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Showing papers by "University of Massachusetts Boston published in 2019"


Journal ArticleDOI
TL;DR: Efforts have been put to improve efficiency, flexibility, support for 'big data' (R's long vectors), ease of use and quality check before a new release of ape.
Abstract: Summary After more than fifteen years of existence, the R package ape has continuously grown its contents, and has been used by a growing community of users The release of version 50 has marked a leap towards a modern software for evolutionary analyses Efforts have been put to improve efficiency, flexibility, support for 'big data' (R's long vectors), ease of use and quality check before a new release These changes will hopefully make ape a useful software for the study of biodiversity and evolution in a context of increasing data quantity Availability and implementation ape is distributed through the Comprehensive R Archive Network: http://cranr-projectorg/package=ape Further information may be found at http://ape-packageirdfr/

4,303 citations


Journal ArticleDOI
Kazunori Akiyama, Antxon Alberdi1, Walter Alef2, Keiichi Asada3  +403 moreInstitutions (82)
TL;DR: In this article, the Event Horizon Telescope was used to reconstruct event-horizon-scale images of the supermassive black hole candidate in the center of the giant elliptical galaxy M87.
Abstract: When surrounded by a transparent emission region, black holes are expected to reveal a dark shadow caused by gravitational light bending and photon capture at the event horizon. To image and study this phenomenon, we have assembled the Event Horizon Telescope, a global very long baseline interferometry array observing at a wavelength of 1.3 mm. This allows us to reconstruct event-horizon-scale images of the supermassive black hole candidate in the center of the giant elliptical galaxy M87. We have resolved the central compact radio source as an asymmetric bright emission ring with a diameter of 42 +/- 3 mu as, which is circular and encompasses a central depression in brightness with a flux ratio greater than or similar to 10: 1. The emission ring is recovered using different calibration and imaging schemes, with its diameter and width remaining stable over four different observations carried out in different days. Overall, the observed image is consistent with expectations for the shadow of a Kerr black hole as predicted by general relativity. The asymmetry in brightness in the ring can be explained in terms of relativistic beaming of the emission from a plasma rotating close to the speed of light around a black hole. We compare our images to an extensive library of ray-traced general-relativistic magnetohydrodynamic simulations of black holes and derive a central mass of M = (6.5 +/- 0.7) x 10(9) M-circle dot. Our radio-wave observations thus provide powerful evidence for the presence of supermassive black holes in centers of galaxies and as the central engines of active galactic nuclei. They also present a new tool to explore gravity in its most extreme limit and on a mass scale that was so far not accessible.

2,589 citations


Journal ArticleDOI
Kazunori Akiyama, Antxon Alberdi1, Walter Alef2, Keiichi Asada3  +251 moreInstitutions (56)
TL;DR: In this article, the authors present measurements of the properties of the central radio source in M87 using Event Horizon Telescope data obtained during the 2017 campaign, and find that >50% of the total flux at arcsecond scales comes from near the horizon and that the emission is dramatically suppressed interior to this region by a factor >10, providing direct evidence of the predicted shadow of a black hole.
Abstract: We present measurements of the properties of the central radio source in M87 using Event Horizon Telescope data obtained during the 2017 campaign. We develop and fit geometric crescent models (asymmetric rings with interior brightness depressions) using two independent sampling algorithms that consider distinct representations of the visibility data. We show that the crescent family of models is statistically preferred over other comparably complex geometric models that we explore. We calibrate the geometric model parameters using general relativistic magnetohydrodynamic (GRMHD) models of the emission region and estimate physical properties of the source. We further fit images generated from GRMHD models directly to the data. We compare the derived emission region and black hole parameters from these analyses with those recovered from reconstructed images. There is a remarkable consistency among all methods and data sets. We find that >50% of the total flux at arcsecond scales comes from near the horizon, and that the emission is dramatically suppressed interior to this region by a factor >10, providing direct evidence of the predicted shadow of a black hole. Across all methods, we measure a crescent diameter of 42 ± 3 μas and constrain its fractional width to be <0.5. Associating the crescent feature with the emission surrounding the black hole shadow, we infer an angular gravitational radius of GM/Dc2 = 3.8 ± 0.4 μas. Folding in a distance measurement of ${16.8}_{-0.7}^{+0.8}\,\mathrm{Mpc}$ gives a black hole mass of $M=6.5\pm 0.2{| }_{\mathrm{stat}}\pm 0.7{| }_{\mathrm{sys}}\times {10}^{9}\hspace{2pt}{M}_{\odot }$. This measurement from lensed emission near the event horizon is consistent with the presence of a central Kerr black hole, as predicted by the general theory of relativity.

1,024 citations


Journal ArticleDOI
Kazunori Akiyama, Antxon Alberdi1, Walter Alef2, Keiichi Asada3  +251 moreInstitutions (58)
TL;DR: In this article, the first Event Horizon Telescope (EHT) images of M87 were presented, using observations from April 2017 at 1.3 mm wavelength, showing a prominent ring with a diameter of ~40 μas, consistent with the size and shape of the lensed photon orbit encircling the "shadow" of a supermassive black hole.
Abstract: We present the first Event Horizon Telescope (EHT) images of M87, using observations from April 2017 at 1.3 mm wavelength. These images show a prominent ring with a diameter of ~40 μas, consistent with the size and shape of the lensed photon orbit encircling the "shadow" of a supermassive black hole. The ring is persistent across four observing nights and shows enhanced brightness in the south. To assess the reliability of these results, we implemented a two-stage imaging procedure. In the first stage, four teams, each blind to the others' work, produced images of M87 using both an established method (CLEAN) and a newer technique (regularized maximum likelihood). This stage allowed us to avoid shared human bias and to assess common features among independent reconstructions. In the second stage, we reconstructed synthetic data from a large survey of imaging parameters and then compared the results with the corresponding ground truth images. This stage allowed us to select parameters objectively to use when reconstructing images of M87. Across all tests in both stages, the ring diameter and asymmetry remained stable, insensitive to the choice of imaging technique. We describe the EHT imaging procedures, the primary image features in M87, and the dependence of these features on imaging assumptions.

952 citations


Journal ArticleDOI
Kazunori Akiyama, Antxon Alberdi1, Walter Alef2, Keiichi Asada3  +259 moreInstitutions (62)
TL;DR: In this article, a large library of models based on general relativistic magnetohydrodynamic (GRMHD) simulations and synthetic images produced by GRS was constructed and compared with the observed visibilities.
Abstract: The Event Horizon Telescope (EHT) has mapped the central compact radio source of the elliptical galaxy M87 at 1.3 mm with unprecedented angular resolution. Here we consider the physical implications of the asymmetric ring seen in the 2017 EHT data. To this end, we construct a large library of models based on general relativistic magnetohydrodynamic (GRMHD) simulations and synthetic images produced by general relativistic ray tracing. We compare the observed visibilities with this library and confirm that the asymmetric ring is consistent with earlier predictions of strong gravitational lensing of synchrotron emission from a hot plasma orbiting near the black hole event horizon. The ring radius and ring asymmetry depend on black hole mass and spin, respectively, and both are therefore expected to be stable when observed in future EHT campaigns. Overall, the observed image is consistent with expectations for the shadow of a spinning Kerr black hole as predicted by general relativity. If the black hole spin and M87's large scale jet are aligned, then the black hole spin vector is pointed away from Earth. Models in our library of non-spinning black holes are inconsistent with the observations as they do not produce sufficiently powerful jets. At the same time, in those models that produce a sufficiently powerful jet, the latter is powered by extraction of black hole spin energy through mechanisms akin to the Blandford-Znajek process. We briefly consider alternatives to a black hole for the central compact object. Analysis of existing EHT polarization data and data taken simultaneously at other wavelengths will soon enable new tests of the GRMHD models, as will future EHT campaigns at 230 and 345 GHz.

808 citations


Journal ArticleDOI
Kazunori Akiyama, Antxon Alberdi1, Walter Alef2, Keiichi Asada3  +394 moreInstitutions (78)
TL;DR: The Event Horizon Telescope (EHT) as mentioned in this paper is a very long baseline interferometry (VLBI) array that comprises millimeter and submillimeter-wavelength telescopes separated by distances comparable to the diameter of the Earth.
Abstract: The Event Horizon Telescope (EHT) is a very long baseline interferometry (VLBI) array that comprises millimeter- and submillimeter-wavelength telescopes separated by distances comparable to the diameter of the Earth. At a nominal operating wavelength of ~1.3 mm, EHT angular resolution (λ/D) is ~25 μas, which is sufficient to resolve nearby supermassive black hole candidates on spatial and temporal scales that correspond to their event horizons. With this capability, the EHT scientific goals are to probe general relativistic effects in the strong-field regime and to study accretion and relativistic jet formation near the black hole boundary. In this Letter we describe the system design of the EHT, detail the technology and instrumentation that enable observations, and provide measures of its performance. Meeting the EHT science objectives has required several key developments that have facilitated the robust extension of the VLBI technique to EHT observing wavelengths and the production of instrumentation that can be deployed on a heterogeneous array of existing telescopes and facilities. To meet sensitivity requirements, high-bandwidth digital systems were developed that process data at rates of 64 gigabit s^(−1), exceeding those of currently operating cm-wavelength VLBI arrays by more than an order of magnitude. Associated improvements include the development of phasing systems at array facilities, new receiver installation at several sites, and the deployment of hydrogen maser frequency standards to ensure coherent data capture across the array. These efforts led to the coordination and execution of the first Global EHT observations in 2017 April, and to event-horizon-scale imaging of the supermassive black hole candidate in M87.

756 citations


Journal ArticleDOI
Kazunori Akiyama, Antxon Alberdi1, Walter Alef2, Keiichi Asada3  +243 moreInstitutions (60)
TL;DR: In this paper, the Event Horizon Telescope (EHT) 1.3 mm radio wavelength observations of the supermassive black hole candidate at the center of the radio galaxy M87 and the quasar 3C 279, taken during the 2017 April 5-11 observing campaign are presented.
Abstract: We present the calibration and reduction of Event Horizon Telescope (EHT) 1.3 mm radio wavelength observations of the supermassive black hole candidate at the center of the radio galaxy M87 and the quasar 3C 279, taken during the 2017 April 5–11 observing campaign. These global very long baseline interferometric observations include for the first time the highly sensitive Atacama Large Millimeter/submillimeter Array (ALMA); reaching an angular resolution of 25 μas, with characteristic sensitivity limits of ~1 mJy on baselines to ALMA and ~10 mJy on other baselines. The observations present challenges for existing data processing tools, arising from the rapid atmospheric phase fluctuations, wide recording bandwidth, and highly heterogeneous array. In response, we developed three independent pipelines for phase calibration and fringe detection, each tailored to the specific needs of the EHT. The final data products include calibrated total intensity amplitude and phase information. They are validated through a series of quality assurance tests that show consistency across pipelines and set limits on baseline systematic errors of 2% in amplitude and 1° in phase. The M87 data reveal the presence of two nulls in correlated flux density at ~3.4 and ~8.3 Gλ and temporal evolution in closure quantities, indicating intrinsic variability of compact structure on a timescale of days, or several light-crossing times for a few billion solar-mass black hole. These measurements provide the first opportunity to image horizon-scale structure in M87.

625 citations


Journal ArticleDOI
TL;DR: The programmatic developments and institutional context for the Landsat program and the unique ability of Landsat to meet the needs of national and international programs are described and the key trends in Landsat science are presented.

524 citations


Journal ArticleDOI
Donald J. Hagler1, Sean N. Hatton1, M. Daniela Cornejo1, Carolina Makowski2, Damien A. Fair3, Anthony Steven Dick4, Matthew T. Sutherland4, B. J. Casey5, M Deanna6, Michael P. Harms6, Richard Watts5, James M. Bjork7, Hugh Garavan8, Laura Hilmer1, Christopher J. Pung1, Chelsea S. Sicat1, Joshua M. Kuperman1, Hauke Bartsch1, Feng Xue1, Mary M. Heitzeg9, Angela R. Laird4, Thanh T. Trinh1, Raul Gonzalez4, Susan F. Tapert1, Michael C. Riedel4, Lindsay M. Squeglia10, Luke W. Hyde9, Monica D. Rosenberg5, Eric Earl3, Katia D. Howlett11, Fiona C. Baker12, Mary E. Soules9, Jazmin Diaz1, Octavio Ruiz de Leon1, Wesley K. Thompson1, Michael C. Neale7, Megan M. Herting13, Elizabeth R. Sowell13, Ruben P. Alvarez11, Samuel W. Hawes4, Mariana Sanchez4, Jerzy Bodurka14, Florence J. Breslin14, Amanda Sheffield Morris14, Martin P. Paulus14, W. Kyle Simmons14, Jonathan R. Polimeni15, Andre van der Kouwe15, Andrew S. Nencka16, Kevin M. Gray10, Carlo Pierpaoli11, John A. Matochik11, Antonio Noronha11, Will M. Aklin11, Kevin P. Conway11, Meyer D. Glantz11, Elizabeth Hoffman11, Roger Little11, Marsha F. Lopez11, Vani Pariyadath11, Susan R.B. Weiss11, Dana L. Wolff-Hughes, Rebecca DelCarmen-Wiggins, Sarah W. Feldstein Ewing3, Oscar Miranda-Dominguez3, Bonnie J. Nagel3, Anders Perrone3, Darrick Sturgeon3, Aimee Goldstone12, Adolf Pfefferbaum12, Kilian M. Pohl12, Devin Prouty12, Kristina A. Uban17, Susan Y. Bookheimer18, Mirella Dapretto18, Adriana Galván18, Kara Bagot1, Jay N. Giedd1, M. Alejandra Infante1, Joanna Jacobus1, Kevin Patrick1, Paul D. Shilling1, Rahul S. Desikan19, Yi Li19, Leo P. Sugrue19, Marie T. Banich20, Naomi P. Friedman20, John K. Hewitt20, Christian J. Hopfer20, Joseph T. Sakai20, Jody Tanabe20, Linda B. Cottler21, Sara Jo Nixon21, Linda Chang22, Christine C. Cloak22, Thomas Ernst22, Gloria Reeves22, David N. Kennedy23, Steve Heeringa9, Scott Peltier9, John E. Schulenberg9, Chandra Sripada9, Robert A. Zucker9, William G. Iacono24, Monica Luciana24, Finnegan J. Calabro25, Duncan B. Clark25, David A. Lewis25, Beatriz Luna25, Claudiu Schirda25, Tufikameni Brima26, John J. Foxe26, Edward G. Freedman26, Daniel W. Mruzek26, Michael J. Mason27, Rebekah S. Huber28, Erin McGlade28, Andrew P. Prescot28, Perry F. Renshaw28, Deborah A. Yurgelun-Todd28, Nicholas Allgaier8, Julie A. Dumas8, Masha Y. Ivanova8, Alexandra Potter8, Paul Florsheim29, Christine L. Larson29, Krista M. Lisdahl29, Michael E. Charness30, Michael E. Charness31, Michael E. Charness15, Bernard F. Fuemmeler7, John M. Hettema7, Hermine H. Maes7, Joel L. Steinberg7, Andrey P. Anokhin6, Paul E.A. Glaser6, Andrew C. Heath6, Pamela A. F. Madden6, Arielle R. Baskin-Sommers5, R. Todd Constable5, Steven Grant11, Gayathri J. Dowling11, Sandra A. Brown1, Terry L. Jernigan1, Anders M. Dale1 
TL;DR: The baseline neuroimaging processing and subject-level analysis methods used by the Adolescent Brain Cognitive Development Study are described to be a resource of unprecedented scale and depth for studying typical and atypical development.

431 citations


Journal ArticleDOI
TL;DR: The findings suggest that mistreatment is experienced more frequently by women of colour, when birth occurs in hospitals, and among those with social, economic or health challenges, and by patient-provider disagreements.
Abstract: Recently WHO researchers described seven dimensions of mistreatment in maternity care that have adverse impacts on quality and safety. Applying the WHO framework for quality care, service users partnered with NGOs, clinicians, and researchers, to design and conduct the Giving Voice to Mothers (GVtM)–US study. Our multi-stakeholder team distributed an online cross-sectional survey to capture lived experiences of maternity care in diverse populations. Patient-designed items included indicators of verbal and physical abuse, autonomy, discrimination, failure to meet professional standards of care, poor rapport with providers, and poor conditions in the health system. We quantified the prevalence of mistreatment by race, socio-demographics, mode of birth, place of birth, and context of care, and describe the intersectional relationships between these variables. Of eligible participants (n = 2700), 2138 completed all sections of the survey. One in six women (17.3%) reported experiencing one or more types of mistreatment such as: loss of autonomy; being shouted at, scolded, or threatened; and being ignored, refused, or receiving no response to requests for help. Context of care (e.g. mode of birth; transfer; difference of opinion) correlated with increased reports of mistreatment. Experiences of mistreatment differed significantly by place of birth: 5.1% of women who gave birth at home versus 28.1% of women who gave birth at the hospital. Factors associated with a lower likelihood of mistreatment included having a vaginal birth, a community birth, a midwife, and being white, multiparous, and older than 30 years. Rates of mistreatment for women of colour were consistently higher even when examining interactions between race and other maternal characteristics. For example, 27.2% of women of colour with low SES reported any mistreatment versus 18.7% of white women with low SES. Regardless of maternal race, having a partner who was Black also increased reported mistreatment. This is the first study to use indicators developed by service users to describe mistreatment in childbirth in the US. Our findings suggest that mistreatment is experienced more frequently by women of colour, when birth occurs in hospitals, and among those with social, economic or health challenges. Mistreatment is exacerbated by unexpected obstetric interventions, and by patient-provider disagreements.

338 citations


Journal ArticleDOI
18 Oct 2019-Science
TL;DR: Examining spatial variation in species richness and composition change using more than 50,000 biodiversity time series from 239 studies found clear geographic variation in biodiversity change, suggesting that biodiversity change may be spatially structured.
Abstract: Human activities are fundamentally altering biodiversity. Projections of declines at the global scale are contrasted by highly variable trends at local scales, suggesting that biodiversity change may be spatially structured. Here, we examined spatial variation in species richness and composition change using more than 50,000 biodiversity time series from 239 studies and found clear geographic variation in biodiversity change. Rapid compositional change is prevalent, with marine biomes exceeding and terrestrial biomes trailing the overall trend. Assemblage richness is not changing on average, although locations exhibiting increasing and decreasing trends of up to about 20% per year were found in some marine studies. At local scales, widespread compositional reorganization is most often decoupled from richness change, and biodiversity change is strongest and most variable in the oceans.

Journal ArticleDOI
TL;DR: The United States (U.S.) federal government provides imagery obtained by federally funded Earth Observation satellites typically at no cost, until 2008 when the United States Geological Survey (USGS) made Landsat data accessible via the internet for free as mentioned in this paper.

Journal ArticleDOI
06 Aug 2019-JAMA
TL;DR: The USPSTF reaffirms its previous conclusion that the potential benefits of screening for pancreatic cancer in asymptomatic adults do not outweigh the potential harms.
Abstract: Importance Pancreatic cancer is an uncommon cancer with an age-adjusted annual incidence of 12.9 cases per 100 000 person-years. However, the death rate is 11.0 deaths per 100 000 person-years because the prognosis of pancreatic cancer is poor. Although its incidence is low, pancreatic cancer is the third most common cause of cancer death in the United States. Because of the increasing incidence of pancreatic cancer, along with improvements in early detection and treatment of other types of cancer, it is estimated that pancreatic cancer may soon become the second-leading cause of cancer death in the United States. Objective To update the 2004 US Preventive Services Task Force (USPSTF) recommendation on screening for pancreatic cancer. Evidence Review The USPSTF reviewed the evidence on the benefits and harms of screening for pancreatic cancer, the diagnostic accuracy of screening tests for pancreatic cancer, and the benefits and harms of treatment of screen-detected or asymptomatic pancreatic cancer. Findings The USPSTF found no evidence that screening for pancreatic cancer or treatment of screen-detected pancreatic cancer improves disease-specific morbidity or mortality, or all-cause mortality. The USPSTF found adequate evidence that the magnitude of the benefits of screening for pancreatic cancer in asymptomatic adults can be bounded as no greater than small. The USPSTF found adequate evidence that the magnitude of the harms of screening for pancreatic cancer and treatment of screen-detected pancreatic cancer can be bounded as at least moderate. The USPSTF reaffirms its previous conclusion that the potential benefits of screening for pancreatic cancer in asymptomatic adults do not outweigh the potential harms. Conclusions and Recommendation The USPSTF recommends against screening for pancreatic cancer in asymptomatic adults. (D recommendation)

Journal ArticleDOI
TL;DR: This review article highlights the Ugi, Groebke-Blackburn-Bienaymé, Biginelli, Huisgen, Petasis, Gewald, and Asinger reaction-initiated consecutive MCRs.
Abstract: Multicomponent reactions (MCRs) involving a minimum of three reactants or reaction centers are conducted in one pot and with a single operational step This synthetic method has a good pot, atom and step economy in the preparation of diverse and complex molecular scaffolds Consecutive MCRs, also known as sequential or multiple MCRs, by combining two or more MCRs, exhibit even higher synthetic efficiency, product structural diversity, and molecular complexity This review article highlights the Ugi, Groebke-Blackburn-Bienayme, Biginelli, Huisgen, Petasis, Gewald, and Asinger reaction-initiated consecutive MCRs

Journal ArticleDOI
TL;DR: A comprehensive meta-analysis of all outcome studies of intergenerational, one-on-one youth mentoring programs written in the English language between 1975 and 2017 provides some support for the efficacy of mentoring interventions, while also emphasizing the need to remain realistic about the modest impact of these programs.
Abstract: Mentoring programs, which pair youth with caring, non-parental adults with the goal of promoting positive youth development, are an increasingly popular strategy for early intervention with at-risk youth. However, important questions remain about the extent to which these interventions improve youth outcomes. The present study involved a comprehensive meta-analysis of all outcome studies of intergenerational, one-on-one youth mentoring programs written in the English language between 1975 and 2017, using rigorous inclusion criteria designed to align with developmental theories of youth mentoring. Analysis of 70 mentoring outcome studies, with a sample size of 25,286 youth (average age of 12 years old), yielded a statistically significant effect of mentoring programs across all youth outcomes. The observed effect size fell within the medium/moderate range according to empirical guidelines derived from universal prevention programs for youth, and was consistent with past meta-analyses of youth mentoring. Moderation analyses indicated that programs serving a larger proportion of male youth, deploying a greater percentage of male mentors or mentors with a helping profession background, and requiring shorter meetings yielded larger effect sizes, as did evaluations that relied on questionnaires and youth self-report. Taken together, these findings provide some support for the efficacy of mentoring interventions, while also emphasizing the need to remain realistic about the modest impact of these programs as currently implemented, and highlighting opportunities for improving the quality and rigor of mentoring practices.

Journal ArticleDOI
Roy Burstein1, Nathaniel J Henry1, Michael Collison1, Laurie B. Marczak1  +663 moreInstitutions (290)
16 Oct 2019-Nature
TL;DR: A high-resolution, global atlas of mortality of children under five years of age between 2000 and 2017 highlights subnational geographical inequalities in the distribution, rates and absolute counts of child deaths by age.
Abstract: Since 2000, many countries have achieved considerable success in improving child survival, but localized progress remains unclear. To inform efforts towards United Nations Sustainable Development Goal 3.2—to end preventable child deaths by 2030—we need consistently estimated data at the subnational level regarding child mortality rates and trends. Here we quantified, for the period 2000–2017, the subnational variation in mortality rates and number of deaths of neonates, infants and children under 5 years of age within 99 low- and middle-income countries using a geostatistical survival model. We estimated that 32% of children under 5 in these countries lived in districts that had attained rates of 25 or fewer child deaths per 1,000 live births by 2017, and that 58% of child deaths between 2000 and 2017 in these countries could have been averted in the absence of geographical inequality. This study enables the identification of high-mortality clusters, patterns of progress and geographical inequalities to inform appropriate investments and implementations that will help to improve the health of all populations.

Journal ArticleDOI
TL;DR: This Perspective article provides a research agenda and roadmap for future research aimed at advancing the understanding of the interplay between ecology and evolution of urban‐dwelling organisms and identifies six key questions that would significantly increase understanding of how urbanization influences evolutionary processes.
Abstract: Urban ecosystems are rapidly expanding throughout the world, but how urban growth affects the evolutionary ecology of species living in urban areas remains largely unknown. Urban ecology has advanced our understanding of how the development of cities and towns change environmental conditions and alter ecological processes and patterns. However, despite decades of research in urban ecology, the extent to which urbanization influences evolutionary and eco-evolutionary change has received little attention. The nascent field of urban evolutionary ecology seeks to understand how urbanization affects the evolution of populations, and how those evolutionary changes in turn influence the ecological dynamics of populations, communities, and ecosystems. Following a brief history of this emerging field, this Perspective article provides a research agenda and roadmap for future research aimed at advancing our understanding of the interplay between ecology and evolution of urban-dwelling organisms. We identify six key questions that, if addressed, would significantly increase our understanding of how urbanization influences evolutionary processes. These questions consider how urbanization affects nonadaptive evolution, natural selection, and convergent evolution, in addition to the role of urban environmental heterogeneity on species evolution, and the roles of phenotypic plasticity versus adaptation on species' abundance in cities. Our final question examines the impact of urbanization on evolutionary diversification. For each of these six questions, we suggest avenues for future research that will help advance the field of urban evolutionary ecology. Lastly, we highlight the importance of integrating urban evolutionary ecology into urban planning, conservation practice, pest management, and public engagement.

Journal ArticleDOI
TL;DR: In this paper, the authors present a consensus assessment and recommendations on the current state of and opportunities for advancing global marine macrophyte observations, integrating contributions from a community of researchers with broad geographic and disciplinary expertise.
Abstract: In coastal waters around the world, the dominant primary producers are benthic macrophytes, including seagrasses and macroalgae, that provide habitat structure and food for diverse and abundant biological communities and drive ecosystem processes. Seagrass meadows and macroalgal forests play key roles for coastal societies, contributing to fishery yields, storm protection, biogeochemical cycling and storage, and important cultural values. These socio-economically valuable services are threatened worldwide by human activities, with substantial areas of seagrass and macroalgal forests lost over the last half-century. Tracking the status and trends in marine macrophyte cover and quality is an emerging priority for ocean and coastal management, but doing so has been challenged by limited coordination across the numerous efforts to monitor macrophytes, which vary widely in goals, methodologies, scales, capacity, governance approaches, and data availability. Here, we present a consensus assessment and recommendations on the current state of and opportunities for advancing global marine macrophyte observations, integrating contributions from a community of researchers with broad geographic and disciplinary expertise. With the increasing scale of human impacts, the time is ripe to harmonize marine macrophyte observations by building on existing networks and identifying a core set of common metrics and approaches in sampling design, field measurements, governance, capacity building, and data management. We recommend a tiered observation system, with improvement of remote sensing and remote underwater imaging to expand capacity to capture broad-scale extent at intervals of several years, coordinated with stratified in situ sampling annually to characterize the key variables of cover and taxonomic or functional group composition, and to provide ground-truth. A robust networked system of macrophyte observations will be facilitated by establishing best practices, including standard protocols, documentation, and sharing of resources at all stages of workflow, and secure archiving of open-access data. Because such a network is necessarily distributed, sustaining it depends on close engagement of local stakeholders and focusing on building and long-term maintenance of local capacity, particularly in the developing world. Realizing these recommendations will produce more effective, efficient, and responsive observing, a more accurate global picture of change in vegetated coastal systems, and stronger international capacity for sustaining observations.

Journal ArticleDOI
TL;DR: For example, Lockwood et al. as mentioned in this paper synthesize information across taxa and research disciplines to document the exotic pet trade's contribution to vertebrate biological invasions, and show recent and substantial worldwide growth in the number of non-native animal populations introduced via this invasion pathway, which demonstrates a strong potential to increase the numbers of invasive animals in the future.
Abstract: Author(s): Lockwood, JL; Welbourne, DJ; Romagosa, CM; Cassey, P; Mandrak, NE; Strecker, A; Leung, B; Stringham, OC; Udell, B; Episcopio-Sturgeon, DJ; Tlusty, MF; Sinclair, J; Springborn, MR; Pienaar, EF; Rhyne, AL; Keller, R | Abstract: The annual trade in exotic vertebrates as pets is a multi-billion-dollar global business. Thousands of species, and tens of millions of individual animals, are shipped both internationally and within countries to satisfy this demand. Most research on the exotic pet trade has focused on its contribution to native biodiversity loss and disease spread. Here, we synthesize information across taxa and research disciplines to document the exotic pet trade's contribution to vertebrate biological invasions. We show recent and substantial worldwide growth in the number of non-native animal populations introduced via this invasion pathway, which demonstrates a strong potential to increase the number of invasive animals in the future. Key to addressing the invasion threat of exotic pets is learning more about the socioeconomic forces that drive the massive growth in the exotic pet market and the socioecological factors that underlie pet release by owners. These factors likely vary according to cultural pet-keeping traditions across regions and whether purchases were legal or illegal. These gaps in our understanding of the exotic pet trade must be addressed in order to implement effective policy solutions.


Journal ArticleDOI
TL;DR: An energy theft detection scheme with energy privacy preservation in the smart grid using combined convolutional neural networks (CNNs) to detect abnormal behavior of the metering data from a long-period pattern observation and employing Paillier algorithm to protect the energy privacy.
Abstract: As a prominent early instance of the Internet of Things in the smart grid, the advanced metering infrastructure (AMI) provides real-time information from smart meters to both grid operators and customers, exploiting the full potential of demand response. However, the newly collected information without security protection can be maliciously altered and result in huge loss. In this paper, we propose an energy theft detection scheme with energy privacy preservation in the smart grid. Especially, we use combined convolutional neural networks (CNNs) to detect abnormal behavior of the metering data from a long-period pattern observation. In addition, we employ Paillier algorithm to protect the energy privacy. In other words, the users’ energy data are securely protected in the transmission and the data disclosure is minimized. Our security analysis demonstrates that in our scheme data privacy and authentication are both achieved. Experimental results illustrate that our modified CNN model can effectively detect abnormal behaviors at an accuracy up to 92.67%.

Journal ArticleDOI
TL;DR: In this article, an optically pumped GeSn laser based on both ridge and planar waveguide structures was demonstrated for near room temperature operation at 270 K with edge-emitting devices.
Abstract: Lasing from direct bandgap group-IV GeSn alloys has opened a new venue for the development of Si-based monolithic laser. In this work, we demonstrate optically pumped GeSn lasers based on both ridge and planar waveguide structures. The near room temperature operation at 270 K was achieved with optically pumped edge-emitting devices. Moreover, due to the reduced side-wall surface recombination and improved thermal management, the 100 μm wide ridge waveguide laser features a lower lasing threshold compared to other devices. The advance reported in this work, enabled by the material growth via an industry standard chemical vapor deposition reactor and low-cost commercially available precursors, is a major step forward toward Si-based mid-infrared sources for photonics integration.

Journal ArticleDOI
TL;DR: This digest aims to provide an overview of recent advances in sulfonamide-based bioactive compounds, their importance in drug discovery and development emphasizing multi-target approaches for complex diseases, and their novel contribution to contemporary medicinal chemistry.

Journal ArticleDOI
TL;DR: In this article, the authors examined the role of the consumer's perceived body image in consumer evaluation and intention to adopt AR-based virtual try-on technology and found that consumers who perceived their body image as unfavorable record more favorable evaluations about AR than about traditional Web-based product presentations, while consumers who perceive their body images as favorable record no differences in their responses to the two presentations.

Journal ArticleDOI
TL;DR: Findings detail specific mechanisms by which microplastics threaten corals, but also hint that the coral A. poculata, which has a large coastal range, may serve as a useful bioindicator and monitoring tool for microplastic pollution.
Abstract: Microplastics (less than 5 mm) are a recognized threat to aquatic food webs because they are ingested at multiple trophic levels and may bioaccumulate. In urban coastal environments, high densities...

Journal ArticleDOI
TL;DR: The GeSn detector as discussed by the authors offers high-performance Si-based infrared photodetectors with complementary metal-oxide-semiconductor (CMOS) technique compatibility, which can be used for high-quality IR photodeter.
Abstract: The GeSn detector offers high-performance Si-based infrared photodetectors with complementary metal-oxide-semiconductor (CMOS) technique compatibility. In this work, we report a comprehensive study...

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TL;DR: A study of network efficiency and resilience in response to random and targeted disruptions of ITS systems in 10 urban areas found locking traffic signal states was found to cause more disruption than fully disabling signals.
Abstract: Many cities are adopting increasingly advanced Intelligent Transportation Systems (ITS). These systems combine connectivity, coordination, adaptivity, and automated response for transportation policy optimization, thus increasing “smartness” and efficiency. However, the control and sensing systems of implemented ITS can open new vulnerabilities, especially to cyber-attacks. Currently vulnerability is managed within the framework of traditional risk assessment that assesses potential failures of the system in response to specified threats. Emerging technologies by their nature have threats that are not fully known, therefore, resilience, defined as the system's ability to recover and adapt to both known and unknown threats, is an emerging area that holds promise for assessing threats to ITS. To illustrate the applicability of resilience to ITS, we conducted a study of network efficiency and resilience in response to random and targeted disruptions of ITS systems in 10 urban areas. Disruptions were generated to affect either intersections or roadways controlled by ITS under different threat scenarios. Modeled attacks, under worst case scenarios, disrupted 20% of intersections causing on average 14.6% more additional delays than the same severity attacks on roadways. Additionally, locking traffic signal states was found to cause more disruption than fully disabling signals. Thus, as cities adopt ITS and other smart systems resulting in potentially unknown vulnerabilities, it is important to consider resilience of transportation infrastructure affected by potential cyber-attacks.

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TL;DR: Although there has been progress in supporting transitioning process to non-driving and improving mobility options for older adults following driving cessation, many knowledge gaps still exist and several research topics that would benefit from continued scientific inquiry are identified.
Abstract: Engagement in civic, social, and community life plays an important role in health, well-being, and quality of life, and requires individuals to be mobile in their environment. In this article, we review what is currently known about 2 areas relevant to safe mobility for older drivers and identify future research in these areas. Using a framework for transportation and safe mobility, 2 key areas were selected for review: the process of transitioning to non-driving and the maintenance of mobility after driving has ceased. This article serves as a companion to another article that used the same approach to explore safe mobility issues for older adults who are still driving. We found that although there has been progress in supporting transitioning process to non-driving and improving mobility options for older adults following driving cessation, many knowledge gaps still exist. We identified several research topics that would benefit from continued scientific inquiry. In addition, several themes emerged from the review, including the need for: multidisciplinary, community-wide solutions; large-scale, longitudinal studies; improved education and training for older adults and the variety of stakeholders involved in older adult transportation; and the need for programs and interventions that are flexible and responsive to individual needs and situational differences.

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TL;DR: Frailty was strongly associated with survival and was independent of age, sex, race, and smoking; the VA-FI better predicted mortality than age alone; theVA-FI could be used to more accurately estimate life expectancy and individualize care for Veterans.
Abstract: Background Frailty is a key determinant of clinical outcomes. We sought to describe frailty among U.S. Veterans and its association with mortality. Methods Nationwide retrospective cohort study of regular Veterans Affairs (VA) users, aged at least 65 years in 2002-2012, followed through 2014, using national VA administrative and Medicare and Medicaid data. A frailty index (FI) for VA (VA-FI) was calculated using the cumulative deficit method. Thirty-one age-related deficits in health from diagnostic and procedure codes were included and were updated biennially. Survival analysis assessed associations between VA-FI and mortality. Results A VA-FI was calculated for 2,837,152 Veterans over 10 years. In 2002, 35.5% were non-frail (FI = 0-0.10), 32.6% were pre-frail (FI = 0.11-0.20), 18.9% were mildly frail (FI = 0.21-0.30), 8.7% were moderately frail (FI = 0.31-0.40), and 4.3% were severely frail (FI > 0.40). From 2002 to 2012, the prevalence of moderate frailty increased to 12.7%and severe frailty to 14.1%. Frailty was strongly associated with survival and was independent of age, sex, race, and smoking; the VA-FI better predicted mortality than age alone. Although prevalence of frailty rose over time, compared to non-frail Veterans, 2 years' hazard ratios (95% confidence intervals) for mortality declined from a peak in 2004 of 2.01 (1.97-2.04), 3.49 (3.44-3.55), 5.88 (5.79-5.97), and 10.39 (10.23-10.56) for pre-frail, mildly, moderately, and severely frail, respectively, to 1.51 (1.49-1.53), 2.36 (2.33-2.39), 3.68 (3.63-3.73), 6.62 (6.53-6.71) in 2012. At every frailty level, risk of mortality was lower for women versus men and higher for blacks versus whites. Conclusions Frailty affects at least 3 of every 10 U.S. Veterans aged 65 years and older, and is strongly associated with mortality. The VA-FI could be used to more accurately estimate life expectancy and individualize care for Veterans.

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TL;DR: Wang et al. as discussed by the authors unpack four types of institutional challenges to social entrepreneurship, as perceived by social entrepreneurs: norms of a strong role for government; misunderstood or unknown role for social enterprises; non-supportive rules and regulations; and lack of socio-cultural values and beliefs in support of social goals.
Abstract: We investigate the research question: Why are there very few social enterprises in China? Our findings unpack four types of institutional challenges to social entrepreneurship, as perceived by social entrepreneurs: norms of a strong role for government; misunderstood or unknown role for social enterprises; non-supportive rules and regulations; and lack of socio-cultural values and beliefs in support of social goals. We contribute to the literature on social enterprises by showing how an institutional environment may be “non-munificent,” i.e., non-supportive for the existence of social enterprises and their goals, and we thus address the need for more attention to the institutional environment in which social entrepreneurship takes place. Further, by using Q-methodology on 42 social entrepreneurs along with illustrative qualitative data from interviews, we address the need to go beyond anecdotal case studies and introduce methodological plurality in social entrepreneurship research. Finally, our findings on institutional challenges provide us with an opportunity to discuss how social entrepreneurs may engage with purposive activities to overcome such challenges, leading us to initiate a conversation between the social entrepreneurship and institutional work literatures.