878 research outputs found

    The value of migration information for conservation prioritization of sea turtles in the Mediterranean

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    Aim: Conservation plans often struggle to account for connectivity in spatial prioritization approaches for the protection of migratory species. Protection of such species is challenging because their movements may be uncertain and variable, span vast distances, cross international borders and traverse land and sea habitats. Often we are faced with small samples of information from various sources and the collection of additional data can be costly and time-consuming. Therefore it is important to evaluate what degree of spatial information provides sufficient results for directing management actions. Here we develop and evaluate an approach that incorporates habitat and movement information to advance the conservation of migratory species. We test our approach using information on threatened loggerhead sea turtles (Caretta caretta) in the Mediterranean. Location: The Mediterranean Sea. Methods: We use Marxan, a spatially explicit decision support tool, to select priority conservation areas. Four approaches with increasing amounts of information about the loggerhead sea turtle are compared, ranging from (1) the broad distribution, (2) multiple habitat types that represent foraging, nesting and inter-nesting habitats, (3) mark-recapture movement information to (4) telemetry-derived migration tracks. Results: We find that spatial priorities for sea turtle conservation are sensitive to the information used in the prioritization process. Setting conservation targets for migration tracks altered the location of conservation priorities, indicating that conservation plans designed without such data would miss important sea turtle habitat. We discover that even a small number of tracks make a significant contribution to a spatial conservation plan if those tracks are substantially different. Main conclusions: This study presents a novel approach to improving spatial prioritization for conserving migratory species. We propose that future telemetry studies tailor their efforts towards conservation prioritization needs, meaning that spatially dispersed samples rather than just large numbers should be obtained. This work highlights the valuable information that telemetry research contributes to the conservation of migratory species

    Sequential Equilibria and Cheap Talk in Infinite Signaling Games. Part 1: Sequential Equilibria

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    An example shows that there are well-behaved infinte signaling games with no sequential equilibria. We explore the relationship between equilibrium outcomes of the infinite game and those of approximating games. Consider a sequence of signaling games approaching a limit game. A "(sub)sequence of equilibrium outcomes of the approximating games will converge to a limit distribution. That limit distribution will be an equilibrium outcome of the limit game if it can be realized by strategies of the limit game. As a result of this general convergence result, we prove the existance of sequential and weak-best-response equilibria for strongly monotonic games. In a companion article we explore the role of cheap talk in solving the non-existence problem.

    The relationship between transformational leadership and follower sickness absence:The role of presenteeism

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    The impact of transformational leaders on employee health and well-being has received much attention. Less research has focused on the relationships between transformational leaders and followers’ sickness absenteeism. In the present study, we examined the relationships between presenteeism, group-level transformational leadership, and sickness absence rates in a three-year longitudinal study in a postal service (N = 155). We found group-level transformational leadership in year 1 predicted sickness absenteeism in year 2, but not year 3. In examining conditions under which transformational leadership may be linked to higher levels of sickness absenteeism, we found that presenteeism in year 1 moderated the link between transformational leadership in year 1 and sickness absenteeism in year 3, such that followers working in groups with a transformational leader and who were high in presenteeism reported higher levels of sickness absenteeism. Our results suggest a complex picture of the relationship between transformational leadership and sickness absenteeism, transformational leaders may promote self-sacrifice of vulnerable followers by encouraging them to ignore their illnesses leading to increased risks of sickness absence in the long-term

    AltitudeOmics: The Integrative Physiology of Human Acclimatization to Hypobaric Hypoxia and Its Retention upon Reascent.

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    An understanding of human responses to hypoxia is important for the health of millions of people worldwide who visit, live, or work in the hypoxic environment encountered at high altitudes. In spite of dozens of studies over the last 100 years, the basic mechanisms controlling acclimatization to hypoxia remain largely unknown. The AltitudeOmics project aimed to bridge this gap. Our goals were 1) to describe a phenotype for successful acclimatization and assess its retention and 2) use these findings as a foundation for companion mechanistic studies. Our approach was to characterize acclimatization by measuring changes in arterial oxygenation and hemoglobin concentration [Hb], acute mountain sickness (AMS), cognitive function, and exercise performance in 21 subjects as they acclimatized to 5260 m over 16 days. We then focused on the retention of acclimatization by having subjects reascend to 5260 m after either 7 (n = 14) or 21 (n = 7) days at 1525 m. At 16 days at 5260 m we observed: 1) increases in arterial oxygenation and [Hb] (compared to acute hypoxia: PaO2 rose 9±4 mmHg to 45±4 while PaCO2 dropped a further 6±3 mmHg to 21±3, and [Hb] rose 1.8±0.7 g/dL to 16±2 g/dL; 2) no AMS; 3) improved cognitive function; and 4) improved exercise performance by 8±8% (all changes p<0.01). Upon reascent, we observed retention of arterial oxygenation but not [Hb], protection from AMS, retention of exercise performance, less retention of cognitive function; and noted that some of these effects lasted for 21 days. Taken together, these findings reveal new information about retention of acclimatization, and can be used as a physiological foundation to explore the molecular mechanisms of acclimatization and its retention

    Incorporating feasibility and collaboration into large-scale planning for regional recovery of coral reef fisheries

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    Broad-scale overharvesting of fish is one of the major drivers of marine biodiversity loss and poverty, particularly in countries with high dependence on coral reefs. Given the heterogeneity of fishing effort and management success, and the scarcity of management resources, it is necessary to identify broad-scale locations for promoting successful fisheries management and conservation. Here, we assessed how fisheries management and conservation priorities in the Western Indian Ocean would change if the objectives were to (1) minimize lost fishing opportunity, (2) minimize the time for fish biomass to recover, (3) avoid locations of low management feasibility based on historical management outcomes, and (4) incorporate international collaboration to optimize the rate for achieving goals. When prioritizing for rapid recovery of fish biomass rather than minimizing lost fishing opportunity, we found that the area of priority management zones changed by over 60% in some countries. When locations of low management feasibility were avoided, the recovery time of fish biomass across the region increased 4-fold. International collaborations prioritized management zones in remote, high biomass, and low fishing pressure reefs and reduced the recovery time of fish 5-fold compared to non-collaboration scenarios. Thus, many of these conservation objectives favored wealthy and sparsely populated over poorer and natural resource dependent countries. Consequently, this study shows how prioritization policies, incentives, decisions, and conflicts will produce highly variable outcomes and challenges for sustainability

    Management of systemic lupus erythematosus

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    No Abstract.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/37693/1/1780050510_ftp.pd
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