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Sample records for critical group icrp

  1. Radiological Protection in Space: Indication from the ICRP Task Group

    NASA Astrophysics Data System (ADS)

    Dietze, Günther

    In 2007 the International Commission on Radiological Protection (ICRP) has established a Task Group (Radiation Protection in Space) dealing with the problems of radiation protection of astronauts in space missions. Its first task is a report on "Assessment of Radiation Exposure of Astronauts in Space". When the ICRP published its general recommendations for radiological protection in 2007 (ICRP Publication 103 following ICRP Publication 60 (1991)) it was obvious that these recommendations do not really consider the special situation of astronauts in space. The radiation field with its high content of charged particles of very high energies strongly differs from usual radiation fields on ground. For example, this has consequences for the assessment of doses in the body of astronauts. The ICRP Task Group has discussed this situation and the presentation will deal with some consequences for the concept of radiation dosimetry and radiological protection in space. This includes e. g. the assessment of organ doses and the application of the effective dose concept with its definition of radiation weighting factors. Radiation quality of high energy heavy ions may be defined different than usually performed on ground. An approach of using the quality factor concept in the definition of an "effective dose" is favored for application in space missions similar to the method proposed in NCRP Report 142. New data calculated on the basis of the reference anthropomorphic voxel phantoms recommended by ICRP support this procedure. Individual dosimetry is a further subject of discussion in the Task Group. While the operational dose equivalent quantities generally in use in radiation protection on ground are not helpful for applications in space, different procedures of the assessment of organ and effective doses are applied. The Task Group is dealing with this situation.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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)

  8. 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. PMID:14526956

  9. Attempted validation of ICRP 30 and ICRP 66 respiratory models.

    PubMed

    Harley, N H; Fisenne, I M; Robbins, E S

    2012-11-01

    The validation of human biological models for inhaled radionuclides is nearly impossible. Requirements for validation are: (1) the measurement of the relevant human tissue data and (2) valid exposure measurements over the interval known to apply to tissue uptake. Two lung models, ICRP 30(1) and ICRP 66(2), are widely used to estimate lung doses following acute occupational or environmental exposure. Both ICRP 30 and 66 lung models are structured to estimate acute rather than chronic exposure. Two sets of human tissue measurements are available: (210)Po accumulated in tissue from inhaled cigarettes and ingested in diet and airborne global fallout (239,240)Pu accumulated in the lungs from inhalation. The human tissue measurements include pulmonary and bronchial tissue in smokers, ex-smokers and non-smokers analysed radiochemically for (210)Po, and pulmonary, bronchial and lymph nodes analysed for (239,240)Pu in lung tissue collected by the New York City Medical Examiner from 1972 to 1974. Both ICRP 30 and 66 models were included in a programme to accommodate chronic uptake. Neither lung model accurately described the estimated tissue concentrations but was within a factor of 2 from measurements. ICRP 66 was the exception and consistently overestimated the bronchial concentrations probably because of its assumption of an overly long 23-d clearance half-time in the bronchi and bronchioles. PMID:22923255

  10. Update of ICRP Publications 109 and 111.

    PubMed

    Kai, Michiaki

    2016-02-01

    The Task Group (TG) of Committee 4 was created to update the International Commission on Radiological Protection (ICRP) Publications 109 and 111 in light of the lessons from Fukushima, recent international developments concerning the protection of people in emergency exposure situations, and people living in long-term contaminated areas after a nuclear accident or a radiation emergency. An important aspect of the TG's approach focuses on clarifying the consequences of the introduction of the situation-based approach to implementation of radiological protection that was introduced in ICRP Publication 103 in place of the previous approach based on the distinction between practices and interventions. The TG focused its reflection on several issues revealed by the Fukushima accident in relation to the justification and optimization of emergency decisions, the characterization of the radiological situation, the protection of emergency and recovery responders, the decontamination and waste management strategies, the management of contaminated foodstuffs and commodities, the shift from the emergency to the existing exposure situation, and the co-expertise process to develop radiological protection culture among the affected population. PMID:26717182

  11. 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

  12. 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.

  13. Critical Reaction to Personal Mastery Group Counseling.

    ERIC Educational Resources Information Center

    Ellis, Albert

    1978-01-01

    Reviews seven previous articles on Personal Mastery Group Counseling and discusses their main advantages and disadvantages. The relationship of Personal Mastery Group Counseling to Rational-Emotive Therapy is also considered. (Author)

  14. 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…

  15. Updating the ICRP human respiratory tract model.

    PubMed

    Bailey, M R; Ansoborlo, E; Guilmette, R A; Paquet, F

    2007-01-01

    The ICRP Task Group on Internal Dosimetry is developing new Occupational Intakes of Radionuclides (OIR) documents. Application of the Human Respiratory Tract Model (HRTM) requires a review of the lung-to-blood absorption characteristics of inhaled compounds of importance in radiological protection. Where appropriate, material-specific absorption parameter values will be given, and for other compounds, assignments to default Types will be made on current information. Publication of the OIR provides an opportunity for updating the HRTM in the light of experience and new information. The main possibilities under consideration relate to the two main clearance pathways. Recent studies provide important new data on rates of particle transport from the nasal passages, bronchial tree (slow phase) and alveolar region. The review of absorption rates provides a database of parameter values from which consideration can be given to deriving typical values for default Types F, M and S materials, and element-specific rapid dissolution rates. PMID:18192668

  16. 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.

  17. Overview of ICRP Committee 2 'Doses from Radiation Exposure'.

    PubMed

    Harrison, J

    2015-06-01

    Over many years, Committee 2 of the International Commission on Radiological Protection (ICRP) has provided sets of dose coefficients to allow users to evaluate equivalent and effective doses for intakes of radionuclides or exposure to external radiation for comparison with dose limits, constraints, and reference levels as recommended by ICRP. Following the 2007 Recommendations, Committee 2 and its task groups are engaged in a substantial programme of work to provide new dose coefficients for various conditions of radiation exposure. The methodology being applied in the calculation of doses can be regarded as state-of-the-art in terms of the biokinetic models used to describe the behaviour of inhaled and ingested radionuclides, and the dosimetric models used to model radiation transport for external and internal exposures. The level of sophistication of these models is greater than required for calculation of the protection quantities with their inherent simplifications and approximations, which were introduced necessarily, for example by the use of radiation and tissue weighting factors. However, ICRP is at the forefront of developments in this area, and its models are used for scientific as well as protection purposes. This overview provides an outline of recent work and future plans, including publications on dose coefficients for adults, children, and in-utero exposures, with new dosimetric phantoms in each case. The Committee has also recently finished a report on radiation exposures of astronauts in space, and is working with members of the other ICRP committees on the development of advice on the use of effective dose.

  18. 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. PMID:26626286

  19. 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).

  20. Group Discussion and Individual Critical Thinking Processes: An Interactive Perspective.

    ERIC Educational Resources Information Center

    Dixson, Marcia D.

    This paper offers a small group discussion model as a viable alternative for facilitating critical thinking. The paper first review literature discussing what critical thinking is and whether it can be taught. After defining critical thinking as an active process which involves constructing arguments, the paper concludes that an optimally…

  1. 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.…

  2. Still Learning about Leading: A Leadership Critical Friends Group

    ERIC Educational Resources Information Center

    Fahey, Kevin M.

    2011-01-01

    This case study examines how a group of early career school leaders used a particular model of professional learning, the Critical Friends Group (The School Reform Initiative, 2010), to continue to learn about leading. More specifically, this study offers an in-depth look at how the use of a structured conversation or protocol, designed to build…

  3. ICRP Publication 119: Compendium of dose coefficients based on ICRP Publication 60.

    PubMed

    Eckerman, K; Harrison, J; Menzel, H-G; Clement, C H

    2012-01-01

    This report is a compilation of dose coefficients for intakes of radionuclides by workers and members of the public, and conversion coefficients for use in occupational radiological protection against external radiation from Publications 68, 72, and 74 (ICRP, 1994b, 1996a,b). It serves as a comprehensive reference for dose coefficients based on the primary radiation protection guidance given in the Publication 60 recommendations (ICRP, 1991). The coefficients tabulated in this publication will be superseded in due course by values based on the Publication 103 recommendations (ICRP, 2007). PMID:23025851

  4. ICRP Publication 116—the first ICRP/ICRU application of the male and female adult reference computational phantoms

    NASA Astrophysics Data System (ADS)

    Petoussi-Henss, Nina; Bolch, Wesley E.; Eckerman, Keith F.; Endo, Akira; Hertel, Nolan; Hunt, John; Menzel, Hans G.; Pelliccioni, Maurizio; Schlattl, Helmut; Zankl, Maria

    2014-09-01

    ICRP Publication 116 on ‘Conversion coefficients for radiological protection quantities for external radiation exposures’, provides fluence-to-dose conversion coefficients for organ-absorbed doses and effective dose for various types of external exposures (ICRP 2010 ICRP Publication 116). The publication supersedes the ICRP Publication 74 (ICRP 1996 ICRP Publication 74, ICRU 1998 ICRU Report 57), including new particle types and expanding the energy ranges considered. The coefficients were calculated using the ICRP/ICRU computational phantoms (ICRP 2009 ICRP Publication 110) representing the reference adult male and reference adult female (ICRP 2002 ICRP Publication 89), together with a variety of Monte Carlo codes simulating the radiation transport in the body. Idealized whole-body irradiation from unidirectional and rotational parallel beams as well as isotropic irradiation was considered for a large variety of incident radiations and energy ranges. Comparison of the effective doses with operational quantities revealed that the latter quantities continue to provide a good approximation of effective dose for photons, neutrons and electrons for the ‘conventional’ energy ranges considered previously (ICRP 1996, ICRU 1998), but not at the higher energies of ICRP Publication 116.

  5. ICRP Publication 116--the first ICRP/ICRU application of the male and female adult reference computational phantoms.

    PubMed

    Petoussi-Henss, Nina; Bolch, Wesley E; Eckerman, Keith F; Endo, Akira; Hertel, Nolan; Hunt, John; Menzel, Hans G; Pelliccioni, Maurizio; Schlattl, Helmut; Zankl, Maria

    2014-09-21

    ICRP Publication 116 on 'Conversion coefficients for radiological protection quantities for external radiation exposures', provides fluence-to-dose conversion coefficients for organ-absorbed doses and effective dose for various types of external exposures (ICRP 2010 ICRP Publication 116). The publication supersedes the ICRP Publication 74 (ICRP 1996 ICRP Publication 74, ICRU 1998 ICRU Report 57), including new particle types and expanding the energy ranges considered. The coefficients were calculated using the ICRP/ICRU computational phantoms (ICRP 2009 ICRP Publication 110) representing the reference adult male and reference adult female (ICRP 2002 ICRP Publication 89), together with a variety of Monte Carlo codes simulating the radiation transport in the body. Idealized whole-body irradiation from unidirectional and rotational parallel beams as well as isotropic irradiation was considered for a large variety of incident radiations and energy ranges. Comparison of the effective doses with operational quantities revealed that the latter quantities continue to provide a good approximation of effective dose for photons, neutrons and electrons for the 'conventional' energy ranges considered previously (ICRP 1996, ICRU 1998), but not at the higher energies of ICRP Publication 116. PMID:25144220

  6. Creating Moral Schools: The Enabling Potential of Critical Friends Groups

    ERIC Educational Resources Information Center

    Law, Bruce

    2005-01-01

    Critical Friends Groups (CFGs) are vehicles for creating collective intentionality that reaches a shared end: increased opportunity for the disadvantaged to create equality of opportunity. Not that participating in CFGs is the only action educators can take to create moral schools; rather, moral schools reflect the beliefs, ends, and practices…

  7. United States Critical Illness and Injury Trials Group.

    PubMed

    Blum, James M; Morris, Peter E; Martin, Greg S; Gong, Michelle N; Bhagwanjee, Satish; Cairns, Charles B; Cobb, J Perren

    2013-03-01

    The United States Critical Illness and Injury Trials (USCIIT) Group is an inclusive, grassroots "network of networks" with the dual missions of fostering investigator-initiated hypothesis testing and developing recommendations for strategic plans at a national level. The USCIIT Group's transformational approach enlists multidisciplinary investigative teams across institutions, critical illness and injury professional organizations, federal agencies that fund clinical and translational research, and industry partners. The USCIIT Group is endorsed by all major critical illness and injury professional organizations spanning the specialties of anesthesiology, emergency medicine, internal medicine, neurology, nursing, pediatrics, pharmacy and nutrition, surgery and trauma, and respiratory and physical therapy. Recent successes provide the opportunity to significantly increase the dialogue necessary to advance clinical and translational research on behalf of our community. More than 200 investigators are now involved across > 30 academic and community hospitals. Collectively, USCIIT Group investigators have enrolled > 10,000 patients from academic and community hospitals in studies during the last 3 years. To keep our readership "ahead of the curve," this article provides a vision for critical illness and injury research based on (1) programmatic organization of large-scale, multicentered collaborative studies and (2) annual strategic planning at a national scale across disciplines and stakeholders. PMID:23460158

  8. 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…

  9. Conversion of ICRP male reference phantom to polygon-surface phantom

    NASA Astrophysics Data System (ADS)

    Yeom, Yeon Soo; Han, Min Cheol; Kim, Chan Hyeong; Jeong, Jong Hwi

    2013-10-01

    The International Commission on Radiological Protection (ICRP) reference phantoms, developed based on computed tomography images of human bodies, provide much more realism of human anatomy than the previously used MIRD5 (Medical Internal Radiation Dose) mathematical phantoms. It has been, however, realized that the ICRP reference phantoms have some critical limitations showing a considerable amount of holes for the skin and wall organs mainly due to the nature of voxels of which the phantoms are made, especially due to their low voxel resolutions. To address this problem, we are planning to develop the polygon-surface version of ICRP reference phantoms by directly converting the ICRP reference phantoms (voxel phantoms) to polygon-surface phantoms. The objective of this preliminary study is to see if it is indeed possible to construct the high-quality polygon-surface phantoms based on the ICRP reference phantoms maintaining identical organ morphology and also to identify any potential issues, and technologies to address these issues, in advance. For this purpose, in the present study, the ICRP reference male phantom was roughly converted to a polygon-surface phantom. Then, the constructed phantom was implemented in Geant4, Monte Carlo particle transport code, for dose calculations, and the calculated dose values were compared with those of the original ICRP reference phantom to see how much the calculated dose values are sensitive to the accuracy of the conversion process. The results of the present study show that it is certainly possible to convert the ICRP reference phantoms to surface phantoms with enough accuracy. In spite of using relatively less resources (<2 man-months), we were able to construct the polygon-surface phantom with the organ masses perfectly matching the ICRP reference values. The analysis of the calculated dose values also implies that the dose values are indeed not very sensitive to the detailed morphology of the organ models in the phantom

  10. Improved renormalization group theory for critical asymmetry of fluids

    NASA Astrophysics Data System (ADS)

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

    2013-09-01

    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.

  11. Radiation doses to critical groups since the early 1950`s due to discharges of liquid radioactive waste from Sellafield

    SciTech Connect

    Hunt, G.J.

    1997-04-01

    First, some of the early work is reviewed on exposure pathways in connection with proposed and early liquid radioactive waste discharges from Sellafield. The main historical features of these discharges, affected by relevant plant operations, are then briefly described. The important radiological exposure pathways resulting from the discharges and people`s consumption and occupancy habits are considered. To place the changing scenario onto a consistent basis using present-day methodology, a reconstruction of exposures has been carried out using environmental monitoring data and models. The three major pathways are examined of Porphyral laverbread consumption in South Wales, fish and shellfish consumption near Sellafield, and external exposure over local and more distant sediments. The results show that over the period 1952 to about 1970 the laverbread pathway was probably critical, taking a cautious approach. Effective dose rates fluctuated at around 1 mSv y{sup -1} from about 1956 to 1971. From about 1970 to 1985, the fish and shellfish pathway was likely to have been critical, with effective dose rates peaking at about 2 mSv y{sup -1} in 1975-1976. External exposure was likely to have been of lesser importance than the other two pathways until about 1985, when with the retention of previously-released radiocesium on sediments it has become dominant. This phenomenon applies particularly further afield where radiocesium concentrations have been slower to decline; in the Ribble estuary, houseboat dwellers have been the critical group from about 1985. Effective doses have been at about 0.3 mSv y{sup -1} and declining; they are due to the effects of radiocesium discharges in earlier years. Dose rates have remained within contemporary ICRP dose limits.

  12. Overview of the ICRP/ICRU adult reference computational phantoms and dose conversion coefficients for external idealised exposures.

    PubMed

    Endo, Akira; Petoussi-Henss, Nina; Zankl, Maria; Bolch, Wesley E; Eckerman, Keith F; Hertel, Nolan E; Hunt, John G; Pelliccioni, Maurizio; Schlattl, Helmut; Menzel, Hans-Georg

    2014-10-01

    This paper reviews the ICRP Publications 110 and 116 describing the reference computational phantoms and dose conversion coefficients for external exposures. The International Commission on Radiological Protection (ICRP) in its 2007 Recommendations made several revisions to the methods of calculation of the protection quantities. In order to implement these recommendations, the DOCAL task group of the ICRP developed computational phantoms representing the reference adult male and female and then calculated a set of dose conversion coefficients for various types of idealised external exposures. This paper focuses on the dose conversion coefficients for neutrons and investigates their relationship with the conversion coefficients of the protection and operational quantities of ICRP Publication 74. Contributing factors to the differences between these sets of conversion coefficients are discussed in terms of the changes in phantoms employed and the radiation and tissue weighting factors. PMID:24285286

  13. 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.

  14. 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.

  15. 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.

  16. 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. PMID:22809956

  17. Some Critical Differences between Self-Help and Therapy Groups.

    ERIC Educational Resources Information Center

    Riordan, Richard J.; Beggs, Marilyn S.

    1988-01-01

    Presents a scheme for addressing differences between self-help groups and therapy groups, characterizing a list of group work parameters according to emphasis placed on each in therapy groups in contrast with self-help groups. Distinguishes between support groups, started by professional helping organizations or individuals, and self-help groups,…

  18. 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

  19. 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

  20. 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. PMID:25906251

  1. 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.

  2. ICRP PUBLICATION 120: Radiological protection in cardiology.

    PubMed

    Cousins, C; Miller, D L; Bernardi, G; Rehani, M M; Schofield, P; Vañó, E; Einstein, A J; Geiger, B; Heintz, P; Padovani, R; Sim, K-H

    2013-02-01

    Cardiac nuclear medicine, cardiac computed tomography (CT), interventional cardiology procedures, and electrophysiology procedures are increasing in number and account for an important share of patient radiation exposure in medicine. Complex percutaneous coronary interventions and cardiac electrophysiology procedures are associated with high radiation doses. These procedures can result in patient skin doses that are high enough to cause radiation injury and an increased risk of cancer. Treatment of congenital heart disease in children is of particular concern. Additionally, staff(1) in cardiac catheterisation laboratories may receive high doses of radiation if radiological protection tools are not used properly. The Commission provided recommendations for radiological protection during fluoroscopically guided interventions in Publication 85, for radiological protection in CT in Publications 87 and 102, and for training in radiological protection in Publication 113 (ICRP, 2000b,c, 2007a, 2009). This report is focused specifically on cardiology, and brings together information relevant to cardiology from the Commission's published documents. There is emphasis on those imaging procedures and interventions specific to cardiology. The material and recommendations in the current document have been updated to reflect the most recent recommendations of the Commission. This report provides guidance to assist the cardiologist with justification procedures and optimisation of protection in cardiac CT studies, cardiac nuclear medicine studies, and fluoroscopically guided cardiac interventions. It includes discussions of the biological effects of radiation, principles of radiological protection, protection of staff during fluoroscopically guided interventions, radiological protection training, and establishment of a quality assurance programme for cardiac imaging and intervention. As tissue injury, principally skin injury, is a risk for fluoroscopically guided interventions

  3. 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…

  4. 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

  5. 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.

  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. Guidelines for medical technology in critical care. Technology Subcommittee of the Working Group on Critical Care, Ontario Ministry of Health.

    PubMed Central

    1991-01-01

    OBJECTIVE: To examine the current status of technology in critical care medicine and to present guidelines for technologies commonly used in Ontario critical care units. Data sources: A computerized search of the medical literature, interviews with relevant people and a review of existing guidelines or standards were conducted. STUDY SELECTION: Nonrandomized trials and retrospective reviews were included because of a paucity of prospective randomized controlled trials. Data extraction: Technologies were assessed by individual committee members. The validity of the technologies was compared with accepted standards when available. All published clinical data were used to assess efficacy. DATA SYNTHESIS: After review of the data, discussion papers on ventilation, and electrocardiographic, hemodynamic and intracranial pressure monitoring were written by committee members and then reviewed by the subcommittee as a whole. For each technology an attempt was made to match need with the patient classifications of the Working Group on Critical Care. Critical care guidelines were then developed through the use of the nominal group and Delphi consensus-gathering techniques. The guidelines were reviewed by external experts. CONCLUSIONS: These guidelines should help in assessing quality assurance and the resources necessary for critical care. Also, they should enable health care providers and hospital administrators to make better decisions when acquiring critical care technology. Since the guidelines represent the current state of knowledge there must be a continuing assessment of the technology and review of the guidelines. PMID:1796943

  8. 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.

  9. 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. PMID:26987889

  10. 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

  11. 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

  12. An ICRP-based Chinese adult male voxel model and its absorbed dose for idealized photon exposures--the skeleton.

    PubMed

    Liu, Liye; Zeng, Zhi; Li, Junli; Zhang, Binquan; Qiu, Rui; Ma, Jizeng

    2009-11-01

    A site-specific skeleton voxel model for a Chinese adult male was constructed in this paper upon a previous Chinese individual voxel model. The whole skeleton was divided into 19 site-specific bones and bone groups; the mass of various skeleton tissues at each bone site, e.g. red bone marrow, was specified according to Asian reference data and the distribution data from ICRP Publication 70. The resultant voxel model (called CAM) has a resolution of 1.741 mm x 1.741 mm in plane, and the total bone mass is 8397.8 g which is almost equal to the Asian reference value. Dose coefficients for the red bone marrow and bone surface in CAM were calculated, and then compared with those from Rex, CMP and ICRP 74. It shows that the dose to RBM in Rex is generally 12% lower than that to CAM in low-energy range (30-150 keV) for AP, LAT, ROT and ISO geometries. It is also found that the RBM dose from mathematical models, i.e. CMP and ICRP 74, is underestimated by -30% in AP geometry and overestimated by 30% in PA geometry for low-energy photons. Meanwhile, the bone surface dose in the low-energy range is overestimated by 150% and 75% in CMP and ICRP 74, respectively, if compared with that from CAM. PMID:19841519

  13. An ICRP-based Chinese adult male voxel model and its absorbed dose for idealized photon exposures—the skeleton

    NASA Astrophysics Data System (ADS)

    Liu, Liye; Zeng, Zhi; Li, Junli; Zhang, Binquan; Qiu, Rui; Ma, Jizeng

    2009-11-01

    A site-specific skeleton voxel model for a Chinese adult male was constructed in this paper upon a previous Chinese individual voxel model. The whole skeleton was divided into 19 site-specific bones and bone groups; the mass of various skeleton tissues at each bone site, e.g. red bone marrow, was specified according to Asian reference data and the distribution data from ICRP Publication 70. The resultant voxel model (called CAM) has a resolution of 1.741 mm × 1.741 mm in plane, and the total bone mass is 8397.8 g which is almost equal to the Asian reference value. Dose coefficients for the red bone marrow and bone surface in CAM were calculated, and then compared with those from Rex, CMP and ICRP 74. It shows that the dose to RBM in Rex is generally 12% lower than that to CAM in low-energy range (30-150 keV) for AP, LAT, ROT and ISO geometries. It is also found that the RBM dose from mathematical models, i.e. CMP and ICRP 74, is underestimated by -30% in AP geometry and overestimated by 30% in PA geometry for low-energy photons. Meanwhile, the bone surface dose in the low-energy range is overestimated by 150% and 75% in CMP and ICRP 74, respectively, if compared with that from CAM.

  14. 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.

  15. 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.

  16. 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…

  17. 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.

  18. Tracheostomy in special groups of critically ill patients: Who, when, and where?

    PubMed Central

    Longworth, Aisling; Veitch, David; Gudibande, Sandeep; Whitehouse, Tony; Snelson, Catherine; Veenith, Tonny

    2016-01-01

    Tracheostomy is one of the most common procedures undertaken in critically ill patients. It offers many theoretical advantages over translaryngeal intubation. Recent evidence in a heterogeneous group of critically ill patients, however, has not demonstrated a benefit for tracheostomy, in terms of mortality, length of stay in Intensive Care Unit (ICU), or incidence of ventilator-associated pneumonia. It may be a beneficial intervention in articular subsets of ICU patients. In this article, we will focus on the evidence for the timing of tracheostomy and its effect on various subgroups of patients in critical care. PMID:27275076

  19. Community groups as ‘critical enablers’ of the HIV response in Zimbabwe

    PubMed Central

    2013-01-01

    Background The Investment Framework for a more effective HIV response has become integral to discussions on how best to respond to the HIV epidemic. The Framework calls for greater synergy and attention to factors that serve as ‘critical enablers’ and optimise HIV programmes. In this paper we argue for recognition of informal and indigenous community groups as ‘critical enablers’ of the HIV response. Methods This qualitative study was conducted in Matobo district of the Matabeleland South province in Zimbabwe. It draws on 19 individual in-depth interviews and 9 focus group discussions conducted by local researchers in September and October 2011. Data was thematically analysed. Results Four core themes highlight the possibilities and limitations of community groups in the HIV response: (i) Membership of indigenous community groups and group-based dialogue were found to encourage group members to engage with HIV prevention, mitigation and care efforts; (ii) local networks and partnerships between groups and NGOs were said to play an important role in accessing much needed resources to aid indigenous coping with AIDS; (iii) community strengths and resources were recognised and drawn upon in the community group response; (iv) frequent droughts, poverty and stigma served as obstacles to an effective HIV response. Conclusions In this context, social groups, although to varying degrees and in direct or indirect ways, play a key role in the HIV response. This suggest that community groups and networks can indeed act as ‘critical enablers’ to the HIV response, and that efforts need to be made to facilitate the contributions of already existing indigenous responses. Local community groups are developing local and collective solutions to structural problems, often independently of external NGO or health service efforts, and begging for synergy and collaboration between local community groups and networks, the health services and other external HIV service delivery

  20. The critical value of focus group discussions in research with women living with HIV in Malawi.

    PubMed

    Mkandawire-Valhmu, Lucy; Stevens, Patricia E

    2010-05-01

    This article is based on a critical ethnography about HIV and gender-based issues of power and violence conducted in Malawi in 2008. In all, 72 women living with HIV were recruited from four antiretroviral treatment clinics, three rural and one urban, to participate in 12 focus groups. Informed by a postcolonial feminist perspective, we analyze the process and products of these focus groups to interrogate their capacity to facilitate collective engagement with the social and structural realities confronting women in a resource-limited, highly AIDS-affected country. We present exemplars to show how women together created collective narratives to mobilize individuals to action. Findings indicate that focus groups can be used innovatively to benefit both the research and the participants, not only as a critical method of inquiry with marginalized groups but also as a forum in which validating dialogue, mutual support, and exchange of strategic information can generate transformative change to improve women's lives.

  1. 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…

  2. 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…

  3. 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…

  4. 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 illustrate…

  5. Augmentation of hospital critical care capacity after bioterrorist attacks or epidemics: recommendations of the Working Group on Emergency Mass Critical Care.

    PubMed

    Rubinson, Lewis; Nuzzo, Jennifer B; Talmor, Daniel S; O'Toole, Tara; Kramer, Bradley R; Inglesby, Thomas V

    2005-10-01

    The Working Group on Emergency Mass Critical Care was convened by the Center for Biosecurity of the University of Pittsburgh Medical Center and the Society of Critical Care Medicine to provide recommendations to hospital and clinical leaders regarding the delivery of critical care services in the wake of a bioterrorist attack resulting in hundreds or thousands of critically ill patients. In these conditions, traditional hospital and clinical care standards in general, and critical care standards in particular, likely could no longer be maintained, and clinical guidelines for U.S. hospitals facing these situations have not been developed. The Working Group offers recommendations for this situation.

  6. DOE Spent Nuclear Fuel Group in Support of Criticality, DBE, TSPA-LA

    SciTech Connect

    Henry Loo

    2000-05-01

    This report presents the basis for grouping the over 250 Department of Energy (DOE) spent nuclear fuel (SNF) types in support of analyses for final repository disposal. For each of the required analyses, the parameters needed in conducting the analyses were identified and reviewed. The grouping proposed for the three types of analyses (criticality, design basis events, and total system performance assessment) are based on the similarities of DOE SNF as a function of these parameters. As necessary, further justifications are provided to further reduce the DOE SNF grouping in support of the Office of Civilian Radioactive Waste Management System’s preclosure and postclosure safety cases.

  7. 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.

  8. 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.

  9. 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

  10. The effect of ICRP (74) on the response of neutron monitors

    NASA Astrophysics Data System (ADS)

    Leake, J. W.

    1999-01-01

    The response of the 0075 family of spherical neutron detectors is discussed in the light of the latest fluence to dose conversion factors in ICRP 74 (1996). It is concluded that the detector response is a marginally better fit to these recommendations than to the earlier ones in ICRP 21 (1973) and that no change in calibration is required.

  11. Algorithms for detecting concealed knowledge among groups when the critical information is unavailable.

    PubMed

    Breska, Assaf; Ben-Shakhar, Gershon; Gronau, Nurit

    2012-09-01

    We examined whether the Concealed Information Test (CIT) may be used when the critical details are unavailable to investigators (the Searching CIT [SCIT]). This use may have important applications in criminal investigations (e.g., finding the location of a murder weapon) and in security-related threats (e.g., detecting individuals and groups suspected in planning a terror attack). Two classes of algorithms designed to detect the critical items and classify individuals in the SCIT were examined. The 1st class was based on averaging responses across subjects to identify critical items and on averaging responses across the identified critical items to identify knowledgeable subjects. The 2nd class used clustering methods based on the correlations between the response profiles of all subject pairs. We applied a principal component analysis to decompose the correlation matrix into its principal components and defined the detection score as the coefficient of each subject on the component that explained the largest portion of the variance. Reanalysis of 3 data sets from previous CIT studies demonstrated that in most cases the efficiency of differentiation between knowledgeable and unknowledgeable subjects in the SCIT (indexed by the area under the receiver operating characteristic curve) approached that of the standard CIT for both algorithms. We also examined the robustness of our results to variations in the number of knowledgeable and unknowledgeable subjects in the sample. This analysis demonstrated that the performance of our algorithms is relatively robust to changes in the number of individuals examined in each group, provided that at least 2 (but desirably 5 or more) knowledgeable examinees are included.

  12. 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.

  13. International studies on burnup credit criticality safety by an OECD/NEA working group

    SciTech Connect

    Brady, M.C.; Okuno, H.; DeHart, M.D.; Nouri, A.; Sartori, E.

    1998-11-01

    The results and conclusions from a six-year study by an international benchmarking group in the comparison of computational methods for evaluating burnup credit in criticality safety analyses is presented. Approximately 20 participants from 12 countries have provided results for most problems. Four detailed benchmark problems for pressurized-water-reactor fuel have been completed. Results from work being finalized, addressing burnup credit for boiling-water-reactor fuel, are discussed, as well as planned activities for additional benchmarks, including mixed-oxide fuels, and other activities.

  14. 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.

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

    PubMed

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

    2000-06-01

    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.

  16. 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. PMID:17557893

  17. 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.

  18. 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. PMID:23799773

  19. 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.

  20. 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.

  1. Overview of ICRP Committee 2: doses from radiation exposure.

    PubMed

    Harrison, J D; Paquet, F

    2016-06-01

    The focus of the work of Committee 2 of the International Commission on Radiological Protection (ICRP) is the computation of dose coefficients compliant with Publication 103 A set of reference computational phantoms is being developed, based on medical imaging data, and used for radiation transport calculations. Biokinetic models used to describe the behaviour of radionuclides in body tissues are being updated, also leading to changes in organ doses and effective dose coefficients. Dose coefficients for external radiation exposure of adults calculated using the new reference phantoms were issued as Publication 116, jointly with the International Commission on Radiation Units and Measurements. Forthcoming reports will provide internal dose coefficients for radionuclide inhalation and ingestion by workers, and associated bioassay data. Work is in progress to revise internal dose coefficients for members of the public, and, for the first time, to provide reference values for external exposures of the public. Committee 2 is also working with Committee 3 on dose coefficients for radiopharmaceuticals, and leading a cross-Committee initiative to give advice on the use of effective dose. PMID:26984902

  2. Overview of ICRP Committee 2: doses from radiation exposure.

    PubMed

    Harrison, J D; Paquet, F

    2016-06-01

    The focus of the work of Committee 2 of the International Commission on Radiological Protection (ICRP) is the computation of dose coefficients compliant with Publication 103 A set of reference computational phantoms is being developed, based on medical imaging data, and used for radiation transport calculations. Biokinetic models used to describe the behaviour of radionuclides in body tissues are being updated, also leading to changes in organ doses and effective dose coefficients. Dose coefficients for external radiation exposure of adults calculated using the new reference phantoms were issued as Publication 116, jointly with the International Commission on Radiation Units and Measurements. Forthcoming reports will provide internal dose coefficients for radionuclide inhalation and ingestion by workers, and associated bioassay data. Work is in progress to revise internal dose coefficients for members of the public, and, for the first time, to provide reference values for external exposures of the public. Committee 2 is also working with Committee 3 on dose coefficients for radiopharmaceuticals, and leading a cross-Committee initiative to give advice on the use of effective dose.

  3. 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.

  4. 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.

  5. Conducting a critical interpretive synthesis of the literature on access to healthcare by vulnerable groups

    PubMed Central

    Dixon-Woods, Mary; Cavers, Debbie; Agarwal, Shona; Annandale, Ellen; Arthur, Antony; Harvey, Janet; Hsu, Ron; Katbamna, Savita; Olsen, Richard; Smith, Lucy; Riley, Richard; Sutton, Alex J

    2006-01-01

    Background Conventional systematic review techniques have limitations when the aim of a review is to construct a critical analysis of a complex body of literature. This article offers a reflexive account of an attempt to conduct an interpretive review of the literature on access to healthcare by vulnerable groups in the UK Methods This project involved the development and use of the method of Critical Interpretive Synthesis (CIS). This approach is sensitised to the processes of conventional systematic review methodology and draws on recent advances in methods for interpretive synthesis. Results Many analyses of equity of access have rested on measures of utilisation of health services, but these are problematic both methodologically and conceptually. A more useful means of understanding access is offered by the synthetic construct of candidacy. Candidacy describes how people's eligibility for healthcare is determined between themselves and health services. It is a continually negotiated property of individuals, subject to multiple influences arising both from people and their social contexts and from macro-level influences on allocation of resources and configuration of services. Health services are continually constituting and seeking to define the appropriate objects of medical attention and intervention, while at the same time people are engaged in constituting and defining what they understand to be the appropriate objects of medical attention and intervention. Access represents a dynamic interplay between these simultaneous, iterative and mutually reinforcing processes. By attending to how vulnerabilities arise in relation to candidacy, the phenomenon of access can be better understood, and more appropriate recommendations made for policy, practice and future research. Discussion By innovating with existing methods for interpretive synthesis, it was possible to produce not only new methods for conducting what we have termed critical interpretive synthesis, but

  6. 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

  7. IL-1 is a critical regulator of group 2 innate lymphoid cell function and plasticity.

    PubMed

    Ohne, Yoichiro; Silver, Jonathan S; Thompson-Snipes, LuAnn; Collet, Magalie A; Blanck, Jean Philippe; Cantarel, Brandi L; Copenhaver, Alan M; Humbles, Alison A; Liu, Yong-Jun

    2016-06-01

    Group 2 innate lymphoid cells (ILC2 cells) are important for type 2 immune responses and are activated by the epithelial cytokines interleukin 33 (IL-33), IL-25 and thymic stromal lymphopoietin (TSLP). Here we demonstrated that IL-1β was a critical activator of ILC2 cells, inducing proliferation and cytokine production and regulating the expression of epithelial cytokine receptors. IL-1β also governed ILC2 plasticity by inducing low expression of the transcription factor T-bet and the cytokine receptor chain IL-12Rβ2, which enabled the conversion of these cells into an ILC1 phenotype in response to IL-12. This transition was marked by an atypical chromatin landscape characterized by the simultaneous transcriptional accessibility of the locus encoding interferon-γ (IFN-γ) and the loci encoding IL-5 and IL-13. Finally, IL-1β potentiated ILC2 activation and plasticity in vivo, and IL-12 acted as the switch that determined an ILC2-versus-ILC1 response. Thus, we have identified a previously unknown role for IL-1β in facilitating ILC2 maturation and plasticity. PMID:27111142

  8. 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.

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

    SciTech Connect

    Manabe, K.; Endo, Akira; Eckerman, Keith 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.

  10. 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.

  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. 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. PMID:27451427

  13. 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. PMID:25816278

  14. 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.

  15. 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.

  16. Dose conversion coefficients for ICRP110 voxel phantom in the Geant4 Monte Carlo code

    NASA Astrophysics Data System (ADS)

    Martins, M. C.; Cordeiro, T. P. V.; Silva, A. X.; Souza-Santos, D.; Queiroz-Filho, P. P.; Hunt, J. G.

    2014-02-01

    The reference adult male voxel phantom recommended by International Commission on Radiological Protection no. 110 was implemented in the Geant4 Monte Carlo code. Geant4 was used to calculate Dose Conversion Coefficients (DCCs) expressed as dose deposited in organs per air kerma for photons, electrons and neutrons in the Annals of the ICRP. In this work the AP and PA irradiation geometries of the ICRP male phantom were simulated for the purpose of benchmarking the Geant4 code. Monoenergetic photons were simulated between 15 keV and 10 MeV and the results were compared with ICRP 110, the VMC Monte Carlo code and the literature data available, presenting a good agreement.

  17. The need for changes in ICRP policy: some examples based on the Chernobyl experience in Ukraine.

    PubMed

    Likhtarov, Illya A; Kovgan, Leonila N

    2002-06-01

    Current ICRP policy in radiological protection (ICRP Publication 60) is based on the independent restriction of exposure and sources for practice and intervention. Such subdivision of exposure and sources leads to a number of problems and contradictions in different applications. In a recent memorandum of the ICRP, published in the Journal of Radiological Protection in 2001, and ICRP Publications 81 and 82, the directions for settling some of these problems are indicated. This paper shows that in Ukraine, after the Chernobyl accident, a number of problems and contradictions occurred as the result of strictly separated limitation of the sources and exposure. These are demonstrated through four 'radiological paradoxes': (1) resettlement of inhabitants from territories radioactively contaminated after the Chernobyl accident to 'clean' ones, but with anomalous high levels of radon exposure in houses; (2) necessity of summation of the Chernobyl accidental doses and doses caused by normally operating nuclear power plant (NPP) to meet the requirements of Ukrainian law, which is based on the principle of 'social equity' of different sources of exposure; (3) the necessity to answer the question of primary importance: when will the Chernobyl accident finally end and when can exposure from contaminated territories be considered as exposure from old contamination? (4) the start of decommissioning of the Chernobyl NPP and transformation of the 'Object Shelter' (located inside the exclusion zone) are now slowed down because of the absence of a definite ideology for dose limitation of workers involved, who are exposed to several types of source simultaneously. The authors believe that the concept of controllable dose as presented by Professor Roger H Clarke on behalf of the ICRP can resolve such paradoxes. The changes to ICRP policy need to be made carefully in order to provide an orderly transition.

  18. A pilot exploration of the use of compassionate images in a group of self-critical people.

    PubMed

    Gilbert, Paul; Irons, Chris

    2004-07-01

    Self-criticism has long been associated with a variety of psychological problems and is often a key focus for intervention in psychotherapy. Recent work has suggested that self-critics have underelaborated and underdeveloped capacities for compassionate self-soothing and warmth. This pilot study developed a diary for monitoring self-attacking and self-soothing thoughts and images. It also explored the personal experiences of a group of volunteer self-critics from the local depression support group who were given training in self-soothing and self-compassion. Although using small numbers, this study suggests the potential value of developing more complex methodologies for studying the capacity for self-compassion, interventions to increase self-compassion (including imagery techniques), and their effects on mental health. PMID:15487546

  19. A pilot exploration of the use of compassionate images in a group of self-critical people.

    PubMed

    Gilbert, Paul; Irons, Chris

    2004-07-01

    Self-criticism has long been associated with a variety of psychological problems and is often a key focus for intervention in psychotherapy. Recent work has suggested that self-critics have underelaborated and underdeveloped capacities for compassionate self-soothing and warmth. This pilot study developed a diary for monitoring self-attacking and self-soothing thoughts and images. It also explored the personal experiences of a group of volunteer self-critics from the local depression support group who were given training in self-soothing and self-compassion. Although using small numbers, this study suggests the potential value of developing more complex methodologies for studying the capacity for self-compassion, interventions to increase self-compassion (including imagery techniques), and their effects on mental health.

  20. 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)

  1. 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…

  2. [A Critical Condition of Clinical Studies in Japan -- A Battle of Clinical Study Groups].

    PubMed

    Furukawa, Hiroshi

    2016-04-01

    The post-marketing clinical study groups have been losing their activity due to stop of financial support. As the result, clinical study groups cannot achieve any EBM for treatment guidelines. Financial supports should be restarted immediately not to extinguish the post-marketing clinical studies and study groups. PMID:27220798

  3. 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…

  4. 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…

  5. Significant impact on effective doses received during commercial flights calculated using the new ICRP radiation weighting factors.

    PubMed

    Chen, Jing; Mares, Vladimir

    2010-01-01

    This note discusses the significant impact on effective doses received during commercial flights calculated using the new International Commission on Radiological Protection (ICRP) radiation weighting factors. It also provides an update on adult effective doses given in a previous article in Health Physics when the old ICRP radiation weighting factors were used.

  6. Significant impact on effective doses received during commercial flights calculated using the new ICRP radiation weighting factors.

    PubMed

    Chen, Jing; Mares, Vladimir

    2010-01-01

    This note discusses the significant impact on effective doses received during commercial flights calculated using the new International Commission on Radiological Protection (ICRP) radiation weighting factors. It also provides an update on adult effective doses given in a previous article in Health Physics when the old ICRP radiation weighting factors were used. PMID:19959953

  7. Renormalization group calculation of the universal critical exponents of a polymer molecule

    NASA Astrophysics Data System (ADS)

    Belohorec, Peter

    In this work the excluded volume problem of a linear flexible polymer molecule in a solution was investigated using a new method. The Domb-Joyce (DJ) lattice model (Domb C. and Joyce G. S. (1972). J. Phys. C: Solid State Phys. 5 956) was used to describe the polymer chain with a varying excluded volume parameterramateur w and bond number N. Monte Carlo (MC) generated data for the mean square end-to-end distance Rsbsp{N}{2} and the second virial coefficient Asb{2,N} were analyzed by a renormalization group technique that is a generalization of the one-parameter recursion model (Nickel B. G. (1991). Macromolecules 24, 1358). By defining the effective exponents nusb{R}(N,psi) and nusb{A}(N,psi ) using 2sp{2nusb{R}} = Rsbsp{2N}{2}/Rsbsp{N}{2} and 2sp{3nusb{A}} = Asb{2,2N}/Asb{2,N} where psi = {1/4}({6/pi})sp{3/2}{{Asb{2,N}}/{Rsbsp{N}{3}}} is the interpenetration function, the corrections varying as Nsp{-Delta} were eliminated from nusb{R}(N,psi) and nusb{A}(N,psi) and both universal critical exponents nu and Delta of the expected long chain behaviors Rsbsp{N}{2}~ asb{R}Nsp{2nu}(1 + bsb{R}Nsp{-Delta} +\\...) and Asb{2,N}~ asb{A}Nsp{3nu}(1 + bsb{A}Nsp{-Delta} +\\...) were determined very accurately. The problems encountered by standard methods when extracting the values of the leading exponent nu and the correction to scaling exponent Delta from the finite chain data were eliminated by the simultaneous use of many models (i.e., w in the range of 0 < omega ≤ 1) and by the use of the effective exponent transformation. Other universal quantities such as the asymptotic value psi* of the interpenetration function proportional to the dimensionless ratio of leading scaling amplitudes asb{A}/asbsp{R}{3/2} as well as the ratio of correction to scaling amplitudes bsb{A}/bsb{R} were also calculated with a very good precision. The results are nu = 0.58756(5),\\ Delta = 0.5310(33), psi* = 0.23221(11) and bsb{A}/bsb{R} = -.0.9028(132). The numerical solution of the DJ model

  8. 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…

  9. 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…

  10. 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,…

  11. Using Code-Recode to Detect Critical Thinking Aspects of Asynchronous Small Group CMC Collaborative Learning

    ERIC Educational Resources Information Center

    Oriogun, Peter K.; Cave, Diana

    2008-01-01

    This article empirically validates an existing content analysis scheme and addresses a main concern of researchers about text-based, online transcripts in the form of code-recoding by mapping our scheme to the practical inquiry, cognitive presence model's five phases directly to realise higher-order thinking or critical thinking aspects for our…

  12. 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)

  13. 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…

  14. 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.

  15. Applicability of dose conversion coefficients of ICRP 74 to Asian adult males: Monte Carlo simulation study.

    PubMed

    Lee, Choonsik; Lee, Choonik; Lee, Jai-Ki

    2007-05-01

    International Commission on Radiological Protection (ICRP) reported comprehensive dose conversion coefficients for adult population, which is exposed to external photon sources in the Publication 74. However, those quantities were calculated from so-called stylized (or mathematical) phantoms composed of simplified mathematical surface equations so that the discrepancy between the phantoms and real human anatomy has been investigated by several authors using Caucasian-based voxel phantoms. To address anatomical and racial limitations of the stylized phantoms, several Asian-based voxel phantoms have been developed by Korean and Japanese investigators, independently. In the current study, photon dose conversion coefficients of ICRP 74 were compared with those from a total of five Asian-based male voxel phantoms, whose body dimensions were almost identical. Those of representative radio-sensitive organs (testes, red bone marrow, colon, lungs, and stomach), and effective dose conversion coefficients were obtained for comparison. Even though organ doses for testes, colon and lungs, and effective doses from ICRP 74 agreed well with those from Asian voxel phantoms within 10%, absorbed doses for red bone marrow and stomach showed significant discrepancies up to 30% which was mainly attributed to difference of phantom description between stylized and voxel phantoms. This study showed that the ICRP 74 dosimetry data, which have been reported to be unrealistic compared to those from Caucasian-based voxel phantoms, are also not appropriate for Asian population. PMID:17337194

  16. 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

  17. 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

  18. 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.

  19. 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.

  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 Critically Conscious Approach to Fostering the Success of College Students from Underrepresented Groups

    ERIC Educational Resources Information Center

    Seider, Scott C.; Clark, Shelby; Soutter, Madora

    2015-01-01

    Over the past decade, many student affairs professionals have turned their attention to non-cognitive factors that can play a role in supporting students from underrepresented groups in making it to and through college. The work in this area that has gotten the most attention in recent years has focused on students' sense of belonging and…

  2. 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…

  3. 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...

  4. 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

    2014-04-01

    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.

  5. 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

  6. Critical catalytic functional groups in the mechanism of aspartate-beta-semialdehyde dehydrogenase.

    PubMed

    Blanco, Julio; Moore, Roger A; Faehnle, Christopher R; Viola, Ronald E

    2004-10-01

    Aspartate-beta-semialdehyde dehydrogenase (ASADH) catalyzes the reductive dephosphorylation of beta-aspartyl phosphate to L-aspartate-beta-semialdehyde in the aspartate biosynthetic pathway. This pathway is not found in humans or other eukaryotic organisms, yet is required for the production of threonine, isoleucine, methionine and lysine in most microorganisms. The mechanism of this enzyme has been examined through the structures of two active-site mutants of ASADH from Haemophilus influenzae. Replacement of the enzyme active-site cysteine with serine (C136S) leads to a dramatic loss of catalytic activity caused by the expected decrease in nucleophilicity, but also by a change in the orientation of the serine hydroxyl group relative to the cysteine thiolate. In contrast, in the H277N active-site mutant the introduced amide is oriented in virtually the same position as that of the histidine imidazole ring. However, a shift in the position of the bound reaction intermediate to accommodate this shorter asparagine side chain, coupled with the inability of this introduced amide to serve as a proton acceptor, results in a 100-fold decrease in the catalytic efficiency of H277N relative to the native enzyme. These mutant enzymes have the same overall fold and high structural identity to native ASADH. However, small perturbations in the positioning of essential catalytic groups or reactive intermediates have dramatic effects on catalytic efficiency. PMID:15388927

  7. 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)

  8. Use of the extreme groups approach: a critical reexamination and new recommendations.

    PubMed

    Preacher, Kristopher J; Rucker, Derek D; MacCallum, Robert C; Nicewander, W Alan

    2005-06-01

    Analysis of continuous variables sometimes proceeds by selecting individuals on the basis of extreme scores of a sample distribution and submitting only those extreme scores to further analysis. This sampling method is known as the extreme groups approach (EGA). EGA is often used to achieve greater statistical power in subsequent hypothesis tests. However, there are several largely unrecognized costs associated with EGA that must be considered. The authors illustrate the effects EGA can have on power, standardized effect size, reliability, model specification, and the interpretability of results. Finally, the authors discuss alternative procedures, as well as possible legitimate uses of EGA. The authors urge researchers, editors, reviewers, and consumers to carefully assess the extent to which EGA is an appropriate tool in their own research and in that of others.

  9. A Monte Carlo calibration of a whole body counter using the ICRP computational phantoms.

    PubMed

    Nilsson, Jenny; Isaksson, Mats

    2015-03-01

    A fast and versatile calibration of a whole body counter (WBC) is presented. The WBC, consisting of four large plastic scintillators, is to be used for measurements after accident or other incident involving ionising radiation. The WBC was calibrated using Monte Carlo modelling and the ICRP computational phantoms. The Monte Carlo model of the WBC was made in GATE, v6.2 (Geant4 Application for Tomographic Emission) and MATLAB. The Monte Carlo model was verified by comparing simulated energy spectrum and simulated counting efficiency with experimental energy spectrum and experimental counting efficiency for high-energy monoenergetic gamma-emitting point sources. The simulated results were in good agreement with experimental results except when compared with experimental results from high dead-time (DT) measurements. The Monte Carlo calibration was made for a heterogeneous source distribution of (137)Cs and (40)K, respectively, inside the ICRP computational phantoms. The source distribution was based on the biokinetic model for (137)Cs.

  10. Influences of parameter uncertainties within the ICRP-66 respiratory tract model: a parameter sensitivity analysis.

    PubMed

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

    2003-11-01

    An important aspect in model uncertainty analysis is the evaluation of input parameter sensitivities with respect to model outcomes. In previous publications, parameter uncertainties were examined for the ICRP-66 respiratory tract model. The studies were aided by the development and use of a computer code LUDUC (Lung Dose Uncertainty Code) which allows probabilities density functions to be specified for all ICRP-66 model input parameters. These density functions are sampled using Latin hypercube techniques with values subsequently propagated through the ICRP-66 model. In the present study, LUDUC has been used to perform a detailed parameter sensitivity analysis of the ICRP-66 model using input parameter density functions specified in previously published articles. The results suggest that most of the variability in the dose to a given target region is explained by only a few input parameters. For example, for particle diameters between 0.1 and 50 microm, about 50% of the variability in the total lung dose (weighted sum of target tissue doses) for 239PuO2 is due to variability in the dose to the alveolar-interstitial (AI) region. In turn, almost 90% of the variability in the dose to the AI region is attributable to uncertainties in only four parameters in the model: the ventilation rate, the AI deposition fraction, the clearance rate constant for slow-phase absorption of deposited material to the blood, and the clearance rate constant for particle transport from the AI2 to bb1 compartment. A general conclusion is that many input parameters do not significantly influence variability in final doses. As a result, future research can focus on improving density functions for those input variables that contribute the most to variability in final dose values. PMID:14571988

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

    PubMed

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

    2012-07-21

    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.

  12. The reported views and experiences of cancer service users from minority ethnic groups: a critical review of the literature.

    PubMed

    Elkan, R; Avis, M; Cox, K; Wilson, E; Patel, S; Miller, S; Deepak, N; Edwards, C; Staniszewska, S; Kai, J

    2007-03-01

    There is growing evidence of inequalities in access to high-quality cancer services between minority and majority ethnic groups. However, little research has been carried out from the perspective of users from minority ethnic groups themselves. This paper reports a review of the British literature exploring the views and experiences of cancer service users from minority ethnic groups. We reviewed 25 qualitative studies that reported the experiences of people from minority ethnic groups. The studies highlighted significant issues and challenges, including comprehension and communication barriers, a lack of awareness of the existence of services and a perceived failure by providers to accommodate religious and cultural diversity. This paper critically discusses some of the explanations commonly invoked for ethnic inequalities in access to high-quality care, such as the belief that the lack of use of services reflects a lack of need. Despite positive initiatives to respond better to the needs of minority groups, we suggest the impact of these remains highly variable. Institutional racism within services is still much in evidence.

  13. 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.

  14. CSRL-V: an ENDF/B-V 227-group cross section library for criticality safety studies

    SciTech Connect

    Ford, III, W. E.; Westfall, R. M.; Diggs, B. R.; Webster, C. C.; Knight, J. R.

    1980-01-01

    The AMPX system was used to generate a P/sub 3/ 227-neutron-group master cross-section library containing data for all materials in the ENDF/B-V general purpose file. CSRL-V is a data base for the subsequent generation of problem-dependent fine- and/or broad-group cross sections for shipping cask calculations and other criticality safety analyses. The problem-dependent data can be used with codes such as KENO IV, ANISN, XSDRNPM, VENTURE, DOT, MORSE, etc. CSRL-V data can be coupled with photon-production and photon-interaction multigroup data produced with the AMPX system to produce coupled neutron-gamma cross-section libraries. Consideration was given to the resonance structure of prominent nuclei, the thresholds of important reactions, and various fission spectra. Data in the CSRL-V library were checked for first-order consistencies and tested in performance parameter calculations for a series of benchmark critical experiments. The CSRL-V library is available on magnetic tape. 1 table. (RWR)

  15. 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

  16. Evolutionary conservation of a functionally important backbone phosphate group critical for aminoacylation of histidine tRNAs.

    PubMed

    Rosen, Abbey E; Brooks, Bonnie S; Guth, Ethan; Francklyn, Christopher S; Musier-Forsyth, Karin

    2006-07-01

    All histidine tRNA molecules have an extra nucleotide, G-1, at the 5' end of the acceptor stem. In bacteria, archaea, and eukaryotic organelles, G-1 base pairs with C73, while in eukaryotic cytoplasmic tRNAHis, G-1 is opposite A73. Previous studies of Escherichia coli histidyl-tRNA synthetase (HisRS) have demonstrated the importance of the G-1:C73 base pair to tRNAHis identity. Specifically, the 5'-monophosphate of G-1 and the major groove amine of C73 are recognized by E. coli HisRS; these individual atomic groups each contribute approximately 4 kcal/mol to transition state stabilization. In this study, two chemically synthesized 24-nucleotide RNA microhelices, each of which recapitulates the acceptor stem of either E. coli or Saccharomyces cervisiae tRNAHis, were used to facilitate an atomic group "mutagenesis" study of the -1:73 base pair recognition by S. cerevisiae HisRS. Compared with E. coli HisRS, microhelixHis is a much poorer substrate relative to full-length tRNAHis for the yeast enzyme. However, the data presented here suggest that, similar to the E. coli system, the 5' monophosphate of yeast tRNA(His) is critical for aminoacylation by yeast HisRS and contributes approximately 3 kcal/mol to transition state stability. The primary role of the unique -1:73 base pair of yeast tRNAHis appears to be to properly position the critical 5' monophosphate for interaction with the yeast enzyme. Our data also suggest that the eukaryotic HisRS/tRNAHis interaction has coevolved to rely less on specific major groove interactions with base atomic groups than the bacterial system. PMID:16741232

  17. 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

  18. 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

  19. 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

  20. Estimate of the critical exponents from the field-theoretical renormalization group: mathematical meaning of the 'Standard Values'

    SciTech Connect

    Pogorelov, A. A.; Suslov, I. M.

    2008-06-15

    New estimates of the critical exponents have been obtained from the field-theoretical renormalization group using a new method for summing divergent series. The results almost coincide with the central values obtained by Le Guillou and Zinn-Justin (the so-called standard values), but have lower uncertainty. It has been shown that usual field-theoretical estimates implicitly imply the smoothness of the coefficient functions. The last assumption is open for discussion in view of the existence of the oscillating contribution to the coefficient functions. The appropriate interpretation of the last contribution is necessary both for the estimation of the systematic errors of the standard values and for a further increase in accuracy.

  1. 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.

  2. 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

  3. Comparison of old and new ICRP models for respiratory tract dosimetry

    SciTech Connect

    Boecker, B.B.

    1993-12-31

    This paper examines the historical development and application of respiratory tract dosimetry models by the International Commission for Radiological Protection, ICRP, for health protection from inhaled radioactive aerosols. Three different models are discussed, those that were included in ICRP recommendations published in 1960 and 1979, and the new ICRP Publication 66. Basic features of these models are compared and contrasted. These features include model structure, sites and frequencies of particle deposition, processes and rates of clearance of the deposited material from the respiratory tract, and consideration of the parameters involved in these processes and how various factors can influence these parameters. All three models lead to the calculation of absorbed radiation doses with differing degrees of regional and local specificity. These calculations are achieved using different tools ranging from quick hand calculations to sophisticated computerized modeling approaches. A side-by-side review of these models indicates several important trends in respiratory tract dosimetry models, the most obvious of which is the increased complexity of each new model over the past 30+ years. These increases reflect both the increasing size of the knowledge base derived from studies in laboratory animals and in human subjects and the need for models more broadly applicable for both occupational and environmental exposures. It is likely that future research will be directed to those key aspects of the new model having the largest uncertainties. The detailed design of the new model and its associated software provide excellent means of identifying useful research areas and using the resulting new information in organized and productive ways.

  4. 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. PMID:21147784

  5. Evaluation of effective dose conversion coefficients for Korean adults during medical x-ray examinations up to 150 keV through comparison with ICRP Publication 74 and ICRP Publication 116.

    PubMed

    Keum, Mihyun; Park, Jae Hong; Park, Sung Ho; Ahn, Seung Do

    2014-03-01

    A Monte Carlo program for calculating organ doses for patients undergoing medical x-ray examination (PCXMC) was used to calculate effective dose conversion coefficients for Korean adults. Two sets of effective dose results were calculated based on tissue weighting factors recommended in International Commission on Radiological Protection (ICRP) Publications 60 and 103 for monochromatic energy photons of 10, 15, 20, 30, 40, 50, 60, 70, 80, 100 and 150 keV. The results were obtained for monoenergetic photons, since effective dose conversion coefficients recommended in ICRP Publications 74 and 116 were given for monochromatic energies, thereby enabling the comparison of our result to those suggested by the ICRP publications. The areas of comparison include: to observe effects due to changes in tissue weighting factors, modification within Medical Internal Radiation Dose (MIRD) phantoms and differences in phantom types. The phantom employed in the PCXMC program is a modified version of the phantom used in ICRP Publication 74, with additional organs that were added in order to take into account the updated tissue weighting factors given in ICRP Publication 103. Both use MIRD phantoms but our study modified the phantom size to the average physical condition of Korean adults, while ICRP Publication 74 uses the phantom size of the reference man defined in ICRP Publication 23. On the other hand, the effective dose suggested in ICRP 116 was calculated using an entirely different type of phantom: a voxel phantom with the size of reference man. Although significant differences were observed for certain organ doses in the lateral beam directions, differences in the effective doses were within 5% for the anterior-posterior (AP) and posterior-anterior (PA) directions, and within 16% in lateral directions when tissue weighting factors were applied and the variations were adjusted for all three comparisons. The results show that calculation of effective doses for Korean adults

  6. 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.

  7. 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.

  8. 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

  9. [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.

  10. 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. PMID:27285880

  11. 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.

  12. Magnetic transition from the paramagnetic to long-period structure in RMn2O5 multiferroics: Renormalization group analysis of critical behavior

    NASA Astrophysics Data System (ADS)

    Men'shenin, V. V.

    2013-06-01

    A transition from the paramagnetic state to a long-period magnetic structure with an incommensurate wave vector along one crystallographic axis in RMn2O5 multiferroics is considered. An effective Hamiltonian for these oxides is constructed with allowance for spin fluctuations. Critical points are found, and their stability is analyzed using the renormalization group approach. It is shown that critical fluctuations in these compounds admit a second-order phase transition with respect to a multicomponent order parameter.

  13. Analysis of core-periphery organization in protein contact networks reveals groups of structurally and functionally critical residues.

    PubMed

    Isaac, Arnold Emerson; Sinha, Sitabhra

    2015-10-01

    The representation of proteins as networks of interacting amino acids, referred to as protein contact networks (PCN), and their subsequent analyses using graph theoretic tools, can provide novel insights into the key functional roles of specific groups of residues. We have characterized the networks corresponding to the native states of 66 proteins (belonging to different families) in terms of their core-periphery organization. The resulting hierarchical classification of the amino acid constituents of a protein arranges the residues into successive layers - having higher core order - with increasing connection density, ranging from a sparsely linked periphery to a densely intra-connected core (distinct from the earlier concept of protein core defined in terms of the three-dimensional geometry of the native state, which has least solvent accessibility). Our results show that residues in the inner cores are more conserved than those at the periphery. Underlining the functional importance of the network core, we see that the receptor sites for known ligand molecules of most proteins occur in the innermost core. Furthermore, the association of residues with structural pockets and cavities in binding or active sites increases with the core order. From mutation sensitivity analysis, we show that the probability of deleterious or intolerant mutations also increases with the core order. We also show that stabilization centre residues are in the innermost cores, suggesting that the network core is critically important in maintaining the structural stability of the protein. A publicly available Web resource for performing core-periphery analysis of any protein whose native state is known has been made available by us at http://www.imsc.res.in/ ~sitabhra/proteinKcore/index.html.

  14. 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…

  15. Influences of parameter uncertainties within the ICRP 66 respiratory tract model: particle deposition.

    PubMed

    Bolch, W E; Farfán, E B; Huh, C; Huston, T E; Bolch, W E

    2001-10-01

    Risk assessment associated with the inhalation of radioactive aerosols requires as an initial step the determination of particle deposition within the various anatomic regions of the respiratory tract. The model outlined in ICRP Publication 66 represents to date one of the most complete overall descriptions of not only particle deposition, but of particle clearance and local radiation dosimetry of lung tissues. In this study, a systematic review of the deposition component within the ICRP 66 respiratory tract model was conducted in which probability density functions were assigned to all input parameters. 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 of the model parameters needed to assess particle deposition within the extrathoracic (anterior and posterior), bronchial, bronchiolar, and alveolar-interstitial regions of the ICRP 66 respiratory tract model. Particle deposition values for the various trial simulations were shown to be well described by lognormal probability distributions. Geometric mean deposition fractions from LUDUC were found to be within approximately +/- 10% of the single-value estimates from the LUDEP computer code for each anatomic region and for particle diameters ranging from 0.001 to 50 microm. In all regions of the respiratory tract, LUDUC simulations for an adult male at light exertion show that uncertainties in particle deposition fractions are distributed only over a range of about a factor of approximately 2-4 for particle sizes between 0.005 to 0.2 microm. Below 0.005 microm, uncertainties increase only for deposition within the alveolar region. At particle sizes exceeding 1 microm, uncertainties in the deposition fraction within the extrathoracic regions are relatively small, but approach a factor of 20 for deposition in the bronchial

  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. A modified ICRP 66 iodine gas uptake model and its parametric uncertainty.

    PubMed

    Harvey, R P; Hamby, D M; Palmer, T S

    2004-11-01

    Intakes via inhalation may occur from radionuclides released in the form of a gas. The chemical characteristics pertaining to the release influence the intake and subsequent dose to an exposed individual. Gases are taken up or absorbed in the entire respiratory tract and the associated uptake mechanisms are quite different from deposition of particulates. Gaseous iodine can exist in various chemical forms, e.g., elemental iodine, inorganic, and organic iodine compounds. These different chemical species play an integral role in the gaseous uptake o f iodine in t he respiratory tract. Gas uptake in the various regions of the respiratory tract results in the intake of iodinated material into the body. The radioactive iodine taken up in the gas-exchange tissues is absorbed into the bloodstream of an individual and subsequently transferred to other organs. Iodine in the circulatory system can then be taken up by the thyroid gland, with resulting dose to the thyroid. The magnitude and uncertainty in regional gas uptake is important in the assessment of individuals exposed to airborne releases of radioiodine. The current ICRP 66 model is rudimentary and estimates regional gas uptake based on solubility and reactivity of the different radionuclides entering the respiratory tract. The modified model proposed here employs methodology and a mathematical structure to determine estimates of fractional gas uptake rather than defaulting to literature values, as in the current ICRP model. Model parameters have been assigned input distributions and estimates of uncertainty have been determined. A sensitivity analysis of these parameters has been performed to demonstrate the importance of each of these parameters. The sensitivity analysis ranks the model-input parameters by their importance to estimates of regional gas uptake. The model developed herein may be used for improved estimation of gas uptake in the respiratory tract and subsequent dose estimates from the different

  18. Fermionic quantum criticality in honeycomb and π -flux Hubbard models: Finite-size scaling of renormalization-group-invariant observables from quantum Monte Carlo

    NASA Astrophysics Data System (ADS)

    Parisen Toldin, Francesco; Hohenadler, Martin; Assaad, Fakher F.; Herbut, Igor F.

    2015-04-01

    We numerically investigate the critical behavior of the Hubbard model on the honeycomb and the π -flux lattice, which exhibits a direct transition from a Dirac semimetal to an antiferromagnetically ordered Mott insulator. We use projective auxiliary-field quantum Monte Carlo simulations and a careful finite-size scaling analysis that exploits approximately improved renormalization-group-invariant observables. This approach, which is successfully verified for the three-dimensional XY transition of the Kane-Mele-Hubbard model, allows us to extract estimates for the critical couplings and the critical exponents. The results confirm that the critical behavior for the semimetal to Mott insulator transition in the Hubbard model belongs to the Gross-Neveu-Heisenberg universality class on both lattices.

  19. 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…

  20. 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.

  1. 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.

  2. [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.

  3. Entrustable professional activities and curricular milestones for fellowship training in pulmonary and critical care medicine: executive summary from the Multi-Society Working Group.

    PubMed

    Fessler, Henry E; Addrizzo-Harris, Doreen; Beck, James M; Buckley, John D; Pastores, Stephen M; Piquette, Craig A; Rowley, James A; Spevetz, Antoinette

    2014-10-01

    Assessment of graduate medical trainee progress via the accomplishment of competency milestones is an important element of the Next Accreditation System of the Accreditation Council for Graduate Medical Education. This article summarizes the findings of a multisociety working group that was tasked with creating the entrustable professional activities and curricular milestones for fellowship training in pulmonary medicine, critical care medicine, and combined programs. Using the Delphi process, experienced medical educators from the American College of Chest Physicians, American Thoracic Society, Society of Critical Care Medicine, and Association of Pulmonary and Critical Care Medicine Program Directors reached consensus on the detailed curricular content and expected skill set of graduates of these programs. These are now available to trainees and program directors for the purposes of curriculum design, review, and trainee assessment. PMID:25226119

  4. Dosimetry of metal tritide particles as evaluated by the ICRP 66 model and a biokinetic model from laboratory rats.

    PubMed

    Zhou, Y; Cheng, Y S

    2004-02-01

    Internal radiation from inhalation of metal tritide aerosols may present a significant radiation protection problem for nuclear facility workers. Dose was evaluated for three metal tritides: hafnium, titanium, and zirconium. The study included in vitro and in vivo exposures. The inhalation doses for the three materials were calculated by using the ICRP 66 lung model. The doses also were evaluated by a biokinetic model, which was developed according to the results of animal studies. Results showed that the hafnium tritide particles were the most dense but they had a lower dissolution rate and a higher retention rate. Among these three tritides, hafnium was classified as a Type S material according to the ICRP 66 publication, whereas titanium and zirconium ranked between Type M and F materials. The dissolution rate of hafnium tritide appeared to agree well with the in vitro and in vivo studies. The dissolution rates of the other two materials in the in vitro studies were a little higher than those of the in vivo studies. The doses calculated by the ICRP 66 model for all materials were approximately two orders smaller than the doses obtained by the animal studies. This bias was caused by the different intake methods of the ICRP 66 model (inhalation) and in the animal study (instillation). The doses were on the same order while correcting for deposition fractions. The effective doses for hafnium, titanium, and zirconium tritides were 5.43 x 10(-10), 9.05 x 10(-11), and 6.5 x 10(-10) Sv Bq(-1), respectively, according to the animal studies. PMID:14744049

  5. 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.

  6. Calculated organ doses for Mayak production association central hall using ICRP and MCNP.

    PubMed

    Choe, Dong-Ok; Shelkey, Brenda N; Wilde, Justin L; Walk, Heidi A; Slaughter, David M

    2003-03-01

    As part of an ongoing dose reconstruction project, equivalent organ dose rates from photons and neutrons were estimated using the energy spectra measured in the central hall above the graphite reactor core located in the Russian Mayak Production Association facility. Reconstruction of the work environment was necessary due to the lack of personal dosimeter data for neutrons in the time period prior to 1987. A typical worker scenario for the central hall was developed for the Monte Carlo Neutron Photon-4B (MCNP) code. The resultant equivalent dose rates for neutrons and photons were compared with the equivalent dose rates derived from calculations using the conversion coefficients in the International Commission on Radiological Protection Publications 51 and 74 in order to validate the model scenario for this Russian facility. The MCNP results were in good agreement with the results of the ICRP publications indicating the modeling scenario was consistent with actual work conditions given the spectra provided. The MCNP code will allow for additional orientations to accurately reflect source locations.

  7. Implications in medical imaging of the new ICRP thresholds for tissue reactions.

    PubMed

    Vañó, E; Miller, D L; Dauer, L

    2015-06-01

    The International Commission on Radiological Protection (ICRP) statement on tissue reactions, issued by the Commission in April 2011, reviewed epidemiological evidence and suggested that there are some tissue reactions where threshold doses are or may be lower than those previously considered. For the lens of the eye, the threshold is now considered to be 0.5 Gy. The absorbed dose threshold for circulatory disease in the heart and brain may be as low as 0.5 Gy. These values can be reached in some patients during interventional cardiology or neuroradiology procedures. They may also be of concern for repeated computed tomography examinations of the head. The new thresholds should be considered in optimisation strategies for clinical procedures, especially in patients likely to require repeated interventions. The new dose thresholds also affect occupational protection for operators and staff. Some operators do not protect their eyes or their brain adequately. After several years of work without proper protection, the absorbed doses to the lens of the eye and the brain of staff can exceed 0.5 Gy. More research is needed to understand the biological effects of cumulative incident air kerma and the instantaneous air kerma rates currently used in medical imaging. The new thresholds, and the need for specific occupational dosimetry related to lens doses, should be considered in radiation protection programmes, and should be included in the education and training of professionals involved in fluoroscopy guided procedures and computed tomography. PMID:25816265

  8. 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. PMID:14526971

  9. Calculated organ doses for Mayak production association central hall using ICRP and MCNP.

    PubMed

    Choe, Dong-Ok; Shelkey, Brenda N; Wilde, Justin L; Walk, Heidi A; Slaughter, David M

    2003-03-01

    As part of an ongoing dose reconstruction project, equivalent organ dose rates from photons and neutrons were estimated using the energy spectra measured in the central hall above the graphite reactor core located in the Russian Mayak Production Association facility. Reconstruction of the work environment was necessary due to the lack of personal dosimeter data for neutrons in the time period prior to 1987. A typical worker scenario for the central hall was developed for the Monte Carlo Neutron Photon-4B (MCNP) code. The resultant equivalent dose rates for neutrons and photons were compared with the equivalent dose rates derived from calculations using the conversion coefficients in the International Commission on Radiological Protection Publications 51 and 74 in order to validate the model scenario for this Russian facility. The MCNP results were in good agreement with the results of the ICRP publications indicating the modeling scenario was consistent with actual work conditions given the spectra provided. The MCNP code will allow for additional orientations to accurately reflect source locations. PMID:12645766

  10. 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.

  11. 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.

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

    NASA Astrophysics Data System (ADS)

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

    2009-11-01

    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.

  13. 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

    2009-11-01

    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. PMID:19841518

  14. Table of DOE-STD-1027-92 Hazard Category 3 threshold quantities for the ICRP-30 list of 757 radionuclides: LANL fact sheet

    SciTech Connect

    Clow, J.; Elder, J.; Heindel, G.; Inkret, W.; Miller, G.

    1995-08-01

    A table of DOE-STD-1027-92 Hazard Category 3 threshold quantities, in units of curies and grams, is presented for the International Commission on Radiological Protection-30 (ICRP-30) list of 757 radionuclides. The specific activity (Ci/gm) used to convert the threshold quantities from curies to grams is also calculated and tabulated. The half-life values used to generate the specific activities are those specified in ICRP-30.

  15. Organising Staff to Provide Individual Teaching in a Group: A Critical Review of Room Management and Related Procedures.

    ERIC Educational Resources Information Center

    Sturmey, P.; Crisp, A. G.

    1989-01-01

    The review of the literature on the use of room management (RM) procedures with severely disabled students concluded that RM may be an effective strategy for delivering individual instruction while maintaining high levels of group engagement in other students. RM can reduce problem behaviors and be maintained through positive monitoring and…

  16. Speech Criticism, Group Presentations, and Centrality: A Marriage Made in Heaven for the Basic Public Speaking Course.

    ERIC Educational Resources Information Center

    Ayres, Joe; Sonandre, Debbie Ayres

    This paper presents an exercise which serves as an addition to public speaking courses. Showing students how to uncover the speech patterns that shape their lives allows them to appreciate the importance of speech communication in their lives. In the exercise, groups analyze speeches and report their findings to the class. The exercise improves…

  17. 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…

  18. Measuring quality of sedation in adult mechanically ventilated critically ill patients. the Vancouver Interaction and Calmness Scale. Sedation Focus Group.

    PubMed

    de Lemos, J; Tweeddale, M; Chittock, D

    2000-09-01

    There are no reliable, valid, and responsive scales to measure the quality of sedation in adult critically ill patients. Our objective was to develop a summated rating scale with these properties and to define the minimal clinically important difference (MCID). We developed and tested the scale in an 18-bed medical-surgical intensive care unit (ICU) (12-bed acute and 6-bed subacute unit). Following identification of relevant domains and item derivation, 116 observations were made on 38 patients; psychometric properties and interrater reliability were assessed to allow item reduction. The final scale consisted of two five-item subscales quantifying calmness and interaction along a continuum from 5 to 30 points. Interrater reliability was 0.89 and 0.90; internal consistency was 0. 95 for both subscales. To test construct validity, MCID, and responsiveness 302 observations were made on 54 patients. Construct validity: calmness score vs. need for further intervention to make the patient calm (R = -0.82, P < 0.001); interaction score discriminated between acute vs. subacute units, mean scores 15.28 +/- 8.26 vs. 23.54 +/- 7.42, mean difference 8.27 (95% CI - 10.32 to -6.22); MCID - 2.2 and 2.5 for the calmness and interaction subscales; Guyatt's responsiveness statistics - 1.4 and 2.3. The Vancouver Interaction and Calmness Scale (VICS) is reliable, valid, and responsive.

  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. PMID

  20. 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.

  1. 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

  2. Body image and its relation to obesity for Pacific minority ethnic groups in New Zealand: a critical analysis.

    PubMed

    Teevale, Tasileta

    2011-03-01

    The stimulus behind most of the early investigations into Pacific or Polynesian peoples' body image, particularly those that looked to compare with Western or Westernised groups, is the assumption that Pacific peoples valued and therefore desired very large bodies, and in relation to obesity-risk, this is a problematic cultural feature to have. This may be driven by popular anecdotes which are captured in the title of one such study "Do Polynesians still believe that big is beautiful?" To the author's knowledge, no research in Pacific peoples' body image has been conducted in the New Zealand (NZ) context by Pacific researchers. This study makes a contribution to the literature gap and more importantly through an emic viewpoint. A critique of the current literature is provided below which calls into question the initial catalyst behind earlier investigations which have led to the perpetuation of particular types of body image research for Pacific groups. Using mixed-methods, the specific objective of this study was to describe the behaviours, beliefs and values of Pacific adolescents and their parents, that are related to body image. A self-completion questionnaire was administered to 2495 Pacific students who participated in the New Zealand arm of the Obesity Prevention In Communities (OPIC) project. Sixty-eight people (33 adolescents and 35 parents) from 30 Pacific households were interviewed in the qualitative phase of the study. This study found Pacific adolescents and their parents did not desire obesity-sized bodies but desired a range of average-sized bodies that met their Pacific-defined view of health. It is not clear whether body image research makes any meaningful contribution to obesity prevention for Pacific people, given the cultural-bounded nature of the concept "body image" which sits communication and understanding between obesity interventionists and all healthcare workers generally and Pacific communities. For obesity interventions to be

  3. 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

  4. 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

  5. The signature 3-O-sulfo group of the anticoagulant heparin sequence is critical for heparin binding to antithrombin but is not required for allosteric activation.

    PubMed

    Richard, Benjamin; Swanson, Richard; Olson, Steven T

    2009-10-01

    Heparin and heparan sulfate glycosaminoglycans allosterically activate the serpin, antithrombin, by binding through a specific pentasaccharide sequence containing a critical 3-O-sulfo group. To elucidate the role of the 3-O-sulfo group in the activation mechanism, we compared the effects of deleting the 3-O-sulfo group or mutating the Lys(114) binding partner of this group on antithrombin-pentasaccharide interactions by equilibrium binding and rapid kinetic analyses. Binding studies over a wide range of ionic strength and pH showed that loss of the 3-O-sulfo group caused a massive approximately 60% loss in binding energy for the antithrombin-pentasaccharide interaction due to the disruption of a cooperative network of ionic and nonionic interactions. Despite this affinity loss, the 3-O-desulfonated pentasaccharide retained the ability to induce tryptophan fluorescence changes and to enhance factor Xa reactivity in antithrombin, indicative of normal conformational activation. Rapid kinetic studies showed that loss of the 3-O-sulfo group affected both the ability of the pentasaccharide to recognize native antithrombin and its ability to preferentially bind and stabilize activated antithrombin. By contrast, mutation of Lys(114) solely affected the preferential interaction of the pentasaccharide with activated antithrombin. These findings demonstrate that the 3-O-sulfo group functions as a key determinant of heparin pentasaccharide activation of antithrombin both by contributing to the Lys(114)-independent recognition of native antithrombin and by triggering a Lys(114)-dependent induced fit interaction with activated antithrombin that locks the serpin in the activated state. PMID:19661062

  6. The self-defining critical group and its application to a measured check of the derived limit for [sup 125]I in drinking water

    SciTech Connect

    Bowlt, C.; Howe, J.R. )

    1992-12-01

    Using a series of daily measurements of [sup 125]I in the drinking water of North Surrey, England, from November 1988 through May 1990, the accumulated activities in the thyroids of adults drinking such water were calculated on the assumption that the fraction of ingested iodine taken up by the thyroid was f = 0.3 and the tap water consumption was C = 600 L y[sup [minus]1]. These figures were compared with measured values of [sup 125]I activities in 42 thyroids taken at necropsy from residents in the North Surrey area who were dying during this same time period. Eight thyroids (19%) had measured activities greater than predicted, so they were named the self-defining critical group. After comparing the thyroid with the drinking water activity, the current generalized derived limit for [sup 125]I in the drinking water may be too high by a factor of 2. The reason for this appears to be the use of f = 0.3 which is the mean value for the normal' population. Models involving critical groups should use values of parameters different from the mean. In the present case, making f = 0.6 would remove the discrepancy between measurement and prediction and would be in reasonable accord with measured distributions of f.

  7. Critical role of TLR2 and MyD88 for functional response of macrophages to a group IIA-secreted phospholipase A2 from snake venom.

    PubMed

    Leiguez, Elbio; Giannotti, Karina Cristina; Moreira, Vanessa; Matsubara, Márcio Hideki; Gutiérrez, José María; Lomonte, Bruno; Rodríguez, Juan Pablo; Balsinde, Jesús; Teixeira, Catarina

    2014-01-01

    The snake venom MT-III is a group IIA secreted phospholipase A2 (sPLA2) enzyme with functional and structural similarities with mammalian pro-inflammatory sPLA2s of the same group. Previously, we demonstrated that MT-III directly activates the innate inflammatory response of macrophages, including release of inflammatory mediators and formation of lipid droplets (LDs). However, the mechanisms coordinating these processes remain unclear. In the present study, by using TLR2-/- or MyD88-/- or C57BL/6 (WT) male mice, we report that TLR2 and MyD88 signaling have a critical role in MT-III-induced inflammatory response in macrophages. MT-III caused a marked release of PGE2, PGD2, PGJ2, IL-1β and IL-10 and increased the number of LDs in WT macrophages. In MT-III-stimulated TLR2-/- macrophages, formation of LDs and release of eicosanoids and cytokines were abrogated. In MyD88-/- macrophages, MT-III-induced release of PGE2, IL-1β and IL-10 was abrogated, but release of PGD2 and PGJ2 was maintained. In addition, COX-2 protein expression seen in MT-III-stimulated WT macrophages was abolished in both TLR2-/- and MyD88-/- cells, while perilipin 2 expression was abolished only in MyD88-/- cells. We further demonstrated a reduction of saturated, monounsaturated and polyunsaturated fatty acids and a release of the TLR2 agonists palmitic and oleic acid from MT-III-stimulated WT macrophages compared with WT control cells, thus suggesting these fatty acids as major messengers for MT-III-induced engagement of TLR2/MyD88 signaling. Collectively, our findings identify for the first time a TLR2 and MyD88-dependent mechanism that underlies group IIA sPLA2-induced inflammatory response in macrophages. PMID:24718259

  8. 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. PMID:26910028

  9. 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.

  10. Comparison of the mean quality factors for astronauts calculated using the Q-functions proposed by ICRP, ICRU, and NASA

    NASA Astrophysics Data System (ADS)

    Sato, T.; Endo, A.; Niita, K.

    2013-07-01

    For the estimation of the radiation risk for astronauts, not only the organ absorbed doses but also their mean quality factors must be evaluated. Three functions have been proposed by different organizations for expressing the radiation quality, including the Q(L), Q(y), and QNASA(Z, E) relationships as defined in International Committee of Radiological Protection (ICRP) Publication 60, International Commission on Radiation Units and Measurements (ICRU) Report 40, and National Aeronautics and Space Administration (NASA) TP-2011-216155, respectively. The Q(L) relationship is the most simple and widely used for space dosimetry, but the use of the latter two functions enables consideration of the difference in the track structure of various charged particles during the risk estimation. Therefore, we calculated the mean quality factors in organs and tissues in ICRP/ICRU reference voxel phantoms for the isotropic exposure to various mono-energetic particles using the three Q-functions. The Particle and Heavy Ion Transport code System PHITS was employed to simulate the particle motions inside the phantoms. The effective dose equivalents and the phantom-averaged effective quality factors for the astronauts were then estimated from the calculated mean quality factors multiplied by the fluence-to-dose conversion coefficients and cosmic-ray fluxes inside a spacecraft. It was found from the calculations that QNASA generally gives the largest values for the phantom-averaged effective quality factors among the three Q-functions for neutron, proton, and lighter-ion irradiation, whereas Q(L) provides the largest values for heavier-ion irradiation. Overall, the introduction of QNASA instead of Q(L) or Q(y) in astronaut dosimetry results in the increase the effective dose equivalents because the majority of the doses are composed of the contributions from protons and neutrons, although this tendency may change by the calculation conditions.

  11. 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

  12. Critical Role of TLR2 and MyD88 for Functional Response of Macrophages to a Group IIA-Secreted Phospholipase A2 from Snake Venom

    PubMed Central

    Leiguez, Elbio; Giannotti, Karina Cristina; Moreira, Vanessa; Matsubara, Márcio Hideki; Gutiérrez, José María; Lomonte, Bruno; Rodríguez, Juan Pablo; Balsinde, Jesús; Teixeira, Catarina

    2014-01-01

    The snake venom MT-III is a group IIA secreted phospholipase A2 (sPLA2) enzyme with functional and structural similarities with mammalian pro-inflammatory sPLA2s of the same group. Previously, we demonstrated that MT-III directly activates the innate inflammatory response of macrophages, including release of inflammatory mediators and formation of lipid droplets (LDs). However, the mechanisms coordinating these processes remain unclear. In the present study, by using TLR2−/− or MyD88−/− or C57BL/6 (WT) male mice, we report that TLR2 and MyD88 signaling have a critical role in MT-III-induced inflammatory response in macrophages. MT-III caused a marked release of PGE2, PGD2, PGJ2, IL-1β and IL-10 and increased the number of LDs in WT macrophages. In MT-III-stimulated TLR2−/− macrophages, formation of LDs and release of eicosanoids and cytokines were abrogated. In MyD88−/− macrophages, MT-III-induced release of PGE2, IL-1β and IL-10 was abrogated, but release of PGD2 and PGJ2 was maintained. In addition, COX-2 protein expression seen in MT-III-stimulated WT macrophages was abolished in both TLR2−/− and MyD88−/− cells, while perilipin 2 expression was abolished only in MyD88−/− cells. We further demonstrated a reduction of saturated, monounsaturated and polyunsaturated fatty acids and a release of the TLR2 agonists palmitic and oleic acid from MT-III-stimulated WT macrophages compared with WT control cells, thus suggesting these fatty acids as major messengers for MT-III-induced engagement of TLR2/MyD88 signaling. Collectively, our findings identify for the first time a TLR2 and MyD88-dependent mechanism that underlies group IIA sPLA2-induced inflammatory response in macrophages. PMID:24718259

  13. [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.

  14. 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.

  15. 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

    2009-04-01

    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.

  16. 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.

  17. Influences of parameter uncertainties within the ICRP-66 respiratory tract model: regional tissue doses for 239PuO2 and 238UO2/238U3O8.

    PubMed

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

    2003-04-01

    This paper extends an examination of the influence of parameter uncertainties on regional doses to respiratory tract tissues for short-ranged alpha particles using the ICRP-66 respiratory tract model. Previous papers examined uncertainties in the deposition and clearance aspects of the model. The critical parameters examined in this study included target tissue depths, thicknesses, and masses, particularly within the thoracic or lung regions of the respiratory tract. Probability density functions were assigned for the parameters based on published data. The probabilistic computer code LUDUC (Lung Dose Uncertainty Code) was used to assess regional and total lung doses from inhaled aerosols of 239PuO2 and 238UO2/238U3O8. Dose uncertainty was noted to depend on the particle aerodynamic diameter. Additionally, dose distributions were found to follow a lognormal distribution pattern. For 239PuO2 and 238UO2/238U3O8, this study showed that the uncertainty in lung dose increases by factors of approximately 50 and approximately 70 for plutonium and uranium oxides, respectively, over the particle size range from 0.1 to 20 microm. For typical exposure scenarios involving both radionuclides, the ratio of the 95% dose fractile to the 5% dose fractile ranged from approximately 8-10 (corresponding to a geometric standard deviation, or GSD, of about 1.7-2) for particle diameters of 0.1 to 1 microm. This ratio increased to about 370 for plutonium oxide (GSD approximately 4.5) and to about 600 for uranium oxide (GSD approximately 5) as the particle diameter approached 20 microm. However, thoracic tissue doses were quite low at larger particle sizes because most of the deposition occurred in the extrathoracic airways. For 239PuO2, median doses from LUDUC were found be in general agreement with those for Reference Man (via deterministic LUDEP 2.0 calculations) in the particle range of 0.1 to 5 microm. However, median doses to the basal cell nuclei of the bronchial airways (BB

  18. 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

  19. Daily uranium excretion in German peacekeeping personnel serving on the Balkans compared to ICRP model prediction.

    PubMed

    Oeh, U; Li, W B; Höllriegl, V; Giussani, A; Schramel, P; Roth, P; Paretzke, H G

    2007-01-01

    An investigation was performed to assess a possible health risk of depleted uranium (DU) for residents and German peacekeeping personnel serving on the Balkans. In order to evaluate a possible DU intake, the urinary uranium excretions of volunteers were collected and analysed using inductively coupled plasma mass spectrometry (ICP-MS). In total, more than 1300 urine samples from soldiers, civil servants and unexposed controls of different genders and ages were analysed to determine uranium excretion parameters. All participating volunteers, aged 3-92 y, were grouped according to their gender and age for evaluation. The results of the investigation revealed no significant difference between the unexposed controls and the peacekeeping personnel. In addition, the geometric means of the daily urinary excretion in peacekeeping personnel, ranging from 3 to 23 ng d(-1) for different age groups, fall toward the lower end of renal uranium excretion values published for unexposed populations in literature. The measured data were compared with the International Commission on Radiological Protection prediction for the intake of natural uranium by unexposed members of the public. The two data sets are in good agreement, indicating that no relevant intake of additional uranium, either natural or DU, has appeared for German peacekeeping personnel serving on the Balkans. PMID:17567762

  20. "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…

  1. Diagnostic reference levels for medical exposure of patients: ICRP guidance and related ICRU quantities.

    PubMed

    Rosenstein, Marvin

    2008-11-01

    In Publication 60 of the International Commission on Radiological Protection reference levels were described as values of measured quantities at which some specified action or decision should be taken. One particular form of reference level, the diagnostic reference level, applies specifically to medical exposure of patients. The objective of a diagnostic reference level is to help avoid radiation dose to the patient that does not contribute to the clinical purpose of a medical imaging task. This is accomplished by comparison between the numerical value of the diagnostic reference level and the mean or other appropriate value observed in practice for a suitable reference group of patients or a suitable reference phantom. A diagnostic reference level is not applied to individual patients. Diagnostic reference levels have no direct linkage to the numerical values for dose limits or dose constraints, and it is inappropriate to use them for regulatory or commercial purposes. Diagnostic reference levels should be selected by professional medical bodies (often in conjunction with health and radiation protection authorities) and their values may be specific to a country or region. A diagnostic reference level can be used: (1) to improve a regional, national or local distribution of observed results for a general medical imaging task, by reducing the frequency of unjustified high or low values; (2) to promote attainment of a narrower range of values that represent good practice for a more specific medical imaging task; or (3) to promote attainment of an optimum range of values for a specified medical imaging protocol. Authorized bodies are encouraged to set diagnostic reference levels that best meet their specific needs and that are consistent for the regional, national or local area to which they apply. Report 74 of the International Commission on Radiation Units and Measurements includes a commentary regarding quantities useful in establishing diagnostic reference levels

  2. Entrustable professional activities and curricular milestones for fellowship training in pulmonary and critical care medicine: report of a multisociety working group.

    PubMed

    Fessler, Henry E; Addrizzo-Harris, Doreen; Beck, James M; Buckley, John D; Pastores, Stephen M; Piquette, Craig A; Rowley, James A; Spevetz, Antoinette

    2014-09-01

    This article describes the curricular milestones and entrustable professional activities for trainees in pulmonary, critical care, or combined fellowship programs. Under the Next Accreditation System of the Accreditation Council for Graduate Medical Education (ACGME), curricular milestones compose the curriculum or learning objectives for training in these fields. Entrustable professional activities represent the outcomes of training, the activities that society and professional peers can expect fellowship graduates to be able to perform unsupervised. These curricular milestones and entrustable professional activities are the products of a consensus process from a multidisciplinary committee of medical educators representing the American College of Chest Physicians (CHEST), the American Thoracic Society, the Society of Critical Care Medicine, and the Association of Pulmonary and Critical Care Medicine Program Directors. After consensus was achieved using the Delphi process, the document was revised with input from the sponsoring societies and program directors. The resulting lists can serve as a roadmap and destination for trainees, program directors, and educators. Together with the reporting milestones, they will help mark trainees' progress in the mastery of the six ACGME core competencies of graduate medical education. PMID:24945874

  3. 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

  4. 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.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  6. 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. PMID:27187276

  7. 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…

  8. 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).

  9. Fluence-to-dose conversion coefficients for heavy ions calculated using the PHITS code and the ICRP/ICRU adult reference computational phantoms

    NASA Astrophysics Data System (ADS)

    Sato, Tatsuhiko; Endo, Akira; Niita, Koji

    2010-04-01

    The fluence to organ-absorbed-dose and effective-dose conversion coefficients for heavy ions with atomic numbers up to 28 and energies from 1 MeV/nucleon to 100 GeV/nucleon were calculated using the PHITS code coupled to the ICRP/ICRU adult reference computational phantoms, following the instruction given in ICRP Publication 103 (2007 (Oxford: Pergamon)). 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 absorbed dose in terms of LET (L) and lineal energy (y), respectively, implemented in PHITS. The calculation results indicate that the effective dose can generally give a conservative estimation of the effective dose equivalent for heavy-ion exposure, although it is occasionally too conservative especially for high-energy lighter-ion irradiations. It is also found from the calculation that the conversion coefficients for the Q(y)-based effective dose equivalents are generally smaller than the corresponding Q(L)-based values because of the conceptual difference between LET and y as well as the numerical incompatibility between the Q(L) and Q(y) relationships. The calculated data of these dose conversion coefficients are very useful for the dose estimation of astronauts due to cosmic-ray exposure.

  10. Fluence-to-dose conversion coefficients for heavy ions calculated using the PHITS code and the ICRP/ICRU adult reference computational phantoms.

    PubMed

    Sato, Tatsuhiko; Endo, Akira; Niita, Koji

    2010-04-21

    The fluence to organ-absorbed-dose and effective-dose conversion coefficients for heavy ions with atomic numbers up to 28 and energies from 1 MeV/nucleon to 100 GeV/nucleon were calculated using the PHITS code coupled to the ICRP/ICRU adult reference computational phantoms, following the instruction given in ICRP Publication 103 (2007 (Oxford: Pergamon)). 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 absorbed dose in terms of LET (L) and lineal energy (y), respectively, implemented in PHITS. The calculation results indicate that the effective dose can generally give a conservative estimation of the effective dose equivalent for heavy-ion exposure, although it is occasionally too conservative especially for high-energy lighter-ion irradiations. It is also found from the calculation that the conversion coefficients for the Q(y)-based effective dose equivalents are generally smaller than the corresponding Q(L)-based values because of the conceptual difference between LET and y as well as the numerical incompatibility between the Q(L) and Q(y) relationships. The calculated data of these dose conversion coefficients are very useful for the dose estimation of astronauts due to cosmic-ray exposure. PMID:20354281

  11. 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.

  12. 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…

  13. 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. PMID:22962600

  14. 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

  15. 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…

  16. 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. PMID:9676324

  17. 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.

  18. Critical assumptions: thinking critically about critical thinking.

    PubMed

    Riddell, Thelma

    2007-03-01

    The concept of critical thinking has been featured in nursing literature for the past 20 years. It has been described but not defined by both the American Association of Colleges of Nursing and the National League for Nursing, although their corresponding accreditation bodies require that critical thinking be included in nursing curricula. In addition, there is no reliable or valid measurement tool for critical thinking ability in nursing. As a result, there is a lack of research support for the assumptions that critical thinking can be learned and that critical thinking ability improves clinical competence. Brookfield suggested that commitments should be made only after a period of critically reflective analysis, during which the congruence between perceptions and reality are examined. In an evidence-based practice profession, we, as nurse educators, need to ask ourselves how we can defend our assumptions that critical thinking can be learned and that critical thinking improves the quality of nursing practice, especially when there is virtually no consensus on a definition.

  19. 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

    2010-07-01

    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

  20. 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 ...

  1. 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…

  2. 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. PMID:27218296

  3. 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.

  4. 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.

  5. 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…

  6. 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…

  7. 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…

  8. 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

  9. 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…

  10. 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…

  11. 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. PMID:20835833

  12. 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.

  13. 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, and…

  14. 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…

  15. 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.

  16. 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.

  17. 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)

  18. Militarily Critical Technology Program

    NASA Astrophysics Data System (ADS)

    Doherty, J.; Wick, R.; Sellers, P.

    The Militarily Critical Technology Program (MCTP) creates two technology lists: Militarily Critical Technology List (MCTL), which is focused on protecting US technology, and Developing Science and Technology List (DSTL). There are 20 different technology areas; two in particular are discussed in this poster paper, Space Systems Technologies and Lasers & Optics Technologies. The authors are the Technology Working Group chairs for Space Systems (Jim Doherty) and Lasers & Optics (Ray Wick), both from Institute for Defense Analyses (IDA), and also IDAs task leader for the MCTP (Paul Sellers).

  19. 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;…

  20. 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.

  1. 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.

  2. [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.

  3. 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.

  4. Training Groups, Encounter Groups, Sensitivity Groups and Group Psychotherapy

    PubMed Central

    Gottschalk, Louis A.; Pattison, E. Mansell; Schafer, Donald W.

    1971-01-01

    Descriptions and comparison of group therapies and the new group procedures (training groups and sensitivity groups—an outgrowth of the so-called Laboratory Movement methods of the mid-1930's) have been provided for the better understanding of non-psychiatric physicians. A group leader must have proper training and must help his group in its search for its avowed goals, whether he is a group therapist, a sensitivity trainer, or anyone else interested in utilizing group processes. Those goals are either the therapeutic benefit of the individual, as defined in group psychotherapy, or a better understanding of how one functions in groups, as in T-groups or the other group processes in the area of sensitive living. All group situations contain powerful tools which must be handled with proper respect. When so handled by experienced leaders, the individuals involved can achieve their goals in these group experiences. PMID:18730582

  5. Group Counseling

    ERIC Educational Resources Information Center

    Mahler, Clarence A.

    1971-01-01

    This article reviews the major concerns of group counseling and differentiates among group guidance, group counseling, and group therapy. It also evaluates the research status of group counseling and presents implications for the future of this approach. Comment by Carl E. Thoresen follows. (Author)

  6. 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,…

  7. 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

  8. 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…

  9. 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.

  10. 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 criteria and…

  11. A Verbal Analysis of Forms of Self-Criticism.

    ERIC Educational Resources Information Center

    Whelton, William J.; Henkelman, Julie J.

    2002-01-01

    An ongoing study aims to differentiate functional uses of self-criticism from destructive self-criticism. Self-criticisms and responses of 22 senior undergraduates were grouped into 8 categories covering a broad variety of self-criticisms. The final portion of the study will compare the content and form of self-criticisms of individuals with or…

  12. 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…

  13. 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

  14. 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.

  15. 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: Concepts, Skills,…

  16. 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, and goal…

  17. Critical Thinking in Adulthood.

    ERIC Educational Resources Information Center

    Fulton, Rodney D.

    Critical thinking is often defined as that which a particular instrument measures. The most prominent tests are the Watson-Glaser Critical Thinking Appraisal, the Ennis-Weir Critical Thinking Essay Test, and the Cornell Critical Thinking Tests. Watson and Glaser's (1980) view of critical thinking is "a composite of attitudes, knowledge, and…

  18. 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.

  19. Critical Care in Critical Access Hospitals.

    PubMed

    Seright, Teresa J; Winters, Charlene A

    2015-10-01

    What began as a grant-funded demonstration project, as a means of bridging the gap in rural health care, has developed into a critical access hospital system comprising 1328 facilities across 45 states. A critical access hospital is not just a safety net for health care in a rural community. Such hospitals may also provide specialized services such as same-day surgery, infusion therapy, and intensive care. For hospitals located near the required minimum of 35 miles from a tertiary care center, management of critically ill patients may be a matter of stabilization and transfer. Critical access hospitals in more rural areas are often much farther from tertiary care; some of these hospitals are situated within frontier areas of the United States. This article describes the development of critical access hospitals, provision of care and services, challenges to critical care in critical access hospitals, and suggestions to address gaps in research and collaborative care.

  20. 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

  1. 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.

  2. 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.

  3. Critical Care Team

    MedlinePlus

    ... Please enable scripts and reload this page. About Critical Care Currently selected Team Questions During the ICU Chronic ... Team Currently selected Questions Patients and Families > About Critical Care > Team Tweet Team Page Content ​The critical care ...

  4. 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.

  5. 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…

  6. 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…

  7. Diminazene or berenil, a classic duplex minor groove binder, binds to G-quadruplexes with low nanomolar dissociation constants and the amidine groups are also critical for G-quadruplex binding.

    PubMed

    Zhou, Jie; Le, Vu; Kalia, Dimpy; Nakayama, Shizuka; Mikek, Clinton; Lewis, Edwin A; Sintim, Herman O

    2014-10-01

    G-quadruplexes have shown great promise as chemotherapeutic targets, probably by inhibiting telomere elongation or downregulating oncogene expression. There have been many G-quadruplex ligands developed over the years but only a few have drug-like properties. Consequently only a few G-quadruplex ligands have entered clinical trials as cancer chemotherapeutic agents. The DNA minor groove ligand, berenil (diminazene aceturate or DMZ), is used to treat animal trypanosomiasis and hence its toxicological profile is already known, making it an ideal platform to engineer into new therapeutics. Herein, using a plethora of biophysical methods including UV, NMR, MS and ITC, we show that DMZ binds to several G-quadruplexes with a Kd of ∼1 nM. This is one of the strongest G-quadruplex binding affinities reported to date and is 10(3) tighter than the berenil affinity for an AT-rich duplex DNA. Structure-activity-relationship studies demonstrate that the two amidine groups on DMZ are important for binding to both G-quadruplex and duplex DNA. This work reveals that DMZ or berenil is not as selective for AT-rich duplexes as originally thought and that some of its biological effects could be manifested through G-quadruplex binding. The DMZ scaffold represents a good starting point to develop new G-quadruplex ligands for cancer cell targeting. PMID:25096593

  8. 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…

  9. 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…

  10. 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.

  11. Critical Approaches to Critical Pedagogy in Greece

    ERIC Educational Resources Information Center

    Grollios, George; Liambas, Anastassios

    2015-01-01

    This paper is an initial review of the presentations and uses of critical pedagogy in Greek educational literature since the mid-1980s. These have appeared in the form of three books and an edited volume (translated in Greek), all written by American critical educators, as well as in texts produced by Greek educators who have either written the…

  12. 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…

  13. 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…

  14. 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

  15. 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

  16. Teaching critical thinking.

    PubMed

    Holmes, N G; Wieman, Carl E; Bonn, D A

    2015-09-01

    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.

  17. Group dynamics.

    PubMed

    Scandiffio, A L

    1990-12-01

    Group dynamics play a significant role within any organization, culture, or unit. The important thing to remember with any of these structures is that they are made up of people--people with different ideas, motivations, background, and sometimes different agendas. Most groups, formal or informal, look for a leader in an effort to maintain cohesiveness of the unit. At times, that cultural bond must be developed; once developed, it must be nurtured. There are also times that one of the group no longer finds the culture comfortable and begins to act out behaviorally. It is these times that become trying for the leader as she or he attempts to remain objective when that which was once in the building phase of group cohesiveness starts to fall apart. At all times, the manager must continue to view the employee creating the disturbance as an integral part of the group. It is at this time that it is beneficial to perceive the employee exhibiting problem behaviors as a special employee, as one who needs the benefit of your experience and skills, as one who is still part of the group. It is also during this time that the manager should focus upon her or his own views in the area of power, communication, and the corporate culture of the unit that one has established before attempting to understand another's point of view. Once we understand our own motivation and accept ourselves, it is then that we may move on to offer assistance to another. Once we understand our insecurities recognizing staff dysfunction as a symptom of system dysfunction will not be so threatening to the concept of the manager that we perceive ourselves to be. It takes a secure person to admit that she or he favors staff before deciding to do something to change things. The important thing to know is that it can be done. The favored staff can find a new way of relating to others, the special employee can find new modes of behavior (and even find self-esteem in the process), the group can find new ways

  18. 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…

  19. 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.

  20. 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)

  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 anthropometry for menarche.

    PubMed

    Gonzales, G F; Villena, A

    1996-08-01

    The objective of the study was to determine if any anthropometric measurements, including weight, height, and upper arm circumference, or the calculated body mass index observed at the time of menarche may be used as a threshold for menarche. The sample was randomly selected from 1133 girls aged 10-18 years from two groups, one residing in Lima, Peru, at 150 m above sea level, and the second in Cerro de Pasco, Peru, at 4340 m above sea level. For the purpose of this study, all girls who reached menarche at least 1 month before the study (n = 93) were considered as cases (girls at menarche); 88 girls without menarche at the time of the study were randomly matched by age and place of residence, and designated as controls. All subjects came from the same low socioeconomic status. Body weight at menarche was 44.6 +/- 5.09 kg (mean +/- SD; coefficient of variation [CV], 11.4%). Height at menarche was 151.6 +/- 5.5 cm (CV, 3.7%). Body mass index, defined as weight/height2.15, was 18.26 +/- 1.96 kg/m2.15 at menarche (CV, 10.7%). Upper arm circumference at menarche was 21.8 +/- 1.6 cm (CV, 7.3%). The logistic regression analysis showed that any of the four anthropometric measurements analyzed were critical for menarche; i.e., any of the four could be used as a threshold for menarche. Data from the present study do not support the hypothesis that there are anthropometric markers that are critical for menarche.

  3. Anomalous critical fields in quantum critical superconductors.

    PubMed

    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(As(1-x)P(x))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

  4. 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

  5. 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.

  6. Group Psychotherapy in Sweden.

    PubMed

    Ahlin, Göran

    2015-10-01

    The paper presents an overview of the national developments of group psychotherapy (GPS) in Sweden during the period from World War II until the present time. Methods and concepts, imported primarily from England and the United States, inspired trainings and widespread psychodynamic and group analytic applications in schools, health treatment, and social care. Education in psychotherapy and GPS at universities opened new therapeutic and vocational areas during the period 1970-2005. Increasing criticism of psychodynamics, as in other Western societies, but more radical in Sweden, has in the last decades made group analytic GPS diminish in favor of cognitive behavioral therapy models. Prospects for GPS further development may presently look bleak but, in a longer perspective, are promising.

  7. 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.

  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. 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…

  10. 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 at a…

  11. 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…

  12. 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…

  13. 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...

  14. 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.

  15. 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…

  16. Comparison of observed lung retention and urinary excretion of thorium workers and members of the public in India with the values predicted by the ICRP biokinetic model.

    PubMed

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

    2004-01-01

    The daily intake of natural Th and its contents in lungs, skeleton and liver of an Indian adult population group were estimated using radiochemical neutron activation analysis (RNAA) technique. These data on daily intake (through inhalation and ingestion) were used to compute Th contents in lungs and other systemic organs such as skeleton and liver using the new human respiratory tract model (HRTM) and the new biokinetic model of Th. The theoretically computed Th contents in lungs, skeleton and liver of an average Indian adult are 2.56, 4.00 and 0.17 microg, respectively which are comparable with the corresponding experimentally measured values of 4.31, 3.45 and 0.14 microg in an urban population group living in Mumbai. The measured lung contents of Th in a group of five occupational workers were used to compute their total body Th contents and the corresponding daily urinary excretions. The computed total body contents and daily urinary excretions of Th in the five subjects compared favourably with their measured values. These studies, thus, validate the new biokinetic model of Th in natural as well as in occupational exposures in Indian conditions. PMID:15292523

  17. Defining critical thoughts.

    PubMed

    Lovatt, Abbie

    2014-05-01

    Nursing education has long struggled to define critical thinking and explain how the process of critical thinking fits into the context of nursing. Despite this long time struggle, nurses and nurse educators continue to strive to foster critical thinking skills in nursing students as intuitively most nurses believe that critical thinking is necessary to function competently in the workplace. This article explores the most recent work of Dr. Stephen Brookfield and ties the concepts which are explored in Brookfield's work to nursing practice. Brookfield identifies that learners understand the meaning of critical thinking the best when the process is first demonstrated. Role modeling is a method educators can use to demonstrate critical thinking and is a strategy which nurses often use in the clinical area to train and mentor new nursing staff. Although it is not a new strategy in nursing education, it is a valuable strategy to engage learners in critical thinking activities. PMID:24418065

  18. 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.

  19. 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.

  20. 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…

  1. 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).

  2. 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.

  3. 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.

  4. 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.

  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. 75 FR 5146 - Hewlett Packard Company Business Critical Systems, Mission Critical Business Software Division...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-01

    ... Register November 5, 2009 (74 FR 57341). At the request of the State Agency, the Department reviewed the... Business Software Division, OpenVMS Operating System Development Group, Including Employees Working Off... Business Critical Systems, Mission Critical Business Software Division, OpenVMS Operating...

  7. 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)

  8. Critical Thinking in Math.

    ERIC Educational Resources Information Center

    Ronis, Diane

    This booklet includes a wheel of problem solving strategies and a seven-step process for approaching and solving complicated problems. The information provided gives students a variety of ways to approach, analyze, and think critically about mathematics problems. The chapters present guides to promoting critical thinking in cooperative groups…

  9. 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 developed…

  10. 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…

  11. 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…

  12. 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…

  13. Critical Teaching and Learning.

    ERIC Educational Resources Information Center

    Young, R. E.

    1988-01-01

    This essay begins with a description of Jurgen Habermas's theory of communicative action, emphasizing aspects which relate to a critical theory of teaching/learning. Existing theory and research is reviewed. A critical theory of pedagogy as a form of communicative action or interaction is presented. (MT)

  14. Critical Education Studies

    ERIC Educational Resources Information Center

    Boxley, Simon

    2015-01-01

    Education Studies as an academic discipline within HE in the UK is a contested area. One thing most Education Studies programmes might agree on is that they are "critical". But what is a genuinely critical Education Studies degree? And, how could such a programme survive within the hostile neoliberal environment of the contemporary UK?…

  15. Critical Social Numeracy.

    ERIC Educational Resources Information Center

    Lake, David

    2002-01-01

    Presents a five-step method to develop the critical numeracy knowledge of numerically intimidated students. Examines the method in detail, discussing Piagetian diagnostic tools and how to adapt the Structure of the Observed Learning Outcome (SOLO) taxonomy to teach critical numeracy. (CMK)

  16. 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...

  17. 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…

  18. Title X and its critics.

    PubMed

    Rosoff, J I; Kenney, A M

    1984-01-01

    On Arpil 5, 1984 Senator Jesse Helms (R.--NC) was the leadd witness at a hearing before the US Senate Labor and Human Resources Subcommittee on Family and Human Services. The subcommittee was considering the renewal of Title X of the Public Health Service Act, the main national family planning legislation. Helm's prepared text (given in this article) was noteworthy not only for its hyperbole but also for its tone of intense frustration and for its repetition of the main themes enunciated by those less well known and less powerful who have opposed the program since it began. Title X was 1st enacted in 1970 and was reenacted in 1973, 1975, 1977, 1978 and 1981. The program has always had its share of critics; but in the late 1970's with the emergence of the New Right, such groups moved into political power. Title X provided for project grants to be made to public and private nonprofit agencies to provide contraceptive services along with training, technical assistance and other support activities. It also spelled out government responsibilities and functions in relation to human reproduction and population research; and it created the post of Deputy Assistant Secretary for Population Affairs, with direct responsibility for both types of activities within the Department of Health and Human Services. Eligibility for services was broad--applying to all who need and want services, with priority for low-income persons. A requirement of voluntary participation and a prohibition of the use of Title X funds for abortion as a family planning method were clearly stated. Title X has been criticized by Catholics and many other groups. This article attempts to meet criticisms aimed at the functioning, appropriateness and impact of the Title X program, and summarizes the findings of a large body of socialogical and demographic research that has direct or indirect bearing on the issues raised by the critics.

  19. Critical Schwinger Pair Production.

    PubMed

    Gies, Holger; Torgrimsson, Greger

    2016-03-01

    We investigate Schwinger pair production in spatially inhomogeneous electric backgrounds. A critical point for the onset of pair production can be approached by fields that marginally provide sufficient electrostatic energy for an off-shell long-range electron-positron fluctuation to become a real pair. Close to this critical point, we observe features of universality which are analogous to continuous phase transitions in critical phenomena with the pair-production rate serving as an order parameter: electric backgrounds can be subdivided into universality classes and the onset of pair production exhibits characteristic scaling laws. An appropriate design of the electric background field can interpolate between power-law scaling, essential Berezinskii-Kosterlitz-Thouless-type scaling, and a power-law scaling with log corrections. The corresponding critical exponents only depend on the large-scale features of the electric background, whereas the microscopic details of the background play the role of irrelevant perturbations not affecting criticality. PMID:26991162

  20. 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

  1. 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.

  2. 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…

  3. Higher Education: A Critical Business.

    ERIC Educational Resources Information Center

    Barnett, Ronald

    Current concepts of critical thinking need to be reconstrued into the much broader concept of "critical being" and applied to higher education. Under this construct, critical persons (students) become more than just critical thinkers; they engage critically with the world and with themselves; they not only reflect critically on knowledge, but also…

  4. 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.

  5. 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

  6. 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.

  7. Looking at Gestalt Group Impact: An Experiment.

    ERIC Educational Resources Information Center

    Serok, Shraga; Bar, Ruth

    1984-01-01

    Tested the impact of gestalt group therapy on aspects of self-concept in graduate students (N=33). Results showed a significant rise in decisiveness, general adaptation and self-criticism in the gestalt group as compared to the control groups and showed no significant changes in the self-identification and self-acceptance parameters. (LLL)

  8. Literature Study Groups: Literacy Learning "with Legs"

    ERIC Educational Resources Information Center

    Parsons, Sue Christian; Mokhtari, Kouider; Yellin, David; Orwig, Ryan

    2011-01-01

    Literature study groups help promote critical thinking and improve reading skills. These groups, in general, are characterized by: (1) a flexible grouping--usually determined by a reader's choice of a given book at a given time; (2) participant-centered dialogue, where the teacher takes on the role of facilitator and expert participant rather than…

  9. Critical-point nuclei

    SciTech Connect

    Clark, R.M.

    2004-10-01

    It has been suggested that a change of nuclear shape may be described in terms of a phase transition and that specific nuclei may lie close to the critical point of the transition. Analytical descriptions of such critical-point nuclei have been introduced recently and they are described briefly. The results of extensive searches for possible examples of critical-point behavior are presented. Alternative pictures, such as describing bands in the candidate nuclei using simple {Delta}K = 0 and {Delta}K = 2 rotational-coupling models, are discussed, and the limitations of the different approaches highlighted. A possible critical-point description of the transition from a vibrational to rotational pairing phase is suggested.

  10. 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)

  11. Critical Access Hospitals (CAH)

    MedlinePlus

    ... CAH Conditions of Participation . What are the location requirements for CAH status? Critical Access Hospitals must be ... clinic that does not meet the CAH distance requirements? As of January 1, 2008, all CAHs, including ...

  12. 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.

  13. Quantum Critical Elasticity.

    PubMed

    Zacharias, Mario; Paul, Indranil; Garst, Markus

    2015-07-10

    We discuss elastic instabilities of the atomic crystal lattice at zero temperature. Because of long-range shear forces of the solid, at such transitions the phonon velocities vanish, if at all, only along certain crystallographic directions, and, consequently, the critical phonon fluctuations are suppressed to a lower dimensional manifold and governed by a Gaussian fixed point. In the case of symmetry-breaking elastic transitions, a characteristic critical phonon thermodynamics arises that is found, e.g., to violate Debye's T(3) law for the specific heat. We point out that quantum critical elasticity is triggered whenever a critical soft mode couples linearly to the strain tensor. In particular, this is relevant for the electronic Ising-nematic quantum phase transition in a tetragonal crystal as discussed in the context of certain cuprates, ruthenates, and iron-based superconductors. PMID:26207483

  14. About Critical Care Nursing

    MedlinePlus

    ... Join Now Our Community Value of Belonging Member Benefits and Savings Awards Certification Apply Online Renew Your ... and traveling critical care nurses to fill staffing gaps in every part of the U.S. These requests ...

  15. A leadership programme for critical care.

    PubMed

    Crofts, Linda

    2006-08-01

    This paper describes the genesis, design and implementation of a leadership programme for critical care. This was an initiative funded by the National Health Service (NHS) Nursing Leadership Project and had at the core of its design flexibility to meet the needs of the individual hospitals, which took part in it. Participation was from the multi-disciplinary critical care team. Six NHS hospitals took part in the programme which was of 20 days duration and took place on hospital sites. The programme used the leadership model of as its template and had a number of distinct components; a baseline assessment, personal development, principles of leadership and critical case reviews. The programme was underpinned by three themes; working effectively in multi-professional teams to provide patient focussed care, managing change through effective leadership and developing the virtual critical care service. Each group set objectives pertinent to their own organisation's needs. The programme was evaluated by a self-reporting questionnaire; group feedback and feedback from stakeholders. Programme evaluation was positive from all the hospitals but it was clear that the impact of the programme varied considerably between the groups who took part. It was noted that there was some correlation between the success of the programme and organisational 'buy in' as well as the organisational culture within which the participants operated. A key feature of the programme success was the critical case reviews, which were considered to be a powerful learning tool and medium for group learning and change management. PMID:16621563

  16. A leadership programme for critical care.

    PubMed

    Crofts, Linda

    2006-08-01

    This paper describes the genesis, design and implementation of a leadership programme for critical care. This was an initiative funded by the National Health Service (NHS) Nursing Leadership Project and had at the core of its design flexibility to meet the needs of the individual hospitals, which took part in it. Participation was from the multi-disciplinary critical care team. Six NHS hospitals took part in the programme which was of 20 days duration and took place on hospital sites. The programme used the leadership model of as its template and had a number of distinct components; a baseline assessment, personal development, principles of leadership and critical case reviews. The programme was underpinned by three themes; working effectively in multi-professional teams to provide patient focussed care, managing change through effective leadership and developing the virtual critical care service. Each group set objectives pertinent to their own organisation's needs. The programme was evaluated by a self-reporting questionnaire; group feedback and feedback from stakeholders. Programme evaluation was positive from all the hospitals but it was clear that the impact of the programme varied considerably between the groups who took part. It was noted that there was some correlation between the success of the programme and organisational 'buy in' as well as the organisational culture within which the participants operated. A key feature of the programme success was the critical case reviews, which were considered to be a powerful learning tool and medium for group learning and change management.

  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. Criticality of spent reactor fuel

    SciTech Connect

    Harris, D.R.

    1987-01-01

    The storage capacity of spent reactor fuel pools can be greatly increased by consolidation. In this process, the fuel rods are removed from reactor fuel assemblies and are stored in close-packed arrays in a canister or skeleton. An earlier study examined criticality consideration for consolidation of Westinghouse fuel, assumed to be fresh, in canisters at the Millstone-2 spent-fuel pool and in the General Electric IF-300 shipping cask. The conclusions were that the fuel rods in the canister are so deficient in water that they are adequately subcritical, both in normal and in off-normal conditions. One potential accident, the water spill event, remained unresolved in the earlier study. A methodology is developed here for spent-fuel criticality and is applied to the water spill event. The methodology utilizes LEOPARD to compute few-group cross sections for the diffusion code PDQ7, which then is used to compute reactivity. These codes give results for fresh fuel that are in good agreement with KENO IV-NITAWL Monte Carlo results, which themselves are in good agreement with continuous energy Monte Carlo calculations. These methodologies are in reasonable agreement with critical measurements for undepleted fuel.

  19. Criticality of metals and metalloids

    PubMed Central

    Graedel, T. E.; Harper, E. M.; Nassar, N. T.; Nuss, Philip; Reck, Barbara K.

    2015-01-01

    Imbalances between metal supply and demand, real or anticipated, have inspired the concept of metal criticality. We here characterize the criticality of 62 metals and metalloids in a 3D “criticality space” consisting of supply risk, environmental implications, and vulnerability to supply restriction. Contributing factors that lead to extreme values include high geopolitical concentration of primary production, lack of available suitable substitutes, and political instability. The results show that the limitations for many metals important in emerging electronics (e.g., gallium and selenium) are largely those related to supply risk; those of platinum group metals, gold, and mercury, to environmental implications; and steel alloying elements (e.g., chromium and niobium) as well as elements used in high-temperature alloys (e.g., tungsten and molybdenum), to vulnerability to supply restriction. The metals of most concern tend to be those available largely or entirely as byproducts, used in small quantities for highly specialized applications, and possessing no effective substitutes. PMID:25831527

  20. Critical exponents from cluster coefficients

    NASA Astrophysics Data System (ADS)

    Rotman, Z.; Eisenberg, E.

    2009-09-01

    For a large class of repulsive interaction models, the Mayer cluster integrals can be transformed into a tridiagonal real symmetric matrix Rmn , whose elements converge to two constants. This allows for an effective extrapolation of the equation of state for these models. Due to a nearby (nonphysical) singularity on the negative real z axis, standard methods (e.g., Padé approximants based on the cluster integrals expansion) fail to capture the behavior of these models near the ordering transition, and, in particular, do not detect the critical point. A recent work [E. Eisenberg and A. Baram, Proc. Natl. Acad. Sci. U.S.A. 104, 5755 (2007)] has shown that the critical exponents σ and σ' , characterizing the singularity of the density as a function of the activity, can be exactly calculated if the decay of the R matrix elements to their asymptotic constant follows a 1/n2 law. Here we employ renormalization group (RG) arguments to extend this result and analyze cases for which the asymptotic approach of the R matrix elements toward their limiting value is of a more general form. The relevant asymptotic correction terms (in RG sense) are identified, and we then present a corrected exact formula for the critical exponents. We identify the limits of usage of the formula and demonstrate one physical model, which is beyond its range of validity. The formula is validated numerically and then applied to analyze a number of concrete physical models.

  1. Critical experiment data archiving

    SciTech Connect

    Koponen, B.L. ); Clayton, E.D.; Doherty, A.L. )

    1991-01-01

    Critical experiment facilities produced a large number of important data during the past 45 years; however, many useful data remain unpublished. The unpublished material exists in the form of experimenters' logbooks, notes, photographs, material descriptions, etc., This data could be important for computer code validation, understanding the physics of criticality, facility design, or for setting process limits. In the past, criticality specialists have been able to obtain unpublished details by direct contact with the experimenters. Obviously, this will not be possible indefinitely. Most of the US critical experiment facilities are now closed, and the experimenters are moving to other jobs, retiring, or otherwise becoming unavailable for this informal assistance. Also, the records are in danger of being discarded or lost during facility closures, cleanup activities, or in storage. A project was begun in 1989 to ensure that important unpublished data from critical experiment facilities in the United States are archived and made available as a resource of the US Department of Energy's (DOE's) Nuclear Criticality Information System (NCIS). The objective of this paper is to summarize the project accomplishments to date and bring these activities to the attention of those who might be aware of the location of source information needed for archiving and could assist in getting the materials included in the archive.

  2. Mapping Self-Organized Criticality onto Criticality

    NASA Astrophysics Data System (ADS)

    Sornette, Didier; Johansen, Anders; Dornic, Ivan

    1995-03-01

    We present a general conceptual framework for self-organized criticality (SOC), based on the recognition that it is nothing but the expression, “unfolded" in a suitable parameter space, of an underlying unstable dynamical critical point. More precisely, SOC is shown to result from the tunning of the order parameter to a vanishingly small, but positive value, thus ensuring that the corresponding control parameter lies exactly at its critical value for the underlying transition. This clarifies the role and nature of the very slow driving rate common to all systems exhibiting SOC. This mechanism is shown to apply to models of sandpiles, earthquakes, depinning, fractal growth and forest fires, which have been proposed as examples of SOC. Nous proposons une stratégie générale pour identifier le mécanisme responsable des phénomènes critiques auto-organisés, basée, sur l'idée qu'ils sont simplement la traduction, dans un espace de paramètres choisis, d'un point critique dynamique instable standard. La criticalité auto-organisée résulte du contrôle du paramètre d'ordre ajusté à une valeur positive tendant vers zéro, ce qui assure automatiquement que le paramètre de contrôle correspondant se cale exactement sur sa valeur critique de la transition de critique sous-jacente. Ce résultat explique le rôle particulier joué par le forçage infiniment lent qui est un caractère commun à tous les systèmes critiques auto-organisés. Nous appliquons ces idées aux modèles de tas de sable, aux modèles de tremblements de terre, de feux de forêts, aux transitions de décrochage et aux modèles de croissance fractale, qui ont été proposés comme autant d'exemples caractéristiques de la criticalité auto-organisée.

  3. Renormalization Group Tutorial

    NASA Technical Reports Server (NTRS)

    Bell, Thomas L.

    2004-01-01

    Complex physical systems sometimes have statistical behavior characterized by power- law dependence on the parameters of the system and spatial variability with no particular characteristic scale as the parameters approach critical values. The renormalization group (RG) approach was developed in the fields of statistical mechanics and quantum field theory to derive quantitative predictions of such behavior in cases where conventional methods of analysis fail. Techniques based on these ideas have since been extended to treat problems in many different fields, and in particular, the behavior of turbulent fluids. This lecture will describe a relatively simple but nontrivial example of the RG approach applied to the diffusion of photons out of a stellar medium when the photons have wavelengths near that of an emission line of atoms in the medium.

  4. Improved Monte Carlo Renormalization Group Method

    DOE R&D Accomplishments Database

    Gupta, R.; Wilson, K. G.; Umrigar, C.

    1985-01-01

    An extensive program to analyze critical systems using an Improved Monte Carlo Renormalization Group Method (IMCRG) being undertaken at LANL and Cornell is described. Here we first briefly review the method and then list some of the topics being investigated.

  5. Erik Erikson: critical times, critical theory.

    PubMed

    Douvan, E

    1997-01-01

    The work and legacy of Erik Erikson are described in this brief outline of his career, his theories, and his impact on psychoanalysis, psychology, history, and the broader culture. His conception of the adolescent task-weaving internal tastes, talents, and values together with elements of one's life history and the demands of one's culture into a coherent identity-has had profound effects on developmental psychology and the way in which sophisticated youth construct and describe their lives. His extension of development through adulthood and old age established the field of life course development. His emphasis on the impact of history and culture on development was a critical element in the developing field of ego psychology. Many of his major contributions can be fruitfully understood in the context of his personal history and individual qualities. PMID:9256525

  6. Erik Erikson: critical times, critical theory.

    PubMed

    Douvan, E

    1997-01-01

    The work and legacy of Erik Erikson are described in this brief outline of his career, his theories, and his impact on psychoanalysis, psychology, history, and the broader culture. His conception of the adolescent task-weaving internal tastes, talents, and values together with elements of one's life history and the demands of one's culture into a coherent identity-has had profound effects on developmental psychology and the way in which sophisticated youth construct and describe their lives. His extension of development through adulthood and old age established the field of life course development. His emphasis on the impact of history and culture on development was a critical element in the developing field of ego psychology. Many of his major contributions can be fruitfully understood in the context of his personal history and individual qualities.

  7. Nuclear criticality information system

    SciTech Connect

    Koponen, B.L.; Hampel, V.E.

    1981-11-30

    The nuclear criticality safety program at LLNL began in the 1950's with a critical measurements program which produced benchmark data until the late 1960's. This same time period saw the rapid development of computer technology useful for both computer modeling of fissile systems and for computer-aided management and display of the computational benchmark data. Database management grew in importance as the amount of information increased and as experimental programs were terminated. Within the criticality safety program at LLNL we began at that time to develop a computer library of benchmark data for validation of computer codes and cross sections. As part of this effort, we prepared a computer-based bibliography of criticality measurements on relatively simple systems. However, it is only now that some of these computer-based resources can be made available to the nuclear criticality safety community at large. This technology transfer is being accomplished by the DOE Technology Information System (TIS), a dedicated, advanced information system. The NCIS database is described.

  8. Predictability of critical transitions

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaozhu; Kuehn, Christian; Hallerberg, Sarah

    2015-11-01

    Critical transitions in multistable systems have been discussed as models for a variety of phenomena ranging from the extinctions of species to socioeconomic changes and climate transitions between ice ages and warm ages. From bifurcation theory we can expect certain critical transitions to be preceded by a decreased recovery from external perturbations. The consequences of this critical slowing down have been observed as an increase in variance and autocorrelation prior to the transition. However, especially in the presence of noise, it is not clear whether these changes in observation variables are statistically relevant such that they could be used as indicators for critical transitions. In this contribution we investigate the predictability of critical transitions in conceptual models. We study the quadratic integrate-and-fire model and the van der Pol model under the influence of external noise. We focus especially on the statistical analysis of the success of predictions and the overall predictability of the system. The performance of different indicator variables turns out to be dependent on the specific model under study and the conditions of accessing it. Furthermore, we study the influence of the magnitude of transitions on the predictive performance.

  9. Criticality in Plasma Membranes

    NASA Astrophysics Data System (ADS)

    Machta, Benjamin; Papanikolaou, Stefanos; Sethna, James; Veatch, Sarah

    2011-03-01

    We are motivated by recent observations of micron-sized critical fluctuations in the 2d Ising Universality class in plasma membrane vesicles that are isolated from cortical cytoskeleton. We construct a minimal model of the plasma membrane's interaction with intact cytoskeleton which explains why large scale phase separation has not been observed in Vivo. In addition, we use analytical techniques from conformal field theory and numerical simulations to investigate the form of effective forces mediated by the membrane's proximity to criticality. We show that the range of this force is maximized near a critical point and we quantify its usefulness in mediating communication using techniques from information theory. Finally we use theoretical techniques from statistical physics in conjunction with Monte-Carlo simulations to understand how criticality can be used to increase the efficiency of membrane bound receptor mediated signaling. We expect that this sort of analysis will be broadly useful in understanding and quantifying the role of lipid ``rafts'' in a wide variety of membrane bound processes. Generally, we demonstrate that critical fluctuations provide a physical mechanism to organize and spatially segregate membrane components by providing channels for interaction over relatively large distances.

  10. Self-organized criticality

    SciTech Connect

    Per Bak ); Kan Chen )

    1991-01-01

    Just as the proverbial straw broke the camel's back, catastrophes, from earthquakes and avalanches to a stock market crash, can be triggered by a minor event. The authors argue that complex systems naturally evolve to a critical state. Their theory already has improved understanding of motion in the earth's crust, economies and ecosystems. The theory of self-organized criticality states that many composite systems naturally evolve to a critical state in which a minor event starts a chain reaction that can affect any number of elements in the system. Although composite systems produce more minor events than catastrophes, chain reactions of all sizes are an integral part of the dynamics. According to the theory, the mechanism that leads to minor events is the same one that leads to major events. Furthermore, composite systems never reach equilibrium but instead evolve from one metastable state to the next. Self-organized criticality is a holistic theory: the global features, such as the relative number of large and small events, do not depend on the microscopic mechanisms. Consequently, global features of the system cannot be understood by analyzing the parts separately. To the authors' knowledge, self-organized criticality is the only model or mathematical description that has led to a holistic theory for dynamic systems.

  11. Critical Management in Knowledge Organizations

    ERIC Educational Resources Information Center

    Macpherson, Reynold

    2008-01-01

    Purpose: The purpose of this paper is to invite educational managers and management educators to reflect critically on practice. Design/methodology/approach: Using the point of Socrates' death, the paper suggests ways of reflecting on actions using ethically-critical, socially-critical, environmentally-critical, politically-critical and…

  12. Critical Thinking in Business Education.

    ERIC Educational Resources Information Center

    Sormunen, Carolee

    Critical thinking is currently a prominent issue in education. For business educators, four issues must be considered: the meaning of critical thinking, how critical thinking can be introduced into the curriculum, how critical thinking is developed in courses, and how critical thinking can be evaluated. The literature identifies three theoretical…

  13. The Anatomy of Critical Discourse.

    ERIC Educational Resources Information Center

    Rosenfield, Lawrence W.

    1968-01-01

    Critical discourse is best understood when its logical features are identified. An examination of the basic elements and modes of rhetorical criticism (a form of critical discourse) produces a finite set of options for the critic, thus enabling him to develop a system of alternatives in his critical efforts. For example, by selecting from among…

  14. Morphogenesis at criticality?

    NASA Astrophysics Data System (ADS)

    Krotov, Dmitry; Dubuis, Julien; Gregor, Thomas; Bialek, William

    2014-03-01

    Spatial patterns in the early fruit fly embryo emerge from a network of interactions among transcription factors, the gap genes, driven by maternal inputs. Such networks can exhibit many qualitatively different behaviors, separated by critical surfaces. At criticality, we should observe strong correlations in the fluctuations of different genes around their mean expression levels, a slowing of the dynamics along some but not all directions in the space of possible expression levels, correlations of expression fluctuations over long distances in the embryo, and departures from a Gaussian distribution of these fluctuations. Analysis of recent experiments on the gap genes shows that all these signatures are observed, and that the different signatures are related in ways predicted by theory. While there might be other explanations for these individual phenomena, the confluence of evidence suggests that this genetic network is tuned to criticality.

  15. Interface localization near criticality

    NASA Astrophysics Data System (ADS)

    Delfino, Gesualdo

    2016-05-01

    The theory of interface localization in near-critical planar systems at phase coexistence is formulated from first principles. We show that mutual delocalization of two interfaces, amounting to interfacial wetting, occurs when the bulk correlation length critical exponent ν is larger than or equal to 1. Interaction with a boundary or defect line involves an additional scale and a dependence of the localization strength on the distance from criticality. The implications are particularly rich in the boundary case, where delocalization proceeds through different renormalization patterns sharing the feature that the boundary field becomes irrelevant in the delocalized regime. The boundary delocalization (wetting) transition is shown to be continuous, with surface specific heat and layer thickness exponents which can take values that we determine.

  16. Linear response at criticality

    NASA Astrophysics Data System (ADS)

    Svenkeson, Adam; Bologna, Mauro; Grigolini, Paolo

    2012-10-01

    We study a set of cooperatively interacting units at criticality, and we prove with analytical and numerical arguments that they generate the same renewal non-Poisson intermittency as that produced by blinking quantum dots, thereby giving a stronger support to the results of earlier investigation. By analyzing how this out-of-equilibrium system responds to harmonic perturbations, we find that the response can be described only using a new form of linear response theory that accounts for aging and the nonergodic behavior of the underlying process. We connect the undamped response of the system at criticality to the decaying response predicted by the recently established nonergodic fluctuation-dissipation theorem for dichotomous processes using information about the second moment of the fluctuations. We demonstrate that over a wide range of perturbation frequencies the response of the cooperative system is greatest when at criticality.

  17. Morphogenesis at criticality

    PubMed Central

    Krotov, Dmitry; Dubuis, Julien O.; Gregor, Thomas; Bialek, William

    2014-01-01

    Spatial patterns in the early fruit fly embryo emerge from a network of interactions among transcription factors, the gap genes, driven by maternal inputs. Such networks can exhibit many qualitatively different behaviors, separated by critical surfaces. At criticality, we should observe strong correlations in the fluctuations of different genes around their mean expression levels, a slowing of the dynamics along some but not all directions in the space of possible expression levels, correlations of expression fluctuations over long distances in the embryo, and departures from a Gaussian distribution of these fluctuations. Analysis of recent experiments on the gap gene network shows that all these signatures are observed, and that the different signatures are related in ways predicted by theory. Although there might be other explanations for these individual phenomena, the confluence of evidence suggests that this genetic network is tuned to criticality. PMID:24516161

  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. The sample cell at the heart of CVX-2 will sit inside a thermostat providing three layers of insulation. The cell itself comprises a copper body that conducts heat efficiently and smoothes out thermal variations that that would destroy the xenon's uniformity. Inside the cell, the oscillating screen viscometer element is supported between two pairs of electrodes that deflect the screen and then measure screen motion.

  19. 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 2001 will measure the viscous behavior of xenon, a heavy inert gas used in flash lamps and ion rocket engines, at its critical point. The thermostat for CVX sits inside the white cylinder on a support structure that is placed inside a pressure canister. A similar canister holds the electronics and control systems. The CVX-2 arrangement is identical. The principal investigator is Dr. Robert F. Berg (not shown) of the National Institutes of Standards and Technology, Gaithersburg, MD. This is a detail view of MSFC 0100143.

  20. Improving work group decision-making effectiveness.

    PubMed

    Schoonover-Shoffner, K

    1989-01-01

    Many of the decisions in complex health care organizations are made by small work groups. Nurse administrators often lead or are highly involved in these groups, where reaching quality decisions is a critical goal. This paper examines research and information from the communications field, presenting a model for making decisions in small groups. The author identifies common pitfalls of decision-making groups and presents strategies for problem solving and improved decision making.

  1. Nonequilibrium critical scaling in quantum thermodynamics

    NASA Astrophysics Data System (ADS)

    Bayat, Abolfazl; Apollaro, Tony J. G.; Paganelli, Simone; De Chiara, Gabriele; Johannesson, Henrik; Bose, Sougato; Sodano, Pasquale

    2016-05-01

    The emerging field of quantum thermodynamics is contributing important results and insights into archetypal many-body problems, including quantum phase transitions. Still, the question whether out-of-equilibrium quantities, such as fluctuations of work, exhibit critical scaling after a sudden quench in a closed system has remained elusive. Here, we take a novel approach to the problem by studying a quench across an impurity quantum critical point. By performing density matrix renormalization group computations on the two-impurity Kondo model, we are able to establish that the irreversible work produced in a quench exhibits finite-size scaling at quantum criticality. This scaling faithfully predicts the equilibrium critical exponents for the crossover length and the order parameter of the model, and, moreover, implies an exponent for the rescaled irreversible work. By connecting the irreversible work to the two-impurity spin correlation function, our findings can be tested experimentally.

  2. The critical thinking curriculum model

    NASA Astrophysics Data System (ADS)

    Robertson, William Haviland

    The Critical Thinking Curriculum Model (CTCM) utilizes a multidisciplinary approach that integrates effective learning and teaching practices with computer technology. The model is designed to be flexible within a curriculum, an example for teachers to follow, where they can plug in their own critical issue. This process engages students in collaborative research that can be shared in the classroom, across the country or around the globe. The CTCM features open-ended and collaborative activities that deal with current, real world issues which leaders are attempting to solve. As implemented in the Critical Issues Forum (CIF), an educational program administered by Los Alamos National Laboratory (LANL), the CTCM encompasses the political, social/cultural, economic, and scientific realms in the context of a current global issue. In this way, students realize the importance of their schooling by applying their efforts to an endeavor that ultimately will affect their future. This study measures student attitudes toward science and technology and the changes that result from immersion in the CTCM. It also assesses the differences in student learning in science content and problem solving for students involved in the CTCM. A sample of 24 students participated in classrooms at two separate high schools in New Mexico. The evaluation results were analyzed using SPSS in a MANOVA format in order to determine the significance of the between and within-subjects effects. A comparison ANOVA was done for each two-way MANOVA to see if the comparison groups were equal. Significant findings were validated using the Scheffe test in a Post Hoc analysis. Demographic information for the sample population was recorded and tracked, including self-assessments of computer use and availability. Overall, the results indicated that the CTCM did help to increase science content understanding and problem-solving skills for students, thereby positively effecting critical thinking. No matter if the

  3. Critical Success Factors for International Education Marketing.

    ERIC Educational Resources Information Center

    Mazzarol, Tim

    1998-01-01

    Reports a survey of 315 higher education and private secondary institutions in Australia, Canada, New Zealand, United Kingdom, and United States that investigated factors critical to success in international marketing of educational programs. Results suggest that two factor groups (reputation and resources, and possession of international…

  4. Critical Reflective Working Behaviour: A Survey Research.

    ERIC Educational Resources Information Center

    van Woerkom, Marianne; Nijhof, Wim J.; Nieuwenhuis, Loek F. M.

    2002-01-01

    Survey responses from 742 of 1,670 Dutch workers validated the following dimensions of critically reflective work behavior: learning from mistakes, vision sharing, challenging group-think, asking for feedback, experimentation, knowledge sharing, and awareness of employability. Individual self-efficacy had more impact than job/organizational…

  5. Modern Criticism and the Closet Drama Approach.

    ERIC Educational Resources Information Center

    Nardin, James T.

    1965-01-01

    Modern drama criticism is rebuked for taking the "closet drama approach" which reduces the theater to yet another type of philosophical and content-oriented literary genre. Group participation and discussion are suggested as means by which the student is encouraged to stage an imaginary performance leading to intelligibility and appreciation of…

  6. Critical Thinking and Diversity Experiences: A Connection

    ERIC Educational Resources Information Center

    Inoue, Yukiko

    2005-01-01

    Critical thinking is an important learning outcome for college students. A review of the literature shows that this skill is affected by a number of factors, including exposure to cultural diversity. The University of Guam (UOG) located in the western Pacific is multicultural and multilingual. Using data from focus groups, this study examined the…

  7. Critical Quantitative Study of Immigrant Students

    ERIC Educational Resources Information Center

    Conway, Katherine M.

    2014-01-01

    The author discusses the importance of critical quantitative research for studies of immigrant students, a large and growing group, whose higher education experience is crucial to the future of the United States. The author outlines some of the distinctions to be made among immigrant students and recommends areas of future inquiry.

  8. Access to Multiliteracies: A Critical Ethnography

    ERIC Educational Resources Information Center

    Mills, Kathy Ann

    2007-01-01

    This paper reports the key findings of a critical ethnography, which documented the enactment of the multiliteracies pedagogy in an Australian elementary school classroom. The multiliteracies pedagogy of the New London Group is a response to the emergence of multimodal literacies in contemporary contexts of increased cultural and linguistic…

  9. Translation as Literary Criticism.

    ERIC Educational Resources Information Center

    di Stefano, B. Follkart

    1982-01-01

    It is proposed that literary translation is intrinsically an act of literary criticism. This theory is illustrated by discussion of specific problems in translating Sartre's "La Nausee" and Leonard Forest's "Le pays de la Sagouine," especially the use of verb tense. (MSE)

  10. Conductive Critical Thinking

    ERIC Educational Resources Information Center

    Paetkau, Mark

    2007-01-01

    One of my goals as an instructor is to teach students critical thinking skills. This paper presents an example of a student-led discussion of heat conduction at the first-year level. Heat loss from a human head is calculated using conduction and radiation models. The results of these plausible (but wrong) models of heat transfer contradict what…

  11. Critical Incidents in Negotiation.

    ERIC Educational Resources Information Center

    American Association of School Administrators, Washington, DC.

    This report presents imaginary dialogues between a management team and an employee team and critiques the dialogues to emphasize the significance of situations and episodes that can hasten or hamper a settlement at the negotiation table. Three critical incidents are studied within each developmental phase of the negotiation process: (1) procedural…

  12. Criticizing the Role.

    ERIC Educational Resources Information Center

    Cohen, Arthur M.

    Critics of the community college are justified in challenging unsubstantiated statements about the institution by college spokespersons or in public relations releases disguised as institutional analyses. During the 1960's, for example, increasing enrollments were often cited as evidence of public support for community colleges--without reference…

  13. Creativity and Critical Thinking.

    ERIC Educational Resources Information Center

    Kollen, Patsy Phillips

    How to deal with the absence of creativity and critical thinking in the educational setting is discussed. All efforts to improve education will be futile if we don't take into account the absence of relationship among the participants and between the participants and the content of education. Relationship--i.e., connecting with others and with…

  14. SEMANTICS AND CRITICAL READING.

    ERIC Educational Resources Information Center

    FLANIGAN, MICHAEL C.

    PROFICIENCY IN CRITICAL READING CAN BE ACCELERATED BY MAKING STUDENTS AWARE OF VARIOUS SEMANTIC DEVICES THAT HELP CLARIFY MEANINGS AND PURPOSES. EXCERPTS FROM THE ARTICLE "TEEN-AGE CORRUPTION" FROM THE NINTH-GRADE SEMANTICS UNIT WRITTEN BY THE PROJECT ENGLISH DEMONSTRATION CENTER AT EUCLID, OHIO, ARE USED TO ILLUSTRATE HOW SEMANTICS RELATE TO…

  15. Audience, Style and Criticism

    ERIC Educational Resources Information Center

    Pimm, David; Sinclair, Nathalie

    2009-01-01

    The primary focus for this article involves aspects of professional mathematical writing and examines the possibility of a form of literary criticism in relation to it. By means of examples from contemporary style guides for academic articles in mathematics (AMS, MAA), as well as the writing of mathematicians (Hamilton, Dedekind) from earlier…

  16. Critical Thinking Concept Reconstructed

    ERIC Educational Resources Information Center

    Minter, Mary Kennedy

    2010-01-01

    This paper explores the proposition that teaching of critical thinking (CT) should include: (1) identifying and addressing the many environmental variables acting as barriers to our human thinking, i.e., an open system approach, and (2) utilizing the interrelatedness of the CT building blocks, i.e., creative thinking techniques, levels of…

  17. Replies to Criticisms

    ERIC Educational Resources Information Center

    Hamilton, James R.

    2009-01-01

    In this essay, Hamilton responds to criticisms of his book "The Art of Theater" (Malden, MA: Blackwell, 2007). Acknowledging that he expected that the central proposals in "The Art of Theater" would seem a little strange to philosophers, he reiterates his belief that the three general facts of any theatrical performance are its presentation, its…

  18. Critical Thinking and Learning

    ERIC Educational Resources Information Center

    Mason, Mark

    2007-01-01

    This paper introduces some of the debates in the field of critical thinking by highlighting differences among thinkers such as Siegel, Ennis, Paul, McPeck, and Martin, and poses some questions that arise from these debates. Does rationality transcend particular cultures, or are there different kinds of thinking, different styles of reasoning? What…

  19. Critical Practice: Teaching "Shakespeare."

    ERIC Educational Resources Information Center

    Mellor, Bronwyn; Patterson, Annette

    2000-01-01

    Describes how the authors taught their students to read "Hamlet" from a critical literacy perspective, analyzing how particular readings of texts and characters are constructed or produced; how they are determined by historical and cultural conventions; analyzing values that various readings support or challenge--rather than trying to get closer…

  20. Stateline: Critical Mass

    ERIC Educational Resources Information Center

    Christie, Kathy

    2005-01-01

    In Physics "critical mass" refers to the minimum amount of fissionable material required to sustain a chain reaction. The adoption of state education policy isn't often equated with this concept, but occasionally solutions and ideas seem to gather around a common problem. If the solution at hand is simple, easily understood, and strengthened with…

  1. Deconfined quantum critical points.

    PubMed

    Senthil, T; Vishwanath, Ashvin; Balents, Leon; Sachdev, Subir; Fisher, Matthew P A

    2004-03-01

    The theory of second-order phase transitions is one of the foundations of modern statistical mechanics and condensed-matter theory. A central concept is the observable order parameter, whose nonzero average value characterizes one or more phases. At large distances and long times, fluctuations of the order parameter(s) are described by a continuum field theory, and these dominate the physics near such phase transitions. We show that near second-order quantum phase transitions, subtle quantum interference effects can invalidate this paradigm, and we present a theory of quantum critical points in a variety of experimentally relevant two-dimensional antiferromagnets. The critical points separate phases characterized by conventional "confining" order parameters. Nevertheless, the critical theory contains an emergent gauge field and "deconfined" degrees of freedom associated with fractionalization of the order parameters. We propose that this paradigm for quantum criticality may be the key to resolving a number of experimental puzzles in correlated electron systems and offer a new perspective on the properties of complex materials.

  2. Light Touch Critical Friendship

    ERIC Educational Resources Information Center

    Swaffield, Sue

    2007-01-01

    Critical friendship is a flexible form of support for school colleagues and one that is increasingly being applied to different contexts, including the New Relationship with Schools and School Improvement Partners. The ESRC/TLRP "Learning How to Learn" (LHTL) project was interested in, among other things, the scaling up of innovation, and…

  3. Critical Skills Survey

    ERIC Educational Resources Information Center

    Education Digest: Essential Readings Condensed for Quick Review, 2010

    2010-01-01

    As the U.S. economy begins to show signs of improvement, executives say they need a workforce fully equipped with skills beyond just the basics of reading, writing, and arithmetic (the three Rs). Skills such as critical thinking and problem solving, communication, collaboration, and creativity and innovation (the four Cs) will become even more…

  4. Educational Criticism and Shamanism.

    ERIC Educational Resources Information Center

    Sevigny, Maurice J.

    1984-01-01

    Critiqued is the article, "Teacher as Shaman: An Educational Criticism," (Studies in Art Education, v25 n1), containing a case study of an art teacher who employs performance-based ritual to stimulate thinking about art's meaning and history. The problem that ethnographic researchers have conveying credibility when summarizing investigations is…

  5. Critical Education, Critical Pedagogies, Marxist Education in the United States

    ERIC Educational Resources Information Center

    Foley, Jean Ann; Morris, Doug; Gounari, Panayota; Agostinone-Wilson, Faith

    2015-01-01

    As critical pedagogy becomes more mainstream on the educational landscape in the United States, it is important to revisit the original tenets of critical pedagogy and explore their current manifestations. Since the beginning of "criticalism" from the theoretical/foundational work of the Frankfurt School of Critical Social Theory,…

  6. Group Work Publication-1991.

    ERIC Educational Resources Information Center

    Zimpfer, David G.

    1992-01-01

    Lists 21 new publications in group work, of which 9 are reviewed. Those discussed include publications on group counseling and psychotherapy, structured groups, support groups, psychodrama, and social group work. (Author/NB)

  7. Group Cohesion in Experiential Growth Groups

    ERIC Educational Resources Information Center

    Steen, Sam; Vasserman-Stokes, Elaina; Vannatta, Rachel

    2014-01-01

    This article explores the effect of web-based journaling on changes in group cohesion within experiential growth groups. Master's students were divided into 2 groups. Both used a web-based platform to journal after each session; however, only 1 of the groups was able to read each other's journals. Quantitative data collected before and…

  8. 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 liquid xenon, a heavy inert gas used in flash lamps and ion rocket engines, at its critical point. Resembling a tiny bit of window screen, the oscillator at the heart of CVX-2 will vibrate between two pairs of paddle-like electrodes. The slight bend in the shape of the mesh has no effect on the data. What counts are the mesh's displacement in the xenon fluid and the rate at which the displacement dampens. The unit shown here is encased in a small test cell and capped with a sapphire windown to contain the xenon at high pressure.

  9. Critical dynamics and decoherence

    SciTech Connect

    Damski, Bogdan; Quan, Haitao T; Zurek, Wojciech H

    2009-01-01

    We study dynamics of decoherence in a generic model where the environment is driven and undergoes a quantum phase transition. We model the environment by the Ising chain in the transverse field, and assume that the decohering system is a central spin-1/2. We found that when the environment is quenched slowly through the critical point, the decoherence factor of the central spin undergoes rapid decay that encodes the critical exponents of the environment. We also found that decoherence in a non-equilibrated, kink-contaminated, environment can be stronger than in a vacuum one. We derived a remarkably simple analytical expression that describes post-transition decoherence and predicts periodicities involving all system parameters. This research connects the fields of decoherence, quantum phase transitions, and Kibble-Zurek non-equilibrium dynamics.

  10. Critical branching neural networks.

    PubMed

    Kello, Christopher T

    2013-01-01

    It is now well-established that intrinsic variations in human neural and behavioral activity tend to exhibit scaling laws in their fluctuations and distributions. The meaning of these scaling laws is an ongoing matter of debate between isolable causes versus pervasive causes. A spiking neural network model is presented that self-tunes to critical branching and, in doing so, simulates observed scaling laws as pervasive to neural and behavioral activity. These scaling laws are related to neural and cognitive functions, in that critical branching is shown to yield spiking activity with maximal memory and encoding capacities when analyzed using reservoir computing techniques. The model is also shown to account for findings of pervasive 1/f scaling in speech and cued response behaviors that are difficult to explain by isolable causes. Issues and questions raised by the model and its results are discussed from the perspectives of physics, neuroscience, computer and information sciences, and psychological and cognitive sciences.

  11. Critical care in India.

    PubMed

    Udwadia, F E; Guntupalli, K K; Vidyasagar, D

    1997-04-01

    India is a vast democracy of nearly one billion people. Before the British rule ended in 1947, the life span of an Indian was a mere 21 years. Within a short span of 50 years, it increased to an impressive 63 years, largely due to public health measures initiated by the government. This created a pool of more than 300 million middle class Indians who could afford the benefits of modern and specialized care when needed. Critical care medicine, as practiced in the West, is still confined to large Metropolitan areas. A large pool of expatriate Indian physicians from all over the world are helping bridge the resource gap between the West and India by transfer of technology and providing appropriate training to physicians and paramedical personnel. This article describes the history and current status of development of critical care medicine in India. PMID:9107510

  12. Working with Cooperative Small Groups. Classroom Tips

    ERIC Educational Resources Information Center

    American Federation of Teachers (NJ), 2010

    2010-01-01

    Diversified small groups in the classroom provide a good opportunity for students to share information and ideas with each other. The research on cooperative small groups points out the benefits of these interactions and describes the process as a powerful forum for developing students' critical thinking and higher-order skills: (1) Cooperative…

  13. Team Development Versus T-Group Training.

    ERIC Educational Resources Information Center

    Woodman, Richard W.

    1980-01-01

    T-groups methodology plays an important role as an experiential learning approach both within and outside of organizational settings. An understanding of differences and similarities between T-group training and team development is critical for communication and for intelligent decisions concerning their utility in organizational development…

  14. Carahunge - A Critical Assessment

    NASA Astrophysics Data System (ADS)

    González-García, A. César

    Carahunge is a megalithic monument in southern Armenia that has often been acclaimed as the oldest observatory. The monument, composed of dozens of standing stones, has some perforated stones. The direction of the holes has been measured and their orientation is related to the sun, moon, and stars, obtaining a date for the construction of such devices. After a critical review of the methods and conclusions, these are shown as untenable.

  15. Criticality safety training

    SciTech Connect

    Woodruff, S.K.

    1997-06-01

    Criticality safety training is an important element of the Plutonium Facility safety program at Los Alamos National Laboratory. Training consists of student self-study handbooks and hands-on performance-based training in a mock-up laboratory containing gloveboxes, trolley conveyor system, and self-monitoring instruments. A 10-minute video tape and lecture was presented to describe how training in this area is conducted.

  16. Critical Path Web Site

    NASA Technical Reports Server (NTRS)

    Robinson, Judith L.; Charles, John B.; Rummel, John A. (Technical Monitor)

    2000-01-01

    Approximately three years ago, the Agency's lead center for the human elements of spaceflight (the Johnson Space Center), along with the National Biomedical Research Institute (NSBRI) (which has the lead role in developing countermeasures) initiated an activity to identify the most critical risks confronting extended human spaceflight. Two salient factors influenced this activity: first, what information is needed to enable a "go/no go" decision to embark on extended human spaceflight missions; and second, what knowledge and capabilities are needed to address known and potential health, safety and performance risks associated with such missions. A unique approach was used to first define and assess those risks, and then to prioritize them. This activity was called the Critical Path Roadmap (CPR) and it represents an opportunity to develop and implement a focused and evolving program of research and technology designed from a "risk reduction" perspective to prevent or minimize the risks to humans exposed to the space environment. The Critical Path Roadmap provides the foundation needed to ensure that human spaceflight, now and in the future, is as safe, productive and healthy as possible (within the constraints imposed on any particular mission) regardless of mission duration or destination. As a tool, the Critical Path Roadmap enables the decision maker to select from among the demonstrated or potential risks those that are to be mitigated, and the completeness of that mitigation. The primary audience for the CPR Web Site is the members of the scientific community who are interested in the research and technology efforts required for ensuring safe and productive human spaceflight. They may already be informed about the various space life sciences research programs or they may be newcomers. Providing the CPR content to potential investigators increases the probability of their delivering effective risk mitigations. Others who will use the CPR Web Site and its

  17. Critical Path Web Site

    NASA Technical Reports Server (NTRS)

    Robinson, Judith L.; Charles, John B.; Rummel, John A. (Technical Monitor)

    2000-01-01

    Approximately three years ago, the Agency's lead center for the human elements of spaceflight (the Johnson Space Center), along with the National Biomedical Research Institute (NSBRI) (which has the lead role in developing countermeasures) initiated an activity to identify the most critical risks confronting extended human spaceflight. Two salient factors influenced this activity: first, what information is needed to enable a "go/no go" decision to embark on extended human spaceflight missions; and second, what knowledge and capabilities are needed to address known and potential health, safety and performance risks associated with such missions. A unique approach was used to first define and assess those risks, and then to prioritize them. This activity was called the Critical Path Roadmap (CPR) and it represents an opportunity to develop and implement a focused and evolving program of research and technology designed from a "risk reduction" perspective to prevent or minimize the risks to humans exposed to the space environment. The Critical Path Roadmap provides the foundation needed to ensure that human spaceflight, now and in the future, is as safe, productive and healthy as possible (within the constraints imposed on any particular mission) regardless of mission duration or destination. As a tool, the Critical Path Roadmap enables the decisionmaker to select from among the demonstrated or potential risks those that are to be mitigated, and the completeness of that mitigation. The primary audience for the CPR Web Site is the members of the scientific community who are interested in the research and technology efforts required for ensuring safe and productive human spaceflight. They may already be informed about the various space life sciences research programs or they may be newcomers. Providing the CPR content to potential investigators increases the probability of their delivering effective risk mitigations. Others who will use the CPR Web Site and its content

  18. Challenges in Critical Language Teaching

    ERIC Educational Resources Information Center

    Pessoa, Rosane Rocha; de Urzeda Freitas, Marco Tulio

    2012-01-01

    This article is based on the conception of language teaching as a liberatory practice. Drawing on some principles of critical pedagogy (Ellsworth, 1992; Freire, 2005; hooks, 1994; Norton & Toohey, 2004), critical applied linguistics (Pennycook, 1990, 2001), critical language teaching (Ferreira, 2006; Pennycook, 1999), and critical language teacher…

  19. Morphogenesis at criticality?

    NASA Astrophysics Data System (ADS)

    Krotov, Dmitry; Dubuis, Julien; Wieschaus, Eric; Gregor, Thomas; Bialek, William

    2013-03-01

    Embryonic development of many multicellular organisms begins with the generation of spatially varying patterns of morphogens that encode the body plan of the future organism. We study the spatial pattern formed by the gap gene proteins in the early fruit fly embryo, which is anchored by ``crossing points'' between expression levels of different genes; these are thought to result from mutual repression. We explore a broad class of models for such interacting genes and show that the parameters implied implied by recent quantitative measurements are non-generic, but rather tuned to certain values, so that the entire gap gene network operates close to the critical surface in its phase diagram. We develop a mean field description of this system as well as derive signatures of critical behavior in the structure of expression noise. One such signature is that fluctuations are dominated by a single ``massless'' mode, so that fluctuations of expression levels of different genes are highly correlated/anticorrelated. We find a surprisingly high degree of anticorrelation in the real experimental data. These results suggest an interesting possibility that the network of genes responsible for development is operating near criticality.

  20. A primer for criticality calculations with DANTSYS

    SciTech Connect

    Busch, R.D.

    1997-08-01

    With the closure of many experimental facilities, the nuclear safety analyst has to rely on computer calculations to identify safe limits for the handling and storage of fissile materials. Although deterministic methods often do not provide exact models of a system, a substantial amount of reliable information on nuclear systems can be obtained using these methods if the user understands their limitations. To guide criticality specialists in this area, the Nuclear Criticality Safety Group at the University of New Mexico (UNM) in cooperation with the Radiation Transport Group at Los Alamos National Laboratory (LANL) has designed a primer to help the analyst understand and use the DANTSYS deterministic transport code for nuclear criticality safety analyses. DANTSYS is the new name of the group of codes formerly known as: ONEDANT, TWODANT, TWOHEX, TWOGQ, and THREEDANT. The primer is designed to teach bu example, with each example illustrating two or three DANTSYS features useful in criticality analyses. Starting with a Quickstart chapter, the primer gives an overview of the basic requirements for DANTSYS input and allows the user to quickly run a simple criticality problem with DANTSYS. Each chapter has a list of basic objectives at the beginning identifying the goal of the chapter and the individual DANTSYS features covered in detail in the chapter example problems. On completion of the primer, it is expected that the user will be comfortable doing criticality calculations with DANTSYS and can handle 60--80% of the situations that normally arise in a facility. The primary provides a set of input files that can be selective modified by the user to fit each particular problem.

  1. Generic Critical Thinking Infusion and Course Content Learning in Introductory Psychology

    ERIC Educational Resources Information Center

    Solon, Tom

    2007-01-01

    One group of introductory psychology students received a moderate infusion of generic critical thinking material. The other group did not. Otherwise both groups had the same course content, and took the same pretests and posttests of their critical thinking ability and their knowledge of psychology. The experimental group improved its critical…

  2. CRITICALITY HAZOP EFFICIENTLY EVALUATING HAZARDS OF NEW OR REVISED CRITICALITY SAFETY EVALUATIONS

    SciTech Connect

    CARSON DM

    2008-04-15

    The 'Criticality HazOp' technique, as developed at Hanford's Plutonium Finishing Plant (PFP), has allowed for efficiencies enabling shortening of the time necessary to complete new or revised criticality safety evaluation reports (CSERs). For example, in the last half of 2007 at PFP, CSER revisions undergoing the 'Criticality HazOp' process were completed at a higher rate than previously achievable. The efficiencies gained through use of the 'Criticality HazOp' process come from the preliminary narrowing of potential scenarios for the Criticality analyst to fully evaluate in preparation of the new or revised CSER, and from the use of a systematized 'Criticality HazOp' group assessment of the relevant conditions to show which few parameter/condition/deviation combinations actually require analytical effort. The 'Criticality HazOp' has not only provided efficiencies of time, but has brought to criticality safety evaluation revisions the benefits of a structured hazard evaluation method and the enhanced insight that may be gained from direct involvement of a team in the process. In addition, involved personnel have gained a higher degree of confidence and understanding of the resulting CSER product.

  3. Implementation and evaluation of critical thinking strategies to enhance critical thinking skills in Middle Eastern nurses.

    PubMed

    Simpson, Elaine; Courtney, Mary

    2008-12-01

    The purpose of this study was to develop, implement and evaluate critical thinking strategies to enhance critical thinking skills in Middle Eastern nurses. Critical thinking strategies such as questioning, debate, role play and small group activity were developed and used in a professional development programme, which was trialled on a sample of Middle Eastern nurses (n = 20), to promote critical thinking skills, encourage problem solving, development of clinical judgment making and care prioritization in order to improve patient care and outcomes. Classroom learning was transformed from memorization to interaction and active participation. The intervention programme was successful in developing critical thinking skills in both the nurse educators and student nurses in this programme. This programme successfully integrated critical thinking strategies into a Middle Eastern nursing curriculum. Recommendations are as follows: (1) utilize evidence-based practice and stem questions to encourage the formulation of critical thinking questions; (2) support the needs of nurse educators for them to effectively implement teaching strategies to foster critical thinking skills; and (3) adopt creative approaches to (i) transform students into interactive participants and (ii) open students' minds and stimulate higher-level thinking and problem-solving abilities.

  4. Critical incident monitoring in anaesthesia.

    PubMed

    Choy, Y C

    2006-12-01

    far from clear and very difficult to study. Efforts to do so have tended to rely on incident reporting, the only practical approach when funding is limited. The heterogeneity of critically ill patients as a group means that huge study populations would be required if other research techniques were to be used. In the era of evidence-based medicine, anaesthetists are looking for alternative evidence-based solutions to problems that we have accepted traditionally when we cannot quantify for good practical reasons. In the quest for patient safety, investment should be made in reliable audit, detection and reporting systems. The growing recognition that human error usually result from a failure of a system rather than an individual should be fostered to allow more lessons to be learnt, an approach that has been successful in other, safety-critical industries. New technology has a great deal to offer and investment is warranted in novel fail-safe drug administration systems. Last but not the least the importance of simple and sensible changes and better education should be remembered. PMID:17623959

  5. Criticality validation for burnup credit using recycle Pu criticals

    SciTech Connect

    Fuentes, E.; Lancaster, D.

    1997-04-01

    A set of 23 additional critical experiments were analyzed to provide additional input to the criticality validation portion of spent fuel cask analysis. The results of this analyses were combined with the previously analyzed criticals to determine the upper safety limit on k{sub eff}. The combined set of criticals can be used used for criticality validation for burnup credit, and are better suited for the range of isotopics in spent nuclear fuels. A trend observed in the analysis was that the calculated k{sub eff} deviates from the criticals in the positive direction, implying that increased burnup results in increased safety margin. 6 refs., 2 figs., 1 tab.

  6. The Effect of Three Computer Conferencing Designs on Critical Thinking Skills of Nursing Students

    ERIC Educational Resources Information Center

    Duphorne, Patsy L.; Gunawardena, Charlotte N.

    2005-01-01

    A study of university nursing students tested the effect of computer conference designs and advance organizers on critical thinking skills. Critical thinking, although not significantly different between three conference groups, was evident for groups in all three conference designs. Those conferences designed to facilitate critical inquiry showed…

  7. Interagency mechanical operations group numerical systems group

    SciTech Connect

    1997-09-01

    This report consists of the minutes of the May 20-21, 1971 meeting of the Interagency Mechanical Operations Group (IMOG) Numerical Systems Group. This group looks at issues related to numerical control in the machining industry. Items discussed related to the use of CAD and CAM, EIA standards, data links, and numerical control.

  8. Group Dynamic Processes in Email Groups

    ERIC Educational Resources Information Center

    Alpay, Esat

    2005-01-01

    Discussion is given on the relevance of group dynamic processes in promoting decision-making in email discussion groups. General theories on social facilitation and social loafing are considered in the context of email groups, as well as the applicability of psychodynamic and interaction-based models. It is argued that such theories may indeed…

  9. Facilitating Reminiscence Groups: Perceptions of Group Leaders

    ERIC Educational Resources Information Center

    Christensen, Teresa M.; Hulse-Killacky, Diana; Salgado, Roy A.; Thornton, Mark D.; Miller, Jason L.

    2006-01-01

    This article presents the results of a two-year qualitative investigation in which group leaders provided their perceptions of the process of facilitating reminiscence groups with elderly persons in a residential care facility. Group Culture emerged as the dominant construct. Findings from this study can serve guide leaders who are interested in…

  10. Weightless experiments to probe universality of fluid critical behavior.

    PubMed

    Lecoutre, C; Guillaument, R; Marre, S; Garrabos, Y; Beysens, D; Hahn, I

    2015-06-01

    Near the critical point of fluids, critical opalescence results in light attenuation, or turbidity increase, that can be used to probe the universality of critical behavior. Turbidity measurements in SF6 under weightlessness conditions on board the International Space Station are performed to appraise such behavior in terms of both temperature and density distances from the critical point. Data are obtained in a temperature range, far (1 K) from and extremely close (a few μK) to the phase transition, unattainable from previous experiments on Earth. Data are analyzed with renormalization-group matching classical-to-critical crossover models of the universal equation of state. It results that the data in the unexplored region, which is a minute deviant from the critical density value, still show adverse effects for testing the true asymptotic nature of the critical point phenomena.

  11. Weightless experiments to probe universality of fluid critical behavior

    NASA Astrophysics Data System (ADS)

    Lecoutre, C.; Guillaument, R.; Marre, S.; Garrabos, Y.; Beysens, D.; Hahn, I.

    2015-06-01

    Near the critical point of fluids, critical opalescence results in light attenuation, or turbidity increase, that can be used to probe the universality of critical behavior. Turbidity measurements in SF6 under weightlessness conditions on board the International Space Station are performed to appraise such behavior in terms of both temperature and density distances from the critical point. Data are obtained in a temperature range, far (1 K) from and extremely close (a few μ K ) to the phase transition, unattainable from previous experiments on Earth. Data are analyzed with renormalization-group matching classical-to-critical crossover models of the universal equation of state. It results that the data in the unexplored region, which is a minute deviant from the critical density value, still show adverse effects for testing the true asymptotic nature of the critical point phenomena.

  12. Concepts and methods for describing critical phenomena in fluids

    NASA Technical Reports Server (NTRS)

    Sengers, J. V.; Sengers, J. M. H. L.

    1977-01-01

    The predictions of theoretical models for a critical-point phase transistion in fluids, namely the classical equation with third-degree critical isotherm, that with fifth-degree critical isotherm, and the lattice gas, are reviewed. The renormalization group theory of critical phenomena and the hypothesis of universality of critical behavior supported by this theory are discussed as well as the nature of gravity effects and how they affect cricital-region experimentation in fluids. The behavior of the thermodynamic properties and the correlation function is formulated in terms of scaling laws. The predictions of these scaling laws and of the hypothesis of universality of critical behavior are compared with experimental data for one-component fluids and it is indicated how the methods can be extended to describe critical phenomena in fluid mixtures.

  13. Safety Critical Mechanisms

    NASA Technical Reports Server (NTRS)

    Robertson, Brandan

    2008-01-01

    Spaceflight mechanisms have a reputation for being difficult to develop and operate successfully. This reputation is well earned. Many circumstances conspire to make this so: the environments in which the mechanisms are used are extremely severe, there is usually limited or no maintenance opportunity available during operation due to this environment, the environments are difficult to replicate accurately on the ground, the expense of the mechanism development makes it impractical to build and test many units for long periods of time before use, mechanisms tend to be highly specialized and not prone to interchangeability or off-the-shelf use, they can generate and store a lot of energy, and the nature of mechanisms themselves, as a combination of structures, electronics, etc. designed to accomplish specific dynamic performance, makes them very complex and subject to many unpredictable interactions of many types. In addition to their complexities, mechanism are often counted upon to provide critical vehicle functions that can result in catastrophic events should the functions not be performed. It is for this reason that mechanisms are frequently subjected to special scrutiny in safety processes. However, a failure tolerant approach, along with good design and development practices and detailed design reviews, can be developed to allow such notoriously troublesome mechanisms to be utilized confidently in safety-critical applications.

  14. Rethinking Critical Adsorption

    NASA Astrophysics Data System (ADS)

    Franck, Carl; Peach, Sarah; Polak, Robert D.

    1996-03-01

    Recent reflectivity experiments on near-critical mixtures of carbon disulfide and nitromethane contained in glass cells footnote Niraj S. Desai, Sarah Peach, and Carl Franck, Phys. Rev. E 52, 4129 (1995) have shown that preferential adsorption of one liquid component onto the wall can be controlled by chemical modification of the glass. The glass was treated with varying amounts of hexamethyldisilazane to decrease surface polarity and therefore enhance the adsorption of carbon disulfide in a surprisingly continuous way. The effect of the glass wall on the local liquid composition can be described by two different scaling hypotheses: using a short range field on the liquid closest to the wall, or pinning the amplitude of the order parameter at the surface. We have found that only the second approach is consistent with the experimental data, although this is difficult to reconcile with observed wetting critical phenomena. We also have reexamined the issue of substrate inhomogeneity and conclude that the substrates were indeed homogeneous on relevant length scales. Supported by the NSF under DMR-9320910 and the central facilities of the Materials Science Center at Cornell University.

  15. Design of Critical Components

    NASA Technical Reports Server (NTRS)

    Hendricks, Robert C.; Zaretsky, Erwin V.

    2001-01-01

    Critical component design is based on minimizing product failures that results in loss of life. Potential catastrophic failures are reduced to secondary failures where components removed for cause or operating time in the system. Issues of liability and cost of component removal become of paramount importance. Deterministic design with factors of safety and probabilistic design address but lack the essential characteristics for the design of critical components. In deterministic design and fabrication there are heuristic rules and safety factors developed over time for large sets of structural/material components. These factors did not come without cost. Many designs failed and many rules (codes) have standing committees to oversee their proper usage and enforcement. In probabilistic design, not only are failures a given, the failures are calculated; an element of risk is assumed based on empirical failure data for large classes of component operations. Failure of a class of components can be predicted, yet one can not predict when a specific component will fail. The analogy is to the life insurance industry where very careful statistics are book-kept on classes of individuals. For a specific class, life span can be predicted within statistical limits, yet life-span of a specific element of that class can not be predicted.

  16. Competing Priorities: Singaporean Teachers' Perspectives on Critical Literacy

    ERIC Educational Resources Information Center

    Curdt-Christiansen, Xiao Lan

    2010-01-01

    This paper explores a group of Singaporean English language teachers' knowledge and beliefs about critical literacy as well as their perspectives on how best to teach literacy and critical literacy in Singapore schools. A face-to-face survey was conducted among 58 English language teachers by using open-ended questions. The survey covered various…

  17. Connecting Autoethnography with Service Learning: A Critical Communication Pedagogical Approach

    ERIC Educational Resources Information Center

    Kahl, David H., Jr.

    2010-01-01

    This article describes a project that encourages the development of a critical-pedagogical perspective in an undergraduate small group communication class. The project provides a transition from ideology to practice by combining activities that have been connected to critical communication pedagogy--service learning and autoethnography. The…

  18. Activating Pre-Service Mathematics Teachers' Critical Thinking

    ERIC Educational Resources Information Center

    Applebaum, Mark

    2015-01-01

    Teachers' critical thinking skills are essential for fostering the development of the same skills in their students. To demonstrate how teachers' ability to examine solutions critically can be developed and supported, we analyse a classroom activity performed by a group of pre-service secondary school mathematics teachers (N = 37) who were asked:…

  19. Surveys explore critical governance relationship.

    PubMed

    Grant, M K

    1987-01-01

    The transition in religious-sponsored health care from a ministry of direct service to one of governance has generated serious and penetrating questions, analyses, and retrenchment. Emphasis on and demand for value-laden leadership development programs are growing at the same time that sponsoring groups are becoming more actively involved in the governance and oversight of their corporate ministries. Two recent Catholic Health Association (CHA) studies focused on the critical governance relationship between the sponsoring group and its incorporated ministries. The first study asked religious institutes and dioceses that were sponsors of CHA member health care freestanding facilities and systems to describe their current governance structure. The second study represented an initial attempt to identify qualitative components of effective governance or sponsorship and asked 19 major superiors and system chief executive officers (CEOs) to characterize an ideal relationship between sponsor and ministry. The studies' findings included the following: In freestanding facilities, lay-religious governing boards have all but replaced the all-sponsor and all-lay advisory boards of the past. Trustee orientation, development, and evaluation were not equally stressed in the three groups surveyed, with trustee evaluation programs lagging behind in all three. Major superiors and CEOs had remarkably similar expectations relating to accountability for mission, relationships between sponsor and corporation, communication, and leadership development. Both major superiors and CEOs looked for greater collaboration in defining roles, translating mission into "business plan", and developing formation programs for leadership. Major superiors' emphasized simplicity of life-style, whereas the CEOs stressed stable commitment to corporate ministry.

  20. Boundary quantum critical phenomena with entanglement renormalization

    SciTech Connect

    Evenbly, G.; Pfeifer, R. N. C.; Tagliacozzo, L.; McCulloch, I. P.; Vidal, G.; Pico, V.; Iblisdir, S.

    2010-10-15

    We propose the use of entanglement renormalization techniques to study boundary critical phenomena on a lattice system. The multiscale entanglement renormalization ansatz (MERA), in its scale invariant version, offers a very compact approximation to quantum critical ground states. Here we show that, by adding a boundary to the MERA, an accurate approximation to the ground state of a semi-infinite critical chain with an open boundary is obtained, from which one can extract boundary scaling operators and their scaling dimensions. As in Wilson's renormalization-group formulation of the Kondo problem, our construction produces, as a side result, an effective chain displaying explicit separation of energy scales. We present benchmark results for the quantum Ising and quantum XX models with free and fixed boundary conditions.

  1. The IARC monographs: critics and controversy.

    PubMed

    Samet, Jonathan M

    2015-07-01

    The monograph program of the International Agency for Research on Cancer (IARC), which relies on the efforts of volunteer Working Groups, uses a transparent approach to evaluate the carcinogenicity of agents for which scoping has determined that there is sufficient evidence to warrant a review. Because of the potentially powerful implications of the conclusions of the monographs and the sometimes challenging nature of the evidence reviewed, the monographs and the IARC process have been criticized from time to time. This commentary describes the IARC monograph process and addresses recent criticisms of the program, drawing on a recent defense of the program authored by 124 researchers. These authors concluded that the IARC processes are robust and transparent and not flawed and biased as suggested by some critics. PMID:25943987

  2. Lawrence Livermore plutonium button critical experiment benchmark

    SciTech Connect

    Trumble, E.F.; Justice, J.B.; Frost, R.L.

    1994-12-31

    The end of the Cold War and the subsequent weapons reductions have led to an increased need for the safe storage of large amounts of highly enriched plutonium. In support of code validation required to address this need, a set of critical experiments involving arrays of weapons-grade plutonium metal that were performed at the Lawrence Livermore National Laboratory (LLNL) in the late 1960s has been revisited. Although these experiments are well documented, discrepancies and omissions have been found in the earlier reports. Many of these have been resolved in the current work, and these data have been compiled into benchmark descriptions. In addition, a computational verification has been performed on the benchmarks using multiple computer codes. These benchmark descriptions are also being made available to the US Department of Energy (DOE)-sponsored Nuclear Criticality Safety Benchmark Evaluation Working Group for dissemination in the DOE Handbook on Evaluated Criticality Safety Benchmark Experiments.

  3. Critical Literature Pedagogy: Teaching Canonical Literature for Critical Literacy

    ERIC Educational Resources Information Center

    Borsheim-Black, Carlin; Macaluso, Michael; Petrone, Robert

    2014-01-01

    This article introduces Critical Literature Pedagogy (CLP), a pedagogical framework for applying goals of critical literacy within the context of teaching canonical literature. Critical literacies encompass skills and dispositions to understand, question, and critique ideological messages of texts; because canonical literature is often…

  4. The Moral Imperative of Criticism

    ERIC Educational Resources Information Center

    Hillbruner, Anthony

    1975-01-01

    Elaborates on the ethical responsibility of the rhetorical critic and teacher. The role that moral values play in the criticism process are examined in the literature, history and philosophy disciplines. (MH)

  5. Creative critical-thinking strategies.

    PubMed

    Chubinski, S

    1996-01-01

    Are you looking for strategies to teach critical thinking? The author presents a variety of quick, creative strategies to facilitate teaching critical-thinking skills. These strategies engage students in their learning and are adaptable to any nursing course.

  6. Radiation Critical Readiness Review

    NASA Technical Reports Server (NTRS)

    Misek, William

    2010-01-01

    This slide presentation reviews the radiation preparedness and radiation monitors on the International Space Station (ISS). It includes information on the Tissue Equivalent Proportional Counter (TEPC), Radiation Area Monitors, Extra-Vehicular Charged Particle Directional Spectrometer (EV-CPDS), and the space radiation analysis group.

  7. Critical Density Interaction Studies

    SciTech Connect

    Young, P; Baldis, H A; Cheung, P; Rozmus, W; Kruer, W; Wilks, S; Crowley, S; Mori, W; Hansen, C

    2001-02-14

    Experiments have been performed to study the propagation of intense laser pulses to high plasma densities. The issue of self-focusing and filamentation of the laser pulse as well as developing predictive capability of absorption processes and x-ray conversion efficiencies is important for numerous programs at the Laboratory, particularly Laser Program (Fast Ignitor and direct-drive ICF) and D&NT (radiography, high energy backlighters and laser cutting). Processes such as resonance absorption, profile modification, linear mode conversion, filamentation and stimulated Brillouin scattering can occur near the critical density and can have important effects on the coupling of laser light to solid targets. A combination of experiments have been used to study the propagation of laser light to high plasma densities and the interaction physics of intense laser pulses with solid targets. Nonparaxial fluid codes to study nonstationary behavior of filamentation and stimulated Brillouin scattering at high densities have also been developed as part of this project.

  8. Critical Infrastructure Modeling System

    2004-10-01

    The Critical Infrastructure Modeling System (CIMS) is a 3D modeling and simulation environment designed to assist users in the analysis of dependencies within individual infrastructure and also interdependencies between multiple infrastructures. Through visual cuing and textual displays, a use can evaluate the effect of system perturbation and identify the emergent patterns that evolve. These patterns include possible outage areas from a loss of power, denial of service or access, and disruption of operations. Method ofmore » Solution: CIMS allows the user to model a system, create an overlay of information, and create 3D representative images to illustrate key infrastructure elements. A geo-referenced scene, satellite, aerial images or technical drawings can be incorporated into the scene. Scenarios of events can be scripted, and the user can also interact during run time to alter system characteristics. CIMS operates as a discrete event simulation engine feeding a 3D visualization.« less

  9. Actuating critical care therapeutics.

    PubMed

    Stone, David J; Csete, Marie

    2016-10-01

    Viewing the intensive care unit (ICU) as a control system with inputs (patients) and outputs (outcomes), we focus on actuation (therapies) of the system and how to enhance our understanding of status of patients and their trajectory in the ICU. To incorporate the results of these analytics meaningfully, we feel that a reassessment of predictive scoring systems and of ways to optimally characterize and display the patient's "state space" to clinicians is important. Advances in sensing (diagnostics) and computation have not yet led to significantly better actuation, and so we focus on ways that data can be used to improve actuation in the ICU, in particular by following therapeutic burden along with disease severity. This article is meant to encourage discussion about how the critical care community can best deal with the data they see each day, and prepare for recommendations that will inevitably arise from application of major federal and state initiatives in big data analytics and precision medicine.

  10. Critical CRBR core pressure

    SciTech Connect

    Ju, F.D.

    1980-06-01

    The conditions are detailed under which gas pressure will cause or initiate failure in the structural containment of the fuel core. The Clinch River Breeder Reactor Plant is the prototype structure. Two general classes of problems have been studied, representing two entirely distinct configurations of containment failure. The first model determines the minimum pressure to lift a portion or the entire core from its containment. The second model estimates the critical pressure above which the fuel rods interior to the hexagonal fuel can warp, leading to blockage of the gas passages. Such blockage might cause further buildup of the gas pressure to a level causing the failure of the fuel rod containment in the hexagonal fuel container.

  11. Criticality's Affective Entanglements: Rethinking Emotion and Critical Thinking in Higher Education

    ERIC Educational Resources Information Center

    Danvers, Emily Clair

    2016-01-01

    Critical thinking is often understood as a set of tangible, transferrable and measurable skills and competencies. Yet, it is also an intensely affective experience that is complex, contingent and contextualised. Using interview, focus group and observation data conducted with 15 first-year undergraduate social science students at a UK…

  12. Critical Bifocality and Circuits of Privilege: Expanding Critical Ethnographic Theory and Design

    ERIC Educational Resources Information Center

    Weis, Lois; Fine, Michelle

    2012-01-01

    In this article, Lois Weis and Michelle Fine introduce critical bifocality as a way to render visible the relations between groups to structures of power, to social policies, to history, and to large sociopolitical formations. In this collaboration, the authors draw upon ethnographic examples highlighting the macro-level structural dynamics…

  13. Critical loads of nitrogen deposition and critical levels of atmospheric ammonia for mediterranean evergreen woodlands

    NASA Astrophysics Data System (ADS)

    Pinho, P.; Theobald, M. R.; Dias, T.; Tang, Y. S.; Cruz, C.; Martins-Loução, M. A.; Máguas, C.; Sutton, M.; Branquinho, C.

    2011-11-01

    Nitrogen (N) has emerged in recent years as a key factor associated with global changes, with impacts on biodiversity, ecosystems functioning and human health. In order to ameliorate the effects of excessive N, safety thresholds have been established, such as critical loads (deposition fluxes) and levels (concentrations). For Mediterranean ecosystems, few studies have been carried out to assess these parameters. Our objective was therefore to determine the critical loads of N deposition and long-term critical levels of atmospheric ammonia for Mediterranean evergreen woodlands. For that we have considered changes in epiphytic lichen communities, which have been shown to be one of the most sensitive to excessive N. Based on a classification of lichen species according to their tolerance to N we grouped species into response functional groups, which we used as a tool to determine the critical loads and levels. This was done under Mediterranean climate, in evergreen cork-oak woodlands, by sampling lichen functional diversity and annual atmospheric ammonia concentrations and modelling N deposition downwind from a reduced N source (a cattle barn). By modelling the highly significant relationship between lichen functional groups and N deposition, the critical load was estimated to be below 26 kg (N) ha-1 yr-1, which is within the upper range established for other semi-natural ecosystems. By modelling the highly significant relationship of lichen functional groups with annual atmospheric ammonia concentration, the critical level was estimated to be below 1.9 μg m-3, in agreement with recent studies for other ecosystems. Taking into account the high sensitivity of lichen communities to excessive N, these values should be taken into account in policies that aim at protecting Mediterranean woodlands from the initial effects of excessive N.

  14. Against the Bureaucratization of Criticism.

    ERIC Educational Resources Information Center

    Nothstine, William L.; Copeland, Gary A.

    The proliferation of critics and critical approaches has produced a trend toward fragmentation and isolation among the practitioners involved. A suggestive counter-trend indicates that there is intense curiosity among critics to watch colleagues encounter texts, grapple with the preliminary questions of stance and method, and share the experience…

  15. A Critically Reflective Social Studies?

    ERIC Educational Resources Information Center

    Clarke, Marge

    1990-01-01

    Examines social studies in the twenty-first century from a critical theory perspective. Traces critical reflection's origins from Marxist educational theories to Jurgen Habermas's critical theory. Highlights Fred Newmann's curricular model, "Education for Citizen Action," for developing competent action in public affairs. Advocates infusing…

  16. Word Recognition and Critical Reading.

    ERIC Educational Resources Information Center

    Groff, Patrick

    1991-01-01

    This article discusses the distinctions between literal and critical reading and explains the role that word recognition ability plays in critical reading behavior. It concludes that correct word recognition provides the raw material on which higher order critical reading is based. (DB)

  17. Critical Quantitative Inquiry in Context

    ERIC Educational Resources Information Center

    Stage, Frances K.; Wells, Ryan S.

    2014-01-01

    This chapter briefly traces the development of the concept of critical quantitative inquiry, provides an expanded conceptualization of the tasks of critical quantitative research, offers theoretical explanation and justification for critical research using quantitative methods, and previews the work of quantitative criticalists presented in this…

  18. What Is Critical about Sociology?

    ERIC Educational Resources Information Center

    Buechler, Steven

    2008-01-01

    Critical thinking is often presented as a generic technique. This article develops an alternative that links critique more closely to the sociological perspective. I suggest three answers to the above question: that the sociological perspective is critical for comprehending complex issues, that all sociology is implicitly critical by virtue of its…

  19. The Tracking and Ability Grouping Debate. Volume 2, Number 8.

    ERIC Educational Resources Information Center

    Loveless, Tom

    Tracking and ability grouping are common practices that are often harshly criticized. Both practices group students of similar achievement levels for instruction, but they differ in how this task is accomplished. Elementary schools typically use ability grouping in reading instruction, with instruction targeted to the reading level of each group.…

  20. Designing and Assessing Productive Group Work in Secondary Schools

    ERIC Educational Resources Information Center

    Vaca, Javier; Lapp, Diane; Fisher, Douglas

    2011-01-01

    A history teacher examines what is successful and not successful in group work in his high school classroom and gives concrete suggestions for improving group practice. Topics discussed include preparing students for group work, supporting collaboration, inviting critical analysis, and assessing both group and individual performance. (Contains 2…

  1. Results from 2010 Caliban Criticality Dosimetry Intercomparison

    SciTech Connect

    Veinot, K. G.

    2011-10-12

    The external dosimetry program participated in a criticality dosimetry intercomparison conducted at the Caliban facility in Valduc, France in 2010. Representatives from the dosimetry and instrumentation groups were present during testing which included irradiations of whole-body beta/gamma (HBGT) and neutron thermoluminescent dosimeters (TLDs), a fixed nuclear accident dosimeter (FNAD), electronic alarming dosimeters, and a humanoid phantom filled with reference man concentrations of sodium. This report reviews the testing procedures, preparations, irradiations, and presents results of the tests.

  2. The Brain: What is Critical About It?

    NASA Astrophysics Data System (ADS)

    Chialvo, Dante R.; Balenzuela, Pablo; Fraiman, Daniel

    2008-07-01

    We review the recent proposal that the most fascinating brain properties are related to the fact that it always stays close to a second order phase transition. In such conditions, the collective of neuronal groups can reliably generate robust and flexible behavior, because it is known that at the critical point there is the largest abundance of metastable states to choose from. Here we review the motivation, arguments and recent results, as well as further implications of this view of the functioning brain.

  3. Better Field Instruction by Using Jigsaw Groups

    NASA Astrophysics Data System (ADS)

    Sammons, J. I.; Murray, D. P.

    2006-12-01

    Do any of these sound familiar? Most of my students do well at field stops, but there are always the few at the back. I'd like to guest speak at the local High School, but the students have too little background. I wish I could spark the interest of my introductory classes. Jigsaw is the solution to these problems. This easy-to-apply technique puts students in the driver's seat. They make the inferences-they own the discovery. You'll see that "A-ha!" as though it were a first time event. Jigsaw brings new excitement to familiar activities for every student in your class, even that guy in the back. Best of all, the technique does not depend on the style or force of personality of the instructor. It is easy to learn and suitable for use by Teaching Assistants. Here's how it works: 1. Identify the critical concepts necessary for a full understanding of the field stop or activity. 2. Divide your class into Expert Groups. The members of each Expert Group will master one of these critical concepts. 3.Dissolve the Expert Groups. Divide your class into new Jigsaw Groups to address the field stop or activity. Each Jigsaw Group includes members from each Expert Group. Like pieces of a puzzle, each Jigsaw Group member brings a critical piece to the problem. This talk will demonstrate Jigsaw Groups in action at a field stop. You'll see the crucial identification of critical concepts, small lab explorations carried out by the Expert Groups to master their assigned concepts, and Jigsaw Groups working a complex geological feature. You'll learn how to trouble-shoot less-than-successful first attempts and you'll leave with a step-by-step template that will allow you to adapt your existing activities to Jigsaw technique.

  4. Dynamical Critical Phenomena in Driven-Dissipative Systems

    NASA Astrophysics Data System (ADS)

    Sieberer, L. M.; Huber, S. D.; Altman, E.; Diehl, S.

    2013-05-01

    We explore the nature of the Bose condensation transition in driven open quantum systems, such as exciton-polariton condensates. Using a functional renormalization group approach formulated in the Keldysh framework, we characterize the dynamical critical behavior that governs decoherence and an effective thermalization of the low frequency dynamics. We identify a critical exponent special to the driven system, showing that it defines a new dynamical universality class. Hence critical points in driven systems lie beyond the standard classification of equilibrium dynamical phase transitions. We show how the new critical exponent can be probed in experiments with driven cold atomic systems and exciton-polariton condensates.

  5. Applying critical thinking to nursing.

    PubMed

    Price, Bob

    2015-08-19

    Critical thinking and writing are skills that are not easy to acquire. The term 'critical' is used differently in social and clinical contexts. Nursing students need time to master the inquisitive and ruminative aspects of critical thinking that are required in academic environments. This article outlines what is meant by critical thinking in academic settings, in relation to both theory and reflective practice. It explains how the focus of a question affects the sort of critical thinking required and offers two taxonomies of learning, to which students can refer when analysing essay requirements. The article concludes with examples of analytical writing in reference to theory and reflective practice.

  6. Group Work: How to Use Groups Effectively

    ERIC Educational Resources Information Center

    Burke, Alison

    2011-01-01

    Many students cringe and groan when told that they will need to work in a group. However, group work has been found to be good for students and good for teachers. Employers want college graduates to have developed teamwork skills. Additionally, students who participate in collaborative learning get better grades, are more satisfied with their…

  7. Are Earthquakes a Critical Phenomenon?

    NASA Astrophysics Data System (ADS)

    Ramos, O.

    2014-12-01

    Earthquakes, granular avalanches, superconducting vortices, solar flares, and even stock markets are known to evolve through power-law distributed events. During decades, the formalism of equilibrium phase transition has coined these phenomena as critical, which implies that they are also unpredictable. This work revises these ideas and uses earthquakes as the paradigm to demonstrate that slowly driven systems evolving through uncorrelated and power-law distributed avalanches (UPLA) are not necessarily critical systems, and therefore not necessarily unpredictable. By linking the correlation length to the pdf of the distribution, and comparing it with the one obtained at a critical point, a condition of criticality is introduced. Simulations in the classical Olami-Feder-Christensen (OFC) earthquake model confirm the findings, showing that earthquakes are not a critical phenomenon. However, one single catastrophic earthquake may show critical properties and, paradoxically, the emergence of this temporal critical behaviour may eventually carry precursory signs of catastrophic events.

  8. MSUD Family Support Group

    MedlinePlus

    ... Group The MSUD Family Support Group is a non-profit 501 (c)(3) organization for those with MSUD ... Family Support Group is a 501(c)(3) non-profit organization with no paid staff. Funds are needed ...

  9. Handheld computers in critical care

    PubMed Central

    Lapinsky, Stephen E; Weshler, Jason; Mehta, Sangeeta; Varkul, Mark; Hallett, Dave; Stewart, Thomas E

    2001-01-01

    Background Computing technology has the potential to improve health care management but is often underutilized. Handheld computers are versatile and relatively inexpensive, bringing the benefits of computers to the bedside. We evaluated the role of this technology for managing patient data and accessing medical reference information, in an academic intensive-care unit (ICU). Methods Palm III series handheld devices were given to the ICU team, each installed with medical reference information, schedules, and contact numbers. Users underwent a 1-hour training session introducing the hardware and software. Various patient data management applications were assessed during the study period. Qualitative assessment of the benefits, drawbacks, and suggestions was performed by an independent company, using focus groups. An objective comparison between a paper and electronic handheld textbook was achieved using clinical scenario tests. Results During the 6-month study period, the 20 physicians and 6 paramedical staff who used the handheld devices found them convenient and functional but suggested more comprehensive training and improved search facilities. Comparison of the handheld computer with the conventional paper text revealed equivalence. Access to computerized patient information improved communication, particularly with regard to long-stay patients, but changes to the software and the process were suggested. Conclusions The introduction of this technology was well received despite differences in users' familiarity with the devices. Handheld computers have potential in the ICU, but systems need to be developed specifically for the critical-care environment. PMID:11511337

  10. Instructional Effects on Critical Thinking: Performance on Ill-Defined Issues

    ERIC Educational Resources Information Center

    Angeli, Charoula; Valanides, Nicos

    2009-01-01

    Undergraduate students in dyads (N = 72) were randomly and equally assigned to four groups, namely three teaching groups (General, Infusion, and Immersion) and the control group. Students were initially administered the California Critical Thinking Skills Test (CCTST). After instruction, each dyad's critical-thinking performance on an ill-defined…

  11. Osteoarthritis: A Critical Review

    PubMed Central

    Onishi, Kentaro; Utturkar, Amol; Chang, Eric; Panush, Richard; Hata, Justin; Perret-Karimi, Danielle

    2015-01-01

    Patients with osteoarthritis (OA) are faced with a barrage of treatment options, from recommendations from friends and social media to medications prescribed by the primary care physician. The purpose of this article is to critically review current approaches to generalized or monoarticular OA based on available evidence and to illustrate multidisciplinary and multimodal treatment strategies for the management of OA. Treatment options assessed for efficacy include patient education; oral and topical pharmacological agents; complementary and alternative medicine; surgery; manual medicine; acupuncture; interventional procedures (corticosteroid injection, viscosupplementation, and pulsed radiofrequency); bracing; assistive devices; physical therapy; and physical modalities. Multidisciplinary and multimodal treatment strategies combined with early detection and prevention strategies provide the best benefit to patients. This review also illustrates that traditional and alternative modalities of treatment can be both synergistic and beneficial. Physicians should be aware of the variety of tools available for the management of OA and the associated symptoms. Those healthcare providers who can best individualize treatment plans for specific patients and inspire their patients to embrace healthy lifestyle modifications will achieve the best results. PMID:25750483

  12. Sepsis in critical care.

    PubMed

    King, Joan E

    2007-03-01

    Sepsis is a syndrome produced by the accelerated activity of the inflammatory immune response, the clotting cascade, and endothelial damage. It is a systematic process that can progress easily into septic shock and MODS. The chemical mediators or cytokines produce a complex self-perpetuating process that impacts all body systems. It is critical for the nurse first to identify patients at risk for developing sepsis and to assess patients who have SIRS and sepsis continually for signs and symptoms of organ involvement and organ dysfunction. Once sepsis has been diagnosed, evidence-based practice indicates initiation of fluid resuscitation. Vasopressor therapy, positive inotropic support, and appropriate antibiotic therapy should be started within the first hour. Within a 6-hour timeframe the goal is stabilization of the CVP, MAP, and UOP to prevent further organ damage. The challenge for nurses caring for septic patients is to support the treatment goals, to prevent added complications including stress ulcers, DVTs, aspiration pneumonia, and the progression to MODS, and to address the patient's and the family's psychosocial needs. As complex as the pathophysiology of sepsis is, the nursing care is equally complex but also rewarding. Patients who previously might have died now recover as vigilant nursing care combines forces with new drug therapies and evidence-based practice guidelines.

  13. Thermionic critical technology investigation

    NASA Astrophysics Data System (ADS)

    Jalichandra, P.; Hamerdinger, R. W.; Anderson, E. A.; Lamp, T. R.; Donovan, B. D.

    The thermionic critical technology investigation was initiated to enrich the technology base for thermionic space nuclear power systems. The focus of this program is on an out-of-core, Romashka type reactor system which can operate in the 5-40-kW range. The Romashka concept uses uranium carbide fuel in graphite trays which are radiatively coupled to planar thermionic converters. After completion of the design and fabrication of two state-of-the-art baseline converters, the baseline converters have been subject to further performance and life testing. To date, converter performance tests have been conducted for emitter temperatures from 1850 to 2000 K. The studies have shown that a thermionic converter with a heat-pipe-cooled collector is capable of high power conversion efficiency. By selecting the rhenium-rhenium system, in a closely spaced ignited mode converter, conversion efficiencies of 14 percent with a cell potential of 0.7 V can be readily attained. The sodium heat pipe provides a buffer against extreme changes in collector temperature due to fluctuations in converter load, one that can be improved upon by loading with an inert gas.

  14. Cohort: critical science

    NASA Astrophysics Data System (ADS)

    Digney, Bruce L.

    2007-04-01

    Unmanned vehicle systems is an attractive technology for the military, but whose promises have remained largely undelivered. There currently exist fielded remote controlled UGVs and high altitude UAV whose benefits are based on standoff in low complexity environments with sufficiently low control reaction time requirements to allow for teleoperation. While effective within there limited operational niche such systems do not meet with the vision of future military UxV scenarios. Such scenarios envision unmanned vehicles operating effectively in complex environments and situations with high levels of independence and effective coordination with other machines and humans pursing high level, changing and sometimes conflicting goals. While these aims are clearly ambitious they do provide necessary targets and inspiration with hopes of fielding near term useful semi-autonomous unmanned systems. Autonomy involves many fields of research including machine vision, artificial intelligence, control theory, machine learning and distributed systems all of which are intertwined and have goals of creating more versatile broadly applicable algorithms. Cohort is a major Applied Research Program (ARP) led by Defence R&D Canada (DRDC) Suffield and its aim is to develop coordinated teams of unmanned vehicles (UxVs) for urban environments. This paper will discuss the critical science being addressed by DRDC developing semi-autonomous systems.

  15. Criticality in the brain

    NASA Astrophysics Data System (ADS)

    de Arcangelis, L.; Lombardi, F.; Herrmann, H. J.

    2014-03-01

    Spontaneous brain activity has been recently characterized by avalanche dynamics with critical features for systems in vitro and in vivo. In this contribution we present a review of experimental results on neuronal avalanches in cortex slices, together with numerical results from a neuronal model implementing several physiological properties of living neurons. Numerical data reproduce experimental results for avalanche statistics. The temporal organization of avalanches can be characterized by the distribution of waiting times between successive avalanches. Experimental measurements exhibit a non-monotonic behaviour, not usually found in other natural processes. Numerical simulations provide evidence that this behaviour is a consequence of the alternation between states of high and low activity, leading to a balance between excitation and inhibition controlled by a single parameter. During these periods both the single neuron state and the network excitability level, keeping memory of past activity, are tuned by homoeostatic mechanisms. Interestingly, the same homoeostatic balance is detected for neuronal activity at the scale of the whole brain. We finally review the learning abilities of this neuronal network. Learning occurs via plastic adaptation of synaptic strengths by a non-uniform negative feedback mechanism. The system is able to learn all the tested rules and the learning dynamics exhibits universal features as a function of the strength of plastic adaptation. Any rule could be learned provided that the plastic adaptation is sufficiently slow.

  16. Critical dynamics in microgravity

    SciTech Connect

    Duncan, R.; Boyd, S.; Akau, R.; Gianoulakis, S.

    1996-05-01

    Although many well-controlled experiments have been conducted to measure the static properties of systems near criticality, few experiments have explored the transport properties in systems driven very far away from equilibrium as the transition occurs. Here we propose to measure the thermal gradient across the superfluid (HeII)-normal fluid (HeI) interface in microgravity conditions as a function of the heat flux Q used to make the measurements. Microgravity conditions are required (1) to avoid the hydrostatic pressure variation along the height of the helium column (a concern for Q<0.1 {mu}W {center_dot}cm {sup {minus}2}), (2) avoid convection in He-I for Q> 3 {mu}W {center_dot}cm{sup {minus}2} in our apparatus, and (3) to increase the Q=O interfacial width from its value of a few tens of microns on Earth to about a millimeter in orbit. New technologies described in this paper are under development for this experiment, which is in definition for Space Shuttle flight.

  17. Critical Systems Heuristics

    NASA Astrophysics Data System (ADS)

    Ulrich, Werner; Reynolds, Martin

    Critical systems heuristics (CSH) is a framework for reflective professional practice organised around the central tool of boundary critique. This paper, written jointly by the original developer, Werner Ulrich, and Martin Reynolds, an experienced practitioner of CSH, offers a systematic introduction to the idea and use of boundary critique. Its core concepts are explained in detail and their use is illustrated by means of two case studies from the domain of environmental planning and management. A particular focus is on working constructively with tensions between opposing perspectives as they arise in many situations of professional intervention. These include tensions such as ‘situation' versus ‘system', ‘is' versus ‘ought' judgements, concerns of ‘those involved' versus ‘those affected but not involved', stakeholders' ‘stakes' versus ‘stakeholding issues', and others. Accordingly, boundary critique is presented as a participatory process of unfolding and questioning boundary judgements rather than as an expert-driven process of boundary setting. The paper concludes with a discussion of some essential skills and considerations regarding the practice of boundary critique.

  18. Critical illness and changes in sensory perception.

    PubMed

    Schiffman, Susan S

    2007-08-01

    Impairments of sensory perception that occur during a period of critical care can seriously impact on health and nutritional status, activities of daily living, independence, quality of life and the possibility of recovery. It is emphasized from the outset that sensory losses in critically-ill patients may or may not be related to their current medical condition. The present paper provides an overview of all five senses (vision, hearing, taste, smell and touch) and describes the factors that contribute to sensory losses in critically-ill patients, including medications, medical conditions and treatments and the process of aging itself. Cancer and stroke are two critical illnesses in which profound sensory decrements often occur. Many sensory complaints in patients with cancer are related to alteration in sensory signals caused by damage to the sensory receptors. However, some complaints, such as taste aversions in patients with cancer, are not related to altered sensory physiology per se but to learned aversions that arise during the noxious effects of radiotherapy and chemotherapy. The paper also reviews a study in which the sensory performance (of all five senses) was compared in three groups of elderly subjects: (1) patients who had undergone coronary artery bypass surgery; (2) patients with cardiovascular conditions but with no history of surgery; (3) healthy non-medicated age-matched controls. Performance of patients who had undergone coronary artery bypass surgery was worse than that for the other two groups, with taste and smell losses greater than for the other senses. The study demonstrates that critical illness (e.g. coronary artery bypass surgery) can exacerbate sensory losses in an older cohort.

  19. T-Shaped Frame Critical and Post-Critical Analysis

    NASA Astrophysics Data System (ADS)

    Doicheva, Albena

    2016-03-01

    The paper shows solution of a T-shaped frame, strength- ened with two linear springs, regarding critical and post-critical analysis. The solution is exact using the Euler elastic approach and the frame of reference, originated in the point of column axis inflexion. The derived Numerical results show the effect of the springs strengthening for the crit- ical and the post-critical system behaviour. The influence of the geometry change is analyzed, as well.

  20. Healthcare Disparities in Critical Illness

    PubMed Central

    Soto, Graciela J.; Martin, Greg S.; Gong, Michelle Ng

    2013-01-01

    Objective To summarize the current literature on racial and gender disparities in critical care and the mechanisms underlying these disparities in the course of acute critical illness. Data Sources MEDLINE search on the published literature addressing racial, ethnic, or gender disparities in acute critical illness such as sepsis, acute lung injury, pneumonia, venous thromboembolism, and cardiac arrest. Study Selection Clinical studies that evaluated general critically ill patient populations in the United States as well as specific critical care conditions were reviewed with a focus on studies evaluating factors and contributors to health disparities. Data Extraction Study findings are presented according to their association with the incidence, clinical presentation, management, and outcomes in acute critical illness. Data Synthesis This review presents potential contributors for racial and gender disparities related to genetic susceptibility, comorbidities, preventive health services, socioeconomic factors, cultural differences, and access to care. The data is organized along the course of acute critical illness. Conclusions The literature to date shows that disparities in critical care are most likely multifactorial involving individual, community, and hospital-level factors at several points in the continuum of acute critical illness. The data presented identify potential targets as interventions to reduce disparities in critical care and future avenues for research. PMID:24121467

  1. Calculation of the absorbed dose for the overexposed patients at the JCO criticality accident in Tokai-mura.

    PubMed

    Ishigure, N; Endo, A; Yamaguchi, Y; Kawachi, K

    2001-09-01

    The doses for the overexposed patients were estimated by the measurement result of specific activity of 24Na in blood. The present method is almost based on documents of the International Atomic Energy Agency (IAEA) and the Oak Ridge National Laboratory. The neutron energy spectrum obtained using the ANISN code (Multigroup One-Dimensional Discrete Ordinates Transport Code System with Anisotropic Scattering) was assumed. The values in ICRP Publication 74 were applied for the doses in each organ per unit neutron fluence. Gamma-ray dose was indirectly estimated based on (a) the result of environmental monitoring around the accident site and (b) a graph in IAEA manual, which gives the kerma ratio of neutrons and gamma-rays as a function of the critical volume or the atomic ratio of hydrogen to 235U. The estimated neutron doses were 5.4 Gy for patient A. 2.9 Gy for patient B and 0.81 Gy for patient C. The estimated gamma-ray doses were 8.5 or 13 Gy for patient A, 4.5 or 6.9 Gy for patient B, and 1.3 or 2.0 Gy for patient C. PMID:11791747

  2. Effects of Metacognitive Guidance on Critical Thinking Disposition

    ERIC Educational Resources Information Center

    Akyüz, Halil Ibrahim; Samsa Yetik, Serap; Keser, Hafize

    2015-01-01

    The present study investigated the effect of metacognitive guidance in an online learning environment on the students' critical thinking competency. The research was carried out using experimental design with pretest-posttest control groups. The research group of the study consisted of 60 students studying at Computer and Educational Teaching…

  3. Peer led team learning in introductory biology: effects on peer leader critical thinking skills.

    PubMed

    Snyder, Julia J; Wiles, Jason R

    2015-01-01

    This study evaluated hypothesized effects of the Peer-Led Team Learning (PLTL) instructional model on undergraduate peer leaders' critical thinking skills. This investigation also explored peer leaders' perceptions of their critical thinking skills. A quasi-experimental pre-test/post-test with control group design was used to determine critical thinking gains in PLTL/non-PLTL groups. Critical thinking was assessed using the California Critical Thinking Skills Test (CCTST) among participants who had previously completed and been successful in a mixed-majors introductory biology course at a large, private research university in the American Northeast. Qualitative data from open-ended questionnaires confirmed that factors thought to improve critical thinking skills such as interaction with peers, problem solving, and discussion were perceived by participants to have an impact on critical thinking gains. However, no significant quantitative differences in peer leaders' critical thinking skills were found between pre- and post-experience CCTST measurements or between experimental and control groups.

  4. The Liver in Critical Illness.

    PubMed

    Damm, Tessa W; Kramer, David J

    2016-07-01

    Caring for critically ill patients with acute and/or chronic liver dysfunction poses a unique challenge. Proper resuscitation and early consideration for transfer to liver transplant centers have resulted in improved outcomes. Liver support devices and cellular models have not yet shown mortality benefit, but they hold promise in the critical care of patients with liver disease. This article reviews pertinent anatomic and physiologic considerations of the liver in critical illness, followed by a selective review of associated organ dysfunction. PMID:27339681

  5. Critical Viscosity of Xenon investigators

    NASA Technical Reports Server (NTRS)

    2001-01-01

    Dr. Dr. Robert F. Berg (right), principal investigator and Dr. Micheal R. Moldover (left), co-investigator, for the Critical Viscosity of Xenon (CVX/CVX-2) experiment. They are with the National Institutes of Standards and Technology, Gaithersburg, MD. 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. Although it does not easily combine with other chemicals, its viscosity at the critical point can be used as a model for a range of chemicals.

  6. Sharpening your critical thinking skills.

    PubMed

    Kyzer, S P

    1996-01-01

    In the current environment of constant and rapid change in health care, critical thinking is essential. Both personal ability to think critically and a willingness to do so are involved and are related to the individual and to the organization in which the individual works. Knowledge, experience, attitudes, thinking strategies, skills, and an organizational culture that values critical thinking are essential factors in the development and practice of those skills. There is no magic solution. There must be a commitment by all levels of the organization to develop and use the principles and skills of critical thinking. PMID:9110811

  7. Sharpening your critical thinking skills.

    PubMed

    Kyzer, S P

    1996-01-01

    In the current environment of constant and rapid change in health care, critical thinking is essential. Both personal ability to think critically and a willingness to do so are involved and are related to the individual and to the organization in which the individual works. Knowledge, experience, attitudes, thinking strategies, skills, and an organizational culture that values critical thinking are essential factors in the development and practice of those skills. There is no magic solution. There must be a commitment by all levels of the organization to develop and use the principles and skills of critical thinking.

  8. Effects of concept map teaching on students' critical thinking and approach to learning and studying.

    PubMed

    Chen, Shiah-Lian; Liang, Tienli; Lee, Mei-Li; Liao, I-Chen

    2011-08-01

    The purpose of this study was to explore the effects of concept mapping in developing critical thinking ability and approach to learning and studying. A quasi-experimental study design with a purposive sample was drawn from a group of nursing students enrolled in a medical-surgical nursing course in central Taiwan. Students in the experimental group were taught to use concept mapping in their learning. Students in the control group were taught by means of traditional lectures. After the intervention, the experimental group had better overall critical thinking scores than did the control group, although the difference was not statistically significant. After controlling for the effects of age and the pretest score on critical thinking using analysis of covariance, the experimental group had significantly higher adjusted mean scores on inference and overall critical thinking compared with the control group. Concept mapping is an effective tool for improving students' ability to think critically.

  9. Discipline-Based Art Education: Its Criticisms and Its Critics.

    ERIC Educational Resources Information Center

    Eisner, Elliot W.

    1988-01-01

    Discusses the criticisms of discipline-based art education published in the March 1988 issue of "Art Education." Responds to the arguments of Peter London, Helen Muth, Norma K. Pittard, and Karen Hamblen. States that art education would be better served if the energy devoted to criticism was directed toward constructive ends. (GEA)

  10. A Critical "Critical Inquiry" Proposition in Health and Physical Education

    ERIC Educational Resources Information Center

    Leahy, Deana; O'Flynn, Gabrielle; Wright, Jan

    2013-01-01

    A critical inquiry approach is one of five key characteristics that have shaped the development of the new Australian Curriculum: Health and Physical Education (AC: HPE). However, what this means is open to interpretation. In the various documents leading to the consultation draft AC: HPE and in this document itself, critical inquiry is used in…

  11. Do Critical Thinking Exercises Improve Critical Thinking Skills?

    ERIC Educational Resources Information Center

    Cotter, Ellen M.; Tally, Carrie Sacco

    2009-01-01

    Although textbooks routinely include exercises to improve critical thinking skills, the effectiveness of these exercises has not been closely examined. Additionally, the connection between critical thinking skills and formal operational thought is also relatively understudied. In the study reported here, college students completed measures of…

  12. How Critical Is Critical Thinking? FACTC Focus, 2010

    ERIC Educational Resources Information Center

    Doerr, Mark, Ed.

    2010-01-01

    "FACTC Focus" is a publication of Faculty Association of Community and Technical Colleges (FACTC) with the purpose of presenting diverse views on faculty issues. Included in this issue are: (1) LOL: The Easy ROUTE TO Critical Thinking (Barbara B. Parsons); (2) Critical Thinking: We Know It When We (Don't) See It (Jared Anthony); (3) Critical…

  13. Group Treatment in Acquired Brain Injury Rehabilitation

    ERIC Educational Resources Information Center

    Bertisch, Hilary; Rath, Joseph F.; Langenbahn, Donna M.; Sherr, Rose Lynn; Diller, Leonard

    2011-01-01

    The current article describes critical issues in adapting traditional group-treatment methods for working with individuals with reduced cognitive capacity secondary to acquired brain injury. Using the classification system based on functional ability developed at the NYU Rusk Institute of Rehabilitation Medicine (RIRM), we delineate the cognitive…

  14. Critical market crashes

    NASA Astrophysics Data System (ADS)

    Sornette, D.

    2003-04-01

    patterns have been documented for essentially all crashes on developed as well as emergent stock markets, on currency markets, on company stocks, and so on. We review this discovery at length and demonstrate how to use this insight and the detailed predictions obtained from these models to forecast crashes. For this, we review the major crashes of the past that occurred on the major stock markets of the planet and describe the empirical evidence of the universal nature of the critical log-periodic precursory signature of crashes. The concept of an “anti-bubble” is also summarized, with the Japanese collapse from the beginning of 1991 to present, taken as a prominent example. A prediction issued and advertised in January 1999 has been until recently born out with remarkable precision, predicting correctly several changes of trends, a feat notoriously difficult using standard techniques of economic forecasting. We also summarize a very recent analysis the behavior of the U.S. S&P500 index from 1996 to August 2002 and the forecast for the two following years. We conclude by presenting our view of the organization of financial markets.

  15. [Invasive candidiasis in critically ill adult patient].

    PubMed

    Tobar A, Eduardo; Silva O, Francisco; Olivares C, Roberto; Gaete G, Pablo; Luppi N, Mario

    2011-02-01

    Invasive infections by Candida strains are a relevant pathology in critically ill patients. Candida should be considered where a high risk of infection is present for a critical early diagnosis. Despite the incorporation of new drugs in the therapeutic armamentarium over the last decade, mortality remains high. The key in improving clinical outcomes of these patients are the use of early effective therapies that offer coverage against different strains of Candida: C. albicans and non-albicans. Recent international guidelines suggest empiric therapy with echinocandins in suspected invasive candidiasis in this patient population. This group of drugs adequately documented clinical efficacy and safe use in these patients. The emergence of new echinocandins could improve access to these drugs by reducing their cost.

  16. Developing postgraduate awards for critical care.

    PubMed

    Saggs, Pauline

    2003-05-01

    This report outlines a qualitative study that explored the academics' perceptions of postgraduate education for critical care. A framework was generated using models of curriculum design. Focus groups and interviews were undertaken to explore four areas within this framework - taught theory/professional practice, advanced practice skills, assessment and delivery. The findings revealed that ethical and legal aspects of role, research, physiology decision-making and practice skills such as defibrillation, first line treatment and patient assessment were considered extremely relevant to such a programme. Practice assessment was considered essential to ensure clinical credibility of the programme and the practitioner. Frameworks were generated to define the nature of advanced critical care practice. As such, work-based learning and interprofessional supervision were seen as key elements of the programme. Finally areas for further research were identified.

  17. Scrutiny of Critical Thinking Concept

    ERIC Educational Resources Information Center

    Atabaki, Ali Mohammad Siahi; Keshtiaray, Narges; Yarmohammadian, Mohammad H.

    2015-01-01

    Learning critical thinking skills are the goal of educational systems so the term "critical thinking" (CT) is frequently found in educational policy documents. Despite this frequency, however, precise understandings among teachers of what CT really means do not exit. The present study is designed to answer the following question. We can…

  18. Understanding Friendship between Critical Friends

    ERIC Educational Resources Information Center

    Gibbs, Paul; Angelides, Panayiotis

    2008-01-01

    This conceptual article discusses the issue of friendship implied by the term "critical friends". Our argument relates to the generalized use of the term "friendship" and the assumptions that it may carry compared with the actuality of the roles played by critical friends. We attempt to build a more precise definition of friendship which we…

  19. Willa Cather as Drama Critic.

    ERIC Educational Resources Information Center

    Jensen, Marvin D.

    Although Willa Cather is known primarily for her short fiction and novels, she began her writing career as a literary and drama critic while still a student at the University of Nebraska. Her writing experience with the university literary periodical led her to become the drama critic for the "Nebraska State Journal," and later for the "Lincoln…

  20. Critical Thinking in Physical Education

    ERIC Educational Resources Information Center

    Humphries, Charlotte

    2014-01-01

    Changes in American education require that teachers are evaluated more often, and expectations increasingly include teaching to develop critical thinking skills. This article uses Bloom's taxonomy in describing ways physical educators can include critical thinking in their lessons, both to enhance their teaching and to meet expectations of…

  1. Critical Issues Facing School Principals

    ERIC Educational Resources Information Center

    Styron, Ronald A., Jr.; Styron, Jennifer L.

    2011-01-01

    The purpose of this study was to further extend research initially conducted in 2003 pertaining to the critical issues K-12 principals address on a daily basis. The study involved surveying school principals within the state of Mississippi to discover the critical issues they identified, the significance level of these issues, and the rationale…

  2. Critical thinking in physics education

    NASA Astrophysics Data System (ADS)

    Sadidi, Farahnaz

    2016-07-01

    We agree that training the next generation of leaders of the society, who have the ability to think critically and form a better judgment is an important goal. It is a long-standing concern of Educators and a long-term desire of teachers to establish a method in order to teach to think critically. To this end, many questions arise on three central aspects: the definition, the evaluation and the design of the course: What is Critical Thinking? How can we define Critical Thinking? How can we evaluate Critical Thinking? Therefore, we want to implement Critical Thinking in physics education. How can we teach for Critical Thinking in physics? What should the course syllabus and materials be? We present examples from classical physics and give perspectives for astro-particle physics. The main aim of this paper is to answer the questions and provide teachers with the opportunity to change their classroom to an active one, in which students are encouraged to ask questions and learn to reach a good judgment. Key words: Critical Thinking, evaluation, judgment, design of the course.

  3. Continuous-time adaptive critics.

    PubMed

    Hanselmann, Thomas; Noakes, Lyle; Zaknich, Anthony

    2007-05-01

    A continuous-time formulation of an adaptive critic design (ACD) is investigated. Connections to the discrete case are made, where backpropagation through time (BPTT) and real-time recurrent learning (RTRL) are prevalent. Practical benefits are that this framework fits in well with plant descriptions given by differential equations and that any standard integration routine with adaptive step-size does an adaptive sampling for free. A second-order actor adaptation using Newton's method is established for fast actor convergence for a general plant and critic. Also, a fast critic update for concurrent actor-critic training is introduced to immediately apply necessary adjustments of critic parameters induced by actor updates to keep the Bellman optimality correct to first-order approximation after actor changes. Thus, critic and actor updates may be performed at the same time until some substantial error build up in the Bellman optimality or temporal difference equation, when a traditional critic training needs to be performed and then another interval of concurrent actor-critic training may resume. PMID:17526332

  4. A Place for Critical Literacy

    ERIC Educational Resources Information Center

    Beck, Ann S.

    2005-01-01

    The critical literacy classroom is characterized by an emphasis on students' voices and on dialogue as a tool with which students reflect on and construct meanings from texts and discourses. Is it appropriate, however, to teach critical literacy in settings such as penal institutions where student voices are deliberately discouraged and silenced?…

  5. Traditional Literacy and Critical Thinking

    ERIC Educational Resources Information Center

    Dando, Priscille

    2016-01-01

    How school librarians focus on activating critical thinking through traditional literacy development can proactively set the stage for the deep thinking that occurs in all literacy development. The critical-thinking skills students build while becoming accomplished readers and writers provide the foundation for learning in a variety of…

  6. Harnessing Critical Incidents for Learning

    ERIC Educational Resources Information Center

    Patahuddin, Sitti Maesuri; Lowrie, Tom

    2015-01-01

    A critical incident is a situation or event that holds significance for learning, both for the students and teachers. This paper presents four examples of critical incidents from a Year 7 teacher's lesson excerpts in Indonesia involving teaching of fractions, to show how they shaped classroom situation, brought forward elements of conflict, and…

  7. Quantifying Learning in Critical Thinking

    ERIC Educational Resources Information Center

    Fliegel, Richard; Holland, John

    2013-01-01

    This article describes a three-year study assessing change in critical thinking demonstrated in essays written for regular class assignments. A rubric was designed and scorers trained to assess critical thinking holistically without knowledge of the writing prompt or author's status. The longitudinal improvement in scores earned by freshmen…

  8. Cabbage Worms and Critical Thinking.

    ERIC Educational Resources Information Center

    Braswell, Patricia

    1993-01-01

    Argues that an approach to composition instruction that emphasizes critical thinking skills produces a more analytical writer. Describes a school project that examined research on critical thinking, implemented changes in the teaching of thinking and composition, and assessed student learning. (HB)

  9. Critical Pedagogy in Health Education

    ERIC Educational Resources Information Center

    Matthews, Catherine

    2014-01-01

    Objective: This review investigated how the three-phase model of critical pedagogy, based on the writings of Paulo Freire, can be put into practice in health education. Design: The study considers literature related to the fields of health education, health promotion and critical pedagogy. Setting: The study is a scholarly review completed as part…

  10. Teaching Students to Think Critically

    ERIC Educational Resources Information Center

    Black, Susan

    2005-01-01

    In this article, the author stresses that teachers need to teach their students to think critically and to reason their way. One prerequisite for teaching critical thinking is a classroom climate of high expectations, teacher warmth and encouragement, and pleasant physical surroundings. Schools should see to it that students become progressively…

  11. Education Studies: Issues & Critical Perspectives

    ERIC Educational Resources Information Center

    Kassem, Derek; Mufti, Emmanuel; Robinson, John

    2006-01-01

    This major text for Education Studies students provides a critical account of key issues in education today. The text features: (1) A critical analysis of key issues in Education Studies to encourage students' thinking about education in the broadest terms; (2) Themed sections with introductions to link the issues discussed in each chapter; (3)…

  12. Critical Thinking: Schemata vs. Skills.

    ERIC Educational Resources Information Center

    Brandhorst, Allan R.

    1989-01-01

    Refutes the idea that critical thinking is not a skill by analyzing it from the phenomenological perspective of Edmund Husserl, and from the hermeneutic perspective of Martin Heidegger. Develops the thesis that critical thinking is a restructuring of schemata. Addresses the problem of attention or student engagement. (LS)

  13. The GROOP Effect: Groups Mimic Group Actions

    ERIC Educational Resources Information Center

    Tsai, Jessica Chia-Chin; Sebanz, Natalie; Knoblich, Gunther

    2011-01-01

    Research on perception-action links has focused on an interpersonal level, demonstrating effects of observing individual actions on performance. The present study investigated perception-action matching at an inter-group level. Pairs of participants responded to hand movements that were performed by two individuals who used one hand each or they…

  14. Some Observations on Specifying Models of Group Performance.

    ERIC Educational Resources Information Center

    Goodman, Paul; And Others

    The purpose of this paper is to identify some critical dimensions in specifying a model of group performance. In the first section, the boundaries of the paper, e.g., work groups that produce some identifiable good or service, are discussed. In the second section some models of group performance are explored in order to illustrate theories of…

  15. The Influence of Cognitive Diversity on Group Problem Solving Strategy

    ERIC Educational Resources Information Center

    Lamm, Alexa J.; Shoulders, Catherine; Roberts, T. Grady; Irani, Tracy A.; Snyder, Lori J. Unruh; Brendemuhl, Joel

    2012-01-01

    Collaborative group problem solving allows students to wrestle with different interpretations and solutions brought forth by group members, enhancing both critical thinking and problem solving skills. Since problem solving in groups is a common practice in agricultural education, instructors are often put in the position of organizing student…

  16. Finding Fault: Causality and Counterfactuals in Group Attributions

    ERIC Educational Resources Information Center

    Zultan, Ro'i; Gerstenberg, Tobias; Lagnado, David A.

    2012-01-01

    Attributions of responsibility play a critical role in many group interactions. This paper explores the role of causal and counterfactual reasoning in blame attributions in groups. We develop a general framework that builds on the notion of pivotality: an agent is pivotal if she could have changed the group outcome by acting differently. In three…

  17. ANS-8. 23: Criticality accident emergency planning and response

    SciTech Connect

    Pruvost, N.L.

    1991-06-24

    A study group has been formed under the auspices of ANS-8 to examine the need for a standard on nuclear criticality accident emergency planning and response. This standard would be ANS-8.23. ANSI/ANS-8.19-1984, Administrative Practices for Nuclear Criticality Safety, provides some guidance on the subject in Section 10 titled -- Planned Response to Nuclear Criticality Accidents. However, the study group has formed a consensus that Section 10 is inadequate in that technical guidance in addition to administrative guidance is needed. The group believes that a new standard which specifically addresses emergency planning and response to a perceived criticality accident is needed. Plans for underway to request the study group be designated a writing group to create a draft of such a new standard. The proposed standard will divide responsibility between management and technical staff. Generally, management will be charged with providing the necessary elements of emergency planning such as a criticality detection and alarm system, training, safe evacuation routes and assembly areas, a system for timely accountability of personnel, and an effective emergency response organization. The technical staff, on the other hand, will be made responsible for establishing specific items such as safe and clearly posted evacuation evacuation routes and dose criteria for personnel assembly areas. The key to the question of responsibilities is that management must provide the resources for the technical staff to establish the elements of an emergency response effort.

  18. Gestalt Interactional Groups

    ERIC Educational Resources Information Center

    Harman, Robert L.; Franklin, Richard W.

    1975-01-01

    Gestalt therapy in groups is not limited to individual work in the presence of an audience. Describes several ways to involve gestalt groups interactionally. Interactions described focus on learning by doing and discovering, and are noninterpretive. (Author/EJT)

  19. What Makes Groups Tick.

    ERIC Educational Resources Information Center

    Allcorn, Seth

    1985-01-01

    By reviewing this analysis of the behavior of both groups and individuals in groups, human resources managers can learn to tell whether committees, task forces, and departments may be encouraging or inhibiting the work they set out to do. (Author)

  20. Nilpotent -local finite groups

    NASA Astrophysics Data System (ADS)

    Cantarero, José; Scherer, Jérôme; Viruel, Antonio

    2014-10-01

    We provide characterizations of -nilpotency for fusion systems and -local finite groups that are inspired by known result for finite groups. In particular, we generalize criteria by Atiyah, Brunetti, Frobenius, Quillen, Stammbach and Tate.