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To identify potential participants for clinical trials, electronic health records (EHRs) are searched at potential sites. As an alternative, we investigated using medical devices used for real-time diagnostic decisions for trial enrollment.
To project cohorts for a trial in acute coronary syndromes (ACS), we used electrocardiograph-based algorithms that identify ACS or ST elevation myocardial infarction (STEMI) that prompt clinicians to offer patients trial enrollment. We searched six hospitals’ electrocardiograph systems for electrocardiograms (ECGs) meeting the planned trial’s enrollment criterion: ECGs with STEMI or > 75% probability of ACS by the acute cardiac ischemia time-insensitive predictive instrument (ACI-TIPI). We revised the ACI-TIPI regression to require only data directly from the electrocardiograph, the e-ACI-TIPI using the same data used for the original ACI-TIPI (development set n = 3,453; test set n = 2,315). We also tested both on data from emergency department electrocardiographs from across the US (n = 8,556). We then used ACI-TIPI and e-ACI-TIPI to identify potential cohorts for the ACS trial and compared performance to cohorts from EHR data at the hospitals.
Receiver-operating characteristic (ROC) curve areas on the test set were excellent, 0.89 for ACI-TIPI and 0.84 for the e-ACI-TIPI, as was calibration. On the national electrocardiographic database, ROC areas were 0.78 and 0.69, respectively, and with very good calibration. When tested for detection of patients with > 75% ACS probability, both electrocardiograph-based methods identified eligible patients well, and better than did EHRs.
Using data from medical devices such as electrocardiographs may provide accurate projections of available cohorts for clinical trials.
To assess general medical residents’ familiarity with antibiograms using a self-administered survey
Cross-sectional, single-center survey
Residents in internal medicine, family medicine, and pediatrics at an academic medical center
Participants were administered an anonymous survey at our institution during regularly scheduled educational conferences between January and May 2012. Questions collected data regarding demographics, professional training; further open-ended questions assessed knowledge and use of antibiograms regarding possible pathogens, antibiotic regimens, and prescribing resources for 2 clinical vignettes; a series of directed, closed-ended questions followed. Bivariate analyses to compare responses between residency programs were performed.
Of 122 surveys distributed, 106 residents (87%) responded; internal medicine residents accounted for 69% of responses. More than 20% of residents could not accurately identify pathogens to target with empiric therapy or select therapy with an appropriate spectrum of activity in response to the clinical vignettes; correct identification of potential pathogens was not associated with selecting appropriate therapy. Only 12% of respondents identified antibiograms as a resource when prescribing empiric antibiotic therapy for scenarios in the vignettes, with most selecting the UpToDate online clinical decision support resource or The Sanford Guide. When directly questioned, 89% reported awareness of institutional antibiograms, but only 70% felt comfortable using them and only 44% knew how to access them.
When selecting empiric antibiotics, many residents are not comfortable using antibiograms as part of treatment decisions. Efforts to improve antibiotic use may benefit from residents being given additional education on both infectious diseases pharmacotherapy and antibiogram utilization.
Adélie penguins (Pygoscelis adeliae) are responding to ocean–climate variability throughout the marine ecosystem of the western Antarctic Peninsula (WAP) where some breeding colonies have declined by 80%. Nuclear and mitochondrial DNA (mtDNA) markers were used to understand historical population genetic structure and gene flow given relatively recent and continuing reductions in sea ice habitats and changes in numbers of breeding adults at colonies throughout the WAP. Genetic diversity, spatial genetic structure, genetic signatures of fluctuations in population demography and gene flow were assessed in four regional Adélie penguin colonies. The analyses indicated little genetic structure overall based on bi-parentally inherited microsatellite markers (FST =-0.006–0.004). No significant variance was observed in overall haplotype frequency (mtDNA ΦST =0.017; P=0.112). Some comparisons with Charcot Island were significant, suggestive of female-biased philopatry. Estimates of gene flow based on a two-population coalescent model were asymmetrical from the species’ regional core to its northern range. Breeding Adélie penguins of the WAP are a panmictic population and hold adequate genetic diversity and dispersal capacity to be resilient to environmental change.
A comparison has been mager between ice velocities that were measured by the radio-echo technique and by a survey method on the Devon Island ice cap, Arctic Canada (lat. 75° 23' N., long. 82° 23'W.). Results were 2.58±0.11 ma1 by radar and 2.17±0.20 m a–1 by survey. The discrepancy between the two measurements is within the limits of statistical significance, and the methods are consigerred to give comparable results.
Background: The Supreme Court of Canada (SCC) recently rendered a decision striking down the Criminal Code absolute prohibition on providing assisted dying. End of life decisions are commonly encountered by neurosurgeons due to the nature of their practice. Neurosurgeons will be faced with patients requesting PAD in the near future. Methods: The recent SCC ruling heralds a change that will radically alter a most basic tenet that has historically guided physicians and surgeons. A subcommittee of the Canadian Neurosurgical Society (CNSS) was formed to generate a position statement to reflect the interests of both neurosurgeons and their patients. Results: Fundamental issues regarding the implementation of PAD identified include:
Clarity of legislation
The creation of an independent, third party referral service
Effective safeguards and oversight of the entire process
-The right to “conscientious objection” on the part of hysicians who do not wish to be involved in PAD
Conclusions: The CNSS urges clarity in legislation regarding PAD and strict oversight in its implementation to reduce potential harm. We also support the creation of an independent, third party referral service which would serve to respect the conscience of those health care providers who do not wish to actively participate in PAD.
This study examined whether a family-based preventive intervention for inner-city children entering the first grade could alter the developmental course of attention-deficit/hyperactivity disorder (ADHD) symptoms. Participants were 424 families randomly selected and randomly assigned to a control condition (n = 192) or Schools and Families Educating Children (SAFE) Children (n = 232). SAFE Children combined family-focused prevention with academic tutoring to address multiple developmental–ecological needs. A booster intervention provided in the 4th grade to randomly assigned children in the initial intervention (n =101) evaluated the potential of increasing preventive effects. Follow-up occurred over 5 years with parents and teachers reporting on attention problems. Growth mixture models identified multiple developmental trajectories of ADHD symptoms. The initial phase of intervention placed children on more positive developmental trajectories for impulsivity and hyperactivity, demonstrating the potential for ADHD prevention in at-risk youth, but the SAFE Children booster had no additional effect on trajectory or change in ADHD indicators.
GaAs/AlGaAs N-p-n heterojunction bipolar transistor (GaAs HBT) device and integrated circuit technology which offers key advantages over advanced silicon bipolar and III-V compound field-effect transistors is maturing towards system insertion. The TRW device and IC fabrication process, basic HBT dc and RF performance, examples of device and IC applications, and technology qualification work are presented and serves as a basis for discussing overall technology issues and impact. A relaxed 3-μm emitter-up, self-aligned base ohmic metal (SABM) HBT process and simplified molecularbeam epitaxial profiles are used for near-term producibility. The HBTs have simultaneous fT, fmax≈20–40 GHz and dc current gain ß≈50–100 at collector current density JC=3 kA/cm2 and Early voltage VA≈200–300 with capability for MSI-LSI integration levels. Versatile dc-20 GHz analog, 3–6 Gb/s digital, and 2–3 Gs/s A/D conversion functions are demonstrated with a common 3-μm SABM HBT process which facilitates single-chip multifunctional capability. Key improvements are realized over Si bipolar and GaAs-related FET (e.g. MESFET and HEMT) approaches in operational frequency, gain-bandwidth product, harmonic distortion, 1/f noise, power consumption, and size reduction.
New approaches to both second-order and third-order nonlinear optical materials are presented. A series of organometallic and organic salts, in which the cation has been designed to have a large molecular hyperpolarizability, has been prepared and the SHG efficiencies were measured. Partially substituted derivatives of polyacetylene are synthesized via the ring-opening metathesis polymerization (ROMP) of cyclooctatetraene (COT) and its derivatives. Certain poly-COT derivatives afford soluble, highly conjugated polyacetylenes. These materials exhibit large third-order optical nonlinearities and low scattering losses.
Sputter deposited MnSb thin films were annealed utilizing KrF excimer laser pulses (16ns), and the resulting structural and magnetic changes investigated. These changes are compared to those observed when the samples are subjected to isothermal and rapid thermal annealing treatments. Isothermal and rapid thermal annealing induce significant lateral grain growth, whereas the laser treatment produces vertical grain size refinement with no appreciable lateral growth. Annealing is shown to increase the hexagonal c-axis, reaching an expansion value of 7% for the laser annealed samples. This c-axis expansion has a strong influence on the magnetic properties of the thin films. Mechanisms for the c-axis expansion are discussed.