We consider a deterministic rewrite system for combinatory logic over combinators , and . Terms will be represented by graphs so that reduction of a duplicator will cause the duplicated expression to be "shared" rather than copied. To each normalizing term we assign a weighting which is the number of reduction steps necessary to reduce the expression to normal form. A lambda-expression may be represented by several distinct expressions in combinatory logic, and two combinatory logic expressions are considered equivalent if (...) they represent the same lambda-expression (up to --equivalence). The problem of minimizing the number of reduction steps over equivalent combinator expressions (i.e., the problem of finding the "fastest running" combinator representation for a specific lambda-expression) is proved to be NP-complete by reduction from the "Hitting Set" problem. (shrink)

Rights have two properties which prima facie appear to be inconsistent. The first is that they are conditional in the sense that one some occasions it is always justifiable for someone to act in a way which appears to be inconsistent with someone else's rights, such as when the defence of necessity applies. The second is that rights are indefeasible in the sense that they are not subject to being defeated our outweighed by utilitarian or policy considerations. If we view (...) rules and the rights which they establish as being subject to a ceteris paribus clause, the form of which generates out the exceptions, the conditionality of rights becomes reconcilable with their nondefeasibility. Such a view of rules and rights would entail that the goals of the law and their orderings be considered as a part of the law. When so viewed, propositions about goals and their orderings become legitimate premises for legal reasoning, furnishing solutions to hard cases in the law of torts, without resort to balancing of interests or judicial discretion. (shrink)

There is a growing recognition, stemming from work with both vertebrates and invertebrates, that the capacity for neuronal regeneration is critically dependent on the local microenvironment. That environment is largely created by the non‐neuronal elements of the nervous system, the neuroglia. Therefore an understanding of how glial cells respond to injury is crucial to understanding neuronal regeneration. Here we examine the process of repair in a relatively simple nervous system, that of the insect, in which it is possible to define (...) precisely the cellular events of the repair process. This repair is rapid and well organised; it involves the recruitment of blood cells, the division of endogenous glial elements and, possibly, migration from pre‐existing glial pools in adjacent ganglia. There are clear parallels between the events of repair and those of normal glial development. It seems likely that the ability of the insect central nervous system to repair resides in the retention of developmental capacities throughout its life and that damage results in the activation of this potential. (shrink)

The medium surrounding cells either in culture or in tissues contains a chemical mix varying with cell state. As solutes move in and out of the cytoplasmic compartment they set up characteristic signatures in the cellular boundary layers. These layers are complex physical and chemical environments the profiles of which reflect cell physiology and provide conduits for intercellular messaging. Here we review some of the most relevant characteristics of the extracellular/intercellular space. Our initial focus is primarily on cultured cells but (...) we extend our consideration to the far more complex environment of tissues, and discuss how chemical signatures in the boundary layer can or may affect cell function. Critical to the entire essay are the methods used, or being developed, to monitor chemical profiles in the boundary layers. We review recent developments in ultramicro electrochemical sensors and tailored optical reporters suitable for the task in hand. (shrink)

> Wealthy nations must do much more, much faster. The United Nations General Assembly in September 2021 will bring countries together at a critical time for marshalling collective action to tackle the global environmental crisis. They will meet again at the biodiversity summit in Kunming, China, and the climate conference 26) in Glasgow, UK. Ahead of these pivotal meetings, we—the editors of health journals worldwide—call for urgent action to keep average global temperature increases below 1.5°C, halt the destruction of nature (...) and protect health. Health is already being harmed by global temperature increases and the destruction of the natural world, a state of affairs health professionals have been bringing attention to for decades.1 The science is unequivocal; a global increase of 1.5°C above the preindustrial average and the continued loss of biodiversity risk catastrophic harm to health that will be impossible to reverse.2 3 Despite the world’s necessary preoccupation with COVID-19, we cannot wait for the pandemic to pass to rapidly reduce emissions. Reflecting the severity of the moment, this editorial appears in health journals across the world. We are united in recognising that only fundamental and equitable changes to societies will reverse our current trajectory. The risks to health of increases above 1.5°C are now well established.2 Indeed, no temperature rise is ‘safe’. In the past 20 years, heat-related mortality among people aged over 65 has increased by more than 50%.4 Higher temperatures have brought increased dehydration and renal function loss, dermatological malignancies, tropical infections, adverse mental health outcomes, pregnancy complications, allergies, and cardiovascular and pulmonary morbidity and mortality.5 6 Harms disproportionately affect the most vulnerable, including children, older populations, ethnic minorities, poorer communities and those with underlying health problems.2 4 Global heating is also contributing to the decline in …. (shrink)

Stem cell science is advancing at an unprecedented rate, with thousands of research papers being published every year and many clinical trials for a wide range of conditions underway as registered on ClinicalTrials.gov. This rapidly expanding and alluring field has brought with it ever more complex and multifaceted ethical issues, many of which require new guidelines, consent protocols and even change in legislation, since they do not fit comfortably in the existing bioethical regulations and protocols. Keeping up with the ethical (...) implications of stem cell research is daunting to the expert and non-expert. We review the various types of stem cells and then focus on multipotent and pluripotent cell types, since it is these cell types that bring with them the greatest research and therapeutic potential, while concurrently delivering novel ethical conundrums. Certain key considerations are currently lacking and what is needed is how to obtain permission from individuals who donate their biological material for both scientific inquiry and eventually, for their potential therapeutic utility. (shrink)

The Geological Society of London was the first learned society to be devoted solely to geology, and its members were responsible for much of the spectacular progress of the science in the nineteenth century. Its distinctive character as a centre of geological discussion and research was established within the first five years from its foundation in 1807. During this period its activities were directed, and its policies largely shaped, by its President, George Bellas Greenough, on whose unpublished papers this account (...) is chiefly based.The Society began as a small scientific dining club in London, but it developed rapidly into a learned society with a nation-wide membership. It became so independent in outlook and so active in research that it was felt to threaten the esteem of the Royal Society; and little more than a year after its foundation it clashed with the Royal Society so violently that its continued existence was for a time uncertain.Its development into a large independent society was the outcome of its ‘Baconian’ view of the importance of collecting geological facts as a surer basis for geological theories. For this purpose it initiated an ambitious scheme for co-operative research, which would unite the efforts of ‘philosophers’ with those of ‘practical men’. Only personal reasons seem to have kept the most prominent of the practical men—William Smith—from co-operating with the Society. (shrink)

The Protein Ontology (PRO; http://proconsortium.org) formally defines protein entities and explicitly represents their major forms and interrelations. Protein entities represented in PRO corresponding to single amino acid chains are categorized by level of specificity into family, gene, sequence and modification metaclasses, and there is a separate metaclass for protein complexes. All metaclasses also have organism-specific derivatives. PRO complements established sequence databases such as UniProtKB, and interoperates with other biomedical and biological ontologies such as the Gene Ontology (GO). PRO relates to (...) UniProtKB in that PRO’s organism-specific classes of proteins encoded by a specific gene correspond to entities documented in UniProtKB entries. PRO relates to the GO in that PRO’s representations of organism-specific protein complexes are subclasses of the organism-agnostic protein complex terms in the GO Cellular Component Ontology. The past few years have seen growth and changes to the PRO, as well as new points of access to the data and new applications of PRO in immunology and proteomics. Here we describe some of these developments. (shrink)

The handicap principle has come under significant challenge both from empirical studies and from theoretical work. As a result, a number of alternative explanations for honest signaling have been proposed. This paper compares the evolutionary plausibility of one such alternative, the "hybrid equilibrium," to the handicap principle. We utilize computer simulations to compare these two theories as they are instantiated in Maynard Smith's Sir Philip Sidney game. We conclude that, when both types of communication are possible, evolution is unlikely (...) to lead to handicap signaling and is far more likely to result in the partially honest signaling predicted by hybrid equilibrium theory. (shrink)

The Scottish Enlightenment provided the fledgling United States of America and its emerging universities with a philosophical orientation. For a hundred years or more, Scottish philosophers were both taught and emulated by professors at Princeton, Harvard and Yale, as well as newly founded colleges stretching from Rhode Island to Texas. This volume in the Library of Scottish Philosophy demonstrates the remarkable extent of this philosophical influence. Selections from William Smith, John Witherspoon, Samuel Stanhope Smith, Archibald Alexander, Alexander Campbell, (...) W.E. Channing, James McCosh, and C.S. Peirce, together with the editor's introductory and explanatory material, provide the modern reader with unprecedented access to this period of intellectual formation. (shrink)

South Africa shared with the world the warning of a new strain of SARS-CoV2, Omicron, in November 2021. As a result, many high-income countries (HICs) instituted complete travel bans on persons leaving South Africa and other neighbouring countries. These bans were unnecessary from a scientific standpoint, and they ran counter to the International Health Regulations. In short, South Africa was penalized for sharing data. Data sharing during pandemics is commonly justified by appeals to solidarity. In this paper, we argue that (...) solidarity is, at best, an aspirational ideal to work toward but that it cannot ground an obligation to share data. Instead, low-and-middle income countries (LIMCs) should be guided by the principle of reciprocity, which states that we ought to return good for good received. Reciprocity is necessarily a conditional principle. LMICs, we argue, should only share data during future pandemics on the condition that HICs provide enforceable assurances that the benefits of data sharing will be equitably distributed and that LMICs won’t be penalized for sharing information. (shrink)

This article examines the extent to which diversity characteristics and stakeholder role influence individuals’ corporate social orientation (CSO). Our findings indicate that one’s relationship to the organization as well as diversity, gender, and race influence one’s CSO. Specifically, we found that employees’ greatest concern was economic whereas customers had a stronger ethical orientation. The results also suggest that women as well as Black employees and customers place more emphasis on whether an organization is fulfilling its discretionary responsibilities than do males (...) and Whites. A model using the concept of value congruence is presented to guide future research. (shrink)

The unprecedented outbreak of Ebola virus disease in West Africa has raised several novel ethical issues for global outbreak preparedness. It has also illustrated that familiar ethical issues in infectious disease management endure despite considerable efforts to understand and mitigate such issues in the wake of past outbreaks. To improve future global outbreak preparedness and response, we must examine these shortcomings and reflect upon the current state of ethical preparedness. To this end, we focus our efforts in this article on (...) the examination of one substantial area: ethical guidance in pandemic plans. We argue that, due in part to their focus on considerations arising specifically in relation to pandemics of influenza origin, pandemic plans and their existing ethical guidance are ill-equipped to anticipate and facilitate the navigation of unique ethical challenges that may arise in other infectious disease pandemics. We proceed by outlining three reasons why this is so, and situate our analysis in the context of the EVD outbreak and the threat posed by drug-resistant tuberculosis: different infectious diseases have distinct characteristics that challenge anticipated or existing modes of pandemic prevention, preparedness, response, and recovery, clear, transparent, context-specific ethical reasoning and justification within current influenza pandemic plans are lacking, and current plans neglect the context of how other significant pandemics may manifest. We conclude the article with several options for reflecting upon and ultimately addressing ethical issues that may emerge with different infectious disease pandemics. (shrink)

Systems thinking has emerged as a means of conceptualizing and addressing complex public health problems, thereby challenging more commonplace understanding of problems and corresponding solutions as straightforward explanations of cause and effect. Systems thinking tries to address the complexity of problems through qualitative and quantitative modeling based on a variety of systems theories, each with their own assumptions and, more importantly, implicit and unexamined values. To date, however, there has been little engagement between systems scientists and those working in bioethics (...) and public health ethics. The goal of this paper is to begin to consider what it might mean to combine systems thinking with public health ethics to solve public health challenges. We argue that there is a role for ethics in systems thinking in public health as a means of elucidating implicit assumptions and facilitating ethics debate and dialogue with key stakeholders. (shrink)

Medical councils increasingly require graduates to understand law and to practise medicine mindful of the legal rules. In the UK a revised curriculum for medical law and ethics has been published. However, coverage of law in medical education remains variable and doubts exist about how far students acquire legal knowledge and skills in its implementation. This survey of students in two UK medical schools measured their law learning and their confidence in using this knowledge. Concept maps and a self-audit questionnaire (...) were used to capture students' understanding and perceptions of this knowledge domain and self-assessments of their legal knowledge and skills. A large sample was achieved across first, second and final year students. Students agree that a sound understanding of law is essential to being a good doctor. Their perceptions of law are generally positive but the interface between the legal rules and codes of medical ethics creates difficulty. In some areas students offer relatively confident self-assessments of their legal knowledge and skills for practising law. However, levels of confidence in other areas of their law learning raise doubts about the degree to which they can advocate for and protect their patients. Conclusions are drawn about the effectiveness of students' law learning and recommendations made for further research. (shrink)

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1 Evidence-based policy requires researchers to provide the answers to ecological questions that are of interest to policy makers. To find out what those questions are in the UK, representatives from 28 organizations involved in policy, together with scientists from 10 academic institutions, were asked to generate a list of questions from their organizations. 2 During a 2-day workshop the initial list of 1003 questions generated from consulting at least 654 policy makers and academics was used as a basis for (...) generating a short list of 100 questions of significant policy relevance. Short-listing was decided on the basis of the preferences of the representatives from the policy-led organizations. 3 The areas covered included most major issues of environmental concern in the UK, including agriculture, marine fisheries, climate change, ecosystem function and land management. 4 The most striking outcome was the preference for general questions rather than narrow ones. The reason is that policy is driven by broad issues rather than specific ones. In contrast, scientists are frequently best equipped to answer specific questions. This means that it may be necessary to extract the underpinning specific question before researchers can proceed. 5 Synthesis and applications. Greater communication between policy makers and scientists is required in order to ensure that applied ecologists are dealing with issues in a way that can feed into policy. It is particularly important that applied ecologists emphasize the generic value of their work wherever possible. (shrink)