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, Glacial period, Glacier, Ice core
Papers published on a yearly basis
Papers
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TL;DR: In this article, the authors used two models, PnET-BGC and WATERSN, to evaluate management strategies for reducing anthropogenic nitrogen inputs to forests and estuaries, respectively.
Abstract: The northeastern United States receives elevated inputs of anthropogenic nitrogen (N) largely from net imports of food and atmospheric deposition, with lesser inputs from fertilizer, net feed imports, and N fixation associated with leguminous crops. Ecological consequences of elevated N inputs to the Northeast include tropospheric ozone formation, ozone damage to plants, the alteration of forest N cycles, acidification of surface waters, and eutrophication in coastal waters. We used two models, PnET-BGC and WATERSN, to evaluate management strategies for reducing N inputs to forests and estuaries, respectively. Calculations with PnET-BGC suggest that aggressive reductions in N emissions alone will not result in marked improvements in the acid–base status of forest streams. WATERSN calculations showed that management scenarios targeting removal of N by wastewater treatment produce larger reductions in estuarine N loading than scenarios involving reductions in agricultural inputs or atmospheric emis...
428 citations
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01 Oct 1998TL;DR: A thorough review of psychometric techniques for the study of creativity benefits both those individuals attempting to measure creativity and those individuals studying creativity via other techniques can be found in this paper, where the authors present a survey of the psychometric studies of creativity.
Abstract: The study of human creativity, although historically extensive, is in the midst of a second golden age as the century comes to a close. Authors and researchers from a variety of backgrounds publish hundreds of articles and books on creativity every year, conferences that cross disciplines frequently include sessions on creativity, and programs for increasing the creative productivity of young people and adults are introduced on a regular basis. And while several distinct approaches are used to examine creative phenomenon, a majority of work dealing with creativity relies on psychometric methods - the direct measurement of creativity and/or its perceived correlates in individuals. Indeed, practically all current work on creativity is based upon methodologies that either are psychometric in nature or were developed in response to perceived weaknesses of creativity measurement. As such, the psychometric studies of creativity conducted in the past few decades form the foundation of current understandings of creativity. Yet the psychometric approach is significantly more complex and comprehensive than its critics (and many of its proponents) would have us believe, and alternatives to the psychometric approach are wrought with many of the same difficulties posed during the direct measurement of creativity. A thorough review of psychometric techniques for the study of creativity benefits both those individuals attempting to measure creativity and those individuals studying creativity via other techniques.
426 citations
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University of Hawaii at Manoa1, Duke University2, University of Maine3, Moss Landing Marine Laboratories4, University of Connecticut5, Dalhousie University6, Carnegie Institution for Science7, Harvard University8, University of Maryland, College Park9, Skidaway Institute of Oceanography10, University of Delaware11
TL;DR: Iron budgets are consistent with the notions that new production is determined by the rate of new iron input to the system while total production depends on efficient iron recycling by grazers and the interactions of resource limitation and grazing in HNLC regions are conceptually similar.
Abstract: Recent studies in the central equatorial Pacific allow a comprehensive assessment of phytoplankton regulation in a high-nutrient, low-chlorophyll (HNLC) ecosystem. Elemental iron enters the euphotic zone principally via upwelling and is present at concentrations (530 PM) well below the estimated half-saturation constant (120 PM) for the large cells that bloom with iron enrichment. In addition, the meridional trend in quantum yield of photosynthesis suggests that even the dominant small phytoplankton are held below their physiological potential by iron deficiency. Grazing by microzooplankton dominates phytoplankton losses, accounting for virtually all of the measured phytoplankton production during El Nina conditions and -66% during normal upwelling conditions, with mesozooplankton grazing and lateral advection closing the balance. Nitrate uptake is strongly correlated with the pigment biomass of diatoms, which increase in relative abundance during normal upwelling conditions. Nonetheless, the f-ratio remains low (0.07-0.12) under all conditions. Iron budgets are consistent with the notions that new production is determined by the rate of new iron input to the system while total production depends on efficient iron recycling by grazers. Although the limiting substrates differ, the interactions of resource limitation and grazing in HNLC regions are conceptually similar to the generally accepted view for oligotrophic subtropical regions. In both systems, small dominant phytoplankton grow at rapid, but usually less than physiologically maximal, rates; they are cropped to low stable abundances by microzooplankton; and their sustained high rates of growth depend on the remineralized by-products of grazing.
423 citations
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422 citations
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TL;DR: This target article sketches the evidence from five domains that bear on the explanatory adequacy of cultural group selection and competing hypotheses to explain human cooperation and presents evidence, including quantitative evidence, that the answer to all of the questions is “yes” and argues that it is not clear that any extant alternative tocultural group selection can be a complete explanation.
Abstract: Human cooperation is highly unusual. We live in large groups composed mostly of non-relatives. Evolutionists have proposed a number of explanations for this pattern, including cultural group selection and extensions of more general processes such as reciprocity, kin selection, and multi-level selection acting on genes. Evolutionary processes are consilient; they affect several different empirical domains, such as patterns of behavior and the proximal drivers of that behavior. In this target article, we sketch the evidence from five domains that bear on the explanatory adequacy of cultural group selection and competing hypotheses to explain human cooperation. Does cultural transmission constitute an inheritance system that can evolve in a Darwinian fashion? Are the norms that underpin institutions among the cultural traits so transmitted? Do we observe sufficient variation at the level of groups of considerable size for group selection to be a plausible process? Do human groups compete, and do success and failure in competition depend upon cultural variation? Do we observe adaptations for cooperation in humans that most plausibly arose by cultural group selection? If the answer to one of these questions is "no," then we must look to other hypotheses. We present evidence, including quantitative evidence, that the answer to all of the questions is "yes" and argue that we must take the cultural group selection hypothesis seriously. If culturally transmitted systems of rules (institutions) that limit individual deviance organize cooperation in human societies, then it is not clear that any extant alternative to cultural group selection can be a complete explanation.
422 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 |