The immunology of falciparum malaria, the lethal type of human malaria, has been transformed by two developments. First, a culture system for the asexual blood stages of Plasmodium falciparum.1 Secondly, the cloning and expression of genes coding for a large number of the protein antigens of this malaria parasite over the past two years. Data on proteins, protein antigens and epitopes of P. falciparum supplied by gene cloning techniques have been supplemented by monoclonal antibody approaches, peptide synthesis, and high‐resolution immunochemistry.

Alpha‐fetoprotein (AFP)AFP, alpha‐fetoprotein; T3R, thyroid hormone (triiodothyronine) receptor; RAR, retionic acid receptor; erbA, putative thyroid hormone receptor proto‐oncogene products; VDR, vitamin D receptor; MR, mineralocorticoid receptor; GR, glucocorticoid receptor; PR, progesterone receptor; AR, androgen receptor; HRE, hormone response element on DNA; RXR, retionic‐X‐receptor; RAP, receptor auxiliary (accessory) proteins; E, estrogen. is a tumor‐associated fetal marker, associated both with tumor growth and with birth defects. AFP, whose precise function is unknown, has been classified as belonging to a protein superfamily together with (...) albumin and vitamin D‐binding (Gc) protein. AFP has been shown to bind various ligands in vitro including fatty acids, estrogens, thyroid hormones and retinoic acids. The steroid/thyroid nuclear receptor superfamily of proteins has recently become a major focus of biomedical investigation regarding regulation of gene expression. These receptors are thought to bind to DNA‐hormone response elements (HRE) that affect growth, development, differentiation, reproduction and homeostasis. The HREs are known to share DNA sequences with the various members of the nuclear receptor superfamily. In the present report, the possibility of a leucine‐zipper dimerization (heptad) motif in the carboxy‐terminal third domain of both rodent and human AFP is postulated. The presence of nine such hydrophobic repeats in the third domain of the AFP molecule mimics the heptad dimerization repeats found in the retinoic acid, thyroid, e‐erbA and other members of the nuclear receptor superfamily. Computer analysis revealed that the most conservative matching occurred between AFP and the retinoic acid class of receptors. However, other superfamily members displayed 40–60% homology with 5 of 9 AFP heptads. These findings could provide a possible mechanism for explaining the growth‐regulatory properties (both inhibition and enhancement) that have been ascribed to AFP in the last decade. (shrink)

Meditation has been for long time avoided as a scientific theme because of its complexity and its religious connotations. Fortunately, in the last years, it has increasingly been studied within different neuroscientific experimental protocols. Attention and concentration are surely among the most important topics in these experiments. Notwithstanding this, inhibition of emotions and discursive thoughts are equally important to understand what is at stake during those types of mental processes. I philosophically and technically analyse and compare results from neuroimaging studies, (...) produced by leading authorities on the theme, dealing with two types of meditation: "one-pointed concentration" and "compassion meditation". Analysing "one-pointed concentration", I show the differences between novice and expert meditation practitioners in terms of brain activity and connectivity, considering the relationship among increased attention and concentration and decreased activity in areas related to discursive thought and emotion. Analysing "compassion meditation", I show the importance of the limbic circuitry in emotion sharing. I follow the same strategy of comparing novice and expert meditation practitioners. The conclusion establishes a common structure to those different ways of dealing with emotion during meditation. (shrink)

Decision-making is an intricate subject in neuroscience. It is often argued that laboratorial research is not capable of dealing with the necessary complexity to study the issue. Whereas philosophers in general neglect the physiological features that constitute the main aspects of thought and behaviour, I advocate that cutting-edge neuroscientific experiments can offer us a framework to explain human behaviour in its relationship with will, self-control, inhibition, emotion and reasoning. It is my contention that self-control mechanisms can modulate more basic stimuli. (...) Assuming the aforementioned standpoints, I show the physiological mechanisms underlying social assessment and decision-making. I also establish a difference between veridical and adaptive decision-making, useful to create experimental designs that can better mimic the complexity of our day-by-day decisions in more ecologically relevant laboratorial research. Moreover, I analyse some experiments in order to develop an epistemological reflection about the necessary neural mechanisms to social assessment and decision-making. (shrink)

Die Debatten zu den Themen Physikalismus, Willensfreiheit und Künstliche Intelligenz stehen seit einigen Jahren im Mittelpunkt der Philosophie des Geistes. In den Debatten um den Physikalismus geht es dabei u.a. um folgende Fragen: Lässt sich alles, was es gibt, physikalisch erklären - auch der menschliche Geist? Lässt sich alles auf das Physische reduzieren? Ist der Bereich des Physischen kausal geschlossen? Realisiert das Physische das Mentale? Wie lässt sich mentale Verursachung erklären? In den Debatten um Willensfreiheit fragt man sich: Sind wir (...) physikalisch determiniert? Können wir freie Entscheidungen treffen? Sind wir für unsere Handlungen verantwortlich? Wie verhalten sich Freiheit und Determinismus zueinander? Welchen Beitrag kann die empirische Forschung leisten? In den Debatten um Künstliche Intelligenz werden diese Fragen verhandelt: Können Maschinen denken? Unterscheiden sich Menschen von Maschinen? Sind uns Computer geistig überlegen? Stellt maschinelle Intelligenz ein Modell für menschliche Kognition dar? Welchen wissenschaftlichen Nutzen kann Künstliche Intelligenz haben? Zu jedem der drei Themen Physikalismus, Willensfreiheit und Künstliche Intelligenz bietet das Buch drei Originalbeiträge von renommierten Wissenschaftlern verschiedener Disziplinen sowie jeweils einen kritischen Kommentar. Auf diese Weise soll deutlich werden, dass die drei Themen nicht nur eng miteinander zusammenhängen, sondern auch interdisziplinär von großem Interesse sind. (shrink)

The notion of a weak Messianic power serves as the focal point for this study of theological, materialist, poetic, and post-Freudian psychoanalytic approaches to time and the historical unconscious in the work of Benjamin, Celan and Derrida.

We present a logic to model the behaviour of an agent trusting or not trusting messages sent by another agent. The logic formalises trust as a consistency checking function with respect to currentl...

The King Report on Corporate Governance (1994) evoked unprecedented interest in corporate governance in South Africa. This does not mean that corporate governance was not an issue of concern before the release of this historical report. To the contrary, corporate governance in its broader sense has been at stake since the inception of the first publicly owned companies in South Africa. This article intends to give an overview of corporate governance in South Africa. It starts by making a distinction between (...) broad and narrow conceptions of corporate governance. Before applying this distinction to the practice of corporate governance in South Africa, a brief overview of the corporate landscape in South Africa is provided. Then the South African situation with regard to broad and narrow corporate governance respectively is analysed. The article ends with a discussion of the review of corporate governance that currently is in the making in South Africa. Throughout the article both the financial and ethical dimensions of corporate governance is attended to. (shrink)

In his target paper, John Welwood tells us that we have to beware of 'spiritual bypassing -- using spiritual ideas and practices to sidestep personal, emotional -- unfinished business--, to shore up a shaky sense of self, or to belittle basic needs, feelings, and develop-mental tasks, all in the name of enlightenment'. It's arguable that there is an equal danger of 'narrative bypassing' -- using the idea of one's life as a narrative to 'sidestep personal, emotional --unfinished business--, to shore (...) up a shaky sense of self -- all in the name of' a good life. (shrink)

Many different modes of definition have been proposed over time, but none of them allows for circular definitions, since, according to the prevalent view, the term defined would then be lacking a precise signification. I argue that although circular definitions may at times fail uniquely to pick out a concept or an object, sense still can be made of them by using a rule of revision in the style adopted by Anil Gupta and Nuel Belnap in the theory of truth.

The problems of this passage were concisely stated by M. Platnauer more than thirty years ago and his suggestions for their solution have been adopted and developed in A. S. F. Gow's magnum opus. Its authority—so the present writer suspects—is liable at this point to eclipse the meaning of the text.

The conceptual framework of behaviorism is reconstructed in a logical scheme rather than along chronological lines. The resulting reconstruction is faithful to the history of behaviorism and yet meets the contemporary challenges arising from cognitive science, psycholinguistics, and philosophy. In this reconstruction, the fundamental premise is that psychology is to be a natural science, and the major corollaries are that psychology is to be objective and empirical. To a great extent, the reconstruction of behaviorism is an elaboration of behaviorist views (...) of what it is for a science to be objective and empirical. The reconstruction examines and evaluates behaviorist positions on observation and the rejection of introspection, the behavioral data language, theory construction, stimulus-response psychology, the organization of behavior, complex processes, agency, and the interpretation of mentalistic language. The resulting reconstruction shows behaviorism to be a pragmatic psychological version of positivism based on a behavioral epistemology. (shrink)