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Showing papers by "Université du Québec à Montréal published in 2018"


Journal ArticleDOI
TL;DR: This work proposes two related methods, based on mathematical equations, as alternatives for minimum sample size estimation in PLS‐SEM: the inverse square root method, and the gamma‐exponential method.
Abstract: Partial least squares-based structural equation modelling (PLS-SEM) is extensively used in the field of information systems, as well as in many other fields where multivariate statistical methods are used. One of the most fundamental issues in PLS-SEM is that of minimum sample size estimation. The ‘10-times rule’ has been a favourite because of its simplicity of application, even though it tends to yield imprecise estimates. We propose two related methods, based on mathematical equations, as alternatives for minimum sample size estimation in PLS-SEM: the inverse square root method, and the gamma-exponential method. Based on three Monte Carlo experiments, we demonstrate that both methods are fairly accurate. The inverse square root method is particularly attractive in terms of its simplicity of application. © 2016 John Wiley & Sons Ltd

705 citations


Journal ArticleDOI
13 Feb 2018-PeerJ
TL;DR: The citation impact of OA articles is examined, corroborating the so-called open-access citation advantage: accounting for age and discipline, OAarticles receive 18% more citations than average, an effect driven primarily by Green and Hybrid OA.
Abstract: Despite growing interest in Open Access (OA) to scholarly literature, there is an unmet need for large-scale, up-to-date, and reproducible studies assessing the prevalence and characteristics of OA. We address this need using oaDOI, an open online service that determines OA status for 67 million articles. We use three samples, each of 100,000 articles, to investigate OA in three populations: (1) all journal articles assigned a Crossref DOI, (2) recent journal articles indexed in Web of Science, and (3) articles viewed by users of Unpaywall, an open-source browser extension that lets users find OA articles using oaDOI. We estimate that at least 28% of the scholarly literature is OA (19M in total) and that this proportion is growing, driven particularly by growth in Gold and Hybrid. The most recent year analyzed (2015) also has the highest percentage of OA (45%). Because of this growth, and the fact that readers disproportionately access newer articles, we find that Unpaywall users encounter OA quite frequently: 47% of articles they view are OA. Notably, the most common mechanism for OA is not Gold, Green, or Hybrid OA, but rather an under-discussed category we dub Bronze: articles made free-to-read on the publisher website, without an explicit Open license. We also examine the citation impact of OA articles, corroborating the so-called open-access citation advantage: accounting for age and discipline, OA articles receive 18% more citations than average, an effect driven primarily by Green and Hybrid OA. We encourage further research using the free oaDOI service, as a way to inform OA policy and practice.

579 citations


Journal ArticleDOI
TL;DR: Evidence-based clinical practice guidelines for screening, diagnosis and management of sarcopenia from the task force of the International Conference on Sarcopenia and Frailty Research (ICSFR) are presented.
Abstract: Sarcopenia, defined as an age-associated loss of skeletal muscle function and muscle mass, occurs in approximately 6 - 22 % of older adults. This paper presents evidence-based clinical practice guidelines for screening, diagnosis and management of sarcopenia from the task force of the International Conference on Sarcopenia and Frailty Research (ICSFR). To develop the guidelines, we drew upon the best available evidence from two systematic reviews paired with consensus statements by international working groups on sarcopenia. Eight topics were selected for the recommendations: (i) defining sarcopenia; (ii) screening and diagnosis; (iii) physical activity prescription; (iv) protein supplementation; (v) vitamin D supplementation; (vi) anabolic hormone prescription; (vii) medications under development; and (viii) research. The ICSFR task force evaluated the evidence behind each topic including the quality of evidence, the benefitharm balance of treatment, patient preferences/values, and cost-effectiveness. Recommendations were graded as either strong or conditional (weak) as per the GRADE (Grading of Recommendations Assessment, Development and Evaluation) approach. Consensus was achieved via one face-to-face workshop and a modified Delphi process. We make a conditional recommendation for the use of an internationally accepted measurement tool for the diagnosis of sarcopenia including the EWGSOP and FNIH definitions, and advocate for rapid screening using gait speed or the SARC-F. To treat sarcopenia, we strongly recommend the prescription of resistance-based physical activity, and conditionally recommend protein supplementation/a protein-rich diet. No recommendation is given for Vitamin D supplementation or for anabolic hormone prescription. There is a lack of robust evidence to assess the strength of other treatment options.

466 citations


Journal ArticleDOI
Kara Nerenberg1, Kelly B. Zarnke1, Alexander A. Leung1, Kaberi Dasgupta2, Sonia Butalia3, Kerry McBrien1, Kevin C. Harris4, Meranda Nakhla2, Lyne Cloutier5, Mark Gelfer4, Maxime Lamarre-Cliche6, Alain Milot7, Peter Bolli8, Guy Tremblay, Donna McLean9, Raj Padwal10, Karen C. Tran4, Steven A. Grover11, Simon W. Rabkin4, Gordon W. Moe12, Jonathan G. Howlett1, Patrice Lindsay13, Michael D. Hill1, Mike Sharma14, Thalia S. Field4, Theodore Wein15, Ashkan Shoamanesh14, George K. Dresser16, Pavel Hamet6, Robert J. Herman1, Ellen Burgess1, Steven E. Gryn16, Jean Grégoire17, Richard Lewanczuk10, Luc Poirier, Tavis S. Campbell1, Ross D. Feldman18, Kim L. Lavoie19, Ross T. Tsuyuki10, George Honos6, Ally P.H. Prebtani8, Gregory A. Kline1, Ernesto L. Schiffrin11, Andrew C. Don-Wauchope8, Sheldon W. Tobe20, Richard E. Gilbert21, Lawrence A. Leiter21, Charlotte Jones, Vincent Woo22, Robert A. Hegele16, Peter Selby23, Andrew L. Pipe24, Philip A. McFarlane12, Paul Oh25, Milan Gupta8, Simon L. Bacon26, Janusz Kaczorowski6, Luc Trudeau11, Norman R.C. Campbell1, Swapnil Hiremath27, Michael Roerecke23, JoAnne Arcand28, Marcel Ruzicka24, G. V. Ramesh Prasad12, Michel Vallée29, Cedric Edwards24, Praveena Sivapalan30, S. Brian Penner22, Anne Fournier31, Geneviève Benoit31, Janusz Feber32, Janis M. Dionne4, Laura A. Magee33, Alexander G. Logan34, Anne-Marie Côté35, Evelyne Rey6, Tabassum Firoz36, Laura M. Kuyper4, Jonathan Y. Gabor37, Raymond R. Townsend38, Doreen M. Rabi3, Doreen M. Rabi1, Stella S. Daskalopoulou11 
TL;DR: All individuals with hypertension should have an assessment of global cardiovascular risk to promote health behaviours that lower blood pressure, and an angiotensin receptor-neprilysin inhibitor combination should be used in place of either an ang Elliotensin-converting enzyme inhibitor or angiotENSin receptor blocker in individuals with heart failure.

465 citations


Journal ArticleDOI
TL;DR: This study analyzes existing literature on the basis of the definition of the concepts, terminology used, differences, fundamental perspectives, benefits, disadvantages, and finally the similarities and differences of the e-learning, m-learning (mobile learning), and d-learning
Abstract: In the 21st century, the information and communication technology explosion increases the uses of digital devices for many purposes in the world of work and in formal and non-formal education. This...

265 citations


Journal ArticleDOI
TL;DR: It is argued that intercropping, which is the simultaneous production of multiple crops on the same area of land, could play an essential role in this intensification of agriculture, and the first global meta-analysis on the multifaceted benefits of intercrops was carried out, indicating that inter cropping remains beneficial, both under stressful and non-stressful contexts concerning moisture availability.

262 citations


Journal ArticleDOI
Maria Dornelas1, Laura H. Antão2, Laura H. Antão1, Faye Moyes1  +283 moreInstitutions (130)
TL;DR: The BioTIME database contains raw data on species identities and abundances in ecological assemblages through time to enable users to calculate temporal trends in biodiversity within and amongst assemblage using a broad range of metrics.
Abstract: Motivation: The BioTIME database contains raw data on species identities and abundances in ecological assemblages through time. These data enable users to calculate temporal trends in biodiversity within and amongst assemblages using a broad range of metrics. BioTIME is being developed as a community-led open-source database of biodiversity time series. Our goal is to accelerate and facilitate quantitative analysis of temporal patterns of biodiversity in the Anthropocene.Main types of variables included: The database contains 8,777,413 species abundance records, from assemblages consistently sampled for a minimum of 2 years, which need not necessarily be consecutive. In addition, the database contains metadata relating to sampling methodology and contextual information about each record.Spatial location and grain: BioTIME is a global database of 547,161 unique sampling locations spanning the marine, freshwater and terrestrial realms. Grain size varies across datasets from 0.0000000158 km(2) (158 cm(2)) to 100 km(2) (1,000,000,000,000 cm(2)).Time period and grainBio: TIME records span from 1874 to 2016. The minimal temporal grain across all datasets in BioTIME is a year.Major taxa and level of measurement: BioTIME includes data from 44,440 species across the plant and animal kingdoms, ranging from plants, plankton and terrestrial invertebrates to small and large vertebrates.

231 citations


Journal ArticleDOI
TL;DR: The results demonstrated that drought decreased the agronomic traits differently between rice and wheat among varying growth stages, and future droughts could produce lower yields of rice and Wheat when compared to the current drought.
Abstract: Drought has been one of the most important limiting factors for crop production, which deleteriously affects food security worldwide. The main objective of the present study was to quantitatively assess the effect of drought on the agronomic traits (e.g., plant height, biomass, yield, and yield components) of rice and wheat in combination with several moderators (e.g., drought stress intensity, rooting environment, and growth stage) using a meta-analysis study. The database was created from 55 published studies on rice and 60 published studies on wheat. The results demonstrated that drought decreased the agronomic traits differently between rice and wheat among varying growth stages. Wheat and rice yields decreased by 27.5% and 25.4%, respectively. Wheat grown in pots showed greater decreases in agronomic traits than those grown in the field. Rice showed opposite growing patterns when compared to wheat in rooting environments. The effect of drought on rice increased with plant growth and drought had larger detrimental influences during the reproductive phase (e.g., blooming stage, filling stage, and maturity). However, an exception was found in wheat, which had similar decreased performance during the complete growth cycle. Based on these results, future droughts could produce lower yields of rice and wheat when compared to the current drought.

226 citations


Journal ArticleDOI
TL;DR: A novel communication framework to enable CST in DSS systems by employing a power control-based SI mitigation scheme is proposed and a throughput performance analysis of this proposed framework is carried out.
Abstract: Full-duplex (FD) wireless technology enables a radio to transmit and receive on the same frequency band at the same time, and it is considered to be one of the candidate technologies for the fifth generation (5G) and beyond wireless communication systems due to its advantages, including potential doubling of the capacity and increased spectrum utilization efficiency. However, one of the main challenges of FD technology is the mitigation of strong self-interference (SI). Recent advances in different SI cancellation techniques, such as antenna cancellation, analog cancellation, and digital cancellation methods, have led to the feasibility of using FD technology in different wireless applications. Among potential applications, one important application area is dynamic spectrum sharing (DSS) in wireless systems particularly 5G networks, where FD can provide several benefits and possibilities such as concurrent sensing and transmission (CST), concurrent transmission and reception, improved sensing efficiency and secondary throughput, and the mitigation of the hidden terminal problem. In this direction, first, starting with a detailed overview of FD-enabled DSS, we provide a comprehensive survey of recent advances in this domain. We then highlight several potential techniques for enabling FD operation in DSS wireless systems. Subsequently, we propose a novel communication framework to enable CST in DSS systems by employing a power control-based SI mitigation scheme and carry out the throughput performance analysis of this proposed framework. Finally, we discuss some open research issues and future directions with the objective of stimulating future research efforts in the emerging FD-enabled DSS wireless systems.

185 citations


Journal ArticleDOI
TL;DR: A refined definition of POLSs is provided that is applicable to various key levels of variation and facilitating testable predictions, and conceptual refinements of theory and empirical support of the POLS hypothesis are proposed.
Abstract: This introduction to the topical collection on Pace-of-life syndromes: a framework for the adaptive integration of behaviour, physiology, and life history provides an overview of conceptual, theoretical, methodological, and empirical progress in research on pace-of-life syndromes (POLSs) over the last decade. The topical collection has two main goals. First, we briefly describe the history of POLS research and provide a refined definition of POLS that is applicable to various key levels of variation (genetic, individual, population, species). Second, we summarise the main lessons learned from current POLS research included in this topical collection. Based on an assessment of the current state of the theoretical foundations and the empirical support of the POLS hypothesis, we propose (i) conceptual refinements of theory, particularly with respect to the role of ecology in the evolution of (sexual dimorphism in) POLS, and (ii) methodological and statistical approaches to the study of POLS at all major levels of variation. This topical collection further holds (iii) key empirical examples demonstrating how POLS structures may be studied in wild populations of (non)human animals, and (iv) a modelling paper predicting POLS under various ecological conditions. Future POLS research will profit from the development of more explicit theoretical models and stringent empirical tests of model assumptions and predictions, increased focus on how ecology shapes (sex-specific) POLS structures at multiple hierarchical levels, and the usage of appropriate statistical tests and study designs. As an introduction to the topical collection, we summarise current conceptual, theoretical, methodological and empirical progress in research on pace-of-life syndromes (POLSs), a framework for the adaptive integration of behaviour, physiology and life history at multiple hierarchical levels of variation (genetic, individual, population, species). Mixed empirical support of POLSs, particularly at the within-species level, calls for an evaluation and refinement of the hypothesis. We provide a refined definition of POLSs facilitating testable predictions. Future research on POLSs will profit from the development of more explicit theoretical models and stringent empirical tests of model assumptions and predictions, increased focus on how ecology shapes (sex-specific) POLSs structures at multiple hierarchical levels and the usage of appropriate statistical tests and study designs.

181 citations


Journal ArticleDOI
Angela V. Gallego-Sala1, Dan J. Charman1, Simon Brewer2, Susan Page3, I. Colin Prentice4, Pierre Friedlingstein1, Steve Moreton, Matthew J. Amesbury1, David W. Beilman5, Svante Björck6, Tatiana Blyakharchuk7, Christopher Bochicchio8, Robert K. Booth8, Joan Bunbury9, Philip Camill10, Donna Carless1, Rodney A. Chimner, Michael J. Clifford, Elizabeth L. Cressey1, Colin J Courtney-Mustaphi11, Colin J Courtney-Mustaphi12, François De Vleeschouwer13, Rixt de Jong6, Barbara Fiałkiewicz-Kozieł14, Sarah A. Finkelstein15, Michelle Garneau16, Esther Githumbi12, John Hribjlan, James R. Holmquist17, Paul D.M. Hughes18, Chris D. Jones19, Miriam C. Jones20, Edgar Karofeld21, Eric S. Klein22, Ulla Kokfelt6, Atte Korhola23, Terri Lacourse24, Gaël Le Roux13, Mariusz Lamentowicz14, David Large25, Martin Lavoie26, Julie Loisel27, Helen Mackay28, Glen M. MacDonald17, Markku Mäkilä29, Gabriel Magnan16, Rob Marchant12, Katarzyna Marcisz14, Katarzyna Marcisz30, Antonio Martínez Cortizas31, Charly Massa5, Paul Mathijssen23, D. Mauquoy32, Tim Mighall32, Fraser J.G. Mitchell33, Patrick Moss34, Jonathan E. Nichols35, Pirita Oksanen36, Lisa C. Orme37, Lisa C. Orme1, Maara S. Packalen38, Stephen Robinson39, Thomas P. Roland1, Nicole K. Sanderson1, A. Britta K. Sannel40, Noemí Silva-Sánchez31, Natascha Steinberg1, Graeme T. Swindles41, T. Edward Turner42, T. Edward Turner41, Joanna Uglow1, Minna Väliranta23, Simon van Bellen16, Marjolein van der Linden, Bas van Geel43, Guoping Wang44, Zicheng Yu8, Zicheng Yu45, Joana Zaragoza-Castells1, Yan Zhao44 
TL;DR: This article examined the global relationship between peatland carbon accumulation rates during the last millennium and planetary-scale climate space and found a positive relationship between carbon accumulation and cumulative photosynthetically active radiation during the growing season for mid-to high-latitude peatlands in both hemispheres.
Abstract: The carbon sink potential of peatlands depends on the balance of carbon uptake by plants and microbial decomposition The rates of both these processes will increase with warming but it remains unclear which will dominate the global peatland response Here we examine the global relationship between peatland carbon accumulation rates during the last millennium and planetary-scale climate space A positive relationship is found between carbon accumulation and cumulative photosynthetically active radiation during the growing season for mid- to high-latitude peatlands in both hemispheres However, this relationship reverses at lower latitudes, suggesting that carbon accumulation is lower under the warmest climate regimes Projections under Representative Concentration Pathway (RCP)26 and RCP85 scenarios indicate that the present-day global sink will increase slightly until around ad 2100 but decline thereafter Peatlands will remain a carbon sink in the future, but their response to warming switches from a negative to a positive climate feedback (decreased carbon sink with warming) at the end of the twenty-first century

Journal ArticleDOI
TL;DR: In this article, the authors explore the nature of workplace motivation by testing the continuum structure of motivation proposed by self-determination theory through the application of relatively new and advanced methodological techniques and demonstrate the usefulness of the overarching bifactor exploratory structural equation modeling framework in organizational psychology and discuss implications of such models over more traditional confirmatory factor analyses.

Journal ArticleDOI
TL;DR: The current thinking behind deregulation of the AP-1 pathway and its contribution to HTLV-induced cellular transformation is reviewed.
Abstract: Human T-cell leukemia virus type 1 (HTLV-1) is the causative agent of a fatal malignancy known as adult T-cell leukemia (ATL). One way to address the pathology of the disease lies on conducting research with a molecular approach. In addition to the analysis of ATL-relevant signaling pathways, understanding the regulation of important and relevant transcription factors allows researchers to reach this fundamental objective. HTLV-1 encodes for two oncoproteins, Tax and HTLV-1 basic leucine-zipper factor, which play significant roles in the cellular transformation and the activation of the host's immune responses. Activating protein-1 (AP-1) transcription factor has been linked to cancer and neoplastic transformation ever since the first representative members of the Jun and Fos gene family were cloned and shown to be cellular homologs of viral oncogenes. AP-1 is a dimeric transcription factor composed of proteins belonging to the Jun (c-Jun, JunB, and JunD), Fos (c-Fos, FosB, Fra1, and Fra2), and activating transcription factor protein families. Activation of AP-1 transcription factor family by different stimuli, such as inflammatory cytokines, stress inducers, or pathogens, results in innate and adaptive immunity. AP-1 is also involved in various cellular events including differentiation, proliferation, survival, and apoptosis. Deregulated expression of AP-1 transcription factors is implicated in various lymphomas such as classical Hodgkin lymphomas, anaplastic large cell lymphomas, diffuse large B-cell lymphomas, and adult T-cell leukemia. Here, we review the current thinking behind deregulation of the AP-1 pathway and its contribution to HTLV-induced cellular transformation.

Journal ArticleDOI
TL;DR: Key issues, including the complexity of defining disability, the legal situation in Europe and North America concerning disability at work, and barriers and enablers to employment, are discussed and key findings in the existing literature are shown.
Abstract: Due to the expected decline in the working-age population, especially in European countries, people with disabilities are now more often recognized as a valuable resource in the workforce and resea...

Journal ArticleDOI
Hubertus Fischer1, Hubertus Fischer2, Katrin J. Meissner3, Alan C. Mix4, Nerilie J. Abram5, Jacqueline Austermann6, Victor Brovkin7, Emilie Capron8, Emilie Capron9, Daniele Colombaroli, Anne-Laure Daniau10, Kelsey A. Dyez11, Thomas Felis12, Sarah A. Finkelstein13, Samuel L Jaccard1, Samuel L Jaccard2, Erin L McClymont14, Alessio Rovere15, Alessio Rovere12, Johannes Sutter16, Eric W. Wolff6, Stéphane Affolter2, Stéphane Affolter1, Pepijn Johannes Bakker12, Juan Antonio Ballesteros-Cánovas17, Carlo Barbante18, Thibaut Caley10, Anders E. Carlson4, Olga V. Churakova (Sidorova)19, Olga V. Churakova (Sidorova)17, Giuseppe Cortese20, Brian F. Cumming21, Basil A. S. Davis22, Anne de Vernal23, Julien Emile-Geay24, Sherilyn C. Fritz25, Paul Gierz16, Julia Gottschalk1, Julia Gottschalk2, Max D. Holloway8, Fortunat Joos1, Fortunat Joos2, Michal Kucera12, Marie-France Loutre, Daniel J. Lunt26, Katarzyna Marcisz1, Katarzyna Marcisz2, Katarzyna Marcisz27, Jennifer R. Marlon28, Philippe Martinez10, Valérie Masson-Delmotte29, Christoph Nehrbass-Ahles2, Christoph Nehrbass-Ahles1, Bette L. Otto-Bliesner30, Christoph C. Raible2, Christoph C. Raible1, Bjørg Risebrobakken31, Maria Fernanda Sanchez Goñi10, Maria Fernanda Sanchez Goñi32, Jennifer Saleem Arrigo33, Michael Sarnthein34, Jesper Sjolte35, Thomas F. Stocker2, Thomas F. Stocker1, Patricio A. Velasquez Alvárez2, Patricio A. Velasquez Alvárez1, Willy Tinner2, Willy Tinner1, Paul J. Valdes26, Hendrik Vogel2, Hendrik Vogel1, Heinz Wanner2, Qing Yan36, Zicheng Yu37, Zicheng Yu38, Martin Ziegler39, Martin Ziegler40, Liping Zhou41 
TL;DR: In this article, an observation-based synthesis of the understanding of past intervals with temperatures within the range of projected future warming suggests that there is a low risk of runaway greenhouse gas feedbacks for global warming of no more than 2 °C.
Abstract: Over the past 3.5 million years, there have been several intervals when climate conditions were warmer than during the pre-industrial Holocene. Although past intervals of warming were forced differently than future anthropogenic change, such periods can provide insights into potential future climate impacts and ecosystem feedbacks, especially over centennial-to-millennial timescales that are often not covered by climate model simulations. Our observation-based synthesis of the understanding of past intervals with temperatures within the range of projected future warming suggests that there is a low risk of runaway greenhouse gas feedbacks for global warming of no more than 2 °C. However, substantial regional environmental impacts can occur. A global average warming of 1–2 °C with strong polar amplification has, in the past, been accompanied by significant shifts in climate zones and the spatial distribution of land and ocean ecosystems. Sustained warming at this level has also led to substantial reductions of the Greenland and Antarctic ice sheets, with sea-level increases of at least several metres on millennial timescales. Comparison of palaeo observations with climate model results suggests that, due to the lack of certain feedback processes, model-based climate projections may underestimate long-term warming in response to future radiative forcing by as much as a factor of two, and thus may also underestimate centennial-to-millennial-scale sea-level rise.

Journal ArticleDOI
TL;DR: Drought-induced reductions in tree growth were greatest when the droughts occurred during early- season peaks in radial growth, especially for trees growing in the warmest, driest regions, and it is found that future increases in early-season PET may exacerbate these effects, and potentially offset gains in C uptake and storage in ENA owing to other global change factors.
Abstract: Projected changes in temperature and drought regime are likely to reduce carbon (C) storage in forests, thereby amplifying rates of climate change. While such reductions are often presumed to be greatest in semi-arid forests that experience widespread tree mortality, the consequences of drought may also be important in temperate mesic forests of Eastern North America (ENA) if tree growth is significantly curtailed by drought. Investigations of the environmental conditions that determine drought sensitivity are critically needed to accurately predict ecosystem feedbacks to climate change. We matched site factors with the growth responses to drought of 10,753 trees across mesic forests of ENA, representing 24 species and 346 stands, to determine the broad-scale drivers of drought sensitivity for the dominant trees in ENA. Here we show that two factors-the timing of drought, and the atmospheric demand for water (i.e., local potential evapotranspiration; PET)-are stronger drivers of drought sensitivity than soil and stand characteristics. Drought-induced reductions in tree growth were greatest when the droughts occurred during early-season peaks in radial growth, especially for trees growing in the warmest, driest regions (i.e., highest PET). Further, mean species trait values (rooting depth and ψ50 ) were poor predictors of drought sensitivity, as intraspecific variation in sensitivity was equal to or greater than interspecific variation in 17 of 24 species. From a general circulation model ensemble, we find that future increases in early-season PET may exacerbate these effects, and potentially offset gains in C uptake and storage in ENA owing to other global change factors.

Journal ArticleDOI
TL;DR: This paper proposes a simple approach to quantify the reservoir GHG footprint in terms of the net changes in GHG fluxes to the atmosphere induced by damming, that is, ‘what the atmosphere sees.’
Abstract: Freshwater reservoirs are a known source of greenhouse gas (GHG) to the atmosphere, but their quantitative significance is still only loosely con- strained. Although part of this uncertainty can be attributed to the difficulties in measuring highly variable fluxes, it is also the result of a lack of a clear accounting methodology, particularly about what constitutes new emissions and potential new sinks. In this paper, we review the main processes involved in the generation of GHG in reservoir systems and propose a simple approach to quantify the reservoir GHG footprint in terms of the net changes in GHG fluxes to the atmosphere induced by damming, that is, 'what the atmosphere sees.' The approach takes into account the pre-impoundment GHG balance of the landscape, the temporal evolution of reservoir GHG emission profile as well as the natural emissions that are displaced to or away from the reservoir site resulting from hydrological and other changes. It also clarifies the portion of the reservoir carbon burial that can potentially be considered an offset to GHG emissions.

Journal ArticleDOI
TL;DR: The importance of considering known microbial processes to inform the understanding of the role of microbial communities in ecosystem processes is discussed, and a move away from approaches based solely on correlation analyses is discussed.
Abstract: Translating the ever-increasing wealth of information on microbiomes (environment, host or built environment) to advance our understanding of system-level processes is proving to be an exceptional research challenge. One reason for this challenge is that relationships between characteristics of microbiomes and the system-level processes that they influence are often evaluated in the absence of a robust conceptual framework and reported without elucidating the underlying causal mechanisms. The reliance on correlative approaches limits the potential to expand the inference of a single relationship to additional systems and advance the field. We propose that research focused on how microbiomes influence the systems they inhabit should work within a common framework and target known microbial processes that contribute to the system-level processes of interest. Here, we identify three distinct categories of microbiome characteristics (microbial processes, microbial community properties and microbial membership) and propose a framework to empirically link each of these categories to each other and the broader system-level processes that they affect. We posit that it is particularly important to distinguish microbial community properties that can be predicted using constituent taxa (community-aggregated traits) from those properties that cannot currently be predicted using constituent taxa (emergent properties). Existing methods in microbial ecology can be applied to more explicitly elucidate properties within each of these three categories of microbial characteristics and connect them with each other. We view this proposed framework, gleaned from a breadth of research on environmental microbiomes and ecosystem processes, as a promising pathway with the potential to advance discovery and understanding across a broad range of microbiome science.

Journal ArticleDOI
TL;DR: The impact of the recent financial crisis on the relation between a firm’s risk and social performance (SP) using a sample of non-financial U.S. firms covering the period 1991–2012 is examined.
Abstract: This paper examines the impact of the recent financial crisis (2008–2009) on the relation between a firm’s risk and social performance (SP) using a sample of non-financial U.S. firms covering the period 1991–2012. We find that the relation between SP and risk is significantly different in the crisis period (post-crisis period) compared to the pre-crisis period. SP reduces volatility during the financial crisis. The risk reduction potential of SP is mainly due to the strengths component of SP. Since the relation of risk is stronger with SP strengths than SP concerns, this implies an asymmetric relation between these SP components and a firm’s risk. Specifically, strengths act as a risk reduction tool during an adverse economic environment.

Journal ArticleDOI
TL;DR: In this article, a pan-African overview of the effects of 1.5 and 2°C global warming levels (GWLs) on the African climate was presented using a large ensemble of CORDEX Africa simulations.
Abstract: There is a general lack of information about the potential effects of 1.5, 2 or more degrees of global warming on the regional climates within Africa, and most studies that address this use data from coarse resolution global models. Using a large ensemble of CORDEX Africa simulations, we present a pan-African overview of the effects of 1.5 and 2°C global warming levels (GWLs) on the African climate. The CORDEX simulations, consistent with their driving global models, show a robust regional warming exceeding the mean global one over most of Africa. The highest increase in annual mean temperature is found over the subtropics and the smallest one over many coastal regions. Projected changes in annual mean precipitation have a tendency to wetter conditions in some parts of Africa (e.g. central/eastern Sahel and eastern Africa) at both GWLs, but models' agreement on the sign of change is low. In contrast to mean precipitation there is a consistent increase in daily precipitation intensity of wet days over a large fraction of tropical Africa emerging already at 1.5°C GWL and strengthening at 2°C. A consistent difference between 2°C and 1.5°C warmings is also found for projected changes in annual mean temperature and daily precipitation intensity. Our study indicates that a 0.5°C further warming (from 1.5°C to 2°C) can indeed produce a robust change in some aspects of the African climate and its extremes.

Journal ArticleDOI
TL;DR: The results confirm the transitory nature of warming-induced growth benefits in the boreal forest and highlight the vulnerability of the ecosystem to excess warming and drying and predict that growth enhancements may be seen up to 2 °C warming, but would decline if temperatures exceed this.
Abstract: Predicted increases in temperature and aridity across the boreal forest region have the potential to alter timber supply and carbon sequestration. Given the widely-observed variation in species sensitivity to climate, there is an urgent need to develop species-specific predictive models that can account for local conditions. Here, we matched the growth of 270,000 trees across a 761,100 km2 region with detailed site-level data to quantify the growth responses of the seven most common boreal tree species in Eastern Canada to changes in climate. Accounting for spatially-explicit species-specific responses, we find that while 2 °C of warming may increase overall forest productivity by 13 ± 3% (mean ± SE) in the absence of disturbance, additional warming could reverse this trend and lead to substantial declines exacerbated by reductions in water availability. Our results confirm the transitory nature of warming-induced growth benefits in the boreal forest and highlight the vulnerability of the ecosystem to excess warming and drying.

Journal ArticleDOI
18 Sep 2018-eLife
TL;DR: This study established a measurable effect of colonization history on gut microbiota assembly in a model in which host and environmental factors were strictly controlled, illuminating a potential cause for the high levels of unexplained individuality in host-associated microbial communities.
Abstract: The factors that govern assembly of the gut microbiota are insufficiently understood. Here, we test the hypothesis that inter-individual microbiota variation can arise solely from differences in the order and timing by which the gut is colonized early in life. Experiments in which mice were inoculated in sequence either with two complex seed communities or a cocktail of four bacterial strains and a seed community revealed that colonization order influenced both the outcome of community assembly and the ecological success of individual colonizers. Historical contingency and priority effects also occurred in Rag1-/- mice, suggesting that the adaptive immune system is not a major contributor to these processes. In conclusion, this study established a measurable effect of colonization history on gut microbiota assembly in a model in which host and environmental factors were strictly controlled, illuminating a potential cause for the high levels of unexplained individuality in host-associated microbial communities.

Journal ArticleDOI
TL;DR: In this paper, the authors suggest that the problem areas attached to these projects stretch beyond technical issues: they must be considered as socio-technical endeavours embedded in complex institutional frames, and they suggest that studying how to deal with institutional differences in the environment of megaprojects has both theoretical and practical implications.

Journal ArticleDOI
TL;DR: The authors analyzes which specific corporate social responsibility strategies arise in response to competitive pressures, and finds that competitive pressures lead firms to increase their positive social actions without necessarily decreasing their social weaknesses.
Abstract: Is corporate social responsibility (CSR) a tool for strategic positioning? While CSR is sometimes used as part of a differentiation strategy, this article analyzes which specific CSR strategies arise in response to competitive pressures. The results suggest that competitive pressures lead firms to increase their positive social actions without necessarily decreasing their social weaknesses. This positive impact varies with specific dimensions of CSR and industry specificities: (1) Competition improves social performance toward core stakeholders to a greater extent than social performance toward peripheral stakeholders. (2) This effect is more pronounced in B2C industries than in other industries. (3) Competition leads firms in “dirty” industries to ignore environmental initiatives.

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TL;DR: In this article, the amplituhedron can be fully described in binary code: canonical projections of the geometry down to one dimension have a specified (and maximal) number of sign flips of the projected data.
Abstract: We present new, fundamentally combinatorial and topological characterizations of the amplituhedron. Upon projecting external data through the amplituhedron, the resulting configuration of points has a specified (and maximal) generalized “winding number”. Equivalently, the amplituhedron can be fully described in binary: canonical projections of the geometry down to one dimension have a specified (and maximal) number of “sign flips” of the projected data. The locality and unitarity of scattering amplitudes are easily derived as elementary consequences of this binary code. Minimal winding defines a natural “dual” of the amplituhedron. This picture gives us an avatar of the amplituhedron purely in the configuration space of points in vector space (momentum-twistor space in the physics), a new interpretation of the canonical amplituhedron form, and a direct bosonic understanding of the scattering super-amplitude in planar $$ \mathcal{N} $$ = 4 SYM as a differential form on the space of physical kinematical data.

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TL;DR: The results show that the formation of fertile islands in global drylands largely depends on: (1) local climatic, topographic and edaphic characteristics, (2) the structure and traits of local plant communities and (3) soil microbial communities, which has broad implications for the management and restoration of dryland ecosystems worldwide.
Abstract: Dryland vegetation is characterized by discrete plant patches that accumulate and capture soil resources under their canopies. These “fertile islands” are major drivers of dryland ecosystem structure and functioning, yet we lack an integrated understanding of the factors controlling their magnitude and variability at the global scale. We conducted a standardized field survey across 236 drylands from five continents. At each site, we measured the composition, diversity and cover of perennial plants. Fertile island effects were estimated at each site by comparing composite soil samples obtained under the canopy of the dominant plants and in open areas devoid of perennial vegetation. For each sample, we measured 15 soil variables (functions) associated with carbon, nitrogen and phosphorus cycling and used the relative interaction index to quantify the magnitude of the fertile island effect for each function. In 80 sites, we also measured fungal and bacterial abundance (quantitative PCR) and diversity (Illumina MiSeq). The most fertile islands, i.e. those where a higher number of functions were simultaneously enhanced, were found at lower elevation sites with greater soil pH values and sand content under semiarid climates, particularly at locations where the presence of tall woody species with a low-specific leaf area increased fungal abundance beneath plant canopies, the main direct biotic controller of the fertile island effect in the drylands studied. Positive effects of fungal abundance were particularly associated with greater nutrient contents and microbial activity (soil extracellular enzymes) under plant canopies. Synthesis. Our results show that the formation of fertile islands in global drylands largely depends on: (1) local climatic, topographic and edaphic characteristics, (2) the structure and traits of local plant communities and (3) soil microbial communities. Our study also has broad implications for the management and restoration of dryland ecosystems worldwide, where woody plants are commonly used as nurse plants to enhance the establishment and survival of beneficiary species. Finally, our results suggest that forecasted increases in aridity may enhance the formation of fertile islands in drylands worldwide.

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TL;DR: Researchers have compared the recent availability of large-scale behavioral datasets, such as the ones generated by mobile phones, to the invention of the microscope, giving rise to the new field of computational social science.
Abstract: The breadcrumbs we leave behind when using our mobile phones—who somebody calls, for how long, and from where—contain unprecedented insights about us and our societies. Researchers have compared the recent availability of large-scale behavioral datasets, such as the ones generated by mobile phones, to the invention of the microscope, giving rise to the new field of computational social science.

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TL;DR: The pace-of-life syndrome hypothesis is revisited, suggesting that behaviors involving a risk of death or injury should coevolve with higher metabolic rates, higher fecundity, faster growth, and heightened mortality rates.
Abstract: The pace-of-life syndrome (i.e., POLS) hypothesis posits that behavioral and physiological traits mediate the trade-off between current and future reproduction. This hypothesis predicts that life history, behavioral, and physiological traits will covary under clearly defined conditions. Empirical tests are equivocal and suggest that the conditions necessary for the POLS to emerge are not always met. We nuance and expand the POLS hypothesis to consider alternative relationships among behavior, physiology, and life history. These relationships will vary with the nature of predation risk, the challenges posed by resource acquisition, and the energy management strategies of organisms. We also discuss how the plastic response of behavior, physiology, and life history to changes in ecological conditions and variation in resource acquisition among individuals determine our ability to detect a fast-slow pace of life in the first place or associations among these traits. Future empirical studies will provide most insights on the coevolution among behavior, physiology, and life history by investigating these traits both at the genetic and phenotypic levels in varying types of predation regimes and levels of resource abundance. We revisit the pace-of-life syndrome hypothesis, suggesting that behaviors involving a risk of death or injury should coevolve with higher metabolic rates, higher fecundity, faster growth, and heightened mortality rates. Empirical support for this hypothesis is mixed. We show how relaxing some of the assumptions underlying the pace-of-life syndrome hypothesis allows us to consider alternative relationships among behavior, physiology, and life history, and why we fail to meet the predictions posed by the pace-of-life syndrome hypothesis in some populations. Our discussion emphasizes the need to re-integrate the role of the species’ natural history, ecological conditions, and phenotypic plasticity in shaping relationships among behavior, physiology, and life history.

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TL;DR: Using state-of-the-art HARDI tractography algorithm, the subcortical connectivity of the insula is explored by exploring the structural connectivity of insular ROIs with the thalamus, amygdala, hippocampus, putamen, globus pallidus, caudate nucleus and nucleus accumbens.
Abstract: Hidden beneath the Sylvian fissure and sometimes considered as the fifth lobe of the brain, the insula plays a multi-modal role from its strategic location. Previous structural studies have reported cortico-cortical connections with the frontal, temporal, parietal and occipital lobes, but only a few have looked at its connections with subcortical structures. The insular cortex plays a role in a wide range of functions including processing of visceral and somatosensory inputs, olfaction, audition, language, motivation, craving, addiction and emotions such as pain, empathy and disgust. These functions implicate numerous subcortical structures, as suggested by various functional studies. Based on these premises, we explored the structural connectivity of insular ROIs with the thalamus, amygdala, hippocampus, putamen, globus pallidus, caudate nucleus and nucleus accumbens. More precisely, we were interested in unraveling the specific areas of the insula connected to these subcortical structures. By using state-of-the-art HARDI tractography algorithm, we explored here the subcortical connectivity of the insula.

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TL;DR: In this paper, the global N2O Model Intercomparison Project (NMIP) was initialized with 10 state-of-the-art terrestrial biosphere models that include nitrogen cycling.
Abstract: Nitrous oxide (N2O) is an important greenhouse gas and also an ozone-depleting substance that has both natural and anthropogenic sources. Large estimation uncertainty remains on the magnitude and spatiotemporal patterns of N2O fluxes and the key drivers of N2O production in the terrestrial biosphere. Some terrestrial biosphere models have been evolved to account for nitrogen processes and to show the capability to simulate N2O emissions from land ecosystems at the global scale, but large discrepancies exist among their estimates primarily because of inconsistent input datasets, simulation protocol, and model structure and parameterization schemes. Based on the consistent model input data and simulation protocol, the global N2O Model Intercomparison Project (NMIP) was initialized with 10 state-of-the-art terrestrial biosphere models that include nitrogen (N) cycling. Specific objectives of NMIP are to 1) unravel the major N cycling processes controlling N2O fluxes in each model and identify the unc...