107 research outputs found

    Preliminary Measurements of the Motion of Arcjet Current Channel Using Inductive Magnetic Probes

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    This paper covers the design and first measurements of non-perturbative, external inductive magnetic diagnostics for arcjet constrictors which can measure the motion of the arc current channel. These measurements of arc motion are motivated by previous simulations using the ARC Heater Simulator (ARCHeS), which predicted unsteady arc motion due to the magnetic kink instability. Measurements of the kink instability are relevant to characterizing motion of the enthalpy profile of the arcjet, the arcjet operational stability, and electrode damage due to associated arc detachment events. These first measurements indicate 4 mm oscillations at 0.5-2 kHz of the current profile

    Federated causal inference based on real-world observational data sources:Application to a SARS-CoV-2 vaccine effectiveness assessment

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    Introduction Causal inference helps researchers and policy-makers to evaluate public health interventions. When comparing interventions or public health programs by leveraging observational sensitive individual-level data from populations crossing jurisdictional borders, a federated approach (as opposed to a pooling data approach) can be used. Approaching causal inference by re-using routinely collected observational data across different regions in a federated manner, is challenging and guidance is currently lacking. With the aim of filling this gap and allowing a rapid response in the case of a next pandemic, a methodological framework to develop studies attempting causal inference using federated cross-national sensitive observational data, is described and showcased within the European BeYond-COVID&nbsp;project. Methods A framework for approaching federated causal inference by re-using routinely collected observational data across different regions, based on principles of legal, organizational, semantic and technical interoperability, is proposed. The framework includes step-by-step guidance, from defining a research question, to establishing a causal model, identifying and specifying data requirements in a common data model, generating synthetic data, and developing an interoperable and reproducible analytical pipeline for distributed deployment. The conceptual and instrumental phase of the framework was demonstrated and an analytical pipeline implementing federated causal inference was prototyped using open-source software in preparation for the assessment of real-world effectiveness of SARS-CoV-2 primary vaccination in preventing infection in populations spanning different countries, integrating a data quality assessment, imputation of missing values, matching of exposed to unexposed individuals based on confounders identified in the causal model and a survival analysis within the matched&nbsp;population. Results The conceptual and instrumental phase of the proposed methodological framework was successfully demonstrated within the BY-COVID project. Different Findable, Accessible, Interoperable and Reusable (FAIR) research objects were produced, such as a study protocol, a data management plan, a common data model, a synthetic dataset and an interoperable analytical&nbsp;pipeline. Conclusions The framework provides a systematic approach to address federated cross-national policy-relevant causal research questions based on sensitive population, health and care data in a privacy-preserving and interoperable way. The methodology and derived research objects can be re-used and contribute to pandemic&nbsp;preparedness.</p

    Anti-inflammatory, but not osteoprotective, effect of the TRAF6/CD40 inhibitor 6877002 in rodent models of local and systemic osteolysis

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    NFκB plays a key role in inflammation and skeletal disorders. Previously, we reported that pharmacological inhibition of NFκB at the level of TRAF6 suppressed RANKL, CD40L and IL1β-induced osteoclastogenesis and attenuated cancer-induced bone disease. TNFα is also known to regulate TRAF6/NFκB signalling, however the anti-inflammatory and osteoprotective effects associated with inhibition of the TNFα/TRAF6/NFκB axis have not been investigated. Here, we show that in vitro and ex vivo exposure to the verified small-molecule inhibitor of TRAF6, 6877002 prevented TNFα-induced NFκB activation, osteoclastogenesis and calvarial osteolysis, but it had no effects on TNFα-induced apoptosis or growth inhibition in osteoblasts. Additionally, 6877002 disrupted T-cells support for osteoclast formation and synoviocyte motility, without affecting the viability of osteoblasts in the presence of T-cells derived factors. Using the collagen-induced arthritis model, we show that oral and intraperitoneal administration of 6877002 in mice reduced joint inflammation and arthritis score. Unexpectedly, no difference in trabecular and cortical bone parameters were detected between vehicle and 6877002 treated mice, indicating lack of osteoprotection by 6877002 in the arthritis model described. Using two independent rodent models of osteolysis, we confirmed that 6877002 had no effect on trabecular and cortical bone loss in both osteoporotic rats or RANKL- treated mice. In contrast, the classic anti-osteolytic alendronate offered complete osteoprotection in RANKL- treated mice. In conclusion, TRAF6 inhibitors may be of value in the management of the inflammatory component of bone disorders, but may not offer protection against local or systemic bone loss, unless combined with anti-resorptive therapy such as bisphosphonates

    Long-term outcome of liver transplantation for unresectable liver metastases from neuroendocrine neoplasms: a Belgian retrospective multi-centre study

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    peer reviewedBackground: Liver transplantation (LT) is the only curative treatment for unresectable liver metastases from neuroendocrine neoplasms (NEN-Liver-Mets). While recurrence is frequent after LT, there is limited data available in the literature on the outcome of recurrent patients. Methods: We retrospectively reviewed the medical records of all patients who underwent LT by NEN-Mets at the six LT centres in Belgium from 1986 to 2020. Patient and tumour characteristics, indication for transplantation, overall survival (OS), disease-free survival (DFS), and tumour recurrence and outcomes were analysed. Results: Forty patients underwent a LT for NEN-Liver-Mets in Belgium. Twenty-nine patients were male (74.2%) with a mean age of 41.9 and 47.1 years at the time of NEN diagnosis and LT, respectively. WHO classification was available for 32 patients and changed over time (see table below). OS post-LT at 1-, 5-, and 10-years are: 84,3%, 65,0% and 54,6% respectively, while the overall DFS are: 76.3%, 44.5% and 38.2% in the same intervals. Patients transplanted after 2010 showed better OS at 5-and 10-years (74.8% and 74.8%) when compared with patients transplanted before (60,0% and 49.5%). Twenty patients (50%) presented a NEN recurrence, of this, 14 (70%) were transplanted before 2010 and only 6 (30%) were transplanted afterwards (p=0.03). The median time for recurrence diagnosis was 12.3 months (range: 5.1 to 69.2). The most frequent recurrence treatments were surgical resection, somatostatin analogs, chemotherapy, and sunitinib therapy (8, 6, 6, and 4 patients, respectively). Survival rates were 89.5% and 56.1% at 1- and 5-years after recurrence diagnosis.Conclusions: Patients transplanted for unresectable NEN-Liver metastases had good long-term survival. Although the total recurrence rate is high, it decreased dramatically after 2010, probably due to better patient selection. Furthermore, recurrence treatment should be recommended as it may prolong patient survival

    Is complementary and alternative medicine (CAM) cost-effective? a systematic review

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    BACKGROUND: Out-of-pocket expenditures of over $34 billion per year in the US are an apparent testament to a widely held belief that complementary and alternative medicine (CAM) therapies have benefits that outweigh their costs. However, regardless of public opinion, there is often little more than anecdotal evidence on the health and economic implications of CAM therapies. The objectives of this study are to present an overview of economic evaluation and to expand upon a previous review to examine the current scope and quality of CAM economic evaluations. METHODS: The data sources used were Medline, AMED, Alt-HealthWatch, and the Complementary and Alternative Medicine Citation Index; January 1999 to October 2004. Papers that reported original data on specific CAM therapies from any form of standard economic analysis were included. Full economic evaluations were subjected to two types of quality review. The first was a 35-item checklist for reporting quality, and the second was a set of four criteria for study quality (randomization, prospective collection of economic data, comparison to usual care, and no blinding). RESULTS: A total of 56 economic evaluations (39 full evaluations) of CAM were found covering a range of therapies applied to a variety of conditions. The reporting quality of the full evaluations was poor for certain items, but was comparable to the quality found by systematic reviews of economic evaluations in conventional medicine. Regarding study quality, 14 (36%) studies were found to meet all four criteria. These exemplary studies indicate CAM therapies that may be considered cost-effective compared to usual care for various conditions: acupuncture for migraine, manual therapy for neck pain, spa therapy for Parkinson's, self-administered stress management for cancer patients undergoing chemotherapy, pre- and post-operative oral nutritional supplementation for lower gastrointestinal tract surgery, biofeedback for patients with "functional" disorders (eg, irritable bowel syndrome), and guided imagery, relaxation therapy, and potassium-rich diet for cardiac patients. CONCLUSION: Whereas the number and quality of economic evaluations of CAM have increased in recent years and more CAM therapies have been shown to be of good value, the majority of CAM therapies still remain to be evaluated

    Forest biodiversity, ecosystem functioning and the provision of ecosystem services

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    Forests are critical habitats for biodiversity and they are also essential for the provision of a wide range of ecosystem services that are important to human well-being. There is increasing evidence that biodiversity contributes to forest ecosystem functioning and the provision of ecosystem services. Here we provide a review of forest ecosystem services including biomass production, habitat provisioning services, pollination, seed dispersal, resistance to wind storms, fire regulation and mitigation, pest regulation of native and invading insects, carbon sequestration, and cultural ecosystem services, in relation to forest type, structure and diversity. We also consider relationships between forest biodiversity and multifunctionality, and trade-offs among ecosystem services. We compare the concepts of ecosystem processes, functions and services to clarify their definitions. Our review of published studies indicates a lack of empirical studies that establish quantitative and causal relationships between forest biodiversity and many important ecosystem services. The literature is highly skewed; studies on provisioning of nutrition and energy, and on cultural services, delivered by mixed-species forests are under-represented. Planted forests offer ample opportunity for optimising their composition and diversity because replanting after harvesting is a recurring process. Planting mixed-species forests should be given more consideration as they are likely to provide a wider range of ecosystem services within the forest and for adjacent land uses. This review also serves as the introduction to this special issue of Biodiversity and Conservation on various aspects of forest biodiversity and ecosystem services

    Anticoagulant Treatment of a Thrombosed Giant Portal Vein Aneurysm

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    Teaching point: Anticoagulation is advised in thrombosed portal vein aneurysm (PVA) without portal hypertension
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