1,434 research outputs found

    Explaining cooperative groups via social niche construction

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    Cooperative behaviours can be defined as those that benefit others at an apparent cost to self. How these kinds of behaviours evolve has been a topic of great interest in evolutionary biology, as the Darwinian paradigm seems to suggest that nature will be “red in tooth and claw” and that we would not expect one organism to evolve to help another. The evolution-of-cooperation literature has therefore generally been about showing how the altruism involved in these cases is only apparent (see Bergstrom 2002 for an excellent review). Consider kin selection, in which interactions are more likely to occur between related individuals. The cost of altruism to the individual is real but, having identified the correct score-keeping level as the genetic one, it turns out that the cooperative act is not costly but profitable. More generally, successful explanations for cooperation rely on the presence of a population structure that clusters cooperators together, such that they enjoy the benefits of each others' actions. However, the question that has been left largely unaddressed is how does this structure itself evolve? If we want to really explain why organisms cooperate, then we need to explain not just their adaptation to their social environment, but how they came to live in that environment. Recent work by Powers (2010) and Powers et al. (in press) has addressed this question. They show that social behaviour can exert indirect selection pressure on population structure-modifying traits, causing individuals to adaptively modify their population structure to support greater cooperation. Moreover, they argue that any component of selection on structure-modifying traits that is due to social behaviour must be in the direction of increased cooperation; that component of selection cannot be in favour of the conditions for greater selfishness. Powers et al. then examine the conditions under which this component of selection on population structure exists. They argue that not only can population structure drive the evolution of cooperation, as in classical models, but that the benefits of greater cooperation can in turn drive the evolution of population structure: a positive feedback process that they refer to as social niche construction (after Odling-Smee et al. 2003). Maynard Smith and Szathmary (1995) note that most of the big unanswered questions in biology are not about how a particular behaviour is selected for at one level of organization but about the emergence of whole new levels of organization, e.g., the transition from single- to multi-celled organisms, or from solitary insects to eusocial colonies. Any satisfactory account of these transitions must explain how the individuals came to live in a population structure that supported high degrees of cooperation, as well as showing that cooperation is individually advantageous given that structure. The social niche construction process identified by Powers et al. can explain some of the major transitions, by showing how a new selective level can begin through evolution of individual characters, such as group size preference or dispersal tendency. The potential emergence of reliable cooperation via the co-evolution of individual cooperative and population-structuring behaviours demonstrates that groups of cooperating agents can create an environment in which they become so “locked in” to their group identity that the group warrants redescription as an individual in its own right. Consider the move from independent protozoans, to an intermediate cooperative stage as in slime moulds, to fully multi-cellular animals. Such creation of population structures that support cooperation parallels negotiation of a social contract. What are the philosophical implications of this perspective for understanding and explaining human social behaviour? On the one hand, it gives respectability and unique explanatory value to group-selectionist accounts. Explaining the origin of within-group cooperation and the origin of the groups themselves become part of the same project, which in turn means that we cannot understand social and cooperative behaviour in humans without understanding human population-structuring traits, e.g., living in family groups, group fission-fusion behaviours, migratory behaviours, etc. What will the explanations we seek look like? de Pinedo and Noble (2008) have argued that the description of evolved behaviour cannot be exclusively in mechanistic terms: we need both explanations that focus on an agent’s interaction with its environment, and explanations that focus on the physical or computational enabling conditions of such an interaction. In a context in which what counts as an agent is taken for granted, de Pinedo and Noble argue that both agent and sub-agent level explanations will be required. The perspective being outlined here forces an expansion of that position and reminds us that agency is not to be taken for granted; that it emerges from a lower level of organization after a history of selection brings simpler entities together in a coherent cooperative whole. The implication is that truly multi-level explanations will be necessary in the area of social behaviour. We explain the origin of the multi-cellular organism as the result of a cooperative merger of single-celled organisms, and we explain the origin of a super-organism such as an ant colony in a similar way. At each transition, the autonomous agents of the previous level become component mechanisms in the next, but no explanatory level can be entirely done away with. A human being is an example of a multi-cellular organism with a highly developed social aspect, occupying an intermediate point between radical individual independence and total group cohesion. To fully explain human behaviour, we need to know about the cellular machinery that enables personal-level agency. But we also need to know how human machinery fits together into families, communities and nations that will, at least partially, have their own emergent goals and purposes: “partially” because we are not yet a super-organism, of course. In conclusion, the perspective we outline suggests a view of the social contract as not at all unique to Hobbesian rational agents who have become tired of an insecure and violent lifestyle. Instead the ongoing negotiation of the social contract amongst ourselves can be seen as echoing earlier, now-successfully-concluded negotiations between the entities that became our genes and then our cells

    Patient relevant bleeding complications; it's bleeding complicated

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    Antithrombotic therapy in palliative care

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    Management of venous thromboembolism (VTE) in patients in advanced cancer can be difficult due to the increased risk of recurrent and extending VTE despite therapeutic anticoagulation, and of bleeding due to or exacerbated by anticoagulation. Currently, best practice is long term administration of low molecular weight heparin (LMWH), but a recurrent VTE and bleeding rate remains, and some patients have contra-indications to anticoagulation. Newer anticoagulants such as oral anti-thrombin agents and biotinylated idrapurinux may have a role in the future.Management of venous thromboembolism (VTE) in patients in advanced cancer can be difficult due to the increased risk of recurrent and extending VTE despite therapeutic anticoagulation, and of bleeding due to or exacerbated by anticoagulation. Currently, best practice is long term administration of low molecular weight heparin (LMWH), but a recurrent VTE and bleeding rate remains, and some patients have contra-indications to anticoagulation. Newer anticoagulants such as oral anti-thrombin agents and biotinylated idrapurinux may have a role in the future

    Hydrochemical determination of source water contributions to Lake Lungo and Lake Ripasottile (central Italy)

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    Lake Lungo and Lake Ripasottile are two shallow (4-5 m) lakes located in the Rieti Basin, central Italy, that have been described previously as surface outcroppings of the groundwater table. In this work, the two lakes as well as springs and rivers that represent their potential source waters are characterized physio-chemically and isotopically, using a combination of environmental tracers. Temperature and pH were measured and water samples were analyzed for alkalinity, major ion concentration, and stable isotope (δ2H, δ18O, δ13C of dissolved inorganic carbon, and δ34S and δ18O of sulfate) composition. Chemical data were also investigated in terms of local meteorological data (air temperature, precipitation) to determine the sensitivity of lake parameters to changes in the surrounding environment. Groundwater represented by samples taken from Santa Susanna Spring was shown to be distinct with SO4 2- and Mg2+ content of 270 and 29 mg/L, respectively, and heavy sulfate isotopic composition (δ34S=15.2‰ and δ18O=10‰). Outflow from the Santa Susanna Spring enters Lake Ripasottile via a canal and both spring and lake water exhibits the same chemical distinctions and comparatively low seasonal variability. Major ion concentrations in Lake Lungo are similar to the Vicenna Riara Spring and are interpreted to represent the groundwater locally recharged within the plain. The δ13CDIC exhibit the same groupings as the other chemical parameters, providing supporting evidence of the source relationships. Lake Lungo exhibited exceptional ranges of δ13CDIC (±5‰) and δ2H, δ18O (±5 ‰ and ±7 ‰, respectively), attributed to sensitivity to seasonal changes. The hydrochemistry results, particularly major ion data, highlight how the two lakes, though geographically and morphologically similar, represent distinct hydrochemical facies. These data also show a different response in each lake to temperature and precipitation patterns in the basin that may be attributed to lake water retention time. The sensitivity of each lake to meteorological patterns can be used to understand the potential effects from long-term climate variability

    The challenge pathway: a mixed methods evaluation of an innovative care model for the palliative and end-of-life care of people with dementia (innovative practice)

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    An innovative service for the palliative and end-of-life care of people with dementia was introduced at a UK hospice. This evaluation involved analysis of audit data, semi-structured interviews with project staff (n=3) and surveys of family carers (n=15) and professionals (n=20). The service has increased access to palliative, end-of-life care and other services. Improvements were reported in the knowledge, confidence and care skills of family carers and professionals. Carers felt better supported and it was perceived that the service enabled more patients to be cared for at home or in their usual place of care

    COVID-19 confessions: a qualitative exploration of healthcare workers experiences of working with COVID-19

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    Objectives To gain insight into the experiences and concerns of front-line National Health Service (NHS) workers while caring for patients with COVID-19. Design Qualitative analysis of data collected through an anonymous website (www.covidconfidential) provided a repository of uncensored COVID-19 experiences of front-line NHS workers, accessed via a link advertised on the Twitter feed of two high profile medical tweeters and their retweets. Setting Community of NHS workers who accessed this social media. Participants 54 healthcare workers, including doctors, nurses and physiotherapists, accessed the website and left a ‘story’. Results Stories ranged from 1 word to 10 min in length. Thematic analysis identified common themes, with a central aspect being the experience and psychological consequence of trauma. Specific themes were: (1) the shock of the virus, (2) staff sacrifice and dedication, (3) collateral damage ranging from personal health concerns to the long-term impact on, and care of, discharged patients and (4) a hierarchy of power and inequality within the healthcare system. Conclusions COVID-19 confidential gave an outlet for unprompted and uncensored stories of healthcare workers in the context of COVID-19. In addition to personal experiences of trauma, there were perceptions that many operational difficulties stemmed from inequalities of power between management and front-line workers. Learning from these experiences will reduce staff distress and improve patient care in the face of further waves of the pandemic

    Resistivity-driven State Changes in Vertically Stratified Accretion Disks

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    We investigate the effect of shear viscosity and Ohmic resistivity on the magnetorotational instability (MRI) in vertically stratified accretion disks through a series of local simulations with the Athena code. First, we use a series of unstratified simulations to calibrate physical dissipation as a function of resolution and background field strength; the effect of the magnetic Prandtl number, Pm = viscosity/resistivity, on the turbulence is captured by ~32 grid zones per disk scale height, H. In agreement with previous results, our stratified disk calculations are characterized by a subthermal, predominately toroidal magnetic field that produces MRI-driven turbulence for |z| < 2 H. Above |z| = 2 H, magnetic pressure dominates and the field is buoyantly unstable. Large scale radial and toroidal fields are also generated near the mid-plane and subsequently rise through the disk. The polarity of this mean field switches on a roughly 10 orbit period in a process that is well-modeled by an alpha-omega dynamo. Turbulent stress increases with Pm but with a shallower dependence compared to unstratified simulations. For sufficiently large resistivity, on the order of cs H/1000, where cs is the sound speed, MRI turbulence within 2 H of the mid-plane undergoes periods of resistive decay followed by regrowth. This regrowth is caused by amplification of toroidal field via the dynamo. This process results in large amplitude variability in the stress on 10 to 100 orbital timescales, which may have relevance for partially ionized disks that are observed to have high and low accretion states.Comment: very minor changes, accepted to Ap

    Managing, making sense of and finding meaning in advanced illness: a qualitative exploration of the coping and wellbeing experiences of patients with lung cancer

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    Coping plays an essential role in maintaining the wellbeing of patients with cancer. A number of different coping responses and strategies have been identified in the literature. The value and relevance of meaning based coping theory has also been emphasised, including Antonovosky’s (1979) Sense of Coherence (SoC) theory. Ten patients with advanced lung cancer were interviewed up to three times. A total of twenty in depth interviews were carried out, fully transcribed and data were analysed following a methodology of Interpretative Phenomenological Analysis. Three broad domains were identified to categorise the core life concerns of participants; making sense of and managing one’s illness; maintaining daily life and relationships and confronting the future. Within these domains multiple coping themes are identified, which to varying degrees help to maintain patient wellbeing and quality of life. This paper considers the relevance of SoC theory for understanding the coping experiences of patients with advanced cancer, and identifies resources and factors likely to support patient coping, with implications for health and social care services
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