Design Aspects of a Broadband Beam-Reconfigurable Leaky-Wave Antenna

Design aspects of a novel beam-reconfigurable pla-nar series-fed array are addressed to achieve beam steering with frequency tunability over a relatively broad bandwidth. The design is possible thanks to the use of the complementary strip-slot, which is an innovative broadly matched microstrip radiator, and the careful selection of the phase shifter parameters.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Dependence of exchange anisotropy and coercivity on the Fe–oxide structure in oxygen-passivated Fe nanoparticles

Ultrafine Fe particles have been prepared by the inert gas condensation method and subsequently oxygen passivated. The as-obtained particles consist in an Fe core surrounded by an amorphous Fe-oxide surface layer. The antiferromagnetic character of the Fe-oxide surface induces an exchange anisotropy in the ferromagnetic Fe core when the system is field cooled. Samples have been heat treated in vacuum at different temperatures. Structural changes of the Fe–O layer have been monitored by x-ray diffraction and transmission electron microscopy. Magnetic properties as coercivity, hysteresis loop shift, and evolution of magnetization with temperature have been analyzed for different oxide crystallization stages. A decrease of the exchange anisotropy strength is reported as the structural disorder of the surface oxide layer is decreased with thermal treatment

Dependence of exchange anisotropy and coercivity on the Fe–oxide structure in oxygen-passivated Fe nanoparticles

Ultrafine Fe particles have been prepared by the inert gas condensation method and subsequently oxygen passivated. The as-obtained particles consist in an Fe core surrounded by an amorphous Fe-oxide surface layer. The antiferromagnetic character of the Fe-oxide surface induces an exchange anisotropy in the ferromagnetic Fe core when the system is field cooled. Samples have been heat treated in vacuum at different temperatures. Structural changes of the Fe–O layer have been monitored by x-ray diffraction and transmission electron microscopy. Magnetic properties as coercivity, hysteresis loop shift, and evolution of magnetization with temperature have been analyzed for different oxide crystallization stages. A decrease of the exchange anisotropy strength is reported as the structural disorder of the surface oxide layer is decreased with thermal treatment

Drag reduction on a blunt body by self-adaption of rear flexibly hinged flaps

We study the aerodynamics of a blunt-based body with rear flexibly-hinged rigid flaps, subject to a turbulent flow of Reynolds number Re = 12000, under aligned and cross flow conditions with yaw angle β = 0◦ and β = 4◦. To that aim, different values of the equivalent torsional stiffness are considered, to cover the range of reduced velocity U∗ = (0, 3.48] in water tank experiments. The effect of the angular deflection of plates on the drag and near wake flow is analyzed, experimentally and numerically. The results show that, in the range of U∗ herein considered, the plates undergo an inwards quasi-static, self-adaptive deflection, which is symmetric for yaw angles β = 0◦ and asymmetric for β = 4◦. In particular, the plates feature small mean deformation angles for values of U∗ < 1, whereas a sharp and monotonic increase of such deflection occurs for U∗ > 1, i.e. for lower values of the hinge’s stiffness, with an asymptotic trend towards the larger values of U∗. A critical value of reduced velocity of U∗ ≃ 0.96 is obtained as the instability threshold above which plates depart from their initial equilibrium position. The progressive streamlining of the trailing edge translates into significant reductions of the associated mean drag coefficients. Thus, reductions close to 19% with respect to reference static plates configurations are obtained for the most flexible case of U∗ = 3.48 for both β = 0◦ and β = 4◦. A close inspection of the near wake reveals that the inwards progressive mean displacement of the plates yields a reduction in the recirculation bubble size. A symmetric evolution of the recirculating bubble is observed for β = 0◦, whereas the bubble becomes asymmetric for β = 4◦, with a larger leeward clockwise vortex. In both cases, the drag coefficient is shown to vary linearly with the global aspect ratio of the recirculating bubble. The analysis of the numerical results shows that the reduced extension of the recirculating bubble significantly alters the formation length and intensity of the eddies size and associated pressure. It is observed that despite the local pressure decrease in the vortices shed from the trailing edges, the plates self adaption reduces their size and prevents the eddies from entering the cavity, thus, creating a dead flow region with a consequent pressure increase at the body base.Junta de Andalucia FEDER-UJA 1262764Universidad de JaenEuropean CommissionSpanish MCIN/AEI PDC2021-121288-I00European Union Next Generation EU/PRT

Microdeterminación espectrofotométrica de Cu (II) por extracción de su complejo con 5,7-d¡bromo-8-hidrox¡qu¡noleína

The charasterictics of the Cu(II)-dibromoxine complex and its extraction into organic solvents are studied. In alkaline m&eacute;dium the formation of the complex and its extraction into chloroform is very selective. As result a new extractive spectrophotometric method for determination of copper (molar absorptivity 6,3&middot;104 l.mol-1&middot;cm-1) between 0,3-0,7 {xg/ml, is proposed. The new method showing a standard desviation of 0,24 %, has been succesfuUy applied to the Cu(II) analysis 0,04-0,06 %) in metallic lead.Se estudian las caracter&iacute;sticas del complejo de Cu(II) con 5,7-dibromo- -8-hidroxiquinole&iacute;na (dibromoxina) y su extracci&oacute;n en disolventes org&aacute;nicos. En medio alcalino la formaci&oacute;n y extracci&oacute;n en cloroformo es muy selectiva. De las investigaciones realizadas se propone un nuevo m&eacute;todo para la determinaci&oacute;n espectrofotom&eacute;trica de cobre entre 0,3- 0,7 ug/ml, la absortividad molar del complejo es 6,3&middot;104 l.mol-1cm-1. La desviaci&oacute;n est&aacute;ndar es 0,24 %. El m&eacute;todo se ha aplicado con excelentes resultados para la determinaci&oacute;n de cobre en muy peque&ntilde;a cantidad, en plomo met&aacute;lico

Integrating clinical research in an operative screening and diagnostic breast imaging department: First experience, results and perspectives using microwave imaging.

Clinical research is crucial for evaluating new medical procedures and devices. It is important for healthcare units and hospitals to minimize the disruptions caused by conducting clinical studies; however, complex clinical pathways require dedicated recruitment and study designs.This work presents the effective introduction of novel microwave breast imaging (MBI), via MammoWave apparatus, into the clinical routine of an operative screening and diagnostic breast imaging department for conducting a multicentric clinical study. Microwave breast imaging, using MammoWave apparatus, was performed on volunteers coming from different clinical pathways. Clinical data, comprising demographics and conventional radiologic reports (used as reference standard), was collected; a satisfaction questionnaire was filled by every volunteer. Microwave images were analyzed by an automatic clinical decision support system, which quantified their corresponding features to discriminate between breasts with no relevant radiological findings (NF) and breasts with described findings (WF). Conventional breast imaging (DBT, US, MRI) and MBI were performed and adapted to assure best clinical practices and optimum pathways. 180 volunteers, both symptomatic and asymptomatic, were enrolled in the study. After microwave images' quality assessment, 48 NF (15 dense) and 169 WF (88 dense) breasts were used for the prospective study; 48 (18 dense) breasts suffered from a histology-confirmed carcinoma. An overall sensitivity of 85.8 % in breasts lesions' detection was achieved by the microwave imaging apparatus. An optimum recruitment strategy was implemented to assess MBI. Future trials may show the clinical usefulness of microwave imaging, which may play an important role in breast screening. [Abstract copyright: © 2023 The Authors.

Predicting the academic underachievement in high school in Spain over the next few years: A dynamic modelling approach

[EN] In this paper we propose a dynamic model to understand the evolution of the academic underachievement in a high school in Spain. This model is based on ideas of Christakis and Fowler where individual habits may be transmitted by social contact. Thus, to build the model we suppose that a student has academic failure when she/he gets into study habits transmitted by students with bad academic habits. From the available academic results of the Spanish high school educational system during the period 1999 2008, we fit the model to the data in order to obtain the parameters of the model. Then, we predict the academic underachievement evolution over the next few years.This work has been partially supported by the Spanish M.C.Y.T. grant MTM2009-08587 and the Universitat Politecnica de Valencia grant PAID06-09-2588Camacho Vidal, FJ.; Cortés, J.; Micle, RM.; Sánchez-Sánchez, A. (2013). Predicting the academic underachievement in high school in Spain over the next few years: A dynamic modelling approach. Mathematical and Computer Modelling. 57(7):1703-1708. https://doi.org/10.1016/j.mcm.2011.11.011S1703170857

Potencial utilización de la termografía infrarroja para la lectura de la IDTB en cabras

En este trabajo se pretende estudiar la potencial utilización de la TI (Termografía infrarroja) en la lectura de la IDTB (intradermotuberculinización) en cabras. El análisis de las temperaturas mostró un aumento significativo a las 24h postinoculación de la tuberculina en el conjunto de los individuos, no observándose influencia significativa de la capa de los animales sobre las temperaturas. La comparación de los resultados de ambas técnicas no evidenció asociación significativa.The aim of this experiment is to study the potential use of IT (infrared termography) for measurement of PPD (Purified protein derivate) test in goats. The study of the temperatures showed a significant increase at 24hours post-inoculation of the PPD in the set of all the individuals, not being observed significant influence of the colour of the animals on the temperatures. The comparison of the results from the PPD skin test, and IT did not demonstrate significant association

Dependence of exchange anisotropy and coercivity on the Fe–oxide structure in oxygen-passivated Fe nanoparticles

3 pages, 5 figures.Ultrafine Fe particles have been prepared by the inert gas condensation method and subsequently oxygen passivated. The as-obtained particles consist in an Fe core surrounded by an amorphous Fe-oxide surface layer. The antiferromagnetic character of the Fe-oxide surface induces an exchange anisotropy in the ferromagnetic Fe core when the system is field cooled. Samples have been heat treated in vacuum at different temperatures. Structural changes of the Fe–O layer have been monitored by x-ray diffraction and transmission electron microscopy. Magnetic properties as coercivity, hysteresis loop shift, and evolution of magnetization with temperature have been analyzed for different oxide crystallization stages. A decrease of the exchange anisotropy strength is reported as the structural disorder of the surface oxide layer is decreased with thermal treatment.Peer reviewe

Production of extracts with anaesthetic activity from the culture of Heterosigma akashiwo in pilot-scale photobioreactors

The shear-sensitive microalga Heterosigma akashiwo is known to produce brevetoxin-like compounds that are active in voltage-dependent sodium channels. In this work, we present a study on the production of anaesthetic extracts from H. akashiwo biomass obtained in low-shear bioreactors at different growth phases. The photobioreactors (PBRs) used had specific configurations and were operated in such a way as to avoid cellular damage by hydrodynamic stress. Cultures were developed in small static-control flasks and PBRs with volumes ranging from 1.5 L to 200 L. The bioactivity of the produced extracts was assessed in vitro (Neuro-2a cell-based assay) and in vivo (Zebra fish model). Bioactivity depended slightly on the growth phase and culture system, with greater toxicity with the Neuro-2a model when stationary-phase extracts were used. Interestingly, extracts were not cytotoxic against other human cell lines. Steady production of anaesthetic bioactives was observed. In vivo anaesthetic efficacy, assessed with the Zebra fish model, was similar to that of commercial products, and without any observed mortality at 24-h post exposure