) geometry that affords the ability to efficiently deform the shape and size of individual organs, as well as the body posture. A set of surface mesh models, from Anatomium™ 3D P1 V2.0, including 140 organs (out of 500 available) was adopted to supply the basic anatomical representation at the organ level. The organ masses were carefully adjusted to agree within 0.5% relative error with the reference values provided in the ICRP Publication 89. The finalized phantoms have been designated the RPI adult male (RPI-AM) and adult female (RPI-AF) phantoms. For the purposes of organ dose calculations using the MCNPX Monte Carlo code, these phantoms were subsequently converted to voxel formats. Monoenergetic photons between 10 keV and 10 MeV in six standard external photon source geometries were considered in this study: four parallel beams (anterior–posterior, posterior–anterior, left lateral and right lateral), one rotational and one isotropic. The results are tabulated as fluence-to-organ-absorbed-dose conversion coefficients and fluence-to-effective-dose conversion coefficients and compared against those derived from the ICRP computational phantoms, REX and REGINA. A general agreement was found for the effective dose from these two sets of phantoms for photon energies greater than about 300 keV. However, for low-energy photons and certain individual organs, the absorbed doses exhibit profound differences due to specific anatomical features. For example, the position of the arms affects the dose to the lung by more than 20% below 300 keV in the lateral source directions, and the vertical position of the testes

  10. Critical Care

    MedlinePlus

    Critical care helps people with life-threatening injuries and illnesses. It might treat problems such as complications from surgery, ... attention by a team of specially-trained health care providers. Critical care usually takes place in an ...

  11. Archetypal Criticism.

    ERIC Educational Resources Information Center

    Chesebro, James W.; And Others

    1990-01-01

    Argues that archetypal criticism is a useful way of examining universal, historical, and cross-cultural symbols in classrooms. Identifies essential features of an archetype; outlines operational and critical procedures; illustrates archetypal criticism as applied to the cross as a symbol; and provides a synoptic placement for archetypal criticism…

  12. How Critical Is Critical Thinking?

    ERIC Educational Resources Information Center

    Shaw, Ryan D.

    2014-01-01

    Recent educational discourse is full of references to the value of critical thinking as a 21st-century skill. In music education, critical thinking has been discussed in relation to problem solving and music listening, and some researchers suggest that training in critical thinking can improve students' responses to music. But what exactly is…

  13. Critical Thinking vs. Critical Consciousness

    ERIC Educational Resources Information Center

    Doughty, Howard A.

    2006-01-01

    This article explores four kinds of critical thinking. The first is found in Socratic dialogues, which employ critical thinking mainly to reveal logical fallacies in common opinions, thus cleansing superior minds of error and leaving philosophers free to contemplate universal verities. The second is critical interpretation (hermeneutics) which…

  14. Critically Thinking about Critical Thinking

    ERIC Educational Resources Information Center

    Weissberg, Robert

    2013-01-01

    In this article, the author states that "critical thinking" has mesmerized academics across the political spectrum and that even high school students are now being called upon to "think critically." He furthers adds that it is no exaggeration to say that "critical thinking" has quickly evolved into a scholarly…

  15. How Critical Is Critical Thinking?

    ERIC Educational Resources Information Center

    Shaw, Ryan D.

    2014-01-01

    Recent educational discourse is full of references to the value of critical thinking as a 21st-century skill. In music education, critical thinking has been discussed in relation to problem solving and music listening, and some researchers suggest that training in critical thinking can improve students' responses to music. But what exactly is…

  16. A critical quantum chemical and experimental study of the potentiality of direct labeling of the CN group with [(99m)Tc(CO)(3)](+) or [(186/188)Re(CO)(3)](+) in CN containing biomolecules.

    PubMed

    Safi, Benasser; Mertens, John; Kersemans, Ken; Geerlings, Paul

    2008-10-01

    It was determined recently that [(99m)Tc(OH(2))(2)(X(-))(CO(3))(3)] could strongly bind to the CN group, allowing direct labeling of CN in vitamin B(12) despite the presence of a benzimidazole group. The aim of this paper was to perform a critical study of this potentiality, coupling quantum chemical calculations to experimental evidence. Computational methods: Within the density functional theory calculations, the 6-31+G basis set (C, H, O, N atoms) and the LANL2DZ basis set (Tc,Re) were used. Stability calculations of the [RCNM(CO)(3)](+)) (M=Tc,Re) complexes were performed with the Gaussian 03 suite of programs, while for the evaluation of relative stability substitution reactions were used. Radiochemistry: Vitamin B(12), 4-hydroxy-benzylcyanide and 4-methoxy-benzonitrile were labeled at 100 degrees C during 30 min. High-performance liquid chromatography analysis was performed using radioactive and UV detection. Computational methods: The influence of different ligands on the stability yielded a sequence: imidazole>tBuCN>NH(3) approximately CH(3)CN>HCN (mimicking the best CoCN)>H(2)O. The transmetalation reaction indicates that all ligands prefer Re to Tc. The preference for the nitrogen atom of imidazole to the cyanide nitrogen atom for complex formation with [Tc(CO)(3)(H(2)O)(3)](+) is interpreted in terms of the hard and soft acid and base properties principle. Radiochemistry: 4-Hydroxy-benzylcyanide and 4-methoxy-benzonitrile did not show any labeling. An excess of acetonitrile did not inhibit the labeling of vitamin B(12) as expected if the CN group should be involved, indicating that the labeling occurs on a stronger complexing group present like benzimidazole. Both theory and experiments prove that [CN-Tc(CO)(3)(H(2)O)((2-x))L(x)](+) complexes are weak and that in vitamin B(12) most probably the benzimidazole group is involved.

  17. Criticality Model

    SciTech Connect

    A. Alsaed

    2004-09-14

    The ''Disposal Criticality Analysis Methodology Topical Report'' (YMP 2003) presents the methodology for evaluating potential criticality situations in the monitored geologic repository. As stated in the referenced Topical Report, the detailed methodology for performing the disposal criticality analyses will be documented in model reports. Many of the models developed in support of the Topical Report differ from the definition of models as given in the Office of Civilian Radioactive Waste Management procedure AP-SIII.10Q, ''Models'', in that they are procedural, rather than mathematical. These model reports document the detailed methodology necessary to implement the approach presented in the Disposal Criticality Analysis Methodology Topical Report and provide calculations utilizing the methodology. Thus, the governing procedure for this type of report is AP-3.12Q, ''Design Calculations and Analyses''. The ''Criticality Model'' is of this latter type, providing a process evaluating the criticality potential of in-package and external configurations. The purpose of this analysis is to layout the process for calculating the criticality potential for various in-package and external configurations and to calculate lower-bound tolerance limit (LBTL) values and determine range of applicability (ROA) parameters. The LBTL calculations and the ROA determinations are performed using selected benchmark experiments that are applicable to various waste forms and various in-package and external configurations. The waste forms considered in this calculation are pressurized water reactor (PWR), boiling water reactor (BWR), Fast Flux Test Facility (FFTF), Training Research Isotope General Atomic (TRIGA), Enrico Fermi, Shippingport pressurized water reactor, Shippingport light water breeder reactor (LWBR), N-Reactor, Melt and Dilute, and Fort Saint Vrain Reactor spent nuclear fuel (SNF). The scope of this analysis is to document the criticality computational method. The criticality

  18. Critical thinking.

    PubMed

    Price, A; Price, B

    1996-05-01

    Critical thinking is a process applied to midwifery theory, research and experience. It is a positive activity, responsive to context, drawing on negative and positive triggers and emotions to suggest ways of acting in future. Practice-based and reflective midwifery assignments should reflect the midwifery goals of critical thinking. This may require adjustments in assessment criteria and a questioning of standard academic conventions.

  19. Critical Muralism

    ERIC Educational Resources Information Center

    Rosette, Arturo

    2009-01-01

    This study focuses on the development and practices of Critical Muralists--community-educator-artist-leader-activists--and situates these specifically in relation to the Mexican mural tradition of los Tres Grandes and in relation to the history of public art more generally. The study examines how Critical Muralists address artistic and…

  20. Critics and Criticism of Education

    ERIC Educational Resources Information Center

    Ornstein, Allan C.

    1977-01-01

    Radical educational critics, such as Edgar Friedenberg, Paul Goodman, A. S. Neill, John Holt, Jonathan Kozol, Herbert Kohl, James Herndon, and Ivan Illich, have few constructive goals, no strategy for broad change, and a disdain for modernization and compromise. Additionally, these critics, says the author, fail to consider social factors related…

  1. The iodide-transport-defect-causing mutation R124H: a δ-amino group at position 124 is critical for maturation and trafficking of the Na+/I- symporter.

    PubMed

    Paroder, Viktoriya; Nicola, Juan P; Ginter, Christopher S; Carrasco, Nancy

    2013-08-01

    Na(+)/I(-) symporter (NIS)-mediated active accumulation of I(-) in thyrocytes is a key step in the biosynthesis of the iodine-containing thyroid hormones T3 and T4. Several NIS mutants have been identified as a cause of congenital I(-) transport defect (ITD), and their investigation has yielded valuable mechanistic information on NIS. Here we report novel findings derived from the thorough characterization of the ITD-causing mutation R124H, located in the second intracellular loop (IL-2). R124H NIS is incompletely glycosylated and colocalizes with endoplasmic reticulum (ER)-resident protein markers. As a result, R124H NIS is not targeted to the plasma membrane and therefore does not mediate any I(-) transport in transfected COS-7 cells. Strikingly, however, the mutant is intrinsically active, as revealed by its ability to mediate I(-) transport in membrane vesicles. Of all the amino acid substitutions we carried out at position 124 (K, D, E, A, W, N and Q), only Gln restored targeting of NIS to the plasma membrane and NIS activity, suggesting a key structural role for the δ-amino group of R124 in the transporter's maturation and cell surface targeting. Using our NIS homology model based on the structure of the Vibrio parahaemolyticus Na(+)/galactose symporter, we propose an interaction between the δ-amino group of either R or Q124 and the thiol group of C440, located in IL-6. We conclude that the interaction between IL-2 and IL-6 is critical for the local folding required for NIS maturation and plasma membrane trafficking.

  2. Taking criticism.

    PubMed

    Dowd, Steven B; Davidhizar, Ruth

    2006-01-01

    The manner in which criticism is dealt with is one of the important behaviors to master in a healthcare work environment: 1.) respond calmly, 2) use a problem solving approach, 3) avoid blaming others, 4) increase the complainers feelings of power, 4) increase feelings of power, 5) communicate respect, 6) do not respond to criticism with an e-mail, 7) forgive the complainer and not hold a grudge; and 8) let the buck stop as soon as possible, and 9) take criticism seriously. Dealing with criticism will never be easy. It just isn't! But using a reasoned approach will help, and get us back to why we entered healthcare - to take care of patients.

  3. Critical Careers.

    ERIC Educational Resources Information Center

    Bowles, Roger A.

    2001-01-01

    Reports the critical shortage of qualified equipment technicians, especially in biomedical equipment. Cites the importance of encouraging careers in this field and describes a source of occupational information. (SK)

  4. How Critical Is Critical Infrastructure?

    DTIC Science & Technology

    2015-09-01

    be misdirected even though it is the cornerstone mission of the department to prevent terrorism and enhance security. It is likely that the...facilities DHS works to protect from terrorism are not the most likely targets for attacks. The manner in which facilities are designated as critical...security, critical infrastructure, world trade center, military theory, terrorism 15. NUMBER OF PAGES 155 16. PRICE CODE 17. SECURITY CLASSIFICATION

  5. Heavy fermion quantum criticality.

    PubMed

    Nazario, Zaira; Santiago, David I

    2008-09-26

    During the last few years, investigations of rare-earth materials have made clear that heavy fermion quantum criticality exhibits novel physics not fully understood. In this work, we write for the first time the effective action describing the low energy physics of the system. The f fermions are replaced by a dynamical scalar field whose nonzero expected value corresponds to the heavy fermion phase. The effective theory is amenable to numerical studies as it is bosonic, circumventing the fermion sign problem. Via effective action techniques, renormalization group studies, and Callan-Symanzik resummations, we describe the heavy fermion criticality and predict the heavy fermion critical dynamical susceptibility and critical specific heat. The specific heat coefficient exponent we obtain (0.39) is in excellent agreement with the experimental result at low temperatures (0.4).

  6. Staying Critical

    ERIC Educational Resources Information Center

    Carr, Wilfred; Kemmis, Stephen

    2005-01-01

    In this article, the two authors of "Becoming Critical: education, knowledge and action research" look back at the book's history since its publication 20 years ago. We describe how the book was originally written, and the diverse responses and reactions that it has produced. We identify some of the book's inadequacies and limitations,…

  7. The exocyclic amino group of adenine in Pt(II) and Pd(II) complexes: a critical comparison of the X-ray crystallographic structural data and gas phase calculations.

    PubMed

    Silaghi-Dumitrescu, Radu; Mihály, Béla; Mihály, Timea; Attia, Amr A A; Sanz Miguel, Pablo J; Lippert, Bernhard

    2017-03-17

    A detailed computational (DFT level of theory) study regarding the nature of the exocyclic amino group, N6H2, of the model nucleobase 9-methyladenine (9MeA) and its protonated (9MeAH(+)) and deprotonated forms (9MeA-H), free and metal-complexed, has been conducted. The metals are Pt(II) and Pd(II), bonded to nitrogen-containing co-ligands (NH3, dien, bpy), with N1, N6, and N7 being the metal-binding sites, individually or in different combinations. The results obtained from gas phase calculations are critically compared with X-ray crystallography data, whenever possible. In the majority of cases, there is good qualitative agreement between calculated and experimentally determined C6-N6 bond lengths, but calculated values always show a trend to larger values, by 0.02-0.08 Å. Both methods indicate, with few exceptions, a high degree of double-bond character of C6-N6, consistent with an essentially sp(2)-hybridized N6 atom. The shortest values for C6-N6 distances in X-ray crystal structures are around 1.30 Å. Exceptions refer to cases in which DFT calculations suggest the existence of a hydrogen bond with N6H2 acting as a H bond acceptor, hence a situation with N6 having undergone a substantial hybridization shift toward sp(3). Nevertheless, even in these cases the C6-N6 bond (1.392 Å) is still halfway between a typical C-N single bond (1.48 Å) and a typical C=N double bond (1.28 Å). This scenario is, however, not borne out by X-ray crystallographic results, and is attributed to the absence of counter anions and solvent molecules in the calculated structures.

  8. Critical Information at Critical Moments

    ERIC Educational Resources Information Center

    Fierman, Ben; Thrower, Raymond H., Jr.

    2011-01-01

    On a daily basis, administrators are reminded of the potential, perhaps the likelihood, of violence or natural crises on their campuses. Comprehensive studies have been conducted and point to recommendations and best practices for planning, preparing, responding to, and recovering from critical incidents. The International Association of Campus…

  9. Generic criticality safety issues

    SciTech Connect

    Hively, L.M.

    1991-01-01

    An independent group has been designated by Martin Marietta Energy Systems, Inc., (MMES) to internally review Safety Analysis Reports for Packaging (SARPs) that describe containers for shipment of radioactive material. This group is called the Energy Systems Independent Review Group (ESIRG), reporting to the MMES Transportation Safety Manager as part of a central staff function. The ESIRG focus is Y-12 Plant packages, with additional review responsibilities for the Paducah Tiger UF{sub 6} overpack and 6M package. Review questions are posed directly to the SARP preparers. This paper addresses three generic issues that arose during the ESIRG criticality reviews: analysis tools, uncertainties in results, and resulting (finite) probability of criticality. 6 refs., 1 tab.

  10. 75 FR 11918 - Hewlett Pachard Company, Business Critical Systems, Mission Critical Business Software Division...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-12

    ... Business Software Division, Openvms Operating System Development Group, Including Employees Working Off... Company, Business Critical Systems, Mission Critical Business Software Division, Openvms Operating System... Software Division, OpenVMS Operating System Development Group, including employees working off site in New...

  11. Estimation of specific absorbed fractions for selected organs due to photons emitted by activity deposited in the human respiratory tract using ICRP/ICRU male voxel phantom in FLUKA.

    PubMed

    Patni, H K; Akar, D K; Nadar, M Y; Ghare, V P; Rao, D D; Sarkar, P K

    2013-01-01

    The ICRP/ICRU adult male reference voxel phantom incorporated in Monte Carlo code FLUKA is used for estimating specific absorbed fractions (SAFs) for photons due to the presence of internal radioactive contamination in the human respiratory tract (RT). The compartments of the RT, i.e. extrathoracic (ET1 and ET2) and thoracic (bronchi, bronchioles, alveolar interstitial) regions, lymph nodes of both regions and lungs are considered as the source organs. The nine organs having high tissue weighting factors such as colon, lungs, stomach wall, breast, testis, urinary bladder, oesophagus, liver and thyroid and the compartments of the RT are considered as target organs. Eleven photon energies in the range of 15 keV to 4 MeV are considered for each source organ and the computed SAF values are presented in the form of tables. For the target organs in the proximity of the source organ including the source organ itself, the SAF values are relatively higher and decrease with increase in energy. As the distance between source and target organ increases, SAF values increase with energy and reach maxima depending on the position of the target organ with respect to the source organ. The SAF values are relatively higher for the target organs with smaller masses. Large deviations are seen in computed SAF values from the existing MIRD phantom data for most of the organs. These estimated SAF values play an important role in the estimation of equivalent dose to various target organs of a worker due to intake by inhalation pathway.

  12. Group Processes in Experiential Training Groups in Botswana

    ERIC Educational Resources Information Center

    Nitza, Amy

    2011-01-01

    While group counseling has the potential to be an effective form of intervention in sub-Saharan Africa, research on group processes that would help guide group interventions in the region is scarce. This study investigated therapeutic factors and group climate in experiential training groups in Botswana. The Critical Incident Questionnaire (CIQ;…

  13. Critical Thinking: Implications for Research.

    ERIC Educational Resources Information Center

    Craver, Kathleen W.

    1989-01-01

    Synthesizes critical thinking research in four areas--reading, writing, group interactions, and speaking--and discusses the implications of those studies for library information science research. The potential for employing critical thinking strategies in bibliographic instruction and the need for library science educators to initiate their own…

  14. Minimum Critical Values Study

    SciTech Connect

    Fox, P.B.

    2005-07-11

    This report provides minimum critical values for various 30-cm water-reflected uranium and plutonium oxide and nitrate aqueous mixtures as calculated by the SCALE CSAS1X sequence using the 238-group ENDF/B-V neutron cross-section library. The minimum values were determined through parametric searches in one-dimensional geometry. The calculations have been performed to obtain the minimum values: critical volume and mass for spheres, critical radius for cylinders, critical thickness for slabs, and minimum critical concentration (infinite geometry) for the following homogeneous mixtures: (1) UO{sub 2}-H{sub 2}O for 3, 4, 5, 20, and 100 wt % {sup 235}U; (2) UNH for 3, 4, 5, 20, and 100 wt % {sup 235}U; (3) PuO{sub 2}-H{sub 2}O for 100/0/0, 95/5/0, 90/5/5, 80/10/10, and 71/17/11/1 wt % of {sup 239}Pu/{sup 240}Pu/{sup 241}Pu(/{sup 242}Pu); and (4) PuNH for 100/0/0, 95/5/0, 90/5/5, 80/10/10, and 71/17/11/1 wt % of {sup 239}Pu/{sup 240}Pu/{sup 241}Pu(/{sup 242}Pu). All bounding surfaces were fully reflected by 30 cm of H{sub 2}O.

  15. Critical dynamics in mixtures

    NASA Astrophysics Data System (ADS)

    Folk, R.; Moser, G.

    1998-11-01

    We derive the nonasymptotic expressions for the frequency- and temperature-dependent sound velocity and sound absorption near a critical point in a mixture within renormalization group theory in one-loop order. The dynamic model considered is an extension of the corresponding model for pure fluids including concentration fluctuations. The theoretical result for the complex sound velocity is the same as at consolute points and gas-liquid critical points reflecting universality. Differences observed in the experiments at the two critical points mentioned are due to the different behavior of the sound velocity at Tc, which is finite in mixtures and zero in pure fluids, as well as due to nonasymptotic effects. Near the consolute point we compare our result with the phenomenological theory of Ferrell and Bhattacharjee [Phys. Rev. B 24, 4095 (1981); Phys. Rev. A 31, 1788 (1985)] and near the gas-liquid critical point with experiments in the 3He-4He mixture. A genuine dynamic parameter not considered so far and related to the critical enhancement of the thermal conductivity appears in the nonasymptotic expressions of the transport coefficients and the complex sound velocity. All nonuniversal background parameters of the complex sound velocity are fixed by a comparison of the corresponding theoretical expressions for the transport coefficients with experiments.

  16. Impact of reduced dose limits on NRC licensed activities. Major issues in the implementation of ICRP/NCRP dose limit recommendations: Final report

    SciTech Connect

    Meinhold, C.B.

    1995-05-01

    This report summarizes information required to estimate, at least qualitatively, the potential impacts of reducing occupational dose limits below those given in 10 CFR 20 (Revised). For this study, a questionnaire was developed and widely distributed to the radiation protection community. The resulting data together with data from existing surveys and sources were used to estimate the impact of three dose-limit options; 10 mSv yr{sup {minus}1} (1 rem yr{sup {minus}1}), 20 mSv yr{sup {minus}1} (2 rem yr{sup {minus}1}), and a combination of an annual limit of 50 mSv yr{sup {minus}1} (5 rem yr{sup {minus}1}) coupled with a cumulative limit, in rem, equal to age in years. Due to the somewhat small number of responses and the lack of data in some specific areas, a working committee of radiation protection experts from a variety of licensees was employed to ensure the exposure data were representative. The following overall conclusions were reached: (1) although 10 mSv yr{sup {minus}1} is a reasonable limit for many licensees, such a limit could be extraordinarily difficult to achieve and potentially destructive to the continued operation of some licensees, such as nuclear power, fuel fabrication, and medicine; (2) twenty mSv yr{sup {minus}1} as a limit is possible for some of these groups, but for others it would prove difficult. (3) fifty mSv yr{sup {minus}1} and age in 10s of mSv appear reasonable for all licensees, both in terms of the lifetime risk of cancer and severe genetic effects to the most highly exposed workers, and the practicality of operation.

  17. Horizon as critical phenomenon

    NASA Astrophysics Data System (ADS)

    Lee, Sung-Sik

    2016-09-01

    We show that renormalization group flow can be viewed as a gradual wave function collapse, where a quantum state associated with the action of field theory evolves toward a final state that describes an IR fixed point. The process of collapse is described by the radial evolution in the dual holographic theory. If the theory is in the same phase as the assumed IR fixed point, the initial state is smoothly projected to the final state. If in a different phase, the initial state undergoes a phase transition which in turn gives rise to a horizon in the bulk geometry. We demonstrate the connection between critical behavior and horizon in an example, by deriving the bulk metrics that emerge in various phases of the U( N ) vector model in the large N limit based on the holographic dual constructed from quantum renormalization group. The gapped phase exhibits a geometry that smoothly ends at a finite proper distance in the radial direction. The geometric distance in the radial direction measures a complexity: the depth of renormalization group transformation that is needed to project the generally entangled UV state to a direct product state in the IR. For gapless states, entanglement persistently spreads out to larger length scales, and the initial state can not be projected to the direct product state. The obstruction to smooth projection at charge neutral point manifests itself as the long throat in the anti-de Sitter space. The Poincare horizon at infinity marks the critical point which exhibits a divergent length scale in the spread of entanglement. For the gapless states with non-zero chemical potential, the bulk space becomes the Lifshitz geometry with the dynamical critical exponent two. The identification of horizon as critical point may provide an explanation for the universality of horizon. We also discuss the structure of the bulk tensor network that emerges from the quantum renormalization group.

  18. [The critical scientists' voice].

    PubMed

    Lewgoy, F

    2000-01-01

    The intricate debate over genetically modified organisms (GMOs) involves powerful economic interests, as well as ethical, legal, emotional and scientific aspects, some of which are dealt with in this paper.(It is possible to identify two main groups of scientists across the GMOs divide: the triumphalist and the critical group.) Scientists in the triumphalist group state that GMOs and their derivatives are safe for the environment and do not offer health hazards any more than similar, non-genetically modified, products. This view is disputed by the critical scientists, who are prompted by the scarcity of studies on the environmental impacts and toxicity of GMOs, and who point out flaws in tests performed by the same companies which hold the patents. They are also critical of the current state of the process of gene transference, lacking accuracy, a fact which, coupled with the scant knowledge available about 97% of the genome functions, may produce unforseeable effects with risks for the environment and public health yet to be assessed. Examples of such effects are: the transference of alien genes [??] to other species, the emergence of toxins, the creation of new viruses, the impacts on beneficial insects and on biodiversity in general.

  19. Interpersonal criticism and the clergy.

    PubMed

    Garner, Randy

    2013-03-01

    Though well-crafted criticism can provide valuable information for the recipient, the abundance of literature finds that criticism is overwhelmingly viewed negatively. The consequences of adverse interpersonal criticism were assessed by a focus group of randomly selected clergy members from a large ministerial alliance. Collectively the focus group revealed that interpersonal criticism can have deleterious vocational, psychological, and health consequence for those in the ministry. Clergy reported that criticism from parishioners, the public, denominational officials, and others adversely affect interpersonal relationships and can lead to stress, burnout, and early departure from the ministry. The participants indicated that current training and resources were inadequate to deal with the issue and further denominational support and seminary education was necessary.

  20. Relative Critical Points

    NASA Astrophysics Data System (ADS)

    Lewis, Debra

    2013-05-01

    Relative equilibria of Lagrangian and Hamiltonian systems with symmetry are critical points of appropriate scalar functions parametrized by the Lie algebra (or its dual) of the symmetry group. Setting aside the structures - symplectic, Poisson, or variational - generating dynamical systems from such functions highlights the common features of their construction and analysis, and supports the construction of analogous functions in non-Hamiltonian settings. If the symmetry group is nonabelian, the functions are invariant only with respect to the isotropy subgroup of the given parameter value. Replacing the parametrized family of functions with a single function on the product manifold and extending the action using the (co)adjoint action on the algebra or its dual yields a fully invariant function. An invariant map can be used to reverse the usual perspective: rather than selecting a parametrized family of functions and finding their critical points, conditions under which functions will be critical on specific orbits, typically distinguished by isotropy class, can be derived. This strategy is illustrated using several well-known mechanical systems - the Lagrange top, the double spherical pendulum, the free rigid body, and the Riemann ellipsoids - and generalizations of these systems.

  1. Critical Pedagogy for Critical Mathematics Education

    ERIC Educational Resources Information Center

    Tutak, Fatma Aslan; Bondy, Elizabeth; Adams, Thomasenia L.

    2011-01-01

    This article provides a brief introduction to critical pedagogy and further discussion on critical mathematics education. Critical mathematics education enables students to read the world with mathematics. Three emerging domains of mathematics education related to critical mathematics education are discussed in this manuscript: ethnomathematics,…

  2. Outcomes in adult critically Ill cancer patients with and without neutropenia: a systematic review and meta-analysis of the Groupe de Recherche en Réanimation Respiratoire du patient d'Onco-Hématologie (GRRR-OH)

    PubMed Central

    Bourmaud, Aurélie; Azoulay, Elie; Mokart, Djamel; Darmon, Michael

    2017-01-01

    PURPOSE Whether neutropenia has an impact on the mortality of critically ill cancer patients remains controversial, yet it is widely used as an admission criterion and prognostic factor. METHODS Systematic review and meta-analysis. Studies on adult cancer patients and intensive care units were searched on PubMed and Cochrane databases (2005-2015). Summary estimates of mortality risk differences were calculated using the random-effects model. RESULTS Among the 1,528 citations identified, 38 studies reporting on 6,054 patients (2,097 neutropenic patients) were included. Median mortality across the studies was 54% [45–64], with unadjusted mortality in neutropenic and non-neutropenic critically ill patients of 60% [53–74] and 47% [41–68], respectively. Overall, neutropenia was associated with a 10% increased mortality risk (6%-14%; I2 = 50%). The admission period was not associated with how neutropenia affected mortality. Mortality significantly dropped throughout the study decade [−11% (−13.5 to −8.4)]. This mortality drop was observed in non-neutropenic patients [−12.1% (−15.2 to −9.0)] but not in neutropenic patients [−3.8% (−8.1 to +5.6)]. Sensitivity analyses disclosed no differences in underlying malignancy, mechanical ventilation use, or Granulocyte-colony stimulating factor use. Seven studies allowed the adjustment of severity results (1,350 patients). Although pooled risk difference estimates were similar to non-adjusted results, there was no significant impact of neutropenia on mortality (risk difference of mortality, 9%; 95% CI, −15 to +33) CONCLUSION Although the unadjusted mortality of neutropenic patients was 11% higher, this effect disappeared when adjusted for severity. Therefore, when cancer patients become critically ill, neutropenia cannot be considered as a decision-making criterion. PMID:27661125

  3. The Effect of Critical Comparisons upon Children's Drawings

    ERIC Educational Resources Information Center

    Rosenstiel, Anne K.; Gardner, Howard

    1977-01-01

    Compares the value of constructive criticism for older and younger children's artwork. Examines the effect that criticism has upon both age groups to learn whether the criticism is well received or damaging to further student effort. (Author/RK)

  4. Chronically Critically Ill Patients

    PubMed Central

    Douglas, Sara L.; Daly, Barbara J.; Kelley, Carol Genet; O’Toole, Elizabeth; Montenegro, Hugo

    2007-01-01

    Background Chronically critically ill patients often have high costs of care and poor outcomes and thus might benefit from a disease management program. Objectives To evaluate how adding a disease management program to the usual care system affects outcomes after discharge from the hospital (mortality, health-related quality of life, resource use) in chronically critically ill patients. Methods In a prospective experimental design, 335 intensive care patients who received more than 3 days of mechanical ventilation at a university medical center were recruited. For 8 weeks after discharge, advanced practice nurses provided an intervention that focused on case management and interdisciplinary communication to patients in the experimental group. Results A total of 74.0% of the patients survived and completed the study. Significant predictors of death were age (P = .001), duration of mechanical ventilation (P = .001), and history of diabetes (P = .04). The disease management program did not have a significant impact on health-related quality of life; however, a greater percentage of patients in the experimental group than in the control group had “improved” physical health-related quality of life at the end of the intervention period (P = .02). The only significant effect of the intervention was a reduction in the number of days of hospital readmission and thus a reduction in charges associated with readmission. Conclusion The intervention was not associated with significant changes in any outcomes other than duration of readmission, but the supportive care coordination program could be provided without increasing overall charges. PMID:17724242

  5. Group Capability Model

    NASA Technical Reports Server (NTRS)

    Olejarski, Michael; Appleton, Amy; Deltorchio, Stephen

    2009-01-01

    The Group Capability Model (GCM) is a software tool that allows an organization, from first line management to senior executive, to monitor and track the health (capability) of various groups in performing their contractual obligations. GCM calculates a Group Capability Index (GCI) by comparing actual head counts, certifications, and/or skills within a group. The model can also be used to simulate the effects of employee usage, training, and attrition on the GCI. A universal tool and common method was required due to the high risk of losing skills necessary to complete the Space Shuttle Program and meet the needs of the Constellation Program. During this transition from one space vehicle to another, the uncertainty among the critical skilled workforce is high and attrition has the potential to be unmanageable. GCM allows managers to establish requirements for their group in the form of head counts, certification requirements, or skills requirements. GCM then calculates a Group Capability Index (GCI), where a score of 1 indicates that the group is at the appropriate level; anything less than 1 indicates a potential for improvement. This shows the health of a group, both currently and over time. GCM accepts as input head count, certification needs, critical needs, competency needs, and competency critical needs. In addition, team members are categorized by years of experience, percentage of contribution, ex-members and their skills, availability, function, and in-work requirements. Outputs are several reports, including actual vs. required head count, actual vs. required certificates, CGI change over time (by month), and more. The program stores historical data for summary and historical reporting, which is done via an Excel spreadsheet that is color-coded to show health statistics at a glance. GCM has provided the Shuttle Ground Processing team with a quantifiable, repeatable approach to assessing and managing the skills in their organization. They now have a common

  6. A Canadian Critical Care Trials Group project in collaboration with the international forum for acute care trialists - Collaborative H1N1 Adjuvant Treatment pilot trial (CHAT): study protocol and design of a randomized controlled trial

    PubMed Central

    2011-01-01

    Background Swine origin influenza A/H1N1 infection (H1N1) emerged in early 2009 and rapidly spread to humans. For most infected individuals, symptoms were mild and self-limited; however, a small number developed a more severe clinical syndrome characterized by profound respiratory failure with hospital mortality ranging from 10 to 30%. While supportive care and neuraminidase inhibitors are the main treatment for influenza, data from observational and interventional studies suggest that the course of influenza can be favorably influenced by agents not classically considered as influenza treatments. Multiple observational studies have suggested that HMGCoA reductase inhibitors (statins) can exert a class effect in attenuating inflammation. The Collaborative H1N1 Adjuvant Treatment (CHAT) Pilot Trial sought to investigate the feasibility of conducting a trial during a global pandemic in critically ill patients with H1N1 with the goal of informing the design of a larger trial powered to determine impact of statins on important outcomes. Methods/Design A multi-national, pilot randomized controlled trial (RCT) of once daily enteral rosuvastatin versus matched placebo administered for 14 days for the treatment of critically ill patients with suspected, probable or confirmed H1N1 infection. We propose to randomize 80 critically ill adults with a moderate to high index of suspicion for H1N1 infection who require mechanical ventilation and have received antiviral therapy for ≤ 72 hours. Site investigators, research coordinators and clinical pharmacists will be blinded to treatment assignment. Only research pharmacy staff will be aware of treatment assignment. We propose several approaches to informed consent including a priori consent from the substitute decision maker (SDM), waived and deferred consent. The primary outcome of the CHAT trial is the proportion of eligible patients enrolled in the study. Secondary outcomes will evaluate adherence to medication administration

  7. The Pressure Group Cooker.

    ERIC Educational Resources Information Center

    Graves, Bill

    1992-01-01

    Administrators across the nation have encountered vigorous challenges against textbooks, practices, and procedures that critics find laden with occult and New Age values. Attacks are becoming more aggressive, better organized, and well financed. This article and accompanying sidebars discuss pressure group tactics and ways to counter them. The…

  8. Dimensions of Group Interaction

    ERIC Educational Resources Information Center

    Dawidowicz, Paula

    2008-01-01

    The correlation between positive and negative group interactions and one or another of individuals' attitudes or characteristics--moral development, critical thinking, resilience, and self efficacy--has been examined previously. However, no systemic examination of individuals' development of patterns of these characteristics and those patterns'…

  9. Acute kidney injury in critically ill patients with haematological malignancies: results of a multicentre cohort study from the Groupe de Recherche en Réanimation Respiratoire en Onco-Hématologie

    PubMed Central

    Darmon, Michael; Vincent, François; Canet, Emmanuel; Mokart, Djamel; Pène, Frédéric; Kouatchet, Achille; Mayaux, Julien; Nyunga, Martine; Bruneel, Fabrice; Rabbat, Antoine; Lebert, Christine; Perez, Pierre; Renault, Anne; Meert, Anne-Pascale; Benoit, Dominique; Hamidfar, Rebecca; Jourdain, Mercé; Schlemmer, Benoit; Chevret, Sylvie; Lemiale, Virginie; Azoulay, Elie

    2015-01-01

    Background Cancer patients are at high risk for acute kidney injury (AKI), which is associated with high morbidity and mortality. We sought to appraise the incidence, risk factors, and outcome of AKI in a large multicentre cohort study of critically ill patients with haematological malignancies. Methods We used a retrospective analysis of a prospectively collected database. The study was carried out in 17 university or university-affiliated centres in France and Belgium between 2010 and 2012. AKI was defined according to the Acute Kidney Injury Network (AKIN) definition. Results Of the 1011 patients admitted into the intensive care unit (ICU) during the study period, 1009 were included in this study. According to the AKIN definition, 671 patients (66.5%) developed an AKI during their ICU stay, of which 258 patients (38.4%) were AKI stage 1, 75 patients (11.2%) AKI stage 2 and 338 patients (50.4%) AKI stage 3. After adjustment for confounders, main adverse risk factors of AKI were older age, severity [non-renal Sequential Organ Failure Assessment (SOFA)], history of hypertension, tumour lysis syndrome, exposure to nephrotoxic agents and myeloma. Hospital mortality was 44.3% in patients with AKI and 25.4% in patients without AKI (P < 0.0001). After adjustment for confounders, AKI was independently associated with hospital mortality [OR 1.65 (95% CI 1.19–2.29)]. Overall, 271 patients required renal replacement therapy (RRT), of whom 57.2% died during their hospital stay as compared with 31.2% (P < 0.0001) in those not requiring RRT. Conclusion Two-thirds of critically ill patients with haematological malignancies developed AKI. Hospital mortality in this population of patients developing AKI or requiring RRT is close to that in general ICU population. PMID:26597921

  10. Outcomes of critically ill patients with hematologic malignancies: prospective multicenter data from France and Belgium--a groupe de recherche respiratoire en réanimation onco-hématologique study.

    PubMed

    Azoulay, Elie; Mokart, Djamel; Pène, Frédéric; Lambert, Jérôme; Kouatchet, Achille; Mayaux, Julien; Vincent, François; Nyunga, Martine; Bruneel, Fabrice; Laisne, Louise-Marie; Rabbat, Antoine; Lebert, Christine; Perez, Pierre; Chaize, Marine; Renault, Anne; Meert, Anne-Pascale; Benoit, Dominique; Hamidfar, Rebecca; Jourdain, Mercé; Darmon, Michael; Schlemmer, Benoit; Chevret, Sylvie; Lemiale, Virginie

    2013-08-01

    PURPOSE Patients with hematologic malignancies are increasingly admitted to the intensive care unit (ICU) when life-threatening events occur. We sought to report outcomes and prognostic factors in these patients. PATIENTS AND METHODS Ours was a prospective, multicenter cohort study of critically ill patients with hematologic malignancies. Health-related quality of life (HRQOL) and disease status were collected after 3 to 6 months. Results Of the 1,011 patients, 38.2% had newly diagnosed malignancies, 23.1% were in remission, and 24.9% had received hematopoietic stem-cell transplantations (HSCT, including 145 allogeneic). ICU admission was mostly required for acute respiratory failure (62.5%) and/or shock (42.3%). On day1, 733 patients (72.5%) received life-supporting interventions. Hospital, day-90, and 1-year survival rates were 60.7%, 52.5%, and 43.3%, respectively. By multivariate analysis, cancer remission and time to ICU admission less than 24 hours were associated with better hospital survival. Poor performance status, Charlson comorbidity index, allogeneic HSCT, organ dysfunction score, cardiac arrest, acute respiratory failure, malignant organ infiltration, and invasive aspergillosis were associated with higher hospital mortality. Mechanical ventilation (47.9% of patients), vasoactive drugs (51.2%), and dialysis (25.9%) were associated with mortality rates of 60.5%, 57.5%, and 59.2%, respectively. On day 90, 80% of survivors had no HRQOL alterations (physical and mental health similar to that of the overall cancer population). After 6 months, 80% of survivors had no change in treatment intensity compared with similar patients not admitted to the ICU, and 80% were in remission. CONCLUSION Critically ill patients with hematologic malignancies have good survival, disease control, and post-ICU HRQOL. Earlier ICU admission is associated with better survival.

  11. Group X

    SciTech Connect

    Fields, Susannah

    2007-08-16

    This project is currently under contract for research through the Department of Homeland Security until 2011. The group I was responsible for studying has to remain confidential so as not to affect the current project. All dates, reference links and authors, and other distinguishing characteristics of the original group have been removed from this report. All references to the name of this group or the individual splinter groups has been changed to 'Group X'. I have been collecting texts from a variety of sources intended for the use of recruiting and radicalizing members for Group X splinter groups for the purpose of researching the motivation and intent of leaders of those groups and their influence over the likelihood of group radicalization. This work included visiting many Group X websites to find information on splinter group leaders and finding their statements to new and old members. This proved difficult because the splinter groups of Group X are united in beliefs, but differ in public opinion. They are eager to tear each other down, prove their superiority, and yet remain anonymous. After a few weeks of intense searching, a list of eight recruiting texts and eight radicalizing texts from a variety of Group X leaders were compiled.

  12. Critical thinking in nursing: an integrated review.

    PubMed

    Brunt, Barbara A

    2005-01-01

    Critical thinking skills are essential to function in today's complex health care environment and to ensure continuing competence for the future. This article provides a review of various definitions and research studies related to critical thinking. Educators and researchers need to clearly define critical thinking, because there has been wide variation in definitions and descriptions of critical thinking. Research studies have shown inconsistent findings, and many have used a one-group pretest-posttest design over a single course or during the length of a nursing program. Studies have not shown an association between critical thinking and competence; rigorous research studies are needed to understand the process of critical thinking.

  13. Distance Education and Open Learning in Sub-Saharan Africa: Criteria and Conditions for Quality and Critical Success Factor-- Working Group on Distance Education and Open Learning. A Survey of Policy and Practice. Final Report

    ERIC Educational Resources Information Center

    Commonwealth of Learning, 2004

    2004-01-01

    Both of these "Surveys of policy and practice" were conducted on behalf of COL by the South African Institute for Distance Education (SAIDE) as part of COL's partnership agreement with the Association for the Development of Education in Africa (ADEA) Working Group on Distance Education and Open Learning. The first report identifies…

  14. Group Flow and Group Genius

    ERIC Educational Resources Information Center

    Sawyer, Keith

    2015-01-01

    Keith Sawyer views the spontaneous collaboration of group creativity and improvisation actions as "group flow," which organizations can use to function at optimum levels. Sawyer establishes ideal conditions for group flow: group goals, close listening, complete concentration, being in control, blending egos, equal participation, knowing…

  15. Appraisal of literature reviews on end-of-life care for minority ethnic groups in the UK and a critical comparison with policy recommendations from the UK end-of-life care strategy

    PubMed Central

    2011-01-01

    Background Evidence of low end-of-life (EoL) care service use by minority ethnic groups in the UK has given rise to a body of research and a number of reviews of the literature. This article aims to review and evaluate literature reviews on minority ethnic groups and EoL care in the UK and assess their suitability as an evidence base for policy. Methods Systematic review. Searches were carried out in thirteen electronic databases, eight journals, reference lists, and grey literature. Reviews were included if they concerned minority ethnic groups and EoL care in the UK. Reviews were graded for quality and key themes identified. Results Thirteen reviews (2001-2009) met inclusion criteria. Seven took a systematic approach, of which four scored highly for methodological quality (a mean score of six, median seven). The majority of systematic reviews were therefore of a reasonable methodological quality. Most reviews were restricted by ethnic group, aspect of EoL care, or were broader reviews which reported relevant findings. Six key themes were identified. Conclusions A number of reviews were systematic and scored highly for methodological quality. These reviews provide a good reflection of the primary evidence and could be used to inform policy. The complexity and inter-relatedness of factors leading to low service use was recognised and reflected in reviews' recommendations for service improvement. Recommendations made in the UK End-of-Life Care Strategy were limited in comparison, and the Strategy's evidence base concerning minority ethnic groups was found to be narrow. Future policy should be embedded strongly in the evidence base to reflect the current literature and minimise bias. PMID:21635738

  16. Appraisal of literature reviews on end-of-life care for minority ethnic groups in the UK and a critical comparison with policy recommendations from the UK end-of-life care strategy.

    PubMed

    Evans, Natalie; Meñaca, Arantza; Andrew, Erin Vw; Koffman, Jonathan; Harding, Richard; Higginson, Irene J; Pool, Robert; Gysels, Marjolein

    2011-06-02

    Evidence of low end-of-life (EoL) care service use by minority ethnic groups in the UK has given rise to a body of research and a number of reviews of the literature. This article aims to review and evaluate literature reviews on minority ethnic groups and EoL care in the UK and assess their suitability as an evidence base for policy. Systematic review. Searches were carried out in thirteen electronic databases, eight journals, reference lists, and grey literature. Reviews were included if they concerned minority ethnic groups and EoL care in the UK. Reviews were graded for quality and key themes identified. Thirteen reviews (2001-2009) met inclusion criteria. Seven took a systematic approach, of which four scored highly for methodological quality (a mean score of six, median seven). The majority of systematic reviews were therefore of a reasonable methodological quality. Most reviews were restricted by ethnic group, aspect of EoL care, or were broader reviews which reported relevant findings. Six key themes were identified. A number of reviews were systematic and scored highly for methodological quality. These reviews provide a good reflection of the primary evidence and could be used to inform policy. The complexity and inter-relatedness of factors leading to low service use was recognised and reflected in reviews' recommendations for service improvement. Recommendations made in the UK End-of-Life Care Strategy were limited in comparison, and the Strategy's evidence base concerning minority ethnic groups was found to be narrow. Future policy should be embedded strongly in the evidence base to reflect the current literature and minimise bias.

  17. Critical Viewing: Stimulant to Critical Thinking.

    ERIC Educational Resources Information Center

    O'Reilly, Kevin; Splaine, John

    This document is intended to improve the critical viewing skills and increase the understanding and appreciation of what is viewed. Included are the chapters: (1) "Critical Thinking: The Parts of an Argument," intended to develop a process to help a person judge arguments in what is read, seen, and heard; (2) "Critical Viewing:…

  18. Isopermutation group

    SciTech Connect

    Muktibodh, A. S.

    2015-03-10

    The concept of ‘Isotopy’ as formulated by Ruggero Maria Santilli [1, 2, 3] plays a vital role in the development of Iso mathematics. Santilli defined iso-fields of characteristic zero. In this paper we extend this definition to define Iso-Galois fields [4] which are essentially of non-zero characteristic. Isotopically isomorphic realizations of a group define isopermutation group which gives a clear cut distinction between automorphic groups and isotopic groups.

  19. Home Groups.

    ERIC Educational Resources Information Center

    Stahler, Theresa M.

    All students enrolled in the entry level foundations course in the College of Education of Kutztown University (Pennsylvania) participate in home groups, a cooperative learning strategy. Each student is assigned to a five- or six-person home group on the first day of class. Although group placements are made on the basis of class lists, every…

  20. Hot Groups.

    ERIC Educational Resources Information Center

    Vail, Kathleen

    1996-01-01

    Collaborators sparked by creative ideas and obsessed by a common task may not realize they're part of a "hot group"--a term coined by business professors Harold J. Leavitt and Jean Lipman-Blumen. Spawned by group decision making and employee empowerment, hot groups can flourish in education settings. They're typically small, short lived,…

  1. Crossover critical phenomena in fluids

    NASA Astrophysics Data System (ADS)

    Kostrowicka Wyczalkowska, Anna Judyta

    In fluids the effects of critical density fluctuations remain significant over a large range of temperatures and densities. The nonanalytical behavior observed in real fluids in the vicinity of the critical point is well described by renormalization-group theory. This theory accounts properly for the influence of the critical fluctuations in density which are entirely neglected by the classical equations. Specifically, fluids asymptotically close to the critical point belong to the universality class of the 3-dimensional Ising model and their behavior near the critical point is governed by scaling laws with critical exponents appropriate for this universality class. The validity of the asymptotic power laws is, however, restricted to a very small region near the critical point. An approach to deal with the nonasymptotic behavior of fluids including the crossover from Ising behavior in the immediate vicinity of the critical point to classical behavior far away from the critical point has been developed by Chen and coworkers and is further improved in this thesis. This approach is based on earlier work of Nicoll and coworkers and it leads to a transformation of a classical Landau expansion to incorporate the effects of critical fluctuations. Here we show how this transformation applies to real fluids: water and sulfurhexafluoride. Nevertheless, even such a crossover Landau expansion still fails to make a connection with the behavior of the fluid very far away from the critical point like the ideal-gas limit at low densities. We demonstrate how a procedure, earlier developed to include the effects of critical fluctuations into a classical Landau expansion of the Helmholtz-energy density, can also be applied to a closed-form classical equation of state like the equation of van der Waals. One of the consequences of accounting for the presence of the critical fluctuations is a shift in the location of the critical point. The resulting equation incorporates the

  2. Galaxy groups

    SciTech Connect

    Brent Tully, R.

    2015-02-01

    Galaxy groups can be characterized by the radius of decoupling from cosmic expansion, the radius of the caustic of second turnaround, and the velocity dispersion of galaxies within this latter radius. These parameters can be a challenge to measure, especially for small groups with few members. In this study, results are gathered pertaining to particularly well-studied groups over four decades in group mass. Scaling relations anticipated from theory are demonstrated and coefficients of the relationships are specified. There is an update of the relationship between light and mass for groups, confirming that groups with mass of a few times 10{sup 12}M{sub ⊙} are the most lit up while groups with more and less mass are darker. It is demonstrated that there is an interesting one-to-one correlation between the number of dwarf satellites in a group and the group mass. There is the suggestion that small variations in the slope of the luminosity function in groups are caused by the degree of depletion of intermediate luminosity systems rather than variations in the number per unit mass of dwarfs. Finally, returning to the characteristic radii of groups, the ratio of first to second turnaround depends on the dark matter and dark energy content of the universe and a crude estimate can be made from the current observations of Ω{sub matter}∼0.15 in a flat topology, with a 68% probability of being less than 0.44.

  3. Critical Materials Institute

    ScienceCinema

    Alex King

    2016-07-12

    Ames Laboratory Director Alex King talks about the goals of the Critical Materials Institute in diversifying the supply of critical materials, developing substitute materials, developing tools and techniques for recycling critical materials, and forecasting materials needs to avoid future shortages.

  4. Critical Materials Institute

    SciTech Connect

    Alex King

    2013-01-09

    Ames Laboratory Director Alex King talks about the goals of the Critical Materials Institute in diversifying the supply of critical materials, developing substitute materials, developing tools and techniques for recycling critical materials, and forecasting materials needs to avoid future shortages.

  5. GROUP INEQUALITY

    PubMed Central

    Bowles, Samuel; Loury, Glenn C.; Sethi, Rajiv

    2014-01-01

    We explore the combined effect of segregation in social networks, peer effects, and the relative size of a historically disadvantaged group on the incentives to invest in market-rewarded skills and the dynamics of inequality between social groups. We identify conditions under which group inequality will persist in the absence of differences in ability, credit constraints, or labor market discrimination. Under these conditions, group inequality may be amplified even if initial group differences are negligible. Increases in social integration may destabilize an unequal state and make group equality possible, but the distributional and human capital effects of this depend on the demographic composition of the population. When the size of the initially disadvantaged group is sufficiently small, integration can lower the long-run costs of human capital investment in both groups and result in an increase the aggregate skill share. In contrast, when the initially disadvantaged group is large, integration can induce a fall in the aggregate skill share as the costs of human capital investment rise in both groups. We consider applications to concrete cases and policy implications. PMID:25554727

  6. Whitehead Groups of Spinor Groups

    NASA Astrophysics Data System (ADS)

    Monastyrnyĭ, A. P.; Yanchevskiĭ, V. I.

    1991-02-01

    The Whitehead groups of spinor groups are studied. The known Kneser-Tits conjecture for spinor groups is reduced to a spinor analogue of the Tannaka-Artin problem, namely, to the question of whether the group K1Spin(D), where D is a division ring of exponent 2 , is trivial. A counterexample to the Kneser-Tits problem is constructed in the class of spinor groups. The group K1Spin(D) is computed. The stability of the Whitehead groups of spinor groups under purely transcendental extensions of the ground field is established. The R-equivalence on the k-points of spinor groups and the weak approximation problem are considered. The study of spinor group completes the study of the Whitehead groups of algebraic groups of classical type, that was started in studying reduced K-theory (V.P. Platonov) and was continued for reduced unitary K-theory (V.I. Yanchevskiĭ) and Hermitian K-theory (Platonov and Yanchevskiĭ). Bibliography: 50 titles.

  7. Nuclear criticality safety guide

    SciTech Connect

    Pruvost, N.L.; Paxton, H.C.

    1996-09-01

    This technical reference document cites information related to nuclear criticality safety principles, experience, and practice. The document also provides general guidance for criticality safety personnel and regulators.

  8. Coping with criticism and praise.

    PubMed

    Esdale, Lynn; Jahoda, Andrew; Pert, Carol

    2015-05-01

    Through experiencing stigma and discrimination, people with intellectual disability may become more sensitive to criticism from others and be less likely to believe praise. This study compared how people with and without intellectual disability viewed praise and criticism, using a vignette task developed for the study. Participants were asked to imagine someone saying something praiseworthy or critical and were then asked about their emotions, beliefs, and thoughts. People with intellectual disability were more likely to believe and be distressed by criticism. Contrary to predictions, this group were also more likely to believe praise and experience positive affect. The results suggest that the self-perceptions of people with intellectual disabilities is more dynamic and reliant on the views of others.

  9. Productive criticism. Part 1: Criticism that works.

    PubMed

    Weisinger, H D

    1995-01-01

    Criticism affects almost all aspects of your job: the quality of work you do, how you feel about your performance, and your relationships with your boss, coworkers, and subordinates. Used productively, criticism is a powerful tool that helps you improve your work, enhance your working relationships, increase your job satisfaction, and achieve better overall results. Improperly used, it impedes performance, demoralizes you, discourages you from wanting to try again, and creates friction in the workplace. In short, the ability to give and take criticism significantly determines how well you do on the job. In Part I, we will examine the traditional negative approach to criticism and develop new management tools to turn criticism into an opportunity for growth and education. By explaining new evaluation and communication techniques, we will show the reader how to use productive criticism to increase job performance and satisfaction.

  10. Critical diagnoses (critical values) in anatomic pathology.

    PubMed

    Silverman, Jan F; Fletcher, Christopher D M; Frable, William J; Goldblum, John R; Pereira, Telma C; Swanson, Paul E

    2006-08-01

    Similar to critical values in clinical pathology, occasional diagnoses in surgical pathology and cytology may require urgent contact of the physician to facilitate rapid intervention or treatment. However, there are no established critical value (critical diagnosis) guidelines in anatomic pathology. As discussed herein, the Association of Directors of Anatomic and Surgical Pathology (ADASP) believes that establishing anatomic pathology critical diagnosis guidelines represents a practice improvement and patient safety initiative. The ADASP also recognizes that a generic anatomic pathology critical diagnosis guideline such as this should only be used as a template because the list needs to be customized at each individual hospital after consultation with relevant clinical services. Based on surveys of the membership of the ADASP, this document provides examples of possible critical diagnoses in anatomic pathology.

  11. Critical diagnoses (critical values) in anatomic pathology.

    PubMed

    Silverman, Jan F

    2006-06-01

    Similar to critical values in clinical pathology, occasional diagnoses in surgical pathology and cytology may require urgent contact of the physician to facilitate rapid intervention or treatment. However, there are no established critical value (critical diagnosis) guidelines in anatomic pathology. As discussed herein, the Association of Directors of Anatomic and Surgical Pathology (ADASP) believes that establishing anatomic pathology critical diagnosis guidelines represents a practice improvement and patient safety initiative. ADASP also recognizes that a generic anatomic pathology critical diagnosis guideline such as this should be used only as a template because the list needs to be customized at each individual hospital following consultation with relevant clinical services. Based on surveys of the membership of the ADASP, this document provides examples of possible critical diagnoses in anatomic pathology.

  12. Critical diagnoses (critical values) in anatomic pathology.

    PubMed

    2006-07-01

    Similar to critical values in clinical pathology, occasional diagnoses in surgical pathology and cytology may require urgent contact of the physician to facilitate rapid intervention or treatment. However, there are no established critical value (critical diagnosis) guidelines in anatomic pathology. As discussed herein, the Association of Directors of Anatomic and Surgical Pathology (ADASP) believes that establishing anatomic pathology critical diagnosis guidelines represents a practice improvement and patient safety initiative. ADASP also recognizes that a generic anatomic pathology critical diagnosis guideline such as this should only be used as a template, because the list needs to be customized at each individual hospital after consultation with relevant clinical services. Based on surveys of the membership of the ADASP, this document provides examples of possible critical diagnoses in anatomic pathology.

  13. Group Theatre.

    ERIC Educational Resources Information Center

    Clark, Brian

    The group interpretation approach to theatre production is defined as a method that will lead to production of plays that will appeal to "all the layers of the conscious and unconscious mind." In practice, it means that the group will develop and use resources of the theatre that orthodox companies too often ignore. The first two chapters of this…

  14. To the Critics, the Spoils.

    ERIC Educational Resources Information Center

    Harris, Rick

    1995-01-01

    In a partnership between several tool companies and vocational high schools, students in construction technology classes give new products a fair and rigorous workout at a fraction of the cost of focus groups. The process allows companies to expose their products to students who, in turn, provide critical evaluation of the tools. (JOW)

  15. Lessons for Teaching Art Criticism.

    ERIC Educational Resources Information Center

    Barrett, Terry, Ed.; Clark, Gilbert, Ed.

    This collection of lessons is meant to be a practical guide to help teachers engage children in art criticism. The lessons generally follow a similar format. Most suggest an age group but may be modified for use with younger or older students. Several authors suggest variations and extensions for lessons that include studio activities. A broad…

  16. To the Critics, the Spoils.

    ERIC Educational Resources Information Center

    Harris, Rick

    1995-01-01

    In a partnership between several tool companies and vocational high schools, students in construction technology classes give new products a fair and rigorous workout at a fraction of the cost of focus groups. The process allows companies to expose their products to students who, in turn, provide critical evaluation of the tools. (JOW)

  17. Elementary School Literacy: Critical Issues.

    ERIC Educational Resources Information Center

    Dreher, Mariam Jean, Ed.; Slater, Wayne H., Ed.

    Providing a thorough grounding on important topics in elementary school literacy for experienced teachers and graduate students early in their programs, this book addresses a number of critical issues such as grouping and reading instruction, emergent literacy, learning to read and write with at-risk children, developing vocabulary, learning in…

  18. Pluralistic Approaches to Art Criticism.

    ERIC Educational Resources Information Center

    Blandy, Doug, Ed.; Congdon, Kristin G., Ed.

    Contributors to this anthology analyze the contemporary academic methods for critiquing art and suggest new ways that might further the understandings of art created by diverse individuals and groups. Essays are organized into three sections. Part 1, "Changes and Extensions in Critical Approaches" includes essays: (1) "Beyond Universalism in Art…

  19. Notions of Criticality: Singaporean Teachers' Perspectives of Critical Thinking in Social Studies

    ERIC Educational Resources Information Center

    Baildon, Mark C.; Sim, Jasmine B.-Y.

    2009-01-01

    In this article we explore the ways critical thinking is conceived by a group of Singaporean social studies teachers, what they see as its purposes as well as perceived constraints to critical thinking and teaching critical thinking in Singapore's schools. Using a case study research design and constant comparative method we analysed data from…

  20. Notions of Criticality: Singaporean Teachers' Perspectives of Critical Thinking in Social Studies

    ERIC Educational Resources Information Center

    Baildon, Mark C.; Sim, Jasmine B.-Y.

    2009-01-01

    In this article we explore the ways critical thinking is conceived by a group of Singaporean social studies teachers, what they see as its purposes as well as perceived constraints to critical thinking and teaching critical thinking in Singapore's schools. Using a case study research design and constant comparative method we analysed data from…

  1. Mild cognitive impairment (MCI) in medical practice: a critical review of the concept and new diagnostic procedure. Report of the MCI Working Group of the European Consortium on Alzheimer's Disease.

    PubMed

    Portet, F; Ousset, P J; Visser, P J; Frisoni, G B; Nobili, F; Scheltens, Ph; Vellas, B; Touchon, J

    2006-06-01

    Mild cognitive impairment (MCI) was proposed as a nosological entity referring to elderly people with mild cognitive deficit but no dementia. MCI is a heterogeneous clinical entity with multiple sources of heterogeneity. The concept of MCI was reviewed and a diagnostic procedure with three different stages was proposed by the European Consortium on Alzheimer's Disease Working Group on MCI. Firstly, MCI should correspond to cognitive complaints coming from the patients or their families; the reporting of a relative decline in cognitive functioning during the past year by a patient or informant; cognitive disorders as evidenced by clinical evaluation; absence of major repercussions on daily life; and absence of dementia. These criteria, similar to those defined during an international workshop in Stockholm, make it possible to identify an MCI syndrome, which is the first stage of the diagnostic procedure. Secondly, subtypes of MCI had to be recognised. Finally, the aetiopathogenic subtype could be identified. Identifying patients at a high risk for progression to dementia and establishing more specific and adapted therapeutic strategies at an early stage, together with more structured overall management, is made possible by the diagnostic procedure proposed.

  2. A Critical Humanist Curriculum

    ERIC Educational Resources Information Center

    Magill, Kevin; Rodriguez, Arturo

    2015-01-01

    This essay is a critical humanist discussion of curriculum; a departure from the technicist view of education [education meant to support a global capitalist economy] and an analysis of curriculum considering critical humanism, political economy and critical race theory among other modes of critical analysis and inquiry. Our discussion supports a…

  3. Critical Thinking Skills.

    ERIC Educational Resources Information Center

    Word's Worth: A Quarterly Newsletter of the Lifelong Learning Network, 1998

    1998-01-01

    This issue of a quarterly newsletter focuses on the theme of critical thinking skills. "Critical Thinking Skills: An Interview with Dr. Richard Paul" (Barbara Christopher) is the text of an interview in which the director of research at Sonoma State University's Center for Critical Thinking examines the meaning of critical thinking and…

  4. A Critical Humanist Curriculum

    ERIC Educational Resources Information Center

    Magill, Kevin; Rodriguez, Arturo

    2015-01-01

    This essay is a critical humanist discussion of curriculum; a departure from the technicist view of education [education meant to support a global capitalist economy] and an analysis of curriculum considering critical humanism, political economy and critical race theory among other modes of critical analysis and inquiry. Our discussion supports a…

  5. The challenges and outcomes of living donor kidney transplantation in pediatric and adolescent age group in a developing country: A critical analysis from a single center of north India

    PubMed Central

    Srivastava, Aneesh; Prabhakaran, Sandeep; Sureka, Sanjoy Kumar; Kapoor, Rakesh; Kumar, Anant; Sharma, R. K.; Prasad, Narayan; Ansari, M. S.

    2015-01-01

    Introduction: Renal transplantation is the treatment of choice for children with end-stage renal disease (ESRD). We evaluated the outcome of renal transplantation in the pediatric and adolescent age groups in the perspective of a developing country as compared with developed nations while highlighting the challenges we have faced in a pediatric transplant programme. Materials and Methods: Seventy live related pediatric and adolescent renal transplantations were reviewed retrospectively. Variables analyzed were etiology of ESRD, pre-transplant renal replacement modality, donor relationship, surgical complications, rejection episodes, immuno-suppression regimens, compliance to immunosuppression, graft survival and overall survival. Results: The cohort consisted of 13 (18%) female and 57 male (82%) recipients. The mean age was 14 ± 1.4 years. The etiology of ESRD was chronic glomerulonephritis (n = 43), chronic interstitial nephritis (n = 26) and Alport's syndrome (n = 1). Fifty-six (80%) children were on hemo-dialysis and 10 (14%) on peritoneal dialysis prior to transplantation. 80.5% and 61% patients were strictly compliant to immunosuppresant medications at 1 and 5 years. The 1, 3 and 5 year graft survival rates were 94.3%, 89.2% and 66.8%, respectively. The overall survival rates were 95.7%, 96.4% and 94.1% for 1, 3 and 5 years, respectively. Conclusions: The spectrum of etiology of ESRD differs in our patients from the west, with chronic glomerulonephritis being the most common etiology. Early graft survival is comparable, but the 5-year graft survival is clearly inferior as compared with developed countries. PMID:25624573

  6. Group Grammar

    ERIC Educational Resources Information Center

    Adams, Karen

    2015-01-01

    In this article Karen Adams demonstrates how to incorporate group grammar techniques into a classroom activity. In the activity, students practice using the target grammar to do something they naturally enjoy: learning about each other.

  7. Revalorizing the Critical Attitude for Critical Education

    ERIC Educational Resources Information Center

    Amsler, Sarah S.

    2011-01-01

    This article argues that at a moment of crisis in education, the defence of critical pedagogy is vitally important. However, it also suggests that such a defence should be more than a "cri de coeur" that asserts principles and methods of criticality against those of neoliberal or conservative education policy. Narratives of a totalising "crisis of…

  8. A Critical Look into Critical Pedagogy

    ERIC Educational Resources Information Center

    Pishghadam, Reza; Meidani, Elham Naji

    2012-01-01

    In line with postmodern philosophy, critical pedagogy has gained considerable importance and has become a valuable educational goal. The purpose of this study is to dig into the effects of critical pedagogy in a modernist educational system. To this aim, 15 Iranian university students were asked to write down their feelings at the end of a course…

  9. Critical Thinking and the Critical Person.

    ERIC Educational Resources Information Center

    Paul, Richard W.

    The paper's purpose is to clarify and develop some theoretical and practical implications of the concept of critical thinking, and the field of social studies is used as one example of the problem. The work of four leading critical theorists (Robert Ennis, Harvey Siegel, Michael Scriven, and R. S. Peters) is described and a distinction is made…

  10. A critical review of the research literature on Six Sigma, Lean and StuderGroup's Hardwiring Excellence in the United States: the need to demonstrate and communicate the effectiveness of transformation strategies in healthcare

    PubMed Central

    Vest, Joshua R; Gamm, Larry D

    2009-01-01

    Background U.S. healthcare organizations are confronted with numerous and varied transformational strategies promising improvements along all dimensions of quality and performance. This article examines the peer-reviewed literature from the U.S. for evidence of effectiveness among three current popular transformational strategies: Six Sigma, Lean/Toyota Production System, and Studer's Hardwiring Excellence. Methods The English language health, healthcare management, and organizational science literature (up to December 2007) indexed in Medline, Web of Science, ABI/Inform, Cochrane Library, CINAHL, and ERIC was reviewed for studies on the aforementioned transformation strategies in healthcare settings. Articles were included if they: appeared in a peer-reviewed journal; described a specific intervention; were not classified as a pilot study; provided quantitative data; and were not review articles. Nine references on Six Sigma, nine on Lean/Toyota Production System, and one on StuderGroup meet the study's eligibility criteria. Results The reviewed studies universally concluded the implementations of these transformation strategies were successful in improving a variety of healthcare related processes and outcomes. Additionally, the existing literature reflects a wide application of these transformation strategies in terms of both settings and problems. However, despite these positive features, the vast majority had methodological limitations that might undermine the validity of the results. Common features included: weak study designs, inappropriate analyses, and failures to rule out alternative hypotheses. Furthermore, frequently absent was any attention to changes in organizational culture or substantial evidence of lasting effects from these efforts. Conclusion Despite the current popularity of these strategies, few studies meet the inclusion criteria for this review. Furthermore, each could have been improved substantially in order to ensure the validity of the

  11. A critical review of the research literature on Six Sigma, Lean and StuderGroup's Hardwiring Excellence in the United States: the need to demonstrate and communicate the effectiveness of transformation strategies in healthcare.

    PubMed

    Vest, Joshua R; Gamm, Larry D

    2009-07-01

    U.S. healthcare organizations are confronted with numerous and varied transformational strategies promising improvements along all dimensions of quality and performance. This article examines the peer-reviewed literature from the U.S. for evidence of effectiveness among three current popular transformational strategies: Six Sigma, Lean/Toyota Production System, and Studer's Hardwiring Excellence. The English language health, healthcare management, and organizational science literature (up to December 2007) indexed in Medline, Web of Science, ABI/Inform, Cochrane Library, CINAHL, and ERIC was reviewed for studies on the aforementioned transformation strategies in healthcare settings. Articles were included if they: appeared in a peer-reviewed journal; described a specific intervention; were not classified as a pilot study; provided quantitative data; and were not review articles. Nine references on Six Sigma, nine on Lean/Toyota Production System, and one on StuderGroup meet the study's eligibility criteria. The reviewed studies universally concluded the implementations of these transformation strategies were successful in improving a variety of healthcare related processes and outcomes. Additionally, the existing literature reflects a wide application of these transformation strategies in terms of both settings and problems. However, despite these positive features, the vast majority had methodological limitations that might undermine the validity of the results. Common features included: weak study designs, inappropriate analyses, and failures to rule out alternative hypotheses. Furthermore, frequently absent was any attention to changes in organizational culture or substantial evidence of lasting effects from these efforts. Despite the current popularity of these strategies, few studies meet the inclusion criteria for this review. Furthermore, each could have been improved substantially in order to ensure the validity of the conclusions, demonstrate

  12. Being Critical of Criticality in the Brain

    PubMed Central

    Beggs, John M.; Timme, Nicholas

    2012-01-01

    Relatively recent work has reported that networks of neurons can produce avalanches of activity whose sizes follow a power law distribution. This suggests that these networks may be operating near a critical point, poised between a phase where activity rapidly dies out and a phase where activity is amplified over time. The hypothesis that the electrical activity of neural networks in the brain is critical is potentially important, as many simulations suggest that information processing functions would be optimized at the critical point. This hypothesis, however, is still controversial. Here we will explain the concept of criticality and review the substantial objections to the criticality hypothesis raised by skeptics. Points and counter points are presented in dialog form. PMID:22701101

  13. [Recommendations of the Infectious Diseases Work Group (GTEI) of the Spanish Society of Intensive and Critical Care Medicine and Coronary Units (SEMICYUC) and the Infections in Critically Ill Patients Study Group (GEIPC) of the Spanish Society of Infectious Diseases and Clinical Microbiology (SEIMC) for the diagnosis and treatment of influenza A/H1N1 in seriously ill adults admitted to the Intensive Care Unit].

    PubMed

    Rodríguez, A; Alvarez-Rocha, L; Sirvent, J M; Zaragoza, R; Nieto, M; Arenzana, A; Luque, P; Socías, L; Martín, M; Navarro, D; Camarena, J; Lorente, L; Trefler, S; Vidaur, L; Solé-Violán, J; Barcenilla, F; Pobo, A; Vallés, J; Ferri, C; Martín-Loeches, I; Díaz, E; López, D; López-Pueyo, M J; Gordo, F; del Nogal, F; Marqués, A; Tormo, S; Fuset, M P; Pérez, F; Bonastre, J; Suberviola, B; Navas, E; León, C

    2012-03-01

    The diagnosis of influenza A/H1N1 is mainly clinical, particularly during peak or seasonal flu outbreaks. A diagnostic test should be performed in all patients with fever and flu symptoms that require hospitalization. The respiratory sample (nasal or pharyngeal exudate or deeper sample in intubated patients) should be obtained as soon as possible, with the immediate start of empirical antiviral treatment. Molecular methods based on nucleic acid amplification techniques (RT-PCR) are the gold standard for the diagnosis of influenza A/H1N1. Immunochromatographic methods have low sensitivity; a negative result therefore does not rule out active infection. Classical culture is slow and has low sensitivity. Direct immunofluorescence offers a sensitivity of 90%, but requires a sample of high quality. Indirect methods for detecting antibodies are only of epidemiological interest. Patients with A/H1N1 flu may have relative leukopenia and elevated serum levels of LDH, CPK and CRP, but none of these variables are independently associated to the prognosis. However, plasma LDH> 1500 IU/L, and the presence of thrombocytopenia <150 x 10(9)/L, could define a patient population at risk of suffering serious complications. Antiviral administration (oseltamivir) should start early (<48 h from the onset of symptoms), with a dose of 75 mg every 12h, and with a duration of at least 7 days or until clinical improvement is observed. Early antiviral administration is associated to improved survival in critically ill patients. New antiviral drugs, especially those formulated for intravenous administration, may be the best choice in future epidemics. Patients with a high suspicion of influenza A/H1N1 infection must continue with antiviral treatment, regardless of the negative results of initial tests, unless an alternative diagnosis can be established or clinical criteria suggest a low probability of influenza. In patients with influenza A/H1N1 pneumonia, empirical antibiotic therapy should

  14. 75 FR 5146 - Hewlett Packard Company Business Critical Systems, Mission Critical Business Software Division...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-01

    ... Business Software Division, OpenVMS Operating System Development Group, Including Employees Working Off... Business Critical Systems, Mission Critical Business Software Division, OpenVMS Operating System..., OpenVMS Operating System Development Group, including employees working off site in New Hampshire...

  15. Critical Discourse Analysis and Critical Thinking: An Experimental Study in an EFL Context

    ERIC Educational Resources Information Center

    Hashemi, Mohammad Reza; Ghanizadeh, Afsaneh

    2012-01-01

    The present study investigated the impact of critical discourse analysis (CDA) on TEFL students' critical thinking (CT) ability in "Reading Journalistic Texts" classes. In so doing, the study utilized an experimental design with 24 participants in the control group and 29 participants in the experimental group. The results of a pretest indicated…

  16. Critical Discourse Analysis and Critical Thinking: An Experimental Study in an EFL Context

    ERIC Educational Resources Information Center

    Hashemi, Mohammad Reza; Ghanizadeh, Afsaneh

    2012-01-01

    The present study investigated the impact of critical discourse analysis (CDA) on TEFL students' critical thinking (CT) ability in "Reading Journalistic Texts" classes. In so doing, the study utilized an experimental design with 24 participants in the control group and 29 participants in the experimental group. The results of a pretest indicated…

  17. Leader as critical thinker.

    PubMed

    Lemire, Judith A

    2002-01-01

    A leader possess the critical-thinking knowledge and skills that provide the framework from which complex problem solving evolves. This article explores the leader as critical thinker, including a progressive plan for integrating critical-thinking concepts and associated teaching strategies into the RN to BSN and graduate curricula. To improve the critical thinking of nurses, educators must emphasize the cognitive and disposition aspects of critical thinking; promote active and sequential learning; role model critical thinking; design practical that focus on leadership and critical thinking; and conduct valid and consistent evaluations. The acquisition and application of critical thinking and problem-solving skills are progressive and refined through life-long learning and experience. This expertise begins with a sound knowledge base of the critical thinking composite and problem-solving strategies.

  18. Renormalization group for evolving networks.

    PubMed

    Dorogovtsev, S N

    2003-04-01

    We propose a renormalization group treatment of stochastically growing networks. As an example, we study percolation on growing scale-free networks in the framework of a real-space renormalization group approach. As a result, we find that the critical behavior of percolation on the growing networks differs from that in uncorrelated networks.

  19. Teaching critical thinking

    PubMed Central

    Holmes, N. G.; Wieman, Carl E.; Bonn, D. A.

    2015-01-01

    The ability to make decisions based on data, with its inherent uncertainties and variability, is a complex and vital skill in the modern world. The need for such quantitative critical thinking occurs in many different contexts, and although it is an important goal of education, that goal is seldom being achieved. We argue that the key element for developing this ability is repeated practice in making decisions based on data, with feedback on those decisions. We demonstrate a structure for providing suitable practice that can be applied in any instructional setting that involves the acquisition of data and relating that data to scientific models. This study reports the results of applying that structure in an introductory physics laboratory course. Students in an experimental condition were repeatedly instructed to make and act on quantitative comparisons between datasets, and between data and models, an approach that is common to all science disciplines. These instructions were slowly faded across the course. After the instructions had been removed, students in the experimental condition were 12 times more likely to spontaneously propose or make changes to improve their experimental methods than a control group, who performed traditional experimental activities. The students in the experimental condition were also four times more likely to identify and explain a limitation of a physical model using their data. Students in the experimental condition also showed much more sophisticated reasoning about their data. These differences between the groups were seen to persist into a subsequent course taken the following year. PMID:26283351

  20. Teaching critical thinking.

    PubMed

    Holmes, N G; Wieman, Carl E; Bonn, D A

    2015-09-08

    The ability to make decisions based on data, with its inherent uncertainties and variability, is a complex and vital skill in the modern world. The need for such quantitative critical thinking occurs in many different contexts, and although it is an important goal of education, that goal is seldom being achieved. We argue that the key element for developing this ability is repeated practice in making decisions based on data, with feedback on those decisions. We demonstrate a structure for providing suitable practice that can be applied in any instructional setting that involves the acquisition of data and relating that data to scientific models. This study reports the results of applying that structure in an introductory physics laboratory course. Students in an experimental condition were repeatedly instructed to make and act on quantitative comparisons between datasets, and between data and models, an approach that is common to all science disciplines. These instructions were slowly faded across the course. After the instructions had been removed, students in the experimental condition were 12 times more likely to spontaneously propose or make changes to improve their experimental methods than a control group, who performed traditional experimental activities. The students in the experimental condition were also four times more likely to identify and explain a limitation of a physical model using their data. Students in the experimental condition also showed much more sophisticated reasoning about their data. These differences between the groups were seen to persist into a subsequent course taken the following year.

  1. Group Learning.

    ERIC Educational Resources Information Center

    Black, Susan

    1992-01-01

    Research suggests that cooperative learning works best when students are first taught group-processing skills, such as leadership, decision making, communication, trust building, and conflict management. Inadequate teacher training and boring assignments can torpedo cooperative learning efforts. Administrators should reassure teachers with…

  2. Critical sound propagation in mixtures

    NASA Astrophysics Data System (ADS)

    Folk, R.; Moser, G.

    1998-01-01

    We calculate critical effects in the sound propagation in mixtures near consolute or plait points within a non-asymptotic renormalization group theory and derive general expressions for the frequency-dependent sound velocity and sound attenuation. The critical non-asymptotic time scale in the sound mode in mixtures is set by an effective order parameter Onsager coefficient containing a dynamical parameter related to the enhancement of the thermal conductivity in the mixture, not considered so far. The differences in the critical behavior near the consolute and plait point are due to the different non-asymptotic behavior of the zero-frequency sound velocity. We compare our predictions for the sound velocity and sound absorption near the plait point in 3He-4He mixtures.

  3. Critical areas: Satellite power systems concepts

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Critical Areas are defined and discussed in the various areas pertinent to satellite power systems. The presentation is grouped into five areas (General, Space Systems, Solar Energy Conversion, Microwave Systems, and Environment/Ecology) with a sixth area (Power Relay) considered separately in an appendix. Areas for Future Consideration as critical areas are discussed in a second appendix.

  4. Supporting Critical Dialogue across Educational Contexts

    ERIC Educational Resources Information Center

    Laman, Tasha Tropp; Jewett, Pamela; Jennings, Louise B.; Wilson, Jennifer L.; Souto-Manning, Mariana

    2012-01-01

    This article draws upon five different empirical studies to examine how critical dialogue can be fostered across educational settings and with diverse populations: middle-school students discussing immigration picture books, a teacher study group exploring texts on homelessness, a teacher education class studying critical literacy, working class…

  5. Anomalous critical fields in quantum critical superconductors

    PubMed Central

    Putzke, C.; Walmsley, P.; Fletcher, J. D.; Malone, L.; Vignolles, D.; Proust, C.; Badoux, S.; See, P.; Beere, H. E.; Ritchie, D. A.; Kasahara, S.; Mizukami, Y.; Shibauchi, T.; Matsuda, Y.; Carrington, A.

    2014-01-01

    Fluctuations around an antiferromagnetic quantum critical point (QCP) are believed to lead to unconventional superconductivity and in some cases to high-temperature superconductivity. However, the exact mechanism by which this occurs remains poorly understood. The iron-pnictide superconductor BaFe2(As1−xPx)2 is perhaps the clearest example to date of a high-temperature quantum critical superconductor, and so it is a particularly suitable system to study how the quantum critical fluctuations affect the superconducting state. Here we show that the proximity of the QCP yields unexpected anomalies in the superconducting critical fields. We find that both the lower and upper critical fields do not follow the behaviour, predicted by conventional theory, resulting from the observed mass enhancement near the QCP. Our results imply that the energy of superconducting vortices is enhanced, possibly due to a microscopic mixing of antiferromagnetism and superconductivity, suggesting that a highly unusual vortex state is realized in quantum critical superconductors. PMID:25477044

  6. Building the Emotional Intelligence of Groups.

    ERIC Educational Resources Information Center

    Druskat, Vanessa Urch; Wolff, Steven B.

    2001-01-01

    Research has found that individual emotional intelligence has a group analog and it is critical to groups' effectiveness. Teams can develop greater emotional intelligence and boost their overall performance. (JOW)

  7. Building the Emotional Intelligence of Groups.

    ERIC Educational Resources Information Center

    Druskat, Vanessa Urch; Wolff, Steven B.

    2001-01-01

    Research has found that individual emotional intelligence has a group analog and it is critical to groups' effectiveness. Teams can develop greater emotional intelligence and boost their overall performance. (JOW)

  8. Toward critical bioethics.

    PubMed

    Árnason, Vilhjálmur

    2015-04-01

    This article deals with the question as to what makes bioethics a critical discipline. It considers different senses of criticism and evaluates their strengths and weaknesses. A primary method in bioethics as a philosophical discipline is critical thinking, which implies critical evaluation of concepts, positions, and arguments. It is argued that the type of analytical criticism that restricts its critical role to critical thinking of this type often suffers from other intellectual flaws. Three examples are taken to demonstrate this: premature criticism, uncritical self-understanding of theoretical assumptions, and narrow framing of bioethical issues. Such flaws can lead both to unfair treatment of authors and to uncritical discussion of topics. In this context, the article makes use of Häyry's analysis of different rationalities in bioethical approaches and argues for the need to recognize the importance of communicative rationality for critical bioethics. A radically different critical approach in bioethics, rooted in social theory, focuses on analyses of power relations neglected in mainstream critical thinking. It is argued that, although this kind of criticism provides an important alternative in bioethics, it suffers from other shortcomings that are rooted in a lack of normative dimensions. In order to complement these approaches and counter their shortcomings, there is a need for a bioethics enlightened by critical hermeneutics. Such hermeneutic bioethics is aware of its own assumptions, places the issues in a wide context, and reflects critically on the power relations that stand in the way of understanding them. Moreover, such an approach is dialogical, which provides both a critical exercise of speech and a normative dimension implied in the free exchange of reasons and arguments. This discussion is framed by Hedgecoe's argument that critical bioethics needs four elements: to be empirically rooted, theory challenging, reflexive, and politely skeptical.

  9. Cantor Groups

    ERIC Educational Resources Information Center

    Mathes, Ben; Dow, Chris; Livshits, Leo

    2011-01-01

    The Cantor subset of the unit interval [0, 1) is "large" in cardinality and also "large" algebraically, that is, the smallest subgroup of [0, 1) generated by the Cantor set (using addition mod 1 as the group operation) is the whole of [0, 1). In this paper, we show how to construct Cantor-like sets which are "large" in cardinality but "small"…

  10. Local Group

    NASA Astrophysics Data System (ADS)

    Mateo, M.; Murdin, P.

    2000-11-01

    Not long after EDWIN HUBBLE established that galaxies are `island universes' similar to our home galaxy, the MILKY WAY, he realized that a few of these external galaxies are considerably closer to us than any others. In 1936 he first coined the term `Local Group' in his famous book The Realm of the Nebulae to identify our nearest galactic neighbors. More than 60 yr later, the galaxies of the Loca...

  11. Underrepresented groups

    NASA Technical Reports Server (NTRS)

    Peters, David A.

    1990-01-01

    The problem with the shortage of under represented groups in science and engineering is absolutely crucial, especially considering that U.S. will experience a shortage of 560,000 science and engineering personnel by the year 2010. Most studies by the National Science Foundation also concluded that projected shortages cannot be alleviated without significant increases in the involvement of Blacks, Hispanics, Native Americans, handicapped persons, and women.

  12. Reimagining Critical Theory

    ERIC Educational Resources Information Center

    Rexhepi, Jevdet; Torres, Carlos Alberto

    2011-01-01

    This paper discusses Critical Theory, a model of theorizing in the field of the political sociology of education. We argue for a "reimagined" Critical Theory to herald an empowering, liberatory education that fosters curiosity and critical thinking, and a means for successful bottom-up, top-down political engagement. We present arguments…

  13. Creating a Critical Thinker

    ERIC Educational Resources Information Center

    Piergiovanni, Polly R.

    2014-01-01

    A college education is expected to improve students' critical thinking skills. Keeping students active in class--through writing activities and class discussion--has been shown to help students think critically. In this article, creative hands-on activities, which are common in engineering courses, are shown to improve students' critical thinking…

  14. Foundations for Critical Thinking

    ERIC Educational Resources Information Center

    Bers, Trudy; Chun, Marc; Daly, William T.; Harrington, Christine; Tobolowsky, Barbara F.

    2015-01-01

    "Foundations for Critical Thinking" explores the landscape of critical-thinking skill development and pedagogy through foundational chapters and institutional case studies involving a range of students in diverse settings. By establishing a link between active learning and improved critical thinking, this resource encourages all higher…

  15. Critical values in hematology.

    PubMed

    McFarlane, A; Aslan, B; Raby, A; Bourner, G; Padmore, R

    2015-02-01

    Critical values are life-threatening results that require immediate notification to the patient's healthcare provider. Accreditation bodies require laboratories to establish critical values. A survey of Ontario laboratories was conducted to determine current practice for critical values in hematology. The survey was sent to 182 participants questioning sources for establishing critical values, levels, review frequency, delta checks, and reporting. The survey was completed by laboratory managers, supervisors, technical specialists, senior technologists, and bench technologists working in hematology. The majority of participating laboratories have established critical values limits for hemoglobin, leukocyte counts, and platelet counts. Most laboratories also include the presence of malaria parasites and blast cells. Some laboratories reported the presence of plasma cells, sickle cells, schistocytes, and spherocytes as critical values. Multiple sources are used for establishing a critical value policy. There was variability for the frequency of critical values review. Rules may differ for a first-time patient sample vs. a repeat patient sample. Delta checks are seldom used to determine whether a result should be called a critical value. Most participants require the individual taking the critical result(s) to read back and confirm that they are directly involved with the patient's care. There is a lack of consensus for critical values reporting in hematology. As critical value reporting is crucial for patient safety, standardization of this practice would be beneficial. © 2014 John Wiley & Sons Ltd.

  16. Reconceptualising Critical Digital Literacy

    ERIC Educational Resources Information Center

    Pangrazio, Luciana

    2016-01-01

    While it has proved a useful concept during the past 20 years, the notion of "critical digital literacy" requires rethinking in light of the fast-changing nature of young people's digital practices. This paper contrasts long-established notions of "critical digital literacy" (based primarily around the critical consumption of…

  17. Reconceptualising Critical Digital Literacy

    ERIC Educational Resources Information Center

    Pangrazio, Luciana

    2016-01-01

    While it has proved a useful concept during the past 20 years, the notion of "critical digital literacy" requires rethinking in light of the fast-changing nature of young people's digital practices. This paper contrasts long-established notions of "critical digital literacy" (based primarily around the critical consumption of…

  18. Poetry: Sources for Criticism.

    ERIC Educational Resources Information Center

    Van Noate, Judith, Comp.

    This handout is a guide to library resources in the J. Murrey Atkins Library at the University of North Carolina-Charlotte for the criticism of poetry. The guide enables the reader to find sources of criticism on poetry, including critical articles and essays about single poems, or writings on the work of a single author. The guide's sections…

  19. Teaching Critical Reflection

    ERIC Educational Resources Information Center

    Smith, Elizabeth

    2011-01-01

    Despite long-standing commitment to the notion of critical reflection across the healthcare professions it is unusual for critical theory and practice to be taught as explicit subjects in healthcare higher education. There is evidence to show that reflective techniques such as critical portfolios and reflective diaries can help students to…

  20. Creating a Critical Thinker

    ERIC Educational Resources Information Center

    Piergiovanni, Polly R.

    2014-01-01

    A college education is expected to improve students' critical thinking skills. Keeping students active in class--through writing activities and class discussion--has been shown to help students think critically. In this article, creative hands-on activities, which are common in engineering courses, are shown to improve students' critical thinking…

  1. Teaching Critical Reflection

    ERIC Educational Resources Information Center

    Smith, Elizabeth

    2011-01-01

    Despite long-standing commitment to the notion of critical reflection across the healthcare professions it is unusual for critical theory and practice to be taught as explicit subjects in healthcare higher education. There is evidence to show that reflective techniques such as critical portfolios and reflective diaries can help students to…

  2. Foundations for Critical Thinking

    ERIC Educational Resources Information Center

    Bers, Trudy; Chun, Marc; Daly, William T.; Harrington, Christine; Tobolowsky, Barbara F.

    2015-01-01

    "Foundations for Critical Thinking" explores the landscape of critical-thinking skill development and pedagogy through foundational chapters and institutional case studies involving a range of students in diverse settings. By establishing a link between active learning and improved critical thinking, this resource encourages all higher…

  3. Criticism, Visible and Invisible.

    ERIC Educational Resources Information Center

    Frye, Northrop

    1964-01-01

    The central activity of literary criticism, the understanding of literature, is related to the process of establishing a context for the works of literature being studied. Choosing not to discuss the factual elements of literary criticism, the author clarifies and concentrates on the "lower" and "upper" limits of criticism. While the "lower" limit…

  4. Reimagining Critical Theory

    ERIC Educational Resources Information Center

    Rexhepi, Jevdet; Torres, Carlos Alberto

    2011-01-01

    This paper discusses Critical Theory, a model of theorizing in the field of the political sociology of education. We argue for a "reimagined" Critical Theory to herald an empowering, liberatory education that fosters curiosity and critical thinking, and a means for successful bottom-up, top-down political engagement. We present arguments…

  5. Critical effect of dependency groups on the function of networks.

    PubMed

    Parshani, Roni; Buldyrev, Sergey V; Havlin, Shlomo

    2011-01-18

    Current network models assume one type of links to define the relations between the network entities. However, many real networks can only be correctly described using two different types of relations. Connectivity links that enable the nodes to function cooperatively as a network and dependency links that bind the failure of one network element to the failure of other network elements. Here we present an analytical framework for studying the robustness of networks that include both connectivity and dependency links. We show that a synergy exists between the failure of connectivity and dependency links that leads to an iterative process of cascading failures that has a devastating effect on the network stability. We present exact analytical results for the dramatic change in the network behavior when introducing dependency links. For a high density of dependency links, the network disintegrates in a form of a first-order phase transition, whereas for a low density of dependency links, the network disintegrates in a second-order transition. Moreover, opposed to networks containing only connectivity links where a broader degree distribution results in a more robust network, when both types of links are present a broad degree distribution leads to higher vulnerability.

  6. Critical Literacy in a Primary Multiliteracies Classroom: The Hurricane Group

    ERIC Educational Resources Information Center

    Silvers, Penny; Shorey, Mary; Crafton, Linda

    2010-01-01

    This qualitative research presents an expanded perspective of literacy practices in which young students engage in multiple literacies while exploring personal inquiries about Hurricane Katrina in New Orleans, LA. An extended classroom example and analysis taken from a broader research project focusing on early multiliteracies, illustrates the…

  7. Critical effect of dependency groups on the function of networks

    PubMed Central

    Parshani, Roni; Buldyrev, Sergey V.; Havlin, Shlomo

    2011-01-01

    Current network models assume one type of links to define the relations between the network entities. However, many real networks can only be correctly described using two different types of relations. Connectivity links that enable the nodes to function cooperatively as a network and dependency links that bind the failure of one network element to the failure of other network elements. Here we present an analytical framework for studying the robustness of networks that include both connectivity and dependency links. We show that a synergy exists between the failure of connectivity and dependency links that leads to an iterative process of cascading failures that has a devastating effect on the network stability. We present exact analytical results for the dramatic change in the network behavior when introducing dependency links. For a high density of dependency links, the network disintegrates in a form of a first-order phase transition, whereas for a low density of dependency links, the network disintegrates in a second-order transition. Moreover, opposed to networks containing only connectivity links where a broader degree distribution results in a more robust network, when both types of links are present a broad degree distribution leads to higher vulnerability. PMID:21191103

  8. Critical Literacy in a Primary Multiliteracies Classroom: The Hurricane Group

    ERIC Educational Resources Information Center

    Silvers, Penny; Shorey, Mary; Crafton, Linda

    2010-01-01

    This qualitative research presents an expanded perspective of literacy practices in which young students engage in multiple literacies while exploring personal inquiries about Hurricane Katrina in New Orleans, LA. An extended classroom example and analysis taken from a broader research project focusing on early multiliteracies, illustrates the…

  9. Illinois Wind Workers Group

    SciTech Connect

    David G. Loomis

    2012-05-28

    The Illinois Wind Working Group (IWWG) was founded in 2006 with about 15 members. It has grown to over 200 members today representing all aspects of the wind industry across the State of Illinois. In 2008, the IWWG developed a strategic plan to give direction to the group and its activities. The strategic plan identifies ways to address critical market barriers to the further penetration of wind. The key to addressing these market barriers is public education and outreach. Since Illinois has a restructured electricity market, utilities no longer have a strong control over the addition of new capacity within the state. Instead, market acceptance depends on willing landowners to lease land and willing county officials to site wind farms. Many times these groups are uninformed about the benefits of wind energy and unfamiliar with the process. Therefore, many of the project objectives focus on conferences, forum, databases and research that will allow these stakeholders to make well-educated decisions.

  10. Group Connections: Whole Group Teaching.

    ERIC Educational Resources Information Center

    Griffiths, Dorothy

    2002-01-01

    A learner-centered approach to adult group instruction involved learners in investigating 20th-century events. The approach allowed learners to concentrate on different activities according to their abilities and gave them opportunities to develop basic skills and practice teamwork. (SK)

  11. Criticality in epidemiology

    NASA Astrophysics Data System (ADS)

    Stollenwerk, Nico; Jansen, Vincent A. A.

    For a long time criticality has been considered in epidemiological models. We review the body of theory developed over the last twenty five years for the simplest models. It is at first glance difficult to imagine that an epidemiological system operates at a very fine tuned critical state as opposed to any other parameter region. However, the advent of self-organized criticality has given hints in how to interpret large fluctuations observed in many natural systems including epidemiological systems. We show some scenarios where criticality has been observed (e.g., measles under vaccination) and where evolution towards a critical state can explain fluctuations (e.g., meningococcal disease.)

  12. Facilitating a Summer Reading Book Group Program

    ERIC Educational Resources Information Center

    Malin, Ginger Goldman

    2007-01-01

    Summer book groups enhance and sustain student literacy behaviors over the break, making available an enjoyable social forum for critical-thinking and critical-reading practices to occur naturally. Significantly, the book groups grant faculty and students an informal space to connect meaningfully through reflective discussion of texts. Because…

  13. Facilitating a Summer Reading Book Group Program

    ERIC Educational Resources Information Center

    Malin, Ginger Goldman

    2007-01-01

    Summer book groups enhance and sustain student literacy behaviors over the break, making available an enjoyable social forum for critical-thinking and critical-reading practices to occur naturally. Significantly, the book groups grant faculty and students an informal space to connect meaningfully through reflective discussion of texts. Because…

  14. Quality of decision making and group norms.

    PubMed

    Postmes, T; Spears, R; Cihangir, S

    2001-06-01

    Two studies investigated the impact of group norms for maintaining consensus versus norms for critical thought on group decisions in a modification of the biased sampling paradigm (G. Stasser & W. Titus, 1985). Both studies showed that critical norms improved the quality of decisions, whereas consensus norms did not. This effect appeared to be mediated by the perceived value of shared and unshared information: Consensus norm groups valued shared information more highly than critical groups did, and valence was a good predictor of decision outcome. In addition, the 2nd study showed that the group norm manipulation has no impact on individual decisions, consistent with the assumption that this is a group effect. Results suggest that the content of group norms is an important factor influencing the quality of group decision-making processes and that the content of group norms may be related to the group's proneness for groupthink.

  15. Critical neuroscience meets medical humanities.

    PubMed

    Slaby, Jan

    2015-06-01

    This programmatic theory paper sketches a conceptual framework that might inspire work in critical Medical Humanities. For this purpose, Kaushik Sunder Rajan's account of biocapital is revisited and discussed in relation to the perspective of a critical neuroscience. Critical neuroscience is an encompassing positioning towards the recent public prominence of the brain and brain-related practices, tools and discourses. The proposed analytical scheme has five focal nodes: capital, life, technoscience, (neoliberal) politics and subjectivity. A special emphasis will be placed on contemporary framings of subjectivity, as it is here where deep-reaching entanglements of personhood with scientific practice and discourse, medical and informational technologies, and economic formations are most evident. Notably, the emerging subject position of the 'prospective health consumer' will be discussed as it figures prominently in the terrain between neuroscience and other medico-scientific disciplines. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  16. Cardiovascular group

    NASA Technical Reports Server (NTRS)

    Blomqvist, Gunnar

    1989-01-01

    As a starting point, the group defined a primary goal of maintaining in flight a level of systemic oxygen transport capacity comparable to each individual's preflight upright baseline. The goal of maintaining capacity at preflight levels would seem to be a reasonable objective for several different reasons, including the maintenance of good health in general and the preservation of sufficient cardiovascular reserve capacity to meet operational demands. It is also important not to introduce confounding variables in whatever other physiological studies are being performed. A change in the level of fitness is likely to be a significant confounding variable in the study of many organ systems. The principal component of the in-flight cardiovascular exercise program should be large-muscle activity such as treadmill exercise. It is desirable that at least one session per week be monitored to assure maintenance of proper functional levels and to provide guidance for any adjustments of the exercise prescription. Appropriate measurements include evaluation of the heart-rate/workload or the heart-rate/oxygen-uptake relationship. Respiratory gas analysis is helpful by providing better opportunities to document relative workload levels from analysis of the interrelationships among VO2, VCO2, and ventilation. The committee felt that there is no clear evidence that any particular in-flight exercise regimen is protective against orthostatic hypotension during the early readaptation phase. Some group members suggested that maintenance of the lower body muscle mass and muscle tone may be helpful. There is also evidence that late in-flight interventions to reexpand blood volume to preflight levels are helpful in preventing or minimizing postflight orthostatic hypotension.

  17. Critical fluid light scattering

    NASA Technical Reports Server (NTRS)

    Gammon, Robert W.

    1988-01-01

    The objective is to measure the decay rates of critical density fluctuations in a simple fluid (xenon) very near its liquid-vapor critical point using laser light scattering and photon correlation spectroscopy. Such experiments were severely limited on Earth by the presence of gravity which causes large density gradients in the sample when the compressibility diverges approaching the critical point. The goal is to measure fluctuation decay rates at least two decades closer to the critical point than is possible on earth, with a resolution of 3 microK. This will require loading the sample to 0.1 percent of the critical density and taking data as close as 100 microK to the critical temperature. The minimum mission time of 100 hours will allow a complete range of temperature points to be covered, limited by the thermal response of the sample. Other technical problems have to be addressed such as multiple scattering and the effect of wetting layers. The experiment entails measurement of the scattering intensity fluctuation decay rate at two angles for each temperature and simultaneously recording the scattering intensities and sample turbidity (from the transmission). The analyzed intensity and turbidity data gives the correlation length at each temperature and locates the critical temperature. The fluctuation decay rate data from these measurements will provide a severe test of the generalized hydrodynamic theories of transport coefficients in the critical regions. When compared to equivalent data from binary liquid critical mixtures they will test the universality of critical dynamics.

  18. Critical Psychologies for Critical Health Literacies

    ERIC Educational Resources Information Center

    Corcoran, Tim

    2014-01-01

    Health education is largely informed by psychological theories and practices that pursue reductionist views of people learning. However, critical attention is moving to understand health in ways that reconsider relationships to context and the forms of life within which everyday living takes place. This shift is apparent in theoretical…

  19. Critical Psychologies for Critical Health Literacies

    ERIC Educational Resources Information Center

    Corcoran, Tim

    2014-01-01

    Health education is largely informed by psychological theories and practices that pursue reductionist views of people learning. However, critical attention is moving to understand health in ways that reconsider relationships to context and the forms of life within which everyday living takes place. This shift is apparent in theoretical…

  20. Criticality Model Report

    SciTech Connect

    J.M. Scaglione

    2003-03-12

    The purpose of the ''Criticality Model Report'' is to validate the MCNP (CRWMS M&O 1998h) code's ability to accurately predict the effective neutron multiplication factor (k{sub eff}) for a range of conditions spanned by various critical configurations representative of the potential configurations commercial reactor assemblies stored in a waste package may take. Results of this work are an indication of the accuracy of MCNP for calculating eigenvalues, which will be used as input for criticality analyses for spent nuclear fuel (SNF) storage at the proposed Monitored Geologic Repository. The scope of this report is to document the development and validation of the criticality model. The scope of the criticality model is only applicable to commercial pressurized water reactor fuel. Valid ranges are established as part of the validation of the criticality model. This model activity follows the description in BSC (2002a).

  1. Critical incident reporting systems.

    PubMed

    Ahluwalia, Jag; Marriott, Lin

    2005-02-01

    Approximately 10% of all hospital admissions are complicated by critical incidents in which harm is caused to the patient - this amounts to more than 850,000 incidents annually. Critical incident reporting (CIR) systems refer to the structured reporting, collation and analysis of such incidents. This article describes the attributes required for an effective CIR system. Example neonatal trigger events and a management pathway for handling a critical incident report are described. The benefits and limitations of CIR systems, reactive and prospective approaches to the analysis of actual or potential critical incidents and the assessment of risk are also reviewed. Individual human error is but one contributor in the majority of critical incidents. Recognition of this and the fostering of an organisational culture that views critical incident reports as an opportunity to learn and to improve future patient care is vital if CIR systems are to be effective.

  2. Group evaporation

    NASA Technical Reports Server (NTRS)

    Shen, Hayley H.

    1991-01-01

    Liquid fuel combustion process is greatly affected by the rate of droplet evaporation. The heat and mass exchanges between gas and liquid couple the dynamics of both phases in all aspects: mass, momentum, and energy. Correct prediction of the evaporation rate is therefore a key issue in engineering design of liquid combustion devices. Current analytical tools for characterizing the behavior of these devices are based on results from a single isolated droplet. Numerous experimental studies have challenged the applicability of these results in a dense spray. To account for the droplets' interaction in a dense spray, a number of theories have been developed in the past decade. Herein, two tasks are examined. One was to study how to implement the existing theoretical results, and the other was to explore the possibility of experimental verifications. The current theoretical results of group evaporation are given for a monodispersed cluster subject to adiabatic conditions. The time evolution of the fluid mechanic and thermodynamic behavior in this cluster is derived. The results given are not in the form of a subscale model for CFD codes.

  3. Vulnerability of critical infrastructures : identifying critical nodes.

    SciTech Connect

    Cox, Roger Gary; Robinson, David Gerald

    2004-06-01

    The objective of this research was the development of tools and techniques for the identification of critical nodes within critical infrastructures. These are nodes that, if disrupted through natural events or terrorist action, would cause the most widespread, immediate damage. This research focuses on one particular element of the national infrastructure: the bulk power system. Through the identification of critical elements and the quantification of the consequences of their failure, site-specific vulnerability analyses can be focused at those locations where additional security measures could be effectively implemented. In particular, with appropriate sizing and placement within the grid, distributed generation in the form of regional power parks may reduce or even prevent the impact of widespread network power outages. Even without additional security measures, increased awareness of sensitive power grid locations can provide a basis for more effective national, state and local emergency planning. A number of methods for identifying critical nodes were investigated: small-world (or network theory), polyhedral dynamics, and an artificial intelligence-based search method - particle swarm optimization. PSO was found to be the only viable approach and was applied to a variety of industry accepted test networks to validate the ability of the approach to identify sets of critical nodes. The approach was coded in a software package called Buzzard and integrated with a traditional power flow code. A number of industry accepted test networks were employed to validate the approach. The techniques (and software) are not unique to power grid network, but could be applied to a variety of complex, interacting infrastructures.

  4. Critical Viscosity of Xenon

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The Critical Viscosity of Xenon Experiment (CVX-2) on the STS-107 Research 1 mission in 2002 will measure the viscous behavior of xenon, a heavy inert gas used in flash lamps and ion rocket engines, at its critical point. Because xenon near the critical point will collapse under its own weight, experiments on Earth (green line) are limited as they get closer (toward the left) to the critical point. CVX in the microgravity of space (red line) moved into unmeasured territory that scientists had not been able to reach.

  5. Critical Viscosity of Xenon

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The Critical Viscosity of Xenon Experiment (CVX-2) on the STS-107 Research 1 mission in 2002 will measure the viscous behavior of xenon, a heavy inert gas used in flash lamps and ion rocket engines, at its critical point. Because xenon near the critical point will collapse under its own weight, experiments on Earth (green line) are limited as they get closer (toward the left) to the critical point. CVX in the microgravity of space (red line) moved into unmeasured territory that scientists had not been able to reach.

  6. Against Critical Thinking Pedagogy

    ERIC Educational Resources Information Center

    Hayes, David

    2015-01-01

    Critical thinking pedagogy is misguided. Ostensibly a cure for narrowness of thought, by using the emotions appropriate to conflict, it names only one mode of relation to material among many others. Ostensibly a cure for fallacies, critical thinking tends to dishonesty in practice because it habitually leaps to premature ideas of what the object…

  7. Rethinking Critical Thinking

    ERIC Educational Resources Information Center

    Downs, Christopher J.

    2008-01-01

    Critical thinking is of primary importance in higher education, yet the concept remains slippery and the skill elusive. The author argues that most current critical thinking textbooks are out of line with the seminal work of John Dewey. Rather than logical argument and justification, it is suggested that carefulness, open-mindedness and creativity…

  8. Achieving comprehensive critical care.

    PubMed

    Derham, Catherine

    2007-01-01

    The policy document, Comprehensive Critical Care, suggested that patients with critical care needs should expect the same standard of care wherever they are nursed, be that in a traditional critical care setting or in a general ward area. It is recognized that in order for this to occur, the developmental needs of ward nurses need to be met to enable them to care for patients with level 1 and level 2 needs. A second document, The Nursing Contribution to the Provision of Comprehensive Critical Care for Adults: A strategic Programme of Action, proposed a programme of action and outlined five priority areas to be considered to ensure the success of comprehensive critical care. Education, training and workforce development was one of the areas outlined, and thus, in response, the role of the practice development facilitator was created as a means of developing the critical care knowledge, skills and practice in ward areas. It became apparent that education and training alone were insufficient to ensure that the aims of comprehensive critical care were realized. The way in which the nurses approached and organized their work and the availability of resources had a great impact on the ability of staff to care for these patients. It is argued that achieving comprehensive critical care is complex and that a multi-dimensional approach to the implementation of policy is essential in order to realize its aims.

  9. Critical Chain Exercises

    ERIC Educational Resources Information Center

    Doyle, John Kevin

    2010-01-01

    Critical Chains project management focuses on holding buffers at the project level vs. task level, and managing buffers as a project resource. A number of studies have shown that Critical Chain project management can significantly improve organizational schedule fidelity (i.e., improve the proportion of projects delivered on time) and reduce…

  10. Critical Literacy: Foundational Notes

    ERIC Educational Resources Information Center

    Luke, Allan

    2012-01-01

    The term "critical literacy" refers to use of the technologies of print and other media of communication to analyze, critique, and transform the norms, rule systems, and practices governing the social fields of everyday life (A. Luke, 2004). Since Freire's (1970) educational projects in Brazil, approaches to critical literacy have been…

  11. Critical Pedagogy and Faith

    ERIC Educational Resources Information Center

    Neumann, Jacob W.

    2011-01-01

    Critical pedagogy has often been linked in the literature to faith traditions such as liberation theology, usually with the intent of improving or redirecting it. While recognizing and drawing from those previous linkages, Jacob Neumann goes further in this essay and develops the thesis that critical pedagogy can not just benefit from a connection…

  12. Criticism and the Curriculum.

    ERIC Educational Resources Information Center

    Smith, Paul; Foulke, Robert D.

    1964-01-01

    A revised English curriculum, based upon different kinds of literary criticism, is counseled in this two-part paper. Part 1 identifies four kinds of criticism--formalist, synoptic, extrinsic, and stylistic. A conventional English Curriculum is briefly outlined. Curricular theories are discussed and positive and negative attempts to define…

  13. Whiteness and Critical Pedagogy

    ERIC Educational Resources Information Center

    Allen, Ricky Lee

    2004-01-01

    The purpose of this article is to rethink critical pedagogy by imagining it from a race-radical perspective that owes its lineage to scholars like W. E. B. Du Bois. The author assembles a critical pedagogy that hopes to contribute to both the transformation of white identity and the abolition of white supremacy. He draws from the roots of critical…

  14. Robust Critical Point Detection

    SciTech Connect

    Bhatia, Harsh

    2016-07-28

    Robust Critical Point Detection is a software to compute critical points in a 2D or 3D vector field robustly. The software was developed as a part of the author's work at the lab as a Phd student under Livermore Scholar Program (now called Livermore Graduate Scholar Program).

  15. CRITICAL LOADS METHODS

    EPA Science Inventory

    I summarize the results of an interagency project that 1) defines a generic approach to quantifying and reporting critical loads, and 2) exercises that generic approach by examining a data rich system -- the critical loads of sulfur deposition and it's effect on the chronic acidi...

  16. Against Critical Thinking Pedagogy

    ERIC Educational Resources Information Center

    Hayes, David

    2015-01-01

    Critical thinking pedagogy is misguided. Ostensibly a cure for narrowness of thought, by using the emotions appropriate to conflict, it names only one mode of relation to material among many others. Ostensibly a cure for fallacies, critical thinking tends to dishonesty in practice because it habitually leaps to premature ideas of what the object…

  17. Rethinking Critical Thinking

    ERIC Educational Resources Information Center

    Downs, Christopher J.

    2008-01-01

    Critical thinking is of primary importance in higher education, yet the concept remains slippery and the skill elusive. The author argues that most current critical thinking textbooks are out of line with the seminal work of John Dewey. Rather than logical argument and justification, it is suggested that carefulness, open-mindedness and creativity…

  18. The Need for Critics.

    ERIC Educational Resources Information Center

    Purves, Alan C.

    1994-01-01

    Responds to an article in the same issue of this journal about educational criticism as a form of qualitative inquiry. Argues that research in education has become a dead end. Agrees in the main with the article, but finds its view of criticism somewhat limited. Discusses the classroom itself as hypertext. (SR)

  19. Encouragement for Thinking Critically

    ERIC Educational Resources Information Center

    Olivares, Sonia; Saiz, Carlos; Rivas, Silvia F.

    2013-01-01

    Introduction: Here we report the results obtained in an innovative teaching experience that encourages the development of Critical Thinking skills through motivational intervention. Understanding Critical Thinking as a theory of action, "we think to solve problems", and accompanying this concept with a program aimed at teaching/learning…

  20. Reflections on Critical Incidents.

    ERIC Educational Resources Information Center

    Thiel, Teresa

    1999-01-01

    Focuses on the reporting of critical incidents as a tool for self-reflection in a program to train English-as-a-Second-language (ESL) secondary school teachers in Malaysia. Case studies of critical incidents highlight the potential value of encouraging ESL trainee teachers to record, analyze, and reflect on significant personal events in their…

  1. Critical Literacy: Foundational Notes

    ERIC Educational Resources Information Center

    Luke, Allan

    2012-01-01

    The term "critical literacy" refers to use of the technologies of print and other media of communication to analyze, critique, and transform the norms, rule systems, and practices governing the social fields of everyday life (A. Luke, 2004). Since Freire's (1970) educational projects in Brazil, approaches to critical literacy have been…

  2. Critical Pedagogy and Faith

    ERIC Educational Resources Information Center

    Neumann, Jacob W.

    2011-01-01

    Critical pedagogy has often been linked in the literature to faith traditions such as liberation theology, usually with the intent of improving or redirecting it. While recognizing and drawing from those previous linkages, Jacob Neumann goes further in this essay and develops the thesis that critical pedagogy can not just benefit from a connection…

  3. Telemedicine in Critical Care

    PubMed Central

    Murias, Gastón; Sales, Bernat; Garcia-Esquirol, Oscar; Blanch, Lluis

    2009-01-01

    Critical care medicine is the specialty that cares for patients with acute life-threatening illnesses where intensivists look after all aspects of patient care. Nevertheless, shortage of physicians and nurses, the relationship between high costs and economic restrictions, and the fact that critical care knowledge is only available at big hospitals puts the system on the edge. In this scenario, telemedicine might provide solutions to improve availability of critical care knowledge where the patient is located, improve relationship between attendants in different institutions and education material for future specialist training. Current information technologies and networking capabilities should be exploited to improve intensivist coverage, advanced alarm systems and to have large critical care databases of critical care signals. PMID:19452034

  4. Specific heat critical amplitudes and the approach to bulk criticality in parallel plate geometries

    NASA Astrophysics Data System (ADS)

    Leite, M. M.; Nemirovsky, A. M.; Coutinho-Filho, M. D.

    1992-02-01

    We calculate the universal ration A+/ A- of the specific heat critical amplitudes of an Ising system confined in a layered geometry of thickness L in the regime L/ξ≥1, where ξ is the bulk critical correlation length. Using field-theoretic renormalization-group techniques we determine A+/ A- under various surface boundary conditions for the local field.

  5. Researching Critical Literacy: A Critical Study of Analysis of Classroom Discourse

    ERIC Educational Resources Information Center

    Van Sluys, Katie; Lewison, Mitzi; Flint, Amy Seely

    2006-01-01

    Studying critical literacies includes examining how research practices influence what is learned about classroom activity and the world. This article highlights the processes and practices used in studying 1 classroom conversation. The data, drawn from an elementary school classroom of a Critical Literacy in Action teacher-researcher group member,…

  6. Multimeson Yukawa interactions at criticality

    NASA Astrophysics Data System (ADS)

    Vacca, Gian Paolo; Zambelli, Luca

    2015-06-01

    The critical behavior of a relativistic Z2 -symmetric Yukawa model at zero temperature and density is discussed for a continuous number of fermion degrees of freedom and of spacetime dimensions, with emphasis on the role played by multimeson exchange in the Yukawa sector. We argue that this should be generically taken into account in studies based on the functional renormalization group, either in four-dimensional high-energy models or in lower-dimensional condensed-matter systems. By means of the latter method, we describe the generation of multicritical models in less than three dimensions, both at infinite and finite numbers of flavors. We also provide different estimates of the critical exponents of the chiral Ising universality class in three dimensions for various field contents, from a couple of massless Dirac fermions down to the supersymmetric theory with a single Majorana spinor.

  7. A Passage into Critical Theory.

    ERIC Educational Resources Information Center

    Lynn, Steven

    1990-01-01

    Shows how a single passage might be handled by New Criticism, structuralism, deconstructionism, psychological criticism, and feminist criticism. Concludes that a plurality of critical approaches is better than a unity of approach. (RS)

  8. The Possibility of Film Criticism.

    ERIC Educational Resources Information Center

    Poague, Leland; Cadbury, William

    1989-01-01

    Examines the role of critical language in film criticism. Compares and contrasts Monroe Beardsley's philosophy on film aesthetics with the New Criticism. Outlines some of the contributions Beardsley has made to the study of film criticism. (KM)

  9. Teaching Critical Thinking in Undergraduate Science Courses

    NASA Astrophysics Data System (ADS)

    Hager, Paul; Sleet, Ray; Logan, Peter; Hooper, Mal

    This paper reports on the design and evaluation of a project aimed at fostering the critical thinking abilities and dispositions of first year students at an Australian university. Novel paper and pencil problems were designed to foster the range of critical thinking abilities identified by Ennis (1991). Most of these critical thinking tasks relate to applications of chemistry and physics in everyday life. Some of the tasks were developed from information and/or ideas obtained from critical incident interviews with scientists in private and government organisations. The first year university students were required to attempt the tasks in co-operative groups and to interact in these groups in ways aimed at fostering the dispositions of Ennis' ideal critical thinker (Ennis 1996).The project was evaluated from discussions with groups of students, from comments of tutors who observed the students working in groups and from a questionnaire. Evidence obtained from these data indicated that many students considered their thinking skills were enhanced by their experience of attempting the tasks in small co-operative groups.

  10. Critical Casimir forces along the isofields.

    PubMed

    Zubaszewska, M; Maciołek, A; Drzewiński, A

    2013-11-01

    Using quasiexact numerical density-matrix renormalization-group techniques we calculate the critical Casimir force for a two-dimensional (2D) Ising strip with equal strong surface fields, along the thermodynamic paths corresponding to the fixed nonzero bulk field h≠0. Using the Derjaguin approximation we also determine the critical Casimir force and its potential for two disks. We find that varying the temperature along the isofields lying between the bulk coexistence and the capillary condensation critical point leads to a dramatic increase of the critical Casimir interactions with a qualitatively different functional dependence on the temperature than along h=0. These findings might be of relevance for biomembranes, whose heterogeneity is recently interpreted as being connected with a critical behavior belonging to the 2D Ising universality class.

  11. Critical Casimir forces along the isofields

    NASA Astrophysics Data System (ADS)

    Zubaszewska, M.; Maciołek, A.; Drzewiński, A.

    2013-11-01

    Using quasiexact numerical density-matrix renormalization-group techniques we calculate the critical Casimir force for a two-dimensional (2D) Ising strip with equal strong surface fields, along the thermodynamic paths corresponding to the fixed nonzero bulk field h≠0. Using the Derjaguin approximation we also determine the critical Casimir force and its potential for two disks. We find that varying the temperature along the isofields lying between the bulk coexistence and the capillary condensation critical point leads to a dramatic increase of the critical Casimir interactions with a qualitatively different functional dependence on the temperature than along h=0. These findings might be of relevance for biomembranes, whose heterogeneity is recently interpreted as being connected with a critical behavior belonging to the 2D Ising universality class.

  12. Parity-time-symmetric quantum critical phenomena

    PubMed Central

    Ashida, Yuto; Furukawa, Shunsuke; Ueda, Masahito

    2017-01-01

    Synthetic non-conservative systems with parity-time (PT) symmetric gain–loss structures can exhibit unusual spontaneous symmetry breaking that accompanies spectral singularity. Recent studies on PT symmetry in optics and weakly interacting open quantum systems have revealed intriguing physical properties, yet many-body correlations still play no role. Here by extending the idea of PT symmetry to strongly correlated many-body systems, we report that a combination of spectral singularity and quantum criticality yields an exotic universality class which has no counterpart in known critical phenomena. Moreover, we find unconventional low-dimensional quantum criticality, where superfluid correlation is anomalously enhanced owing to non-monotonic renormalization group flows in a PT-symmetry-broken quantum critical phase, in stark contrast to the Berezinskii–Kosterlitz–Thouless paradigm. Our findings can be experimentally tested in ultracold atoms and predict critical phenomena beyond the Hermitian paradigm of quantum many-body physics. PMID:28593991

  13. Nutrition in critical care.

    PubMed

    Bartlett, Robert H; Dechert, Ronald E

    2011-06-01

    Critical care has evolved from a prolonged recovery room stay for cardiac surgery patients to a full medical and nursing specialty in the last 5 decades. The ability to feed patients who cannot eat has evolved from impossible to routine clinical practice in the last 4 decades. Nutrition in critically ill patients based on measurement of metabolism has evolved from a research activity to clinical practice in the last 3 decades. The authors have been involved in this evolution and this article discusses past, present, and likely future practices in nutrition in critically ill patients.

  14. Greening critical care.

    PubMed

    Chapman, Martin; Chapman, Alison

    2011-01-01

    Climate change and environmental stewardship are phrases that have been defining the past few decades and promoting change in our societies. The sensitivities of intensive care as a specialty make the process of greening an intensive care unit a challenge, but not one that is insurmountable. This paper discusses opportunities for critical care to reduce its environmental impact and provide a framework change. The article includes suggestions of what can be done as an individual, as a unit and as a hospital. Generally, practices in critical care are accepted without questioning the environmental consequences. We believe it is time for change, and critical care should give environmental stewardship a higher priority.

  15. Mission Critical Networking

    SciTech Connect

    Eltoweissy, Mohamed Y.; Du, David H.C.; Gerla, Mario; Giordano, Silvia; Gouda, Mohamed; Schulzrinne, Henning; Youssef, Moustafa

    2010-06-01

    Mission-Critical Networking (MCN) refers to networking for application domains where life or livelihood may be at risk. Typical application domains for MCN include critical infrastructure protection and operation, emergency and crisis intervention, healthcare services, and military operations. Such networking is essential for safety, security and economic vitality in our complex world characterized by uncertainty, heterogeneity, emergent behaviors, and the need for reliable and timely response. MCN comprise networking technology, infrastructures and services that may alleviate the risk and directly enable and enhance connectivity for mission-critical information exchange among diverse, widely dispersed, mobile users.

  16. Critical illness myopathy.

    PubMed

    Latronico, Nicola; Tomelleri, Giuliano; Filosto, Massimiliano

    2012-11-01

    To describe the incidence, major risk factors, and the clinical, electrophysiological, and histological features of critical illness myopathy (CIM). Major pathogenetic mechanisms and long-term consequences of CIM are also reviewed. CIM is frequently associated with critical illness polyneuropathy (CIP), and may have a relevant impact on patients' outcome. CIM has an earlier onset than CIP, and recovery is faster. Loss of myosin filaments on muscle biopsy is important to diagnose CIM, and has a good prognosis. Critical illness, use of steroids, and immobility concur in causing CIM. A rationale diagnostic approach to CIM using clinical, electrophysiological, and muscle biopsy investigations is important to plan adequate therapy and to predict recovery.

  17. Complexity, contingency, and criticality.

    PubMed Central

    Bak, P; Paczuski, M

    1995-01-01

    Complexity originates from the tendency of large dynamical systems to organize themselves into a critical state, with avalanches or "punctuations" of all sizes. In the critical state, events which would otherwise be uncoupled become correlated. The apparent, historical contingency in many sciences, including geology, biology, and economics, finds a natural interpretation as a self-organized critical phenomenon. These ideas are discussed in the context of simple mathematical models of sandpiles and biological evolution. Insights are gained not only from numerical simulations but also from rigorous mathematical analysis. Images Fig. 3 Fig. 4 PMID:11607561

  18. A holographic critical point

    SciTech Connect

    DeWolfe, Oliver; Rosen, Christopher; Gubser, Steven S.

    2011-04-15

    We numerically construct a family of five-dimensional black holes exhibiting a line of first-order phase transitions terminating at a critical point at finite chemical potential and temperature. These black holes are constructed so that the equation of state and baryon susceptibilities approximately match QCD lattice data at vanishing chemical potential. The critical end point in the particular model we consider has temperature 143 MeV and chemical potential 783 MeV. Critical exponents are calculated, with results that are consistent with mean-field scaling relations.

  19. Semiholographic Quantum Criticality

    SciTech Connect

    Jensen, Kristan

    2011-12-02

    We identify the near-critical effective theory (EFT) for a wide class of low-temperature phase transitions found via holography. The EFT is of the semiholographic type and describes both holographic Berezinskii-Kosterlitz-Thouless and second-order transitions with nontrivial scaling. It is a simple generalization of the Ginzburg-Landau-Wilson paradigm to systems with an emergent (or hidden) conformal sector. Having identified the near-critical EFT, we explore its basic phenomenology by computing critical exponents and low-frequency correlators.

  20. Greening critical care

    PubMed Central

    2011-01-01

    Climate change and environmental stewardship are phrases that have been defining the past few decades and promoting change in our societies. The sensitivities of intensive care as a specialty make the process of greening an intensive care unit a challenge, but not one that is insurmountable. This paper discusses opportunities for critical care to reduce its environmental impact and provide a framework change. The article includes suggestions of what can be done as an individual, as a unit and as a hospital. Generally, practices in critical care are accepted without questioning the environmental consequences. We believe it is time for change, and critical care should give environmental stewardship a higher priority. PMID:21635700

  1. Critical Friendship Circles: The Cultural Challenge of Cool Feedback

    ERIC Educational Resources Information Center

    Wachob, Phyllis

    2011-01-01

    A critical friend is a friend who offers critique on practice. Critical Friendship Circles (CFCs) are groups of critical friends who meet for feedback using a protocol. A study with 95 participants at an American university in Egypt has revealed challenges specific to the culture of most "Teaching English as a Foreign Language"…

  2. Computer Software Training and HRD: What Are the Critical Issues?

    ERIC Educational Resources Information Center

    Altemeyer, Brad

    2005-01-01

    The paper explores critical issues for HRD practice from a parsonian framework across the HRD legs of organizational development, adult learning, and training and development. Insights into the critical issues emerge from this approach. Identifying successful transfer of training to be critical for organizational, group, and individual success.…

  3. Critical Friendship Circles: The Cultural Challenge of Cool Feedback

    ERIC Educational Resources Information Center

    Wachob, Phyllis

    2011-01-01

    A critical friend is a friend who offers critique on practice. Critical Friendship Circles (CFCs) are groups of critical friends who meet for feedback using a protocol. A study with 95 participants at an American university in Egypt has revealed challenges specific to the culture of most "Teaching English as a Foreign Language"…

  4. Transformative Professional Learning: Embedding Critical Literacies in the Classroom

    ERIC Educational Resources Information Center

    Sangster, Pauline; Stone, Kelly; Anderson, Charles

    2013-01-01

    This article reports on part of a wider study in which a group of teachers opted for a new model of continuing professional development (CPD) that was offered by one local authority (LA) in Scotland. In collaboration with the LA, the teachers selected the topic of critical literacy and the critical pedagogies that develop from a critical literacy…

  5. Practice What You Preach: Using Critical Incidents to Involve Participants.

    ERIC Educational Resources Information Center

    Lagravier, Sharon H.; Beatty, Paulette T.

    The critical incidents method is an instructional method that is particularly suited for use with adult learners. The method involves the following sequence of activities: brief introduction to the subject under consideration, short explanation of the critical incident technique, presentation of the critical incident and directions, group work and…

  6. Critical Infrastructures: Background, Policy, and Implementation

    DTIC Science & Technology

    2008-10-10

    Government Accountability Office, Critical Infrastructure Protection: Challenges for Selected Agencies and Industry Sectors. Repot to the Committee on...set up groups within the federal government to develop and implement plans that would protect government -operated infrastructures and called for a...dialogue between government and the private sector to develop a National Infrastructure Assurance Plan that would protect all of the nation’s critical

  7. Investigating Cell Criticality

    NASA Astrophysics Data System (ADS)

    Serra, R.; Villani, M.; Damiani, C.; Graudenzi, A.; Ingrami, P.; Colacci, A.

    Random Boolean networks provide a way to give a precise meaning to the notion that living beings are in a critical state. Some phenomena which are observed in real biological systems (distribution of "avalanches" in gene knock-out experiments) can be modeled using random Boolean networks, and the results can be analytically proven to depend upon the Derrida parameter, which also determines whether the network is critical. By comparing observed and simulated data one can then draw inferences about the criticality of biological cells, although with some care because of the limited number of experimental observations. The relationship between the criticality of a single network and that of a set of interacting networks, which simulate a tissue or a bacterial colony, is also analyzed by computer simulations.

  8. Critical chemotactic collapse

    NASA Astrophysics Data System (ADS)

    Lushnikov, Pavel M.

    2010-04-01

    A Keller-Segel model describes macroscopic dynamics of bacterial colonies and biological cells as well as dynamics of a gas of self-gravitating Brownian particles. Bacteria secret chemical which attracts other bacteria so that they move towards chemical gradient creating nonlocal attraction between bacteria. If bacterial (or Brownian particle) density exceeds a critical value then the density collapses (blows up) in a finite time which corresponds to bacterial aggregation or gravitational collapse. Collapse in the Keller-Segel model has striking qualitative similarities with a nonlinear Schrödinger equation including critical collapse in two dimensions and supercritical collapse in three dimensions. A self-similar solution near blow up point is studied in the critical two-dimensional case and it has a form of a rescaled steady state solution which contains a critical number of bacteria. Time dependence of scaling of that solution has square root scaling law with logarithmic modification.

  9. Critical Access Hospitals (CAH)

    MedlinePlus

    ... Access Hospital from CMS and Critical Access Hospital Finance 101 Manual from TASC. Furthermore, the Joint Commission ... Hospital Mortgage Insurance Program – helps rural healthcare facilities finance new construction, refinance debt, or purchase new equipment ...

  10. Critical Limb Ischemia (CLI)

    MedlinePlus

    ... High blood pressure Family history of vascular disease Warning Signs You may have critical limb ischemia if ... blood flow to the limb. Other treatments include laser atherectomy, where small bits of plaque are vaporized ...

  11. About critical thinking.

    PubMed

    Hynes, Patricia; Bennett, Jocelyn

    2004-01-01

    Although a universally accepted definition of critical thinking has yet to be determined, there is much discussion in the literature about its meaning and, in particular, how it can be expressed in professional nursing practice. The simultaneous use of related terms such as reflective thinking, problem solving and clinical decision-making contributes to the lack of clarity around exactly what critical thinking is and, subsequently, how it can be taught and evaluated in the clinical setting. The purpose of this article is to provide an overview of the various components of critical thinking and to discuss barriers, facilitators and strategies that can enhance nurses' attainment of this core competency. Few would argue that registered nurses today must be able to think critically in order to effectively communicate a nursing perspective that reflects a meaningful clinical grasp and preparedness to act.

  12. CRITICALITY SAFETY POSTING GUIDELINES

    SciTech Connect

    JENSEN, M.A.

    2001-11-01

    This document provides a set of guidelines in the preparation of criticality safety postings. Guidance is provided in word choice, word arrangement, common human factors considerations. and use of color to highlight limits, cautions, and permissives.

  13. The Critical Thinking Workout.

    ERIC Educational Resources Information Center

    Masters, Terry McDaniel

    1991-01-01

    Presents a critical thinking exercise program, modeled on a physical exercise workout, for elementary teachers to use in the classroom. It includes warm-up exercises, a more strenuous workout, and a cool-down period for the brain. (SM)

  14. Art Criticism and Reading.

    ERIC Educational Resources Information Center

    Feldman, Edmund Burke; Woods, Don

    1981-01-01

    The authors review a body of theory and accumulating evidence which suggests that critical study of the arts facilitates the development of cognitive skills, including those essential to reading. (Author/SJL)

  15. The Critical Thinking Workout.

    ERIC Educational Resources Information Center

    Masters, Terry McDaniel

    1991-01-01

    Presents a critical thinking exercise program, modeled on a physical exercise workout, for elementary teachers to use in the classroom. It includes warm-up exercises, a more strenuous workout, and a cool-down period for the brain. (SM)

  16. Critical Limb Ischemia (CLI)

    MedlinePlus

    ... Get Involved Get Involved Resources Educational Flyers Video Library Types of Vascular Diseases Papers & Presentations News News Items Press Releases Newsletters Events Donate Donate Now Ways to Give Individual Donors Corporate Sponsors Donor Privacy Policy Critical Limb Ischemia (CLI) ...

  17. Critical Viscosity of Xenon

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The Critical Viscosity of Xenon Experiment (CVX-2) on the STS-107 Research 1 mission in 2002 will measure the viscous behavior of xenon, a heavy inert gas used in flash lamps and ion rocket engines, at its critical point. Shear thirning will cause a normally viscous fluid -- such as pie filling or whipped cream -- to deform and flow more readily under high shear conditions. In shear thinning, a pocket of fluid will deform and move one edge forward, as depicted here.

  18. Critical Viscosity of Xenon

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The Critical Viscosity of Xenon Experiment (CVX-2) on the STS-107 Research 1 mission in 2002 will measure the viscous behavior of xenon, a heavy inert gas used in flash lamps and ion rocket engines, at its critical point. Shear thirning will cause a normally viscous fluid -- such as pie filling or whipped cream -- to deform and flow more readily under high shear conditions. In shear thinning, a pocket of fluid will deform and move one edge forward, as depicted here.

  19. Marketing audit in group practice.

    PubMed

    Blackburn, J M

    1984-01-01

    The marketing audit, whether large-scale or small-scale, will soon be critical to the success of every medical group practice. This dynamic process, in which the many components of a group's marketing efforts are analyzed, is examined from the perspective of ideal circumstances and unlimited resources, and more pragmatically, from the perspective of various-sized groups, with different resources and marketing talent. The audit components are prioritized, possible adaptations and combinations are presented, and reasonable implementation mechanisms, designed to address audit outcomes, are suggested.

  20. Demonstrating Group Process Using "12 Angry Men"

    ERIC Educational Resources Information Center

    Armstrong, Stephen A.; Berg, Robert C.

    2005-01-01

    The feature film "12 Angry Men" focuses on an organizational task group that demonstrates the dynamics of a working group. The film is discussed as an effective tool for illuminating group process. The authors describe their experiences using the movie as a teaching tool and provide examples of how it can be used to depict critical incidents, the…