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When faced with a problem, how do individuals search for potential solutions? In this article, we explore the cognitive processes that lead to local search (i.e., identifying options closest to existing solutions) and distant search (i.e., identifying options of a qualitatively different nature than existing solutions). We suggest that mind wandering is likely to lead to local search because it operates by spreading activation from initial ideas to closely associated ideas. This reduces the likelihood of accessing a qualitatively different solution. However, instead of getting lost in thought, individuals can also step back and monitor their thoughts from a detached perspective. Such mindful metacognition, we suggest, is likely to lead to distant search because it redistributes activation away from initial ideas to other, less strongly associated, ideas. This hypothesis was confirmed across two studies. Thus, getting lost in thoughts is helpful when one is on the right track and needs only a local search whereas stepping back from thoughts is helpful when one needs distant search to produce a change in perspective. 相似文献
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Adenosine is an important mediator of inhibition of platelet activation. This metabolite is released from various cells, as well as generated via activity of ecto‐enzymes on the cell surface. Binding of adenosine to A2 subtypes (A2A or A2B), G‐protein coupled adenosine receptors, results in increased levels of intracellular cyclic adenosine monophosphate (cAMP), a strong inhibitor of platelet activation. The role and importance of adenosine and its receptors in platelet physiology are addressed in this review, including recently identified roles for the A2B adenosine receptor as a modulator of platelet activation through its newly described role in the control of expression of adenosine diphosphate (ADP) receptors. J. Cell. Physiol. 226: 46–51, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
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Matthias Albrecht David Kleijn Neal M. Williams Matthias Tschumi Brett R. Blaauw Riccardo Bommarco Alistair J. Campbell Matteo Dainese Francis A. Drummond Martin H. Entling Dominik Ganser G. Arjen de Groot Dave Goulson Heather Grab Hannah Hamilton Felix Herzog Rufus Isaacs Katja Jacot Philippe Jeanneret Mattias Jonsson Eva Knop Claire Kremen Douglas A. Landis Gregory M. Loeb Lorenzo Marini Megan McKerchar Lora Morandin Sonja C. Pfister Simon G. Potts Maj Rundlf Hillary Sardias Amber Sciligo Carsten Thies Teja Tscharntke Eric Venturini Eve Veromann Ines M.G. Vollhardt Felix Wckers Kimiora Ward Andrew Wilby Megan Woltz Steve Wratten Louis Sutter 《Ecology letters》2020,23(10):1488-1498
Floral plantings are promoted to foster ecological intensification of agriculture through provisioning of ecosystem services. However, a comprehensive assessment of the effectiveness of different floral plantings, their characteristics and consequences for crop yield is lacking. Here we quantified the impacts of flower strips and hedgerows on pest control (18 studies) and pollination services (17 studies) in adjacent crops in North America, Europe and New Zealand. Flower strips, but not hedgerows, enhanced pest control services in adjacent fields by 16% on average. However, effects on crop pollination and yield were more variable. Our synthesis identifies several important drivers of variability in effectiveness of plantings: pollination services declined exponentially with distance from plantings, and perennial and older flower strips with higher flowering plant diversity enhanced pollination more effectively. These findings provide promising pathways to optimise floral plantings to more effectively contribute to ecosystem service delivery and ecological intensification of agriculture in the future. 相似文献
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Hillary C. Maddin Nadine Piekarski Robert R. Reisz James Hanken 《Biological reviews of the Cambridge Philosophical Society》2020,95(3):573-591
The origin and evolution of the vertebrate skull have been topics of intense study for more than two centuries. Whereas early theories of skull origin, such as the influential vertebral theory, have been largely refuted with respect to the anterior (pre‐otic) region of the skull, the posterior (post‐otic) region is known to be derived from the anteriormost paraxial segments, i.e. the somites. Here we review the morphology and development of the occiput in both living and extinct tetrapods, taking into account revised knowledge of skull development by augmenting historical accounts with recent data. When occipital composition is evaluated relative to its position along the neural axis, and specifically to the hypoglossal nerve complex, much of the apparent interspecific variation in the location of the skull–neck boundary stabilizes in a phylogenetically informative way. Based on this criterion, three distinct conditions are identified in (i) frogs, (ii) salamanders and caecilians, and (iii) amniotes. The position of the posteriormost occipital segment relative to the hypoglossal nerve is key to understanding the evolution of the posterior limit of the skull. By using cranial foramina as osteological proxies of the hypoglossal nerve, a survey of fossil taxa reveals the amniote condition to be present at the base of Tetrapoda. This result challenges traditional theories of cranial evolution, which posit translocation of the occiput to a more posterior location in amniotes relative to lissamphibians (frogs, salamanders, caecilians), and instead supports the largely overlooked hypothesis that the reduced occiput in lissamphibians is secondarily derived. Recent advances in our understanding of the genetic basis of axial patterning and its regulation in amniotes support the hypothesis that the lissamphibian occipital form may have arisen as the product of a homeotic shift in segment fate from an amniote‐like condition. 相似文献
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Goldberg E. Grace Raab Ted K. Desalles Paul Briggs Amy A. Dunbar Robert B. Millero Frank J. Woosley Ryan J. Young Hillary S. Micheli Fiorenza Mccauley Douglas J. 《Coral reefs (Online)》2019,38(2):347-357
Coral Reefs - Bolbometopon muricatum are ecologically unique mega-consumers in coral reef ecosystems. They primarily divide their dietary intake between living scleractinian corals and coral rock,... 相似文献
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Anne M. Rice Ryan Mahling Michael E. Fealey Anika Rannikko Katie Dunleavy Troy Hendrickson K. Jean Lohese Spencer Kruggel Hillary Heiling Daniel Harren R. Bryan Sutton John Pastor Anne Hinderliter 《生物化学与生物物理学报:生物膜》2014
Eukaryotic lipids in a bilayer are dominated by weak cooperative interactions. These interactions impart highly dynamic and pliable properties to the membrane. C2 domain-containing proteins in the membrane also interact weakly and cooperatively giving rise to a high degree of conformational plasticity. We propose that this feature of weak energetics and plasticity shared by lipids and C2 domain-containing proteins enhance a cell's ability to transduce information across the membrane. We explored this hypothesis using information theory to assess the information storage capacity of model and mast cell membranes, as well as differential scanning calorimetry, carboxyfluorescein release assays, and tryptophan fluorescence to assess protein and membrane stability. The distribution of lipids in mast cell membranes encoded 5.6–5.8 bits of information. More information resided in the acyl chains than the head groups and in the inner leaflet of the plasma membrane than the outer leaflet. When the lipid composition and information content of model membranes were varied, the associated C2 domains underwent large changes in stability and denaturation profile. The C2 domain-containing proteins are therefore acutely sensitive to the composition and information content of their associated lipids. Together, these findings suggest that the maximum flow of signaling information through the membrane and into the cell is optimized by the cooperation of near-random distributions of membrane lipids and proteins. This article is part of a Special Issue entitled: Interfacially Active Peptides and Proteins. Guest Editors: William C. Wimley and Kalina Hristova. 相似文献
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Laurence Rohmer Michael A Jacobs Mitchell J Brittnacher Christine Fong Hillary S Hayden Didier Hocquet Eli J Weiss Matthew Radey Yves Germani Kaisar Ali Talukder Anthony J Hager John M Kemner Elizabeth H Sims-Day Susana Matamouros Kyle R Hager Samuel I Miller 《BMC genomics》2014,15(1)