Two major functions of the visual system are discussed and contrasted. One function of vision is the creation of an internal model or percept of the external world. Most research in object perception has concentrated on this aspect of vision. Vision also guides the control of object-directed action. In the latter case, vision directs our actions with respect to the world by transforming visual inputs into appropriate motor outputs. We argue that separate, but interactive, visual systems have evolved for the (...) perception of objects on the one hand and the control of actions directed at those objects on the other. This 'duplex' approach to high-level vision suggests that Marrian or 'reconstructive' approaches and Gibsonian or 'purposive-animate-behaviorist' approaches need not be seen as mutually exclusive, but rather as complementary in their emphases on different aspects of visual function. (shrink)

The wish to extend the human lifespan has a long tradition in many cultures. Optimistic views of the possibility of achieving this goal through the latest developments in medicine feature increasingly in serious scientific and philosophical discussion. The authors of this paper argue that research with the explicit aim of extending the human lifespan is both undesirable and morally unacceptable. They present three serious objections, relating to justice, the community and the meaning of life.

Background: Discussing treatment risks has become increasingly important in medical communication. Still, despite regulations, physicians must decide how much and what kind of information to present. Objective: To investigate patients’ preference for information about a small risk of a complication of colonoscopy, and whether medical and personal factors contribute to such preference. To propose a disclosure policy related to our results. Design: Vignettes study. Setting: Department of Gastroenterology, Academic Medical Centre, the Netherlands. Patients: 810 consecutive colonoscopy patients. Intervention: A home-sent (...) questionnaire containing three vignettes. Vignettes varied in the indication for colonoscopy, complication severity and level of risk. Patients were invited to indicate their wish to be informed and the importance of such information. In addition, sociodemograhic, illness-related and psychological characteristics were assessed. Main outcome measurements: Wish to be informed and importance of information. Results: Of 810 questionnaires, 68% were returned. Patients generally wished to be informed about low-risk complications, regardless of the indication for colonoscopy or the severity of the complication. The level of risk did matter, though (OR = 2.48, SE = 0.28, p = 0.001). The information was considered less important if done for population screening purposes or diagnosis of colon cancer, if the complication was less severe (bleeding) and if the risk was smaller (0.01% and 0.1%). Patients’ information preference was also related to age, mood and coping style. Limitations: Difficulty of vignettes. Conclusions: Patients generally wish to be informed about all possible risks. However, this might become uninformative. A stepwise approach is suggested. (shrink)

We obtain in this paper a representation of the formulae of extensions ofL by generalized quantifiers through functors between categories of first-order structures and partial isomorphisms. The main tool in the proofs is the back-and-forth technique. As a corollary we obtain the Caicedo's version of Fraïssés theorem characterizing elementary equivalence for such languages. We also discuss informally some geometrical interpretations of our results.

DNA double‐strand breaks (DSBs) are extremely hazardous lesions for all DNA‐bearing organisms and the mechanisms of DSB repair are highly conserved. In the eukaryotic mitotic cell cycle, DSBs are often present following DNA replication while, in meiosis, hundreds of DSBs are generated as a prelude to the reshuffling of the maternally and paternally derived genomes. In both cases, the DSBs are repaired by a process called homologous recombinational repair (HRR), which utilises an intact DNA molecule as the repair template. Mitotic (...) and meiotic HRR are managed by ‘checkpoints’ that inhibit cell division until DSB repair is complete. Here we attempt to summarise the substantial recent progress in understanding the checkpoint management of HRR in mitosis (focussing mainly on mammals) and then go on to use this information as a framework for understanding the presumed checkpoint management of HRR in mammalian meiosis. BioEssays 29:974–986, 2007. © 2007 Wiley Periodicals, Inc. (shrink)

The notion of consent which rose to the forefront in biomedical ethics as an attempt to safeguard patients' autonomy, is relatively new. The notion itself requires qualification, for it precludes neither duress nor ignorance. More seriously, I argue here that consent is redundant except in situations where paternalism prevails. Paradoxically, these are the very situations where it may be difficult to uphold or to verify voluntary consent. I suggest that a request-based relationship has the potential to overcome these difficulties. It (...) enhances patients' participation in decision making, requires that the patients remain in command and avoids their subordination. Request is also more conducive to treatments that are representative of patients' own values and perceptions. In practice, what one wants and what one agrees to, often concur. But these are not conceptually identical issues, and they carry important differences of emphasis. (shrink)

Recently in the pages of The Classical Quarterly Mathias Hanses convincingly demonstrated the existence of a fourth occurrence of the programmatic adjective λεπτός in Aratus, Phaen. 783–7. This new example occurs in the form of a diagonal acrostic alongside the known ‘gamma-acrostic’ and the occurrence of the same form of the adjective in line 784. Jerzy Danielewicz has now proposed yet a fifth instance of λεπτή in the form of an acronym spread over two lines and meant to be (...) read anticlockwise. (shrink)

Some ethicists argue that patient confidentiality is absolute and thus should never be broken. I examine these arguments that when critically scrutinised, become porous. I will explore the concept of patient confidentiality and argue that although, this is a very important medical and bioethical issue, this needs to be wisely delivered to reduce third party harm or even detriment to the patient. The argument for absolute confidentiality is particularly weak when it comes to genetic information and inherited disease.

The mammalian pineal gland contains two types of N‐acetyltransferases which act on aromatic amines. One type preferentially acetylates arylamines such as phenetidine and aniline, whereas the other preferentially acetylates arylalkylamines such as tryptamine and phenylethylamine. The two enzymes can be distinguished by (1) molecular size, (2) regulation, and (3) inactivation characteristics. Arylalkylamine N‐acetyltransferase is involved in the regulation of melatonin synthesis in the pineal gland. A specific function of pineal arylamine N‐acetyltransferase has not been established; it may function as a (...) nonspecific detoxification mechanism. (shrink)

En este trabajo se describe un nuevo dispositivo didáctico que estamos diseñando y completando, los Recorridos de Estudio e Investigación (REI), que quieren contribuir a crear secuencias de enseñanza-aprendizaje.

Thomas Kuhn died last June, and with him the last of the great 20th-century\nphilosophers of science passed into history. In order to understand this\nhistory, it is necessary to understand Kuhn’s relationship to what came before\nhim. Logical positivism is what came before Kuhn. And many people misunderstand\nthe relationship between the two. Michael Friedman’s account is\nrepresentative. Friedman writes that the ’official demise of’ logical positivism\n’took place sometime between the publication of W. V Quine’s ’Two Dogmas\nof Empiricism’ (1951), and that of Thomas Kuhn’s (...) The Structure of Scientific\nRevolutions (1962)’.1. (shrink)

Review of Tibebe Eshete, Evangelical Movement in Ethiopia: Resistance and Resilience (Waco Texas: Baylor University Press, 2009), xiii + 480 pp.

Buildings are constructed for accommodating living and industrial needs. Floor cleaning robots have been developed to cater to the demand of these buildings. Area coverage and coverage time are crucial performance factors of a floor cleaning robot. Reconfigurable tiling robots have been introduced over fixed shape robots to improve area coverage in floor cleaning applications compared to robots with fixed morphologies. However, area coverage and coverage time of a tiling robot compromised one another. This study proposes a novel concept that (...) considers the ability of a tiling robot to configure both its morphology and size according to the environment. This concept is inspired by the pleomorphism that could be seen in bacteria. In this regard, P-hTetro, a pleomorphic tiling robot that can reconfigure its morphology and size, is considered. A novel coverage strategy for realizing the size reconfiguration is also proposed. According to this strategy, the robot covers obstacle-free areas with its maximum size, while an obstacle cluster is covered after shrinking to an optimum size. The optimum size for reconfiguration is determined by the genetic algorithm based on the arrangement of the environment. The performance and behavior of the proposed P-hTetro have been compared against that of an existing tiling robot which has a fixed size. According to the statistical outcomes, a tiling robot with the ability to reconfigure its size can significantly improve the performance in the aspects of area coverage and coverage time compared to a tiling robot with no ability to reconfigure its size. (shrink)

An interesting question, in both the moral and the legal context, is whether babies born of an infertility treatment-induced supernumerary pregnancy are properly considered to have been harmed. One might wonder how such a question could even arise in the face of data that clearly demonstrate that ITISP leaves an unduly large number of babies blind, deaf, and palsied, and facing lifelong disabilities. In fact, however, a number of arguments, based on the problem of collective form and two forms of (...) the so-called “nonidentity problem,” challenge the claim of harm in the ITISP context. The purpose of the present paper is to establish, as against these arguments, that harm has been imposed on the ITISP-damaged offspring. (shrink)

Context: Radical Constructivism is an issue that deeply divides the cognitive science community: most researchers reject it, but an increasing number do not. Problem: Constructivists stress that our knowledge starts from experience. Some (“ontic” constructivists) deny the existence of a mind-independent world, while others (“radical” constructivists) claim merely that, if such a world exists, we can know nothing about it. Both positions conflict with scientific realism. It is not clear that the conflict can be resolved. Method: This paper uses philosophical (...) argument to ask whether constructivism can be rationally preferred over realism in science. Results: Ontic constructivism cannot be disproved by any knock-down argument. Nevertheless, it is irrational to accept it, because it ignores the strategy of “inference to the best explanation”: realism is the best explanation of the successes of science. Radical constructivism, too, fails to explain these successes. Some radical constructivists have tried to offer theories more sympathetic to realism. For instance, Ernst von Glasersfeld sees science as a coherent ordering of experience, and appeals to Piagetian psychology as support. There are close similarities. But Piaget was also caught in a constructivist anti-realism, despite his attempt to evade it. Implications: The constructivist’s claim that scientific concepts and theories are generated by human minds is correct. But this important insight should not be used to deny realism, which is the best explanation of the many undeniable successes of science and engineering. (shrink)

African American distrust of medicine has consequences for treatment seeking and healthcare behaviour. Much work has been done to examine acute events that have contributed to this phenomenon and a sophisticated bioethics discipline keeps watch on current practices by medicine. But physicians and clinicians are not the only actors in the medical arena, particularly when it comes to health beliefs and distrust of medicine. The purpose of this paper is to call attention not just to ethical shortcomings of the past, (...) but to the structural contexts of those events and the contributions and responsibilities of popular media and academic disciplines in the production of knowledge. We argue that ignoring context and producing inaccurate work has real impacts on health and healthcare, particularly for African Americans, and thus engenders ethical obligations incumbent on disciplines traditionally recognised as purely academic. (shrink)

Dilts prints c πομπ . Hercher before him adopted the conjecture θεα πομπή . Several pieces of evidence tell in favour of the latter text.

If self-interested behavior conflicts with the collective welfare, rules of cooperation are often installed to prevent egoistic behavior. We hypothesized that installing such rules may instigate personal moral norms of cooperation, but that they fail in doing so when installed by a leader who is self-interested rather than self-sacrificing. Three studies confirmed this and also showed that, consequently, only self-sacrificing leaders were able to install rules that increase cooperation without the need for a perfectly operating monitoring system.