564 research outputs found

    Toward City-Scale Litter Monitoring using Autonomous Ground Vehicles

    Get PDF
    Littering is a significant challenge for environmental sustainability and a major burden for cities and densely populated areas. Current solutions for litter monitoring, such as litter watch campaigns and city-operated litter collection, are costly and challenging to conduct at large-scale. This paper presents a vision for using autonomous ground vehicles (AGVs) for litter monitoring and removal and introduces a mechanism for AGVs that uses thermal dissipation resulting from sunlight to identify and remove litter objects. We identify and highlight key challenges for deploying the envisioned solution on a city-scale, and demonstrate the feasibility of the solution through extensive experiments.Peer reviewe

    Diagnostic value of MRI-based PSA density in predicting transperineal sector-guided prostate biopsy outcomes

    Get PDF
    PURPOSE: Prostate-specific antigen (PSA) density (PSAD) has potential to increase the diagnostic utility of PSA, yet has had poor uptake in clinical practice. We aimed to determine the diagnostic value of magnetic resonance imaging-derived PSAD (MR-PSAD) in predicting transperineal sector-guided prostate biopsy (TPSB) outcomes. MATERIALS AND METHODS: Men presenting for primary TPSB from 2007 to 2014 were considered. Histological outcomes were assessed and defined as: presence of any cancer or significant cancer defined as presence of Gleason 4 and/or maximum tumour core length (MCCL) ≥ 4 mm (G4); or Gleason 4 and/or MCCL ≥ 6 mm (G6). Sensitivity, specificity and positive and negative predictive values were calculated, and receiver operating characteristics (ROC) curves were generated to compare MR-PSAD and PSA. RESULTS: Six hundred fifty-nine men were evaluated with mean age 62.5 ± 9 years, median PSA 6.7 ng/ml (range 0.5-40.0), prostate volume 40 cc (range 7-187) and MR-PSAD 0.15 ng/ml/cc (range 0.019-1.3). ROC area under the curve (95% CI) was significantly better for MR-PSAD than PSA for all cancer definitions (p < 0.001): 0.73 (0.70-0.76) versus 0.61 (0.57-0.64) for any cancer; 0.75 (0.71-0.78) versus 0.66 (0.62-0.69) for G4; and 0.77 (0.74-0.80) versus 0.68 (0.64-0.71) for G6. Sensitivities for MR-PSAD < 0.1 ng/ml/cc were 85.0, 89.9 and 91.9% for any, G4 and G6 cancer, respectively. CONCLUSION: MR-PSAD may be better than total PSA in determining risk of positive biopsy outcome. Its use may improve risk stratification and reduce unnecessary biopsies

    An AP-MS- and BioID-compatible MAC-tag enables comprehensive mapping of protein interactions and subcellular localizations

    Get PDF
    Protein-protein interactions govern almost all cellular functions. These complex networks of stable and transient associations can be mapped by affinity purification mass spectrometry (AP-MS) and complementary proximity-based labeling methods such as BioID. To exploit the advantages of both strategies, we here design and optimize an integrated approach combining AP-MS and BioID in a single construct, which we term MAC-tag. We systematically apply the MAC-tag approach to 18 subcellular and 3 sub-organelle localization markers, generating a molecular context database, which can be used to define a protein's molecular location. In addition, we show that combining the AP-MS and BioID results makes it possible to obtain interaction distances within a protein complex. Taken together, our integrated strategy enables the comprehensive mapping of the physical and functional interactions of proteins, defining their molecular context and improving our understanding of the cellular interactome.Peer reviewe

    Doyne lecture 2016:intraocular health and the many faces of inflammation

    Get PDF
    Dogma for reasons of immune privilege including sequestration (sic) of ocular antigen, lack of lymphatic and immune competent cells in the vital tissues of the eye has long evaporated. Maintaining tissue and cellular health to preserve vision requires active immune responses to prevent damage and respond to danger. A priori the eye must contain immune competent cells, undergo immune surveillance to ensure homoeostasis as well as an ability to promote inflammation. By interrogating immune responses in non-infectious uveitis and compare with age-related macular degeneration (AMD), new concepts of intraocular immune health emerge. The role of macrophage polarisation in the two disorders is a tractable start. TNF-alpha regulation of macrophage responses in uveitis has a pivotal role, supported via experimental evidence and validated by recent trial data. Contrast this with the slow, insidious degeneration in atrophic AMD or in neovasular AMD, with the compelling genetic association with innate immunity and complement, highlights an ability to attenuate pathogenic immune responses and despite known inflammasome activation. Yolk sac-derived microglia maintains tissue immune health. The result of immune cell activation is environmentally dependent, for example, on retinal cell bioenergetics status, autophagy and oxidative stress, and alterations that skew interaction between macrophages and retinal pigment epithelium (RPE). For example, dead RPE eliciting macrophage VEGF secretion but exogenous IL-4 liberates an anti-angiogenic macrophage sFLT-1 response. Impaired autophagy or oxidative stress drives inflammasome activation, increases cytotoxicity, and accentuation of neovascular responses, yet exogenous inflammasome-derived cytokines, such as IL-18 and IL-33, attenuate responses

    Revealing the short-range structure of the "mirror nuclei" 3^3H and 3^3He

    Full text link
    When protons and neutrons (nucleons) are bound into atomic nuclei, they are close enough together to feel significant attraction, or repulsion, from the strong, short-distance part of the nucleon-nucleon interaction. These strong interactions lead to hard collisions between nucleons, generating pairs of highly-energetic nucleons referred to as short-range correlations (SRCs). SRCs are an important but relatively poorly understood part of nuclear structure and mapping out the strength and isospin structure (neutron-proton vs proton-proton pairs) of these virtual excitations is thus critical input for modeling a range of nuclear, particle, and astrophysics measurements. Hitherto measurements used two-nucleon knockout or ``triple-coincidence'' reactions to measure the relative contribution of np- and pp-SRCs by knocking out a proton from the SRC and detecting its partner nucleon (proton or neutron). These measurementsshow that SRCs are almost exclusively np pairs, but had limited statistics and required large model-dependent final-state interaction (FSI) corrections. We report on the first measurement using inclusive scattering from the mirror nuclei 3^3H and 3^3He to extract the np/pp ratio of SRCs in the A=3 system. We obtain a measure of the np/pp SRC ratio that is an order of magnitude more precise than previous experiments, and find a dramatic deviation from the near-total np dominance observed in heavy nuclei. This result implies an unexpected structure in the high-momentum wavefunction for 3^3He and 3^3H. Understanding these results will improve our understanding of the short-range part of the N-N interaction

    Comparing proton momentum distributions in A=2A=2 and 3 nuclei via 2^2H 3^3H and 3^3He (e,ep)(e, e'p) measurements

    Full text link
    We report the first measurement of the (e,ep)(e,e'p) reaction cross-section ratios for Helium-3 (3^3He), Tritium (3^3H), and Deuterium (dd). The measurement covered a missing momentum range of 40pmiss55040 \le p_{miss} \le 550 MeV/c/c, at large momentum transfer (Q21.9\langle Q^2 \rangle \approx 1.9 (GeV/c/c)2^2) and xB>1x_B>1, which minimized contributions from non quasi-elastic (QE) reaction mechanisms. The data is compared with plane-wave impulse approximation (PWIA) calculations using realistic spectral functions and momentum distributions. The measured and PWIA-calculated cross-section ratios for 3^3He/d/d and 3^3H/d/d extend to just above the typical nucleon Fermi-momentum (kF250k_F \approx 250 MeV/c/c) and differ from each other by 20%\sim 20\%, while for 3^3He/3^3H they agree within the measurement accuracy of about 3\%. At momenta above kFk_F, the measured 3^3He/3^3H ratios differ from the calculation by 20%50%20\% - 50\%. Final state interaction (FSI) calculations using the generalized Eikonal Approximation indicate that FSI should change the 3^3He/3^3H cross-section ratio for this measurement by less than 5\%. If these calculations are correct, then the differences at large missing momenta between the 3^3He/3^3H experimental and calculated ratios could be due to the underlying NNNN interaction, and thus could provide new constraints on the previously loosely-constrained short-distance parts of the NNNN interaction.Comment: 8 pages, 3 figures (4 panels

    Strong Interaction Physics at the Luminosity Frontier with 22 GeV Electrons at Jefferson Lab

    Full text link
    This document presents the initial scientific case for upgrading the Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Lab (JLab) to 22 GeV. It is the result of a community effort, incorporating insights from a series of workshops conducted between March 2022 and April 2023. With a track record of over 25 years in delivering the world's most intense and precise multi-GeV electron beams, CEBAF's potential for a higher energy upgrade presents a unique opportunity for an innovative nuclear physics program, which seamlessly integrates a rich historical background with a promising future. The proposed physics program encompass a diverse range of investigations centered around the nonperturbative dynamics inherent in hadron structure and the exploration of strongly interacting systems. It builds upon the exceptional capabilities of CEBAF in high-luminosity operations, the availability of existing or planned Hall equipment, and recent advancements in accelerator technology. The proposed program cover various scientific topics, including Hadron Spectroscopy, Partonic Structure and Spin, Hadronization and Transverse Momentum, Spatial Structure, Mechanical Properties, Form Factors and Emergent Hadron Mass, Hadron-Quark Transition, and Nuclear Dynamics at Extreme Conditions, as well as QCD Confinement and Fundamental Symmetries. Each topic highlights the key measurements achievable at a 22 GeV CEBAF accelerator. Furthermore, this document outlines the significant physics outcomes and unique aspects of these programs that distinguish them from other existing or planned facilities. In summary, this document provides an exciting rationale for the energy upgrade of CEBAF to 22 GeV, outlining the transformative scientific potential that lies within reach, and the remarkable opportunities it offers for advancing our understanding of hadron physics and related fundamental phenomena.Comment: Updates to the list of authors; Preprint number changed from theory to experiment; Updates to sections 4 and 6, including additional figure

    Observation of the Rare Decay of the η Meson to Four Muons

    Get PDF
    A search for the rare η→μ+μ−μ+μ− double-Dalitz decay is performed using a sample of proton-proton collisions, collected by the CMS experiment at the CERN LHC with high-rate muon triggers during 2017 and 2018 and corresponding to an integrated luminosity of 101  fb−1. A signal having a statistical significance well in excess of 5 standard deviations is observed. Using the η→μ+μ− decay as normalization, the branching fraction B(η→μ+μ−μ+μ−)=[5.0±0.8(stat)±0.7(syst)±0.7(B2μ)]×10−9 is measured, where the last term is the uncertainty in the normalization channel branching fraction. This work achieves an improved precision of over 5 orders of magnitude compared to previous results, leading to the first measurement of this branching fraction, which is found to agree with theoretical predictions
    corecore