Enhancing magnetorheological effect using bimodal suspensions in the singlemultidomain limit

We demonstrate a new route to enhance the magnetorheological effect using bimodal suspensions in the single-multidomain limit. Experimental results are satisfactorily compared to 3D finite element method simulations. The physical reason behind this enhancement is the coating of the larger particles by the smaller ones due to the remnant magnetization of the latter.This work was supported by MAT 2016-78778-R and PCIN 2015-051 projects (FEDER FUNDS and MINECO, Spain). A J F Bombard is grateful to FAPEMIG grants: APQ-01824-17, PEE-00081-16, RED-00144-16, ETC-00043-15, PEP-00231- 15, APQ-00463-11 and RDP-00164-10. J R Morillas acknowledges FPU14/01576 fellowship

The RADMED monitoring program as a tool for MSFD implementation: toward an ecosystem based approach

In the western Mediterranean Sea, the RADMED monitoring programme is already conducting several of the evaluations required under the Marine Strategy Framework Directive (MFSD) along the Spanish Mediterranean coast. The different aspects of the ecosystem that are regularly sampled under this monitoring programme are the physical environment and the chemical and biological variables of the water column, together with the planktonic communities, biomass and structure. Moreover, determinations of some anthropogenic stressors on the marine environment, such as contaminants and microplastics, are under development. Data are managed and stored at the Instituto Español de Oceanografía (IEO) Data Centre that works under the Sea- DataNet infrastructure, and are also stored in the IBAMar database. In combination with remote sensing data, they are used to address open questions on the ecosystems in the western Mediterranean Sea.Postprint2,293

Visceral leishmaniasis caused by Leishmania infantum in a Spanish patient in Argentina: What is the origin of the infection? Case report

BACKGROUND: The question "Where have you been?" is a common one asked by doctors in Northern Europe and America when faced with clinical symptoms not typical of their country. This question must also arise in the clinics of developing countries in which non-autochthonous cases such as the one described here can appear. Important outbreaks of Leishmania infantum have been recorded in the last decade in several Latin American countries but its presence has not yet been recorded in Argentina. We report the first case of visceral leishmaniasis owing to L. infantum in this country. CASE PRESENTATION: A 71-year-old Spanish woman who has been living in Mendoza, Argentina, during the last 40 years presented with a history of high fever and shivering, anemia, leukopenia and splenomegaly over two years. Argentinian doctors did not suspect visceral leishmaniasis even when the histological analysis revealed the presence of "intracytoplasmatic spheroid particles compatible with fungal or parasitic infection". After a serious deterioration in her health, she was taken to Spain where she was evaluated and visceral leishmaniasis was established. Specific identification of the parasite was done by PCR-ELISA, isoenzyme electrophoresis and RAPD-PCR. CONCLUSION: We would like to point out that: i) cases such as the one described here, which appear in non-endemic areas, can pass unnoticed by the clinical physician. ii) in countries in which these introduced cases reside, in-depth parasitological studies are required into vectors and possible reservoirs to rule out the rare case of local infection and, once infection has taken place, to ensure that this does not spread by anthroponotic transmission or a competent reservoir

Simplifying the detection of MUTYH mutations by high resolution melting analysis

<p>Abstract</p> <p>Background</p> <p><it>MUTYH</it>-associated polyposis (MAP) is a disorder caused by bi-allelic germline <it>MUTYH </it>mutation, characterized by multiple colorectal adenomas. In order to identify mutations in <it>MUTYH </it>gene we applied High Resolution Melting (HRM) genotyping. HRM analysis is extensively employed as a scanning method for the detection of heterozygous mutations. Therefore, we applied HRM to show effectiveness in detecting homozygous mutations for these clinically important and frequent patients.</p> <p>Methods</p> <p>In this study, we analyzed phenotype and genotype data from 82 patients, with multiple (>= 10) synchronous (19/82) or metachronous (63/82) adenomas and negative <it>APC </it>study (except one case). Analysis was performed by HRM-PCR and direct sequencing, in order to identify mutations in <it>MUTYH </it>exons 7, 12 and 13, where the most prevalent mutations are located. In monoallelic mutation carriers, we evaluated entire <it>MUTYH </it>gene in search of another possible alteration. HRM-PCR was performed with strict conditions in several rounds: the first one to discriminate the heteroduplex patterns and homoduplex patterns and the next ones, in order to refine and confirm parameters. The genotypes obtained were correlated to phenotypic features (number of adenomas (synchronous or metachronous), colorectal cancer (CRC) and family history).</p> <p>Results</p> <p><it>MUTYH </it>germline mutations were found in 15.8% (13/82) of patients. The hot spots, Y179C (exon 7) and G396D (exon 13), were readily identified and other mutations were also detected. Each mutation had a reproducible melting profile by HRM, both heterozygous mutations and homozygous mutations. In our study of 82 patients, biallelic mutation is associated with being a carrier of ≥10 synchronous polyps (p = 0.05) and there is no association between biallelic mutation and CRC (p = 0.39) nor family history (p = 0.63). G338H non-pathogenic polymorphism (exon 12) was found in 23.1% (19/82) of patients. In all cases there was concordance between HRM (first and subsequent rounds) and sequencing data.</p> <p>Conclusions</p> <p>Here, we describe a screening method, HRM, for the detection of both heterozygous and homozygous mutations in the gene encoding <it>MUTYH </it>in selected samples of patients with phenotype of MAP. We refine the capabilities of HRM-PCR and apply it to a gene not yet analyzed by this tool. As clinical decisions will increasingly rely on molecular medicine, the power of identifying germline mutations must be continuously evaluated and improved.</p

Cruise Summary Report - MEDWAVES survey. MEDiterranean out flow WAter and Vulnerable EcosystemS (MEDWAVES)

The MEDWAVES (MEDiterranean out flow WAter and Vulnerable EcosystemS) cruise targeted areas under the potential influence of the MOW within the Mediterranean and Atlantic realms. These include seamounts where Cold-water corals (CWCs) have been reported but that are still poorly known, and which may act as essential “stepping stones” connecting fauna of seamounts in the Mediterranean with those of the continental shelf of Portugal, the Azores and the Mid-Atlantic Ridge. During MEDWAVES sampling has been conducted in two of the case studies of ATLAS: Case study 7 (Gulf of Cádiz-Strait of Gibraltar-Alboran Sea) and Case study 8 (Azores). The initially targeted areas in the Atlantic were: the Gazul Mud volcano, in the Gulf of Cádiz (GoC) area, included in the case study 7, and the Atlantic seamounts Ormonde (Portuguese shelf) and Formigas (by Azores), both part of the case study 8. In the Mediterranean the targeted areas were The Guadiaro submarine canyon and the Seco de los Olivos (also known as Chella Bank) seamount. Unfortunately it was not possible to sample in Guadiaro due to time constraints originated by adverse meteorological conditions which obligate us to reduce the time at sea focusing only in 4 of the 5 initially planned areas. MEDWAVES was structured in two legs; the first leg took place from the 21st September (departure from Cádiz harbour in Spain) to the 13th October 2016 (arrival in Ponta Delgada, São Miguel, Azores, Portugal took place the 8th of October due to the meteorological conditions that obligated to conclude the first leg earlier as planned). during the Leg 1 sampling was carried out in Gazul, Ormonde and Formigas. The second leg started the 14th October (departure from Ponta Delgada) and finished the 26th October (arrival in Málaga harbour, Spain). MEDWAVES had a total of 30 effective sampling days, being 6 days not operative due to the adverse meteorological conditions experienced during the first leg which forced us to stay in Ponta Delgada from the 08th to the 13th October. During MEDWAVES the daily routine followed a similar scheme, depending of course on the weather and sea conditions. The main activity during the day, starting early in the morning (around 08:00 AM, once the night activities were finished), was the ROV deployment. Generally a single ROV dive of around 8 hours was performed, however in several occasions two dives were carried out in the same day (see General station list, Appendix II). After the ROV (and sometimes between two dives) the Box Corer and/or Van Veen Grab and/or Multicore was deployed. After these activities, during the night CTD-Rosette deployments and MB was conducted. Accordingly to this schema the scientific personnel worked in the day or in the night watch. A total of 215 sampling stations have been covered in MEDWAVES, using the following sampling gears: Multibeam echosounder, CTD-Rosette, LADCP, Box Corer, Van Veen Grab, Multicorer and a Remotely Operated Vehicle (ROV). Table 1 sumamrised the number of sampling stations conducted with each gear in each sampling zone. Additionally MB surveys have been conducted during the transits between area

Protocolos RADMED (versión: 1.01 – 2014). Procedimientos a seguir en las campañas del proyecto RADMED

Los protocolos RADMED se pueden considerar como una guía de mar de las operaciones a realizar en el desarrollo de una campaña de ese proyecto, en donde figuran: el montaje del equipamiento científico, las secuencias de las diferentes operaciones y muestreos, la identificación de las estaciones, cómo rellenar los diferentes estadillos, las determinaciones de variables oceanográficas a bordo y el post-procesado de los datos hidrográficos. Detrás de todo ello está la intención de homogeneizar la información, para facilitar el post-procesado y el fiel tratamiento de las muestras y análisis.[Abstract] The RADMED protocols can be considered as a guide to work at the sea in the development of a campaign of this project and to conduct its different operations. They include: installation of scientific equipment, the sequences of the different operations and sampling, identification of stations, the filling of the various work sheets, determinations of oceanographic variables on board and the post processing of hydrographic data. All this pretend to standardize the information to facilitate post processing and accurate treatment of the samples and analysis

Non-linear Magnetorheology: multibody and multipole effects on the Yield Stress

Por lo general, los fluidos magnetorreológicos (FMR) son suspensiones de micropartículas ferromagnéticas dispersas en un líquido Newtoniano no magnético. Bajo la presencia de un campo magnético externo, las partículas se magnetizan y comienzan a interaccionar a través de fuerzas magnetoestáticas. Como resultado de dicha interacción, las partículas se ensamblan formando agregados en la dirección del campo externo dotando al sistema de una estructura interna. Esta estructuración tiene lugar en pocos milisegundos y da como resultado un notable incremento en la viscosidad de la suspensión (efecto MR). De hecho, para campos externos y concentraciones de partículas suficientemente elevados, la estructura interna es capaz de soportar esfuerzos (por debajo de un cierto valor conocido como esfuerzo umbral) sin romperse o fluir, comportándose entonces como un material sólido o viscoplástico [1]. La capacidad de controlar el comportamiento reológico (transición liquido-sólido) de forma rápida y precisa ha hecho de los FMR materiales muy apreciados como transmisores inteligentes de esfuerzo/torque en diversas ramas de la ingeniería [2]. Sin embargo, los FMR aún adolecen de diversas limitaciones que impiden su completa aplicación comercial. Entre otros: (i) no son fáciles de modelar cuantitativamente por lo que no es sencillo optimizar/predecir sus propiedades reológicas [3] y (ii) tienden a sedimentar y compactar con el tiempo lo que acaba convirtiéndolos en una pasta inmanejableTesis Univ. Granada.This work was supported by MINECO MAT 2016-78778-R and PCIN-2015-051 projects (Spain), European Regional Development Fund (ERDF) and by Junta de Andalucía P11-FQM-7074 project (Spain). J. R. Morillas acknowledges FPU14/01576 fellowship. A. J. F. Bombard is grateful to FAPEMIG grants: ETC-00043-15, PEE-00081-16, APQ-01824-17; and CNPq grant 200278/2018-5 (Brasil)

Design of smart lubricants using the inverse ferrofluid approach

We acknowledge F. Vereda for his help in the laboratory during the synthesis of magnetite particles. This work was supported by Total Marketing Services. J. de Vicente and R. Hidalgo-Alvarez acknowledge MICINN PID2019-104883GB-I00 project, Junta de Andalucia P18-FR2465 project and European Regional Development Fund (ERDF). J. R. Morillas acknowledges FPU14/01576 fellowship. Funding for open access charge by Universidad de Granada/CBUA is acknowledged.A new formulation is proposed to lubricate tribopairs in extreme conditions where the amount of lubricant is small and the lubricating region highly confined. It is composed of non-magnetic solid lubricants dispersed in an oil-based ferrofluid. When this inverse ferrofluid (IFF) is magnetically activated, the lubricant particles are subjected to magnetophoretic forces. By using appropriate magnetic field gradients, they can be driven to the region of interest and thus control the friction locally. The rheological and tribological performances of three IFF formulations are evaluated in several conditions of applied magnetic field strength and shear flow rates.Total Marketing ServicesSpanish GovernmentEuropean Commission PID2019-104883GB-I00Junta de Andalucia P18-FR2465European CommissionUniversidad de Granada/CBUAFPU14/0157

Colloidal stability and magnetic field-induced ordering of magnetorheological fluids studied with a quartz crystal microbalance

This work proposes the use of quartz crystal microbalances (QCMs) as a method to analyze and characterize magnetorheological (MR) fluids. QCM devices are sensitive to changes in mass, surface interactions, and viscoelastic properties of the medium contacting its surface. These features make the QCM suitable to study MR fluids and their response to variable environmental conditions. MR fluids change their structure and viscoelastic properties under the action of an external magnetic field, this change being determined by the particle volume fraction, the magnetic field strength, and the presence of thixotropic agents among other factors. In this work, the measurement of the resonance parameters (resonance frequency and dissipation factor) of a QCM are used to analyze the behavior of MR fluids in static conditions (that is, in the absence of external mechanical stresses). The influence of sedimentation under gravity and the application of magnetic fields on the shifts of resonance frequency and dissipation factor were measured and discussed in the frame of the coupled resonance produced by particles touching the QCM surface. Furthermore, the MR-fluid/QCM system has a great potential for the study of high-frequency contact mechanics because the translational and rotational stiffness of the link between the surface and the particles can be tuned by the magnetic field.This work was supported by the projects DPI2013-46915-C2-1-R and MINECO MAT 2013-44429-R and PCIN-2015-051 (Ministerio de Economía y Competitividad). This work was also supported by Junta de Andalucía P10-RNM-6630 and P11-FQM-7074 projects (Spain). J. R. M. acknowledges FPU14/ 01576 fellowship. We acknowledge support by the CSIC Open Access Publication Initiative through its Unit of Information Resources for Research (URICI).Peer Reviewe

Nanomechanical properties of novel intermetallic coatings developed on austenitic stainless steels by siliconisation in liquid phase

Advanced nanomechanical testing has been used to evaluate mechanical properties of Ni-free Al12(Fe,Cr)3Si2 intermetallic coatings grown on the 316 LVM steel by hot dipping in a Al-12.6 at.% Si liquid alloy for various immersion times. Despite the ultrafine-grained structure of the coating (∼200 nm), the indentation size effect is more pronounced for the intermetallic coating than for the steel, which is explained by the higher geometrical necessary dislocation (GND) density of the intermetallic coating. To determine the true hardness of the coatings, the model of Nix and Gao was used. It has been shown that the hardness of the coating decreases from 6.2 GPa for the shortest time of immersion (60 s), to 3.36 GPa for the highest immersion time (600 s), which is always much higher than that for the substrate (1.82 GPa). The decrease in both hardness and GND with increasing immersion time is related to the relaxation of residual stresses, which act as a hardening factor. The net effect is an increase of the plasticity index of the coating. Young's modulus for the intermetallic phase (146 GPa) is lower than that for the austenitic steel 316 LVM (220 GPa), which will favour the load transfer at the bone/metal interface, weakening the so-called >stress shielding effect>. Hence, the nanomechanical properties of this novel Ni-free intermetallic coating, tightly adhered to the substrate, offer a window of opportunity for orthopaedic applications. © 2010 Elsevier Ltd. All rights reserved.Peer Reviewe