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Introduction: the Achilles tendon is the most resistant tendon structure in the human body. Although it raises an injury prevalence of 24% within the population of runners, which increases exponentially at the international level. Objectives: We analyze the influence of the running technique on the architecture of the Achilles tendon, and we look for other factors that also influence its morphology. Methods: An observational, cross-sectional and descriptive study was carried out; thirty-three healthy habitual running subjects voluntarily participated. We carried out an orthogonal study of the tendon structure, obtaining values of diameter, perimeter, and microcirculation; the results were related to the runners' technique. Results: no significant differences were found regarding the influence of the running technique on the architecture of the Achilles tendon, observing that it was more significantly influenced by gender, height, and training. Conclusions: Although the running technique does not influence the thickness of the Achilles tendon, the influence of the technique on other characteristics of the tendon should continue to be studied.

Amyloidosis is a heterogeneous group of disorders characterised by extracellular deposition of amorphous proteinaceous material in various tissues. Primary bladder amyloidosis is a rare disease and its presentation is of clinical interest for the urologist because it resembles that of a malignant bladder tumour. Transurethral resection and histological examination is essential to exclude malignancy and to demonstrate the presence of amyloidosis. It is also important to exclude systemic amyloidosis. A new case is presented of primary bladder amyloidosis, briefly discussing its clinical, treatment, and monitoring.

The work describes the microwave behavior of polymer composites containing parallel Fe-based and continuous/short-cut Co-based microwire arrays. A magnetic field-tunable metacomposite feature has been identified in the hybrid microwires composite containing 3 mm spaced Co-based wires and confirmed by the presence of transmission windows in the frequency band of 1–3.5 GHz. The magnetically tuned redshift-blueshift in the transmission window is due to the competing dynamic interactions between the different wires and the ferromagnetic resonance of the Fe-based microwires. When the Co-based inter-wire spacing is increased to 10 mm, dual-band transmission windows in the 1.5–3.5 GHz and 9–17 GHz bandwidths were observed. These transmission windows are likely induced by the ferromagnetic resonance of Fe-based wires and the long range dipolar resonance arising between Fe–Co wire couples. The hybridization of parallel Fe-based and short Co-based wires in the composites leads to a significant enhancement of the transmission window in the 1–6 GHz band due to the band-gap nature of the Co-based wires. The hybrid metacomposites containing microwires seem attractive in radio frequency identification application.

Introduction The purpose of this study was to determine the effectiveness and harms of periprostatic block compared with other interventions in patients with clinically suspected prostate cancer who underwent transrectal biopsy to diminish pain. Material and methods We included only clinical trials which involved male adults older than 18 years-old suspected of having prostate cancer. The intervention performed was a periprostatic block and the comparators were topical anesthetics, sedatives, placebo/no intervention or combined therapies. The primary outcome was perianal or perineal pain and serious adverse effects (SAE). Literature search was conducted in MEDLINE, EMBASE, LILACS, CENTRAL and non-published literature from inception to March 2019. We performed a network meta-analysis in R. Results We included 43 studies in the meta-analysis. Thirteen studies compared periprostatic block vs. placebo/no intervention (the most frequent). Most of the studies had an unclear risk of bias for selection, performance and detection bias and low risk for attrition, reporting and other bias. Periprostatic block (lidocaine) + intrarectal gel (lidocaine + prilocaine) vs. periprostatic block (lidocaine) showed an RR -0.9 (95%CI - 1.9 to 0.074); intrarectal gel (lidocaine) vs. periprostatic block (lidocaine) had a RR 0.77 (95%CI 0.14 to 1.4); placebo/no intervention vs. periprostatic block (lidocaine) + intrarectal gel (lidocaine+prilocaine) RR 3 (95%CI 1.9 to 4); intrarectal gel (lidocaine) versus periprostatic block (lidocaine) + intrarectal gel (lidocaine + prilocaine) RR 1.7 (95%CI 0.64 to 2.7). Conclusions The blockage of the periprostatic plexus in the performance of a transrectal ultrasound-guided prostatic biopsy, alone or in combination with intrarectal analgesia or sedation, is an effective method to reduce pain.

The new Patent Law 24/2015 has produced a revision and an update of the invention protection system in Spain. This new legal framework aims to modernise and adapt the system of granting patents to the most developed countries and to promote a quality patent system that helps the internationalisation of companies. The article analyses the impact of a set of indicators, at quantitative and qualitative levels, in the short period of time that has elapsed since the entry into force of the new law, and has allowed identifying some trends that should be studied in the next years. From a quantitative point of view, there has been a decrease in the number of patent applications. Nevertheless, from the qualitative perspective, it can be affirmed that the objectives related to the increase in the quality of patent applications established in the new Patent Law are being met.

To establish the efficacy of antibiotic prophylaxis prior to cystoscopy in outpatients in decreasing the incidence of post-procedure urinary tract infection. A randomized clinical trial in patients (men and women) older than 18 who underwent cystoscopy for any non-urgent indication. The intervention was Levofloxacin 500 mg single dose, and the control was placebo 500 mg single dose made with similar characteristics. The primary outcome was urinary tract infection (UTI) measured 3–10 days after the procedure. It was performed as per protocol analysis. Hundred and thirty-eight patients in each study arm completed the trial. The incidence of UTI in the intervention group was 0.7 % and in the placebo group was 3 % (p = 0.17), and no significant differences were found. The incidence of asymptomatic bacteriuria in the intervention group was 5.8 % and in the control group was 14.5 % (p = 0.01). No significant differences were found in the use of prophylactic antibiotic compared to placebo to reduce the incidence of UTI in patients who undergo cystoscopy as an outpatient procedure with sterile urine demonstrated by urine culture.

Metamaterials have attracted tremendous research interest due to their fascinating unusual properties that are not available from nature, such as negative refractive index, reverse Doppler Effect, negative compressibility, etc. [1]. However, conventional metamaterials are simply structures as their special properties are independent to intrinsic properties of building blocks, which tarnishes their application perspectives to a large extent. Ferromagnetic microwires have been reported feasible to create electromagnetically double negative (DNG) medium by arranging them in a parallel [2] and orthogonal manner [3]. Recently we proposed the concept of metacomposites containing Fe-based microwires and revealed their DNG properties in line with advantages such as structural integrity and economic processing over metamaterials [4, 5]. Herein, as a step further, metacomposites containing hybrid Co- and Fe-based microwire arrays with different topology are designed and fabricated. A tunable DNG feature under external dc magnetic field is observed in the metacomposite containing continuous wire arrays evidenced by transmission windows and a negative dielectric permittivity dispersion. A DNG/band stop characteristic is observed in the metacomposite containing short-cut wires confirmed by a dip at 6 GHz in the transmission spectrum.

[EN] We report on free space transmission experiments carried out on stacked split ring resonator (SRRs) arrays operating at microwave frequencies. We start from the case of a single frequency selective surface which exhibits a rejection at the SRR resonance frequency. By stacking SRR arrays in the propagation direction, we then show experimentally the possibility to induce a transmission band just below this resonance frequency. Full wave analysis shows the role played by the longitudinal and transverse coupling effects in the electromagnetic properties of such bulk metamaterials, with the appearance of a transmission band resulting from an artificial magnetic activity., The authors acknowledge the assistance of Mr. Antonio Vila in the fabrication of the prototypes. J. C. acknowledges the financial support of MICINN, Spain (Contract numbers: TEC 2007-67239 and Consolider CSD2008-00066) and also USTL (France).

International audience; Three types of coplanar transmission lines loaded with split-ring resonators (SRRs) and including series gaps and/or shunt wires are analyzed in this letter. The phase advance originally predicted for these microstructures can be modified and their frequency selectivity can be enhanced while maintaining the advantage of miniaturization. Full-wave electromagnetic simulations and measurement of different prototypes operating in S- and C-frequency bands are performed for retrieving the effective permittivity and permeability. It is shown that right-handed transmission bands can be obtained slightly below the resonance frequency of the SRRs, giving an effective control of the propagation characteristics in magnitude and phase of these planar transmission lines.

The experimental demonstration of the total absorption of electromagnetic P-waves impinging on a low-loss dielectric thin layer covering a patterned metallic surface is here reported. A semi-analytical model has been employed to design a metallic grating of coaxial cavities that enhances the absorbing properties of the dielectric thin layer covering the surface. The experimental characterization of three samples shows that total absorption peaks are obtained at the frequencies predicted by the model. It is also demonstrated that the peak position is tunable with the cavity length.

It is widely known that the presence of disorder leads to an exponential localization of waves in one-dimensional random media, as predicted by Anderson. In this work, however, we provide experimental evidence that waves can be anomalously localized, in relation to the standard Anderson localization, by introducing random configurations of the disorder that follow a distribution with a power-law tail, i.e., a Levy-type distribution. Using a microwave waveguide with dielectric slabs randomly placed, we show that if the spacing between slabs follow a Levy-type distribution, unconventional properties in the microwave-transmission fluctuations appear, revealing the presence of anomalous localization. Our analytical model describes the experimental results for the statics of the transmission fluctuations. Effects of anomalous localization on the transmission are compared with those from the standard Anderson localization as well.

This work presents an experimental demonstration of total absorption by a metal-dielectric metasurface. Following a theoretical proposal [Dıaz-Rubio et al., Phys. Rev. B 89, 245123 (2014)], we have designed and fabricated a metasurface consisting of a low absorbing dielectric layer (made of FR4) placed on top of a metallic surface patterned with a square array of coaxial cavities. For p-polarized waves, a low frequency peak with perfect absorption is observed. The behavior of this peak has been experimentally characterized for different dielectric layer thicknesses, coaxial cavity lengths, and angles of incidence. The experimental results are in excellent agreement with numerical simulation and corroborate the theoretical predictions., This work was partially supported by the Spanish Ministerio de Economia y Competitividad (MINECO) under Contract No. TEC2010-19751 and the USA office of Naval Research, under Grant No. N000141210216. A. Hibbins acknowledges support from the UK Grant No. EEBB-I-1408331. We thank useful discussions with Daniel Torrent and the technical help of Benjamin Tremain.

We investigate the microwave behavior of polymer-based metacomposites containing ferromagnetic microwires and carbon fibers. A notable transmission window is observed from the metacomposite containing 3mm spaced parallel microwire array in 1-7 GHz, verifying a left-handed behavior. In the hybrid metacomposites containing both parallel wires and carbon fibers, such transmission window is preserved with a much higher transmittance due to the improved impedance match and hence decreased reflection loss. The introducing of continuous carbon fibers leads to a remarkable anisotropic behavior: left-handed properties are turned on/off by rotating the electric excitation by 90 degrees. The proposed metacomposites are promising for microwave cloaking and sensing applications for aerospace-graded structural components.

The absorption enhancement by lossy dielectric layers backed by metallic metasurfaces has been studied. A rigorous analysis based on mode matching theory has been used for obtaining analytical expressions for the peak position and for total absorption.

The absorption of electromagnetic waves by a thin dielectric slab backed by a metasurface has been comprehensively studied and discussed at microwave frequencies. The metasurface consists of a metallic plate decorated with a periodic distribution of coaxial- or annular-type cavities. Analytical expressions for the absorbance have been obtained by using a mode-matching method. For P-polarized waves it is predicted that a low-frequency peak of perfect absorption is possible by properly choosing the lossy component of the permittivity of the dielectric slab, with the position of this peak being easily tunable by the cavity length. It is also shown that non-Bravais lattices, containing several cavities in the unit cell, and the excitation of guided waves by the periodic array of resonators are complementary absorption mechanisms in the studied structures., This work was partially supported by the Spanish Ministerio de Economia y Competitividad (MINECO) under contract TEC2010-19751 and by the US Office of Naval Research.

The behavior of strongly coupled Radial Photonic Crystals shells is investigated as a potential alternative to transfer electromagnetic energy wirelessly. These sub-wavelength resonant microstructures, which are based on anisotropic metamaterials, can produce efficient coupling phenomena due to their high quality factor. A configuration of selected constitutive parameters (permittivity and permeability) is analyzed in terms of its resonant characteristics. The coupling to loss ratio between two coupled resonators is calculated as a function of distance, the maximum (in excess of 300) is obtained when the shells are separated by three times their radius. Under practical conditions an 83% of maximum power transfer has been also estimated., submitted to Annals of Physics

High-speed low-loss micromachined coplanar transmission lines deposited on a polyimide film were fabricated in a GaAs technology. On-wafer measurements of scattering parameters up to 110 GHz show an effecti e permitti ity as low as 1.08. Special attention was also paid to the tapering section between the probing and substrateless regions, taking ad antage of the etching profile. Q 1999 John Wiley & Sons, Inc. Microwave Opt Technol Lett 20: 106]110, 1999.

Experimental evidence is reported on the control of the directionality of guided electromagnetic microwaves by the polarization of the exciting wave. Experiments are conducted using a two-dimensional waveguide made of two parallel aluminum plates. The upper plate, which has a linear array of holes, is externally illuminated by a polarized wave whose incident wavevector is contained within the mirror-symmetry plane defined by the linear array. Surprisingly, the measurements show that the propagation inside the waveguide is highly asymmetrical, and it is controlled by the polarization of the incoming wave. This extraordinary phenomenon is explained in terms of a simple model involving a set of dipoles that are excited at the hole positions. Our finding provides a powerful method to sort different polarizations of a free-space beam to different propagation directions of guided electromagnetic waves., The authors gratefully acknowledge B. Bernardo and A. Vila at Electromagnetic Radiation Group Universitat Politecnica de Valencia for the generous donation of the circular polarization antenna for the experiments. J.S.-D. thanks D. Torrent for useful discussions. Financial support from the Spanish Ministry of Economy and Competitiveness (Grants No. TEC2010-19751, No. TEC2011-28664-C02, and No. Consolider CSD2008-00066) is also acknowledged.

Experimental evidence demonstrating that anomalous localization of waves can be induced in a controllable manner is reported. A microwave waveguide with dielectric slabs randomly placed is used to confirm the presence of anomalous localization. If the random spacing between slabs follows a distribution with a power-law tail (L\'evy-type distribution), unconventional properties in the microwave-transmission fluctuations take place revealing the presence of anomalous localization. We study both theoretically and experimentally the complete distribution of the transmission through random waveguides characterized by $\alpha=1/2$ ("L\'evy waveguides") and $\alpha=3/4$, $\alpha$ being the exponent of the power-law tail of the L\'evy-type distribution. As we show, the transmission distributions are determined by only two parameters, both of them experimentally accessible. Effects of anomalous localization on the transmission are compared with those from the standard Anderson localization., Comment: 5 pages, 4 figures. Revised version as published"

Metamaterial shells based on radially dependent anisotropic parameters are analyzed in view of achieving different types of applications. The theoretical proposal is reviewed together with some possible applications of these resonant structures. Position sensors, energy harvesters or wireless energy transfer systems are briefly presented.

Based on the concepts of artificially microstructured materials, i.e. metamaterials, we present here the first practical realization of a radial wave crystal. This type of device was introduced as a theoretical proposal in the field of acoustics, and can be briefly defined as a structured medium with radial symmetry, where the constitutive parameters are invariant under radial geometrical translations. Our practical demonstration is realized in the electromagnetic microwave spectrum, because of the equivalence between the wave problems in both fields. A device has been designed, fabricated and experimentally characterized. It is able to perform beam shaping of punctual wave sources, and also to sense position and frequency of external radiators. Owing to the flexibility offered by the design concept, other possible applications are discussed., This work was supported in part by the Spanish Ministry of Science and Innovation under Grants TEC 2010-19751 and CSD2008-00066 (Consolider program) and by the U.S. Office of Naval Research under Grant N000140910554.

To determine clinical characteristics of the population with Fournier's necrosis at Hospital Universitario del Valle (HUV) in Cali during the period 2003-2008.We performed a retrospective review of patients with the diagnosis of Fournier's necrosis at HUV during the period 2003-2008. We collected information on age,personal history, duration of illness, hospitalization, surgeries performed, time to surgical treatment, isolated germs, and mortality. Univariate descriptive analysis was performed in STATA v 10.1.42 patients with mean age 51 years and 12 days mean disease duration. 26% had diabetes mellitus and 21.4% urethral trauma before admission. Average time to surgical debridement was 41.4 hours. 62% required suprapubic cystostomy, 14.3% derivative colostomy, 9.5% and 2.4% orchiectomy and penectomy respectively. The average hospital stay was 23 days and 12% required ICU care. Scrotal cultures were positive in 59.5%: 64% a single germ and 36% polymicrobial. Reported mortality was 17%.Fournier's necrosis is a life-threatening clinical entity in patients with multiple comorbidities requiring multiple interventions. Broad-spectrum antimicrobial therapy, aggressive debridement of necrotic tissue and comprehensive management of these patients are the mainstays in the treatment of these severely ill patients.

We analyze the properties of acoustic and electromagnetic metamaterials with anisotropic constitutive parameters. Particularly, we analyze the so-called Radial Wave Crystals, which are radially periodic structures verifying the Bloch theorem. This type of crystals can be designed and implemented in acoustics as well as in electromagnetism by using anisotropic metamaterials. In acoustics, we have previously predicted that they can be employed as acoustic cavities with huge quality factors and also like dynamically driven antennas. Similar functionalities are here proven in the electromagnetic domain with, in particular, an analysis of the functionality of practical devices operating in the microwave regime. Starting from our recent works on anisotropic structures and their comparison in both application fields, we present a complete discussion concerning their properties in acoustics and electromagnetics.

The previous publications (Minano et al, 2011) have shown that using a Spherical Geodesic Waveguide (SGW), it can be achieved the super-resolution up to λ /500 close to a set of discrete frequencies. These frequencies are directly connected with the well-known Schumann resonance frequencies of spherical symmetric systems. However, the Spherical Geodesic Waveguide (SGW) has been presented as an ideal system, in which the technological obstacles or manufacturing feasibility and their influence on final results were not taken into account. In order to prove the concept of superresolution experimentally, the Spherical Geodesic Waveguide is modified according to the manufacturing requirements and technological limitations. Each manufacturing process imposes some imperfections which can affect the experimental results. Here, we analyze the influence of the manufacturing limitations on the super-resolution properties of the SGW. Beside the theoretical work, herein, there has been presented the experimental results, as well.

Anisotropic characteristics of cylindrically corrugated microstructures are analyzed in terms of their acoustic and electromagnetic (EM) behavior paying special attention to their differences and similarities. A simple analytical model has been developed using effective medium theory to understand the anisotropic features of both types of waves in terms of radial and angular components of the wave propagation velocity. The anisotropic constituent parameters have been obtained by measuring the resonances of cylindrical cavities, as well as from numerical simulations. This permits one to characterize propagation of acoustic and EM waves and to compare the fundamental anisotropic features generated by the corrugated effective medium. Anisotropic coefficients match closely in both physics fields but other relevant parameters show significant differences in the behavior of both types of waves. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft., The authors acknowledge financial support from the Spanish MICINN (TEC 2010-19751 and Consolider CSD2008-00066) and from the US Office of Naval Research (N000140910554). DT also acknowledges support from the program 'Campus de Excelencia Internacional 2010 UPV'.

This letter presents a tunable bandwidth bandpass filter based on varactor-loaded metamaterial coplanar waveguide (CPW) lines. The CPW lines are based on series gaps and split-ring resonators. The varactors are reverse-biased semiconductor diodes connected between both sides of each series gap. This configuration, directly inspired from the so-called metamaterial technology, takes advantage of the high dispersion of the loaded transmission line. Therefore, strong permittivity and permeability responses induced by means of the resonators are obtained. A single varactor-loaded transmission line is first analyzed. Then, a third-order tunable filter with fractional bandwidth tuning range from 5.8% to 21.5% is experimentally assessed. The proposed filters can be used in several practical applications such as multichannel wireless and satellite communication systems, where reconfigurable devices are often required., This work was supported in part by the Centre National d'Etudes Spatiales (CNES), the Ministerio de Ciencia e Innovacion, Spanish Government under Research Project TEC2010-21520-C04, and the Autonomous Government of Castilla-La Mancha under Research Projects PPII10-0027-1277 and TC20112325.

[EN] We present a theoretical and experimental study of the effective permittivity of a photonic crystal (PC) made of parallel dielectric rods in the long-wavelength limit. Using the plane-wave expansion method we derive an analytical expression for the imaginary part of the dielectric tensor. Angular dependence of the dissipative part of permittivity turns out to be more complicated than that for the real part. In particular, it exhibits stronger anisotropy for a PC with rectangular unit cell. Theoretical and numerical results are compared to the experimental measurements of microwave reflection and transmission through a PC fabricated from low-loss alumina rods. A good agreement between the theory and experiment was obtained in the limit where the effective medium approximation is valid. © 2011 Elsevier B.V., This work was supported by the Ministerio de Ciencia e Innovación of Spain under contracts TEC 2007-67239, TEC 2010-19751 and CONSOLIDER CSD2008-00066, by the US Department of Energy through the Grant No. DE-FG02-06ER46312, and by the Office of Naval Research through the Grant No. 000140910554. L.G. acknowledges the support by CONACyT (Mexico) and A.K. acknowledges the support by the Ministerio de Educación of Spain Contract No. SAB2009-00009. Authors thank F. Cervera for technical help.

The main objective of this study was to describe the clinical characteristics of patients diagnosed with penile fracture in the Hospital Universitario del Valle (Cali, Colombia).A descriptive study, reviewing all the medical records of patients diagnosed with penile fracture from January 2001 to December 2008 at Hospital Universitario del Valle (.HUV).in Cali. It took into account variables related to urological history, etiology, diagnosis, the surgical treatment and follow-up. Univariate analysis was performed with the statistical program STATA v. 10.1There were 18 cases of penile fracture with an average age of 30 years. 11 patients (.61%). had episodes related to intercourse. Patients presented swelling, pain and popping or cracking sound. The diagnosis was done by history and physical examination in 100%. Surgery was performed with a subcoronal incision in most of the patients. The right corpus cavernosum was frequently injured and corrected with absorbable suture. The patients had an average of 1.5 days of postoperative hospital stay.Penile fracture is an entity the diagnosis of which is straightforward and can be reliable by history and physical examination. Surgical repair is the treatment of choice preventing complications, allowing the patient to return to satisfactory sexual life.

A technique for the automated generation of the layout of microstrip lines loaded with complementary split ring resonators (CSRRs) is proposed. This synthesis strategy presents a great practical interest, due to the reduction in terms of computational efforts, that is achieved without any significant lack of accuracy in the final solution. The application makes use of an aggressive space mapping (ASM) algorithm based on a constrained Broyden-based input approach. In this case, the parameter extraction (PE) does not require of any optimization, since the circuital parameters of the metamaterial transmission line can be determined following a straightfordward method.

OBJETIVO: El objetivo principal del presente estudio fue describir las caracteristicas clinicas de los pacientes con diagnostico de fractura de pene en el Hospital Universitario del Valle (Cali, Colombia). METODOS: Se realizo un estudio descriptivo, en el que se revisaron todas las historias clinicas de los pacientes con diagnostico de fractura de pene entre enero de 2001 a diciembre de 2008 en el Hospital Universitario del Valle (HUV) en la ciudad de Cali. Se tuvieron en cuenta variables relacionadas con los antecedentes urologicos, la etiologia, el diagnostico de la fractura, el procedimiento quirurgico y el seguimiento. Se realizo un analisis univariado con el programa estadistico STATA v. 10.1. RESULTADOS: Se encontraron 18 casos de fractura de pene con un promedio de edad de 30 anos. 11 pacientes (61%) presentaron el episodio secundario a la relacion sexual. Se presento edema, dolor y chasquido mas frecuentemente. El diagnostico fue clinico en el 100% de los casos. El abordaje quirurgico se realizo con una incision circunferencial en la mayoria de los pacientes. El cuerpo cavernoso derecho fue el mas frecuentemente lesionado y en la mayoria de los casos la lesion fue corregida con una sutura absorbible de forma continua. Los pacientes tuvieron una hospitalizacion posquirurgica en promedio de 1.5 dias. CONCLUSIONES: La fractura de pene es una entidad cuyo diagnostico es clinico, debe realizarse de forma precoz, y la reparacion quirurgica es el tratamiento de eleccion para evitar complicaciones y permitir que el paciente retorne a su actividad sexual satisfactoria de manera temprana.

A 2% bandpass filter with an out-of-band rejection in excess of 30 dB was demonstrated experimentally for operation in the C-band (central frequency at 4.5 GHz). Narrow bandwidth and high rejection were achieved by cascading three double split-ring resonators (SRRs) magnetically coupled to a coplanar waveguide (CPW) and three pairs of shunt wires between the central strip and the ground metal layers. This configuration, directly inspired from the so-called metamaterial technology, takes advantage of the high dispersion of the loaded transmission line, induced by a negative magnetic response via the resonators, and of a negative permittivity effect via the shunt wires. The optimization of: 1) the symmetry; 2) the out-of-band rejection; and 3) the fractional bandwidth was carried out in two stages, i.e., by engineering the plasma frequencies of the electrical and magnetic systems and by tapering the tightly coupled cascaded unit cells in order to achieve an overlap of their individual responses.

Ferromagnetic microwires are investigated as fundamental components to generate metamaterials with double negative parameters. Electric and magnetic responses are, respectively, based on the finite conductivity and ferromagnetic resonance of the wires that in turn depend on their chemical composition. Tuning properties of samples are investigated in terms of the composition of the alloy and the applied magnetic field. The samples are measured and simulated in a waveguide environment for a large microwave frequency range. Numerical modeling supports the experimental results and helps to understand the physics involved in the transmission phenomena. Radius and conductivity of the wires are pointed out as the most critical parameters to generate a double negative response in terms of permittivity and permeability.

In this letter, the design and comparative study of metamaterial-inspired bandpass filters operating at G-band (150 GHz) is presented. To this aim, filters based on split ring resonators (SRRs) and complementary SRRs are studied and compared on a scale compliant with MMIC technology. Technological issues impose severe constraints to the design of this type of devices. Specifically, the filter selectivity concern is addressed as a trade-off between the acceptable insertion losses in the transmitted band and the achievable bandwidth. The addition of series gaps to previous unit cell configurations and suspended membrane structures are introduced to overcome these limitations, thus presenting improved upper band edges and rejection characteristics. In this context, the extension of metamaterial-based filtering structures to higher frequencies and notably at millimeter waves is still lacking. Therefore, we present here the first contribution in this field by addressing the possibility to fabricate an ultra narrow bandpass filter for space applications. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 1868–1872, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25300

International audience; We have analyzed and characterized a terahertz stacked holes array over a broad transmission bandwidth. In this context, we identify the key contributions of the surface plasmon modes related to the periodicity of array, and of the subcut off transmission through the holes responsible of a ground left-handed dispersion branch. The experimental verification of a multimode electromagnetic behavior is performed by time domain spectroscopy, with a complementary assessment by full-wave analysis. A circuitlike approach appears suitable for the understanding of a zero-gap transition between the left- and right-handed characteristics, opening the way of nonvanishing group velocity in a near-zero index propagation medium. Such a balanced composite operation, pointed out over the past in the dual element transmission line approaches, is thus generalized for a stacked subwavelength holes array, whose operation can be compared to the one of the so-called fishnet structures.

The first approach towards the automatic layout generation of resonant-type metamaterial transmission lines by using space mapping optimisation is reported. Specifically, the so-called aggressive space mapping (ASM) technique is applied for synthesising microstrip lines loaded with complementary split ring resonators (CSRRs). From a certain set of elements of the circuit model of the unit cell of such lines (which is typically derived from system specifications), the topology (layout) of the CSRR-loaded microstrip line, providing the same electromagnetic response as the circuit model (within certain error limits), is generated automatically. This synthesis technique is of paramount importance for the design of metamaterial-based (or inspired) circuits implemented by means of electrically small resonators such as CSRRs and SRRs. Although the reported technique is applied here to the synthesis of a negative permittivity structure (CSRR-loaded line), the basics towards the extension of the technique to other artificial transmission lines are clearly established., This work has been supported by MEC (Spain) through the projects TEC2007-68013-C02 METAINNOVA and TEC2007-67630-C03 CABESERES and by MCI (Spain) through the project EMET CSD2008-00066 of the CONSOLIDER Ingenio 2010 Program. The authors especially thank Generalitat de Catalunya for funding CIMITEC and for supporting GEMMA through the project 2009SGR-421. The Ministerio de Education (Spain) has given an FPU grant to J.S. with reference AP2008-04707.

To determine the prevalence of abnormal coagulation tests in patients who undergo transrectal prostate biopsy.A cross-sectional study was performed at Hospital Universitario del Valle (HUV) between 1 June and 31 December 2008. Variables collected included age, PSA value, PT (prothrombin time), PTT (partial thromboplastin time) and INR (international normalized ratio) values and the presence of abnormalities in each of the haematological variables. There are no real normal or maximum acceptable values in clinical practice; however, the values described by some authors and different clinical practice protocols serve as a guide.The average age was 70 years, the median PSA was 28, the partial thromboplastin time was altered in 2.3% of patients, and INR was abnormal in 3.4% of patients (cut-off point 1.5). There were no changes in PT or INR values (cut-off point 2.0).The prevalence of abnormal coagulation tests is low even when there are no clear cut-off points in worldwide literature that would determine abnormality.

Resumen Objetivo Determinar la prevalencia de las alteraciones en las pruebas de coagulacion en pacientes sometidos a biopsia transrectal de la prostata. Material y metodos Se realizo un estudio de corte transversal en el hospital universitario del valle (HUV) entre el 1 de junio y el 31 de diciembre de 2008. Se recolectaron variables tales como edad, valor del antigeno prostatico especifico (PSA), valor del PT (tiempo de protrombina), valor del PTT (tiempo parcial de tromboplastina), valor de INR (relacion internacional normalizada) y la presencia de anormalidad en cada una de las variables hematologicas. No existen valores normales o maximos aceptables en realidad en la practica clinica; sin embargo, se toman como base los valores descritos por algunos autores y diferentes protocolos de practica clinica. Resultados El promedio de edad fue 70 anos, la mediana del PSA fue 28, el PTT fue alterado en el 2,3%, el INR fue anormal en el 3,4% (punto de corte, 1,5). No se encontraron alteraciones en los valores de PT ni en el INR (punto de corte, 2,0). Conclusiones La prevalencia de alteraciones en las pruebas de coagulacion es baja, aun cuando no existen puntos de corte claros en la literatura cientifica mundial para determinar anormalidad.

International audience; We report on the theoretical and experimental analysis of Omega-type metamaterials operating in X and Ku-bands. The prototypes are fabricated on the basis of metal waveguide technologies (hollow and TEM parallel plate) loaded with printed boards of interconnected Omega-shaped motifs. This interconnection of particles in the transverse direction leads to a broad left-handed band. Moreover, it is shown that such structures can be designed for a continuous negative-zero-positive index dispersion. This balanced composite behavior, so far known for periodically loaded transmission lines is verified experimentally with left- and right-handed dispersion branches extending from 8 to 12 and 12 to 16 GHz respectively. This zero-gap capability is explained on the basis of effective parameters retrieval.

International audience; Negative-zero-positive index refraction was demonstrated numerically on the basis of full-wave analysis of a microstructured omega-type array and experimentally via angle resolved transmission measurement of a prism-type prototype. The experimental results are interpreted in terms of characteristic impedance and refractive index retrieved by a Fresnel inversion technique. The possibility to balance the dispersion characteristics with a negative-zero-positive index is demonstrated over X - and Ku -bands.

International audience; We numerically and experimentally investigated the electromagnetic properties of split ring resonator arrays excited under normal and oblique incidence angles and aimed at operating from the microwave to the infrared spectral region. Through fullwave EM analysis, the electromagnetic response is demonstrated in the metamaterial regime (inclusion rather than periodicity effect) responsible for high rejection in the TE and TM modes transmission spectra which are measured via Vectorial Network Analysis (VNA) at microwave and by Fourier transform spectroscopy (FTIR) in optics.

The advantages afforded by the symmetrical C(V) characteristics of Heterostructure Barrier Varactor (HBV) diodes for the fabrication of nonlinear metamaterials are investigated numerically. The studies are conducted by means of full-wave numerical modelling along with circuit analysis. It is believed that the HBV technologies can replace the conventional Schottky diode not only in up and down frequency conversion left-handed devices, but also by bringing new functionality in terms of space filtering for unbiased devices. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 474–479, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23122

For the first time, an automated design procedure based on space mapping techniques is developed for the EM-based optimization of left-handed coplanar waveguide (CPW) filters based on split ring resonators (SRRs). Our design procedure is based on a constrained Broyden-based input multistage space mapping strategy, using a statistical approach to parameter extraction (PE). Pre-conditioning of the coarse model design parameters is used at each PE iteration, imposed by the severely bounded region of validity of the equivalent circuit model. The space mapping algorithm effectively aligns equivalent circuit responses with simulated results provided by full-wave electromagnetic simulation tools. Our method is illustrated by the EM-based design of a CPW bandpass filter with 3 SRRs.

This paper reports on the design and experimental characterization of evanescent waveguides loaded with split ring resonators SRRs supporting enhanced backward wave propagation. With respect to previous negative refractive index devices based on metallic waveguides, the use of a direct coaxial probe excitation inside an evanescent waveguide drastically improves transmission and reflection characteristics of the periodic structure. Moreover, the addition of metallic windows interleaved between consecutive resonators offers an extra degree of freedom in order to control interresonator couplings, and hence, device parameters like overall transmission, reflection, and bandwidth of the backward wave pass band. A numerical and experimental analysis of different structures overcoming the high loss issue of previously published results is detailed. An experimental validation of the proposed enhancements is done for periodic structures, where no individual tuning of the resonator sections is performed. The proposed technology mainly offers the advantage of miniaturization, and it could be combined in a further step with standard design techniques to provide frequency selective devices. Ministerio de Educación y Ciencia, Gobierno de España-TEC-2004-04313-C02-01 y TEC-2004-04249.C02-02 Generalitat Valenciana-ACOMP06/013 y GVA/2007/215