To controlforceaccurately under a wide range of behavioral conditions, the central nervous system would either require a detailed, continuously updated representation of the state of each muscle (and the load against which each is acting) or else force feedback with sufficient gain to cope with variations in the properties of the muscles and loads. The evidence for force feedback with adequate gain or for an appropriate central representation is not sufficient to conclude that force is the major controlled variable in (...) normal limb movements.Morton's hypothesis, thatlengthis controlled by a follow-up servo, has a number of difficulties related to the delays, gains, variability, and specificity in feedback pathways comprising potential servo loops. However, experimental evidence is consistent with these pathways providing servo assistance for some movements produced by coactivation of α- and static γ-motoneurons. Dynamic γ-motoneurons may provide an additional input for adaptive control of different types of movements.The idea that feedback is used to compensate for changes in musclestiffnesshas received experimental support under static postural conditions. However, reflexes tend to increase rather than decrease the range of variation in muscle stiffness during some cyclic movements. Theoretical problems associated with the regulation of stiffness are also discussed. The possibilities of separate control systems forvelocityorviscosityare considered, but the evidence is either negative or lacking. I conclude that different physical variables can be controlled depending on the type of limb movement required. The concept of stiffness regulation is also useful under some conditions, but should probably be extended to the regulation of the visco-elastic properties (i.e., the mechanical impedance) of a muscle or joint. (shrink)

All of our information about the world is derived from the function of our senses, and thus they are the principal source of all our knowledge. This was recognized explicitly by early Greek philosophers, remained an important point of discussion for nineteenth‐century philosophers, and continues to be a key issue for present‐day philosophers, psychologists, and neuroscientists. It is a key issue in cognitive science because, by initiating the processes that store and evaluate information, sensory information transmission can be considered a (...) cognitive initiator. In a very real sense, who we are and how we see the world are the result of the experiences that are mediated by our sensory systems. These are some of the reasons why the study of sensory systems has occupied such a prominent place in modern cognitive neuroscience. (shrink)

Background: There are few standardized measures available to assess executive function in a naturalistic setting for children. The Children’s Cooking Task is a complex test that has been specifically developed to assess EF in a standardized open-ended environment. The aim of the present study was to evaluate the internal consistency, inter-rater reliability, sensitivity and specificity, and also convergent and divergent validity of the Norwegian version of CCT among children with pediatric Acquired Brain Injury and healthy controls.Methods: The present study has (...) a cross-sectional design, based on baseline data derived from a multicenter RCT. Seventy-five children with pABI from two university hospitals with parent-reported executive dysfunction and minimum of 12 months since injury/completed cancer therapy, as well as 59 HCs aged 10–17 years, were assessed with CCT using total errors as the main outcome measure. The pABI group completed tests assessing EF on the impairment level within the ICF framework, and on the participation level. In addition, they completed tests of intellectual ability, processing speed, attention, learning, and memory. Finally, overall functional outcome was evaluated for the children with pABI.Results: Acceptable internal consistency and good inter-rater reliability were found for the CCT. Children with pABI performed significantly worse on the CCT than the HCs. The CCT identified group membership, but the sensitivity and specificity were overall classified as poor. Convergent validity was demonstrated by associations between the CCT and performance-based tests assessing inhibition, cognitive flexibility, and working memory, as well as teacher-reported executive dysfunction. Divergent validity was supported by the lack of association with performance-based measures of learning and memory, attention, and verbal intellectual ability. However, there was a moderate association between the CCT and performance-based tests of processing speed. Lastly, better performance on the CCT was associated with a better functional outcome.Conclusion: Our study with a relatively large sample of children with pABI and HC’s demonstrated good psychometric properties of the CCT. CCT performance was associated with the overall level of disability and function, suggesting that CCT is related to the level of activity in everyday life and participation in society. Hence, our study suggests that the CCT has the potential to advance the assessment of EF by providing a valid analysis of real-world performance. Nevertheless, further research is needed on larger samples, focusing on predictors of task performance, and evaluating the ability of CCT to detect improvement in EF over time. The patterns of error and problem-solving strategies evaluated by the CCT could be used to inform neuropsychological rehabilitation treatmentand represent a more valid outcome measure of rehabilitation interventions. (shrink)

Religious and Ethical Perspectives on Global Migration examines the complicated social ethics of migration in today's world. Editors Elizabeth W. Collier and Charles R. Strain bring the perspectives of an international group of scholars toward a theory of justice and ethical understanding for the nearly two hundred million migrants who have left their homes seeking asylum from political persecution, greater freedom and safety, economic opportunity, or reunion with family members.

However, Stein's self-images are more than appropriations of a male identity and masculine interests. Several of them are irrelevant to categories of sex and gender. In part, Stein is an obsessive psychologist, a Euclid of behavior, searching for "bottom natures," the substratum of individuality. She also tries to diagram psychic genotypes, patterns into which all individuals might fit. Although she plays with femaleness/maleness as categories, she also investigates an opposition of impetuousness and passivity, fire and phlegm; a variety (...) of regional and national types; and the dualism of the "dependent independent," who tends to resist. In part, as she puzzles her way towards knowing and understanding, she presents herself as engaged in aural and oral acts, listening and hearing before speaking and telling. That sense of perception as physical also emerges in a passage in which she, as perceiver/describer, first incorporates and then linguistically discharges the world: "Mostly always when I am filled up with it I tell it, sometimes I have to tell it, sometimes I like to tell it, sometimes I keep on with telling it."1 · 1. The Making of Americans: Being a History of a Family's Progress , p. 325. Catharine R. Stimpson, associate professor of English at Barnard College, is the editor of Signs: Journal of Women in Culture and Society and the author of J.R.R. Tolkien as well as other essays and fiction. See also: "Visual Rhetoric in The Autobiography of Alice B. Toklas" by Paul K. Alkon in Vol. 1, No. 4; "Gertrude Stein, the Cone Sisters, and the Puzzle of Female Friendship" by Carolyn Burke in Vol. 8, No. 3. (shrink)

Qualia have historically been thought to stand in a very different epistemological relation to the knower than does the external furniture of the world. The ‘raw feels’ of thought were often said to be ‘given’, while what we might call the content of that thought – for example, claims about the external world – was thought only more or less doubtfully true; and this was often said to be because we are ‘directly’ or ‘non-inferentially’ confronted by qualia or experiences, whereas (...) all other properties or objects are only mediately ‘connected’ to the perceiver. The modern turn in philosophy – spearheaded by Wittgen-stein, Sellars, Quine, Ryle and others – away from classical empiricism to today’s ‘post-postivistic’ philosophy, has apparently involved the rejection of this once familiar assumption. I argue a) that the rejection of a certain kind of epistemological foundationalism does not entail the rejection of phenomenal individuals tout court; and b) that qualia are in fact, in some epistemologically significant ways, given. (shrink)

In this paper a formalized logic of propositions, PA1, is presented. It is proven consistent and its relationships to traditional logic, to PM ([15]), to subjunctive (including contrary-to-fact) implication and to the “paradoxes” of material and strict implication are developed. Apart from any intrinsic merit it possesses, its chief significance lies in demonstrating the feasibility of a general logic containing theprinciple of subjunctive contrariety, i.e., the principle that ‘Ifpwere true thenqwould be true’ and ‘Ifpwere true thenqwould be false’ are incompatible.

Changes being introduced to deregulate the Dutch health care system after decades of extensive state control are to be welcomed, and will in future require consumers to be ‘well‐informed, cost‐conscious and assertive patients, who are aware of their responsibility for their own health.’ R.B. Kool MD, PhD and E.J.J.M. Kimman PhD are attached to the Department of Business Ethics in the Faculty of Economics and Econometrics at The Free University, P.O. Box 7161, 10107 MC Amsterdam.

Prevalence of contract cheating and outsourcing through organised methods has received interest in research studies aiming to determine the most suitable strategies to reduce the problem. Few studies have presented an international approach or tested which variables could be correlated with contract cheating. As a result, strategies to reduce contract cheating may be founded on data from other countries, or demographics/situations which may not align to variables most strongly connected to engagement in outsourcing. This paper presents the results of a (...) series of statistical analyses aimed at testing which variables were found to be predictors of students’ self-reported formal outsourcing behaviours. The data are derived from an international research study conducted in 22 languages, with higher education students (from Europe, the Americas and Australasia. Analyses found that country and discipline of study as well as the rate at which respondents n = 7806) believed other students to be cheating, were positively correlated to their cheating behaviours. Demographic variables did not show strong statistical significance to predicting contract cheating. (shrink)

The problems presented by the use of named child patients and their medical histories in television, radio and newspapers is discussed. It is suggested that it is not acceptable to regard this as comparable to their participation in non-therapeutic research, and that no one, not even the parent has the authority to give consent to such use.

Many social scientists and philosophers have counted themselves moral relativists in some sense or other. We cannot deal with all the various views which are properly called forms of “moral relativism”; so I propose to explain a form of moral relativism which seems to me an interesting, and somewhat plausible theory. This theory comprises the following three affirmations: The basic moral principles of different individuals or groups sometimes are, or can be, in some important sense conflicting. When there is such (...) fundamental conflict of basic principles or standards, there is either always, or at least sometimes, no way to show that one view is better justified even in the presence of ideally complete factual information; in that sense the principles are equally justified or “valid.” But there is a sense in which a particular moral belief may be mistaken or unjustified, if it is a misapplication of the basic principles of the individual or group, e.g., if the basic principles plus statements of known or knowable facts entail a moral proposition incompatible with it. As stated, moral relativism could be true even though in fact, accidentally, all individuals agree in their basic moral principles. (shrink)

This study examines whether scenic beauty judgments based upon photographs of landscapes are similar to scenic beauty judgments based upon on-site experiences of landscapes. Two concerns are emphasized: a concern about the threat to the ecological validity of photo-based assessments caused by differences between on-site and photo-based contexts and a concern that the individual rater, rather than the group average, is the more appropriate unit of analysis for tests of validity of photo-based assessments. On-site scenic beauty assessments were collected from (...) day hikers. These data were compared to photo-based scenic beauty assessments collected from the same persons three months and nine months after their on-site experience. Approximately 38% of participants had insignificant correlations between their on-site and photo-based scenic beauty ratings. These and other results suggest that the validity of photo-based scenic beauty assessments is in doubt, at least for the situation studied here. Moreover, the results suggest that the difference between persons' on-site and photo-based ratings can be explained, in part, by contextual factors such as the mood, meaning, and novelty that differentiate photo-based from on-site landscape experiences. Group averaged on-site and photo-based assessments, however, were very similar, suggesting caution may be in order for studies interpreting summary measures. (shrink)

It is the aim of this paper to examine certain aspects of a point of view which has attracted much attention in physical methodology. This is the standpoint known as operationalism. We wish to discuss its significance in the construction and interpretation of physical theories.The essential meaning of operationalism in physics is that physical concepts should be defined in terms of actual physical operations. On this view there is no meaning to a concept unless it represents an operation which can (...) be performed in the laboratory. Thus the term “pressure of a gas” signifies nothing until an operation is described which constitutes the measurement of pressure. When one thinks of pressure one must think. of some actual apparatus, such as, for example, some glass and rubber tubing and some mercury and certain operations performed using these until finally one gets a pointer reading which one calls the pressure of the gas. The same stand is taken with respect to length, time, velocity, acceleration, temperature, etc. (shrink)

I describe how gravitational entropy is intimately connected with the concept of gravitational heat, expressed as the difference between the total and free energies of a given gravitational system. From this perspective one can compute these thermodyanmic quantities in settings that go considerably beyond Bekenstein's original insight that the area of a black hole event horizon can be identified with thermodynamic entropy. The settings include the outsides of cosmological horizons and spacetimes with NUT charge. However the interpretation of gravitational entropy (...) in these broader contexts remains to be understood. (shrink)

One area in which the moral philosopher might say something useful for the thinking of economists is that of welfare economics – not by improving formalizations or criticizing proofs as to conditions necessary or sufficient for an optimum situation, much less by suggesting what particular state of society would be optimal. Rather, he can do this by pointing out some distinctions, by suggesting how some terms used by economists can profitably be defined, and by questioning some assumptions which seem to (...) lie behind the thinking of some economists. The following discussion is aimed along these lines. The main goal of the argument will be to produce helpful definitions of “increase the welfare of an individual” and “increase social welfare.”. (shrink)