NG van Kampen is a well-known theoretical physicist who has had a long and distinguished career. His research covers scattering theory, plasma physics, statistical mechanics, and various mathematical aspects of physics. In addition to his scientific work, he has written a number of papers about more general aspects of science. An indefatigable fighter for intellectual honesty and clarity, he has pointed out repeatedly that the fundamental ideas of physics have been needlessly obscured. As those papers appeared in various journals, (...) partly in Dutch, it was felt that it would be worthwhile to collect them (translating the Dutch material into English) and make them available to a larger audience. This is a book of major importance to scientists and university teachers. (shrink)

Theoretical determinism, as it is usually ascribed to Laplace, is neither verifiable nor falsifiable and has therefore no real content. It is not the same as predictability of actually observable phenomena. On the other hand, predictability is not an abstract principle; rather it is true to a certain degree, depending on the phenomena considered. It can be discussed only by examining the scientific state of affairs. This is done in some detail for classical statistical mechanics. Much of a recently published (...) debate on determinism is thereby obviated. (shrink)

Theoretical determinism, as it is usually ascribed to Laplace, is neither verifiable nor falsifiable and has therefore no real content. It is not the same as predictability of actually observable phenomena. On the other hand, predictability is not an abstract principle; rather it is true to a certain degree, depending on the phenomena considered. It can be discussed only by examining the scientific state of affairs. This is done in some detail for classical statistical mechanics. Much of a recently published (...) debate on determinism (Amsterdamski et al. 1990) is thereby obviated. (shrink)

Background Scientific and technological advancements in mapping and understanding the interrelated pathways through which biological and environmental exposures affect disease development create new possibilities for detecting disease risk factors. Early detection of such risk factors may help prevent disease onset or moderate the disease course, thereby decreasing associated disease burden, morbidity, and mortality. However, the ethical implications of screening for disease risk factors are unclear and the current literature provides a fragmented and case-by-case picture. Methods To identify key ethical considerations (...) arising from the early detection of disease risk factors, we performed a systematic scoping review. The Scopus, Embase, and Philosopher’s Index databases were searched for peer-reviewed, academic records, which were included if they were written in English or Dutch and concerned the ethics of (1) early detection of (2) disease risk factors for (3) disease caused by environmental factors or gene-environment interactions. All records were reviewed independently by at least two researchers. Results After screening 2034 titles and abstracts, and 112 full papers, 55 articles were included in the thematic synthesis of the results. We identified eight common ethical themes: (1) Reliability and uncertainty in early detection, (2) autonomy, (3) privacy, (4) beneficence and non-maleficence, (5) downstream burdens on others, (6) responsibility, (7) justice, and (8) medicalization and conceptual disruption. We identified several gaps in the literature, including a relative scarcity of research on ethical considerations associated with environmental preventive health interventions, a dearth of practical suggestions on how to address expressed concerns about overestimating health capacities, and a lack of insights into preventing undue attribution of health responsibility to individuals. Conclusions The ethical concerns arising with the early detection of risk factors are often interrelated and complex. Comprehensive ethical analyses are needed that are better embedded in normative frameworks and also assess and weigh the expected benefits of early risk factor detection. Such research is necessary for developing and implementing responsible and fair preventive health policies. (shrink)

Lysophosphatidic acid (LPA) is a lipid mediator with a wide variety of biological actions, particularly as an inducer of cell proliferation, migration and survival. LPA binds to specific G‐protein‐coupled receptors and thereby activates multiple signal transduction pathways, including those initiated by the small GTPases Ras, Rho, and Rac. LPA signaling has been implicated in such diverse processes as wound healing, brain development, vascular remodeling and tumor progression. Knowledge of precisely how and where LPA is produced has long proved elusive. Excitingly, (...) it has recently been discovered that LPA is generated from precursors by ‘autotaxin’, a once enigmatic exo‐phosphodiesterase implicated in tumor cell motility. Exogenous phospholipases D can also produce LPA, which may contribute to their toxicity. Here we review recent progress in our understanding of LPA bioactivity, signaling and synthesis. BioEssays 26:870–881, 2004. © 2004 Wiley Periodicals, Inc. (shrink)

It is a landmark theorem of McKinsey and Tarski that if we interpret modal diamond as closure, then \ is the logic of any dense-in-itself metrizable space. The McKinsey–Tarski Theorem relies heavily on a metric that gives rise to the topology. We give a new and more topological proof of the theorem, utilizing Bing’s Metrization Theorem.

Within ZFC, we develop a general technique to topologize trees that provides a uniform approach to topological completeness results in modal logic with respect to zero-dimensional Hausdorff spaces. Embeddings of these spaces into well-known extremally disconnected spaces then gives new completeness results for logics extending S4.2.

Although narcissists often emerge as leaders, the relationship between leader narcissism and follower performance is ambiguous and often even found to be negative. For women, narcissism seems especially likely to lead to negative evaluations. Since narcissists have the tendency to be impulsive and change their minds on a whim, they may come across as inconsistent. We propose “inconsistent leader behavior” as a new mechanism in the relationship between leader narcissism and follower performance and argue that leader gender plays an important (...) role in whether narcissistic leaders are perceived as inconsistent. Specifically, we expect leader narcissism to have a negative relationship with follower performance through perceived inconsistent leader behavior, especially for female leaders. Thus, we examine leader gender as a personal factor moderating the relationship between narcissism and perceived inconsistent behavior. Also, as perceived inconsistency is likely less problematic when a good relationship exists, we examine leader–member exchange as a contextual condition moderating the relationship between leader behavior and follower performance. We test our moderated mediation model in a multi-source study with 165 unique leader–follower dyads. As expected, leader narcissism was positively related to perceived inconsistent leader behavior, and this relationship was stronger for female leaders. Inconsistent leader behavior was negatively related to follower performance, but only when LMX was low. Our research highlights that perceived behavioral inconsistency can be problematic and—for female leaders—provides an explanation of the negative relation of leader narcissism with follower performance and of the inconsistencies in evaluations of narcissistic leaders’ effectiveness. (shrink)

Rapid developments in Artificial Intelligence are leading to an increasing human reliance on machine decision making. Even in collaborative efforts with Decision Support Systems (DSSs), where a human expert is expected to make the final decisions, it can be hard to keep the expert actively involved throughout the decision process. DSSs suggest their own solutions and thus invite passive decision making. To keep humans actively ‘on’ the decision-making loop and counter overreliance on machines, we propose a ‘reflection machine’ (RM). This (...) system asks users questions about their decision strategy and thereby prompts them to evaluate their own decisions critically. We discuss what forms RMs can take and present a proof-of-concept implementation of a RM that can produce feedback on users’ decisions in the medical and law domains. We show that the prototype requires very little domain knowledge to create reasonably intelligent critiquing questions. With this prototype, we demonstrate the technical feasibility to develop RMs and hope to pave the way for future research into their effectiveness and value. (shrink)

SummaryIntense, sustained nursing lengthens inter-birth intervals and is causally linked with low natural fertility. However, in traditional settings, the effects of such nursing on fertility are difficult to disentangle from those of nutrition. Results from an prospective, direct observational study of reproductive function in well-nourished Amele women who nurse intensively and persistently but who also have high fertility are here presented. Endocrine measures show that ovarian activity resumes by median 11·0 months postpartum. Median duration of postpartum amenorrhoea is 11·3 months, (...) time to next conception is 19·0 months, and the inter-birth interval is 28·0 months. Average life time fertility is 6·8. High fertility in Amele women is due both to refractoriness of reproductive function to suckling stimuli, and to maintenance of equivalent age-specific fertility rates across the reproductive life span. (shrink)

This article provides ethical guidance on using race in health research as a variable or in defining the study population. To this end, a plain, non-exhaustive checklist is provided for researchers and research ethics committees, preceded by a brief introduction on the need for justification when using race as a variable or in defining a study population, the problem of exoticism, that distinctions pertain between race, ethnicity and ancestry, the problematic naming of races, and that race does not serve well (...) as a presumed biological construct in genetic research. (shrink)

Church and theology on a mesoparadigmatic shift towards the third millennium This article is written from the assumption that the present-day shift from modernity to postmodernity, which influences both church and theology, might be described as mesoparadigmatic in nature. From a specific angle, postmodern theology is considered a contextualization of dialectical thinking and it should, therefore, not be understood as an absolute alternative to the previous paradigm, including reformational theology which anticipated the modem era in a particular sense. The aim (...) of the article is at focusing on postmodernity's selective departure from modernity by means of debating the opinions which have been held by the author and been responded to by others. The article is concluded with an illumination of the road the author is convinced ought to be taken by the church and in theology heading towards the third millennium, specifically against the background of the changing South African context. (shrink)

Peacemakers as children of God (Mt 5:9): A pragmatic-linguistic reading. The article investigates different options of the pragmatic meaning (implicature) of the beatitude in the Gospel of Matthew, ‘blessed are the peacemakers, for they shall be called children of God’ (Mt 5:9). It also explores this Jesus logion’s seemingly contradiction with Jesus’ remark in die Matthean mission discourse, ‘Do not think that I have come to bring peace on earth; I have not come to bring peace, but a sword’ (Mt (...) 10:34). The pragmatic use of the concept ‘peace’ in Matthew is probed against the background of scribal activity in the context of the restoration of villages in north-Galilee and south-Syria after the destruction of the temple in Jerusalem by the Romans. The pax Romana and Josephus’ appeal to the inhabitants of these villages to collaborate with the Romans is described as the context of these Matthean Jesus-logia. It argues that Matthew interprets Jesus as a ‘Mosaic Joshua’ in continuum with the Judaic tradition of Solomon as the ‘king of peace’, especially 1 Chronicles 22:5-11. The macarism about the ‘peacemakers as children of God’ is interpreted in correlation with the macarism ‘blessed are those who mourn, for they shall be comforted’ (Mt 5:4). The article concludes with the finding that the sword-motif in Matthew 10:4 does not contradict the beatitude on peace in Matthew 5:9. (shrink)

Metaphors for the encounter between God and humanity and a roaming theologian’s reflective journey. This article maps the theology of Christo van der Merwe as a mobilising theology which aided the Netherdutch Reformed Church in Africa in discerning its character, role and purpose. The core of Van der Merwe’s theology consists of a journey with God as encountered in the narratives about Jesus and the Spirit told in the Christian Bible. The article shows that the mobilising core of his theology (...) is due to an ‘interoperational relationship’ between ‘knowing and believing’. In the article, the metaphor ‘roaming’ is used to illustrate this biographical journey as contextual theology which equips pastors with ministerial skills to take care of people who are haunted by trauma. (shrink)