A theory for investment across defences triggered at different stages of a predator-prey encounter

We introduce a general theoretical description of a combination of defences acting sequentially at different stages in the predatory sequence in order to make predictions about how animal prey should best allocate investment across different defensive stages. We predict that defensive investment will often be concentrated at stages early in the interaction between a predator individual and the prey (especially if investment is concentrated in only one defence, then it will be in the first defence). Key to making this prediction is the assumption that there is a cost to a prey when it has a defence tested by an enemy, for example because this incurs costs of deployment or tested costs as a defence is exposed to the enemies; and the assumption that the investment functions are the same among defences. But if investment functions are different across defences (e.g. the investment efficiency in making resources into defences is higher in later defences than in earlier defences), then the contrary could happen. The framework we propose can be applied to other victim-exploiter systems, such as insect herbivores feeding on plant tissues. This leads us to propose a novel explanation for the observation that herbivory damage is often not well explained by variation in concentrations of toxic plant secondary metabolites. We compare our general theoretical structure with related examples in the literature, and conclude that coevolutionary approaches will be profitable in future work

Decompressive Laminectomy in the Management of Spinal Epidural Metastases

In a series of 60 patients undergoing decompression laminectomy for metastatic malignancy, the median survival was 3.3 months with 11 patients (18%) living for at least one year and ambulating during part of this survival period. Forty-three per cent of the group were able to ambulate for at least some period postoperatively. If a patient could ambulate preoperatively he had a two-thirds chance of ambulating afterwards; conversely, if he could not ambulate preoperatively. he had a two-thirds chance of not ambulating postoperatively. The lymphoma group had the best prognosis. Long lesions and highly vascular tumors fared poorly. Paralysis (as defined by inability to ambulate) had developed with great rapidity in half of the patients unable to walk prior to operation. We postulate that this was caused by infarction of the spinal cord. A plea is made for early diagnosis and effective removal of these lesions before signs of cord compression are evident, and especially before the patient loses his ability to walk

Tele-operated high speed anthropomorphic dextrous hands with object shape and texture identification

This paper reports on the development of two number of robotic hands have been developed which focus on tele-operated high speed anthropomorphic dextrous robotic hands. The aim of developing these hands was to achieve a system that seamlessly interfaced between humans and robots. To provide sensory feedback, to a remote operator tactile sensors were developed to be mounted on the robotic hands. Two systems were developed, the first, being a skin sensor capable of shape reconstruction placed on the palm of the hand to feed back the shape of objects grasped and the second is a highly sensitive tactile array for surface texture identification

Maximum Likelihood Estimation in Gaussian Chain Graph Models under the Alternative Markov Property

The AMP Markov property is a recently proposed alternative Markov property for chain graphs. In the case of continuous variables with a joint multivariate Gaussian distribution, it is the AMP rather than the earlier introduced LWF Markov property that is coherent with data-generation by natural block-recursive regressions. In this paper, we show that maximum likelihood estimates in Gaussian AMP chain graph models can be obtained by combining generalized least squares and iterative proportional fitting to an iterative algorithm. In an appendix, we give useful convergence results for iterative partial maximization algorithms that apply in particular to the described algorithm.Comment: 15 pages, article will appear in Scandinavian Journal of Statistic

Souvenirs, salvage and storied things: remembering community

What I am talking about comes from a much larger set of projects with a number of collaborators so I will be ventriloquising along the way today. What effect does it have if we take that supply chain and value chain and take it even further, into the after life of things. And I am thinking about the Tales of Things of Electronic Memory. Lets extend the social biographies. Lets look at the movement in and out of the commodity phase. Not just ending as commodities and having use-value, but becoming commodities again then stopping being commodities again and so on. So this is a story that is also about circulation from stocks of objects. Things that we hold idling in our house, our wardrobes and things which are held in hiding by the state that we will come on to and many things that are circulated and how they made to circulate. A large part of the story is about things and about changing things in order to rekindle value. How do you take something which has no value let in it, no worth if you want to put it in those terms, and rekindle that, recreate worth from it? So this is dealing with consumption, not just consumption in terms of using, as context as Irene would says, but also as using up, consuming in that sense, finishing it. So I want to tell some stories about remainder objects; the things which are left over, or actually remainders of objects. What happens when the object themselves have got used up during consumption? And find their story map of object destruction, about actually using things until they have gone, until they have broken. So to continue that cheery theme of death and destruction, I thought I would just illustrate this in a few quotes in terms of things and objects. I will start with Robert Smithson’s take on this. The conceptual artist of the 1960s and 70s in the United States, with his comments: ‘separate forms, objects, shapes are mere convenient fictions. There is only an uncertain disintegrating order that transcends the limits of rational separations.” Now he does not acknowledge it, but basically he lifted that from Henri Bergson, who was summarsied by Bertrand Russell as being about being as flow: “separate things, beginnings and endings are mere convenient fictions: imaginary congealings of the stream” and of course we can take this back further to Heraclitus or Lucretius or if we want back to someone like Gautama Buddha's final words: “It came as if in all composite things, everything ends up breaking, everything ends up being destroyed.

Education Can Compensate for Society - a Bit

In this paper I reflect on the findings of a number of loosely related research projects undertaken with colleagues over the last ten years. Their common theme is equity, in formal education and beyond, in wider family and social settings, and with inequity expressed as the stratification of a variety of educational outcomes. The projects are based on a standard mixture of pre-existing records, official documents, large-scale surveys, observations, interviews and focus groups. The numeric data were largely used to create biographical models of educational experiences, and the in-depth data were used to try to explain individual decisions and disparities at each stage of the model. Data have been collected for England and Wales, in five other countries of the European Union and for Japan. A meta-view of these various findings suggests that national school intakes tend to be at least moderately segregated by prior attainment and socio-economic factors, and that learning outcomes as assessed by formal means, such as examinations, are heavily stratified by these same factors. There is no convincing evidence that compulsory schooling does very much to overcome the initial disparity in the resources and attainment of school intakes. On the other hand, there are indications that the nature of a national school system and the social experiences of young people in schools can begin to equalise educational outcomes as more widely envisaged, including learning to trust and willingness to help others, aspirations, and attitudes to continuing in education and training. The cost-free implications of the argument in this paper, if accepted, are that everything possible should be done to make school intakes comprehensive, and that explicit consideration, by teachers and leaders, of the applied principles of equity could reduce potentially harmful misunderstandings in educational contexts

The inclusion of delirium in version 2 of the National Early Warning Score will substantially increase the alerts for escalating levels of care: findings from a retrospective database study of emergency medical admissions in two hospitals

YesBackground The National Early Warning Score (NEWS) is being replaced with NEWS2 which adds 3 points for new confusion or delirium. We estimated the impact of adding delirium on the number of medium/high level alerts that are triggers to escalate care. Methods Analysis of emergency medical admissions in two acute hospitals (York Hospital (YH) and Northern Lincolnshire and Goole NHS Foundation Trust hospitals (NH)) in England. Twenty per cent were randomly assigned to have delirium. Results The number of emergency admissions (YH: 35584; NH: 35795), mortality (YH: 5.7%; NH: 5.5%), index NEWS (YH: 2.5; NH: 2.1) and numbers of NEWS recorded (YH: 879193; NH: 884072) were similar in each hospital. The mean number of patients with medium level alerts per day increased from 55.3 (NEWS) to 69.5 (NEWS2), a 25.7% increase in YH and 64.1 (NEWS) to 77.4 (NEWS2), a 20.7% increase in NH. The mean number of patients with high level alerts per day increased from 27.3 (NEWS) to 34.4 (NEWS2), a 26.0% increase in YH and 29.9 (NEWS) to 37.7 (NEWS2), a 26.1% increase in NH. Conclusions The addition of delirium in NEWS2 will have a substantial increase in medium and high level alerts in hospitalised emergency medical patients. Rigorous evaluation of NEWS2 is required before widespread implementation because the extent to which staff can cope with this increase without adverse consequences remains unknown

Turning psychology into policy: a case of square pegs and round holes?

This paper problematizes the ways in which the policy process is conceived in published psychological research. It argues that these conceptions of the policy process fail to ade- quately reflect the real-world dynamism and complexity of the processes and practices of social policy-making and implementation. In this context, psychological evidence needs to be seen as one type of evidence (amongst many others). In turn this requires researchers to take account of broader political processes that favour certain types of knowledge and disparage others. Rather than be regarded as objective and scientific, policy in this characterisation is regarded as a motivated form of politics. This multi-layered, multi-level hybrid structure is not immediately amenable to the well-intentioned interventions of psychologists. While the tendency of many psychologists is to overestimate the impact that we can have upon policy formation and implementation, there are examples where psychological theory and research has fed directly into UK policy developments in recent years. This paper draws on the recent Improving Access to Psychological Therapies (IAPT) initiative and the work of personality researcher Adam Perkins on the UK’s social security system to ask whether psychology has a sufficiently elaborated sense of its own evidence base to legitimately seek to influence key national areas of public policy. The article cautions against dramatic changes to policy pre- dicated upon any one reading of the variegated and, at times, contradictory psychological evidence base. It concludes that, in order to meaningfully contribute to the policy develop- ment process in a way which increases equality and social justice, psychologists need to be more strategic in thinking about how their research is likely to be represented and mis- represented in any particular context. Finally some possible directions for psychologists to take for a more meaningful relationship with policy are suggested

Spatial modulation of dark versus bright stimulus responses in the mouse visual system

A fundamental task of the visual system is to respond to both increases and decreases of luminance with action potentials (ON and OFF responses1–4). OFF responses are stronger, faster, and more salient than ON responses in primary visual cortex (V1) of both cats5,6 and primates,7,8 but in ferrets9 and mice,10 ON responses can be stronger, weaker,11 or balanced12 in comparison to OFF responses. These discrepancies could arise from differences in species, experimental techniques, or stimulus properties, particularly retinotopic location in the visual field, as has been speculated;9 however, the role of retinotopy for ON/OFF dominance has not been systematically tested across multiple scales of neural activity within species. Here, we measured OFF versus ON responses across large portions of visual space with silicon probe and whole-cell patch-clamp recordings in mouse V1 and lateral geniculate nucleus (LGN). We found that OFF responses dominated in the central visual field, whereas ON and OFF responses were more balanced in the periphery. These findings were consistent across local field potential (LFP), spikes, and subthreshold membrane potential in V1, and were aligned with spatial biases in ON and OFF responses in LGN. Our findings reveal that retinotopy may provide a common organizing principle for spatial modulation of OFF versus ON processing in mammalian visual systems