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Showing papers by "Colorado State University published in 2017"


Journal ArticleDOI
B. P. Abbott1, Richard J. Abbott1, T. D. Abbott2, Fausto Acernese3  +1131 moreInstitutions (123)
TL;DR: The association of GRB 170817A, detected by Fermi-GBM 1.7 s after the coalescence, corroborates the hypothesis of a neutron star merger and provides the first direct evidence of a link between these mergers and short γ-ray bursts.
Abstract: On August 17, 2017 at 12∶41:04 UTC the Advanced LIGO and Advanced Virgo gravitational-wave detectors made their first observation of a binary neutron star inspiral. The signal, GW170817, was detected with a combined signal-to-noise ratio of 32.4 and a false-alarm-rate estimate of less than one per 8.0×10^{4} years. We infer the component masses of the binary to be between 0.86 and 2.26 M_{⊙}, in agreement with masses of known neutron stars. Restricting the component spins to the range inferred in binary neutron stars, we find the component masses to be in the range 1.17-1.60 M_{⊙}, with the total mass of the system 2.74_{-0.01}^{+0.04}M_{⊙}. The source was localized within a sky region of 28 deg^{2} (90% probability) and had a luminosity distance of 40_{-14}^{+8} Mpc, the closest and most precisely localized gravitational-wave signal yet. The association with the γ-ray burst GRB 170817A, detected by Fermi-GBM 1.7 s after the coalescence, corroborates the hypothesis of a neutron star merger and provides the first direct evidence of a link between these mergers and short γ-ray bursts. Subsequent identification of transient counterparts across the electromagnetic spectrum in the same location further supports the interpretation of this event as a neutron star merger. This unprecedented joint gravitational and electromagnetic observation provides insight into astrophysics, dense matter, gravitation, and cosmology.

7,327 citations


Journal ArticleDOI
B. P. Abbott1, Richard J. Abbott1, T. D. Abbott2, Fausto Acernese3  +1195 moreInstitutions (139)
TL;DR: In this paper, the authors used the observed time delay of $(+1.74\pm 0.05)\,{\rm{s}}$ between GRB 170817A and GW170817 to constrain the difference between the speed of gravity and speed of light to be between $-3
Abstract: On 2017 August 17, the gravitational-wave event GW170817 was observed by the Advanced LIGO and Virgo detectors, and the gamma-ray burst (GRB) GRB 170817A was observed independently by the Fermi Gamma-ray Burst Monitor, and the Anti-Coincidence Shield for the Spectrometer for the International Gamma-Ray Astrophysics Laboratory. The probability of the near-simultaneous temporal and spatial observation of GRB 170817A and GW170817 occurring by chance is $5.0\times {10}^{-8}$. We therefore confirm binary neutron star mergers as a progenitor of short GRBs. The association of GW170817 and GRB 170817A provides new insight into fundamental physics and the origin of short GRBs. We use the observed time delay of $(+1.74\pm 0.05)\,{\rm{s}}$ between GRB 170817A and GW170817 to: (i) constrain the difference between the speed of gravity and the speed of light to be between $-3\times {10}^{-15}$ and $+7\times {10}^{-16}$ times the speed of light, (ii) place new bounds on the violation of Lorentz invariance, (iii) present a new test of the equivalence principle by constraining the Shapiro delay between gravitational and electromagnetic radiation. We also use the time delay to constrain the size and bulk Lorentz factor of the region emitting the gamma-rays. GRB 170817A is the closest short GRB with a known distance, but is between 2 and 6 orders of magnitude less energetic than other bursts with measured redshift. A new generation of gamma-ray detectors, and subthreshold searches in existing detectors, will be essential to detect similar short bursts at greater distances. Finally, we predict a joint detection rate for the Fermi Gamma-ray Burst Monitor and the Advanced LIGO and Virgo detectors of 0.1–1.4 per year during the 2018–2019 observing run and 0.3–1.7 per year at design sensitivity.

2,633 citations


Journal ArticleDOI
B. P. Abbott1, Richard J. Abbott1, T. D. Abbott2, Fausto Acernese3  +1113 moreInstitutions (117)
TL;DR: For the first time, the nature of gravitational-wave polarizations from the antenna response of the LIGO-Virgo network is tested, thus enabling a new class of phenomenological tests of gravity.
Abstract: On August 14, 2017 at 10∶30:43 UTC, the Advanced Virgo detector and the two Advanced LIGO detectors coherently observed a transient gravitational-wave signal produced by the coalescence of two stellar mass black holes, with a false-alarm rate of ≲1 in 27 000 years. The signal was observed with a three-detector network matched-filter signal-to-noise ratio of 18. The inferred masses of the initial black holes are 30.5-3.0+5.7M⊙ and 25.3-4.2+2.8M⊙ (at the 90% credible level). The luminosity distance of the source is 540-210+130 Mpc, corresponding to a redshift of z=0.11-0.04+0.03. A network of three detectors improves the sky localization of the source, reducing the area of the 90% credible region from 1160 deg2 using only the two LIGO detectors to 60 deg2 using all three detectors. For the first time, we can test the nature of gravitational-wave polarizations from the antenna response of the LIGO-Virgo network, thus enabling a new class of phenomenological tests of gravity.

1,979 citations


Journal ArticleDOI
TL;DR: It is shown that NCS can provide over one-third of the cost-effective climate mitigation needed between now and 2030 to stabilize warming to below 2 °C.
Abstract: Better stewardship of land is needed to achieve the Paris Climate Agreement goal of holding warming to below 2 °C; however, confusion persists about the specific set of land stewardship options available and their mitigation potential. To address this, we identify and quantify "natural climate solutions" (NCS): 20 conservation, restoration, and improved land management actions that increase carbon storage and/or avoid greenhouse gas emissions across global forests, wetlands, grasslands, and agricultural lands. We find that the maximum potential of NCS-when constrained by food security, fiber security, and biodiversity conservation-is 23.8 petagrams of CO2 equivalent (PgCO2e) y-1 (95% CI 20.3-37.4). This is ≥30% higher than prior estimates, which did not include the full range of options and safeguards considered here. About half of this maximum (11.3 PgCO2e y-1) represents cost-effective climate mitigation, assuming the social cost of CO2 pollution is ≥100 USD MgCO2e-1 by 2030. Natural climate solutions can provide 37% of cost-effective CO2 mitigation needed through 2030 for a >66% chance of holding warming to below 2 °C. One-third of this cost-effective NCS mitigation can be delivered at or below 10 USD MgCO2-1 Most NCS actions-if effectively implemented-also offer water filtration, flood buffering, soil health, biodiversity habitat, and enhanced climate resilience. Work remains to better constrain uncertainty of NCS mitigation estimates. Nevertheless, existing knowledge reported here provides a robust basis for immediate global action to improve ecosystem stewardship as a major solution to climate change.

1,508 citations


Journal ArticleDOI
B. P. Abbott1, Richard J. Abbott1, T. D. Abbott2, Fausto Acernese3  +1151 moreInstitutions (125)
TL;DR: In this article, a GW signal from the merger of two stellar-mass black holes was observed by the two Advanced Laser Interferometer Gravitational-Wave Observatory detectors with a network signal-to-noise ratio of 13.5%.
Abstract: On 2017 June 8 at 02:01:16.49 UTC, a gravitational-wave (GW) signal from the merger of two stellar-mass black holes was observed by the two Advanced Laser Interferometer Gravitational-Wave Observatory detectors with a network signal-to-noise ratio of 13. This system is the lightest black hole binary so far observed, with component masses of ${12}_{-2}^{+7}\,{M}_{\odot }$ and ${7}_{-2}^{+2}\,{M}_{\odot }$ (90% credible intervals). These lie in the range of measured black hole masses in low-mass X-ray binaries, thus allowing us to compare black holes detected through GWs with electromagnetic observations. The source's luminosity distance is ${340}_{-140}^{+140}\,\mathrm{Mpc}$, corresponding to redshift ${0.07}_{-0.03}^{+0.03}$. We verify that the signal waveform is consistent with the predictions of general relativity.

1,268 citations


Journal ArticleDOI
15 Apr 2017-Geoderma
TL;DR: In this paper, the authors surveyed the soil organic carbon (SOC) stock estimates and sequestration potentials from 20 regions in the world (New Zealand, Chile, South Africa, Australia, Tanzania, Indonesia, Kenya, Nigeria, India, China Taiwan, South Korea, China Mainland, United States of America, France, Canada, Belgium, England & Wales, Ireland, Scotland, and Russia).

1,171 citations



Journal ArticleDOI
TL;DR: It is shown that, across multiple tree species, loss of xylem conductivity above 60% is associated with mortality, while carbon starvation is not universal, indicating that evidence supporting carbon starvation was not universal.
Abstract: Widespread tree mortality associated with drought has been observed on all forested continents and global change is expected to exacerbate vegetation vulnerability. Forest mortality has implications for future biosphere-atmosphere interactions of carbon, water and energy balance, and is poorly represented in dynamic vegetation models. Reducing uncertainty requires improved mortality projections founded on robust physiological processes. However, the proposed mechanisms of drought-induced mortality, including hydraulic failure and carbon starvation, are unresolved. A growing number of empirical studies have investigated these mechanisms, but data have not been consistently analysed across species and biomes using a standardized physiological framework. Here, we show that xylem hydraulic failure was ubiquitous across multiple tree taxa at drought-induced mortality. All species assessed had 60% or higher loss of xylem hydraulic conductivity, consistent with proposed theoretical and modelled survival thresholds. We found diverse responses in non-structural carbohydrate reserves at mortality, indicating that evidence supporting carbon starvation was not universal. Reduced non-structural carbohydrates were more common for gymnosperms than angiosperms, associated with xylem hydraulic vulnerability, and may have a role in reducing hydraulic function. Our finding that hydraulic failure at drought-induced mortality was persistent across species indicates that substantial improvement in vegetation modelling can be achieved using thresholds in hydraulic function.

651 citations


Proceedings Article
13 Nov 2017
TL;DR: This work considers the prediction of interfaces between proteins, a challenging problem with important applications in drug discovery and design, and examines the performance of existing and newly proposed spatial graph convolution operators for this task.
Abstract: We consider the prediction of interfaces between proteins, a challenging problem with important applications in drug discovery and design, and examine the performance of existing and newly proposed spatial graph convolution operators for this task. By performing convolution over a local neighborhood of a node of interest, we are able to stack multiple layers of convolution and learn effective latent representations that integrate information across the graph that represent the three dimensional structure of a protein of interest. An architecture that combines the learned features across pairs of proteins is then used to classify pairs of amino acid residues as part of an interface or not. In our experiments, several graph convolution operators yielded accuracy that is better than the state-of-the-art SVM method in this task.

608 citations


Journal ArticleDOI
TL;DR: This work states that agriculture in 2050: Recalibrating Targets for Sustainable Intensification should be considered as a priority for policy-makers as well as the private sector.
Abstract: http://bioscience.oxfordjournals.org XXXX XXXX / Vol. XX No. X BioScience 1 BioScience XX: 1–6. © The Author(s) 2017. Published by Oxford University Press on behalf of the American Institute of Biological Sciences. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com. doi:10.1093/biosci/bix010 Advance Access publication XXXX XX, XXXX Agriculture in 2050: Recalibrating Targets for Sustainable Intensification

577 citations


Journal ArticleDOI
TL;DR: In this paper, the authors identify priorities for research in this area: (1) develop model host-microbiome systems for crop plants and non-crop plants with associated microbial culture collections and reference genomes, (2) define core microbiomes and metagenomes in these model systems, (3) elucidate the rules of synthetic, functionally programmable microbiome assembly, and (4) determine functional mechanisms of plant microbiome interactions.
Abstract: Feeding a growing world population amidst climate change requires optimizing the reliability, resource use, and environmental impacts of food production. One way to assist in achieving these goals is to integrate beneficial plant microbiomes-i.e., those enhancing plant growth, nutrient use efficiency, abiotic stress tolerance, and disease resistance-into agricultural production. This integration will require a large-scale effort among academic researchers, industry researchers, and farmers to understand and manage plant-microbiome interactions in the context of modern agricultural systems. Here, we identify priorities for research in this area: (1) develop model host-microbiome systems for crop plants and non-crop plants with associated microbial culture collections and reference genomes, (2) define core microbiomes and metagenomes in these model systems, (3) elucidate the rules of synthetic, functionally programmable microbiome assembly, (4) determine functional mechanisms of plant-microbiome interactions, and (5) characterize and refine plant genotype-by-environment-by-microbiome-by-management interactions. Meeting these goals should accelerate our ability to design and implement effective agricultural microbiome manipulations and management strategies, which, in turn, will pay dividends for both the consumers and producers of the world food supply.

Journal ArticleDOI
TL;DR: The GPM mission collects essential rain and snow data for scientific studies and societal benefit and aims to provide real-time information about rainfall and snowfall to improve understanding of climate change.
Abstract: The GPM mission collects essential rain and snow data for scientific studies and societal benefit.

Journal ArticleDOI
Nuno R. Faria1, Joshua Quick2, Ingra Morales Claro3, Julien Thézé1, J G de Jesus4, Marta Giovanetti4, Moritz U. G. Kraemer1, Sarah C. Hill1, Allison Black5, Allison Black6, A. C. da Costa3, L. C Franco7, Sandro Patroca da Silva7, C-H Wu1, Jayna Raghwani1, Simon Cauchemez8, L. du Plessis1, M. P Verotti, W. K. de Oliveira4, Eduardo Hage Carmo, Giovanini E. Coelho, A. C. F. S Santelli4, L. C Vinhal, Cláudio Maierovitch Pessanha Henriques, Jared T. Simpson9, Matthew Loose10, Kristian G. Andersen11, Nathan D. Grubaugh11, Sneha Somasekar12, Charles Y. Chiu12, José Esteban Muñoz-Medina13, César González-Bonilla13, Carlos F. Arias14, Lia Laura Lewis-Ximenez4, Sally A. Baylis15, Alexandre Otavio Chieppe, Shirlei Ferreira Aguiar, Carlos Fernandes, Poliana da Silva Lemos7, B. L. S Nascimento7, Hamilton Antônio de Oliveira Monteiro7, Isadora Cristina de Siqueira4, M. G. de Queiroz, T. R. de Souza, João Felipe Bezerra, M. R Lemos, Gavin Pereira, D Loudal, L. C Moura, Rafael Dhalia4, Rafael F. O. França4, T Magalhães16, T Magalhães4, T Magalhães17, Ernesto T. A. Marques4, Thomas Jaenisch18, Gabriel Luz Wallau4, M. C. de Lima, Vitor H. Nascimento, E. M. de Cerqueira, M. M. de Lima19, D. L Mascarenhas, J. P Moura Neto20, Anna S. Levin3, Tania Regina Tozetto-Mendoza3, Silvia Nunes Szente Fonseca, Maria Cassia Mendes-Correa3, Flavio Augusto de Pádua Milagres21, Aluísio Augusto Cotrim Segurado3, Edward C. Holmes22, Andrew Rambaut23, Andrew Rambaut24, Trevor Bedford6, Márcio Roberto Teixeira Nunes25, Márcio Roberto Teixeira Nunes7, Ester Cerdeira Sabino3, Luiz Carlos Junior Alcantara4, Nicholas J. Loman2, Oliver G. Pybus1 
15 Jun 2017-Nature
TL;DR: The origin and epidemic history of ZIKV in Brazil and the Americas remain poorly understood, despite the value of this information for interpreting observed trends in reported microcephaly and other birth defects as mentioned in this paper.
Abstract: Transmission of Zika virus (ZIKV) in the Americas was first confirmed in May 2015 in northeast Brazil. Brazil has had the highest number of reported ZIKV cases worldwide (more than 200,000 by 24 December 2016) and the most cases associated with microcephaly and other birth defects (2,366 confirmed by 31 December 2016). Since the initial detection of ZIKV in Brazil, more than 45 countries in the Americas have reported local ZIKV transmission, with 24 of these reporting severe ZIKV-associated disease. However, the origin and epidemic history of ZIKV in Brazil and the Americas remain poorly understood, despite the value of this information for interpreting observed trends in reported microcephaly. Here we address this issue by generating 54 complete or partial ZIKV genomes, mostly from Brazil, and reporting data generated by a mobile genomics laboratory that travelled across northeast Brazil in 2016. One sequence represents the earliest confirmed ZIKV infection in Brazil. Analyses of viral genomes with ecological and epidemiological data yield an estimate that ZIKV was present in northeast Brazil by February 2014 and is likely to have disseminated from there, nationally and internationally, before the first detection of ZIKV in the Americas. Estimated dates for the international spread of ZIKV from Brazil indicate the duration of pre-detection cryptic transmission in recipient regions. The role of northeast Brazil in the establishment of ZIKV in the Americas is further supported by geographic analysis of ZIKV transmission potential and by estimates of the basic reproduction number of the virus.

Journal ArticleDOI
TL;DR: In this paper, a review summarizes some of the important developments during the past decade in understanding secondary organic aerosol (SOA) formation, including formation of extremely low volatility organics in the gas phase, acid-catalyzed multiphase chemistry of isoprene epoxydiols, particle-phase oligomerization, and physical properties such as volatility and viscosity.
Abstract: Anthropogenic emissions and land use changes have modified atmospheric aerosol concentrations and size distributions over time. Understanding preindustrial conditions and changes in organic aerosol due to anthropogenic activities is important because these features (1) influence estimates of aerosol radiative forcing and (2) can confound estimates of the historical response of climate to increases in greenhouse gases. Secondary organic aerosol (SOA), formed in the atmosphere by oxidation of organic gases, represents a major fraction of global submicron-sized atmospheric organic aerosol. Over the past decade, significant advances in understanding SOA properties and formation mechanisms have occurred through measurements, yet current climate models typically do not comprehensively include all important processes. This review summarizes some of the important developments during the past decade in understanding SOA formation. We highlight the importance of some processes that influence the growth of SOA particles to sizes relevant for clouds and radiative forcing, including formation of extremely low volatility organics in the gas phase, acid-catalyzed multiphase chemistry of isoprene epoxydiols, particle-phase oligomerization, and physical properties such as volatility and viscosity. Several SOA processes highlighted in this review are complex and interdependent and have nonlinear effects on the properties, formation, and evolution of SOA. Current global models neglect this complexity and nonlinearity and thus are less likely to accurately predict the climate forcing of SOA and project future climate sensitivity to greenhouse gases. Efforts are also needed to rank the most influential processes and nonlinear process-related interactions, so that these processes can be accurately represented in atmospheric chemistry-climate models.

Journal ArticleDOI
TL;DR: In this article, the authors used the Essential Biodiversity Variable framework to describe the range of biodiversity data needed to track progress towards global biodiversity targets, and assessed strengths and gaps in geographical and taxonomic coverage.

Journal ArticleDOI
TL;DR: In this paper, a critical review article captures some selected highlights of the emerging area of recyclable "green polymers" by focusing on the major progress made and the technical and environmental benefits obtained in the development of repurposing and depolymerization processes for chemical recycling of polymers at the end of their useful life.


Journal ArticleDOI
TL;DR: This work focuses on three-Dimensional Electrochemical Detection, which automates the very labor-intensive and therefore time-heavy and expensive process of characterize and characterize the electrochemical activity of the response of the immune system.
Abstract: Applications Yuanyuan Yang,† Eka Noviana,† Michael P. Nguyen,† Brian J. Geiss,‡ David S. Dandy, and Charles S. Henry*,†,§ †Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States ‡Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado 80523, United States Department of Chemical and Biological Engineering, Colorado State University, Fort Collins, Colorado 80523, United States ■ CONTENTS Fabrication 71 Hydrophobic/Solvent Barrier 72 Deposition 73 Flow and Injection Control 74 Three-Dimensional Devices 75 Incorporating Nonsensing Electrodes 75 Colorimetric Detection 75 Detectors and Readout 75 Reflectance-Based Measurement 75 Transmittance-Based Measurement 77 Instrument-Free Measurement 77 Biomedical Applications 77 Enzymatic Methods 77 Immunoassays 78 Other 79 Environmental Applications 79 Other Applications 80 Electrochemical Detection 80 Electrodes 80 Carbon Electrodes 81 Metallic Electrodes 81 Biological Applications 82 Glucose Sensors 82 Immunosensors 84 Other Examples 84 Environmental Applications 84 Other Technologies 85 Chemiluminescence and Electrochemiluminescence 85 Fluorescence 85 Surface-Enhanced Raman Spectroscopy 85 Separation 86 Preconcentration 86 Conclusions and Future Directions 87 Author Information 87 Corresponding Author 87 ORCID 87 Notes 87 Biographies 87 Acknowledgments 88 References 88

Journal ArticleDOI
31 Aug 2017-Stress
TL;DR: The HPA and HPG axes are discussed and how gonadal steroids interact with the HPA axis to regulate the stress circuitry during all stages in life is reviewed.
Abstract: Gonadal hormones play a key role in the establishment, activation, and regulation of the hypothalamic-pituitary-adrenal (HPA) axis. By influencing the response and sensitivity to releasing factors, neurotransmitters, and hormones, gonadal steroids help orchestrate the gain of the HPA axis to fine-tune the levels of stress hormones in the general circulation. From early life to adulthood, gonadal steroids can differentially affect the HPA axis, resulting in sex differences in the responsivity of this axis. The HPA axis influences many physiological functions making an organism's response to changes in the environment appropriate for its reproductive status. Although the acute HPA response to stressors is a beneficial response, constant activation of this circuitry by chronic or traumatic stressful episodes may lead to a dysregulation of the HPA axis and cause pathology. Compared to males, female mice and rats show a more robust HPA axis response, as a result of circulating estradiol levels which elevate stress hormone levels during non-threatening situations, and during and after stressors. Fluctuating levels of gonadal steroids in females across the estrous cycle are a major factor contributing to sex differences in the robustness of HPA activity in females compared to males. Moreover, gonadal steroids may also contribute to epigenetic and organizational influences on the HPA axis even before puberty. Correspondingly, crosstalk between the hypothalamic-pituitary-gonadal (HPG) and HPA axes could lead to abnormalities of stress responses. In humans, a dysregulated stress response is one of the most common symptoms seen across many neuropsychiatric disorders, and as a result, such interactions may exacerbate peripheral pathologies. In this review, we discuss the HPA and HPG axes and review how gonadal steroids interact with the HPA axis to regulate the stress circuitry during all stages in life.

Journal ArticleDOI
TL;DR: A new synthesis that has integrated data from hundreds of studies to document soil carbon responses to changes in management confirms that improving grassland management practices and conversion from cropland to grassland improve soil carbon stocks.
Abstract: Grassland ecosystems cover a large portion of Earths’ surface and contain substantial amounts of soil organic carbon. Previous work has established that these soil carbon stocks are sensitive to management and land use changes: grazing, species composition, and mineral nutrient availability can lead to losses or gains of soil carbon. Because of the large annual carbon fluxes into and out of grassland systems, there has been growing interest in how changes in management might shift the net balance of these flows, stemming losses from degrading grasslands or managing systems to increase soil carbon stocks (i.e., carbon sequestration). A synthesis published in 2001 assembled data from hundreds of studies to document soil carbon responses to changes in management. Here we present a new synthesis that has integrated data from the hundreds of studies published after our previous work. These new data largely confirm our earlier conclusions: improved grazing management, fertilization, sowing legumes and improved grass species, irrigation, and conversion from cultivation all tend to lead to increased soil C, at rates ranging from 0.105 to more than 1 Mg C·ha−1·yr−1. The new data include assessment of three new management practices: fire, silvopastoralism, and reclamation, although these studies are limited in number. The main area in which the new data are contrary to our previous synthesis is in conversion from native vegetation to grassland, where we find that across the studies the average rate of soil carbon stock change is low and not significant. The data in this synthesis confirm that improving grassland management practices and conversion from cropland to grassland improve soil carbon stocks.

Journal ArticleDOI
TL;DR: This article examined three research questions (RQ): (1) To what extent do inconsistencies exist in data (e.g., responses of −2 −2 2 2 2)? (2) Does the number of scale items influence the amount of inconsistency? (3) Does Cronbach's alpha mask inconsistencies?
Abstract: Cronbach's alpha estimates the internal consistency of responses in multi-item bipolar scales. This article examined three research questions (RQ): (1) To what extent do inconsistencies exist in data (e.g., responses of −2 −2 2 2)? (2) Does the number of scale items influence the amount of inconsistency? (3) Does Cronbach's alpha mask inconsistencies? Data were obtained from 29 research projects (n = 10,616). Each survey had place attachment questions comprising two concepts: place identity and place dependence. Respondents were classified as consistent or inconsistent based on their responses to the place attachment questions. Results demonstrated that: (a) inconsistent response patterns existed in the data (RQ1), (b) number of scale items influenced amount of inconsistency (RQ2), and (c) alpha masked these inconsistencies (RQ3). Discussion focused on implications of these findings.

Journal ArticleDOI
A. Aab1, P. Abreu2, Marco Aglietta3, I. Al Samarai4  +415 moreInstitutions (65)
22 Sep 2017-Science
TL;DR: The Pierre Auger Collaboration reports the observation of thousands of cosmic rays with ultrahigh energies of several exa–electron volts, arriving in a slightly dipolar distribution, showing that they originate outside the Milky Way Galaxy.
Abstract: Cosmic rays are atomic nuclei arriving from outer space that reach the highest energies observed in nature Clues to their origin come from studying the distribution of their arrival directions Using 3 × 10 4 cosmic rays with energies above 8 × 10 18 electron volts, recorded with the Pierre Auger Observatory from a total exposure of 76,800 km 2 sr year, we determined the existence of anisotropy in arrival directions The anisotropy, detected at more than a 52σ level of significance, can be described by a dipole with an amplitude of 65 − 09 + 13 percent toward right ascension α d = 100 ± 10 degrees and declination δ d = − 24 − 13 + 12 degrees That direction indicates an extragalactic origin for these ultrahigh-energy particles

Journal ArticleDOI
TL;DR: In this article, a conceptual framework grounded in gossip theory is used to link customer vulnerability to negative performance effects and show that transparency and control in firms' data management practices can suppress the negative effects of customer data vulnerability.
Abstract: Although marketers increasingly rely on customer data, firms have little insight into the ramifications of such data use and do not know how to prevent negative effects. Data management efforts may heighten customers’ vulnerability worries or create real vulnerability. Using a conceptual framework grounded in gossip theory, the authors link customer vulnerability to negative performance effects. Three studies show that transparency and control in firms’ data management practices can suppress the negative effects of customer data vulnerability. Experimental manipulations reveal that mere access to personal data inflates feelings of violation and reduces trust. An event study of data security breaches affecting 414 public companies also confirms negative effects, as well as spillover vulnerabilities from rival firms’ breaches, on firm performance. Severity of the breach hurts the focal firm but helps the rival firm, which provides some insight into mixed findings in prior research. Finally, a field ...

Journal ArticleDOI
TL;DR: In this paper, the authors examine theoretical perspectives and empirical findings about data and information privacy grouped according to privacy's role in society, the psychology of privacy, and the economics of privacy.
Abstract: This paper captures the current state of privacy scholarship in marketing and related disciplines. We examine theoretical perspectives and empirical findings about data and information privacy grouped according to privacy’s role in society, the psychology of privacy, and the economics of privacy. Although a coherent subset of research themes provide deep understanding, theoretical and empirical findings show this narrow focus also has constrained our view of privacy to consumer, organizational, ethical, or legal silos. In response, we take a necessary step toward expanding the privacy domain across these borders, emphasizing the compelling synergies that span multiple interests. We conclude by highlighting future research themes that embody a multidimensional approach, which blends the many interconnected concerns that feature in contemporary privacy questions in marketing. Since internal and external stakeholders are affected in multiple and potentially unforeseen ways by data privacy issues, additional work in this space remains critical and needed.

Journal ArticleDOI
TL;DR: In this paper, the authors discuss the range of approaches to the flipped classroom and focus on activities frequently used in these settings and argue that the value of these activities reflects the particular cognitive processes engaged by the activity regardless of whether the setting is the traditional (lecture-based) classroom or flipped classroom.
Abstract: Flipped classrooms refer to the practice of assigning lectures outside of class and devoting class time to a variety of learning activities. In this review, we discuss the range of approaches to the flipped classroom and focus on activities frequently used in these settings. Amongst these, we examine both out-of-class activities (e.g., video lectures) and in-class activities (e.g., quizzes, student discussions). We argue that the value of these activities reflects the particular cognitive processes engaged by the activity regardless of whether the setting is the traditional (lecture-based) classroom or the flipped classroom. Future work should continue to examine the influence of individual activities on student learning and behaviors, particularly when objective measures of learning, such as quizzes and exams, are held constant.

Journal ArticleDOI
TL;DR: In this paper, the authors present the U.S. Geological Survey Southwest Climate Science Center (SWCSC) and National Science Foundation (NSF) as well as the NOAA Climate Assessment for the Southwest.
Abstract: Colorado Water Institute, National Science Foundation; NOAA Climate Assessment for the Southwest; U.S. Geological Survey Southwest Climate Science Center

Journal ArticleDOI
TL;DR: In this article, the authors explore the evolution of defense hormone signaling networks by combining the model plant-based knowledge about molecular components mediating phytohormone signaling and cross talk with available genome information of other plant species.
Abstract: Studies with model plants such as Arabidopsis thaliana have revealed that phytohormones are central regulators of plant defense. The intricate network of phytohormone signaling pathways enables plants to activate appropriate and effective defense responses against pathogens as well as to balance defense and growth. The timing of the evolution of most phytohormone signaling pathways seems to coincide with the colonization of land, a likely requirement for plant adaptations to the more variable terrestrial environments, which included the presence of pathogens. In this review, we explore the evolution of defense hormone signaling networks by combining the model plant-based knowledge about molecular components mediating phytohormone signaling and cross talk with available genome information of other plant species. We highlight conserved hubs in hormone cross talk and discuss evolutionary advantages of defense hormone cross talk. Finally, we examine possibilities of engineering hormone cross talk for improvement of plant fitness and crop production.

Journal ArticleDOI
TL;DR: This work identifies a complex, nutrient-rich organic coating on co-composted biochar that covers the outer and inner (pore) surfaces of biochar particles using high-resolution spectro(micro)scopy and mass spectrometry, which strengthens biochar-water interactions and thus enhances nutrient retention.
Abstract: Amending soil with biochar (pyrolized biomass) is suggested as a globally applicable approach to address climate change and soil degradation by carbon sequestration, reducing soil-borne greenhouse-gas emissions and increasing soil nutrient retention. Biochar was shown to promote plant growth, especially when combined with nutrient-rich organic matter, e.g., co-composted biochar. Plant growth promotion was explained by slow release of nutrients, although a mechanistic understanding of nutrient storage in biochar is missing. Here we identify a complex, nutrient-rich organic coating on co-composted biochar that covers the outer and inner (pore) surfaces of biochar particles using high-resolution spectro(micro)scopy and mass spectrometry. Fast field cycling nuclear magnetic resonance, electrochemical analysis and gas adsorption demonstrated that this coating adds hydrophilicity, redox-active moieties, and additional mesoporosity, which strengthens biochar-water interactions and thus enhances nutrient retention. This implies that the functioning of biochar in soil is determined by the formation of an organic coating, rather than biochar surface oxidation, as previously suggested. Biochar promotes plant growth via a slow release of nutrients; however, a mechanistic understanding of nutrient storage in biochar is lacking. Here, using high-resolution spectromicroscopy and mass spectrometry, the authors identify an organic coating on co-composted particles that enhances nutrient retention.

Journal ArticleDOI
TL;DR: Evidence, research needs, and discrepancies between top-down and bottom-up approaches used to estimate SOA from motor vehicles are summarized, focusing on inconsistencies between molecular-level understanding and regional observations.
Abstract: Secondary organic aerosol (SOA) is formed from the atmospheric oxidation of gas-phase organic compounds leading to the formation of particle mass. Gasoline- and diesel-powered motor vehicles, both on/off-road, are important sources of SOA precursors. They emit complex mixtures of gas-phase organic compounds that vary in volatility and molecular structure—factors that influence their contributions to urban SOA. However, the relative importance of each vehicle type with respect to SOA formation remains unclear due to conflicting evidence from recent laboratory, field, and modeling studies. Both are likely important, with evolving contributions that vary with location and over short time scales. This review summarizes evidence, research needs, and discrepancies between top-down and bottom-up approaches used to estimate SOA from motor vehicles, focusing on inconsistencies between molecular-level understanding and regional observations. The effect of emission controls (e.g., exhaust aftertreatment technologies...

Journal ArticleDOI
13 Oct 2017-Science
TL;DR: The heterogeneous climate forcing and carbon response over the three tropical continents to the 2015–2016 El Niño challenges previous studies that suggested that a single dominant process determines carbon cycle interannual variability.
Abstract: INTRODUCTION The influence of El Nino on climate is accompanied by large changes to the carbon cycle, and El Nino–induced variability in the carbon cycle has been attributed mainly to the tropical continents. However, owing to a dearth of observations in the tropics, tropical carbon fluxes are poorly quantified, and considerable debate exists over the dominant mechanisms (e.g., plant growth, respiration, fire) and regions (e.g., humid versus semiarid tropics) on the net carbon balance. RATIONALE The launch of the Orbiting Carbon Observatory-2 (OCO-2) shortly before the 2015–2016 El Nino, the second strongest since the 1950s, has provided an opportunity to understand how tropical land carbon fluxes respond to the warm and dry climate characteristics of El Nino conditions. The El Nino events may also provide a natural experiment to study the response of tropical land carbon fluxes to future climate changes, because anomalously warm and dry tropical environments typical of El Nino are expected to be more frequent under most emission scenarios. RESULTS The tropical regions of three continents (South America, Asia, and Africa) had heterogeneous responses to the 2015–2016 El Nino, in terms of both climate drivers and the carbon cycle. The annual mean precipitation over tropical South America and tropical Asia was lower by 3.0σ and 2.8σ, respectively, in 2015 relative to the 2011 La Nina year. Tropical Africa, on the other hand, had near equal precipitation and the same number of dry months between 2015 and 2011; however, surface temperatures were higher by 1.6σ, dominated by the positive anomaly over its eastern and southern regions. In response to the warmer and drier climate anomaly in 2015, the pantropical biosphere released 2.5 ± 0.34 gigatons more carbon into the atmosphere than in 2011, which accounts for 83.3% of the global total 3.0–gigatons of carbon (gigatons C) net biosphere flux differences and 92.6% of the atmospheric CO 2 growth-rate differences between 2015 and 2011. It indicates that the tropical land biosphere flux anomaly was the driver of the highest atmospheric CO 2 growth rate in 2015. The three tropical continents had an approximately even contribution to the pantropical net carbon flux anomaly in 2015, but had diverse dominant processes: gross primary production (GPP) reduced carbon uptake (0.9 ± 0.96 gigatons C) in tropical South America, fire increased carbon release (0.4 ± 0.08 gigatons C) in tropical Asia, and respiration increased carbon release (0.6 ± 1.01 gigatons C) in Africa. We found that most of the excess carbon release in 2015 was associated with either extremely low precipitation or high temperatures, or both. CONCLUSION Our results indicate that the global El Nino effect is a superposition of regionally specific effects. The heterogeneous climate forcing and carbon response over the three tropical continents to the 2015–2016 El Nino challenges previous studies that suggested that a single dominant process determines carbon cycle interannual variability, which could also be due to previous disturbance and soil and vegetation structure. The similarity between the 2015 tropical climate anomaly and the projected climate changes imply that the role of the tropical land as a buffer for fossil fuel emissions may be reduced in the future. The heterogeneous response may reflect differences in temperature and rainfall anomalies, but intrinsic differences in vegetation species, soils, and prior disturbance may contribute as well. A synergistic use of multiple satellite observations and a long time series of spatially resolved fluxes derived from sustained satellite observations will enable tests of these hypotheses, allow for a more process-based understanding, and, ultimately, aid improved carbon-climate model projections.