300 research outputs found
Joint super-resolution and synthesis of 1 mm isotropic MP-RAGE volumes from clinical MRI exams with scans of different orientation, resolution and contrast
Most existing algorithms for automatic 3D morphometry of human brain MRI scans are designed for data with near-isotropic voxels at approximately 1 mm resolution, and frequently have contrast constraints as well-typically requiring T1-weighted images (e.g., MP-RAGE scans). This limitation prevents the analysis of millions of MRI scans acquired with large inter-slice spacing in clinical settings every year. In turn, the inability to quantitatively analyze these scans hinders the adoption of quantitative neuro imaging in healthcare, and also precludes research studies that could attain huge sample sizes and hence greatly improve our understanding of the human brain. Recent advances in convolutional neural networks (CNNs) are producing outstanding results in super-resolution and contrast synthesis of MRI. However, these approaches are very sensitive to the specific combination of contrast, resolution and orientation of the input images, and thus do not generalize to diverse clinical acquisition protocols - even within sites. In this article, we present SynthSR, a method to train a CNN that receives one or more scans with spaced slices, acquired with different contrast, resolution and orientation, and produces an isotropic scan of canonical contrast (typically a 1 mm MP-RAGE). The presented method does not require any preprocessing, beyond rigid coregistration of the input scans. Crucially, SynthSR trains on synthetic input images generated from 3D segmentations, and can thus be used to train CNNs for any combination of contrasts, resolutions and orientations without high-resolution real images of the input contrasts. We test the images generated with SynthSR in an array of common downstream analyses, and show that they can be reliably used for subcortical segmentation and volumetry, image registration (e.g., for tensor-based morphometry), and, if some image quality requirements are met, even cortical thickness morphometry. The source code is publicly available at https://github.com/BBillot/SynthSR
The transformation of transport policy in Great Britain? 'New Realism' and New Labour's decade of displacement activity
In a 1999 paper, Goodwin announced ‘the transformation of transport policy in Great Britain’. His central point was that consensus was emerging among policy makers and academics based on earlier work including Transport: The New Realism, which rejected previous orthodoxy that the supply of road space could and should be continually expanded to match demand. Instead a combination of investment in public transport, walking and cycling opportunities and – crucially – demand management should form the basis of transport policy to address rising vehicle use and associated increases in congestion and pollution / carbon emissions. This thinking formed the basis of the 1997 Labour government’s ‘sustainable transport’ policy, but after 13 years in power ministers neither transformed policy nor tackled longstanding transport trends. Our main aim in this paper is to revisit the concept of New Realism and re-examine its potential utility as an agent of change in British transport policy. Notwithstanding the outcome of Labour’s approach to transport policy, we find that the central tenets of the New Realism remain robust and that the main barriers to change are related to broader political and governance issues which suppress radical policy innovation
CMB Telescopes and Optical Systems
The cosmic microwave background radiation (CMB) is now firmly established as
a fundamental and essential probe of the geometry, constituents, and birth of
the Universe. The CMB is a potent observable because it can be measured with
precision and accuracy. Just as importantly, theoretical models of the Universe
can predict the characteristics of the CMB to high accuracy, and those
predictions can be directly compared to observations. There are multiple
aspects associated with making a precise measurement. In this review, we focus
on optical components for the instrumentation used to measure the CMB
polarization and temperature anisotropy. We begin with an overview of general
considerations for CMB observations and discuss common concepts used in the
community. We next consider a variety of alternatives available for a designer
of a CMB telescope. Our discussion is guided by the ground and balloon-based
instruments that have been implemented over the years. In the same vein, we
compare the arc-minute resolution Atacama Cosmology Telescope (ACT) and the
South Pole Telescope (SPT). CMB interferometers are presented briefly. We
conclude with a comparison of the four CMB satellites, Relikt, COBE, WMAP, and
Planck, to demonstrate a remarkable evolution in design, sensitivity,
resolution, and complexity over the past thirty years.Comment: To appear in: Planets, Stars and Stellar Systems (PSSS), Volume 1:
Telescopes and Instrumentatio
Peroxisome proliferator-activated receptor-γ protects ERBB2-positive breast cancer cells from palmitate toxicity
Apple Sauce Improves Detection of Esophageal Motor Dysfunction During High-Resolution Manometry Evaluation of Dysphagia
Modeling Musical Structure with Parametric Grammars
International audienceFinding high-level structure in scores is one of the main challenges in music information retrieval. Searching for a formalization enabling variety through fixed musical concepts, we use parametric grammars , an extension of context-free grammars with predicates that take parameters. Parameters are here small patterns of music that will be used with different roles in the piece. We investigate their potential use in defining and discovering the structure of a musical piece, taking example on Bach inventions. A measure of conformance of a score with a given parametric grammar based on the classical notion of edit distance is investigated. Initial analysis of computational properties of the proposed formalism is carried out
The Powerful Student Consumer and the Commodified Academic: A Depiction of the Marketised UK Higher Education System through a Textual Analysis of the ITV Drama Cheat
Through a textual analysis of four episodes comprising the 2019 ITV 1 psychological thriller Cheat, this article explores a fictional representation of the United Kingdom (UK) Higher Education (HE) setting in a television drama. We discuss our analysis in the context of growing marketisation of UK HE, where academics are increasingly viewing students as powerful consumers. We focus on one of the central characters, final-year undergraduate student Rose Vaughan, and the staff with whom she interacts in a fictional HE institution – St. Helen’s College. This article engages with the following themes: ‘The powerful student consumer’ and ‘The commodified academic’. Insight gleaned through the textual analysis of this dramatised depiction of UK HE allows us to attempt to understand how both students and academics might be navigating the neoliberal university and negotiating place and status as (paying) students and (commercial) academics. Although heralded as powerful student-consumers in much literature, our analysis of this television drama shows how students can potentially disrupt the united front often attempted by HE institutions, but ultimately are faced with a ‘the house always wins’1 scenario. Our article offers an important contribution to the psycho-sociological literature into how the television drama depicts that the student experience has been transformed and impacted by HE’s marketisation. This includes a reconsideration of how the television drama portrays what it means to be a student, by exploring how one student is conceptualised, understood, and represented in the psychological thriller
Ascorbate Biosynthesis during Early Fruit Development Is the Main Reason for Its Accumulation in Kiwi
Background: Ascorbic acid (AsA) is a unique antioxidant as well as an enzyme cofactor. Although it has multiple roles in plants, it is unclear how its accumulation is controlled at the expression level, especially in sink tissues. Kiwifruit (Actinidia) is well-known for its high ascorbate content. Our objective was to determine whether AsA accumulates in the fruits primarily through biosynthesis or because it is imported from the foliage. Methodology/Principal Findings: We systematically investigated AsA levels, biosynthetic capacity, and mRNA expression of genes involved in AsA biosynthesis in kiwi (A. deliciosa cv. Qinmei). Recycling and AsA localization were also monitored during fruit development and among different tissue types. Over time, the amount of AsA, with its capacity for higher biosynthesis and lower recycling, peaked at 30 days after anthesis (DAA), and then decreased markedly up to 60 DAA before declining more slowly. Expression of key genes showed similar patterns of change, except for L-galactono-1,4-lactone dehydrogenase and L-galactose-1-phosphate phosphatase (GPP). However, GPP had good correlation with the rate of AsA accumulation. The expression of these genes could be detected in phloem of stem as well as petiole of leaf and fruit. Additionally, fruit petioles had greater ascorbate amounts, although that was the site of lowest expression by most genes. Fruit microtubule tissues also had higher AsA. However, exogenous applications of AsA to those petioles did not lead to its transport into fruits, and distribution of ascorbate was cell-specific in the fruits, with more accumulation occurring in large
A participatory action research approach to strengthening health managers’ capacity at district level in Eastern Uganda
BACKGROUND: Many approaches to improving health managers’ capacity in poor countries, particularly those pursued
by external agencies, employ non-participatory approaches and often seek to circumvent (rather than strengthen)
weak public management structures. This limits opportunities for strengthening local health managers’ capacity,
improving resource utilisation and enhancing service delivery. This study explored the contribution of a participatory
action research approach to strengthening health managers’ capacity in Eastern Uganda.
METHODS: This was a qualitative study that used open-ended key informant interviews, combined with review of
meeting minutes and observations to collect data. Both inductive and deductive thematic analysis was undertaken.
The Competing Values Framework of organisational management functions guided the deductive process of analysis
and the interpretation of the findings. The framework builds on four earlier models of management and regards them
as complementary rather than conflicting, and identifies four managers’ capacities (collaborate, create, compete and
control) by categorising them along two axes, one contrasting flexibility versus control and the other internal versus
external organisational focus.
RESULTS: The findings indicate that the participatory action research approach enhanced health managers’ capacity to
collaborate with others, be creative, attain goals and review progress. The enablers included expanded interaction spaces,
encouragement of flexibility, empowerment of local managers, and the promotion of reflection and accountability. Tension
and conflict across different management functions was apparent; for example, while there was a need to collaborate,
maintaining control over processes was also needed. These tensions meant that managers needed to learn to
simultaneously draw upon and use different capacities as reflected by the Competing Values Framework in
order to maximise their effectiveness.
CONCLUSIONS: Improved health manager capacity is essential if sustained improvements in health outcomes in lowincome
countries are to be attained. The expansion of interaction spaces, encouragement of flexibility, empowerment of
local managers, and the promotion of reflection and accountability were the key means by which participatory action
research strengthened health managers’ capacity. The participatory approach to implementation therefore
created opportunities to strengthen health managers’ capacity
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