109 research outputs found
High Temperature Microwave Dielectric Properties of JSC-1AC Lunar Simulant
Microwave heating has many potential lunar applications including sintering regolith for lunar surface stabilization and heating regolith for various oxygen production reactors. The microwave properties of lunar simulants must be understood so this technology can be applied to lunar operations. Dielectric properties at microwave frequencies for a common lunar simulant, JSC-1AC, were measured up to 1100 C, which is approximately the melting point. The experimentally determined dielectric properties included real and imaginary permittivity (epsilon', epsilon"), loss tangent (tan delta), and half-power depth, the di stance at which a material absorbs 50% of incident microwave energy. Measurements at 2.45 GHz revealed tan delta of JSC-1A increases from 0.02 at 25 C to 0.31 at 110 C. The corresponding half-power depth decreases from a peak of 286 mm at 110 C, to 13 mm at 1100 C. These data indicate that JSC-1AC becomes more absorbing, and thus a better microwave heater as temperature increases. A half-power depth maximum at 100-200 C presents a barrier to direct microwave heating at low temperatures. Microwave heating experiments confirm the sluggish heating effect of weak absorption below 200 C, and increasingly strong absorption above 200 C, leading to rapid heating and melting of JSC-1AC
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Query Health: standards-based, cross-platform population health surveillance
Objective: Understanding population-level health trends is essential to effectively monitor and improve public health. The Office of the National Coordinator for Health Information Technology (ONC) Query Health initiative is a collaboration to develop a national architecture for distributed, population-level health queries across diverse clinical systems with disparate data models. Here we review Query Health activities, including a standards-based methodology, an open-source reference implementation, and three pilot projects. Materials and methods Query Health defined a standards-based approach for distributed population health queries, using an ontology based on the Quality Data Model and Consolidated Clinical Document Architecture, Health Quality Measures Format (HQMF) as the query language, the Query Envelope as the secure transport layer, and the Quality Reporting Document Architecture as the result language. Results: We implemented this approach using Informatics for Integrating Biology and the Bedside (i2b2) and hQuery for data analytics and PopMedNet for access control, secure query distribution, and response. We deployed the reference implementation at three pilot sites: two public health departments (New York City and Massachusetts) and one pilot designed to support Food and Drug Administration post-market safety surveillance activities. The pilots were successful, although improved cross-platform data normalization is needed. Discussions This initiative resulted in a standards-based methodology for population health queries, a reference implementation, and revision of the HQMF standard. It also informed future directions regarding interoperability and data access for ONC's Data Access Framework initiative. Conclusions: Query Health was a test of the learning health system that supplied a functional methodology and reference implementation for distributed population health queries that has been validated at three sites
TCT-749 The Impact of Race and Gender on Procedural Outcomes After Alcohol Septal Ablation for Symptomatic Hypertrophic Obstructive Cardiomyopathy
Digitalitzat per Artypla
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SHRINE: Enabling Nationally Scalable Multi-Site Disease Studies
Results of medical research studies are often contradictory or cannot be reproduced. One reason is that there may not be enough patient subjects available for observation for a long enough time period. Another reason is that patient populations may vary considerably with respect to geographic and demographic boundaries thus limiting how broadly the results apply. Even when similar patient populations are pooled together from multiple locations, differences in medical treatment and record systems can limit which outcome measures can be commonly analyzed. In total, these differences in medical research settings can lead to differing conclusions or can even prevent some studies from starting. We thus sought to create a patient research system that could aggregate as many patient observations as possible from a large number of hospitals in a uniform way. We call this system the âShared Health Research Information Networkâ, with the following properties: (1) reuse electronic health data from everyday clinical care for research purposes, (2) respect patient privacy and hospital autonomy, (3) aggregate patient populations across many hospitals to achieve statistically significant sample sizes that can be validated independently of a single research setting, (4) harmonize the observation facts recorded at each institution such that queries can be made across many hospitals in parallel, (5) scale to regional and national collaborations. The purpose of this report is to provide open source software for multi-site clinical studies and to report on early uses of this application. At this time SHRINE implementations have been used for multi-site studies of autism co-morbidity, juvenile idiopathic arthritis, peripartum cardiomyopathy, colorectal cancer, diabetes, and others. The wide range of study objectives and growing adoption suggest that SHRINE may be applicable beyond the research uses and participating hospitals named in this report
Probabilistic record linkage of de-identified research datasets with discrepancies using diagnosis codes
International audienceWe develop an algorithm for probabilistic linkage of de-identified research datasets at the patient level, when only diagnosis codes with discrepancies and no personal health identifiers such as name or date of birth are available. It relies on Bayesian modelling of binarized diagnosis codes, and provides a posterior probability of matching for each patient pair, while considering all the data at once. Both in our simulation study (using an administrative claims dataset for data generation) and in two real use-cases linking patient electronic health records from a large tertiary care network, our method exhibits good performance and compares favourably to the standard baseline Fellegi-Sunter algorithm. We propose a scalable, fast and efficient open-source implementation in the ludic R package available on CRAN, which also includes the anonymized diagnosis code data from our real use-case. This work suggests it is possible to link de-identified research databases stripped of any personal health identifiers using only diagnosis codes, provided sufficient information is shared between the data sources
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Scalable Collaborative Infrastructure for a Learning Healthcare System (SCILHS): Architecture
We describe the architecture of the Patient Centered Outcomes Research Institute (PCORI) funded Scalable Collaborative Infrastructure for a Learning Healthcare System (SCILHS, http://www.SCILHS.org) clinical data research network, which leverages the $48 billion dollar federal investment in health information technology (IT) to enable a queryable semantic data model across 10 health systems covering more than 8 million patients, plugging universally into the point of care, generating evidence and discovery, and thereby enabling clinician and patient participation in research during the patient encounter. Central to the success of SCILHS is development of innovative âappsâ to improve PCOR research methods and capacitate point of care functions such as consent, enrollment, randomization, and outreach for patient-reported outcomes. SCILHS adapts and extends an existing national research network formed on an advanced IT infrastructure built with open source, free, modular components
Classic and targeted anti-leukaemic agents interfere with the cholesterol biogenesis metagene in acute myeloid leukaemia: Therapeutic implications
Despite significant advances in deciphering the molecular landscape of acute myeloid leukaemia (AML), therapeutic outcomes of this haematological malignancy have only modestly improved over the past decades. Drug resistance and disease recurrence almost invariably occur, highlighting the need for a deeper understanding of these processes. While low O2 compartments, such as bone marrow (BM) niches, are wellârecognized hosts of drugâresistant leukaemic cells, standard in vitro studies are routinely performed under supraâphysiologic (21% O2, ambient air) conditions, which limits clinical translatability. We hereby identify molecular pathways enriched in AML cells that survive acute challenges with classic or targeted therapeutic agents. Experiments took into account variations in O2 tension encountered by leukaemic cells in clinical settings. Integrated RNA and protein profiles revealed that lipid biosynthesis, and particularly the cholesterol biogenesis branch, is a particularly therapyâinduced vulnerability in AML cells under low O2 states. We also demonstrate that the impact of the cytotoxic agent cytarabine is selectively enhanced by a highâpotency statin. The cholesterol biosynthesis programme is amenable to additional translational opportunities within the expanding AML therapeutic landscape. Our findings support the further investigation of higherâpotency statin (eg rosuvastatin)âbased combination therapies to enhance targeting residual AML cells that reside in low O2 environments
The Effects of Stress at Work and at Home on Inflammation and Endothelial Dysfunction
This study examined whether stress at work and at home may be related to dysregulation of inflammation and endothelial function, two important contributors to the development of cardiovascular disease. In order to explore potential biological mechanisms linking stress with cardiovascular health, we investigated cross-sectional associations between stress at work and at home with an inflammation score (n's range from 406â433) and with two endothelial biomarkers (intercellular and vascular adhesion molecules, sICAM-1 and sVCAM-1; n's range from 205â235) in a cohort of healthy US male health professionals. No associations were found between stress at work or at home and inflammation. Men with high or medium levels of stress at work had significantly higher levels of sVCAM-1 (13% increase) and marginally higher levels of sICAM-1 (9% increase), relative to those reporting low stress at work, independent of health behaviors. Men with high levels of stress at home had marginally higher levels of both sVCAM-1 and sICAM-1 than those with low stress at home. While lack of findings related to inflammation are somewhat surprising, if replicated in future studies, these findings may suggest that endothelial dysfunction is an important biological mechanism linking stress at work with cardiovascular health outcomes in men
The Co-Morbidity Burden of Children and Young Adults with Autism Spectrum Disorders
Objectives: Use electronic health records Autism Spectrum Disorder (ASD) to assess the comorbidity burden of ASD in children and young adults. Study Design: A retrospective prevalence study was performed using a distributed query system across three general hospitals and one pediatric hospital. Over 14,000 individuals under age 35 with ASD were characterized by their co-morbidities and conversely, the prevalence of ASD within these comorbidities was measured. The comorbidity prevalence of the younger (Age<18 years) and older (Age 18â34 years) individuals with ASD was compared. Results: 19.44% of ASD patients had epilepsy as compared to 2.19% in the overall hospital population (95% confidence interval for difference in percentages 13.58â14.69%), 2.43% of ASD with schizophrenia vs. 0.24% in the hospital population (95% CI 1.89â2.39%), inflammatory bowel disease (IBD) 0.83% vs. 0.54% (95% CI 0.13â0.43%), bowel disorders (without IBD) 11.74% vs. 4.5% (95% CI 5.72â6.68%), CNS/cranial anomalies 12.45% vs. 1.19% (95% CI 9.41â10.38%), diabetes mellitus type I (DM1) 0.79% vs. 0.34% (95% CI 0.3â0.6%), muscular dystrophy 0.47% vs 0.05% (95% CI 0.26â0.49%), sleep disorders 1.12% vs. 0.14% (95% CI 0.79â1.14%). Autoimmune disorders (excluding DM1 and IBD) were not significantly different at 0.67% vs. 0.68% (95% CI â0.14-0.13%). Three of the studied comorbidities increased significantly when comparing ages 0â17 vs 18â34 with p<0.001: Schizophrenia (1.43% vs. 8.76%), diabetes mellitus type I (0.67% vs. 2.08%), IBD (0.68% vs. 1.99%) whereas sleeping disorders, bowel disorders (without IBD) and epilepsy did not change significantly. Conclusions: The comorbidities of ASD encompass disease states that are significantly overrepresented in ASD with respect to even the patient populations of tertiary health centers. This burden of comorbidities goes well beyond those routinely managed in developmental medicine centers and requires broad multidisciplinary management that payors and providers will have to plan for
The National COVID Cohort Collaborative (N3C): Rationale, design, infrastructure, and deployment.
OBJECTIVE: Coronavirus disease 2019 (COVID-19) poses societal challenges that require expeditious data and knowledge sharing. Though organizational clinical data are abundant, these are largely inaccessible to outside researchers. Statistical, machine learning, and causal analyses are most successful with large-scale data beyond what is available in any given organization. Here, we introduce the National COVID Cohort Collaborative (N3C), an open science community focused on analyzing patient-level data from many centers.
MATERIALS AND METHODS: The Clinical and Translational Science Award Program and scientific community created N3C to overcome technical, regulatory, policy, and governance barriers to sharing and harmonizing individual-level clinical data. We developed solutions to extract, aggregate, and harmonize data across organizations and data models, and created a secure data enclave to enable efficient, transparent, and reproducible collaborative analytics.
RESULTS: Organized in inclusive workstreams, we created legal agreements and governance for organizations and researchers; data extraction scripts to identify and ingest positive, negative, and possible COVID-19 cases; a data quality assurance and harmonization pipeline to create a single harmonized dataset; population of the secure data enclave with data, machine learning, and statistical analytics tools; dissemination mechanisms; and a synthetic data pilot to democratize data access.
CONCLUSIONS: The N3C has demonstrated that a multisite collaborative learning health network can overcome barriers to rapidly build a scalable infrastructure incorporating multiorganizational clinical data for COVID-19 analytics. We expect this effort to save lives by enabling rapid collaboration among clinicians, researchers, and data scientists to identify treatments and specialized care and thereby reduce the immediate and long-term impacts of COVID-19
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