In order to accomplish the transition from avascular to vascular growth, solid tumours secrete a diffusible substance known as tumour angiogenesis factor (TAF) into the surrounding tissue. Endothelial cells which form the lining of neighbouring blood vessels respond to this chemotactic stimulus in a well-ordered sequence of events comprising, at minimum, of a degradation of their basement membrane, migration and proliferation. Capillary sprouts are formed which migrate towards the tumour eventually penetrating it and permitting vascular growth to take place. It (...) is during this stage of growth that the insidious process of invasion of surrounding tissues can and does take place. A model mechanism for angiogenesis is presented which includes the diffusion of the TAF into the surrounding host tissue and the response of the endothelial cells to the chemotactic stimulus. Numerical simulations of the model are shown to compare very well with experimental observations. The subsequent vascular growth of the tumour is discussed with regard to a classical reaction-diffusion pre-pattern model. (shrink)

The primary aim of this study was to investigate the relation between self-perceived executive functions and the school achievement of young adolescents, while controlling for parental education and sex. We specifically focused on executive aspects of daily life behavior and the higher-order EFs, as measured with self-report, rather than on the more basic EFs which have been the primary focus of prior investigations. In two independent samples of sixth graders, students evaluated their EFs on a self-report questionnaire, the Amsterdam Executive (...) Functioning Inventory. School achievement in the domains of mathematics and reading comprehension were evaluated with nationally used, norm-based achievement tests. Results revealed that the self-perceived EFs of young adolescents were significantly correlated with their school achievement in both study samples. School achievement was also correlated with the level of parental education, but the factor sex did not have such influence. In study 1, self-perceived EFs explained additional variance in school achievement, while controlling for parental education and sex. In study 2, this was only the case for the most robust measure of school achievement, i.e., the end-of-primary-school final achievement test. Furthermore, besides the relation with achievement tests, we also found a relation between self-perceived EFs and teacher ratings behavioral problems in the classroom. Together, our findings imply that young students can properly reflect on the effectiveness and appropriateness of their EFs in a way that is relevant to their academic achievement and classroom behavior. The findings underscore the importance of considering the development of EFs and parental education in the evaluation of academic achievements in early adolescence. (shrink)

Background: Legislation on physician-assisted suicide is being considered in a number of states since the passage of the Oregon Death With Dignity Act in 1994. Opinion assessment surveys have historically assessed particular subsets of physicians.Objective: To determine variables predictive of physicians’ opinions on PAS in a rural state, Vermont, USA.Design: Cross-sectional mailing survey.Participants: 1052 physicians licensed by the state of Vermont.Results: Of the respondents, 38.2% believed PAS should be legalised, 16.0% believed it should be prohibited and 26.0% believed it should (...) not be legislated. 15.7% were undecided. Males were more likely than females to favour legalisation . Physicians who did not care for patients through the end of life were significantly more likely to favour legalisation of PAS than physicians who do care for patients with terminal illness . 30% of the respondents had experienced a request for assistance with suicide.Conclusions: Vermont physicians’ opinions on the legalisation of PAS is sharply polarised. Patient autonomy was a factor strongly associated with opinions in favour of legalisation, whereas the sanctity of the doctor–patient relationship was strongly associated with opinions in favour of not legislating PAS. Those in favour of making PAS illegal overwhelmingly cited moral and ethical beliefs as factors in their opinion. Although opinions on legalisation appear to be based on firmly held beliefs, approximately half of Vermont physicians who responded to the survey agree that there is a need for more education in palliative care and pain management. (shrink)

Residency training in the Netherlands is to be restructured over the coming years. To this end a general competence profile for medical specialists has been introduced. This profile is nearly the same as the Canadian CanMEDS 2000 model, which describes seven general areas of medical specialist competence, one of which is professionalism. In order to establish a training programme for residents and their instructors based on this competence, it is necessary to develop a vision that does justice to everyday medical (...) practice. The two most prevailing views of professionalism—as personal, or as a behavioural characteristic—fall short of this. Only when professionalism is understood as reflective professionalism does it encompass the fundamental contextuality of medical treatment. This means that the focus of training and assessment must be shifted to accountability for treatment. (shrink)

Recent data indicate that under a specific posthypnotic suggestion to circumvent reading, highly suggestible subjects successfully eliminated the Stroop interference effect. The present study examined whether an optical explanation could account for this finding. Using cyclopentolate hydrochloride eye drops to pharmacologically prevent visual accommodation in all subjects, behavioral Stroop data were collected from six highly hypnotizables and six less suggestibles using an optical setup that guaranteed either sharply focused or blurred vision. The highly suggestibles performed the Stroop task when naturally (...) vigilant, under posthypnotic suggestion not to read, and while visually blurred; the less suggestibles ran naturally vigilant, while looking away, and while visually blurred. Although visual accommodation was precluded for all subjects, posthypnotic suggestion effectively eliminated Stroop interference and was comparable to looking away in controls. These data strengthen the view that Stroop interference is neither robust nor inevitable and support the hypothesis that posthypnotic suggestion may exert a top-down influence on neural processing. (shrink)

We describe a novel computational theory of how individuals segment perceptual information into representations of events. The theory is inspired by recent findings in the cognitive science and cognitive neuroscience of event segmentation. In line with recent theories, it holds that online event segmentation is automatic, and that event segmentation yields mental simulations of events. But it posits two novel principles as well: first, discrete episodic markers track perceptual and conceptual changes, and can be retrieved to construct event models. Second, (...) the process of retrieving and reconstructing those episodic markers is constrained and prioritized. We describe a computational implementation of the theory, as well as a robotic extension of the theory that demonstrates the processes of online event segmentation and event model construction. The theory is the first unified computational account of event segmentation and temporal inference. We conclude by demonstrating now neuroimaging data can constrain and inspire the construction of process-level theories of human reasoning. (shrink)

BackgroundHospitalized older adults frequently have impaired cognition and must rely on surrogates to make major medical decisions. Ethical standards for surrogate decision making are well delineated, but little is known about what factors surrogates actually consider when making decisions.ObjectivesTo determine factors surrogate decision makers consider when making major medical decisions for hospitalized older adults, and whether or not they adhere to established ethical standards.DesignSemi-structured interview study of the experience and process of decision making.SettingA public safety-net hospital and a tertiary referral (...) hospital in a large city in the Midwest United States.ParticipantsThe study included 35 surrogates with a recent decision-making experience for an inpatient aged 65 or older.MeasurementsThe key factors that surrogates considered when making decisions. Interview transcripts were coded and analyzed using the grounded theory method of qualitative analysis.ResultsSurrogates considered patient-centered factors and surrogate-centered factors. Patient-centered factors included: respecting the patient’s input, using past knowledge of the patient to infer the patient’s wishes, and consider ing what is in the patient’s best interests. Some surrogates expressed a desire for more information about the patient’s prior wishes. Surrogate-centered factors included: surrogate’s wishes as a guide, surrogate’s religious beliefs and/or spirituality, surrogate’s interests, and family consensus.ConclusionOur study indicates that surrogate decision making is more complex than the standard ethical models, which are limited to considerations of the patient’s autonomy and beneficence. Because surrogates also imagine what they would want under the circumstances and consider their own needs and preferences, models of surrogate decision making must account for these additional considerations. Surrogates’ desire for more information about patients’ preferences suggests a need for greater advance care planning. (shrink)

At the turn of the century Idealism was perhaps the leading school of philosophy in the English-speaking world. By the 1960s the situation was very different. There had occurred during the previous two generations what has been described as 'a revolution in philosophy', one consequence of which had been the almost total eclipse of Idealism. Originally published in 1962, this book is a critical study of certain aspects of the work of four Idealist philosophers: F. H. Bradley, T. H. Green, (...) Bernard Bosanquet and Josiah Royce. It deals mainly with their social philosophy, but some consideration is also given to their metaphysics. It is the thesis of this book that there is a valid and significant form of Idealism to be found in the work of these philosophers, but that they did not succeed in developing it fully and consistently. (shrink)

The traditional Dung networks depict arguments as atomic and study the relationships of attack between them. This can be generalised in two ways. One is to consider various forms of attack, support, feedback, etc. Another is to add content to nodes and put there not just atomic arguments but more structure, e.g. proofs in some logic or simply just formulas from a richer language. This paper offers to use temporal and modal language formulas to represent arguments in the nodes of (...) a network. The suitable semantics for such networks is Kripke semantics. We also introduce a new key concept of usability of an argument. This is the beginning of a continuing research for adding contents to the nodes of an argumentation network. This research will allow us to address notions like ?what does it exactly mean for a node to attack another? or ?what does it mean for a network to be consistent? or ?can we give proper proof rules to manipulate networks?, and more. (shrink)

The same research proposal was submitted to 24 district health authority (DHA) research ethics committees in different parts of the country. The objective was to obtain permission for a multi-centre research project. The study of neonatal care in different types of unit (regional, subregional and district), required that four health authorities were approached in each of six widely separated health regions in England. Data were collected and compared concerning aspects of processing, including application forms, information required, timing and decision-making. The (...) key finding was that ethics committees received and processed the applications variably, reflecting individual factors and local problems. To improve consensus and facilitate multicentre studies, standard forms and instructions are suggested and the establishment of a national committee or advisory group advocated. (shrink)

Objectives: To study the consent process experienced by participants who are enrolled in a molecular genetic research study that aims to find new genetic mutations responsible for an apparently inherited disorder.Design: Semi-structured interviews and analysis/description of main themes.Participants: 78 members of 52 families who had been recruited to a molecular genetic study.Results: People were well informed about the goals, risks and benefits of the genetic research study but could not remember the consent process. They had mostly been recruited to take (...) part by trusted clinicians or their relatives but had little memory of, or concern about signing consent forms. Families appeared to regard the research as a continuation of their, or their relatives’, clinical care.Conclusions: Ethical review should be more flexible in its attitude to consent forms and written information sheets for some sorts of research. For rare genetic disease studies where research has been discussed fully within the clinical setting then the consent obtained at that time could suffice rather than needing extra consent at a later stage. However, clinician-researchers will need to ensure that their duty of care extends for the duration of the research and beyond. (shrink)

Next SectionBackground: Publication bias and discrimination are increasingly recognised in medicine. A survey was conducted to determine if medical journals were more likely to publish research reports from members of their own than a rival journal’s editorial board. Methods: A retrospective review was conducted of all research reports published in 2006 in the four competing medical journals within five medical specialties. Only three journals were willing to divulge the authorship of reports that had been rejected. Results: Overall, 4460 research reports (...) were published in 2006 by the 20 journals from five subspecialties (mean 223 (SD = 164) reports per journal; median 176; interquartile range 108–238). On average, 17.2 (7.7%) reports were from a journal’s own editorial board (SD = 10.7; median 15; interquartile range 10–23; n = 20), and 6.3 (2.8%) reports were from a member of the editorial board of one of the three rival journals within the specialty (SD = 7.3; median 3.5; interquartile range 1–8; n = 60). There was a statistically significant excess of publications from the journal’s own editorial board in 14 of the 20 journals (p<0.05). Journals were almost three times more likely to publish reports from their own editorial board than from one of the three rivals within their subspecialty (p<0.0001; median difference 11; Mann–Whitney U test; power for 5% significance >99.99%). Conclusions: There was a significant excess of publications from medical journals’ own editorial boards, although it is not possible to determine whether this is due to bias in the peer review process or selective submission by editors. (shrink)

Husserlian reduction is a rigorous method for describing the foundations of psychiatric experience. With Jaspers we consider three main principles inspired by phenomenological reduction: direct givenness, absence of presuppositions, re-presentation. But with Binswanger alone we refer to eidetic and transcendental reduction: to establish a critical epistemology; to directly investigate the constitutive processes of mental phenomena and their disturbances, freed from their nosological background; to question the constitution of our own experience when facing a person with mental illness. Regarding the last (...) item, we suggest a specific kind of reduction, typically intersubjective from the start, which we call the ‘looking-glass reduction'. The schizophrenic experience -- understood as a ‘loss of taken-for-grantedness’ implying the constitutions of the body, of the other, and of internal time -- is a real ‘epochal provocation’ for the psychiatrist. As the horizon it opens seems to be both corporeal and narrative, this ‘provoking’ of an epoche in the attitude of the psychiatrist himself and the resistances it implies raise important issues regarding the general constitution of human experience. (shrink)

The interaction between cavity modes and optical transitions leads to new coupled light-matter states in which the energy is periodically exchanged between the matter states and the optical mode. Here we present experimental evidence of optical strong coupling between modes of individual sub-wavelength metamaterial nanocavities and engineered optical transitions in semiconductor heterostructures. We show that this behaviour is generic by extending the results from the mid-infrared to the near-infrared. Using mid-infrared structures, we demonstrate that the light-matter coupling occurs at the (...) single resonator level and with extremely small interaction volumes. We calculate a mode volume of 4.9 × 10 from which we infer that only ~2,400 electrons per resonator participate in this energy exchange process. (shrink)

Two decades of research on euthanasia in the Netherlands have resulted into clear insights in the frequency and characteristics of euthanasia and other medical end-of-life decisions in the Netherlands. These empirical studies have contributed to the quality of the public debate, and to the regulating and public control of euthanasia and physician-assisted suicide. No slippery slope seems to have occurred. Physicians seem to adhere to the criteria for due care in the large majority of cases. Further, it has been shown (...) that the majority of physicians think that the euthanasia Act has improved their legal certainty and contributes to the carefulness of life-terminating acts. In 2005, eighty percent of the euthanasia cases were reported to the review committees. Thus, the transparency envisaged by the Act still does not extend to all cases. Unreported cases almost all involve the use of opioids, and are not considered to be euthanasia by physicians. More education and debate is needed to disentangle in these situations which acts should be regarded as euthanasia and which should not. Medical end-of-life decision-making is a crucial part of end-of-life care. It should therefore be given continuous attention in health care policy and medical training. Systematic periodic research is crucial for enhancing our understanding of end-of-life care in modern medicine, in which the pursuit of a good quality of dying is nowadays widely recognized as an important goal, in addition to the traditional goals such as curing diseases and prolonging life. (shrink)

Recent policy in relation to clinical research proposals in the UK has distinguished between two types of review: scientific and ethical. This distinction has been formally enshrined in the recent changes to research ethics committee structure and operating procedures, introduced as the UK response to the EU Directive on clinical trials. Recent reviews and recommendations have confirmed the place of the distinction and the separate review processes. However, serious reservations can be mounted about the science/ethics distinction and the policy of (...) separate review that has been built upon it. We argue here that, first, the science/ethics distinction is incoherent, and, second, that RECs should not only be permitted to consider a study’s science, but that they have anobligation do so. (shrink)

In England, Wales and Scotland, the vast majority of abortions take place in the first trimester of pregnancy. In 2009, for example, 91% of abortions were carried out at under 13 weeks gestation for women resident in England and Wales. 1 Early abortion opens up the opportunity for a woman to have a medical abortion rather than a surgical abortion. Medical abortion is considered to be less invasive and less expensive than surgical abortion, and is increasingly becoming the preferred method. (...) 1 The proportion of medical abortions to surgical abortions has doubled in the last five years with 52% of abortions being medical abortions under 9 weeks gestation in 2009. A medical abortion typically involves taking mifepristone to block the hormones that help a pregnancy to continue, and then later on misoprostol, which makes the womb expel the embryo/fetus, usually within 4–6 h. Current legislation requires that both sets of drugs are administered in an NHS hospital or approved place, but women can go home after taking the second dose of drugs to complete the abortion. There has long been disagreement between the Department of Health and the British Pregnancy Advisory Services about what constitutes ‘any treatment for the termination of pregnancy’ under the Abortion Act 1967, specifically whether a woman taking the second set of drugs is considered to be undergoing the ‘treatment’ and is therefore required to be present in premises permitted under the Act. At the end of 2010, BPAS went to the High Court to challenge the Department of Health's view that the legislation requires women to take both sets of drugs in an approved place. BPAS argued that ‘treatment’ stops at the point of prescription and women should be able to go home, …. (shrink)