We introduce the horizontal and vertical topologies on the product of topological spaces, and study their relationship with the standard product topology. We show that the modal logic of products of topological spaces with horizontal and vertical topologies is the fusion ${\bf S4}\oplus {\bf S4}$ . We axiomatize the modal logic of products of spaces with horizontal, vertical, and standard product topologies. We prove that both of these logics are complete for the product of rational numbers ${\Bbb Q}\times {\Bbb Q}$ (...) with the appropriate topologies. (shrink)

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)

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)

Perforation or gap formation in a vegetation is a major process in landscape transformation. The occurrence of gaps profoundly alters the microclimatical conditions in a vegetation. A method is proposed to quantify perforation by using the three main 2-D characteristics of the gaps: area, number and boundary length. New measures are developed by normalizing the observed values to the reference status of minimum and maximum perforation. As minimum perforation status, the presence of one single gap with area equal to the (...) map resolution is assumed. The new measures are combined using a 3-D Euclidean distance to visualize the process and to detect changes. The method is exemplified using a field case of gaps in a tropical terra firme rainforest at Tiputini, Ecuador. (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)

The missionary work of the Nederduitsch Hervormde Kerk van Afrika in theory and practice: in the past, present and futureIn this article a short survey is given of the missionary work, both in theory and practice, of the Nederduitsch Hervormde Kerk during the last fifty years. There is also an indication that the Church has reached a crucial point which is going to require thorough rethinking and reconsideration of our missionary work.

Introduction: The Dutch Euthanasia Act states that euthanasia is not punishable if the attending physician acts in accordance with the statutory due care criteria. These criteria hold that: there should be a voluntary and well-considered request, the patient’s suffering should be unbearable and hopeless, the patient should be informed about their situation, there are no reasonable alternatives, an independent physician should be consulted, and the method should be medically and technically appropriate. This study investigates whether physicians experience problems with these (...) criteria in medical practice.Methods: In 2006, questionnaires were sent to a random, stratified sample of 2100 Dutch physicians . Physicians were asked about problems in their decision-making related to requests for euthanasia or assisted suicide after enforcement of the 2002 Euthanasia Act.Results: Of all physicians who had received a request for euthanasia or assisted suicide , 25% had experienced problems in the decision-making with regard to at least one of the criteria of due care. Physicians who had experienced problems mostly indicated to have had problems related to evaluating whether or not the patient’s suffering was unbearable and hopeless and whether or not the patient’s request was voluntary or well considered .Discussion: Physicians in The Netherlands most frequently reported problems related to aspects in which they have to evaluate the patient’s subjective perspective. However, it can be questioned whether placing emphasis on these subjective aspects is an adequate fulfilment of the duties imposed on physicians, as laid down in the Dutch Euthanasia Act. (shrink)

This article addresses the ability of Parallel Distributed Processing (PDP) networks to generate stagewise cognitive development in accordance with Piaget's theory of cognitive epigenesis. We carried out a replication study of the simulation experiments by McClelland (1989) and McClelland and Jenkins (1991) in which a PDP network learns to solve balance scale problems. In objective tests motivated from catastrophe theory, a mathematical theory of transitions in epigenetical systems, no evidence for stage transitions in network performance was found. It is concluded (...) that PDP networks lack the ability to recover the positive outcomes of analogous catastrophe analyses of real cognitive developmental data. In an attempt to further characterize the learning behaviour of PDP networks, we carried out a second simulation study using the discrimination‐shift paradigm. The results thus obtained indicate that PDP learning is compatible with the learning of stimulus‐response relationships, not with the acquisition of mediating rules such as conceived in (neo‐)Piagetian theory. In closing, we speculate about the feasibility of simulating stagewise development with alternative network architectures. (shrink)

We apply an online optimization process based on machine learning to the production of Bose-Einstein condensates. BEC is typically created with an exponential evaporation ramp that is optimal for ergodic dynamics with two-body s-wave interactions and no other loss rates, but likely sub-optimal for real experiments. Through repeated machine-controlled scientific experimentation and observations our ’learner’ discovers an optimal evaporation ramp for BEC production. In contrast to previous work, our learner uses a Gaussian process to develop a statistical model of the (...) relationship between the parameters it controls and the quality of the BEC produced. We demonstrate that the Gaussian process machine learner is able to discover a ramp that produces high quality BECs in 10 times fewer iterations than a previously used online optimization technique. Furthermore, we show the internal model developed can be used to determine which parameters are essential in BEC creation and which are unimportant, providing insight into the optimization process of the system. (shrink)