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Sample records for making tough choices

  1. Biofuels: making tough choices

    Vermeulen, Sonja; Dufey, Annie; Vorley, Bill

    2008-02-15

    The jury is still out on biofuels. But one thing at least is certain: serious trade-offs are involved in the production and use of these biomass-derived alternatives to fossil fuels. This has not been lost on the European Union. The year kicked off with an announcement from the EU environment commissioner that it may be better for the EU to miss its target of reaching 10 per cent biofuel content in road fuels by 2020 than to compromise the environment and human wellbeing. The 'decision tree' outlined here can guide the interdependent processes of deliberation and analysis needed for making tough choices in national biofuels development.

  2. How libraries make tough choices in difficult times purposeful abandonment

    Stern, David

    2013-01-01

    Contemporary library managers face the need to make difficult choices regarding resource allocation in the modern business environment. How Libraries Make Tough Choices in Difficult Times is a practical guide for library managers, offering techniques to analyze existing and potential services, implement best practices for maximizing existing resources, and utilize pressing financial scenarios in order to justify making difficult reallocation decisions. The book begins by asking the fundamental questions of why, what, and how, moving on to look at how to manage expectations and report to both a

  3. Tough and easy choices

    Olsen, Søren Bøye; Lundhede, Thomas; Jacobsen, Jette Bredahl

    2011-01-01

    and the best alternative to that. We test this hypothesis using data from two independent Choice Experiments both focusing on nature values. In modelling respondents’ self-reported certainty in choice, we find evidence that the stated level of certainty increases significantly as utility difference in choice......Respondents in Stated Preference studies may be uncertain about their preferences for the good presented to them. Inspired by Wang (J Environ Econ Manag 32:219–232, 1997) we hypothesize that respondents’ stated certainty in choice increases with the utility difference between the alternative chosen...... sets increases. In addition, stated certainty increases with income. Furthermore, there is some evidence that male respondents are inherently more certain in their choices than females, and a learning effect may increase stated certainty. We find evidence of this in the first study where the good...

  4. Socioemotional selectivity theory, aging, and health: the increasingly delicate balance between regulating emotions and making tough choices.

    Löckenhoff, Corinna E; Carstensen, Laura L

    2004-12-01

    After providing an introductory overview of socioemotional selectivity theory, we review empirical evidence for its basic postulates and consider the implications of the predicted cognitive and behavioral changes for physical health. The main assertion of socioemotional selectivity theory is that when boundaries on time are perceived, present-oriented goals related to emotional meaning are prioritized over future-oriented goals aimed at acquiring information and expanding horizons. Such motivational changes, which are strongly correlated with chronological age, systematically influence social preferences, social network composition, emotion regulation, and cognitive processing. On the one hand, there is considerable reason to believe that such changes are good for well-being and social adjustment. On the other hand, the very same motivational changes may limit health-related information-seeking and influence attention, memory, and decision-making such that positive material is favored over negative information. Grounding our arguments in socioemotional selectivity theory, we consider possible ways to tailor contexts such that disadvantages are avoided.

  5. Make Better Food Choices

    10 tips Nutrition Education Series make better food choices 10 tips for women’s health Fruits Grains Dairy Vegetables Protein Make yourself a priority and take time to care for yourself. ChooseMyPlate. gov ...

  6. Making Smart Food Choices

    ... turn JavaScript on. Feature: Healthy Aging Making Smart Food Choices Past Issues / Winter 2015 Table of Contents Everyday ... NIH www.nia.nih.gov/Go4Life Making Smart Food Choices To maintain a healthy weight, balance the calories ...

  7. Making Healthy Choices Easier

    Guldborg Hansen, Pelle; Skov, Laurits Rohden; Lund Skov, Katrine

    2016-01-01

    . However, integration and testing of the nudge approach as part of more comprehensive public health strategies aimed at making healthy choices easier is being threatened by inadequate understandings of its scientific character, relationship with regulation and its ethical implications. This article reviews...... working with or incorporating the nudge approach into programs or policies aimed at making healthy choices easier...

  8. Laboratory Powder Metallurgy Makes Tough Aluminum Sheet

    Royster, D. M.; Thomas, J. R.; Singleton, O. R.

    1993-01-01

    Aluminum alloy sheet exhibits high tensile and Kahn tear strengths. Rapid solidification of aluminum alloys in powder form and subsequent consolidation and fabrication processes used to tailor parts made of these alloys to satisfy such specific aerospace design requirements as high strength and toughness.

  9. Making Choices, Setting Goals

    Skinner, Timothy

    2013-01-01

    Diabetes management and education is very important. The way information is provided influences people's behaviours and thus outcomes. The way information is presented can increase or reduce the individual's ability to make informed decisions about their treatment and influences whether they acti...

  10. Tough Choices or Tough Times: The Report of the New Commission on the Skills of the American Workforce. Revised and Expanded Edition

    Jossey-Bass, An Imprint of Wiley, 2008

    2008-01-01

    "Tough Choices or Tough Times," the report of the New Commission on the Skills of the American Workforce, shows how the dynamics of the global economy will lead to a steady decline in the American standard of living if this country does not undertake the first thorough overhaul of its education system in a century. This new revised and expanded…

  11. Tough luck and tough choices: applying luck egalitarianism to oral health.

    Albertsen, Andreas

    2015-06-01

    Luck egalitarianism is often taken to task for its alleged harsh implications. For example, it may seem to imply a policy of nonassistance toward uninsured reckless drivers who suffer injuries. Luck egalitarians respond to such objections partly by pointing to a number of factors pertaining to the cases being debated, which suggests that their stance is less inattentive to the plight of the victims than it might seem at first. However, the strategy leaves some cases in which the attribution of individual responsibility is appropriate (and so, it seems, is asking people to pick up the tab for their choices). One such case is oral health or significant aspects of this. It is appropriate, the paper argues, to hold people responsible for a number of factors that affect their oral health. A luck egalitarian approach inspired by John Roemer can assess whether people have acted responsibly by comparing their choices to those of their peers. A luck egalitarian approach to oral health would recommend prioritizing scarce resources in a responsibility-weighted queuing system and include copayment and general taxation among its measures of financing. © The Author 2015. Published by Oxford University Press, on behalf of the Journal of Medicine and Philosophy Inc. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  12. Tough Choices.

    Kennedy, Mike

    2002-01-01

    Explores the decision by colleges and universities to outsource or self-operate school services such as food, bookstores, and maintenance. Discusses factors influencing the decision, the pros and cons of outsourcing, and the importance of maintaining the goal of improving operations. (EV)

  13. How to make moral choices.

    Chambers, David W

    2011-01-01

    Moral choice is committing to act for what one believes is right and good. It is less about what we know than about defining who we are. Three cases typical of those used in the principles or dilemmas approach to teaching ethics are presented. But they are analyzed using an alternative approach based on seven moral choice heuristics--approaches proven to increase the likelihood of locating the best course of action. The approaches suggested for analyzing moral choice situations include: (a) identify the outcomes of available alternative courses of action; (b) rule out strategies that involve deception, coercion, reneging on promises, collusion, and contempt for others; (c) be authentic (do not deceive yourself); (d) relate to others on a human basis; (e) downplay rational justifications; (f) match the solution to the problem, not the other way around; (g) execute on the best solution, do not hold out for the perfect one; and (h) take action to improve the choice after it has been made.

  14. Making healthy choices easy choices: the role of empowerment

    Koelen, M.A.; Lindström, B.

    2005-01-01

    An important goal of health promotion is to make it easier for people to make healthy choices. However, this may be difficult if people do not feel control over their environment and their personal circumstances. An important concept in relation to this is empowerment. Health professionals are

  15. Making Healthy Choices Easier: Regulation versus Nudging.

    Hansen, Pelle Guldborg; Skov, Laurits Rohden; Skov, Katrine Lund

    2016-01-01

    In recent years, the nudge approach to behavior change has emerged from the behavioral sciences to challenge the traditional use of regulation in public health strategies to address modifiable individual-level behaviors related to the rise of noncommunicable diseases and their treatment. However, integration and testing of the nudge approach as part of more comprehensive public health strategies aimed at making healthy choices easier are being threatened by inadequate understandings of its scientific character, its relationship with regulation, and its ethical implications. This article reviews this character and its ethical implication with a special emphasis on the compatibility of nudging with traditional regulation, special domains of experience, and the need for a more nuanced approach to the ethical debate. The aim is to advance readers' understanding and give guidance to those who have considered working with or incorporating the nudge approach into programs or policies aimed at making healthful choices easier.

  16. Shared decision making, paternalism and patient choice.

    Sandman, Lars; Munthe, Christian

    2010-03-01

    In patient centred care, shared decision making is a central feature and widely referred to as a norm for patient centred medical consultation. However, it is far from clear how to distinguish SDM from standard models and ideals for medical decision making, such as paternalism and patient choice, and e.g., whether paternalism and patient choice can involve a greater degree of the sort of sharing involved in SDM and still retain their essential features. In the article, different versions of SDM are explored, versions compatible with paternalism and patient choice as well as versions that go beyond these traditional decision making models. Whenever SDM is discussed or introduced it is of importance to be clear over which of these different versions are being pursued, since they connect to basic values and ideals of health care in different ways. It is further argued that we have reason to pursue versions of SDM involving, what is called, a high level dynamics in medical decision-making. This leaves four alternative models to choose between depending on how we balance between the values of patient best interest, patient autonomy, and an effective decision in terms of patient compliance or adherence: Shared Rational Deliberative Patient Choice, Shared Rational Deliberative Paternalism, Shared Rational Deliberative Joint Decision, and Professionally Driven Best Interest Compromise. In relation to these models it is argued that we ideally should use the Shared Rational Deliberative Joint Decision model. However, when the patient and professional fail to reach consensus we will have reason to pursue the Professionally Driven Best Interest Compromise model since this will best harmonise between the different values at stake: patient best interest, patient autonomy, patient adherence and a continued care relationship.

  17. Making Choices: Valletta, Development, Archaeology and Society

    Barney Sloane

    2018-03-01

    Full Text Available The European Archaeological Council's working group on 'Making Choices' conducted a survey of EAC member states about the ways in which they make decisions in archaeological heritage management with particular reference to development-led archaeological investigation. The driver for this is the belief that the approaches to development-led archaeology need to be more transparent and proportional to ensure continued state and developer/investor support. Based on a significant response (73% the survey gave a very useful insight into the way in which archaeological sites are defined and inventorised, the processes by which development-led investigations are designed, the means by which information is published and results (and collections archived, and the means by which the public are engaged in the process. The survey identified three key areas where choice-making is very much in the hands of the professional practice. These are: developing a clearer understanding of the significance of protected archaeological sites in the context of Valletta, assessing sensitivity to change for any sites proposed for development, and the design of the investigation itself. In addition, the survey revealed a clear interest in developing better ways of advocating the public value of development-led archaeology. This article summarises the issues raised in the survey and concludes that the most useful ways in which EAC could help its members would be through the preparation of guidance, case studies or toolkits — regardless of what legal or statutory structures are in operation in a given state — on the following subjects: understanding and articulating significance, developing national and regional research frameworks into which new excavations might be integrated, articulating the public value of archaeological investigation and developing better approaches to archaeological archives.

  18. Making Antibiotic Choices: Formula Derivation and Usage in the ...

    formulae was demonstrated in the rational selection of antibiotics most appropriate in the empirical ... antibiotics provides a suitable means of making antibiotic choices in the empirical treatment of ... decisions are made on their choices.

  19. Making the Most of Multiple Choice

    Brookhart, Susan M.

    2015-01-01

    Multiple-choice questions draw criticism because many people perceive they test only recall or atomistic, surface-level objectives and do not require students to think. Although this can be the case, it does not have to be that way. Susan M. Brookhart suggests that multiple-choice questions are a useful part of any teacher's questioning repertoire…

  20. Choice blindness in financial decision making

    Owen McLaughlin

    2013-09-01

    Full Text Available Choice Blindness is an experimental paradigm that examines the interplay between individuals' preferences, decisions, and expectations by manipulating the relationship between intention and choice. This paper expands upon the existing Choice Blindness framework by investigating the presence of the effect in an economically significant decision context, specifically that of pension choice. In addition, it investigates a number of secondary factors hypothesized to modulate Choice Blindness, including reaction time, risk preference, and decision complexity, as well as analysing the verbal reports of non-detecting participants. The experiment was administered to 100 participants of mixed age and educational attainment. The principal finding was that no more than 37.2% of manipulated trials were detected over all conditions, a result consistent with previous Choice Blindness research. Analysis of secondary factors found that reaction time, financial sophistication and decision complexity were significant predictors of Choice Blindness detection, while content analysis of non-detecting participant responses found that 20% implied significant preference changes and 62% adhered to initial preferences. Implications of the Choice Blindness effect in the context of behavioural economics are discussed, and an agenda for further investigation of the paradigm in this context is outlined.

  1. Making Healthy Choices at Fast Food Restaurants

    ... Conditions Prevention and Wellness Staying Healthy Healthy Living Travel Occupational Health First Aid and Injury Prevention Crisis Situations Pets and Animals myhealthfinder Food and Nutrition Healthy Food Choices Weight Loss and ...

  2. Desktop Publishing Choices: Making an Appropriate Decision.

    Crawford, Walt

    1991-01-01

    Discusses various choices available for desktop publishing systems. Four categories of software are described, including advanced word processing, graphics software, low-end desktop publishing, and mainstream desktop publishing; appropriate hardware is considered; and selection guidelines are offered, including current and future publishing needs,…

  3. Making personalised nutrition the easy choice

    Stewart-Knox, B.J.; Markovina, J.; Rankin, A.; Bunting, B.P.; Kuznesof, S.; Fischer, A.R.H.; Lans, van der I.A.; Poínhos, R.; Almeida, de M.D.V.; Panzone, L.; Gibney, M.; Frewer, L.J.

    2016-01-01

    Personalised diets based on people's existing food choices, and/or phenotypic, and/or genetic information hold potential to improve public dietary-related health. The aim of this analysis, therefore, has been to examine the degree to which factors which determine uptake of personalised nutrition

  4. Braving difficult choices alone: children's and adolescents' medical decision making.

    Azzurra Ruggeri

    Full Text Available OBJECTIVE: What role should minors play in making medical decisions? The authors examined children's and adolescents' desire to be involved in serious medical decisions and the emotional consequences associated with them. METHODS: Sixty-three children and 76 adolescents were presented with a cover story about a difficult medical choice. Participants were tested in one of four conditions: (1 own informed choice; (2 informed parents' choice to amputate; (3 informed parents' choice to continue a treatment; and (4 uninformed parents' choice to amputate. In a questionnaire, participants were asked about their choices, preference for autonomy, confidence, and emotional reactions when faced with a difficult hypothetical medical choice. RESULTS: Children and adolescents made different choices and participants, especially adolescents, preferred to make the difficult choice themselves, rather than having a parent make it. Children expressed fewer negative emotions than adolescents. Providing information about the alternatives did not affect participants' responses. CONCLUSIONS: Minors, especially adolescents, want to be responsible for their own medical decisions, even when the choice is a difficult one. For the adolescents, results suggest that the decision to be made, instead of the agent making the decision, is the main element influencing their emotional responses and decision confidence. For children, results suggest that they might be less able than adolescents to project how they would feel. The results, overall, draw attention to the need to further investigate how we can better involve minors in the medical decision-making process.

  5. Braving difficult choices alone: children's and adolescents' medical decision making.

    Ruggeri, Azzurra; Gummerum, Michaela; Hanoch, Yaniv

    2014-01-01

    What role should minors play in making medical decisions? The authors examined children's and adolescents' desire to be involved in serious medical decisions and the emotional consequences associated with them. Sixty-three children and 76 adolescents were presented with a cover story about a difficult medical choice. Participants were tested in one of four conditions: (1) own informed choice; (2) informed parents' choice to amputate; (3) informed parents' choice to continue a treatment; and (4) uninformed parents' choice to amputate. In a questionnaire, participants were asked about their choices, preference for autonomy, confidence, and emotional reactions when faced with a difficult hypothetical medical choice. Children and adolescents made different choices and participants, especially adolescents, preferred to make the difficult choice themselves, rather than having a parent make it. Children expressed fewer negative emotions than adolescents. Providing information about the alternatives did not affect participants' responses. Minors, especially adolescents, want to be responsible for their own medical decisions, even when the choice is a difficult one. For the adolescents, results suggest that the decision to be made, instead of the agent making the decision, is the main element influencing their emotional responses and decision confidence. For children, results suggest that they might be less able than adolescents to project how they would feel. The results, overall, draw attention to the need to further investigate how we can better involve minors in the medical decision-making process.

  6. Braving Difficult Choices Alone: Children's and Adolescents' Medical Decision Making

    Ruggeri, Azzurra; Gummerum, Michaela; Hanoch, Yaniv

    2014-01-01

    Objective What role should minors play in making medical decisions? The authors examined children's and adolescents' desire to be involved in serious medical decisions and the emotional consequences associated with them. Methods Sixty-three children and 76 adolescents were presented with a cover story about a difficult medical choice. Participants were tested in one of four conditions: (1) own informed choice; (2) informed parents' choice to amputate; (3) informed parents' choice to continue a treatment; and (4) uninformed parents' choice to amputate. In a questionnaire, participants were asked about their choices, preference for autonomy, confidence, and emotional reactions when faced with a difficult hypothetical medical choice. Results Children and adolescents made different choices and participants, especially adolescents, preferred to make the difficult choice themselves, rather than having a parent make it. Children expressed fewer negative emotions than adolescents. Providing information about the alternatives did not affect participants' responses. Conclusions Minors, especially adolescents, want to be responsible for their own medical decisions, even when the choice is a difficult one. For the adolescents, results suggest that the decision to be made, instead of the agent making the decision, is the main element influencing their emotional responses and decision confidence. For children, results suggest that they might be less able than adolescents to project how they would feel. The results, overall, draw attention to the need to further investigate how we can better involve minors in the medical decision-making process. PMID:25084274

  7. Assessing choice making among children with multiple disabilities.

    Sigafoos, J; Dempsey, R

    1992-01-01

    Some learners with multiple disabilities display idiosyncratic gestures that are interpreted as a means of making choices. In the present study, we assessed the validity of idiosyncratic choice-making behaviors of 3 children with multiple disabilities. Opportunities for each child to choose between food and drink were provided under two conditions. In one condition, the children were given the food or drink item corresponding to their prior choice. In the other condition, the teacher delivere...

  8. Affective biasing of choices in gambling task decision making.

    Hinson, John M; Whitney, Paul; Holben, Heather; Wirick, Aaron K

    2006-09-01

    The proponents of the somatic marker hypothesis presume that rational decision making is guided by emotional reactions that are developed from prior experience. Supporting evidence for the hypothesis comes almost exclusively from the short-term affective reactions that are learned during the course of a hypothetical decision-making task--the gambling task (GT). We examined GT performance and affective reactions to choices when those choices were biased by words that had preexisting affective value. In one experiment, affectively valued words directly signaled good and bad choices. A congruent relation between affective value of word and choice outcome improved GT performance, whereas an incongruent relation greatly interfered with performance. In another experiment, affectively valued words were maintained as a working memory (WM) load between GT choices. A WM load with affectively positive words somewhat improved GT performance, whereas affectively negative words interfered with performance. Somatic markers-indicated by differential anticipatory skin conductance response (SCR) amplitude for good and bad choices-appeared at a point in the GT session when choice performance was superior. However, differential SCR developed during the session after good choice performance was already established. These results indicate that preexisting affective biases can influence GT decision making. In addition, the somatic markers that are regular accompaniments of GT decision making appeared to be temporally lagging indicators of choice performance.

  9. Patients who make terrible therapeutic choices.

    Curzer, Howard J

    2014-01-01

    The traditional approaches to dental ethics include appeals to principles, duties (deontology), and consequences (utilitarianism). These approaches are often inadequate when faced with the case of a patient who refuses reasonable treatment and does not share the same ethical framework the dentist is using. An approach based on virtue ethics may be helpful in this and other cases. Virtue ethics is a tradition going back to Plato and Aristotle. It depends on forming a holistic character supporting general appropriate behavior. By correctly diagnosing the real issues at stake in a patient's inappropriate oral health choices and working to build effective habits, dentists can sometimes respond to ethical challenges that remain intractable given rule-based methods.

  10. Existential autonomy: why patients should make their own choices.

    Madder, H

    1997-08-01

    Savulescu has recently introduced the "rational non-interventional paternalist" model of the patient-doctor relationship. This paper addresses objections to such a model from the perspective of an anaesthetist. Patients need to make their own decisions if they are to be fully autonomous. Rational non-interventional paternalism undermines the importance of patient choice and so threatens autonomy. Doctors should provide an evaluative judgment of the best medical course of action, but ought to restrict themselves to helping patients to make their own choices rather than making such choices for them.

  11. Government Certification and Accreditation: Make a Choice

    Miles, Tracy L.

    2009-01-01

    One of the most significant challenges faced by government officials today is securing information systems to make them more resilient to attack from increasingly complex challenges from cyber-criminals, state-sponsored groups, and other threats. Over the years, the federal government has developed and implemented Certification and Accreditation…

  12. Rhetorical Design Studies: The Art of Making Design Choices Explicit

    Halstrøm, Per L.

    2017-01-01

    Design has the potential to affect the situations we are in, the choices we make and the beliefs we live by. Being such an affective field, one might expect that canonized design thinking models and methods would be much concerned with how designers can discover arguments for their design choices...

  13. Make Better Beverage Choices: 10 Tips to Get Started

    United States Department of Agriculture 10 tips Nutrition Education Series MyPlate MyWins Based on the Dietary Guidelines for Americans Make better beverage choices A healthy eating style includes all foods and beverages. Many beverages ...

  14. Choice-making treatment of young children's severe behavior problems.

    Peck, S M; Wacker, D P; Berg, W K; Cooper, L J; Brown, K A; Richman, D; McComas, J J; Frischmeyer, P; Millard, T

    1996-01-01

    The choice-making behavior of 5 young children with developmental disabilities who engaged in aberrant behavior was studied within a concurrent operants framework. Experimental analyses were conducted to identify reinforcers that maintained aberrant behavior, and functional communication training packages were implemented to teach the participants to gain reinforcement using mands. Next, a choice-making analysis, in which the participants chose one of two responses (either a mand or an altern...

  15. Food choice decision-making by women with gestational diabetes.

    Hui, Amy Leung; Sevenhuysen, Gustaaf; Harvey, Dexter; Salamon, Elizabeth

    2014-02-01

    To enhance the dietary education presented to women with gestational diabetes (GDM) by exploring the reasons and experiences that women with GDM reported in making their food-choice decisions after receipt of dietary education from a healthcare professional. Food Choice Map (FCM) semi-structured in-depth interviews were conducted with 30 women with GDM living in the Winnipeg area during their pregnancies. Verbatim transcripts were generated from the interviews. A constant comparative method was used to generate common themes to answer research inquiries. Personal food preferences, hunger and cravings were the main factors affecting food choice decision-making in women with GDM. Although the information from healthcare professionals was 1 factor that affected food choice decision-making for most of the participants, more than half of the women, including all the women who were on insulin, reported difficulties in quick adaptation to dietary management in a limited time period. Information from other sources such as family members, friends, and internet were used to cope with the adaptation. These difficulties led to a sense of decreased control of GDM and were accompanied by frustration, especially for women taking insulin. Food choice decision-making varied for this group of women with GDM. Knowledge and information aided in making healthy food choices and in portion control. However, balancing individual needs and blood glucose control in a short time period was felt to be difficult and created frustration. The findings suggested that dietary consultation needs to be personalized and to be time sensitive to promote confidence in self-control. Copyright © 2014 Canadian Diabetes Association. Published by Elsevier Inc. All rights reserved.

  16. Models of Affective Decision Making: How Do Feelings Predict Choice?

    Charpentier, Caroline J; De Neve, Jan-Emmanuel; Li, Xinyi; Roiser, Jonathan P; Sharot, Tali

    2016-06-01

    Intuitively, how you feel about potential outcomes will determine your decisions. Indeed, an implicit assumption in one of the most influential theories in psychology, prospect theory, is that feelings govern choice. Surprisingly, however, very little is known about the rules by which feelings are transformed into decisions. Here, we specified a computational model that used feelings to predict choices. We found that this model predicted choice better than existing value-based models, showing a unique contribution of feelings to decisions, over and above value. Similar to the value function in prospect theory, our feeling function showed diminished sensitivity to outcomes as value increased. However, loss aversion in choice was explained by an asymmetry in how feelings about losses and gains were weighted when making a decision, not by an asymmetry in the feelings themselves. The results provide new insights into how feelings are utilized to reach a decision. © The Author(s) 2016.

  17. Decision-making experiments and real-world choice behaviour

    Timmermans, H.J.P.; vd Heijden, R.E.C.M.; Westerveld, J.

    1984-01-01

    This article is concerned with the analysis of consumer spatial choice behaviour using conjoint measurements. The study's objectives are to assess the appropriateness of conjoint measurement to represent a consumer's spatial decision making process, to identify the nature of aggregate utility

  18. Making Choices about Hydrogen : Transport Issues for Developing ...

    30 sept. 2008 ... Couverture du livre Making Choices about Hydrogen : Transport Issues for Developing Countries ... International Water Resources Association, in close collaboration with IDRC, is holding a webinar titled “Climate change and adaptive water management: Innovative solutions from the Global South”.

  19. Complex Strategic Choices Applying Systemic Planning for Strategic Decision Making

    Leleur, Steen

    2012-01-01

    Effective decision making requires a clear methodology, particularly in a complex world of globalisation. Institutions and companies in all disciplines and sectors are faced with increasingly multi-faceted areas of uncertainty which cannot always be effectively handled by traditional strategies. Complex Strategic Choices provides clear principles and methods which can guide and support strategic decision making to face the many current challenges. By considering ways in which planning practices can be renewed and exploring the possibilities for acquiring awareness and tools to add value to strategic decision making, Complex Strategic Choices presents a methodology which is further illustrated by a number of case studies and example applications. Dr. Techn. Steen Leleur has adapted previously established research based on feedback and input from various conferences, journals and students resulting in new material stemming from and focusing on practical application of a systemic approach. The outcome is a coher...

  20. Melioration as rational choice: sequential decision making in uncertain environments.

    Sims, Chris R; Neth, Hansjörg; Jacobs, Robert A; Gray, Wayne D

    2013-01-01

    Melioration-defined as choosing a lesser, local gain over a greater longer term gain-is a behavioral tendency that people and pigeons share. As such, the empirical occurrence of meliorating behavior has frequently been interpreted as evidence that the mechanisms of human choice violate the norms of economic rationality. In some environments, the relationship between actions and outcomes is known. In this case, the rationality of choice behavior can be evaluated in terms of how successfully it maximizes utility given knowledge of the environmental contingencies. In most complex environments, however, the relationship between actions and future outcomes is uncertain and must be learned from experience. When the difficulty of this learning challenge is taken into account, it is not evident that melioration represents suboptimal choice behavior. In the present article, we examine human performance in a sequential decision-making experiment that is known to induce meliorating behavior. In keeping with previous results using this paradigm, we find that the majority of participants in the experiment fail to adopt the optimal decision strategy and instead demonstrate a significant bias toward melioration. To explore the origins of this behavior, we develop a rational analysis (Anderson, 1990) of the learning problem facing individuals in uncertain decision environments. Our analysis demonstrates that an unbiased learner would adopt melioration as the optimal response strategy for maximizing long-term gain. We suggest that many documented cases of melioration can be reinterpreted not as irrational choice but rather as globally optimal choice under uncertainty.

  1. Existential autonomy: why patients should make their own choices.

    Madder, H

    1997-01-01

    Savulescu has recently introduced the "rational non-interventional paternalist" model of the patient-doctor relationship. This paper addresses objections to such a model from the perspective of an anaesthetist. Patients need to make their own decisions if they are to be fully autonomous. Rational non-interventional paternalism undermines the importance of patient choice and so threatens autonomy. Doctors should provide an evaluative judgment of the best medical course of action, but ought to ...

  2. Simple model for multiple-choice collective decision making.

    Lee, Ching Hua; Lucas, Andrew

    2014-11-01

    We describe a simple model of heterogeneous, interacting agents making decisions between n≥2 discrete choices. For a special class of interactions, our model is the mean field description of random field Potts-like models and is effectively solved by finding the extrema of the average energy E per agent. In these cases, by studying the propagation of decision changes via avalanches, we argue that macroscopic dynamics is well captured by a gradient flow along E. We focus on the permutation symmetric case, where all n choices are (on average) the same, and spontaneous symmetry breaking (SSB) arises purely from cooperative social interactions. As examples, we show that bimodal heterogeneity naturally provides a mechanism for the spontaneous formation of hierarchies between decisions and that SSB is a preferred instability to discontinuous phase transitions between two symmetric points. Beyond the mean field limit, exponentially many stable equilibria emerge when we place this model on a graph of finite mean degree. We conclude with speculation on decision making with persistent collective oscillations. Throughout the paper, we emphasize analogies between methods of solution to our model and common intuition from diverse areas of physics, including statistical physics and electromagnetism.

  3. Local Choices: Rationality and the Contextuality of Decision-Making

    Vlaev, Ivo

    2018-01-01

    Rational explanation is ubiquitous in psychology and social sciences, ranging from rational analysis, expectancy-value theories, ideal observer models, mental logic to probabilistic frameworks, rational choice theory, and informal “folk psychological” explanation. However, rational explanation appears to be challenged by apparently systematic irrationality observed in psychological experiments, especially in the field of judgement and decision-making (JDM). Here, it is proposed that the experimental results require not that rational explanation should be rejected, but that rational explanation is local, i.e., within a context. Thus, rational models need to be supplemented with a theory of contextual shifts. We review evidence in JDM that patterns of choices are often consistent within contexts, but unstable between contexts. We also demonstrate that for a limited, though reasonably broad, class of decision-making domains, recent theoretical models can be viewed as providing theories of contextual shifts. It is argued that one particular significant source of global inconsistency arises from a cognitive inability to represent absolute magnitudes, whether for perceptual variables, utilities, payoffs, or probabilities. This overall argument provides a fresh perspective on the scope and limits of human rationality. PMID:29301289

  4. Local Choices: Rationality and the Contextuality of Decision-Making.

    Vlaev, Ivo

    2018-01-02

    Rational explanation is ubiquitous in psychology and social sciences, ranging from rational analysis, expectancy-value theories, ideal observer models, mental logic to probabilistic frameworks, rational choice theory, and informal "folk psychological" explanation. However, rational explanation appears to be challenged by apparently systematic irrationality observed in psychological experiments, especially in the field of judgement and decision-making (JDM). Here, it is proposed that the experimental results require not that rational explanation should be rejected, but that rational explanation is local , i.e., within a context. Thus, rational models need to be supplemented with a theory of contextual shifts. We review evidence in JDM that patterns of choices are often consistent within contexts, but unstable between contexts. We also demonstrate that for a limited, though reasonably broad, class of decision-making domains, recent theoretical models can be viewed as providing theories of contextual shifts. It is argued that one particular significant source of global inconsistency arises from a cognitive inability to represent absolute magnitudes, whether for perceptual variables, utilities, payoffs, or probabilities. This overall argument provides a fresh perspective on the scope and limits of human rationality.

  5. 'My kidneys, my choice, decision aid': supporting shared decision making.

    Fortnum, Debbie; Smolonogov, Tatiana; Walker, Rachael; Kairaitis, Luke; Pugh, Debbie

    2015-06-01

    For patients with chronic kidney disease (CKD) who are progressing to end-stage kidney disease (ESKD) a decision of whether to undertake dialysis or conservative care is a critical component of the patient journey. Shared decision making for complex decisions such as this could be enhanced by a decision aid, a practice which is well utilised in other disciplines but limited for nephrology. A multidisciplinary team in Australia and New Zealand (ANZ) utilised current decision-making theory and best practice to develop the 'My Kidneys, My Choice', a decision aid for the treatment of kidney disease. A patient-centred, five-sectioned tool is now complete and freely available to all ANZ units to support the ESKD education and shared decision-making process. Distribution and education have occurred across ANZ and evaluation of the decision aid in practice is in the first phase. Development of a new tool such as an ESKD decision aid requires vision, multidisciplinary input and ongoing implementation resources. This tool is being integrated into ANZ, ESKD education practice and is promoting the philosophy of shared decision making. © 2014 European Dialysis and Transplant Nurses Association/European Renal Care Association.

  6. Understanding How Overweight and Obese Emerging Adults Make Lifestyle Choices.

    Cha, EunSeok; Crowe, James M; Braxter, Betty J; Jennings, Bonnie Mowinski

    To better understand health-related decision making among overweight and obese emerging adults. A cross-sectional design was used in the parent study involving overweight and obese emerging adults, ages 18-29 years. The goal of the parent study was to screen participants' diabetes risk and identify characteristics of emerging adults with prediabetes (N=107). A sub-sample of respondents (n=34) from the parent study were invited to participate in focus group interviews depending on whether they had prediabetes (three groups) or they did not have prediabetes (four groups). Each focus group interview lasted 90-120 minutes following a semi-structured interview guide. Conventional content analysis was used in the data analysis. Because of the similarities between participants with and without prediabetes, the findings were synthesized and reported in the aggregate. Moreover, during the analysis, the authors decided that rational choice theory provided a useful organizing structure for presenting the data. Emerging adults' behavioral decisions were rational reactions to their personal competence, perception of health, environment, and availability of resources to handle problems. Calculation of trade-offs and estimations of resource availability were often used when making decisions. Emerging adults choose unhealthy behaviors due to inaccurate information and insufficient competence to practice healthy lifestyles rather than because of laziness or being irrational. Behavioral interventions for emerging adults need to help them develop skills to enhance health literacy and problem solving, thereby enhancing their awareness of available resources and decreasing the perceived cost of making healthy choices. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Protect Your Heart: Check Food Labels to Make Heart-Healthy Choices

    ... Protein 15g Total Amounts To make heart-healthy food choices, look at the totals and cut back on • ... Toolkit No. 8: Protect Your Heart: Make Smart Food Choices • Toolkit No. 9: Protect Your Heart: Choose Fats ...

  8. The priority heuristic: making choices without trade-offs.

    Brandstätter, Eduard; Gigerenzer, Gerd; Hertwig, Ralph

    2006-04-01

    Bernoulli's framework of expected utility serves as a model for various psychological processes, including motivation, moral sense, attitudes, and decision making. To account for evidence at variance with expected utility, the authors generalize the framework of fast and frugal heuristics from inferences to preferences. The priority heuristic predicts (a) the Allais paradox, (b) risk aversion for gains if probabilities are high, (c) risk seeking for gains if probabilities are low (e.g., lottery tickets), (d) risk aversion for losses if probabilities are low (e.g., buying insurance), (e) risk seeking for losses if probabilities are high, (f) the certainty effect, (g) the possibility effect, and (h) intransitivities. The authors test how accurately the heuristic predicts people's choices, compared with previously proposed heuristics and 3 modifications of expected utility theory: security-potential/aspiration theory, transfer-of-attention-exchange model, and cumulative prospect theory. ((c) 2006 APA, all rights reserved).

  9. The Priority Heuristic: Making Choices Without Trade-Offs

    Brandstätter, Eduard; Gigerenzer, Gerd; Hertwig, Ralph

    2010-01-01

    Bernoulli's framework of expected utility serves as a model for various psychological processes, including motivation, moral sense, attitudes, and decision making. To account for evidence at variance with expected utility, we generalize the framework of fast and frugal heuristics from inferences to preferences. The priority heuristic predicts (i) Allais' paradox, (ii) risk aversion for gains if probabilities are high, (iii) risk seeking for gains if probabilities are low (lottery tickets), (iv) risk aversion for losses if probabilities are low (buying insurance), (v) risk seeking for losses if probabilities are high, (vi) certainty effect, (vii) possibility effect, and (viii) intransitivities. We test how accurately the heuristic predicts people's choices, compared to previously proposed heuristics and three modifications of expected utility theory: security-potential/aspiration theory, transfer-of-attention-exchange model, and cumulative prospect theory. PMID:16637767

  10. Nudge or Grudge? Choice Architecture and Parental Decision-Making.

    Blumenthal-Barby, Jennifer; Opel, Douglas J

    2018-03-01

    Richard Thaler and Cass Sunstein define a nudge as "any aspect of the choice architecture that alters people's behavior in a predictable way without forbidding any options or significantly changing their economic incentives." Much has been written about the ethics of nudging competent adult patients. Less has been written about the ethics of nudging surrogates' decision-making and how the ethical considerations and arguments in that context might differ. Even less has been written about nudging surrogate decision-making in the context of pediatrics, despite fundamental differences that exist between the pediatric and adult contexts. Yet, as the field of behavioral economics matures and its insights become more established and well-known, nudges will become more crafted, sophisticated, intentional, and targeted. Thus, the time is now for reflection and ethical analysis regarding the appropriateness of nudges in pediatrics. We argue that there is an even stronger ethical justification for nudging in parental decision-making than with competent adult patients deciding for themselves. We give three main reasons in support of this: (1) child patients do not have autonomy that can be violated (a concern with some nudges), and nudging need not violate parental decision-making authority; (2) nudging can help fulfill pediatric clinicians' obligations to ensure parental decisions are in the child's interests, particularly in contexts where there is high certainty that a recommended intervention is low risk and of high benefit; and (3) nudging can relieve parents' decisional burden regarding what is best for their child, particularly with decisions that have implications for public health. © 2018 The Hastings Center.

  11. The anatomy of choice: dopamine and decision-making.

    Friston, Karl; Schwartenbeck, Philipp; FitzGerald, Thomas; Moutoussis, Michael; Behrens, Timothy; Dolan, Raymond J

    2014-11-05

    This paper considers goal-directed decision-making in terms of embodied or active inference. We associate bounded rationality with approximate Bayesian inference that optimizes a free energy bound on model evidence. Several constructs such as expected utility, exploration or novelty bonuses, softmax choice rules and optimism bias emerge as natural consequences of free energy minimization. Previous accounts of active inference have focused on predictive coding. In this paper, we consider variational Bayes as a scheme that the brain might use for approximate Bayesian inference. This scheme provides formal constraints on the computational anatomy of inference and action, which appear to be remarkably consistent with neuroanatomy. Active inference contextualizes optimal decision theory within embodied inference, where goals become prior beliefs. For example, expected utility theory emerges as a special case of free energy minimization, where the sensitivity or inverse temperature (associated with softmax functions and quantal response equilibria) has a unique and Bayes-optimal solution. Crucially, this sensitivity corresponds to the precision of beliefs about behaviour. The changes in precision during variational updates are remarkably reminiscent of empirical dopaminergic responses-and they may provide a new perspective on the role of dopamine in assimilating reward prediction errors to optimize decision-making.

  12. How Politicians Make Decisions: A Political Choice Experiment

    Fatás, Enrique; Neugebauer, Tibor; Tamborero, Pilar

    2004-01-01

    The present paper reports on a political choice experiment with elected real-world politicians. A questionnaire on political and public issues is taken to examine whether prospect theory predicts the responses of experts from the field better than rational choice theory. The results indicate that framing effects exist but that expertise may weaken the deviation from rational choice.

  13. Make the healthy choice the easy choice: using behavioral economics to advance a culture of health.

    Volpp, K G; Asch, D A

    2017-05-01

    Despite great advances in the science and technology of health care, a large gap separates theoretically achievable advances in health from what individuals and populations actually achieve. Human behavior sits on the final common pathway to so many of our health and health care goals, including the prevention and management of illness and the fostering of wellness. Behavioral economics is a relatively new field offering approaches to supplement many of the conventional approaches to improving health behaviors that rely on education or standard economic theory. While those conventional approaches presume that an educated public will naturally make decisions that optimize personal welfare, approaches derived from behavioral economics harness existing and predictable patterns of behavior that often lead people to make choices against their best interests. By keeping these predictable patterns of behavior in mind when designing health insurance, health care programs or the health-related aspects of everyday life, behavioral economists aim to meet people half-way: no longer asking them to reshape their behavior to something more health promoting, but helping the behavioral patterns they already follow lead them to better health. © The Author 2016. Published by Oxford University Press on behalf of the Association of Physicians. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  14. How politicians make decisions under risk: a political choice experiment

    Enrique Fatás; Tibor Neugebauer; Pilar Tamborero

    2004-01-01

    We report on an experimental study with real-world politicians. These political experts face political choice problems under risk and probability. Thus, we test the frequently observed violations of rational choice theory -the reference point effect, loss aversion, framing effects, and the common ratio effect- with experts from the field. Their choices violate expected utility theory. Nevertheless, they appear to be more rational and less risk averse (loving) in the domain of gains (losses) t...

  15. The dynamics of user perception, decision making and route choice

    Vreeswijk, Jacob Dirk

    2015-01-01

    Travellers’ response to performance changes in the traffic system is a decisive factor in the effectiveness of traffic management measures. This thesis provides an empirical and quantitative assessment of choice behaviour and the effects of perception error on choice outcomes. It considers users’

  16. Selective attention increases choice certainty in human decision making.

    Zizlsperger, Leopold; Sauvigny, Thomas; Haarmeier, Thomas

    2012-01-01

    Choice certainty is a probabilistic estimate of past performance and expected outcome. In perceptual decisions the degree of confidence correlates closely with choice accuracy and reaction times, suggesting an intimate relationship to objective performance. Here we show that spatial and feature-based attention increase human subjects' certainty more than accuracy in visual motion discrimination tasks. Our findings demonstrate for the first time a dissociation of choice accuracy and certainty with a significantly stronger influence of voluntary top-down attention on subjective performance measures than on objective performance. These results reveal a so far unknown mechanism of the selection process implemented by attention and suggest a unique biological valence of choice certainty beyond a faithful reflection of the decision process.

  17. The Impact of Irish Policy and Legislation on How Adults with Learning Disabilities Make Choices

    Carey, Eileen; Griffiths, Colin

    2016-01-01

    This paper reflects the impact of policy and legislation in the context of how adults with learning disabilities make choices. Following an overview of policies which have improved choice for people with learning disability in the United Kingdom, this paper reviews "choice" in current Irish policy and legislation. This paper, while…

  18. Melioration as Rational Choice: Sequential Decision Making in Uncertain Environments

    Sims, Chris R.; Neth, Hansjorg; Jacobs, Robert A.; Gray, Wayne D.

    2013-01-01

    Melioration--defined as choosing a lesser, local gain over a greater longer term gain--is a behavioral tendency that people and pigeons share. As such, the empirical occurrence of meliorating behavior has frequently been interpreted as evidence that the mechanisms of human choice violate the norms of economic rationality. In some environments, the…

  19. Shape Your Family's Habits: Helping Kids Make Healthy Choices

    ... kids to be active. When it comes to food and physical activity, what you say and do around your children can have a lasting effect. Work ... Choices Help Kids Form Healthy Habits Be a role model. Eat healthy family meals together. Walk or ride ...

  20. Behavioral Economics and the Supplemental Nutrition Assistance Program:: Making the Healthy Choice the Easy Choice.

    Ammerman, Alice S; Hartman, Terry; DeMarco, Molly M

    2017-02-01

    The Supplemental Nutrition Assistance Program (SNAP) serves as an important nutritional safety net program for many Americans. Given its aim to use traditional economic levers to provide access to food, the SNAP program includes minimal nutritional requirements and restrictions. As food choices are influenced by more than just economic constraints, behavioral economics may offer insights and tools for altering food purchases for SNAP users. This manuscript outlines behavioral economics strategies that have potential to encourage healthier food choices within the SNAP program. Copyright © 2016 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

  1. Making Choices: Self-Directed Teams or Total Quality Management?

    Holpp, Lawrence

    1992-01-01

    Describes differences between total quality management and self-directed teams in terms of job design, decision making, flexibility, supervision, labor relations, quality, customers, and training. Offers suggestions for which method to choose when. (SK)

  2. Why did Jacques Monod make the choice of mechanistic determinism?

    Loison, Laurent

    2015-06-01

    The development of molecular biology placed in the foreground a mechanistic and deterministic conception of the functioning of macromolecules. In this article, I show that this conception was neither obvious, nor necessary. Taking Jacques Monod as a case study, I detail the way he gradually came loose from a statistical understanding of determinism to finally support a mechanistic understanding. The reasons of the choice made by Monod at the beginning of the 1950s can be understood only in the light of the general theoretical schema supported by the concept of mechanistic determinism. This schema articulates three fundamental notions for Monod, namely that of the rigidity of the sequence of the genetic program, that of the intrinsic stability of macromolecules (DNA and proteins), and that of the specificity of molecular interactions. Copyright © 2015 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  3. Cr-W-V bainitic/ferritic steel with improved strength and toughness and method of making

    Klueh, R.L.; Maziasz, P.J.

    1994-03-08

    This work describes a high strength, high toughness bainitic/ferritic steel alloy comprising about 2.75% to 4.0% chromium, about 2.0% to 3.5% tungsten, about 0.10% to 0.30% vanadium, and about 0.1% to 0.15% carbon with the balance iron, wherein the percentages are by total weight of the composition, wherein the alloy having been heated to an austenitizing temperature and then cooled at a rate sufficient to produce carbide-free acicular bainite. 15 figures.

  4. Bayesian probability estimates are not necessary to make choices satisfying Bayes’ rule in elementary situations

    Artur eDomurat

    2015-08-01

    Full Text Available This paper has two aims. First, we investigate how often people make choices conforming to Bayes’ rule when natural sampling is applied. Second, we show that using Bayes’ rule is not necessary to make choices satisfying Bayes’ rule. Simpler methods, even fallacious heuristics, might prescribe correct choices reasonably often under specific circumstances. We considered elementary situations with binary sets of hypotheses and data. We adopted an ecological approach and prepared two-stage computer tasks resembling natural sampling. Probabilistic relations were to be inferred from a set of pictures, followed by a choice between the data which was made to maximize a chance for a preferred outcome. Using Bayes’ rule was deduced indirectly from choices.Study 1 (N=60 followed a 2 (gender: female vs. male x 2 (education: humanities vs. pure sciences between-subjects factorial design with balanced cells, and a number of correct choices as a dependent variable. Choices satisfying Bayes’ rule were dominant. To investigate ways of making choices more directly, we replicated Study 1, adding a task with a verbal report. In Study 2 (N=76 choices conforming to Bayes’ rule dominated again. However, the verbal reports revealed use of a new, non-inverse rule, which always renders correct choices, but is easier than Bayes’ rule to apply. It does not require inversing conditions (transforming P(H and P(D|H into P(H|D when computing chances. Study 3 examined efficiency of the three fallacious heuristics (pre-Bayesian, representativeness, and evidence-only in producing choices concordant with Bayes’ rule. Computer-simulated scenarios revealed that the heuristics produce correct choices reasonably often under specific base rates and likelihood ratios. Summing up we conclude that natural sampling leads to most choices conforming to Bayes’ rule. However, people tend to replace Bayes’ rule with simpler methods, and even use of fallacious heuristics may

  5. Separate neural mechanisms underlie choices and strategic preferences in risky decision making.

    Venkatraman, Vinod; Payne, John W; Bettman, James R; Luce, Mary Frances; Huettel, Scott A

    2009-05-28

    Adaptive decision making in real-world contexts often relies on strategic simplifications of decision problems. Yet, the neural mechanisms that shape these strategies and their implementation remain largely unknown. Using an economic decision-making task, we dissociate brain regions that predict specific choices from those predicting an individual's preferred strategy. Choices that maximized gains or minimized losses were predicted by functional magnetic resonance imaging activation in ventromedial prefrontal cortex or anterior insula, respectively. However, choices that followed a simplifying strategy (i.e., attending to overall probability of winning) were associated with activation in parietal and lateral prefrontal cortices. Dorsomedial prefrontal cortex, through differential functional connectivity with parietal and insular cortex, predicted individual variability in strategic preferences. Finally, we demonstrate that robust decision strategies follow from neural sensitivity to rewards. We conclude that decision making reflects more than compensatory interaction of choice-related regions; in addition, specific brain systems potentiate choices depending on strategies, traits, and context.

  6. Making Good Choices: Districts Take the Lead. Comprehensive School Reform.

    North Central Regional Educational Lab., Oak Brook, IL.

    Public schools across the country are aiming to improve student performance by engaging in comprehensive school reform (CSR). This guide was created to help school districts make CSR an integral part of their strategies for improving student achievement. Five components for CSR are described: (1) Strategizing, whereby the district supports CSR by…

  7. Hungry pigeons make suboptimal choices, less hungry pigeons do not.

    Laude, Jennifer R; Pattison, Kristina F; Zentall, Thomas R

    2012-10-01

    Hungry animals will often choose suboptimally by being attracted to reliable signals for food that occur infrequently (they gamble) over less reliable signals for food that occur more often. That is, pigeons prefer an option that 50 % of the time provides them with a reliable signal for the appearance of food but 50 % of the time provides them with a reliable signal for the absence of food (overall 50 % reinforcement) over an alternative that always provides them with a signal for the appearance of food 75 % of the time (overall 75 % reinforcement). The pigeons appear to choose impulsively for the possibility of obtaining the reliable signal for reinforcement. There is evidence that greater hunger is associated with greater impulsivity. We tested the hypothesis that if the pigeons were less hungry, they would be less impulsive and, thus, would choose more optimally (i.e., on the basis of the overall probability of reinforcement). We found that hungry pigeons choose the 50 % reinforcement alternative suboptimally but less hungry pigeons prefer the more optimal 75 % reinforcement. Paradoxically, pigeons that needed the food more received less of it. These findings have implications for how level of motivation may also affect human suboptimal choice (e.g., purchase of lottery tickets and playing slot machines).

  8. Adapting Scott and Bruce's General Decision-Making Style Inventory to Patient Decision Making in Provider Choice.

    Fischer, Sophia; Soyez, Katja; Gurtner, Sebastian

    2015-05-01

    Research testing the concept of decision-making styles in specific contexts such as health care-related choices is missing. Therefore, we examine the contextuality of Scott and Bruce's (1995) General Decision-Making Style Inventory with respect to patient choice situations. Scott and Bruce's scale was adapted for use as a patient decision-making style inventory. In total, 388 German patients who underwent elective joint surgery responded to a questionnaire about their provider choice. Confirmatory factor analyses within 2 independent samples assessed factorial structure, reliability, and validity of the scale. The final 4-dimensional, 13-item patient decision-making style inventory showed satisfactory psychometric properties. Data analyses supported reliability and construct validity. Besides the intuitive, dependent, and avoidant style, a new subdimension, called "comparative" decision-making style, emerged that originated from the rational dimension of the general model. This research provides evidence for the contextuality of decision-making style to specific choice situations. Using a limited set of indicators, this report proposes the patient decision-making style inventory as valid and feasible tool to assess patients' decision propensities. © The Author(s) 2015.

  9. A Decision Making Analysis of Persuasive Argumentation and the Choice Shift Effect

    Vinokur, Amiram; And Others

    1975-01-01

    A subjective expected utility (SEU) decision-making analysis was performed on the content of arguments generated by subjects privately or during group discussion in response to choice-dilemmas shown to shift toward risk and caution. (Editor)

  10. Bayesian probability estimates are not necessary to make choices satisfying Bayes’ rule in elementary situations

    Domurat, Artur; Kowalczuk, Olga; Idzikowska, Katarzyna; Borzymowska, Zuzanna; Nowak-Przygodzka, Marta

    2015-01-01

    This paper has two aims. First, we investigate how often people make choices conforming to Bayes’ rule when natural sampling is applied. Second, we show that using Bayes’ rule is not necessary to make choices satisfying Bayes’ rule. Simpler methods, even fallacious heuristics, might prescribe correct choices reasonably often under specific circumstances. We considered elementary situations with binary sets of hypotheses and data. We adopted an ecological approach and prepared two-stage computer tasks resembling natural sampling. Probabilistic relations were inferred from a set of pictures, followed by a choice which was made to maximize the chance of a preferred outcome. Use of Bayes’ rule was deduced indirectly from choices. Study 1 used a stratified sample of N = 60 participants equally distributed with regard to gender and type of education (humanities vs. pure sciences). Choices satisfying Bayes’ rule were dominant. To investigate ways of making choices more directly, we replicated Study 1, adding a task with a verbal report. In Study 2 (N = 76) choices conforming to Bayes’ rule dominated again. However, the verbal reports revealed use of a new, non-inverse rule, which always renders correct choices, but is easier than Bayes’ rule to apply. It does not require inversion of conditions [transforming P(H) and P(D|H) into P(H|D)] when computing chances. Study 3 examined the efficiency of three fallacious heuristics (pre-Bayesian, representativeness, and evidence-only) in producing choices concordant with Bayes’ rule. Computer-simulated scenarios revealed that the heuristics produced correct choices reasonably often under specific base rates and likelihood ratios. Summing up we conclude that natural sampling results in most choices conforming to Bayes’ rule. However, people tend to replace Bayes’ rule with simpler methods, and even use of fallacious heuristics may be satisfactorily efficient. PMID:26347676

  11. >From individual choice to group decision-making

    Galam, Serge; Zucker, Jean-Daniel

    2000-12-01

    Some universal features are independent of both the social nature of the individuals making the decision and the nature of the decision itself. On this basis a simple magnet like model is built. Pair interactions are introduced to measure the degree of exchange among individuals while discussing. An external uniform field is included to account for a possible pressure from outside. Individual biases with respect to the issue at stake are also included using local random fields. A unique postulate of minimum conflict is assumed. The model is then solved with emphasis on its psycho-sociological implications. Counter-intuitive results are obtained. At this stage no new physical technicality is involved. Instead the full psycho-sociological implications of the model are drawn. Few cases are then detailed to enlight them. In addition, several numerical experiments based on our model are shown to give both an insight on the dynamics of the model and suggest further research directions.

  12. Pharmacy career deciding: making choice a "good fit".

    Willis, Sarah Caroline; Shann, Phillip; Hassell, Karen

    2009-01-01

    The purpose of this article is to explore factors influencing career deciding amongst pharmacy students and graduates in the U.K. Group interviews were used to devise a topic guide for five subsequent focus groups with pharmacy students and graduates. Focus groups were tape-recorded, recordings transcribed, and transcripts analysed. Key themes and interlinking factors relating to pharmacy career deciding were identified in the transcripts, following a constructivist approach. Participants' described making a "good fit" between themselves, their experiences, social networks etc. and pharmacy. Central to a coherent career deciding narrative were: having a job on graduation; and the instrumental advantage of studying a vocational course. Focusing on career deciding of UK pharmacy students and graduates may limit the study's generalisability to other countries. However, our findings are relevant to those interested in understanding students' motivations for healthcare careers, since our results suggest that making a "good fit" describes a general process of matching between a healthcare career and personal experience. As we have found that pharmacy career deciding was not, usually, a planned activity, career advisors and those involved in higher education recruitment should take into account the roles played by personal preferences and values in choosing a degree course. A qualitative study like this can illustrate how career deciding occurs and provide insight into the process from a student's perspective. This can help inform guidance processes, selection to healthcare professions courses within the higher education sector, and stimulate debate amongst those involved with recruitment of healthcare workers about desirable motivators for healthcare careers.

  13. Dental patient preferences and choice in clinical decision-making.

    Fukai, Kakuhiro; Yoshino, Koichi; Ohyama, Atsushi; Takaesu, Yoshinori

    2012-01-01

    In economics, the concept of utility refers to the strength of customer preference. In health care assessment, the visual analogue scale (VAS), the standard gamble, and the time trade-off are used to measure health state utilities. These utility measurements play a key role in promoting shared decision-making in dental care. Individual preference, however, is complex and dynamic. The purpose of this study was to investigate the relationship between patient preference and educational intervention in the field of dental health. The data were collected by distributing questionnaires to employees of two companies in Japan. Participants were aged 18-65 years and consisted of 111 males and 93 females (204 in total). One company (Group A) had a dental program of annual check-ups and health education in the workplace, while the other company (Group B) had no such program. Statistical analyses were performed with the t-test and Chi-square test. The questionnaire items were designed to determine: (1) oral health-related quality of life, (2) dental health state utilities (using VAS), and (3) time trade-off for regular dental check-ups. The percentage of respondents in both groups who were satisfied with chewing function, appearance of teeth, and social function ranged from 23.1 to 42.4%. There were no significant differences between groups A and B in the VAS of decayed, filled, and missing teeth. The VAS of gum bleeding was 42.8 in Group A and 51.3 in Group B (pdecision-making.

  14. Persistent optimizing: how mothers make food choices for their preschool children.

    Walsh, Audrey; Meagher-Stewart, Donna; Macdonald, Marilyn

    2015-04-01

    Mothers' ability to provide healthy food choices for their children has become more complex in our current obesogenic environment. We conducted a total of 35 interviews with 18 mothers of preschool children. Using constructivist grounded theory methods, we developed a substantive theory of how mothers make food choices for their preschoolers. Our substantive theory, persistent optimizing, consists of three main integrated conceptual categories: (a) acknowledging contextual constraints, (b) stretching boundaries, and (c) strategic positioning. Implications to improve mothers' ability to make healthy food choices that reduce their children's risk of becoming overweight or obese are discussed. © The Author(s) 2014.

  15. One-reason decision making in risky choice? A closer look at the priority heuristic

    Benjamin E. Hilbig

    2008-08-01

    Full Text Available Although many models for risky choices between gambles assume that information is somehow integrated, the recently proposed priority heuristic (PH claims that choices are based on one piece of information only. That is, although the current reason for a choice according to the PH can vary, all other reasons are claimed to be ignored. However, the choices predicted by the PH and other pieces of information are often confounded, thus rendering critical tests of whether decisions are actually based on one reason only, impossible. The current study aims to remedy this problem by manipulating the number of reasons additionally in line with the choice implied by the PH. The results show that participants' choices and decision times depend heavily on the number of reasons in line with the PH --- thus contradicting the notion of non-compensatory, one-reason decision making.

  16. Parental Influence on Exploratory Students' College Choice, Major, and Career Decision Making

    Workman, Jamie L.

    2015-01-01

    This article explores parental influence on exploratory students' college choice, major, and career decision making. The research began with examination of a first year academic advising model and Living Learning Community. Parental influence emerged as a key theme in student decision making processes. The project was conducted using grounded…

  17. Tragic Choices in Humanitarian Aid : A Framework of Organizational Determinants of NGO Decision Making

    Heyse, Liesbet

    Humanitarian NGOs face difficult choices about whom to help and whom not on a daily basis. The research question in this article is how humanitarian NGOs make these difficult decisions and why in a particular way. March's study on consequential and appropriate decision-making processes is used to

  18. Free-Choice Learning Suited to Women's Participation Needs in Environmental Decision-Making Processes

    Skanavis, Constantina; Sakellari, Maria

    2012-01-01

    United Nations mandates recognize the need to promote the full participation of women in environmental decision-making processes on the basis of gender equality. But, there remains a profound lack of effective women's participation in some sectors of environmental decision-making. Free-choice environmental learning offers an effective educational…

  19. Preventing School Employee Sexual Misconduct: An Outcome Survey Analysis of Making Right Choices.

    Lipson, Glenn; Grant, Billie-Jo; Mueller, Jessica; Sonnich, Steve

    2018-05-30

    This treatment-only study examines the impact of Making Right Choices, an online course prevention program designed to promote the knowledge, awareness, and prevention of school employee sexual misconduct. The sample included 13,007 school employee participants who took the Making Right Choices course between May 6, 2011, and March 12, 2017, in California and New York. The 20-item measure, Preventing Misconduct Assessment, was administered to participants at the end of the online course; completion of the measure was voluntary. Descriptive statistics revealed that a large majority of participants reported increasing their knowledge and awareness of school employee sexual misconduct because of their participation in the Making Right Choices online course. This study yields important findings regarding the impact of a sexual misconduct prevention program and, specifically, the difference it may make for non-licensed school employees. These findings indicate that school employees are accepting of sexual misconduct training programs and rate them as having value.

  20. Making ethical choices: a comprehensive decision-making model for Canadian psychologists.

    Hadjistavropoulos, T; Malloy, D C

    2000-05-01

    This paper proposes a theoretical augmentation of the seven-step decision-making model outlined in the Canadian Code of Ethics for Psychologists. We propose that teleological, deontological, and existential ethical perspectives should be taken into account in the decision-making process. We also consider the influence of individual, issue-specific, significant-other, situational, and external factors on ethical decision-making. This theoretical analysis demonstrates the richness and complexity of ethical decision-making.

  1. The Making of Informed Choice in Midwifery: A Feminist Experiment in Care.

    MacDonald, Margaret E

    2017-11-15

    This paper is about the clinical principle of informed choice-the hallmark feature of the midwifery model of care in Ontario, Canada. Drawing on ethnographic history interviews with midwives, I trace the origins of the idea of informed choice to its roots in the social movement of midwifery in North America in the late 1960s and 1970s. At that time informed choice was not the distinctive feature of midwifery but was deeply embedded what I call midwifery's feminist experiment in care. But as midwifery in Ontario transitioned from a social movement to a full profession within the formal health care system, informed choice was strategically foregrounded in order to make the midwifery model of care legible and acceptable to a skeptical medical profession, conservative law makers, and a mainstream clientele. As mainstream biomedicine now takes up the rhetoric of patient empowerment and informed choice, this paper is at once a nuanced history of the making of the concept and also a critique of the ascendant 'regime of choice' in contemporary health care, inspired by the reflections of the midwives in my study for whom choice is impossible without care.

  2. RELATION BETWEEN QUALITY OF LIFE, CHOICE MAKING, AND FUTURE EXPECTATIONS IN ADULTS WITH INTELLECTUAL DISABILITY

    Vesna KOSTIKJ-IVANOVIKJ

    2016-09-01

    Full Text Available Introduction: Quality of life of individuals depends significantly on the ability to have control over everyday life, realized through the freedom to make choices from available options and self-determination. Objective: To determine the correlation between possibilities for making choices and expectations for the future with the quality of life in adults with intellectual disabilities according self-assessment and assessment by others. Methods: Descriptive, method of correlation and comparative analysis ware applied. From techniques, analysis of documents, surveys with the Quality of life questionnaire by Schalock and Keith and Questionnaire for expectations for the future by Speck, and scaling with the Scale for assessment of the opportunities for making choices by Kishi et al. Sample consisted of 130 intellectually disabled adults and 130 proxies. For establishing connection between the examined phenomena Pearson correlation coefficient (r was used, at p<0,01. Results: There is a strong correlation between the results obtained from the questionnaires about quality of life and opportunities for making choices, self-assessment r(130=0,497, p<0,01, assessment by others r(130=0,482, p<0,01. There is a correlation between the results obtained from the questionnaires about quality of life and expectations for the future, but not very strong, self-assessment r(130=0,233, p=0,008<0,01, assessment by others r(130=0,305, p<0,01. Conclusion: There is a correlation between opportunities for making choices and expectations for the future with the quality of life in adults with intellectual disabilities. To improve the quality of life in these individuals, it is necessary to design programs that will develop self-concept, abilities for self-determination and making personal choices.

  3. Do Moral Choices Make Us Feel Good? The Development of Adolescents' Emotions Following Moral Decision Making

    Malti, Tina; Keller, Monika; Buchmann, Marlis

    2013-01-01

    Some people believe that making the morally right decision makes people feel good. However, until now, there has been no empirical evidence in support of this belief. In a representative two-wave longitudinal study of 995 15-year-old adolescents followed for 3 years (until the age of 18) in Switzerland, adolescents were asked about their decisions…

  4. The Effects of Frequency of Media Utilization on Decision Making of Media Choice

    Gotoh, Yasushi

    2014-01-01

    The purpose of this study is to use the Analytic Hierarchy Process in order to identify how frequency of media use in daily life affects decision-making in media choice. 276 university students took part in this research, They were asked to prioritize their ways of obtaining information about current affairs using sets of media such as TV, books,…

  5. Prefrontal spatial working memory network predicts animal's decision making in a free choice saccade task.

    Mochizuki, Kei; Funahashi, Shintaro

    2016-01-01

    While neurons in the lateral prefrontal cortex (PFC) encode spatial information during the performance of working memory tasks, they are also known to participate in subjective behavior such as spatial attention and action selection. In the present study, we analyzed the activity of primate PFC neurons during the performance of a free choice memory-guided saccade task in which the monkeys needed to choose a saccade direction by themselves. In trials when the receptive field location was subsequently chosen by the animal, PFC neurons with spatially selective visual response started to show greater activation before cue onset. This result suggests that the fluctuation of firing before cue presentation prematurely biased the representation of a certain spatial location and eventually encouraged the subsequent choice of that location. In addition, modulation of the activity by the animal's choice was observed only in neurons with high sustainability of activation and was also dependent on the spatial configuration of the visual cues. These findings were consistent with known characteristics of PFC neurons in information maintenance in spatial working memory function. These results suggest that precue fluctuation of spatial representation was shared and enhanced through the working memory network in the PFC and could finally influence the animal's free choice of saccade direction. The present study revealed that the PFC plays an important role in decision making in a free choice condition and that the dynamics of decision making are constrained by the network architecture embedded in this cortical area. Copyright © 2016 the American Physiological Society.

  6. Beyond labelling: what strategies do nut allergic individuals employ to make food choices? A qualitative study.

    Julie Barnett

    Full Text Available OBJECTIVE: Food labelling is an important tool that assists people with peanut and tree nut allergies to avoid allergens. Nonetheless, other strategies are also developed and used in food choice decision making. In this paper, we examined the strategies that nut allergic individuals deploy to make safe food choices in addition to a reliance on food labelling. METHODS: THREE QUALITATIVE METHODS: an accompanied shop, in-depth semi-structured interviews, and the product choice reasoning task - were used with 32 patients that had a clinical history of reactions to peanuts and/or tree nuts consistent with IgE-mediated food allergy. Thematic analysis was applied to the transcribed data. RESULTS: Three main strategies were identified that informed the risk assessments and food choice practices of nut allergic individuals. These pertained to: (1 qualities of product such as the product category or the country of origin, (2 past experience of consuming a food product, and (3 sensory appreciation of risk. Risk reasoning and risk management behaviours were often contingent on the context and other physiological and socio-psychological needs which often competed with risk considerations. CONCLUSIONS: Understanding and taking into account the complexity of strategies and the influences of contextual factors will allow healthcare practitioners, allergy nutritionists, and caregivers to advise and educate patients more effectively in choosing foods safely. Governmental bodies and policy makers could also benefit from an understanding of these food choice strategies when risk management policies are designed and developed.

  7. Prefrontal spatial working memory network predicts animal's decision making in a free choice saccade task

    Mochizuki, Kei

    2015-01-01

    While neurons in the lateral prefrontal cortex (PFC) encode spatial information during the performance of working memory tasks, they are also known to participate in subjective behavior such as spatial attention and action selection. In the present study, we analyzed the activity of primate PFC neurons during the performance of a free choice memory-guided saccade task in which the monkeys needed to choose a saccade direction by themselves. In trials when the receptive field location was subsequently chosen by the animal, PFC neurons with spatially selective visual response started to show greater activation before cue onset. This result suggests that the fluctuation of firing before cue presentation prematurely biased the representation of a certain spatial location and eventually encouraged the subsequent choice of that location. In addition, modulation of the activity by the animal's choice was observed only in neurons with high sustainability of activation and was also dependent on the spatial configuration of the visual cues. These findings were consistent with known characteristics of PFC neurons in information maintenance in spatial working memory function. These results suggest that precue fluctuation of spatial representation was shared and enhanced through the working memory network in the PFC and could finally influence the animal's free choice of saccade direction. The present study revealed that the PFC plays an important role in decision making in a free choice condition and that the dynamics of decision making are constrained by the network architecture embedded in this cortical area. PMID:26490287

  8. Do pregnant women and their partners make an informed choice about first trimester risk assessment for Down syndrome, and are they satisfied with the choice?

    Bangsgaard, Louise; Tabor, Ann

    2012-01-01

    OBJECTIVE: All pregnant women in Denmark are offered risk assessment for Down syndrome. The aim of this study was to investigate whether women and partners make an informed choice about first trimester risk assessment, and their satisfaction with the choice. METHODS: A survey using multiple measure...... of knowledge (82% and 81%) and positive attitudes regarding risk assessment (97% and 98%), leading to 79% and 80% making an informed choice. Education predicted knowledge for women (odds ratio 3.42; 95% confidence interval 1.63-7.18) and partners (odds ratio 2.97; 95% confidence interval 1.37-6.45), country...... of origin predicted knowledge, attitude and informed choice among women. Three hundred thirty-two women (99%) and all partners were satisfied with having chosen risk assessment. CONCLUSIONS: Although 80% of pregnant women and partners make an informed choice about undergoing first trimester risk assessment...

  9. Perceived risks around choice and decision making at end-of-life: a literature review.

    Wilson, F; Gott, M; Ingleton, C

    2013-01-01

    the World Health Organization identifies meeting patient choice for care as central to effective palliative care delivery. Little is known about how choice, which implies an objective balancing of options and risks, is understood and enacted through decision making at end-of-life. to explore how perceptions of 'risk' may inform decision-making processes at end-of-life. an integrative literature review was conducted between January and February 2010. Papers were reviewed using Hawker et al.'s criteria and evaluated according to clarity of methods, analysis and evidence of ethical consideration. All literature was retained as background data, but given the significant international heterogeneity the final analysis specifically focused on the UK context. the databases Medline, PsycINFO, Assia, British Nursing Index, High Wire Press and CINAHL were explored using the search terms decision*, risk, anxiety, hospice and palliative care, end-of-life care and publication date of 1998-2010. thematic analysis of 25 papers suggests that decision making at end-of-life is multifactorial, involving a balancing of risks related to caregiver support; service provider resources; health inequalities and access; challenges to information giving; and perceptions of self-identity. Overall there is a dissonance in understandings of choice and decision making between service providers and service users. the concept of risk acknowledges the factors that shape and constrain end-of-life choices. Recognition of perceived risks as a central factor in decision making would be of value in acknowledging and supporting meaningful decision making processes for patients with palliative care needs and their families.

  10. Emotion regulation and risk taking: predicting risky choice in deliberative decision making.

    Panno, Angelo; Lauriola, Marco; Figner, Bernd

    2013-01-01

    Only very recently has research demonstrated that experimentally induced emotion regulation strategies (cognitive reappraisal and expressive suppression) affect risky choice (e.g., Heilman et al., 2010). However, it is unknown whether this effect also operates via habitual use of emotion regulation strategies in risky choice involving deliberative decision making. We investigated the role of habitual use of emotion regulation strategies in risky choice using the "cold" deliberative version of the Columbia Card Task (CCT; Figner et al., 2009). Fifty-three participants completed the Emotion Regulation Questionnaire (ERQ; Gross & John, 2003) and--one month later--the CCT and the PANAS. Greater habitual cognitive reappraisal use was related to increased risk taking, accompanied by decreased sensitivity to changes in probability and loss amount. Greater habitual expressive suppression use was related to decreased risk taking. The results show that habitual use of reappraisal and suppression strategies predict risk taking when decisions involve predominantly cognitive-deliberative processes.

  11. Making choices about medical interventions: the experience of disabled young people with degenerative conditions.

    Mitchell, Wendy A

    2014-04-01

    Current western policy, including the UK, advocates choice for service users and their families, taking greater control and being more involved in decision making. However, children's role in health decision making, especially from their own perspective, has received less research attention compared to doctors and parents' perspectives. To explore the perspective and experiences of disabled young people with degenerative conditions as they face significant medical interventions and engage in decision-making processes. Findings from a longitudinal qualitative study of 10 young people (13-22 years) with degenerative conditions are reported. Individual semi-structured interviews were conducted with participants over 3 years (2007-2010); the paper reports data from all three interview rounds. Interviews focused on medical intervention choices the young people identified as significant. Although the young people in this study felt involved in the medical intervention choices discussed, findings demonstrate a complex and diverse picture of decision making. Results highlighted different decisional roles adopted by the young people, the importance of information heuristics and working with other people whilst engaging in complex processes weighing up different decisional factors. Young people's experiences demonstrate the importance of moving beyond viewing health choices as technical or rational decisions. How each young person framed their decision was important. Recognizing this diversity and the importance of emerging themes, such as living a normal life, independence, fear of decisions viewed as 'irreversible' and the role of parents and peers in decision making highlights that, there are clear practice implications including, active practitioner listening, sensitivity and continued holistic family working. © 2012 John Wiley & Sons Ltd.

  12. Understanding patients’ decision-making strategies in hospital choice: Literature review and a call for experimental research

    Sophia Fischer

    2015-12-01

    Full Text Available Insights from psychology and cognitive science have, as yet, barely entered hospital choice research. This conceptual article closes this gap by reviewing and conceptually framing the current literature on hospital choice and patient information behavior and by discussing which tools are needed to advance scientific methodology in the study of patient decision-making strategies in hospital choice. Specifically, we make a call for more experimental research in hospital choice in order to complement existing theories, methods, and tools. This article introduces computerized process-tracing tools in hospital choice research, and also outlines a hands-on example, to provide a basis for future research.

  13. Beyond informed choice: Prenatal risk assessment, decision-making and trust

    Nete Schwennesen

    2008-05-01

    Full Text Available In 2004 prenatal risk assessment (PRA was implemented as a routine offer to all pregnant women in Denmark. It was argued that primarily the new programme would give all pregnant women an informed choice about whether to undergo prenatal testing. On the basis of ethnographic fieldwork in an ultrasound clinic in Denmark and interviews with pregnant women and their partners, we call into question the assumption underlying the new guidelines that more choice and more objective information is a source of empowerment and control. We focus on one couple's experience of PRA. This case makes it evident how supposed choices in the context of PRA may not be experienced as such. Rather, they are experienced as complicated processes of meaning-making in the relational space between the clinical setting, professional authority and the social life of the couples. PRA users are reluctant to make choices and abandon health professionals as authoritative experts in the face of complex risk knowledge. When assumptions about autonomy and self-determination are inscribed into the social practice of PRA, authority is transferred to the couple undergoing PRA and a new configuration of responsibility evolves between the couple and their relationship to the foetus. It is argued that al-though the new programme of prenatal testing in Denmark presents itself in opposition to quasi-eugenic and paternalistic forms of governing couples' decisions it represents another form of government that works through the notion of choice. An ethics of a shared responsibility of PRA and its outcome would be more in agreement with how decisions are actually made.http://dx.doi.org/10.5324/eip.v2i1.1687

  14. Risky decision-making under risk in schizophrenia: A deliberate choice?

    Pedersen, Anya; Göder, Robert; Tomczyk, Samuel; Ohrmann, Patricia

    2017-09-01

    Patients with schizophrenia reveal impaired decision-making strategies causing social, financial and health care problems. The extent to which deficits in decision-making reflect intentional risky choices in schizophrenia is still under debate. Based on previous studies we expected patients with schizophrenia to reveal a riskier performance on the GDT and to make more disadvantageous decisions on the IGT. In the present study, we investigated 38 patients with schizophrenia and 38 matched healthy control subjects with two competing paradigms regarding feedback: (1) The Game of Dice Task (GDT), in which the probabilities of winning or losing are stable and explicitly disclosed to the subject, to assess decision-making under risk and (2) the Iowa Gambling Task (IGT), which requires subjects to infer the probabilities of winning or losing from feedback, to investigate decision-making under ambiguity. Patients with schizophrenia revealed an overall riskier performance on the GDT; although they adjusted their strategy over the course of the GDT, they still made significantly more disadvantageous choices than controls. More positive symptoms in patients with schizophrenia indicated by higher PANSS positive scores were associated with riskier choices and less use of negative feedback. Compared to healthy controls, they were not impaired in net score but chose more disadvantageous cards than controls on the first block of the IGT. Effects of medication at the time of testing cannot be ruled out. Our findings suggest that patients with schizophrenia make riskier decisions and are less able to regulate their decision-making to implement advantageous strategies, even when the probabilities of winning or losing are explicitly disclosed. The dissociation between performance on the GDT and IGT suggests a pronounced impairment of executive functions related to the dorsolateral prefrontal cortex. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Evidence Accumulation and Choice Maintenance Are Dissociated in Human Perceptual Decision Making.

    Mads Lund Pedersen

    Full Text Available Perceptual decision making in monkeys relies on decision neurons, which accumulate evidence and maintain choices until a response is given. In humans, several brain regions have been proposed to accumulate evidence, but it is unknown if these regions also maintain choices. To test if accumulator regions in humans also maintain decisions we compared delayed and self-paced responses during a face/house discrimination decision making task. Computational modeling and fMRI results revealed dissociated processes of evidence accumulation and decision maintenance, with potential accumulator activations found in the dorsomedial prefrontal cortex, right inferior frontal gyrus and bilateral insula. Potential maintenance activation spanned the frontal pole, temporal gyri, precuneus and the lateral occipital and frontal orbital cortices. Results of a quantitative reverse inference meta-analysis performed to differentiate the functions associated with the identified regions did not narrow down potential accumulation regions, but suggested that response-maintenance might rely on a verbalization of the response.

  16. Seeking balance: the complexity of choice-making among academic surgeons.

    Brown, Judith Belle; Fluit, Meghan; Lent, Barbara; Herbert, Carol

    2011-10-01

    This study describes the experiences of academic surgeons in seeking a balance between their personal and professional lives. This phenomenological study, conducted in 2009-2010 at the University of Western Ontario, used in-depth individual semistructured interviews to explore the ideas, perceptions, and experiences of 17 recently recruited academic surgeons (nine women/eight men) about seeking balance between their personal and professional lives. All the interviews were audiotaped and transcribed verbatim. The data analysis was both iterative and interpretative. All the participants expressed a passion and commitment to academic surgery, but their stories revealed the complexity of making choices in seeking a balance between their personal and professional lives. This process of making choices was filtered through influential values in their lives, which in turn determined how they set boundaries to protect their personal and family time from the demands of their professional obligations. Intertwined in this process were the trade-offs they had to make in order to seek balance. Some choices, boundary-setting strategies, and trade-offs were dictated by gender. Finally, the process of making choices was not static; instead, the data revealed how it was both dynamic and cyclical, requiring reexamination over the life cycle, as well as their career trajectory. Thus, seeking a balance was an ever-changing process. Understanding how members of an academic department of surgery navigate the balance between their personal and professional worlds may provide new insights for other disciplines seeking to enhance the development of the next generation of academics.

  17. Developing and pilot testing a shared decision-making intervention for dialysis choice.

    Finderup, Jeanette; Jensen, Jens K D; Lomborg, Kirsten

    2018-04-17

    Evidence is inconclusive on how best to guide the patient in decision-making around haemodialysis and peritoneal dialysis choice. International guidelines recommend involvement of the patient in the decision to choose the dialysis modality most suitable for the individual patient. Nevertheless, studies have shown lack of involvement of the patient in decision-making. To develop and pilot test an intervention for shared decision-making targeting the choice of dialysis modality. This study reflects the first two phases of a complex intervention design: phase 1, the development process and phase 2, feasibility and piloting. Because decision aids were a part of the intervention, the International Patient Decision Aid Standards were considered. The pilot test included both the intervention and the feasibility of the validated shared decision-making questionnaire (SDM Q9) and the Decision Quality Measure (DQM) applied to evaluate the intervention. A total of 137 patients tested the intervention. After the intervention, 80% of the patients chose dialysis at home reflecting an increase of 23% in starting dialysis at home prior to the study. The SDM Q9 showed the majority of the patients experienced this intervention as shared decision-making. An intervention based on shared decision-making supported by decision aids seemed to increase the number of patients choosing home dialysis. The SDM Q9 and DQM were feasible evaluation tools. Further research is needed to gain insight into the patients' experiences of involvement and the implications for their choice of dialysis modality. © 2018 European Dialysis and Transplant Nurses Association/European Renal Care Association.

  18. The Nature of Belief-Directed Exploratory Choice in Human Decision-Making

    W. Bradley Knox

    2012-01-01

    Full Text Available In non-stationary environments, there is a conflict between exploiting currently favored options and gaining information by exploring lesser-known options that in the past have proven less rewarding. Optimal decision making in such tasks requires considering future states of the environment (i.e., planning and properly updating beliefs about the state of environment after observing outcomes associated with choices. Optimal belief-updating is reflective in that beliefs can change without directly observing environmental change. For example, after ten seconds elapse, one might correctly believe that a traffic light last observed to be red is now more likely to be green. To understand human decision-making when rewards associated with choice options change over time, we develop a variant of the classic bandit task that is both rich enough to encompass relevant phenomena and sufficiently tractable to allow for ideal actor analysis of sequential choice behavior. We evaluate whether people update beliefs about the state of environment in a reflexive (i.e., only in response to observed changes in reward structure or reflective manner. In contrast to purely "random" accounts of exploratory behavior, model-based analyses of the subjects’ choices and latencies indicate that people are reflective belief-updaters. However, unlike the Ideal Actor model, our analyses indicate that people's choice behavior does not reflect consideration of future environmental states. Thus, although people update beliefs in a reflective manner consistent with the ideal actor, they do not engage in optimal long-term planning, but instead myopically choose the option on every trial that is believed to have the highest immediate payoff.

  19. The Nature of Belief-Directed Exploratory Choice in Human Decision-Making

    Knox, W. Bradley; Otto, A. Ross; Stone, Peter; Love, Bradley C.

    2011-01-01

    In non-stationary environments, there is a conflict between exploiting currently favored options and gaining information by exploring lesser-known options that in the past have proven less rewarding. Optimal decision-making in such tasks requires considering future states of the environment (i.e., planning) and properly updating beliefs about the state of the environment after observing outcomes associated with choices. Optimal belief-updating is reflective in that beliefs can change without directly observing environmental change. For example, after 10 s elapse, one might correctly believe that a traffic light last observed to be red is now more likely to be green. To understand human decision-making when rewards associated with choice options change over time, we develop a variant of the classic “bandit” task that is both rich enough to encompass relevant phenomena and sufficiently tractable to allow for ideal actor analysis of sequential choice behavior. We evaluate whether people update beliefs about the state of environment in a reflexive (i.e., only in response to observed changes in reward structure) or reflective manner. In contrast to purely “random” accounts of exploratory behavior, model-based analyses of the subjects’ choices and latencies indicate that people are reflective belief updaters. However, unlike the Ideal Actor model, our analyses indicate that people’s choice behavior does not reflect consideration of future environmental states. Thus, although people update beliefs in a reflective manner consistent with the Ideal Actor, they do not engage in optimal long-term planning, but instead myopically choose the option on every trial that is believed to have the highest immediate payoff. PMID:22319503

  20. Sensorimotor learning biases choice behavior: a learning neural field model for decision making.

    Christian Klaes

    Full Text Available According to a prominent view of sensorimotor processing in primates, selection and specification of possible actions are not sequential operations. Rather, a decision for an action emerges from competition between different movement plans, which are specified and selected in parallel. For action choices which are based on ambiguous sensory input, the frontoparietal sensorimotor areas are considered part of the common underlying neural substrate for selection and specification of action. These areas have been shown capable of encoding alternative spatial motor goals in parallel during movement planning, and show signatures of competitive value-based selection among these goals. Since the same network is also involved in learning sensorimotor associations, competitive action selection (decision making should not only be driven by the sensory evidence and expected reward in favor of either action, but also by the subject's learning history of different sensorimotor associations. Previous computational models of competitive neural decision making used predefined associations between sensory input and corresponding motor output. Such hard-wiring does not allow modeling of how decisions are influenced by sensorimotor learning or by changing reward contingencies. We present a dynamic neural field model which learns arbitrary sensorimotor associations with a reward-driven Hebbian learning algorithm. We show that the model accurately simulates the dynamics of action selection with different reward contingencies, as observed in monkey cortical recordings, and that it correctly predicted the pattern of choice errors in a control experiment. With our adaptive model we demonstrate how network plasticity, which is required for association learning and adaptation to new reward contingencies, can influence choice behavior. The field model provides an integrated and dynamic account for the operations of sensorimotor integration, working memory and action

  1. The dynamics of decision making in risky choice: An Eye-tracking Analysis

    Susann eFiedler

    2012-10-01

    Full Text Available In the last years, research on risky choice has moved beyond analyzing choices only. Models have been suggested that aim to describe the underlying cognitive processes and some studies have tested process predictions of these models. Prominent approaches are evidence accumulation models such as Decision Field Theory (DFT, simple serial heuristic models such as the Adaptive Toolbox, and connectionist approaches such as the Parallel Constraint Satisfaction Model (PCS. In two studies involving measures of attention and pupil dilation, we investigate hypotheses derived from these models in choices between two gambles with two outcomes each. We show that attention to an outcome of a gamble increases with its probability and its value and that attention shifts towards the subsequently favored gamble after about two thirds of the decision process, indicating a gaze-cascade effect. Information search occurs mostly within gambles, and the direction of search does not change over the course of decision making. Pupil dilation, which reflects both cognitive effort and arousal, increases during the decision process and increases with mean Expected Value. Overall, the results support aspects of automatic integration models for risky choice such as DFT and PCS, but in their current specification none of them can account for the full pattern of results.

  2. The dynamics of decision making in risky choice: an eye-tracking analysis.

    Fiedler, Susann; Glöckner, Andreas

    2012-01-01

    In the last years, research on risky choice has moved beyond analyzing choices only. Models have been suggested that aim to describe the underlying cognitive processes and some studies have tested process predictions of these models. Prominent approaches are evidence accumulation models such as decision field theory (DFT), simple serial heuristic models such as the adaptive toolbox, and connectionist approaches such as the parallel constraint satisfaction (PCS) model. In two studies involving measures of attention and pupil dilation, we investigate hypotheses derived from these models in choices between two gambles with two outcomes each. We show that attention to an outcome of a gamble increases with its probability and its value and that attention shifts toward the subsequently favored gamble after about two thirds of the decision process, indicating a gaze-cascade effect. Information search occurs mostly within-gambles, and the direction of search does not change over the course of decision making. Pupil dilation, which reflects both cognitive effort and arousal, increases during the decision process and increases with mean expected value. Overall, the results support aspects of automatic integration models for risky choice such as DFT and PCS, but in their current specification none of them can account for the full pattern of results.

  3. Mental toughness in soccer

    Diment, Gregory Michael

    2014-01-01

    a systematic observation checklist of mental toughness behavior in professional soccer. Consistent with existing studies, the results created a systematic observation instrument containing 15 mental toughness behaviors. Practical implications include goal-setting, game analysis and self-modeling interventions...

  4. Making an informed choice in the catering environment: what do consumers want to know?

    Mackison, D; Wrieden, W L; Anderson, A S

    2009-12-01

    Eating outside the home is common in the UK, but it remains difficult for consumers to make informed choices based on menu information. The present study examines the reported preferences for the provision of nutrition (salt, fat and energy) and ingredient information in six types of UK catering outlets. Participants completed a short postal survey, assessing their frequency of dining at specific catering establishments as well as their desire to see nutrition and ingredient information. The responses from 786 adults aged >or=18 years (of whom 65% claimed to be 'motivated to eat a healthy diet') indicated that over 40% reported eating at a catering outlet at least once a week. Over half said that they would wish to see information on ingredients and the salt content of menu items at all venues. Preference for information on energy and fat content was less popular and varied in the range 42-56% for energy and 47-59% for fat. It is notable that 43% of respondents said they would welcome information on energy content of menu items in restaurants. A significant proportion of consumers wish to see information on the ingredients and nutrition composition on menu items for sale in UK catering outlets. Such information is likely to raise an awareness and understanding of healthy food choices and assist the population in making informed choices about healthy eating.

  5. Time Is Money: The Decision Making of Smartphone High Users in Gain and Loss Intertemporal Choice.

    Tang, Zixuan; Zhang, Huijun; Yan, An; Qu, Chen

    2017-01-01

    Nowadays the smartphone plays an important role in our lives. While it brings us convenience and efficiency, its overuse can cause problems. Although a great number of studies have demonstrated that people affected by substance abuse, pathological gambling, and internet addiction disorder have lower self-control than average, scarcely any study has investigated the decision making of smartphone high users by using a behavioral paradigm. The present study employed an intertemporal task, the Smartphone Addiction Inventory (SPAI) and the Barratt Impulsiveness Scale 11th version (BIS-11) to explore the decision control of smartphone high users in a sample of 125 college students. Participants were divided into three groups according to their SPAI scores. The upper third (69 or higher), middle third (from 61 to 68) and lower third (60 or lower) of scores were defined as high smartphone users, medium users and low users, respectively. We compared the percentage of small immediate reward/penalty choices in different conditions between the three groups. Relative to the low users group, high users and medium users were more inclined to request an immediate monetary reward. Moreover, for the two dimensions of time and money in intertemporal choice, high users and medium users showed a bias in intertemporal choice task among most of the time points and value magnitude compared to low users. These findings demonstrated that smartphone overuse was associated with problematic decision-making, a pattern similar to that seen in persons affected by a variety of addictions.

  6. Testing Ecological Theories of Offender Spatial Decision Making Using a Discrete Choice Model

    Summers, Lucia

    2015-01-01

    Research demonstrates that crime is spatially concentrated. However, most research relies on information about where crimes occur, without reference to where offenders reside. This study examines how the characteristics of neighborhoods and their proximity to offender home locations affect offender spatial decision making. Using a discrete choice model and data for detected incidents of theft from vehicles (TFV), we test predictions from two theoretical perspectives—crime pattern and social disorganization theories. We demonstrate that offenders favor areas that are low in social cohesion and closer to their home, or other age-related activity nodes. For adult offenders, choices also appear to be influenced by how accessible a neighborhood is via the street network. The implications for criminological theory and crime prevention are discussed. PMID:25866412

  7. Testing Ecological Theories of Offender Spatial Decision Making Using a Discrete Choice Model.

    Johnson, Shane D; Summers, Lucia

    2015-04-01

    Research demonstrates that crime is spatially concentrated. However, most research relies on information about where crimes occur, without reference to where offenders reside. This study examines how the characteristics of neighborhoods and their proximity to offender home locations affect offender spatial decision making. Using a discrete choice model and data for detected incidents of theft from vehicles (TFV) , we test predictions from two theoretical perspectives-crime pattern and social disorganization theories. We demonstrate that offenders favor areas that are low in social cohesion and closer to their home, or other age-related activity nodes. For adult offenders, choices also appear to be influenced by how accessible a neighborhood is via the street network. The implications for criminological theory and crime prevention are discussed.

  8. Developing and pilot testing a shared decision-making intervention for dialysis choice

    Finderup, Jeanette; Jensen, Jens Dam; Lomborg, Kirsten

    2018-01-01

    . Nevertheless, studies have shown lack of involvement of the patient in decision-making. Objectives: To develop and pilot test an intervention for shared decision-making targeting the choice of dialysis modality. Methods: This study reflects the first two phases of a complex intervention design: phase 1......, the development process and phase 2, feasibility and piloting. Because decision aids were a part of the intervention, the International Patient Decision Aid Standards were considered. The pilot test included both the intervention and the feasibility of the validated shared decision-making questionnaire (SDM Q9......) and the Decision Quality Measure (DQM) applied to evaluate the intervention. Results: A total of 137 patients tested the intervention. After the intervention, 80% of the patients chose dialysis at home reflecting an increase of 23% in starting dialysis at home prior to the study. The SDM Q9 showed the majority...

  9. Risky decision-making is associated with residential choice in healthy older adults.

    Kendra L Seaman

    2015-08-01

    Full Text Available As our society becomes more mobile and people reside farther away from their immediate families, competent decision-making has become critical for the older adults wishing to maintain their independence. However, very little is known about the relationship between residential choice and decision making. Here we use the Balloon Analogue Risk Task (BART to examine risk-taking in two samples of older adults, one living in a retirement community and another living independently. We also used a cognitive model to gain insight into the cognitive factors underlying decision-making in these groups. We found that older adults living in a retirement community were more risk averse than their independent counterparts. Furthermore, this difference appeared to be motivated by group differences in initial perception of risk. This study suggests an intriguing difference between these two residential groups, and also points to the utility of using laboratory methods in research on real-world problems.

  10. Risky decision-making is associated with residential choice in healthy older adults.

    Seaman, Kendra L; Stillman, Chelsea M; Howard, Darlene V; Howard, James H

    2015-01-01

    As our society becomes more mobile and people reside farther away from their immediate families, competent decision-making has become critical for the older adults wishing to maintain their independence. However, very little is known about the relationship between residential choice and decision-making. Here we use the Balloon Analog Risk Task (BART) to examine risk-taking in two samples of older adults, one living in a retirement community and another living independently. We also used a cognitive model to gain insight into the cognitive factors underlying decision-making in these groups. We found that older adults living in a retirement community were more risk averse than their independent counterparts. Furthermore, this difference appeared to be motivated by group differences in initial perception of risk. This study suggests an intriguing difference between these two residential groups, and also points to the utility of using laboratory methods in research on real-world problems.

  11. Neural antecedents of social decision-making in a partner choice task.

    Cartmell, Samuel C D; Chun, Marvin M; Vickery, Timothy J

    2014-11-01

    Experiments in financial decision-making point to two complementary processes that encode prospective gain and loss preceding the choice to purchase consumer goods. These processes involve the nucleus accumbens (NAcc) and the right anterior insula, respectively. The current experiment used functional MRI to investigate whether these regions served a similar function during an analogous social decision-making task without the influence of monetary outcomes. In this task, subjects chose partners based on face stimuli of varying attractiveness (operationalizing value) and ratings of compatibility with the participant (operationalizing likelihood of rejection). The NAcc responded to anticipated gain; the right anterior insula responded to compatibility, but not in a manner that suggests an analogy to anticipated cost. Logistic regression modeling demonstrated that both regions predicted subsequent choice above and beyond the influence of group attractiveness ratings or compatibility alone. Although the function of the insula may differ between tasks, these results suggest that financial and social decision-making recruit a similar network of brain regions. © The Author (2013). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

  12. [Influenza A from the rational choice theory: proposals for decision making in prevention policies].

    Peña, Francisco Garrido; Fernández, Luís Andrés López; García, Eugenia Gil

    2009-01-01

    This article is a reflection on the social uncertainty caused by Influenza A and on the consequences that it can have on decision making in health promotion policies. We use concepts and metaphors of the Rational Choice Theory, among them, the "in gratitude effect" or the "distrust effect", as we analyse how these can become obstacles for the efficiency of prevention policies. Then, we focus on the information asymmetry of the principal-agent relationship, and we propose measures to diminish the "moral risk" that they cause. We finish by advancing some proposals for designing lines and strategies of action in health promotion policies.

  13. Usefulness of the discrete choice methodology for marketing decision-making in New Product Development

    Krystallis, Athanasios; Linadrakis, M.; Mamalis, S.

    2010-01-01

    functional children's snacks marketed in Greece. Using a very simple discrete choice experimental design, the authors aim (a) to provide an example of consumer research implementation in food-related NPD and to assess its marketing value, and (b) to evaluate the quality of the acquired consumer......-related information for marketing decision-making in food consumer-led NPD processes against a number of criteria set in the relevant literature. ''Functionality'' is found to be a statistically significant attribute for all three children's snacks of the research design compared to other attributes such as flavor...

  14. Decision making under internal uncertainty: the case of multiple-choice tests with different scoring rules.

    Bereby-Meyer, Yoella; Meyer, Joachim; Budescu, David V

    2003-02-01

    This paper assesses framing effects on decision making with internal uncertainty, i.e., partial knowledge, by focusing on examinees' behavior in multiple-choice (MC) tests with different scoring rules. In two experiments participants answered a general-knowledge MC test that consisted of 34 solvable and 6 unsolvable items. Experiment 1 studied two scoring rules involving Positive (only gains) and Negative (only losses) scores. Although answering all items was the dominating strategy for both rules, the results revealed a greater tendency to answer under the Negative scoring rule. These results are in line with the predictions derived from Prospect Theory (PT) [Econometrica 47 (1979) 263]. The second experiment studied two scoring rules, which allowed respondents to exhibit partial knowledge. Under the Inclusion-scoring rule the respondents mark all answers that could be correct, and under the Exclusion-scoring rule they exclude all answers that might be incorrect. As predicted by PT, respondents took more risks under the Inclusion rule than under the Exclusion rule. The results illustrate that the basic process that underlies choice behavior under internal uncertainty and especially the effect of framing is similar to the process of choice under external uncertainty and can be described quite accurately by PT. Copyright 2002 Elsevier Science B.V.

  15. Is decision-making ability related to food choice and facets of eating behaviour in adolescents?

    Macchi, Rosemarie; MacKew, Laura; Davis, Caroline

    2017-09-01

    To test the prediction that poor decision-making would predict poor eating-related behaviours, which in turn would relate to elevated body mass index (BMI) percentile. Associations among decision-making ability, eating behaviours, and BMI percentile were examined in a sample of 311 healthy male and female adolescents, aged 14-18 years. Structural equation modelling was used to test the proposed relationships. The predicted model was a good fit to the data and all paths between latent and indicator variables were significant. Impulsive responding significantly predicted poor food choice and overeating. No significant relationships emerged between eating-related variables and BMI percentile. Findings from this study extend the existing research in adults and offer a more comprehensive understanding of factors that may contribute to eating behaviours and weight status in teenagers. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. The effects of team expert choice on group decision-making in collaborative new product development; a pilot study

    Hummel, J. Marjan; van Rossum, Wouter; Verkerke, Gijsbertus Jacob; Rakhorst, G.

    2000-01-01

    This study analyses the effects of Team Expert Choice on group decision-making in collaborative new product development. We applied Team Expert Choice to support a product evaluation conducted by a new product development group composed of professionally diverse members. The evaluation resulted in

  17. Survival or Mortality : Does Risk Attribute Framing Influence Decision-Making Behavior in a Discrete Choice Experiment?

    Veldwijk, Jorien; Essers, Brigitte A B; Lambooij, Mattijs S; Dirksen, Carmen D; Smit, Henriette A; de Wit, G Ardine

    2016-01-01

    OBJECTIVE: To test how attribute framing in a discrete choice experiment (DCE) affects respondents' decision-making behavior and their preferences. METHODS: Two versions of a DCE questionnaire containing nine choice tasks were distributed among a representative sample of the Dutch population aged 55

  18. Drivers’ decision-making when attempting to cross an intersection results from choice between affordances

    Geoffrey eMARTI

    2015-01-01

    Full Text Available In theory, a safe approach to an intersection implies that the driver can simultaneously manage two scenarios: they either cross or they must give way to an oncoming vehicle. In this article we formalize the critical time for safe crossing (CTcross and the critical time for safe stopping (CTstop to represent crossing and stopping possibilities, respectively. We describe these critical times in terms of affordances and empirically test their respective contribution to the driver’s decision-making process. Using a driving simulator, three groups of participants drove cars with identical acceleration capabilities and different braking capabilities. They were asked to try to cross an intersection where there was an oncoming vehicle, if they deemed the maneuver to be safe. If not, they could decide to stop or, as a last resort, make an emergency exit. The intersections were identical among groups.Results showed that although the crossing possibilities (CTcross were the same for all groups, there were between-group differences in crossing frequency. This suggests that stopping possibilities (CTstop play a role in the driver’s decision-making process, in addition to the crossing possibilities. These results can be accounted for by a behavioral model of decision making, and provide support for the hypothesis of choice between affordances.

  19. Attention and choice: a review on eye movements in decision making.

    Orquin, Jacob L; Mueller Loose, Simone

    2013-09-01

    This paper reviews studies on eye movements in decision making, and compares their observations to theoretical predictions concerning the role of attention in decision making. Four decision theories are examined: rational models, bounded rationality, evidence accumulation, and parallel constraint satisfaction models. Although most theories were confirmed with regard to certain predictions, none of the theories adequately accounted for the role of attention during decision making. Several observations emerged concerning the drivers and down-stream effects of attention on choice, suggesting that attention processes plays an active role in constructing decisions. So far, decision theories have largely ignored the constructive role of attention by assuming that it is entirely determined by heuristics, or that it consists of stochastic information sampling. The empirical observations reveal that these assumptions are implausible, and that more accurate assumptions could have been made based on prior attention and eye movement research. Future decision making research would benefit from greater integration with attention research. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. Making pragmatic choices: women’s experiences of delivery care in Northern Ethiopia

    Gebrehiwot Tesfay

    2012-10-01

    Full Text Available Abstract Background In 2003, the Ethiopian Ministry of Health launched the Health Extension Programme (HEP, which was intended to increase access to reproductive health care. Despite enormous effort, utilization of maternal health services remains limited, and the reasons for the low utilization of the services offered through the HEP previously have not been explored in depth. This study explores women’s experiences and perceptions regarding delivery care in Tigray, a northern region of Ethiopia, and enables us to make suggestions for better implementation of maternal health care services in this setting. Methods We used six focus group discussions with 51 women to explore perceptions and experiences regarding delivery care. The data were analysed by means of grounded theory. Results One core category emerged, ‘making pragmatic choices’, which connected the categories ‘aiming for safer deliveries’, ‘embedded in tradition’, and ‘medical knowledge under constrained circumstances’. In this setting, women – aiming for safer deliveries – made choices pragmatically between the two available models of childbirth. On the one hand, choice of home delivery, represented by the category ‘embedded in tradition’, was related to their faith, the ascendancy of elderly women, the advantages of staying at home and the custom of traditional birth attendants (TBAs. On the other, institutional delivery, represented by the category ‘medical knowledge under constrained circumstances’, and linked to how women appreciated medical resources and the support of health extension workers (HEWs but were uncertain about the quality of care, emphasized the barriers to transportation. In Tigray women made choices pragmatically and seemed to not feel any conflict between the two available models, being supported by traditional birth attendants, HEWs and husbands in their decision-making. Representatives of the two models were not as open to

  1. Value for money or making the healthy choice: the impact of proportional pricing on consumers' portion size choices.

    Vermeer, Willemijn M; Alting, Esther; Steenhuis, Ingrid H M; Seidell, Jacob C

    2010-02-01

    Large food portion sizes are determinants of a high caloric intake, especially if they have been made attractive through value size pricing (i.e. lower unit prices for large than for small portion sizes). The purpose of the two questionnaire studies that are reported in this article was to assess the impact of proportional pricing (i.e. removing beneficial prices for large sizes) on people's portion size choices of high caloric food and drink items. Both studies employed an experimental design with a proportional pricing condition and a value size pricing condition. Study 1 was conducted in a fast food restaurant (N = 150) and study 2 in a worksite cafeteria (N = 141). Three different food products (i.e. soft drink, chicken nuggets in study 1 and a hot meal in study 2) with corresponding prices were displayed on pictures in the questionnaire. Outcome measures were consumers' intended portion size choices. No main effects of pricing were found. However, confronted with proportional pricing a trend was found for overweight fast food restaurant visitors being more likely to choose small portion sizes of chicken nuggets (OR = 4.31, P = 0.07) and less likely to choose large soft drink sizes (OR = 0.07, P = 0.04). Among a general public, proportional pricing did not reduce consumers' size choices. However, pricing strategies can help overweight and obese consumers selecting appropriate portion sizes of soft drink and high caloric snacks. More research in realistic settings with actual behaviour as outcome measure is required.

  2. What would Batman eat?: priming children to make healthier fast food choices.

    Wansink, B; Shimizu, M; Camps, G

    2012-04-01

    Fast food patronage is a frequent reality for many children and their parents. Although there are increasingly healthier alternatives for popular menu items (apple slices instead of French fries), they are infrequently selected. We investigated whether either of two priming tactics - the priming of a role model's food choices or the priming of healthy foods - could influence children to make healthier fast food choices. In the priming model condition, 22 children (ranging in age from 6 to 12 years) were presented with 12 photos of 6 admirable and 6 less admirable models and asked, 'Would this person order apple fries or French fries?' In the health prime condition, the same children were shown 12 photos of 6 healthy foods and 6 less healthy foods and asked to indicate if each food was healthy or unhealthy. When children were asked what various admirable people - such as Batman or Spiderman - would eat, 45% chose apple slices over French fries, which was higher than the health prime (P < 0.001) or the control condition (P < 0.001). Advising a parent to ask their child 'What would Batman (or another admired character or person) eat?' might be an easy step to take in what could be a healthier fast food world. © 2012 The Authors. Pediatric Obesity © 2012 International Association for the Study of Obesity.

  3. Insights from triangulation of two purchase choice elicitation methods to predict social decision making in healthcare.

    Whitty, Jennifer A; Rundle-Thiele, Sharyn R; Scuffham, Paul A

    2012-03-01

    Discrete choice experiments (DCEs) and the Juster scale are accepted methods for the prediction of individual purchase probabilities. Nevertheless, these methods have seldom been applied to a social decision-making context. To gain an overview of social decisions for a decision-making population through data triangulation, these two methods were used to understand purchase probability in a social decision-making context. We report an exploratory social decision-making study of pharmaceutical subsidy in Australia. A DCE and selected Juster scale profiles were presented to current and past members of the Australian Pharmaceutical Benefits Advisory Committee and its Economic Subcommittee. Across 66 observations derived from 11 respondents for 6 different pharmaceutical profiles, there was a small overall median difference of 0.024 in the predicted probability of public subsidy (p = 0.003), with the Juster scale predicting the higher likelihood. While consistency was observed at the extremes of the probability scale, the funding probability differed over the mid-range of profiles. There was larger variability in the DCE than Juster predictions within each individual respondent, suggesting the DCE is better able to discriminate between profiles. However, large variation was observed between individuals in the Juster scale but not DCE predictions. It is important to use multiple methods to obtain a complete picture of the probability of purchase or public subsidy in a social decision-making context until further research can elaborate on our findings. This exploratory analysis supports the suggestion that the mixed logit model, which was used for the DCE analysis, may fail to adequately account for preference heterogeneity in some contexts.

  4. Simon`s Puzzle: Heuristics in the Process of Making Political Choices

    Mateusz Wajzer

    2014-07-01

    Full Text Available In this article we analyse one of the most fascinating paradoxes of mass politics. Based on the data from the studies of neurobiologists, neurologists, social psychology, cognitive and evolution studies we answer the question specified in literature as the Simon’s puzzle: How is it possible that citizens have their opinions about politics, if they know so little about it? We began our analysis from the criticism of the economic rationality approach. To do this, we referred to the Allais paradox, cognitive dissonance theory, Ellsberg paradox, the concept of bounded rationality, conjunction fallacy and prospect theory. Next, we described the evolutionary processes shaping the minds of Homo sapiens and characterised cognitive mechanisms, thanks to which people can make political choices, especially in view of the shortage of time and information. The following heuristics are referred to herein: affect, recognition, judgment and imitation.

  5. Searching Choices: Quantifying Decision-Making Processes Using Search Engine Data.

    Moat, Helen Susannah; Olivola, Christopher Y; Chater, Nick; Preis, Tobias

    2016-07-01

    When making a decision, humans consider two types of information: information they have acquired through their prior experience of the world, and further information they gather to support the decision in question. Here, we present evidence that data from search engines such as Google can help us model both sources of information. We show that statistics from search engines on the frequency of content on the Internet can help us estimate the statistical structure of prior experience; and, specifically, we outline how such statistics can inform psychological theories concerning the valuation of human lives, or choices involving delayed outcomes. Turning to information gathering, we show that search query data might help measure human information gathering, and it may predict subsequent decisions. Such data enable us to compare information gathered across nations, where analyses suggest, for example, a greater focus on the future in countries with a higher per capita GDP. We conclude that search engine data constitute a valuable new resource for cognitive scientists, offering a fascinating new tool for understanding the human decision-making process. Copyright © 2016 The Authors. Topics in Cognitive Science published by Wiley Periodicals, Inc. on behalf of Cognitive Science Society.

  6. Social value and individual choice: The value of a choice-based decision-making process in a collectively funded health system.

    Espinoza, Manuel Antonio; Manca, Andrea; Claxton, Karl; Sculpher, Mark

    2018-02-01

    Evidence about cost-effectiveness is increasingly being used to inform decisions about the funding of new technologies that are usually implemented as guidelines from centralized decision-making bodies. However, there is also an increasing recognition for the role of patients in determining their preferred treatment option. This paper presents a method to estimate the value of implementing a choice-based decision process using the cost-effectiveness analysis toolbox. This value is estimated for 3 alternative scenarios. First, it compares centralized decisions, based on population average cost-effectiveness, against a decision process based on patient choice. Second, it compares centralized decision based on patients' subgroups versus an individual choice-based decision process. Third, it compares a centralized process based on average cost-effectiveness against a choice-based process where patients choose according to a different measure of outcome to that used by the centralized decision maker. The methods are applied to a case study for the management of acute coronary syndrome. It is concluded that implementing a choice-based process of treatment allocation may be an option in collectively funded health systems. However, its value will depend on the specific health problem and the social values considered relevant to the health system. Copyright © 2017 John Wiley & Sons, Ltd.

  7. "You have to be careful who you talk to and what you say …" - on psychosis and making rational choices.

    Topor, Alain; Di Girolamo, Simonetta

    2010-12-01

    People who have been diagnosed with schizophrenia are regarded as being no longer capable of making rational choices. Fifteen users with psychosis diagnosis participated to 10 focus group sessions about different aspects of everyday life. The discussions were tape recorded and the transcript analyzed using a grounded theory inspired methodology. A core category that emerged was making choices in crises situations. Users have to choose whether or not they want help, to whom to turn for help, and how to describe their problems so as to get the kind of help they seek. The choices were based on past experiences in connection with the choices available. They were constantly making quality judgements of the care workers they came into contact with. Experiencing a sense of comradeship emerged as a vital criterion. The ability to make rational choices often existed parallel with hallucinations and delusions. This ability could form the basis for a true collaboration between users and professionals. The findings of this study indicate that such collaboration is possible, but that it requires a reassessment of our traditional knowledge base.

  8. Color Choice is Everything - Impacts Color makes to the Lighting Environment

    Clark, Toni A.

    2012-01-01

    When contracts are let out to design multiple systems in a vehicle, it is a challenge to maintain integration between system leads. Designers on niche systems, like lighting and control panel design, often get caught up in the challenge of designing the light source or visual interface and fail to include time in their schedule to work with system architects on how their lighting system will be integrated. Additionally, behavioral scientists, industrial designers, and materials engineers get caught up with the materials and look of the system, but often fail to consider how the selection of their materials could affect the certification or performance of electronic devices like lighting systems. Additionally, computer modeling of the system architecture often assumes a perfect environment without the clutter of actual human use (dirt, stowage, crowding). As a result, lighting systems, and backlit displays run the risk of being overdesigned or under designed. Engineers making the assumption that because they have no input or there is no requirement on work surface reflectance, make the assumption that they can t count on good material choices and thus may install more lighting than is necessary. While having more lights may seem better, for a vehicle that is trying to conserve power, more lights may not be a good option. On the other hand, designers who made the opposite assumption and designed a lighting system that only produced just enough light, often wind up with a system that did conserve power, but didn t produce enough light. These situations are exasperated when the system starts to be used and the models are not perfect anymore. The lack of coordination and iterative design not only can impact lighting levels within an environment, but also can affect color perception. This is because, if materials do not represent a gradation of white or black, the material unevenly absorbs and reflects light at different wavelengths of the visual spectrum. The lighting

  9. Design and protocol of a randomized multiple behavior change trial: Make Better Choices 2 (MBC2).

    Pellegrini, Christine A; Steglitz, Jeremy; Johnston, Winter; Warnick, Jennifer; Adams, Tiara; McFadden, H G; Siddique, Juned; Hedeker, Donald; Spring, Bonnie

    2015-03-01

    Suboptimal diet and inactive lifestyle are among the most prevalent preventable causes of premature death. Interventions that target multiple behaviors are potentially efficient; however the optimal way to initiate and maintain multiple health behavior changes is unknown. The Make Better Choices 2 (MBC2) trial aims to examine whether sustained healthful diet and activity change are best achieved by targeting diet and activity behaviors simultaneously or sequentially. Study design approximately 250 inactive adults with poor quality diet will be randomized to 3 conditions examining the best way to prescribe healthy diet and activity change. The 3 intervention conditions prescribe: 1) an increase in fruit and vegetable consumption (F/V+), decrease in sedentary leisure screen time (Sed-), and increase in physical activity (PA+) simultaneously (Simultaneous); 2) F/V+ and Sed- first, and then sequentially add PA+ (Sequential); or 3) Stress Management Control that addresses stress, relaxation, and sleep. All participants will receive a smartphone application to self-monitor behaviors and regular coaching calls to help facilitate behavior change during the 9 month intervention. Healthy lifestyle change in fruit/vegetable and saturated fat intakes, sedentary leisure screen time, and physical activity will be assessed at 3, 6, and 9 months. MBC2 is a randomized m-Health intervention examining methods to maximize initiation and maintenance of multiple healthful behavior changes. Results from this trial will provide insight about an optimal technology supported approach to promote improvement in diet and physical activity. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. TOUGH2 software qualification

    Pruess, K.; Simmons, A.; Wu, Y.S.; Moridis, G.

    1996-02-01

    TOUGH2 is a numerical simulation code for multi-dimensional coupled fluid and heat flow of multiphase, multicomponent fluid mixtures in porous and fractured media. It belongs to the MULKOM (open-quotes MULti-KOMponentclose quotes) family of codes and is a more general version of the TOUGH simulator. The MULKOM family of codes was originally developed with a focus on geothermal reservoir simulation. They are suited to modeling systems which contain different fluid mixtures, with applications to flow problems arising in the context of high-level nuclear waste isolation, oil and gas recovery and storage, and groundwater resource protection. TOUGH2 is essentially a subset of MULKOM, consisting of a selection of the better tested and documented MULKOM program modules. The purpose of this package of reports is to provide all software baseline documents necessary for the software qualification of TOUGH2

  11. TOUGH2 software qualification

    Pruess, K.; Simmons, A.; Wu, Y.S.; Moridis, G.

    1996-02-01

    TOUGH2 is a numerical simulation code for multi-dimensional coupled fluid and heat flow of multiphase, multicomponent fluid mixtures in porous and fractured media. It belongs to the MULKOM ({open_quotes}MULti-KOMponent{close_quotes}) family of codes and is a more general version of the TOUGH simulator. The MULKOM family of codes was originally developed with a focus on geothermal reservoir simulation. They are suited to modeling systems which contain different fluid mixtures, with applications to flow problems arising in the context of high-level nuclear waste isolation, oil and gas recovery and storage, and groundwater resource protection. TOUGH2 is essentially a subset of MULKOM, consisting of a selection of the better tested and documented MULKOM program modules. The purpose of this package of reports is to provide all software baseline documents necessary for the software qualification of TOUGH2.

  12. Who Makes the Choice? Rethinking the Role of Autonomy and Relatedness in Chinese Children's Motivation

    Bao, Xue-Hua; Lam, Shui-Fong

    2008-01-01

    The importance of autonomy for children's motivation in collectivistic cultures has been debated hotly. With the understanding that autonomy is not equivalent to freedom of choice, 4 studies addressed this debate by investigating how socioemotional relatedness, choice, and autonomy were related to Chinese children's motivation. Study 1 (N = 56,…

  13. Making Sustainable Energy Choices: Insights on the Energy/Water/Land Nexus

    2014-10-01

    This periodic publication summarizes insights from the body of NREL analysis work. In this issue of Analysis Insights, we examine the implications of our energy choices on water, land use, climate, developmental goals, and other factors. Collectively, NREL's work helps policymakers and investors understand and evaluate energy choices within the complex web of connections, or nexus, between energy, water, and land.

  14. The dynamics of decision making in risky choice: An Eye-tracking Analysis

    Susann eFiedler; Andreas eGlöckner

    2012-01-01

    In the last years, research on risky choice has moved beyond analyzing choices only. Models have been suggested that aim to describe the underlying cognitive processes and some studies have tested process predictions of these models. Prominent approaches are evidence accumulation models such as decision field theory (DFT), simple serial heuristic models such as the adaptive toolbox, and connectionist approaches such as the parallel constraint satisfaction (PCS) model. In two studies involving...

  15. Thermodynamic view on decision-making process: emotions as a potential power vector of realization of the choice.

    Pakhomov, Anton; Sudin, Natalya

    2013-12-01

    This research is devoted to possible mechanisms of decision-making in frames of thermodynamic principles. It is also shown that the decision-making system in reply to emotion includes vector component which seems to be often a necessary condition to transfer system from one state to another. The phases of decision-making system can be described as supposed to be nonequilibrium and irreversible to which thermodynamics laws are applied. The mathematical model of a decision choice, proceeding from principles of the nonlinear dynamics considering instability of movement and bifurcation is offered. The thermodynamic component of decision-making process on the basis of vector transfer of energy induced by emotion at the given time is surveyed. It is proposed a three-modular model of decision making based on principles of thermodynamics. Here it is suggested that at entropy impact due to effect of emotion, on the closed system-the human brain,-initially arises chaos, then after fluctuations of possible alternatives which were going on-reactions of brain zones in reply to external influence, an order is forming and there is choice of alternatives, according to primary entrance conditions and a state of the closed system. Entropy calculation of a choice expectation of negative and positive emotion shows judgment possibility of existence of "the law of emotion conservation" in accordance with several experimental data.

  16. iTOUGH2 Universal Optimization Using the PEST Protocol

    Finsterle, S.A.

    2010-01-01

    iTOUGH2 (http://www-esd.lbl.gov/iTOUGH2) is a computer program for parameter estimation, sensitivity analysis, and uncertainty propagation analysis [Finsterle, 2007a, b, c]. iTOUGH2 contains a number of local and global minimization algorithms for automatic calibration of a model against measured data, or for the solution of other, more general optimization problems (see, for example, Finsterle [2005]). A detailed residual and estimation uncertainty analysis is conducted to assess the inversion results. Moreover, iTOUGH2 can be used to perform a formal sensitivity analysis, or to conduct Monte Carlo simulations for the examination for prediction uncertainties. iTOUGH2's capabilities are continually enhanced. As the name implies, iTOUGH2 is developed for use in conjunction with the TOUGH2 forward simulator for nonisothermal multiphase flow in porous and fractured media [Pruess, 1991]. However, iTOUGH2 provides FORTRAN interfaces for the estimation of user-specified parameters (see subroutine USERPAR) based on user-specified observations (see subroutine USEROBS). These user interfaces can be invoked to add new parameter or observation types to the standard set provided in iTOUGH2. They can also be linked to non-TOUGH2 models, i.e., iTOUGH2 can be used as a universal optimization code, similar to other model-independent, nonlinear parameter estimation packages such as PEST [Doherty, 2008] or UCODE [Poeter and Hill, 1998]. However, to make iTOUGH2's optimization capabilities available for use with an external code, the user is required to write some FORTRAN code that provides the link between the iTOUGH2 parameter vector and the input parameters of the external code, and between the output variables of the external code and the iTOUGH2 observation vector. While allowing for maximum flexibility, the coding requirement of this approach limits its applicability to those users with FORTRAN coding knowledge. To make iTOUGH2 capabilities accessible to many application models

  17. What does the new breed of decision-making methodologies mean for choices and norms in hydrological science?

    Wikman-Svahn, Per

    2013-04-01

    Hydrological sciences are increasingly utilized in decision-making contexts that need to manage deep uncertainty, changing conditions and very long-lead times and lifetimes. Traditional optimizing approaches become problematic in such situations. For example, optimizing approaches may underestimate the importance of low probability outcomes, or very uncertain outcomes. Alternative decision-making strategies are therefore increasingly used in hydrological applications, including "bottom-up/top-down", "context-first", "decision-scaling", "assess risk of policy", "robust", "resilient" or "flexible" approaches. These kinds of strategies are typically designed to handle very uncertain and diverse outcomes, and often start from the particular decision-making context, in contrast to more traditional "predict-then-act" or "science first" approaches. Contemporary research in philosophy of science stress the influence of value judgments and norms in scientific assessments. In particular, this literature points out that implicit anticipated applications often influence choices made in scientific assessments. Furthermore, this literature also emphasize that choices made at within scientific assessments have consequences for decision-making later on. One reason is that it is often difficult for decision-makers to see what choices are made and the implications of these choices. Another reason is that information that could be of use for decision-makers are lost at an early stage. For example, the choice to focus on central estimates and not providing assessments on more unlikely outcomes is a choice that has consequences for what outcomes are taken into account in the decision-making process. This paper develops this argument and then analyzes the implications of these new developments for hydrological science. One implication of the increasing use of the new breed of planning strategies is that a broader range of uncertainty in scientific assessments becomes desirable in order

  18. Physician choice making and characteristics associated with using physician-rating websites: cross-sectional study.

    Emmert, Martin; Meier, Florian; Pisch, Frank; Sander, Uwe

    2013-08-28

    Over the past decade, physician-rating websites have been gaining attention in scientific literature and in the media. However, little knowledge is available about the awareness and the impact of using such sites on health care professionals. It also remains unclear what key predictors are associated with the knowledge and the use of physician-rating websites. To estimate the current level of awareness and use of physician-rating websites in Germany and to determine their impact on physician choice making and the key predictors which are associated with the knowledge and the use of physician-rating websites. This study was designed as a cross-sectional survey. An online panel was consulted in January 2013. A questionnaire was developed containing 28 questions; a pretest was carried out to assess the comprehension of the questionnaire. Several sociodemographic (eg, age, gender, health insurance status, Internet use) and 2 health-related independent variables (ie, health status and health care utilization) were included. Data were analyzed using descriptive statistics, chi-square tests, and t tests. Binary multivariate logistic regression models were performed for elaborating the characteristics of physician-rating website users. Results from the logistic regression are presented for both the observed and weighted sample. In total, 1505 respondents (mean age 43.73 years, SD 14.39; 857/1505, 57.25% female) completed our survey. Of all respondents, 32.09% (483/1505) heard of physician-rating websites and 25.32% (381/1505) already had used a website when searching for a physician. Furthermore, 11.03% (166/1505) had already posted a rating on a physician-rating website. Approximately 65.35% (249/381) consulted a particular physician based on the ratings shown on the websites; in contrast, 52.23% (199/381) had not consulted a particular physician because of the publicly reported ratings. Significantly higher likelihoods for being aware of the websites could be

  19. Physician trainees' decision making and information processing: choice size and Medicare Part D.

    Barnes, Andrew J; Hanoch, Yaniv; Martynenko, Melissa; Wood, Stacey; Rice, Thomas; Federman, Alex D

    2013-01-01

    Many patients expect their doctor to help them choose a Medicare prescription drug plan. Whether the size of the choice set affects clinicians' decision processes and strategy selection, and the quality of their choice, as it does their older patients, is an important question with serious financial consequences. Seventy medical students and internal medicine residents completed a within-subject design using Mouselab, a computer program that allows the information-acquisition process to be examined. We examined highly numerate physician trainees' decision processes, strategy, and their ability to pick the cheapest drug plan-as price was deemed the most important factor in Medicare beneficiaries' plan choice-from either 3 or 9 drug plans. Before adjustment, participants were significantly more likely to identify the lowest cost plan when facing three versus nine choices (67.3% vs. 32.8%, pinformation on each attribute (pdecision strategies focusing on comparing alternate plans across a single attribute (search pattern, pdecision process and strategy, numeracy, and amount of medical training, the odds were 10.75 times higher that trainees would choose the lowest cost Medicare Part D drug plan when facing 3 versus 9 drug plans (pdecision environment are needed and suggest physicians' role in their patients' Part D choices may be most productive when assisting seniors with forecasting their expected medication needs and then referring them to the Medicare website or helpline.

  20. The decision-making capacity of elderly hospitalized patients: validation of a test on their choice of return home.

    Romdhani, Mouna; Abbas, Rachid; Peyneau, Cécile; Koskas, Pierre; Houenou Quenum, Nadège; Galleron, Sandrine; Drunat, Olivier

    2018-03-01

    Elderly hospitalized patients have uncertain or questionable capacity to make decisions about their care. Determining whether an elderly patient possesses decision-making capacity to return at home is a major concern for geriatricians in everyday practice. To construct and internally validate a new tool, the dream of home test (DROM-test), as support for decision making hospitalization discharge destination for the elderly in the acute or sub-acute care setting. The DROM-test consists of 10 questions and 4 vignettes based upon the 4 relevant criteria for decision-making: capacity to understand information, to appreciate and reason about medical risks and to communicate a choice. A prospective observational study was conducted during 6 months in 2 geriatric care units in Bretonneau Hospital (Assistance publique, Hôpitaux de Paris). We compared the patient decision of DROM-test regarding discharge recommendations with those of an Expert committee and of the team in charge of the patient. 102 were included: mean age 83.1 + 6.7 [70; 97], 66.67% females. Principal components analysis revealed four dimensions: choice, understanding, reasoning and understanding. The area under the ROC curve was 0.64 for the choice dimension, 0.59 for the understanding, 0.53 for the reasoning and 0.52 for the apprehension. Only the choice dimension was statistically associated with the decision of the committee of experts (p=0.017). Even though Drom-test has limitations, it provides an objective way to ascertain decision-making capacity for hospitalised elderly patients.

  1. Why women of lower educational attainment struggle to make healthier food choices

    Lawrence, Wendy; Skinner, Chas; Haslam, Cheryl

    2009-01-01

    Women of lower educational attainment are more likely to eat unhealthy diets than women of higher educational attainment. To identify influences on the food choices of women with lower educational attainment, 11 focus groups (eight with women of lower, and three with women of higher educational...... attainment) were held. Using a semi-structured discussion guide, environmental, social, historical and psychological factors known to be associated with food choice were explored. Audio recordings were transcribed verbatim and thematically analysed. Compared to women of higher educational attainment, women...... of lower educational attainment had less control over their families' food choices, less support for attempts to eat healthily, fewer opportunities to observe and learn good food-related practices, more negative affect, more perceived environmental constraints and more ambiguous beliefs about...

  2. Factors Affecting Leaf Selection by Foregut-fermenting Proboscis Monkeys: New Insight from in vitro Digestibility and Toughness of Leaves

    Matsuda, Ikki; Clauss, Marcus; Tuuga, Augustine; Sugau, John; Hanya, Goro; Yumoto, Takakazu; Bernard, Henry; Hummel, Jürgen

    2017-01-01

    Free-living animals must make dietary choices in terms of chemical and physical properties, depending on their digestive physiology and availability of food resources. Here we comprehensively evaluated the dietary choices of proboscis monkeys (Nasalis larvatus) consuming young leaves. We analysed the data for leaf toughness and digestibility measured by an in vitro gas production method, in addition to previously reported data on nutrient composition. Leaf toughness, in general, negatively correlated with the crude protein content, one of the most important nutritional factors affecting food selection by leaf-eating primates. This result suggests that leaf toughness assessed by oral sensation might be a proximate cue for its protein content. We confirmed the importance of the leaf chemical properties in terms of preference shown by N. larvatus; leaves with high protein content and low neutral detergent fibre levels were preferred to those of the common plant species. We also found that these preferred leaves were less tough and more digestible than the alternatives. Our in vitro results also suggested that N. larvatus were little affected by secondary plant compounds. However, the spatial distribution pattern of plant species was the strongest factor explaining the selection of the preferred leaf species. PMID:28211530

  3. Does fertility status influence impulsivity and risk taking in human females? Adaptive influences on intertemporal choice and risky decision making.

    Kaighobadi, Farnaz; Stevens, Jeffrey R

    2013-07-18

    Informed by the research on adaptive decision making in other animal species, this study investigated human females' intertemporal and risky choices across the ovulatory cycle. We tested the hypothesis that at peak fertility, women who are exposed to environments that signal availability of higher quality mates (by viewing images of attractive males), become more impulsive and risk-seeking in economic decision tasks. To test this, we collected intertemporal and risky choice measures before and after exposure to images of either attractive males or neutral landscapes both at peak and low fertility conditions. The results showed an interaction between women's fertility status and image type, such that women at peak fertility viewing images of attractive men chose the smaller, sooner monetary reward option less than women at peak fertility viewing neutral images. Neither fertility status nor image type influenced risky choice. Thus, though exposure to images of men altered intertemporal choices at peak fertility, this occurred in the opposite direction than predicted--i.e., women at peak fertility became less impulsive. Nevertheless, the results of the current study provide evidence for shifts in preferences over the ovulatory cycle and opens future research on economic decision making.

  4. Does Fertility Status Influence Impulsivity and Risk Taking in Human Females? Adaptive Influences on Intertemporal Choice and Risky Decision Making

    Farnaz Kaighobadi

    2013-07-01

    Full Text Available Informed by the research on adaptive decision making in other animal species, this study investigated human females' intertemporal and risky choices across the ovulatory cycle. We tested the hypothesis that at peak fertility, women who are exposed to environments that signal availability of higher quality mates (by viewing images of attractive males, become more impulsive and risk-seeking in economic decision tasks. To test this, we collected intertemporal and risky choice measures before and after exposure to images of either attractive males or neutral landscapes both at peak and low fertility conditions. The results showed an interaction between women's fertility status and image type, such that women at peak fertility viewing images of attractive men chose the smaller, sooner monetary reward option less than women at peak fertility viewing neutral images. Neither fertility status nor image type influenced risky choice. Thus, though exposure to images of men altered intertemporal choices at peak fertility, this occurred in the opposite direction than predicted—i.e., women at peak fertility became less impulsive. Nevertheless, the results of the current study provide evidence for shifts in preferences over the ovulatory cycle and opens future research on economic decision making.

  5. TOUGH User's Guide

    Pruess, K.

    1987-08-01

    This document contains a technical description of the TOUGH computer program, which was developed at Lawrence Berkeley Laboratory for simulating the coupled transport of water, vapor, air and heat in porous and fractured media. The physical processes taken into account in TOUGH are discussed, and the governing equations actually solved by the simulator are stated in full detail. A brief overview is given of the mathematical and numerical methods, and the code architecture. The report provides detailed instructions for preparing input decks. Code applications are illustrated by means of six sample problems

  6. Design Choices in a Compiler Course or How to Make Undergraduates Love Formal Notation

    Schwartzbach, Michael Ignatieff

    2008-01-01

    The undergraduate compiler course offers a unique opportunity to combine many aspects of the Computer Science curriculum. We discuss the many design choices that are available for the instructor and present the current compiler course at the University of Aarhus, the design of which displays at l...

  7. Emotion regulation and risk taking: predicting risky choice in deliberative decision making

    Panno, A.; Lauriola, M.; Figner, B.

    2013-01-01

    Only very recently has research demonstrated that experimentally induced emotion regulation strategies (cognitive reappraisal and expressive suppression) affect risky choice (e.g., Heilman et al., 2010). However, it is unknown whether this effect also operates via habitual use of emotion regulation

  8. Playful Mobility Choices: Motivating informed mobility decision making by applying game mechanics

    A. Millonig

    2014-10-01

    Full Text Available Motivating people to change their mobility behaviour patterns towards more sustainable forms of mobility is one of the major challenges regarding climate change and quality of life. Recently, an increasing amount of attempts to use gamification for triggering such behavioural changes can be observed. However, little is known about the actual impact of using game elements. This contribution describes a concept for systematically analysing the group-specific effects of different game mechanics on mobility decision processes (e.g. mode and route choice. Based on theoretical findings concerning player types and mobility styles we developed a framework for identifying effective game mechanics motivating users to explore mobility alternatives and take more informed and more sustainable mode or route choice decisions. The results will form the basis for implementing game mechanics in mobility information services motivating users to explore unfamiliar but more sustainable mobility options.

  9. Tough by name, tough by nature.

    Baillie, Jonathan

    2015-04-01

    Few beds, one would imagine, could withstand three-quarters of a ton landing on them, but this was the challenge successfully met by a box bed from a furniture manufacturer for challenging behaviour environments, Tough Furniture, when, to reassure a customer that the bed could accommodate 30-stone patients, 13 of the company's staff jumped repeatedly on it to ensure that it would survive intact in a real-world setting. Such testing may seem extreme, but is vital, since much of the company's furniture is destined for environments where patients will abuse, and indeed attempt to destroy, components. As MD David Vesty explained to HEJ editor, Jonathan Baillie, when he visited the company's Shropshire headquarters, it is through manufacturing premium quality cabinet furniture that is both attractive and distinctly non-institutional, but will equally withstand the harshest use, that the company has ensured that its products can live up to the brand name.

  10. When good pigeons make bad decisions: Choice with probabilistic delays and outcomes.

    Pisklak, Jeffrey M; McDevitt, Margaret A; Dunn, Roger M; Spetch, Marcia L

    2015-11-01

    Pigeons chose between an (optimal) alternative that sometimes provided food after a 10-s delay and other times after a 40-s delay and another (suboptimal) alternative that sometimes provided food after 10 s but other times no food after 40 s. When outcomes were not signaled during the delays, pigeons strongly preferred the optimal alternative. When outcomes were signaled, choices of the suboptimal alternative increased and most pigeons preferred the alternative that provided no food after the long delay despite the cost in terms of obtained food. The pattern of results was similar whether the short delays occurred on 25% or 50% of the trials. Shortening the 40-s delay to food sharply reduced suboptimal choices, but shortening the delay to no food had little effect. The results suggest that a signaled delay to no food does not punish responding in probabilistic choice procedures. The findings are discussed in terms of conditioned reinforcement by signals for good news. © Society for the Experimental Analysis of Behavior.

  11. Shared decision making and patient choice for growth hormone therapy: current perspectives

    George B

    2016-06-01

    Full Text Available Belinda George, Vageesh Ayyar Department of Endocrinology, St. John’s Medical College Hospital, Bangalore, Karnataka, India Abstract: Growth hormone has now been available in medical practice for close to 50 years. Its use has provided dramatic results in patients with growth hormone deficiency and it is associated with an overall favorable safety profile. Over the years, the utility of growth hormone has expanded to include treatment for short stature associated with conditions other than growth hormone deficiency, and this situation warrants greater involvement of the child and parents in the shared decision-making process. Shared decision making is in good conformance to the principle of informed consent, and it also improves the compliance and adherence to therapy as the patient fully understands the benefit and safety of the treatment. In the pediatric-care setting, the decision-making interactions usually occur between the health care provider, patient, and parents. The process may range from an autonomous decision-making pattern, where the patient or parents are fully responsible for the decision taken, to the paternalistic decision-making pattern, where the health care provider assumes full responsibility for the decision taken. However, the ideal situation is one where a truly shared decision-making process happens, in which the doctor and patient/parents work together to choose an evidence-based option, in line with the patient’s preferences and wishes. The limited data available on shared decision making with regard to growth hormone replacement, however, is not very encouraging and suggests that the actual involvement of the parents as perceived by them is less than optimal. Introduction of a simple structured model for a shared decision-making process that can be easily incorporated into clinical practice and familiarization of health care providers with the same is essential to improve our shared decision-making practices

  12. The Role of Hypertext in Consumer Decision Making. The Case of Travel Destination Choice

    Raúl Valdez Munoz

    2012-01-01

    Full Text Available Travel is one of the most popular items people tend to be comfortable with purchasing over the Internet. Hypertext is a form of electronic text composed of blocks of words (or images linked electronically by multiple paths, chains, or trails. This study explores the importance of hypertext in the travel destination choice from websites. Results show that hypertext links containing images of destinations, informative texts, and search tools are the three most important features utilized by tourist website browsers. This study aims to offer insights into new areas for further research on tourism websites design, application and evaluation.

  13. Private or salaried practice: how do young general practitioners make their career choice? A qualitative study.

    Kinouani, Shérazade; Boukhors, Gary; Luaces, Baptiste; Durieux, William; Cadwallader, Jean-Sébastien; Aubin-Auger, Isabelle; Gay, Bernard

    2016-09-01

    Young French postgraduates in general practice increasingly prefer salaried practice to private practice in spite of the financial incentives offered by the French government or local communities to encourage the latter. This study aimed to explore the determinants of choice between private or salaried practice among young general practitioners. A qualitative study was conducted in the South West of France. Semi-structured interviews of young general practitioners were audio-recorded until data saturation. Recordings were transcribed and then analyzed according to Grounded Theory by three researchers working independently. Sixteen general practitioners participated in this study. For salaried and private doctors, the main factors governing their choice were occupational factors: working conditions, need of varied scope of practice, quality of the doctor-patient relationship or career flexibility. Other factors such as postgraduate training, having worked as a locum or self-interest were also determining. Young general practitioners all expected a work-life balance. The fee-for-service scheme or home visits may have discouraged young general practitioners from choosing private practice. National health policies should increase the attractiveness of ambulatory general practice by promoting the diversification of modes of remuneration and encouraging the organization of group exercises in multidisciplinary medical homes and community health centers.

  14. The rational choice model in family decision making at the end of life.

    Karasz, Alison; Sacajiu, Galit; Kogan, Misha; Watkins, Liza

    2010-01-01

    Most end-of-life decisions are made by family members. Current ethical guidelines for family decision making are based on a hierarchical model that emphasizes the patient's wishes over his or her best interests. Evidence suggests that the model poorly reflects the strategies and priorities of many families. Researchers observed and recorded 26 decision-making meetings between hospital staff and family members. Semi-structured follow-up interviews were conducted. Transcriptions were analyzed using qualitative techniques. For both staff and families, consideration of a patient's best interests generally took priority over the patient's wishes. Staff generally introduced discussion of the patient's wishes for rhetorical purposes, such as persuasion. Competing moral frameworks, which de-emphasized the salience of patients' autonomy and "right to choose," played a role in family decision making. The priority given to the patients' wishes in the hierarchical model does not reflect the priorities of staff and families in making decisions about end-of-life care.

  15. The Choice Project: Peer Workers Promoting Shared Decision Making at a Youth Mental Health Service.

    Simmons, Magenta Bender; Batchelor, Samantha; Dimopoulos-Bick, Tara; Howe, Deb

    2017-08-01

    In youth mental health services, consumer participation is essential, but few implementation strategies exist to engage young consumers. This project evaluated an intervention implemented in an Australian youth mental health service that utilized peer workers to promote shared decision making via an online tool. All new clients ages 16-25 were invited to participate in this nonrandomized comparative study, which used a historical comparison group (N=80). Intervention participants (N=149) engaged with a peer worker and used the online tool before and during their intake assessment. Pre- and postintake data were collected for both groups; measures included decisional conflict, perceived shared decision making, and satisfaction. A series of paired t tests, analyses of variance, and multiple regressions were conducted to assess differences in scores across intervention and comparison groups and pre- and postintake assessments. Ratings of perceived shared decision making with intake workers were higher in the intervention group than in the comparison group (p=.015). In both groups, decisional conflict scores were significantly lower after the intake assessment (pdecision making and lower decisional conflict were associated with satisfaction (pdecision making reported feeling more involved in their assessment. Feeling involved and having lower decisional conflict after seeing an intake worker were important for client satisfaction. These findings demonstrate the importance of both peer work and shared decision making for promoting optimal outcomes in youth mental health services.

  16. Survival or Mortality: Does Risk Attribute Framing Influence Decision-Making Behavior in a Discrete Choice Experiment?

    Veldwijk, Jorien; Essers, Brigitte A B; Lambooij, Mattijs S; Dirksen, Carmen D; Smit, Henriette A; de Wit, G Ardine

    2016-01-01

    To test how attribute framing in a discrete choice experiment (DCE) affects respondents' decision-making behavior and their preferences. Two versions of a DCE questionnaire containing nine choice tasks were distributed among a representative sample of the Dutch population aged 55 to 65 years. The DCE consisted of four attributes related to the decision regarding participation in genetic screening for colorectal cancer (CRC). The risk attribute included was framed positively as the probability of surviving CRC and negatively as the probability of dying from CRC. Panel mixed-logit models were used to estimate the relative importance of the attributes. The data of the positively and negatively framed DCE were compared on the basis of direct attribute ranking, dominant decision-making behavior, preferences, and importance scores. The majority (56%) of the respondents ranked survival as the most important attribute in the positively framed DCE, whereas only a minority (8%) of the respondents ranked mortality as the most important attribute in the negatively framed DCE. Respondents made dominant choices based on survival significantly more often than based on mortality. The framing of the risk attribute significantly influenced all attribute-level estimates and resulted in different preference structures among respondents in the positively and negatively framed data set. Risk framing affects how respondents value the presented risk. Positive risk framing led to increased dominant decision-making behavior, whereas negative risk framing led to risk-seeking behavior. Attribute framing should have a prominent part in the expert and focus group interviews, and different types of framing should be used in the pilot version of DCEs as well as in actual DCEs to estimate the magnitude of the effect of choosing different types of framing. Copyright © 2016 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

  17. Shared decision making and the concept of equipoise: the competences of involving patients in healthcare choices.

    Elwyn, G; Edwards, A; Kinnersley, P; Grol, R

    2000-11-01

    Involving patients in healthcare decisions makes a potentially significant and enduring difference to healthcare outcomes. One difficulty (among many) is that the 'involvement' of patients in decisions has been left undefined. It is usually conceptualised as 'patient centredness', which is a broad and variably interpreted concept that is difficult to assess using current tools. This paper attempts to gauge general practitioners' (GPs') attitudes to patient involvement in decision making and their views about the contextual factors, competences, and stages required to achieve shared decisions within consultations. To explore and understand what constitutes the appropriate involvement of patients in decision making within consultations, to consider previous theory in this field, and to propose a set of competences (skills) and steps that would enable clinical practitioners (generalists) to undertake 'shared decision making' in their clinical environment. Qualitative study using focus group interviews of key informants. Experienced GPs with educational roles have positive attitudes to the involvement of patients in decisions, provided the process matches the role individuals wish to play. They perceive some clinical problems as being more suited to a cooperative approach to decision making and conceptualised the existence of professional equipoise towards the existence of legitimate treatment options as an important facilitative factor. A sequence of skills was proposed as follows: 1) implicit or explicit involvement of patients in the decision-making process; 2) explore ideas, fears, and expectations of the problem and possible treatments; 3) portrayal of equipoise and options; 4) identify preferred data format and provide tailor-made information; 5) checking process: understanding of information and reactions (e.g. ideas, fears, and expectations of possible options); 6) acceptance of process and decision making role preference; 7) make, discuss or defer decisions; 8

  18. The choice among non-callable bonds and make whole, claw back and otherwise ordinary callable bonds

    Booth, LD; Gounopoulos, D; Skinner, F

    2012-01-01

    This paper seeks to explain determinates of the choice and the pricing of various types of callable and non-callable bonds. We find that the popularity of different types of callable and non-callable bonds is significantly related to the economic environment. In addition, the popularity of claw back bonds appear to be driven by agency considerations, make whole bonds by the debt overhang problem, ordinary callable bonds by the need by banks to deal with interest rate changes and non-callable ...

  19. The Home Identity Idea: How Good Homes Can Urge People to Make Environmentally Friendly Choices

    Paulsen, Karoline

    2017-01-01

    This thesis is a discussion on how we identify with the place we live and how we can make good places to live now and in the future. The idea is that if we feel at home in and identify with the place we live, we want to preserve it and make it better for the future. This can have effect on the environment and the climate. If we build places that are good to live in and the people who live there identify with their home place, they would want to live more sustainably. There is also a discussio...

  20. Uncovering Chemical Thinking in Students' Decision Making: A Fuel-Choice Scenario

    Banks, Gregory; Clinchot, Michael; Cullipher, Steven; Huie, Robert; Lambertz, Jennifer; Lewis, Rebecca; Ngai, Courtney; Sevian, Hannah; Szteinberg, Gabriela; Talanquer, Vicente; Weinrich, Melissa

    2015-01-01

    Making decisions about the production and use of chemical substances is of central importance in many fields. In this study, a research team comprising teachers and educational researchers collaborated in collecting and analyzing cognitive interviews with students from 8th grade through first-year university general chemistry in an effort to map…

  1. Socio-Semiotic Patterns in Digital Meaning-Making: Semiotic Choice as Indicator of Communicative Experience

    Sofkova Hashemi, Sylvana

    2017-01-01

    Access to digital technology in the classroom enables the composition and organization of ideas on screen with a variety of semiotic systems of different modes and media. This study explores patterns of communication and preference of design in digital meaning-making of twelve 7-8 years old students. Meanings were shaped in complex uses and…

  2. Pneumocystis PCR: It Is Time to Make PCR the Test of Choice.

    Doyle, Laura; Vogel, Sherilynn; Procop, Gary W

    2017-01-01

    The testing strategy for Pneumocystis at the Cleveland Clinic changed from toluidine blue staining to polymerase chain reaction (PCR). We studied the differences in positivity rates for these assays and compared each with the detection of Pneumocystis in companion specimens by cytology and surgical pathology. We reviewed the results of all Pneumocystis test orders 1 year before and 1 year after the implementation of a Pneumocystis -specific PCR. We also reviewed the corresponding cytology and surgical pathology results, if performed. Finally, we reviewed the medical records of patients with rare Pneumocystis detected by PCR in an effort to differentiate colonization vs true disease. Toluidine blue staining and surgical pathology had similar sensitivities and negative predictive values, both of which were superior to cytology. There was a >4-fold increase in the annual detection of Pneumocystis by PCR compared with toluidine blue staining (toluidine blue staining: 11/1583 [0.69%] vs PCR: 44/1457 [3.0%]; chi-square P < .001). PCR detected 1 more case than surgical pathology and was far more sensitive than cytology. Chart review demonstrated that the vast majority of patients with rare Pneumocystis detected were immunosuppressed, had radiologic findings supportive of this infection, had no other pathogens detected, and were treated for pneumocystosis by the clinical team. PCR was the most sensitive method for the detection of Pneumocystis and should be considered the diagnostic test of choice. Correlation with clinical and radiologic findings affords discrimination of early true disease from the far rarer instances of colonization.

  3. Academic or community practice? What is driving decision-making and career choices.

    Goudreau, Bernadette J; Hassinger, Taryn E; Hedrick, Traci L; Slingluff, Craig L; Schroen, Anneke T; Dengel, Lynn T

    2018-06-18

    Identifying factors that impact progression of surgery trainees into academic versus non-academic practices may permit tailoring residency experiences to promote academic careers in institutions charged with the training of future surgeon scientists. The aim of this study was to identify factors associated with progression of surgery trainees into academic versus non-academic practice. A survey was distributed to 135 surgeons graduating from the University of Virginia residency program from 1964-2016, a single academic institution. Questions addressed practice type, research productivity, work/life balance, mentorship, and overall sentiment toward research and academic surgery. A 5-point Likert scale measured career satisfaction and influence of factors in practice setting choice. Of the 135 surveys that were electronically distributed, 69 participants responded (response rate: 51%). Of the 54 with known current practice types, 34 (63%) were academic and 20 (37%) non-academic. Academic surgeons reported more publications by the conclusion of surgery training (56% vs 25% with >10 publications, P = .02). More academic surgeons reported >$100,000 in student debt at graduation (44% vs 25%, P productive research experiences, current surgical trainees may be more enthusiastic about a career in academic practice. Copyright © 2018 Elsevier Inc. All rights reserved.

  4. Bringing the patient back in: behavioral decision-making and choice in medical economics.

    Mendoza, Roger Lee

    2018-04-01

    We explore the behavioral methodology and "revolution" in economics through the lens of medical economics. We address two questions: (1) Are mainstream economic assumptions of utility-maximization realistic approximations of people's actual behavior? (2) Do people maximize subjective expected utility, particularly in choosing from among the available options? In doing so, we illustrate-in terms of a hypothetical experimental sample of patients with dry eye diagnosis-why and how utility in pharmacoeconomic assessments might be valued differently by patients when subjective psychological, social, cognitive, and emotional factors are considered. While experimentally-observed or surveyed behavior yields stated (rather than revealed) preferences, behaviorism offers a robust toolset in understanding drug, medical device, and treatment-related decisions compared to the optimizing calculus assumed by mainstream economists. It might also do so more perilously than economists have previously understood, in light of the intractable uncertainties, information asymmetries, insulated third-party agents, entry barriers, and externalities that characterize healthcare. Behavioral work has been carried out in many sub-fields of economics. Only recently has it been extended to healthcare. This offers medical economists both the challenge and opportunity of balancing efficiency presumptions with relatively autonomous patient choices, notwithstanding their predictable, yet seemingly consistent, irrationality. Despite its comparative youth and limitations, the scientific contributions of behaviorism are secure and its future in medical economics appears to be promising.

  5. Risk preferences in strategic wildfire decision making: a choice experiment with U.S. wildfire managers.

    Wibbenmeyer, Matthew J; Hand, Michael S; Calkin, David E; Venn, Tyron J; Thompson, Matthew P

    2013-06-01

    Federal policy has embraced risa management as an appropriate paradigm for wildfire management. Economic theory suggests that over repeated wildfire events, potential economic costs and risas of ecological damage are optimally balanced when management decisions are free from biases, risa aversion, and risa seeking. Of primary concern in this article is how managers respond to wildfire risa, including the potential effect of wildfires (on ecological values, structures, and safety) and the likelihood of different fire outcomes. We use responses to a choice experiment questionnaire of U.S. federal wildfire managers to measure attitudes toward several components of wildfire risa and to test whether observed risa attitudes are consistent with the efficient allocation of wildfire suppression resources. Our results indicate that fire managers' decisions are consistent with nonexpected utility theories of decisions under risa. Managers may overallocate firefighting resources when the likelihood or potential magnitude of damage from fires is low, and sensitivity to changes in the probability of fire outcomes depends on whether probabilities are close to one or zero and the magnitude of the potential harm. © 2012 Society for Risk Analysis.

  6. International Higher Education for Whom? Expatriate Students, Choice-Making and International (Im)mobility in the Northern United Arab Emirates

    Rensimer, Lee

    2016-01-01

    This article identifies a research gap on expatriate students attending international branch campuses in their country of residence, and presents evidence that they are insufficiently distinguished from international students in research on student mobility and choice-making. It finds that the priorities and enrollment choices of expatriates are…

  7. Quantum paradox of choice: More freedom makes summoning a quantum state harder

    Adlam, Emily; Kent, Adrian

    2016-06-01

    The properties of quantum information in space-time can be investigated by studying operational tasks, such as "summoning," in which an unknown quantum state is supplied at one point and a call is made at another for it to be returned at a third. Hayden and May [arXiv:1210.0913] recently proved necessary and sufficient conditions for guaranteeing successful return of a summoned state for finite sets of call and return points when there is a guarantee of at most one summons. We prove necessary and sufficient conditions when there may be several possible summonses and complying with any one constitutes success, and we demonstrate the existence of an apparent paradox: The extra freedom makes it strictly harder to complete the summoning task. This result has practical applications for distributed quantum computing and cryptography and implications for our understanding of relativistic quantum information and its localization in space-time.

  8. Context influences decision-making in boys with attention-deficit/hyperactivity disorder: A comparison of traditional and novel choice-impulsivity paradigms.

    Patros, Connor H G; Alderson, R Matt; Lea, Sarah E; Tarle, Stephanie J

    2017-02-01

    Attention-deficit/hyperactivity disorder (ADHD) is characterized by an impaired ability to maintain attention and/or hyperactivity/impulsivity. Impulsivity is frequently defined as the preference for small, immediate rewards over larger, delayed rewards, and has been associated with a variety of negative outcomes such as risky behavior and academic difficulty. Extant studies have uniformly utilized the traditional paradigm of presenting two response choices, which limits the generalization of findings to scenarios in which children/adolescents are faced with dichotomous decisions. The current study is the first to examine the effect of manipulating the number of available response options on impulsive decision-making in boys with and without ADHD. A total of 39 boys (ADHD = 16, typically developing [TD] = 23) aged 8-12 years completed a traditional two-choice impulsivity task and a novel five-choice impulsivity task to examine the effect of manipulating the number of choice responses (two vs five) on impulsive decision-making. A five-choice task was utilized as it presents a more continuous array of choice options when compared to the typical two-choice task, and is comparable given its methodological similarity to the two-choice task. Results suggested that boys with ADHD were significantly more impulsive than TD boys during the two-choice task, but not during the five-choice task. Collectively, these findings suggest that ADHD-related impulsivity is not ubiquitous, but rather dependent on variation in demands and/or context. Further, these findings highlight the importance of examining ADHD-related decision-making within the context of alternative paradigms, as the exclusive utilization of two-choice tasks may promote inaccurate conceptualizations of the disorder.

  9. What Sways People's Judgment of Sleep Quality? A Quantitative Choice-Making Study With Good and Poor Sleepers.

    Ramlee, Fatanah; Sanborn, Adam N; Tang, Nicole K Y

    2017-07-01

    We conceptualized sleep quality judgment as a decision-making process and examined the relative importance of 17 parameters of sleep quality using a choice-based conjoint analysis. One hundred participants (50 good sleepers; 50 poor sleepers) were asked to choose between 2 written scenarios to answer 1 of 2 questions: "Which describes a better (or worse) night of sleep?". Each scenario described a self-reported experience of sleep, stringing together 17 possible determinants of sleep quality that occur at different times of the day (day before, pre-sleep, during sleep, upon waking, day after). Each participant answered 48 questions. Logistic regression models were fit to their choice data. Eleven of the 17 sleep quality parameters had a significant impact on the participants' choices. The top 3 determinants of sleep quality were: Total sleep time, feeling refreshed (upon waking), and mood (day after). Sleep quality judgments were most influenced by factors that occur during sleep, followed by feelings and activities upon waking and the day after. There was a significant interaction between wake after sleep onset and feeling refreshed (upon waking) and between feeling refreshed (upon waking) and question type (better or worse night of sleep). Type of sleeper (good vs poor sleepers) did not significantly influence the judgments. Sleep quality judgments appear to be determined by not only what happened during sleep, but also what happened after the sleep period. Interventions that improve mood and functioning during the day may inadvertently also improve people's self-reported evaluation of sleep quality. © Sleep Research Society 2017. Published by Oxford University Press [on behalf of the Sleep Research Society].

  10. Do dogs (Canis lupus familiaris) make counterproductive choices because they are sensitive to human ostensive cues?

    Marshall-Pescini, Sarah; Passalacqua, Chiara; Miletto Petrazzini, Maria Elena; Valsecchi, Paola; Prato-Previde, Emanuela

    2012-01-01

    Dogs appear to be sensitive to human ostensive communicative cues in a variety of situations, however there is still a measure of controversy as to the way in which these cues influence human-dog interactions. There is evidence for instance that dogs can be led into making evaluation errors in a quantity discrimination task, for example losing their preference for a larger food quantity if a human shows a preference for a smaller one, yet there is, so far, no explanation for this phenomenon. Using a modified version of this task, in the current study we investigated whether non-social, social or communicative cues (alone or in combination) cause dogs to go against their preference for the larger food quantity. Results show that dogs' evaluation errors are indeed caused by a social bias, but, somewhat contrary to previous studies, they highlight the potent effect of stimulus enhancement (handling the target) in influencing the dogs' response. A mild influence on the dog's behaviour was found only when different ostensive cues (and no handling of the target) were used in combination, suggesting their cumulative effect. The discussion addresses possible motives for discrepancies with previous studies suggesting that both the intentionality and the directionality of the action may be important in causing dogs' social biases.

  11. A Shared Decision-Making System for Diabetes Medication Choice Utilizing Electronic Health Record Data.

    Wang, Yu; Li, Peng-Fei; Tian, Yu; Ren, Jing-Jing; Li, Jing-Song

    2017-09-01

    The use of a shared decision-making (SDM) process in antihyperglycemic medication strategy decisions is necessary due to the complexity of the conditions of diabetes patients. Knowledge of guidelines is used as decision aids in clinical situations, and during this process, no patient health conditions are considered. In this paper, we propose an SDM system framework for type-2 diabetes mellitus (T2DM) patients that not only contains knowledge abstracted from guidelines but also employs a multilabel classification model that uses class-imbalanced electronic health record (EHR) data and that aims to provide a recommended list of available antihyperglycemic medications to help physicians and patients have an SDM conversation. The use of EHR data to serve as a decision-support component in decision aids helps physicians and patients to reach a more intuitive understanding of current health conditions and allows the tailoring of the available knowledge to each patient, leading to a more effective SDM. Real-world data from 2542 T2DM inpatient EHRs were substituted by 77 features and eight output labels, i.e., eight antihyperglycemic medications, and these data were utilized to build and validate the recommendation model. The multilabel recommendation model exhibited stable performance in every single-label classification and showed the ability to predict minority positive cases in which the average recall value of the eight classes was 0.9898. As a whole multilabel classifier, the recommendation model demonstrated outstanding performance, with scores of 0.0941 for Hamming Loss, 0.7611 for Accuracy exam , 0.9664 for Recall exam , and 0.8269 for F exam .

  12. Reversible inactivation of the lateral hypothalamus reversed high reward choices in cost-benefit decision-making in rats.

    Karimi, Sara; Mesdaghinia, Azam; Farzinpour, Zahra; Hamidi, Gholamali; Haghparast, Abbas

    2017-11-01

    The Lateral hypothalamus (LH) is an important component of the networks underlying the control of feeding and other motivated behaviors. Cost-benefit decision-making is mediated largely by the prefrontal cortex (PFC) which strongly innervates the LH. Therefore, in the current study, we conducted a series of experiments to elucidate the role of the perifornical area of the lateral hypothalamus (PeF-LH) in effort and/or delay-based decision-making. We trained different groups of rats in a delay-based and/or an effort-based form of cost-benefit T-maze decision- making task in which they could either choose to pay the cost to obtain a high reward in one arm or could obtain a low reward in the other arm with no cost. During test days, the rats received local injections of either vehicle or lidocaine4% (0.5 μl/side), in the PeF-LH. In an effort-based decision task, PeF-LH inactivation led to decrease in high reward choice. Similarly, in a delay-based decision task animals' preference changed to a low but immediately available reward. This was not caused by a spatial memory or motor deficit. PeF-LH inactivation modified decision behavior. The results imply that PeF-LH is important for allowing the animal to pay a cost to acquire greater rewards. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Everyday and medical life choices: decision-making among 8- to 15-year-old school students.

    Alderson, P

    1992-01-01

    How much do young patients expect to be involved in medical decisions affecting them? We are investigating this question during interviews with 8- to 15-year-olds having orthopaedic surgery. Many youngsters taking part in our research project on consent to surgery are more than usually dependent on their parents. We wondered how their views would compare with those of their peers at school. This paper reports a schools survey carried out as a background to the research with young people in hospital. Students in seven schools answered questionnaires on choices about late-night television viewing, new friends, timing homework, seeing their family doctor and consenting to surgery. They were asked about agreement with their parents, how they negotiate disagreement, and when they think they were/will be old enough to make everyday and medical decisions without their parents' help.

  14. Risky decision making across three arenas of choice: are younger and older adults differently susceptible to framing effects?

    Rönnlund, Michael; Karlsson, Erik; Laggnäs, Erica; Larsson, Lisa; Lindström, Therese

    2005-01-01

    In the present study, the authors investigated the effects of framing of options on risky decision making in groups of younger adults (M = 23.8 years, n = 192) and older adults (M = 69.1 years, n = 192). The participants were assigned to one of three scenarios varying in the goods at stake (human lives, paintings, money). The authors observed a majority preference in favor of the risky options after negative, but not positive framing. They also found, as they had predicted, that the type of framing effect varied across scenarios, with a bidirectional framing effect for the life-death scenario and unidirectional (risk averse) framing effects when public property (paintings) or personal property (money) were at stake. It is important to note that these choice preference patterns were highly similar across the age groups, which reinforced the conclusion that younger and older adults are equally susceptible to framing effects.

  15. Making choice between competing rewards in uncertain versus safe social environment:role of neuronal nicotinic receptors of acetylcholine

    Jonathan eChabout

    2013-08-01

    Full Text Available In social environments, choosing between multiple rewards is modulated by the uncertainty of the situation. Here, we compared how mice interact with a conspecific and how they use acoustic communication during this interaction in a 3 chambers task (no social threat was possible and a Social Interaction Task, SIT (uncertain situation as two mice interact freely. We further manipulated the motivational state of the mice to see how they rank natural rewards such as social contact, food, and novelty seeking. We previously showed that beta2-subunit containing nicotinic receptors -2*nAChRs- are required for establishing reward ranking between social interaction, novelty exploration, and food consumption in social situations with high uncertainty. Knockout mice for 2*nAChRs -2-/-mice- exhibit profound impairment in making social flexible choices, as compared to control -WT- mice.Our current data shows that being confronted with a conspecific in a socially safe environment as compared to a more uncertain environment, drastically reduced communication between the two mice, and changed their way to deal with a social conspecific. Furthermore, we demonstrated for the first time, that 2-/- mice had the same motivational ranking than WT mice when placed in a socially safe environment. Therefore,2*nAChRs are not necessary for integrating social information or social rewards per se, but are important for making choices, only in a socially uncertain environment.This seems particularly important in the context of Social Neuroscience, as numerous animal models are used to provide novel insights and to test promising novel treatments of human pathologies affecting social and communication processes, among which Autistic spectrum disorders and schizophrenia.

  16. Single-larger-portion-size and dual-column nutrition labeling may help consumers make more healthful food choices.

    Lando, Amy M; Lo, Serena C

    2013-02-01

    The Food and Drug Administration is considering changes to the Nutrition Facts label to help consumers make more healthful choices. To examine the effects of modifications to the Nutrition Facts label on foods that can be listed as having 1 or 2 servings per container, but are reasonably consumed at a single eating occasion. Participants were randomly assigned to study conditions that varied on label format, product, and nutrition profile. Data were collected via an online consumer panel. Adults aged 18 years and older were recruited from Synovate's online household panel. Data were collected during August 2011. A total of 32,897 invitations were sent for a final sample of 9,493 interviews. Participants were randomly assigned to one of 10 label formats classified into three groups: listing 2 servings per container with a single column, listing 2 servings per container with a dual column, and listing a single serving per container. Within these groups there were versions that enlarged the font size for "calories," removed "calories from fat," and changed the wording for serving size declaration. The single product task measured product healthfulness, the amount of calories and various nutrients per serving and per container, and label perceptions. The product comparison task measured ability to identify the healthier product and the product with fewer calories per container and per serving. Analysis of covariance models with Tukey-Kramer tests were used. Covariates included general label use, age, sex, level of education, and race/ethnicity. Single-serving and dual-column formats performed better and scored higher on most outcome measures. For products that contain 2 servings but are customarily consumed at a single eating occasion, using a single-serving or dual-column labeling approach may help consumers make healthier food choices. Published by Elsevier Inc.

  17. Towards a life cycle sustainability assessment: making informed choices on products

    Ciroth, Andreas [GreenDeltaTC, Berlin (Germany); Finkbeiner, Matthias; Traverso, Marzia [TU Berlin (Germany); Hildenbrand, Jutta [Chalmers University (United States); Kloepffer, Walter [Editor-in-Chief of the International Journal of Life Cycle Assessment (Germany); Mazijn, Bernard [Ghent University (Belgium); Prakash, Siddharth [Oeko-Institut (Germany); Sonnemann, Guido; Valdivia, Sonia [UNEP (France); Ugaya, Cassia Maria Lie [Technological Federal University of Parana, ACV (Brazil); Vickery-Niederman, Gina [University of Arkansas (United States)

    2011-07-01

    In this introduction to the concept of life cycle sustainability assessment (LCSA), we acknowledge the foundations laid by previous works and initiatives. One such initiative has been the ISO 14040 series (Environmental management -- Life cycle assessment -- Principles and framework), which in addition to the ISO 26000: Social Responsibility Guidance Standard, and the contribution of a number of international initiatives (Appendix A) have been essential for the development of this publication. The life cycle of a product involves flows of material, energy and money. Nonetheless, the picture is not complete unless we look also at the production and consumption impacts on all actors along the 'value chain' -- workers, local communities, consumers and society itself. Different life cycle assessment techniques allow individuals and enterprises to assess the impact of their purchasing decisions and production methods along different aspects of this value chain. An (Environmental) life cycle assessment (LCA) looks at potential impacts to the environment as a result of the extraction of resources, transportation, production, use, recycling and discarding of products; life cycle costing (LCC) is used to assess the cost implications of this life cycle; and social life cycle assessment (S-LCA) examines the social consequences. However, in order to get the 'whole picture', it is vital to extend current life cycle thinking to encompass all three pillars of sustainability: (i) environmental, (ii) economic and (iii) social. This means carrying out an assessment based on environmental, economic and social issues -- by conducting an overarching life cycle sustainability assessment (LCSA). This publication shows how all three techniques -- which all share similar methodological frameworks and aims -- can be combined to make the move towards an overarching LCSA possible. Because it is holistic, systemic and rigorous, (environmental) LCA is the preferred technique

  18. Towards a life cycle sustainability assessment: making informed choices on products

    Ciroth, Andreas [GreenDeltaTC, Berlin (Germany); Finkbeiner, Matthias; Traverso, Marzia [TU Berlin (Germany); Hildenbrand, Jutta [Chalmers University (United States); Kloepffer, Walter [Editor-in-Chief of the International Journal of Life Cycle Assessment (Germany); Mazijn, Bernard [Ghent University (Belgium); Prakash, Siddharth [Oeko-Institut (Germany); Sonnemann, Guido; Valdivia, Sonia [UNEP (France); Ugaya, Cassia Maria Lie [Technological Federal University of Parana, ACV (Brazil); Vickery-Niederman, Gina [University of Arkansas (United States)

    2011-07-01

    In this introduction to the concept of life cycle sustainability assessment (LCSA), we acknowledge the foundations laid by previous works and initiatives. One such initiative has been the ISO 14040 series (Environmental management -- Life cycle assessment -- Principles and framework), which in addition to the ISO 26000: Social Responsibility Guidance Standard, and the contribution of a number of international initiatives (Appendix A) have been essential for the development of this publication. The life cycle of a product involves flows of material, energy and money. Nonetheless, the picture is not complete unless we look also at the production and consumption impacts on all actors along the 'value chain' -- workers, local communities, consumers and society itself. Different life cycle assessment techniques allow individuals and enterprises to assess the impact of their purchasing decisions and production methods along different aspects of this value chain. An (Environmental) life cycle assessment (LCA) looks at potential impacts to the environment as a result of the extraction of resources, transportation, production, use, recycling and discarding of products; life cycle costing (LCC) is used to assess the cost implications of this life cycle; and social life cycle assessment (S-LCA) examines the social consequences. However, in order to get the 'whole picture', it is vital to extend current life cycle thinking to encompass all three pillars of sustainability: (i) environmental, (ii) economic and (iii) social. This means carrying out an assessment based on environmental, economic and social issues -- by conducting an overarching life cycle sustainability assessment (LCSA). This publication shows how all three techniques -- which all share similar methodological frameworks and aims -- can be combined to make the move towards an overarching LCSA possible. Because it is holistic, systemic and rigorous, (environmental) LCA is the preferred technique when it comes to

  19. Use of food labels by adolescents to make healthier choices on snacks: a cross-sectional study from Sri Lanka.

    Talagala, Ishanka A; Arambepola, Carukshi

    2016-08-08

    Unhealthy snacking is commonly seen among adolescents. Therefore, use of food labels is promoted for making healthier choices on packaged snacks. This study was conducted to assess the use of food labels in making choices on packaged snack and its associated factors among adolescents. A cross-sectional study was conducted in 2012 among 542 Grade 12 students in Sri Lanka. Eight classes were selected as 'clusters' for the study (two classes each from two schools that were selected randomly from each list of 'Girls only' and 'Boys only' schools in Colombo district). A self-administered questionnaire assessed their socio-demography, snacking behaviour, attitudes and nutrition knowledge related to food labels. Adolescents' use of labels was assessed by three practices (label reading frequency, attention paid to label contents and correct interpretation of six hypothetical labels of snacks). Based on total scores obtained for the three practices, 'satisfactory' (score ≥75(th) percentile mark) and 'unsatisfactory' (score pocket money at least once/week on packaged snacks; predominantly on biscuits (85 %) and cola-drinks (77 %) and 88 % selected snacks on their own. The majority (74.5 %) was frequent ('always' or 'most often') label readers with female predominance (p < 0.05). Over 74 % paid attention frequently to the brand name (75 %), price (85 %) and nutrition panel (81 %). Over 64 % were able to select the better food label when given a choice between two snacks, although some did it for reasons such as attractive label (63 %). The majority (84 %) had good knowledge (obtaining more than the 75(th) percentile mark) on interpreting labels. Although not statistically significant, 'unsatisfactory' label use was higher among males (73 %), purchasing power (70.4 %) and unhealthy snacking behaviour (73 %). In contrast, among the marketing strategies, identifying known brands (73.2 %) and imported products (75.8 %) as 'good' products were significantly

  20. Use of food labels by adolescents to make healthier choices on snacks: a cross-sectional study from Sri Lanka

    Ishanka A. Talagala

    2016-08-01

    Full Text Available Abstract Background Unhealthy snacking is commonly seen among adolescents. Therefore, use of food labels is promoted for making healthier choices on packaged snacks. This study was conducted to assess the use of food labels in making choices on packaged snack and its associated factors among adolescents. Methods A cross–sectional study was conducted in 2012 among 542 Grade 12 students in Sri Lanka. Eight classes were selected as ‘clusters’ for the study (two classes each from two schools that were selected randomly from each list of ‘Girls only’ and ‘Boys only’ schools in Colombo district. A self-administered questionnaire assessed their socio-demography, snacking behaviour, attitudes and nutrition knowledge related to food labels. Adolescents’ use of labels was assessed by three practices (label reading frequency, attention paid to label contents and correct interpretation of six hypothetical labels of snacks. Based on total scores obtained for the three practices, ‘satisfactory’ (score ≥75th percentile mark and ‘unsatisfactory’ (score <75th percentile mark label users were identified. Using SPSS, associations were assessed at 0.05 significance level using Chi-square-test. Results Of the participants, 51 % were males; 61 % spent their pocket money at least once/week on packaged snacks; predominantly on biscuits (85 % and cola-drinks (77 % and 88 % selected snacks on their own. The majority (74.5 % was frequent (‘always’ or ‘most often’ label readers with female predominance (p < 0.05. Over 74 % paid attention frequently to the brand name (75 %, price (85 % and nutrition panel (81 %. Over 64 % were able to select the better food label when given a choice between two snacks, although some did it for reasons such as attractive label (63 %. The majority (84 % had good knowledge (obtaining more than the 75th percentile mark on interpreting labels. Although not statistically significant,

  1. Governance mode vs. governance fit? : Performance implications of make-or-ally choices for product innovation in the worldwide aircraft industry, 1942-2000

    Castaner, X.; Mulotte, L.; Garrette, B.; Dussauge, P.

    We examine the impact of governance mode and governance fit on performance in make-or-ally decisions. We argue that while horizontal collaboration and autonomous governance have direct and countervailing performance implications, the alignment of make-or-ally choices with the focal firm's resource

  2. The Environment Makes a Difference: The Impact of Explicit and Implicit Attitudes as Precursors in Different Food Choice Tasks.

    König, Laura M; Giese, Helge; Schupp, Harald T; Renner, Britta

    2016-01-01

    Studies show that implicit and explicit attitudes influence food choice. However, precursors of food choice often are investigated using tasks offering a very limited number of options despite the comparably complex environment surrounding real life food choice. In the present study, we investigated how the assortment impacts the relationship between implicit and explicit attitudes and food choice (confectionery and fruit), assuming that a more complex choice architecture is more taxing on cognitive resources. Specifically, a binary and a multiple option choice task based on the same stimulus set (fake food items) were presented to ninety-seven participants. Path modeling revealed that both explicit and implicit attitudes were associated with relative food choice (confectionery vs. fruit) in both tasks. In the binary option choice task, both explicit and implicit attitudes were significant precursors of food choice, with explicit attitudes having a greater impact. Conversely, in the multiple option choice task, the additive impact of explicit and implicit attitudes was qualified by an interaction indicating that, even if explicit and implicit attitudes toward confectionery were inconsistent, more confectionery was chosen than fruit if either was positive. This compensatory 'one is sufficient'-effect indicates that the structure of the choice environment modulates the relationship between attitudes and choice. The study highlights that environmental constraints, such as the number of choice options, are an important boundary condition that need to be included when investigating the relationship between psychological precursors and behavior.

  3. Making the EZ Choice

    2001-01-01

    Analytical Mechanics Associates, Inc. (AMA), of Hampton, Virginia, created the EZopt software application through Small Business Innovation Research (SBIR) funding from NASA's Langley Research Center. The new software is a user-friendly tool kit that provides quick and logical solutions to complex optimal control problems. In its most basic form, EZopt converts process data into math equations and then proceeds to utilize those equations to solve problems within control systems. EZopt successfully proved its advantage when applied to short-term mission planning and onboard flight computer implementation. The technology has also solved multiple real-life engineering problems faced in numerous commercial operations. For instance, mechanical engineers use EZopt to solve control problems with robots, while chemical plants implement the application to overcome situations with batch reactors and temperature control. In the emerging field of commercial aerospace, EZopt is able to optimize trajectories for launch vehicles and perform potential space station- keeping tasks. Furthermore, the software also helps control electromagnetic devices in the automotive industry.

  4. Making Choices about Change.

    Steinburg, Craig; And Others

    1992-01-01

    This special report includes four articles arising from the American Society for Training and Development's symposium, "Approaches to Change in Organizations": "Taking Charge of of Change" (Steinburg); "Five Views of Change" (Conner et al.); "Breakpoint Change" (Land, Jarman); and "Approaches to Change" (Kotler). (JOW)

  5. Parents' accounts : factors considered when deciding how far to involve their son/daughter with learning disabilities in choice-making

    Mitchell, Wendy Ann

    2012-01-01

    There is limited literature on the processes of choice-making in families of young people with learning disabilities. This paper examines the factors considered by parents of young people with learning disabilities when deciding their own and their child's role in a range of significant choices (health, social care and education) about their child's life. The paper reports data collected from a sub-sample of 14 parents recruited from 11 families participating in a longitudinal (2007-2010) qua...

  6. Tough Times: Strategic Planning as a War Canoe

    Seymour, Daniel

    2011-01-01

    In this article, the author discusses how to make strategic planning a more valuable tool for higher education in today's tough times. Strategic planning is really the answer to five straightforward questions. The first three represent the plan itself, while the last two are what makes the plan vital and dynamic: (1) Why do we exist?; (2) What do…

  7. The toughness of split graphs

    Woeginger, G.J.

    1998-01-01

    In this short note we argue that the toughness of split graphs can be computed in polynomial time. This solves an open problem from a recent paper by Kratsch et al. (Discrete Math. 150 (1996) 231–245).

  8. Can Food Stamps Do More to Improve Food Choices? An Economic Perspective--Making Healthy Food Choices Easier: Ideas From Behavioral Economics

    Mancino, Lisa; Andrews, Margaret S.

    2007-01-01

    With obesity the most prevalent nutrition problem facing Americans at all economic levels, promoting diets that provide adequate nutrition without too many calories has become an important objective for the Food Stamp Program. Findings from behavioral economics suggest innovative, low-cost ways to improve the diet quality of food stamp participants without restricting their freedom of choice. Unlike more traditional economic interventions, such as changing prices or banning specific foods, th...

  9. How to make rural jobs more attractive to health workers. Findings from a discrete choice experiment in Tanzania.

    Kolstad, Julie Riise

    2011-02-01

    The geographical imbalance of the health workforce in Tanzania represents a serious problem when it comes to delivering crucial health services to a large share of the population. This study provides new quantitative information about how to make jobs in rural areas more attractive to newly educated clinical officers (COs). A unique data set stemming from a discrete choice experiment with CO finalists in Tanzania is applied. The results show that offering continuing education after a certain period of service is one of the most powerful recruitment instruments the authorities have available. Increased salaries and hardship allowances will also substantially increase recruitment in rural areas. Offers of decent housing and good infrastructure, including the provision of equipment, will increase recruitment to rural remote areas but not as much as higher wages and offers of education. Women are less responsive to pecuniary incentives and are more concerned with factors that directly allow them to do a good job, while those with parents living in a remote rural area are generally less responsive to the proposed policies. When the willingness to help other people is a strong motivating force, policies that improve the conditions for helping people appear particularly effective.

  10. Governance mode vs. governance fit? : Performance implications of make-or-ally choices for product innovation in the worldwide aircraft industry, 1942-2000

    Castaner, X.; Mulotte, L.; Garrette, B.; Dussauge, P.

    2014-01-01

    We examine the impact of governance mode and governance fit on performance in make-or-ally decisions. We argue that while horizontal collaboration and autonomous governance have direct and countervailing performance implications, the alignment of make-or-ally choices with the focal firm's resource endowment and the activity's resource requirements leads to better performance. Data on the aircraft industry show that relative to aircraft developed autonomously, collaborative aircraft exhibit gr...

  11. New unified fracture toughness estimation scheme for structural integrity assessment

    Wallin, K.; Nevasmaa, P. [VTT, Espoo (Finland); Bannister, A. [Research and Development, British Steel plc., Swinden Technology Centre Rotherham (United Kingdom)

    1998-12-31

    At present, treatment of fracture toughness data varies depending on the type of data (K{sub IC}, J, CTOD) that are available for fracture mechanics analysis. This complicates structural integrity assessment and makes it difficult to apply any single, unified procedure. Within the Brite-Euram project `SINTAP` a fracture toughness estimation scheme has been developed for the unified treatment of data for use in structural integrity assessment. As a procedure, it can be applied to Charpy data, as well as to fracture toughness data, and is suitable for the treatment of data at both single and different temperatures. The data sets may contain results from both homogeneous and inhomogeneous material, making the procedure applicable also to welded joints. The procedure allows fracture toughness assessment with quantified probability and confidence levels. Irrespective of the type of the original data, one material-specific K{sub mat} value representing a conservative estimate of the mean fracture toughness is obtained (with its probability distribution). This information can then be applied to structural integrity assessment. (orig.) 4 refs.

  12. New unified fracture toughness estimation scheme for structural integrity assessment

    Wallin, K; Nevasmaa, P [VTT, Espoo (Finland); Bannister, A [Research and Development, British Steel plc., Swinden Technology Centre Rotherham (United Kingdom)

    1999-12-31

    At present, treatment of fracture toughness data varies depending on the type of data (K{sub IC}, J, CTOD) that are available for fracture mechanics analysis. This complicates structural integrity assessment and makes it difficult to apply any single, unified procedure. Within the Brite-Euram project `SINTAP` a fracture toughness estimation scheme has been developed for the unified treatment of data for use in structural integrity assessment. As a procedure, it can be applied to Charpy data, as well as to fracture toughness data, and is suitable for the treatment of data at both single and different temperatures. The data sets may contain results from both homogeneous and inhomogeneous material, making the procedure applicable also to welded joints. The procedure allows fracture toughness assessment with quantified probability and confidence levels. Irrespective of the type of the original data, one material-specific K{sub mat} value representing a conservative estimate of the mean fracture toughness is obtained (with its probability distribution). This information can then be applied to structural integrity assessment. (orig.) 4 refs.

  13. Fracture toughness of irradiated beryllium

    Beeston, J.M.

    1978-01-01

    The fracture toughness of nuclear grade hot-pressed beryllium upon irradiation to fluences of 3.5 to 5.0 x 10 21 n/cm 2 , E greater than 1 MeV, was determined. Procedures and data relating to a round-robin test contributing to a standard ASTM method for unirradiated beryllium are discussed in connection with the testing of irradiated specimens. A porous grade of beryllium was also irradiated and tested, thereby enabling some discrimination between the models for describing the fracture toughness behavior of porous beryllium. The fracture toughness of unirradiated 2 percent BeO nuclear grade beryllium was 12.0 MPa m/sup 1 / 2 /, which was reduced 60 percent upon irradiation at 339 K and testing at 295 K. The fracture toughness of a porous grade of beryllium was 13.1 MPa m/sup 1 / 2 /, which was reduced 68 percent upon irradiation and testing at the same conditions. Reasons for the reduction in fracture toughness upon irradiation are discussed

  14. Valence of emotions and moral decision-making: increased pleasantness to pleasant images and decreased unpleasantness to unpleasant images are associated with utilitarian choices in healthy adults.

    Carmona-Perera, Martina; Martí-García, Celia; Pérez-García, Miguel; Verdejo-García, Antonio

    2013-01-01

    Moral decision-making is a key asset for humans' integration in social contexts, and the way we decide about moral issues seems to be strongly influenced by emotions. For example, individuals with deficits in emotional processing tend to deliver more utilitarian choices (accepting an emotionally aversive action in favor of communitarian well-being). However, little is known about the association between emotional experience and moral-related patterns of choice. We investigated whether subjective reactivity to emotional stimuli, in terms of valence, arousal, and dominance, is associated with moral decision-making in 95 healthy adults. They answered to a set of moral and non-moral dilemmas and assessed emotional experience in valence, arousal and dominance dimensions in response to neutral, pleasant, unpleasant non-moral, and unpleasant moral pictures. Results showed significant correlations between less unpleasantness to negative stimuli, more pleasantness to positive stimuli and higher proportion of utilitarian choices. We also found a positive association between higher arousal ratings to negative moral laden pictures and more utilitarian choices. Low dominance was associated with greater perceived difficulty over moral judgment. These behavioral results are in fitting with the proposed role of emotional experience in moral choice.

  15. Valence of emotions and moral decision-making: increased pleasantness to pleasant images and decreased unpleasantness to unpleasant images are associated with utilitarian choices in healthy adults

    Carmona-Perera, Martina; Martí-García, Celia; Pérez-García, Miguel; Verdejo-García, Antonio

    2013-01-01

    Moral decision-making is a key asset for humans’ integration in social contexts, and the way we decide about moral issues seems to be strongly influenced by emotions. For example, individuals with deficits in emotional processing tend to deliver more utilitarian choices (accepting an emotionally aversive action in favor of communitarian well-being). However, little is known about the association between emotional experience and moral-related patterns of choice. We investigated whether subjective reactivity to emotional stimuli, in terms of valence, arousal, and dominance, is associated with moral decision-making in 95 healthy adults. They answered to a set of moral and non-moral dilemmas and assessed emotional experience in valence, arousal and dominance dimensions in response to neutral, pleasant, unpleasant non-moral, and unpleasant moral pictures. Results showed significant correlations between less unpleasantness to negative stimuli, more pleasantness to positive stimuli and higher proportion of utilitarian choices. We also found a positive association between higher arousal ratings to negative moral laden pictures and more utilitarian choices. Low dominance was associated with greater perceived difficulty over moral judgment. These behavioral results are in fitting with the proposed role of emotional experience in moral choice. PMID:24133433

  16. Are Sexual and Emotional Infidelity Equally Upsetting to Men and Women? Making Sense of Forced-Choice Responses

    David A. Lishner

    2008-10-01

    Full Text Available Forced-choice measures that assess reactions to imagined sexual and emotional infidelity are ubiquitous in studies testing the Jealousy as a Specific Innate Module (JSIM model. One potential problem with such measures is that they fail to identify respondents who find both forms of infidelity equally upsetting. To examine this issue, an experiment was conducted in which two groups of participants imagined a romantic infidelity after which participants in the first group used a traditional forced-choice measure to indicate whether they found sexual or emotional infidelity more upsetting. Participants in the second group instead used a modified forced-choice measure that allowed them also to indicate whether they found both forms of infidelity equally upsetting. Consistent with previous research, those given the traditional forced-choice measure tended to respond in a manner that supported the JSIM model. However, the majority of participants given the modified measure indicated that both forms of infidelity were equally upsetting.

  17. The neuronal substrate of risky choice: an insight into the contributions of neuroimaging to the understanding of theories on decision making under risk.

    Vorhold, Verena

    2008-04-01

    This chapter provides an overview of studies in the field of neuroscience that investigate some of the processes and concepts of risk perception, risky choice, and decision making under risk. First, early studies in the field of neuroscience addressing the diminished decision-making abilities in lesion patients are presented. A classical task in this research field is described along with its neural implications. After this, the underlying model, its hypotheses, and neuronal implications are discussed. Different aspects within risky decision making, such as the influence of memory, inhibition, motivation, and personality, on risky choice and the respective underlying neuronal substrate are described. After this, studies of risky decision making in healthy subjects are reviewed. A selection of studies shows that theories focusing on cognitive aspects only have to be enriched in order to allow for additional aspects within risky decision making (e.g., emotion). Next, the classical economic approaches and the development of theories incorporating further aspects within economical decision making and the underlying neuronal substrate will be presented. Finally, research in the field of neuroeconomics, focusing on the role of social decision making and evaluative judgment within risky decision making, is reviewed.

  18. Mindfulness and mental toughness among provincial adolescent ...

    Kathryn van Boom

    psychological basis of mental toughness from within existing, evidence-based ... development of mental toughness among athletes. The existing studies have ... that advocated by cognitive-behavioural interventions and traditional mental skills ...

  19. Nonsensical choices? Fall armyworm moths choose seemingly best or worst hosts for their larvae, but neonate larvae make their own choices.

    Julio C Rojas

    Full Text Available Selecting optimal host plants is critical for herbivorous insects, such as fall armyworm (Spodoptera frugiperda, an important maize pest in the Americas and Africa. Fall armyworm larvae are presumed to have limited mobility, hence female moths are presumed to be largely responsible for selecting hosts. We addressed host selection by fall armyworm moths and neonate and older (3rd-instar larvae, as mediated by resistance and herbivory in maize plants. Thus, we compared discrimination among three maize cultivars with varying degrees of resistance to fall armyworm, and between plants subjected or not to two types of herbivory. The cultivars were: (i susceptible, and deficient in jasmonic acid (JA production and green leaf volatiles (GLV emissions (inbred line B73-lox10; (ii modestly resistant (B73, and; (iii highly resistant (Mp708. The herbivory types were: (i ongoing (= fall armyworm larvae present, and; (ii future (= fall armyworm eggs present. In choice tests, moths laid more eggs on the highly resistant cultivar, and least on the susceptible cultivar, though on those cultivars larvae performed poorest and best, respectively. In the context of herbivory, moths laid more eggs: (i on plants subject to versus free of future herbivory, regardless of whether plants were deficient or not in JA and GLV production; (ii on plants subject versus free of ongoing herbivory, and; (iii on plants not deficient in compared to deficient in JA and GLV production. Neonate larvae dispersed aerially from host plants (i.e. ballooned, and most larvae colonized the modestly resistant cultivar, and fewest the highly resistant cultivar, suggesting quasi-directional, directed aerial descent. Finally, dispersing older larvae did not discriminate among the three maize cultivars, nor between maize plants and (plastic model maize plants, suggesting random, visually-oriented dispersal. Our results were used to assemble a model of host selection by fall armyworm moths and

  20. Crack arrest toughness measurements with A533B steel

    Salonen, Seppo.

    1979-11-01

    This work covers crack arrest toughness measurements on A533B steel done at the Technical Research Centre of Finland. These measurements are one part of a multinational effort, involving 30 laboratories. The aim of the cooperative test program is to examine two test procedures for measuring the crack arrest toughness, to give information about their reproducibility, and to identify the factors affecting the interpretation. The principles given for the testing were easy to apply in general and the results were satisfactory. Some factors in the test runs and in the specimen's behaviour are indicated which can cause error in the results or make implementation of the test more difficult. By comparing the results from our laboratory with average values from the test program a good agreement can be seen. Crack arrest toughness values derived from the compared procedures with a static analysis agree closely, but values calculated using a dynamic analysis differ considerably. (author)

  1. 46 CFR 154.605 - Toughness test.

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Toughness test. 154.605 Section 154.605 Shipping COAST....605 Toughness test. (a) Each toughness test under §§ 154.610 through 154.625 must meet Subpart 54.05 of this chapter. (b) If subsize test specimens are used for the Charpy V-notch toughness test, the...

  2. Why women of lower educational attainment struggle to make healthier food choices: the importance of psychological and social factors.

    Lawrence, Wendy; Skinner, Chas; Haslam, Cheryl; Robinson, Sian; Inskip, Hazel; Barker, David; Cooper, Cyrus; Jackson, Alan; Barker, Mary

    2009-11-01

    Women of lower educational attainment are more likely to eat unhealthy diets than women of higher educational attainment. To identify influences on the food choices of women with lower educational attainment, 11 focus groups (eight with women of lower, and three with women of higher educational attainment) were held. Using a semi-structured discussion guide, environmental, social, historical and psychological factors known to be associated with food choice were explored. Audio recordings were transcribed verbatim and thematically analysed. Compared to women of higher educational attainment, women of lower educational attainment had less control over their families' food choices, less support for attempts to eat healthily, fewer opportunities to observe and learn good food-related practices, more negative affect, more perceived environmental constraints and more ambiguous beliefs about the consequences of eating a nutritious diet. These findings provide a starting point for taking forward the design of an intervention to improve the diets of young women.

  3. The Effect of Trait Self-Awareness, Self-Reflection, and Perceptions of Choice Meaningfulness on Indicators of Social Identity within a Decision-Making Context.

    Dishon, Noam; Oldmeadow, Julian A; Critchley, Christine; Kaufman, Jordy

    2017-01-01

    Theorists operating from within a narrative identity framework have suggested that self-reflective reasoning plays a central role in the development of the self. Typically, however, narrative identity researchers have investigated this relationship using correlational rather than experimental methods. In the present study, leveraging on a classic research paradigm from within the social identity literature we developed an experiment to test the extent to which self-reflection might have a causal impact on the self-concept within a decision-making context. In a minimal group paradigm participants were prompted to reflect on their painting choices either before or after allocating points to in-group∖ out-group members. As anticipated, self-reflection augmented social identification, but only when participants felt their choices were personally meaningful. Participants who reasoned about their choices and felt they were subjectively meaningful showed stronger similarity and liking for in-group members compared to those who did not reflect on their choices or found them to be subjectively meaningless. Hence, reflecting on and finding meaning in one's choices may be an important step in linking behavior with in-group identification and thus the self-concept in turn. The absence of any effects on in-group favoritism (a third indicator of social identification measured) as well as implications of the study's findings for self-perception, cognitive dissonance and social identity processes are also discussed.

  4. Are medical students influenced by preceptors in making career choices, and if so how? A systematic review.

    Stagg, P; Prideaux, D; Greenhill, J; Sweet, L

    2012-01-01

    Increasingly medical students undertake clinical training in distributed learning environments. The driving factor for this is predominantly to address medical workforce shortages. In these environments students are often taught by private practitioners, residents, house staff and registrars, as well as faculty. Through a mix of short- and long-term preceptorships, clerkships and rotations, medical students are exposed to a wider range of preceptors, mentors and role models than has traditionally been the case. The aim of this systematic review was to understand if and how medical students' career choices are influenced by their interactions with preceptors. A search of Ovid Medline, Scopus, ISI Web of Science, PubMed, Eric and CIHNAL was undertaken. The search was structured around the key terms: Medical Student, Career Choice and Preceptor, and variants of these terms. Search limits were set to English-language publications between 1995 and 2010. A total of 36 articles met the selection criteria from the 533 citations sourced from the search. Required preceptorships as short as 3 weeks' duration influence the career choice of students when they rate the preceptor as a high quality teacher. Preceptors who are judged (by students) as high quality teachers have the greatest influence on student career choice by up to four-fold. When students judged a preceptor as being a negative role model, a poor teacher or lacking discipline specific knowledge they will turn away from that field. The positive influence of relationships between preceptors and students on career choice is strongest where there is continuity of preceptors, continuity of care, and continuity of patient interactions. The longer the duration of the preceptorship the greater the influence on student career choice, particularly in primary cares environments. This review adds to the literature by identifying how differing components and combinations of components of a preceptorship influence medical

  5. Four Takes on Tough Times

    Rebell, Michael A.; Odden, Allan; Rolle, Anthony; Guthrie, James W.

    2012-01-01

    Educational Leadership talks with four experts in the fields of education policy and finance about how schools can weather the current financial crisis. Michael A. Rebell focuses on the recession and students' rights; Allan Odden suggests five steps schools can take to improve in tough times; Anthony Rolle describes the tension between equity and…

  6. Making Good Choices: How Autonomy Support Influences the Behavior Change and Motivation of Troubled and Troubling Youth

    Harper, Elaine

    2007-01-01

    Autonomy is a basic human need having influence on motivation. Facilitating student autonomy is an essential ingredient of effective programs for maximizing internalized change and increasing motivation in troubled and troubling youth. This article examines the theoretical concepts of autonomy and control related to choices and considers their…

  7. "Putting Music On": Everyday Leisure Activities, Choice-Making and Person-Centred Planning in a Supported Living Scheme

    Hassan, Nedim

    2017-01-01

    Background: Person-centred planning, which commonly becomes formalised within services for people with learning disabilities through an Essential Lifestyle Plan (ELP), was intended to help place the choices of individuals at the forefront of service provision. However, beyond UK government policy rhetoric, scholars have raised issues regarding the…

  8. Which Infidelity Type Makes You More Jealous? Decision Strategies in a Forced-Choice between Sexual and Emotional Infidelity

    Achim Schützwohl

    2004-01-01

    This study tested the prediction derived from the evolutionary psychological analysis of jealousy that men and women selecting the adaptively primary infidelity type (i.e., female sexual and male emotional infidelity, respectively) in a forced-choice response format need to engage in less elaborate decision strategies than men and women selecting the adaptively secondary infidelity type (i.e., male sexual and female emotional infidelity, respectively). Unknown to the participants, decision ti...

  9. Α4β2 and α7 nicotinic acetylcholine receptor binding predicts choice preference in two cost benefit decision-making tasks.

    Mendez, I A; Damborsky, J C; Winzer-Serhan, U H; Bizon, J L; Setlow, B

    2013-01-29

    Nicotinic receptors have been linked to a wide range of cognitive and behavioral functions, but surprisingly little is known about their involvement in cost benefit decision making. The goal of these experiments was to determine how nicotinic acetylcholine receptor (nAChR) expression is related to two forms of cost benefit decision making. Male Long Evans rats were tested in probability- and delay-discounting tasks, which required discrete trial choices between a small reward and a large reward associated with varying probabilities of omission and varying delays to reward delivery, respectively. Following testing, radioligand binding to α4β2 and α7 nAChR subtypes in brain regions implicated in cost benefit decision making was examined. Significant linear relationships were observed between choice of the large delayed reward in the delay discounting task and α4β2 receptor binding in both the dorsal and ventral hippocampus. Additionally, trends were found suggesting that choice of the large costly reward in both discounting tasks was inversely related to α4β2 receptor binding in the medial prefrontal cortex and nucleus accumbens shell. Similar trends suggested that choice of the large delayed reward in the delay discounting task was inversely related to α4β2 receptor binding in the orbitofrontal cortex, nucleus accumbens core, and basolateral amygdala, as well as to α7 receptor binding in the basolateral amygdala. These data suggest that nAChRs (particularly α4β2) play both unique and common roles in decisions that require consideration of different types of reward costs. Copyright © 2012 IBRO. Published by Elsevier Ltd. All rights reserved.

  10. A two-layered diffusion model traces the dynamics of information processing in the valuation-and-choice circuit of decision making.

    Piu, Pietro; Fargnoli, Francesco; Innocenti, Alessandro; Rufa, Alessandra

    2014-01-01

    A circuit of evaluation and selection of the alternatives is considered a reliable model in neurobiology. The prominent contributions of the literature to this topic are reported. In this study, valuation and choice of a decisional process during Two-Alternative Forced-Choice (TAFC) task are represented as a two-layered network of computational cells, where information accrual and processing progress in nonlinear diffusion dynamics. The evolution of the response-to-stimulus map is thus modeled by two linked diffusive modules (2LDM) representing the neuronal populations involved in the valuation-and-decision circuit of decision making. Diffusion models are naturally appropriate for describing accumulation of evidence over the time. This allows the computation of the response times (RTs) in valuation and choice, under the hypothesis of ex-Wald distribution. A nonlinear transfer function integrates the activities of the two layers. The input-output map based on the infomax principle makes the 2LDM consistent with the reinforcement learning approach. Results from simulated likelihood time series indicate that 2LDM may account for the activity-dependent modulatory component of effective connectivity between the neuronal populations. Rhythmic fluctuations of the estimate gain functions in the delta-beta bands also support the compatibility of 2LDM with the neurobiology of DM.

  11. An application of the rational choice approach to the offending process of sex offenders: a closer look at the decision-making.

    Beauregard, Eric; Leclerc, Benoît

    2007-06-01

    Although the study of both offense processes and implicit theories provides in-depth knowledge about the decision-making of sex offenders, these studies focus solely on the internal psychological processes of the offender leading to the commission of a sexual assault. These studies neglect to look specifically at the offender's decision-making during the offense in interaction with the immediate situations encountered at the offense scene, such as the choices of behavior while interacting with the victim in a specific context. Based on a rational choice approach, this study investigates the decision-making involved in the offending process of 69 serial sexual offenders who have committed their crimes against stranger victims. Semi-structured interviews were conducted with offenders in order to identify the rationale behind their actions during the pre-crime phase (premeditation of the crime, estimation of risk of apprehension by the offender, and forensic awareness of the offender), crime phase (use of a weapon, use of restraints, use of a vehicle, and level of force used), and the post-crime phase (event leading to the end of crime and victim release site location choice). Results show that sex offenders, even if traditionally described as "irrational" and impulsive individuals, are capable, up to a certain point, of an analysis of the costs/benefits related to their actions. Moreover, results emphasize the important role of situational factors, such as victim resistance, on the decision-making process of sex offenders. Implications of the results are briefly discussed in regard of clinical practice and crime prevention.

  12. Which Infidelity Type Makes You More Jealous? Decision Strategies in a Forced-Choice between Sexual and Emotional Infidelity

    Achim Schützwohl

    2004-01-01

    Full Text Available This study tested the prediction derived from the evolutionary psychological analysis of jealousy that men and women selecting the adaptively primary infidelity type (i.e., female sexual and male emotional infidelity, respectively in a forced-choice response format need to engage in less elaborate decision strategies than men and women selecting the adaptively secondary infidelity type (i.e., male sexual and female emotional infidelity, respectively. Unknown to the participants, decision times were registered as an index of the elaborateness of their decision strategies. The results clearly support the prediction. Implications and limitations of the present findings are discussed.

  13. Kid-Friendly Veggies and Fruits: 10 Tips for Making Healthy Food Choices More Fun for Children

    ... Set up a pizza-making station in the kitchen. Use whole-wheat English muffins, bagels, or pita ... veggies or fruits into a fun shape or design. 5 fruity peanut butterfly Start with carrot sticks ...

  14. Affective and rational consumer choice modes: The role of intuition, analytical decision-making, and attitudes to money

    Andersson, Patric; Engelberg, Elisabeth

    2006-01-01

    This paper was motivated by a paucity of research addressing how consumer decision-making is related to beliefs about money and different modes of reasoning. To investigate this issue, data were collected from 142 participants, who filled out questionnaires involving scales aimed to measure affective and rational purchase approaches, intuitive and analytical decision-making styles, as well as money attitudes. One finding was that consumers interchangeably rely on affective and rational approa...

  15. Tough Choices in Designing a Formative Assessment System

    Sharkey, Nancy S.; Murnane, Richard J.

    2006-01-01

    A growing number of school districts in the United States are introducing formative assessment systems to measure student skills in core subjects throughout the year. The underlying logic is that providing teachers with timely information on student skills will enable them to improve instruction and better prepare students to excel on high-stakes,…

  16. Bayesian deterministic decision making: A normative account of the operant matching law and heavy-tailed reward history dependency of choices

    Hiroshi eSaito

    2014-03-01

    Full Text Available The decision making behaviors of humans and animals adapt and then satisfy an ``operant matching law'' in certain type of tasks. This was first pointed out by Herrnstein in his foraging experiments on pigeons. The matching law has been one landmark for elucidating the underlying processes of decision making and its learning in the brain. An interesting question is whether decisions are made deterministically or probabilistically. Conventional learning models of the matching law are based on the latter idea; they assume that subjects learn choice probabilities of respective alternatives and decide stochastically with the probabilities. However, it is unknown whether the matching law can be accounted for by a deterministic strategy or not. To answer this question, we propose several deterministic Bayesian decision making models that have certain incorrect beliefs about an environment. We claim that a simple model produces behavior satisfying the matching law in static settings of a foraging task but not in dynamic settings. We found that the model that has a belief that the environment is volatile works well in the dynamic foraging task and exhibits undermatching, which is a slight deviation from the matching law observed in many experiments. This model also demonstrates the double-exponential reward history dependency of a choice and a heavier-tailed run-length distribution, as has recently been reported in experiments on monkeys.

  17. End-of-life decision making in respiratory failure. The therapeutic choices in chronic respiratory failure in a 7-item questionnaire

    Dagmar Elfriede Rinnenburger

    2012-01-01

    Full Text Available INTRODUCTION: The transition from paternalistic medicine to a healthcare culture centred on the patient's decision making autonomy presents problems of communication and understanding. Chronic respiratory failure challenges patients, their families and caregivers with important choices, such as invasive and non-invasive mechanical ventilation and tracheostomy, which, especially in the case of neuromuscular diseases, can significantly postpone the end of life. MATERIAL AND METHODS: A 7-item questionnaire was administered to 100 patients with advanced COPD, neuromuscular diseases and pulmonary fibrosis, all of them on oxygen therapy and receiving day-hospital treatment for respiratory failure. The objective was to find out whether or not patients, if faced with a deterioration of their health condition, would want to take part in the decision making process and, if so, how and with whom. RESULTS. Results showed that: 90% of patients wanted to be interviewed, 10% preferred not to be interviewed, 82% wanted to be regularly updated on their clinical situation, 75% wanted to be intubated, if necessary, and 56% would also agree to have a tracheostomy. These choices have been confirmed one year later, with 93% of respondents accepting the questionnaire and considering it useful. CONCLUSIONS: It is possible to conclude that a simple questionnaire can be a useful tool contributing to therapeutic decision making in respiratory failure.

  18. Market Exchange Rates Or Purchasing Power Parity. Does The Choice Make A Difference To The Climate Debate?

    Manne, A.S.; Richels, R.G.; Edmonds, J.A.

    2005-01-01

    Critics of the Intergovernmental Panel on Climate Change's Special Report on Emission Scenarios claim that the use of market exchange rates (MER) rather than purchasing power parity (PPP) to measure gross domestic product (GDP) has led to a significant upward bias in projections of greenhouse gas emissions, and hence unrealistically high future temperature. Rather than revisit the debate on the choice of exchange rates, we address a much simpler question: when it comes to temperature change, how much does it matter if potential GDP is expressed in MER rather than PPP? Employing a computable general equilibrium model designed to examine a variety of issues in the climate debate, we find that there is a difference, but that it is only minor

  19. Independence and interdependence in collective decision making: an agent-based model of nest-site choice by honeybee swarms

    List, Christian; Elsholtz, Christian; Seeley, Thomas D.

    2008-01-01

    Condorcet's jury theorem shows that when the members of a group have noisy but independent information about what is best for the group as a whole, majority decisions tend to outperform dictatorial ones. When voting is supplemented by communication, however, the resulting interdependencies between decision makers can strengthen or undermine this effect: they can facilitate information pooling, but also amplify errors. We consider an intriguing non-human case of independent information pooling combined with communication: the case of nest-site choice by honeybee (Apis mellifera) swarms. It is empirically well documented that when there are different nest sites that vary in quality, the bees usually choose the best one. We develop a new agent-based model of the bees' decision process and show that its remarkable reliability stems from a particular interplay of independence and interdependence between the bees. PMID:19073474

  20. Fracture toughness testing on ferritic alloys using the electropotential technique

    Huang, F.H.; Wire, G.L.

    1981-01-01

    Fracture toughness measurements as done conventionally require large specimens (5 x 5 x 2.5 cm) which would be prohibitively expensive to irradiate over the fluence and temperature ranges required for first wall design. To overcome this difficulty a single specimen technique for J intergral fracture toughness measurements on miniature specimens (1.6 cm OD x 0.25 cm thick) was developed. Comparisons with specimens three times as thick show that the derived J/sub 1c/ is constant, validating the specimen for first wall applications. The electropotential technique was used to obtain continuous crack extension measurements, allowing a ductile fracture resistence curve to be constructed from a single specimen. The irradiation test volume required for fracture toughness measurements using both miniature specimens and single specimen J measurements was reduced a factor of 320, making it possible to perform a systematic exploration of irradiation temperature and dose variables as required for qualification of HT-9 and 9Cr-1Mo base metal and welds for first wall application. Fracture toughness test results for HT-9 and 9Cr-1Mo from 25 to 539 0 C are presented to illustrate the single specimen technique

  1. Use of classical criterions of a decision making for choice of measures on decrease of economic damage from nuclear and radiation accidents

    Rylov, M.I.; Kamynov, Sh.V.; Mozhaev, A.S.; Anisimov, N.A.; Nikitin, V.S.

    2004-01-01

    Application of classical criteria of decision making for choice of measures on the decrease of economic damage from possible nuclear and radiation accidents during spent fuel unloading from nuclear submarines and storage in the process of their utilization was demonstrated. Economic damage was chosen as optimization index, three versions of possible accidents and limited number of measures on the decrease of their effect were treated for illustration of the suggested approach. On the base of analysis of classical criteria the optimal strategy for decrease of economic damage was chosen [ru

  2. Ion implantation and fracture toughness of ceramics

    Clark, J.; Pollock, J.T.A.

    1985-01-01

    Ceramics generally lack toughness which is largely determined by the ceramic surface where stresses likely to cause failure are usually highest. Ion implantation has the capacity to improve the surface fracture toughness of ceramics. Significantly reduced ion size and reactivity restrictions exist compared with traditional methods of surface toughening. We are studying the effect of ion implantation on ceramic fracture toughness using indentation testing as the principal tool of analysis

  3. Choice Shifts in Groups

    Kfir Eliaz; Debraj Ray

    2004-01-01

    The phenomenon of "choice shifts" in group decision-making is fairly ubiquitous in the social psychology literature. Faced with a choice between a ``safe" and ``risky" decision, group members appear to move to one extreme or the other, relative to the choices each member might have made on her own. Both risky and cautious shifts have been identified in different situations. This paper demonstrates that from an individual decision-making perspective, choice shifts may be viewed as a systematic...

  4. Mental toughness latent profiles in endurance athletes.

    Zeiger, Joanna S; Zeiger, Robert S

    2018-01-01

    Mental toughness in endurance athletes, while an important factor for success, has been scarcely studied. An online survey was used to examine eight mental toughness factors in endurance athletes. The study aim was to determine mental toughness profiles via latent profile analysis in endurance athletes and whether associations exist between the latent profiles and demographics and sports characteristics. Endurance athletes >18 years of age were recruited via social media outlets (n = 1245, 53% female). Mental toughness was measured using the Sports Mental Toughness Questionnaire (SMTQ), Psychological Performance Inventory-Alternative (PPI-A), and self-esteem was measured using the Rosenberg Self-Esteem Scale (RSE). A three-class solution emerged, designated as high mental toughness (High MT), moderate mental toughness (Moderate MT) and low mental toughness (Low MT). ANOVA tests showed significant differences between all three classes on all 8 factors derived from the SMTQ, PPI-A and the RSE. There was an increased odds of being in the High MT class compared to the Low MT class for males (OR = 1.99; 95% CI, 1.39, 2.83; Pathletes who were over 55 compared to those who were 18-34 (OR = 2.52; 95% CI, 1.37, 4.62; Pathletes. High MT is associated with demographics and sports characteristics. Mental toughness screening in athletes may help direct practitioners with mental skills training.

  5. Formation of tough composite joints

    Brun, M.K.

    1997-05-01

    Joints which exhibit tough fracture behavior were formed in a composite with a Si/SiC matrix reinforced with Textron SCS-6 fibers with either boron nitride or silicon nitride fiber coatings. In composites with BN coatings fibers were aligned uniaxially, while composites with Si 3 N 4 -coated fibers had a 0/90 degree architecture. Lapped joints (joints with overlapping fingers) were necessary to obtain tough behavior. Geometrical requirements necessary to avoid brittle joint failure have been proposed. Joints with a simple overlap geometry (only a few fingers) would have to be very long in order to prevent brittle failure. Typical failure in these joints is caused by a crack propagating along the interfaces between the joint fingers. Joints of the same overall length, but with geometry changed to be symmetric about the joint centerline and with an extra shear surface exhibited tough fractures accompanied with extensive fiber pullout. The initial matrix cracking of these joints was relatively low because cracks propagated easily through the ends of the fingers. Joints with an optimized stepped sawtooth geometry produced composite-like failures with the stress/strain curves containing an elastic region followed by a region of rising stress with an increase of strain. Increasing the fiber/matrix interfacial strength from 9 to 25 MPa, by changing the fiber coating, increased matrix cracking and ultimate strength of the composite significantly. The best joints had matrix cracking stress and ultimate strength of 138 and 240 MPa, respectively. Joint failure was preceded by multiple matrix cracking in the entire composite. The high strength of the joints will permit building of structures containing joints with only a minor reduction of design stresses

  6. What choices should we be able to make about designer babies? A Citizens' Jury of young people in South Wales.

    Iredale, Rachel; Longley, Marcus; Thomas, Christian; Shaw, Anita

    2006-09-01

    Young people will increasingly have the option of using new technologies for reproductive decision making but their voices are rarely heard in debates about acceptable public policy in this area. Capturing the views of young people about potentially esoteric topics, such as genetics, is difficult and methodologically challenging. A Citizens' Jury is a deliberative process that presents a question to a group of ordinary people, allows them to examine evidence given by expert witnesses and personal testimonies and arrive at a verdict. This Citizens' Jury explored designer babies in relation to inherited conditions, saviour siblings and sex selection with young people. Fourteen young people aged 16-19 in Wales. Acceptance of designer baby technology was purpose-specific; it was perceived by participants to be acceptable for preventing inherited conditions and to create a child to save a sibling, but was not recommended for sex selection. Jurors stated that permission should not depend on parents' age, although some measure of suitability should be assessed. Preventing potential parents from going abroad was considered impractical. These young people felt the Human Fertilisation and Embryology Authority should have members under 20 and that the term 'designer baby' was not useful. Perspectives on the acceptability of this technology were nuanced, and based on implicit value judgements about the extent of individual benefit derived. Young people have valuable and interesting contributions to make to the debate about genetics and reproductive decision making and a variety of innovative methods must be used to secure their involvement in decision-making processes.

  7. Hydrogen fracture toughness tester completion

    Morgan, Michael J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-09-30

    The Hydrogen Fracture Toughness Tester (HFTT) is a mechanical testing machine designed for conducting fracture mechanics tests on materials in high-pressure hydrogen gas. The tester is needed for evaluating the effects of hydrogen on the cracking properties of tritium reservoir materials. It consists of an Instron Model 8862 Electromechanical Test Frame; an Autoclave Engineering Pressure Vessel, an Electric Potential Drop Crack Length Measurement System, associated computer control and data acquisition systems, and a high-pressure hydrogen gas manifold and handling system.

  8. Making healthy food choices using nutrition facts panels. The roles of knowledge, motivation, dietary modifications goals, and age.

    Miller, Lisa M Soederberg; Cassady, Diana L

    2012-08-01

    Nutrition facts panels (NFPs) contain a rich assortment of nutrition information and are available on most food packages. The importance of this information is potentially even greater among older adults due to their increased risk for diet-related diseases, as well as those with goals for dietary modifications that may impact food choice. Despite past work suggesting that knowledge and motivation impact attitudes surrounding and self-reported use of NFPs, we know little about how (i.e., strategies used) and how well (i.e., level of accuracy) younger and older individuals process NFP information when evaluating healthful qualities of foods. We manipulated the content of NFPs and, using eye tracking methodology, examined strategies associated with deciding which of two NFPs, presented side-by-side, was healthier. We examined associations among strategy use and accuracy as well as age, dietary modification status, knowledge, and motivation. Results showed that, across age groups, those with dietary modification goals made relatively more comparisons between NFPs with increasing knowledge and motivation; but that strategy effectiveness (relationship to accuracy) depended on age and motivation. Results also showed that knowledge and motivation may protect against declines in accuracy in later life and that, across age and dietary modification status, knowledge mediates the relationship between motivation and decision accuracy. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. A systematic literature review of nutrition interventions in vending machines that encourage consumers to make healthier choices.

    Grech, A; Allman-Farinelli, M

    2015-12-01

    Internationally, vending machines are scrutinized for selling energy-dense nutrient-poor foods and beverages, and the contribution to overconsumption and subsequent risk of obesity. The aim of this review is to determine the efficacy of nutrition interventions in vending machine in eliciting behaviour change to improve diet quality or weight status of consumers. Electronic databases Cochrane, EMBASE, CINAHL, Science Direct and PubMed were searched from inception. (i) populations that have access to vending machines; (ii) nutrition interventions; (iii) measured outcomes of behaviour change (e.g. sales data, dietary intake or weight change); and (iv) experimental trials where controls were not exposed to the intervention. Risk of bias was assessed independently by two researchers, and higher quality research formed the basis of this qualitative review. Twelve articles from 136 searched were included for synthesis. Intervention settings included schools, universities and workplaces. Reducing price or increasing the availability increased sales of healthier choices. The results of point-of-purchase nutrition information interventions were heterogeneous and when measured changes to purchases were small. This review offers evidence that pricing and availability strategies are effective at improving the nutritional quality foods and beverages purchased from vending machines. Evidence on how these interventions alter consumer's overall diet or body mass index is needed. © 2015 World Obesity.

  10. Making Healthy Food Choices Using Nutrition Facts Panels: The Roles of Knowledge, Motivation, Dietary Modifications Goals, and Age

    Cassady, Diana L.

    2012-01-01

    Nutrition facts panels (NFPs) contain a rich assortment of nutrition information and are available on most food packages. The importance of this information is potentially even greater among older adults due to their increased risk for diet-related diseases, as well as those with goals for dietary modifications that may impact food choice. Despite past work suggesting that knowledge and motivation impact attitudes surrounding and self-reported use of NFPs, we know little about how (i.e., strategies used) and how well (i.e., level of accuracy) younger and older individuals process NFP information when evaluating healthful qualities of foods. We manipulated the content of NFPs and, using eye tracking methodology, examined strategies associated with deciding which of two NFPs, presented side-by-side, was healthier. We examined associations among strategy use and accuracy as well as age, dietary modification status, knowledge, and motivation. Results showed that, across age groups, those with dietary modification goals made relatively more comparisons between NFPs with increasing knowledge and motivation; but that strategy effectiveness (relationship to accuracy) depended on age and motivation. Results also showed that knowledge and motivation may protect against declines in accuracy in later life and that, across age and dietary modification status, knowledge mediates the relationship between motivation and decision accuracy. PMID:22524999

  11. On framing effects in decision making: linking lateral versus medial orbitofrontal cortex activation to choice outcome processing.

    Windmann, Sabine; Kirsch, Peter; Mier, Daniela; Stark, Rudolf; Walter, Bertram; Güntürkün, Onur; Vaitl, Dieter

    2006-07-01

    Two correlates of outcome processing in the orbitofrontal cortex (OFC) have been proposed in the literature: One hypothesis suggests that the lateral/medial division relates to representation of outcome valence (negative vs. positive), and the other suggests that the medial OFC maintains steady stimulus-outcome associations, whereas the lateral OFC represents changing (unsteady) outcomes to prepare for response shifts. These two hypotheses were contrasted by comparing the original with the inverted version of the Iowa Gambling Task in an event-related functional magnetic resonance imaging experiment. Results showed (1) that (caudo) lateral OFC was indeed sensitive to the steadiness of the outcomes and not merely to outcome valence and (2) that the original and the inverted tasks, although both designed to measure sensitivity for future outcomes, were not equivalent as they enacted different behaviors and brain activation patterns. Results are interpreted in terms of Kahneman and Tversky's prospect theory suggesting that cognitions and decisions are biased differentially when probabilistic future rewards are weighed against consistent punishments relative to the opposite scenario [Kahneman, D., & Tversky, A. Choices, values, and frames. American Psychologist, 39, 341-350, 1984]. Specialized processing of unsteady rewards (involving caudolateral OFC) may have developed during evolution in support of goal-related thinking, prospective planning, and problem solving.

  12. Percutaneous imaging-guided treatment of hydatid liver cysts: Do long-term results make it a first choice?

    Kabaalioglu, Adnan; Ceken, Kagan; Alimoglu, Emel; Apaydin, Ali

    2006-01-01

    Aim: To evaluate the long-term results of percutaneous imaging-guided treatment of hydatid liver cysts. Materials and methods: Sixty patients with 77 hydatid liver cysts underwent percutaneous treatment with ultrasonography (US) or computed tomography (CT) guidance. Absolute alcohol and hypertonic saline were used for sclerosing the cysts after aspiration. Prophylactic albendazole treatment was given before and after the procedures. Follow-up US and CT were obtained periodically, and changes in cyst morphology were recorded. Minimum follow-up period for the patients included in this study was 12 months. Serological correlation was also available for a group of patients. The outcome of the procedures were categorized into five groups based on morphological changes observed by imaging. Results: Procedures were regarded as successful in 80% and unsuccessful in 20% of patients. Failures most often occurred with type III cysts; less than half (39%) of the total type III cysts had a successful outcome. On the other hand, all type I cysts ended up with cure. Anaphylaxis, pneumotorax and severe pain interrupting the procedures were also among the reasons of failure. Conclusion: Percutaneous aspiration, injection and reaspiration (PAIR) of types I and II hydatid liver cysts is effective and safe in the long-term. Surgery should no longer be regarded as the first choice treatment in all hydatid liver cysts but should be reserved for type III and certain active type IV cysts

  13. Percutaneous imaging-guided treatment of hydatid liver cysts: Do long-term results make it a first choice?

    Kabaalioglu, Adnan [Department of Radiology, Akdeniz University Hospital, Antalya (Turkey)]. E-mail: adnank@akdeniz.edu.tr; Ceken, Kagan [Department of Radiology, Akdeniz University Hospital, Antalya (Turkey); Alimoglu, Emel [Department of Radiology, Akdeniz University Hospital, Antalya (Turkey); Apaydin, Ali [Department of Radiology, Akdeniz University Hospital, Antalya (Turkey)

    2006-07-15

    Aim: To evaluate the long-term results of percutaneous imaging-guided treatment of hydatid liver cysts. Materials and methods: Sixty patients with 77 hydatid liver cysts underwent percutaneous treatment with ultrasonography (US) or computed tomography (CT) guidance. Absolute alcohol and hypertonic saline were used for sclerosing the cysts after aspiration. Prophylactic albendazole treatment was given before and after the procedures. Follow-up US and CT were obtained periodically, and changes in cyst morphology were recorded. Minimum follow-up period for the patients included in this study was 12 months. Serological correlation was also available for a group of patients. The outcome of the procedures were categorized into five groups based on morphological changes observed by imaging. Results: Procedures were regarded as successful in 80% and unsuccessful in 20% of patients. Failures most often occurred with type III cysts; less than half (39%) of the total type III cysts had a successful outcome. On the other hand, all type I cysts ended up with cure. Anaphylaxis, pneumotorax and severe pain interrupting the procedures were also among the reasons of failure. Conclusion: Percutaneous aspiration, injection and reaspiration (PAIR) of types I and II hydatid liver cysts is effective and safe in the long-term. Surgery should no longer be regarded as the first choice treatment in all hydatid liver cysts but should be reserved for type III and certain active type IV cysts.

  14. What choices should we be able to make about designer babies? A Citizens’ Jury of young people in South Wales

    Iredale, Rachel; Longley, Marcus; Thomas, Christian; Shaw, Anita

    2006-01-01

    Abstract Background  Young people will increasingly have the option of using new technologies for reproductive decision making but their voices are rarely heard in debates about acceptable public policy in this area. Capturing the views of young people about potentially esoteric topics, such as genetics, is difficult and methodologically challenging. Design  A Citizens’ Jury is a deliberative process that presents a question to a group of ordinary people, allows them to examine evidence given by expert witnesses and personal testimonies and arrive at a verdict. This Citizens’ Jury explored designer babies in relation to inherited conditions, saviour siblings and sex selection with young people. Participants  Fourteen young people aged 16–19 in Wales. Results  Acceptance of designer baby technology was purpose‐specific; it was perceived by participants to be acceptable for preventing inherited conditions and to create a child to save a sibling, but was not recommended for sex selection. Jurors stated that permission should not depend on parents’ age, although some measure of suitability should be assessed. Preventing potential parents from going abroad was considered impractical. These young people felt the Human Fertilisation and Embryology Authority should have members under 20 and that the term ‘designer baby’ was not useful. Conclusions  Perspectives on the acceptability of this technology were nuanced, and based on implicit value judgements about the extent of individual benefit derived. Young people have valuable and interesting contributions to make to the debate about genetics and reproductive decision making and a variety of innovative methods must be used to secure their involvement in decision‐making processes. PMID:16911135

  15. Experiences and Motives of Australian Single Mothers by Choice who make Early Contact with their Child?s Donor Relatives

    Kelly, Fiona J; Dempsey, Deborah J

    2017-01-01

    Abstract An increasing number of Australian parents of donor-conceived children are making contact with their child?s donor relatives prior to their child reaching the age of majority. This process, often referred to as ?donor linking?, can be achieved in Australia through either formal or informal mechanisms. Formal mechanisms exist in three states, each of which has legislation enabling donor linking in certain circumstances. Donor linking may also be achieved through informal mechanisms, s...

  16. The art of grocery shopping on a food stamp budget: factors influencing the food choices of low-income women as they try to make ends meet.

    Wiig, Kristen; Smith, Chery

    2009-10-01

    Amidst a hunger-obesity paradox, the purpose of the present study was to examine the grocery shopping behaviour and food stamp usage of low-income women with children to identify factors influencing their food choices on a limited budget. Focus groups, which included questions based on Social Cognitive Theory constructs, examined food choice in the context of personal, behavioural and environmental factors. A quantitative grocery shopping activity required participants to prioritize food purchases from a 177-item list on a budget of $US 50 for a one-week period, an amount chosen based on the average household food stamp allotment in 2005. Ninety-two low-income women, with at least one child aged 9-13 years in their household, residing in the Twin Cities, Minnesota, USA. Participants' mean age was 37 years, and 76% were overweight or obese (BMI> or =25.0 kg/m2). Key findings suggest that their food choices and grocery shopping behaviour were shaped by not only individual and family preferences, but also their economic and environmental situation. Transportation and store accessibility were major determinants of shopping frequency, and they used various strategies to make their food dollars stretch (e.g. shopping based on prices, in-store specials). Generally, meat was the most important food group for purchase and consumption, according to both the qualitative and quantitative data. Efforts to improve food budgeting skills, increase nutrition knowledge, and develop meal preparation strategies involving less meat and more fruits and vegetables, could be valuable in helping low-income families nutritionally make the best use of their food dollars.

  17. Preparing Parents to Make An Informed Choice About Antibiotic Use for Common Acute Respiratory Infections in Children: A Randomised Trial of Brief Decision Aids in a Hypothetical Scenario.

    Coxeter, Peter D; Del Mar, Chris B; Hoffmann, Tammy C

    2017-08-01

    Childhood acute respiratory infections (ARIs) are one of the most common reasons for primary care consultations and for receiving an antibiotic. Public awareness of antibiotic benefit and harms for these conditions is low. To facilitate informed decision making, ideally in collaboration with their doctor, parents need clear communication about benefits and harms. Decision aids may be able to facilitate this process. The aim of this study was to evaluate the effectiveness of three decision aids about antibiotic use for common ARIs in children. Adult parents of children aged 1-16 years (n = 120) were recruited from community settings and then randomised using a computer-generated randomisation sequence to receive a decision aid (n = 60) or fact sheet (n = 60). Allocation was concealed and used sealed and opaque sequentially numbered envelopes. Participants self-completed questionnaires at baseline and immediately post-intervention. The primary outcome was informed choice (conceptual and numerical knowledge; attitudes towards, and intention to use, antibiotics for a future ARI). Secondary outcomes were decisional conflict, decisional self-efficacy, and material acceptability. After reading the information, significantly more intervention group participants made an informed choice [57%] compared with control group participants [29%] [difference 28, 95% confidence interval (CI) 11-45%, p decision aids prepared parents to make an informed choice about antibiotic use more than fact sheets, in a hypothetical situation. Their effect within a consultation needs to be evaluated. Clinical Trials Registration Number: ACTRN12615000843550.

  18. Proceedings of the TOUGH workshop

    Pruess, K. [ed.

    1990-09-01

    A workshop on applications and enhancements of the TOUGH/MULKOM family of multiphase fluid and heat flow simulation programs was held at Lawrence Berkeley Laboratory on September 13--14, 1990. The workshop was attended by 62 scientists from seven countries with interests in geothermal reservoir engineering, nuclear waste isolation, unsaturated zone hydrology, environmental problems, and laboratory and field experimentation. The meeting featured 21 technical presentations, extended abstracts of which are reproduced in the present volume in unedited form. Simulator applications included processes on a broad range of space scales, from centimeters to kilometers, with transient times from seconds to geologic time scales. A number of code enhancements were reported that increased execution speeds for large 3-D problems by factors of order 20, reduced memory requirements, and improved user-friendliness. The workshop closed with an open discussion session that focussed on future needs and means for interaction in the TOUGH user community. Input from participants was gathered by means of a questionnaire that is reproduced in the appendix. 171 refs., 91 figs., 16 tabs.

  19. Proceedings of the TOUGH workshop

    Pruess, K.

    1990-09-01

    A workshop on applications and enhancements of the TOUGH/MULKOM family of multiphase fluid and heat flow simulation programs was held at Lawrence Berkeley Laboratory on September 13--14, 1990. The workshop was attended by 62 scientists from seven countries with interests in geothermal reservoir engineering, nuclear waste isolation, unsaturated zone hydrology, environmental problems, and laboratory and field experimentation. The meeting featured 21 technical presentations, extended abstracts of which are reproduced in the present volume in unedited form. Simulator applications included processes on a broad range of space scales, from centimeters to kilometers, with transient times from seconds to geologic time scales. A number of code enhancements were reported that increased execution speeds for large 3-D problems by factors of order 20, reduced memory requirements, and improved user-friendliness. The workshop closed with an open discussion session that focussed on future needs and means for interaction in the TOUGH user community. Input from participants was gathered by means of a questionnaire that is reproduced in the appendix. 171 refs., 91 figs., 16 tabs

  20. Fracture toughness of Charpy-size compound specimens and its application in engineering

    Zhang, X.P.; Shi, Y.W.

    1994-01-01

    The use of a pre-cracked Charpy-size specimen with a side-groove to evaluate the fracture toughness of materials has been researched and considered. This method not only satisfies the demand for small-size specimens in surveillance tests of fracture toughness but also avoids using complicated physical methods to monitor the initial conditions of crack propagation. For most materials this method has solved the problem in which the small-size specimen did not satisfy the valid conditions of a fracture toughness measurement. In order to obtain more information from neutron-irradiated sample specimens and raise the reliability of fracture toughness surveillance tests, it has been considered more important to repeatedly exploit the broken Charpy-size specimen tested in the surveillance test, and to make it renewable. In this work, on the renewing design and utilization of Charpy-size specimens, nine data on fracture toughness can be obtained from one pre-cracked side-grooved Charpy-size specimen, while at present usually only one to three data on fracture toughness can be obtained from one Charpy-size specimen. Thus, it is found that the new method would improve the reliability of fracture toughness surveillance testing and evaluation. In addition, some factors that affect the optimum design of pre-cracked deep side-groove Charpy-size compound specimens have also been discussed. (author)

  1. Perspectives of self-direction: a systematic review of key areas contributing to service users' engagement and choice-making in self-directed disability services and supports.

    Lakhani, Ali; McDonald, Donna; Zeeman, Heidi

    2018-05-01

    Self-directed disability support policies aim to encourage greater choice and control for service users in terms of the health and social care they receive. The proliferation of self-directed disability support policies throughout the developed world has resulted in a growing amount of research exploring the outcomes for service users, and their families and carers. Our understanding of the issues faced by people with disabilities, particularly how they make health and social care decisions and the key areas that determine their engagement with service providers within a self-directed environment is limited. A synthesis of research is timely and can provide knowledge for service users and health and social care support providers to ensure their successful participation. A systematic review guided by the PRISMA approach explored (i) the key areas determining service users' engagement with self-directed disability services and supports, and (ii) how service users make informed decisions about providers. In October 2014 and April 2016, three databases - MEDLINE, CINAHL and Web of Science - were searched for research and review articles. Eighteen sources met the search criteria. Findings were mapped into either: key areas determining service user engagement, or service users' informed decision-making. Findings concerning key areas determining engagement fell into three themes - personal responsibility for budgeting, personalised approaches, and a cultural shift in practice and delivery among service providers. Findings about decision-making yielded two themes - supporting informed decision-making and inhibiting informed decision-making. Literature suggests that self-directed models of care may provide service users with increased control over the services that they receive. Increased control for some service users and their families requires independent external decision-making support, particularly around the domains of budgeting, planning and hiring. Future research

  2. Make

    Frauenfelder, Mark

    2012-01-01

    The first magazine devoted entirely to do-it-yourself technology projects presents its 29th quarterly edition for people who like to tweak, disassemble, recreate, and invent cool new uses for technology. MAKE Volume 29 takes bio-hacking to a new level. Get introduced to DIY tracking devices before they hit the consumer electronics marketplace. Learn how to build an EKG machine to study your heartbeat, and put together a DIY bio lab to study athletic motion using consumer grade hardware.

  3. Can Walking or Biking to Work Really Make a Difference? Compact Development, Observed Commuter Choice and Body Mass Index.

    Wojan, Timothy R; Hamrick, Karen S

    2015-01-01

    Promoting active commuting is viewed as one strategy to increase physical activity and improve the energy balance of more sedentary individuals thereby improving health outcomes. However, the potential effectiveness of promotion policies may be seriously undermined by the endogenous choice of commute mode. Policy to promote active commuting will be most effective if it can be demonstrated that 1) those in compact cities do not necessarily have a preference for more physical activity, and 2) that current active commuting is not explained by unobserved characteristics that may be the true source of a lower body mass index (BMI). Daily time-use diaries are used in combination with geographical characteristics of where respondents live and work to test 1) whether residents of more compact settlements are characterized by higher activity levels; and 2) whether residents of more compact settlements are more likely to bike or walk to work. An endogenous treatment model of active commuting allows testing whether reductions in BMI associated with walking or biking to work are in fact attributable to that activity or are more strongly associated with unobserved characteristics of these active commuters. The analysis of general activity levels confirms that residents of more compact cities do not expend more energy than residents of more sprawling cities, indicating that those in compact cities do not necessarily have a preference for more physical activity. The endogenous treatment model is consistent with walking or biking to work having an independent effect on BMI, as unobserved factors that contribute to a higher likelihood of active commuting are not associated with lower BMI. Despite evidence that more compact settlement patterns enable active commuting, only a small share of workers in these areas choose to walk or bike to work. In general, the activity level of residents in more compact cities and residents in more sprawling areas is very similar. But, there is a

  4. Can Walking or Biking to Work Really Make a Difference? Compact Development, Observed Commuter Choice and Body Mass Index.

    Timothy R Wojan

    Full Text Available Promoting active commuting is viewed as one strategy to increase physical activity and improve the energy balance of more sedentary individuals thereby improving health outcomes. However, the potential effectiveness of promotion policies may be seriously undermined by the endogenous choice of commute mode. Policy to promote active commuting will be most effective if it can be demonstrated that 1 those in compact cities do not necessarily have a preference for more physical activity, and 2 that current active commuting is not explained by unobserved characteristics that may be the true source of a lower body mass index (BMI.Daily time-use diaries are used in combination with geographical characteristics of where respondents live and work to test 1 whether residents of more compact settlements are characterized by higher activity levels; and 2 whether residents of more compact settlements are more likely to bike or walk to work. An endogenous treatment model of active commuting allows testing whether reductions in BMI associated with walking or biking to work are in fact attributable to that activity or are more strongly associated with unobserved characteristics of these active commuters.The analysis of general activity levels confirms that residents of more compact cities do not expend more energy than residents of more sprawling cities, indicating that those in compact cities do not necessarily have a preference for more physical activity. The endogenous treatment model is consistent with walking or biking to work having an independent effect on BMI, as unobserved factors that contribute to a higher likelihood of active commuting are not associated with lower BMI.Despite evidence that more compact settlement patterns enable active commuting, only a small share of workers in these areas choose to walk or bike to work. In general, the activity level of residents in more compact cities and residents in more sprawling areas is very similar. But

  5. Making sense of the "clean label" trends: A review of consumer food choice behavior and discussion of industry implications.

    Asioli, Daniele; Aschemann-Witzel, Jessica; Caputo, Vincenzina; Vecchio, Riccardo; Annunziata, Azzurra; Næs, Tormod; Varela, Paula

    2017-09-01

    Consumers in industrialized countries are nowadays much more interested in information about the production methods and components of the food products that they eat, than they had been 50years ago. Some production methods are perceived as less "natural" (i.e. conventional agriculture) while some food components are seen as "unhealthy" and "unfamiliar" (i.e. artificial additives). This phenomenon, often referred to as the "clean label" trend, has driven the food industry to communicate whether a certain ingredient or additive is not present or if the food has been produced using a more "natural" production method (i.e. organic agriculture). However, so far there is no common and objective definition of clean label. This review paper aims to fill the gap via three main objectives, which are to a) develop and suggest a definition that integrates various understandings of clean label into one single definition, b) identify the factors that drive consumers' choices through a review of recent studies on consumer perception of various food categories understood as clean label with the focus on organic, natural and 'free from' artificial additives/ingredients food products and c) discuss implications of the consumer demand for clean label food products for food manufacturers as well as policy makers. We suggest to define clean label, both in a broad sense, where consumers evaluate the cleanliness of product by assumption and through inference looking at the front-of-pack label and in a strict sense, where consumers evaluate the cleanliness of product by inspection and through inference looking at the back-of-pack label. Results show that while 'health' is a major consumer motive, a broad diversity of drivers influence the clean label trend with particular relevance of intrinsic or extrinsic product characteristics and socio-cultural factors. However, 'free from' artificial additives/ingredients food products tend to differ from organic and natural products. Food

  6. Making Communication Strategy Choices in a Fast Evolving Crisis Situation—Results from a Table-Top Discussion on an Anthrax Scenario

    Aino Ruggiero

    2016-05-01

    Full Text Available This paper aims at clarifying a timely topic of how communication strategy choices are made in evolving, complex crises, such as those caused by terrorism involving chemical, biological, radiological, or nuclear (CBRN agents. This is done by examining data gathered from a table-top discussion among crisis communication experts, focusing on a scenario of an anthrax attack and analysed qualitatively. The communication experts followed the evolving crisis situation by gathering inputs from various actors in the crisis management network, thereby creating situational understanding, and interpreted these inputs for decision-making on communication strategies. The underlying process of coping with complexity in evolving CBRN terrorism crises can be described as a continuous, dynamic process that can best be explained with a combination of traditional and more modern crisis communication approaches. Strategy-making in crisis situations by communication experts is still largely a black box. In this study, a novel approach of decomposing strategy-making by observing a table-top discussion is chosen to clarify the process. By identifying the core elements involved, a more detailed picture of communication strategy-making is created, thus promoting preparedness and professional resilience in the field.

  7. Experiences and Motives of Australian Single Mothers by Choice Who Make Early Contact with their Child's Donor Relatives.

    Kelly, Fiona J; Dempsey, Deborah J

    2017-01-30

    An increasing number of Australian parents of donor-conceived children are making contact with their child's donor relatives prior to their child reaching the age of majority. This process, often referred to as 'donor linking', can be achieved in Australia through either formal or informal mechanisms. Formal mechanisms exist in three states, each of which has legislation enabling donor linking in certain circumstances. Donor linking may also be achieved through informal mechanisms, such as online donor registries, social media searches, direct-to-consumer genetic testing, and fertility clinics which act as intermediaries between donors and recipients. Drawing on qualitative interview data, this article explores the donor linking practices of twenty-five single women who conceived using donated gametes. The findings suggest that early contact with donors is extremely popular among single women and that, even when formal legislative mechanisms are available, informal linking remains common. © The Author 2017. Published by Oxford University Press.

  8. Experiences and Motives of Australian Single Mothers by Choice who make Early Contact with their Child’s Donor Relatives

    Dempsey, Deborah J

    2016-01-01

    Abstract An increasing number of Australian parents of donor-conceived children are making contact with their child’s donor relatives prior to their child reaching the age of majority. This process, often referred to as ‘donor linking’, can be achieved in Australia through either formal or informal mechanisms. Formal mechanisms exist in three states, each of which has legislation enabling donor linking in certain circumstances. Donor linking may also be achieved through informal mechanisms, such as online donor registries, social media searches, direct-to-consumer genetic testing, and fertility clinics which act as intermediaries between donors and recipients. Drawing on qualitative interview data, this article explores the donor linking practices of twenty-five single women who conceived using donated gametes. The findings suggest that early contact with donors is extremely popular among single women and that, even when formal legislative mechanisms are available, informal linking remains common. PMID:28137771

  9. The Influence of Religiosity and Spirituality on Rural Parents' Health Decision Making and Human Papillomavirus Vaccine Choices.

    Thomas, Tami; Blumling, Amy; Delaney, Augustina

    2015-01-01

    General health implications of religiosity and spirituality on health have been associated with health promotion, so the purpose of this study was to examine the influence of religiosity and spirituality on rural parents' decision making to vaccinate their children against human papillomavirus (HPV). The associations of religiosity and spirituality with parental HPV vaccine decisions were examined in a sample of parents residing in small rural communities (N = 37). Parents of children aged 9 to 13 years participated in focus groups held in rural community contexts. Religiosity (i.e., participation in religious social structures) was a recurring and important theme when discussing HPV vaccination. Spirituality (i.e., subjective commitment to spiritual or religious beliefs) was found to influence the ways in which parents perceived their control over and coping with health issues potentially related to HPV vaccination. Together, religiosity and spirituality were found to play integral roles in these parents' lives and influenced their attitudes toward HPV vaccination uptake for their children.

  10. Influencing Eating Choices: Biological Food Cues in Advertising and Packaging Alter Trajectories of Decision Making and Behavior.

    Bailey, Rachel L

    2017-10-01

    From an ecological perception perspective (Gibson, 1977), the availability of perceptual information alters what behaviors are more and less likely at different times. This study examines how perceptual information delivered in food advertisements and packaging alters the time course of information processing and decision making. Participants categorized images of food that varied in information delivered in terms of color, glossiness, and texture (e.g., food cues) before and after being exposed to a set of advertisements that also varied in this way. In general, items with more direct cues enhanced appetitive motivational processes, especially if they were also advertised with direct food cues. Individuals also chose to eat products that were packaged with more available direct food cues compared to opaque packaging.

  11. Mental toughness latent profiles in endurance athletes.

    Joanna S Zeiger

    Full Text Available Mental toughness in endurance athletes, while an important factor for success, has been scarcely studied. An online survey was used to examine eight mental toughness factors in endurance athletes. The study aim was to determine mental toughness profiles via latent profile analysis in endurance athletes and whether associations exist between the latent profiles and demographics and sports characteristics. Endurance athletes >18 years of age were recruited via social media outlets (n = 1245, 53% female. Mental toughness was measured using the Sports Mental Toughness Questionnaire (SMTQ, Psychological Performance Inventory-Alternative (PPI-A, and self-esteem was measured using the Rosenberg Self-Esteem Scale (RSE. A three-class solution emerged, designated as high mental toughness (High MT, moderate mental toughness (Moderate MT and low mental toughness (Low MT. ANOVA tests showed significant differences between all three classes on all 8 factors derived from the SMTQ, PPI-A and the RSE. There was an increased odds of being in the High MT class compared to the Low MT class for males (OR = 1.99; 95% CI, 1.39, 2.83; P<0.001, athletes who were over 55 compared to those who were 18-34 (OR = 2.52; 95% CI, 1.37, 4.62; P<0.01, high sports satisfaction (OR = 8.17; 95% CI, 5.63, 11.87; P<0.001, and high division placement (OR = 2.18; 95% CI, 1.46,3.26; P<0.001. The data showed that mental toughness latent profiles exist in endurance athletes. High MT is associated with demographics and sports characteristics. Mental toughness screening in athletes may help direct practitioners with mental skills training.

  12. Choice & Consequence

    Khan, Azam

    to support hypothesis generation, hypothesis testing, and decision making. In addition to sensors in buildings, infrastructure, or the environment, we also propose the instrumentation of user interfaces to help measure performance in decision making applications. We show the benefits of applying principles...... between cause and effect in complex systems complicates decision making. To address this issue, we examine the central role that data-driven decision making could play in critical domains such as sustainability or medical treatment. We developed systems for exploratory data analysis and data visualization...... of data analysis and instructional interface design, to both simulation systems and decision support interfaces. We hope that projects such as these will help people to understand the link between their choices and the consequences of their decisions....

  13. Nudging and social marketing techniques encourage employees to make healthier food choices: a randomized controlled trial in 30 worksite cafeterias in The Netherlands.

    Velema, Elizabeth; Vyth, Ellis L; Hoekstra, Trynke; Steenhuis, Ingrid H M

    2018-02-01

    Currently, many studies focus on how the environment can be changed to encourage healthier eating behavior, referred to as choice architecture or "nudging." However, to date, these strategies are not often investigated in real-life settings, such as worksite cafeterias, or are only done so on a short-term basis. The objective of this study is to examine the effects of a healthy worksite cafeteria ["worksite cafeteria 2.0" (WC 2.0)] intervention on Dutch employees' purchase behavior over a 12-wk period. We conducted a randomized controlled trial in 30 worksite cafeterias. Worksite cafeterias were randomized to either the intervention or control group. The intervention aimed to encourage employees to make healthier food choices during their daily worksite cafeteria visits. The intervention consisted of 14 simultaneously executed strategies based on nudging and social marketing theories, involving product, price, placement, and promotion. Adjusted multilevel models showed significant positive effects of the intervention on purchases for 3 of the 7 studied product groups: healthier sandwiches, healthier cheese as a sandwich filling, and the inclusion of fruit. The increased sales of these healthier meal options were constant throughout the 12-wk intervention period. This study shows that the way worksite cafeterias offer products affects purchase behavior. Situated nudging and social marketing-based strategies are effective in promoting healthier choices and aim to remain effective over time. Some product groups only indicated an upward trend in purchases. Such an intervention could ultimately help prevent and reduce obesity in the Dutch working population. This trial was registered at the Dutch Trial Register (http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=5372) as NTR5372.

  14. Prospering in Tough Economic Times Through Loyal Customers

    Anderson Rolph

    2014-10-01

    Full Text Available In severe economic downturns, only a few business leaders have the courage and wisdom to invest in customer loyalty to increase profits instead of reflexively cutting costs to try to maintain falling profit margins. Moreover, the usual research and advice tends to focus on how companies can effectively and efficiently reduce costs in order to survive an economic decline. This study contributes to the literature by offering a fresh look at how best to respond in tough economic times by examining companies who have responded traditionally with cost cutting strategies versus companies who instead have invested in customer loyalty. We make the unique and contrarian argument that the latter strategy can be the superior business strategy, which underscores the originality of this investigation. Thus, the purpose of this study is to highlight why investing resources in creating and retaining loyal customers is the best strategy for companies to survive and prosper in tough economic conditions while simultaneously gaining longer-run competitive advantage. Based on quantitative and qualitative survey research methodology, the study findings identify and explain key customer loyalty measures, including: customization for customers, communication interactivity, nurturing of customers, commitment to customers, customer sharing networks, customer focused product assortments, facile exchanges, and customer engagement. Perceptive company executives will measure, benchmark, and regularly compare their performances on these key customer loyalty measures with different customer groups versus their company's past performances, managerial goals, and competitors, then make appropriate adjustments to retain their loyal customers and prosper during tough economic times.

  15. Fracture Toughness of Carbon Nanotube-Reinforced Metal- and Ceramic-Matrix Composites

    Chen, Y.L.; Liu, B.; Hwang, K.C.; Chen, Y.L.; Huang, Y.

    2011-01-01

    Hierarchical analysis of the fracture toughness enhancement of carbon nanotube- (CNT-) reinforced hard matrix composites is carried out on the basis of shear-lag theory and fracture mechanics. It is found that stronger CNT/matrix interfaces cannot definitely lead to the better fracture toughness of these composites, and the optimal interfacial chemical bond density is that making the failure mode just in the transition from CNT pull-out to CNT break. For hard matrix composites, the fracture toughness of composites with weak interfaces can be improved effectively by increasing the CNT length. However, for soft matrix composite, the fracture toughness improvement due to the reinforcing CNTs quickly becomes saturated with an increase in CNT length. The proposed theoretical model is also applicable to short fiber-reinforced composites.

  16. Fracture Toughness of Carbon Nanotube-Reinforced Metal- and Ceramic-Matrix Composites

    Y. L. Chen

    2011-01-01

    Full Text Available Hierarchical analysis of the fracture toughness enhancement of carbon nanotube- (CNT- reinforced hard matrix composites is carried out on the basis of shear-lag theory and facture mechanics. It is found that stronger CNT/matrix interfaces cannot definitely lead to the better fracture toughness of these composites, and the optimal interfacial chemical bond density is that making the failure mode just in the transition from CNT pull-out to CNT break. For hard matrix composites, the fracture toughness of composites with weak interfaces can be improved effectively by increasing the CNT length. However, for soft matrix composite, the fracture toughness improvement due to the reinforcing CNTs quickly becomes saturated with an increase in CNT length. The proposed theoretical model is also applicable to short fiber-reinforced composites.

  17. Does front-of-pack nutrition information improve consumer ability to make healthful choices? Performance of warnings and the traffic light system in a simulated shopping experiment.

    Machín, Leandro; Aschemann-Witzel, Jessica; Curutchet, María Rosa; Giménez, Ana; Ares, Gastón

    2018-02-01

    The inclusion of more attention-grabbing and easily interpretable front-of-pack (FOP) nutrition information is one of the public policies that can be implemented to empower consumers to identify unhealthful food products and to make more informed food choices. The aim of the present work was to evaluate the influence of two FOP nutrition labelling schemes - the traffic light labelling and the warning scheme - on consumer food purchases when facing a health goal. The study was conducted with 1182 people from Montevideo (Uruguay), recruited using a Facebook advertisement. Participants were randomly allocated to one of three between-subjects experimental conditions: (i) a control condition with no FOP nutrition information, (ii) FOP nutrition information using a modified version of the traffic light system including information about calorie, saturated fat, sugars and sodium content per portion, and (iii) FOP nutrition information using the Chilean warning system including separate signs for high calorie, saturated fat, sugars and sodium content. Respondents were asked to imagine that they had to purchase food in order to prepare a healthy dinner for themselves and their family, using the website of an online grocery store. Results showed that FOP nutrition information effectively improved the average healthfulness of participants' choices compared to the control condition, both in terms of the average nutritional composition of the purchased products and expenditure in specific product categories. No relevant differences between the effect of the traffic light and the warning system were found. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. New Min-Max Approach to Optimal Choice of the Weights in Multi-Criteria Group Decision-Making Problems

    Ming Chen

    2015-11-01

    Full Text Available In multi-criteria group decision-making (MCGDM, one of the most important problems is to determine the weights of criteria and experts. This paper intends to present two Min-Max models to optimize the point estimates of the weights. Since each expert generally possesses a uniform viewpoint on the importance (weighted value of each criterion when he/she needs to rank the alternatives, the objective function in the first model is to minimize the maximum variation between the actual score vector and the ideal one for all the alternatives such that the optimal weights of criteria are consistent in ranking all the alternatives for the same expert. The second model is designed to optimize the weights of experts such that the obtained overall evaluation for each alternative can collect the perspectives of the experts as many as possible. Thus, the objective function in the second model is to minimize the maximum variation between the actual vector of evaluations and the ideal one for all the experts, such that the optimal weights can reduce the difference among the experts in evaluating the same alternative. For the constructed Min-Max models, another focus in this paper is on the development of an efficient algorithm for the optimal weights. Some applications are employed to show the significance of the models and algorithm. From the numerical results, it is clear that the developed Min-Max models more effectively solve the MCGDM problems including the ones with incomplete score matrices, compared with the methods available in the literature. Specifically, by the proposed method, (1 the evaluation uniformity of each expert on the same criteria is guaranteed; (2 The overall evaluation for each alternative can collect the judgements of the experts as many as possible; (3 The highest discrimination degree of the alternatives is obtained.

  19. Fusion Power: A Strategic Choice for the Future Energy Provision. Why is So Much Time Wasted for Decision Making?

    D'haeseleer, William D.

    2005-01-01

    From a general analysis of the world energy issue, it is argued that an affordable, clean and reliable energy supply will have to consist of a portfolio of primary energy sources, a large fraction of which will be converted to a secondary carrier in large baseload plants. Because of all future uncertainties, it would be irresponsible not to include thermonuclear fusion as one of the future possibilities for electricity generation.The author tries to understand why nuclear-fusion research is not considered of strategic importance by the major world powers. The fusion programs of the USA and Europe are taken as prime examples to illustrate the 'hesitation'. Europe is now advocating a socalled 'fast-track' approach, thereby seemingly abandoning the 'classic' time frame towards fusion that it has projected for many years. The US 'oscillatory' attitude towards ITER in relation to its domestic program is a second case study that is looked at.From the real history of the ITER design and the 'siting' issue, one can try to understand how important fusion is considered by these world powers. Not words are important, but deeds. Fast tracks are nice to talk about, but timely decisions need to be taken and sufficient money is to be provided. More fundamental understanding of fusion plasma physics is important, but in the end, real hardware devices must be constructed to move along the path of power plant implementation.The author tries to make a balance of where fusion power research is at this moment, and where, according to his views, it should be going

  20. "We make choices we think are going to save us": Debate and stance identification for online breast cancer CAM discussions.

    Zhang, Shaodian; Qiu, Lin; Chen, Frank; Zhang, Weinan; Yu, Yong; Elhadad, Noémie

    2017-04-01

    Patients discuss complementary and alternative medicine (CAM) in online health communities. Sometimes, patients' conflicting opinions toward CAM-related issues trigger debates in the community. The objectives of this paper are to identify such debates, identify controversial CAM therapies in a popular online breast cancer community, as well as patients' stances towards them. To scale our analysis, we trained a set of classifiers. We first constructed a supervised classifier based on a long short-term memory neural network (LSTM) stacked over a convolutional neural network (CNN) to detect automatically CAM-related debates from a popular breast cancer forum. Members' stances in these debates were also identified by a CNN-based classifier. Finally, posts automatically flagged as debates by the classifier were analyzed to explore which specific CAM therapies trigger debates more often than others. Our methods are able to detect CAM debates with F score of 77%, and identify stances with F score of 70%. The debate classifier identified about 1/6 of all CAM-related posts as debate. About 60% of CAM-related debate posts represent the supportive stance toward CAM usage. Qualitative analysis shows that some specific therapies, such as Gerson therapy and usage of laetrile, trigger debates frequently among members of the breast cancer community. This study demonstrates that neural networks can effectively locate debates on usage and effectiveness of controversial CAM therapies, and can help make sense of patients' opinions on such issues under dispute. As to CAM for breast cancer, perceptions of their effectiveness vary among patients. Many of the specific therapies trigger debates frequently and are worth more exploration in future work.

  1. Patient centered decision making: use of conjoint analysis to determine risk-benefit trade-offs for preference sensitive treatment choices.

    Wilson, Leslie; Loucks, Aimee; Bui, Christine; Gipson, Greg; Zhong, Lixian; Schwartzburg, Amy; Crabtree, Elizabeth; Goodin, Douglas; Waubant, Emmanuelle; McCulloch, Charles

    2014-09-15

    Understanding patient preferences facilitates shared decision-making and focuses on patient-centered outcomes. Little is known about relapsing-remitting multiple sclerosis (RRMS) patient preferences for disease modifying therapies (DMTs). We use choice based conjoint (CBC) analysis to calculate patient preferences for risk/benefit trade-offs for hypothetical DMTs. Patients with RRMS were surveyed between 2012 and 2013. Our CBC survey mimicked the decision-making process and trade-offs of patients choosing DMTs, based on all possible DMT attributes. Mixed-effects logistic regression analyzed preferences. We estimated maximum acceptable risk trade-offs for various DMT benefits. Severe side-effect risks had the biggest impact on patient preference with a 1% risk, decreasing patient preference five-fold compared to no risk. (OR=0.22, pbenefit (OR=3.68, pbenefit trade-offs for attributes of all available DMTs. Evaluation of patient preferences is a key step in shared decision making and may significantly impact early drug initiation and compliance. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Enhancements to the TOUGH2 Simulator as Implemented in iTOUGH2

    Finsterle, Stefan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2015-03-01

    iTOUGH2 is a program for parameter estimation, sensitivity analysis, and uncertainty propagation analysis. It is based on the TOUGH2 simulator for non-isothermal multiphase, multicomponent flow and transport in fractured and porous media [Pruess, 1987, 1991, 2005, 2011; Falta et al., 1995; Pruess et al., 1999, 2002, 2012; Doughty, 2013]. The core of iTOUGH2 contains slightly modified versions of TOUGH2 modules. Most code modifications are editorial and do not affect the simulation results. As a result, standard TOUGH2 input files can be used in iTOUGH2, and identical results are obtained if iTOUGH2 is run in forward mode. However, a number of modifications have been made as described in this report. They enhance the functionality, flexibilitu, and eas-of-use of the forward simulator. This report complements the reports iTOUGH2 User's Guide, iTOUGH2 Command Referecne, and the collection of tutorial examples in iTOUGH2 Sample Problems.

  3. Resonant Cholinergic Dynamics in Cognitive and Motor Decision-Making: Attention, Category Learning, and Choice in Neocortex, Superior Colliculus, and Optic Tectum.

    Grossberg, Stephen; Palma, Jesse; Versace, Massimiliano

    2015-01-01

    Freely behaving organisms need to rapidly calibrate their perceptual, cognitive, and motor decisions based on continuously changing environmental conditions. These plastic changes include sharpening or broadening of cognitive and motor attention and learning to match the behavioral demands that are imposed by changing environmental statistics. This article proposes that a shared circuit design for such flexible decision-making is used in specific cognitive and motor circuits, and that both types of circuits use acetylcholine to modulate choice selectivity. Such task-sensitive control is proposed to control thalamocortical choice of the critical features that are cognitively attended and that are incorporated through learning into prototypes of visual recognition categories. A cholinergically-modulated process of vigilance control determines if a recognition category and its attended features are abstract (low vigilance) or concrete (high vigilance). Homologous neural mechanisms of cholinergic modulation are proposed to focus attention and learn a multimodal map within the deeper layers of superior colliculus. This map enables visual, auditory, and planned movement commands to compete for attention, leading to selection of a winning position that controls where the next saccadic eye movement will go. Such map learning may be viewed as a kind of attentive motor category learning. The article hereby explicates a link between attention, learning, and cholinergic modulation during decision making within both cognitive and motor systems. Homologs between the mammalian superior colliculus and the avian optic tectum lead to predictions about how multimodal map learning may occur in the mammalian and avian brain and how such learning may be modulated by acetycholine.

  4. Resonant cholinergic dynamics in cognitive and motor decision-making:Attention, category learning, and choice in neocortex, superior colliculus, and optic tectum

    Stephen eGrossberg

    2016-01-01

    Full Text Available Freely behaving organisms need to rapidly calibrate their perceptual, cognitive, and motor decisions based on continuously changing environmental conditions. These plastic changes include sharpening or broadening of cognitive and motor attention and learning to match the behavioral demands that are imposed by changing environmental statistics. This article proposes that a shared circuit design for such flexible decision-making is used in specific cognitive and motor circuits, and that both types of circuits use acetylcholine to modulate choice selectivity. Such task-sensitive control is proposed to control thalamocortical choice of the critical features that are cognitively attended and that are incorporated through learning into prototypes of visual recognition categories. A cholinergically-modulated process of vigilance control determines if a recognition category and its attended features are abstract (low vigilance or concrete (high vigilance. Homologous neural mechanisms of cholinergic modulation are proposed to focus attention and learn a multimodal map within the deeper layers of superior colliculus. This map enables visual, auditory, and planned movement commands to compete for attention, leading to selection of a winning position that controls where the next saccadic eye movement will go. Such map learning may be viewed as a kind of attentive motor category learning. The article hereby explicates a link between attention, learning, and cholinergic modulation during decision making within both cognitive and motor systems. Homologs between the mammalian superior colliculus and the avian optic tectum lead to predictions about how multimodal map learning may occur in the avian brain and how such learning may be modulated by acetycholine.

  5. ITOUGH2: Solving TOUGH inverse problems

    Finsterle, S.; Pruess, K. [Lawrence Berkeley Laboratory, CA (United States)

    1995-03-01

    ITOUGH2 is a program that provides inverse modeling capabilities for the TOUGH2 code. While the main purpose of ITOUGH2 is to estimate two-phase hydraulic properties of calibrating a TOUGH2 model to laboratory or field data, the information obtained by evaluating parameter sensitivities can also be used to optimize the design of an experiment, and to analyze the uncertainty of model predictions. ITOUGH2 has been applied to a number of laboratory and field experiments on different scales. Three examples are discussed in this paper, demonstrating the code`s capability to support test design, data analysis, and model predictions for a variety of TOUGH problems.

  6. Uncertainty Characterization of Reactor Vessel Fracture Toughness

    Li, Fei; Modarres, Mohammad

    2002-01-01

    To perform fracture mechanics analysis of reactor vessel, fracture toughness (K Ic ) at various temperatures would be necessary. In a best estimate approach, K Ic uncertainties resulting from both lack of sufficient knowledge and randomness in some of the variables of K Ic must be characterized. Although it may be argued that there is only one type of uncertainty, which is lack of perfect knowledge about the subject under study, as a matter of practice K Ic uncertainties can be divided into two types: aleatory and epistemic. Aleatory uncertainty is related to uncertainty that is very difficult to reduce, if not impossible; epistemic uncertainty, on the other hand, can be practically reduced. Distinction between aleatory and epistemic uncertainties facilitates decision-making under uncertainty and allows for proper propagation of uncertainties in the computation process. Typically, epistemic uncertainties representing, for example, parameters of a model are sampled (to generate a 'snapshot', single-value of the parameters), but the totality of aleatory uncertainties is carried through the calculation as available. In this paper a description of an approach to account for these two types of uncertainties associated with K Ic has been provided. (authors)

  7. Single specimen fracture toughness determination procedure using instrumented impact test

    Rintamaa, R.

    1993-04-01

    In the study a new single specimen test method and testing facility for evaluating dynamic fracture toughness has been developed. The method is based on the application of a new pendulum type instrumented impact tester equipped with and optical crack mouth opening displacement (COD) extensometer. The fracture toughness measurement technique uses the Double Displacement Ratio (DDR) method, which is based on the assumption that the specimen is deformed as two rigid arms that rotate around an apparent centre of rotation. This apparent moves as the crack grows, and the ratio of COD versus specimen displacement changes. As a consequence the onset ductile crack initiation can be detected on the load-displacement curve. Thus, an energy-based fracture toughness can be calculated. In addition the testing apparatus can use specimens with the Double ligament size as compared with the standard Charpy specimen which makes the impact testing more appropriate from the fracture mechanics point of view. The novel features of the testing facility and the feasibility of the new DDR method has been verified by performing an extensive experimental and analytical study. (99 refs., 91 figs., 27 tabs.)

  8. Emotions & Relationships: Dealing with the Tough Stuff

    Emotions & Relationships: Dealing with the Tough Stuff; emotional health; emotional health; emotional health article; emotional health articles; best way to deal with emotions; best ways to deal with relationships; how to build relationships; how to strengthen relationships

  9. Fracture toughness in metal matrix composites

    Perez Ipiña J.E.

    2000-01-01

    Full Text Available Evaluations of the fracture toughness in metal matrix composites (Duralcan reinforced with 15% of Al(20(3 and SiC are presented in this work. The application of Elastic Plastic Fracture Mechanics is discussed and the obtained values are compared with the ones obtained by means of Linear Elastic Fracture Mechanics. Results show that J IC derived K JC values are higher than the corresponding values obtained by direct application of the linear elastic methodology. The effect of a heat treatment on the material fracture toughness was also evaluated in which the analyzed approaches showed, not only different toughness values, but also opposite tendencies. A second comparison of the J IC and K JC values obtained in this work with toughness values reported in the literature is presented and discussed.

  10. Use of TOUGH2 on small computers

    Antunez, E.; Pruess, K.; Moridis, G. [Lawrence Berkeley Laboratory, CA (United States)

    1995-03-01

    TOUGH2/PC has been tested extensively on different PC platforms (486-33, 486-66, Pentium-90), with encouraging results. TOUGH2 performance has also been tested in other 32-bit computers as the MacIntosh Quadra 800, and a workstation IBM RISC 6000. Results obtained with these machines are compared with PCs` performance. PC results for 3-D geothermal reservoir models are discussed, including: (a) a Cartesian; and (b) a geothermal reservoir model with 1,411 irregular grid blocks. Also discussed are the results of the TOUGH2-compiler performance tests conducted on small computer systems. Code modifications required to operate on 32-bit computers and its setup in each machine environment are described. It is concluded that in today`s market PCs provide the best price/performance alternative to conduct TOUGH2 numerical simulations.

  11. Master curve based correlation between static initiation toughness KIC and crack arrest toughness KIa

    Wallin, K.; Rintamaa, R.

    1999-01-01

    Historically the ASME reference curve concept assumes a constant relation between static fracture toughness initiation toughness and crack arrest toughness. In reality, this is not the case. Experimental results show that the difference between K IC and K Ia is material specific. For some materials there is a big difference while for others they nearly coincide. So far, however, no systematic study regarding a possible correlation between the two parameters has been performed. The recent Master curve method, developed for brittle fracture initiation estimation, has enabled a consistent analysis of fracture initiation toughness data. The Master curve method has been modified to be able to describe also crack arrest toughness. Here, this modified 'crack arrest master curve' is further validated and used to develop a simple, but yet (for safety assessment purpose) adequately accurate correlation between the two fracture toughness parameters. The correlation enables the estimation of crack arrest toughness from small Charpy-sized static fracture toughness tests. The correlation is valid for low Nickel steels ≤ (1.2% Ni). If a more accurate description of the crack arrest toughness is required, it can either be measured experimentally or estimated from instrumented Charpy-V crack arrest load information. (orig.)

  12. Influence of heat treatment on the strength and fracture toughness of 7N01 aluminum alloy

    Li, Bo [School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, 610031, Sichuan (China); Wang, Xiaomin, E-mail: xmwang991011@163.com [School of Life Science and Engineering, Southwest Jiaotong University, Chengdu, 610031, Sichuan (China); Chen, Hui; Hu, Jie [School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, 610031, Sichuan (China); Huang, Cui [School of Life Science and Engineering, Southwest Jiaotong University, Chengdu, 610031, Sichuan (China); Gou, Guoqing [School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu, 610031, Sichuan (China)

    2016-09-05

    7N01 aluminum (Al) alloys are treated by five heat treatment methods as peak aging (T6), over aging (T74), high temperature and subsequently low temperature aging (HLA), retrogression and reaging (RRA) and double retrogression and reaging (DRRA). The strength and fracture toughness of the five samples are tested, and the microstructures are investigated by optical microscopy (OM), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The results show that 7N01 Al-alloy treated at T6 condition has high strength but low fracture toughness. Compared with T6 treatment, T74 and HLA treatments increase the fracture toughness by 67% and 90% respectively, while the strength decrease by 9% and 17%. RRA process is a proper treatment method for 7N01 which improves the fracture toughness without sacrificing strength. The fracture toughness of DRRA treated alloy is much lower than that of RRA. Quantitative analysis through TEM images shows that the heat treatment affects the mechanical properties of 7N01 Al-alloy highly through changing the precipitates in grains and on grain boundaries, which can be explained by the coherency strengthening mechanism and Orowan mechanism. - Highlights: • Five heat treatments which can change the properties of 7N01 Al alloy were designed. • Quantitative analysis of precipitates was employed to study the mechanism. • RRA treatment can make proper strength/toughness property balances for 7N01 Al alloy.

  13. Influence of heat treatment on the strength and fracture toughness of 7N01 aluminum alloy

    Li, Bo; Wang, Xiaomin; Chen, Hui; Hu, Jie; Huang, Cui; Gou, Guoqing

    2016-01-01

    7N01 aluminum (Al) alloys are treated by five heat treatment methods as peak aging (T6), over aging (T74), high temperature and subsequently low temperature aging (HLA), retrogression and reaging (RRA) and double retrogression and reaging (DRRA). The strength and fracture toughness of the five samples are tested, and the microstructures are investigated by optical microscopy (OM), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The results show that 7N01 Al-alloy treated at T6 condition has high strength but low fracture toughness. Compared with T6 treatment, T74 and HLA treatments increase the fracture toughness by 67% and 90% respectively, while the strength decrease by 9% and 17%. RRA process is a proper treatment method for 7N01 which improves the fracture toughness without sacrificing strength. The fracture toughness of DRRA treated alloy is much lower than that of RRA. Quantitative analysis through TEM images shows that the heat treatment affects the mechanical properties of 7N01 Al-alloy highly through changing the precipitates in grains and on grain boundaries, which can be explained by the coherency strengthening mechanism and Orowan mechanism. - Highlights: • Five heat treatments which can change the properties of 7N01 Al alloy were designed. • Quantitative analysis of precipitates was employed to study the mechanism. • RRA treatment can make proper strength/toughness property balances for 7N01 Al alloy.

  14. Fracture toughness of zirconia ceramic crowns made by feather-edge tooth preparation design

    Mirković Nemanja

    2012-01-01

    Full Text Available Background/Aim. Fracture toughness determines functional crown strenght and prevents damages on ceramics during mastication. There is a lack of relevant literature data about fracture toughness of crowns made by feather-edge preparation. Mechanical testing of ceramic samples is supposed to show if feather-edge tooth preparation is a successful method for making ceramic crowns without any risk of reduction of their mechanical properties. This research was done to establish effects of feather-edge tooth preparation on fracture toughness of single zirconia ceramic crowns. Methods. The research was performed as an experimental study. Sixty (60 ceramic crowns were made on non-carious extracted human premolars. Thirty (30 crowns were made on the basis of feather-edge preparation (experimental group I. The group II included 30 crowns made on 1 mm rounded shoulder. Crowns fabrication was executed on a copy mill production system “Zirkonzahn” (Zirkonzahn GMBH, Gais, Germany. The spherical compression test was used to determine fracture toughness, using 6 mm diameter ceramic ball. Fracture load for damaging ceramic crown was recorded on a universal testing machine - Zwick, type 1464, with the speed of 0.05 mm/min. Results. The results of this research introduced significant differences between fracture toughness of ceramic samples in every examined group. However, fracture toughness of crowns from both group was above 2 000 N, what was double beyond a recommended value. The mean value of fracture toughness in the feather-edge group was 2 090 N, and in shoulder group it was 2 214 N. Conclusion. This research showed a high fracture toughness of zirconia crowns made on feather-edge preparation. The examined crowns showed a fracture resistance at a sufficient distance in relation to the minimum values of functional loads. Further research of functional loads of these crown is necessary, as well as research of marginal adaptation of cemented crowns and

  15. Review of experimental studies in social psychology of small groups when an optimal choice exists and application to operating room management decision-making.

    Prahl, Andrew; Dexter, Franklin; Braun, Michael T; Van Swol, Lyn

    2013-11-01

    Because operating room (OR) management decisions with optimal choices are made with ubiquitous biases, decisions are improved with decision-support systems. We reviewed experimental social-psychology studies to explore what an OR leader can do when working with stakeholders lacking interest in learning the OR management science but expressing opinions about decisions, nonetheless. We considered shared information to include the rules-of-thumb (heuristics) that make intuitive sense and often seem "close enough" (e.g., staffing is planned based on the average workload). We considered unshared information to include the relevant mathematics (e.g., staffing calculations). Multiple studies have shown that group discussions focus more on shared than unshared information. Quality decisions are more likely when all group participants share knowledge (e.g., have taken a course in OR management science). Several biases in OR management are caused by humans' limited abilities to estimate tails of probability distributions in their heads. Groups are more susceptible to analogous biases than are educated individuals. Since optimal solutions are not demonstrable without groups sharing common language, only with education of most group members can a knowledgeable individual influence the group. The appropriate model of decision-making is autocratic, with information obtained from stakeholders. Although such decisions are good quality, the leaders often are disliked and the decisions considered unjust. In conclusion, leaders will find the most success if they do not bring OR management operational decisions to groups, but instead act autocratically while obtaining necessary information in 1:1 conversations. The only known route for the leader making such decisions to be considered likable and for the decisions to be considered fair is through colleagues and subordinates learning the management science.

  16. Constructing food choice decisions.

    Sobal, Jeffery; Bisogni, Carole A

    2009-12-01

    Food choice decisions are frequent, multifaceted, situational, dynamic, and complex and lead to food behaviors where people acquire, prepare, serve, give away, store, eat, and clean up. Many disciplines and fields examine decision making. Several classes of theories are applicable to food decision making, including social behavior, social facts, and social definition perspectives. Each offers some insights but also makes limiting assumptions that prevent fully explaining food choice decisions. We used constructionist social definition perspectives to inductively develop a food choice process model that organizes a broad scope of factors and dynamics involved in food behaviors. This food choice process model includes (1) life course events and experiences that establish a food choice trajectory through transitions, turning points, timing, and contexts; (2) influences on food choices that include cultural ideals, personal factors, resources, social factors, and present contexts; and (3) a personal system that develops food choice values, negotiates and balances values, classifies foods and situations, and forms/revises food choice strategies, scripts, and routines. The parts of the model dynamically interact to make food choice decisions leading to food behaviors. No single theory can fully explain decision making in food behavior. Multiple perspectives are needed, including constructionist thinking.

  17. Producers' Complex Risk Management Choices

    Pennings, J.M.E.; Isengildina, O.; Irwin, S.H.; Garcia, P.; Good, D.L.

    2008-01-01

    Producers have a wide variety of risk management instruments available, making their choice(s) complex. The way producers deal with this complexity can vary and may influence the impact that the determinants, such as risk aversion, have on their choices. A recently developed choice bracketing

  18. Fracture toughness of fibrous composite materials

    Poe, C. C., Jr.

    1984-01-01

    Laminates with various proportions of 0 deg, 45 deg, and 90 deg plies were fabricated from T300/5208 and T300/BP-907 graphite/epoxy prepreg tape material. The fracture toughness of each laminate orientation or lay-up was determined by testing center-cracked specimens, and it was also predicted with the general fracture-toughness parameter. The predictions were good except when crack-tip splitting was large, at which time the toughness and strengths tended to be underpredicted. By using predictions, a parametric study was also made of factors that influence fracture toughness. Fiber and matrix properties as well as lay-up were investigated. Without crack-tip splitting, fracture toughness increases in proportion to fiber strength and fiber volume fraction, increases linearly with E(22)/E(11), is largest when the modulus for non-0 deg fibers is greater than that of 0 deg fibers, and is smallest for 0(m)/90(p)(s) lay-ups. (The E(11) and E(22) are Young's moduli of the lamina parallel to and normal to the direction of the fibers, respectively). For a given proportion of 0 deg plies, the most notch-sensitive lay-ups are 0(m)/90(p)(s) and the least sensitive are 0(m)/45(n)(s) and alpha(s). Notch sensitivity increases with the proportion of 0 deg plies and decreases with alpha. Strong, tough matrix materials, which inhibit crack-tip splitting, generally lead to minimum fracture toughness.

  19. Deficient neural activity subserving decision-making during reward waiting time in intertemporal choice in adult attention-deficit hyperactivity disorder.

    Todokoro, Ayako; Tanaka, Saori C; Kawakubo, Yuki; Yahata, Noriaki; Ishii-Takahashi, Ayaka; Nishimura, Yukika; Kano, Yukiko; Ohtake, Fumio; Kasai, Kiyoto

    2018-04-24

    Impulsivity, which significantly affects social adaptation, is an important target behavioral characteristic in interventions for attention-deficit hyperactivity disorder (ADHD). Typically, people are willing to wait longer to acquire greater rewards. Impulsivity in ADHD may be associated with brain dysfunction in decision-making involving waiting behavior under such situations. We tested the hypothesis that brain circuitry during a period of waiting (i.e., prior to the acquisition of reward) is altered in adults with ADHD. The participants included 14 medication-free adults with ADHD and 16 healthy controls matched for age, sex, IQ, and handedness. The behavioral task had participants choose between a delayed, larger monetary reward and an immediate, smaller monetary reward, where the reward waiting time actually occurred during functional magnetic resonance imaging measurement. We tested for group differences in the contrast values of blood-oxygen-level dependent signals associated with the length of waiting time, calculated using the parametric modulation method. While the two groups did not differ in the time discounting rate, the delay-sensitive contrast values were significantly lower in the caudate and visual cortex in individuals with ADHD. The higher impulsivity scores were significantly associated with lower delay-sensitive contrast values in the caudate and visual cortex. These results suggest that deficient neural activity affects decision-making involving reward waiting time during intertemporal choice tasks, and provide an explanation for the basis of impulsivity in adult ADHD. © 2018 The Author. Psychiatry and Clinical Neurosciences © 2018 Japanese Society of Psychiatry and Neurology.

  20. Linking neuroscientific research on decision making to the educational context of novice students assigned to a multiple-choice scientific task involving common misconceptions about electrical circuits

    Patrice ePotvin

    2014-01-01

    Full Text Available Functional magnetic resonance imaging was used to identify the brain-based mechanisms of uncertainty and certainty associated with answers to multiple-choice questions involving common misconceptions about electric circuits. Twenty-two (22 scientifically novice participants (humanities and arts college students were asked, in an fMRI study, whether or not they thought the light bulbs in images presenting electric circuits were lighted up correctly, and if they were certain or uncertain of their answers. When participants reported that they were unsure of their responses, analyses revealed significant activations in brain areas typically involved in uncertainty (anterior cingulate cortex, anterior insula cortex, and superior/dorsomedial frontal cortex and in the left middle/superior temporal lobe. Certainty was associated with large bilateral activations in the occipital and parietal regions usually involved in visuospatial processing. Correct-and-certain answers were associated with activations that suggest a stronger mobilization of visual attention resources when compared to incorrect-and-certain answers. These findings provide insights into brain-based mechanisms of uncertainty that are activated when common misconceptions, identified as such by science education research literature, interfere in decision making in a school-like task. We also discuss the implications of these results from an educational perspective.

  1. Mezzo-scopic Analysis of Fracture Toughness in Steels

    Miyata Takashi

    2002-01-01

    Full Text Available The cleavage fracture toughness of steels was mezzo-scopically analyzed on the basis of the statistical local fracture criterion approach. The statistical stress criterion at the crack tip region suggests that the cleavage fracture toughness in steels can be described as a function of the yield stress, the cleavage fracture stress, and other mechanical properties of the materials. Formulation of the cleavage fracture toughness was first examined through an investigation on correlation between the cleavage toughness and the cleavage fracture stress obtained in notched round bar specimens in accordance with the theoretical prediction. Then, the scatter of the toughness, specimen thickness effect on the toughness, deterioration of the toughness due to cold working and irradiation, and improvement of the toughness caused by the Ni addition, were analyzed through the formulation of the toughness.

  2. Application of tan h curve fitting to toughness data

    Sakai, Yuzuru; Ogura, Nobukazu

    1985-01-01

    Curve-fitting regression procedures for toughness data have been examined. The objectives of fitting curve in the context of the study of nuclear pressure vessel steels are (1) convenient summarization of test data to permit comparison of materials and testing methods; (2) development of statistical base concerning the data; (3) the surveying of the relationships between charpy data and fracture toughness data; (4) estimation of fracture toughness level from charpy absorbed energy data. The computational procedures using the tanh function have been applied to the toughness data (charpy absorbed energy, static fracture toughness, dynamic fracture toughness, crack arrest toughness) of A533B cl.1 and A508 cl.3 steels. The results of the analysis shows the statistical features of the material toughness and gives the method for estimating fracture toughness level from charpy absorbed energy data. (author)

  3. Menopause as a long-term risk to health: implications of general practitioner accounts of prevention for women's choice and decision-making.

    Murtagh, Madeleine J; Hepworth, Julie

    2003-03-01

    Over the past two decades medical researchers and modernist feminist researchers have contested the meaning of menopause. In this article we examine various meanings of menopause in major medical and feminist literature and the construction of menopause in a semi-structured interview study of general practitioners in rural South Australia. Three discursive themes are identified in these interviews; (i) .the hormonal menopause - symptoms, risk, prevention; (ii). the informed menopausal woman; and (iii). decision-making and hormone replacement therapy. By using the discourse of prevention, general practitioners construct menopause in relation to women's health care choices, empowerment and autonomy. We argue that the ways in which these concepts are deployed by general practitioners in this study produces and constrains the options available to women. The implications of these general practitioner accounts are discussed in relation to the proposition that medical and feminist descriptions of menopause posit alternative but equally-fixed truths about menopause and their relationship with the range of responses available to women at menopause. Social and cultural explanations of disease causality (c.f. Germov 1998, Hardey 1998) are absent from the new menopause despite their being an integral part of the framework of the women's health movement and health promotion drawn on by these general practitioners. Further, the shift of responsibility for health to the individual woman reinforces practice claims to empower women, but oversimplifies power relations and constructs menopause as a site of self-surveillance. The use of concepts from the women's health movement and health promotion have nevertheless created change in both the positioning of women as having 'choices' and the positioning of some general practitioners in terms of greater information provision to women and an attention to the woman's autonomy. In conclusion, we propose that a new menopause has evolved

  4. Assessment of fracture toughness of structural steels

    Gomes Junyor, José Onésimo; Faria, Stéfanno Bruno; Rocha, Nirlando Antônio; Reis, Emil; Vilela, Jefferson José, E-mail: ze_onezo@hotmail.com, E-mail: sbrunofaria@gmail.com, E-mail: nar@cdtn.br, E-mail: emilr@cdtn.br, E-mail: jjv@cdtn.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil); Centro Universitário de Belo Horizonte (UNIBH), MG (Brazil); Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2017-11-01

    The fracture toughness parameters are applied to estimate the lifetime of mechanical components and define the criteria of safe failure and tolerable damages. This information allows equipment to be used longer with a high degree of safety. These techniques are applied in the Leak-Before-Break (LBB) concept that is accepted for designing the piping system of the primary circuit of the pressurized water reactor (PWR). In this work, fracture toughness tests such as J{sub IC} and CTOD were performed on some structural steels. The fracture toughness parameters were determined using SE(B) and C(T) test specimens. The fracture toughness values for the same material varied according to the type specimen. The parameter δ{sub 1c} showed different values when it was calculated using the ASTM E1820 standard and using the BS 7448: Part 1 standard. These results indicate that procedures of these standards need to be improved. Two systems with different sensitivity in the force measurement were used that showed similar results for toughness fracture but the dispersion was different. (author)

  5. Rapid Thermal Processing to Enhance Steel Toughness.

    Judge, V K; Speer, J G; Clarke, K D; Findley, K O; Clarke, A J

    2018-01-11

    Quenching and Tempering (Q&T) has been utilized for decades to alter steel mechanical properties, particularly strength and toughness. While tempering typically increases toughness, a well-established phenomenon called tempered martensite embrittlement (TME) is known to occur during conventional Q&T. Here we show that short-time, rapid tempering can overcome TME to produce unprecedented property combinations that cannot be attained by conventional Q&T. Toughness is enhanced over 43% at a strength level of 1.7 GPa and strength is improved over 0.5 GPa at an impact toughness of 30 J. We also show that hardness and the tempering parameter (TP), developed by Holloman and Jaffe in 1945 and ubiquitous within the field, is insufficient for characterizing measured strengths, toughnesses, and microstructural conditions after rapid processing. Rapid tempering by energy-saving manufacturing processes like induction heating creates the opportunity for new Q&T steels for energy, defense, and transportation applications.

  6. Software qualification of selected TOUGH2 modules

    Wu, Y.S.; Ahlers, C.F.; Fraser, P.; Simmons, A.; Pruess, K.

    1996-10-01

    The purpose of this package of reports is to provide all software baseline documents necessary for the software qualification of the single-phase Gas (EOS1G), Effective Continuum Method (ECM), Saturated/Unsaturated Flow (EOS9), and Radionuclide Transport (T2R3D) modules of TOUGH2, a numerical simulation code for multi-dimensional coupled fluid and heat flow of multiphase, multicomponent fluid mixtures in porous and fractured media. This report contains the following sections: (1) Requirements Specification, (2) Design Description, (3) Software Validation Test Plan and Report, (4) Software User Documentation, and (5) Appendices. These sections comprise sequential parts of the Software Life Cycle, and are not intended to stand alone but should be used in conjunction with the TOUGH User's Guide (Pruess, 1987), TOUGH2--A General Purpose Numerical Simulator for Multiphase Fluid and Heat Flow (Pruess, 1991), and the above-referenced TOUGH2 software qualification document. The qualification package is complete with the attached Software Identification Form and executable source code for the single-phase Gas, Effective Continuum method, Saturated/Unsaturated Flow, and Radionuclide Transport modules of TOUGH2

  7. An Evaluation of the Value of Choice-Making Opportunities in Single-Operant Arrangements: Simple Fixed- and Progressive-Ratio Schedules

    Tiger, Jeffrey H.; Toussaint, Karen A.; Roath, Christopher T.

    2010-01-01

    The current study compared the effects of choice and no-choice reinforcement conditions on the task responding of 3 children with autism across 2 single-operant paradigm reinforcer assessments. The first assessment employed simple fixed-ratio (FR) schedules; the second used progressive-ratio (PR) schedules. The latter assessment identified the…

  8. Interlaminar fracture toughness for composite materials

    Lee, Kang Yong; Kwon, Soon Man

    1991-01-01

    The new equation of energy release rate for a double cantilever beam specimen is proposed within the framework of the higher order shear deformable plate theory. The interlaminar fracture toughnesses by present theory, ASTM round robin test method and acoustic emission method are compared for thermoset Graphite/Epoxy and thermoplastic AS4/PEEK composites. As a result, the interlaminar fracture toughness values by present theory show good agreement within 5% when compared with ones by ASTM method and it is shown that ones by acoustic emission method yield the lower values than ones by ASTM method. It is observed that the interlaminar fracture toughness of thermoplastic AS4/PEEK composite is about ten times larger than one of thermoset Graphite/Epoxy composite. (Author)

  9. TOUGH2-GRS version 1. User manual

    Navarro, Martin; Eckel, Jens

    2016-07-15

    TOUGH2 is a code for the simulation of multi-phase flow processes in porous media that has been developed by the Lawrence Berkeley National Laboratory, California, USA. Since 1991, GRS has been using the code for process analyses and safety assessments for deep geological repositories and has extended the code by several processes that are relevant for repository systems. The TOUGH2 source code that has been developed further by GRS is referred to as TOUGH2-GRS. The present report presents code version 1.1.g, which was developed in project UM13 A 03400 sponsored by the German Federal Ministry for the Environment, Nature Conservation, Building and Nuclear Safety (BMUB).

  10. Finite Element Simulation of Fracture Toughness Test

    Chu, Seok Jae; Liu, Cong Hao

    2013-01-01

    Finite element simulations of tensile tests were performed to determine the equivalent stress - equivalent plastic strain curves, critical equivalent stresses, and critical equivalent plastic strains. Then, the curves were used as inputs to finite element simulations of fracture toughness tests to determine the plane strain fracture toughness. The critical COD was taken as the COD when the equivalent plastic strain at the crack tip reached a critical value, and it was used as a crack growth criterion. The relationship between the critical COD and the critical equivalent plastic strain or the reduction of area was found. The relationship between the plane strain fracture toughness and the product of the critical equivalent stress and the critical equivalent plastic strain was also found

  11. TOUGH2 User's Guide Version 2

    Pruess, K.; Oldenburg, C.M.; Moridis, G.J.

    1999-01-01

    TOUGH2 is a numerical simulator for nonisothermal flows of multicomponent, multiphase fluids in one, two, and three-dimensional porous and fractured media. The chief applications for which TOUGH2 is designed are in geothermal reservoir engineering, nuclear waste disposal, environmental assessment and remediation, and unsaturated and saturated zone hydrology. TOUGH2 was first released to the public in 1991; the 1991 code was updated in 1994 when a set of preconditioned conjugate gradient solvers was added to allow a more efficient solution of large problems. The current Version 2.0 features several new fluid property modules and offers enhanced process modeling capabilities, such as coupled reservoir-wellbore flow, precipitation and dissolution effects, and multiphase diffusion. Numerous improvements in previously released modules have been made and new user features have been added, such as enhanced linear equation solvers, and writing of graphics files. The T2VOC module for three-phase flows of water, air and a volatile organic chemical (VOC), and the T2DM module for hydrodynamic dispersion in 2-D flow systems have been integrated into the overall structure of the code and are included in the Version 2.0 package. Data inputs are upwardly compatible with the previous version. Coding changes were generally kept to a minimum, and were only made as needed to achieve the additional functionalities desired. TOUGH2 is written in standard FORTRAN77 and can be run on any platform, such as workstations, PCs, Macintosh, mainframe and supercomputers, for which appropriate FORTRAN compilers are available. This report is a self-contained guide to application of TOUGH2 to subsurface flow problems. It gives a technical description of the TOUGH2 code, including a discussion of the physical processes modeled, and the mathematical and numerical methods used. Illustrative sample problems are presented along with detailed instructions for preparing input data

  12. Information needs and decision-making preferences of older women offered a choice between surgery and primary endocrine therapy for early breast cancer.

    Burton, Maria; Kilner, Karen; Wyld, Lynda; Lifford, Kate Joanna; Gordon, Frances; Allison, Annabel; Reed, Malcolm; Collins, Karen Anna

    2017-12-01

    To establish older women's (≥75 years) information preferences regarding 2 breast cancer treatment options: surgery plus adjuvant endocrine therapy versus primary endocrine therapy. To quantify women's preferences for the mode of information presentation and decision-making (DM) style. This was a UK multicentre survey of women, ≥75 years, who had been offered a choice between PET and surgery at diagnosis of breast cancer. A questionnaire was developed including 2 validated scales of decision regret and DM preferences. Questionnaires were sent to 247 women, and 101 were returned (response rate 41%). The median age of participants was 82 (range 75 to 99), with 58 having had surgery and 37 having PET. Practical details about the impact, safety, and efficacy of treatment were of most interest to participants. Of least interest were cosmetic outcomes after surgery. Information provided verbally by doctors and nurses, supported by booklets, was preferred. There was little interest in technology-based sources of information. There was equal preference for a patient- or doctor-centred DM style and lower preference for a shared DM style. The majority (74%) experienced their preferred DM style. Levels of decision regret were low (15.73, scale 0-100). Women strongly preferred face to face information. Written formats were also helpful but not computer-based resources. Information that was found helpful to women in the DM process was identified. The study demonstrates many women achieved their preferred DM style, with a preference for involvement, and expressed low levels of decision regret. Copyright © 2017 John Wiley & Sons, Ltd.

  13. The Fracture Toughness of Nuclear Graphites Grades

    Burchell, Timothy D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Erdman, III, Donald L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Lowden, Rick R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hunter, James A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hannel, Cara C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-04-01

    New measurements of graphite mode I critical stress intensity factor, KIc (commonly referred to as the fracture toughness) and the mode II critical shear stress intensity, KIIc, are reported and compared with prior data for KIc and KIIc. The new data are for graphite grades PCEA, IG-110 and 2114. Variations of KIc and acoustic emission (AE) data with graphite texture are reported and discussed. The Codes and Standards applications of fracture toughness, KIc, data are also discussed. A specified minimum value for nuclear graphite KIc is recommended.

  14. If You or Someone You Love is Very Ill...Ask Tough Questions

    If you or someone you love is very ill... ask tough questions* Ask Your Doctor... 1 Will you talk openly and candidly with me and my family ... make decisions about my care? 7 Will you still be available to me even when I’m ...

  15. Fracture toughness of Al-Cr alloys with minor additions

    Datta, S.; Banerjee, M.K.

    2000-01-01

    Fracture toughness behavior of aluminium chromium alloys with minor additions is studied to determine its relation with microstructure and ageing conditions. The effect of the minor additions on the fracture toughness property of the alloys is also studied. Fracture toughness of Al-Cr alloys has been improved by selected minor additions. Also, the fracture toughness of the investigated alloys is found to be sensitive to ageing conditions. (author)

  16. An Experimental Decision-Making Paradigm to Distinguish Guilt and Regret and Their Self-Regulating Function via Loss Averse Choice Behavior

    Wagner, Ullrich; Handke, Lisa; Dörfel, Denise; Walter, Henrik

    2012-01-01

    Both guilt and regret typically result from counterfactual evaluations of personal choices that caused a negative outcome and are thought to regulate human decisions by people’s motivation to avoid these emotions. Despite these similarities, studies asking people to describe typical situations of guilt and regret identified the social dimension as a fundamental distinguishing factor, showing that guilt but not regret specifically occurs for choices in interpersonal (social) contexts. However,...

  17. Evolution: Weevils Get Tough on Symbiotic Tyrosine.

    Dale, Colin

    2017-12-04

    Weevils, which represent one of the most diverse groups of terrestrial insects in nature, obtain a tough exoskeleton through the activity of an ancient bacterial symbiont with a tiny genome that serves as a factory for the production of tyrosine. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Veins improve fracture toughness of insect wings.

    Jan-Henning Dirks

    Full Text Available During the lifetime of a flying insect, its wings are subjected to mechanical forces and deformations for millions of cycles. Defects in the micrometre thin membranes or veins may reduce the insect's flight performance. How do insects prevent crack related material failure in their wings and what role does the characteristic vein pattern play? Fracture toughness is a parameter, which characterises a material's resistance to crack propagation. Our results show that, compared to other body parts, the hind wing membrane of the migratory locust S. gregaria itself is not exceptionally tough (1.04±0.25 MPa√m. However, the cross veins increase the wing's toughness by 50% by acting as barriers to crack propagation. Using fracture mechanics, we show that the morphological spacing of most wing veins matches the critical crack length of the material (1132 µm. This finding directly demonstrates how the biomechanical properties and the morphology of locust wings are functionally correlated in locusts, providing a mechanically 'optimal' solution with high toughness and low weight. The vein pattern found in insect wings thus might inspire the design of more durable and lightweight artificial 'venous' wings for micro-air-vehicles. Using the vein spacing as indicator, our approach might also provide a basis to estimate the wing properties of endangered or extinct insect species.

  19. Fracture toughness of manet II steel

    Gboneim, M.M.; Munz, D.

    1997-01-01

    High fracture toughness was evaluated according to the astm and chromium (9-12) martensitic steels combine high strength and toughness with good corrosion and oxidation resistance in a range of environments, and also show relatively high creep strength at intermediate temperatures. They therefore find applications in, for example, the offshore oil and gas production and chemical industries i pipe work and reaction vessels, and in high temperature steam plant in power generation systems. Recently, the use of these materials in the nuclear field was considered. They are candidates as tubing materials for breeder reactor steam generators and as structural materials for the first wall and blanket in fusion reactors. The effect of ageing on the tensile properties and fracture toughness of a 12 Cr-1 Mo-Nb-v steel, MANET II, was investigated in the present work. Tensile specimens and compact tension (CT) specimens were aged at 550 degree C for 1000 h. The japanese standards. Both microstructure and fracture surface were examined using optical and scanning electron microscopy (SEM). The results showed that ageing did not affect the tensile properties. However, the fracture toughness K Ic and the tearing modules T were reduced due to the ageing treatment. The results were discussed in the light of the chemical composition and the fracture surface morphology. 9 figs., 3 tabs

  20. Proceedings of the TOUGH Symposium 2009

    Moridis, George J.; Doughty, Christine; Finsterle, Stefan; Sonnenthal, Eric

    2009-10-01

    Welcome to the TOUGH Symposium 2009. Within this volume are the Symposium Program for eighty-nine papers to be presented in both oral and poster formats. The full papers are available as pdfs linked from the Symposium Program posted on the TOUGH Symposium 2009 website http://esd.lbl.gov/newsandevents/events/toughsymposium09/program.html Additional updated information including any changes to the Program will also be available at the website. The papers cover a wide range of application areas and reflect the continuing trend toward increased sophistication of the TOUGH codes. A CD containing the proceedings papers will be published immediately following the Symposium and sent to all participants. As in the prior Symposium, selected papers will be invited for submission to a number of journals for inclusion in Special Issues focused on applications and developments of the TOUGH codes. These journals include, Transport in Porous Media, Geothermics, Energy Conversion and Management, Journal of Nuclear Science and Technology, and the Vadose Zone Journal.

  1. Fracture toughness of stainless steel welds

    Mills, W.J.

    1985-11-01

    The effects of temperature, composition and weld-process variations on the fracture toughness behavior for Types 308 and 16-8-2 stainless steel (SS) welds were examined using the multiple-specimen J/sub R/-curve procedure. Fracture characteristics were found to be dependent on temperature and weld process but not on filler material. Gas-tungsten-arc (GTA) welds exhibited the highest fracture toughness, a shielded metal-arc (SMA) weld exhibited an intermediate toughness and submerged-arc (SA) welds yielded the lowest toughness. Minimum-expected fracture properties were defined from lower-bound J/sub c/ and tearing modulus values generated here and in previous studies. Fractographic examination revealed that microvoid coalescence was the operative fracture mechanism for all welds. Second phase particles of manganese silicide were found to be detrimental to the ductile fracture behavior because they separated from the matrix during the initial stages of plastic straining. In SA welds, the high density of inclusions resulting from silicon pickup from the flux promoted premature dimple rupture. The weld produced by the SMA process contained substantially less manganese silicide, while GTA welds contained no silicide inclusions. Delta ferrite particles present in all welds were substantially more resistant to local failure than the silicide phase. In welds containing little or no manganese silicide, delta ferrite particles initiated microvoid coalescence but only after extensive plastic straining

  2. 46 CFR 54.05-16 - Production toughness testing.

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Production toughness testing. 54.05-16 Section 54.05-16... Toughness Tests § 54.05-16 Production toughness testing. (a) For vessels of welded construction, production... welding procedures shall be the same as used in the fabrication of the vessel. From each test plate, one...

  3. The limit of strength and toughness of steel

    Guo, Zhen [Univ. of California, Berkeley, CA (United States)

    2001-12-01

    The ideal structural steel combines high strength with high fracture toughness. This dissertation discusses the governing principles of strength and toughness, along with the approaches that can be used to improve these properties and the inherent limits to how strong and tough a steel can be.

  4. More progress on tough graphs -- The Y2K report

    Bauer, D.; Broersma, Haitze J.; Schmeichel, E.

    2000-01-01

    We now know that not every $2$-tough graph is hamiltonian. In fact for every $\\epsilon > 0$, there exists a ($9/4 - \\epsilon$) - tough nontraceable graph. We continue our quadrennial survey of results that relate the toughness of a graph to its cycle structure.

  5. Can Food Stamps Do More to Improve Food Choices? An Economic Perspective--Higher Cost of Food in Some Areas May Affect Food Stamp Households' Ability To Make Healthy Food Choices

    Nord, Mark; Hopwood, Heather

    2007-01-01

    The cost of “enough food,” estimated from the amount that low- and medium-income households in a geographic area report needing to spend to just meet their food needs, differs substantially across States and among metropolitan areas. In areas with high food costs, many food-stamp recipients are likely to have inadequate food resources to support healthy food choices.

  6. The Alleged Importance of Being Tough, Really Tough

    Klee, Robert

    2008-11-01

    Christina Hoff Sommers and Sally Satel, a philosopher and a psychiatrist, now both policy analysts at the American Enterprise Institute, write in their recent book One Nation Under Therapy: How the Helping Culture Is Eroding Self-Reliance that empirically unsupported psychological theories ultimately descended from the cultural upheavals of the 1960s have slowly wormed their way into the educational and social scientific mainstream. These theories, the authors argue, promote a view of the human person as someone who is ‘too fragile for this world’, and in need of ceaseless counseling and coddling from the cradle to the grave. The case the authors make for their thesis is, I argue, uneven strong in specific cases, but weak and overwrought in many others. In the end, I argue, they misidentify the main cause of the increasing shallowness that, to a growing number of critics, is slowly infesting contemporary social science and education.

  7. User's Guide for TOUGH2-MP - A Massively Parallel Version of the TOUGH2 Code

    Earth Sciences Division; Zhang, Keni; Zhang, Keni; Wu, Yu-Shu; Pruess, Karsten

    2008-01-01

    TOUGH2-MP is a massively parallel (MP) version of the TOUGH2 code, designed for computationally efficient parallel simulation of isothermal and nonisothermal flows of multicomponent, multiphase fluids in one, two, and three-dimensional porous and fractured media. In recent years, computational requirements have become increasingly intensive in large or highly nonlinear problems for applications in areas such as radioactive waste disposal, CO2 geological sequestration, environmental assessment and remediation, reservoir engineering, and groundwater hydrology. The primary objective of developing the parallel-simulation capability is to significantly improve the computational performance of the TOUGH2 family of codes. The particular goal for the parallel simulator is to achieve orders-of-magnitude improvement in computational time for models with ever-increasing complexity. TOUGH2-MP is designed to perform parallel simulation on multi-CPU computational platforms. An earlier version of TOUGH2-MP (V1.0) was based on the TOUGH2 Version 1.4 with EOS3, EOS9, and T2R3D modules, a software previously qualified for applications in the Yucca Mountain project, and was designed for execution on CRAY T3E and IBM SP supercomputers. The current version of TOUGH2-MP (V2.0) includes all fluid property modules of the standard version TOUGH2 V2.0. It provides computationally efficient capabilities using supercomputers, Linux clusters, or multi-core PCs, and also offers many user-friendly features. The parallel simulator inherits all process capabilities from V2.0 together with additional capabilities for handling fractured media from V1.4. This report provides a quick starting guide on how to set up and run the TOUGH2-MP program for users with a basic knowledge of running the (standard) version TOUGH2 code. The report also gives a brief technical description of the code, including a discussion of parallel methodology, code structure, as well as mathematical and numerical methods used

  8. An Experimental Decision-Making Paradigm to Distinguish Guilt and Regret and Their Self-Regulating Function via Loss Averse Choice Behavior.

    Wagner, Ullrich; Handke, Lisa; Dörfel, Denise; Walter, Henrik

    2012-01-01

    Both guilt and regret typically result from counterfactual evaluations of personal choices that caused a negative outcome and are thought to regulate human decisions by people's motivation to avoid these emotions. Despite these similarities, studies asking people to describe typical situations of guilt and regret identified the social dimension as a fundamental distinguishing factor, showing that guilt but not regret specifically occurs for choices in interpersonal (social) contexts. However, an experimental paradigm to investigate this distinction systematically by inducing emotions of guilt and regret online is still missing. Here, extending existing procedures, we introduce such a paradigm, in which participants choose in each trial between two lotteries, with the outcome of the chosen lottery (gain or loss) being either assigned to themselves (intrapersonal trials) or to another person (interpersonal trials). After results of both the chosen and the unchosen lottery were shown, subjects rated how they felt about the outcome, including ratings of guilt and regret. Trait Guilt (TG) was determined for all participants in order to take their general inclination to experience guilt into account. Results confirmed that guilt but not regret specifically occurred in an interpersonal context. Percentages of loss averse choices (choosing the lottery with the lower possible monetary loss) were determined as indicators of regulation via guilt and regret avoidance. High TG scorers generally made more loss averse choices than low TG scorers, while trial-by-trial analyses showed that low TG scorers used their feelings of guilt more specifically to avoid the same emotional experience in subsequent choices. Our results confirm the social dimension as the critical factor distinguishing guilt from regret and identify TG as an important moderator determining the way in which guilt vs. regret can regulate their own occurrence by influencing choice strategies.

  9. An experimental decision-making paradigm to distinguish guilt and regret and their self-regulating function via loss-averse choice behavior

    Ullrich eWagner

    2012-10-01

    Full Text Available Both guilt and regret typically result from counterfactual evaluations of personal choices that caused a negative outcome and are thought to regulate human decisions by people’s motivation to avoid these emotions. Despite these similarities, studies asking people to describe typical situations of guilt and regret identified the social dimension as a fundamental distinguishing factor, showing that guilt but not regret specifically occurs for choices in interpersonal (social contexts. However, an experimental paradigm to investigate this distinction systematically by inducing emotions of guilt and regret online is still missing. Here, extending existing procedures, we introduce such a paradigm, in which participants choose in each trial between two lotteries, with the outcome of the chosen lottery (gain or loss being either assigned to themselves (intrapersonal trials or to another person (interpersonal trials. After results of both the chosen and the unchosen lottery were shown, subjects rated how they felt about the outcome, including ratings of guilt and regret. Trait Guilt (TG was determined for all participants in order to take their general inclination to experience guilt into account. Results confirmed that guilt but not regret specifically occurred in an interpersonal context. Percentages of loss averse choices (choosing the lottery with the lower possible monetary loss were determined as indicators of regulation via guilt and regret avoidance. High TG scorers generally made more loss averse choices than low TG scorers, while trial-by-trial analyses showed that low TG scorers used their feelings of guilt more specifically to avoid the same emotional experience in subsequent choices. Our results confirm the social dimension as the critical factor distinguishing guilt from regret and identify TG as an important moderator determining the way in which guilt vs. regret can regulate their own occurrence by influencing choice strategies.

  10. An Experimental Decision-Making Paradigm to Distinguish Guilt and Regret and Their Self-Regulating Function via Loss Averse Choice Behavior

    Wagner, Ullrich; Handke, Lisa; Dörfel, Denise; Walter, Henrik

    2012-01-01

    Both guilt and regret typically result from counterfactual evaluations of personal choices that caused a negative outcome and are thought to regulate human decisions by people’s motivation to avoid these emotions. Despite these similarities, studies asking people to describe typical situations of guilt and regret identified the social dimension as a fundamental distinguishing factor, showing that guilt but not regret specifically occurs for choices in interpersonal (social) contexts. However, an experimental paradigm to investigate this distinction systematically by inducing emotions of guilt and regret online is still missing. Here, extending existing procedures, we introduce such a paradigm, in which participants choose in each trial between two lotteries, with the outcome of the chosen lottery (gain or loss) being either assigned to themselves (intrapersonal trials) or to another person (interpersonal trials). After results of both the chosen and the unchosen lottery were shown, subjects rated how they felt about the outcome, including ratings of guilt and regret. Trait Guilt (TG) was determined for all participants in order to take their general inclination to experience guilt into account. Results confirmed that guilt but not regret specifically occurred in an interpersonal context. Percentages of loss averse choices (choosing the lottery with the lower possible monetary loss) were determined as indicators of regulation via guilt and regret avoidance. High TG scorers generally made more loss averse choices than low TG scorers, while trial-by-trial analyses showed that low TG scorers used their feelings of guilt more specifically to avoid the same emotional experience in subsequent choices. Our results confirm the social dimension as the critical factor distinguishing guilt from regret and identify TG as an important moderator determining the way in which guilt vs. regret can regulate their own occurrence by influencing choice strategies. PMID:23133433

  11. Choice-Making in Rendering Culture-Bound Elements in Literary Translation: A Case Study on the English Translation Of «????»

    Meihua, Song

    2014-01-01

    How to render culture-bound elements into a foreign language remains one of the most challenging tasks for all translators, especially, when the source text is a literary one. To retain the aesthetic effects and other stylistic features of importance, some argue that choice can be made from either domestication or foreignization with…

  12. Making Women the Subjects of the Abortion Debate: A Class Exercise that Moves beyond "Pro-Choice" and "Pro-Life"

    Crawley, Sara L.; Willman, Rebecca K.; Clark, Leisa; Walsh, Clare

    2009-01-01

    In this article, the authors describe a classroom exercise designed to put women (and children and men) back at the center of the abortion debate, avoiding the standard rhetoric and engaging reflection on how everyone might find common political goals among the so-called pro-life and pro-choice sides. The exercise the authors offer in this article…

  13. Determinants of Coverage Decisions in Health Insurance Marketplaces: Consumers' Decision-Making Abilities and the Amount of Information in Their Choice Environment

    Barnes, Andrew J; Hanoch, Yaniv; Rice, Thomas

    2015-01-01

    Objective To investigate the determinants and quality of coverage decisions among uninsured choosing plans in a hypothetical health insurance marketplace. Study Setting Two samples of uninsured individuals: one from an Internet-based sample comprised largely of young, healthy, tech-savvy individuals (n = 276), and the other from low-income, rural Virginians (n = 161). Study Design We assessed whether health insurance comprehension, numeracy, choice consistency, and the number of plan choices were associated with participants' ability to choose a cost-minimizing plan, given their expected health care needs (defined as choosing a plan costing no more than $500 in excess of the total estimated annual costs of the cheapest plan available). Data Collection Primary data were collected using an online questionnaire. Principal Findings Uninsured who were more numerate showed higher health insurance comprehension; those with more health insurance comprehension made choices of health insurance plans more consistent with their stated preferences; and those who made choices more concordant with their stated preferences were less likely to choose a plan that cost more than $500 in excess of the cheapest plan available. Conclusions Increasing health insurance comprehension and designing exchanges to facilitate plan comparison will be critical to ensuring the success of health insurance marketplaces. PMID:24779769

  14. Choice-making in facilitation of agricultural innovation platforms in different contexts in West Africa: experiences from Benin, Ghana and Mali

    Paassen, van A.; Klerkx, L.W.A.; Adjei-Nsiah, S.; Adu-Acheampong, R.; Ouologuem, B.; Zannou, E.; Vissoh, P.; Soumano, L.; Dembele, F.; Traore, M.

    2013-01-01

    Platforms provide an increased capacity for learning and coordinated innovation. The value of platforms for innovation is widely recognized, but more understanding is needed of the choices made in facilitation, to enable platforms to perform effectively within varying value chain contexts. This

  15. The toughness of cold worked 316 stainless steel at 20 degrees C

    Chipperfield, C G [UKAEA, RNPDL, Risley (United Kingdom)

    1977-07-01

    General Yielding Fracture Mechanics Concepts have been used to evaluate and compare thickness effects, J-integral estimation procedures and methods of crack detection in three point bend test pieces of prestrained 316 stainless steel. The results suggest that no thickness effects will exist in irradiated test pieces so long as the failure mode is one of ductile fracture. The choice of toughness parameter, whether fracture initiation be characterised in terms of the contour integral J or Crack Opening Displacement, appears to be relatively unimportant since both criteria appear to predict critical defect sizes of similar magnitude. Suitable crack monitoring procedures have been evaluated for subsequent irradiated tests, and it would appear that a direct current potential drop technique is the most sensitive for a given specimen geometry and toughness level. (author)

  16. Advanced Vadose Zone Simulations Using TOUGH

    Finsterle, S.; Doughty, C.; Kowalsky, M.B.; Moridis, G.J.; Pan,L.; Xu, T.; Zhang, Y.; Pruess, K.

    2007-02-01

    The vadose zone can be characterized as a complex subsurfacesystem in which intricate physical and biogeochemical processes occur inresponse to a variety of natural forcings and human activities. Thismakes it difficult to describe, understand, and predict the behavior ofthis specific subsurface system. The TOUGH nonisothermal multiphase flowsimulators are well-suited to perform advanced vadose zone studies. Theconceptual models underlying the TOUGH simulators are capable ofrepresenting features specific to the vadose zone, and of addressing avariety of coupled phenomena. Moreover, the simulators are integratedinto software tools that enable advanced data analysis, optimization, andsystem-level modeling. We discuss fundamental and computationalchallenges in simulating vadose zone processes, review recent advances inmodeling such systems, and demonstrate some capabilities of the TOUGHsuite of codes using illustrative examples.

  17. Postirradiation fracture toughness of Inconel X-750

    Mills, W.J.

    1983-01-01

    The effect of fast-neutron irradiation on the fracture toughness response of Inconel X-750 was characterized at 427 deg C using the J-R curve technique. Irradiation exposures ranging from 3 to 16 displacements per atom resulted in a reduction in Jsub(Ic) from 130 to 76 kJ/m 2 and a reduction in tearing modulus from 32 to 2.6. Postirradiation fractographic examination revealed that an intergranular fracture mechanism was dominant, in contrast to the extensive transgranular cracking mode found on unirradiated fracture surfaces. The enhanced intergranular failure observed after irradiation was caused by extensive heterogeneous slip in a matrix that was greatly strengthened by an irradiation-induced dislocation substructure. Specifically, intense planar slip bands impinged on the grain boundaries and generated large stress concentrations. Since the stress concentrations could not be relaxed by the hardened matrix, the grain boundaries 'unzipped' readily, resulting in the low toughness and tearing resistance. (author)

  18. Fracture toughness calculation using dynamic testing

    Perosanz, F. J.; Serrano, M.; Martinez, C.; Lapena, J.

    1998-01-01

    The most critical component of a Nuclear Power Station is the Reactor Pressure Vessel (RPV), due to safety and integrity requirements. The RPV is subjected to neutron radiation and this phenomenon lead to microstructural changes in the material and modifications in the mechanical properties. Due to this effects, it is necessary to assess the structural integrity of the RPV along the operational life through surveillance programs. The main objective of this surveillance programs is to determine the fracture toughness of the material. At present this objective is reached combining direct measures and prediction techniques. In this work, direct measures of fracture toughness using instrumented Charpy V impact testing are present using a CIEMAT development on analysis of results. (Author) 6 refs

  19. Developing Mental Toughness: Lessons from Paralympians

    Alexander J. Powell

    2017-08-01

    Full Text Available Mental toughness (MT is a key psychological variable related to perseverance and success in performance domains. MT and its development has been explored across a range of contexts and across different sports, but no research to date has examined MT in relation to Paralympic athletes. We sought to understand the lived-experiences of mentally tough Paralympians, aiming to conceptualize MT in a Paralympic context and investigate its development. Ten Paralympic athletes were interviewed using in-depth, semi-structured interviews. The verbatim transcripts of the interviews served as the data for an interpretative phenomenological analysis. Three broad themes and several subthemes emerged in conceptualizing Paralympian MT: characteristics (determination, defiance, pragmatic, optimistic, resilient, self-belief and independence and autonomy, cognitions (normalization, sense of escape, non-acceptance of constraints, influence perception and connection and cognitive strategies (rational thinking, goal setting, pain management and control. In understanding MT development, two broad themes and several subthemes emerged: formative experiences (challenge, classification, setbacks, critical incident, trauma and recovery, sustained commitment, development of mind-set and perspective during challenge, failure, and acceptance, and support and coping resources (social support and significant others, external shaping, social support, overcoming problems, social comparison and reflective practice. The findings suggest that Paralympians benefited from exposure to highly demanding situations in a supportive environment and this helped develop mentally tough characteristics and behaviors and individualized cognitive coping strategies. Our findings highlight the association between the adaptive development of personal characteristics by overcoming physical and mental setbacks over a sustained time period. Overall, the findings suggest that to develop mentally tough

  20. Developing Mental Toughness: Lessons from Paralympians.

    Powell, Alexander J; Myers, Tony D

    2017-01-01

    Mental toughness (MT) is a key psychological variable related to perseverance and success in performance domains. MT and its development has been explored across a range of contexts and across different sports, but no research to date has examined MT in relation to Paralympic athletes. We sought to understand the lived-experiences of mentally tough Paralympians, aiming to conceptualize MT in a Paralympic context and investigate its development. Ten Paralympic athletes were interviewed using in-depth, semi-structured interviews. The verbatim transcripts of the interviews served as the data for an interpretative phenomenological analysis. Three broad themes and several subthemes emerged in conceptualizing Paralympian MT: characteristics (determination, defiance, pragmatic, optimistic, resilient, self-belief and independence and autonomy), cognitions (normalization, sense of escape, non-acceptance of constraints, influence perception and connection) and cognitive strategies (rational thinking, goal setting, pain management and control). In understanding MT development, two broad themes and several subthemes emerged: formative experiences (challenge, classification, setbacks, critical incident, trauma and recovery, sustained commitment, development of mind-set and perspective during challenge, failure, and acceptance), and support and coping resources (social support and significant others, external shaping, social support, overcoming problems, social comparison and reflective practice). The findings suggest that Paralympians benefited from exposure to highly demanding situations in a supportive environment and this helped develop mentally tough characteristics and behaviors and individualized cognitive coping strategies. Our findings highlight the association between the adaptive development of personal characteristics by overcoming physical and mental setbacks over a sustained time period. Overall, the findings suggest that to develop mentally tough characteristics

  1. Fracture-toughness variations in Alloy 718

    Mills, W.J.; Blackburn, L.D.

    1983-04-01

    The effect of product-form variations within a single heat on the J Ic fracture toughness behavior of Alloy 718 was examined at 24, 427 and 538 degree C using the multiple-specimen J R -curve method. Three product forms (plate, round bar and upset forging) were tested in both the conventional and modified heat-treatment (CHT and MHT) conditions. In CHT material, the fracture toughness response was different for the three product forms -- plate having the highest toughness, bar the lowest. The MHT was found to improve the overall fracture resistance for each product form. In this condition, plate and forging had very similar toughness values, but J Ic levels for the bar were considerably lower. These results and WHC data previously reported for four other Alloy 718 heats were unalloyed statistically to establish minimum-expected J Ic values based on tolerance limits bracketing 90% of a total population at a 95% confidence level. Metallographic and fractographic examinations of the seven material lots were performed to relate key microstructural features and operative fracture mechanisms to macroscopic properties. Generally, coarse δ precipitates controlled fracture properties in CHT material by initiating secondary dimples that pre-empted growth of the primary dimples nucleated by broken carbide inclusions. The MHT dissolved the coarse δ particles and thereby suppressed secondary microvoid coalescence. This generally enhanced the fracture resistance of Alloy 718, except when alternate secondary fracture mechanism, such as channel fracture and dimple rupture at δ-phase remnants, prematurely interrupted primary microvoid growth. 25 refs., 12 figs., 12 tabs

  2. Characterizing the toughness of an epoxy resin after wet aging using compact tension specimens with non-uniform moisture content

    Quino, Gustavo; El Yagoubi, Jalal; Lubineau, Gilles

    2014-01-01

    Characterizing the change in toughness of polymers subjected to wet aging is challenging because of the heterogeneity of the testing samples. Indeed, as wet aging is guided by a diffusion/reaction process, compact tension samples (defined by the ASTM D5045 standard), which are relevant for toughness characterization but are somewhat thick, display a non-uniform moisture content over the bulk material. We define here a rigorous procedure to extract meaningful data from such tests. Our results showed that the relation between the moisture uptake of the whole sample and the measured toughness was not a meaningful material property. In fact, we found that the measured toughness depended on the locally varying moisture uptake over the cracking path. Here, we propose a post-processing technique that relies on a validated reaction/diffusion model to predict the three-dimensional moisture state of the epoxy. This makes identification of the variation in toughness with respect to the local moisture content possible. In addition, we analyze the fracture surface using micrography and roughness measurements. The observed variations in toughness are correlated with the roughness in the vicinity of the crack tip. © 2014 Elsevier Ltd. All rights rese.

  3. Characterizing the toughness of an epoxy resin after wet aging using compact tension specimens with non-uniform moisture content

    Quino, Gustavo

    2014-11-01

    Characterizing the change in toughness of polymers subjected to wet aging is challenging because of the heterogeneity of the testing samples. Indeed, as wet aging is guided by a diffusion/reaction process, compact tension samples (defined by the ASTM D5045 standard), which are relevant for toughness characterization but are somewhat thick, display a non-uniform moisture content over the bulk material. We define here a rigorous procedure to extract meaningful data from such tests. Our results showed that the relation between the moisture uptake of the whole sample and the measured toughness was not a meaningful material property. In fact, we found that the measured toughness depended on the locally varying moisture uptake over the cracking path. Here, we propose a post-processing technique that relies on a validated reaction/diffusion model to predict the three-dimensional moisture state of the epoxy. This makes identification of the variation in toughness with respect to the local moisture content possible. In addition, we analyze the fracture surface using micrography and roughness measurements. The observed variations in toughness are correlated with the roughness in the vicinity of the crack tip. © 2014 Elsevier Ltd. All rights rese.

  4. Dynamic fracture toughness testing of structural steels

    Debel, C.P.

    1978-01-01

    Two candidate test methods aimed at producing materials properties of interest in connection with crack arrest assessments are currently under evaluation. These methods and the significance of the results are described. The quasi-static as well as the dynamic fracture toughness of a plain C-Mn steel in the as-quenched and tempered condition have been examined at temperatures between -115 0 C and the ambient temperature. Wedge-loaded duplex DCB-specimens were used in dynamic tests. The crack extension velocity was measured using a surface deposited grid and a registration circuit based on TTL-electronics. The toughness transition-temperature at quasi-static loading rate is found to be low; but during dynamic crack-extension a substantial shift of the transition-region to higher temperatures is produced, and fast fracture was obtained even at ambient temperature. Even though the dynamic fracture toughness Ksub(ID) increases with temperature, it decreases with increasing crack-extension velocity at a given temperature and the rate of decrease with respect to crack-extension velocity seems to be independent of temperature. Ksub(ID) appears to be insensitive to heat treatments. Test results indicate insufficient load-train stiffness, and problems due to crack branching were encountered. (author)

  5. Fracture toughness determination in steam generator tubes

    Bergant M; Yawny, A; Perez Ipina, J

    2012-01-01

    The assessment of the structural integrity of steam generator tubes in nuclear power plants deserved increasing attention in the last years due to the negative impact related to their failures. In this context, elastic plastic fracture mechanics (EPFM) methodology appears as a potential tool for the analysis. The application of EPFM requires, necessarily, knowledge of two aspects, i.e., the driving force estimation in terms of an elastic plastic toughness parameter (e.g., J) and the experimental measurement of the fracture toughness of the material (e.g., the material J-resistance curve). The present work describes the development of a non standardized experimental technique aimed to determine J-resistance curves for steam generator tubes with circumferential through wall cracks. The tubes were made of Incoloy 800 (Ni: 30.0-35.0; Cr: 19.0-23.0; Fe: 35.5 min, % in weight). Due to its austenitic microstructure, this alloy shows very high toughness and is widely used in applications where a good corrosion resistance in aqueous environment or an excellent oxidation resistance in high temperature environment is required. Finally, a procedure for the structural integrity analysis of steam generator tubes with crack-like defects, based on a FAD diagram (Failure Assessment Diagram), is briefly described (author)

  6. Tough Blends of Polylactide and Castor Oil

    Robertson, Megan L.; Paxton, Jessica M.; Hillmyer, Marc A. (UMM)

    2012-10-10

    Poly(l-lactide) (PLLA) is a renewable resource polymer derived from plant sugars with several commercial applications. Broader implementation of the material is limited due to its inherent brittleness. We show that the addition of 5 wt % castor oil to PLLA significantly enhances the overall tensile toughness with minimal reductions in the modulus and no plasticization of the PLLA matrix. In addition, we used poly(ricinoleic acid)-PLLA diblock copolymers, synthesized entirely from renewable resources, as compatibilizers for the PLLA/castor oil blends. Ricinoleic acid, the majority fatty acid comprising castor oil, was polymerized through a lipase-catalyzed condensation reaction. The resulting polymers contained a hydroxyl end-group that was subsequently used to initiate the ring-opening polymerization of L-lactide. The binary PLLA/castor oil blend exhibited a tensile toughness seven times greater than neat PLLA. The addition of block copolymer allowed for control over the morphology of the blends, and even further improvement in the tensile toughness was realized - an order of magnitude larger than that of neat PLLA.

  7. Fracture toughness of irradiated stainless steel alloys

    Mills, W.J.

    1986-01-01

    The postirradiation fracture toughness responses of Types 316 and 304 stainless steel (SS) wrought products, cast CF8 SS and Type 308 SS weld deposit were characterized at 427 0 C using J/sub R/-curve techniques. Fast-neutron irradiation of these alloys caused an order of magnitude reduction in J/sub c/ and two orders of magnitude reduction in tearing modulus at neutron exposures above 10 dpa, where radiation-induced losses in toughness appeared to saturate. Saturation J/sub c/ values for the wrought materials ranged from 28 to 31 kJ/m 2 ; the weld exhibited a saturation level of 11 kJ/m 2 . Maximum allowable flaw sizes for highly irradiated stainless steel components stressed to 90% of the unirradiated yield strength are on the order of 3 cm for the wrought material and 1 cm for the weld. Electron fractographic examination revealed that irradiation displacement damage brought about a transition from ductile microvoid coalescence to channel fracture, associated with local separation along planar deformation bands. The lower saturation toughness value for the weld relative to that for the wrought products was attributed to local failure of ferrite particles ahead of the advancing crack which prematurely initiated channel fracture

  8. Tough blends of polylactide and castor oil.

    Robertson, Megan L; Paxton, Jessica M; Hillmyer, Marc A

    2011-09-01

    Poly(l-lactide) (PLLA) is a renewable resource polymer derived from plant sugars with several commercial applications. Broader implementation of the material is limited due to its inherent brittleness. We show that the addition of 5 wt % castor oil to PLLA significantly enhances the overall tensile toughness with minimal reductions in the modulus and no plasticization of the PLLA matrix. In addition, we used poly(ricinoleic acid)-PLLA diblock copolymers, synthesized entirely from renewable resources, as compatibilizers for the PLLA/castor oil blends. Ricinoleic acid, the majority fatty acid comprising castor oil, was polymerized through a lipase-catalyzed condensation reaction. The resulting polymers contained a hydroxyl end-group that was subsequently used to initiate the ring-opening polymerization of l-lactide. The binary PLLA/castor oil blend exhibited a tensile toughness seven times greater than neat PLLA. The addition of block copolymer allowed for control over the morphology of the blends, and even further improvement in the tensile toughness was realized-an order of magnitude larger than that of neat PLLA.

  9. FLEXURAL TOUGHNESS OF STEEL FIBER REINFORCED CONCRETE

    Fehmi ÇİVİCİ

    2006-02-01

    Full Text Available Fiber concrete is a composite material which has mechanical and physical characteristics unlike plain concrete. One of the important mechanical characteristics of fiber concrete is its energy absorbing capability. This characteristics which is also called toughness, is defined as the total area under the load-deflection curve. A number of composite characteristics such as crack resistance, ductility and impact resistance are related to the energy absorbtion capacity. According to ASTM C 1018 and JSCE SF-4 the calculation of toughness is determined by uniaxial flexural testing. Fiber concrete is often used in plates such as bridge decks, airport pavements, parking areas, subjected to cavitation and erosion. In this paper, toughness has been determined according to ASTM C 1018 and JSCE SF-4 methods by testing beam specimens. Energy absorbing capacities of plain and steel fiber reinforced concrete has been compared by evaluating the results of two methods. Also plain and steel fiber reinforced plate specimens behaviors subjected to biaxial flexure are compared by the loaddeflection curves of each specimen.

  10. LHC Report: A tough restart

    Jan Uythoven for the LHC team

    2012-01-01

    The third LHC Technical Stop of five days took place in the week of September 17. Getting back to normal operation after a technical stop  can sometimes be difficult, with debugging, testing and requalification required on the systems that have seen interventions. Folding in a selection of other problems can make for a frustrating time.   The new injector magnet is transported to the LHC. Photo: TE/ABT group. The restart experienced over the last days was one of the tougher ones. Many problems occurred, both small and large, one after the other; in the end it took until Sunday afternoon, 9 days after the end of the technical stop, to have a physics fill in the machine that delivered an initial luminosity similar to those before the technical stop. Most problems encountered were, in fact, not related to the technical stop. The technical stop consisted of the usual maintenance and consolidation of the various systems, but two items stand out: the replacement of the mirrors an...

  11. TOUGH2 modeling. Pre- and post processing; TOUGH2 Modellierungen. Prae- und Postprozessing

    Frieling, Gerd; Bracke, Guido

    2013-12-15

    GRS is modeling the two-phase flow in porous media using the program TOUGH2. The report describes the TOUGH2 program structure and the essential input parameters. Some of the important physical models are discussed for better understanding of the required data input. The data processing and visualization that is very specific for the GRS work flow Is described in detail. GRS has refined the standard modules EOS7 and EOS7R, the model extensions consider the rock convergence, time dependent boundary conditions and include the direction dependent diffusion or dispersion.

  12. The toughness of secondary cell wall and woody tissue

    Lucas, P. W.; Tan, H. T. W.; Cheng, P. Y.

    1997-01-01

    The 'across grain' toughness of 51 woods has been determined on thin wet sections using scissors. The moisture content of sections and the varying sharpness of the scissor blades had little effect on the results. In thin sections (less than 0.6mm), toughness rose linearly with section thickness. The intercept toughness at zero thickness, estimated from regression analysis, was proportional to relative density, consistent with values reported for non-woody plant tissues. Extrapolation of the i...

  13. Modifications and additions to selected TOUGH2 modules

    Wu, Y.S.; Mishra, A.K.

    1998-01-01

    The purpose of this report is to provide all software baseline documents necessary for the software qualification of the revised versions of the selected TOUGH2 modules, which include single-phase gas (EOS1G), effective continuum method (EOS3/ECM), saturated/unsaturated flow (EOS9), and radionuclide transport (T2R3D) modules of the TOUGH2 code. TOUGH2 is a numerical simulation code for multi-dimensional, coupled fluid and heat flow of multiphase, multicomponent fluid mixtures in porous and fractured media. This report augments the document Software Qualification of Selected TOUGH2 modules. This report contains the following sections: (1) requirement specifications and code development and (2) software validation test plan and results. These sections comprise sequential parts of Software Lifecycle, and should be used in conjunction with the TOUGH User's Guide, TOUGH2 documentation, TOUGH2 Software Qualification, and Software Qualification of Selected TOUGH2 modules. The version of TOUGH2 used with the software being qualified herein is the October 1996 Standard Version 1.2, as qualified in Wu et al. (1996) and housed at the Department of Energy's Energy Science and Technology Software Center (ESTSC) in Oak Ridge, Tennessee

  14. Effect of informational internet web pages on patients' decision-making: randomised controlled trial regarding choice of spinal or general anaesthesia for orthopaedic surgery.

    Groves, N D; Humphreys, H W; Williams, A J; Jones, A

    2010-03-01

    This study explored whether patients' preference for particular types of anaesthesia could be influenced pre-operatively by giving them the addresses of various relevant websites. Patients at an orthopaedic pre-assessment education clinic completed a questionnaire, which included a short multiple-choice general knowledge quiz about anaesthesia, and also questioned them as to their choice of anaesthesia (general or neuraxial). Patients were randomly assigned to intervention or control groups. Intervention group members were given the addresses of three relevant anaesthesia and health related websites to access at home. All patients were asked to complete the questionnaires on a second occasion, before surgery. Initially, most patients stated a preference for general anaesthesia. Subsequently, the intervention group altered their preference towards neuraxial anaesthesia compared to the control group (p < or = 0.0001). The increase in median (IQR [range]) anaesthesia knowledge test score was greater in the intervention group (from 10.0 (9.0-12.0 [5.0-14.0]) to 13.0 (11.0-14.0 [6.0-14.0])) than in the control group (from 10.0 (9.0-11.5 [3.0-13.0]) to 11.0 (9.0-12.0 [4.0-14.0]); p = 0.0068).

  15. A summary of the low upper shelf toughness safety margin issue

    Merkle, J.G.

    1991-01-01

    The low upper shelf toughness issue has a long history, beginning with the choice of materials for the submerged arc welding process, but also potentially involving the use of A302-B plate. Criteria for vessels containing low upper shelf materials have usually been expressed in terms of the Charpy upper shelf impact energy. Although these criteria have had several different bases, the range of limiting values for wall thicknesses approaching 229 mm (9 in.) has remained between 54 to 68J (40 to 50 ft lbs). Allowable values for vessels with thinner walls and/or only circumferential low upper shelf welds might conceivably be less. A decision on criteria to be incorporated into the ASME Code is now being made. Choices to be made concern the method for estimating the decrease in upper shelf impact energy, flaw geometry for circumferential welds, statistical significance of toughness values, the choice between J D and J M , reference pressure, safety factors and the inclusion of tearing stability calculations by means of R curve extrapolation. NRC research programs have contributed significantly to the resolution of the low upper shelf issue. These programs embrace all aspects of the issue, including material characterization, large scale testing, analysis and criteria development. 52 refs., 5 figs

  16. Understanding Toughness in Bioinspired Cellulose Nanofibril/Polymer Nanocomposites.

    Benítez, Alejandro J; Lossada, Francisco; Zhu, Baolei; Rudolph, Tobias; Walther, Andreas

    2016-07-11

    Cellulose nanofibrils (CNFs) are considered next generation, renewable reinforcements for sustainable, high-performance bioinspired nanocomposites uniting high stiffness, strength and toughness. However, the challenges associated with making well-defined CNF/polymer nanopaper hybrid structures with well-controlled polymer properties have so far hampered to deduce a quantitative picture of the mechanical properties space and deformation mechanisms, and limits the ability to tune and control the mechanical properties by rational design criteria. Here, we discuss detailed insights on how the thermo-mechanical properties of tailor-made copolymers govern the tensile properties in bioinspired CNF/polymer settings, hence at high fractions of reinforcements and under nanoconfinement conditions for the polymers. To this end, we synthesize a series of fully water-soluble and nonionic copolymers, whose glass transition temperatures (Tg) are varied from -60 to 130 °C. We demonstrate that well-defined polymer-coated core/shell nanofibrils form at intermediate stages and that well-defined nanopaper structures with tunable nanostructure arise. The systematic correlation between the thermal transitions in the (co)polymers, as well as its fraction, on the mechanical properties and deformation mechanisms of the nanocomposites is underscored by tensile tests, SEM imaging of fracture surfaces and dynamic mechanical analysis. An optimum toughness is obtained for copolymers with a Tg close to the testing temperature, where the soft phase possesses the best combination of high molecular mobility and cohesive strength. New deformation modes are activated for the toughest compositions. Our study establishes quantitative structure/property relationships in CNF/(co)polymer nanopapers and opens the design space for future, rational molecular engineering using reversible supramolecular bonds or covalent cross-linking.

  17. Making food labels social: The impact of colour of nutritional labels and injunctive norms on perceptions and choice of snack foods.

    Vasiljevic, Milica; Pechey, Rachel; Marteau, Theresa M

    2015-08-01

    Recent studies report that using green labels to denote healthier foods, and red to denote less healthy foods increases consumption of green- and decreases consumption of red-labelled foods. Other symbols (e.g. emoticons conveying normative approval and disapproval) could also be used to signal the healthiness and/or acceptability of consuming such products. The present study tested the combined effects of using emoticons and colours on labels amongst a nationally representative sample of the UK population (n = 955). In a 3 (emoticon expression: smiling vs. frowning vs. no emoticon) × 3 (colour label: green vs. red vs. white) ×2 (food option: chocolate bar vs. cereal bar) between-subjects experiment, participants rated the level of desirability, healthiness, tastiness, and calorific content of a snack bar they had been randomised to view. At the end they were further randomised to view one of nine possible combinations of colour and emoticon labels and asked to choose between a chocolate and a cereal bar. Regardless of label, participants rated the chocolate as tastier and more desirable when compared to the cereal bar, and the cereal bar as healthier than the chocolate bar. A series of interactions revealed that a frowning emoticon on a white background decreased perceptions of healthiness and tastiness of the cereal bar, but not the chocolate bar. In the explicit choice task selection was unaffected by label. Overall nutritional labels had limited effects on perceptions and no effects on choice of snack foods. Emoticon labels yielded stronger effects on perceptions of taste and healthiness of snacks than colour labels. Frowning emoticons may be more potent than smiling emoticons at influencing the perceived healthiness and tastiness of foods carrying health halos. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  18. Fracture toughness for materials of low ductility

    Barzilay, S.; Karp, B.; Perl, M.

    1998-05-01

    The results of a survey of methods for evaluating fracture toughness characteristics for semi-brittle and brittle materials are presented in this report. These methods differ considerably from those used for ductile materials by the specimen configurations, the methodology of the experiments and by the problems occurring while using these methods. The survey yields several important findings A. It is possible to create steady state crack growth by cyclic loading in several semi-brittle materials. B. The need for pre-cracking is not yet clear, nevertheless it is recommended to evaluate fracture toughens with pre-cracked specimen. C. As crack length and ligament size may effect fracture toughness results it is necessary to define minimum specimen dimensions to avoid this effect. D. The specimen thickness hardly affects the fracture toughens. E. Loading rate for the test is not well defined. It is commonly accepted to end the test in one minute. F. The main mechanism that causes inelastic deformation in semi-brittle materials is related to the generation of micro-cracks

  19. Models of expert assessments and their study in problems of choice and decision-making in management of motor transport processes

    Belokurov, V. P.; Belokurov, S. V.; Korablev, R. A.; Shtepa, A. A.

    2018-05-01

    The article deals with decision making concerning transport tasks on search iterations in the management of motor transport processes. An optimal selection of the best option for specific situations is suggested in the management of complex multi-criteria transport processes.

  20. Cascading of Biomass. 13 Solutions for a Sustainable Bio-based Economy. Making Better Choices for Use of Biomass Residues, By-products and Wastes

    Odegard, I.; Croezen, H.; Bergsma, G.

    2012-08-15

    Smarter and more efficient use of biomass, referred to as cascading, can lead to an almost 30% reduction in European greenhouse gas emissions by 2030 compared with 2010. As the title study makes clear, cascading of woody biomass, agricultural and industrial residues and other waste can make a significant contribution to a greening of the economy. With the thirteen options quantitatively examined annual emissions of between 330 and 400 Mt CO2 can be avoided by making more efficient use of the same volume of biomass as well as by other means. 75% of the potential CO2 gains can be achieved with just four options: (1) bio-ethanol from straw, for use as a chemical feedstock; (2) biogas from manure; (3) biorefining of grass; and (4) optimisation of paper recycling. Some of the options make multiple use of residues, with biomass being used to produce bioplastics that, after several rounds of recycling, are converted to heat and power at the end of their life, for example. In other cases higher-grade applications are envisaged: more efficient use of recyclable paper and wood waste, in both economic and ecological terms, using them as raw materials for new paper and chipboard rather than as an energy source. Finally, by using smart technologies biomass can be converted to multiple products.

  1. Empowering Parents: States Have a Role in Ensuring Parents Have the Data They Need to Make Informed Choices. Data for Action 2012

    Data Quality Campaign, 2012

    2012-01-01

    Accessible, tailored, and easy-to-understand data can help parents influence their children's learning, take advantage of school resources, and inform their educational decision making: (1) Information about their children--such as attendance, performance, progress, and expected outcomes; and (2) Information about their children's current school…

  2. 46 CFR 57.06-5 - Production toughness testing.

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Production toughness testing. 57.06-5 Section 57.06-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE ENGINEERING WELDING AND BRAZING Production Tests § 57.06-5 Production toughness testing. (a) In addition to the test specimens required by...

  3. Toughness of membranes applied in polymer electrolyte fuel cells

    Kiefer, J; Brack, H P; Scherer, G G [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1999-08-01

    Since several years we apply the radiation-grafting technique to prepare polymeric membranes for application in polymer electrolyte fuel cells (PEFCs). Our investigations presented here focus on changes in toughness of these materials after the various synthesis steps and the importance of membrane toughness for their application in PEFCs. (author) 2 figs., 4 refs.

  4. Shallow-crack toughness results for reactor pressure vessel steel

    Theiss, T.J.; Shum, D.K.M.; Rolfe, S.T.

    1992-01-01

    The Heavy Section Steel Technology Program (HSST) is investigating the influence of flaw depth on the fracture toughness of reactor pressure vessel (RPV) steel. To complete this investigation, techniques were developed to determine the fracture toughness from shallow-crack specimens. A total of 38 deep and shallow-crack tests have been performed on beam specimens about 100 mm deep loaded in 3-point bending. Two crack depths (a ∼ 50 and 9 mm) and three beam thicknesses (B ∼ 50, 100, and 150 mm) have been tested. Techniques were developed to estimate the toughness in terms of both the J-integral and crack-tip opening displacement (CTOD). Analytical J-integral results were consistent with experimental J-integral results, confirming the validity of the J-estimation schemes used and the effect of flaw depth on fracture toughness. Test results indicate a significant increase in the fracture toughness associated with the shallow flaw specimens in the lower transition region compared to the deep-crack fracture toughness. There is, however, little or no difference in toughness on the lower shelf where linear-elastic conditions exist for specimens with either deep or shallow flaws. The increase in shallow-flaw toughness compared with deep-flaw results appears to be well characterized by a temperature shift of 35 degree C

  5. Preface to the Special Issue on TOUGH Symposium 2015

    Blanco-Martín, Laura

    2017-11-01

    The TOUGH Symposium 2015 was held in Berkeley, California, September 28-30, 2015. The TOUGH family of codes, developed at the Energy Geosciences Division of Lawrence Berkeley National Laboratory (LBNL), is a suite of computer programs for the simulation of multiphase and multicomponent fluid and heat flows in porous and fractured media with applications in many geosciences fields, such as geothermal reservoir engineering, nuclear waste disposal, geological carbon sequestration, oil and gas reservoirs, gas hydrate research, vadose zone hydrology and environmental remediation. Since the first release in the 1980s, many modifications and enhancements have been continuously made to TOUGH and its various descendants (iTOUGH2, TOUGH+, TOUGH-MP, TOUGHREACT, TOUGH+HYDRATE, TMVOC...), at LBNL and elsewhere. Today, these codes are used worldwide in academia, government organizations and private companies in problems involving coupled hydrological, thermal, biogeochemical and geomechanical processes. The Symposia, organized every 2-3 years, bring together developers and users for an open exchange on recent code enhancements and applications. In 2015, the Symposium was attended by one hundred participants, representing thirty-four nationalities. This Special Issue in Computers & Geosciences gathers extended versions of selected Symposium proceedings related to (i) recent enhancements to the TOUGH family of codes and (ii) coupled flow and geomechanics processes modeling.

  6. A statistical study on fracture toughness data of Japanese RPVS

    Sakai, Y.; Ogura, N.

    1987-01-01

    In a cooperative study for investigating fracture toughness on pressure vessel steels produced in Japan, a number of heats of ASTM A533B cl.1 and A508 cl.3 steels have been studied. Approximately 3000 fracture toughness data and 8000 mechanical properties data were obtained and filed in a computer data bank. Statistical characterization of toughness data in the transition region has been carried out using the computer data bank. Curve fitting technique for toughness data has been examined. Approach using the function to model the transition behaviours of each toughness has been applied. The aims of fitting curve technique were as follows; (1) Summarization of an enormous toughness data base to permit comparison heats, materials and testing methods; (2) Investigating the relationships among static, dynamic and arrest toughness; (3) Examining the ASME K(IR) curve statistically. The methodology used in this study for analyzing a large quantity of fracture toughness data was found to be useful for formulating a statistically based K(IR) curve. (orig./HP)

  7. On the Evolutionary Stability of 'Tough' Bargaining Behavior

    Poulsen, Anders

    2003-01-01

    This paper investigates whether 'tough' bargaining behavior, which gives rise to inefficiency, can be evolutionary stable. We show that in a two-stage Nash Demand Game such behavior survives. We also study the Ultimatum Game. Here evolutionary selection wipes out all tough behavior, as long as th...

  8. Decision Making in the Balloon Analogue Risk Task (BART): Anterior Cingulate Cortex Signals Loss-Aversion but not the Infrequency of Risky Choices

    Fukunaga, Rena; Brown, Joshua W.; Bogg, Tim

    2012-01-01

    The inferior frontal gyrus/anterior insula (IFG/AI) and anterior cingulate cortex (ACC) are key regions involved in risk appraisal during decision making, but accounts of how these regions contribute to decision-making under risk remain contested. To help clarify the roles of these and other related regions, we used a modified version of the Balloon Analogue Risk Task (Lejuez et al., 2002) to distinguish between decision-making and feedback-related processes when participants decided to pursue a gain as the probability of loss increased parametrically. Specifically, we set out to test whether ACC and IFG/AI regions correspond to loss-aversion at the time of decision making in a way that is not confounded with either reward-seeking or infrequency effects. When participants chose to discontinue inflating the balloon (win option), we observed greater ACC and mainly bilateral IFG/AI activity at the time of decision as the probability of explosion increased, consistent with increased loss-aversion but inconsistent with an infrequency effect. In contrast, we found robust vmPFC activity when participants chose to continue inflating the balloon (risky option), consistent with reward-seeking. However, in the cingulate and mainly bilateral IFG regions, BOLD activation decreased when participants chose to inflate the balloon as the probability of explosion increased, findings consistent with a reduced loss-aversion signal. Our results highlight the existence of distinct reward-seeking and loss-averse signals during decision-making, as well as the importance of distinguishing decision and feedback signals. PMID:22707378

  9. Decision making in the Balloon Analogue Risk Task (BART): anterior cingulate cortex signals loss aversion but not the infrequency of risky choices.

    Fukunaga, Rena; Brown, Joshua W; Bogg, Tim

    2012-09-01

    The inferior frontal gyrus/anterior insula (IFG/AI) and anterior cingulate cortex (ACC) are key regions involved in risk appraisal during decision making, but accounts of how these regions contribute to decision making under risk remain contested. To help clarify the roles of these and other related regions, we used a modified version of the Balloon Analogue Risk Task (Lejuez et al., Journal of Experimental Psychology: Applied, 8, 75-84, 2002) to distinguish between decision-making and feedback-related processes when participants decided to pursue a gain as the probability of loss increased parametrically. Specifically, we set out to test whether the ACC and IFG/AI regions correspond to loss aversion at the time of decision making in a way that is not confounded with either reward-seeking or infrequency effects. When participants chose to discontinue inflating the balloon (win option), we observed greater ACC and mainly bilateral IFG/AI activity at the time of decision as the probability of explosion increased, consistent with increased loss aversion but inconsistent with an infrequency effect. In contrast, we found robust vmPFC activity when participants chose to continue inflating the balloon (risky option), consistent with reward seeking. However, in the cingulate and in mainly bilateral IFG regions, blood-oxygenation-level-dependent activation decreased when participants chose to inflate the balloon as the probability of explosion increased, findings that are consistent with a reduced loss aversion signal. Our results highlight the existence of distinct reward-seeking and loss-averse signals during decision making, as well as the importance of distinguishing between decision and feedback signals.

  10. Helping consumers make more healthful food choices: consumer views on modifying food labels and providing point-of-purchase nutrition information at quick-service restaurants.

    Lando, Amy M; Labiner-Wolfe, Judith

    2007-01-01

    To understand consumer (1) interest in nutrition information on food labels and quick-service restaurant menu boards and (2) reactions to modifying this information to help highlight calories and more healthful choices. Eight consumer focus groups, using a guide and stimuli. Focus group discussions in 4 US cities. A total of 68 consumers, with 7 to 10 per focus group. Authors prepared detailed summaries of discussions based on observation. Video recordings and transcripts were used to cross-check summaries. Data were systematically reviewed, synthesized, and analyzed. Consumer views on alternative presentations of nutrition information on packaged food items and quick-service restaurant menu boards. Participants (1) were interested in having nutrition information available, but would not use it at every eating occasion; (2) thought that food products typically consumed at 1 eating occasion should be labeled as a single serving; and (3) indicated that an icon on labels and menu boards that signaled more healthful options could be helpful. Findings provide a basis for the development of more systematic studies to better understand whether alternative presentations of nutrition information would help consumers.

  11. Application of multi-criteria decision-making model for choice of the optimal solution for meeting heat demand in the centralized supply system in Belgrade

    Grujić, Miodrag; Ivezić, Dejan; Živković, Marija

    2014-01-01

    The expected growth of living standard, number of inhabitants and development of technology, industry and agriculture will cause a significant increase of energy consumption in cities. Three scenarios of energy sector development until 2030 and corresponding energy consumption for the city of Belgrade are analyzed in this paper. These scenarios consider different level of economic development, investments in energy sector, substitution of fossil fuels, introduction of renewable energy sources and implementation of energy efficiency measures. The proposed model for selection of optimal district heating system compares different options for fulfilling expected new heat demand through eight criteria for each scenario. Proposed options are combination of different energy sources and technologies for their use. The criteria weights are set according to Serbian economy and energy position. The criteria include financial aspects, environmental impact and availability of energy. Multi-criteria method ELECTRE (ELimination Et Choix Traduisant la REalite) is used as a tool for obtaining the optimal option. It is concluded that combination of CHP (combined heat and power) plant and centralized use of geothermal energy is optimal choice in the optimistic scenario. In the pessimistic and business as usual scenario the optimal option is combination of new gas boilers and centralized use of geothermal energy. - Highlights: • Three scenarios for meeting new heat demand are developed and assessed. • Constructing CHP (combined heat and power) is desirable in case of significant electricity price growth. • In all scenarios the chosen option includes using geothermal energy for heating

  12. Making sense of policy choices: understanding the roles of value predispositions, mass media, and cognitive processing in public attitudes toward nanotechnology

    Ho, Shirley S.; Scheufele, Dietram A.; Corley, Elizabeth A.

    2010-10-01

    Using a nationally representative telephone survey of 1,015 adults in the United States, this study examines how value predispositions, communication variables, and perceptions of risks and benefits are associated with public support for federal funding of nanotechnology. Our findings show that highly religious individuals were less supportive of funding of nanotech than less religious individuals, whereas individuals who held a high deference for scientific authority were more supportive of funding of the emerging technology than those low in deference. Mass media use and elaborative processing of scientific news were positively associated with public support for funding, whereas factual scientific knowledge had no significant association with policy choices. The findings suggest that thinking about and reflecting upon scientific news promote better understanding of the scientific world and may provide a more sophisticated cognitive structure for the public to form opinions about nanotech than factual scientific knowledge. Finally, heuristic cues including trust in scientists and perceived risks and benefits of nanotech were found to be associated with public support for nanotech funding. We conclude with policy implications that will be useful for policymakers and science communication practitioners.

  13. Making sense of policy choices: understanding the roles of value predispositions, mass media, and cognitive processing in public attitudes toward nanotechnology

    Ho, Shirley S.; Scheufele, Dietram A.; Corley, Elizabeth A.

    2010-01-01

    Using a nationally representative telephone survey of 1,015 adults in the United States, this study examines how value predispositions, communication variables, and perceptions of risks and benefits are associated with public support for federal funding of nanotechnology. Our findings show that highly religious individuals were less supportive of funding of nanotech than less religious individuals, whereas individuals who held a high deference for scientific authority were more supportive of funding of the emerging technology than those low in deference. Mass media use and elaborative processing of scientific news were positively associated with public support for funding, whereas factual scientific knowledge had no significant association with policy choices. The findings suggest that thinking about and reflecting upon scientific news promote better understanding of the scientific world and may provide a more sophisticated cognitive structure for the public to form opinions about nanotech than factual scientific knowledge. Finally, heuristic cues including trust in scientists and perceived risks and benefits of nanotech were found to be associated with public support for nanotech funding. We conclude with policy implications that will be useful for policymakers and science communication practitioners.

  14. Validity of fracture toughness determined with small bend specimens

    Wallin, K.; Rintamaa, R.; Valo, M.

    1994-02-01

    This report considers the validity of fracture toughness estimates obtained with small bend specimens in relation to fracture toughness estimates obtained with large specimens. The study is based upon the analysis and comparison of actual test results. The results prove the validity of the fracture toughness determined based upon small bend specimens, especially when the results are only used to determine the fracture toughness transition temperature T o . In this case the possible error is typically less than 5 deg C and at most 10 deg C. It can be concluded that small bend specimens are very suitable for the estimation of fracture toughness in the case of brittle fracture, provided the results are corrected for statistical size effects. (orig.). (20 refs., 17 figs.)

  15. The fracture toughness of Type 316 steel and weld metal

    Picker, C.

    This paper describes the results of fracture toughness tests on Type 316 steel and Manual Metal Arc (MMA) weld metal over a range of temperatures from 20 deg. C to 550 deg. C, and includes the effects on toughness of specimen size, post weld heat treatment and thermal ageing. The conclusions reached are that Type 316 steel possesses a superior toughness to the weld metal in the as-welded or stress relieved conditions but the toughness of the steel is degraded to a level similar to that of the weld metal following thermal ageing at temperatures over 600 deg. C. Relatively short term thermal ageing in the temperature range 370 deg. C to 450 deg. C does not appear to affect the toughness of either Type 316 steel or weld metal. (author)

  16. Evaluation of fracture toughness of ductile cast iron for casks

    Hide, Koh-ichiro; Arai, Taku; Takaku, Hiroshi; Shimazaki, Katsunori; Kusanagi, Hideo

    1988-01-01

    We studied the fracture toughness and tensile properties of ductile cast iron for casks, and tried to introduce a fatigue crack into partial cask model. Main results were shown as follows. (1) Fracture toughness were in the upper shelf area above -25deg C, and were in the transition area at -40 and -70deg C. (2) Increasing the value of K I , the fracture toughness decreased. (3) Increasing the specimen thickness, fracture toughness decreased. (4) Fracture toughness of an artificial flaw (ρ=0.1 mm) was the same as that of a fatigue crack at -40deg C. (5) Tensil properties were inferior at -196 and about 400deg C because of low temperature brittleness and blue brittleness. (6) Tensile properties in the middle of cask wall were inferior. (7) It seems to be possible to introduce a fatigue crack into a full size cask. (author)

  17. Fracture toughness measurements with subsize disk compact specimens

    Alexander, D.J.

    1994-01-01

    Special fixtures and test methods have been developed for testing small disk compact specimens (1.25 mm diam by 4.6 mm thick). Specimens of European type 316L austenitic stainless steel were irradiated to damage levels of about 3 dpa at nominal irradiation temperatures of either 90 or 250 C and tested over a temperature range from 20 to 250 C. Results show that irradiation to this dose level at these temperatures reduces the fracture toughness but the toughness remains quite high. The toughness decreases as the test temperature increases. Irradiation at 250 C is more damaging than at 90 C, causing larger decreases in the fracture toughness. The testing shows that it is possible to generate useful fracture toughness data with a small disk compact specimens

  18. Fracture toughness of irradiated and recovered vessel steels

    Perosanz, F.; Lapena, J.

    1998-01-01

    This paper presents the fracture toughness measurements carried out on three vessel steels in an irradiated condition and after a post-irradiation recovery treatment. A statistical approach and the fracture parameters corresponding to two theoretical models of the fracture tests are used for evaluating toughness. Test results show that the neutron fluence gradually transforms the fracture behaviour of the vessel steels from ductile to brittle and seriously reduces their fracture toughness. The effectiveness of the recovery treatment, as evaluated from the toughness measurements, is confirmed, although the efficiency is not the same for the steels and depends on the evaluation parameter except in the case of almost complete recovery. The recovery effect increases with the received neutron fluence if the toughness values after treatment are compared with those in the irradiated condition rather than those in the as received condition. (orig.)

  19. Toughness degradation evaluation of low alloyed steels by electrical resistivity

    Nahm, S H; Yu, K M; Kim, S C [Korea Research Inst. of Standards and Science, Taejon (Korea, Republic of); Kim, A [Department of Mechanical Engineering, Kongju Univ., Kongju, Chungnam (Korea, Republic of)

    1997-09-01

    Remaining life of turbine rotors with a crack can be assessed by the fracture toughness on the aged rotors at service temperature. DC potential drop measurement system was constructed in order to evaluate material toughness nondestructively. Test material was 1Cr-1Mo-0.25V steel used widely for turbine rotor material. Seven kinds of specimen with different degradation levels were prepared according to isothermal aging heat treatment at 630 deg. C. Electrical resistivity of test material was measured at room temperature. It was observed that material toughness and electrical resistivity decreased with the increase of degradation. The relationship between fracture toughness and electrical resistivity was investigated. Fracture toughness of a test material may be determined nondestructively by electrical resistivity. (author). 13 refs, 7 figs.

  20. Fracture toughness testing of pipeline girth welds

    Shen, G.; Gianetto, J.A.; Bouchard, R.; Bowker, J.T.; Tyson, W.R.

    2005-06-01

    This paper reviewed the fracture toughness test standards for pipeline girth welds outlined in CSA Z662-03, Annex K as well as the referenced testing standards BS 7448 and ASTM Standard E 1290. The requirements outlined in API 1104, appendix A were also reviewed given its application throughout the world. Crack tip opening displacement (CTOD) tests were conducted on a manual shielded-metal-arc weld (SMAW) that was prepared in a high strength X80 pipeline steel. Another girth weld test consisted of a mechanized gas metal arc weld (GMAW), but only the results for the SMAW were presented in this paper. Two tensile specimens were machined parallel to the pipe axis from the base metal of the X80 pipe used in preparing the pipeline girth welds. The tensile specimens from the pipe base metal and weld metal were tested at 20 degrees C. The yield strength at the CTOD test temperature was estimated by using the yield strength-temperature relationship given in BS 7448. The experimental results obtained by applying the two testing standards were compared. The intent was to identify the differences between these two standards and their influence on test results. The authors discussed critical issues for the fracture toughness tests, such as weld position and notch orientation, circumferential sampling location, residual stress and its modification, crack length measurement and the equations used to evaluate CTOD. The variation of strength and toughness with clock position around the circumference of the girth welds was also discussed. It was concluded that for a high-strength material, local compression may be needed to create a uniform fatigue crack front. For deep-cracked specimens, the maximum allowable difference of the measured fatigue crack length varies significantly between ASTM E 1290-02 and BS 7448 by a factor of about 1 to 3 for ASTM E 1290 and 3 to 15 for BS 7448. The CTOD calculated according to ASTM E 1290-02 and according to BS 7448 can also differ substantially

  1. Graphical user interface for TOUGH/TOUGH2 - development of database, pre-processor, and post-processor

    Sato, Tatsuya; Okabe, Takashi; Osato, Kazumi [Geothermal Energy Research and Development Co., Ltd., Tokyo (Japan)

    1995-03-01

    One of the advantages of the TOUGH/TOUGH2 (Pruess, 1987 and 1991) is the modeling using {open_quotes}free shape{close_quotes} polygonal blocks. However, the treatment of three-dimensional information, particularly for TOUGH/TOUGH2 is not easy because of the {open_quotes}free shape{close_quotes} polygonal blocks. Therefore, we have developed a database named {open_quotes}GEOBASE{close_quotes} and a pre/post-processor named {open_quotes}GEOGRAPH{close_quotes} for TOUGH/TOUGH2 on engineering work station (EWS). {open_quotes}GEOGRAPH{close_quotes} is based on the ORACLE{sup *1} relational database manager system to access data sets of surface exploration (geology, geophysics, geochemistry, etc.), drilling (well trajectory, geological column, logging, etc.), well testing (production test, injection test, interference test, tracer test, etc.) and production/injection history.{open_quotes}GEOGRAPH{close_quotes} consists of {open_quotes}Pre-processor{close_quotes} that can construct the three-dimensional free shape reservoir modeling by mouse operation on X-window and {open_quotes}Post-processor{close_quotes} that can display several kinds of two/three-dimensional maps and X-Y plots to compile data on {open_quotes}GEOBASE{close_quotes} and result of TOUGH/TOUGH2 calculation. This paper shows concept of the systems and examples of utilization.

  2. Fracture toughness for copper oxide superconductors

    Goretta, K.C.; Kullberg, M.L.

    1993-04-13

    An oxide-based strengthening and toughening agent, such as tetragonal ZrO[sub 2] particles, has been added to copper oxide superconductors, such as superconducting YBa[sub 2]Cu[sub 3]O[sub x] (123) to improve its fracture toughness (K[sub IC]). A sol-gel coating which is non-reactive with the superconductor, such as Y[sub 2]BaCuO[sub 5] (211) on the ZrO[sub 2] particles minimized the deleterious reactions between the superconductor and the toughening agent dispersed therethrough. Addition of 20 mole percent ZrO[sub 2] coated with 211 yielded a 123 composite with a K[sub IC] of 4.5 MPa(m)[sup 0.5].

  3. Fracture toughness for copper oxide superconductors

    Goretta, Kenneth C.; Kullberg, Marc L.

    1993-01-01

    An oxide-based strengthening and toughening agent, such as tetragonal Zro.sub.2 particles, has been added to copper oxide superconductors, such as superconducting YBa.sub.2 Cu.sub.3 O.sub.x (123) to improve its fracture toughness (K.sub.IC). A sol-gel coating which is non-reactive with the superconductor, such as Y.sub.2 BaCuO.sub.5 (211) on the ZrO.sub.2 particles minimized the deleterious reactions between the superconductor and the toughening agent dispersed therethrough. Addition of 20 mole percent ZrO.sub.2 coated with 211 yielded a 123 composite with a K.sub.IC of 4.5 MPa(m).sup.0.5.

  4. Decision making for destination therapy left ventricular assist devices: "there was no choice" versus "I thought about it an awful lot".

    McIlvennan, Colleen K; Allen, Larry A; Nowels, Carolyn; Brieke, Andreas; Cleveland, Joseph C; Matlock, Daniel D

    2014-05-01

    Destination therapy left ventricular assist devices (DT LVADs) are one of the most invasive medical interventions for end-stage illness. How patients decide whether or not to proceed with device implantation is unknown. We aimed to understand the decision-making processes of patients who either accept or decline DT LVADs. Between October 2012 and September 2013, we conducted semistructured, in-depth interviews to understand patients' decision-making experiences. Data were analyzed using a mixed inductive and deductive approach. Twenty-two eligible patients were interviewed, 15 with DT LVADs and 7 who declined. We found a strong dichotomy between decision processes with some patients (11 accepters) being automatic and others (3 accepters, 7 decliners) being reflective in their approach to decision making. The automatic group was characterized by a fear of dying and an over-riding desire to live as long as possible: "[LVAD] was the only option I had…that or push up daisies…so I automatically took this." By contrast, the reflective group went through a reasoned process of weighing risks, benefits, and burdens: "There are worse things than death." Irrespective of approach, most patients experienced the DT LVAD decision as a highly emotional process and many sought support from their families or spiritually. Some patients offered a DT LVAD face the decision by reflecting on a process and reasoning through risks and benefits. For others, the desire to live supersedes such reflective processing. Acknowledging this difference is important when considering how to support patients who are faced with this complex decision. © 2014 American Heart Association, Inc.

  5. The VMAT-2 inhibitor tetrabenazine affects effort-related decision making in a progressive ratio/chow feeding choice task: reversal with antidepressant drugs.

    Patrick A Randall

    Full Text Available Behavioral activation is a fundamental feature of motivation, and organisms frequently make effort-related decisions based upon evaluations of reinforcement value and response costs. Furthermore, people with major depression and other disorders often show anergia, psychomotor retardation, fatigue, and alterations in effort-related decision making. Tasks measuring effort-based decision making can be used as animal models of the motivational symptoms of depression, and the present studies characterized the effort-related effects of the vesicular monoamine transport (VMAT-2 inhibitor tetrabenazine. Tetrabenazine induces depressive symptoms in humans, and also preferentially depletes dopamine (DA. Rats were assessed using a concurrent progressive ratio (PROG/chow feeding task, in which they can either lever press on a PROG schedule for preferred high-carbohydrate food, or approach and consume a less-preferred lab chow that is freely available in the chamber. Previous work has shown that the DA antagonist haloperidol reduced PROG work output on this task, but did not reduce chow intake, effects that differed substantially from those of reinforcer devaluation or appetite suppressant drugs. The present work demonstrated that tetrabenazine produced an effort-related shift in responding on the PROG/chow procedure, reducing lever presses, highest ratio achieved and time spent responding, but not reducing chow intake. Similar effects were produced by administration of the subtype selective DA antagonists ecopipam (D1 and eticlopride (D2, but not by the cannabinoid CB1 receptor neutral antagonist and putative appetite suppressant AM 4413, which suppressed both lever pressing and chow intake. The adenosine A2A antagonist MSX-3, the antidepressant and catecholamine uptake inhibitor bupropion, and the MAO-B inhibitor deprenyl, all reversed the impairments induced by tetrabenazine. This work demonstrates the potential utility of the PROG/chow procedure as a

  6. The loss of activating transcription factor 4 (ATF4) reduces bone toughness and fracture toughness.

    Makowski, Alexander J; Uppuganti, Sasidhar; Wadeer, Sandra A; Whitehead, Jack M; Rowland, Barbara J; Granke, Mathilde; Mahadevan-Jansen, Anita; Yang, Xiangli; Nyman, Jeffry S

    2014-05-01

    Even though age-related changes to bone tissue affecting fracture risk are well characterized, only a few matrix-related factors have been identified as important to maintaining fracture resistance. As a gene critical to osteoblast differentiation, activating transcription factor 4 (ATF4) is possibly one of these important factors. To test the hypothesis that the loss of ATF4 affects the fracture resistance of bone beyond bone mass and structure, we harvested bones from Atf4+/+ and Atf4-/- littermates at 8 and 20 weeks of age (n≥9 per group) for bone assessment across several length scales. From whole bone mechanical tests in bending, femurs from Atf4-/- mice were found to be brittle with reduced toughness and fracture toughness compared to femurs from Atf4+/+ mice. However, there were no differences in material strength and in tissue hardness, as determined by nanoindentation, between the genotypes, irrespective of age. Tissue mineral density of the cortex at the point of loading as determined by micro-computed tomography was also not significantly different. However, by analyzing local composition by Raman Spectroscopy (RS), bone tissue of Atf4-/- mice was found to have higher mineral to collagen ratio compared to wild-type tissue, primarily at 20 weeks of age. From RS analysis of intact femurs at 2 orthogonal orientations relative to the polarization axis of the laser, we also found that the organizational-sensitive peak ratio, ν1Phosphate per Amide I, changed to a greater extent upon bone rotation for Atf4-deficient tissue, implying bone matrix organization may contribute to the brittleness phenotype. Target genes of ATF4 activity are not only important to osteoblast differentiation but also in maintaining bone toughness and fracture toughness. Published by Elsevier Inc.

  7. The Loss of Activating Transcription Factor 4 (ATF4) Reduces Bone Toughness and Fracture Toughness

    Makowski, Alexander J.; Uppuganti, Sasidhar; Waader, Sandra A.; Whitehead, Jack M.; Rowland, Barbara J.; Granke, Mathilde; Mahadevan-Jansen, Anita; Yang, Xiangli; Nyman, Jeffry S.

    2014-01-01

    Even though age-related changes to bone tissue affecting fracture risk are well characterized, only a few matrix-related factors have been identified as important to maintaining fracture resistance. As a gene critical to osteoblast differentiation, activating transcription factor 4 (ATF4) is possibly one of the seimportant factors. To test the hypothesis that the loss of ATF4 affects the fracture resistance of bone beyond bone mass and structure, we harvested bones from Atf4+/+ and Atf4−/− littermates at 8 and 20 weeks of age (n≥9 per group) for bone assessment across several length scales. From whole bone mechanical tests in bending, femurs from Atf4−/− mice were found to be brittle with reduced toughness and fracture toughness compared to femurs from Atf4+/+ mice. However, there were no differences in material strength and in tissue hardness, as determined by nanoindentation, between the genotypes, irrespective age. Tissue mineral density of the cortex at the point of loading as determined by micro-computed tomography was also not significantly different. However, by analyzing local composition by Raman Spectroscopy (RS), bone tissue of Atf4−/− mice was found to have higher mineral to collagen ratio compared to wild-type tissue, primarily at 20 weeks of age. From RS analysis of intact femurs at 2 orthogonal orientations relative to the polarization axis of the laser, we also found that the organizational-sensitive peak ratio, ν1 Phosphate per Amide I, changed to a greater extent upon bone rotation for Atf4-deficient tissue, implying bone matrix organization may contribute to the brittleness phenotype. Target genes of ATF4 activity are not only important to osteoblast differentiation but also maintaining bone toughness and fracture toughness. PMID:24509412

  8. The Evolution of Plate and Extruded Products with High Strength and Fracture Toughness

    Denzer, D. K.; Rioja, R. J.; Bray, G. H.; Venema, G. B.; Colvin, E. L.

    From the first use of 2017-T74 on the Junkers F13, improvements have been made to plate and extruded products for applications requiring the highest attainable strength and adequate fracture toughness. One such application is the upper wing of large aircraft. The progression of these product improvements achieved through the development of alloys that include 7075-(T6 & T76), 7150-(T6 & T77) and 7055-(T77 & T79) and most recently 7255-(T77 & T79) is reviewed. The most current advancements include aluminum-copper-lithium, alloy 2055 plate and extruded products that can attain strength equivalent to that of 7055-T77 with higher modulus, similar fracture toughness and improved fatigue, fatigue crack growth and corrosion performance. The achievement of these properties is explained in terms of the several alloy design principles. The highly desired and balanced characteristics make these products ideal for upper wing applications.

  9. Vincent's Choice

    Stolwijk, Chris

    2003-01-01

    Official publication to accompany the important exhibition Vincent's Choice, Van Gogh's 'musee imaginaire' at the Van Gogh Museum, Amsterdam marking the 150th anniversary of the artist's birth. The exhibition runs from 14th February to 15th June 2003.Thanks to van Gogh's correspondence, it has been

  10. Cued to Act on Impulse: More Impulsive Choice and Risky Decision Making by Women Susceptible to Overeating after Exposure to Food Stimuli.

    Martin R Yeomans

    Full Text Available There is increasing evidence that individual differences in tendency to overeat relate to impulsivity, possibly by increasing reactivity to food-related cues in the environment. This study tested whether acute exposure to food cues enhanced impulsive and risky responses in women classified on tendency to overeat, indexed by scores on the three factor eating questionnaire disinhibition (TFEQ-D, restraint (TFEQ-R and hunger scales. Ninety six healthy women completed two measures of impulsive responding (delayed discounting, DDT and a Go No-Go, GNG, task and a measure of risky decision making (the balloon analogue risk task, BART as well as questionnaire measures of impulsive behaviour either after looking at a series of pictures of food or visually matched controls. Impulsivity (DDT and risk-taking (BART were both positively associated with TFEQ-D scores, but in both cases this effect was exacerbated by prior exposure to food cues. No effects of restraint were found. TFEQ-D scores were also related to more commission errors on the GNG, while restrained women were slower on the GNG, but neither effect was modified by cue exposure. Overall these data suggest that exposure to food cues act to enhance general impulsive responding in women at risk of overeating and tentatively suggest an important interaction between tendency for impulsive decision making and food cues that may help explain a key underlying risk factor for overeating.

  11. Cued to Act on Impulse: More Impulsive Choice and Risky Decision Making by Women Susceptible to Overeating after Exposure to Food Stimuli.

    Yeomans, Martin R; Brace, Aaron

    2015-01-01

    There is increasing evidence that individual differences in tendency to overeat relate to impulsivity, possibly by increasing reactivity to food-related cues in the environment. This study tested whether acute exposure to food cues enhanced impulsive and risky responses in women classified on tendency to overeat, indexed by scores on the three factor eating questionnaire disinhibition (TFEQ-D), restraint (TFEQ-R) and hunger scales. Ninety six healthy women completed two measures of impulsive responding (delayed discounting, DDT and a Go No-Go, GNG, task) and a measure of risky decision making (the balloon analogue risk task, BART) as well as questionnaire measures of impulsive behaviour either after looking at a series of pictures of food or visually matched controls. Impulsivity (DDT) and risk-taking (BART) were both positively associated with TFEQ-D scores, but in both cases this effect was exacerbated by prior exposure to food cues. No effects of restraint were found. TFEQ-D scores were also related to more commission errors on the GNG, while restrained women were slower on the GNG, but neither effect was modified by cue exposure. Overall these data suggest that exposure to food cues act to enhance general impulsive responding in women at risk of overeating and tentatively suggest an important interaction between tendency for impulsive decision making and food cues that may help explain a key underlying risk factor for overeating.

  12. The emerging role of histology in the choice of first-line treatment of advanced non-small cell lung cancer: implication in the clinical decision-making.

    Rossi, Antonio; Maione, Paolo; Bareschino, Maria Anna; Schettino, Clorinda; Sacco, Paola Claudia; Ferrara, Marianna Luciana; Castaldo, Vincenzo; Gridelli, Cesare

    2010-01-01

    Lung cancer is the leading cause of cancer mortality worldwide. Non-small cell lung cancer (NSCLC), accounting for about 85% of all lung cancers, includes squamous carcinoma, adenocarcinoma and undifferentiated large cell carcinoma. The majority of patients have advanced disease at diagnosis, and medical treatment is the cornerstone of management. Several randomized trials comparing third-generation platinum-based doublets concluded that all such combinations are comparable in their clinical efficacy, failing to document a difference based on histology. However, recent evidences, arising from the availability of pemetrexed, have shown that histology represents an important variable in the decision making. The major progresses in the understanding cancer biology and mechanism of oncogenesis have allowed the development of several potential molecular targets for cancer treatment such as vascular growth factor and its receptors and epidermal growth factor receptor. Targeted drugs seem to be safer or more effective in a specific histology subtype. All of these data have led to choose the optimal first-line treatment of advanced NSCLC based on histologic diagnosis. However, this scenario raises a diagnostic issue: a specific diagnosis of NSCLC histologic subtype is mandatory. This review will discuss these new evidences in the first-line treatment of advanced NSCLC and their implication in the current clinical decision-making.

  13. A Qualitative Analysis of Patients' Perceptions of Shared Decision Making in the Emergency Department: "Let Me Know I Have a Choice".

    Schoenfeld, Elizabeth M; Goff, Sarah L; Downs, Gwendolyn; Wenger, Robert J; Lindenauer, Peter K; Mazor, Kathleen M

    2018-03-25

    Despite increasing attention to the use of shared decision making (SDM) in the emergency department (ED), little is known about ED patients' perspectives regarding this practice. We sought to explore the use of SDM from the perspectives of ED patients, focusing on what affects patients' desired level of involvement and what barriers and facilitators patients find most relevant to their experience. We conducted semistructured interviews with a purposive sample of ED patients or their proxies at two sites. An interview guide was developed from existing literature and expert consensus and based on a framework underscoring the importance of both knowledge and power. Interviews were recorded, transcribed, and analyzed in an iterative process by a three-person coding team. Emergent themes were identified, discussed, and organized. Twenty-nine patients and proxies participated. The mean age of participants was 56 years (range, 20 to 89 years), and 13 were female. Participants were diverse in regard to race/ethnicity, education, number of previous ED visits, and presence of chronic conditions. All participants wanted some degree of involvement in decision making. Participants who made statements suggesting high self-efficacy and those who expressed mistrust of the health care system or previous negative experiences wanted a greater degree of involvement. Facilitators to involvement included familiarity with the decision at hand, physicians' good communication skills, and clearly delineated options. Some participants felt that their own relative lack of knowledge, compared to that of the physicians, made their involvement inappropriate or unwanted. Many participants had no expectation for SDM and although they did want involvement when asked explicitly, they were otherwise likely to defer to physicians without discussion. Many did not recognize opportunities for SDM in their clinical care. This exploration of ED patients' perceptions of SDM suggests that most patients want

  14. Fracture toughness of mountain gorilla (Gorilla gorilla beringei) food plants.

    Elgart-Berry, Alison

    2004-04-01

    Mountain gorillas, the largest extant primates, subsist almost entirely on plant matter. Moreover, their diet includes a substantial amount of structural material, such as bark and stems, which other primates tend to avoid. Accordingly, the robust masticatory apparatus of gorillas may be adaptive to this presumably tough diet; however, quantitative information on this subject is lacking. In this study the fracture toughness of mountain gorilla foods was examined for the first time. Samples of 44 food plants from Bwindi-Impenetrable National Park (BINP) and Mgahinga Gorilla National Park (MGNP) were tested. These parks are inhabited by two gorilla populations that regarded by some as being distinct at the subspecific taxonomic level. Although food toughness did not differ between the two populations, both diets contained tough items. Tree barks were the toughest food items (varying from 0.23 to 8.2 kJ/m2), followed by shrub barks, pith, and stems. The toughness of leaves and fruit was negligible compared to that of bark. The toughness of bamboo was low in comparison to the toughest food items. Accordingly, the prominent toughness of bark, pith, and stems may be key factors in the evolution of orofacial robusticity in mountain gorillas. Copyright 2004 Wiley-Liss, Inc.

  15. [GRADE Evidence to Decision (EtD) frameworks: a systematic and transparent approach to making well informed healthcare choices. 1: Introduction].

    Alonso-Coello, Pablo; Schünemann, Holger J; Moberg, Jenny; Brignardello-Petersen, Romina; Akl, Elie A; Davoli, Marina; Treweek, Shaun; Mustafa, Reem A; Rada, Gabriel; Rosenbaum, Sarah; Morelli, Angela; Guyatt, Gordon H; Oxman, Andrew D

    Clinicians, guideline developers, and policymakers sometimes neglect important criteria, give undue weight to criteria, and do not use the best available evidence to inform their judgments. Explicit and transparent systems for decision making can help to ensure that all important criteria are considered and that decisions are informed by the best available research evidence. The GRADE Working Group has developed Evidence to Decision (EtD) frameworks for the different type of recommendations or decisions. The purpose of EtD frameworks is to help people use evidence in a structured and transparent way to inform decisions in the context of clinical recommendations, coverage decisions, and health system or public health recommendations and decisions. EtD frameworks have a common structure that includes formulation of the question, an assessment of the evidence, and drawing conclusions, though there are some differences between frameworks for each type of decision. EtD frameworks inform users about the judgments that were made and the evidence supporting those judgments by making the basis for decisions transparent to target audiences. EtD frameworks also facilitate dissemination of recommendations and enable decision makers in other jurisdictions to adopt recommendations or decisions, or adapt them to their context. This article is a translation of the original article published in British Medical Journal. The EtD frameworks are currently used in the Clinical Practice Guideline Programme of the Spanish National Health System, co-ordinated by GuíaSalud. Copyright © 2017 SESPAS. Publicado por Elsevier España, S.L.U. All rights reserved.

  16. Choosing health, constrained choices.

    Chee Khoon Chan

    2009-12-01

    In parallel with the neo-liberal retrenchment of the welfarist state, an increasing emphasis on the responsibility of individuals in managing their own affairs and their well-being has been evident. In the health arena for instance, this was a major theme permeating the UK government's White Paper Choosing Health: Making Healthy Choices Easier (2004), which appealed to an ethos of autonomy and self-actualization through activity and consumption which merited esteem. As a counterpoint to this growing trend of informed responsibilization, constrained choices (constrained agency) provides a useful framework for a judicious balance and sense of proportion between an individual behavioural focus and a focus on societal, systemic, and structural determinants of health and well-being. Constrained choices is also a conceptual bridge between responsibilization and population health which could be further developed within an integrative biosocial perspective one might refer to as the social ecology of health and disease.

  17. Neural Activity Reveals Preferences Without Choices

    Smith, Alec; Bernheim, B. Douglas; Camerer, Colin

    2014-01-01

    We investigate the feasibility of inferring the choices people would make (if given the opportunity) based on their neural responses to the pertinent prospects when they are not engaged in actual decision making. The ability to make such inferences is of potential value when choice data are unavailable, or limited in ways that render standard methods of estimating choice mappings problematic. We formulate prediction models relating choices to “non-choice” neural responses and use them to predict out-of-sample choices for new items and for new groups of individuals. The predictions are sufficiently accurate to establish the feasibility of our approach. PMID:25729468

  18. The effect of specimen and flaw dimensions on fracture toughness

    Nevalainen, M.J.

    1997-06-01

    The effect of the specimen size and geometry on fracture toughness has been investigated both by experimental tests and computational analyses. The methods for constraint description, namely T-stress, Q-parameter and Small-Scale Yielding Correction (SSYC) have been compared and applied for various geometries. A statistical treatment for the specimen thickness effect on cleavage fracture toughness has been investigated. Elliptical surface cracks were compared with straight-thickness cracks and a method for crack shape correction was presented. Based on the results, the differences in apparent fracture toughness values obtained from various specimen configurations can be better understood and taken into account

  19. Fracture toughness of ferritic alloys irradiated at FFTF

    Huang, F.H.

    1986-05-01

    Ferritic compact tension specimens loaded in the Material Open Test Assembly (MOTA) for irradiation during FFTF Cycle 4 were tested at temperatures ranging from room temperature to 428/degree/C. The electrical potential single specimen method was used to measure the fracture toughness of the specimens. Results showed that the fracture toughness of both HT-9 and 9Cr-1Mo decreases with increasing test temperature and that the toughness of HT-9 was about 30% higher than that of 9Cr-1Mo. In addition, increasing irradiation temperature resulted in an increase in tearing modulus for both alloys. 4 refs., 5 figs., 1 tab

  20. Fracture toughness of oxide-dispersion strengthened copper

    Alexander, D.J. [Oak Ridge National Lab., TN (United States)

    1996-10-01

    The fracture toughness of an oxide-dispersion strengthened copper alloy AL-15 has been examined at room temperature and 250{degrees}C, in air and in vacuum (< 10{sup {minus}6} torr). Increasing test temperature causes a significant decrease in the fracture toughness of this material, in either air or vacuum environments. In addition, specimens oriented in the T-L orientation (crack growth parallel to the extrusion direction) show significantly lower toughness than those in the L-T orientation (crack growth perpendicular to the extrusion direction).

  1. Pie technique of LWR fuel cladding fracture toughness test

    Endo, Shinya; Usami, Koji; Nakata, Masahito; Fukuda, Takuji; Numata, Masami; Kizaki, Minoru; Nishino, Yasuharu

    2006-01-01

    Remote-handling techniques were developed by cooperative research between the Department of Hot Laboratories in the Japan Atomic Energy Research Institute (JAERI) and the Nuclear Fuel Industries Ltd. (NFI) for evaluating the fracture toughness on irradiated LWR fuel cladding. The developed techniques, sample machining by using the electrical discharge machine (EDM), pre-cracking by fatigue tester, sample assembling to the compact tension (CT) shaped test fixture gave a satisfied result for a fracture toughness test developed by NFL. And post-irradiation examination (PIE) using the remote-handling techniques were carried out to evaluate the fracture toughness on BWR spent fuel cladding in the Waste Safety Testing Facility (WASTEF). (author)

  2. ADM guidance-Ceramics: Fracture toughness testing and method selection.

    Cesar, Paulo Francisco; Della Bona, Alvaro; Scherrer, Susanne S; Tholey, Michael; van Noort, Richard; Vichi, Alessandro; Kelly, Robert; Lohbauer, Ulrich

    2017-06-01

    The objective is within the scope of the Academy of Dental Materials Guidance Project, which is to provide dental materials researchers with a critical analysis of fracture toughness (FT) tests such that the assessment of the FT of dental ceramics is conducted in a reliable, repeatable and reproducible way. Fracture mechanics theory and FT methodologies were critically reviewed to introduce basic fracture principles and determine the main advantages and disadvantages of existing FT methods from the standpoint of the dental researcher. The recommended methods for FT determination of dental ceramics were the Single Edge "V" Notch Beam (SEVNB), Single Edge Precracked Beam (SEPB), Chevron Notch Beam (CNB), and Surface Crack in Flexure (SCF). SEVNB's main advantage is the ease of producing the notch via a cutting disk, SEPB allows for production of an atomically sharp crack generated by a specific precracking device, CNB is technically difficult, but based on solid fracture mechanics solutions, and SCF involves fracture from a clinically sized precrack. The IF test should be avoided due to heavy criticism that has arisen in the engineering field regarding the empirical nature of the calculations used for FT determination. Dental researchers interested in FT measurement of dental ceramics should start with a broad review of fracture mechanics theory to understand the underlying principles involved in fast fracture of ceramics. The choice of FT methodology should be based on the pros and cons of each test, as described in this literature review. Copyright © 2017 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  3. [GRADE Evidence to Decision (EtD) frameworks: a systematic and transparent approach to making well informed healthcare choices. 2: Clinical practice guidelines].

    Alonso-Coello, Pablo; Oxman, Andrew D; Moberg, Jenny; Brignardello-Petersen, Romina; Akl, Elie A; Davoli, Marina; Treweek, Shaun; Mustafa, Reem A; Vandvik, Per O; Meerpohl, Joerg; Guyatt, Gordon H; Schünemann, Holger J

    Clinicians do not have the time or resources to consider the underlying evidence for the myriad decisions they must make each day and, as a consequence, rely on recommendations from clinical practice guidelines. Guideline panels should consider all the relevant factors (criteria) that influence a decision or recommendation in a structured, explicit, and transparent way and provide clinicians with clear and actionable recommendations. In this article, we will describe the Evidence to Decision (EtD) frameworks for clinical practice recommendations. The general structure of the EtD framework for clinical recommendations is similar to EtD frameworks for other types of recommendations and decisions, and includes formulation of the question, an assessment of the different criteria, and conclusions. Clinical recommendations require considering criteria differently, depending on whether an individual patient or a population perspective is taken. For example, from an individual patient's perspective, out-of-pocket costs are an important consideration, whereas, from a population perspective, resource use (not only out-of-pocket costs) and cost effectiveness are important. From a population perspective, equity, acceptability, and feasibility are also important considerations, whereas the importance of these criteria is often limited from an individual patient perspective. Specific subgroups for which different recommendations may be required should be clearly identified and considered in relation to each criterion because judgments might vary across subgroups. This article is a translation of the original article published in the British Medical Journal. The EtD frameworks are currently used in the Clinical Practice Guideline Programme of the Spanish National Health System, co-ordinated by GuíaSalud. Copyright © 2017 SESPAS. Publicado por Elsevier España, S.L.U. All rights reserved.

  4. “We make choices we think are going to save us”: Debate and stance identification for online breast cancer CAM discussions

    Zhang, Shaodian; Qiu, Lin; Chen, Frank; Zhang, Weinan; Yu, Yong; Elhadad, Noémie

    2017-01-01

    Patients discuss complementary and alternative medicine (CAM) in online health communities. Sometimes, patients’ conflicting opinions toward CAM-related issues trigger debates in the community. The objectives of this paper are to identify such debates, identify controversial CAM therapies in a popular online breast cancer community, as well as patients’ stances towards them. To scale our analysis, we trained a set of classifiers. We first constructed a supervised classifier based on a long short-term memory neural network (LSTM) stacked over a convolutional neural network (CNN) to detect automatically CAM-related debates from a popular breast cancer forum. Members’ stances in these debates were also identified by a CNN-based classifier. Finally, posts automatically flagged as debates by the classifier were analyzed to explore which specific CAM therapies trigger debates more often than others. Our methods are able to detect CAM debates with F score of 77%, and identify stances with F score of 70%. The debate classifier identified about 1/6 of all CAM-related posts as debate. About 60% of CAM-related debate posts represent the supportive stance toward CAM usage. Qualitative analysis shows that some specific therapies, such as Gerson therapy and usage of laetrile, trigger debates frequently among members of the breast cancer community. This study demonstrates that neural networks can effectively locate debates on usage and effectiveness of controversial CAM therapies, and can help make sense of patients’ opinions on such issues under dispute. As to CAM for breast cancer, perceptions of their effectiveness vary among patients. Many of the specific therapies trigger debates frequently and are worth more exploration in future work. PMID:28967000

  5. Fracture Toughness Round Robin Test International in pressure tube materials

    Villagarcia, M.P.; Liendo, M.F.

    1993-01-01

    Part of the pressure tubes surveillance program of CANDU type reactors is to determine the fracture toughness using a special fracture specimen and test procedure. Atomic Energy of Canada Limited decided to hold a Round Robin Test International and 9 laboratories participated worldwide in which several pressure tube materials were selected: Zircaloy-2, Zr-2.5%Nb cold worked and Zr-2.5%Nb heat treated. The small specimens used held back the thickness and curvature of the tube. J-R curves at room temperature were obtained and the crack extension values were determined by electrical potential drop techniques. These values were compared with results generated from other laboratories and a bid scatter was founded. It could be due to slight variations in the test method or inhomogeneity of the materials and a statistical study must be done to see if there is any pattern. The next step for the Round Robin Test would be to make some modifications in the test method in order to reduce the scatter. (Author)

  6. Standard test method for plane-strain (Chevron-Notch) fracture toughness of metallic materials

    American Society for Testing and Materials. Philadelphia

    1997-01-01

    1.1 This test method covers the determination of plane-strain (chevron-notch) fracture toughnesses, KIv or KIvM, of metallic materials. Fracture toughness by this method is relative to a slowly advancing steady state crack initiated at a chevron-shaped notch, and propagating in a chevron-shaped ligament (Fig. 1). Some metallic materials, when tested by this method, exhibit a sporadic crack growth in which the crack front remains nearly stationary until a critical load is reached. The crack then becomes unstable and suddenly advances at high speed to the next arrest point. For these materials, this test method covers the determination of the plane-strain fracture toughness, KIvj or KIvM, relative to the crack at the points of instability. Note 1—One difference between this test method and Test Method E 399 (which measures KIc) is that Test Method E 399 centers attention on the start of crack extension from a fatigue precrack. This test method makes use of either a steady state slowly propagating crack, or a...

  7. Effect of copper precipitates on the toughness of low alloy steels for pressure boundary components

    Foehl, J.; Willer, D.; Katerbau, K.H.

    2004-01-01

    The ferritic bainitic steel 15NiCuMoNb5 (WB 36)is widely used for pressure boundary components. Due to the high copper content which leads to precipitation hardening high strength and toughness are characteristic for this type of steel. However, in the initial state, there is still a high amount of dissolved copper in an oversaturated state which makes the steel susceptible to thermal ageing. Ageing and annealing experiments were performed, and the change in microstructure was investigated by small angle neutron scattering (SANS), measurements of the residual electric resistance and hardness measurements. A correlation between micro structural changes and changes in mechanical properties could be established. It could clearly be shown that significant effects on strength and toughness have to be considered when the size of the copper rich precipitates vary in the range from 1.2 to 2.2 nm in radius. The changes in microstructure affect both, the Carpy impact transition temperature and the fracture toughness qualitatively and quantitatively in a similar way. The investigations have contributed to a better understanding of precipitation hardening by copper not only for this type of steel but also for copper containing steels and weld subjected to neutron irradiation. (orig.)

  8. Fracture toughness measurements of WC-based hard metals

    Prakash, L.; Albert, B.

    1983-01-01

    The fracture toughness of WC-based cemented carbides was determined by different methods. The values obtained are dependent on the procedure of measurement. Each method thoughness of hard metals mutually. (orig.) [de

  9. The nature of mental toughness in sport | Fourie | South African ...

    South African Journal for Research in Sport, Physical Education and Recreation ... mental requirements, team unity, preparation skills, psychological hardiness, ... sport psychologists in strengthening the characteristics of mental toughness ...

  10. Strong, tough and stiff bioinspired ceramics from brittle constituents

    Bouville, Florian; Maire, Eric; Meille, Sylvain; van de Moortèle, Bertrand; Stevenson, Adam J.; Deville, Sylvain

    2014-05-01

    High strength and high toughness are usually mutually exclusive in engineering materials. In ceramics, improving toughness usually relies on the introduction of a metallic or polymeric ductile phase, but this decreases the material’s strength and stiffness as well as its high-temperature stability. Although natural materials that are both strong and tough rely on a combination of mechanisms operating at different length scales, the relevant structures have been extremely difficult to replicate. Here, we report a bioinspired approach based on widespread ceramic processing techniques for the fabrication of bulk ceramics without a ductile phase and with a unique combination of high strength (470 MPa), high toughness (22 MPa m1/2), and high stiffness (290 GPa). Because only mineral constituents are needed, these ceramics retain their mechanical properties at high temperatures (600 °C). Our bioinspired, material-independent approach should find uses in the design and processing of materials for structural, transportation and energy-related applications.

  11. Fracture toughness of Dy123 low porosity bulks at liquid nitrogen temperature

    Murakami, A.; Otaka, K.; Miura, T.; Iwamoto, A.

    2011-01-01

    Fracture toughness values were measured for Dy123 bulks. Fracture toughness was improved by reducing porosity. Fracture toughness values at 77 K were higher than those at room temperature. Fracture toughness was also improved by Ag addition. In order to evaluate the fracture toughness of DyBa 2 Cu 3 O x (Dy123) low porosity bulks, bending tests of V-notched specimens cut from the bulks were carried out. Fracture toughness evaluations of a conventional Dy123 bulk which had pores were also carried out and effects of elimination of pores on the fracture toughness were investigated. Fracture toughness values at 77 K of the low porosity bulks were higher than those of the porous bulk. These fracture toughness values at 77 K were higher than the values at room temperature. Fracture toughness of the low porosity bulk was improved by Ag addition.

  12. A Comparative Study on Emotional Intelligence and Mental Toughness for Visually Impaired Male and Female Athletes

    Robabeh Rostami

    2015-10-01

    Full Text Available Background: Nowadays researches find that athlete’s performance is affected not only by physical fitness, technical and tactical factors, but also mental and emotional features can affect sport performance. Objective: Hence, the aim of this study is examined the dimensions of emotional intelligence and mental toughness visually impaired male and female athletes. Methodology: This was a causal-comparative study, where the statistical population included 300 visually impaired male and female athletes taking part in the First National Cultural- Sports Festival featuring goalball, tug-of-war, track and field, swimming, and powerlifting. Using a smaple of convenience, 70 participants completed the Sheard, Golby, and van Wersch-questionnaire on mental toughness in three dimensions of  “confidence” “ control” and “constancy”, and the Petrides and Furnham’s questionnaire in four dimensions of “ understanding emotions”, “ social skills” “ controlling emotions” and “ optimism”. Results: Analysis of variables using an independent t-test showed significant differences in the dimensions of controlling emotions, understanding emotions, and social skills in favor of visually impaired sportswomen. However, there were no significant differences between the genders for optimism in the emotional intelligence questionnaire, and in mental toughness questionnaire. Conclusions: Visually impaired individuals pass through stages of emotional intelligence in a different way compared to those with normal vision. Moreover, motor skills and sports for the visually impaired are of a different kind. Moreover, our results showed that women benefited more from participating in physical and sporting activities than men did. Therefore, we recommend that authorities and people involved in sports for the visually impaired should make more use of exercises in psychological skills, along with technical and tactical ones, for visually impaired male

  13. Constructive Consumer Choice Processes.

    Bettman, James R; Luce, Mary Frances; Payne, John W

    1998-01-01

    Consumer decision making has been a focal interest in consumer research, and consideration of current marketplace trends ( e.g., technological change, an information explosion) indicates that this topic will continue to be critically important. We argue that consumer choice is inherently constructive. Due to limited processing capacity, consumers often do not have well-defined existing preferences, but construct them using a variety of strategies contingent on task demands. After describing c...

  14. A study on the fracture toughness of heavy section steel plates and forgings for nuclear pressure vessels produced in Japan, (4)

    Sakai, Yuzuru; Ogura, Nobukazu; Takahashi, Isao; Miya, Kenzo; Ando, Yoshio.

    1985-01-01

    As another parameter for evaluating the toughness of structural materials, there is crack arrest toughness. This is a parameter showing the resistance of materials to stop the cracks rapidly propagating in brittle state within the materials, unlike static and dynamic fracture toughness related to the occurrence of breaking. As the conventional method of determining the crack arrest toughness, the relatively large testing method such as double tensile test and ESSO test have been known, but the establishment of a smaller convenient testing method is desired. In this study, the evaluation of the crack arrest toughness of the very thick steel materials produced in Japan was carried out by the testing method using small test pieces. In order to make test pieces small, tapered type DCB test and the three-point bending test using DWTT test pieces were examined as well as the testing method recommended by ASTM. The test materials were A 533B, Cl. 1 and A 508, Cl. 3. The test pieces, the various testing methods and the experimental results are reported. The temperature dependence of the crack arrest toughness was shown. (Kako, I.)

  15. Microstructure and toughness of structural steels

    Chipperfield, C.G.; Knott, J.F.

    1975-01-01

    The effects of notch acuity, inclusion content, and strength level on the toughness of a variety of ductile steels have been investigated in fully plastic single edge notched bend testpieces. Results for specimens containing fatigue precracks and sharp notches indicate that accurate predictions of a material's resistance to the initiation of fibrous fracture ahead of a fatigue crack may be inferred from tests on notched testpieces and from a knowledge of the microstructure of the material; an experimental procedure has been proposed whereby this may be achieved for quality control and material evaluation purposes. The spacing of optically visible inclusions is found essentially to define both the unit of ductile crack extension and, for low-strength steels, the limiting lateral dimensions of the high-strain field ahead of the crack tip. As a consequence, the notch-tip ductility is found to be invariant with the changes in notch acuity for sharp stress concentrators. The effect of increasing the purity and/or strength level is to alter the mechanism of fibrous fracture from one involving void growth and coalescence to one of predominantly shear character. (author)

  16. Fracture toughness measurements on zirconia toughened ceramics

    El Sayed Ali, M.; Toft Soerensen, O.

    1986-12-01

    Three techniques for fracture toughness measurements on zirconia toughened ceramics were evaluated: the notched beam (NB) technique, the indentation fracture (IF) technique and the indentation strength in bending (ISB) technique. Using these techniques comparative measurements were performed on samples prepared by pressing (uniaxial) and sintering of four commercially available powder types. These were: Toya Soda (Japan) powders with the designations TZ3Y (2.86 mole% Y 2 O 3 ), TZ3YA (2.77 mole% Y 2 O 3 , 0.1 wt% Al 2 O 3 ) and TZ3Y20A (2.88 mole% Y 2 O 3 , 20 wt.% Al 2 O 3 ) and a powder supplied by Viking Chemicals (Denmark) designated as YP5Z-2.5 (2.5 mole% Y 2 O 3 ). The measurements showed that similar K Ic values were obtained with the IF- and ISB-techniques, which therefore are recommended for K Ic measurements. Too high values were, however, obtained with the NB-technique which therefore cannot be recommended. Finally, the measurements showed that a high temperature annealing is recommended prior to testing for the IF-technique. (author)

  17. Toughness behaviour of tungsten-carbide-cobalt alloys

    Sigl, L.S.

    1985-05-01

    In the present work the mechanisms of crack propagation in technically important WC-Co alloys are investigated and a model describing the influence of microstructural parameters and of the mechanical properties of the constituents is developed. An energy concept is used for modelling fracture toughness. The energies dissipated in the four crack-paths (trans- and intergranular carbide fracture, fracture across the binder-ligaments, fracture in the binder close to the carbide/binder interface) are summed up using the experimentally determined area-fractions of the crack-paths, the specific energy of brittle fracture in the carbide and of ductile fracture is calculated by integrating the energy to deform a volume element over the plastically deformed region. In contrast to all earlier models, this concept describes fracture toughness of WC-Co alloys only with physically meaningful parameters. The excellent agreement with experimental toughness values and with qualitative observations of crack propagation show that the new model includes all effects which influence toughness. As demonstrated with WC-based hardmetals with a cobalt-nickel binder, the results open new possibilities for optimizing the toughness of composites in which a small amount of a tough phase is embedded in a brittle matrix. (Author, shortened by G.Q.)

  18. Strength-toughness requirements for thick walled high pressure vessels

    Kapp, J.A.

    1990-01-01

    The strength and toughness requirements of materials for use in high pressure vessels has been the subject of some discussion in the meetings of the Materials Task Group of the Special Working Group High Pressure Vessels. A fracture mechanics analysis has been performed to theoretically establish the required toughness for a high pressure vessel. This paper reports that the analysis performed is based on the validity requirement for plane strain fracture of fracture toughness test specimens. This is that at the fracture event, the crack length, uncracked ligament, and vessel length must each be greater than fifty times the crack tip plastic zone size for brittle fracture to occur. For high pressure piping applications, the limiting physical dimension is the uncracked ligament, as it can be assumed that the other dimensions are always greater than fifty times the crack tip plastic zone. To perform the fracture mechanics analysis several parameters must be known: these include vessel dimensions, material strength, degree of autofrettage, and design pressure. Results of the analysis show, remarkably, that the effects of radius ratio, pressure and degree of autofrettage can be ignored when establishing strength and toughness requirements for code purposes. The only parameters that enter into the calculation are yield strength, toughness and vessel thickness. The final results can easily be represented as a graph of yield strength against toughness on which several curves, one for each vessel thickness, are plotted

  19. Fracture toughness of steel--aluminum deformation welds

    Albright, C.E.

    1978-11-01

    A study of the fracture toughness (in this case, G/sub Ic/) of steel--aluminum deformation welds using a specially developed double cantilever beam fracture toughness specimen is presented. Welds made at 350 0 C were heat treated at 360, 380, 400, 420, and 440 0 C. An intermetallic reaction product layer of Fe 2 Al 5 is formed at the steel--aluminum interface with increasing heat treating temperature and time by a process of nucleation and growth of discrete particles. A transition in toughness from a higher average G/sub Ic/ value (6097 N/m) to a very low average G/sub Ic/ value (525 N/m) is observed. The decrease in toughness is accompanied by an increase in Fe 2 Al 5 particle diameter from 4 to 8 μm. Failure at the higher toughness values is characterized by ductile rupture through the aluminum. At the lower toughness values, failure occurs between the aluminum and the Fe 2 Al 5 reaction product layer. A void layer forming by a vacancy condensation mechanism in the aluminum adjacent to the Fe 2 Al 5 is shown to cause the embrittlement

  20. Self-concept organisation and mental toughness in sport.

    Meggs, Jennifer; Ditzfeld, Christopher; Golby, Jim

    2014-01-01

    The present study examines the relationship between individual differences in evaluative self-organisation and mental toughness in sport, proposing that motivation and emotional resiliency (facets of mental toughness) stem from differences in core self. A cross-sectional assessment of 105 athletes competing at a range of performance levels took part in an online study including measures of self-reported mental toughness (Sport Mental Toughness Questionnaire; Sheard, M., Golby, J., & van Wersch, A. (2009). Progress towards construct validation of the Sports Mental Toughness Questionnaire (SMTQ). European Journal of Psychological Assessment, 25(3), 186-193. doi:10.1027/1015-5759.25.3.186) and self-organisation (self-descriptive attribute task; Showers, C. J. (2002). Integration and compartmentalisation: A model of self-structure and self-change. In D. Cervone & W. Mischel (Eds.), Advances in personality science (pp. 271-291). New York, NY: Guilford Press). As predicted, global mental toughness was associated with self-concept positivity, which was particularly high in individuals with positive-integrative self-organisation (individuals who distribute positive and negative self-attributes evenly across multiple selves). Specifically, positive integration was associated with constancy (commitment to goal achievement despite obstacles and the potential for failure), which extends presumably from positive integratives' emotional stability and drive to resolve negative self-beliefs.

  1. Toughness of the Virunga mountain gorilla (Gorilla beringei beringei) diet across an altitudinal gradient.

    Glowacka, Halszka; McFarlin, Shannon C; Vogel, Erin R; Stoinski, Tara S; Ndagijimana, Felix; Tuyisingize, Deo; Mudakikwa, Antoine; Schwartz, Gary T

    2017-08-01

    The robust masticatory system of mountain gorillas is thought to have evolved for the comminution of tough vegetation, yet, compared to other primates, the toughness of the mountain gorilla diet is unremarkable. This may be a result of low plant toughness in the mountain gorilla environment or of mountain gorillas feeding selectively on low-toughness foods. The goal of this paper is to determine how the toughness of the mountain gorilla diet varies across their habitat, which spans a large altitudinal range, and whether there is a relationship between toughness and food selection by mountain gorillas. We collected data on the following variables to determine whether, and if so how, they change with altitude: leaf toughness of two plant species consumed by mountain gorillas, at every 100 m increase in altitude (2,600-3,700 m); toughness of consumed foods comprising over 85% of the gorilla diet across five vegetation zones; and toughness of unconsumed/infrequently consumed plant parts of those foods. Although leaf toughness increased with altitude, the toughness of the gorilla diet remained similar. There was a negative relationship between toughness and consumption frequency, and toughness was a better predictor of consumption frequency than plant frequency, biomass, and density. Consumed plant parts were less tough than unconsumed/infrequently consumed parts and toughness of the latter increased with altitude. Although it is unclear whether gorillas select food based on toughness or use toughness as a sensory cue to impart other plant properties (e.g., macronutrients, chemicals), our results that gorillas maintain a consistent low-toughness dietary profile across altitude, despite toughness increasing with altitude, suggest that the robust gorilla masticatory apparatus evolved for repetitive mastication of foods that are not high in toughness. © 2017 Wiley Periodicals, Inc.

  2. Complex Strategic Choices

    Leleur, Steen

    to strategic decision making, Complex Strategic Choices presents a methodology which is further illustrated by a number of case studies and example applications. Dr. Techn. Steen Leleur has adapted previously established research based on feedback and input from various conferences, journals and students...... resulting in new material stemming from and focusing on practical application of a systemic approach. The outcome is a coherent and flexible approach named systemic planning. The inclusion of both the theoretical and practical aspects of systemic planning makes this book a key resource for researchers...

  3. Choice within Constraints: Mothers and Schooling.

    David, Miriam; Davies, Jackie; Edwards, Rosalind; Reay, Diane; Standing, Kay

    1997-01-01

    Explores, from a feminist perspective, the discourses of choice regarding how women make their choices as consumers in the education marketplace. It argues that mothers as parents are not free to choose but act within a range of constraints, i.e., their choices are limited by structural and moral possibilities in a patriarchal and racist society.…

  4. Analysis of inertial choice behaviour based expected and experienced savings from a real-world route choice experiment

    Vreeswijk, J.D.; Rakha, H.; Van Berkum, E.; Van Arem, B.

    2014-01-01

    In the context of route choice, inertial behaviour shows that drivers make choices that are satisfactory rather than optimal. Consequently, drivers may not necessarily alter their choice when confronted with a travel time increase on the current choice or a travel time decrease of a choice

  5. De controller als choice architect

    V.S. Maas (Victor)

    2012-01-01

    textabstractManagement accountants are choice architects: they provide information that is used in managerial decision making and they have considerable influence on the monetary and non-monetary incentives that drive managers’ decision-making processes. Over the past two decades, our know

  6. Commitment-based action: Rational choice theory and contrapreferential choice

    Radovanović Bojana

    2014-01-01

    Full Text Available This paper focuses on Sen’s concept of contrapreferential choice. Sen has developed this concept in order to overcome weaknesses of the rational choice theory. According to rational choice theory a decision-maker can be always seen as someone who maximises utility, and each choice he makes as the one that brings to him the highest level of personal wellbeing. Sen argues that in some situations we chose alternatives that bring us lower level of wellbeing than we could achieve if we had chosen some other alternative available to us. This happens when we base our decisions on moral principles, when we act out of duty. Sen calls such action a commitment-based action. When we act out of commitment we actually neglect our preferences and thus we make a contrapreferential choice, as Sen argues. This paper shows that, contrary to Sen, a commitment-based action can be explained within the framework of rational choice theory. However, when each choice we make can be explained within the framework of rational choice theory, when in everything we do maximisation principle can be loaded, then the variety of our motives and traits is lost, and the explanatory power of the rational choice theory is questionable. [Projekat Ministarstva nauke Republike Srbije, br. 47009: Evropske integracije i društveno-ekonomske promene privrede Srbije na putu ka EU i br. 179015: Izazovi i perspektive strukturnih promena u Srbiji: Strateški pravci ekonomskog razvoja i usklađivanje sa zahtevima EU

  7. Angelina′s choice

    Nishu Singh Goel

    2013-01-01

    Full Text Available This is an opinion piece on how a celebrity′s personal choice to undergo prophylactic mastectomy on discovery of an aberrant gene, when publicly promoted, carries in itself the power to influence and impact healthcare trends and decisions. When celebrities advocate causes that are universally and uniformly acceptable and indisputable as the best in the realm of healthcare and cure (e.g. no smoking, it creates well-being and awareness in society at large. But those which are personal choices made out of a repertoire of other available and effective options may, because of celebrity preference, don the mantle of a norm. They thus run the danger of being blindly replicated by others without proper awareness and knowledge of the true potential of disease, risk factors, and other existing remedial or risk-reducing measures. Society should thus be encouraged to question, debate, and understand the validity, authenticity, and reason of the choices, especially those with a medical basis. This tempering of information with intelligence and rationale and making informed choices based on facts will serve humanity as a whole.

  8. Making Choices about Everyday Care (for Families)

    ... be alone most of the time or have company? Communicating Your Wishes Both the one who is ... and living arrangements, before problems arise or a crisis occurs. The sooner you discuss such questions, the ...

  9. Making Research Cyberinfrastructure a Strategic Choice

    Hacker, Thomas J.; Wheeler, Bradley C.

    2007-01-01

    The commoditization of low-cost hardware has enabled even modest-sized laboratories and research projects to own their own "supercomputers." The authors argue that this local solution undermines rather than amplifies the research potential of scholars. CIOs, provosts, and research technologists should consider carefully an overall…

  10. White Arctic vs. Blue Arctic: Making Choices

    Pfirman, S. L.; Newton, R.; Schlosser, P.; Pomerance, R.; Tremblay, B.; Murray, M. S.; Gerrard, M.

    2015-12-01

    As the Arctic warms and shifts from icy white to watery blue and resource-rich, tension is arising between the desire to restore and sustain an ice-covered Arctic and stakeholder communities that hope to benefit from an open Arctic Ocean. If emissions of greenhouse gases to the atmosphere continue on their present trend, most of the summer sea ice cover is projected to be gone by mid-century, i.e., by the time that few if any interventions could be in place to restore it. There are many local as well as global reasons for ice restoration, including for example, preserving the Arctic's reflectivity, sustaining critical habitat, and maintaining cultural traditions. However, due to challenges in implementing interventions, it may take decades before summer sea ice would begin to return. This means that future generations would be faced with bringing sea ice back into regions where they have not experienced it before. While there is likely to be interest in taking action to restore ice for the local, regional, and global services it provides, there is also interest in the economic advancement that open access brings. Dealing with these emerging issues and new combinations of stakeholders needs new approaches - yet environmental change in the Arctic is proceeding quickly and will force the issues sooner rather than later. In this contribution we examine challenges, opportunities, and responsibilities related to exploring options for restoring Arctic sea ice and potential pathways for their implementation. Negotiating responses involves international strategic considerations including security and governance, meaning that along with local communities, state decision-makers, and commercial interests, national governments will have to play central roles. While these issues are currently playing out in the Arctic, similar tensions are also emerging in other regions.

  11. Creating Healthy Habits: Make Better Choices Easier

    ... O'Donnell S, Oluyomi DT, Epstein LH. Consciousness and Cognition. 2017 May;51:10-16. doi: 10.1016/ ... Editor: Tianna Hicklin, Ph.D. Illustrator: Alan Defibaugh Attention Editors: Reprint our articles and illustrations in your ...

  12. Protect Your Heart: Make Smart Food Choices

    ... blood vessels. • Eat more vegetables and fruit. J Eat at least one vegetable or a salad at lunch and dinner. Snack on raw vegetables. J Try new ways of cooking vegetables, such as steaming, stir-frying, or roasting. J Eat dark green and dark yellow vegetables every day, ...

  13. Therapeutic radionuclides: Making the right choice

    Srivastava, S.C.

    1996-01-01

    Recently, there has been a resurgence of interest in nuclear medicine therapeutic procedures. Using unsealed sources for therapy is not a new concept; it has been around since the beginnings of nuclear medicine. Treatment of thyroid disorders with radioiodine is a classic example. The availability of radionuclides with suitable therapeutic properties for specific applications, as well as methods for their selective targeting to diseased tissue have, however, remained the main obstacles for therapy to assume a more widespread role in nuclear medicine. Nonetheless, a number of new techniques that have recently emerged, (e.g., tumor therapy with radiolabeled monoclonal antibodies, treatment of metastatic bone pain, etc.) appear to have provided a substantial impetus to research on production of new therapeutic radionuclides. Although there are a number of new therapeutic approaches requiring specific radionuclides, only selected broad areas will be used as examples in this article

  14. The VMAT-2 inhibitor tetrabenazine alters effort-related decision making as measured by the T-maze barrier choice task: reversal with the adenosine A2A antagonist MSX-3 and the catecholamine uptake blocker bupropion.

    Yohn, Samantha E; Thompson, Christian; Randall, Patrick A; Lee, Christie A; Müller, Christa E; Baqi, Younis; Correa, Mercè; Salamone, John D

    2015-04-01

    Depressed people show effort-related motivational symptoms, such as anergia, retardation, lassitude, and fatigue. Animal tests can model these motivational symptoms, and the present studies characterized the effort-related effects of the vesicular monoamine transport (VMAT-2) inhibitor tetrabenazine. Tetrabenazine produces depressive symptoms in humans and, at low doses, preferentially depletes dopamine. The current studies investigated the effects of tetrabenazine on effort-based decision making using the T-maze barrier task. Rats were tested in a T-maze in which the choice arms of the maze contain different reinforcement densities, and under some conditions, a vertical barrier was placed in the high-density arm to provide an effort-related challenge. The first experiment assessed the effects of tetrabenazine under different maze conditions: a barrier in the arm with 4 food pellets and 2 pellets in the no barrier arm (4-2 barrier), 4 pellets in one arm and 2 pellets in the other with no barrier in either arm (no barrier), and 4 pellets in the barrier arm with no pellets in the other (4-0 barrier). Tetrabenazine (0.25-0.75 mg/kg IP) decreased selection of the high cost/high reward arm when the barrier was present, but had no effect on choice under the no barrier and 4-0 barrier conditions. The effects of tetrabenazine on barrier climbing in the 4-2 condition were reversed by the adenosine A2A antagonist MSX-3 and the catecholamine uptake inhibitor and antidepressant bupropion. These studies have implications for the development of animal models of the motivational symptoms of depression and other disorders.

  15. Fracture toughness of dentin/resin-composite adhesive interfaces.

    Tam, L E; Pilliar, R M

    1993-05-01

    The reliability and validity of tensile and shear bond strength determinations of dentin-bonded interfaces have been questioned. The fracture toughness value (KIC) reflects the ability of a material to resist crack initiation and unstable propagation. When applied to an adhesive interface, it should account for both interfacial bond strength and inherent defects at or near the interface, and should therefore be more appropriate for characterization of interface fracture resistance. This study introduced a fracture toughness test for the assessment of dentin/resin-composite bonded interfaces. The miniature short-rod specimen geometry was used for fracture toughness testing. Each specimen contained a tooth slice, sectioned from a bovine incisor, to form the bonded interface. The fracture toughness of an enamel-bonded interface was assessed in addition to the dentin-bonded interfaces. Tensile bond strength specimens were also prepared from the dentin surfaces of the cut bovine incisors. A minimum of ten specimens was fabricated for each group of materials tested. After the specimens were aged for 24 h in distilled water at 37 degrees C, the specimens were loaded to failure in an Instron universal testing machine. There were significant differences (p adhesives tested. Generally, both the fracture toughness and tensile bond strength measurements were highest for AllBond 2, intermediate for 3M MultiPurpose, and lowest for Scotchbond 2. Scanning electron microscopy of the fractured specimen halves confirmed that crack propagation occurred along the bond interface during the fracture toughness test. It was therefore concluded that the mini-short-rod fracture toughness test provided a valid method for characterization of the fracture resistance of the dentin-resin composite interface.

  16. Effect of Mn on σ Phase and Toughness of 22%Cr Duplex Stainless Steel by Aging Treatment at 700℃

    BAI Yu-liang

    2017-05-01

    Full Text Available The effect of different Mn contents on the σ phase and toughness of 22%Cr (mass fraction, the same below low-nickel DSS by means of OM, XRD, SEM, TEM, precipitation kinetics and Charpy impact tests was studied. The results show that the morphology of precipitated phases changes from tiny granulated σ phase in δ/γ phase boundary to σ/γ2 eutectoid structure within δ phase with the addition of Mn from 4.3% to 9.7% and 76 hours aging. The increase of Mn content can decrease Avrami exponent n and increase reaction constant B, and the accelerating of σ-phase precipitation with higher Mn addition is due to the participation of Mn. Increasing Mn content can make initial time and ending time of σ-phase precipitation earlier and expand the interval between the initial time and ending time of σ-phase precipitation, that is, the more Mn addition, the earlier precipitation beginning time of σ-phase and the lower precipitation rate of it. The impact toughness is not sensitive to 1% transformation fraction of δ-ferrite, but it drops rapidly while the transformation fraction of δ-ferrite increases from 1% to 5%. More addition of Mn is good to impact toughness at the early stage of aging treatment, but the impact toughness decreases rapidly by accelerating the transformation fraction of δ-ferrite more than 1% earlier at the middle stage of aging time.

  17. Effect of Temperature on the Toughness of Locally Manufactured Low Alloy Steel SUP9 Used for Manufacturing Leaf Springs

    Muhammad Ishaque Abro

    2011-10-01

    Full Text Available The effect of heat treatment on locally manufactured low alloy steel grade SUP9 most frequently used in making leaf springs for automobiles was studied. While for determination of toughness and hardness Charpy impact testing machine and Rockwell hardness tester were used. The cryogenic test temperatures were achieved by soaking the samples in liquid nitrogen and temperature was measured using digital thermometer capable of reading the temperature from -40-200oC. Hardening, tempering and austempering treatments were conducted using muffle furnace and salt bath furnace. After heat treatment samples were quenched in oil. The results of present work confirmed that toughness and hardness are inversely related with each other and are highly dependent on the type of heat treatment employed. Highest toughness was measured after austempering at 450oC. Effect of test temperature revealed that toughness of the samples increased significantly with decreasing temperature. DBTT (Ductile to Brittle Transition Temperature of the austempered samples was observed at -10oC, whereas, that of tempered samples could not be determined. Based on the test results authors wish to recommend the 600oC tempering temperature in place of 450oC where normally tempering is practiced in Alwin industry Karachi during manufacturing of leaf spring.

  18. Visible Light Photoinitiator for 3D-Printing of Tough Methacrylate Resins

    Bernhard Steyrer

    2017-12-01

    Full Text Available Lithography-based additive manufacturing was introduced in the 1980s, and is still the method of choice for printing accurate plastic parts with high surface quality. Recent progress in this field has made tough photopolymer resins and cheap LED light engines available. This study presents the influence of photoinitiator selection and post-processing on the thermomechanical properties of various tough photopolymers. The influence of three photoinitiators (Ivocerin, BAPO, and TPO-L on the double-bond conversion and mechanical properties was investigated by mid infrared spectroscopy, dynamic mechanical analysis and tensile tests. It was found that 1.18 wt % TPO-L would provide the best overall results in terms of double-bond conversion and mechanical properties. A correlation between double-bond conversion, yield strength, and glass transition temperature was found. Elongation at break remained high after post-curing at about 80–100%, and was not influenced by higher photoinitiator concentration. Finally, functional parts with 41 MPa tensile strength, 82% elongation at break, and 112 °C glass transition temperature were printed on a 405 nm DLP (digital light processing printer.

  19. Choice as an engine of analytic thought.

    Savani, Krishna; Stephens, Nicole M; Markus, Hazel Rose

    2017-09-01

    Choice is a behavioral act that has a variety of well-documented motivational consequences-it fosters independence by allowing people to simultaneously express themselves and influence the environment. Given the link between independence and analytic thinking, the current research tested whether choice also leads people to think in a more analytic rather than holistic manner. Four experiments demonstrate that making choices, recalling choices, and viewing others make choices leads people to think more analytically, as indicated by their attitudes, perceptual judgments, categorization, and patterns of attention allocation. People who made choices scored higher on a subjective self-report measure of analytic cognition compared to whose did not make a choice (pilot study). Using an objective task-based measure, people who recalled choices rather than actions were less influenced by changes in the background when making judgments about focal objects (Experiment 1). People who thought of others' behaviors as choices rather than actions were more likely to group objects based on categories rather than relationships (Experiment 2). People who recalled choices rather than actions subsequently allocated more visual attention to focal objects in a scene (Experiment 3). Together, these experiments demonstrate that choice has important yet previously unexamined consequences for basic psychological processes such as attention and cognition. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  20. Mental Toughness Attributes of Junior Level Medalist Badminton Players

    Varghese C. Antony

    2016-10-01

    Full Text Available The study aims to compare the mental toughness attributes between medalist and non-medalist badminton players and between male and female players. Participants were 15 male and 15 female badminton players aged between 13-19 years (M= 15.71, SD=2.82. Mental toughness questionnaire of Tiwari and Sharma was administered and the data were analyzed by using descriptive statistics and t-test. Medalist players have exhibited higher mean values on self-confidence, attention control, motivation and goal setting attributes. Overall mental toughness of medalists was higher 180.80±17.15 than non-medalists 170.25±20.10. Comparison analysis showed significant difference between medalists and non-medalists on mental toughness attributes: Self-confidence (SCO: p=0.001<0.05, medalists scored (M±SD=31.33±2.10 higher than non-medalists; motivation (MOT: p=0.006<0.05, medalist scored higher (M±SD=33.50±4.07; goal setting (GSE: p=0.044<0.05, medalists scored significantly higher (M±SD=33.55±4.11 than non-medalists. Other attributes did not show any significant difference between medalist and non-medalist players. When compared with gender, no significant difference was observed on mental toughness attributes except attention control (ATNCON: p=0.044<0.05, female players scored (M±SD=38.97±3.08 higher than male players. The findings confirm that mental toughness is a desired attribute which differentiates a medalist and non-medalist player. Connaughton et al., (2007 stated that elite competitive athletes possess better mental toughness. Medalist players displayed better self-confidence than the non-medalists as supported by Kuan and Roy (2007, Loehr (1986. Motivation helps players to achieve their best and enhance mental toughness (Connaughton et al., 2008; Mohammad et al., 2009. Goal setting determines successful performance Weinberg and Weigand (1993, Weinberg (2003. It was concluded that medalist badminton players showed better mental toughness

  1. High-temperature fracture toughness of duplex microstructures

    French, J.D.; Chan, H.M.; Harmer, M.P.; Miller, G.A.

    1996-01-01

    The temperature dependence of the fracture toughness of ceramics exhibiting duplex microstructures was studied relative to their single-phase constituents using two test methods: bend testing of chevron-notched beams, and the indentation-crack-length technique. The two materials systems studied were Al 2 O 3 :c-ZrO 2 (Y) and Al 2 O 3 :Y 3 Al 5 O 12 (YAG), and the testing temperature ranged from room temperature to 1,200 C. The study showed that in both systems the duplex materials showed higher toughness values than their single-phase constituents above 800 C. This result was attributed to the contribution of low-energy interphase boundaries to the overall composite toughness. Indentation crack length measurements gave toughness values and trends comparable to those determined by the chevron-notched beam method. By comparing the results of the two test methods it was possible to demonstrate that the indentation calibration constant (ξ) shows no significant temperature or material dependence. For the zirconia-containing materials, however, indentation at elevated temperatures is accompanied by significant localized plasticity, which suppressed the radial cracking. Under such conditions, some caution is warranted, since localized plasticity can lead to an overestimation of the fracture toughness

  2. A New Method for Evaluating the Indentation Toughness of Hardmetals

    Prem C. Jindal

    2018-05-01

    Full Text Available This paper proposes a new method of evaluating the indentation toughness of hardmetals using the length of Palmqvist cracks (C and Vickers indentation diagonal size (di. Indentation load “P” is divided into two parts: Pi for plastic indentation size and Pc for Palmqvist cracks. Pi depends upon the square of the indentation size (di2 and Pc depends upon (C3/2. The new method produces a very good linear relationship between the calculated indentation toughness values and the standard conventional linear elastic fracture mechanics toughness values with the same cemented carbide materials for a large number of standard Kennametal grades for both straight WC-Co carbide grades and grades containing cubic carbides. The new method also works on WC-Co hardmetal data selected from recently published literature. The technique compares the indentation toughness values of WC-Co materials before and after vacuum annealing at high temperature. The indentation toughness values of annealed carbide samples were lower than for un-annealed WC-Co hardmetals.

  3. An evaluation of fracture toughness of bituminous coal

    Pathan, A.G.

    2005-01-01

    The role of fracture mechanics in the design of rock structures is vitally important. However, because of the complexities of rock structures and lack of understanding of the fundamentals of the failure mechanism, it has become customary to use the engineering properties approach in the design of stable rock structures. Recently considerable attention has been given and attempts are being made to apply the fracture mechanics approach to the design of safe mining structures. In mining engineering the fracture mechanics may be applied to calculate the formation of fracture zones around mine opening, thus estimating support requirements and formulating guide lines for the selection of mine roadway support system. The research work presented here is concerned with the evaluation of fracture toughness of coal under laboratory conditions. Diametral compression test method is used to determine the fracture toughness parameter of coal in the opening model failure. The effect of crack length and dimensionless crack length on the fracture toughness was studied also. A laboratory investigation of fracture toughness of coal in tensile mode failure has led to the conclusion that fracture toughness could be treated as a material property. (author)

  4. Fracture toughness properties of similar and dissimilar electron beam welds

    Kocak, M.; Junghans, E.

    1994-01-01

    The weldability aspects, tensile and Crack Tip Opening Displacement (CTOD) toughness properties of 9Cr1MoNbV (P91) martensitic steel with austenitic 316L steel were evaluated for electron beam (EB) welds on 35 mm thick pates. The effects of mechanical heterogeneity (mis-matching) at the vicinity of the crack tip of dissimilar three point bend specimens on the CTOD fracture toughness values was also discussed. The CTOD tests were performed on similar and dissimilar EB welds of austenitic and tempered martensitic P91 steels at room temperature. Dilution of austenitic with martensitic steel resulted in predominantly martensitic EB weld metal, exhibiting rather high yield strength and hardness. Nevertheless, the weld metal produced high CTOD toughness values due to the beneficial effect of the lower strength austenitic steel part of the specimen in which crack deviation occured (mis-match effect). The coarse grained HAZ of the P91 steel side exhibits extremely poor CTOD toughness properties in the as-welded condition at room temperature. The CTOD values obtained are believed to be representing the intrinsic property of this zone since the distance of the crack tip to the weaker austenitic steel part of the SENB specimens was too large to cause an effective stress relaxation at the crack tip. Further post weld heat treatment at 750 C for two hours improved the CTOD toughness marginally. (orig.)

  5. Fracture toughness of intermetallics using a micro-mechanical probe

    Gerberich, W.W.; Venkataraman, S.K.; Hoehn, J.W.; Marsh, P.G.

    1993-01-01

    A novel technique for determining the fracture toughness of brittle intermetallics is presented, wherein very small samples are used and multiple tests are easily conducted on a flat polished surface. The fracture toughness of single crystal NiAl and polycrystalline Al 3 Sc are evaluated with this continuous microscratch technique at scratch rates ranging from 0.5 to greater than 100 μm s - . For comparison, small compact tension samples of (100) NiAl are evaluated at applied stress intensity rates ranging from 1.5 to 5,400 MPa-m 1/2 s -1 . Good comparison of microscratch toughness to compact tension K Ic values are obtained in this study for (001) NiAl, 10.6 vs. 10.0 MPa-m 1/2 , from the literature for (001) , 13.5 vs. 12.2 MPa-m 1/2 , and from the literature for polycrystalline Al 3 Sc, 3.5 vs. 3.1 MPa-m 1/2 . Also, the fracture toughness of both NiAl and Al 3 Sc are found to be strongly dependent on strain rate at room temperature with toughness dropping by an order of magnitude over a decade increase in rate. Possible reasons and implications to improving low temperature brittleness are discussed

  6. Fracture toughness evaluation of Eurofer'97 by testing small specimens

    Serrano, M.; Fernandez, P.; Lapena, J.

    2006-01-01

    The Eurofer'97 is the structural reference material that will be tested in the ITER modules. Its metallurgical properties have been well characterized during the last years. However, more investigations related with the fracture toughness of this material are necessary because this property is one of the most important to design structural components and to study their integrity assessment. In the case of structural materials for fusion reactor the small specimen technology (SSTT) are being actively developed to investigate the fracture toughness among other mechanical properties. The use of small specimens is due to the small available irradiation volume of IFMIF and also due to the high fluence expected in the fusion reactor. The aim of this paper is to determine the fracture toughness of the Eurofer'97 steel by testing small specimens of different geometry in the ductile to brittle transition region, with the application of the Master Curve methodology, and to evaluate this method to assess the decrease in fracture toughness due to neutron irradiation. The tests and data analysis have been performed following the Master Curve approach included in the ASTM Standard E1921-05. Specimen size effect and comparison of the fracture toughness results with data available in the literature are also considered. (author)

  7. Fracture toughness evaluations of TP304 stainless steel pipes

    Rudland, D.L.; Brust, F.W.; Wilkowski, G.M.

    1997-02-01

    In the IPIRG-1 program, the J-R curve calculated for a 16-inch nominal diameter, Schedule 100 TP304 stainless steel (DP2-A8) surface-cracked pipe experiment (Experiment 1.3-3) was considerably lower than the quasi-static, monotonic J-R curve calculated from a C(T) specimen (A8-12a). The results from several related investigations conducted to determine the cause of the observed toughness difference are: (1) chemical analyses on sections of Pipe DP2-A8 from several surface-cracked pipe and material property specimen fracture surfaces indicate that there are two distinct heats of material within Pipe DP2-A8 that differ in chemical composition; (2) SEN(T) specimen experimental results indicate that the toughness of a surface-cracked specimen is highly dependent on the depth of the initial crack, in addition, the J-R curves from the SEN(T) specimens closely match the J-R curve from the surface-cracked pipe experiment; (3) C(T) experimental results suggest that there is a large difference in the quasi-static, monotonic toughness between the two heats of DP2-A8, as well as a toughness degradation in the lower toughness heat of material (DP2-A8II) when loaded with a dynamic, cyclic (R = -0.3) loading history

  8. Macro-Choices, Micro-Choosers

    MOSAIC, 1975

    1975-01-01

    The ways in which the world produces, distributes, and consumes its food are as varied as the small societies with which the world's growing billions most closely identify. Making food choices for the world means first understanding the myriad ways in which the world's microcultures make choices for themselves. (BT)

  9. De controller als choice architect

    Maas, V.S.

    2012-01-01

    textabstractManagement accountants are choice architects: they provide information that is used in managerial decision making and they have considerable influence on the monetary and non-monetary incentives that drive managers’ decision-making processes. Over the past two decades, our know - ledge of how people make economic decisions has increased tremendously. However, this has had only very little impact on the design of management accounting and control systems in organizations. Consequen...

  10. Attention and choice

    Orquin, Jacob Lund; Mueller Loose, Simone

    2013-01-01

    satisfaction models. Although most theories were confirmed with regard to certain predictions, none of the theories adequately accounted for the role of attention during decision making. Several observations emerged concerning the drivers and down-stream effects of attention on choice, suggesting......This paper reviews studies on eye movements in decision making, and compares their observations to theoretical predictions concerning the role of attention in decision making. Four decision theories are examined: rational models, bounded rationality, evidence accumulation, and parallel constraint...... that attention processes plays an active role in constructing decisions. So far, decision theories have largely ignored the constructive role of attention by assuming that it is entirely determined by heuristics, or that it consists of stochastic information sampling. The empirical observations reveal...

  11. That tough guy from Nazareth: A psychological assessment of Jesus

    J. Harold Ellens

    2014-03-01

    Full Text Available Christmas gives us that ’sweet little Jesus Boy’ and Lent follows that with the ‘gentle Jesus, meek and mild.’ He was neither of those. In point of fact, he was the ‘tough guy from Nazareth.’ He was consistently abrasive, if not abusive, to his mother (Lk 2:49; Jn 2:4; Mt 12:48 and aggressively hard on males, particularly those in authority. In Mark 8 he cursed and damned Peter for failing to get Jesus’ esoteric definition of Messiah correct. Nobody else understood it either. Jesus had made it up himself and not adequately explained it to anybody until then. He called the religious authorities snakes, corrupt tombs, filthy chinaware, fakes, and Mosaic legalists who had forgotten God’s real revelation of universal grace and salvation in the Abraham Covenant. He tore up the temple in the middle of a worship service and cursed those present for turning God’s house of prayer into a den of thieves, when actually they were kind, helping out-of-town tourists obtain the proper sacrifices for the liturgical rituals. Jesus was persistently aggressive, often angry and not infrequently irrational, killing an innocent fig tree with his curse, for example. He constantly attacked the Pharisees and their proposals for renewing the spiritual vitality of the Jewish Community. He abused numerous people by healing them on the Sabbath just to make his political point against the religious leaders. He could just as well have healed them on Tuesday, if he really wanted to heal them. By healing the blind man in John 9 on the Sabbath, for example, he caused the man to be driven out of his synagogue, his family, and his community of faith; isolated and abandoned as if he were a leper. Even when he said surprising things about children, his focus was not on the children but on his disciples, using the children as tools for making an assertive teaching point. Jesus’ life was one of perpetually aggressive claims for his vision of God’s reign. He

  12. Fracture toughness of borides formed on boronized ductile iron

    Sen, Ugur; Sen, Saduman; Koksal, Sakip; Yilmaz, Fevzi

    2005-01-01

    In this study, fracture toughness properties of boronized ductile iron were investigated. Boronizing was realized in a salt bath consisting of borax, boric acid and ferro-silicon. Boronizing heat treatment was carried out between 850 and 950 deg. C under the atmospheric pressure for 2-8 h. Borides e.g. FeB, Fe 2 B formed on ductile iron was verified by X-ray diffraction (XRD) analysis, SEM and optical microscope. Experimental results revealed that longer boronizing time resulted in thicker boride layers. Optical microscope cross-sectional observation of borided layers showed dentricular morphology. Both microhardness and fracture toughness of borided surfaces were measured via Vickers indenter. The harnesses of borides formed on the ductile iron were in the range of 1160-2140 HV 0.1 and fracture toughness were in the range of 2.19-4.47 MPa m 1/2 depending on boronizing time and temperature

  13. Influence of texture on fracture toughness of zircaloy cladding

    Grigoriev, V.; Andersson, Stefan

    1997-06-01

    The correlation between texture and fracture toughness of Zircaloy 2 cladding has been investigated in connection with axial cracks in fuel rods. The texture of the cladding determines the anisotropy of plasticity of the cladding which, in turn, should influence the strain conditions at the crack-tip. Plastic strains in the cladding under uniaxial tension were characterised by means of the anisotropy constants F, G and H calculated according to Hill's theory. Test temperatures between 20 and 300 deg C do not influence the F, G and H values. Any significant effect of hydrogen (about 500 wtppm) on the anisotropy constants F, G and H has not been revealed at a test temperature of 300 deg C. The results, obtained for stress-relieved and recrystallized cladding with different texture, show an obvious influence of texture on the fracture toughness of Zircaloy cladding. A higher fracture toughness has been found for cladding with more radial texture

  14. The effect of specimen and flaw dimensions on fracture toughness

    Nevalainen, M.J. [VTT Manufacturing Technology, Espoo (Finland)

    1997-06-01

    The effect of the specimen size and geometry on fracture toughness has been investigated both by experimental tests and computational analyses. The methods for constraint description, namely T-stress, Q-parameter and Small-Scale Yielding Correction (SSYC) have been compared and applied for various geometries. A statistical treatment for the specimen thickness effect on cleavage fracture toughness has been investigated. Elliptical surface cracks were compared with straight-thickness cracks and a method for crack shape correction was presented. Based on the results, the differences in apparent fracture toughness values obtained from various specimen configurations can be better understood and taken into account. 64 refs. The thesis includes also four previous publications by author.

  15. The crack layer approach to toughness characterization in steel

    Bessendorff, M.; Chudnovsky, A.

    1986-01-01

    In a study of the laws of crack propagation and toughness characterization, it is feasible to employ two alternative approaches, including the fracture mechanics approach and the material science approach. The crack layer (CL) theory discussed by Khandogin and Chudnovsky (1978) and Chudnovsky (1980) considers the crack together with the surrounding defects as one system which has several degrees of freedom. It is pointed out that the CL theory defines the relationship between the parameters of fracture mechanics and the characteristics of microstructural changes which are the subject of material science. Experiments are described, taking into account a toughness characterization test and microscopic studies. Attention is given to a phenomenological study of toughness characterization, the morphology of crack layer, and the evaluation of energy stored in the dislocation network.

  16. Effect of microstructure evolution of the lamellar alpha on impact toughness in a two-phase titanium alloy

    Xu, Jianwei; Zeng, Weidong; Zhao, Yawei; Jia, Zhiqiang

    2016-01-01

    The effects of the evolution of the lamellar alpha microstructure on the impact toughness of Ti-17 alloy are investigated. For this purpose, the beta-processed material is isothermally forged at 820 °C and subsequently heat treated using the combination of solid solution and aging treatment. Then the impact tests are carried out at room temperature. The corresponding microstructure and fracture surface are examined by scanning electron microscope (SEM). Microstructural observations reveal that globularization behavior is the main feature of microstructure evolution and the globularization fraction increases with the increasing of prestrain. However, globularization behavior has a negative influence on the impact toughness of Ti-17 alloy. In this work, the impact toughness have been obtained in the range of 29–55 J/cm 2 via varying globularization fraction of alpha phase. A linear relationship between the impact toughness and globularization fraction can be observed though the quantitative analysis. The linear equation is expressed as A=−0.3232f+59.885. The two major reasons can be used to explain the effect of globularization fraction on the impact property of Ti-17 alloy. One explanation is that the lamellar structure can provide excellent interfacial strengthening effect, which can improve the toughness of material, and makes it not easy to fracture. On the other hand, the fracture surface of specimen with the lamellar structure has larger amplitude of ups and downs. A long crack path length will be generated during fracture process. By contrast, the fracture of specimen with the equiaxed structure presents more flat surface and shorter crack path.

  17. TOUGH2 User's Guide Version 2

    Pruess, K.; Oldenburg, C.M.; Moridis, G.J.

    1999-11-01

    TOUGH2 is a numerical simulator for nonisothermal flows of multicomponent, multiphase fluids in one, two, and three-dimensional porous and fractured media. The chief applications for which TOUGH2 is designed are in geothermal reservoir engineering, nuclear waste disposal, environmental assessment and remediation, and unsaturated and saturated zone hydrology. TOUGH2 was first released to the public in 1991; the 1991 code was updated in 1994 when a set of preconditioned conjugate gradient solvers was added to allow a more efficient solution of large problems. The current Version 2.0 features several new fluid property modules and offers enhanced process modeling capabilities, such as coupled reservoir-wellbore flow, precipitation and dissolution effects, and multiphase diffusion. Numerous improvements in previously released modules have been made and new user features have been added, such as enhanced linear equation solvers, and writing of graphics files. The T2VOC module for three-phase flows of water, air and a volatile organic chemical (VOC), and the T2DM module for hydrodynamic dispersion in 2-D flow systems have been integrated into the overall structure of the code and are included in the Version 2.0 package. Data inputs are upwardly compatible with the previous version. Coding changes were generally kept to a minimum, and were only made as needed to achieve the additional functionalities desired. TOUGH2 is written in standard FORTRAN77 and can be run on any platform, such as workstations, PCs, Macintosh, mainframe and supercomputers, for which appropriate FORTRAN compilers are available. This report is a self-contained guide to application of TOUGH2 to subsurface flow problems. It gives a technical description of the TOUGH2 code, including a discussion of the physical processes modeled, and the mathematical and numerical methods used. Illustrative sample problems are presented along with detailed instructions for preparing input data.

  18. Fracture Toughness of Ceramics Fired at Different Temperatures

    Peter SIN

    2012-03-01

    Full Text Available The fracture toughness test was performed at room temperature on sets of 5 ceramic samples made from material for high voltage insulators (kaolin 36 wt. %, Al2O3 30 wt. %, clay 12 wt. % and feldspar 22 wt. % fired at temperatures 400, 500, 600, 700, 800, 900, 1000, 1100, 1200, 1250, 1300, 1400, 1500 °C at heating and cooling rate of 5 °C/min. The precrack was made to each sample by indentation under the loads 10 N – 200 N, the dwell time was 45 s and the loading rate was 10 N/s. Results of the fracture toughness tests were in accordance with changes of structure of the samples after the partial firings. Fracture toughness from 20 °C to 500 °C is almost constant and it varies between 0.1 MPa·m0.5and 0.2 MPa·m0.5. Dehydroxylation (420 °C – 600 °C does not influence the value of fracture toughness. At temperature interval where we assume sintering (700 °C – 1250 °C we observe exponential dependence of fracture toughness up to 1.5 MPa·m0.5. From comparison of the fracture toughness, Young’s modulus and flexural strength follows a correlation and proporcionality of these mechanical properties.DOI: http://dx.doi.org/10.5755/j01.ms.18.1.1349

  19. Tough hybrid ceramic-based material with high strength

    Guo, Shuqi; Kagawa, Yutaka; Nishimura, Toshiyuki

    2012-01-01

    This study describes a tough and strong hybrid ceramic material consisting of platelet-like zirconium compounds and metal. A mixture of boron carbide and excess zirconium powder was heated to 1900 °C using a liquid-phase reaction sintering technique to produce a platelet-like ZrB 2 -based hybrid ceramic bonded by a thin zirconium layer. The platelet-like ZrB 2 grains were randomly present in the as-sintered hybrid ceramic. Relative to non-hybrid ceramics, the fracture toughness and flexural strength of the hybrid ceramic increased by approximately 2-fold.

  20. Overconfidence and Career Choice.

    Schulz, Jonathan F; Thöni, Christian

    2016-01-01

    People self-assess their relative ability when making career choices. Thus, confidence in their own abilities is likely an important factor for selection into various career paths. In a sample of 711 first-year students we examine whether there are systematic differences in confidence levels across fields of study. We find that our experimental confidence measures significantly vary between fields of study: While students in business related academic disciplines (Political Science, Law, Economics, and Business Administration) exhibit the highest confidence levels, students of Humanities range at the other end of the scale. This may have important implications for subsequent earnings and professions students select themselves in.

  1. Overconfidence and Career Choice

    Schulz, Jonathan F.; Thöni, Christian

    2016-01-01

    People self-assess their relative ability when making career choices. Thus, confidence in their own abilities is likely an important factor for selection into various career paths. In a sample of 711 first-year students we examine whether there are systematic differences in confidence levels across fields of study. We find that our experimental confidence measures significantly vary between fields of study: While students in business related academic disciplines (Political Science, Law, Economics, and Business Administration) exhibit the highest confidence levels, students of Humanities range at the other end of the scale. This may have important implications for subsequent earnings and professions students select themselves in. PMID:26808273

  2. Tough Times Ahead for Government Labs

    Ban, Stephen; Buchanan, Michelle V.; Cheeks, Nona; Funsten, Herbert; Hawsey, Robert; Lane, Monya; Whitlow, Woodrow Jr.; Studt, Tim

    2008-01-01

    Many government R and D laboratory executives face a tough couple of months ahead. These anxieties are fueled by (1) possible management, technical direction, and budgetary changes in their agencies due to changes in the federal administration; (2) frozen operating budgets until March 2009 due to the Continuing Resolution (CR) attachment to the recent banking bailout bill; and (3) the financial fallout from the economic downturn. These and other pertinent questions regarding their R and D operations were addressed in R and D Magazine's 9th Annual Government R and D Executive Roundtable held on Oct. 16, 2008, in conjunction with the 46th Annual R and D 100 Awards at Chicago's Navy Pier. Most members of this year's government executive panel were hesitant to speculate on the changes that might occur in their labs as a result of the new administration. The exception to this stand was the National Renewable Energy Laboratory's (NREL's) Robert Hawsey. ''No matter who wins (the Roundtable was held before the Nov. 4th Presidential election), we expect to see continued support,'' says Hawsey. ''All of our cooperative research facilities are over-subscribed and we're looking at how we can expand them.'' Obviously, renewable energy is a hot button in the administration and likely to get increased financial backing to help meet our country's energy independence goals. When pressed, the panel was mostly optimistic about their future support, stating that external threats to the U.S. have not changed, and research work associated with homeland security and national defense is unlikely to see drastic change. ''We have a strong portfolio in life science and don't expect any changes,'' says Oak Ridge National Laboratory's (ORNL's) Michelle Buchanan. Ongoing federally funded work at the national labs that was started before the Oct. 1st start of the FY2009 fiscal year will continue without any changes - those funds are unaffected by the CR action. This applies as well to any

  3. Fractal model for estimating fracture toughness of carbon nanotube reinforced aluminum oxide

    Rishabh, Abhishek; Joshi, Milind R.; Balani, Kantesh

    2010-01-01

    The current work focuses on predicting the fracture toughness of Al 2 O 3 ceramic matrix composites using a modified Mandelbrot's fractal approach. The first step confirms that the experimental fracture toughness values fluctuate within the fracture toughness range predicted as per the modified fractal approach. Additionally, the secondary reinforcements [such as carbon nanotubes (CNTs)] have shown to enhance the fracture toughness of Al 2 O 3 . Conventional fractural toughness evaluation via fractal approach underestimates the fracture toughness by considering the shortest crack path. Hence, the modified Mandelbrot's fractal approach considers the crack propagation along the CNT semicircumferential surface (three-dimensional crack path propagation) for achieving an improved fracture toughness estimation of Al 2 O 3 -CNT composite. The estimations obtained in the current approach range within 4% error regime of the experimentally measured fracture toughness values of the Al 2 O 3 -CNT composite.

  4. Choice certainty in Discrete Choice Experiments

    Uggeldahl, Kennet Christian; Jacobsen, Catrine; Lundhede, Thomas

    2016-01-01

    In this study, we conduct a Discrete Choice Experiment (DCE) using eye tracking technology to investigate if eye movements during the completion of choice sets reveal information about respondents’ choice certainty. We hypothesise that the number of times that respondents shift their visual...

  5. Tough-coated hard powders for hardmetals of novel properties

    Toth, R.E.; Smid, I.; Kladler, G.; Korb, G.; Sherman, A.; Ettmayer, P.

    2001-01-01

    The properties and performance of conventional materials and composites are constrained by solubility limits, diffusion coefficients, and compatibility of physical and chemical constituent properties in their phase equilibria. To escape these limits, ingenious ways of combining strength, toughness, and wear resistance by way of various coatings and laminations have been devised. These coated tools are systematically discarded after only about 10 % of their wear tolerance has been used. Tough-coated hard powders (TCHP), patented by EnDurAloy (USA), are hard refractory particles CVD coated with nanolayers of WC and Co. Consolidation of TCHP creates an engineered homogeneous cellular structure whose interconnected tough WC-Co 'shells' each contain a wear-resistant core (e.g., TiN). In TCHP's, the coating is throughout the tool, not only on the surface, combining the strength, heat resistance, and toughness of cemented carbides with the chemical and abrasion wear resistance of harder materials. As wear progresses, new wear-resistant material continuously replaces the working surfaces and edges of the tool until its geometry reaches its maximum limits. TCHP tools are then reusable many times. Specific coating and consolidation processes, characterization of compacts, and test comparisons with conventional materials are discussed. (author)

  6. Fracture toughness behavior of irradiated stainless steel in PWR systems

    Xu, H.; Fyfitch, S. [AREVA NP Inc., Lynchburg, Pennsylvania (United States); Tang, H.T. [Electric Power Research Inst., Palo Alto, California (United States)

    2007-07-01

    Data from available research programs were collected and evaluated by the Electric Power Research Institute (EPRI) Materials Reliability Program (MRP) to determine the relationship between fracture toughness and neutron fluence for conditions representative of pressurized water reactor (PWR) conditions. It is shown that the reduction of fracture toughness with increasing neutron dose in both boiling water reactors (BWRs) and PWRs is consistent with that observed in fast reactors. The lower bound fracture toughness observed for irradiated stainless steels in PWRs is 38 MPa{radical}m (34.6 ksi{radical}in) at neutron exposures greater than 6.7 X 10{sup 21} n/cm{sup 2} (E > 1.0 MeV) or approximately 10 dpa. For such levels of fracture toughness, it is recommended that linear-elastic fracture mechanics (LEFM) analyses be considered for design and operational analyses. The results from this study can be used by the nuclear industry to assess the effects of irradiation on stainless steels in PWR systems. (author)

  7. Fracture toughness of ultra high performance concrete by flexural performance

    Manolova Emanuela

    2016-01-01

    Full Text Available This paper describes the fracture toughness of the innovative structural material - Ultra High Performance Concrete (UHPC, evaluated by flexural performance. For determination the material behaviour by static loading are used adapted standard test methods for flexural performance of fiber-reinforced concrete (ASTM C 1609 and ASTM C 1018. Fracture toughness is estimated by various deformation parameters derived from the load-deflection curve, obtained by testing simple supported beam under third-point loading, using servo-controlled testing system. This method is used to be estimated the contribution of the embedded fiber-reinforcement into improvement of the fractural behaviour of UHPC by changing the crack-resistant capacity, fracture toughness and energy absorption capacity with various mechanisms. The position of the first crack has been formulated based on P-δ (load- deflection response and P-ε (load - longitudinal deformation in the tensile zone response, which are used for calculation of the two toughness indices I5 and I10. The combination of steel fibres with different dimensions leads to a composite, having at the same time increased crack resistance, first crack formation, ductility and post-peak residual strength.

  8. On the in vitro fracture toughness of human dentin

    Imbeni, V.; Nalla, R.K.; Bosi, C.; Kinney, J.H.; Ritchie, R.O.

    2002-02-05

    The in vitro fracture toughness of human dention has been reported to be of the order of 3 MPa sqrt m. This result, however is based on a single study for a single orientation, and furthermore involves notched, rather than fatigue precracked, test samples.

  9. Fracture Toughness (KIC) of Lithography Based Manufactured Alumina Ceramic

    Nindhia, T. G. T.; Schlacher, J.; Lube, T.

    2018-04-01

    Precision shaped ceramic components can be obtained by an emerging technique called Lithography based Ceramic Manufacturing (LCM). A green part is made from a slurry consisting of a ceramic powder in a photocurable binder with addition of dispersant and plasticizer. Components are built in a layer–by-layer way by exposing the desired cross- sections to light. The parts are subsequently sintered to their final density. It is a challenge to produce ceramic component with this method that yield the same mechanical properties in all direction. The fracture toughness (KIc) of of LCM-alumina (prepared at LITHOZ GmbH, Austria) was tested by using the Single-Edge-V-Notched Beam (SEVNB) method. Notches are made into prismatic bend-bars in all three direction X, Y and Z to recognize the value of fracture toughness of the material in all three directions. The microstructure was revealed with optical microscopy as well as Scanning Electron Microscopy (SEM). The results indicate that the fracture toughness in Y-direction has the highest value (3.10 MPam1/2) that is followed by the one in X-direction which is just a bit lower (2.90 MPam1/2). The Z-direction is found to have a similar fracture toughness (2.95 MPam1/2). This is supported by a homogeneous microstructure showing no hint of the layers used during production.

  10. Prediction of fracture toughness temperature dependence applying neural network

    Dlouhý, Ivo; Hadraba, Hynek; Chlup, Zdeněk; Šmída, T.

    2011-01-01

    Roč. 11, č. 1 (2011), s. 9-14 ISSN 1451-3749 R&D Projects: GA ČR(CZ) GAP108/10/0466 Institutional research plan: CEZ:AV0Z20410507 Keywords : brittle to ductile transition * fracture toughness * artificial neural network * steels Subject RIV: JL - Materials Fatigue, Friction Mechanics

  11. Sharing Ideas: Tough Times Encourage Colleges to Collaborate

    Fain, Paul; Blumenstyk, Goldie; Sander, Libby

    2009-01-01

    Tough times are encouraging colleges to share resources in a variety of areas, including campus security, research, and degree programs. Despite its veneer of cooperation, higher education is a competitive industry, where resource sharing is eyed warily. But the recession is chipping away at that reluctance, and institutions are pursuing…

  12. A graphical interface to the TOUGH family of flow simulators

    O`Sullivan, M.J.; Bullivant, D.P. [Univ. of Auckland (New Zealand)

    1995-03-01

    A graphical interface for the TOUGH family of simulators is presented. The interface allows the user to graphically create or modify a computer model and then to graphically examine the simulation results. The package uses the X Window System, enabling it to be used on many computer platforms.

  13. Mexico's critical choices

    Marcos, E.

    1990-01-01

    In Mexico, the 1982 fall in international oil prices shook the national conscience and pushed the Mexican people in search of a new national image and toward the choices they must make to attain that image. But, according to the author of this paper, the country as a whole has already made critical choices for overall strategy and there are reasons for optimism. In the current economic environment of growing domestic demand and enhanced international competitiveness, the author sees PEMEX (the Mexican national oil company) facing not only the challenge of responding to the rapid changes taking place in the Mexican economy, but also making a significant contribution toward the solid and stable growth of the country. The relevant question is how PEMEX will live up to these expectations. This paper describes several steps PEMEX has taken already or is preparing to take in order to meet this challenge, including: investment in the domestic petrochemical industry; entry into the Eurobond market; development of new methods of project financing

  14. MENTAL TOUGHNESS: A COMPARATIVE STUDY ON KFUPM UNIVERSITY TEAMS

    MOHAMMED HAMDAN

    2012-06-01

    Full Text Available AbstractMental toughness is an attribute that is often associated with successful performance in competitions. Mental toughness and its importance in competitive Sports have been documented in literature (A.S. Goldberg, 1998; K. Hodge, 1994; J. Tunney, 1987; R.M. Williams, 1988. In sports, many things are left to chance as, sports are predictably unpredictable. Sports persons who enter the competitive arena soon realize that there is more to competition than simply learning the physical skills. It is one thing to possess the physical and mental skills and yet another to be able to use them when needed. Every athletic contest is a contest of control of the delicate mind-body connection, which is dramatically clear within the competitive arena (J.E. Loehr, 1982.Purpose: 1. To compare the mental toughness between King Fahd University of Petroleum and Minerals (KFUPM Judo and Karate teams; 2. To compare the mental toughness between KFUPM Swimming and Track & Field teams. Methods A total of 26 players who are part of KFUPM Judo, Karate , Swimming and Track & Field University teams (2011-12 with age ranging from 18-20 years were selected as subjects for study and were divided into four groups namely; Judo (N= 6, Karate (N= 5, Swimming (N= 8 and Track & Field (N= 7. Mental toughness questionnaire of Tiwari and Sharma (2006 was administered to the subjects. The questionnaire consists of 48 statements and has six sub- scales namely: Self Confidence, Attention Control, Motivation, Goal Setting, Visual Imagery and Attitude Control. T- Test was applied to compare means between the groups. Statistical significance was set at 0.05 levels. Results T- Test failed to reveal significant difference on mental toughness (MT between KFUPM Judo and Karate teams (p = .7 > .05. T-Test also failed to reveal significant difference on MT between KFUPM Swimming and Track & Field teams (p = .122 > .05. T-Test revealed significant difference on Self Confidence between KFUPM

  15. Effectiveness and Cost-Effectiveness of Occupation-Based Occupational Therapy Using the Aid for Decision Making in Occupation Choice (ADOC) for Older Residents: Pilot Cluster Randomized Controlled Trial

    Nagayama, Hirofumi; Tomori, Kounosuke; Ohno, Kanta; Takahashi, Kayoko; Ogahara, Kakuya; Sawada, Tatsunori; Uezu, Sei; Nagatani, Ryutaro; Yamauchi, Keita

    2016-01-01

    Background Care-home residents are mostly inactive, have little interaction with staff, and are dependent on staff to engage in daily occupations. We recently developed an iPad application called the Aid for Decision-making in Occupation Choice (ADOC) to promote shared decision-making in activities and occupation-based goal setting by choosing from illustrations describing daily activities. This study aimed to evaluate if interventions based on occupation-based goal setting using the ADOC could focus on meaningful activities to improve quality of life and independent activities of daily living, with greater cost-effectiveness than an impairment-based approach as well as to evaluate the feasibility of conducting a large cluster, randomized controlled trial. Method In this single (assessor)-blind pilot cluster randomized controlled trial, the intervention group (ADOC group) received occupational therapy based on occupation-based goal setting using the ADOC, and the interventions were focused on meaningful occupations. The control group underwent an impairment-based approach focused on restoring capacities, without goal setting tools. In both groups, the 20-minute individualized intervention sessions were conducted twice a week for 4 months. Main Outcome Measures Short Form-36 (SF-36) score, SF-6D utility score, quality adjusted life years (QALY), Barthel Index, and total care cost. Results We randomized and analyzed 12 facilities (44 participants, 18.5% drop-out rate), with 6 facilities each allocated to the ADOC (n = 23) and control (n = 21) groups. After the 4-month intervention, the ADOC group had a significantly greater change in the BI score, with improved scores (P = 0.027, 95% CI 0.41 to 6.87, intracluster correlation coefficient = 0.14). No other outcome was significantly different. The incremental cost-effectiveness ratio, calculated using the change in BI score, was $63.1. Conclusion The results suggest that occupational therapy using the ADOC for older

  16. Friction weld ductility and toughness as influenced by inclusion morphology

    Eberhard, B.J.; Schaaf, B.W. Jr.; Wilson, A.D.

    1983-01-01

    Friction welding consistently provides high strength, freedom from fusion defects, and high productivity. However, friction welds in carbon steel exhibit impact toughness and bend ductility that are significantly lower than that of the base metal. The inclusion content and morphology were suspected to be major contributors to the reduction in weld ductility. For this reason, four electric furnace steels - three types of ASTM A516 Grade 70, and an ASTM A737 Grade B steel - were investigated. Friction welds were made by both the inertia and direct drive process variations and the welds evaluated. It was shown that friction welds of inclusion-controlled steels exhibited much improved toughness and bend ductility were demonstrated. Upper shelf impact energy was equivalent to or greater than that of the base metal in the short transverse direction. The transition temperature range for all four materials was shifted to higher temperatures for both types of friction welds. Under the conditions of this test, the direct drive friction welds showed a greater shift than the inertia friction welds. The ductility and toughness of welds in A737 Grade B steel were superior to welds in A516 Grade 70 steels, reflecting the superior properties of the base metal. Welds of the A737 material had usable Charpy V-notch impact toughness of 20 to 30 ft-lb (27 to 41 J) at temperatures as low as -40 0 F (-40 0 C). All the welds had an acicular structure. The differences in properties between the inertia and direct drive friction welds appear associated with microstructural variations. These variations resulted from the different heat inputs and cooling rates of the two process variations were demonstrated. The beneficial effects of inclusion control on toughness and ductility. In addition, it also indicates that additional improvements may be attainable through control of the as-welded microstructure by process manipulation

  17. Pairwise Choice Markov Chains

    Ragain, Stephen; Ugander, Johan

    2016-01-01

    As datasets capturing human choices grow in richness and scale---particularly in online domains---there is an increasing need for choice models that escape traditional choice-theoretic axioms such as regularity, stochastic transitivity, and Luce's choice axiom. In this work we introduce the Pairwise Choice Markov Chain (PCMC) model of discrete choice, an inferentially tractable model that does not assume any of the above axioms while still satisfying the foundational axiom of uniform expansio...

  18. The Determinants of Food Choice

    Leng, Gareth; Adan, Roger A. H.; Belot, Michele

    2017-01-01

    , we need to be able to make valid predictions about the consequences of proposed interventions, and for this, we need a better understanding of the determinants of food choice. These determinants include dietary components (e.g. highly palatable foods and alcohol), but also diverse cultural and social...

  19. Social media and consumer choice

    Bronner, F.; de Hoog, R.

    2014-01-01

    Social media are becoming increasingly important for consumer decisions. This holds true in particular for vacation decision-making, as an example of a high-involvement decision. The research focuses upon the relation between the information people search regarding aspects or properties of choice

  20. Behavioural social choice: a status report.

    Regenwetter, Michel; Grofman, Bernard; Popova, Anna; Messner, William; Davis-Stober, Clintin P; Cavagnaro, Daniel R

    2009-03-27

    Behavioural social choice has been proposed as a social choice parallel to seminal developments in other decision sciences, such as behavioural decision theory, behavioural economics, behavioural finance and behavioural game theory. Behavioural paradigms compare how rational actors should make certain types of decisions with how real decision makers behave empirically. We highlight that important theoretical predictions in social choice theory change dramatically under even minute violations of standard assumptions. Empirical data violate those critical assumptions. We argue that the nature of preference distributions in electorates is ultimately an empirical question, which social choice theory has often neglected. We also emphasize important insights for research on decision making by individuals. When researchers aggregate individual choice behaviour in laboratory experiments to report summary statistics, they are implicitly applying social choice rules. Thus, they should be aware of the potential for aggregation paradoxes. We hypothesize that such problems may substantially mar the conclusions of a number of (sometimes seminal) papers in behavioural decision research.

  1. Comparisons of irradiation-induced shifts in fracture toughness, crack arrest toughness, and Charpy impact energy in high-copper welds

    Corwin, W.R.; Nanstad, R.K.; Iskander, S.K.

    1991-01-01

    The Heavy-Section Steel Irradiation (HSSI) Program is examining relative shifts and changes in shape of fracture and crack-arrest toughness versus temperature behavior for two high-copper welds. Fracture toughness 100-MPa√m temperature shifts are greater than Charpy 41-J shifts for both welds. Mean curve fits to the fracture toughness data provide mixed results regarding curve shape changes, but curves constructed as lower boundaries indicate lower slopes. Preliminary crack-arrest toughness results indicate that shifts of lower-bound curves are approximately the same as CVN 41-J shifts with no shape changes

  2. Relationship between mental toughness, stress appraisal, and innovation performance of R&D personnel

    Feng Jin

    2016-01-01

    Full Text Available Four hundred and two R&D personnel were surveyed through questionnaires to study the relationship between mental toughness, stress appraisal (including experience of stress and stress control, and innovation performance. The findings reveal a significant negative correlation between mental toughness and stress experience and a significant positive correlation between mental toughness and both stress control and innovation performance. Furthermore, although the experience of stress was negatively correlated with innovation performance, stress control had the opposite effect. Experience of stress and stress control were the mediating variables for mental toughness and innovation performance, respectively. There was also a significant interaction effect between stress appraisal and mental toughness.

  3. Latent variables and route choice behavior

    Prato, Carlo Giacomo; Bekhor, Shlomo; Pronello, Cristina

    2012-01-01

    In the last decade, a broad array of disciplines has shown a general interest in enhancing discrete choice models by considering the incorporation of psychological factors affecting decision making. This paper provides insight into the comprehension of the determinants of route choice behavior...... and bound algorithm. A hybrid model consists of measurement equations, which relate latent variables to measurement indicators and utilities to choice indicators, and structural equations, which link travelers’ observable characteristics to latent variables and explanatory variables to utilities. Estimation...

  4. Testicular Rupture: A Tough Nut to Crack

    Tyler L. Holliday

    2017-07-01

    Full Text Available Blunt scrotal injury represents a diagnostic dilemma for emergency physicians (EP. Consequently, point-of-care ultrasound (POCUS has emerged as a tool for early investigation of the acute scrotum in the emergency department. We describe a case where an EP used scrotal POCUS to immediately visualize the loss of testicular contour and underlying heterogeneous parenchyma to rapidly make the diagnosis of testicular rupture in a young male presenting with scrotal trauma. The use of POCUS in this case expedited therapy, likely improving the patient’s outcome. To our knowledge, this is the first detailed description of testicular rupture diagnosed with POCUS by an EP

  5. To investigate the effect of heat treatment on fracture toughness of welded joints

    Hameed, A.; Pasha, R.A.; Shah, M.

    2013-01-01

    Annealing as a post weld heat treatment (PWHT), increases toughness in the welding joints of medium carbon steel in the same way as it increases toughness of the non-welded medium carbon steel. Measurement of increase in toughness through PWHT is focus of the present research work. Welded samples of commercially available steel AISI -1035 have been used for the proposed evaluation. The samples welded by two different techniques namely oxyacetylene gas welding and manual metal arc welding, passed through annealing process along with non-welded samples for comparison of increase in toughness. Toughness measured by impact tests revealed the improvement, which in the order of increasing effects is in gas welded, electric welded and non-welded samples. The aim of the present research was to measure the improvement in fracture toughness through post weld heat treatment (annealing). It has been shown that toughness increases as the structural flaws decrease. (author)

  6. Factors Influencing Food Choice in the Elderly Mauritian Population

    admpather

    food choice in order to help people make healthful food and beverage choices .... consumption patterns, lifestyles, health status and the different factors .... relative importance in human eating behaviour: review and preliminary suggestions for.

  7. Two Philosophical Errors Concerning School Choice.

    Brighouse, Harry

    1997-01-01

    Argues, in contrast to David Hargreaves, that libertarianism implies a mild presumption against school choice, and that notions of common good are significant to educational decision making only when deciding between sets of institutions that perform equally well at delivering their obligations. Links these issues to questions about school choice.…

  8. Choice Complexity, Benchmarks and Costly Information

    Harms, Job; Rosenkranz, S.; Sanders, M.W.J.L.

    In this study we investigate how two types of information interventions, providing a benchmark and providing costly information on option ranking, can improve decision-making in complex choices. In our experiment subjects made a series of incentivized choices between four hypothetical financial

  9. Emotion and decision making.

    Lerner, Jennifer S; Li, Ye; Valdesolo, Piercarlo; Kassam, Karim S

    2015-01-03

    A revolution in the science of emotion has emerged in recent decades, with the potential to create a paradigm shift in decision theories. The research reveals that emotions constitute potent, pervasive, predictable, sometimes harmful and sometimes beneficial drivers of decision making. Across different domains, important regularities appear in the mechanisms through which emotions influence judgments and choices. We organize and analyze what has been learned from the past 35 years of work on emotion and decision making. In so doing, we propose the emotion-imbued choice model, which accounts for inputs from traditional rational choice theory and from newer emotion research, synthesizing scientific models.

  10. A Subjective Rational Choice

    Vinogradov, G. P.

    2017-01-01

    The problem of constructing a choice model of an agent with endogenous purposes of evolution is under debate. It is demonstrated that its solution requires the development of well-known methods of decision-making while taking into account the relation of action mode motivation to an agent’s ambition to implement subjectively understood interests and the environment state. The latter is submitted for consideration as a purposeful state situation model that exists only in the mind of an agent. It is the situation that is a basis for getting an insight into the agent’s ideas on the possible selected action mode results. The agent’s ambition to build his confidence in the feasibility of the action mode and the possibility of achieving the desired state requires him to use the procedures of forming an idea model based on the measured values of environment state. This leads to the gaming approach for the choice problem and its solution can be obtained on a set of trade-off alternatives.

  11. Enhancing School Wellness Environments to Make to Make the Healthy Choice the Easy Choice

    Stevens, JA; Alie, K

    2016-01-01

    The Virginia Department of Health’s Division of Prevention & Health Promotion has partnered with Virginia Cooperative Extension’s Family Nutrition Program and Virginia Tech in order to enhance Extension’s efforts to promote and support student health in select K-12 schools by implementing a variety of evidence-based nutrition and physical activity platforms intended to enhance school wellness environments, policies, and practices. Additionally, the implementation of a consistent statewide hea...

  12. Tough graphene-polymer microcellular foams for electromagnetic interference shielding.

    Zhang, Hao-Bin; Yan, Qing; Zheng, Wen-Ge; He, Zhixian; Yu, Zhong-Zhen

    2011-03-01

    Functional polymethylmethacrylate (PMMA)/graphene nanocomposite microcellular foams were prepared by blending of PMMA with graphene sheets followed by foaming with subcritical CO(2) as an environmentally benign foaming agent. The addition of graphene sheets endows the insulating PMMA foams with high electrical conductivity and improved electromagnetic interference (EMI) shielding efficiency with microwave absorption as the dominant EMI shielding mechanism. Interestingly, because of the presence of the numerous microcellular cells, the graphene-PMMA foam exhibits greatly improved ductility and tensile toughness compared to its bulk counterpart. This work provides a promising methodology to fabricate tough and lightweight graphene-PMMA nanocomposite microcellular foams with superior electrical and EMI shielding properties by simultaneously combining the functionality and reinforcement of the graphene sheets and the toughening effect of the microcellular cells.

  13. Flexural Toughness of Ring-Shaped Waste Bottle Fiber Concrete

    Faisal S. K.

    2016-01-01

    Full Text Available Polyethylene terephthalate (PET bottles are plastic containers that are typically discarded, and thus, cause environmental pollution. To solve this problem, PET bottles are recycled incorporating with concrete. A ring-shaped PET (RPET fiber are introduced in this study and designed with a special shape to mobilize fiber yielding rather than fiber pullout. Therefore, aim of this paper is to investigate the influence of RPET bottles fibre in terms of toughness strength. The width of RPET fibers is fixed at 5 and 10 mm and the loads were applied to the third points of the specimen. The experiment indicates that RPET-5 and RPET-10 FC presented an increase in the toughness index of I20 on averages of 23.1% and 39.9% respectively, compared to normal specimens. It can conclude that incorporating RPET fiber in concrete presents significant improved of concrete properties.

  14. Renewable Pentablock Copolymers Containing Bulky Natural Rosin for Tough Bioplastics

    Rahman, Md Anisur; Ganewatta, Mitra S.; Lokupitiya, Hasala N.; Liang, Yuan; Stefik, Morgan; Tang, Chuanbing

    Renewable polymers have received significant attention due to environmental concerns on petrochemical counterparts. One of the most abundant natural biomass is resin acids. However, most polymers derived from resin acids are low molecular weight and brittle because of the high chain entanglement molecular weight resulted from the bulky hydrophenanthrene pendant group. It is well established that the brittleness can be overcome by synthesizing multi-block copolymers with low entanglement molecular weight components. We investigated the effects of chain architecture and microdomain orientation on mechanical properties of both tri and pentablock copolymers. We synthesized rosin-containing A-B-A-B-A type pentablock and A-B-A type triblock copolymers to improve their mechanical properties. Pentablock copolymers showed higher strength and better toughness as compared to triblock copolymers, both superior to homopolymers. The greater toughness of pentablock copolymers is due to the presence of the rosin based midblock chains that act as bridging chains between two polynorbornene blocks.

  15. Mental Toughness in Competitive Tennis: Relationships with Resilience and Stress

    Richard Gregory Cowden

    2016-03-01

    Full Text Available The present study investigated the relationships between mental toughness (MT, resilience, and stress among competitive South African tennis players. A total of 351 tennis players participating at various competitive standards completed the Sport Mental Toughness Questionnaire, the Resilience Scale for Adults, and a modified version of the Recovery-Stress Questionnaire for Athletes. The results indicated that total MT was positively associated with total resilience (r = .59, but negatively associated with total stress (r = -.44. The resilience subscales of perception of self, perception of future, social competence, and social resources, but not family cohesion, significantly predicted total MT (R2 = .35. Both total resilience and total MT significantly predicted total stress (R2 = .21. Based on the findings, interrelations between MT and resilience are explored, implications outlined, and additional research is suggested to ascertain the contextual relevance and outcomes associated with each construct in sport.

  16. Mental Toughness in Competitive Tennis: Relationships with Resilience and Stress.

    Cowden, Richard G; Meyer-Weitz, Anna; Oppong Asante, Kwaku

    2016-01-01

    The present study investigated the relationships between mental toughness (MT), resilience, and stress among competitive South African tennis players. A total of 351 tennis players participating at various competitive standards completed the Sports Mental Toughness Questionnaire, the Resilience Scale for Adults, and a modified version of the Recovery-Stress Questionnaire for Athletes. The results indicated that total MT was positively associated with total resilience (r = 0.59), but negatively associated with total stress (r = -0.44). The resilience subscales of perception of self, perception of future, social competence, and social resources, but not family cohesion, significantly predicted total MT (R (2) = 0.35). Both total resilience and total MT significantly predicted total stress (R (2) = 0.21). Based on the findings, interrelations between MT and resilience are explored, implications outlined, and additional research is suggested to ascertain the contextual relevance and outcomes associated with each construct in sport.

  17. A portable fracture toughness tester for biological materials

    Darvell, B. W.; Lee, P. K. D.; Yuen, T. D. B.; Lucas, P. W.

    1996-06-01

    A portable mechanical tester is described which is both lightweight and cheap to produce. The machine is simple and convenient to operate and requires only a minimum of personnel training. It can be used to measure the fundamental mechanical properties of pliant solids, particularly toughness (in the sense of `work of fracture') using either scissors or wedge tests. This is achieved through a novel hardware integration technique. The circuits are described. The use of the machine does not require a chart recorder but it can be linked to a personal computer, either to show force - displacement relationships or for data storage. The design allows the use of any relatively `soft' mechanical test, i.e. tests in which the deformability of the frame of the machine and its load cell do not introduce significant errors into the results. Examples of its use in measuring the toughness of biomaterials by scissors (paper, wood) and wedges (mung bean starch gels) are given.

  18. Allowable minimum upper shelf toughness for nuclear reactor pressure vessels

    Zahoor, A.

    1988-05-01

    The paper develops methodology and procedure for determining the allowable minimum upper shelf toughness for continued safe operation of nuclear reactor pressure vessels. Elastic-plastic fracture mechanics analysis method based on the J-integral tearing modulus (J/T) approach is used. Closed from expressions for the applied J and tearing modulus are presented for finite length, part-throughwall axial flaw with aspect ratio of 1/6. Solutions are then presented for Section III, Appendix G flaw. A simple flaw evaluation procedure that can be applied quickly by utility engineers is presented. An attractive feature of the simple procedure is that tearing modulus calculations are not required by the user, and a solution for the slope of the applied J/T line is provided. Results for the allowable minimum upper shelf toughness are presented for a range of reactor pressure vessel thickness and heatup/cooldown rates.

  19. Allowable minimum upper shelf toughness for nuclear reactor pressure vessels

    Zahoor, A.

    1988-01-01

    The paper develops methodology and procedure for determining the allowable minimum upper shelf toughness for continued safe operation of nuclear reactor pressure vessels. Elastic-plastic fracture mechanics analysis method based on the J-integral tearing modulus (J/T) approach is used. Closed from expressions for the applied J and tearing modulus are presented for finite length, part-throughwall axial flaw with aspect ratio of 1/6. Solutions are then presented for Section III, Appendix G flaw. A simple flaw evaluation procedure that can be applied quickly by utility engineers is presented. An attractive feature of the simple procedure is that tearing modulus calculations are not required by the user, and a solution for the slope of the applied J/T line is provided. Results for the allowable minimum upper shelf toughness are presented for a range of reactor pressure vessel thickness and heatup/cooldown rates. (orig.)

  20. Size Effect in Fracture Toughness Determination of Brittle Matreials

    Chlup, Zdeněk; Dlouhý, Ivo

    2006-01-01

    Roč. 45, - (2006), s. 101-106 ISSN 1662-0356. [CIMTEC 2006. Intrenational Ceramics Congress /11./. Acireale, 04.06.2006-09.06.2006] R&D Projects: GA MŠk ME 854; GA ČR GP106/05/P119 Institutional research plan: CEZ:AV0Z20410507 Keywords : fracture toughness * ceramics * straight-notch technique Subject RIV: JL - Materials Fatigue, Friction Mechanics

  1. Mental Health staff views on improving burnout and mental toughness

    Posner, Zoe; Janssen, Jessica; Roddam, Hazel

    2017-01-01

    Purpose- Burnout in mental health staff is acknowledged as a major problem. The purpose of this paper is to gain an understanding of mental health staff views on improving burnout and mental toughness in mental health staff.\\ud Design/methodology/approach-Ten participants from two mental health rehabilitation units across the North West of England took part in a Nominal Group Technique (NGT). Participants consisted of mental health workers from varied roles in order to\\ud capture views from a...

  2. Fracture toughness evaluation of circumferentially-cracked round bars

    Scibetta, M.

    1996-05-01

    The measure of the fracture toughness of a circumferentially-cracked round bar is generally performed through approximate formulae. Comparison of existing formulae to finite element results does not always show good agreement. Therefore an eta factor is introduced in order to improve the existing analytical formula. The axisymmetrical geometry is generally considered to be a high constrained geometry. Finite element calculations are performed to verify and quantify the constraint relative to the three point bending configuration (precracked Charpy)

  3. Thin slab processing of acicular ferrite steels with high toughness

    Reip, Carl-Peter; Hennig, Wolfgang; Hagmann, Rolf [SMS Demag Aktiengesellschaft, Duesseldorf (Germany); Sabrudin, Bin Mohamad Suren; Susanta, Ghosh; Lee, Weng Lan [Megasteel Sdn Bhd, Banting (Malaysia)

    2005-07-01

    Near-net-shape casting processes today represent an important option in steelmaking. High productivity and low production cost as well as the variety of steel grades that can be produced plus an excellent product quality are key factors for the acceptance of such processes in markets all over the world. Today's research focuses on the production of pipe steel with special requirements in terms of toughness at low temperatures. The subject article describes the production of hot strip made from acicular ferritic / bainitic steel grades using the CSP thin-slab technology. In addition, the resulting strength and toughness levels as a function of the alloying concepts are discussed. Optimal control of the CSP process allows the production of higher-strength hot-rolled steel grades with a fine-grain acicular-ferritic/bainitic microstructure. Hot strip produced in this way is characterized by a high toughness at low temperatures. In a drop weight tear test, transition temperatures of up to -50 deg C can be achieved with a shear-fracture share of 85%. (author)

  4. Rapid estimation of fatigue entropy and toughness in metals

    Liakat, M.; Khonsari, M.M., E-mail: khonsari@me.lsu.edu

    2014-10-15

    Highlights: • A correlation is developed to predict fatigue entropy and toughness of metals. • Predictions are made based on the thermal response of the materials. • The trend of hysteresis energy and temperature evolutions is discussed. • Predicted results are found to be in good agreement to those measured. - Abstract: An analytical model and an experimental procedure are presented for estimating the rate and accumulation of thermodynamic entropy and fatigue toughness in metals subjected to cyclic uniaxial tension–compression tests. Entropy and plastic strain energy generations are predicted based on the thermal response of a specimen at different levels of material damage. Fatigue tests are performed with cylindrical dogbone specimens made of tubular low-carbon steel 1018 and solid medium-carbon steel 1045, API 5L X52, and Al 6061. The evolution of the plastic strain energy generation, temperature, and thermal response throughout a fatigue process are presented and discussed. Predicted entropy accumulation and fatigue toughness obtained from the proposed method are found to be in good agreement to those obtained using a load cell and an extensometer over the range of experimental and environmental conditions considered.

  5. Rapid estimation of fatigue entropy and toughness in metals

    Liakat, M.; Khonsari, M.M.

    2014-01-01

    Highlights: • A correlation is developed to predict fatigue entropy and toughness of metals. • Predictions are made based on the thermal response of the materials. • The trend of hysteresis energy and temperature evolutions is discussed. • Predicted results are found to be in good agreement to those measured. - Abstract: An analytical model and an experimental procedure are presented for estimating the rate and accumulation of thermodynamic entropy and fatigue toughness in metals subjected to cyclic uniaxial tension–compression tests. Entropy and plastic strain energy generations are predicted based on the thermal response of a specimen at different levels of material damage. Fatigue tests are performed with cylindrical dogbone specimens made of tubular low-carbon steel 1018 and solid medium-carbon steel 1045, API 5L X52, and Al 6061. The evolution of the plastic strain energy generation, temperature, and thermal response throughout a fatigue process are presented and discussed. Predicted entropy accumulation and fatigue toughness obtained from the proposed method are found to be in good agreement to those obtained using a load cell and an extensometer over the range of experimental and environmental conditions considered

  6. Influence of texture on fracture toughness of zircaloy cladding

    Grigoriev, V. [Studsvik Material AB, Nykoeping (Sweden); Andersson, Stefan [Royal Inst. of Tech., Stockholm (Sweden)

    1997-06-01

    The correlation between texture and fracture toughness of Zircaloy 2 cladding has been investigated in connection with axial cracks in fuel rods. The texture of the cladding determines the anisotropy of plasticity of the cladding which, in turn, should influence the strain conditions at the crack-tip. Plastic strains in the cladding under uniaxial tension were characterised by means of the anisotropy constants F, G and H calculated according to Hill`s theory. Test temperatures between 20 and 300 deg C do not influence the F, G and H values. Any significant effect of hydrogen (about 500 wtppm) on the anisotropy constants F, G and H has not been revealed at a test temperature of 300 deg C. The results, obtained for stress-relieved and recrystallized cladding with different texture, show an obvious influence of texture on the fracture toughness of Zircaloy cladding. A higher fracture toughness has been found for cladding with more radial texture. With a 2 page summary in Swedish. 32 refs, 18 figs.

  7. Crack arrest toughness of structural steels evaluated by compact test

    Nakano, Yoshifumi; Tanaka, Michihiro

    1982-01-01

    Crack arrest tests such as compact, ESSO and DCB tests were made on SA533B Cl. 1, HT80 and KD32 steels to evaluate the crack arrest toughness. The main results obtained are as follows: (1) The crack arrest toughness could be evaluated by K sub(Ia) which was obtained by the static analysis of compact test. (2) K sub(ID) determined by the dynamic analysis of compact test was greater than K sub(Ia), though K sub(ID) became close to K sub(Ia)/K sub(Q) became a unity where K sub(Q) is the stress intensity factor at the crack initiation. (3) No significant difference was observed between K sub(Ia) and K sub(ca) obtained by ESSO and DCB tests, though K sub(ca) obtained by DCB test tended to be smaller than K sub(Ia) at lower temperatures. (4) K sub(Ia) was smaller than K sub(Ic) in the transition temperature range, while it was greater than K sub(Id). In the temperature range where K sub(Ic), which was determined from J sub(Ic), decreased with temperature increase, however, it was smaller than K sub(Ia). (5) The fracture appearance transition temperature and the absorbed energy obtained by 2 mm V-notch Charpy test were appropriate parameters for representing the crack arrest toughness, while the NDT temperature was not. (author)

  8. Performance and biocompatibility of extremely tough alginate/polyacrylamide hydrogels.

    Darnell, Max C; Sun, Jeong-Yun; Mehta, Manav; Johnson, Christopher; Arany, Praveen R; Suo, Zhigang; Mooney, David J

    2013-11-01

    Although hydrogels now see widespread use in a host of applications, low fracture toughness and brittleness have limited their more broad use. As a recently described interpenetrating network (IPN) of alginate and polyacrylamide demonstrated a fracture toughness of ≈ 9000 J/m(2), we sought to explore the biocompatibility and maintenance of mechanical properties of these hydrogels in cell culture and in vivo conditions. These hydrogels can sustain a compressive strain of over 90% with minimal loss of Young's Modulus as well as minimal swelling for up to 50 days of soaking in culture conditions. Mouse mesenchymal stem cells exposed to the IPN gel-conditioned media maintain high viability, and although cells exposed to conditioned media demonstrate slight reductions in proliferation and metabolic activity (WST assay), these effects are abrogated in a dose-dependent manner. Implantation of these IPN hydrogels into subcutaneous tissue of rats for 8 weeks led to mild fibrotic encapsulation and minimal inflammatory response. These results suggest the further exploration of extremely tough alginate/PAAM IPN hydrogels as biomaterials. © 2013 Elsevier Ltd. All rights reserved.

  9. Stainless steel submerged arc weld fusion line toughness

    Rosenfield, A.R.; Held, P.R.; Wilkowski, G.M.

    1995-04-01

    This effort evaluated the fracture toughness of austenitic steel submerged-arc weld (SAW) fusion lines. The incentive was to explain why cracks grow into the fusion line in many pipe tests conducted with cracks initially centered in SAWS. The concern was that the fusion line may have a lower toughness than the SAW. It was found that the fusion line, Ji. was greater than the SAW toughness but much less than the base metal. Of greater importance may be that the crack growth resistance (JD-R) of the fusion line appeared to reach a steady-state value, while the SAW had a continually increasing JD-R curve. This explains why the cracks eventually turn to the fusion line in the pipe experiments. A method of incorporating these results would be to use the weld metal J-R curve up to the fusion-line steady-state J value. These results may be more important to LBB analyses than the ASME flaw evaluation procedures, since there is more crack growth with through-wall cracks in LBB analyses than for surface cracks in pipe flaw evaluations

  10. Evaluation of WWER-1000 vessel materials fracture toughness

    Grinik, Eh.U.; Revka, V.N.; Chirko, L.I.; Chajkovskij, Yu.V.

    2007-01-01

    The lifetime of WWER-1000-type reactor vessels is finally conditioned by the fracture toughness (crack growth resistance) of RPV materials. Up to now in line with the regulations the fracture toughness is characterized by the critical temperature of brittleness determined by the results of the Charpy specimen impact testing. Such approach is typical for all countries operating the water pressure reactors. However, regulatory approach is known from the western specialists not always to characterize adequately the crack growth resistance of the vessel materials and in some cases to underestimate their characteristics in the reference state that leads to unreasonably high conservatism. Excessive conservatism may lead to the invalid restrictions in the operating modes and the service life of the reactor vessel. Therefore there appeared the necessity to apply another approaches based on the state-of-the-art experimental methods of the fracture mechanics and allowing evaluating the fracture toughness parameters sufficiently. The paper presents the results of the comparison of the regulatory approach and the Master curve approach from the point of view of the adequate determination of the vessel material crack growth resistance parameters. Analysis of the experimental data of the surveillance specimens illustrated the potential possibility of applying the new statistical method for the WWER-1000- type reactor vessel lifetime extension

  11. Characterization of fracture toughness of epoxy resin after hygrothermal aging

    Quispe, Gustavo Q.

    2013-07-01

    Characterization of fracture toughness of epoxy resin after hygrothermal ageing Gustavo Quino Quispe The aim of this work is to characterize the e ects of hygrothermal aging in the plain strain fracture toughness of the epoxy system composed by cycloaliphatic epoxy resin and diglycidyl ether of bisphenol-A (DGEBA). For this, after having been under hygrothermal aging in a climatic chamber, epoxy samples were studied using ASTM D5045 fracture toughness test, and micrography and roughness measurements of the fracture surface. It is reported a rapid decrease of GIc and KIc during the rst 2 days. Moreover, a numerical model [13] was used to simulate and see with more detail the water absorption in the aged samples. From that, it was observed the heterogeneous distribution of water. Accordingly, it was proposed that the results should be correlated with the water content at the vicinity of the crack tip. Consequently, it was possible to obtain, by quasi-static simulations, the ideal load-displacement curves of crack propagation in the heterogeneous samples. Finally, another contribution of this work is the study of the fracture surface, that gives a clue of the relationship among the fracture energy, the appearance of microcracks in the fracture surface, and the roughness (Ra).

  12. Anisotropic toughness and strength in graphene and its atomistic origin

    Hossain, M. Zubaer; Ahmed, Tousif; Silverman, Benjamin; Khawaja, M. Shehroz; Calderon, Justice; Rutten, Andrew; Tse, Stanley

    2018-01-01

    This paper presents the implication of crystallographic orientation on toughness and ideal strength in graphene under lattice symmetry-preserving and symmetry-breaking deformations. In symmetry-preserving deformation, both toughness and strength are isotropic, regardless of the chirality of the lattice; whereas, in symmetry-breaking deformation they are strongly anisotropic, even in the presence of vacancy defects. The maximum and minimum of toughness or strength occur for loading along the zigzag direction and the armchair direction, respectively. The anisotropic behavior is governed by a complex interplay among bond-stretching deformation, bond-bending deformation, and the chirality of the lattice. Nevertheless, the condition for crack-nucleation is dictated by the maximum bond-force required for bond rupture, and it is independent of the chiral angle of the lattice or loading direction. At the onset of crack-nucleation a localized nucleation zone is formed, wherein the bonds rupture locally satisfying the maximum bond-force criterion. The nucleation zone acts as the physical origin in triggering the fracture nucleation process, but its presence is undetectable from the macroscopic stress-strain data.

  13. Don't make me angry, you wouldn't like me when I'm angry: Volitional choices to act or inhibit are modulated by subliminal perception of emotional faces.

    Parkinson, Jim; Garfinkel, Sarah; Critchley, Hugo; Dienes, Zoltan; Seth, Anil K

    2017-04-01

    Volitional action and self-control-feelings of acting according to one's own intentions and in being control of one's own actions-are fundamental aspects of human conscious experience. However, it is unknown whether high-level cognitive control mechanisms are affected by socially salient but nonconscious emotional cues. In this study, we manipulated free choice decisions to act or withhold an action by subliminally presenting emotional faces: In a novel version of the Go/NoGo paradigm, participants made speeded button-press responses to Go targets, withheld responses to NoGo targets, and made spontaneous, free choices to execute or withhold the response for Choice targets. Before each target, we presented emotional faces, backwards masked to render them nonconscious. In Intentional trials, subliminal angry faces made participants more likely to voluntarily withhold the action, whereas fearful and happy faces had no effects. In a second experiment, the faces were made supraliminal, which eliminated the effects of angry faces on volitional choices. A third experiment measured neural correlates of the effects of subliminal angry faces on intentional choice using EEG. After replicating the behavioural results found in Experiment 1, we identified a frontal-midline theta component-associated with cognitive control processes-which is present for volitional decisions, and is modulated by subliminal angry faces. This suggests a mechanism whereby subliminally presented "threat" stimuli affect conscious control processes. In summary, nonconscious perception of angry faces increases choices to inhibit, and subliminal influences on volitional action are deep seated and ecologically embedded.

  14. Voice and choice by delegation.

    van de Bovenkamp, Hester; Vollaard, Hans; Trappenburg, Margo; Grit, Kor

    2013-02-01

    In many Western countries, options for citizens to influence public services are increased to improve the quality of services and democratize decision making. Possibilities to influence are often cast into Albert Hirschman's taxonomy of exit (choice), voice, and loyalty. In this article we identify delegation as an important addition to this framework. Delegation gives individuals the chance to practice exit/choice or voice without all the hard work that is usually involved in these options. Empirical research shows that not many people use their individual options of exit and voice, which could lead to inequality between users and nonusers. We identify delegation as a possible solution to this problem, using Dutch health care as a case study to explore this option. Notwithstanding various advantages, we show that voice and choice by delegation also entail problems of inequality and representativeness.

  15. Mental Toughness Moderates Social Loafing in Cycle Time-Trial Performance.

    Haugen, Tommy; Reinboth, Michael; Hetlelid, Ken J; Peters, Derek M; Høigaard, Rune

    2016-09-01

    The purpose of this study was to determine if mental toughness moderated the occurrence of social loafing in cycle time-trial performance. Twenty-seven men (Mage = 17.7 years, SD = 0.6) completed the Sport Mental Toughness Questionnaire prior to completing a 1-min cycling trial under 2 conditions: once with individual performance identified, and once in a group with individual performance not identified. Using a median split of the mental toughness index, participants were divided into high and low mental toughness groups. Cycling distance was compared using a 2 (trial) × 2 (high-low mental toughness) analysis of variance. We hypothesized that mentally tough participants would perform equally well under both conditions (i.e., no indication of social loafing) compared with low mentally tough participants, who would perform less well when their individual performance was not identifiable (i.e., demonstrating the anticipated social loafing effect). The high mental toughness group demonstrated consistent performance across both conditions, while the low mental toughness group reduced their effort in the non-individually identifiable team condition. The results confirm that (a) clearly identifying individual effort/performance is an important situational variable that may impact team performance and (b) higher perceived mental toughness has the ability to negate the tendency to loaf.

  16. Investigation of impact toughness of a Ni-based superalloy at elevated temperature

    Yang, Y.H.; Yu, J.J.; Sun, X.F.; Jin, T.; Guan, H.R.; Hu, Z.Q.

    2012-01-01

    Highlights: ► The samples show highest impact toughness at 600 °C. ► The impact toughness of samples impact at 760 °C drops sharply. ► The voids nucleation and growth are fracture mechanism at elevated temperature. ► The decrease in strength of grain boundaries causes reduction in impact toughness. -- Abstract: The impact toughness of M951 alloy is investigated in temperature range between 20 °C and 800 °C. The results show that the impact toughness of samples impacted at 600 °C shows highest impact toughness value, the impact toughness value drops sharply when the samples impacted at 760 °C. In addition samples impacted at 800 °C show the higher impact toughness than that of samples impact at 760 °C. The scanning electron microscope observations show that cracks initiate at carbides particles due to high stress concentration, which leads to low impact toughness value at 20 °C. The dimples which can absorb more energy are formed during the impact at 600 °C. The samples impacted at 760 °C show lowest impact toughness. Additionally, the dimples nucleation, growth and coalescence are the major fracture mechanism at elevated temperature.

  17. Air-tough: A fully 3-dimensional linking of atmosphere with soil using eddy diffusivity concept and V-TOUGH

    Montazer, P. [Multimedia Environmental Technology, Inc., Newport Beach, CA (United States)

    1995-03-01

    In arid climates, evapotranspiration is a strongly-coupled thermodynamic process that is controlled by the interaction of the atmospheric boundary layer and the upper soil surface. Simulation of this process requires a fully-coupled thermodynamic multi-phase fluid-flow and energy-transport code. Such a code was developed in a previous investigation using V-TOUGH. The resulting efficient computer code, A-TOUGH, simulates the effect of dynamic atmospheric fluctuations on vapor movement between the soil and the atmosphere and the resulting moisture movement in the soil. However, the coupling between the atmosphere and soil employed eddy diffusivity which was only a function of time and not a function of space. In the present study the code is extended to allow spatial as well as temporal variation of eddy diffusivity.

  18. The use of TOUGH2/iTOUGH2 in support of the Yucca Mountain Project: Successes and limitations

    Bodvarsson, G.S.; Birkholzer, J.T.; Finsterle, S.; Liu, H.H.; Rutqvist, J.; Wu, Y.S.

    2003-01-01

    The TOUGH2/iTOUGH2 family of codes is being used to analyze various processes and phenomena in the unsaturated zone at the proposed high-level nuclear waste repository at Yucca Mountain, Nevada. Various models have been developed that help quantify properties of the volcanic tuffs, water flow, seepage into drifts, and thermally driven coupled processes arising from the heat emitted by radioactive waste. These models are based on various assumptions and approximations that are generally accepted in the literature, but can give rise to different degrees of uncertainty. Some of the key approaches utilized include the continuum approximation, the van Genuchten formulation, the active fracture model, and homogeneous sublayers. These and other approximations are presented separately for the five different models considered, and the resulting levels of uncertainty are discussed

  19. Development of fracture toughness test method for nuclear grade graphite

    Chang, C. H.; Lee, J. S.; Cho, H. C.; Kim, D. J.; Lee, D. J. [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

    2006-02-15

    Because of its high strength and stability at very high temperature, as well as very low thermal neutron absorption cross-section, graphite has been widely used as a structural material in Gas Cooled Reactors (GCR). Recently, many countries are developing the Very High Temperature gas cooled Reactor (VHTR) because of the potentials of hydrogen production, as well as its safety and viable economics. In VHTR, helium gas serves as the primary coolant. Graphite will be used as a reflector, moderator and core structural materials. The life time of graphite is determined from dimensional changes due to neutron irradiation, which closely relates to the changes of crystal structure. The changes of both lattice parameter and crystallite size can be easily measured by X-ray diffraction method. However, due to high cost and long time of neutron irradiation test, ion irradiation test is being performed instead in KAERI. Therefore, it is essential to develop the technique for measurement of ion irradiation damage of nuclear graphite. Fracture toughness of nuclear grade graphite is one of the key properties in the design and development of VHTR. It is important not only to evaluate the various properties of candidate graphite but also to assess the integrity of nuclear grade graphite during operation. Although fracture toughness tests on graphite have been performed in many laboratories, there have been wide variations in values of the calculated fracture toughness, due to the differences in the geometry of specimens and test conditions. Hence, standard test method for nuclear graphite is required to obtain the reliable fracture toughness values. Crack growth behavior of nuclear grade graphite shows rising R-curve which means the increase in crack growth resistance as the crack length increases. Crack bridging and microcracking have been proposed to be the dominant mechanisms of rising R-curve behavior. In this paper, the technique to measure the changes of crystallite size and

  20. Bone toughness at the molecular scale: A model for fracture toughness using crosslinked osteopontin on synthetic and biogenic mineral substrates.

    Cavelier, S; Dastjerdi, A K; McKee, M D; Barthelat, F

    2018-05-01

    The most prominent structural components in bone are collagen and mineral. However, bone additionally contains a substantial amount of noncollagenous proteins (most notably of the SIBLING protein family), some of which may act as cohesive/adhesive "binders" for the composite hybrid collagen/mineral scaffolding, whether in the bulk phase of bone, or at its interfaces. One such noncollagenous protein - osteopontin (OPN) - appears to be critical to the deformability and fracture toughness of bone. In the present study, we used a reconstructed synthetic mineral-OPN-mineral interface, and a biogenic (natural tooth dentin) mineral/collagen-OPN-mineral/collagen interface, to measure the fracture toughness of OPN on mineralized substrates. We used this system to test the hypothesis that OPN crosslinking by the enzyme tissue transglutaminase 2 (TG2) that is found in bone enhances interfacial adhesion to increase the fracture toughness of bone. For this, we prepared double-cantilever beam substrates of synthetic pure hydroxyapatite mineral, and of narwhal dentin, and directly apposed them to one another under different intervening OPN/crosslinking conditions, and fracture toughness was tested using a miniaturized loading stage. The work-of-fracture of the OPN interface was measured for different OPN formulations (monomer vs. polymer), crosslinking states, and substrate composition. Noncrosslinked OPN provided negligible adhesion on pure hydroxyapatite, whereas OPN crosslinking (by the chemical crosslinker glutaraldehyde, and TG2 enzyme) provided strong interfacial adhesion for both hydroxyapatite and dentin using monomeric and polymeric OPN. Pre-coating of the substrate beams with monomeric OPN further improved the adhesive performance of the samples, likely by allowing effective binding of this nascent OPN form to mineral/matrix components, with this pre-attachment providing a protein layer for additional crosslinking between the substrates. Copyright © 2018 Elsevier Inc