2,547 research outputs found
Accidental feminists? Recent histories of South African women
This article reviews Helen Scanlon's book, "Representation and reality", and Nombonisa Gasa's "Women in South African history", and locates each against the historiography of South African women's histor
Double-heterostructure cavities: from theory to design
We derive a frequency-domain-based approach for radiation (FAR) from
double-heterostructure cavity (DHC) modes. We use this to compute the quality
factors and radiation patterns of DHC modes. The semi-analytic nature of our
method enables us to provide a general relationship between the radiation
pattern of the cavity and its geometry. We use this to provide general designs
for ultrahigh quality factor DHCs with radiation patterns that are engineered
to emit vertically
Model selection in High-Dimensions: A Quadratic-risk based approach
In this article we propose a general class of risk measures which can be used
for data based evaluation of parametric models. The loss function is defined as
generalized quadratic distance between the true density and the proposed model.
These distances are characterized by a simple quadratic form structure that is
adaptable through the choice of a nonnegative definite kernel and a bandwidth
parameter. Using asymptotic results for the quadratic distances we build a
quick-to-compute approximation for the risk function. Its derivation is
analogous to the Akaike Information Criterion (AIC), but unlike AIC, the
quadratic risk is a global comparison tool. The method does not require
resampling, a great advantage when point estimators are expensive to compute.
The method is illustrated using the problem of selecting the number of
components in a mixture model, where it is shown that, by using an appropriate
kernel, the method is computationally straightforward in arbitrarily high data
dimensions. In this same context it is shown that the method has some clear
advantages over AIC and BIC.Comment: Updated with reviewer suggestion
MEIS investigations of surface structure
The early work of the FOM-AMOLF group in Amsterdam clearly demonstrated the potential of medium energy ion scattering (MEIS), typically using 100 keV H+ incident ions, to investigate the structure of surfaces, but most current applications of the method are focussed on near-surface compositional studies of non-crystalline films. However, the key strengths of the MEIS technique, notably the use of blocking curves in double-alignment experiments and absolute yield measurements, are extremely effective in providing detailed near-surface structural information for a wide range of crystalline materials. This potential and the underlying methodology, is illustrated through examples of applications to the study of layer-dependent composition and structure in alloy surfaces, in studies of the surface crystallography of an oxide surface (rutile TiO2(1 1 0)) and in investigations of complex adsorbate-induced reconstruction of metal surfaces, including the pseudo-(1 0 0) reconstruction of Cu(1 1 1) induced by adsorption of atomic N and molecular methylthiolate (CH3S–). In addition to the use of calibrated blocking curves, the use of the detailed spectral shape of the surface peak in the scattered ion energy spectra, as a means of providing single-atomic layer resolution of the surface structure, is also discussed
Impact of robotics-led organisational change on the pharmacy workforce - preliminary findings : report for the pharmacy & prescribing support unit, NHS Greater Glasgow & Clyde
This report looks at the preliminary findings on the impact of robotics-led organisational change on the pharmacy workforc
Employer choice and job quality : workplace innovation, work redesign and employee perceptions of job quality in a complex healthcare setting
This article examines employer choice in relation to job quality (JQ). Acknowledging the important role of market, institutional and technological constraints, we highlight the role of employer agency in shaping JQ by reporting on an employer-led service redesign initiative in hospital pharmacy services in Scotland. This redesign initiative aimed at upskilling employees and redirecting their work effort towards high value added, patient-facing work using robotics implementation. The article provides a critical assessment of the success of the initiative in enhancing JQ and explores a range of factors constraining and shaping employers' job quality choices
Membrane insertion of anthrax protective antigen and cytoplasmic delivery of lethal factor occur at different stages of the endocytic pathway
The protective antigen (PA) of anthrax toxin binds to a cell surface receptor, undergoes heptamerization, and binds the enzymatic subunits, the lethal factor (LF) and the edema factor (EF). The resulting complex is then endocytosed. Via mechanisms that depend on the vacuolar ATPase and require membrane insertion of PA, LF and EF are ultimately delivered to the cytoplasm where their targets reside. Here, we show that membrane insertion of PA already occurs in early endosomes, possibly only in the multivesicular regions, but that subsequent delivery of LF to the cytoplasm occurs preferentially later in the endocytic pathway and relies on the dynamics of internal vesicles of multivesicular late endosomes
Parametric estimation and tests through divergences and duality technique
We introduce estimation and test procedures through divergence optimization
for discrete or continuous parametric models. This approach is based on a new
dual representation for divergences. We treat point estimation and tests for
simple and composite hypotheses, extending maximum likelihood technique. An
other view at the maximum likelihood approach, for estimation and test, is
given. We prove existence and consistency of the proposed estimates. The limit
laws of the estimates and test statistics (including the generalized likelihood
ratio one) are given both under the null and the alternative hypotheses, and
approximation of the power functions is deduced. A new procedure of
construction of confidence regions, when the parameter may be a boundary value
of the parameter space, is proposed. Also, a solution to the irregularity
problem of the generalized likelihood ratio test pertaining to the number of
components in a mixture is given, and a new test is proposed, based on -divergence on signed finite measures and duality technique
Impact of large-scale automation on healthcare staff
New technological advancements are often a driver for change in the redesign of services. More research is needed to better understand the impact of socio-technical dimensions on the implementation of new technological systems in hospital pharmacy. This paper aims to analyse the experiences arising from the large-scale automation of medicines distribution. The introduction of new technology may not only lead to unintended first-order consequences, but can also generate potentially serious adverse feedback loops between the social and technical dimensions. In addition, the longer-term impact of new technology may be quite different for different groups of healthcare staff
Innovation in healthcare systems : a socio-technical perspective
We have investigated the large-scale automation of medicines distribution in NHS Greater Glasgow & Clyde, which is the largest regional health organisation in the UK. The pharmacy service is delivered on 14 hospital sites, involving approximately 530 pharmacy staff and an annual expenditure on medicines of around €138 million.The empirical evidence on the success of technological innovations in healthcare systems is decidedly mixed. There is considerable evidence on both theoretical and empirical grounds that the severity of implementation problems is likely to increase disproportionately with the scale and complexity of a healthcare technology installation. A key finding from the initial stage of our research was that the introduction of new technology in healthcare may not only lead to unintended first-order consequences such as initial staff resistance, but can also generate potentially serious adverse feedback loops between the social and technical dimensions of the new system. A key finding from the second stage of the research is that the longer-term impact of new technology may be quite different for different groups of healthcare staff. New automated systems may free front-stage staff from more routine administrative activities, enabling them to spend more time directly with patients. On the other hand, back-stage staff may well find that their learning opportunities and promotion possibilities are curtailed as a result
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