1,359 research outputs found

    Space Climate Manifestation in Earth Prices - from Medieval England Up to Modern Usa

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    In this study we continue to search for possible manifestations of space weather influence on prices of agricultural products and consumables. We note that the connection between solar activity and prices is based on the causal chain that includes several nonlinear transition elements. These non-linear elements are characterized by threshold sensitivity to external parameters and lead to very inhomogeneous local sensitivity of the price to space weather conditions. It is noted that "soft type" models are the most adequate for description of this class of connections. Two main observational effects suitable for testing causal connections of this type of sensitivity are considered: burst-like price reactions on changes in solar activity and price asymmetry for selected phases of the sunspot cycle. The connection, discovered earlier for wheat prices of Medieval England, is examined in this work on the basis of another 700-year data set of consumable prices in England. Using the same technique as in the previous part of our work (Pistilnik and Yom Din 2004) we show that statistical parameters of the interval distributions for price bursts of consumables basket and for sunspot minimum states are similar one to another, like it was reported earlier for wheat price bursts. Possible sources of these consistencies between three different multiyear samples are discussed. For search of possible manifestations of the "space weather - wheat market" connection in modern time, we analyze dynamics of wheat prices in the USA in the twentieth century. We show that the wheat prices revealed a maximum/minimum price asymmetry consistent with the phases of the sunspot cycle. We discuss possible explanations of this observed asymmetry, unexpected under conditions of globalization of the modern wheat market.Comment: First International Symposium on Space Climate: Direct and Indirect Observations of Long-Term Solar Activity, 20-23 June 2004, Oulu, Finlan

    CP^{N-1} models and the Quantized 2D Black Holes

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    We have examined the coupled system of the dilaton gravity and the CPN1CP^{N-1} theory known as a model of the confinement of massive scalar quarks. After the quantization of the system, we could see the quantum effect of the gravitation on the coupling constant of CPN1CP^{N-1} model and how the coupling constant of dynamically induced gauge field changes near the black hole configuration.Comment: 12 pages, Late

    Bayesian Inference in Processing Experimental Data: Principles and Basic Applications

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    This report introduces general ideas and some basic methods of the Bayesian probability theory applied to physics measurements. Our aim is to make the reader familiar, through examples rather than rigorous formalism, with concepts such as: model comparison (including the automatic Ockham's Razor filter provided by the Bayesian approach); parametric inference; quantification of the uncertainty about the value of physical quantities, also taking into account systematic effects; role of marginalization; posterior characterization; predictive distributions; hierarchical modelling and hyperparameters; Gaussian approximation of the posterior and recovery of conventional methods, especially maximum likelihood and chi-square fits under well defined conditions; conjugate priors, transformation invariance and maximum entropy motivated priors; Monte Carlo estimates of expectation, including a short introduction to Markov Chain Monte Carlo methods.Comment: 40 pages, 2 figures, invited paper for Reports on Progress in Physic

    Development of Measure Yourself Concerns and Wellbeing for informal caregivers of people with cancer – a multicentred study

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    Purpose: Measure Yourself Concerns and Wellbeing (MYCaW) is a validated person-centred measure of the concerns and wellbeing of people affected by cancer. Research suggests that the concerns of informal caregivers (ICs) are as complex and severely rated as people with cancer, yet MYCaW has only been used to represent cancer patients’ concerns and wellbeing. This paper reports on the development of a new qualitative coding framework for MYCaW to capture the concerns of ICs, to better understand the needs of this group. Methods: This multicentred study involved collection of data from ICs receiving support from two UK cancer support charities (Penny Brohn UK and Cavendish Cancer Care). Qualitative codes were developed through a detailed thematic analysis of ICs’ stated concerns. Results: Thematic analysis of IC questionnaire data identified key themes which were translated into a coding framework with two overarching sections; 1. ‘informal caregiver concerns for self’ and 2. ‘informal caregiver concerns for the person with cancer’. Supercategories with specific accompanying codes were developed for each section. Two further rounds of framework testing across different cohorts allowed for iterative development and refinement of the framework content. Conclusions: This is the first person-centred tool specifically designed for capturing IC’s concerns through their own words. This coding framework will allow for IC data to be analysed using a rigorous and reproducible method, and therefore reported in a standardised way. This may also be of interest to those exploring the needs of ICs of people in other situations

    Can Measures of Habitual Activity Intensity Stratify Primary Sjogren’s Syndrome Participants With Persistent Fatigue? Insights From the Brc Tools Study

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    Objectives: Many individuals with chronic diseases, such as primary Sjogren’s syndrome (PSS), experience debilitating fatigue that substantially impacts their quality of life. Currently, assessments of fatigue rely on patient reported outcomes, which are subjective and prone to recall bias. Wearable devices, however, can provide continuous estimates of human activity and may provide objective evidence of fatigue. This study aims to stratify PSS patients with different fatigue levels using real-world measures of activity. Methods: 97 participants with PSS wore a VitalPatch chest sensor and a wrist-accelerometer (Actigraph GT9X Link) at home for two 7-day continuous periods. Participants reported their fatigue up to 3 times a day. Participants with minimum fatigue scores of 3-10 were categorised as “persistent fatigue” and 0-2 as “non-persistent fatigue”. The time spent in activity types (standing, walking, or sitting) estimated by the VitalPatch and in activity intensities (inactive, light, moderate, and vigorous) estimated from the accelerometer using GGIR of the two groups were tested with Mann-Whitney U. Results: 49 participants were classified as persistently fatigued. The persistent fatigue group spent more time sitting, inactive, and in moderate activity. But the times spent standing, walking, in light, and in vigorous activities were indistinguishable between the groups. However, the p-values were >0.05 for all activity levels for both sensors. Conclusions: The persistently fatigued participants tended to be less active than the non-persistent group, but this separation was not statistically significant. This is consistent with patient experience and previous studies, where patients who are fatigued are not less active, but such activities might require more effort. Therefore, future research should explore more nuanced measures to investigate the relationships between habitual movement and other physiological signals and fatigue in PSS

    International longitudinal registry of patients with atrial fibrillation and treated with rivaroxaban: RIVaroxaban Evaluation in Real life setting (RIVER)

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    Background Real-world data on non-vitamin K oral anticoagulants (NOACs) are essential in determining whether evidence from randomised controlled clinical trials translate into meaningful clinical benefits for patients in everyday practice. RIVER (RIVaroxaban Evaluation in Real life setting) is an ongoing international, prospective registry of patients with newly diagnosed non-valvular atrial fibrillation (NVAF) and at least one investigator-determined risk factor for stroke who received rivaroxaban as an initial treatment for the prevention of thromboembolic stroke. The aim of this paper is to describe the design of the RIVER registry and baseline characteristics of patients with newly diagnosed NVAF who received rivaroxaban as an initial treatment. Methods and results Between January 2014 and June 2017, RIVER investigators recruited 5072 patients at 309 centres in 17 countries. The aim was to enroll consecutive patients at sites where rivaroxaban was already routinely prescribed for stroke prevention. Each patient is being followed up prospectively for a minimum of 2-years. The registry will capture data on the rate and nature of all thromboembolic events (stroke / systemic embolism), bleeding complications, all-cause mortality and other major cardiovascular events as they occur. Data quality is assured through a combination of remote electronic monitoring and onsite monitoring (including source data verification in 10% of cases). Patients were mostly enrolled by cardiologists (n = 3776, 74.6%), by internal medicine specialists 14.2% (n = 718) and by primary care/general practice physicians 8.2% (n = 417). The mean (SD) age of the population was 69.5 (11.0) years, 44.3% were women. Mean (SD) CHADS2 score was 1.9 (1.2) and CHA2DS2-VASc scores was 3.2 (1.6). Almost all patients (98.5%) were prescribed with once daily dose of rivaroxaban, most commonly 20 mg (76.5%) and 15 mg (20.0%) as their initial treatment; 17.9% of patients received concomitant antiplatelet therapy. Most patients enrolled in RIVER met the recommended threshold for AC therapy (86.6% for 2012 ESC Guidelines, and 79.8% of patients according to 2016 ESC Guidelines). Conclusions The RIVER prospective registry will expand our knowledge of how rivaroxaban is prescribed in everyday practice and whether evidence from clinical trials can be translated to the broader cross-section of patients in the real world

    Nearfield Summary and Statistical Analysis of the Second AIAA Sonic Boom Prediction Workshop

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    A summary is provided for the Second AIAA Sonic Boom Workshop held 8-9 January 2017 in conjunction with AIAA SciTech 2017. The workshop used three required models of increasing complexity: an axisymmetric body, a wing body, and a complete configuration with flow-through nacelle. An optional complete configuration with propulsion boundary conditions is also provided. These models are designed with similar nearfield signatures to isolate geometry and shock/expansion interaction effects. Eleven international participant groups submitted nearfield signatures with forces, pitching moment, and iterative convergence norms. Statistics and grid convergence of these nearfield signatures are presented. These submissions are propagated to the ground, and noise levels are computed. This allows the grid convergence and the statistical distribution of a noise level to be computed. While progress is documented since the first workshop, improvement to the analysis methods for a possible subsequent workshop are provided. The complete configuration with flow-through nacelle showed the most dramatic improvement between the two workshops. The current workshop cases are more relevant to vehicles with lower loudness and have the potential for lower annoyance than the first workshop cases. The models for this workshop with quieter ground noise levels than the first workshop exposed weaknesses in analysis, particularly in convective discretization

    Why Are Outcomes Different for Registry Patients Enrolled Prospectively and Retrospectively? Insights from the Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF).

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    Background: Retrospective and prospective observational studies are designed to reflect real-world evidence on clinical practice, but can yield conflicting results. The GARFIELD-AF Registry includes both methods of enrolment and allows analysis of differences in patient characteristics and outcomes that may result. Methods and Results: Patients with atrial fibrillation (AF) and ≥1 risk factor for stroke at diagnosis of AF were recruited either retrospectively (n = 5069) or prospectively (n = 5501) from 19 countries and then followed prospectively. The retrospectively enrolled cohort comprised patients with established AF (for a least 6, and up to 24 months before enrolment), who were identified retrospectively (and baseline and partial follow-up data were collected from the emedical records) and then followed prospectively between 0-18 months (such that the total time of follow-up was 24 months; data collection Dec-2009 and Oct-2010). In the prospectively enrolled cohort, patients with newly diagnosed AF (≤6 weeks after diagnosis) were recruited between Mar-2010 and Oct-2011 and were followed for 24 months after enrolment. Differences between the cohorts were observed in clinical characteristics, including type of AF, stroke prevention strategies, and event rates. More patients in the retrospectively identified cohort received vitamin K antagonists (62.1% vs. 53.2%) and fewer received non-vitamin K oral anticoagulants (1.8% vs . 4.2%). All-cause mortality rates per 100 person-years during the prospective follow-up (starting the first study visit up to 1 year) were significantly lower in the retrospective than prospectively identified cohort (3.04 [95% CI 2.51 to 3.67] vs . 4.05 [95% CI 3.53 to 4.63]; p = 0.016). Conclusions: Interpretations of data from registries that aim to evaluate the characteristics and outcomes of patients with AF must take account of differences in registry design and the impact of recall bias and survivorship bias that is incurred with retrospective enrolment. Clinical Trial Registration: - URL: http://www.clinicaltrials.gov . Unique identifier for GARFIELD-AF (NCT01090362)
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