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1.
  • 2021
  • swepub:Mat__t
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2.
  • 2021
  • swepub:Mat__t
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3.
  • Bravo, L, et al. (author)
  • 2021
  • swepub:Mat__t
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4.
  • Tabiri, S, et al. (author)
  • 2021
  • swepub:Mat__t
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5.
  • Glasbey, JC, et al. (author)
  • 2021
  • swepub:Mat__t
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6.
  • Nakamura, K., et al. (author)
  • Review Of Particle Physics
  • 2010
  • In: Journal of Physics G: Nuclear and Particle Physics. - 0954-3899 .- 1361-6471. ; 37:7A, s. 1-1422
  • Research review (peer-reviewed)abstract
    • This biennial Review summarizes much of particle physics. Using data from previous editions, plus 2158 new measurements from 551 papers, we list, evaluate, and average measured properties of gauge bosons, leptons, quarks, mesons, and baryons. We also summarize searches for hypothetical particles such as Higgs bosons, heavy neutrinos, and supersymmetric particles. All the particle properties and search limits are listed in Summary Tables. We also give numerous tables, figures, formulae, and reviews of topics such as the Standard Model, particle detectors, probability, and statistics. Among the 108 reviews are many that are new or heavily revised including those on neutrino mass, mixing, and oscillations, QCD, top quark, CKM quark-mixing matrix, V-ud & V-us, V-cb & V-ub, fragmentation functions, particle detectors for accelerator and non-accelerator physics, magnetic monopoles, cosmological parameters, and big bang cosmology. A booklet is available containing the Summary Tables and abbreviated versions of some of the other sections of this full Review. All tables, listings, and reviews (and errata) are also available on the Particle Data Group website: http://pdg.1b1.gov.
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7.
  • Yao, W-M, et al. (author)
  • Review of Particle Physics
  • 2006
  • In: Journal of Physics G: Nuclear and Particle Physics. - : IOP Publishing. - 0954-3899 .- 1361-6471. ; 33:1, s. 1-1
  • Journal article (peer-reviewed)
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8.
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9.
  • Jin, S. C., et al. (author)
  • Mutations disrupting neuritogenesis genes confer risk for cerebral palsy
  • 2020
  • In: Nature Genetics. - : Springer Science and Business Media LLC. - 1061-4036 .- 1546-1718. ; 52:10
  • Journal article (peer-reviewed)abstract
    • Whole-exome sequencing of 250 parent-offspring trios identifies an enrichment of rare damaging de novo mutations in individuals with cerebral palsy and implicates genetically mediated dysregulation of early neuronal connectivity in the etiology of this disorder. In addition to commonly associated environmental factors, genomic factors may cause cerebral palsy. We performed whole-exome sequencing of 250 parent-offspring trios, and observed enrichment of damaging de novo mutations in cerebral palsy cases. Eight genes had multiple damaging de novo mutations; of these, two (TUBA1AandCTNNB1) met genome-wide significance. We identified two novel monogenic etiologies,FBXO31andRHOB, and showed that theRHOBmutation enhances active-state Rho effector binding while theFBXO31mutation diminishes cyclin D levels. Candidate cerebral palsy risk genes overlapped with neurodevelopmental disorder genes. Network analyses identified enrichment of Rho GTPase, extracellular matrix, focal adhesion and cytoskeleton pathways. Cerebral palsy risk genes in enriched pathways were shown to regulate neuromotor function in aDrosophilareverse genetics screen. We estimate that 14% of cases could be attributed to an excess of damaging de novo or recessive variants. These findings provide evidence for genetically mediated dysregulation of early neuronal connectivity in cerebral palsy.
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10.
  • Webber, K. B., et al. (author)
  • Chemical Analysis of the Brightest Star of the Cetus II Ultrafaint Dwarf Galaxy Candidate
  • 2023
  • In: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 959:2
  • Journal article (peer-reviewed)abstract
    • We present a detailed chemical abundance analysis of the brightest star in the ultrafaint dwarf (UFD) galaxy candidate Cetus II from high-resolution Magellan/MIKE spectra. For this star, DES J011740.53-173053, abundances or upper limits of 18 elements from carbon to europium are derived. Its chemical abundances generally follow those of other UFD galaxy stars, with a slight enhancement of the alpha-elements (Mg, Si, and Ca) and low neutron-capture element (Sr, Ba, and Eu) abundances supporting the classification of Cetus II as a likely UFD. The star exhibits lower Sc, Ti, and V abundances than Milky Way (MW) halo stars with similar metallicity. This signature is consistent with yields from a supernova originating from a star with a mass of similar to 11.2 M-circle dot. In addition, the star has a potassium abundance of [K/Fe] = 0.81, which is somewhat higher than the K abundances of MW halo stars with similar metallicity, a signature that is also present in a number of UFD galaxies. A comparison including globular clusters and stellar stream stars suggests that high K is a specific characteristic of some UFD galaxy stars and can thus be used to help classify objects as UFD galaxies.
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11.
  • Hagiwara, K, et al. (author)
  • Review of particle physics
  • 2002
  • In: Physical Review D (Particles and Fields). - 0556-2821. ; 66:1
  • Research review (peer-reviewed)abstract
    • This biennial Review summarizes much of Particle Physics Using data from previous editions, plus 2205 new measurements from 667 papers, we list, evaluate, and average measured properties of gauge bosons, leptons, quarks, mesons, and baryons We also summarize searches for hypothetical particles such as Higgs bosons, heavy neutrinos, and supersymmetric particles All the particle properties and search limits are listed in Summary Tables We also give numerous tables, figures, formulae, and reviews of topics such as the Standard Model, particle detectors, probability, and statistics This edition features expanded coverage of CP violation in B mesons and of neutrino oscillations For the first time we cover searches for evidence of extra dimensions (both in the particle listings and in a new review) Another new review is on Grand Unified Theories A booklet is available containing the Summary Tables and abbreviated versions of some of the other sections of this full Review All tables, listings, and reviews (and errata) are also available on the Particle Data Group website http //pdg 1b1 gov.
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12.
  • Alexander-Webber, J. A., et al. (author)
  • Phase Space for the Breakdown of the Quantum Hall Effect in Epitaxial Graphene
  • 2013
  • In: Physical Review Letters. - : American Physical Society. - 0031-9007 .- 1079-7114. ; 111:9, s. e096601-
  • Journal article (peer-reviewed)abstract
    • We report the phase space defined by the quantum Hall effect breakdown in polymer gated epitaxial graphene on SiC (SiC/G) as a function of temperature, current, carrier density, and magnetic fields up to 30 T. At 2 K, breakdown currents (Ic) almost 2 orders of magnitude greater than in GaAs devices are observed. The phase boundary of the dissipationless state (ρxx=0) shows a [1-(T/Tc)2] dependence and persists up to Tc>45  K at 29 T. With magnetic field Ic was found to increase ∝B3/2 and Tc∝B2. As the Fermi energy approaches the Dirac point, the ν=2 quantized Hall plateau appears continuously from fields as low as 1 T up to at least 19 T due to a strong magnetic field dependence of the carrier density.
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13.
  • Alwall, J., et al. (author)
  • A standard format for Les Houches Event Files
  • 2007
  • In: Computer Physics Communications. - : Elsevier BV. - 0010-4655. ; 176:4, s. 300-304
  • Journal article (peer-reviewed)abstract
    • A standard file format is proposed to store process and event information, primarily output from partoti-level event generators for further use by general-purpose ones. The information content is identical with what was already defined by the Les Houches Accord five years ago, but then in terms of Fortran commonblocks. This information is embedded in a minimal XML-style structure, for clarity and to simplify parsing.
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14.
  • Giele, Walter, et al. (author)
  • The QCD / SM working group: Summary report
  • 2002
  • In: Physics at TeV colliders. Proceedings, Euro Summer School, Les Houches, France, May 21-June 1, 2001. ; , s. 275-426, s. 275-426
  • Conference paper (other academic/artistic)
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15.
  • Grenn, Francis P., et al. (author)
  • The Parkinson's Disease Genome-Wide Association Study Locus Browser
  • 2020
  • In: Movement Disorders. - : Wiley. - 0885-3185 .- 1531-8257.
  • Journal article (peer-reviewed)abstract
    • Background: Parkinson's disease (PD) is a neurodegenerative disease with an often complex component identifiable by genome-wide association studies. The most recent large-scale PD genome-wide association studies have identified more than 90 independent risk variants for PD risk and progression across more than 80 genomic regions. One major challenge in current genomics is the identification of the causal gene(s) and variant(s) at each genome-wide association study locus. The objective of the current study was to create a tool that would display data for relevant PD risk loci and provide guidance with the prioritization of causal genes and potential mechanisms at each locus. Methods: We included all significant genome-wide signals from multiple recent PD genome-wide association studies including themost recent PD risk genome-wide association study, age-at-onset genome-wide association study, progression genome-wide association study, and Asian population PD risk genome-wide association study. We gathered data for all genes 1 Mb up and downstream of each variant to allow users to assess which gene(s) are most associated with the variant of interest based on a set of self-ranked criteria. Multiple databases were queried for each gene to collect additional causal data. Results: We created a PD genome-wide association study browser tool (https://pdgenetics.shinyapps.io/GWASBrowser/) to assist the PD research community with the prioritization of genes for follow-up functional studies to identify potential therapeutic targets. Conclusions: Our PD genome-wide association study browser tool provides users with a useful method of identifying potential causal genes at all known PD risk loci from large-scale PD genome-wide association studies. We plan to update this tool with new relevant data as sample sizes increase and new PD risk loci are discovered.
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16.
  • Hillier, Ladeana W, et al. (author)
  • Sequence and comparative analysis of the chicken genome provide unique perspectives on vertebrate evolution
  • 2004
  • In: Nature. - 0028-0836 .- 1476-4687. ; 432:7018, s. 695-716
  • Journal article (peer-reviewed)abstract
    • We present here a draft genome sequence of the red jungle fowl, Gallus gallus. Because the chicken is a modern descendant of the dinosaurs and the first non-mammalian amniote to have its genome sequenced, the draft sequence of its genome--composed of approximately one billion base pairs of sequence and an estimated 20,000-23,000 genes--provides a new perspective on vertebrate genome evolution, while also improving the annotation of mammalian genomes. For example, the evolutionary distance between chicken and human provides high specificity in detecting functional elements, both non-coding and coding. Notably, many conserved non-coding sequences are far from genes and cannot be assigned to defined functional classes. In coding regions the evolutionary dynamics of protein domains and orthologous groups illustrate processes that distinguish the lineages leading to birds and mammals. The distinctive properties of avian microchromosomes, together with the inferred patterns of conserved synteny, provide additional insights into vertebrate chromosome architecture.
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17.
  • Lindblad-Toh, Kerstin, et al. (author)
  • Genome sequence, comparative analysis and haplotype structure of the domestic dog.
  • 2005
  • In: Nature. - : Springer Science and Business Media LLC. - 1476-4687 .- 0028-0836. ; 438:7069, s. 803-19
  • Journal article (peer-reviewed)abstract
    • Here we report a high-quality draft genome sequence of the domestic dog (Canis familiaris), together with a dense map of single nucleotide polymorphisms (SNPs) across breeds. The dog is of particular interest because it provides important evolutionary information and because existing breeds show great phenotypic diversity for morphological, physiological and behavioural traits. We use sequence comparison with the primate and rodent lineages to shed light on the structure and evolution of genomes and genes. Notably, the majority of the most highly conserved non-coding sequences in mammalian genomes are clustered near a small subset of genes with important roles in development. Analysis of SNPs reveals long-range haplotypes across the entire dog genome, and defines the nature of genetic diversity within and across breeds. The current SNP map now makes it possible for genome-wide association studies to identify genes responsible for diseases and traits, with important consequences for human and companion animal health.
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18.
  • Senapathi, Deepa, et al. (author)
  • Wild insect diversity increases inter-annual stability in global crop pollinator communities
  • 2021
  • In: Royal Society of London. Proceedings B. Biological Sciences. - : The Royal Society. - 1471-2954 .- 0962-8452. ; 288:1947
  • Journal article (peer-reviewed)abstract
    • While an increasing number of studies indicate that the range, diversity and abundance of many wild pollinators has declined, the global area of pollinator-dependent crops has significantly increased over the last few decades. Crop pollination studies to date have mainly focused on either identifying different guilds pollinating various crops, or on factors driving spatial changes and turnover observed in these communities. The mechanisms driving temporal stability for ecosystem functioning and services, however, remain poorly understood. Our study quantifies temporal variability observed in crop pollinators in 21 different crops across multiple years at a global scale. Using data from 43 studies from six continents, we show that (i) higher pollinator diversity confers greater inter-annual stability in pollinator communities, (ii) temporal variation observed in pollinator abundance is primarily driven by the three-most dominant species, and (iii) crops in tropical regions demonstrate higher inter-annual variability in pollinator species richness than crops in temperate regions. We highlight the importance of recognizing wild pollinator diversity in agricultural landscapes to stabilize pollinator persistence across years to protect both biodiversity and crop pollination services. Short-term agricultural management practices aimed at dominant species for stabilizing pollination services need to be considered alongside longer term conservation goals focussed on maintaining and facilitating biodiversity to confer ecological stability.
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19.
  • Shellock, R. J., et al. (author)
  • Building leaders for the UN Ocean Science Decade : a guide to supporting early career women researchers within academic marine research institutions
  • 2023
  • In: ICES Journal of Marine Science. - : Oxford University Press (OUP). - 1054-3139 .- 1095-9289. ; 80:1, s. 56-75
  • Journal article (peer-reviewed)abstract
    • Diverse and inclusive marine research is paramount to addressing ocean sustainability challenges in the 21st century, as envisioned by the UN Decade of Ocean Science for Sustainable Development. Despite increasing efforts to diversify ocean science, women continue to face barriers at various stages of their career, which inhibits their progression to leadership within academic institutions. In this perspective, we draw on the collective experiences of thirty-four global women leaders, bolstered by a narrative review, to identify practical strategies and actions that will help empower early career women researchers to become the leaders of tomorrow. We propose five strategies: (i) create a more inclusive culture, (ii) ensure early and equitable career development opportunities for women ECRs, (iii) ensure equitable access to funding for women ECRs, (iv) offer mentoring opportunities and, (v) create flexible, family-friendly environments. Transformational, meaningful, and lasting change will only be achieved through commitment and collaborative action across various scales and by multiple stakeholders. 
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20.
  • Walker, M. D., et al. (author)
  • Plant community responses to experimental warming across the tundra biome
  • 2006
  • In: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 103:5, s. 1342-1346
  • Journal article (peer-reviewed)abstract
    • Recent observations of changes in some tundra ecosystems appear to be responses to a warming climate. Several experimental studies have shown that tundra plants and ecosystems can respond strongly to environmental change, including warming; however, most studies were limited to a single location and were of short duration and based on a variety of experimental designs. In addition, comparisons among studies are difficult because a variety of techniques have been used to achieve experimental warming and different measurements have been used to assess responses. We used metaanalysis on plant community measurements from standardized warming experiments at 11 locations across the tundra biome involved in the International Tundra Experiment. The passive warming treatment increased plant-level air temperature by 1-3 degrees C, which is in the range of predicted and observed warming for tundra regions. Responses were rapid and detected in whole plant communities after only two growing seasons. Overall, warming increased height and cover of deciduous shrubs and graminoids, decreased cover of mosses and lichens, and decreased species diversity and evenness. These results predict that warming will cause a decline in biodiversity across a wide variety of tundra, at least in the short term. They also provide rigorous experimental evidence that recently observed increases in shrub cover in many tundra regions are in response to climate warming. These changes have important implications for processes and interactions within tundra ecosystems and between tundra and the atmosphere.
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21.
  • Zheng, Y. X., et al. (author)
  • Winter seal-based observations reveal glacial meltwater surfacing in the southeastern Amundsen Sea
  • 2021
  • In: Communications Earth & Environment. - : Springer Science and Business Media LLC. - 2662-4435. ; 2:1
  • Journal article (peer-reviewed)abstract
    • Determining the injection of glacial meltwater into polar oceans is crucial for quantifying the climate system response to ice sheet mass loss. However, meltwater is poorly observed and its pathways poorly known, especially in winter. Here we present winter meltwater distribution near Pine Island Glacier using data collected by tagged seals, revealing a highly variable meltwater distribution with two meltwater-rich layers in the upper 250m and at around 450m, connected by scattered meltwater-rich columns. We show that the hydrographic signature of meltwater is clearest in winter, when its presence can be unambiguously mapped. We argue that the buoyant meltwater provides near-surface heat that helps to maintain polynyas close to ice shelves. The meltwater feedback onto polynyas and air-sea heat fluxes demonstrates that although the processes determining the distribution of meltwater are small-scale, they are important to represent in Earth system models. A highly variable meltwater distribution with interlinked layers and columns is found in the Amundsen Sea in winter, and it may sustain polynyas in the region, according to hydrographic data obtained by seals.
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22.
  • Åkesson, Torsten, et al. (author)
  • Towards the european strategy for particle physics: The briefing book
  • 2007
  • In: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 51:2, s. 421-500
  • Research review (peer-reviewed)abstract
    • This document was prepared as part of the briefing material for the Workshop of the CERN Council Strategy Group, held in DESY Zeuthen from 2nd to 6th May 2006. It gives an overview of the physics issues and of the technological challenges that will shape the future of the field, and incorporates material presented and discussed during the Symposium on the European Strategy for Particle Physics, held in Orsay from 30th January to 2nd February 2006, reflecting the various opinions of the European community as recorded in written submissions to the Strategy Group and in the discussions at the Symposium.
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23.
  • Álvarez Asencio, Rubén, et al. (author)
  • Nanotribology : Tribotronics, ionic liquids and control of surface interactions
  • 2013
  • In: 5th World Tribology Congress, WTC 2013. ; , s. 3106-3108
  • Conference paper (peer-reviewed)abstract
    • The interfacial ordering of Ionic liquids leads to interesting nanotribological properties as revealed by colloid probe studies. The first of these is the clear correlation between the number of ion pairs trapped in the tribological contact and the friction coefficient displayed. The second is the fact that the surface electrical potential can be used to control the composition of the boundary layer and thus tune the friction. Thirdly, the interfacial ordering appears to significantly affect the fluid dynamics over large distances.
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24.
  • Azaneu, M., et al. (author)
  • Influence of Shelf Break Processes on the Transport of Warm Waters Onto the Eastern Amundsen Sea Continental Shelf
  • 2023
  • In: Journal of Geophysical Research-Oceans. - 2169-9275. ; 128:5
  • Journal article (peer-reviewed)abstract
    • The heat transported onto the continental shelf by Circumpolar Deep Water (CDW) is the main driver of ice shelf basal melting in the Amundsen Sea. Here, we investigate the slope current system and the variability of the heat transported through the Pine Island-Thwaites central and eastern troughs using data from five moorings deployed in the region between 5 March 2012 and 7 February 2016. Substantial variability on intermonthly time scales (3-4 months) is observed in the onshore heat flux, driven primarily by zonal wind stress north of the shelf break. Heat content, onshore flow, and heat flux are highly correlated between central and eastern troughs, which are most likely dynamically linked by the zonal wind stress forcing. This is the first time this dynamic link between troughs is observed. In the eastern the Amundsen Sea, during the El Nino of 2015/2016, strong eastward winds led to lower temperatures over the continental shelf while the onshore heat flux is intensified. We hypothesize that this anti-correlation between heat content and heat flux results from a strengthened eastward undercurrent leading to upwelling of a colder and deeper CDW variety. These results highlight the complex and heterogeneous response of this region to environmental and the importance of velocity data for understanding the dynamics in this region. It also suggests that the hypothesized link between large-scale atmospheric forcing (e.g., El Nino-Southern Oscillation) and ice-shelf melt is not produced via changes in heat content, but instead via changes in onshore heat flux.
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25.
  • Baker, A M R, et al. (author)
  • Energy loss rates of hot Dirac fermions in epitaxial, exfoliated, and CVD graphene
  • 2013
  • In: Physical Review B. Condensed Matter and Materials Physics. - : American Physical Society. - 1098-0121 .- 1550-235X .- 2469-9950 .- 2469-9969. ; 87:4, s. 045414-
  • Journal article (peer-reviewed)abstract
    • Energy loss rates for hot carriers in graphene have been measured using graphene produced by epitaxial growth on SiC, exfoliation, and chemical vapor deposition (CVD). It is shown that the temperature dependence of the energy loss rates measured with high-field damped Shubnikov-de Haas oscillations and the temperature dependence of the weak localization peak close to zero field correlate well, with the high-field measurements understating the energy loss rates by similar to 40% compared to the low-field results. The energy loss rates for all graphene samples follow a universal scaling of T-e(4) at low temperatures and depend weakly on carrier density proportional to n(-1/2), evidence for enhancement of the energy loss rate due to disorder in CVD samples.
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26.
  • Baker, A M R, et al. (author)
  • Weak localization scattering lengths in epitaxial, and CVD graphene
  • 2012
  • In: Physical Review B. Condensed Matter and Materials Physics. - : American Physical Society. - 1098-0121 .- 1550-235X .- 2469-9950 .- 2469-9969. ; 86:23, s. 235441-
  • Journal article (peer-reviewed)abstract
    • Weak localization in graphene is studied as a function of carrier density in the range from 1 x 10(11) cm(-2) to 1.43 x 10(13) cm(-2) using devices produced by epitaxial growth onto SiC and CVD growth on thin metal film. The magnetic field dependent weak localization is found to be well fitted by theory, which is then used to analyze the dependence of the scattering lengths L-phi, L-i, and L-* on carrier density. We find no significant carrier dependence for L-phi, a weak decrease for L-i with increasing carrier density just beyond a large standard error, and a n(-1/4) dependence for L-*. We demonstrate that currents as low as 0.01 nA are required in smaller devices to avoid hot-electron artifacts in measurements of the quantum corrections to conductivity. DOI: 10.1103/PhysRevB.86.235441
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28.
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29.
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30.
  • Bretscher, Hope, et al. (author)
  • Rational Passivation of Sulfur Vacancy Defects in Two-Dimensional Transition Metal Dichalcogenides
  • 2021
  • In: ACS Nano. - : American Chemical Society (ACS). - 1936-0851 .- 1936-086X. ; 15:5, s. 8780-8789
  • Journal article (peer-reviewed)abstract
    • Structural defects vary the optoelectronic properties of monolayer transition metal dichalcogenides, leading to concerted efforts to control defect type and density via materials growth or postgrowth passivation. Here, we explore a simple chemical treatment that allows on-off switching of low-lying, defect-localized exciton states, leading to tunable emission properties. Using steady-state and ultrafast optical spectroscopy, supported by ab initio calculations, we show that passivation of sulfur vacancy defects, which act as exciton traps in monolayer MoS2 and WS2, allows for controllable and improved mobilities and an increase in photoluminescence up to 275-fold, more than twice the value achieved by other chemical treatments. Our findings suggest a route for simple and rational defect engineering strategies for tunable and switchable electronic and excitonic properties through passivation.
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31.
  • Cooper, P. K., et al. (author)
  • Tribotronic control of friction in oil-based lubricants with ionic liquid additives
  • 2016
  • In: Physical Chemistry, Chemical Physics - PCCP. - : Royal Society of Chemistry (RSC). - 1463-9076 .- 1463-9084. ; 18:34, s. 23657-23662
  • Journal article (peer-reviewed)abstract
    • Atomic force microscopy (AFM) reveals that tribotronic control of friction using an external potential applied to a gold surface is possible for ionic liquid (IL) concentrations as low as 5 mol% in hexadecane. The IL used is trihexyl(tetradecyl) phosphonium bis(2,4,4-trimethylpentyl)phosphinate, in which both the cation and anion have surfactant-like structures, and is miscible with hexadecane in all proportions. For IL concentrations less than 5 mol% friction does not vary with applied potential, but for 5 mol% and above changing the potential changes the composition of the IL boundary layer from cation-enriched (negative potentials) to anion-enriched (positive potentials). As the lubricities of the cation-rich and anion-rich boundary layers differ, this enables active control of friction in oil-based lubricants.
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32.
  • Elbourne, Aaron, et al. (author)
  • Adsorbed and near-surface structure of ionic liquids determines nanoscale friction
  • 2013
  • In: Chemical Communications. - : Royal Society of Chemistry (RSC). - 1359-7345 .- 1364-548X. ; 49:60, s. 6797-6799
  • Journal article (peer-reviewed)abstract
    • Surface-adsorbed and near-surface ion layer structure controls nanotribology in the silica-propylammonium nitrate (PAN)-mica system. Atomic Force Microscopy (AFM) imaging and normal force curves reveal that the normal load dictates the number of interfacial ion layers and the lateral layer structure. Shear force measurements show the lubricity of the interface changes with the number, and lateral structure, of the confined ion layer(s).
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33.
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34.
  • Mikkelsen, Tarjei S, et al. (author)
  • Genome of the marsupial Monodelphis domestica reveals innovation in non-coding sequences
  • 2007
  • In: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 447:7141, s. 167-177
  • Journal article (peer-reviewed)abstract
    • We report a high-quality draft of the genome sequence of the grey, short-tailed opossum (Monodelphis domestica). As the first metatherian ('marsupial') species to be sequenced, the opossum provides a unique perspective on the organization and evolution of mammalian genomes. Distinctive features of the opossum chromosomes provide support for recent theories about genome evolution and function, including a strong influence of biased gene conversion on nucleotide sequence composition, and a relationship between chromosomal characteristics and X chromosome inactivation. Comparison of opossum and eutherian genomes also reveals a sharp difference in evolutionary innovation between protein-coding and non-coding functional elements. True innovation in protein-coding genes seems to be relatively rare, with lineage-specific differences being largely due to diversification and rapid turnover in gene families involved in environmental interactions. In contrast, about 20% of eutherian conserved non-coding elements (CNEs) are recent inventions that postdate the divergence of Eutheria and Metatheria. A substantial proportion of these eutherian-specific CNEs arose from sequence inserted by transposable elements, pointing to transposons as a major creative force in the evolution of mammalian gene regulation.
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35.
  • Mullett, Martin S., et al. (author)
  • Phylogeography, origin and population structure of the self-fertile emerging plant pathogen Phytophthora pseudosyringae
  • 2024
  • In: Molecular plant pathology. - : John Wiley & Sons. - 1464-6722 .- 1364-3703. ; 25:4
  • Journal article (peer-reviewed)abstract
    • Phytophthora pseudosyringae is a self-fertile pathogen of woody plants, particularly associated with tree species from the genera Fagus, Notholithocarpus, Nothofagus and Quercus, which is found across Europe and in parts of North America and Chile. It can behave as a soil pathogen infecting roots and the stem collar region, as well as an aerial pathogen infecting leaves, twigs and stem barks, causing particular damage in the United Kingdom and western North America. The population structure, migration and potential outcrossing of a worldwide collection of isolates were investigated using genotyping-by-sequencing. Coalescent-based migration analysis revealed that the North American population originated from Europe. Historical gene flow has occurred between the continents in both directions to some extent, yet contemporary migration is overwhelmingly from Europe to North America. Two broad population clusters dominate the global population of the pathogen, with a subgroup derived from one of the main clusters found only in western North America. Index of association and network analyses indicate an influential level of outcrossing has occurred in this preferentially inbreeding, homothallic oomycete. Outcrossing between the two main population clusters has created distinct subgroups of admixed individuals that are, however, less common than the main population clusters. Differences in life history traits between the two main population clusters should be further investigated together with virulence and host range tests to evaluate the risk each population poses to natural environments worldwide.
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36.
  • Pinto, Dalila, et al. (author)
  • Functional impact of global rare copy number variation in autism spectrum disorders.
  • 2010
  • In: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 466:7304, s. 368-372
  • Journal article (peer-reviewed)abstract
    • The autism spectrum disorders (ASDs) are a group of conditions characterized by impairments in reciprocal social interaction and communication, and the presence of restricted and repetitive behaviours. Individuals with an ASD vary greatly in cognitive development, which can range from above average to intellectual disability. Although ASDs are known to be highly heritable ( approximately 90%), the underlying genetic determinants are still largely unknown. Here we analysed the genome-wide characteristics of rare (<1% frequency) copy number variation in ASD using dense genotyping arrays. When comparing 996 ASD individuals of European ancestry to 1,287 matched controls, cases were found to carry a higher global burden of rare, genic copy number variants (CNVs) (1.19 fold, P = 0.012), especially so for loci previously implicated in either ASD and/or intellectual disability (1.69 fold, P = 3.4 x 10(-4)). Among the CNVs there were numerous de novo and inherited events, sometimes in combination in a given family, implicating many novel ASD genes such as SHANK2, SYNGAP1, DLGAP2 and the X-linked DDX53-PTCHD1 locus. We also discovered an enrichment of CNVs disrupting functional gene sets involved in cellular proliferation, projection and motility, and GTPase/Ras signalling. Our results reveal many new genetic and functional targets in ASD that may lead to final connected pathways.
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37.
  • Putman, B, et al. (author)
  • Risk factors for post-9/11 chronic rhinosinusitis in Fire Department of the City of New York workers
  • 2018
  • In: Occupational and environmental medicine. - : BMJ. - 1470-7926 .- 1351-0711. ; 75:12, s. 884-889
  • Journal article (peer-reviewed)abstract
    • Chronic rhinosinusitis (CRS) has high socioeconomic burden but underexplored risk factors. The collapse of the World Trade Center (WTC) towers on 11 September 2001 (9/11) caused dust and smoke exposure, leading to paranasal sinus inflammation and CRS. We aim to determine which job tasks are risk factors for CRS in WTC-exposed Fire Department of the City of New York (FDNY) firefighters and emergency medical services (EMS) workers.MethodsThis cohort study included a 16-year follow-up of 11 926 WTC-exposed FDNY rescue/recovery workers with data on demographics, WTC exposure, job tasks and first post-9/11 complete blood counts. Using multivariable Cox regression, we assessed the associations of WTC exposure, work assignment (firefighter/EMS), digging and rescue tasks at the WTC site and blood eosinophil counts with subsequent CRS, adjusting for potential confounders.ResultsThe rate of CRS was higher in firefighters than EMS (1.80/100 person-years vs 0.70/100 person-years; p<0.001). The combination of digging and rescue work was a risk factor for CRS (HR 1.54, 95% CI 1.23 to 1.94, p<0.001) independent of work assignment and WTC exposure.ConclusionsCompared with EMS, firefighters were more likely to engage in a combination of digging and rescue work, which was a risk factor for CRS. Chronic irritant exposures associated with digging and rescue work may account for higher post-9/11 CRS rates among firefighters.
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38.
  • Riegel, Barbara, et al. (author)
  • Self-care research : Where are we now? Where are we going?
  • 2021
  • In: International Journal of Nursing Studies. - : PERGAMON-ELSEVIER SCIENCE LTD. - 0020-7489 .- 1873-491X. ; 116
  • Journal article (peer-reviewed)abstract
    • Background and objective: The beneficial effects of self-care include improved well-being and lower morbidity, mortality, and healthcare costs. In this article we address the current state of self-care research and propose an agenda for future research based on the inaugural conference of the International Center for Self-Care Research held in Rome, Italy in June 2019. The vision of this Center is a world where self-care is prioritized by individuals, families, and communities and is the first line of approach in every health care encounter. The mission of the Center is to lead the self-care research endeavor, improving conceptual clarity and promoting interdisciplinary work informed by a shared vision addressing knowledge gaps. A focused research agenda can deepen our theoretical understanding of self-care and the mechanisms underlying self-care, which can contribute to the development of effective interventions that improve outcomes. Methods: During conference discussions, we identified seven major reasons why self-care is challenging, which can be grouped into the general categories of behavior change and illness related factors. We identified six specific knowledge gaps that, if addressed, may help to address these challenges: the influence of habit formation on behavior change, resilience in the face of stressful life events that interfere with self-care, the influence of culture on self-care behavioral choices, the difficulty performing self-care with multiple chronic conditions, self-care in persons with severe mental illness, and the influence of others (care partners, family, peer supporters, and healthcare professionals) on self-care. Plans to achieve results: To achieve the vision and mission of the Center, we will lead a collaborative program of research that addresses self-care knowledge gaps and improves outcomes, create a supportive international network for knowledge transfer and support of innovations in self-care research, and support and train others in self-care research. Beyond these specific short-term goals, important policy implications of this work are discussed. (c) 2019 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license ( http://creativecommons.org/licenses/by-nc-nd/4.0/ )
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39.
  • Seale, A N, et al. (author)
  • Pulmonary vein stenosis: the UK, Ireland and Sweden collaborative study.
  • 2009
  • In: Heart (British Cardiac Society). - : BMJ. - 1468-201X .- 1355-6037. ; 95:23, s. 1944-9
  • Journal article (peer-reviewed)abstract
    • OBJECTIVE: To describe clinical features, morphology, management and outcome of pulmonary vein stenosis (PVS) in childhood. DESIGN AND SETTING: Retrospective international collaborative study involving 19 paediatric cardiology centres in the UK, Ireland and Sweden. PATIENTS: Cases of PVS presenting between 1 January 1995 and 31 December 2004 were identified. Cases where pulmonary veins connected to a morphological left atrium were included. Functionally univentricular hearts and total anomalous pulmonary venous connection were excluded. All available data and imaging were reviewed. RESULTS: 58 cases were identified. In 22 cases (38%) there was premature delivery. 46 (79%) had associated cardiac lesions; 16 (28%) had undergone previous cardiac surgery before PVS diagnosis. 16 children (28%) had a syndrome or significant extracardiac abnormality. 36 presented with unilateral disease of which 86% was on the left. Where there was adequate sequential imaging, disease progression was shown with discrete stenosis leading to diffusely small pulmonary veins. Collateral vessels often developed. 13 patients had no intervention. Initial intervention was by catheter in 17 and surgery in 28. Overall 3-year survival was 49% (95% CI 35% to 63%) with patients undergoing initial surgical intervention having greater freedom from death or re-intervention (hazard ratio 0.44, 95% CI 0.2 to 0.99, p = 0.023). CONCLUSIONS: PVS is a complex disease of uncertain cause and frequently associated with prematurity. Early intervention may be indicated to deter irreversible secondary changes.
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40.
  • Sweeney, James, et al. (author)
  • Control of Nanoscale Friction on Gold in an Ionic Liquid by a Potential-Dependent Ionic Lubricant Layer
  • 2012
  • In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 109:15, s. 155502-
  • Journal article (peer-reviewed)abstract
    • The lubricating properties of an ionic liquid on gold surfaces can be controlled through application of an electric potential to the sliding contact. A nanotribology approach has been used to study the frictional behavior of 1-butyl-1-methylpyrrolidinium tris(pentafluoroethyl) trifluorophosphate ([Py-1,Py-4]FAP) confined between silica colloid probes or sharp silica tips and a Au(111) substrate using atomic force microscopy. Friction forces vary with potential because the composition of a confined ion layer between the two surfaces changes from cation-enriched (at negative potentials) to anion-enriched (at positive potentials). This offers a new approach to tuning frictional forces reversibly at the molecular level without changing the substrates, employing a self-replenishing boundary lubricant of low vapor pressure.
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41.
  • Sweeney, James, et al. (author)
  • Effect of ion structure on nanoscale friction in protic ionic liquids
  • 2014
  • In: Physical Chemistry, Chemical Physics - PCCP. - : Royal Society of Chemistry (RSC). - 1463-9076 .- 1463-9084. ; 16:31, s. 16651-16658
  • Journal article (peer-reviewed)abstract
    • The effect of ionic liquid (IL) molecular structure on nanoscale friction has been investigated using colloidal probe Friction Force Microscopy (FFM). The ILs studied were ethylammonium formate (EAF), ethylammonium nitrate (EAN), propylammonium formate (PAF), propylammonium nitrate (PAN), dimethylethylammonium formate (DMEAF), and ethanolammonium nitrate (EtAN). ILs were confined between a silica colloid probe and a mica surface, and the friction force was measured as a function of normal load for sliding velocities between 10 and 40 mu m s(-1). At low normal forces, multiple IL layers are found between the probe and the surface, but at higher force, in the boundary layer regime, a single ion layer separates the probe and the surface. In the boundary layer regime energy is dissipated by two main pathways. Firstly, the ionic liquid near the surface, with the exception of the boundary layer, is expelled from the advancing contact made by the probe on the surface. This disruption in the interactions between the boundary layer and the near surface multilayers, leads to energy dissipation and depends on the strength of the attraction between the boundary and near surface layers. The second pathway is via rotations and twists of ions in the boundary layer, primarily associated with the cation terminal methyl group. The friction coefficient did not vary over the limited range of sliding speeds investigated.
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42.
  • Toreti, A, et al. (author)
  • Narrowing uncertainties in the effects of elevated CO2 on crops
  • 2020
  • In: Nature Food. - : Springer Science and Business Media LLC. - 2662-1355. ; 1, s. 775-782
  • Journal article (peer-reviewed)abstract
    • Plant responses to rising atmospheric carbon dioxide (CO2) concentrations, together with projected variations in temperature and precipitation will determine future agricultural production. Estimates of the impacts of climate change on agriculture provide essential information to design effective adaptation strategies, and develop sustainable food systems. Here, we review the current experimental evidence and crop models on the effects of elevated CO2 concentrations. Recent concerted efforts have narrowed the uncertainties in CO2-induced crop responses so that climate change impact simulations omitting CO2 can now be eliminated. To address remaining knowledge gaps and uncertainties in estimating the effects of elevated CO2 and climate change on crops, future research should expand experiments on more crop species under a wider range of growing conditions, improve the representation of responses to climate extremes in crop models, and simulate additional crop physiological processes related to nutritional quality.
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43.
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44.
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45.
  • Webber, B. G. M., et al. (author)
  • The Impact of Overturning and Horizontal Circulation in Pine Island Trough on Ice Shelf Melt in the Eastern Amundsen Sea
  • 2019
  • In: Journal of Physical Oceanography. - : American Meteorological Society. - 0022-3670 .- 1520-0485. ; 49:1, s. 63-83
  • Journal article (peer-reviewed)abstract
    • The ice shelves around the Amundsen Sea are rapidly melting as a result of the circulation of relatively warm ocean water into their cavities. However, little is known about the processes that determine the variability of this circulation. Here we use an ocean circulation model to diagnose the relative importance of horizontal and vertical (overturning) circulation within Pine Island Trough, leading to Pine Island and Thwaites ice shelves. We show that melt rates and southward Circumpolar Deep Water (CDW) transports covary over large parts of the continental shelf at interannual to decadal time scales. The dominant external forcing mechanism for this variability is Ekman pumping and suction on the continental shelf and at the shelf break, in agreement with previous studies. At the continental shelf break, the southward transport of CDW and heat is predominantly barotropic. Farther south within Pine Island Trough, northward and southward barotropic heat transports largely cancel, and the majority of the net southward temperature transport is facilitated by baroclinic and overturning circulations. The overturning circulation is related to water mass transformation and buoyancy gain on the shelf that is primarily facilitated by freshwater input from basal melting.
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46.
  • Winters, Maike, et al. (author)
  • Debunking highly prevalent health misinformation using audio dramas delivered by WhatsApp : evidence from a randomised controlled trial in Sierra Leone
  • 2021
  • In: BMJ Global Health. - : BMJ Publishing Group Ltd. - 2059-7908. ; 6:11
  • Journal article (peer-reviewed)abstract
    • Introduction Infectious disease misinformation is widespread and poses challenges to disease control. There is limited evidence on how to effectively counter health misinformation in a community setting, particularly in low-income regions, and unsettled scientific debate about whether misinformation should be directly discussed and debunked, or implicitly countered by providing scientifically correct information.Methods The Contagious Misinformation Trial developed and tested interventions designed to counter highly prevalent infectious disease misinformation in Sierra Leone, namely the beliefs that (1) mosquitoes cause typhoid and (2) typhoid co-occurs with malaria. The information intervention for group A (n=246) explicitly discussed misinformation and explained why it was incorrect and then provided the scientifically correct information. The intervention for group B (n=245) only focused on providing correct information, without directly discussing related misinformation. Both interventions were delivered via audio dramas on WhatsApp that incorporated local cultural understandings of typhoid. Participants were randomised 1:1:1 to the intervention groups or the control group (n=245), who received two episodes about breast feeding.Results At baseline 51% believed that typhoid is caused by mosquitoes and 59% believed that typhoid and malaria always co-occur. The endline survey was completed by 91% of participants. Results from the intention-to-treat, per-protocol and as-treated analyses show that both interventions substantially reduced belief in misinformation compared with the control group. Estimates from these analyses, as well as an exploratory dose–response analysis, suggest that direct debunking may be more effective at countering misinformation. Both interventions improved people’s knowledge and self-reported behaviour around typhoid risk reduction, and yielded self-reported increases in an important preventive method, drinking treated water.Conclusion These results from a field experiment in a community setting show that highly prevalent health misinformation can be countered, and that direct, detailed debunking may be most effective.Trial registration number NCT04112680.
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47.
  • Zheng, Y. X., et al. (author)
  • Reversal of ocean gyres near ice shelves in the Amundsen Sea caused by the interaction of sea ice and wind
  • 2022
  • In: Cryosphere. - : Copernicus GmbH. - 1994-0416. ; 16:7, s. 3005-3019
  • Journal article (peer-reviewed)abstract
    • Floating ice shelves buttress the Antarctic Ice Sheet, which is losing mass rapidly mainly due to ocean-driven melting and the associated disruption to glacial dynamics. The local ocean circulation near ice shelves is therefore important for the prediction of future ice mass loss and related sea-level rise as it determines the water mass exchange, heat transport under the ice shelf and resultant melting. However, the dynamics controlling the near-coastal circulation are not fully understood. A cyclonic (i.e. clockwise) gyre circulation (27 km radius) in front of the Pine Island Ice Shelf has previously been identified in both numerical models and velocity observations. Mooring data further revealed a potential reversal of this gyre during an abnormally cold period. Here we present ship-based observations from 2019 to the west of Thwaites Ice Shelf, revealing another gyre (13 km radius) for the first time in this habitually ice-covered region, rotating in the opposite (anticyclonic, anticlockwise) direction to the gyre near Pine Island Ice Shelf, despite similar wind forcing. We use an idealised configuration of MITgcm, with idealised forcing based on ERA5 climatological wind fields and a range of idealised sea ice conditions typical for the region, to reproduce key features of the observed gyres near Pine Island Ice Shelf and Thwaites Ice Shelf. The model driven solely by wind forcing in the presence of ice can reproduce the horizontal structure and direction of both gyres. We show that the modelled gyre direction depends upon the spatial difference in the ocean surface stress, which can be affected by the applied wind stress curl filed, the percentage of wind stress transferred through the ice, and the angle between the wind direction and the sea ice edge. The presence of ice, either it is fast ice/ice shelves blocking the effect of wind or mobile sea ice enhancing the effect of wind, has the potential to reverse the gyre direction relative to ice-free conditions.
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