374 research outputs found
The Generative Programs Framework
Recently there has been significant interest in using causal modelling
techniques to understand the structure of physical theories. However, the
notion of `causation' is limiting - insisting that a physical theory must
involve causal structure already places significant constraints on the form
that theory may take. Thus in this paper, we aim to set out a more general
structural framework. We argue that any quantitative physical theory can be
represented in the form of a generative program, i.e. a list of instructions
showing how to generate the empirical data; the information-processing
structure associated with this program can be represented by a directed acyclic
graph (DAG). We suggest that these graphs can be interpreted as encoding
relations of `ontological priority,' and that ontological priority is a
suitable generalisation of causation which applies even to theories that don't
have a natural causal structure. We discuss some applications of our framework
to philosophical questions about realism, operationalism, free will, locality
and fine-tuning.Comment: 42 pages, 15 figures, 19 pages of supplementary materia
Behavioural activation written self-help to improve mood, wellbeing and quality of life in people with dementia supported by informal carers (PROMOTE): study protocol for a single-arm feasibility study.
Background: Increases in life expectancy have resulted in a global rise in dementia
prevalence. Dementia is associated with poor wellbeing, low quality of life and
increased incidence of mental health difficulties such as, low mood or depression.
However, currently there is limited access to evidence-based psychological
interventions for people with dementia experiencing low mood and poor wellbeing.
Behavioural activation-based self-help, supported by informal carers and guided by
mental health professionals, may represent an effective and acceptable solution.
Methods/design: The present study is a Phase II (feasibility) single-arm trial informed
by the MRC Complex Interventions Research Methods Framework. Up to fifty
dementia participant/informal carer dyads will be recruited from a variety of settings
including primary care, dementia-specific health settings, and community outreach.
People living with dementia will receive behavioural activation based self-help and be
supported by their informal carer who has received training in the skills required to
support the self-help approach. In turn, during the use of the intervention the informal
carer will be guided by mental health professionals to help them work through the
materials and problem solve any difficulties. Consistent with the objectives of feasibility
studies, outcomes relating to recruitment from different settings, employment of
different recruitment methods, attrition, data collection procedures, clinical delivery and
acceptability of the intervention will be examined. Clinical outcomes for people with
dementia (symptoms of depression and quality of life) and informal carers (symptoms
of depression and anxiety, carer burden and quality of life) will be measured pretreatment
and at 3 months post-treatment allocation.
Discussion: This study will examine the feasibility and acceptability of a novel
behavioural activation-based self-help intervention designed to promote wellbeing and
improve low mood in people living with dementia, alongside methodological and
procedural uncertainties associated with research-related procedures. As determined
by pre-specified progression criteria, if research procedures and the new intervention
demonstrate feasibility and acceptability, results will then be used to inform the design
of a pilot randomised controlled trial (RCT) to specifically examine remaining
methodological uncertainties associated with recruitment into a randomised controlled
design.This study is collaboratively funded by Cornwall Foundation Partnership Trust, South West
Peninsula Academic Health Sciences Network and the University of Exeter
Identifying culturally significant areas for marine spatial planning
Despite the growing recognition of their importance, immaterial cultural values associated with the sea still tend to be neglected in marine spatial planning (MSP). This socio-cultural evidence gap is due to inherent difficulties in defining and eliciting cultural values, but also to difficulties in linking cultural values to specific places, thus enabling an area-based approach to management. This paper addresses three aspects that are important for including marine cultural values in MSP: Defining cultural values, identifying places of cultural importance, and establishing the relative significance of places of cultural importance. We argue that common classification schemes such as cultural ecosystem services can be a helpful starting point for identifying cultural values, but only go so far in capturing communities' cultural connections with the sea. A method is proposed for structuring a community-based narrative on cultural values and “spatialising” them for MSP purposes, using five criteria that can lead to the definition of “culturally significant areas”. A baseline of culturally significant areas is suggested as an aid to planners to pinpoint places where cultural connections to the sea are particularly strong. Throughout, we emphasise the need for participative processes
Prevalence of Cardiovascular Disease in Patients With Potentially Curable Malignancies: A National Registry Dataset Analysis
Background: Although a common challenge for patients and clinicians, there is little population-level evidence on the prevalence of cardiovascular disease (CVD) in individuals diagnosed with potentially curable cancer.
Objectives: We investigated CVD rates in patients with common potentially curable malignancies and evaluated the associations between patient and disease characteristics and CVD prevalence.
Methods: The study included cancer registry patients diagnosed in England with stage I to III breast cancer, stage I to III colon or rectal cancer, stage I to III prostate cancer, stage I to IIIA non-small-cell lung cancer, stage I to IV diffuse large B-cell lymphoma, and stage I to IV Hodgkin lymphoma from 2013 to 2018. Linked hospital records and national CVD databases were used to identify CVD. The rates of CVD were investigated according to tumor type, and associations between patient and disease characteristics and CVD prevalence were determined.
Results: Among the 634,240 patients included, 102,834 (16.2%) had prior CVD. Men, older patients, and those living in deprived areas had higher CVD rates. Prevalence was highest for non-small-cell lung cancer (36.1%) and lowest for breast cancer (7.7%). After adjustment for age, sex, the income domain of the Index of Multiple Deprivation, and Charlson comorbidity index, CVD remained higher in other tumor types compared to breast cancer patients.
Conclusions: There is a significant overlap between cancer and CVD burden. It is essential to consider CVD when evaluating national and international treatment patterns and cancer outcomes
Prevalence of Cardiovascular Disease in Patients With Potentially Curable Malignancies: A National Registry Dataset Analysis.
BACKGROUND: Although a common challenge for patients and clinicians, there is little population-level evidence on the prevalence of cardiovascular disease (CVD) in individuals diagnosed with potentially curable cancer. OBJECTIVES: We investigated CVD rates in patients with common potentially curable malignancies and evaluated the associations between patient and disease characteristics and CVD prevalence. METHODS: The study included cancer registry patients diagnosed in England with stage I to III breast cancer, stage I to III colon or rectal cancer, stage I to III prostate cancer, stage I to IIIA non-small-cell lung cancer, stage I to IV diffuse large B-cell lymphoma, and stage I to IV Hodgkin lymphoma from 2013 to 2018. Linked hospital records and national CVD databases were used to identify CVD. The rates of CVD were investigated according to tumor type, and associations between patient and disease characteristics and CVD prevalence were determined. RESULTS: Among the 634,240 patients included, 102,834 (16.2%) had prior CVD. Men, older patients, and those living in deprived areas had higher CVD rates. Prevalence was highest for non-small-cell lung cancer (36.1%) and lowest for breast cancer (7.7%). After adjustment for age, sex, the income domain of the Index of Multiple Deprivation, and Charlson comorbidity index, CVD remained higher in other tumor types compared to breast cancer patients. CONCLUSIONS: There is a significant overlap between cancer and CVD burden. It is essential to consider CVD when evaluating national and international treatment patterns and cancer outcomes
Equivalence problem for the orthogonal webs on the sphere
We solve the equivalence problem for the orthogonally separable webs on the
three-sphere under the action of the isometry group. This continues a classical
project initiated by Olevsky in which he solved the corresponding canonical
forms problem. The solution to the equivalence problem together with the
results by Olevsky forms a complete solution to the problem of orthogonal
separation of variables to the Hamilton-Jacobi equation defined on the
three-sphere via orthogonal separation of variables. It is based on invariant
properties of the characteristic Killing two-tensors in addition to properties
of the corresponding algebraic curvature tensor and the associated Ricci
tensor. The result is illustrated by a non-trivial application to a natural
Hamiltonian defined on the three-sphere.Comment: 32 page
Management and outcomes of myocardial infarction in people with impaired kidney function in England
Background: Acute myocardial infarction (AMI) causes significant mortality and morbidity in people with impaired kidney function. Previous observational research has demonstrated reduced use of invasive management strategies and inferior outcomes in this population. Studies from the USA have suggested that disparities in care have reduced over time. It is unclear whether these findings extend to Europe and the UK. Methods: Linked data from four national healthcare datasets were used to investigate management and outcomes of AMI by estimated glomerular filtration rate (eGFR) category in England. Multivariable logistic and Cox regression models compared management strategies and outcomes by eGFR category among people with kidney impairment hospitalised for AMI between 2015–2017. Results: In a cohort of 5 835 people, we found reduced odds of invasive management in people with eGFR < 60mls/min/1.73m2 compared with people with eGFR ≥ 60 when hospitalised for non-ST segment elevation MI (NSTEMI). The association between eGFR and odds of invasive management for ST-elevation MI (STEMI) varied depending on the availability of percutaneous coronary intervention. A graded association between mortality and eGFR category was demonstrated both in-hospital and after discharge for all people. Conclusions: In England, patients with reduced eGFR are less likely to receive invasive management compared to those with preserved eGFR. Disparities in care may however be decreasing over time, with the least difference seen in patients with STEMI managed via the primary percutaneous coronary intervention pathway. Reduced eGFR continues to be associated with worse outcomes after AMI
Solitons of the Resonant Nonlinear Schrodinger Equation with Nontrivial Boundary Conditions and Hirota Bilinear Method
Physically relevant soliton solutions of the resonant nonlinear Schrodinger
(RNLS) equation with nontrivial boundary conditions, recently proposed for
description of uniaxial waves in a cold collisionless plasma, are considered in
the Hirota bilinear approach. By the Madelung representation, the model is
transformed to the reaction-diffusion analog of the NLS equation for which the
bilinear representation, soliton solutions and their mutual interactions are
studied.Comment: 15 pages, 1 figure, talk presented in Workshop `Nonlinear Physics IV:
Theory and Experiment`, 22-30 June 2006, Gallipoli, Ital
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