Affective variables have been shown to impact working memory and cognitive control. Theoretical arguments suggest that the functional impact of emotion on cognition might be mediated through shifting action dispositions related to changes in motivational orientation. The current study examined the effects of positive and negative affect on performance via direct manipulation of motivational state in tasks with high demands on cognitive control. Experiment 1 examined the effects of monetary reward on task-switching performance, while Experiment 2 examined the effects of (...) both rewards and punishments on working memory, using primary (liquid) reinforcers. In both experiments, dissociable trial-by-trial and contextual (block-related) enhancements of cognitive control during task performance were observed in relationship to motivational incentive value. Performance enhancements were equivalent in the reward and punishment conditions, but were differentially impacted by individual difference measures of trait reward and punishment sensitivity. Together, the results suggest both common and specific mechanisms by which approach and avoidance motivational states influence cognitive control, via activation of reward and punishment processing systems. (shrink)

Die Frequenzkurven, die die lebendige Substanz charakterisieren, können als eine statische Beschreibung oder als das Ergebnis einer Entwicklung betrachtet werden.Im ersten Falle akzeptiert man ohne weiteres die gegebenen Verteilungen und man versucht, ihnen durch mathematische Gleichungen, die keine unmittelbare Wirklich-keitsbedeutung haben, nahezukommen. Das kausale Denken wird hier ausgeschaltet oder man gibt sich wenigstens mit nur sehr groben Analogien zufrieden.Verschiedene Methoden über die Genese der Frequenzkurven werden besprochen; dabei wird gezeigt, dass die Mehrheit der Fälle auf Hypothesen beruht, die biologisch wenig (...) begründet sind. Eine Ausnahme davon macht die Theorie vonJ. C. Kapteyn, weil er den Vorgang des Wachstums in die Genese einbezieht. Seine Methode weiter ausbauend kann man sich vorstellen, dass die Genese einer Frequenzkurve in erblich homogenem Pflanzenmaterial durch Variation der Wachstumsgeschwindigkeit zustandekommt.Auf solche Weise kann man in einem Koordinatensystem mit Länge und Zeit als Koordinaten ein “Deviationsraster” konstruieren.In einem experimentell untersuchten Fall ergab die graphische Methode mit völlig ausreichender Genauigkeit die schon gefundene Frequenz.Les courbes de fréquence qui caractérisent la matière vivante, peuvent être considérées ou comme une description statique ou bien comme le produit d'un développement.Dans le premier cas on accepte les distributions obtenues et on essaie de s'en rapprocher par des équations mathématiques qui n'ont pas une réalité effective. On ne recherche plus la causalité ou alors on se contente le plus souvent d'analogies très grossières.Les auteurs traitent des diverses méthodes de la genèse des courbes de fréquence et démontrent que la plupart des cas reposent sur des hypothèses qui ont peu de fond biologique. La théorie deM. J. C. Kapteyn fait exception parcequ'il introduit le processus de croissance dans la genèse. En poursuivant plus loin dans sa méthode on peut se figurer que la genèse d'une courbe de fréquence de plantes homogènes par hérédité s'expliquerait par des variations de vitesse de croissance.De cette façon on peut construire une “grille de déviation” dans un système en prenant longueur et temps comme coordonnées.Dans un cas essayé expérimentalement ce graphique donnait avec une exactitude assez grande la distribution de fréquence déjà trouvée. (shrink)

© 2015 Elsevier Inc.Toxoplasma gondii is a protozoan pathogen in the phylum Apicomplexa that resides within an intracellular parasitophorous vacuole that is selectively permeable to small molecules through unidentified mechanisms. We have identified GRA17 as a Toxoplasma-secreted protein that localizes to the parasitophorous vacuole membrane and mediates passive transport of small molecules across the PVM. GRA17 is related to the putative Plasmodium translocon protein EXP2 and conserved across PV-residing Apicomplexa. The PVs of GRA17-deficient parasites have aberrant morphology, reduced permeability to (...) small molecules, and structural instability. GRA17-deficient parasites proliferate slowly and are avirulent in mice. These GRA17-deficient phenotypes are rescued by complementation with Plasmodium EXP2. GRA17 functions synergistically with a related protein, GRA23. Exogenous expression of GRA17 or GRA23 alters the membrane conductance properties of Xenopus oocytes in a manner consistent with a large non-selective pore. Thus, GRA17 and GRA23 provide a molecular basis for PVM permeability and nutrient access. (shrink)

The theory of cultural evolution proposed by economist Friedrich August von Hayek is without doubt the most harshly criticized component in his highly prolific intellectual corpus. Hayek depicted the emergence of the market order as the unintended consequence of an evolutionary process in which groups whose rules of behavior led to a comparative increase in population and wealth were favored over others. Key to Hayek’s theory was the claim that the rules of the market, on which modern civilization relies, evolved (...) at the meta-individual level and therefore surpass human reason. Hayek believed that his theory provided scientific explanation for the superiority of the market order over rational planning. In this article, I conduct a selective comparison between Hayek’s and Darwin’s theories of cultural group selection and analyze the role that demographic growth and reason play in their respective accounts. I first present Hayek’s theory of cultural group selection, its sources of inspiration, and its important place in his intellectual legacy. I then compare Hayek’s claims to Darwin’s views and highlight fundamental differences in their evaluation of the role of reason in moral evolution. Finally, I offer some comments concerning the place assigned to demographic growth in Hayek’s theory and his over-reliance on economics in explaining cultural evolution. (shrink)

This paper challenges T. S. Gendler's notion of aliefs, a novel kind of mental state which she introduces to explain a wide variety of belief-discordant behaviors. In particular, I argue that many of the cases which she uses to motivate such a mental state can be fully explained by accounts that make use only of commonplace attitudes such as beliefs and desires.

In lieu of an abstract, here is a brief excerpt of the content:Reviewed by:Die Vorsokratiker: Ein philosophisches Portrȧt by Thomas BuchheimIstván BodnárThomas Buchheim. Die Vorsokratiker: Ein philosophisches Portrȧt. München: C.H. Beck, 1994. Pp. 262. Paper, DM 48.00.This book is a continuous narrative of highlights of presocratic philosophy. The vista offered by Buchheim is revisionary. The presocratics are behind a curve of the road of the philosophical enterprise. What we usually perceive is a mirage created by the doxographic tradition, emanating (...) ultimately from Aristotle. This much might be uncontroversial: the history of presocratic philosophy has been for the last two centuríes a continuous effort to liberate the remains of those early philosophers from the imputations of later authors. But Buchheim’s project is more ambitious than our ordinary occupation with the presocratics. He postulates a specific, markedly presocratic type of appropriation of the world, and then uses this as a yardstick to elicit a new understanding of the mutilated body of the early texts. Presocratic thought is not theoretical, but rather reactive; it cannot extricate itself from the situation in which it is directed at its object.While some of his discussion is perceptive, the chapters abound in idiosyncratic interpretations. It will suffice to mention only a few of Buchheim’s central claims by way of illustration. Although it has been widely held that Anaximander’s apeiron is not only boundless, but also indefinite, Buchheim’s contention that it should be seen as a disorienting and chaotic matrix which provides no foothold for the discerning and distinguishing mind overshoots the mark. This claim does not mesh well with the allowance in Anaximander that there can be a plurality of simultaneous worlds. There can be a disorienting extension beyond the single cosmos, but several (and as some testimonies would claim, evenly distanced) worlds cannot possibly be separated by a medium which defies the notion of extension altogether.Few will be convinced by Buchheim’s claim that Heraclitus did not formulate a doctrine of opposites because he, coming before Parmenides, could have had only a conception of “counteractive parties in an originally unifying contention” (82), since Heraclitus’ provocative pronouncements would thereby be diluted into mere platitudes. Since Empedocles never calls his rhizömata elements, Buchheim impugns the Empedoclean origin of the four element doctrine. For this he needs to explain away much of the evidence of the fragments. Some of the images Empedocles deploys would suggest a mere juxtaposition of the ingredients, some might indicate some more intimate bond arising between these. As Buchheim aptly notes, the choice in this matter is not obvious. Nevertheless there are places where Buchheim’s interpretation is at a serious disadvantage. Empedocles B8, on the standard reading would rule out the [End Page 521] notion of a phusis (growth, generation) or teleutë- (end, perishing) of any mortal thing, and would allow for the mixιs (mixing) and diallaxιs (separation) of what is mixed together. Immortal things, devoid of generation and perishing by default, are understandably not taken into account here. On Buchheim’s reading, however, Empedoclean rhizömata would be allowed to grow, and hence, by a similar reasoning, to perish.In Chapter 5, Buchheim accuses Aristotle of systematically replacing the dynamically loaded expressions of the ancient atomists, characterizing the ultimate building blocks of nature, with static, geometric idioms. The sole exception where Aristotle does not rob the atomists of this dynamic conception of atomic nature, Buchheim claims, is Physics 8.9 265b23ff. But the uniqueness of the passage rests on Buchheim’s idiosyncratic translation. On the standard interpretation (going back at least to Simplicius) Aristotle asserts only that, according to the atomists, nature performs local motion, and not—as Buchheim would have it—that the nature of the atoms is the very performing of local motion.Contrary to Buchheim’s general characterization of presocratic thought as imbued or integrated with the circumstances of cognition, Anaxagoras’ nous is pure and distinct, not mixed with any other ingredient of the universe. For this reason, Buchheim in his final chapter presents Anaxagoras as a transitional figure between presocratic thought and later, classical metaphysics. The details of this claim, just like the overall characterization of the presocratics, are bound... (shrink)

Nomina Sacra : Versuch einer Geschichte der christlichen Kürzung. Von Ludwig Traube, o. ö. Professor der Philologie an der Universitat, München. . Munich: C. H. Beck'sche Verlagsbuchhandlung. 1907. Pp. x + 295. M. 15.Vorlesungen und Abhandlungen. Von Ludwig Traube. Herausgegeben von Franz Boll. Erster Band. Zur Paläographie und Handschriftenkunde. Herausgegeben von Paul Lehmann. Mit biographischer Einleitung von Franz Boll. Munich: C. H. Beck'sche Verlagsbuchhandlung. 1909. Pp. lxxv+263.

It has recently been argued that hope is polysemous in that it sometimes refers to hoping and other times to being hopeful. That it has these two distinct senses is reflected in the observation that a person can hope for an outcome without being hopeful that it will occur. Below, I offer a new argument for this distinction. My strategy is to show that accepting this distinction yields a rich account of two distinct ways in which hope can be lost, (...) ways that map onto the two senses of hope: A person can lose hope either by ceasing to hope for an outcome (hopelessness) or by ceasing to be hopeful that it will obtain (despair). Thinking about these negative attitudes in these two ways, I contend, is explanatorily rich and fruitfully reveals how they differ in phenomenology, behavioral differences, and the ways in which a person can escape them. (shrink)

Physicians have an ethical responsibility to their patients to offer the best available medical care. This responsibility conflicts with their role as gatekeepers of the limited health care resources available for all patients collectively. It is ethically untenable to expect doctors to face this trade-off during each patient encounter; the physician cannot be expected to compromise the wellbeing of the patient in the office in favour of anonymous patients elsewhere. Hence, as in other domains of public policy where individual and (...) collective interests conflict, some form of collective solution is required. Collective solutions may take the form of placing explicit resource constraints on resources available to physicians, or clinical practice guidelines that recognise cost-effective care as acceptable. Such solutions will be politically and ethically sustainable only if patients as citizens of the larger population accept the need for rationing of limited resources in health care. (shrink)

The answer to philosophical questions will often depend on the position one takes regarding the fact-value problem. It is, therefore, not surprising that, in the tradition of western philosophy, the past 200 years or so record an animated discussion of it. In the present collection the debate is continued by representatives of various "schools" in contemporary western thought. A number of philosophers from non-western cultures, too, enter into it. The contributions do not all reflect on the same theme, nor do (...) they use the same approach. Essays written by philosophers sympathetic to the analytical tradition are followed by reflections on the part of those inspired by phe nomenology. A third group of contributions is by non-western thinkers, who are more likely to approach the problem in terms of culture. Their engage ment with the issue clearly shows, among other things, that it is almost exclusively in the western tradition that the fact-value distinction is often understood as an outright dichotomy. The occasion for the publication of this collection is Dr. Cornelis Anthonie van Peursen's retirement as Professor of Philosophy. This year he leaves the Free University, Amsterdam; until 1982 he was professor at the University of Leyden as well. In the Netherlands and beyond he has become known for his concern with constructive comparison of diverging philosophical trends and the cross-cultural fertilization of thought. Characteristic of his career are his efforts to render the results of academic philosophizing understand able to a broader audience. (shrink)

Today's modern car is an assemblage of mechanical and digital components, of metal panels that comprise its structure and silicon chips that run its functions. Communication and information studies scholars have interrogated the problematic aspects of the programs that run those functions, revealing serious issues surrounding privacy and security, worker surveillance, and racial, gendered, and class-based bias. This article contributes to that work by taking a step back and asking about the issues inherent not in the software running on these (...) chips, but on the microchips themselves. Using the lens of “chipification”—the process by which a device is rendered capable of reading and processing data through the embedding of microchips—this article explores how the integration of microchips also involves processes that are often borne from, replicate, or create troubling power dynamics of their own. It takes light-duty passenger vehicles as a case study into how chipification is radically reshaping such processes as resource allocation, labor flows, and cultural practices around car manufacture, use, repair, and modification. By naming the process of chipification, this article allows researchers to identify and analyze the ways that integrating data processing capabilities into everyday devices is not a frictionless practice, but rather one that implicates a variety of power dynamics within these massive industries. (shrink)

These volumes provide a large introduction to the works of modern value theory from their beginnings in J. Bentham, F. Nietzsche, and H. Lotze to the more recent Anglo-American studies. Volume I is concerned with "the German-Language Group." Extensive discussion is devoted to the views of F. Brentano, A. Meinong, C. von Ehrenfels, J. C. Kreibig, E. Heyde, H. Rickert, H. Münsterberg, M. Scheler, K. Wiederhold, W. Stern, F. Wilken, M. Beck, and V. Krafts. It provides a good conspectus (...) of varieties of nineteenth century value theories. The author aims at an exposition rather than critical treatment of the various philosophers. Each chapter contains a useful bibliography. Of more contemporary interest is Volume II which deals with the Anglo-American Group. One finds here a detailed presentation of the theories of W. M. Urban, J. Dewey, B. Bosanquet, D. Prall, C. G. Shaw, R. B. Perry, D. H. Parkel, W. Stern, A. C. Garnett, J. N. Findlay, E. Brightman, B. E. Jessup, C. I. Lewis, R. Lepley, S. C. Pepper, Everett Hall, R. Hartman, and W. D. Lamont. Shorter discussions deal with works of A. L. Hillard, E. M. Adams, and K. Aschenbrenner. Liberal quotations from original sources are interspersed throughout the exposition. The clarification of issues is not always successful. The author does provide a good focus, however, for important passages from the works discussed. Regrettably, one finds an omission of the view of David Pole, the absence of a summary section on each theory discussed, and the absence of an index. Nevertheless, the students of value theory can find in this work a useful tool of research. The comprehensive scope provides a rich variety of contributions to the important field of value theory.—A.S.C. (shrink)

The requirement of gauge invariance for the Schwinger-DeWitt equations, interpreted as a manifestly covariant quantum theory for the evolution of a system in spacetime, implies the existence of a five-dimensional pre-Maxwell field on the manifold of spacetime and “proper time” τ. The Maxwell theory is contained in this theory; integration of the field equations over τ restores the Maxwell equations with the usual interpretation of the sources. Following Schwinger's techniques, we study the Green's functions for the five-dimensional hyperbolic field equations (...) for both signatures ± [corresponding to O(4, 1) or O(3, 2) symmetry of the field equations] of the proper time derivative. The classification of the Green's functions follows that of the four-dimensional theory for “massive” fields, for which the “mass” squared may be positive or negative, respectively. The Green's functions for the five-dimensional field are then given by the Fourier transform over the “mass” parameter. We derive the Green's functions corresponding to the principal part ΔP and the homogeneous function Δ 1 ; all of the Green's functions can be expressed in terms of these, as for the usual field equations with definite mass. In the O(3, 2) case, the principal part function has support for x2⩾τ2, corresponding to spacelike propagation, as well as along the light cone x2=0 (for τ=0). There can be no transmission ofinformation in spacelike directions, with this propagator, since the Maxwell field, obtained by integration over τ, does not contain this component of the support. Measurements are characterized by such an integration. The spacelike field therefore can dynamically establish spacelike correlations. (shrink)