Institution
University of Maine
Education•Orono, Maine, United States•
About: University of Maine is a education organization based out in Orono, Maine, United States. It is known for research contribution in the topics: Population & Ice sheet. The organization has 8637 authors who have published 16932 publications receiving 590124 citations. The organization is also known as: University of Maine at Orono.
Topics: Population, Ice sheet, Climate change, Glacial period, Glacier
Papers published on a yearly basis
Papers
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TL;DR: In this paper, the relative influence of divergent selection and geographic features on gene flow among populations of Trinidadian guppies (Poecilia reticulata) was determined.
Abstract: Two general processes may influence gene flow among populations. One involves divergent selection, wherein the maladaptation of immigrants and hybrids impedes gene flow between ecological environments (i.e. ecological speciation). The other involves geographic features that limit dispersal. We determined the relative influence of these two processes in natural populations of Trinidadian guppies ( Poecilia reticulata ). If selection is important, gene flow should be reduced between different selective environments. If geography is important, gene flow should be impeded by geographic distance and physical barriers. We examined how genetic divergence, long-term gene flow, and contemporary dispersal within a watershed were influenced by waterfalls, geographic distance, predation, and habitat features. We found that waterfalls and geographic distance increased genetic divergence and reduced dispersal and long-term gene flow. Differences in predation or habitat features did not influence genetic divergence or gene flow. In contrast, differences in predation did appear to reduce contemporary dispersal. We suggest that the standard predictions of ecological speciation may be heavily nuanced by the mating behaviour and life history strategies of guppies.
304 citations
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TL;DR: Porphyra umbilicalis genome project will further elucidate proteins associated with stress tolerance, and phylogenomic and transcriptomic investigations of Porphyra sensu lato could elucidate tradeoffs made during physiological acclimation and factors associated with life-history evolution in this ancient lineage.
303 citations
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TL;DR: The concentrations of polybrominated diphenyl ethers in harbor seals in the San Francisco Bay have increased dramatically over the past decade, with current levels among the highest reported for this species.
303 citations
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Abstract: This article examines the evolving definition of transparency from a postmodernist approach. It traces the meaning of transparency from its use by nongovernmental and supranational organizations to its use in the international relations, nonprofit, public policy, and administration literature. It finds that the definition of transparency reveals three metaphors: transparency as a public value embraced by society to counter corruption, transparency synonymous with open decision-making by governments and nonprofits, and transparency as a complex tool of good governance in programs, policies, organizations, and nations. In the first metaphor, transparency is subtly intertwined with accountability. In the second, as transparency encourages openness, it increases concerns for secrecy and privacy. In the third, policymakers create transparency alongside accountability, efficiency, and effectiveness. The analysis concludes that these meanings affect the way organization members conduct and will conduct their day...
303 citations
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TL;DR: In this paper, the authors evaluate the physiological underpinnings of global variations in satellite-based phytoplankton chlorophyll fluorescence and find that the three dominant factors influencing fluorescence distributions are chilophyll concentration, pigment packaging effects on light absorption, and light-dependent energy-quenching processes.
Abstract: . Phytoplankton photosynthesis links global ocean biology and climate-driven fluctuations in the physical environment. These interactions are largely expressed through changes in phytoplankton physiology, but physiological status has proven extremely challenging to characterize globally. Phytoplankton fluorescence does provide a rich source of physiological information long exploited in laboratory and field studies, and is now observed from space. Here we evaluate the physiological underpinnings of global variations in satellite-based phytoplankton chlorophyll fluorescence. The three dominant factors influencing fluorescence distributions are chlorophyll concentration, pigment packaging effects on light absorption, and light-dependent energy-quenching processes. After accounting for these three factors, resultant global distributions of quenching-corrected fluorescence quantum yields reveal a striking consistency with anticipated patterns of iron availability. High fluorescence quantum yields are typically found in low iron waters, while low quantum yields dominate regions where other environmental factors are most limiting to phytoplankton growth. Specific properties of photosynthetic membranes are discussed that provide a mechanistic view linking iron stress to satellite-detected fluorescence. Our results present satellite-based fluorescence as a valuable tool for evaluating nutrient stress predictions in ocean ecosystem models and give the first synoptic observational evidence that iron plays an important role in seasonal phytoplankton dynamics of the Indian Ocean. Satellite fluorescence may also provide a path for monitoring climate-phytoplankton physiology interactions and improving descriptions of phytoplankton light use efficiencies in ocean productivity models.
302 citations
Authors
Showing all 8729 results
Name | H-index | Papers | Citations |
---|---|---|---|
Clifford J. Rosen | 111 | 655 | 47881 |
Juan S. Bonifacino | 108 | 303 | 46554 |
John D. Aber | 107 | 204 | 48500 |
Surendra P. Shah | 99 | 710 | 32832 |
Charles T. Driscoll | 97 | 554 | 37355 |
Samuel Madden | 95 | 388 | 46424 |
Lihua Xiao | 93 | 495 | 32721 |
Patrick G. Hatcher | 91 | 401 | 27519 |
Pedro J. J. Alvarez | 89 | 378 | 34837 |
George R. Pettit | 89 | 848 | 31759 |
James R. Wilson | 89 | 1271 | 37470 |
Steven Girvin | 86 | 366 | 38963 |
Peter Marler | 81 | 174 | 22070 |
Garry R. Buettner | 80 | 304 | 29273 |
Paul Andrew Mayewski | 80 | 420 | 29356 |