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Rational
Terms modified by Rational Selected AbstractsIS EDUCATIONAL POLICY MAKING RATIONAL , AND WHAT WOULD THAT MEAN, ANYWAY?EDUCATIONAL THEORY, Issue 5 2009Eric Bredo In Moderating the Debate: Rationality and the Promise of American Education, Michael Feuer raises concerns about the consequences of basing educational policy on the model of rational choice drawn from economics. Policy making would be better and more realistic, he suggests, if it were based on a newer procedural model drawn from cognitive science. In this essay Eric Bredo builds on Feuer's analysis by offering a more systematic critique of the traditional model of rationality that Feuer criticizes, a more critical evaluation of the procedural model that he favors, and a recommendation that the situational model he does not consider may have some benefits over both. This analysis shows that the traditional model presupposes an actor that cannot learn or develop. While the actor in the procedural model can learn, Bredo contends that it cannot develop, that is, it cannot outgrow its initial assumptions and values. Only the situational model allows for learning and development, important in a model to be used in the field of education. Bredo also considers in his analysis the social-relational assumptions built into the traditional, procedural, and situational models and the likely ethical consequences of acting on them. [source] Rational, Facile Synthesis and Characterization of the Neutral Mixed-Metal Organometallic Oxides Cp*2MoxW6,xO17 (Cp* = C5Me5, x = 0, 2, 4, 6)EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 34 2009Gülnur Taban-Çal Abstract The reaction of the bis(pentamethylcyclopentadienyl)pentaoxidodimetal complexes Cp*2M2O5 with four equivalents of Na2M,O4 (M, M, = Mo, W) in acidic aqueous medium constitutes a soft and selective entry into neutral Lindqvist-type organometallic mixed-metal oxides Cp*2MoxW6,xO17 [x = 6 (1), 4 (2), 2 (3), 0 (4)]. The identity of the complexes is demonstrated by elemental analyses, thermogravimetric analyses and infrared spectroscopy. Thermal degradation of 1,4 up to above 500 °C leads to Mox/6W1,x/6O3. The molecular identity and geometry of compound 2 is further confirmed by a fit of the powder X-ray diffraction pattern with a model obtained from previously reported single-crystal X-ray structures of 1 and 4, with which 2 is isomorphous. DFT calculations on models obtained by replacing Cp* with Cp (I,IV) validate the structural assignments and assist in the assignment of the M,M,,O vibrations. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Rational and irrational aspects of countertransferenceJOURNAL OF CLINICAL PSYCHOLOGY, Issue 8 2001Albert Ellis Countertransference in therapy stems from biological tendencies and social learning influences that involve mild or heavy prejudiced thinking, feeling, and behaving. Several reasons are given why it is almost inevitable and has both beneficial and destructive aspects,not either/or but both/and. It is hypothesized that therapists can well make good use of countertransference if they strive to employ it in a preferential, experimental rather than an absolutist musturbating manner. © 2001 John Wiley & Sons, Inc. J Clin Psychol/In Session 57: 999,1004, 2001. [source] The effect of lack of insurance, poverty and paediatrician supply on immunization rates among children 19,35 months of age in the United StatesJOURNAL OF EVALUATION IN CLINICAL PRACTICE, Issue 2 2008James L. Becton Jr MD Rational, aims and objectives, Previous studies found that the increasing number of paediatricians in the United States was associated with improved childhood immunization coverage, while the increasing poverty level and the lack of health insurance reduced access to health care. We evaluated whether changes in the number of paediatricians, poverty level and health insurance affected national childhood immunization coverage in the state levels of the United States. Methods, Data were collected primarily from the US National Immunization Surveys, series 4:3:1:3:3 from years 1995 and 2003. Ordinal logistic regression analysis was used to analyse the relationships among variables. Results, Over 8 years studied, immunization coverage increased for children aged 19,35 months from 52.3% to 79.8% in the 50 states. The average number of paediatricians per 1000 births increased 28.7% while the percentage of children without health insurance declined 15.6%, and the percentage of children who lived in poverty level declined 17.3%. In 1995, the states with higher immunization coverage were associated with higher numbers of paediatricians [odds ratio (OR), 32.73; 95% confidence interval (CI), 5.96,179.77]. In 2003, the higher numbers of paediatricians still played a role in the increased immunization coverage (OR, 4.69; 95% CI, 1.01,21.78); however, the higher rate of uninsured children in 2003 had an even greater effect upon immunization coverage. Compared with states with lower rates of uninsured children, states with intermediate and higher rates of uninsured children had sixfold (OR, 0.16; 95% CI, 0.03,0.81) and 16-fold (OR, 0.06; 95% CI, 0.01,0.40) decreased childhood immunization coverage, respectively. Conclusion, Between 1995 and 2003 in the United States, the lack of health insurance became more prominent than the supply of paediatricians in affecting immunization coverage for children aged 19,35 months. Future improvements in insurance coverage for children will likely lead to greater immunization coverage. [source] Clearly Irrational Financial Market Behavior: Evidence from the Early Exercise of Exchange Traded Stock OptionsTHE JOURNAL OF FINANCE, Issue 1 2003Allen M. Poteshman This paper analyzes the early exercise of exchange-traded options by different classes of investors over the 1996 to 1999 period. A large number of exercises are identified as clearly irrational without invoking any model of market equilibrium. Customers of discount brokers and customers of full-service brokers both engage in a significant number of irrational exercises while traders at large investment houses exhibit no irrational early exercise behavior. Rational and irrational exercise is triggered for discount and full-service customers by the underlying stock price attaining its highest level over the past year and by high returns on the underlying stock. [source] Differential Classification of Acute Myocardial Infarction into ST- and Non-ST Segment Elevation Is Not Valid or RationalANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 3 2010Brendan Phibbs M.D., F.A.C.C. Background: The distinction between ST elevation and nonST elevation infarcts is widely accepted and is employed as a guide to management. Aim: This is review of the world literature to assess the basis for this distinction, since the two studies on which it is based are seriously flawed in method and conclusions. Method: Pathologic and clinical studies were reviewed from the world literature. Finding: The pathology of the two subsets is identical as are the morbidity, mortality and clinical course. Non-ST elevation infarcts are likely to be subsequent, to occur in older patients and to involve the circumflex artery: this subset therefore includes a high-risk group. ST deviation in any part of the electric field of the heart will predictably be accompanied by reciprocal deviation if the entire field of the heart is mapped. Further, ST deviation of infarction is often transient, resolving in minutes so that infarcts will be predictably misclassified. ST deviation per se is therefore not a rational basis for classification of infarcts. In fact, invasive therapy is indicated in both subsets with identical results. Conclusion: The distinction between ST elevation and non-ST elevation infarcts is baseless. The high risk subgroup included in the non-ST elevation infarct set should not be denied the benefit of early invasive therapy. Ann Noninvasive Electrocardiol 2010;15(3):191,199 [source] II,Reflections on the Reasonable and the Rational in Conflict ResolutionARISTOTELIAN SOCIETY SUPPLEMENTARY VOLUME, Issue 1 2009Ruth Chang Most familiar approaches to social conflict moot reasonable ways of dealing with conflict, ways that aim to serve values such as legitimacy, justice, morality, fairness, fidelity to individual preferences, and so on. In this paper, I explore an alternative approach to social conflict that contrasts with the leading approaches of Rawlsians, perfectionists, and social choice theorists. The proposed approach takes intrinsic features of the conflict,what I call a conflict's evaluative ,structure',as grounds for a rational way of responding to that conflict. Like conflict within a single person, social conflict can have a distinctive evaluative structure that supports certain rational responses over others. I suggest that one common structure in both intra- and interpersonal cases of conflict supports the rational response of ,self-governance'. Self-governance in the case of social conflict involves a society's deliberating over the question, ,What kind of society should we be?' In liberal democracies, this rational response is also a reasonable one. [source] Rational `correction' of the amino-acid sequence of RbcX protein from the thermophilic cyanobacterium Thermosynechococcus elongatus dramatically improves crystallizationACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 9 2008Miroslaw Tarnawski RbcX is a dimeric protein found in cyanobacteria that assists in the assembly of the oligomeric RuBisCO complex. RbcX from the thermophile Thermosynechococcus elongatus (TeRbcX) contains an unusual Cys103 residue in its sequence and when expressed recombinantly the protein aggregates and cannot be crystallized. Site-directed mutagenesis of Cys103 to either Arg or Ala produced non-aggregating proteins that could be readily crystallized in several crystal forms. Synchrotron-radiation X-ray diffraction data were collected to 1.96,Å resolution and formed the basis of crystal structure analysis of TeRbcX. [source] Is it Rational to Vote?BRITISH JOURNAL OF POLITICS & INTERNATIONAL RELATIONS, Issue 3 2005Five Types of Answer, a Suggestion First page of article [source] Human Symbol Manipulation Within an Integrated Cognitive ArchitectureCOGNITIVE SCIENCE - A MULTIDISCIPLINARY JOURNAL, Issue 3 2005John R. Anderson Abstract This article describes the Adaptive Control of Thought,Rational (ACT,R) cognitive architecture (Anderson et al., 2004; Anderson & Lebiere, 1998) and its detailed application to the learning of algebraic symbol manipulation. The theory is applied to modeling the data from a study by Qin, Anderson, Silk, Stenger, & Carter (2004) in which children learn to solve linear equations and perfect their skills over a 6-day period. Functional MRI data show that: (a) a motor region tracks the output of equation solutions, (b) a prefrontal region tracks the retrieval of declarative information, (c) a parietal region tracks the transformation of mental representations of the equation, (d) an anterior cingulate region tracks the setting of goal information to control the information flow, and (e) a caudate region tracks the firing of productions in the ACT,R model. The article concludes with an architectural comparison of the competence children display in this task and the competence that monkeys have shown in tasks that require manipulations of sequences of elements. [source] An Activation-Based Model of Sentence Processing as Skilled Memory RetrievalCOGNITIVE SCIENCE - A MULTIDISCIPLINARY JOURNAL, Issue 3 2005Richard L. Lewis Abstract We present a detailed process theory of the moment-by-moment working-memory retrievals and associated control structure that subserve sentence comprehension. The theory is derived from the application of independently motivated principles of memory and cognitive skill to the specialized task of sentence parsing. The resulting theory construes sentence processing as a series of skilled associative memory retrievals modulated by similarity-based interference and fluctuating activation. The cognitive principles are formalized in computational form in the Adaptive Control of Thought,Rational (ACT,R) architecture, and our process model is realized in ACT,R. We present the results of 6 sets of simulations: 5 simulation sets provide quantitative accounts of the effects of length and structural interference on both unambiguous and garden-path structures. A final simulation set provides a graded taxonomy of double center embeddings ranging from relatively easy to extremely difficult. The explanation of center-embedding difficulty is a novel one that derives from the model' complete reliance on discriminating retrieval cues in the absence of an explicit representation of serial order information. All fits were obtained with only 1 free scaling parameter fixed across the simulations; all other parameters were ACT,R defaults. The modeling results support the hypothesis that fluctuating activation and similarity-based interference are the key factors shaping working memory in sentence processing. We contrast the theory and empirical predictions with several related accounts of sentence-processing complexity. [source] Strategies in Human Nonmonotonic ReasoningCOMPUTATIONAL INTELLIGENCE, Issue 3 2000Marilyn Ford Although humans seem adept at drawing nonmonotonic conclusions, the nonmonotonic reasoning systems that researchers develop are complex and do not function with such ease. This paper explores people's reasoning processes in nonmonotonic problems. To avoid the problem of people's conclusions being based on knowledge rather than on some reasoning process, we developed a scenario about life on another planet. Problems were chosen to allow the systematic study of people's understanding of strict and nonstrict rules and their interactions. We found that people had great difficulty reasoning and we identified a number of negative factors influencing their reasoning. We also identified three positive factors which, if used consistently, would yield rational and coherent reasoning,but no subject achieved total consistency. (Another possible positive factor, specificity, was considered but we found no evidence for its use.) It is concluded that nonmonotonic reasoning is hard. When people need to reason in a domain where they have no preconceived ideas, the foundation for their reasoning is neither coherent nor rational. They do not use a nonmonotonic reasoning system that would work regardless of content. Thus, nonmonotonic reasoning systems that researchers develop are expected to do more reasoning than humans actually do! [source] Learning from Difference: Considerations for Schools as CommunitiesCURRICULUM INQUIRY, Issue 3 2000Carolyn M. Shields In today's highly complex and heterogeneous public schools, the current notion of schools as homogeneous communities with shared beliefs, norms, and alues is inadequate. Drawing on Barth's (1990) question of how to use ifference as a resource, I take up ideas from feminism, multiculturalism, and inclusive education to consider the development of community in schools. I argue that despite the valuable contributions of these theoretical perspectives, each lso includes the potential for increased fragmentation and polarization. As we consider how to use differences as a foundation for community, it is important ot to reify any particular perspective, thus marginalizing others and erecting new barriers. Explicitly embracing the need to identify and respect difference, being open to new ideas without taking an exclusionary position, and committing to ongoing participation in dialogical processes may help schools to develop as more authentic communities of difference. Among the dominant issues identified in today's climate of turbulent educational reform are concerns about how to restructure schools to ensure equality of student opportunity and excellence of instruction (Elmore, 1990; Lieberman, 1992; Murphy, 1991). Many proposals include modifying present leadership and governance structures, overcoming the hegemony of existing power bases, developing mechanisms for accountability, enhancing professionalism, and co-ordinating community resources. One of the suggestions frequently made to address these issues is to change from a focus on schools as organizations to a recognition of schools as communities (Barth, 1990; Fullan, 1993; Lupart & Webber, 1996; Senge, 1990). However, despite the widespread use of the metaphor of community as an alternative to the generally accepted concept of schools as rational or functional organizations, there seems to be little clarity about the concept of community, what it might look like, how it might be implemented, or what policies might sustain it. Indeed, theories about schools as communities have often drawn from Tönnies (1887/1971) concept of gemeinschaft,a concept which perhaps evokes a more homogeneous and romanticized view of the past than one which could be helpful for improving education in today's dynamic, complex, and heterogeneous context (Beck & Kratzer, 1994; Sergiovanni, 1994a). More recently, several writers (Fine et al., 1997; Furman, 1998; Shields & Seltzer, 1997) have advanced the notion of communities of otherness or difference. These authors have suggested that rather than thinking of schools as communities that exist because of a common affiliation to an established school ethos or tradition, it might be more helpful to explore an alternative concept. A school community founded on difference would be one in which the common centre would not be taken as a given but would be co-constructed from the negotiation of disparate beliefs and values as participants learn to respect, and to listen to, each other. In this concept, bonds among members are not assumed, but forged, and boundaries are not imposed but negotiated. Over the past eight years, as I have visited and worked with a large number of schools trying earnestly to address the needs of their diverse student bodies, I have become increasingly aware of the limitations of the concept of community used in the gemeinschaft sense with its emphasis on shared values, norms, and beliefs, and have begun to reflect on the question framed by Barth (1990): ,How can we make conscious, deliberate use of differences in social class, gender, age, ability, race, and interest as resources for learning?' (p. 514). In this article, I consider how learning from three of these areas of difference: gender, race, and ability, may help us to a better understanding of educational community. This article begins with some illustrations and examples from practice, moves to consider how some theoretical perspectives may illuminate them, and concludes with reflections on how the implications of the combined reflections on practice and theory might actually help to reconceptualize and to improve practice. While it draws heavily on questions and impressions which have arisen out of much of my fieldwork, it is not intended to be an empirical paper, but a conceptual one,one which promotes reflection and discussion on the concept of schools as communities of difference. The examples of life in schools taken from longitudinal research studies in which I have been involved demonstrate several common ways in which difference is dealt with in today's schools and some of the problems inherent in these approaches. Some ideas drawn from alternative perspectives then begin to address Barth's question of how to make deliberate use of diversity as a way of thinking about community. Taken together, I hope that these ideas will be helpful in creating what I have elsewhere called ,schools as communities of difference' (Shields & Seltzer, 1997). [source] The Explainability of IntuitionsDIALECTICA, Issue 1 2004Nenad Mi Explaining intuitions in terms of "facts of our natural history" is compatible with rationally trusting them. This compatibilist view is defended in the present paper, focusing upon nomic and essentialist modal intuitions. The opposite, incompatibilist view alleges the following: If basic modal intuitions are due to our cognitive make-up or "imaginative habits" then the epistemologists are left with a mere non-rational feeling of compulsion on the side of the thinker. Intuitions then cannot inform us about modal reality. In contrast, the paper argues that there are several independent sources of justification which make the feeling of compulsion rational: the prima-facie and a priori ones come from the obviousness of our basic modal intuitions and our not being able to imagine things otherwise, others, a posteriori, from the epistemic success of these intuitions. Further, the general scheme of evolutionary learning is reliable, reliability is preserved in the resulting individual's cognitive make-up, and we can come to know this a posteriori. The a posteriori appeal to evolution thus plays a subsidiary role in justification, filling the remaining gap and removing the residual doubt. Explaining modal intuitions is compatible with moderate realism about modality itself. [source] Rapid humanitarian assessments and rationality: a value-of-information study from Iraq, 2003-04DISASTERS, Issue 1 2007Aldo Benini Rapid assessments are one of the standard informational tools in humanitarian response and are supposed to contribute to rational decision-making.1 The extent to which the assessment organisation itself behaves rationally, however, is an open question. This can be evaluated against multiple criteria, such as the cost and value of the information it collects and its ability to adapt flexibly design or samples when the survey environment changes unforeseeably. An unusual data constellation from two concurrent recent (2003,04) rapid assessments in northern Iraq permits us to model part of the actual assessment behaviour in terms of geographical, community and prior substantive information attributes. The model correctly predicts the decisions, in 79 per cent of the 2,425 local communities in focus, that data collector teams in the Emergency Mine Action Survey made to visit or not to visit. The analysis demonstrates variably rational behaviour under conditions of insecurity, repeated regrouping and incomplete sampling frames. A pronounced bias towards very small rural settlements is irrational for the overall results, but may be a rational strategy of individual survey workers seeking to prolong their employment. Implications for future assessments are sketched in the areas of tools for urban surveys, greater adaptability, including early feedback from users, and sensibility to value-of-information concepts. [source] Neuroprotection in emerging psychotic disordersEARLY INTERVENTION IN PSYCHIATRY, Issue 2 2007Gregor Berger Abstract Aim:, The emerging phase of psychotic disorders is pleomorphic and fluctuates in presentation. Hence, from a clinical perspective, treatment modalities are often unclear. This paper investigates the rational and potential use of neuroprotective agents in emerging psychotic disorders. Methods:, Medline databases were searched from 1966 to 2006 followed by the cross-checking of references using following keywords: neuroprotection, apoptosis, natural cell death, neurodevelopment, plasticity, neurogenesis, combined with brain and schizophrenia. Results:, Agents such as atypical antipsychotics, antidepressants, omega-3 fatty acids, modulators of glutamateric neurotransmission (e.g. ampakines, glycine, memantine), erythropoietin, N -acetylcysteine, COX-2 inhibitors or antioxidants have neuroprotective (anti-apoptotic) properties and may therefore be able to protect brain maturational processes disturbed in emerging psychotic disorders. Clinical trials suggest that atypical antipsychotics, antidepressants, omega-3 fatty acids and low-dose lithium as sole treatments were able to improve symptoms and functioning, and delay or in some cases even prevent the onset of frank psychosis. Initially these substances have been chosen because they have been used either as sole or augmentation treatments in established psychotic disorders. However, chronicity and already effective treatments may overshadow their potential clinical use in emerging (prodromal) psychosis. Conclusion:, Neuroprotection as a new treatment paradigm for at-risk mental states seems to be promising and pilot data are suggestive that more benign interventions may already be sufficient to delay or even prevent the onset of frank psychosis. A coordinated research effort will be necessary to address the question which agents should be used under which circumstances. [source] On the accuracy of simplified methods for the analysis of isolated bridgesEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 3 2001P. Franchin Abstract To foster the use of seismic isolation in structures, existing guidelines strive to formulate design methods which are simple and accessible to non-specialized engineers. On the other hand, not all of the simplifying provisions adopted by the norms can be said to have been adequately tested to provide a consistent level of accuracy. The study attempts, in particular, to elucidate three aspects related to the methods of analysis for linear or linearized isolated bridges on which little or no advice can be found in the norms. The first one is about the way one has to account for the fact that damping matrices of isolated bridges are never of proportional type. The present study demonstrates, through a number of typical applications, that classical modal analysis, using real modes and the diagonal terms of the modal damping matrices, still provide a fully acceptable approximation. The second and third aspects are related to the use of linearization expressions extended to the analysis of hyperstatic bridges. Parametric analyses conducted in the study show that none of the formulas in current use gives satisfactory results for both the displacement and the force responses, a requirement for a reliable design of an isolated bridge. How to use the equivalent linear parameters, and in particular the isolators equivalent damping ratios, in the context of a modal analysis, is treated next. This problem is seldom if ever mentioned in the norms where at most a formula is given for constructing modal damping ratios based on the damping ratios of the isolators. A rational, approximate procedure is discussed in this paper, applicable to all types of structures with non-proportional damping, which in the case of bridges can be shown to reduce to the expression provided in the Japanese bridge design guidelines. Copyright © 2001 John Wiley & Sons, Ltd. [source] Restraining the Genuine Homo Economicus: Why the Economy Cannot Be Divorced from Its GovernanceECONOMICS & POLITICS, Issue 2 2003Stergios Skaperdas The Homo economicus of traditional economics is far from being completely self-interested, rational, or as individualistic as he is purported to be; he will haggle to death over price but will not take what he wants by force. Implicitly, he is assumed to behave ruthlessly within a well-defined bubble of sainthood. Based on a simple model, I first examine what occurs when this assumption is relaxed and genuine, amoral Homo economici interact. Productivity can be inversely related to compensation; a longer shadow of the future can intensify conflict; and more competition among providers of protection reduces welfare. The patently inefficient outcomes that follow call for restraining self-interest, for finding ways to govern markets. I then review some of the different ways of creating restraints, from the traditional social contract, to the hierarchical domination of kings and lords, to modern forms of governance. Checks and balances, wider representation, the bureaucratic form of organization, and other ingredients of modern governance can partly be thought of as providing restraints to the dark side of self-interest. Though highly imperfect, these restraints are better than the alternative, which typically involves autocratic, amateurish, and corrupt rule. Then, thinking of most problems in terms of a first-best economic model is practically and scientifically misguided. [source] Campaign War Chests, Entry Deterrence, and Voter RationalityECONOMICS & POLITICS, Issue 3 2002Dhammika Dharmapala It is often claimed that the accumulation of "war chests" by incumbents deters entry by high,quality challengers in Congressional elections. This paper presents a game,theoretic analysis of the interaction between an incumbent, potential challengers, an interest group, and a representative (rational) voter, where the incumbent's "quality" (or "legislative effectiveness") is known to the interest group, but not to the voter or to potential challengers. Under certain conditions, a perfectly revealing equilibrium exists; the incumbent signals her quality by raising funds from the interest group to accumulate a war chest. The entry deterrence effect thus operates solely through the role of war chests in signaling incumbent quality. [source] Activist Macroeconomic Policy, Election Effects and the Formation of Expectations: Evidence from OECD EconomiesECONOMICS & POLITICS, Issue 2 2000David Kiefer We examine the explanatory power of a political,business cycle theory in which governments practice short-run policy to lessen the impact of exogenous shocks. Governments have ideological objectives with respect to macroeconomic performance, but are constrained by an augmented Phillips curve. The most prominent version, the rational partisan model, incorporates forward-looking expectations. This model can be compared to a competing model based on backward-looking expectations. Alesina and Roubini's recent advocacy of the rational model uses OECD data. Our reconsideration of the same data, updated to 1995, suggests that the adaptive expectations version offers a better explanation than the rational one. [source] Child-Rearing: On government intervention and the discourse of expertsEDUCATIONAL PHILOSOPHY AND THEORY, Issue 6 2008Paul Smeyers Abstract For Kant, education was understood as the ,means' to become human,and that is to say, rational. For Rousseau by contrast, and the many child-centred educators that followed him, the adult world, far from representing reason, is essentially corrupt and given over to the superficialities of worldly vanity. On this view, the child, as a product of nature, is essentially good and will learn all she needs to know from experience. Both positions have their own problems, but beyond this ,internal debate', the change in the content of education (i.e. child-rearing and schooling) is now furthermore due to a radical pluralism that has swept the world. Moreover, there may be differences in value between individual parents and between values held within the family and those held in society at large. Among other reasons this has put more generally children's (and parents') ,rights' on the agenda, which differs from thinking of education in terms of a ,practice'. The paper develops this latter concept and the criticisms to which it has been subject and argues that there is no necessary incompatibility between initiation into an existing practice and transforming that practice in some way, if it is emphasized how practices are learned and enacted. It then turns to the tendency in education and child-rearing, as in other spheres of human interaction, for more laws and codes of conduct and to call upon experts for all kind of matters. It argues that performativity rules on the level of the practitioner, of the experts, and even on the level of educational research. It argues that many governments have adopted in matters of schooling the language of output and school effectiveness and that something similar is now bound to happen in the sphere of child-rearing (with talk of parenting skills and courses). This is made credible due to a particular model of educational research, i.e. an empiricist quasi-causal model of explaining human behaviour. The paper then discusses the problems with this stance and argues that we should part company from the entrepreneurial manipulative educator to open up a sphere of responsiveness for the child and that for these reasons, the concept of the ,practice of child-rearing' should be revisited. Insisting on the complexities that have to be taken into account and thus surpassing a discourse of effectiveness and output as well as of codes of conduct and rulings of courts of law, may help us to focus on what is really at stake: to lead a meaningful life, to be initiated into what is ,real for us' and what we value. It concludes that thus restoring a place for child-rearing as a practice will do justice to the responsiveness to which each child is entitled. [source] Engineered Pyranose 2-Oxidase: Efficiently Turning Sugars into Electrical EnergyELECTROANALYSIS, Issue 7-8 2010Oliver Spadiut Abstract Due to the recent interest in enzymatic biofuel cells (BFCs), sugar oxidizing enzymes other than the commonly used glucose oxidase are gaining more importance as possible bioelements of implantable microscale-devices, which can, for example, be used in biosensors and pacemakers. In this study we used rational and semi-rational protein design to improve the catalytic activity of the enzyme pyranose 2-oxidase (P2Ox) with its alternative soluble electron acceptors 1,4-benzoquinone and ferricenium ion, which can serve as electron mediators, to possibly boost the power output of enzymatic BFCs. Using a screening assay based on 96-well plates, we identified the variant H450G, which showed lower KM and higher kcat values for both 1,4-benzoquinone and ferricenium ion compared to the wild-type enzyme, when either D -glucose or D -galactose were used as saturating electron donors. Besides this variant, we analyzed the variants V546C and T169G/V546C for their possible application in enzymatic BFCs. The results obtained in homogeneous solution were compared with those obtained when P2Ox was immobilized on the surface of graphite electrodes and either "wired" to an osmium redox polymer or using soluble 1,4-benzoquinone as mediator. According to the spectrophotometrically determined kinetic constants, the possible energy output, measured in flow injection analysis experiments with these variants, increased up to 4-fold compared to systems employing the wild-type enzyme. [source] Developing limits for driving under cannabisADDICTION, Issue 12 2007Franjo Grotenhermen ABSTRACT Objective Development of a rational and enforceable basis for controlling the impact of cannabis use on traffic safety. Methods An international working group of experts on issues related to drug use and traffic safety evaluated evidence from experimental and epidemiological research and discussed potential approaches to developing per se limits for cannabis. Results In analogy to alcohol, finite (non-zero) per se limits for delta-9-tetrahydrocannabinol (THC) in blood appear to be the most effective approach to separating drivers who are impaired by cannabis use from those who are no longer under the influence. Limited epidemiological studies indicate that serum concentrations of THC below 10 ng/ml are not associated with an elevated accident risk. A comparison of meta-analyses of experimental studies on the impairment of driving-relevant skills by alcohol or cannabis suggests that a THC concentration in the serum of 7,10 ng/ml is correlated with an impairment comparable to that caused by a blood alcohol concentration (BAC) of 0.05%. Thus, a suitable numerical limit for THC in serum may fall in that range. Conclusions This analysis offers an empirical basis for a per se limit for THC that allows identification of drivers impaired by cannabis. The limited epidemiological data render this limit preliminary. [source] Asymptotic Back Strain Approach for Estimation of Effective Properties of Multiphase MaterialsADVANCED ENGINEERING MATERIALS, Issue 1-2 2007A. Gusev Estimation of the effective properties of composite materials from those of the constituents and the material's morphology is a classical problem of both theoretical and technological interest. In this work, the authors have introduced an asymptotic back strain finite element approach for numerical estimation of effective properties of multiphase materials. The proposed approach should open an appealing pathway to rational and effective computer aided design of random microstructure composite materials. [source] Improving thermostability and catalytic activity of pyranose 2-oxidase from Trametes multicolor by rational and semi-rational designFEBS JOURNAL, Issue 3 2009Oliver Spadiut The fungal homotetrameric flavoprotein pyranose 2-oxidase (P2Ox; EC 1.1.3.10) catalyses the oxidation of various sugars at position C2, while, concomitantly, electrons are transferred to oxygen as well as to alternative electron acceptors (e.g. oxidized ferrocenes). These properties make P2Ox an interesting enzyme for various biotechnological applications. Random mutagenesis has previously been used to identify variant E542K, which shows increased thermostability. In the present study, we selected position Leu537 for saturation mutagenesis, and identified variants L537G and L537W, which are characterized by a higher stability and improved catalytic properties. We report detailed studies on both thermodynamic and kinetic stability, as well as the kinetic properties of the mutational variants E542K, E542R, L537G and L537W, and the respective double mutants (L537G/E542K, L537G/E542R, L537W/E542K and L537W/E542R). The selected substitutions at positions Leu537 and Glu542 increase the melting temperature by approximately 10 and 14 °C, respectively, relative to the wild-type enzyme. Although both wild-type and single mutants showed first-order inactivation kinetics, thermal unfolding and inactivation was more complex for the double mutants, showing two distinct phases, as revealed by microcalorimetry and CD spectroscopy. Structural information on the variants does not provide a definitive answer with respect to the stabilizing effects or the alteration of the unfolding process. Distinct differences, however, are observed for the P2Ox Leu537 variants at the interfaces between the subunits, which results in tighter association. [source] Engineering the properties of a cold active enzyme through rational redesign of the active siteFEBS JOURNAL, Issue 19 2001Iason Tsigos ,In an effort to explore the effects of local flexibility on the cold adaptation of enzymes, we designed point mutations aiming to modify side-chain flexibility at the active site of the psychrophilic alkaline phosphatase from the Antarctic strain TAB5. The mutagenesis targets were residues Trp260 and Ala219 of the catalytic site and His135 of the Mg2+ binding site. The replacement of Trp260 by Lys in mutant W260K, resulted in an enzyme less active than the wild-type in the temperature range 5,25 °C. The additional replacement of Ala219 by Asn in the double mutant W260K/A219N, resulted in a drastic increase in the energy of activation, which was reflected in a considerably decreased activity at temperatures of 5,15 °C and a significantly increased activity at 20,25 °C. Further substitution of His135 by Asp in the triple mutant W260K/A219N/H135D restored a low energy of activation. In addition, the His135,Asp replacement in mutants H135D and W260K/A219N/H135D resulted in considerable stabilization. These results suggest that the psychrophilic character of mutants can be established or masked by very slight variations of the wild-type sequence, which may affect active site flexibility through changes in various conformational constraints. [source] Working at Intimacy: Gay Men's Workplace FriendshipsGENDER, WORK & ORGANISATION, Issue 1 2008Nick Rumens Despite scholarly efforts to challenge the dualistic stereotype of men as rational and women as emotion experts, academics have paid little attention to the issues that arise when gay and lesbian sexualities are introduced into such debates. This article highlights the heterosexist content of much of the research on gender, emotion and organization, and argues the relevancy of investigating the largely neglected topic of intimacy and friendship in the work lives of gay men. Engaging with feminist, queer and sociological research that examines friendship in the lives of individuals who belong to sexual minority groups, I explore in this study the diversity in the way gay men find and work out intimacy in the context of workplace friendships with other gay men and with heterosexual men and women. The data for this article are drawn from in-depth interviews with ten gay men employed in one UK National Health Service Trust. Study findings problematize conceptualizations of friendships at work as being bereft of intimacy, of little value and clearly distinguishable from business relationships. Dichotomous modes of thinking about the impact of gender and sexuality on intimacy and friendship are also challenged. [source] Managers,The missing link in the reward change processGLOBAL BUSINESS AND ORGANIZATIONAL EXCELLENCE, Issue 2 2005Thomas O. Davenport Driven by economic and regulatory forces, many organizations are making wholesale changes in such employee rewards as equity compensation, retirement plans, and health care benefits. Any change in rewards can affect employee motivation and commitment, and poorly implemented reward change can have disastrous outcomes. Organizations must pay attention to all the factors at play,rational and emotional,by laying a solid foundation for reward change and involving managers throughout the organization. Supervisors and managers play an essential role in building a credible case for change and implementing change in a way that employees see as fair and reasonable. © 2005 Wiley Periodicals, Inc. [source] Deleting ,irrational' responses from discrete choice experiments: a case of investigating or imposing preferences?HEALTH ECONOMICS, Issue 8 2006Emily Lancsar Abstract Investigation of the ,rationality' of responses to discrete choice experiments (DCEs) has been a theme of research in health economics. Responses have been deleted from DCEs where they have been deemed by researchers to (a) be ,irrational', defined by such studies as failing tests for non-satiation, or (b) represent lexicographic preferences. This paper outlines a number of reasons why deleting responses from DCEs may be inappropriate after first reviewing the theory underpinning rationality, highlighting that the importance placed on rationality depends on the approach to consumer theory to which one ascribes. The aim of this paper is not to suggest that all preferences elicited via DCEs are rational. Instead, it is to suggest a number of reasons why it may not be the case that all preferences labelled as ,irrational' are indeed so. Hence, deleting responses may result in the removal of valid preferences; induce sample selection bias; and reduce the statistical efficiency and power of the estimated choice models. Further, evidence suggests random utility theory may be able to cope with such preferences. Finally, we discuss a number of implications for the design, implementation and interpretation of DCEs and recommend caution regarding the deletion of preferences from stated preference experiments. Copyright © 2006 John Wiley & Sons, Ltd. [source] SAFE biopsy: A validated method for large-scale staging of liver fibrosis in chronic hepatitis C,HEPATOLOGY, Issue 6 2009Giada Sebastiani The staging of liver fibrosis is pivotal for defining the prognosis and indications for therapy in hepatitis C. Although liver biopsy remains the gold standard, several noninvasive methods are under evaluation for clinical use. The aim of this study was to validate the recently described sequential algorithm for fibrosis evaluation (SAFE) biopsy, which detects significant fibrosis (,F2 by METAVIR) and cirrhosis (F4) by combining the AST-to-platelet ratio index and Fibrotest-Fibrosure, thereby limiting liver biopsy to cases not adequately classifiable by noninvasive markers. Hepatitis C virus (HCV) patients (2035) were enrolled in nine locations in Europe and the United States. The diagnostic accuracy of SAFE biopsy versus histology, which is the gold standard, was investigated. The reduction in the need for liver biopsies achieved with SAFE biopsy was also assessed. SAFE biopsy identified significant fibrosis with 90.1% accuracy (area under the receiver operating characteristic curve = 0.89; 95% confidence interval, 0.87-0.90) and reduced by 46.5% the number of liver biopsies needed. SAFE biopsy had 92.5% accuracy (area under the receiver operating characteristic curve = 0.92; 95% confidence interval, 0.89-0.94) for the detection of cirrhosis, obviating 81.5% of liver biopsies. A third algorithm identified significant fibrosis and cirrhosis simultaneously with high accuracy and a 36% reduction in the need for liver biopsy. The patient's age and body mass index influenced the performance of SAFE biopsy, which was improved with adjusted Fibrotest-Fibrosure cutoffs. Two hundred two cases (9.9%) had discordant results for significant fibrosis with SAFE biopsy versus histology, whereas 153 cases (7.5%) were discordant for cirrhosis detection; 71 of the former cases and 56 of the latter cases had a Fibroscan measurement within 2 months of histological evaluation. Fibroscan confirmed SAFE biopsy findings in 83.1% and 75%, respectively. Conclusion: SAFE biopsy is a rational and validated method for staging liver fibrosis in hepatitis C with a marked reduction in the need for liver biopsy. It is an attractive tool for large-scale screening of HCV carriers. (HEPATOLOGY 2009.) [source] | ||||||||||||||||||||||||||||||||||