7,872 research outputs found

    Synthesis of the land carbon fluxes of the Amazon region between 2010 and 2020

    Get PDF
    The Amazon is the largest continuous tropical forest in the world and plays a key role in the global carbon cycle. Human-induced disturbances and climate change have impacted the Amazon carbon balance. Here we conduct a comprehensive synthesis of existing state-of-the-art estimates of the contemporary land carbon fluxes in the Amazon using a set of bottom-up methods (i.e., dynamic vegetation models and bookkeeping models) and a top-down inversion (atmospheric inversion model) over the Brazilian Amazon and the whole Biogeographical Amazon domain. Over the whole biogeographical Amazon region bottom-up methodologies suggest a small average carbon sink over 2010-2020, in contrast to a small carbon source simulated by top-down inversion (2010-2018). However, these estimates are not significantly different from one another when accounting for their large individual uncertainties, highlighting remaining knowledge gaps, and the urgent need to reduce such uncertainties. Nevertheless, both methodologies agreed that the Brazilian Amazon has been a net carbon source during recent climate extremes and that the south-eastern Amazon was a net land carbon source over the whole study period (2010-2020). Overall, our results point to increasing human-induced disturbances (deforestation and forest degradation by wildfires) and reduction in the old-growth forest sink during drought

    In situ estimation of ice crystal properties at the South Pole using LED calibration data from the IceCube Neutrino Observatory

    Get PDF
    The IceCube Neutrino Observatory instruments about 1 km3 of deep, glacial ice at the geographic South Pole. It uses 5160 photomultipliers to detect Cherenkov light emitted by charged relativistic particles. An unexpected light propagation effect observed by the experiment is an anisotropic attenuation, which is aligned with the local flow direction of the ice. We examine birefringent light propagation through the polycrystalline ice microstructure as a possible explanation for this effect. The predictions of a first-principles model developed for this purpose, in particular curved light trajectories resulting from asymmetric diffusion, provide a qualitatively good match to the main features of the data. This in turn allows us to deduce ice crystal properties. Since the wavelength of the detected light is short compared to the crystal size, these crystal properties include not only the crystal orientation fabric, but also the average crystal size and shape, as a function of depth. By adding small empirical corrections to this first-principles model, a quantitatively accurate description of the optical properties of the IceCube glacial ice is obtained. In this paper, we present the experimental signature of ice optical anisotropy observed in IceCube light-emitting diode (LED) calibration data, the theory and parameterization of the birefringence effect, the fitting procedures of these parameterizations to experimental data, and the inferred crystal properties.</p

    Ultra-trace element characterization of the central Ottawa River basin using a rapid, flexible, and low-volume ICP-MS method

    Get PDF
    Ultra-trace (<1 ng g-1) rare earth elements and yttrium (REE+Y) and high field strength element (HFSE) geochemistry of freshwater can constrain element sources, aqueous processes in hydrologic catchments, and the signature of dissolved terrestrial fluxes to the oceans. This study details an adapted method capable of quantifying ≄38 elements (including all REE+Y, Nb, Ta, Zr, Hf, Mo, W, Th, U) with minimal sample preparation in natural water aliquots as low as ≀2 mL. The method precision and accuracy are demonstrated using measurement of the National Research Council – Conseil national de recherches Canada (NRC-CNRC) river water certified reference material (CRM) SLRS-6 sampled from the Ottawa River (OR). Data from SLRS CRM are compared to those of new, filtered (HREE-enriched REE+Y patterns, small natural positive Y and Gd anomalies, and negative Eu and Ce anomalies. These REE+Y features are coherent downstream in the OR apart from amplification of Eu and Ce anomalies during REE removal/dilution. The OR samples capture a downstream decrease in sparingly soluble HFSE (Th, Nb, Ta, Zr, Hf), presumably related to their colloid-particulate removal from the dissolved load, accompanied by crustal Zr/Hf (32.5 ± 5.1) and supercrustal Nb/Ta (25.1 ± 7.7) ratios. Subcrustal Th/U (0.17-0.96) and supercrustal Mo/W (12.0-74.5) ratios in all ORB waters indicate preferential release and aqueous solubility of U>Th and Mo>W, with the latter attributed primarily to preferential W adsorption on soil or upstream aquatic (oxy)(hydr)oxide surfaces

    Criteria for the diagnosis of extra nodal extension detected on radiological imaging in head and neck cancer: HNCIG international consensus recommendations

    No full text
    Extranodal extension of tumour on histopathology (pENE) is known to be a negative prognostic factor in head and neck cancer (HNC). Compelling evidence suggests that extranodal extension detected on radiological imaging (imaging-detected ENE; iENE) is also a negative prognostic factor. Furthermore, if iENE could be identified reliably before start of treatment, it could be used to guide treatment selection, as patients with iENE may be better managed with non-surgical approaches to avoid the toxicity and cost of trimodality therapy. There are many aspects of iENE that remain unresolved or which lack consensus – such as the criteria to best diagnose iENE and the associated terminology. The Head and Neck Cancer International Group conducted a five-round modified Delphi process with a group of 18 international radiology experts, representing 14 national clinical research groups. We generated consensus recommendations on the terminology and diagnostic criteria for iENE to harmonize clinical practice and research. These recommendations have been endorsed by 19 national organisations, representing 34 countries. We propose a new classification system to aid diagnosis, which was supported by the majority of participating experts over existing systems, and which will require validation in the future. Additionally, we have created an online educational resource for grading iENE.<br/

    Challenges of developing robust AI for intrapartum fetal heart rate monitoring

    Get PDF
    Background: CTG remains the only non-invasive tool available to the maternity team for continuous monitoring of fetal well-being during labour. Despite widespread use and investment in staff training, difficulty with CTG interpretation continues to be identified as a problem in cases of fetal hypoxia, which often results in permanent brain injury. Given the recent advances in AI, it is hoped that its application to CTG will offer a better, less subjective and more reliable method of CTG interpretation. Objectives: This mini-review examines the literature and discusses the impediments to the success of AI application to CTG thus far. Prior randomised control trials (RCTs) of CTG decision support systems are reviewed from technical and clinical perspectives. A selection of novel engineering approaches, not yet validated in RCTs, are also reviewed. The review presents the key challenges that need to be addressed in order to develop a robust AI tool to identify fetal distress in a timely manner so that appropriate intervention can be made. Results: The decision support systems used in three RCTs were reviewed, summarising the algorithms, the outcomes of the trials and the limitations. Preliminary work suggests that the inclusion of clinical data can improve the performance of AI-assisted CTG. Combined with newer approaches to the classification of traces, this offers promise for rewarding future development

    Updated T2K measurements of muon neutrino and antineutrino disappearance using 3.6 ×\times 1021^{21} protons on target

    No full text
    International audienceMuon neutrino and antineutrino disappearance probabilities are identical in the standard three-flavor neutrino oscillation framework, but CPT violation and non-standard interactions can violate this symmetry. In this work we report the measurements of sin⁡2ξ23\sin^{2} \theta_{23} and Δm322\Delta m_{32}^2 independently for neutrinos and antineutrinos. The aforementioned symmetry violation would manifest as an inconsistency in the neutrino and antineutrino oscillation parameters. The analysis discussed here uses a total of 1.97×\times1021^{21} and 1.63×\times1021^{21} protons on target taken with a neutrino and antineutrino beam respectively, and benefits from improved flux and cross-section models, new near detector samples and more than double the data reducing the overall uncertainty of the result. No significant deviation is observed, consistent with the standard neutrino oscillation picture

    Cognitive functional therapy with or without movement sensor biofeedback versus usual care for chronic, disabling low back pain (RESTORE): a randomised, controlled, three-arm, parallel group, phase 3, clinical trial

    Get PDF
    BACKGROUND: Low back pain is the leading cause of years lived with disability globally, but most interventions have only short-lasting, small to moderate effects. Cognitive functional therapy (CFT) is an individualised approach that targets unhelpful pain-related cognitions, emotions, and behaviours that contribute to pain and disability. Movement sensor biofeedback might enhance treatment effects. We aimed to compare the effectiveness and economic efficiency of CFT, delivered with or without movement sensor biofeedback, with usual care for patients with chronic, disabling low back pain. METHODS: RESTORE was a randomised, controlled, three-arm, parallel group, phase 3 trial, done in 20 primary care physiotherapy clinics in Australia. We recruited adults (aged ≄18 years) with low back pain lasting more than 3 months with at least moderate pain-related physical activity limitation. Exclusion criteria were serious spinal pathology (eg, fracture, infection, or cancer), any medical condition that prevented being physically active, being pregnant or having given birth within the previous 3 months, inadequate English literacy for the study's questionnaires and instructions, a skin allergy to hypoallergenic tape adhesives, surgery scheduled within 3 months, or an unwillingness to travel to trial sites. Participants were randomly assigned (1:1:1) via a centralised adaptive schedule to usual care, CFT only, or CFT plus biofeedback. The primary clinical outcome was activity limitation at 13 weeks, self-reported by participants using the 24-point Roland Morris Disability Questionnaire. The primary economic outcome was quality-adjusted life-years (QALYs). Participants in both interventions received up to seven treatment sessions over 12 weeks plus a booster session at 26 weeks. Physiotherapists and patients were not masked. This trial is registered with the Australian New Zealand Clinical Trials Registry, ACTRN12618001396213. FINDINGS: Between Oct 23, 2018 and Aug 3, 2020, we assessed 1011 patients for eligibility. After excluding 519 (51·3%) ineligible patients, we randomly assigned 492 (48·7%) participants; 164 (33%) to CFT only, 163 (33%) to CFT plus biofeedback, and 165 (34%) to usual care. Both interventions were more effective than usual care (CFT only mean difference -4·6 [95% CI -5·9 to -3·4] and CFT plus biofeedback mean difference -4·6 [-5·8 to -3·3]) for activity limitation at 13 weeks (primary endpoint). Effect sizes were similar at 52 weeks. Both interventions were also more effective than usual care for QALYs, and much less costly in terms of societal costs (direct and indirect costs and productivity losses; -AU$5276 [-10 529 to -24) and -8211 (-12 923 to -3500). INTERPRETATION: CFT can produce large and sustained improvements for people with chronic disabling low back pain at considerably lower societal cost than that of usual care. FUNDING: Australian National Health and Medical Research Council and Curtin University

    Management of patients with advanced prostate cancer—metastatic and/or castration-resistant prostate cancer: report of the Advanced Prostate Cancer Consensus Conference (APCCC) 2022

    Get PDF
    © 2023 The Authors. Published by Elsevier. This is an open access article available under a Creative Commons licence. The published version can be accessed at the following link on the publisher’s website: https://doi.org/10.1016/j.ejca.2023.02.018Background: Innovations in imaging and molecular characterisation together with novel treatment options have improved outcomes in advanced prostate cancer. However, we still lack high-level evidence in many areas relevant to making management decisions in daily clinical practise. The 2022 Advanced Prostate Cancer Consensus Conference (APCCC 2022) addressed some questions in these areas to supplement guidelines that mostly are based on level 1 evidence. Objective: To present the voting results of the APCCC 2022. Design, setting, and participants: The experts voted on controversial questions where high-level evidence is mostly lacking: locally advanced prostate cancer; biochemical recurrence after local treatment; metastatic hormone-sensitive, non-metastatic, and metastatic castration-resistant prostate cancer; oligometastatic prostate cancer; and managing side effects of hormonal therapy. A panel of 105 international prostate cancer experts voted on the consensus questions. Outcome measurements and statistical analysis: The panel voted on 198 pre-defined questions, which were developed by 117 voting and non-voting panel members prior to the conference following a modified Delphi process. A total of 116 questions on metastatic and/or castration-resistant prostate cancer are discussed in this manuscript. In 2022, the voting was done by a web-based survey because of COVID-19 restrictions. Results and limitations: The voting reflects the expert opinion of these panellists and did not incorporate a standard literature review or formal meta-analysis. The answer options for the consensus questions received varying degrees of support from panellists, as reflected in this article and the detailed voting results are reported in the supplementary material. We report here on topics in metastatic, hormone-sensitive prostate cancer (mHSPC), non-metastatic, castration-resistant prostate cancer (nmCRPC), metastatic castration-resistant prostate cancer (mCRPC), and oligometastatic and oligoprogressive prostate cancer. Conclusions: These voting results in four specific areas from a panel of experts in advanced prostate cancer can help clinicians and patients navigate controversial areas of management for which high-level evidence is scant or conflicting and can help research funders and policy makers identify information gaps and consider what areas to explore further. However, diagnostic and treatment decisions always have to be individualised based on patient characteristics, including the extent and location of disease, prior treatment(s), co-morbidities, patient preferences, and treatment recommendations and should also incorporate current and emerging clinical evidence and logistic and economic factors. Enrolment in clinical trials is strongly encouraged. Importantly, APCCC 2022 once again identified important gaps where there is non-consensus and that merit evaluation in specifically designed trials. Patient summary: The Advanced Prostate Cancer Consensus Conference (APCCC) provides a forum to discuss and debate current diagnostic and treatment options for patients with advanced prostate cancer. The conference aims to share the knowledge of international experts in prostate cancer with healthcare providers worldwide. At each APCCC, an expert panel votes on pre-defined questions that target the most clinically relevant areas of advanced prostate cancer treatment for which there are gaps in knowledge. The results of the voting provide a practical guide to help clinicians discuss therapeutic options with patients and their relatives as part of shared and multidisciplinary decision-making. This report focuses on the advanced setting, covering metastatic hormone-sensitive prostate cancer and both non-metastatic and metastatic castration-resistant prostate cancer. Twitter summary: Report of the results of APCCC 2022 for the following topics: mHSPC, nmCRPC, mCRPC, and oligometastatic prostate cancer. Take-home message: At APCCC 2022, clinically important questions in the management of advanced prostate cancer management were identified and discussed, and experts voted on pre-defined consensus questions. The report of the results for metastatic and/or castration-resistant prostate cancer is summarised here.Published versio
    • 

    corecore