1,458 research outputs found
Randomisation of Pulse Phases for Unambiguous and Robust Quantum Sensing
We develop theoretically and demonstrate experimentally a universal dynamical
decoupling method for robust quantum sensing with unambiguous signal
identification. Our method uses randomisation of control pulses to suppress
simultaneously two types of errors in the measured spectra that would otherwise
lead to false signal identification. These are spurious responses due to
finite-width pulses, as well as signal distortion caused by pulse
imperfections. For the cases of nanoscale nuclear spin sensing and AC
magnetometry, we benchmark the performance of the protocol with a single
nitrogen vacancy centre in diamond against widely used non-randomised pulse
sequences. Our method is general and can be combined with existing multipulse
quantum sensing sequences to enhance their performance
Generic cardiology drug prices: the potential benefits of the Marc Cuban cost plus drug company model
Introduction: Generic pharmaceuticals account for the majority of the 7.7 billion on the 50 most used generic cardiology drugs by volume in 2020 according to Medicare Part D data. Pharmacy and shipping costs accounted for a substantial portion of expenditures. Per our most conservative estimate, 2.9 billion (38%) savings for 35 of 50 drugs. Discussion: There is enormous potential for cost savings in the US market for generic cardiology drugs. By encouraging increased competition, decreasing administrative costs, and advocating for our patients to compare prices between the MCCPDC and other generic pharmaceutical dispensers, we have the potential to improve access to care and corresponding outcomes for cardiology patients
The Role of Personality In Moving Encounters with Sacred Art
In Roman Catholic and Eastern Orthodox traditions, the material world is understood to contain access points to the transcendent. An icon may move the awestruck believer to emotional engagement and reflection on moral and religious themes. Personality dispositions potentiating the experience of being moved in religious aesthetic contexts have not been thoroughly studied. The present article describes the development and testing of a cross-sectional study into potential belief and personality-related predictors of being moved by sacred art in a lab environment evocative of a holy site. Ninety (90) Christians in Canada and Greece completed personality measures and viewed and rated thematically matched Latin and Byzantine icons. Findings suggest impacts of attachment, imaginativeness, and traditional vs. mystical dispositions in resonance with sacred art, and point to a secure, mystically oriented perceiver. Those who tended towards structured religious lives also presented with a personality profile favouring logical problem-solving. The paradigm applied the social psychological tradition of an evocative lab situation and use of psychometric tests to pressing questions in aesthetics and transpersonal psychology. This study offers a replicable methodology, inviting further empirical inquiry into the experiential texture of being moved and predictive relationships among individual differences at play in moving encounters
Dynamical decoupling based quantum sensing: Floquet analysis and finite-duration-pulse effects
A spin qubit can be protected from a dephasing spin bath using dynamical decoupling (DD). Microwave pi-pulses are repeatedly applied to the spin qubit to invert its state and average out any dephasing. Importantly, this protection fails when the DD pulse spacing is resonant with nuclear spins in the bath and characteristic dips appear in coherence traces forming the basis for nanoscale NMR and MRI. This emerging quantum technology has been demonstrated with the nitrogen vacancy center in diamond. Most DD protocols apply periodic repetitions of a basic pulse unit. This repetition motivates us to model the experiments using Floquet analysis. The characteristic coherence dips are found to be associated with avoided crossings in an underlying Floquet spectrum. The width and shape of these crossings determines the contrast and sharpness of the coherence dips. We derive analytic expressions for the coherence dips in terms of the Floquet quasienergies and Floquet modes. Typically, the DD microwave pulses are modelled as being instantaneous; however, real pulses have some finite duration and it was recently demonstrated that this pulse duration can cause extra dips to appear in coherence traces. We apply Floquet analysis to accurately model the complete system dynamics in the presence of these finite duration pulses and derive analytic expressions for the complete coherence response. We interpret the arrival of extra coherence dips as the opening of previously closed avoided crossings. We use this new understanding to propose protocols to exploit (for increased resolution) or suppress these extra coherence dips. Finally, we model the interplay between finite-duration-pulse effects and microwave detuning errors - an important problem as the detuning error is completely removed by instantaneous pulses so is not captured by most analytic models. We observe drastic effects including the splitting and suppression of the expected DD signal
Efficacy of Revefenacin in treatment of moderate-to-very-severe Chronic Obstructive Pulmonary Disease: a systematic review and meta-analysis
BACKGROUND: Chronic Obstructive Pulmonary Disease (COPD) is a major global health issue responsible for 5% of global deaths each year, and novel treatments are at a premium. Long acting-muscarinic antagonists are a standard treatment for COPD, and the recent approval of Revefenacin, a novel, once-daily, nebulized LAMA, prompts a need for a systematic review and meta-analysis of results. OBJECTIVES: To assess the efficacy of Revefenacin, a novel, once-daily, nebulized LAMA in the treatment of moderate to very severe COPD. DATA SOURCES: MEDLINE (OVID), EMBASE, and CINAHL databases, as well as grey literature sources Clinicaltrials.gov and the International Clinical Trials Registry Portal. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: No age, geographical, contextual or other restrictions were imposed on populations. All human subjects diagnosed with moderate to severe Chronic Obstructive Pulmonary Disease (COPD) were eligible. Intervention: a novel bronchodilator (Revefenacin). Comparator: Placebo. Outcomes: the efficacy of Revefenacin, measured as the endpoint change in trough FEV1 from baseline. Study design: Randomised Controlled Trials (RCTs). Only studies written in English were considered. STUDY APPRAISAL AND SYNTHESIS METHODS: 1571 records were initially screened, with 27 being eligible for full text review. Eventually, 12 articles for 7 trials were included. A random-effects meta-analysis was conducted with the primary outcome of difference in means for change in trough FEV1 from baseline to study endpoint. RESULTS: 1472 patients were analysed, and the overall difference in means was an increase of 119.073 mL in change in trough FEV1 from baseline to study endpoint for the Revefenacin group compared to the placebo. This result was statistically significant, with a 95% confidence interval of 102.254 mL to 135.893 mL. LIMITATIONS: Limitations of the study include possible risk of publication bias and placebo as the only comparator, relatively few trials (7), and a low generalizability of findings due to the specific nature of RCT populations excluding multi-morbid, and other complicated patients. CONCLUSIONS: Revefenacin is an efficacious intervention when compared to placebo in the treatment of moderate to very severe COPD. Further research is needed in order to assess its efficacy compared to current standard of care, through RCTs or network meta-analysis. What is known: - Existing COPD treatments aim to relief symptoms and improve quality of life. - Revefenacin a novel bronchodilator, was approved in 2018 by the US FDA. - Mong-acting muscarinic antagonists are often used in the management of COPD symptoms. What this study adds: - Revefenacin is a novel drug and no systematic review has been conducted on its efficacy. - The meta-analysis utilised a novel method which accounts for the unit-of-analysis error, when comparing multi- arms studies to a single placebo group (technique of exact adjustment
Deep crustal anatexis, magma mixing, and the generation of epizonal plutons in the Southern Rocky Mountains, Colorado
The Never Summer Mountains in north-central Colorado, USA, are cored by two Oligocene, epizonal granitic plutons originally emplaced in the shallow levels of a short-lived (~1 m.y.), small-volume continental magmatic system. The younger Mt. Cumulus stock (28.015 ± 0.012 Ma) is a syenogranite equivalent compositionally to topaz rhyolites. A comparison to the chemical and isotopic composition of crustal xenoliths entrained in nearby Devonian kimberlites demonstrates that the silicic melts parental to the stock were likely derived from anatexis of local Paleoproterozoic, garnet-absent, mafic lower continental crust. In contrast, the older Mt. Richthofen stock is compositionally heterogeneous and ranges from monzodiorite to monzogranite. Major and trace element abundances and Sr, Nd and Pb isotopic ratios in this stock vary regularly with increasing whole rock wt% SiO2. These data suggest that the Mt. Richthofen stock was constructed from mixed mafic and felsic magmas, the former corresponding to lithosphere-derived basaltic magmas similar isotopically to mafic enclaves entrained in the eastern portions of the stock and the latter corresponding to less differentiated versions of the silicic melts parental to the Mt. Cumulus stock. Zircon U–Pb geochronology further reveals that the Mt. Richthofen stock was incrementally emplaced over a time interval from at least 28.975 ± 0.020 to 28.742 ± 0.053 Ma. Magma mixing could have occurred either in situ in the upper crust during basaltic underplating and remelting of an antecedent, incrementally emplaced, silicic intrusive body, or at depth in the lower crust prior to periodic magma ascent and emplacement in the shallow crust. Overall, the two stocks demonstrate that magmatism associated with the Never Summer igneous complex was fundamentally bimodal in composition. Highly silicic anatectic melts of the mafic lower crust and basaltic, mantle-derived magmas were the primary melts in the magma system, with mixing of the two producing intermediate composition magmas such as those from which Mt. Richthofen stock was constructed.National Science Foundation (U.S.) (Grant EAR-0931839
On absolute Galois splitting fields of central simple algebras
A splitting field of a central simple algebra is said to be absolute Galois
if it is Galois over some fixed subfield of the centre of the algebra. The
paper provides an existence theorem for such fields over global fields with
enough roots of unity. As an application, all twisted function fields and all
twisted Laurent series rings over symbol algebras (or p-algebras) over global
fields are crossed products. A closely related statement holds for division
algebras over Henselian valued fields with global residue field.
The existence of absolute Galois splitting fields in central simple algebras
over global fields is equivalent to a suitable generalization of the weak
Grunwald-Wang Theorem, which is proved to hold if enough roots of unity are
present. In general, it does not hold and counter examples have been used in
noncrossed product constructions. This paper shows in particular that a certain
computational difficulty involved in the construction of explicit examples of
noncrossed product twisted Laurent series rings can not be avoided by starting
the construction with a symbol algebra.Comment: 12 pages (A4); to appear in J. Number Theory (2007
Stable and chaotic solutions of the complex Ginzburg-Landau equation with periodic boundary conditions
We study, analytically and numerically, the dynamical behavior of the
solutions of the complex Ginzburg-Landau equation with diffraction but without
diffusion, which governs the spatial evolution of the field in an active
nonlinear laser cavity. Accordingly, the solutions are subject to periodic
boundary conditions. The analysis reveals regions of stable stationary
solutions in the model’s parameter space, and a wide range of oscillatory
and chaotic behaviors. Close to the first bifurcation destabilizing the
spatially uniform solution, a stationary single-humped solution is found in an
asymptotic analytical form, which turns out to be in very good agreement with
the numerical results. Simulations reveal a series of stable stationary
multi-humped solutionsComment: 9 pages, 15 figure
Health Care Professionals’ Views on Using Remote Measurement Technology in Managing Central Nervous System Disorders: Qualitative Interview Study
Background: Remote measurement technologies (RMT) can be used to collect data on a variety of bio-behavioral variables, which may improve the care of patients with central nervous system disorders. Although various studies have explored their potential, prior work has highlighted a knowledge gap in health care professionals’ (HCPs) perceptions of the value of RMT in clinical practice.Objective: This study aims to understand HCPs’ perspectives on using RMT in health care practice for the care of patients with depression, epilepsy, or multiple sclerosis (MS).Methods: Semistructured interviews were conducted with 26 multidisciplinary primary and secondary care HCPs who care for patients with epilepsy, depression, or MS. Interviews were transcribed verbatim and analyzed using thematic analysis.Results: A total of 8 main themes emerged from the analysis: (1) potential clinical value of RMT data; (2) when to use RMT in care pathways; (3) roles of health care staff who may use RMT data; (4) presentation and accessibility of data; (5) obstacles to successful use of RMT; (6) limits to the role of RMT; (7) empowering patients; and (8) considerations around alert-based systems.Conclusions: RMT could add value to the system of care for patients with central nervous system disorders by providing clinicians with graphic summaries of data in the patient record. Barriers of both technical and human nature should be considered when using these technologies, as should the limits to the benefits they can offer
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