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Explicit
Terms modified by Explicit Selected AbstractsExplicit coupled thermo-mechanical finite element model of steel solidificationINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 1 2009Seid Koric Abstract The explicit finite element method is applied in this work to simulate the coupled and highly non-linear thermo-mechanical phenomena that occur during steel solidification in continuous casting processes. Variable mass scaling is used to efficiently model these processes in their natural time scale using a Lagrangian formulation. An efficient and robust local,global viscoplastic integration scheme (Int. J. Numer. Meth. Engng 2006; 66:1955,1989) to solve the highly temperature- and rate-dependent elastic,viscoplastic constitutive equations of solidifying steel has been implemented into the commercial software ABAQUS/Explicit (ABAQUS User Manuals v6.7. Simulia Inc., 2007) using a VUMAT subroutine. The model is first verified with a known semi-analytical solution from Weiner and Boley (J. Mech. Phys. Solids 1963; 11:145,154). It is then applied to simulate temperature and stress development in solidifying shell sections in continuous casting molds using realistic temperature-dependent properties and including the effects of ferrostatic pressure, narrow face taper, and mechanical contact. Example simulations include a fully coupled thermo-mechanical analysis of a billet-casting and thin-slab casting in a funnel mold. Explicit temperature and stress results are compared with the results of an implicit formulation and computing times are benchmarked for different problem sizes and different numbers of processor cores. The explicit formulation exhibits significant advantages for this class of contact-solidification problems, especially with large domains on the latest parallel computing platforms. Copyright © 2008 John Wiley & Sons, Ltd. [source] A design database for moulded pulp packaging structurePACKAGING TECHNOLOGY AND SCIENCE, Issue 4 2004X. Ma Abstract In this study, a structural factor approach is developed to allow a modular design method be used for the packaging design of thin-walled structures. Numerical simulations of the structural units are carried out to evaluate the influence of the structural factors under static loading, by using the commercial finite element code ABAQUS/Explicit. Empirical relations between the load-bearing capacity of structural units and structural factors are established based on numerical simulations. A database is then constructed that has the ability to provide valuable information for the loading performances of different structural units. Copyright © 2004 John Wiley & Sons, Ltd. [source] Numerical analysis of a new Eulerian,Lagrangian finite element method applied to steady-state hot rolling processesINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 5 2005Josef Synka Abstract A finite element code for steady-state hot rolling processes of rigid,visco-plastic materials under plane,strain conditions was developed in a mixed Eulerian,Lagrangian framework. This special set up allows for a direct calculation of the local deformations occurring at the free surfaces outside the contact region between the strip and the work roll. It further simplifies the implementation of displacement boundary conditions, such as the impenetrability condition. When applied to different practical hot rolling situations, ranging from thick slab to ultra-thin strip rolling, the velocity,displacement based model (briefly denoted as vu-model) in this mixed Eulerian,Lagrangian reference system proves to be a robust and efficient method. The vu-model is validated against a solely velocity-based model (vv-model) and against elementary methods based on the Kármán,Siebel and Orowan differential equations. The latter methods, when calibrated, are known to be in line with experimental results for homogeneous deformation cases. For a massive deformation it is further validated against the commercial finite-element software package Abaqus/Explicit. It is shown that the results obtained with the vu-model are in excellent agreement with the predictions of the vv-model and that the vu-model is even more robust than its vv-counterpart. Throughout the study we assumed a rigid cylindrical work roll; only for the homogeneous test case, we also investigated the effect of an elastically deformable work roll within the frame of the Jortner Green's function method. The new modelling approach combines the advantages of conventional Eulerian and Lagrangian modelling concepts and can be extended to three dimensions in a straightforward manner. Copyright © 2004 John Wiley & Sons, Ltd. [source] Mediation, power, and cultural differenceCONFLICT RESOLUTION QUARTERLY, Issue 3 2003Morgan Brigg In Western mediation practice, conflict and violence are typically seen as destructive and unhelpful ways of being, and this does not allow for the constitutive and productive role of conflict in many non-Western traditions. The playing out of these assumptions in mediation practice effects an operation of power that is particularly significant in intercultural mediations. Explicit and implicit mediator techniques lead disputants in intercultural mediations to behave in ways consistent with the goals of mediation and Western norms around conflict and selfhood. The specificity of this analysis means that the findings are indicative and explorative rather than comprehensive. Nevertheless, the results highlight the need to consider ways in which researchers and mediators can begin to mitigate this operation of power and respond to cultural difference in ethical ways. [source] A phenomenological study of spirituality and learning processes at work: Exploring the holistic theory of knowledge and learningHUMAN RESOURCE DEVELOPMENT QUARTERLY, Issue 4 2007Suzanne J. Gallagher The holistic theory of knowledge and learning offers an integrative framework for understanding the interactions of cognitions, feelings, and behavior in learning. Explicit (cognitions), implicit ( behavior), and emancipatory (feelings, values, spirituality) knowledge facets interact in learning processes. Little is known, however, about the nature of these interactions and the role of spirituality in learning. A phenomenological study of professionals' learning processes at work showed that knowledge facets interact in learning through expressing, informing, changing, and guiding one another. Complex interactions within knowledge facets were identified as well as the dangers of learning using only one knowledge facet. The essential role of community in learning processes was affirmed, and the guiding, informing role of spirituality in learning at work was revealed. [source] A systematic review and meta-synthesis: evaluating the effectiveness of nurse, midwife/allied health professional consultantsJOURNAL OF CLINICAL NURSING, Issue 10 2007Ann Humphreys PhD, Cert Ed Aim., This paper presents the findings of a systematic review and meta-synthesis, which was undertaken to identify and assess studies that evaluated the nurse/midwife/allied health professional consultant role. Background., As part of the modernization agenda in the National Health Service the United Kingdom government proposed ,Consultant' posts for nurses/midwives and allied health professionals as an opportunity for experienced practitioners to extend their roles. Four key functions were identified as being significant to this role development: expert practice, leadership, education and research. Explicit within the proposal was a requirement of these new roles to be evaluated. Method., Inclusion criteria focussed on studies where an aspect of the role had been evaluated or where the consultant carried out the research. A total of 1931 citations was filtered to reveal 107 studies that possibly met the inclusion criteria. Of these 107, 14 studies were critically appraised and subjected to thematic analysis. Study methodology varied but of the 14 studies, 10 involved some form of measurement. The others adopted a literature review or descriptive approach. Conclusions., The extent to which consultants were involved in all aspects of the ,four pillars' was assessed in only a small number of studies. However, a number of studies implicitly implied active engagement in expert practice and leadership by focussing on specific service developments. Relevance to clinical practice., To date, a number of studies evaluating service developments, education, expert practice and leadership have been carried out. However although a number of studies have assessed perceived impact of the consultant role, no measure of actual benefit has been published to date. Studies that evaluate the cost benefit/outcomes of these roles in relation to both activity and quality of service are required. [source] Second Language Acquisition of Gender Agreement in Explicit and Implicit Training Conditions: An Event-Related Potential StudyLANGUAGE LEARNING, Issue 1 2010Kara Morgan-Short This study employed an artificial language learning paradigm together with a combined behavioral/event-related potential (ERP) approach to examine the neurocognition of the processing of gender agreement, an aspect of inflectional morphology that is problematic in adult second language (L2) learning. Subjects learned to speak and comprehend an artificial language under either explicit (classroomlike) or implicit (immersionlike) training conditions. In each group, both noun-article and noun-adjective gender agreement processing were examined behaviorally and with ERPs at both low and higher levels of proficiency. Results showed that the two groups learned the language to similar levels of proficiency but showed somewhat different ERP patterns. At low proficiency, both types of agreement violations (adjective, article) yielded N400s, but only for the group with implicit training. Additionally, noun-adjective agreement elicited a late N400 in the explicit group at low proficiency. At higher levels of proficiency, noun-adjective agreement violations elicited N400s for both the explicit and implicit groups, whereas noun-article agreement violations elicited P600s for both groups. The results suggest that interactions among linguistic structure, proficiency level, and type of training need to be considered when examining the development of aspects of inflectional morphology in L2 acquisition. [source] Absence of explicit and implicit memory in unconscious patients using a TCI of propofolACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 7 2003P. Y. Lequeux Background:, ,Episodes of implicit memory have been described during propofol anaesthesia. It remains unclear whether implicit memory is caused by short periods of awareness or occurs in an unconscious subject. Methods:, Sixty patients were randomized in an experimental group (EG), a control group (CG) and a reference group (RG). Loss of consciousness (LOC) was obtained by progressive stepwise increases of propofol using a target-controlled infusion device (Diprifusor, Alaris Medical Systems, San Diego, CA). A tape containing 20 words was played to the patients in the CG before the start of anaesthesia and to the patients in the EG at a constant calculated concentration of propofol associated with LOC. The tape was not played to the patients in the RG. Three memory tests were performed postoperatively. Results:, Explicit and implicit memories were evidenced in the CG but not in the EG. Conclusion:, In our group of young ASA I/II patients, in the absence of any noxious stimulus, no implicit or explicit memory was found when the calculated concentration of propofol using a Diprifusor was maintained at the level associated with LOC. [source] Cognitive-behavioural rehabilitation of high-risk violent offenders: Investigating treatment change with explicit and implicit measures of cognitionAPPLIED COGNITIVE PSYCHOLOGY, Issue 3 2010Devon L. L. Polaschek Important as it is both to risk of re-offending and to cognitive behavioural treatment, violent cognition is seldom measured in rehabilitation programmes, and even more rarely linked to measures of violence risk. Most often, researchers measure violent cognition by having offenders complete transparent self-report questionnaires. This approach may be flawed both by socially desirable responding and by theoretical speculation that stronger links exist between automatic rather than explicit, consciously deliberated cognition and violent behaviour. We measured violent cognition in several ways; collecting data with two self-report scales, along with two Implicit Association Tests (IATs) from men commencing and completing an intensive cognitive-behavioural rehabilitation programme for high-risk violent prisoners. We addressed the questions of whether these two forms of assessment,explicit and implicit,are related, and which is most strongly linked to estimates of violence, based on the Violence Risk Scale. Explicit and implicit tests were not related to each other, although both self-report scales, and one of the IATs elicited significantly more pro-social responses following treatment. Further, the Aggression Questionnaire (AQ) scores were significantly correlated with dynamic risk both pre- and post-programme, while post-programme, scores on one of the two IATs was significantly correlated with dynamic and static risk, as measured pre- and post-programme. These findings suggest that implicit and explicit measures may be assessing different aspects of cognition, and only some are related to violence risk. Copyright © 2010 John Wiley & Sons, Ltd. [source] Two faces of human happiness: Explicit and implicit life satisfactionASIAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 3 2009Daisung Jang Evidence is provided for implicit aspects of life satisfaction. In study 1 the implicit life satisfaction measure (ILS): (i) showed moderate reliability as well as convergent and incremental validity; (ii) appeared to be affected by temporary mood and social desirability to a lesser extent than explicit measures; and (iii) showed cultural invariance in contrast to explicit measures that revealed cross-cultural differences, as found in previous research. Study 2 showed that the ILS replicated theoretically expected differences between those known to have encountered chronically negative life experiences (North Korean defectors) and those without such experiences (South Koreans). Implications of these findings for explicit and ILS are discussed. [source] Replica Exchange Light TransportCOMPUTER GRAPHICS FORUM, Issue 8 2009Shinya Kitaoka I.3.7 [Computer Graphics]: Three-Dimensional Graphics and Realism; I.3.3 [Computer Graphics]: Picture/Image Generation Abstract We solve the light transport problem by introducing a novel unbiased Monte Carlo algorithm called replica exchange light transport, inspired by the replica exchange Monte Carlo method in the fields of computational physics and statistical information processing. The replica exchange Monte Carlo method is a sampling technique whose operation resembles simulated annealing in optimization algorithms using a set of sampling distributions. We apply it to the solution of light transport integration by extending the probability density function of an integrand of the integration to a set of distributions. That set of distributions is composed of combinations of the path densities of different path generation types: uniform distributions in the integral domain, explicit and implicit paths in light (particle/photon) tracing, indirect paths in bidirectional path tracing, explicit and implicit paths in path tracing, and implicit caustics paths seen through specular surfaces including the delta function in path tracing. The replica-exchange light transport algorithm generates a sequence of path samples from each distribution and samples the simultaneous distribution of those distributions as a stationary distribution by using the Markov chain Monte Carlo method. Then the algorithm combines the obtained path samples from each distribution using multiple importance sampling. We compare the images generated with our algorithm to those generated with bidirectional path tracing and Metropolis light transport based on the primary sample space. Our proposing algorithm has better convergence property than bidirectional path tracing and the Metropolis light transport, and it is easy to implement by extending the Metropolis light transport. [source] Steady-State Analysis of Water Distribution Networks Including Pressure-Reducing ValvesCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 4 2001L. Khezzar Hydraulic networks that contain controlling elements such as pressure-reducing valves (PRVs) are difficult to simulate. Limited literature exists on the explicit modeling of PRVs in a general solution procedure for steady-state analysis of water distribution systems. It is also known that inclusion of PRVs may lead to numerical difficulties. The objective of this article is to develop and present in sufficient detail the modeling of PRVs in combination with the linear theory method for steady-state analysis of water distribution networks. The presentation is explicit enough and leads to a robust algorithm that can be directly implemented in a computer program. The general methodology for simulating water distribution networks that embodies graph theoretic concepts, hydraulic theory, and numerical algorithms is reviewed. [source] Checking ownership and confinementCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 7 2004Alex Potanin Abstract A number of proposals to manage aliasing in Java-like programming languages have been advanced over the last five years. It is not clear how practical these proposals are, that is, how well they relate to the kinds of programs currently written in Java-like languages. To address this problem, we analysed heap snapshots from a corpus of Java programs. Our results indicate that object-oriented programs do in fact exhibit symptoms of encapsulation in practice, and that proposed models of uniqueness, ownership, and confinement can usefully describe the aliasing structures of object-oriented programs. Understanding the kinds of aliasing present in programs should help us to design formalisms to make explicit the kinds of aliasing implicit in object-oriented programs. Copyright © 2004 John Wiley & Sons, Ltd. [source] Accounting Recognition, Moral Hazard, and Communication,CONTEMPORARY ACCOUNTING RESEARCH, Issue 3 2000PIERRE JINGHONG LIANG Abstract Two complementary sources of information are studied in a multiperiod agency model. One is an accounting source that partially but credibly conveys the agent's private information through accounting recognition. The other is an unverified communication by the agent (i.e., a self-report). In a simple setting with no communication, alternative labor market frictions lead to alternative optimal recognition policies. When the agent is allowed to communicate his or her private information, accounting signals serve as a veracity check on the agent's self-report. Finally, such communication sometimes makes delaying the recognition optimal. We see contracting and confirmatory roles of accounting as its comparative advantage. As a source of information, accounting is valuable because accounting reports are credible, comprehensive, and subject to careful and professional judgement. While other information sources may be more timely in providing valuation information about an entity, audited accounting information, when used in explicit or implicit contracts, ensures the accuracy of the reports from nonaccounting sources. [source] Curricular Theorizing From the PeripheryCURRICULUM INQUIRY, Issue 5 2008ANGELINA WEENIE ABSTRACT The purpose of this article is to propose theory and knowledge from the peripheral space. Through an analysis of historical and contemporary perspectives of curriculum, the intent of this article is to make explicit the story of curriculum, and the influence of poststructuralist, postmodern, and postcolonial paradigms on the development of Aboriginal curriculum. This article will explore the philosophical and ontological basis of Aboriginal knowledge and its implications for curricular theory. [source] Charity Basket or Revolution: Beliefs, Experiences, and Context in Preservice Teachers' Service LearningCURRICULUM INQUIRY, Issue 4 2000David M. Donahue Given what one observer calls the "vast disparity of definitions that faculty can bring to service learning,from what is basically the charity basket approach to the revolutionary," service learning can varytremendously, from reading to elderly residents of a nursing home to organizing a boycott of a sneaker company. With such diversity before teachers, what influences them in the way they design service learning? How do preservice teachers, for whom so many ideas about teaching are emerging, make such choices? Two case studies suggest that preservice teachers' beliefs, experiences, and the context where they teach play an important role related to if and how they use service learning. Beliefs and experiences are especially important because, although service learning is often presented as supporting apolitical values,empowerment and responsibility, for example,for which broad consensus exists, such values are also ambiguous and open to interpretation. Teacher educators and advocates of service learning need to acknowledge the ambiguous political nature of service and service learning. By doing so, they have an opportunity to make the political context of teaching explicit for preservice teachers. Such education in service learning for new teachers goes beyond "training" in the logistical and technical details of implementing a new pedagogy to thoughtful reflection on the value-laden act of teaching. [source] Functional Interpretations of Constructive Set Theory in All Finite TypesDIALECTICA, Issue 2 2008Justus Diller Gödel's dialectica interpretation of Heyting arithmetic HA may be seen as expressing a lack of confidence in our understanding of unbounded quantification. Instead of formally proving an implication with an existential consequent or with a universal antecedent, the dialectica interpretation asks, under suitable conditions, for explicit ,interpreting' instances that make the implication valid. For proofs in constructive set theory CZF - , it may not always be possible to find just one such instance, but it must suffice to explicitly name a set consisting of such interpreting instances. The aim of eliminating unbounded quantification in favor of appropriate constructive functionals will still be obtained, as our ,-interpretation theorem for constructive set theory in all finite types CZF, - shows. By changing to a hybrid interpretation ,q, we show closure of CZF, - under rules that , in stronger forms , have already been studied in the context of Heyting arithmetic. In a similar spirit, we briefly survey modified realizability of CZF, - and its hybrids. Central results of this paper have been proved by Burr 2000a and Schulte 2006, however, for different translations. We use a simplified interpretation that goes back to Diller and Nahm 1974. A novel element is a lemma on absorption of bounds which is essential for the smooth operation of our translation. [source] An Essay on the Role of Language in Collegiate Foreign Language Programmatic Reform,DIE UNTERRICHTSPRAXIS/TEACHING GERMAN, Issue 2 2009Hiram Maxim This position paper argues that collegiate foreign language (FL) education has lost sight of the central role that language plays in the profession. Regardless of one's sub-field within foreign language education (i.e., linguistic, literary, or cultural studies), the profession shares the common focus of exploring how to make and interpret meaning in and through language. The paper therefore recommends that an acknowledgement of and re-commitment to this foundational principle provides common ground to effect the types of change within departments that have long been called: the integration of upper- and lower-level instruction; the reform of graduate student teacher education to foster curricular thinking; the explicit and systematic attention to the development of advanced language abilities; and the establishment of a collaborative departmental culture centered around publicly shared beliefs and concerns. [source] Operator-splitting method for real-time substructure testingEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 3 2006Bin Wu Abstract It has been shown that the operator-splitting method (OSM) provides explicit and unconditionally stable solutions for quasi-static pseudo-dynamic substructure testing. However, the OSM provides only an explicit target displacement but not an explicit target velocity, so that it is essentially an implicit method for real-time substructure testing (RST) when the velocity-dependent restoring force is considered. This paper proposes a target velocity formulation based on the forward difference of the predicted displacements so as to render the OSM explicit for RST. The stability and accuracy of the resulting OSM-RST algorithm are investigated. It is shown that the OSM-RST is unconditionally stable so long as the non-linear stiffness and damping are of the softening type (i.e. the tangent stiffness and damping never exceed the initial values). The stability of the OSM-RST for structures with infinite tangent damping coefficient or stiffness is also proved, and the stability of the method for MDOF structures with a non-classical damping matrix is demonstrated by an energy criterion. The effects of actuator delay and compensation are analysed based on the bilinear approximation of the actuator step response. Experiments on damped SDOF and MDOF structures verify that the stability of the OSM-RST is preserved when the experimental substructure generates velocity-dependent reaction forces, whereas the stability of real-time substructure tests based on the central difference method is worsened by the damping of the specimen. Copyright © 2005 John Wiley & Sons, Ltd. [source] Coefficient shifts in geographical ecology: an empirical evaluation of spatial and non-spatial regressionECOGRAPHY, Issue 2 2009L. Mauricio Bini A major focus of geographical ecology and macroecology is to understand the causes of spatially structured ecological patterns. However, achieving this understanding can be complicated when using multiple regression, because the relative importance of explanatory variables, as measured by regression coefficients, can shift depending on whether spatially explicit or non-spatial modeling is used. However, the extent to which coefficients may shift and why shifts occur are unclear. Here, we analyze the relationship between environmental predictors and the geographical distribution of species richness, body size, range size and abundance in 97 multi-factorial data sets. Our goal was to compare standardized partial regression coefficients of non-spatial ordinary least squares regressions (i.e. models fitted using ordinary least squares without taking autocorrelation into account; "OLS models" hereafter) and eight spatial methods to evaluate the frequency of coefficient shifts and identify characteristics of data that might predict when shifts are likely. We generated three metrics of coefficient shifts and eight characteristics of the data sets as predictors of shifts. Typical of ecological data, spatial autocorrelation in the residuals of OLS models was found in most data sets. The spatial models varied in the extent to which they minimized residual spatial autocorrelation. Patterns of coefficient shifts also varied among methods and datasets, although the magnitudes of shifts tended to be small in all cases. We were unable to identify strong predictors of shifts, including the levels of autocorrelation in either explanatory variables or model residuals. Thus, changes in coefficients between spatial and non-spatial methods depend on the method used and are largely idiosyncratic, making it difficult to predict when or why shifts occur. We conclude that the ecological importance of regression coefficients cannot be evaluated with confidence irrespective of whether spatially explicit modelling is used or not. Researchers may have little choice but to be more explicit about the uncertainty of models and more cautious in their interpretation. [source] The spatial pattern of soil-dwelling termites in primary and logged forest in Sabah, MalaysiaECOLOGICAL ENTOMOLOGY, Issue 1 2007SARAH E. DONOVAN Abstract 1.,Primary and logged lowland dipterocarp forest sites were sampled for subterranean termites using soil pits located on a grid system in order to detect any patchiness in their distribution. 2.,A spatial pattern in termite distributions was observed in the primary and logged sites, but the response differed between soil-feeding and non-soil-feeding termites. 3.,Spatial analysis showed that soil-feeding termites were homogeneously distributed in the primary forest but significantly aggregated in the logged forest. This pattern was reversed for non-soil-feeding termites and may result from differences in resource provisioning between the two sites. 4.,Gaps in termite distribution comprised a greater area than patches for both feeding groups and sites, but gaps dominated the logged site. 5.,A significant association between soil-feeding and non-soil-feeding termite distributions occurred at both sites. This arose from an association between patches in the primary forest and between gaps in the logged forest. 6.,Termite spatial pattern was optimally observed at a minimum extent of 64 m and lag of 2 m. 7.,The spatially explicit SADIE (Spatial Analysis by Distances IndicEs) analyses were more successful than (non-spatially explicit) multivariate analysis (Canonical Correspondence Analysis) at detecting associations between termite spatial distributions and that of other biotic and abiotic variables. [source] Advancing the metabolic theory of biodiversityECOLOGY LETTERS, Issue 10 2009James C. Stegen Abstract A component of metabolic scaling theory has worked towards understanding the influence of metabolism over the generation and maintenance of biodiversity. Specific models within this ,metabolic theory of biodiversity' (MTB) have addressed temperature gradients in speciation rate and species richness, but the scope of MTB has been questioned because of empirical departures from model predictions. In this study, we first show that a generalized MTB is not inconsistent with empirical patterns and subsequently implement an eco-evolutionary MTB which has thus far only been discussed qualitatively. More specifically, we combine a functional trait (body mass) approach and an environmental gradient (temperature) with a dynamic eco-evolutionary model that builds on the current MTB. Our approach uniquely accounts for feedbacks between ecological interactions (size-dependent competition and predation) and evolutionary rates (speciation and extinction). We investigate a simple example in which temperature influences mutation rate, and show that this single effect leads to dynamic temperature gradients in macroevolutionary rates and community structure. Early in community evolution, temperature strongly influences speciation and both speciation and extinction strongly influence species richness. Through time, niche structure evolves, speciation and extinction rates fall, and species richness becomes increasingly independent of temperature. However, significant temperature-richness gradients may persist within emergent functional (trophic) groups, especially when niche breadths are wide. Thus, there is a strong signal of both history and ecological interactions on patterns of species richness across temperature gradients. More generally, the successful implementation of an eco-evolutionary MTB opens the perspective that a process-based MTB can continue to emerge through further development of metabolic models that are explicit in terms of functional traits and environmental gradients. [source] The challenge of external validity in policy-relevant systematic reviews: a case study from the field of substance misuseADDICTION, Issue 1 2010Mark Pearson ABSTRACT Aim To critically evaluate the methods utilized in the conduct of a systematic review in the field of substance misuse Design Participant-observation in the review process, semi-structured interviews with review team members and management and structured observation of the process of guidance development. Setting An ,arm's-length' government body. Participants Review team members, management and the committee responsible for producing evidence-based guidance for policy and practice. Measurements Data from interviews and (participant-)observation were reflected upon critically in order to increase understanding of the systematic review process. Findings The application of systematic review methods produced an evidence base that did not inform the development of guidance to the extent that it could have done: (i) an emphasis upon internal research validity produced an evidence base with an emphasis on short-term interventions at the level of the individual; (ii) criteria for appraising the external validity of studies were not developed sufficiently; and (iii) the systematic review of evidence and development of guidance are strongly reliant upon the judgement of reviewers and committee members. Conclusions Prioritizing internal validity in a systematic review risks producing an evidence base that is not informed adequately by the wider determinants of health and which does not give sufficient consideration to external validity. The use of appropriate methods requires that commissioners of systematic reviews are clear at the outset how the review is proposed to be utilized. Review methods such as meta-ethnography and realist synthesis could contribute to making the frameworks within which judgements are made more explicit. [source] Brownjohn, Hughes, Pirrie, and Rosen: What Rhymes with Oral Writing?ENGLISH IN EDUCATION, Issue 2 2001Anthony Wilson Abstract This article looks at the work of four writers who have had considerable influence on the teaching of poetry writing to primary school children. Each writer is considered in terms of their merits as a contributor to wider questions about writing, and in comparative terms with each other. Links are made between these writers' explicit and implicit philosophies and approaches. Finally, the article considers how far discussions about voice and form within children's writing are necessarily exclusive of each other. [source] Using framing parameters to improve handling of uncertainties in water management practiceENVIRONMENTAL POLICY AND GOVERNANCE, Issue 2 2010Nicola Isendahl Abstract Management of water resources is afflicted with uncertainties. Nowadays it is facing more and new uncertainties since the pace and dimension of changes (e.g. climatic, demographic) are accelerating and are likely to increase even more in the future. Hence it is crucial to find pragmatic ways to deal with these uncertainties in water management. We argue for an analytical yet pragmatic approach to enable decision-makers to deal with uncertainties in a more explicit and systematic way and allow for better informed decisions. Our approach is based on the concept of framing, referring to the different ways in which people make sense of the world and of the uncertainties. We apply recently developed parameters of the framing of uncertainty in two sub-basins of the Rhine, the Dutch Kromme Rijn and the German Wupper. We present and discuss the results of a series of stakeholder interactions in the two basins aimed at developing strategies for improving dealing with uncertainties. The strategies are amended and synthesized in a check-list based on the uncertainty framing parameters as a hands-on tool for systematically identifying improvement options when dealing with uncertainty in water management practice. We conclude with suggestions for testing the developed check-list as a tool for decision aid in water management practice. Copyright © 2010 John Wiley & Sons, Ltd and ERP Environment. [source] Criteria for the assessment of processes for sustainable river basin management and their congruence with the EU Water Framework DirectiveENVIRONMENTAL POLICY AND GOVERNANCE, Issue 4 2008Beatrice Hedelin Abstract In order to manage the increasing pressure on the world's water resources, new planning methodologies/processes for sustainable river basin management are currently being developed. For such processes to work well, however, the legal context must allow, or support, such processes. In this study, a set of criteria relating to methodologies/processes for sustainable water management is used to assess the EU Water Framework Directive (WFD). The study suggests that the WFD erects few formal barriers to good planning practices. However, planning processes will need to be adapted to compensate for the weak legal support in a number of important areas, namely the use of knowledge from beyond the natural sciences, the use of methodologies for the explicit handling of values and the use of procedures for democratic participation. In so doing the issues identified here provide a basis for systematic thinking about how to design the necessary planning processes. Copyright © 2008 John Wiley & Sons, Ltd and ERP Environment. [source] Do Developing Countries Need a Development Box?EUROCHOICES, Issue 2 2003Jonathan Brooks Summary Do Developing Countries Need a Development Box? Developing country proposals for a Development Box focus on changes to WTO rules on agricultural trade that would enable them to address more effectively their objectives related to food security, poverty alleviation and economic development. Yet, there are few instances where developing countries have been constrained in the policies they can adopt. This does not mean that demands for a Development Box are pointless, for if the next WTO agreement is to have a real impact on rates of protection, there will be a need for tighter commitments in both developed and developing countries. Hence proposals for a Development Box can be seen as an insurance policy, given the prospect of deeper multilateral reforms. There is a strong case for easier access to safeguards, under which developing countries could temporarily apply higher tariffs on food security crops when world prices are depressed below threshold levels. There may be an economic justification for expanding the types of domestic support measures that developing countries can employ, in those rare cases where policies would otherwise be constrained. However, these demands should not constrain progress on the most important issue; namely, how OECD countries can do more for developing countries through improvements in market access, the elimination of explicit and implicit export subsidies, and reductions in trade-distorting domestic support. Faut-il une boite spéciale pour le développement ? Les propositions des pays en développement en vue ?établir une ,boîte pour le développement'à,OMC sont centrées sur ,idée qu'il convient de modifier les règies du commerce international agricole, afin de leur permettre ?aborder de façon plus efflcace leurs problèmes spécifiques de sécurité alimentaire, de réduction de la pauvreté et de développement économique. Pourtant, il existe peu ?exemples de situations dans lesquelles un pays en développement ait pu être gêné dans ,adoption ?une politique particulière. Cela ne veut pas dire qu'une boîte pour le développement soit inutile: si le prochain accord à,OMC doit avoir un effet réel sur les taux de protection, des engagements encore plus stricts seront nécessaires de la part, aussi bien des pays en développement que des pays développés. II en résulte que les propositions en vue ?une ,boîte pour le développement' peuvent être considérées comme une politique ?assurance, dans ,optique de réformes multilatérales plus approfondies. II y a des raisons sérieuses pour faciliter le recours aux clauses de sauvegarde, grâce auxquelles les pays en développement pourraient imposer temporairement des droits plus élevés sur les denrées importantes pour leur sécurité alimentaire lorsque les cours mondiaux descendent en deçà?un certain seuil. Il peut exister une justification économique à,extension des catégories de soutien que les pays en développement peuvent employer, dans les cas peu fréquents où les engagements pris seraient contraignants à cet égard. Mais surtout, il faut que les pays en développement prennent garde à ne pas entraver les progrès dans les domaines vraiment importants, à savoir ce que les pays de ,OCDE peuvent faire pour eux en améliorant ,accès aux marchés, en eliminant les subventions implicites et explicites aux exportations, et en réduisant les mesures de soutien intérieures qui affectent les échanges. Benötigen Entwicklungsländer eine Development Box? Die Vorschläge der Entwicklungsländer für eine Development Box zielen auf Änderungen in den Agrarhandelsvorschriften der WTO ab; es soil ihnen ermöglicht werden, ihre Zdele hinsichtlich der Nahrungsmt-telsicherheit, Armutsbekämpfung und Wirtschaftsentwicklung wirkungsvoller zu verfolgen. Bis heute jedoch wurden die Entwicklungsländer nur in wenigen Fällen bei der Ausgestaltung bestimmter Politikmaßnahmen eingeschränkt. Damit ist nicht gesagt, dass Forderungen nach einer Development Box zwecklos sind, denn wenn sich das kommende WTO-Abkommen tatsächlich auf die Protektionsraten auswirken soil, werden sowohl den entwickelten Ländern als auch den Entwicklungsländern mehr Verpflichtungen abverlangt werden. Daher können Vorschläge für eine Development Box als eine Versicherungspolirik vor dem Hintergrund der Aussicht auf tiefergreifende multilaterale Reformen angesehen werden. Es spricht vieles für einen einfacheren Zugang zu Schutzmaßnahmen, unter denen Entwicklungsländer vorübergehend höhere Zölle auf pflanzliche Erzeugnisse mit Bedeutung für die Nahrungsmittelsicherheit erheben könnten, wenn die Weltpreise unterhalb von Schwellenwerten liegen. Es mag aus ökonomischer Sicht eine Rechtfertigung für die Ausdehnung der inlandischen marktstützenden Maßnahmen geben, welche Entwicklungsländer anwenden dürfen; dies kann sinnvoll sein, wenn andernfalls, allerdings in seltenen Fällen, Politikmaßnahmen eingeschränkt werden müssten. Diese Forderungen sollten den Fortschritt bei den allerwichtigsten Themen jedoch nicht behindern; OECD-Länder können mehr für Entwicklungsländer tun, und zwar durch Verbesserung des Marktzugangs, durch die Abschaffung von expliziten und impliziten Exportsubventionen und durch Kürzungen bei den handelsverzerrenden Inlandssubventionen. [source] Qualifications Frameworks: some conceptual issuesEUROPEAN JOURNAL OF EDUCATION, Issue 4 2007MICHAEL YOUNG The aim of this article is to contribute to realising the progressive and democratic opportunities that National Qualifications Frameworks (NQFs) can offer. In doing so it will be critical of many of the ways that NQFs have been interpreted to date and the claims that have been made for them. The article has six sections. Section 1 considers some of the reasons for the recent growth of interest in NQFs. Section 2 is concerned with the widely shared goals of NQFs and some of the contradictions and problems that they involve. Section 3 discusses the very different forms that NQFs can take. Section 4 examines a number of issues that underlie all approaches to qualifications but are made more explicit by qualification frameworks and concludes by questioning the much lauded claim that NQFs can promote and accredit informal learning. The concluding section considers the longer term implications for the future of NQFs of the earlier analysis. [source] Disrupting basolateral amygdala function impairs unconditioned freezing and avoidance in ratsEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 4 2001Almira Vazdarjanova Abstract Lesions of the lateral/basolateral amygdala nuclei (BLC) disrupt freezing behaviour in response to explicit or contextual cues (conditioned stimuli , CS) paired previously with footshock (unconditioned stimulus). This deficit in expression of defensive behaviour in response to conditioned stimuli is often interpreted as inability of lesioned rats to learn CS,US associations. However, findings of several studies indicate that BLC-lesioned rats can rapidly learn CS,US associations. Such findings suggest that lesioned rats can learn CS,US associations but are impaired in the expression of freezing behaviour. In the present study we report that both temporary inactivation (lidocaine) and permanent excitotoxic (NMDA) lesions of the BLC impair the unconditioned freezing and avoidance behaviours of rats in response to a novel fear-eliciting stimulus, a ball of cat hair. These findings suggest that the BLC influences the expression of freezing and avoidance behaviours, and/or that it potentiates rats' experience of fear. Along with prior evidence of spared memory for aversive learning after BLC lesions, these findings suggest that disrupted freezing to conditioned cues in BLC-lesioned rats does not necessarily reflect inability to form CS,US associations. [source] Understanding and using the implicit association test: V. measuring semantic aspects of trait self-conceptsEUROPEAN JOURNAL OF PERSONALITY, Issue 8 2008Konrad Schnabel Abstract Implicit Association Tests (IATs) often reveal strong associations of self with positive rather than negative attributes. This poses a problem in using the IAT to measure associations involving traits with either positive or negative evaluative content. In two studies, we employed non-bipolar but evaluatively balanced Big Five traits as attribute contrasts and explored correlations of IATs with positive (e.g. sociable vs. conscientious) or negative (e.g. reserved vs. chaotic) attributes. Results showed (a) satisfactory internal consistencies for all IATs, (b) explicit,explicit and implicit,implicit correlations that were moderate to high and comparable in strength after both were corrected for attenuation and (c) better model fit for latent variable models that linked the implicit and explicit measures to distinct latent factors rather to the same factor. Together, the results suggest that IATs can validly assess the semantic aspect of trait self-concepts and that implicit and explicit self-representations are, although correlated, also distinct constructs. Copyright © 2008 John Wiley & Sons, Ltd. 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