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INTRODUCTION: A New Africa’s Media Image?
Africa’s Media Image in the 21st Century is the first book in over twenty years to examine the international media’s coverage of sub-Saharan Africa. It brings together leading researchers and prominent journalists to explore representation of the continent, and the production of that image, especially by international news media. The book highlights factors that have transformed the global media system, changing whose perspectives are told and the forms of media that empower new voices. This introductory chapter by the book editors assesses Africa’s changing media image, examines the new image-makers, and reviews the geopolitics impacting upon that image
Selective recruitment designs for improving observational studies using electronic health records
Large‐scale electronic health records (EHRs) present an opportunity to quickly identify suitable individuals in order to directly invite them to participate in an observational study. EHRs can contain data from millions of individuals, raising the question of how to optimally select a cohort of size n from a larger pool of size N . In this article, we propose a simple selective recruitment protocol that selects a cohort in which covariates of interest tend to have a uniform distribution. We show that selectively recruited cohorts potentially offer greater statistical power and more accurate parameter estimates than randomly selected cohorts. Our protocol can be applied to studies with multiple categorical and continuous covariates. We apply our protocol to a numerically simulated prospective observational study using an EHR database of stable acute coronary disease patients from 82 089 individuals in the U.K. Selective recruitment designs require a smaller sample size, leading to more efficient and cost‐effective studies
Ecological factors controlling biodiversity in the British countryside (ECOFACT). Module 6 - The causes of change in biodiversity. Interim report
Development of a core outcome set for effectiveness studies of breech birth at term (Breech-COS)-an international multi-stakeholder Delphi study: study protocol.
BACKGROUND: Women pregnant with a breech-presenting foetus at term are at increased risk of adverse pregnancy outcomes. The most common intervention used to improve neonatal outcomes is planned delivery by caesarean section. But this is not always possible, and some women prefer to plan a vaginal birth. A number of providers have proposed alternative interventions, such as delivery protocols or specialist teams, but heterogeneity in reported outcomes and their measurements prevents meaningful comparisons. The aim of this paper is to present a protocol for a study to develop a Breech Core Outcome Set (Breech-COS) for studies evaluating the effectiveness of interventions to improve outcomes associated with term breech birth. METHODS: The development of a Breech-COS includes three phases. First, a systematic literature review will be conducted to identify outcomes previously used in effectiveness studies of breech birth at term. A focus group discussion will be conducted with the study's pre-established Patient and Public Involvement (PPI) group, to enable service user perspectives on the results of the literature review to influence the design of the Delphi survey instrument. Second, an international Delphi survey will be conducted to prioritise outcomes for inclusion in the Breech-COS from the point of view of key stakeholders, including perinatal care providers and families who have experienced a term breech pregnancy. Finally, a consensus meeting will be held with stakeholders to ratify the Breech-COS and disseminate findings for application in future effectiveness studies. DISCUSSION: The expectation is that the Breech-COS will always be collected in all clinical trials, audits of practice and other forms of observation research that concern breech birth at term, along with other outcomes of interest. This will facilitate comparing, contrasting and combining studies with the ultimate goal of improved maternal and neonatal outcomes. TRIAL REGISTRATION: Core Outcome Measures in Effectiveness Trials (COMET) #1749
Cassini observations of ion and electron beams at Saturn and their relationship to infrared auroral arcs
We present Cassini Visual and Infrared Mapping Spectrometer observations of infrared auroral emissions from the noon sector of Saturn's ionosphere revealing multiple intense auroral arcs separated by dark regions poleward of the main oval. The arcs are interpreted as the ionospheric signatures of bursts of reconnection occurring at the dayside magnetopause. The auroral arcs were associated with upward field-aligned currents, the magnetic signatures of which were detected by Cassini at high planetary latitudes. Magnetic field and particle observations in the adjacent downward current regions showed upward bursts of 100–360 keV light ions in addition to energetic (hundreds of keV) electrons, which may have been scattered from upward accelerated beams carrying the downward currents. Broadband, upward propagating whistler waves were detected simultaneously with the ion beams. The acceleration of the light ions from low altitudes is attributed to wave-particle interactions in the downward current regions. Energetic (600 keV) oxygen ions were also detected, suggesting the presence of ambient oxygen at altitudes within the acceleration region. These simultaneous in situ and remote observations reveal the highly energetic magnetospheric dynamics driving some of Saturn's unusual auroral features. This is the first in situ identification of transient reconnection events at regions magnetically conjugate to Saturn's magnetopause
Core excitations across the neutron shell gap in ²⁰⁷Tl
The single closed-neutron-shell, one proton-hole nucleus 207Tl was populated in deep-inelastic collisions of a 208Pb beam with a 208Pb target. The yrast and near-yrast level scheme has been established up to high excitation energy, comprising an octupol
Spin-Spin Asymmetries in Large Transverse Momentum Higgs Boson Production
We examine the spin-dependence of standard model Higgs boson production at
large transverse momentum via the processes , , and . The partonic level
spin-spin asymmetries () for these processes are large at SSC/LHC
energies.Comment: 10 pages, 4 figures (not included), LaTeX; PSU/TH/113, MAD/PH/70
Auroral signatures of multiple magnetopause reconnection at Saturn
Auroral observations capture the ionospheric response to dynamics of the whole magnetosphere and may provide evidence of the significance of reconnection at Saturn. Bifurcations of the main dayside auroral emission have been related to reconnection at the magnetopause and their surface is suggested to represent the amount of newly opened flux. This work is the first presentation of multiple brightenings of these auroral features based on Cassini ultraviolet auroral observations. In analogy to the terrestrial case, we propose a process, in which a magnetic flux tube reconnects with other flux tubes at multiple sites. This scenario predicts the observed multiple brightenings, it is consistent with subcorotating auroral features which separate from the main emission, and it suggests north-south auroral asymmetries. We demonstrate that the conditions for multiple magnetopause reconnection can be satisfied at Saturn, like at Earth
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