451 research outputs found
Meeting the challenge of health system transformation in European countries
\ua9 The Author(s) 2022. Transforming health systems is a complex, messy business with no quick or simple solutions. Countries struggle to make it happen with policy failure often the result. Reporting on a World Health Organization Europe project aimed at understanding how health system transformation can succeed, the paper draws on three European country case studies to offer insights and lessons for policymakers elsewhere engaged in similar efforts. Critical to success in implementation is the adoption of a receptive context for change. Building on the policy capacity literature, it emphasizes the importance of environmental pressure, the quality and coherence of policy, leadership style, supportive organizational culture, and managerial-health profession relations
Tribological properties of tin and bronze coatings electrodeposited from acid baths
Electrodeposited copper, tin and bronze are widely used as protective and decorative coatings due to their good corrosion resistance and appearance. However, there are some applications in which these properties are not enough and a low coefficient of friction is required. It is known that tin has a good lubricity and that this property depends on the morphology of the deposit. Furthermore some authors have reported the use of electroplated bronze as a lubricating coating in the oil industry. The bath commonly used for the electrodeposition of this alloy is a cyanide-based electrolyte which produces high quality deposits but has several environmental problems during use and disposal owing to its high toxicity. Many cyanide free baths have been developed, either acid or alkaline, but too little information about the performance of the resulting deposits have been reported. The aim of this work is to develop an acidic noncyanide electrolyte for the electrodeposition of high quality bronze coatings and evaluate their tribological behavior.Centro de Investigación y Desarrollo en Tecnología de Pintura
Synthesis of 1,2-diaminotruxinic d-cyclobutanes by BF<sub>3</sub>-controlled [2 + 2]-photocycloaddition of 5(4<i>H</i>)-oxazolones and stereoselective expansion of d-cyclobutanes to give highly substituted pyrrolidine-2,5-dicarboxylates
The irradiation of (Z)-4-arylidene-5(4H)-oxazolones 1a–1u with blue light (465 nm) in the presence of the photosensitizer [Ru(bpy)3](BF4)2 (2.5 mol%) and the Lewis acid BF3·OEt2 (2 equiv.) in deoxygenated methanol at room temperature affords the corresponding 1,2-diaminotruxinic cyclobutane bis-amino esters 2a–2u stereoselectively as the δ-isomer. Characterization of cyclobutanes 2 shows that the photocycloaddition takes place by the coupling of two Z-oxazolones in a head-to-head 1,2-anti way. This change in the orientation of the coupling is promoted by O- or/and N-bonding of the BF3 additive. The δ-cyclobutanes 2 undergo a ring expansion when heated in methanol in the presence of NaOMe (1/1 molar ratio) to give densely substituted pyrrolidine-2,5-dicarboxylates 3 in a regio- and stereoselective way. The mechanism of the cyclobutane-to-pyrrolidine ring expansion has been elucidated using DFT methods
Quantification of the influence of the C, Cr and P contents on the permeability of hydrogen through Fe alloys
[EN] Ferritic-martensitic steels are candidate materials for blanket structural components of future thermonuclear fusion reactors. However, the tritium inventory that can be retained in different components of the reactor and its ability to migrate through the walls of any material may affect the correct operation of any fusion device. Therefore, the permeability of hydrogen isotopes through ferritic-martensitic steels, which depends on its metallurgical composition, becomes a key issue.
The European Fusion Development Agreement (EFDA) supplied 9 Fe alloys with controlled chemical alloying element contents and microstructure. The main alloying elements were C, Cr and P and they appeared in various concentrations in the 9 alloys. They were experimentally analyzed by means of the gas evolution permeation technique with temperatures ranging from 423 K to 823 K and for high purity hydrogen loading pressures ranging from 5.0 x 102 Pa to 1.5 x 105 Pa. The transport regime turned out to be diffusive and it was studied in depth, so that the permeability of each alloy was characterized by an Arrhenius-type regression for the aforementioned temperature range.
This work summarizes all the experimental measurements carried out for the permeability of hydrogen through the 9 alloys. It provides a quantification of the influence of the composition of the alloy on this transport parameter, posing different mathematical expressions for the variation of the permeability as a function of the contents of C, Cr and P.This work has been carried out in the framework of research projects funded by the Spanish Ministry of Science and Innovation (MEC08/98) , the University of the Basque Country (UPV/EHU-EHU08-34) and the European Fusion Development Agreement (EFDA MAT-REMEV) . The authors would also like to thank the FEMaS Coordinated Action project for the support in knowledge exchange among different research groups and Pilar Fernandez from CIEMAT for the preparation of the tested samples
Structural interaction between bone and implants due to arthroplasty of the first metatarsophalangeal joint
Background: Currently, the metatarsophalangeal joint replacement through a restorative arthroplasty, where implants are used, is a viable invasive surgical medical procedure in the treatment of severe cases of osteoarthritis in this joint, better known as hallux rigidus. However, few things are known about the postoperative complications that implants can cause on the joint, like Swanson and Tornier implants.Research in this field can provide a valuable information that would help the specialist surgeon in the decision-making during the selection of the more suitable joint implant in each patient, as well as the redesign of the devices, to make them more efficient, durable and biocompatible with the human body.
Methods: The aim of this work is to perform a structural biomechanical analysis of a restorative arthroplasty of the first metatarsophalangeal joint, and to analyze the interaction between bone and medical grade silicone implants. For that, a simulation of a foot with Swanson and Tornier joint implants were performed to evaluate the stress/strain distribution during a critical stage (toe-off).
Results and conclusions: Principal stresses obtained for the first metatarsal with both implants suggest that failure is induced in this bone because, values exceed (up to 136.84% for Swanson model) the tensile strength reported for phalange trabecular bone, which may be related to osteolysis. Stress and strain values obtained in this work suggest that arthroplasty surgery with Swanson implant is more likely to cause postoperative complications versus Tornier implant
Effectiveness of the Lapidus plate system in foot surgery: A PRISMA compliant systematic review
Lapidus arthrodesis is an established standard procedure to correct various foot surgery problems and hallux limitus, hypermobility of the first ray, hallux abductus valgus, and symptomatic lesser metatarsal. After decades, many fixation methods in the orthopaedic surgery industry have been developed for decreasing complications and improving this technique. The aim of this PRISMA compliant systematic review is to analyse the effectiveness of several lapidus plate systems in foot surgery. We have carried out the first systematic review of the relevant published literature so as to systematically evaluate the scientific knowledge available now on this association, assigning predefined eligibility criteria. Fourteen studies were selected which had an overall of 738 cases. The first tarsal metatarsal joint and hallux valgus were treated by the application of different types of Lapidus plate system. The optimal level of the fixation in these procedures is related with the type and system insertion place of the plate with or without screw in each specific foot disease. There is an insufficient number of studies about the effectiveness of the different types of Lapidus plate system in foot surgery, and there is a need to increase outcomes knowledge on the level of the fixation, sort of the system, and insert place in foot surgery
Winograd technique. About one case
Una de las técnicas quirúrgicas de elección para las onicocriptosis severas es el Winograd. En el presente artículo presentamos el caso de un varón de 17 años, afecto de onicocriptosis severa, con los rodetes ungueales hipertróficos al que sometimos a cirugía ungueal con resultados satisfactorios tanto para él como para los profesionales que llevamos a cabo la intervención.One of the surgical techniques of election for the severe onicocriptosis is the Winograd. In the present article we presents the clinical case of a man of 17 years old, affected of severe onicocriptosis, with the nails fols hypertrophied who underwent to nail surgery with satisfactory results for him as for the professionals as much who we carried out the intervention
Cationic exchange in nanosized ZnFe2O4 spinel revealed by experimental and simulated near-edge absorption structure
The non-equilibrium cation site occupancy in nanosized zinc ferrites (6-13
nm) with different degree of inversion (0.2 to 0.4) was investigated using Fe
and Zn K-edge x-ray absorption spectroscopy XANES and EXAFS, and magnetic
measurements. The very good agreement between experimental and ab-initio
calculations on the Zn K-edge XANES region clearly show the large
Zn2+(A)--Zn2+[B] transference that takes place in addition to the
well-identified Fe3+[B]--Fe3+(A) one, without altering the long-range
structural order. XANES spectra features as a function of the spinel inversion
were shown to depend on the configuration of the ligand shells surrounding the
absorbing atom. This XANES approach provides a direct way to sense cationic
inversion in these spinel compounds. We also demonstrated that a mechanical
crystallization takes place on nanocrystalline spinel that causes an increase
of both grain and magnetic sizes and, simultaneously, generates a significant
augment of the inversion.Comment: 5 pages, 5 eps figures, uses revtex4, corrected table
Citizen science provides a reliable and scalable tool to track disease-carrying mosquitoes
Recent outbreaks of Zika, chikungunya and dengue highlight the importance of better understanding the spread of disease-carrying mosquitoes across multiple spatio-temporal scales. Traditional surveillance tools are limited by jurisdictional boundaries and cost constraints. Here we show how a scalable citizen science system can solve this problem by combining citizen scientists'' observations with expert validation and correcting for sampling effort. Our system provides accurate early warning information about the Asian tiger mosquito (Aedes albopictus) invasion in Spain, well beyond that available from traditional methods, and vital for public health services. It also provides estimates of tiger mosquito risk comparable to those from traditional methods but more directly related to the human-mosquito encounters that are relevant for epidemiological modelling and scalable enough to cover the entire country. These results illustrate how powerful public participation in science can be and suggest citizen science is positioned to revolutionize mosquito-borne disease surveillance worldwide
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