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Showing papers by "University of Maine published in 2012"


Journal ArticleDOI
TL;DR: New T-statistics ('T' for trait) are introduced, based on the comparison of intraspecific and interspecific variances of functional traits across organizational levels, to operationally incorporate intrapecific variability into community ecology theory.
Abstract: Despite being recognized as a promoter of diversity and a condition for local coexistence decades ago, the importance of intraspecific variance has been neglected over time in community ecology. Recently, there has been a new emphasis on intraspecific variability. Indeed, recent developments in trait-based community ecology have underlined the need to integrate variation at both the intraspecific as well as interspecific level. We introduce new T-statistics ('T' for trait), based on the comparison of intraspecific and interspecific variances of functional traits across organizational levels, to operationally incorporate intraspecific variability into community ecology theory. We show that a focus on the distribution of traits at local and regional scales combined with original analytical tools can provide unique insights into the primary forces structuring communities.

1,304 citations


Journal ArticleDOI
Ward Appeltans1, Shane T. Ahyong2, Shane T. Ahyong3, Gary L. Anderson4, Martin V. Angel5, Tom Artois6, Nicolas Bailly7, Roger N. Bamber, Anthony Barber, Ilse Bartsch8, Annalisa Berta9, Magdalena Błażewicz-Paszkowycz, Phil Bock10, Geoff A. Boxshall11, Christopher B. Boyko12, Simone N. Brandão13, R. A. Bray11, Niel L. Bruce14, Niel L. Bruce15, Stephen D. Cairns16, Tin-Yam Chan17, Lanna Cheng18, Allen Gilbert Collins19, Thomas H. Cribb20, Marco Curini-Galletti21, Farid Dahdouh-Guebas22, Farid Dahdouh-Guebas23, Peter J. F. Davie24, Michael N Dawson25, Olivier De Clerck26, Wim Decock1, Sammy De Grave8, Nicole J. de Voogd27, Daryl P. Domning28, Christian C. Emig, Christer Erséus29, William N. Eschmeyer30, William N. Eschmeyer31, Kristian Fauchald16, Daphne G. Fautin8, Stephen W. Feist32, Charles H. J. M. Fransen27, Hidetaka Furuya33, Óscar García-Álvarez34, Sarah Gerken35, David I. Gibson11, Arjan Gittenberger27, Serge Gofas36, Liza Gómez-Daglio25, Dennis P. Gordon37, Michael D. Guiry38, Francisco Hernandez1, Bert W. Hoeksema27, Russell R. Hopcroft39, Damià Jaume40, Paul M. Kirk41, Nico Koedam22, Stefan Koenemann42, Jürgen B. Kolb43, Reinhardt Møbjerg Kristensen44, Andreas Kroh45, Gretchen Lambert46, David Lazarus47, Rafael Lemaitre16, Matt Longshaw32, Jim Lowry2, Enrique Macpherson40, Laurence P. Madin48, Christopher L. Mah16, Gill Mapstone11, Patsy A. McLaughlin49, Jan Mees1, Jan Mees26, Kenneth Meland50, Charles G. Messing51, Claudia E. Mills46, Tina N. Molodtsova52, Rich Mooi30, Birger Neuhaus47, Peter K. L. Ng53, Claus Nielsen44, Jon L. Norenburg16, Dennis M. Opresko16, Masayuki Osawa54, Gustav Paulay31, William F. Perrin19, John F. Pilger55, Gary C. B. Poore10, P.R. Pugh5, Geoffrey B. Read37, James Davis Reimer56, Marc Rius57, Rosana M. Rocha58, J.I. Saiz-Salinas59, Victor Scarabino, Bernd Schierwater60, Andreas Schmidt-Rhaesa13, Kareen E. Schnabel37, Marilyn Schotte16, Peter Schuchert, Enrico Schwabe, Hendrik Segers61, Caryn Self-Sullivan51, Noa Shenkar62, Volker Siegel, Wolfgang Sterrer8, Sabine Stöhr63, Billie J. Swalla46, Mark L. Tasker64, Erik V. Thuesen65, Tarmo Timm66, M. Antonio Todaro, Xavier Turon40, Seth Tyler67, Peter Uetz68, Jacob van der Land27, Bart Vanhoorne1, Leen van Ofwegen27, Rob W. M. Van Soest27, Jan Vanaverbeke26, Genefor Walker-Smith10, T. Chad Walter16, Alan Warren11, Gary C. Williams30, Simon P. Wilson69, Mark J. Costello70 
Flanders Marine Institute1, Australian Museum2, University of New South Wales3, University of Southern Mississippi4, National Oceanography Centre, Southampton5, University of Hasselt6, WorldFish7, American Museum of Natural History8, San Diego State University9, Museum Victoria10, Natural History Museum11, Dowling College12, University of Hamburg13, University of Johannesburg14, James Cook University15, National Museum of Natural History16, National Taiwan Ocean University17, Scripps Institution of Oceanography18, National Oceanic and Atmospheric Administration19, University of Queensland20, University of Sassari21, Vrije Universiteit Brussel22, Université libre de Bruxelles23, Queensland Museum24, University of California, Merced25, Ghent University26, Naturalis27, Howard University28, University of Gothenburg29, California Academy of Sciences30, Florida Museum of Natural History31, Centre for Environment, Fisheries and Aquaculture Science32, Osaka University33, University of Santiago de Compostela34, University of Alaska Anchorage35, University of Málaga36, National Institute of Water and Atmospheric Research37, National University of Ireland, Galway38, University of Alaska Fairbanks39, Spanish National Research Council40, CABI41, University of Siegen42, Massey University43, University of Copenhagen44, Naturhistorisches Museum45, University of Washington46, Museum für Naturkunde47, Woods Hole Oceanographic Institution48, Western Washington University49, University of Bergen50, Nova Southeastern University51, Shirshov Institute of Oceanology52, National University of Singapore53, Shimane University54, Agnes Scott College55, University of the Ryukyus56, University of California, Davis57, Federal University of Paraná58, University of the Basque Country59, University of Veterinary Medicine Hanover60, Royal Belgian Institute of Natural Sciences61, Tel Aviv University62, Swedish Museum of Natural History63, Joint Nature Conservation Committee64, The Evergreen State College65, Estonian University of Life Sciences66, University of Maine67, Virginia Commonwealth University68, Trinity College, Dublin69, University of Auckland70
TL;DR: The first register of the marine species of the world is compiled and it is estimated that between one-third and two-thirds of marine species may be undescribed, and previous estimates of there being well over one million marine species appear highly unlikely.

822 citations


Journal ArticleDOI
24 May 2012-Nature
TL;DR: In this paper, the authors compared phenology (the timing of recurring life history events) in observational studies and warming experiments spanning four continents and 1,634 plant species using a common measure of temperature sensitivity (change in days per degree Celsius).
Abstract: Warming experiments are increasingly relied on to estimate plant responses to global climate change. For experiments to provide meaningful predictions of future responses, they should reflect the empirical record of responses to temperature variability and recent warming, including advances in the timing of flowering and leafing. We compared phenology (the timing of recurring life history events) in observational studies and warming experiments spanning four continents and 1,634 plant species using a common measure of temperature sensitivity (change in days per degree Celsius). We show that warming experiments underpredict advances in the timing of flowering and leafing by 8.5-fold and 4.0-fold, respectively, compared with long-term observations. For species that were common to both study types, the experimental results did not match the observational data in sign or magnitude. The observational data also showed that species that flower earliest in the spring have the highest temperature sensitivities, but this trend was not reflected in the experimental data. These significant mismatches seem to be unrelated to the study length or to the degree of manipulated warming in experiments. The discrepancy between experiments and observations, however, could arise from complex interactions among multiple drivers in the observational data, or it could arise from remediable artefacts in the experiments that result in lower irradiance and drier soils, thus dampening the phenological responses to manipulated warming. Our results introduce uncertainty into ecosystem models that are informed solely by experiments and suggest that responses to climate change that are predicted using such models should be re-evaluated.

751 citations


Journal ArticleDOI
TL;DR: This tutorial review seeks to draw an all-important distinction between artificial molecular switches which are now ten a penny-or a dime a dozen-in the chemical literature and artificial molecular machines which are few and far between despite the ubiquitous presence of their naturally occurring counterparts in living systems.
Abstract: The development and fabrication of mechanical devices powered by artificial molecular machines is one of the contemporary goals of nanoscience. Before this goal can be realized, however, we must learn how to control the coupling/uncoupling to the environment of individual switchable molecules, and also how to integrate these bistable molecules into organized, hierarchical assemblies that can perform significant work on their immediate environment at nano-, micro- and macroscopic levels. In this tutorial review, we seek to draw an all-important distinction between artificial molecular switches which are now ten a penny—or a dime a dozen—in the chemical literature and artificial molecular machines which are few and far between despite the ubiquitous presence of their naturally occurring counterparts in living systems. At the single molecule level, a prevailing perspective as to how machine-like characteristics may be achieved focuses on harnessing, rather than competing with, the ineluctable effects of thermal noise. At the macroscopic level, one of the major challenges inherent to the construction of machine-like assemblies lies in our ability to control the spatial ordering of switchable molecules—e.g., into linear chains and then into muscle-like bundles—and to influence the cross-talk between their switching kinetics. In this regard, situations where all the bistable molecules switch synchronously appear desirable for maximizing mechanical power generated. On the other hand, when the bistable molecules switch “out of phase,” the assemblies could develop intricate spatial or spatiotemporal patterns. Assembling and controlling synergistically artificial molecular machines housed in highly interactive and robust architectural domains heralds a game-changer for chemical synthesis and a defining moment for nanofabrication.

747 citations


Journal ArticleDOI
06 Jul 2012-Science
TL;DR: It is shown that the initial stratification and resulting bloom are instead caused by eddy-driven slumping of the basin-scale north-south density gradient, resulting in a patchy bloom beginning 20 to 30 days earlier than would occur by warming.
Abstract: Springtime phytoplankton blooms photosynthetically fix carbon and export it from the surface ocean at globally important rates. These blooms are triggered by increased light exposure of the phytoplankton due to both seasonal light increase and the development of a near-surface vertical density gradient (stratification) that inhibits vertical mixing of the phytoplankton. Classically and in current climate models, that stratification is ascribed to a springtime warming of the sea surface. Here, using observations from the subpolar North Atlantic and a three-dimensional biophysical model, we show that the initial stratification and resulting bloom are instead caused by eddy-driven slumping of the basin-scale north-south density gradient, resulting in a patchy bloom beginning 20 to 30 days earlier than would occur by warming.

408 citations


Journal ArticleDOI
TL;DR: In this article, four methods were examined to dry cellulose nanocrystal and nanofibrillated cellulose suspensions: (1) oven drying, (2) freeze drying (FD), (3) supercritical drying (SCD), and (4) spray-drying (SD).
Abstract: Increasing research activity on cellulose nanofibril-based materials provides great opportunities for novel, scalable manufacturing approaches. Cellulose nanofibrils (CNFs) are typically processed as aqueous suspensions because of their hydrophilic nature. One of the major manufacturing challenges is to obtain dry CNFs while maintaining their nano-scale dimensions. Four methods were examined to dry cellulose nanocrystal and nanofibrillated cellulose suspensions: (1) oven drying, (2) freeze drying (FD), (3) supercritical drying (SCD), and (4) spray-drying (SD). The particle size and morphology of the CNFs were determined via dynamic light scattering, transmission electron microscopy, scanning electron microscopy, and morphological analysis. SCD preserved the nano-scale dimensions of the cellulose nanofibrils. FD formed ribbon-like structures of the CNFs with nano-scale thicknesses. Width and length were observed in tens to hundreds of microns. SD formed particles with a size distribution ranging from nanometer to several microns. Spray-drying is proposed as a technically suitable manufacturing process to dry CNF suspensions.

373 citations


Journal ArticleDOI
TL;DR: A first synthesis of what the written records and multiple natural archives (multi-proxy data) indicate about climate change and variability across western Eurasia from c. 100 B.C. to 800 A.D. as discussed by the authors confirms that the Roman Empire rose during a period of stable and favorable climatic conditions, which deteriorated during the Empire's third-century crisis.
Abstract: Growing scientific evidence from modern climate science is loaded with implications for the environmental history of the Roman Empire and its successor societies. The written and archaeological evidence, although richer than commonly realized, is unevenly distributed over time and space. A first synthesis of what the written records and multiple natural archives (multi-proxy data) indicate about climate change and variability across western Eurasia from c. 100 B.C. to 800 A.D. confirms that the Roman Empire rose during a period of stable and favorable climatic conditions, which deteriorated during the Empire's third-century crisis. A second, briefer period of favorable conditions coincided with the Empire's recovery in the fourth century; regional differences in climate conditions parallel the diverging fates of the eastern and western Empires in subsequent centuries. Climate conditions beyond the Empire's boundaries also played an important role by affecting food production in the Nile valley, and by encouraging two major migrations and invasions of pastoral peoples from Central Asia.

357 citations


01 Jan 2012
TL;DR: In this article, the authors present an update of the "key points" from the Antarctic Climate Change and the Environment (ACCE) report that was published by the Scientific Committee on Antarctic Research (SCAR) in 2009.
Abstract: We present an update of the ‘key points’ from the Antarctic Climate Change and the Environment (ACCE) report that was published by the Scientific Committee on Antarctic Research (SCAR) in 2009. We summarise subsequent advances in knowledge concerning how the climates of the Antarctic and Southern Ocean have changed in the past, how they might change in the future, and examine the associated impacts on the marine and terrestrial biota. We also incorporate relevant material presented by SCAR to the Antarctic Treaty Consultative Meetings, and make use of emerging results that will form part of the Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report

324 citations


Journal ArticleDOI
TL;DR: Why and how supervisory authority, gender nonconformity, and workplace sex ratios affect harassment are analyzed to delineate why and how female supervisors are more likely to report harassing behaviors and to define their experiences as sexual harassment.
Abstract: Power is at the core of feminist theories of sexual harassment, although it has rarely been measured directly in terms of workplace authority. Popular characterizations portray male supervisors harassing female subordinates, but power-threat theories suggest that women in authority may be more frequent targets. This article analyzes longitudinal survey data and qualitative interviews from the Youth Development Study to test this idea and to delineate why and how supervisory authority, gender nonconformity, and workplace sex ratios affect harassment. Relative to nonsupervisors, female supervisors are more likely to report harassing behaviors and to define their experiences as sexual harassment. Sexual harassment can serve as an equalizer against women in power, motivated more by control and domination than by sexual desire. Interviews point to social isolation as a mechanism linking harassment to gender nonconformity and women's authority, particularly in male-dominated work settings.

322 citations


Journal ArticleDOI
TL;DR: A review of the literature on inquiry-based teaching and learning and science teacher professional development (PD) can be found in this paper, where the authors present a targeted critical review of research focused specifically on the nature of PD programs that emphasize inquiry.
Abstract: This review brings together the literature on inquiry-based teaching and learning and science teacher professional development (PD). We present a targeted critical review of research focused specifically on the nature of PD programs purported to emphasize inquiry. Our review analyzes the features of each program and critiques the reported outcomes of each study. Findings from this review suggest a general alignment with recommended features of effective PD as outlined in the literature with a few notable exceptions, including: supporting teachers in developing inquiry-based lesson plans, providing authentic inquiry experiences, and focusing on science content for teachers. More importantly, our review reveals that no reported study has connected participation in inquiry-based PD with all the desired outcomes of teacher PD: enhanced teacher knowledge, change in beliefs and practice, and enhanced student achievement. Implications for future research on inquiry-based PD programs are discussed.

261 citations


Journal ArticleDOI
TL;DR: The finding that Bd is capable of sexual reproduction between panzootic and endemic genotypes emphasizes the risk of international wildlife trade as a source of additional Bd epizootics owing to hybridization.
Abstract: Global amphibian declines are linked with the presence of specific, highly virulent genotypes of the emerging fungal disease chytridiomycosis caused by Batrachochytrium dendrobatidis (Bd) known as the global panzootic lineage (Bd-GPL). The global trade in amphibians for human consumption is suspected to have facilitated emergence of the disease, but evidence to support this is largely lacking. Here, we investigated the role the Lithobates catesbeianus (North American bullfrog) trade in spreading Bd genotypes by comparing strains associated with L. catesbeianus to a global panel using 36 sequenced loci from multiple chromosomal regions. Most bullfrogs were infected with Bd-GPL genotypes, but we also detected novel, highly divergent Bd genotypes (Bd-Brazil) from a live bullfrog in a US market and from native Brazilian anurans in the Atlantic Forest where bullfrogs are widely farmed. Sexual reproduction was also detected for the first time in Bd in the form of a hybrid genotype between the Bd-GPL and Bd-Brazil lineages in the Atlantic Forest. Despite the demonstration that ribosomal RNA types in Bd fail to undergo concerted evolution (over 20 sequence types may be found in a single strain), the Bd-GPL and Bd-Brazil lineages form largely separate clusters of related internal transcribed spacer (ITS) RNA sequences. Using ITS sequences, we then demonstrate the presence of Bd-Brazil in Japan, primarily on invasive L. catesbeianus. The finding that Bd is capable of sexual reproduction between panzootic and endemic genotypes emphasizes the risk of international wildlife trade as a source of additional Bd epizootics owing to hybridization.

Journal ArticleDOI
TL;DR: This study is the first to experimentally demonstrate a positive relationship between Km and temperature for soil enzymes, suggesting that increasing temperatures and N availability in forests of the northeastern US will lead to increased hydrolytic enzyme activity, despite the positive temperature sensitivity of Km.
Abstract: Soil microbes produce extracellular enzymes that degrade carbon (C)-containing polymers in soil organic matter. Because extracellular enzyme activities may be sensitive to both increased nitrogen (N) and temperature change, we measured the effect of long-term N addition and short-term temperature variation on enzyme kinetics in soils from hardwood forests at Bear Brook, Maine, and Fernow Forest, West Virginia. We determined the Vmax and Km parameters for five hydrolytic enzymes: a-glucosidase, b-glucosidase, b-xylosidase, cellobiohydrolase, and N-acetyl-glucosaminidase. Temperature sensitivities of Vmax and Km were assessed within soil samples subjected to a range of temperatures. We hypothesized that (1) N additions would cause microbial C limitation, leading to higher enzyme Vmax values and lower Km values; and (2) both Vmax and Km would increase at higher temperatures. Finally, we tested whether or not temperature sensitivity of enzyme kinetics is mediated by N addition. Nitrogen addition significantly or marginally significantly increased Vmax values for all enzymes, particularly at Fernow. Nitrogen fertilization led to significantly lower Km values for all enzymes at Bear Brook, but variable Km responses at Fernow Forest. Both Vmax and Km were temperature sensitive, with Q10 values ranging from 1.64–2.27 for enzyme Vmax and 1.04–1.93 for enzyme Km. No enzyme showed a significant interaction between N and temperature sensitivity for Vmax, and only b-xylosidase showed a significant interaction between N and temperature sensitivity for Km. Our study is the first to experimentally demonstrate a positive relationship between Km and temperature for soil enzymes. Higher temperature sensitivities for Vmax relative to Km imply that substrate degradation will increase with temperature. In addition, the Vmax and Km responses to N indicate greater substrate degradation under N addition. Our results suggest that increasing temperatures and N availability in forests of the northeastern US will lead to increased hydrolytic enzyme activity, despite the positive temperature sensitivity of Km.

Journal ArticleDOI
TL;DR: Evidence is presented for important ecological effects associated with human‐induced trait change in a variety of study systems that can occur over large spatial scales and impact system‐wide processes such as trophic cascades.
Abstract: Human-induced trait change has been documented in freshwater, marine, and terrestrial ecosystems worldwide. These trait changes are driven by phenotypic plasticity and contemporary evolution. While efforts to manage human-induced trait change are beginning to receive some attention, managing its ecological consequences has received virtually none. Recent work suggests that contemporary trait change can have important effects on the dynamics of populations, communities, and ecosystems. Therefore, trait changes caused by human activity may be shaping ecological dynamics on a global scale. We present evidence for important ecological effects associated with human-induced trait change in a variety of study systems. These effects can occur over large spatial scales and impact system-wide processes such as trophic cascades. Importantly, the magnitude of these effects can be on par with those of traditional ecological drivers such as species presence. However, phenotypic change is not always an agent of ecological change; it can also buffer ecosystems against change. Determining the conditions under which phenotypic change may promote vs prevent ecological change should be a top research priority.

Journal ArticleDOI
TL;DR: In this paper, the authors synthesize interactions of critical feedbacks of the degraded states from six globally distinct biomes: coral reefs, kelp forests, seagrass beds, shallow soft sediments, oyster reefs, and coastal pelagic food webs.
Abstract: In many coastal areas, marine ecosystems have shifted into contrasting states having reduced ecosystem services (hereafter called degraded). Such degraded ecosystems may be slow to revert to their original state due to new ecological feedbacks that reinforce the degraded state. A better understanding of the way human actions influence the strength and direction of feedbacks, how different feedbacks could interact, and at what scales they operate, may be necessary in some cases for successful management of marine ecosystems. Here we synthesize interactions of critical feedbacks of the degraded states from six globally distinct biomes: coral reefs, kelp forests, seagrass beds, shallow soft sediments, oyster reefs, and coastal pelagic food webs. We explore to what extent current management captures these feedbacks and propose strategies for how and when (that is, windows of opportunity) to influence feedbacks in ways to break the resilience of the degraded ecosystem states. We conclude by proposing some challenges for future research that could improve our understanding of these issues and emphasize that management of degraded marine states will require a broad social–ecological approach to succeed.

Journal ArticleDOI
01 Aug 2012-Ecology
TL;DR: A meta-analysis of studies at 48 sites across four continents that used enriched 15N isotope tracers concluded that growth enhancement and potential for increased C storage in aboveground biomass from atmospheric N deposition is likely to be modest in these ecosystems.
Abstract: Effects of anthropogenic nitrogen (N) deposition and the ability of terrestrial ecosystems to store carbon (C) depend in part on the amount of N retained in the system and its partitioning among plant and soil pools. We conducted a meta-analysis of studies at 48 sites across four continents that used enriched 15N isotope tracers in order to synthesize information about total ecosystem N retention (i.e., total ecosystem 15N recovery in plant and soil pools) across natural systems and N partitioning among ecosystem pools. The greatest recoveries of ecosystem 15N tracer occurred in shrublands (mean, 89.5%) and wetlands (84.8%) followed by forests (74.9%) and grasslands (51.8%). In the short term (< 1 week after 15N tracer application), total ecosystem 15N recovery was negatively correlated with fine-root and soil 15N natural abundance, and organic soil C and N concentration but was positively correlated with mean annual temperature and mineral soil C:N. In the longer term (3-18 months after 15N tracer application), total ecosystem 15N retention was negatively correlated with foliar natural-abundance 15N but was positively correlated with mineral soil C and N concentration and C:N, showing that plant and soil natural-abundance 15N and soil C:N are good indicators of total ecosystem N retention. Foliar N concentration was not significantly related to ecosystem 15N tracer recovery, suggesting that plant N status is not a good predictor of total ecosystem N retention. Because the largest ecosystem sinks for 15N tracer were below ground in forests, shrublands, and grasslands, we conclude that growth enhancement and potential for increased C storage in aboveground biomass from atmospheric N deposition is likely to be modest in these ecosystems. Total ecosystem 15N recovery decreased with N fertilization, with an apparent threshold fertilization rate of 46 kg N x ha(-1) x yr(-1) above which most ecosystems showed net losses of applied 15N tracer in response to N fertilizer addition.

Journal ArticleDOI
TL;DR: In this paper, a rapid, non-destructive approach to carbonate budget assessments, termed ReefBudget that is census-based and which focuses on quantifying the relative contributions made by different biological carbonate producer/eroder groups to net reef framework carbonate production is presented.
Abstract: Census-based approaches can provide important measures of the ecological processes controlling reef carbonate production states. Here, we describe a rapid, non-destructive approach to carbonate budget assessments, termed ReefBudget that is census-based and which focuses on quantifying the relative contributions made by different biological carbonate producer/eroder groups to net reef framework carbonate production. The methodology is presently designed only for Caribbean sites, but has potential to be adapted for use in other regions. Rates are calculated using data on organism cover and abundance, combined with annual extension or production rate measures. Set against this are estimates of the rates at which bioeroding species of fish, urchins and internal substrate borers erode reef framework. Resultant data provide a measure of net rates of biologically driven carbonate production (kg CaCO3 m−2 year−1). These data have potential to be integrated into ecological assessments of reef state, to aid monitoring of temporal (same-site) changes in rates of biological carbonate production and to provide insights into the key ecological drivers of reef growth or erosion as a function of environmental change. Individual aspects of the budget methodology can also be used alongside other census approaches if deemed appropriate for specific study aims. Furthermore, the methodology spreadsheets are user-changeable, allowing local or new process/rate data to be integrated into calculations. Application of the methodology is considered at sites around Bonaire. Highest net rates of carbonate production, +9.52 to +2.30 kg CaCO3 m−2 year−1, were calculated at leeward sites, whilst lower rates, +0.98 to −0.98 kg CaCO3 m−2 year−1, were calculated at windward sites. Data are within the ranges calculated in previous budget studies and provide confidence in the production estimates the methodology generates.

Journal ArticleDOI
12 Dec 2012-PLOS ONE
TL;DR: These studies reveal that human microbiome data has been preserved in some coprolites, and these preserved human microbiomes match more closely to Those from the rural communities than to those from cosmopolitan communities, suggesting that the modern cosmopolitan lifestyle resulted in a dramatic change to the human gut microbiome.
Abstract: In an effort to better understand the ancestral state of the human distal gut microbiome, we examine feces retrieved from archaeological contexts (coprolites). To accomplish this, we pyrosequenced the 16S rDNA V3 region from duplicate coprolite samples recovered from three archaeological sites, each representing a different depositional environment: Hinds Cave (~8000 years B.P.) in the southern United States, Caserones (1600 years B.P.) in northern Chile, and Rio Zape in northern Mexico (1400 years B.P.). Clustering algorithms grouped samples from the same site. Phyletic representation was more similar within sites than between them. A Bayesian approach to source-tracking was used to compare the coprolite data to published data from known sources that include, soil, compost, human gut from rural African children, human gut, oral and skin from US cosmopolitan adults and non-human primate gut. The data from the Hinds Cave samples largely represented unknown sources. The Caserones samples, retrieved directly from natural mummies, matched compost in high proportion. A substantial and robust proportion of Rio Zape data was predicted to match the gut microbiome found in traditional rural communities, with more minor matches to other sources. One of the Rio Zape samples had taxonomic representation consistent with a child. To provide an idealized scenario for sample preservation, we also applied source tracking to previously published data for Otzi the Iceman and a soldier frozen for 93 years on a glacier. Overall these studies reveal that human microbiome data has been preserved in some coprolites, and these preserved human microbiomes match more closely to those from the rural communities than to those from cosmopolitan communities. These results suggest that the modern cosmopolitan lifestyle resulted in a dramatic change to the human gut microbiome.

Journal ArticleDOI
TL;DR: In this paper, the authors estimate a model of urban productivity in which the agglomeration effect of density is enhanced by a metropolitan area's stock of human capital, and demonstrate that the elasticity of average labor productivity with respect to density increases with human capital.
Abstract: We estimate a model of urban productivity in which the agglomeration effect of density is enhanced by a metropolitan area's stock of human capital. Estimation accounts for potential biases due to the endogeneity of density and industrial composition effects. Using new information on output per worker for U.S. metropolitan areas along with a measure of density that accounts for the spatial distribution of population, we find that a doubling of density increases productivity by 2–4 percent. Consistent with theories of learning and knowledge spillovers in cities, we demonstrate that the elasticity of average labor productivity with respect to density increases with human capital. Metropolitan areas with a human capital stock one standard deviation below the mean realize no productivity gain, while doubling density in metropolitan areas with a human capital stock one standard deviation above the mean yields productivity benefits that are about twice the average. These patterns are particularly pronounced in industries where the exchange of information and sharing of ideas are important parts of the production process.

Journal ArticleDOI
TL;DR: In this paper, a numerical method based on a two-phase level set with the global mass correction and immersed boundary method is developed to simulate wave interaction with a semi-submerged chamber.

Journal ArticleDOI
TL;DR: In this article, a large data set consisting of >300 POC samples and simultaneously measured particulate organic carbon (POC) coefficients and attenuation coefficients was used for estimating POC on spatial and temporal scales that are impossible to obtain with traditional sampling and chemical analysis methods.
Abstract: [1] The co-variability of particulate backscattering (bbp) and attenuation (cp) coefficients and particulate organic carbon (POC) provides a basis for estimating POC on spatial and temporal scales that are impossible to obtain with traditional sampling and chemical analysis methods. However, the use of optical proxies for POC in the open ocean is complicated by variable relationships reported in the literature between POC and cp or bbp. During the 2008 North Atlantic Bloom experiment, we accrued a large data set consisting of >300 POC samples and simultaneously measured cp and bbp. Attention to sampling detail, use of multiple types of POC blanks, cross-calibration of optical instruments, and parallel measurements of other biogeochemical parameters facilitated distinction between natural and methodological-based variability. The POC versuscp slope varied with plankton community composition but not depth; slopes were 11% lower for the diatom versus the recycling community. Analysis of literature POC versus cp slopes indicates that plankton composition is responsible for a large component of that variability. The POC versus bbp slope decreased below the pycnocline by 20%, likely due to changing particle composition associated with remineralization and fewer organic rich particles. The higher bbp/cp ratios below the mixed layer are also indicative of particles of lower organic density. We also observed a peculiar platform effect that resulted in ∼27% higher values for downcast versus upcast bbp measurements. Reduction in uncertainties and improvement of accuracies of POC retrieved from optical measurements is important for autonomous sampling, and requires community consensus for standard protocols for optics and POC.

Journal ArticleDOI
TL;DR: Literacy instruction for students with significant intellectual disabilities traditionally emphasizes isolated skills instruction focusing on sight words and basic vocabulary as discussed by the authors, but the LBD approach emphasizes reading for meaning, combining UDL-scaffolded e-books and letter and word recognition software.
Abstract: Literacy instruction for students with significant intellectual disabilities traditionally emphasizes isolated skills instruction focusing on sight words and basic vocabulary. Recent research suggests these students benefit from high-quality instruction that includes comprehension and storybook reading. This study examined the effect of a technology-based universal design for learning (UDL) approach to literacy instruction, Literacy by Design (LBD), on the reading achievement of 16 students with significant intellectual disabilities in Grades K–2. The LBD approach emphasizes reading for meaning, combining UDL-scaffolded e-books and letter and word recognition software. Nine teachers received training in research-based literacy practices. Of these, five received LBD training and implemented it four to five times weekly. Controlling for initial reading achievement, the LBD group made significantly greater gains on the Woodcock–Johnson Test of Achievement III Passage Comprehension subtest. Implications for research and practice in beginning reading instruction for children with significant intellectual disabilities are discussed.

Journal ArticleDOI
TL;DR: Findings are consistent with previous research on the simultaneous use of methadone and benzodiazepines during pregnancy and provide further direction for the treatment of opioid dependency during pregnancy.
Abstract: Objective To examine opioid replacement therapy in pregnancy and effect on neonatal outcomes, including length of hospital stay for neonatal abstinence syndrome. Design Retrospective descriptive study. Setting Labor and delivery unit and neonatal intensive care unit (NICU), Eastern Maine Medical Center, Bangor, Maine. Participants One hundred fifty‐two opioid‐dependent pregnant women on methadone maintenance therapy (MMT) ( n = 136) or buprenorphine maintenance therapy (BMT) ( n = 16) during pregnancy and their neonates. The neonates were born between January 1, 2005 and December 31, 2007. Methods A review of the electronic medical record (EMR) was conducted of all opioid‐dependent women who were maintained on MMT or BMT at the time of admission for labor and delivery and their neonates. Results Maternal methadone dose and concomitant in‐utero exposure to benzodiazepines prolonged the length of hospital stay for neonates. Length of stay was shorter in breastfed neonates than formula‐fed neonates or neonates who received formula and breast milk. Neonates with prenatal exposure to MMT spent more days in the hospital (21 vs. 14 days) for treatment of neonatal abstinence syndrome (NAS) than infants with prenatal exposure to BMT. Conclusion These findings are consistent with previous research on the simultaneous use of methadone and benzodiazepines during pregnancy and provide further direction for the treatment of opioid dependency during pregnancy. Harm reduction strategies for opioid‐dependent pregnant women in substance abuse treatment with MMT may one day include guidance on daily treatment doses and recommendations to avoid the concomitant use of benzodiazepines to lessen NAS. Breastfeeding should be recommended to shorten length of stay. Understanding perinatal and neonatal outcomes of pregnant women on methadone or buprenorphine will help to identify optimal treatment for opioid dependency in pregnancy.

Journal ArticleDOI
01 Oct 2012-Ecology
TL;DR: The diatom-based mixing depth model was applied to sedimentary diatom profiles extending back to 1750 AD in two lakes with moderate nitrate concentrations but differing climate settings, and reconstructions were consistent with expected changes.
Abstract: Over the 20th century, surface water temperatures have increased in many lake ecosystems around the world, but long-term trends in the vertical thermal structure of lakes remain unclear, despite the strong control that thermal stratification exerts on the biological response of lakes to climate change. Here we used both neo- and paleoecological approaches to develop a fossil-based inference model for lake mixing depths and thereby refine understanding of lake thermal structure change. We focused on three common planktonic diatom taxa, the distributions of which previous research suggests might be affected by mixing depth. Comparative lake surveys and growth rate experiments revealed that these species respond to lake thermal structure when nitrogen is sufficient, with species optima ranging from shallower to deeper mixing depths. The diatom-based mixing depth model was applied to sedimentary diatom profiles extending back to 1750 AD in two lakes with moderate nitrate concentrations but differing climate settings. Thermal reconstructions were consistent with expected changes, with shallower mixing depths inferred for an alpine lake where treeline has advanced, and deeper mixing depths inferred for a boreal lake where wind strength has increased. The inference model developed here provides a new tool to expand and refine understanding of climate-induced changes in lake ecosystems.

Journal ArticleDOI
TL;DR: Recognition of the key role played by microscopic reversibility in their operation is a first step towards rational design of artificial molecular devices.
Abstract: Biological motors and pumps are equilibrium devices that couple chemical, electrical and mechanical processes in an environment that is far from equilibrium. Recognition of the key role played by microscopic reversibility in their operation is a first step towards rational design of artificial molecular devices.

Journal ArticleDOI
TL;DR: In this article, an action-based learning approach to promote important pro-environmental actions, such as support for or acceptance of environmental policy, is discussed, which involves promoting simple and easy behaviours as entry points for more radical steps towards sustainability, referred to as "catalytic" or "wedge" behaviours.

Journal ArticleDOI
TL;DR: In this paper, the authors developed a helpfulness hypothesis based on the connection between humility and other prosocial qualities and found that more humble persons were more helpful than less humble persons.
Abstract: Connections between humility and other prosocial qualities led us to develop a humility–helpfulness hypothesis. In three studies, humble persons were more helpful than less humble persons. In Study 1, participants (n = 117) completed self-report measures of humility, the Big Five, and helpfulness. In Study 2, participants (n = 90) completed an implicit measure of humility and were presented with an unexpected opportunity to help someone in need. In Study 3, participants (n = 103) completed self-report and implicit measures of humility and were presented a similar helping opportunity. Humility and helpfulness correlated positively when personality and impression management were controlled. Humble participants helped more than did less humble participants even when agreeableness and desirable responding were statistically controlled. Further, implicit humility uniquely predicted helping behavior in an altruistic motivation condition.

Proceedings Article
01 Dec 2012
TL;DR: Experimental evidence is provided that the approach seems to be able to infer meaningful translation probabilities for phrase pairs not seen in the training data, or even predict a list of the most likely translations given a source phrase.
Abstract: This paper presents a new approach to perform the estimation of the translation model probabilities of a phrase-based statistical machine translation system. We use neural networks to directly learn the translation probability of phrase pairs using continuous representations. The system can be easily trained on the same data used to build standard phrase-based systems. We provide experimental evidence that the approach seems to be able to infer meaningful translation probabilities for phrase pairs not seen in the training data, or even predict a list of the most likely translations given a source phrase. The approach can be used to rescore n-best lists, but we also discuss an integration into the Moses decoder. A preliminary evaluation on the English/French IWSLT task achieved improvements in the BLEU score and a human analysis showed that the new model often chooses semantically better translations. Several extensions of this work are discussed.

Journal ArticleDOI
TL;DR: In this article, a 2000-yr record of Southern Hemisphere volcanism recorded in ice cores from the high accumulation Law Dome site, East Antarctica is presented, with 11 ambiguous years at 23 BCE, the lowest error of all published long Antarc- tic ice cores.
Abstract: Volcanic eruptions are an important cause of nat- ural climate variability. In order to improve the accuracy of climate models, precise dating and magnitude of the climatic effects of past volcanism are necessary. Here we present a 2000-yr record of Southern Hemisphere volcanism recorded in ice cores from the high accumulation Law Dome site, East Antarctica. The ice cores were analysed for a suite of chemistry signals and are independently dated via annual layer counting, with 11 ambiguous years at 23 BCE, which has presently the lowest error of all published long Antarc- tic ice cores. Independently dated records are important to avoid circular dating where volcanic signatures are assigned a date from some external information rather than using the date it is found in the ice core. Forty-five volcanic events have been identified using the sulphate chemistry of the Law Dome record. The low dating error and comparison with the NGRIP (North Greenland Ice Core Project) volcanic records (on the GICC05 timescale) suggest Law Dome is the most accurately dated Antarctic volcanic dataset, which will im- prove the dating of individual volcanic events and potentially allow better correlation between ice core records, leading to improvements in global volcanic forcing datasets. One of the most important volcanic events of the last two millennia is the large 1450s CE event, usually assigned to the eruption of Kuwae, Vanuatu. In this study, we review the evidence sur- rounding the presently accepted date for this event, and make the case that two separate eruptions have caused confusion in the assignment of this event. Volcanic sulphate deposition es- timates are important for modelling the climatic response to eruptions. The largest volcanic sulphate events in our record are dated at 1458 CE (Kuwae?, Vanuatu), 1257 and 422 CE (unidentified).

Journal ArticleDOI
TL;DR: A high degree of pseudo‐cryptic diversity was reported in the well‐studied diatom genus Pseudo‐nitzschia, and two new species, P. hasleana sp.
Abstract: A high degree of pseudo-cryptic diversity was reported in the well-studied diatom genus Pseudo-nitzschia. Studies off the coast of Washington State revealed the presence of hitherto undescribed diversity of Pseudo-nitzschia. Forty-one clonal strains, representing six different taxa of the P. pseudodelicatissima complex, were studied morphologically using LM and EM, and genetically using genes from three different cellular compartments: the nucleus (D1-D3 of the LSU of rDNA and internal transcribed spacers [ITSs] of rDNA), the mitochondria (cytochrome c oxidase 1), and the plastids (LSU of RUBISCO). Strains in culture at the same time were used in mating studies to study reproductive isolation of species, and selected strains were examined for the production of the neurotoxin domoic acid (DA). Two new species, P. hasleana sp. nov. and P. fryxelliana sp. nov., are described based on morphological and molecular data. In all phylogenetic analyses, P. hasleana appeared as sister taxa to a clade comprising P. calliantha and P. mannii, whereas the position of P. fryxelliana was more uncertain. In the phylogenies of ITS, P. fryxelliana appeared to be most closely related to P. cf. turgidula. Morphologically, P. hasleana differed from most other species of the complex because of a lower density of fibulae, whereas P. fryxelliana had fewer sectors in the poroids and a higher poroid density than most of the other species. P. hasleana did not produce detectable levels of DA; P. fryxelliana was unfortunately not tested. In P. cuspidata, production of DA in offspring cultures varied from higher than the parent cultures to undetectable.

Journal ArticleDOI
TL;DR: The objective is to characterize the development of the literature on hypertension and cognitive functioning from a historical perspective and trace and describe the history of this area of research to identify milestones in knowledge and methods.
Abstract: Our objective is to characterize the development of the literature on hypertension and cognitive functioning from a historical perspective. This goal was stimulated by the review on “Historical Trends and Milestones in Hypertension Research” in the October 2012 issue of Hypertension .1 Our specific aims are threefold: (1) to trace and describe the history of this area of research; (2) to identify milestones in knowledge and methods; and (3) to discuss briefly how this literature translates into patient care. The topic is of major relevance to research and practice because hypertension is a well-known risk factor for decline in cognitive performance within the normal range of cognitive functioning, mild cognitive impairment (MCI) and dementia. It is important to emphasize 3 features of the review: (1) it is not designed as a critical review of the literature, but rather to describe the historical influences on our current knowledge base (poor, mediocre and outstanding papers from the past have all shaped our present); (2) word-count limitations require that we omit statistical detail except to emphasize effect sizes in pivotal papers; and (3) each milestone topic is addressed by noting the earliest work then followed by examples of papers representing pivotal events. A number of comprehensive reviews of this literature are available,2–6 including a seminal paper summarizing the formative years of this research.7 Please see http://hyper.ahajournals.org for citations to additional reviews of the literature and papers published in Hypertension . We recognize the importance of the emerging literature on hypotension and cognitive function, but refer the readers to previous reviews which include this topic.8–10 ### Measurement of Cognitive Functioning In this paper, the term cognitive performance is used to describe the outcome of studies measuring a full range of ability from low to high. The term cognitive functioning is used …