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Rhododendron maximum is a native evergreen shrub that has expanded in Appalachian forests following declines of american chestnut (Castanea dentata) and eastern hemlock (Tsuga canadensis). R. maximum is of concern to forest managers because it suppresses hardwood tree establishment by limiting light and soil nutrient availability. We are testing R. maximum removal as a management strategy to promote recovery of Appalachian forests. We hypothesized that R. maximum removal would increase soil nitrogen (N) availability, resulting in increased microbial C-demand (i.e. increased C-acquiring enzyme activity) and a shift towards bacterial-dominated microbial communities. R. maximum removal treatments were applied in a 2 x 2 factorial design, with two R. maximum canopy removal levels (removed vs not) combined with two O-horizon removal levels (burned vs unburned). Following removals, we sampled soils and found that dissolved organic carbon (DOC), N (TDN, NO3, NH4), and microbial biomass all increased with R. maximum canopy + O-horizon removal. Additionally, we observed increases in C-acquisition enzymes involved in degrading cellulose (beta-glucosidase) and hemicellulose (B-xylosidase) with canopy + O-horizon removal. We did not see treatment effects on bacterial dominance, though F:B ratios from all treatments increased from spring to summer. Our results show that R. maximum removal stimulates microbial activity by increasing soil C and N availability, which may influence recovery of forests in the Appalachian region. ; Coweeta LTER - National Science Foundation [DEB-1440485]; Coweeta Hydrologic Laboratory, Southern Research Station, USDA Forest Service ; We thank Bobbie Niederlehner for help with soil chemistry analyses and the VT Stream Team for their helpful comments on this work. This project was supported by the Coweeta LTER, funded by National Science Foundation grant DEB-1440485. We also thank the Coweeta Hydrologic Laboratory, Southern Research Station, USDA Forest Service for support and the USDA Forest Service Nantahala Ranger District staff, Nantahala National Forest, for executing the treatments. Finally, we thank two anonymous reviewers, whose feedback greatly improved this manuscript. The use of trade or firm names in this publication is for reader information and does not imply endorsement by the U.S. Department of Agriculture of any product or service. ; Public domain authored by a U.S. government employee

The EU Carbon-CAP project assembled a comprehensive portfolio of consumer initiatives in order to assess the potential total impact of consumer options on national carbon footprints. Existing evaluations of behavioural change have focused primarily on direct energy reductions, typically in households and buildings. However, changes in consumer demand have deeper impacts via their upstream supply chains. The consumer behaviour options considered in the portfolio focus on green household initiatives. Combining existing micro-level studies with a multiregional input-output economic model, we estimated the potential efficacy and uptake of each behaviour across the European Union (EU). The results suggest that adopting these consumer options could reduce carbon footprints by approximately 25%. While 75% of this is delivered as reductions in emissions within Europe, one-quarter of the effect is delivered as a reduced imported carbon footprint, due to changes in the composition of imports. ; publishedVersion ; © 2018 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

It is expected that biodiesel production in the EU will remain the dominant contributor as part of a 10% minimum binding target for biofuel in transportation fuel by 2020 within the 20% renewable energy target in the overall EU energy mix. Life cycle assessments (LCA) of biodiesel to evaluate its environmental impacts have, however, remained questionable, mainly because of the adoption of a traditional process analysis approach resulting in system boundary truncation and because of issues regarding the impacts of land use change and N2O emissions from fertiliser application. In this study, a hybrid LCA methodology is used to evaluate the life cycle CO2 equivalent emissions of rape methyl ester (RME) biodiesel. The methodology uses input-output analysis to estimate upstream indirect emissions in order to complement traditional process LCA in a hybrid framework. It was estimated that traditional LCA accounted for 2.7 kg CO2-eq per kg of RME or 36.6% of total life cycle emissions of28 the RME supply chin. Further to the inclusion of upstream indirect impacts in the LCA system (which accounted for 23% of the total life cycle emissions), emissions due to direct land use change (6%) and indirect land use change (16.5%) and N2O emissions from fertiliser applications (17.9%) were also calculated. Structural path analysis is used to decompose upstream indirect emissions paths of the biodiesel supply chain in order to identify, quantify and rank high carbon emissions paths or 'hot-spots' in the biodiesel supply chain. It was shown, for instance, that inputs from the 'Other Chemical Products' sector (identified as phosphoric acid, H3PO4) into the biodiesel production process represented the highest carbon emission path (or hot-spot) with 5.35% of total upstream indirect emissions of the RME biodiesel supply chain.

In Appalachian ecosystems, forest disturbance has long-term effects on microbially driven biogeochemical processes such as nitrogen (N) cycling. However, little is known regarding long-term responses of forest soil microbial communities to disturbance in the region. We used 16S and ITS sequencing to characterize soil bacterial (16S) and fungal (ITS) communities across forested watersheds with a range of past disturbance regimes and adjacent reference forests at the Coweeta Hydrologic Laboratory in the Appalachian mountains of North Carolina. Bacterial communities in previously disturbed forests exhibited consistent responses, including increased alpha diversity and increased abundance of copiotrophic (e.g., Proteobacteria) and N-cycling (e.g., Nitrospirae) bacterial phyla. Fungal community composition also showed disturbance effects, particularly in mycorrhizal taxa. However, disturbance did not affect fungal alpha diversity, and disturbance effects were not consistent at the fungal class level. Co-occurrence networks constructed for bacteria and fungi showed that disturbed communities were characterized by more connected and tightly clustered network topologies, indicating that disturbance alters not only community composition but also potential ecological interactions among taxa. Although bacteria and fungi displayed different long-term responses to forest disturbance, our results demonstrate clear responses of important bacterial and fungal functional groups (e.g., nitrifying bacteria and mycorrhizal fungi), and suggest that both microbial groups play key roles in the long-term alterations to biogeochemical processes observed following forest disturbance in the region. ; Coweeta LTER; National Science FoundationNational Science Foundation (NSF) [DEB-1637522] ; This work was funded by the Coweeta LTER, funded by National Science Foundation grant DEB-1637522. ; Public domain authored by a U.S. government employee

OBJECTIVES: Long-term studies of oil spill responders are urgently needed as oil spills continue to occur. To this end, we established the prospective Deepwater Horizon (DWH) Oil Spill Coast Guard Cohort study. METHODS: DWH oil spill responders (n=8696) and non-responders (n=44 823) who were members of the US Coast Guard (20 April–17 December 2010) were included. This cohort uses both prospective, objective health data from military medical encounters and cross-sectional survey data. Here, we describe the cohort, present adjusted prevalence ratios (PRs) estimating cross-sectional associations between crude oil exposure (none, low/medium, high) and acute physical symptoms, and present adjusted relative risks (RRs) based on longitudinal medical encounter data (2010–2012) for responders/non-responders and responders exposed/not exposed to crude oil. RESULTS: Responders and non-responders in this large cohort (n=53 519) have similar characteristics. Crude oil exposure was reported by >50% of responders. We found statistically significant associations for crude oil exposure with coughing (PR(high)=1.78), shortness of breath (PR(high)=2.30), wheezing (PR(high)=2.32), headaches (PR(high)=1.46), light-headedness/dizziness (PR(high)=1.96), skin rash/itching (PR(high)=1.87), diarrhoea (PR(high)=1.76), stomach pain (PR(high)=1.67), nausea/vomiting (PR(high)=1.48) and painful/burning urination (PR(high)=2.89) during deployment. Longitudinal analyses revealed that responders had elevated RRs for dermal conditions (RR=1.09), as did oil-exposed responders for chronic respiratory conditions (RR=1.32), asthma (RR=1.83) and dermal conditions (RR=1.21). CONCLUSIONS: We found positive associations between crude oil exposure and various acute physical symptoms among responders, as well as longer term health effects. This cohort is well positioned to evaluate both short-term and long-term effects of oil spill exposures using both self-reported and clinical health data.

The Signature Series Symposium "Cellular Therapies for Orthopaedics and Musculoskeletal Disease Proven and Unproven Therapies—Promise, Facts and Fantasy" was held as a pre-meeting of the 26(th) International Society for Cellular Therapy (ISCT) annual congress in Montreal, Canada, May 2, 2018. This was the first ISCT program that was entirely dedicated to the advancement of cell-based therapies for musculoskeletal diseases. Cellular therapies in musculoskeletal medicine are a source of great promise and opportunity. They are also the source of public controversy, confusion and misinformation. Patients, clinicians, scientists, industry and government share a commitment to clear communication and responsible development of the field. Therefore, this symposium convened thought leaders from around the world in a forum designed to catalyze communication and collaboration to bring the greatest possible innovation and value to patients with musculoskeletal conditions.

A revealing look at the constitutional issues that confronted and shaped each presidency from Woodrow Wilson through Donald J. TrumpDrawing from the monumental publication The Presidents and the Constitution: A Living History in 2016, the nation's foremost experts in the American presidency and the US Constitution tell the intertwined stories of how the last eighteen American presidents have interfaced with the Constitution and thus defined the most powerful office in human history.This volume leads off with Woodrow Wilson, the president who led the nation through World War I, and ends with Donald J. Trump, who ushered the US into uncharted political and legal territory. In between, the country was confronted with international wars, the civil rights movement, 9/11, and the advent of the internet, all of which presented unique and pressing constitutional issues. The last one hundred years reveals the awesome powers of the American presidency in domestic and foreign affairs, illustrating how they have stood up to modern and novel legal challenges. The Presidents and the Constitution is for anyone interested in a captivating and illuminating account of one of the most compelling subjects in our American democracy

Please read abstract in the article. ; The authors of this Letter thank the following organizations and programs: the Academy of Finland (projects 274477, 284495, 312496); the Advanced European Network of E-infrastructures for Astronomy with the SKA (AENEAS) project, supported by the European Commission Framework Programme Horizon 2020 Research and Innovation action under grant agreement 731016; the Alexander von Humboldt Stiftung; the Black Hole Initiative at Harvard University, through a grant (60477) from the John Templeton Foundation; the China Scholarship Council; Comisión Nacional de Investigación Científica y Tecnológica (CONICYT, Chile, via PIA ACT172033, Fondecyt 1171506, BASAL AFB-170002, ALMA-conicyt 31140007); Consejo Nacional de Ciencia y Tecnología (CONACYT, Mexico, projects 104497, 275201, 279006, 281692); the Delaney Family via the Delaney Family John A. Wheeler Chair at Perimeter Institute; Dirección General de Asuntos del Personal Académico–Universidad Nacional Autónoma de México (DGAPA–UNAM, project IN112417); the European Research Council Synergy Grant "BlackHoleCam: Imaging the Event Horizon of Black Holes" (grant 610058); the Generalitat Valenciana postdoctoral grant APOSTD/2018/177; the Gordon and Betty Moore Foundation (grants GBMF-3561, GBMF-5278); the Istituto Nazionale di Fisica Nucleare (INFN) sezione di Napoli, iniziative specifiche TEONGRAV; the International Max Planck Research School for Astronomy and Astrophysics at the Universities of Bonn and Cologne; the Jansky Fellowship program of the National Radio Astronomy Observatory (NRAO); the Japanese Government (Monbukagakusho: MEXT) Scholarship; the Japan Society for the Promotion of Science (JSPS) Grant-in-Aid for JSPS Research Fellowship (JP17J08829); JSPS Overseas Research Fellowships; the Key Research Program of Frontier Sciences, Chinese Academy of Sciences (CAS, grants QYZDJ-SSWSLH057 QYZDJ-SSW-SYS008); the Leverhulme Trust Early Career Research Fellowship; the Max-Planck-Gesellschaft (MPG); the Max Planck Partner Group of the ...

Frontmatter -- CONTENTS -- THE CONTRIBUTORS -- ACKNOWLEDGEMENTS -- TABLES AND FIGURES -- PREFACE -- 1 INTRODUCTION -- PART 1 ENERGY POLICY DELIVERY IN GENERAL -- 2 SIX MAXIMS FOR INFORMED ENERGY ANALYSIS AND POLICY -- 3 ENDING SUBSIDIES FOR FOSSIL FUEL EXPLORATION IN A WORLD OF UNBURNABLE CARBON -- 4 WERE NORTH SEA OIL AND GAS 'FIELD ALLOWANCES' SUBSIDIES - AND DOES IT MATTER? -- 5 RENEWABLE ENERGY DISPUTES -- 6 USING A LEGACY FRAME TO DELIVER ENERGY AND ENVIRONMENT POLICIES -- 7 THE EMERGENCE OF EU ENERGY LAW -- 8 HOW TO IMPROVE REGULATION -- 9 DELIVERING ENERGY NETWORKS SECURITY: ECONOMICS, REGULATION AND POLICY -- 10 THE ROLE OF MARKETING IN DELIVERING ENERGY LAW AND POLICY -- PART 2 ENERGY POLICY DELIVERY IN THE UNITED STATES -- 11 A BRIEF HISTORY OF US ENERGY POLICY -- 12 APPLYING INNOVATION POLICY TO THE US ENERGY/CLIMATE CHALLENGE -- 13 NATIONAL SCIENTIFIC LABORATORIES AS AN ENERGY POLICY VEHICLE: THE UNITED STATES' EXPERIENCE -- 14 DELIVERING ENERGY POLICY IN THE US: THE ROLE OF TAXES -- 15 DELIVERING THE WIND: DECONSTRUCTING RENEWABLE ENERGY SUCCESS IN TEXAS -- 16 SOLAR RIGHTS IN THE UNITED STATES -- 17 THE US-CHINA CLIMATE AGREEMENT: A NEW DIRECTION -- 18 GOING GREEN: THE UNITED STATES DEPARTMENT OF DEFENSE AND ENERGY SECURITY -- 19 US CONJUNCTIVE WATER MANAGEMENT AND SUSTAINABLE ENERGY DEVELOPMENT -- PART 3 ENERGY POLICY DELIVERY IN THE EUROPEAN UNION -- 20 DELIVERING NEW POLITY: PAVING THE WAY FOR THE EUROPEAN ENERGY UNION -- 21 ANTITRUST ENFORCEMENT IN THE EU ENERGY SECTOR -- 22 DELIVERING ENERGY POLICY IN THE EU: SOME THOUGHTS ON THE ROLE OF CONSUMERS -- 23 THE GROWING IMPACT OF FREE MOVEMENT PROVISIONS IN THE EU ENERGY MARKET -- 24 ENERGY, EXTERNALITIES AND THE NEED TO REVISIT DEUTSCHE BAHN: A PROPOSAL TO REVERSE THE EUROPEAN STANCE ON EU STATE AID LAW AND INTERNATIONAL AVIATION -- 25 RES: TOWARDS A NEW EUROPEAN POLICY -- 26 ENERGIEWENDE IN GERMANY: THE DAWN OF A NEW ENERGY ERA -- 27 WHAT IS A SUSTAINABLE POLICY? A CASE FOR THE ENERGIEWENDE -- 28 THE FINNISH ENERGY POLICY: FULFILLING THE EU ENERGY AND CLIMATE TARGETS WITH NUCLEAR AND RENEWABLES -- 29 THE EU-RUSSIA RELATIONSHIP AND THE EU ENERGY UNION: FROM DEPENDENCE AND VULNERABILITY TOWARDS COMPETITION AND A FREE FLOW -- PART 4 ELECTRICITY POLICY DELIVERY -- 30 THE ROLE OF UNCERTAINTY IN ENERGY INVESTMENTS AND REGULATION -- 31 ENERGY SECURITY IN AN UNPREDICTABLE WORLD: MAKING THE CASE AGAINST STATE AID LIMITATIONS IN ELECTRICITY GENERATION -- 32 DELIVERING A LOW-CARBON ELECTRICITY SYSTEM IN A LIBERALISED MARKET -- 33 A PROPOSAL FOR REFORMING AN ELECTRICITY MARKET FOR A LOW-CARBON ECONOMY -- 34 THE ROLE OF THE DEMAND SIDE IN ELECTRICITY -- 35 REPLACING FOSSIL FUEL GENERATION WITH RENEWABLE ELECTRICITY: IS MARKET INTEGRATION OR MARKET CIRCUMVENTION THE WAY FORWARD? -- 36 SUSCEPTIBILITY OF ELECTRICITY GENERATION TO CLIMATE VARIABILITY AND CHANGE IN EUROPE: A REVIEW OF LITERATURE -- 37 THE EXTERNAL DIMENSION OF CROSSBORDER ELECTRICITY TRANSMISSION PLANNING IN THE EU -- 38 INTEGRATING VEHICLES AND THE ELECTRICITY GRID TO STORE AND USE RENEWABLE ENERGY -- 39 A STITCH IN TIME: COULD IRELAND'S FORTHCOMING WHITE PAPER BREATHE NEW LIFE INTO ITS BRAVE BUT FALTERING RENEWABLE ELECTRICITY POLICY? -- 40 RECENT DEVELOPMENTS IN THE HUNGARIAN ELECTRICITY REGULATORY FRAMEWORK -- PART 5 NUCLEAR ENERGY -- 41 DELIVERING THE REVIVAL OF NUCLEAR POWER -- 42 ENERGY POLICY: THE ROLE OF NUCLEAR POWER -- 43 FINANCING NEW NUCLEAR POWER STATIONS -- 44 UK NUCLEAR NEW-BUILD PLANS IN THE LIGHT OF INTERNATIONAL EXPERIENCE -- 45 DELIVERING UK NUCLEAR POWER IN THE CONTEXT OF EUROPEAN ENERGY POLICY: THE CHALLENGES AHEAD -- 46 NUCLEAR LIABILITY: CURRENT ISSUES AND WORK IN PROGRESS FOR THE FUTURE -- 47 THE PRESENT STATUS OF NUCLEAR THIRD-PARTY LIABILITY AND NUCLEAR INSURANCE -- 48 SMALL MODULAR REACTORS: THE FUTURE OR THE SWANSONG OF THE NUCLEAR INDUSTRY? -- PART 6 RENEWABLE ENERGY -- 49 COHERENT PROMOTION OF RENEWABLES UNDER A CARBON EMISSIONS CAP -- 50 RENEWABLE ENERGY POLICIES CHANGE CARBON EMISSIONS EVEN UNDER EMISSIONS TRADING -- 51 THE RENEWABLE TRAJECTORY: AVOIDING THE TEMPTATION OF CHEAP OIL -- 52 IMPACT OF RENEWABLE PORTFOLIO STANDARDS ON IN-STATE RENEWABLE DEPLOYMENT IN THE US -- 53 RENEWABLE SUPPORT POLICIES IN EUROPE: EVALUATION OF THE PUSH-PULL FRAMEWORK FOR WIND AND PV IN THE EU -- 54 A VIEW FROM THE GLOBAL WIND INDUSTRY -- 55 THE NEW CONCEPT OF COMPETITIVE BIDDING ON PHOTOVOLTAIC IN THE GERMAN RENEWABLE ENERGY ACT 2014 -- 56 LEGAL CERTAINTY FOR GREEN ENERGY PROJECTS: SURE, BUT AT WHAT PRICE? -- 57 THE FUTURE OF HYDROELECTRIC POWER IN THE UNITED STATES: THINKING SMALL -- 58 HYDROPOWER: FROM PAST TO FUTURE UNCERTAINTIES -- 59 RENEWABLE ENERGY PRODUCTION IN MARINE AREAS AND COASTAL ZONE: THE NORWEGIAN MODEL -- 60 THE GEOPOLITICS OF CLEAN ENERGY: RE-ENGAGING WITH RUSSIA THROUGH RENEWABLE ENERGY COOPERATION -- PART 7 FOSSIL FUELS -- 61 TALKING ABOUT SHALE IN ANY LANGUAGE -- 62 THE SHALE REVOLUTION, FRACKING AND REGULATORY ACTIVITY IN THE US: A POLICY DIVIDED -- 63 FRACTURED SYSTEMS: A MULTIPLE POLICY PROPOSAL FOR PROMOTING SAFE SHALE GAS DELIVERY IN THE UNITED STATES -- 64 PREPARING PENNSYLVANIA FOR A POST-SHALE FUTURE -- 65 THE DECLINE OF COAL AND THE ECONOMIC TOLL ON THE APPALACHIAN REGION -- 66 THE EU NETWORK CODES AND PROSPECTS OF CROSS-BORDER NATURAL GAS PIPELINE PROJECTS -- 67 BUILDING THE ENERGY UNION: THE PROBLEM OF CROSS-BORDER GAS PIPELINE INTERCONNECTIONS IN BALTIC, CENTRAL AND SOUTHEASTERN EUROPE -- 68 EMINENT DOMAIN AUTHORITY FOR UPSTREAM GAS INFRASTRUCTURE: AN ALTERNATIVE APPROACH -- 69 PETROLEUM LICENSING ON THE UKCS FIFTY YEARS ON: PROBLEMS, SOLUTIONS AND MORE PROBLEMS? -- 70 GREENLAND OFFSHORE PETROLEUM REGULATION TOWARDS 'THE BLUE ARCTIC' -- PART 8 ENERGY JUSTICE -- 71 ENERGY JUSTICE: THE YIN AND YANG APPROACH -- 72 SUSTAINABLE DEVELOPMENT AND ENERGY JUSTICE: TWO AGENDAS COMBINED -- 73 ASSESSING THE JUSTICE IMPLICATIONS OF ENERGY INFRASTRUCTURAL DEVELOPMENT IN THE ARCTIC -- PART 9 ENERGY POVERTY AND HEALTH -- 74 ENERGY POVERTY AND AFFORDABLE SUSTAINABLE ENERGY TECHNOLOGIES (ASETS) -- 75 CHALLENGING ENERGY POVERTY POLICIES: INSIGHTS FROM SOUTH-EASTERN EUROPE -- 76 POLICY CHANGES FOR FUTUREPROOFING HOUSING STOCK -- 77 CHALLENGES FOR HEALTH SERVICES IN IDENTIFYING WHICH GROUPS ARE MOST VULNERABLE TO HEALTH IMPACTS OF COLD HOMES -- 78 ENERGY, LIFE, METABOLISM AND THE FOOD CHAIN -- PART 10 ENERGY EFFICIENCY AND DEMAND -- 79 ENERGY EFFICIENCY AND ENERGY DEMAND -- 80 ENERGY DEMAND REDUCTION POLICY -- 81 DEMAND RESPONSE IN WHOLESALE MARKETS -- 82 PERCEIVED EFFECTIVENESS OF DIFFERENT METHODS OF DELIVERING INFORMATION ON ENERGY EFFICIENCY -- 83 DEVELOPING BEHAVIOURAL INTERVENTIONS: THREE LESSONS LEARNED FOR DELIVERING ENERGY POLICY -- 84 POLICY MIXES IN STIMULATING ENERGY TRANSITIONS: THE CASE OF UK ENERGY EFFICIENCY POLICY -- 85 THE JOURNEY OF SMART METERING IN GREAT BRITAIN: A REVISIT -- 86 RETHINKING HOUSEHOLD ENERGY CONSUMPTION STRATEGIES: THE IMPORTANCE OF DEMAND AND EXPECTATIONS -- 87 FINANCIAL INCENTIVES FOR ENERGYEFFICIENT APPLIANCES -- PART 11 ENERGY SECURITY -- 88 ENERGY SECURITY AND ENERGY POLICY INCOHERENCE -- 89 DESIGNING INTERNATIONAL TRADE IN ENERGY GOVERNANCE FOR EU ENERGY SECURITY -- 90 NATO AND EUROPEAN ENERGY SECURITY -- 91 GENEALOGY OF THE CURRENT GAS SECURITY SITUATION IN THE EU-UKRAINE-RUSSIA ENERGY TRIANGLE AND THE ROLE OF INTERNATIONAL LAW -- PART 12 COUNTRY-SPECIFIC AND INTERNATIONAL ENERGY POLICY DELIVERY -- 92 GERMAN ENERGY LAW -- 93 DELIVERING ENERGY LAW AND POLICY IN MALTA -- 94 DELIVERING ENERGY EFFICIENCY POLICIES IN ROMANIA -- 95 ENERGY LAW IN THE CZECH REPUBLIC: 'UNBUNDLING' ČEZ -- 96 DELIVERING ENERGY POLICY REFORM IN UKRAINE: LEGAL ISSUES IN THE LIGHT OF EUROPEAN INTEGRATION -- 97 A SYSTEMIC APPROACH TO RENEWABLE ELECTRICITY TECHNOLOGY DEPLOYMENT: THE 'MISSING LINK' IN OPTIMISING POLICY DELIVERY IN THE UK? -- 98 DELIVERING ENERGY POLICY: IS THERE NEED FOR KEY CHANGES IN THE NEXT UK PARLIAMENTARY PERIOD? -- 99 ENERGY AND THE STATE IN THE MIDDLE EAST -- 100 DELIVERING ENERGY POLICY IN ARGENTINA -- 101 THE ARCTIC: SOURCE OF ENERGY? SOURCE OF CONFLICT? SOURCE OF POLICY INNOVATION -- PART 13 CITIES, COMMUNITY ENERGY AND PUBLIC ENGAGEMENT -- 102 DELIVERING ENERGY (OFTEN) REQUIRES PUBLIC

Context. Realistic synthetic observations of theoretical source models are essential for our understanding of real observational data. In using synthetic data, one can verify the extent to which source parameters can be recovered and evaluate how various data corruption effects can be calibrated. These studies are the most important when proposing observations of new sources, in the characterization of the capabilities of new or upgraded instruments, and when verifying model-based theoretical predictions in a direct comparison with observational data. Aims. We present the SYnthetic Measurement creator for long Baseline Arrays (SYMBA), a novel synthetic data generation pipeline for Very Long Baseline Interferometry (VLBI) observations. SYMBA takes into account several realistic atmospheric, instrumental, and calibration effects. Methods. We used SYMBA to create synthetic observations for the Event Horizon Telescope (EHT), a millimetre VLBI array, which has recently captured the first image of a black hole shadow. After testing SYMBA with simple source and corruption models, we study the importance of including all corruption and calibration effects, compared to the addition of thermal noise only. Using synthetic data based on two example general relativistic magnetohydrodynamics (GRMHD) model images of M 87, we performed case studies to assess the image quality that can be obtained with the current and future EHT array for different weather conditions. Results. Our synthetic observations show that the effects of atmospheric and instrumental corruptions on the measured visibilities are significant. Despite these effects, we demonstrate how the overall structure of our GRMHD source models can be recovered robustly with the EHT2017 array after performing calibration steps, which include fringe fitting, a priori amplitude and network calibration, and self-calibration. With the planned addition of new stations to the EHT array in the coming years, images could be reconstructed with higher angular resolution and dynamic range. In our case study, these improvements allowed for a distinction between a thermal and a non-thermal GRMHD model based on salient features in reconstructed images. © 2020 ESO. ; This work is supported by the ERC Synergy Grant "BlackHoleCam: Imaging the Event Horizon of Black Holes" (Grant 610058). I. Natarajan and R. Deane are grateful for the support from the New Scientific Frontiers with Precision Radio Interferometry Fellowship awarded by the South African Radio Astronomy Observatory (SARAO), which is a facility of the National Research Foundation (NRF), an agency of the Department of Science and Technology (DST) of South Africa. The authors of the present paper further thank the following organizations and programmes: the Academy of Finland (projects 274477, 284495, 312496); the Advanced European Network of E-infrastructures for Astronomy with the SKA (AENEAS) project, supported by the European Commission Framework Programme Horizon 2020 Research and Innovation action under grant agreement 731016; the Alexander von Humboldt Stiftung; the Black Hole Initiative at Harvard University, through a grant (60477) from the John Templeton Foundation; the China Scholarship Council; Comision Nacional de Investigacio Cientifica y Tecnologica (CONICYT, Chile, via PIA ACT172033, Fondecyt 1171506, BASAL AFB-170002, ALMAconicyt 31140007); Consejo Nacional de Ciencia y Tecnologia (CONACYT, Mexico, projects 104497, 275201, 279006, 281692); the Delaney Family via the Delaney Family John A. Wheeler Chair at Perimeter Institute; Direccion General de Asuntos del Personal Academico-Universidad Nacional Autonoma de Mexico (DGAPA-UNAM, project IN112417); the Generalitat Valenciana postdoctoral grant APOSTD/2018/177; the Gordon and Betty Moore Foundation (grants GBMF-3561, GBMF-5278); the Istituto Nazionale di Fisica Nucleare (INFN) sezione di Napoli, iniziative specifiche TEONGRAV; the GenT Program (Generalitat Valenciana) under project CIDEGENT/2018/021; the International Max Planck Research School for Astronomy and Astrophysics at the Universities of Bonn and Cologne; the Jansky Fellowship program of the National Radio Astronomy Observatory (NRAO); the Japanese Government (Monbukagakusho: MEXT) Scholarship; the Japan Society for the Promotion of Science (JSPS) Grant-in-Aid for JSPS Research Fellowship (JP17J08829); the Key Research Program of Frontier Sciences, Chinese Academy of Sciences (CAS, grants QYZDJ-SSW-SLH057, QYZDJ-SSW-SYS008); the Leverhulme Trust Early Career Research Fellowship; the Max-Planck-Gesellschaft (MPG); the Max Planck Partner Group of the MPG and the CAS; the MEXT/JSPS KAKENHI (grants 18KK0090, JP18K13594, JP18K03656, JP18H03721, 18K03709, 18H01245, 25120007); the MIT International Science and Technology Initiatives (MISTI) Funds; the Ministry of Science and Technology (MOST) of Taiwan (105-2112-M-001-025-MY3, 106-2112-M-001-011, 106-2119-M-001027, 107-2119-M-001-017, 107-2119-M-001-020, and 107-2119-M-110-005); the National Aeronautics and Space Administration (NASA, Fermi Guest Investigator grant 80NSSC17K0649); NASA through the NASA Hubble Fellowship grant #HST-HF2-51431.001-A awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc. , for NASA, under contract NAS5-26555; the National Institute of Natural Sciences (NINS) of Japan; the National Key Research and Development Program of China (grant 2016YFA0400704, 2016YFA0400702); the National Science Foundation (NSF, grants AST-0096454, AST-0352953, AST-0521233, AST-0705062, AST-0905844, AST-0922984, AST-1126433, AST-1140030, DGE-1144085, AST-1207704, AST-1207730, AST-1207752, MRI-1228509, OPP-1248097, AST-1310896, AST-1312651, AST-1337663, AST-1440254, AST-1555365, AST-1715061, AST-1615796, AST-1716327, OISE-1743747, AST-1816420); the Natural Science Foundation of China (grants 11573051, 11633006, 11650110427, 10625314, 11721303, 11725312, 11933007); the Natural Sciences and Engineering Research Council of Canada (NSERC, including a Discovery Grant and the NSERC Alexander Graham Bell Canada Graduate Scholarships-Doctoral Program); the National Youth Thousand Talents Program of China; the National Research Foundation of Korea (the Global PhD Fellowship Grant: grants NRF-2015H1A2A1033752, 2015-R1D1A1A01056807, the Korea Research Fellowship Program: NRF-2015H1D3A1066561); the Netherlands Organization for Scientific Research (NWO) VICI award (grant 639.043.513) and Spinoza Prize SPI 78-409; the New Scientific Frontiers with Precision Radio Interferometry Fellowship awarded by the South African Radio Astronomy Observatory (SARAO), which is a facility of the National Research Foundation (NRF), an agency of the Department of Science and Technology (DST) of South Africa; the Onsala Space Observatory (OSO) national infrastructure, for the provisioning of its facilities/observational support (OSO receives funding through the Swedish Research Council under grant 2017-00648) the Perimeter Institute for Theoretical Physics (research at Perimeter Institute is supported by the Government of Canada through the Department of Innovation, Science and Economic Development and by the Province of Ontario through the Ministry of Research, Innovation and Science); the Princeton/Flatiron Postdoctoral Prize Fellowship; the Russian Science Foundation (grant 17-12-01029); the Spanish Ministerio de Economia y Competitividad (grants AYA2015-63939-C21-P, AYA2016-80889-P); the State Agency for Research of the Spanish MCIU through the "Center of Excellence Severo Ochoa" award for the Instituto de Astrofisica de Andalucia (SEV-2017-0709); the Toray Science Foundation; the US Department of Energy (USDOE) through the Los Alamos National Laboratory (operated by Triad National Security, LLC, for the National Nuclear Security Administration of the USDOE (Contract 89233218CNA000001)); the Italian Ministero dell'Istruzione Universita e Ricerca through the grant Progetti Premiali 2012-iALMA (CUP C52I13000140001); the European Union's Horizon 2020 research and innovation programme under grant agreement No 730562 RadioNet; ALMA North America Development Fund; the Academia Sinica; Chandra TM6-17006X. This work used the Extreme Science and Engineering Discovery Environment (XSEDE), supported by NSF grant ACI-1548562, and CyVerse, supported by NSF grants DBI-0735191, DBI-1265383, and DBI1743442. XSEDE Stampede2 resource at TACC was allocated through TGAST170024 and TG-AST080026N. XSEDE JetStream resource at PTI and TACC was allocated through AST170028. The simulations were performed in part on the SuperMUC cluster at the LRZ in Garching, on the LOEWE cluster in CSC in Frankfurt, and on the HazelHen cluster at the HLRS in Stuttgart. This research was enabled in part by support provided by Compute Ontario (http://computeontario.ca), Calcul Quebec (http://www. calculquebec.ca) and Compute Canada (http://www.computecanada.ca).We thank the sta ff at the participating observatories, correlation centers, and institutions for their enthusiastic support. This paper makes use of the following ALMA data: ADS/JAO.ALMA#2017.1.00841.V. ALMA is a partnership of the European Southern Observatory (ESO; Europe, representing its member states), NSF, and National Institutes of Natural Sciences of Japan, together with National Research Council (Canada), Ministry of Science and Technology (MOST; Taiwan), Academia Sinica Institute of Astronomy and Astrophysics (ASIAA; Taiwan), and Korea Astronomy and Space Science Institute (KASI; Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, Associated Universities, Inc. (AUI)/NRAO, and the National Astronomical Observatory of Japan (NAOJ). The NRAO is a facility of the NSF operated under cooperative agreement by AUI. APEX is a collaboration between the Max-Planck-Institut fur Radioastronomie (Germany), ESO, and the Onsala Space Observatory (Sweden). The SMA is a joint project between the SAO and ASIAA and is funded by the Smithsonian Institution and the Academia Sinica. The JCMT is operated by the East Asian Observatory on behalf of the NAOJ, ASIAA, and KASI, as well as the Ministry of Finance of China, Chinese Academy of Sciences, and the National Key R&D Program (No. 2017YFA0402700) of China. Additional funding support for the JCMT is provided by the Science and Technologies Facility Council (UK) and participating universities in the UK and Canada. The LMT is a project operated by the Instituto Nacional de Astrofisica, Optica, y Electronica (Mexico) and the University of Massachusetts at Amherst (USA). The IRAM 30m telescope on Pico Veleta, Spain is operated by IRAM and supported by CNRS (Centre National de la Recherche Scientifique, France), MPG (Max-Planck-Gesellschaft, Germany) and IGN (Instituto Geografico Nacional, Spain). The SMT is operated by the Arizona Radio Observatory, a part of the Steward Observatory of the University of Arizona, with financial support of operations from the State of Arizona and financial support for instrumentation development from the NSF. The SPT is supported by the National Science Foundation through grant PLR-1248097. Partial support is also provided by the NSF Physics Frontier Center grant PHY-1125897 to the Kavli Institute of Cosmological Physics at the University of Chicago, the Kavli Foundation and the Gordon and Betty Moore Foundation grant GBMF 947. The SPT hydrogen maser was provided on loan from the GLT, courtesy of ASIAA. The EHTC has received generous donations of FPGA chips from Xilinx Inc., under the Xilinx University Program. The EHTC has benefited from technology shared under open-source license by the Collaboration for Astronomy Signal Processing and Electronics Research (CASPER). The EHT project is grateful to T4Science and Microsemi for their assistance with Hydrogen Masers. This research has made use of NASA's Astrophysics Data System. We gratefully acknowledge the support provided by the extended staff of the ALMA, both from the inception of the ALMA Phasing Project through the observational campaigns of 2017 and 2018. We would like to thank A. Deller and W. Brisken for EHT-specific support with the use of DiFX. We acknowledge the significance that Maunakea, where the SMA and JCMT EHT stations are located, has for the indigenous Hawaiian people. The software presented in this work makes use of the Numpy (van derWalt et al. 2011), Scipy (Jones et al. 2001), Astropy (Astropy Collaboration 2013, 2018) libraries and the KERN software bundle (Molenaar & Smirnov 2018).

The Event Horizon Telescope Collaboration ; Recent developments in compact object astrophysics, especially the discovery of merging neutron stars by LIGO, the imaging of the black hole in M87 by the Event Horizon Telescope, and high- precision astrometry of the Galactic Center at close to the event horizon scale by the GRAVITY experiment motivate the development of numerical source models that solve the equations of general relativistic magnetohydrodynamics (GRMHD). Here we compare GRMHD solutions for the evolution of a magnetized accretion flow where turbulence is promoted by the magnetorotational instability from a set of nine GRMHD codes: Athena++, BHAC, Cosmos++, ECHO, H-AMR, iharm3D, HARM-Noble, IllinoisGRMHD, and KORAL. Agreement among the codes improves as resolution increases, as measured by a consistently applied, specially developed set of code performance metrics. We conclude that the community of GRMHD codes is mature, capable, and consistent on these test problems. © 2019. The American Astronomical Society. All rights reserved. ; R.N. thanks the National Science Foundation (NSF; grants OISE-1743747, AST-1816420) and acknowledges computational support from the NSF via XSEDE resources (grant TG-AST080026N). L.D.Z. acknowledges support from the PRIN-MIUR project Multi-scale Simulations of High-Energy Astrophysical Plasmas (Prot. 2015L5EE2Y) and from the INFN-TEONGRAV initiative. C.J.W. made use of thComision Nacional de Investigacion Cientifica y Tecnologica (CONICYT, ChileComision Nacional de Investigacion Cientifica y Tecnologica (CONICYT, Chilee Extreme Science and Engineering Discovery Environment (XSEDE) Comet at the San Diego Supercomputer Center through allocation AST170012. The H-AMR high-resolution simulation was made possible by NSF PRAC award Nos. 1615281 and OAC-1811605 at the Blue Waters sustained-petascale computing project and supported in part under grant No. NSF PHY-1125915 (PI A. Tchekhovskoy). K.C. and S.M. are supported by the Netherlands Organization for Scientific Research (NWO) VICI grant (No. 639.043.513); M.L. is supported by the NWO Spinoza Prize (PI M.B.M. van der Klis). The HARM-Noble simulations were made possible by NSF PRAC award No. NSF OAC-1515969, OAC-1811228 at the Blue Waters sustained-petascale computing project, and supported in part under grant No. NSF PHY-1125915. The BHAC CKS-GRMHD simulations were performed on the Dutch National Supercomputing cluster Cartesius and are funded by the NWO computing grant 16431. S.C.N. was supported by an appointment to the NASA Postdoctoral Program at the Goddard Space Flight Center administered by USRA through a contract with NASA. Y.M., H.O., O.P., and L.R. acknowledge support from the ERC synergy grant >BlackHoleCam: Imaging the Event Horizon of Black Holes> (grant No. 610058). M.B. acknowledges support from the European Research Council (grant No. 715368-MagBURST) and from the Gauss Centre for Supercomputing e.V. (www.Gauss-centre.eu) for funding this project by providing computing time on the GCS Supercomputer SuperMUC at Leibniz Supercomputing Centre (www.lrz.de).P.C.F.was supported by NSF grant AST-1616185 and used resources from the Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by NSF grant No. ACI-1548562. Work by P.A. was performed in part under the auspices of the US Department of Energy by Lawrence Livermore National Laboratory under contract DE-AC52-07NA27344. The authors of the present paper further thank the following organizations and programs: the Academy of Finland (projects 274477, 284495, 312496); the Advanced European Network of E-infrastructures for Astronomy with the SKA (AENEAS) project, supported by the European Commission Framework Programme Horizon 2020 Research and Innovation action under grant agreement 731016; the Alexander von Humboldt Stiftung; the Black Hole Initiative at Harvard University, through a grant (60477) from the John Templeton Foundation; the China Scholarship Council; Comision Nacional de Investigacion Cientifica y Tecnologica (CONICYT, Chile, via PIA ACT172033, Fondecyt 1171506, BASAL AFB-170002, ALMA-conicyt 31140007); Consejo Nacional de Ciencia y Tecnologia (CONACYT, Mexico, projects 104497, 275201, 279006, 281692); the Delaney Family via the Delaney Family John A. Wheeler Chair at Perimeter Institute; Direccion General de Asuntos del Personal Academico-Universidad Nacional Autonoma de Mexico (DGAPA-UNAM, project IN112417); the European Research Council Synergy Grant >BlackHoleCam: Imaging the Event Horizon of Black Holes> (grant 610058); the Generalitat Valenciana postdoctoral grant APOSTD/2018/177; the Gordon and Betty Moore Foundation (grants GBMF-3561, GBMF-5278); the Istituto Nazionale di Fisica Nucleare (INFN) sezione di Napoli, iniziative specifiche TEONGRAV; the International Max Planck Research School for Astronomy and Astrophysics at the Universities of Bonn and Cologne; the Jansky Fellowship program of the National Radio Astronomy Observatory (NRAO); the Japanese Government (Monbukagakusho: MEXT) Scholarship; the Japan Society for the Promotion of Science (JSPS) Grant-in-Aid for JSPS Research Fellowship (JP17J08829); the Key Research Program of Frontier Sciences, Chinese Academy of Sciences (CAS, grants QYZDJ-SSW-SLH057, QYZDJ-SSW-SYS008); the Leverhulme Trust Early Career Research Fellowship; the Max-Planck-Gesellschaft (MPG); the Max Planck Partner Group of the MPG and the CAS; the MEXT/JSPS KAKENHI (grants 18KK0090, JP18K13594, JP18K03656, JP18H03721, 18K03709, 18H01245, 25120007); the MIT International Science and Technology Initiatives (MISTI) Funds; the Ministry of Science and Technology (MOST) of Taiwan (105-2112-M-001-025-MY3, 106-2112-M-001-011, 106-2119-M-001-027, 107-2119-M-001-017, 107-2119-M-001-020, and 107-2119-M-110-005); the National Aeronautics and Space Administration (NASA, Fermi Guest Investigator grant 80NSSC17K0649); the National Institute of Natural Sciences (NINS) of Japan; the National Key Research and Development Program of China (grant 2016YFA0400704, 2016YFA0400702); the National Science Foundation (NSF, grants AST-0096454, AST-0352953, AST-0521233, AST-0705062, AST-0905844, AST-0922984, AST-1126433, AST-1140030, DGE-1144085, AST-1207704, AST-1207730, AST-1207752, MRI-1228509, OPP-1248097, AST-1310896, AST-1312651, AST-1337663, AST-1440254, AST-1555365, AST-1715061, AST-1615796, AST-1716327, OISE-1743747, AST-1816420); the Natural Science Foundation of China (grants 11573051, 11633006, 11650110427, 10625314, 11721303, 11725312); the Natural Sciences and Engineering Research Council of Canada (NSERC, including a Discovery Grant and the NSERC Alexander Graham Bell Canada Graduate Scholarships Doctoral Program); the National Youth Thousand Talents Program of China; the National Research Foundation of Korea (the Global PhD Fellowship Grant: grants NRF-2015H1A2A1033752, 2015-R1D1A1A01056807, the Korea Research Fellowship Program: NRF-2015H1D3A1066561); the Netherlands Organization for Scientific Research (NWO) VICI award (grant 639.043. 513) and Spinoza Prize SPI 78-409; the New Scientific Frontiers with Precision Radio Interferometry Fellowship awarded by the South African Radio Astronomy Observatory (SARAO), which is a facility of the National Research Foundation (NRF), an agency of the Department of Science and Technology (DST) of South Africa; the Onsala Space Observatory (OSO) national infrastructure, for the provisioning of its facilities/observational support (OSO receives funding through the Swedish Research Council under grant 2017-00648); the Perimeter Institute for Theoretical Physics (research at Perimeter Institute is supported by the Government of Canada through the Department of Innovation, Science and Economic Development, and by the Province of Ontario through the Ministry of Research, Innovation and Science); the Russian Science Foundation (grant 17-12-01029); the Spanish Ministerio de Economia y Competitividad (grants AYA2015-63939-C2-1-P, AYA2016-80889-P); the State Agency for Research of the Spanish MCIU through the >Center of Excellence Severo Ochoa> award for the Instituto de Astrofisica de Andalucia (SEV-2017-0709); the Toray Science Foundation; the US Department of Energy (USDOE) through the Los Alamos National Laboratory (operated by Triad National Security, LLC, for the National Nuclear Security Administration of the USDOE (Contract 89233218CNA000001)); the Italian Ministero dell'Istruzione Universita e Ricerca through the grant Progetti Premiali 2012-iALMA (CUP C52I13000140001); the European Union's Horizon 2020 research and innovation programme under grant agreement No. 730562 RadioNet; ALMA North America Development Fund; the Academia Sinica; and Chandra TM6-17006X. This work used the Extreme Science and Engineering Discovery Environment (XSEDE), supported by NSF grant ACI-1548562, and CyVerse, supported by NSF grants DBI-0735191, DBI-1265383, and DBI-1743442. XSEDE Stampede2 resource at TACC was allocated through TG-AST170024 and TG-AST080026N. XSEDE JetStream resource at PTI and TACC was allocated through AST170028. The simulations were performed in part on the SuperMUC cluster at the LRZ in Garching, on the LOEWE cluster in CSC in Frankfurt, and on the HazelHen cluster at the HLRS in Stuttgart. This research was enabled in part by support provided by Compute Ontario (http://computeontario.ca), Calcul Quebec (http://www.calculquebec.ca), and Compute Canada (http://www.computecanada.ca).