Publications by authors named "Henry Gregory"

Article Synopsis
  • HD 189733b is a key exoplanet for studying atmospheres, providing insights into composition, chemistry, and atmospheric dynamics.
  • Previous studies identified molecules like HO and CO in its atmosphere, but some findings about methane have been disputed.
  • Recent observations detect HO, CO, and HS, leading to an inferred atmosphere metallicity three to five times that of its star, suggesting formation from water-rich icy planetesimals.
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There are no planets intermediate in size between Earth and Neptune in our Solar System, yet these objects are found around a substantial fraction of other stars. Population statistics show that close-in planets in this size range bifurcate into two classes on the basis of their radii. It is proposed that the group with larger radii (referred to as 'sub-Neptunes') is distinguished by having hydrogen-dominated atmospheres that are a few percent of the total mass of the planets.

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The tundra is warming more rapidly than any other biome on Earth, and the potential ramifications are far-reaching because of global feedback effects between vegetation and climate. A better understanding of how environmental factors shape plant structure and function is crucial for predicting the consequences of environmental change for ecosystem functioning. Here we explore the biome-wide relationships between temperature, moisture and seven key plant functional traits both across space and over three decades of warming at 117 tundra locations.

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Arctic climate warming will be primarily during winter, resulting in increased snowfall in many regions. Previous tundra research on the impacts of deepened snow has generally been of short duration. Here, we report relatively long-term (7-9 years) effects of experimentally deepened snow on plant community structure, net ecosystem CO exchange (NEE), and soil biogeochemistry in Canadian Low Arctic mesic shrub tundra.

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The angle between the spin of a star and the orbital planes of its planets traces the history of the planetary system. Exoplanets orbiting close to cool stars are expected to be on circular, aligned orbits because of strong tidal interactions with the stellar convective envelope. Spin-orbit alignment can be measured when the planet transits its star, but such ground-based spectroscopic measurements are challenging for cool, slowly rotating stars.

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Infrared radiation emitted from a planet contains information about the chemical composition and vertical temperature profile of its atmosphere. If upper layers are cooler than lower layers, molecular gases will produce absorption features in the planetary thermal spectrum. Conversely, if there is a stratosphere-where temperature increases with altitude-these molecular features will be observed in emission.

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Warmer temperatures are accelerating the phenology of organisms around the world. Temperature sensitivity of phenology might be greater in colder, higher latitude sites than in warmer regions, in part because small changes in temperature constitute greater relative changes in thermal balance at colder sites. To test this hypothesis, we examined up to 20 years of phenology data for 47 tundra plant species at 18 high-latitude sites along a climatic gradient.

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Rapidly rising temperatures are expected to cause latitudinal and elevational range shifts as species track their optimal climate north and upward. However, a lack of adaptation to environmental conditions other than climate - for example photoperiod, biotic interactions, or edaphic conditions - might limit the success of immigrants in a new location despite hospitable climatic conditions. Here, we present one of the first direct experimental tests of the hypothesis that warmer temperatures at northern latitudes will confer a fitness advantage to southern immigrants relative to native populations.

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Recovery from substance abuse and mental health disorders represents a journey through which individuals move beyond treatment of provider-identified problems toward a path of achieving wellness and productive lives. Overcoming obstacles and barriers encountered along the recovery process, individuals reveal their own strengths and resilience necessary to cope, survive, and thrive in the face of adversity. Recovery-oriented system of care (ROSC) is a framework designed to address the multidimensional nature of recovery by creating a system for coordinating multiple systems, services, and supports that are person centered and build on the strengths and resiliencies of individuals, families, and communities.

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Thousands of transiting exoplanets have been discovered, but spectral analysis of their atmospheres has so far been dominated by a small number of exoplanets and data spanning relatively narrow wavelength ranges (such as 1.1-1.7 micrometres).

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Recent changes in climate have led to significant shifts in phenology, with many studies demonstrating advanced phenology in response to warming temperatures. The rate of temperature change is especially high in the Arctic, but this is also where we have relatively little data on phenological changes and the processes driving these changes. In order to understand how Arctic plant species are likely to respond to future changes in climate, we monitored flowering phenology in response to both experimental and ambient warming for four widespread species in two habitat types over 21 years.

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Inference about future climate change impacts typically relies on one of three approaches: manipulative experiments, historical comparisons (broadly defined to include monitoring the response to ambient climate fluctuations using repeat sampling of plots, dendroecology, and paleoecology techniques), and space-for-time substitutions derived from sampling along environmental gradients. Potential limitations of all three approaches are recognized. Here we address the congruence among these three main approaches by comparing the degree to which tundra plant community composition changes (i) in response to in situ experimental warming, (ii) with interannual variability in summer temperature within sites, and (iii) over spatial gradients in summer temperature.

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Exoplanets that orbit close to their host stars are much more highly irradiated than their solar system counterparts. Understanding the thermal structures and appearances of these planets requires investigating how their atmospheres respond to such extreme stellar forcing. We present spectroscopic thermal emission measurements as a function of orbital phase ("phase-curve observations") for the highly irradiated exoplanet WASP-43b spanning three full planet rotations using the Hubble Space Telescope.

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The northern boundary of boreal forest and the ranges of tree species are expected to shift northward in response to climate warming, which will result in a decrease in the albedo of areas currently covered by tundra vegetation, an increase in terrestrial carbon sequestration, and an alteration of biodiversity in the current Low Arctic. Central to the prediction of forest expansion is an increase in the reproductive capacity and establishment of individual trees. We assessed cone production, seed viability, and transplanted seedling success of Picea glauca (Moench.

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The UMBC Psychology Department's Center for Community Collaboration (CCC) provides training and support for capacity building to promote substance abuse and mental health treatment as well as adherence improvement in community agencies funded through the Ryan White Act serving persons living with HIV/AIDS. This article describes an approach to dissemination of Evidence Based Practices (EBPs) for these services that uses the Interactive Systems Framework (ISF) and incorporates a collaborative process involving trainer cultural competence, along with a comprehensive assessment of organizational needs, culture, and climate that culminates in tailored training and ongoing collaboration. This article provides: (1) an overview of the CCC's expanded ISF for the effective dissemination of two EBPs-motivational interviewing and the stages of change perspective; (2) an examination of the role of trainer cultural competence within the ISF framework, particularly attending to organizational culture and climate; and (3) case examples to demonstrate this approach for both general and innovation-specific capacity building in two community based organizations.

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Understanding the sensitivity of tundra vegetation to climate warming is critical to forecasting future biodiversity and vegetation feedbacks to climate. In situ warming experiments accelerate climate change on a small scale to forecast responses of local plant communities. Limitations of this approach include the apparent site-specificity of results and uncertainty about the power of short-term studies to anticipate longer term change.

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Arctic air temperatures are expected to rise significantly over the next century. Experimental warming of arctic tundra has been shown to increase plant productivity and cause community shifts and may also alter microbial community structure. Hence, the objective of this study was to determine whether experimental warming caused shifts in soil microbial communities by measuring changes in the frequency, relative abundance and/or richness of nosZ and nifH genotypes.

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The effect of experimental warming on the root-associated fungal community of arctic willow (Salix arctica) was studied in three distinct habitats at a tundra site in the Canadian High Arctic. Plots were passively warmed for 5-7 years using open-top chambers and compared to control plots at ambient temperature. Fungal communities were assessed using terminal restriction fragment length polymorphisms.

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