279 research outputs found
Impact de l’usage des gants médicaux sur l’observance de l’hygiène des mains au cours des soins au Centre Hospitalier et Universitaire du Point G de Bamako
Objectif : Évaluer l'impact de l'usage des gants médicaux sur l'observance de l'hygiène des mains et promouvoir leur usage approprié.
Matériel et Méthodes: Il s’agissait d’une étude interventionnelle avec une évaluation avant et après intervention. Sa mise en œuvre a été réalisée entre avril 2010 et octobre 2011 au Centre Hospitalier et Universitaire du Point G. Le recueil du consentement éclairé et les observations ont été effectués auprès du personnel soignant ayant un contact direct avec les patients avant et après intervention. Ces observations ont été discrètes mais ouvertes, menées auprès des soignants préalablement informés du but et du programme des activités.
Résultats : Au total, 143 fiches de consentement éclairé ont été retournées sur une prévision de 274 fiches, soit 52,19%. Les observations ont donné un taux d’observance globale de 52,05% avant intervention contre 42,97% après intervention (p = 0,0017). Le taux global de port de gants était de 23,30% et 27,20% respectivement avant et après intervention (p = 0,12).
Conclusion : Les résultats des deux évaluations avant et après intervention ont montré une amélioration du taux global de port des gants qui n’était pas significative mais sans impact sur l’observance de l’hygiène des mains
Transport properties and microstructure of mono- and seven-core wires of FeSe1-xTex superconductor by Fe-diffusion powder-in-tube method
We report the successful fabrication of mono- and seven-core superconducting
wires of FeSe1-xTex using an in-situ Fe-diffusion process based on the
powder-in-tube (Fe-diffusion PIT) method. The reacted layer in these wires were
found to have composite structure with composition nearly FeSe and FeTe for the
inner and outer layers, although a single layer of composition FeSe0.5Te0.5 was
supposed to be formed. The self-field transport Jc values at 4.2 K were found
to be 226.2 A/cm2 and 100.3 A/cm2 respectively for mono- and seven-core wires.
The Jc's of mono- and seven-core wires dropped rapidly at low fields and then
showed a gradual decrease with increasing magnetic fields. In addition, the
seven-core wire showed higher Jc than the mono-core wire under higher magnetic
fields, indicating that the seven-core wire of FeSe1-xTex superconductor using
Fe-diffusion PIT method is advantageous for the superconducting-wire
application under high magnetic fields.Comment: 19 pages, 6 figure
From reverse innovation to global innovation in animal health: a review
Reverse innovation refers to learning from or diffusion of innovations developed in low income settings and further translated to industrialized countries. There is lack of consensus regarding terminology, but the idea that innovations in low-income countries are promising for adoption in high-income contexts is not new. However, in healthcare literature globally, the vast majority of publications referring to 'disruptive innovation' were published in the last ten years. To assess the potential of innovative developments and technologies for improving animal health, we initiated a literature review in 2020. We used a combined approach, incorporating targeted searching in PubMed using a key word algorithm with a snowball technique, to identify 120 relevant publications and extract data for qualitative coding. Heterogeneity of articles precluded meta-analysis, quality scoring and risk of bias analysis. We can distinguish technical innovations like new digital devices, diagnostic tests and procedures, and social innovations of intersectoral cooperation. We profile two case studies to describe potential global innovations: an integrated surveillance and response system in Somali Regional State, Ethiopia and a blockchain secured One Health intervention to optimally provide post-exposure prophylaxis for rabies exposed people in West Africa. Innovation follows no borders and can also occur in low-income settings, under constraints of cost, lack of services and infrastructure. Lower administrative and legal barriers may contribute to produce innovations that would not be possible under conditions of high density of regulation. We recommend using the term global innovation, which highlights those emanating from international partnership to solve problems of global implications
One-step synthesis of KxFe2-ySe2 single crystals for high critical current density
We have established a simple process that allows for the one-step synthesis
of KxFe2-ySe2 single crystals, which exhibit high critical current density Jc.
The post annealing and quenching technique has improved the homogeneity of
as-grown crystals, resulting in full shielding of the external magnetic field.
The quenched crystals show a superconducting transition at Tconset = 32.9 K and
Tczero = 32.1 K. The upper critical fields \mu_{0}Hc2(0) for H//ab and H//c are
estimated to be ~206 and ~50 T, respectively. The critical current densities Jc
for H//ab and H//c reach as high as 1.0\times10^{5} and 3.4\times10^{4} A/cm2
at 5 K. Furthermore, Jc exhibits a high field performance and a significantly
weak temperature dependence up to 5 T, suggesting strong pinning. These results
demonstrate that KxFe2-ySe2 would be a promising candidate material for
practical applications.Comment: 10 pages, 5 figure
The advanced LIGO input optics
The advanced LIGO gravitational wave detectors are nearing their design sensitivity and should begin taking meaningful astrophysical data in the fall of 2015. These resonant optical interferometers will have unprecedented sensitivity to the strains caused by passing gravitational waves. The input optics play a significant part in allowing these devices to reach such sensitivities. Residing between the pre-stabilized laser and the main interferometer, the input optics subsystem is tasked with preparing the laser beam for interferometry at the sub-attometer level while operating at continuous wave input power levels ranging from 100 mW to 150 W. These extreme operating conditions required every major component to be custom designed. These designs draw heavily on the experience and understanding gained during the operation of Initial LIGO and Enhanced LIGO. In this article, we report on how the components of the input optics were designed to meet their stringent requirements and present measurements showing how well they have lived up to their design
The Advanced LIGO Input Optics
The advanced LIGO gravitational wave detectors are nearing their design sensitivity and should begin taking meaningful astrophysical data in the fall of 2015. These resonant optical interferometers will have unprecedented sensitivity to the strains caused by passing gravitational waves. The input optics play a significant part in allowing these devices to reach such sensitivities. Residing between the pre-stabilized laser and the main interferometer, the input optics subsystem is tasked with preparing the laser beam for interferometry at the sub-attometer level while operating at continuous wave input power levels ranging from 100 mW to 150 W. These extreme operating conditions required every major component to be custom designed. These designs draw heavily on the experience and understanding gained during the operation of Initial LIGO and Enhanced LIGO. In this article, we report on how the components of the input optics were designed to meet their stringent requirements and present measurements showing how well they have lived up to their design
Quantum state preparation and macroscopic entanglement in gravitational-wave detectors
Long-baseline laser-interferometer gravitational-wave detectors are operating
at a factor of 10 (in amplitude) above the standard quantum limit (SQL) within
a broad frequency band. Such a low classical noise budget has already allowed
the creation of a controlled 2.7 kg macroscopic oscillator with an effective
eigenfrequency of 150 Hz and an occupation number of 200. This result, along
with the prospect for further improvements, heralds the new possibility of
experimentally probing macroscopic quantum mechanics (MQM) - quantum mechanical
behavior of objects in the realm of everyday experience - using
gravitational-wave detectors. In this paper, we provide the mathematical
foundation for the first step of a MQM experiment: the preparation of a
macroscopic test mass into a nearly minimum-Heisenberg-limited Gaussian quantum
state, which is possible if the interferometer's classical noise beats the SQL
in a broad frequency band. Our formalism, based on Wiener filtering, allows a
straightforward conversion from the classical noise budget of a laser
interferometer, in terms of noise spectra, into the strategy for quantum state
preparation, and the quality of the prepared state. Using this formalism, we
consider how Gaussian entanglement can be built among two macroscopic test
masses, and the performance of the planned Advanced LIGO interferometers in
quantum-state preparation
Searching for a Stochastic Background of Gravitational Waves with LIGO
The Laser Interferometer Gravitational-wave Observatory (LIGO) has performed
the fourth science run, S4, with significantly improved interferometer
sensitivities with respect to previous runs. Using data acquired during this
science run, we place a limit on the amplitude of a stochastic background of
gravitational waves. For a frequency independent spectrum, the new limit is
. This is currently the most sensitive
result in the frequency range 51-150 Hz, with a factor of 13 improvement over
the previous LIGO result. We discuss complementarity of the new result with
other constraints on a stochastic background of gravitational waves, and we
investigate implications of the new result for different models of this
background.Comment: 37 pages, 16 figure
Upper limits on the strength of periodic gravitational waves from PSR J1939+2134
The first science run of the LIGO and GEO gravitational wave detectors
presented the opportunity to test methods of searching for gravitational waves
from known pulsars. Here we present new direct upper limits on the strength of
waves from the pulsar PSR J1939+2134 using two independent analysis methods,
one in the frequency domain using frequentist statistics and one in the time
domain using Bayesian inference. Both methods show that the strain amplitude at
Earth from this pulsar is less than a few times .Comment: 7 pages, 1 figure, to appear in the Proceedings of the 5th Edoardo
Amaldi Conference on Gravitational Waves, Tirrenia, Pisa, Italy, 6-11 July
200
Improving the sensitivity to gravitational-wave sources by modifying the input-output optics of advanced interferometers
We study frequency dependent (FD) input-output schemes for signal-recycling
interferometers, the baseline design of Advanced LIGO and the current
configuration of GEO 600. Complementary to a recent proposal by Harms et al. to
use FD input squeezing and ordinary homodyne detection, we explore a scheme
which uses ordinary squeezed vacuum, but FD readout. Both schemes, which are
sub-optimal among all possible input-output schemes, provide a global noise
suppression by the power squeeze factor, while being realizable by using
detuned Fabry-Perot cavities as input/output filters. At high frequencies, the
two schemes are shown to be equivalent, while at low frequencies our scheme
gives better performance than that of Harms et al., and is nearly fully
optimal. We then study the sensitivity improvement achievable by these schemes
in Advanced LIGO era (with 30-m filter cavities and current estimates of
filter-mirror losses and thermal noise), for neutron star binary inspirals, and
for narrowband GW sources such as low-mass X-ray binaries and known radio
pulsars. Optical losses are shown to be a major obstacle for the actual
implementation of these techniques in Advanced LIGO. On time scales of
third-generation interferometers, like EURO/LIGO-III (~2012), with
kilometer-scale filter cavities, a signal-recycling interferometer with the FD
readout scheme explored in this paper can have performances comparable to
existing proposals. [abridged]Comment: Figs. 9 and 12 corrected; Appendix added for narrowband data analysi
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