110 research outputs found

    Gratitude and Happiness: The Causes and Consequences of Gratitude

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    In this chapter, we review recent research on the relationship between gratitude and happiness. First, we show how gratitude is a critical component of the good life. Because gratitude is vital to wellbeing, it is important to establish the causes of state and trait gratitude. We explain an appraisal approach to grateful emotion and show how certain benefit interpretations are critical to the experience of gratitude. In this context, we describe an encouraging new paradigm that has been applied to the study of gratitude: cognitive bias modification. This experimental approach has helped to establish the causal status of interpretations to gratitude, and we describe how this methodology should help to understand gratitude in future research. Recent research on the cognitive antecedents of gratitude has shown that the nature of the benefactor matters to experiences of gratitude, and in this regard, a divine benefactor may create a unique experience of gratitude. Gratitude scholars have now turned to the question: How does gratitude enhance happiness? We present research and theories that have attempted to speak to this issue. Finally, we explore the question: Who benefits most from gratitude interventions? Research has supplied some surprising answers to this question

    Extrasolar planet population synthesis IV. Correlations with disk metallicity, mass and lifetime

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    Context. This is the fourth paper in a series showing the results of planet population synthesis calculations. Aims. Our goal in this paper is to systematically study the effects of important disk properties, namely disk metallicity, mass and lifetime on fundamental planetary properties. Methods. For a large number of protoplanetary disks we calculate a population of planets with our core accretion formation model including planet migration and disk evolution. Results. We find a large number of correlations: Regarding the planetary initial mass function, metallicity, disk mass and disk lifetime have different roles: For high [Fe/H], giant planets are more frequent. For high disk masses, giant planets are more massive. For long disk lifetimes, giant planets are both more frequent and massive. At low metallicities, very massive giant planets cannot form, but otherwise giant planet mass and metallicity are uncorrelated. In contrast, planet masses and disk gas masses are correlated. The sweet spot for giant planet formation is at 5 AU. In- and outside this distance, higher planetesimals surface densities are necessary. Low metallicities can be compensated by high disk masses, and vice versa, but not ad infinitum. At low metallicities, giant planets only form outside the ice line, while at high metallicities, giant planet formation occurs throughout the disk. The extent of migration increases with disk mass and lifetime and usually decreases with metallicity. No clear correlation of metallicity and the semimajor axis of giant planets exists because in low [Fe/H] disks, planets start further out, but migrate more, whereas for high [Fe/H] they start further in, but migrate less. Close-in low mass planets have a lower mean metallicity than Hot Jupiters. Conclusions. The properties of protoplanetary disks are decisive for the properties of planets, and leave many imprints.Comment: 23 pages, 16 figures. Accepted for A&

    Perspectives on Implementing a Multidomain Approach to Caring for Older Adults With Heart Failure

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    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/153220/1/jgs16183_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/153220/2/jgs16183-sup-0001-supinfo.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/153220/3/jgs16183.pd

    A Spitzer IRS Survey of NGC 1333: Insights into disk evolution from a very young cluster

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    We report on the {\lambda} = 5-36{\mu}m Spitzer Infrared Spectrograph spectra of 79 young stellar objects in the very young nearby cluster NGC 1333. NGC 1333's youth enables the study of early protoplanetary disk properties, such as the degree of settling as well as the formation of gaps and clearings. We construct spectral energy distributions (SEDs) using our IRS data as well as published photometry and classify our sample into SED classes. Using "extinction-free" spectral indices, we determine whether the disk, envelope, or photosphere dominates the spectrum. We analyze the dereddened spectra of objects which show disk dominated emission using spectral indices and properties of silicate features in order to study the vertical and radial structure of protoplanetary disks in NGC 1333. At least nine objects in our sample of NGC 1333 show signs of large (several AU) radial gaps or clearings in their inner disk. Disks with radial gaps in NGC 1333 show more-nearly pristine silicate dust than their radially continuous counterparts. We compare properties of disks in NGC 1333 to those in three other well studied regions, Taurus-Auriga, Ophiuchus and Chamaeleon I, and find no difference in their degree of sedimentation and dust processing.Comment: 67 pages, 20 figures, accepted to The Astrophysical Journal Supplement Serie

    Large-Range Movements of Neotropical Orchid Bees Observed via Radio Telemetry

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    Neotropical orchid bees (Euglossini) are often cited as classic examples of trapline-foragers with potentially extensive foraging ranges. If long-distance movements are habitual, rare plants in widely scattered locations may benefit from euglossine pollination services. Here we report the first successful use of micro radio telemetry to track the movement of an insect pollinator in a complex and forested environment. Our results indicate that individual male orchid bees (Exaerete frontalis) habitually use large rainforest areas (at least 42–115 ha) on a daily basis. Aerial telemetry located individuals up to 5 km away from their core areas, and bees were often stationary, for variable periods, between flights to successive localities. These data suggest a higher degree of site fidelity than what may be expected in a free living male bee, and has implications for our understanding of biological activity patterns and the evolution of forest pollinators

    The composition of the protosolar disk and the formation conditions for comets

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    Conditions in the protosolar nebula have left their mark in the composition of cometary volatiles, thought to be some of the most pristine material in the solar system. Cometary compositions represent the end point of processing that began in the parent molecular cloud core and continued through the collapse of that core to form the protosun and the solar nebula, and finally during the evolution of the solar nebula itself as the cometary bodies were accreting. Disentangling the effects of the various epochs on the final composition of a comet is complicated. But comets are not the only source of information about the solar nebula. Protostellar disks around young stars similar to the protosun provide a way of investigating the evolution of disks similar to the solar nebula while they are in the process of evolving to form their own solar systems. In this way we can learn about the physical and chemical conditions under which comets formed, and about the types of dynamical processing that shaped the solar system we see today. This paper summarizes some recent contributions to our understanding of both cometary volatiles and the composition, structure and evolution of protostellar disks.Comment: To appear in Space Science Reviews. The final publication is available at Springer via http://dx.doi.org/10.1007/s11214-015-0167-

    An Observational Overview of Solar Flares

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    We present an overview of solar flares and associated phenomena, drawing upon a wide range of observational data primarily from the RHESSI era. Following an introductory discussion and overview of the status of observational capabilities, the article is split into topical sections which deal with different areas of flare phenomena (footpoints and ribbons, coronal sources, relationship to coronal mass ejections) and their interconnections. We also discuss flare soft X-ray spectroscopy and the energetics of the process. The emphasis is to describe the observations from multiple points of view, while bearing in mind the models that link them to each other and to theory. The present theoretical and observational understanding of solar flares is far from complete, so we conclude with a brief discussion of models, and a list of missing but important observations.Comment: This is an article for a monograph on the physics of solar flares, inspired by RHESSI observations. The individual articles are to appear in Space Science Reviews (2011
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