964 research outputs found
Modelica - A Language for Physical System Modeling, Visualization and Interaction
Modelica is an object-oriented language for modeling of large, complex and heterogeneous physical systems. It is suited for multi-domain modeling, for example for modeling of mechatronics including cars, aircrafts and industrial robots which typically consist of mechanical, electrical and hydraulic subsystems as well as control systems. General equations are used for modeling of the physical phenomena, No particular variable needs to be solved for manually. A Modelica tool will have enough information to do that automatically. The language has been designed to allow tools to generate efficient code automatically. The modeling effort is thus reduced considerably since model components can be reused and tedious and error-prone manual manipulations are not needed. The principles of object-oriented modeling and the details of the Modelica language as well as several examples are presented
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The economics of health
This report presents results from the Economics of Health project funded by the East Midlands Development Agency. The work was undertaken between November 2007 and February 2008. The main aim of the project was to examine the relationship between mental and physical health and employability, labour market participation and economic performance, with specific attention given to the direction of causal relationships
Amplitude and phase evolution of optical fields inside periodic photonic structures
Optical amplitude distributions of light inside periodic photonic structures are visualized with subwavelength resolution. In addition, using a phase-sensitive photon scanning tunneling microscope, we simultaneously map the phase evolution of light. Two different structures, which consist of a ridge wave-guide containing periodic arrays of nanometer scale features, are investigated. We determine the wavelength dependence of the exponential decay rate inside the periodic arrays. Furthermore, various interference patterns are observed, which we interpret as interference between light reflected by the substrate and light inside the waveguide. The phase information obtained reveals scattering phenomena around the periodic array, which gives rise to phase jumps and phase singularities. Locally around the air rods, we observe an unexpected change in effective refractive index, a possible indication for anomalous dispersion resulting from the periodicity of the array
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Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis.
BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London
Treatment of infections caused by multidrug-resistant Gram-negative bacteria:Report of the British Society for Antimicrobial Chemotherapy/Healthcare Infection Society/British Infection Association Joint Working Party
The Working Party makes more than 100 tabulated recommendations in antimicrobial prescribing for the treatment of infections caused by multidrug-resistant (MDR) Gram-negative bacteria (GNB) and suggest further research, and algorithms for hospital and community antimicrobial usage in urinary infection. The international definition of MDR is complex, unsatisfactory and hinders the setting and monitoring of improvement programmes. We give a new definition of multiresistance. The background information on the mechanisms, global spread and UK prevalence of antibiotic prescribing and resistance has been systematically reviewed. The treatment options available in hospitals using intravenous antibiotics and in primary care using oral agents have been reviewed, ending with a consideration of antibiotic stewardship and recommendations. The guidance has been derived from current peer-reviewed publications and expert opinion with open consultation. Methods for systematic review were NICE compliant and in accordance with the SIGN 50 Handbook; critical appraisal was applied using AGREE II. Published guidelines were used as part of the evidence base and to support expert consensus. The guidance includes recommendations for stakeholders (including prescribers) and antibiotic-specific recommendations. The clinical efficacy of different agents is critically reviewed. We found there are very few good-quality comparative randomized clinical trials to support treatment regimens, particularly for licensed older agents. Susceptibility testing of MDR GNB causing infection to guide treatment needs critical enhancements. Meropenem- or imipenem-resistant Enterobacteriaceae should have their carbapenem MICs tested urgently, and any carbapenemase class should be identified: mandatory reporting of these isolates from all anatomical sites and specimens would improve risk assessments. Broth microdilution methods should be adopted for colistin susceptibility testing. Antimicrobial stewardship programmes should be instituted in all care settings, based on resistance rates and audit of compliance with guidelines, but should be augmented by improved surveillance of outcome in Gram-negative bacteraemia, and feedback to prescribers. Local and national surveillance of antibiotic use, resistance and outcomes should be supported and antibiotic prescribing guidelines should be informed by these data. The diagnosis and treatment of both presumptive and confirmed cases of infection by GNB should be improved. This guidance, with infection control to arrest increases in MDR, should be used to improve the outcome of infections with such strains. Anticipated users include medical, scientific, nursing, antimicrobial pharmacy and paramedical staff where they can be adapted for local use
'Choosing shoes': a preliminary study into the challenges facing clinicians in assessing footwear for rheumatoid patients
Background: Footwear has been accepted as a therapeutic intervention for the foot affected
by rheumatoid arthritis (RA). Evidence relating to the objective assessment of footwear in
patients with RA is limited. The aims of this study were to identify current footwear styles,
footwear characteristics, and factors that influence footwear choice experienced by patients
with RA.
Methods: Eighty patients with RA were recruited from rheumatology clinics during the
summer months. Clinical characteristics, global function, and foot impairment and disability
measures were recorded. Current footwear, footwear characteristics and the factors
associated with choice of footwear were identified. Suitability of footwear was recorded using
pre-determined criteria for assessing footwear type, based on a previous study of foot pain.
Results: The patients had longstanding RA with moderate-to severe disability and
impairment. The foot and ankle assessment demonstrated a low-arch profile with both
forefoot and rearfoot structural deformities. Over 50% of shoes worn by patients were opentype
footwear. More than 70% of patients’ footwear was defined as being poor. Poor
footwear characteristics such as heel rigidity and sole hardness were observed. Patients
reported comfort (17%) and fit (14%) as important factors in choosing their own footwear.
Only five percent (5%) of patients wore therapeutic footwear.
Conclusions: The majority of patients with RA wear footwear that has been previously
described as poor. Future work needs to aim to define and justify the specific features of
footwear that may be of benefit to foot health for people with RA
Parallel Mapper
The construction of Mapper has emerged in the last decade as a powerful and
effective topological data analysis tool that approximates and generalizes
other topological summaries, such as the Reeb graph, the contour tree, split,
and joint trees. In this paper, we study the parallel analysis of the
construction of Mapper. We give a provably correct parallel algorithm to
execute Mapper on multiple processors and discuss the performance results that
compare our approach to a reference sequential Mapper implementation. We report
the performance experiments that demonstrate the efficiency of our method
Choice Models in Marketing: Economic Assumptions, Challenges and Trends
Direct utility models of consumer choice are reviewed and developed for understanding consumer preferences. We begin with a review of statistical models of choice, posing a series of modeling challenges that are resolved by considering economic foundations based on con-strained utility maximization. Direct utility models differ from other choice models by directly modeling the consumer utility function used to derive the likelihood of the data through Kuhn-Tucker con-ditions. Recent advances in Bayesian estimation make the estimation of these models computationally feasible, offering advantages in model interpretation over models based on indirect utility, and descriptive models that tend to be highly parameterized. Future trends are dis-cussed in terms of the antecedents and enhancements of utility function specification.
Critical factors for liposome-incorporated tumour-associated antigens to induce protective tumour immunity to SL2 lymphoma cells in mice
Physical
and
immunogenic
properties
of
re-
constituted
membranes
designed
for
the
presentation
of
tumour-associated
antigens
(TAA)
to
the
immune
system
are
described.
Proteins
and
lipids
of
crude
membranes
of
SL2
routine
lymphosarcoma
cells
were
partially
solubi-
lized
with
octylglucoside.
Reconstituted
membranes,
con-
sisting
mainly
of
unilamellar
vesicles
with
a
diameter
of
0.03-0.15
gm,
were
formed
by
detergent
removal
and
were
purified
by
floatation
in
a
discontinuous
sucrose
gra-
dient
to
remove
non-lipid-bound
protein.
Subcutaneous
immunization
of
syngeneic
mice
with
reconstituted
mem-
branes
or
with
purified
reconstituted
membranes
induced
protection
against
an
intraperitoneal
challenge
with
103
viable
SL2
cells.
Reconstituted
membranes
were
more
im-
munogenic
than
crude
membranes
in
immunoprotection
experiments
when
compared
on
the
basis
of
protein
dose.
Detergent
removal
was
required
to
obtain
an
immunogenic
presentation
form
of
SL2
membrane
antigens
and
to
avoid
toxicity
associated
with
the
detergent.
Reconstitution
of
SL2
membranes
in
the
presence
of
exogenous
phos-
pholipid
slightly
increased
the
fraction
of
protein
that
as-
sociated
with
the
reconstituted
membranes.
However,
the
immunogenicity
of
the
solubilized
membrane
TAA
was
not
significantly
affected
by
the
presence
of
exogenous
phospholipid.
The
reconstitution
procedure
described
may
be
useful
in
identifying
membrane
factors
required
for
the
induction
of
immune
responses
against
TAA.
The
versatil-
ity
of
the
system
may
be
employed
to
develop
safe
alterna-
tives
for
whole-cell
vaccines
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