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Showing papers by "Boston College published in 2020"


Journal ArticleDOI
TL;DR: The largest declines in risk exposure from 2010 to 2019 were among a set of risks that are strongly linked to social and economic development, including household air pollution; unsafe water, sanitation, and handwashing; and child growth failure.

3,059 citations


Journal ArticleDOI
TL;DR: This paper showed that stocks with higher ES ratings have significantly higher returns, lower return volatility, and higher operating profit margins during the COVID-19 pandemic and the subsequent lockdown brought about an exogenous and unparalleled stock market crash The crisis thus provides a unique opportunity to test theories of environmental and social policies.
Abstract: The COVID-19 pandemic and the subsequent lockdown brought about an exogenous and unparalleled stock market crash The crisis thus provides a unique opportunity to test theories of environmental and social (ES) policies This paper shows that stocks with higher ES ratings have significantly higher returns, lower return volatility, and higher operating profit margins during the first quarter of 2020 ES firms with higher advertising expenditures experience higher stock returns, and stocks held by more ES-oriented investors experience less return volatility during the crash This paper highlights the importance of customer and investor loyalty to the resiliency of ES stocks

385 citations


Journal ArticleDOI
TL;DR: The collective vision of a group of scholars in vocational psychology who have sought to develop a research agenda in response to the massive global unemployment crisis that has been evoked by the COVID-19 pandemic is described in this paper.

333 citations


Journal ArticleDOI
TL;DR: This article identified four major themes in the literature on platform economy and their consequences for the nature of work and employment, and proposed a framework to identify the major themes of platform economy research.
Abstract: The rapid growth of the platform economy has provoked scholarly discussion of its consequences for the nature of work and employment. We identify four major themes in the literature on platform wor...

311 citations


Journal ArticleDOI
23 Jul 2020-Nature
TL;DR: Scanning tunnelling microscopy is used to reveal a new topological kagome magnet with an intrinsic Chern quantum phase, which shows a distinct Landau fan structure with a large Chern gap, and the realization of a quantum-limit Chern phase in TbMn6Sn6 is point to.
Abstract: The quantum-level interplay between geometry, topology and correlation is at the forefront of fundamental physics1–15. Kagome magnets are predicted to support intrinsic Chern quantum phases owing to their unusual lattice geometry and breaking of time-reversal symmetry14,15. However, quantum materials hosting ideal spin–orbit-coupled kagome lattices with strong out-of-plane magnetization are lacking16–21. Here, using scanning tunnelling microscopy, we identify a new topological kagome magnet, TbMn6Sn6, that is close to satisfying these criteria. We visualize its effectively defect-free, purely manganese-based ferromagnetic kagome lattice with atomic resolution. Remarkably, its electronic state shows distinct Landau quantization on application of a magnetic field, and the quantized Landau fan structure features spin-polarized Dirac dispersion with a large Chern gap. We further demonstrate the bulk–boundary correspondence between the Chern gap and the topological edge state, as well as the Berry curvature field correspondence of Chern gapped Dirac fermions. Our results point to the realization of a quantum-limit Chern phase in TbMn6Sn6, and may enable the observation of topological quantum phenomena in the RMn6Sn6 (where R is a rare earth element) family with a variety of magnetic structures. Our visualization of the magnetic bulk–boundary–Berry correspondence covering real space and momentum space demonstrates a proof-of-principle method for revealing topological magnets. Scanning tunnelling microscopy is used to reveal a new topological kagome magnet with an intrinsic Chern quantum phase, which shows a distinct Landau fan structure with a large Chern gap.

253 citations


Journal ArticleDOI
TL;DR: This comprehensive systematic review and meta-analysis of group design studies of nonpharmacological early interventions designed for young children with autism spectrum disorder (ASD) found that when study quality indicators were not taken into account, significant positive effects were found for behavioral, developmental, and NDBI intervention types.
Abstract: In this comprehensive systematic review and meta-analysis of group design studies of nonpharmacological early interventions designed for young children with autism spectrum disorder (ASD), we report summary effects across 7 early intervention types (behavioral, developmental, naturalistic developmental behavioral intervention [NDBI], TEACCH, sensory-based, animal-assisted, and technology-based), and 15 outcome categories indexing core and related ASD symptoms. A total of 1,615 effect sizes were gathered from 130 independent participant samples. A total of 6,240 participants, who ranged in age from 0-8 years, are represented across the studies. We synthesized effects within intervention and outcome type using a robust variance estimation approach to account for the nesting of effect sizes within studies. We also tracked study quality indicators, and report an additional set of summary effect sizes that restrict included studies to those meeting prespecified quality indicators. Finally, we conducted moderator analyses to evaluate whether summary effects across intervention types were larger for proximal as compared with distal effects, and for context-bound as compared to generalized effects. We found that when study quality indicators were not taken into account, significant positive effects were found for behavioral, developmental, and NDBI intervention types. When effect size estimation was limited to studies with randomized controlled trial (RCT) designs, evidence of positive summary effects existed only for developmental and NDBI intervention types. This was also the case when outcomes measured by parent report were excluded. Finally, when effect estimation was limited to RCT designs and to outcomes for which there was no risk of detection bias, no intervention types showed significant effects on any outcome. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

231 citations


Journal ArticleDOI
TL;DR: A theory is developed that shows signaling a firm’s fundamental quality to lenders through inventory transactions to be more efficient—it leads to less costly ope...
Abstract: We develop a theory that shows signaling a firm’s fundamental quality (e.g., its operational capabilities) to lenders through inventory transactions to be more efficient—it leads to less costly ope...

230 citations


Journal ArticleDOI
TL;DR: In this article, an active and selective catalyst with an active interface between Au-Pd alloy nanoparticles (NPs) and cobalt oxide supports via calcination of a composite of NPs encapsulated in metal-organic frameworks (MOFs).
Abstract: The selective oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA) is an important biomass conversion reaction. However, the multiple intermediates of the reaction make the catalyst design challenging. We engineered an active and selective catalyst with an active interface between Au-Pd alloy nanoparticles (NPs) and cobalt oxide supports via calcination of a composite of NPs encapsulated in metal-organic frameworks (MOFs). The catalyst shows an effective HMF-to-FDCA oxidation with total conversion and 95 % yield by 10 % hydrogen peroxide solution at 90 °C in one hour under atmospheric pressure. The mechanistic study shows that the engineered interface promotes the formation of hydroperoxyl radicals and dioxygen molecules, which accelerate the oxidation of reactive intermediates to FDCA. This work demonstrates the advantage of using MOF composites as a precursor to generate complex but active interfaces with a strong interaction between the metal and metal oxides.

228 citations


Journal ArticleDOI
Shaohong Feng1, Josefin Stiller2, Yuan Deng2, Joel Armstrong3  +166 moreInstitutions (77)
12 Nov 2020-Nature
TL;DR: The densely sampled alignment provides a single-base-pair map of selection, has more than doubled the fraction of bases that are confidently predicted to be under conservation and reveals extensive patterns of weak selection in predominantly non-coding DNA.
Abstract: Whole-genome sequencing projects are increasingly populating the tree of life and characterizing biodiversity1-4. Sparse taxon sampling has previously been proposed to confound phylogenetic inference5, and captures only a fraction of the genomic diversity. Here we report a substantial step towards the dense representation of avian phylogenetic and molecular diversity, by analysing 363 genomes from 92.4% of bird families-including 267 newly sequenced genomes produced for phase II of the Bird 10,000 Genomes (B10K) Project. We use this comparative genome dataset in combination with a pipeline that leverages a reference-free whole-genome alignment to identify orthologous regions in greater numbers than has previously been possible and to recognize genomic novelties in particular bird lineages. The densely sampled alignment provides a single-base-pair map of selection, has more than doubled the fraction of bases that are confidently predicted to be under conservation and reveals extensive patterns of weak selection in predominantly non-coding DNA. Our results demonstrate that increasing the diversity of genomes used in comparative studies can reveal more shared and lineage-specific variation, and improve the investigation of genomic characteristics. We anticipate that this genomic resource will offer new perspectives on evolutionary processes in cross-species comparative analyses and assist in efforts to conserve species.

207 citations


Journal ArticleDOI
Thomas Lecocq1, Stephen Hicks2, Koen Van Noten1, Kasper van Wijk3, Paula Koelemeijer4, Raphael S. M. De Plaen5, Frédérick Massin6, Gregor Hillers7, Robert E. Anthony8, Maria-Theresia Apoloner9, Mario Arroyo-Solórzano10, Jelle Assink11, Pınar Büyükakpınar12, Pınar Büyükakpınar13, Andrea Cannata14, Andrea Cannata15, Flavio Cannavò15, Sebastián Carrasco16, Corentin Caudron17, Esteban J. Chaves, Dave Cornwell18, David Craig19, Olivier F. C. den Ouden11, Olivier F. C. den Ouden20, Jordi Diaz21, Stefanie Donner22, Christos Evangelidis, Läslo Evers20, Läslo Evers11, Benoit Fauville, Gonzalo A. Fernandez, Dimitrios Giannopoulos23, Steven J. Gibbons24, Társilo Girona25, Bogdan Grecu, Marc Grunberg26, György Hetényi27, Anna Horleston28, Adolfo Inza, Jessica C. E. Irving29, Jessica C. E. Irving28, Mohammadreza Jamalreyhani30, Mohammadreza Jamalreyhani13, Alan L. Kafka31, Mathijs Koymans11, Mathijs Koymans20, C. R. Labedz32, Eric Larose17, Nathaniel J. Lindsey33, Mika McKinnon34, Mika McKinnon35, T. Megies36, Meghan S. Miller37, William G. Minarik38, Louis Moresi37, Victor H. Márquez-Ramírez5, Martin Möllhoff19, Ian M. Nesbitt39, Shankho Niyogi40, Javier Ojeda41, Adrien Oth, Simon Richard Proud42, Jay J. Pulli43, Jay J. Pulli31, Lise Retailleau44, Annukka E. Rintamäki7, Claudio Satriano44, Martha K. Savage45, Shahar Shani-Kadmiel20, Reinoud Sleeman11, Efthimios Sokos46, Klaus Stammler22, Alexander E. Stott2, Shiba Subedi27, Mathilde B. Sørensen47, Taka'aki Taira48, Mar Tapia49, Fatih Turhan12, Ben A. van der Pluijm50, Mark Vanstone, Jérôme Vergne26, Tommi Vuorinen7, Tristram Warren42, Joachim Wassermann36, Han Xiao51 
Royal Observatory of Belgium1, Imperial College London2, University of Auckland3, Royal Holloway, University of London4, National Autonomous University of Mexico5, Swiss Seismological Service6, University of Helsinki7, United States Geological Survey8, Central Institution for Meteorology and Geodynamics9, University of Costa Rica10, Royal Netherlands Meteorological Institute11, Kandilli Observatory and Earthquake Research Institute12, University of Potsdam13, University of Catania14, National Institute of Geophysics and Volcanology15, University of Cologne16, University of Savoy17, King's College, Aberdeen18, Dublin Institute for Advanced Studies19, Delft University of Technology20, Spanish National Research Council21, Institute for Geosciences and Natural Resources22, Mediterranean University23, Norwegian Geotechnical Institute24, University of Alaska Fairbanks25, University of Strasbourg26, University of Lausanne27, University of Bristol28, Princeton University29, University of Tehran30, Boston College31, California Institute of Technology32, Stanford University33, Search for extraterrestrial intelligence34, University of British Columbia35, Ludwig Maximilian University of Munich36, Australian National University37, McGill University38, University of Maine39, University of California, Riverside40, University of Chile41, University of Oxford42, BBN Technologies43, Institut de Physique du Globe de Paris44, Victoria University of Wellington45, University of Patras46, University of Bergen47, University of California, Berkeley48, Institut d'Estudis Catalans49, University of Michigan50, University of California, Santa Barbara51
11 Sep 2020-Science
TL;DR: The 2020 seismic noise quiet period is the longest and most prominent global anthropogenic seismic noise reduction on record and suggests that seismology provides an absolute, real-time estimate of human activities.
Abstract: Human activity causes vibrations that propagate into the ground as high-frequency seismic waves. Measures to mitigate the coronavirus disease 2019 (COVID-19) pandemic caused widespread changes in human activity, leading to a months-long reduction in seismic noise of up to 50%. The 2020 seismic noise quiet period is the longest and most prominent global anthropogenic seismic noise reduction on record. Although the reduction is strongest at surface seismometers in populated areas, this seismic quiescence extends for many kilometers radially and hundreds of meters in depth. This quiet period provides an opportunity to detect subtle signals from subsurface seismic sources that would have been concealed in noisier times and to benchmark sources of anthropogenic noise. A strong correlation between seismic noise and independent measurements of human mobility suggests that seismology provides an absolute, real-time estimate of human activities.

202 citations


Journal ArticleDOI
TL;DR: This work examines the known and potential impacts of ocean pollution on human health, identifies gaps in knowledge, project future trends, and proposes priorities for interventions to control and prevent pollution of the seas and safeguard human health.
Abstract: Background: Pollution – unwanted waste released to air, water, and land by human activity – is the largest environmental cause of disease in the world today. It is responsible for an estimated nine million premature deaths per year, enormous economic losses, erosion of human capital, and degradation of ecosystems. Ocean pollution is an important, but insufficiently recognized and inadequately controlled component of global pollution. It poses serious threats to human health and well-being. The nature and magnitude of these impacts are only beginning to be understood. Goals: (1) Broadly examine the known and potential impacts of ocean pollution on human health. (2) Inform policy makers, government leaders, international organizations, civil society, and the global public of these threats. (3) Propose priorities for interventions to control and prevent pollution of the seas and safeguard human health. Methods: Topic-focused reviews that examine the effects of ocean pollution on human health, identify gaps in knowledge, project future trends, and offer evidence-based guidance for effective intervention. Environmental Findings: Pollution of the oceans is widespread, worsening, and in most countries poorly controlled. It is a complex mixture of toxic metals, plastics, manufactured chemicals, petroleum, urban and industrial wastes, pesticides, fertilizers, pharmaceutical chemicals, agricultural runoff, and sewage. More than 80% arises from land-based sources. It reaches the oceans through rivers, runoff, atmospheric deposition and direct discharges. It is often heaviest near the coasts and most highly concentrated along the coasts of low- and middle-income countries. Plastic is a rapidly increasing and highly visible component of ocean pollution, and an estimated 10 million metric tons of plastic waste enter the seas each year. Mercury is the metal pollutant of greatest concern in the oceans; it is released from two main sources – coal combustion and small-scale gold mining. Global spread of industrialized agriculture with increasing use of chemical fertilizer leads to extension of Harmful Algal Blooms (HABs) to previously unaffected regions. Chemical pollutants are ubiquitous and contaminate seas and marine organisms from the high Arctic to the abyssal depths. Ecosystem Findings: Ocean pollution has multiple negative impacts on marine ecosystems, and these impacts are exacerbated by global climate change. Petroleum-based pollutants reduce photosynthesis in marine microorganisms that generate oxygen. Increasing absorption of carbon dioxide into the seas causes ocean acidification, which destroys coral reefs, impairs shellfish development, dissolves calcium-containing microorganisms at the base of the marine food web, and increases the toxicity of some pollutants. Plastic pollution threatens marine mammals, fish, and seabirds and accumulates in large mid-ocean gyres. It breaks down into microplastic and nanoplastic particles containing multiple manufactured chemicals that can enter the tissues of marine organisms, including species consumed by humans. Industrial releases, runoff, and sewage increase frequency and severity of HABs, bacterial pollution, and anti-microbial resistance. Pollution and sea surface warming are triggering poleward migration of dangerous pathogens such as the Vibrio species. Industrial discharges, pharmaceutical wastes, pesticides, and sewage contribute to global declines in fish stocks. Human Health Findings: Methylmercury and PCBs are the ocean pollutants whose human health effects are best understood. Exposures of infants in utero to these pollutants through maternal consumption of contaminated seafood can damage developing brains, reduce IQ and increase children’s risks for autism, ADHD and learning disorders. Adult exposures to methylmercury increase risks for cardiovascular disease and dementia. Manufactured chemicals – phthalates, bisphenol A, flame retardants, and perfluorinated chemicals, many of them released into the seas from plastic waste – can disrupt endocrine signaling, reduce male fertility, damage the nervous system, and increase risk of cancer. HABs produce potent toxins that accumulate in fish and shellfish. When ingested, these toxins can cause severe neurological impairment and rapid death. HAB toxins can also become airborne and cause respiratory disease. Pathogenic marine bacteria cause gastrointestinal diseases and deep wound infections. With climate change and increasing pollution, risk is high that Vibrio infections, including cholera, will increase in frequency and extend to new areas. All of the health impacts of ocean pollution fall disproportionately on vulnerable populations in the Global South – environmental injustice on a planetary scale. Conclusions: Ocean pollution is a global problem. It arises from multiple sources and crosses national boundaries. It is the consequence of reckless, shortsighted, and unsustainable exploitation of the earth’s resources. It endangers marine ecosystems. It impedes the production of atmospheric oxygen. Its threats to human health are great and growing, but still incompletely understood. Its economic costs are only beginning to be counted. Ocean pollution can be prevented. Like all forms of pollution, ocean pollution can be controlled by deploying data-driven strategies based on law, policy, technology, and enforcement that target priority pollution sources. Many countries have used these tools to control air and water pollution and are now applying them to ocean pollution. Successes achieved to date demonstrate that broader control is feasible. Heavily polluted harbors have been cleaned, estuaries rejuvenated, and coral reefs restored. Prevention of ocean pollution creates many benefits. It boosts economies, increases tourism, helps restore fisheries, and improves human health and well-being. It advances the Sustainable Development Goals (SDG). These benefits will last for centuries. Recommendations: World leaders who recognize the gravity of ocean pollution, acknowledge its growing dangers, engage civil society and the global public, and take bold, evidence-based action to stop pollution at source will be critical to preventing ocean pollution and safeguarding human health. Prevention of pollution from land-based sources is key. Eliminating coal combustion and banning all uses of mercury will reduce mercury pollution. Bans on single-use plastic and better management of plastic waste reduce plastic pollution. Bans on persistent organic pollutants (POPs) have reduced pollution by PCBs and DDT. Control of industrial discharges, treatment of sewage, and reduced applications of fertilizers have mitigated coastal pollution and are reducing frequency of HABs. National, regional and international marine pollution control programs that are adequately funded and backed by strong enforcement have been shown to be effective. Robust monitoring is essential to track progress. Further interventions that hold great promise include wide-scale transition to renewable fuels; transition to a circular economy that creates little waste and focuses on equity rather than on endless growth; embracing the principles of green chemistry; and building scientific capacity in all countries. Designation of Marine Protected Areas (MPAs) will safeguard critical ecosystems, protect vulnerable fish stocks, and enhance human health and well-being. Creation of MPAs is an important manifestation of national and international commitment to protecting the health of the seas.

Journal ArticleDOI
TL;DR: In response to initial voices that put the customer experience (management) (CX(M)) movement into question, this article introduced a formal nomenclature to push the CX (M) field toward a mor...
Abstract: In response to initial voices that put the customer experience (management) (CX(M)) movement into question, this article aims to introduce a formal nomenclature to push the CX(M) field toward a mor...

Posted ContentDOI
30 Mar 2020-medRxiv
TL;DR: One of the first nationally representative surveys about this unprecedented public health crisis in Italy is implemented to evaluate the Italian government's public health efforts and citizen responses and concludes that the Italian people understand how to keep themselves and others safe from the SARS-Cov-2 virus.
Abstract: Purpose The COVID-19 death-rate in Italy continues to climb, surpassing that in every other country. We implement one of the first nationally representative surveys about this unprecedented public health crisis and use it to evaluate the Italian government’ public health efforts and citizen responses. Findings (1) Public health messaging is being heard. Except for slightly lower compliance among young adults, all subgroups we studied understand how to keep themselves and others safe from the SARS-Cov-2 virus. Remarkably, even those who do not trust the government, or think the government has been untruthful about the crisis believe the messaging and claim to be acting in accordance. (2) The quarantine is beginning to have serious negative effects on the population’s mental health. Policy Recommendations Communications should move from explaining to citizens that they should stay at home to what they can do there. We need interventions that make staying following public health protocols more desirable, such as virtual social interactions, online social reading activities, classes, exercise routines, etc. — all designed to reduce the boredom of long term social isolation and to increase the attractiveness of following public health recommendations. Interventions like these will grow in importance as the crisis wears on around the world, and staying inside wears on people.

Journal ArticleDOI
TL;DR: The recent applications of TIS to answer overarching biological questions are discussed and emerging and multidisciplinary methods that build on TIS are explored, with an eye towards future applications.
Abstract: It has been 10 years since the introduction of modern transposon-insertion sequencing (TIS) methods, which combine genome-wide transposon mutagenesis with high-throughput sequencing to estimate the fitness contribution or essentiality of each genetic component in a bacterial genome. Four TIS variations were published in 2009: transposon sequencing (Tn-Seq), transposon-directed insertion site sequencing (TraDIS), insertion sequencing (INSeq) and high-throughput insertion tracking by deep sequencing (HITS). TIS has since become an important tool for molecular microbiologists, being one of the few genome-wide techniques that directly links phenotype to genotype and ultimately can assign gene function. In this Review, we discuss the recent applications of TIS to answer overarching biological questions. We explore emerging and multidisciplinary methods that build on TIS, with an eye towards future applications.

Journal ArticleDOI
31 Jan 2020-Science
TL;DR: Isotopically pure cubic boron nitride has an ultrahigh thermal conductivity, 75% that of diamond, which makes cBN a promising material for microelectronics thermal management, high-power electronics, and optoelectronics applications.
Abstract: Materials with high thermal conductivity (κ) are of technological importance and fundamental interest. We grew cubic boron nitride (cBN) crystals with controlled abundance of boron isotopes and measured κ greater than 1600 watts per meter-kelvin at room temperature in samples with enriched 10B or 11B. In comparison, we found that the isotope enhancement of κ is considerably lower for boron phosphide and boron arsenide as the identical isotopic mass disorder becomes increasingly invisible to phonons. The ultrahigh κ in conjunction with its wide bandgap (6.2 electron volts) makes cBN a promising material for microelectronics thermal management, high-power electronics, and optoelectronics applications.

Journal ArticleDOI
TL;DR: The replication crisis in experimental social psychology has led to new standards for transparency in management journals as mentioned in this paper, leading to a new set of standards for accountability and transparency in the publishing of data.
Abstract: Management journals are currently responding to challenges raised by the “replication crisis” in experimental social psychology, leading to new standards for transparency. These approaches are spil...

Journal ArticleDOI
03 Dec 2020-Nature
TL;DR: Electronic ferroelectricity is observed in a graphene-based moiré heterostructure, which is explained using a spontaneous interlayer charge-transfer model driven by layer-specific on-site Coulomb repulsion.
Abstract: The constituent particles of matter can arrange themselves in various ways, giving rise to emergent phenomena that can be surprisingly rich and often cannot be understood by studying only the individual constituents. Discovering and understanding the emergence of such phenomena in quantum materials-especially those in which multiple degrees of freedom or energy scales are delicately balanced-is of fundamental interest to condensed-matter research1,2. Here we report on the surprising observation of emergent ferroelectricity in graphene-based moire heterostructures. Ferroelectric materials show electrically switchable electric dipoles, which are usually formed by spatial separation between the average centres of positive and negative charge within the unit cell. On this basis, it is difficult to imagine graphene-a material composed of only carbon atoms-exhibiting ferroelectricity3. However, in this work we realize switchable ferroelectricity in Bernal-stacked bilayer graphene sandwiched between two hexagonal boron nitride layers. By introducing a moire superlattice potential (via aligning bilayer graphene with the top and/or bottom boron nitride crystals), we observe prominent and robust hysteretic behaviour of the graphene resistance with an externally applied out-of-plane displacement field. Our systematic transport measurements reveal a rich and striking response as a function of displacement field and electron filling, and beyond the framework of conventional ferroelectrics. We further directly probe the ferroelectric polarization through a non-local monolayer graphene sensor. Our results suggest an unconventional, odd-parity electronic ordering in the bilayer graphene/boron nitride moire system. This emergent moire ferroelectricity may enable ultrafast, programmable and atomically thin carbon-based memory devices.

Journal ArticleDOI
TL;DR: In this paper, a hierarchical Fe3-xC@C hollow microspheres as an advanced sulfur immobilizer and promoter for enabling high-efficiency Li-S batteries is developed, which not only accommodates the volume variation upon the lithiation-delithiation processes, but exposes vast active interfaces for facilitated sulfur redox reactions.
Abstract: Lithium–sulfur (Li–S) batteries present one of the most promising energy storage systems owing to their high energy density and low cost. However, the commercialization of Li–S batteries is still hindered by several technical issues; the notorious polysulfide shuttling and sluggish sulfur conversion kinetics. In this work, unique hierarchical Fe3-xC@C hollow microspheres as an advanced sulfur immobilizer and promoter for enabling high-efficiency Li–S batteries is developed. The porous hollow architecture not only accommodates the volume variation upon the lithiation–delithiation processes, but also exposes vast active interfaces for facilitated sulfur redox reactions. Meanwhile, the mesoporous carbon coating establishes a highly conductive network for fast electron transportation. More importantly, the defective Fe3-xC nanosized subunits impose strong LiPS adsorption and catalyzation, enabling fast and durable sulfur electrochemistry. Attributed to these structural superiorities, the obtained sulfur electrodes exhibit excellent electrochemical performance, i.e., high areal capacity of 5.6 mAh cm-2, rate capability up to 5 C, and stable cycling over 1000 cycles with a low capacity fading rate of 0.04% per cycle at 1 C, demonstrating great promise in the development of practical Li–S batteries.

Journal ArticleDOI
TL;DR: It is found that the extent to which workers are dependent on platform income to pay basic expenses rather than working for supplemental income explains the variation in outcomes, which suggests platforms are free-riding on conventional employers.
Abstract: The rapid growth of Uber and analogous platform companies has led to considerable scholarly interest in the phenomenon of platform labor. Scholars have taken two main approaches to explaining outcomes for platform work-precarity, which focuses on employment classification and insecure labor, and technological control via algorithms. Both predict that workers will have relatively common experiences. On the basis of 112 in-depth interviews with workers on seven platforms (Airbnb, TaskRabbit, Turo, Uber, Lyft, Postmates, and Favor) we find heterogeneity of experiences across and within platforms. We argue that because platform labor is weakly institutionalized, worker satisfaction, autonomy, and earnings vary significantly across and within platforms, suggesting dominant interpretations are insufficient. We find that the extent to which workers are dependent on platform income to pay basic expenses rather than working for supplemental income explains the variation in outcomes, with supplemental earners being more satisfied and higher-earning. This suggests platforms are free-riding on conventional employers. We also find that platforms are hierarchically ordered, in terms of what providers can earn, conditions of work, and their ability to produce satisfied workers. Our findings suggest the need for a new analytic approach to platforms, which emphasizes labor force diversity, connections to conventional labor markets, and worker dependence.

Journal ArticleDOI
TL;DR: Evidence of key functional interactions among PM regions and their relation to the core cognitive operations and representations supporting episodic construction are reviewed to inform a network-based model of episodicConstruction.

Journal ArticleDOI
TL;DR: In this article, the Coulomb interaction was used to study the ground states of twisted bilayer graphene with a Hartree-Fock approximation, and the results provided good reference points for further study of the rich correlated physics in the twisted bilayers graphene.
Abstract: Motivated by the recently observed insulating states in twisted bilayer graphene, we study the nature of the correlated insulating phases of the twisted bilayer graphene at commensurate filling fractions. We use the continuum model and project the Coulomb interaction onto the flat bands to study the ground states by using a Hartree-Fock approximation. In the absence of the hexagonal boron nitride substrate, the ground states are the intervalley coherence states at charge neutrality (filling $\ensuremath{ u}=0$, or four electrons per moir\'e cell) and at $\ensuremath{ u}=\ensuremath{-}1/4$ and $\ensuremath{-}1/2$ (three and two electrons per cell, respectively) and the ${C}_{2}\mathcal{T}$ symmetry-broken state at $\ensuremath{ u}=\ensuremath{-}3/4$ (one electron per cell). The hexagonal boron nitride substrate drives the ground states at all $\ensuremath{ u}$ into ${C}_{2}\mathcal{T}$ symmetry broken-states. Our results provide good reference points for further study of the rich correlated physics in the twisted bilayer graphene.

Journal ArticleDOI
26 Mar 2020-Nature
TL;DR: Scanning tunnelling microscopy and spectroscopy measurements show chiral edge states inside the superconducting gap of the recently discovered heavy-fermion superconductor UTe2, indicating the presence of chiral spin-triplet superconductivity.
Abstract: Spin-triplet superconductors are condensates of electron pairs with spin 1 and an odd-parity wavefunction1. An interesting manifestation of triplet pairing is the chiral p-wave state, which is topologically non-trivial and provides a natural platform for realizing Majorana edge modes2,3. However, triplet pairing is rare in solid-state systems and has not been unambiguously identified in any bulk compound so far. Given that pairing is usually mediated by ferromagnetic spin fluctuations, uranium-based heavy-fermion systems containing f-electron elements, which can harbour both strong correlations and magnetism, are considered ideal candidates for realizing spin-triplet superconductivity4. Here we present scanning tunnelling microscopy studies of the recently discovered heavy-fermion superconductor UTe2, which has a superconducting transition temperature of 1.6 kelvin5. We find signatures of coexisting Kondo effect and superconductivity that show competing spatial modulations within one unit cell. Scanning tunnelling spectroscopy at step edges reveals signatures of chiral in-gap states, which have been predicted to exist at the boundaries of topological superconductors. Combined with existing data that indicate triplet pairing in UTe2, the presence of chiral states suggests that UTe2 is a strong candidate for chiral-triplet topological superconductivity.

Journal ArticleDOI
TL;DR: In this article, the effects of Instagram influencers and their branded-UGC on consumer behavior outcomes were investigated. But the authors focused on the dynamics of interaction among brand-related user-generated contents (UGC) posted on Instagram, social media-based brand communication with Instagram celebrities (parasocial interaction [PSI] and envy), and consumers' characteristics (social comparison tendency, compulsive buying tendency, and materialistic envy).

Journal ArticleDOI
Michael C. Frank1, Katherine J. Alcock2, Natalia Arias-Trejo3, Gisa Aschersleben4, Dare A. Baldwin5, Stéphanie Barbu, Elika Bergelson6, Christina Bergmann7, Alexis K. Black8, Ryan Blything9, Maximilian P. Böhland10, Petra Bolitho11, Arielle Borovsky12, Shannon M. Brady13, Bettina Braun14, Anna Brown15, Krista Byers-Heinlein16, Linda E. Campbell17, Cara H. Cashon18, Mihye Choi19, Joan Christodoulou13, Laura K. Cirelli20, Stefania Conte21, Sara Cordes22, Christopher Martin Mikkelsen Cox23, Alejandrina Cristia, Rhodri Cusack24, Catherine Davies25, Maartje de Klerk26, Claire Delle Luche27, Laura E. de Ruiter28, Dhanya Dinakar29, Kate C. Dixon18, Virginie Durier, S. Durrant15, Christopher T. Fennell30, Brock Ferguson, Alissa L. Ferry28, Paula Fikkert31, Teresa Flanagan32, Caroline Floccia33, Megan Foley34, Tom Fritzsche35, Rebecca Louise Ann Frost7, Anja Gampe36, Judit Gervain, Nayeli Gonzalez-Gomez37, Anna Gupta38, Laura E. Hahn31, J. Kiley Hamlin39, Erin E. Hannon40, Naomi Havron, Jessica F. Hay41, Mikołaj Hernik42, Barbara Höhle35, Derek M. Houston43, Lauren H. Howard32, Mitsuhiko Ishikawa44, Shoji Itakura44, Iain Jackson28, Krisztina V. Jakobsen45, Marianna Jartó46, Scott P. Johnson13, Caroline Junge26, Didar Karadag47, Natalia Kartushina48, Danielle J. Kellier1, Tamar Keren-Portnoy23, Kelsey Klassen49, Melissa Kline50, Eon-Suk Ko51, Jonathan F. Kominsky52, Jessica E. Kosie5, Haley E. Kragness53, Andrea A. R. Krieger4, Florian Krieger54, Jill Lany55, Roberto J. Lazo56, Michelle Lee57, Chloé Leservoisier, Claartje Levelt38, Casey Lew-Williams58, Matthias Lippold59, Ulf Liszkowski46, Liquan Liu29, Steven G. Luke60, Rebecca A. Lundwall60, Viola Macchi Cassia21, Nivedita Mani59, Caterina Marino, Alia Martin11, Meghan Mastroberardino16, Victoria Mateu13, Julien Mayor48, Katharina Menn31, Christine Michel7, Yusuke Moriguchi44, Benjamin Morris61, Karli M. Nave40, Thierry Nazzi, Claire Noble15, Miriam A. Novack62, Nonah M. Olesen18, Adriel John Orena63, Mitsuhiko Ota64, Robin Panneton65, Sara Parvanezadeh Esfahani41, Markus Paulus66, Carolina Pletti66, Linda Polka63, Christine E. Potter58, Hugh Rabagliati64, Shruthilaya Ramachandran67, Jennifer L. Rennels40, Greg D. Reynolds41, Kelly C. Roth41, Charlotte Rothwell2, Doroteja Rubez43, Yana Ryjova40, Jenny R. Saffran68, Ayumi Sato69, Sophie Savelkouls22, Adena Schachner57, Graham Schafer70, Melanie S. Schreiner59, Amanda Seidl12, Mohinish Shukla19, Elizabeth A. Simpson56, Leher Singh67, Barbora Skarabela64, Gaye Soley47, Megha Sundara13, Anna L. Theakston28, Abbie Thompson55, Laurel J. Trainor53, Sandra E. Trehub20, Anna S. Trøan48, Angeline Sin-Mei Tsui30, Katherine Elizabeth Twomey28, Katie Von Holzen, Yuanyuan Wang43, Sandra R. Waxman62, Janet F. Werker39, Stephanie Wermelinger36, Alix Woolard17, Daniel Yurovsky61, Katharina Zahner14, Martin Zettersten68, Melanie Soderstrom49 
Stanford University1, Lancaster University2, National Autonomous University of Mexico3, Saarland University4, University of Oregon5, Duke University6, Max Planck Society7, Haskins Laboratories8, University of Bristol9, Dresden University of Technology10, Victoria University of Wellington11, Purdue University12, University of California, Los Angeles13, University of Konstanz14, University of Liverpool15, Concordia University16, University of Newcastle17, University of Louisville18, University of Massachusetts Boston19, University of Toronto20, University of Milan21, Boston College22, University of York23, Trinity College, Dublin24, University of Leeds25, Utrecht University26, University of Essex27, University of Manchester28, University of Sydney29, University of Ottawa30, Radboud University Nijmegen31, Franklin & Marshall College32, University of Plymouth33, Florida State University-Panama34, University of Potsdam35, University of Zurich36, Oxford Brookes University37, Leiden University38, University of British Columbia39, University of Nevada, Las Vegas40, University of Tennessee41, Central European University42, Ohio State University43, Kyoto University44, James Madison University45, University of Hamburg46, Boğaziçi University47, University of Oslo48, University of Manitoba49, Massachusetts Institute of Technology50, Chosun University51, Harvard University52, McMaster University53, University of Luxembourg54, University of Notre Dame55, University of Miami56, University of California, San Diego57, Princeton University58, University of Göttingen59, Brigham Young University60, University of Chicago61, Northwestern University62, McGill University63, University of Edinburgh64, Virginia Tech65, Ludwig Maximilian University of Munich66, National University of Singapore67, University of Wisconsin-Madison68, Shimane University69, University of Reading70
16 Mar 2020
TL;DR: In this paper, a large-scale, multisite study aimed at assessing the overall replicability of a single theoretically important phenomenon and examining methodological, cultural, and developmental moderators was conducted.
Abstract: Psychological scientists have become increasingly concerned with issues related to methodology and replicability, and infancy researchers in particular face specific challenges related to replicability: For example, high-powered studies are difficult to conduct, testing conditions vary across labs, and different labs have access to different infant populations. Addressing these concerns, we report on a large-scale, multisite study aimed at (a) assessing the overall replicability of a single theoretically important phenomenon and (b) examining methodological, cultural, and developmental moderators. We focus on infants’ preference for infant-directed speech (IDS) over adult-directed speech (ADS). Stimuli of mothers speaking to their infants and to an adult in North American English were created using seminaturalistic laboratory-based audio recordings. Infants’ relative preference for IDS and ADS was assessed across 67 laboratories in North America, Europe, Australia, and Asia using the three common methods for measuring infants’ discrimination (head-turn preference, central fixation, and eye tracking). The overall meta-analytic effect size (Cohen’s d) was 0.35, 95% confidence interval = [0.29, 0.42], which was reliably above zero but smaller than the meta-analytic mean computed from previous literature (0.67). The IDS preference was significantly stronger in older children, in those children for whom the stimuli matched their native language and dialect, and in data from labs using the head-turn preference procedure. Together, these findings replicate the IDS preference but suggest that its magnitude is modulated by development, native-language experience, and testing procedure.

ReportDOI
TL;DR: In the case of the COVID-19 crisis, banks drew funds on a massive scale from pre-existing credit lines and loan commitments in anticipation of cash flow disruptions.
Abstract: In March of 2020, banks faced the largest increase in liquidity demands ever observed. Firms drew funds on a massive scale from pre-existing credit lines and loan commitments in anticipation of cash flow disruptions from the economic shutdown designed to contain the COVID-19 crisis. The increase in liquidity demands was concentrated at the largest banks, who serve the largest firms. Pre-crisis financial condition did not limit banks’ liquidity supply. Coincident inflows of funds to banks from both the Federal Reserve’s liquidity injection programs and from depositors, along with strong pre-shock bank capital, explain why banks were able to accommodate these liquidity demands.

Journal ArticleDOI
TL;DR: A preliminary study on an architecture that implements blockchain in managing heterogeneous IoT systems and the difficulties of integrating IoT and blockchain is presented to stimulate further effort and cross-disciplinary collaboration.
Abstract: IoT has the potential to transform the way we think about information and communication technology. IoT has been studied extensively across many disciplines such as the networking, communication, security, business, and management communities. However, many unsolved challenges, especially in managing heterogeneous IoTs, remain to be discussed. Recent studies propose using blockchain, an emerging technology that enables decentralized coordination, to address inherent challenges in IoT. This article presents a preliminary study on an architecture that implements blockchain in managing heterogeneous IoT systems. We start by pointing out the limitations of prior IoT systems and the difficulties of integrating IoT and blockchain. Then we outline an architecture to manage a large-scale heterogeneous IoT system. Our main goal is to stimulate further effort and cross-disciplinary collaboration by providing guidance and reference for future studies.

Journal ArticleDOI
06 Jul 2020
TL;DR: In this paper, the authors explore random quantum circuit models for non-unitary quantum dynamics of free fermions in one spatial dimension and show that this model is critical and has space-time conformal symmetry.
Abstract: This work explores random quantum circuit models for non-unitary quantum dynamics of free fermions in one spatial dimension and show that this model is critical and has space-time conformal symmetry.

Journal ArticleDOI
TL;DR: National efforts to enhance advance care planning may help dying patients to receive care that is concordant with the preferences of them and their families.
Abstract: COVID-19 fatalities exemplify "bad deaths" and are distinguished by physical discomfort, difficulty breathing, social isolation, psychological distress, and care that may be discordant with the patient's preferences. Each of these death attributes is a well-documented correlate of bereaved survivors' symptoms of depression, anxiety, and anger. Yet the grief experienced by survivors of COVID-related deaths is compounded by the erosion of coping resources like social support, contemporaneous stressors including social isolation, financial precarity, uncertainty about the future, lack of routine, and the loss of face-to-face mourning rituals that provide a sense of community and uplift. National efforts to enhance advance care planning may help dying patients to receive care that is concordant with the preferences of them and their families. Virtual funeral services, pairing bereaved elders with a telephone companion, remote counseling, and encouraging "continuing bonds" may help older adults adapt to loss in the time of pandemic.

Journal ArticleDOI
TL;DR: In this paper, the authors examine why start-ups, generally characterized as flexible, malleable entities, might instead exhibit "flexibility" and "adaptability" in the air taxi market.
Abstract: Through an inductive, comparative study of four early entrants in the nascent air taxi market, we examine why start-ups, generally characterized as flexible, malleable entities, might instead exhib...

Journal ArticleDOI
TL;DR: The observation of a flat band and Dirac bands as ideal features of kagome bands in CoSn, revealing orbital-selective character of the Dirac fermions.
Abstract: Layered kagome-lattice 3d transition metals are emerging as an exciting platform to explore the frustrated lattice geometry and quantum topology. However, the typical kagome electronic bands, characterized by sets of the Dirac-like band capped by a phase-destructive flat band, have not been clearly observed, and their orbital physics are even less well investigated. Here, we present close-to-textbook kagome bands with orbital differentiation physics in CoSn, which can be well described by a minimal tight-binding model with single-orbital hopping in Co kagome lattice. The capping flat bands with bandwidth less than 0.2 eV run through the whole Brillouin zone, especially the bandwidth of the flat band of out-of-plane orbitals is less than 0.02 eV along Γ−M. The energy gap induced by spin-orbit interaction at the Dirac cone of out-of-plane orbitals is much smaller than that of in-plane orbitals, suggesting orbital-selective character of the Dirac fermions. The understanding of kagome bands, which are characterized by Dirac-like bands capped by a flat band, remains largely elusive. Here, Liu et al. report the observation of a flat band and Dirac bands as ideal features of kagome bands in CoSn, revealing orbital-selective character.