67,688 research outputs found
Screening for Infectious diseases among newly arrived migrants. experiences and practices in non-EU countries of the Mediterranean basin and Black Sea
Changing migration dynamics in the Mediterranean Sea and differences in infectious diseases (ID) burden between the countries of origin have raised questions whether public health actions are needed to avoid the transmission of ID. Screening newly arrived migrants for ID is one health monitoring option, offering opportunities for prevention, early detection and treatment. The authors conducted a survey among country experts in non-European Union countries of the Mediterranean and Black Sea, in order to explore current ID screening practices and policies for newly arrived migrants. The association between the existence of guidelines and the proportion of refugees in the population was also estimated. Eighteen country experts responded (90%) out of the 20 invited. Eleven countries (61%) implemented screening programmes and six (38%) had national guidelines. Screening was performed most often for tuberculosis at the holding level. A higher proportion of refugees in the population was associated with the existence of guidelines for screening (p = 0.05). Fourteen experts (88%) considered screening among migrants useful. The results show that screening for ID in newly arrived migrants is relevant for non-EU countries of the Mediterranean and Black Sea. Common guidelines could be promoted focusing on both individual and public health benefits of screening programmesChanging migration dynamics in the Mediterranean Sea and differences in infectious diseases (ID) burden between the countries of origin have raised questions whether public health actions are needed to avoid the transmission of ID. Screening newly arrived migrants for ID is one health monitoring option, offering opportunities for prevention, early detection and treatment. The authors conducted a survey among country experts in non-European Union countries of the Mediterranean and Black Sea, in order to explore current ID screening practices and policies for newly arrived migrants. The association between the existence of guidelines and the proportion of refugees in the population was also estimated. Eighteen country experts responded (90%) out of the 20 invited. Eleven countries (61%) implemented screening programmes and six (38%) had national guidelines. Screening was performed most often for tuberculosis at the holding level. A higher proportion of refugees in the population was associated with the existence of guidelines for screening (p = 0.05). Fourteen experts (88%) considered screening among migrants useful. The results show that screening for ID in newly arrived migrants is relevant for non-EU countries of the Mediterranean and Black Sea. Common guidelines could be promoted focusing on both individual and public health benefits of screening programmes
Fast cold gas in hot AGN outflows
Observations of the emission from spatially extended cold gas around bright
high-redshift QSOs reveal surprisingly large velocity widths exceeding 2000 km
s^(-1), out to projected distances as large as 30 kpc. The high velocity widths
have been interpreted as the signature of powerful AGN-driven outflows.
Naively, these findings appear in tension with hydrodynamic models in which
AGN-driven outflows are energy-driven and thus very hot with typical
temperatures T = 10^6-7 K. Using the moving-mesh code Arepo, we perform
'zoom-in' cosmological simulations of a z = 6 QSO and its environment,
following black hole growth and feedback via energy-driven outflows. In the
simulations, the QSO host galaxy is surrounded by a clumpy circum-galactic
medium pre-enriched with metals due to supernovae-driven galactic outflows. As
a result, part of the AGN-driven hot outflowing gas can cool radiatively,
leading to large amounts (> 10^9 M_sun) of cold gas comoving with the hot
bipolar outflow. This results in velocity widths of spatially extended cold gas
similar to those observed. We caution, however, that gas inflows, random
motions in the deep potential well of the QSO host galaxy and cooling of
supernovae-driven winds contribute significantly to the large velocity width of
the cold gas in the simulations, complicating the interpretation of
observational data
On the S-wave piD-scattering length in the relativistic field theory model of the deuteron
The S-wave scattering length of the strong pion-deuteron (pi D) scattering is
calculated in the relativistic field theory model of the deuteron suggested in
[1,2].The theoretical result agrees well with the experimental data. The
important role of the Delta-resonance contribution to the elastic pi
D-scattering is confirmed.Comment: 7 pages, no figures, accepted for publication in Z. Phys.
Feedback from active galactic nuclei: Energy- versus momentum-driving
We employ hydrodynamical simulations using the moving-mesh code AREPO to
investigate the role of energy and momentum input from Active Galactic Nuclei
(AGN) in driving large-scale galactic outflows. We start by reproducing
analytic solutions for both energy- and momentum-driven outflowing shells in
simulations of a spherical isolated dark matter potential with gas in
hydrostatic equilibrium and with no radiative cooling. We confirm that for this
simplified setup, galactic outflows driven by a momentum input rate of order
L_Edd/c can establish an M_BH - sigma relation with slope and normalisation
similar to that observed. We show that momentum input at a rate of L_Edd/c is
however insufficient to drive efficient outflows once cooling and gas inflows
as predicted by cosmological simulations at resolved scales are taken into
account. We argue that observed large-scale AGN-driven outflows are instead
likely to be energy-driven and show that such outflows can reach momentum
fluxes exceeding 10 L_Edd/c within the innermost 10 kpc of the galaxy. The
outflows are highly anisotropic, with outflow rates and a velocity structure
found to be inadequately described by spherical outflow models. We verify that
the hot energy-driven outflowing gas is expected to be strongly affected by
metal-line cooling, leading to significant amounts (>10^9 M_sun) of entrained
cold gas
Transesterification of Jatropha oil using immobilized Pseudomonas fluorescens
Transesterification of vegetable oils is an important reaction that produces fatty acid alkyl esters, methyl and ethyl esters which are excellent substitutes for diesel fuel. Biodiesel prepared by catalyzedmild transesterification has become of much current interest for alternative fuel production. In the present study the ability of a commercial immobilized Pseudomonas fluorescens MTCC 103 to catalyze the transesterification of Jatropha oil and methanol was investigated. The cell of P. fluorescens was easily immobilized within the sodium alginate during batch process. The important parameters like reaction temperature, pH, oil/methanol molar ratio, amount of beads and reaction time was studied. From the study it was found that maximum yield of biodiesel was obtained at the optimum conditions ofat 40ÂşC, pH of 7.0, molar ratio of 1:4, amount of beads of 3 g and reaction time of 48 h. The physical properties of the products were analyzed and the results were compared with conventional petroleumbased diesel and it was found that the product can be used as an effective alternate fuel in existing diesel engine without any hardware engine modifications
Non-Abelian discrete gauge symmetries in 4d string models
We study the realization of non-Abelian discrete gauge symmetries in 4d field
theory and string theory compactifications. The underlying structure
generalizes the Abelian case, and follows from the interplay between gaugings
of non-Abelian isometries of the scalar manifold and field identifications
making axion-like fields periodic. We present several classes of string
constructions realizing non-Abelian discrete gauge symmetries. In particular,
compactifications with torsion homology classes, where non-Abelianity arises
microscopically from the Hanany-Witten effect, or compactifications with
non-Abelian discrete isometry groups, like twisted tori. We finally focus on
the more interesting case of magnetized branes in toroidal compactifications
and quotients thereof (and their heterotic and intersecting duals), in which
the non-Abelian discrete gauge symmetries imply powerful selection rules for
Yukawa couplings of charged matter fields. In particular, in MSSM-like models
they correspond to discrete flavour symmetries constraining the quark and
lepton mass matrices, as we show in specific examples.Comment: 58 pages; minor typos corrected and references adde
Historical trends and variability in heat waves in the United Kingdom
This is the final version of the article. Available from MDPI via the DOI in this record.Increases in numbers and lengths of heat waves have previously been identified in global temperature records, including locations within Europe. However, studies of changes in UK heat wave characteristics are limited. Historic daily maximum temperatures from 29 weather stations with records exceeding 85 years in length across the country were examined. Heat waves were defined as periods with unusually high temperatures for each station, even if the temperatures would not be considered warm in an absolute sense. Positive trends in numbers and lengths of heat waves were identified at some stations. However, for some stations in the south east of England, lengths of very long heat waves (over 10 days) had declined since the 1970s, whereas the lengths of shorter heat waves had increased slightly. Considerable multidecadal variability in heat wave numbers and lengths was apparent at all stations. Logistic regression, using a subset of eight stations with records beginning in the nineteenth century, suggested an association between the Atlantic Multidecadal Oscillation and the variability in heat wave numbers and lengths, with the summertime North Atlantic Oscillation playing a smaller role. The results were robust against different temperature thresholds.This work was funded under the National Institute for Health Research Health Protection Research Unit (NIHR HPRU) in environmental change and health, led by the London School of Hygiene and Tropical Medicine in partnership with Public Health England (PHE), the University of Exeter and the Met Office
Exclusive J/φ and γ photoproduction and the low x gluon
We discuss the potential to constrain the small-x PDFs using the exclusive production of heavy vector mesons. The calculation of J/φ and γ photoproduction at NLO in collinear factorisation is described. The different behaviour of the NLO corrections for J/φ and → is highlighted and we outline what might be expected from the inclusion of these processes in a PDF fit
Proteomic analysis of the cerebrospinal fluid of patients with Creutzfeldt-Jakob disease
So far, only the detection of 14-3-3 proteins in cerebrospinal fluid (CSF) has been accepted as diagnostic criterion for Creutzfeldt-Jakob disease (CJD). However, this assay cannot be used for screening because of the high rate of false-positive results, whereas patients with variant CJD are often negative for 14-3-3 proteins. The aim of this study was to compare the spot patterns of CSF by 2-dimensional polyacrylamide gel electrophoresis (2D-PAGE) to search for a CJD-specific spot pattern. We analyzed the CSF of 28 patients {[}11 CJD, 9 Alzheimer's disease ( AD), 8 nondemented controls (NDC)] employing 2D-PAGE which was optimized for minimal volumes of CSF (0.1 ml; 7-cm strips). All samples were run at least three times, gels were silver stained and analyzed by an analysis software and manually revised. We could consistently match 268 spots which were then compared between all groups. By the use of 5 spots, we were able to differentiate CJD from AD or NDC with a sensitivity of 100%. CJD could also be distinguished from both groups by using a heuristic clustering algorithm of 2 spots. We conclude that this proteomic approach can differentiate CJD from other diseases and may serve as a model for other neurodegenerative diseases. Copyright (C) 2007 S. Karger AG, Basel
- …