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El objetivo del presente estudio fue validar una metodología sencilla de estimación de los umbrales ventilatorios basada en la potencia aeróbica máxima alcanzada en un test incremental máximo. Para ello, el estudio se dividió en dos fases. En la primera fase, 85 sujetos realizaron una prueba de esfuerzo incremental en cicloergómetro. Se determinó el porcentaje de la potencia máxima alcanzada en el test donde se calcularon los umbrales ventilatorios. En la segunda fase de este estudio se realizó una validación transversal. Para lo cual, 11 sujetos que no habían participado en la primera fase realizaron un test incremental para conocer su potencia aeróbica máxima. Posteriormente los sujetos realizaron tres pruebas de máximo estado estable de lactato. Las intensidades a las que se realizaron estas pruebas se determinaron teniendo en cuenta el porcentaje de la potencia máxima al que aparecieron los umbrales en la primera fase del estudio. Así, una prueba se realizó a la potencia estimada del umbral aeróbico, otra a la potencia estimada del umbral anaeróbico, y una última un 10% por debajo de la potencia del umbral anaeróbico. Los resultados de este estudio mostraron un estado estable de lactato en las pruebas realizadas a la intensidad del umbral aeróbico y la prueba realizada un 10% por debajo del umbral anaeróbico. En conclusión, la utilización de un porcentaje de la potencia máxima alcanzada en una prueba incremental puede ser utilizado para estimar los umbrales ventilatorios de manera sencilla. Nuestros resultados indican que en torno al 50% y 70% de la potencia máxima pueden situarse los umbrales ventilatorios aeróbico y anaeróbico, respectivamente

Riverbank filtration (RBF) is a surface water filtration method for drinking water through the banks and bed of a river, using extraction wells located near the water body in order to ensure direct aquifer recharge. As the surface water travels through the sediments, contaminants, such as suspended and colloidal solids and pathogenic microorganisms, are removed. Apart from water quality improvement, RBF has the advantage of reducing peak concentrations which commonly pass through a river. RBF has been widely used in Europe, USA and, nowadays, in some Asian countries (e.g., South Korea, India, China). Latin-American and specifically Colombian river basins, have been suffering a continuous deterioration, leading to high suspended sediment loads being transported by the rivers. The RBF technology has not been proven yet in highly turbid waters, in which the excessive transport of suspended sediments threatens sustainable operation. Clogging of both the riverbed and deeper aquifer may increase flow resistance, reducing water revenues over the course of time. To assess the feasibility of RBF for highly turbid river waters in Colombia, a combination of field and laboratory research was conducted – both in the Netherlands and Colombia. In Colombia, the studies were done at the Cinara institute's Research and Technology Transfer (R&TT) Station for drinking water and at the Fluid Mechanics lab. The station is located at the Northeast of Cali, Colombia, and was built at the premises of the main water treatment plant of Cali, Puerto Mallarino. In the Netherlands, the laboratory work was done at the Delft University of Technology, running infiltration column experiments at the Sanitary Engineering lab and the flume experiments at the Fluid Mechanics lab...

INTRODUCCIÓN: La exéresis percutánea de lesiones benignas de mama asistida por vacío (ultrasound vacuum-assisted excision – siglas en inglés US-VAE) es una alternativa terapéutica reconocida a la cirugía. Sin embargo, existe gran variabilidad de resultados publicados de efectividad. No están establecidos criterios predictores de resección completa, ni un método que permita evaluar el aprendizaje ni el desempeño de la técnica. El objetivo es esta tesis es evaluar de forma prospectiva esta técnica tanto en eficacia, complicaciones, aprendizaje y costes. MATERIALES Y MÉTODOS Se evaluaron 152 US-VAE de lesiones benignas en 143 pacientes en el Hospital Vall d’Hebron, Barcelona. Se realizó seguimiento ecográfico y clínico a los 6 meses valorando la lesión residual y los síntomas clínicos. Se analizaron efectividad y seguridad de la técnica según variables de interés, así como posibles predictores de resección completa. Se utilizó el modelo de gráficas CUSUM para valoración de curvas de aprendizaje de la técnica. Finalmente, se determinó el costo directo de la US-VAE. RESULTADOS: En 138 (90.8%) de las pacientes se obtuvo resección completa, con un 7.9% de hematomas a las 24 horas. Se realizó seguimiento a los 6 meses post-VAE en 143 (94%) de los procedimientos y se confirmó resección completa en (72%), con resolución de síntomas y palpación en 88.1% de los casos. La efectividad a los 6 meses, el control clínico y el desarrollo de hematoma varían de forma significativa e inversamente proporcional en función del tamaño y volumen de la lesión. El punto de corte de diámetro para predecir residuo ecográfico a 6 meses es 20mm, con una probabilidad del 84.5% de no tener lesión residual en lesiones con volumen, INTRODUCTION: The ultrasound vacuum-assisted excision (US-VAE) of benign breast lesions is a recognized therapeutic alternative to surgery. However, there is great variability of published results regarding its effectiveness. Predictive criteria for complete resection, or a method allowing evaluation of learning or performance of this technique have not been established. The objective of this thesis is to evaluate the efficacy, complications, learning process and costs of this technique prospectively. MATERIALS AND METHODS: 152 US-VAEs of benign lesions in 143 patients were carried out at Vall d'Hebron Hospital, Barcelona. Sonographic and clinical follow-up were performed at 6 months assessing residual lesion and clinical symptoms. Effectiveness and safety of this technique were analyzed according to variables of interest, as well as possible variables predicting complete resection. The CUSUM model was used to evaluate learning curves. Finally, the direct cost of US-VAE was determined. RESULTS: Complete resection was observed in 138 (90.8%) of patients and 7.9% presented hematomas 24 hours later. Six months after VAE, follow-up was completed for 143 (94%) of cases and complete resection was observed in 72%, with disappearance of symptoms and palpation in 88.1% of cases. At six months, the effectiveness, clinical control and development of hematoma varied significantly in and inversely proportional fashion according to the size and volume of the lesion. The size threshold for predicting sonographic residue at six months is approximately 20mm, with an 84.5% probability of leaving no residues in lesions

A W-band radiometer with intermediate frequency down-conversion for radio astronomy applications is presented. The receiver consists of two W-band low noise amplifiers followed by a subharmonic mixer, intermediate frequency amplification and a square-law detector. The performance of the receiver subsystems is characterized experimentally. The receiver works in the 82 to 96 GHz frequency band, and using a local oscillator of 27.1 GHz with 8 dBm of available power, it exhibits an overall conversion gain around 48 dB, a noise figure of 4.5 dB, and an effective bandwidth of 10 GHz. The receiver performance is characterized when a broadband noise input signal is applied. The radiometer characteristic has been obtained working as a total power radiometer and as a Dicke radiometer when an optical chopper is used to modulate the incoming signal. Este trabajo ha sido financiado por el Ministerio de Economía y Competitividad bajo el programa CONSOLIDER-INGENIO 2010 referencia CSD2010-00064, Red de excelencia CONSOLIDER-SPATEK y Universidad de Cantabria, Doctorado Industrial 2014 referencia 12.DI05.648.

The use of THz frequencies, particularly W and G band allows reaching higher resolution and deeper penetration in emerging applications like imaging, sensing, etc. The development of those new applications lays on reliable technologies, background of expertise and know-how. The CDS2008-00068 TERASENSE CONSOLIDER project has given the opportunity to extent upwards in frequency the previous background of the microwaves research group partners. This article summarizes the developments of the TERASENSE work package “THz Device Technology Laboratory”. This work was supported by the Spanish Ministerio de Ciencia e Innovación through the CONSOLIDER-INGENIO 2010 program reference CSD2008-00068 TERASENSE.

The most popular use of the Pura Raza Espanol horse in sport is for dres- ~ sage competitions. Tests on young sport horses were first established in 2004 in Spain to collect data for the genetic evaluation of this breed’s suitability for dressage. The aim of this study was to compare eight different models to find out the most appropriate way to include the rider in the genetic evaluation of dressage. A progressive removal of systematic effects from model was also analysed. A total of 8867 performance records collected between 2004 and 2011 from 1234 horses aged between 4 and 6 years old were used. The final score in the dressage test was used as the performance trait. The pedigree matrix contained 8487 individuals. A BLUP animal model was applied using a Bayesian approach with TM software. The horse’s age, gender, travelling time, training level, stud of birth and event were included as systematic effects in all the models. Apart from the animal and residual effects that were present in all models, different models were compared combining random effects such as the rider, match (i.e. rider–horse interaction) and permanent environmental effects. A cross-validation approach was used to evaluate the models’ prediction ability. The best model included the permanent environmental, rider and match random effects. As far as systematic effects are concerned, the event or the stud of birth was essential effects needed to fit the data.

Introducción. Un tercio de los carcinomas colorrectales se presentan en pacientes jóvenes por debajo de los 50 años de edad, el 15% de éstos se relacionan con inestabilidad microsatelital debida a mutaciones en la línea germinal de los genes relacionados con la reparación del ADN. La otra proporción de carcinomas colorrectales tienen alteraciones epigenéticas por hipermetilación e inactivación epigenética del sitio promotor del gen hMLH1, en donde la mutación del gen BRAFv600 es un evento característico. La inmunohistoquímica ayuda a clasificar este tipo de carcinomas con una especificidad del 100% y un 92% de sensibilidad. Objetivos. Demostrar si la edad es un factor de riesgo para la ausencia de expresión de proteínas relacionadas con la reparación del ADN (MMR) y mutaciones del gen BRAF en nuestra población y compararlos con sus hallazgos histopatológicos. Material y Métodos. Se realizaron estudios de Inmunohistoquímica para MLH1 y MSH2 y RT PCR para BRAFv600 y secuenciación en el tejido obtenido de 57 pacientes menores de 50 años. Se documentaron la edad, sexo, tipo histológico, profundidad de la invasión y la cantidad de ganglios linfáticos disecados y con enfermedad metastásica, entre estos pacientes se buscaron además aquellos que reunieran criterios de Bethesda para poderlos clasificar como probable síndrome de Lynch. Asimismo, se usaron 48 pacientes mayores de 50 años como grupo control. En el análisis estadístico se utilizaron las pruebas estadísticas de ANOVA, X2, y correlación de Spearman. Resultados. La ausencia de expresión de proteínas relacionadas con MMR fue más frecuente en pacientes con CCR menores de 50 años. No encontramos mutaciones en ninguno de los dos grupos. Las variedades Medular y Mucinosa fueron más frecuentes en los pacientes jóvenes,mientras que la intestinal fue más frecuente en el grupo de adultos mayores (p=0.0008). No hubo diferencias significativas relacionadas con el estadio patológico de los grupos. Identificamos 15 pacientes jóvenes con CCR con uno o dos criterios de Bethesda, sea por alteración en expresión de proteínas relacionadas con MMR, historia familiar de CCR u otros tumores relacionados con síndrome de Lynch. Conclusiones. Se demostró en este trabajo que efectivamente la ausencia de expresión de proteínas relacionadas con la reparación de ADN es más frecuente en pacientes jóvenes. No se encontraron mutaciones del gen BRAFv600 en ninguno de los dos grupos.Introducción. Un tercio de los carcinomas colorrectales se presentan en pacientes jóvenes por debajo de los 50 años de edad, el 15% de éstos se relacionan con inestabilidad microsatelital debida a mutaciones en la línea germinal de los genes relacionados con la reparación del ADN. La otra proporción de carcinomas colorrectales tienen alteraciones epigenéticas por hipermetilación e inactivación epigenética del sitio promotor del gen hMLH1, en donde la mutación del gen BRAFv600 es un evento característico. La inmunohistoquímica ayuda a clasificar este tipo de carcinomas con una especificidad del 100% y un 92% de sensibilidad. Objetivos. Demostrar si la edad es un factor de riesgo para la ausencia de expresión de proteínas relacionadas con la reparación del ADN (MMR) y mutaciones del gen BRAF en nuestra población y compararlos con sus hallazgos histopatológicos. Material y Métodos. Se realizaron estudios de Inmunohistoquímica para MLH1 y MSH2 y RT PCR para BRAFv600 y secuenciación en el tejido obtenido de 57 pacientes menores de 50 años. Se documentaron la edad, sexo, tipo histológico, profundidad de la invasión y la cantidad de ganglios linfáticos disecados y con enfermedad metastásica, entre estos pacientes se buscaron además aquellos que reunieran criterios de Bethesda para poderlos clasificar como probable síndrome de Lynch. Asimismo, se usaron 48 pacientes mayores de 50 años como grupo control. En el análisis estadístico se utilizaron las pruebas estadísticas de ANOVA, X2, y correlación de Spearman. Resultados. La ausencia de expresión de proteínas relacionadas con MMR fue más frecuente en pacientes con CCR menores de 50 años. No encontramos mutaciones en ninguno de los dos grupos. Las variedades Medular y Mucinosa fueron más frecuentes en los pacientes jóvenes,mientras que la intestinal fue más frecuente en el grupo de adultos mayores (p=0.0008). No hubo diferencias significativas relacionadas con el estadio patológico de los grupos. Identificamos 15 pacientes jóvenes con CCR con uno o dos criterios de Bethesda, sea por alteración en expresión de proteínas relacionadas con MMR, historia familiar de CCR u otros tumores relacionados con síndrome de Lynch. Conclusiones. Se demostró en este trabajo que efectivamente la ausencia de expresión de proteínas relacionadas con la reparación de ADN es más frecuente en pacientes jóvenes. No se encontraron mutaciones del gen BRAFv600 en ninguno de los dos grupos.Se describe de forma novel el primer grupo de pacientes con probable síndrome de Lynch mediante criterios de Bethesda. [ABSTRACT]Background. A third of colorectal carcinomas (CRC) affects patients under 50 years. Fifteen percent of CRC cases with microsatellite instability are due to inherited germ-line mutations in DNA mismatch repair genes. The rest have an epigenetic hypermethylation of the hMLH1 gene promoter in whom the BRAFv600E mutation is a common hallmark. Immunohistochemistry helps classifying colorectal cancers with 100% specificity and 92% sensitivity. Aims. To determine if age is a risk factor for defective MMR protein expression and BRAF mutations in our population and to compare these results with the histopathologic tumor features. Materials and methods. Immunohistochemistry for MLH1 and MSH2 and RT-PCR BRAFv600 mutation was performed on tissue specimens from 57 patients < 50 years of age by Real time PCR and sequentiation. Data on age, gender, tumor location, histologic type, depth of infiltration, and the presence of metastatic lymph nodes were collected, once we collect this that we among the young individuals with colorectal cancer if between them it will fit the Bethesda criteria in order to classify them like a probable Lynch syndrome. Forty eight patients >50 years of age were used as a control group. A statistical analysis using ANOVA, X2, and Spearman´s rho test were performed. Results. Absent MMR protein expression was more prevalent in patients under 50 years. No BRAF mutations were detected in either group. Medullary and mucinous types were more prevalent among young patients, while intestinal type was more frequent in older patients (P=0.0008). No differences were found regarding clinicopathological stages between groups. We found a group of 15 patients among young individuals with colorectal carcinoma with one o more of two Bethesda criteria either by alteration of MMR proteins expression, family history of colorectal carcinoma or other tumors realted to Lynch syndrome. Conclusions. We found an association between young age and defective MMR expression. No v600E BRAF mutations were detected in either group. We describe also the first group of young individuals that fit in probable Lynch Syndrome by the Bethesda criteria.

In this paper, we report the design of a waveguideto- microstrip transition at W band as well as the technical considerations to take into account during the design and fabrication. In the same way, a double back-to-back waveguideto- microstrip transition has been designed and fabricated to be measured with a PNA Millimeter-Wave Network Analyzer. This structure will serve to assemble MMICs at these high frequencies. A comparison between an electromagnetic simulation and the measurements obtained in the laboratory is shown. Moreover, we show a more accuracy simulation taking into account the real dimensions and the real position of the microstrip lines used within the transition. It can be seen how this realistic simulation is more similar to the obtained measurements.

Characterization and modelling of devices, in particular diodes, in W band becomes a complex task due to the difficulties to de-embed parasitic effects of the access elements. We present a CAD model developed for two CPW-Microstrip transitions connected with a bond wire. It will be used to deembed device measurements from empirical data results when using a commercial calibration substrate with measurement reference planes at the probe tips, which not includes CPW to microstrip transitions in the standards neither wire bonds. The Interface Model has been verified by comparing measurements and two types of simulations (3D EM and circuital physicallybased) of the CPW_Micorstrip- bond_wire-CPW_Microstrip.

In this article a review is carried out of how technological aspects are affecting the system configuration of a sub-millimeterwave receiver for imaging applications. Throughout the discussion we will emphasize the role that the Schottky diode plays in this type of applications.

Different topologies of total power radiometer in W band are presented and compared in terms of effective bandwidth and sensitivity. Both, commercially available and own designed MMICS are considered. A simulation procedure is proposed to emulate in harmonic balance the application of wide bandwidth noise. Technological issues of the implementation are addressed.

Schottky diodes fabricated by the University of Virginia in USA have been subject of intense recent investigation and have emerged as attractive candidates at THz frequencies. Single Schottky diodes have junctions with extremely low junction capacitance, and low series resistance which makes them extremely well-suited for commutating mixer circuits in which ideal switching behaviour is highly desirable. Schottky diodes also offer lower forward voltage compared to an otherwise equivalent p-n junction diode. This permits Schottky diodes to detect lower amplitude signals than a p-n junction. In this paper we describe a procedure to extract the parameters of a high performance THz Schottky diode. Model extraction is done using a combination of dc and small-signal RF measurements. The results show that the proposed method is suitable to determine parameters of diode model with the excellent fit between measured and calculated I-V DC and S-parameter.

In this work, system level modelling and realistic simulation and measurement results of a 31 GHz Back-End Module (BEM) Low-Noise Amplifier (LNA), designed for the QUIJOTE CMB (Q U I JOint TEnerife CMB) experiment radiometer, are reported. The signals received by radiometers can be identified as continuous spectre gaussian white noise signals. This makes necessary time-domain simulation techniques and appropriate models for the realistic analysis of radiometers behaviour. The measured-based modelling of one BEM´s LNA, its simulation in nominal conditions and the measurement of the nonlinear characteristic by using filtered white noise excitation signals, will be shown. Typically, in the LNAs design process the linearity is not taken into account but, as we will see, in the radiometers case, the nature of Gaussian noise excitation signals makes amplifiers to present higher nonlinearity in their characteristics than when using single tone excitation signals. Therefore, in order to analyze the suitability of the LNAs nominal operation, linearity figures of merit have to be obtained, but using realistic excitation signals. In this paper, the LNAs nonlinear characteristics with gaussian noise excitation signals have been obtained.

In this work, system level modelling and realistic simulation and measurement results of a 31 GHz Back-End Module (BEM) Low-Noise Amplifier (LNA), designed for the QUIJOTE CMB (Q U I JOint TEnerife CMB) experiment radiometer, are reported. The signals received by radiometers can be identified as continuous spectre gaussian white noise signals. This makes necessary time-domain simulation techniques and appropriate models for the realistic analysis of radiometers behaviour. The measured-based modelling of one BEM´s LNA, its simulation in nominal conditions and the measurement of the nonlinear characteristic by using filtered white noise excitation signals, will be shown. Typically, in the LNAs design process the linearity is not taken into account but, as we will see, in the radiometers case, the nature of gaussian noise excitation signals makes amplifiers to present higher nonlinearity in their characteristics than when using single tone excitation signals. Therefore, in order to analyze the suitability of the LNAs nominal operation, linearity figures of merit have to be obtained, but using realistic excitation signals. In this paper, the LNAs nonlinear characteristics with gaussian noise excitation signals have been obtained by simulation and measurement.

Soliton oscillators enable the generation of short-time pulses, applicable in sampling of fast signals or as probe signals in radar systems. The soliton oscillator is made up of a feedback loop containing an amplifier stage and a nonlinear transmission line. In this paper, an efficient technique for the harmonic balance design of these oscillators is presented. The bifurcation behavior of this kind of oscillators is analyzed in depth, with a detailed study of their oscillation modes. The sources of non ideality of the soliton-train waveform have also been investigated. The techniques have been applied to a first prototype at 1 GHz with very good agreement with the measured results.

In the reported work, an efficient modelling method is applied to the circuits of the 30 GHz Back End Module of the QUIJOTE experiment radiometer. In particular, efficient models of two LNAs, a band pass filter and a detector has been obtained. These models allow realistic time-domain BEM simulation by using Gaussian noise excitation signals. Simulation results have been reported, showing good agreement with the BEM expected operation. On the other hand, time-domain realistic simulations will provide valuable information about BEM behaviour previously to the receiver definitive implementation.

This work presents a calibration procedure based on the LRL (Line-Reflect-Line) technique which corrects the drift errors of the network analyzer when the calibration process involves several thermal cycles for cooling the different standards taking long time to finish the measurement process in a cryogenic system. This procedure requires to calibrate each time outside the cryostat before measuring the standards and finally to apply a LRL de-embedding routine to obtain the DUT S-parameters. This technique, especially suitable for in-fixture devices in a cryogenic environment, is applied for measuring the S-parameters of an E-pHEMT device operating at 40 K from 0.4 to 3.2 GHz as a starting point for designing an amplifier in this band. Measurements of S-parameters, using the proposed procedure, of this amplifier at 40 K are presented.

The studbook of the Andalusian horse comprising a total of 75,389 individuals (6318 of them classified as Carthusians) was analysed in order to ascertain the genetic history of the breed and, specially, to evaluate its genetic variability and the influence of the Carthusian strain in the breed. Although there is no possible way to identify studs acting as Nucleus in the breed, there is a high concentration of genes and individuals' origin. The effective number of studs producing grandfathers was of 10.6. The equivalent number of founders was 1948.5 individuals (370.5 Carthusians). The effective number of founders was 39.6 and the effective number of ancestors 27. Only 6 ancestors were necessary to explain 50% of the genetic variability of the breed. The average values of inbreeding and average relatedness for the whole Andalusian horse population were, respectively, 8.48% and 12.25%. The same values for the Carthusian strain were higher (9.08% and 13.01%) even thought the generation interval for the strain was larger than that for the whole population (12.43 versus 10.11 years). In any case, inbreeding in Andalusian horse breed seems to have a remote origin and linked to the Carthusian individuals. The total contribution of the Carthusian founders to the populations accounted for up to 87.64% of the population. In turn the Carthusian ancestors explained 80.46% of the genetic variability of the breed. No differentiation was found between Carthusian and non-Carthusian reproductive individuals using genealogical FST (0.000026). It can be concluded that the distinction between Carthusian and non-Carthusian individuals within the Andalusian horse breed does not have genetic support. The unbalanced use of the Carthusian individuals with lower average relatedness values for reproduction is proposed to preserve the genetic variability of the breed. Ministerio de Economía y Competitividad RZ03-011

This communication deals with the implemented assemblies and characterisation test results of several Back End Modules at 44 GHz for the Planck Mission of the European Space Agency (ESA), which are low noise and broadband (20%) receivers having direct conversion to DC. They are parts of the 44 GHz radiometers. In order to perform integration tests, before the integration of Flight Model units, some representative demonstrators have been manufactured and tested. These demonstrators will be integrated in Jodrell Bank Observatory (Manchester, England) with the Front End Modules made there. Main magnitudes tested are effective bandwidth, RF to DC response, noise temperature, linearity, input matching, video bandwidth and knee frequency of low frequency 1/f noise at the output.

The Back End Module at 30 GHz for the Planck mission has been manufactured in its Qualification Model version. Design, integration and main performances are described. Electrical, thermal and vibration tests, already done for space qualification, are summarised. This module consists basically in four identical branches based on broadband low noise amplification, direct detection and video amplification.

Título del congreso: 'El español, lengua del mestizaje y la interculturalidad' Se reflexiona sobre una serie de propuestas para la enseñanza de la lexicogénesis a estudiantes de una LE2. Se trata de hacer hincapié en la necesidad de que el docente se ocupe de facilitar a los estudiantes de otras lenguas y de otras culturas el aprendizaje de los mecanismos de formación de palabras y de creación de nuevas unidades léxicas en español, sin olvidar las llamadas colocaciones léxicas, locuciones y enunciados fraseológicos, que ponen de manifiesto el comportamiento idiosincrásico de la lengua. Madrid ESP

Two Q-band monolithic low noise amplifiers have been designed and characterized. A study about depletion and enhancement mode HEMTs with the same technology has been performed in order to apply these results to the design of the low noise amplifiers. These circuits have been developed for being used in the Back End module of the radiometers in the European Scientific mission Planck, because there are not commercial circuits in this frequency band. The main goals for these amplifiers are low noise with a small DC consumption. A minimum noise figure of 2.8 dB with an associated gain of 23.1 dB at 40.4 GHz has been measured for the E-HEMT MMIC LNA and its DC current consumption was 15.45 mA. The D-HEMT MMIC LNA has a minimum noise figure of 3 dB with an associated gain of 23.2 dB at 42 GHz and 30 mA of DC current consumption.

An approach to heterojunction bipolar transistors (HBT’s) characterization and modeling is presented whit a compact HBT nonlinear circuit model which accounts for the temperature dependence effects. The parameters are extracted from DC and S-parameters measurements. The power characteristics of the device are then predicted using the extracted model without any further optimizations. The model has been implemented in MDS –HP nonlinear simulator. Good fitting is obtained in DC and scattering curves up to 40 GHz. An amplifier designed with the HBT67 transistors is presented. Simulations show good agreement with measurements.

This paper describes the design and assembly of two low noise wideband monolithic Ka-Band amplifiers. The designs are fully monolithic. Philips Microwave Limeil ED02AH process, which employs a 0.2 µm Pseudomorphic-High Electron Mobility Transistor (P-HEMT) was the technology chosen. One amplifier has four stages and the other has three stages. A first stage with inductive source feedback has been used to achieve a low noise performance with reasonable gain and return loss and parallel feedback has been used in the last stages to five an upward slope to the gain. The circuit has been measured in a home made test fixture with ridged waveguide (WR-28) own designed transitions to couple the signal from waveguide to microstrip. A gain greater than 12dB with an average noise of 2.3dB from 28GHz to 36 GHz and a minimum noise figure of 1.8 dB at 29.5 dB was measured for the four stages MMIC amplifier.

This paper describes the design of a resistive monolithic Q-band HEMT mixer for optimum conversion loss and IMD performance. Transistor two-sided harmonic measurements across Vds and Vgs revealed the presence of IMD sweet spots that were used to optimize the conversion loss and IMD behavior of the mixer. Minimum conversion loss of 10 dB was measured in the 40.8-49 GHz RF frequency band, showing a reasonable agreement with simulation results. Mixer single-tone IMD was measured and simulated. The minimum output level at 3fIF was less than -102 dBm for an RF input level of -10 dBm and for a bias point near the predicted sweet spot.

A new non linear model for SiGe HBTs, obtained with extraction techniques from DC and RF measurements is presented. These equivalent circuit based model is able to characterize the device from low frequencies (100 Mhz) up to the millimeter band (40 GHz). Devices modeled have different dimensions of base and emitter contacts. The HBT devices have been fabricated by Daimler Chrysler Research Centre in Ulm (Germany). Experimental non linear test show good agreement with simulated values.

La dislexia es un trastorno del aprendizaje de origen neurobiológico que afecta principalmente a la lecto-escritura. Las personas con dislexia se caracterizan por presentar dificultades a la hora de decodificar los grafemas en fonemas. Estas dificultades, en la mayoría de los casos, van acompañadas de problemas de conducta y emocionales. El 80% de las personas a las que se le diagnostica un trastorno del aprendizaje tienen dislexia, de ahí, la importancia que reside en el conocimiento de este trastorno en todos los ámbitos de la sociedad, pero sobre todo en el aula. El docente y su actuación en el aula son uno de los pilares más importantes para que los niños y adolescentes con dislexia puedan seguir avanzando adecuadamente en su desarrollo estudiantil. El tratamiento de la dislexia en el aula está avanzando mucho en las últimas décadas, pero aún es insuficiente para solventar algunos problemas. Estudios revelan como la causa principal es la escasa formación de algunos docentes en este campo. Dyslexia is a learning disorder of neurobiological origin which especially affects people’s reading and writing skills. Dyslexic people are characterised by their difficulties on decoding the graphemes into morphemes. In most cases, these difficulties are accompanied by behavioural and emotional problems. 80% of the people who are diagnosed with learning disorders are dyslexic. That is the reason why it is so important to know about this disorder in all areas of society, especially in students’ classrooms. The teacher himself and his performance in the classroom are two of the most important supportive factors so that dyslexic kids and adolescents can continue advancing on their student development. The treatment for dyslexia in the classroom has advanced over the past decades, but it is still not effective enough, which means that there are some unsolved problems. Some studies have shown that the main cause for such problems is the poor training of some teachers in this regard. Universidad de Sevilla. Grado en Filología Hispánica

Universidad de Sevilla. Grado en Filología Hispánica

Universidad de Sevilla. Grado Filológica Hispánica

Grado en Ingeniería de Tecnologías de Telecomunicación

Universidad de Sevilla. Grado Filológica Hispánica

Terahertz electromagnetic radiation (from 0.1 THz up op 10 THz) lies in the boundary region between microwave frequencies and infrared and has attracted a great deal of attention in recent years due to all its interesting and remarkable properties. This frequency range is notable for its ability to penetrate non-conductive materials (clothes, paper, cardboard and plastics) with low attenuation, providing a high resolution in imaging techniques, in addition to offering higher resolution than other lower frequencies according to their lower wavelength. A very important aspect to take into account is that, despite being at high frequencies, it is a non-ionizing energy, so it is not harmful to the health of humans. There are numerous applications at Terahertz frequencies, for example making use of their property to be reflected after hitting with metals, arise applications related to people security, such as imaging systems for detection of concealed weapons under clothes. The work presented is this thesis will be focused in the technologies required for this application and its main objective is to acquire the necessary knowledge and experience on Terahertz frequencies to make these technologies available to the national R&D&I system, contributing to its development and evolution. It is remarkable to say that in these high frequencies there are several technology limitations such as: the reduced dimensions of the circuits due to the small wavelength, a very limited number of companies offering components in these bands and limitations in manufacturing and measuring equipment in terms of high cost, higher performance and demanded accuracy. All this restrictions make more complex the development of systems at these frequencies compared to lower frequencies. This work has contributed to extend the previous background of our research group from lower microwave frequencies to reach the W band, starting point of the Terahertz range. Focusing the work in W band which ranges from 75 up to 110 GHz, a comparison between two types of active and passive Imaging systems has been done, analyzing their characteristic parameters. For that, studies have been carried out on the available technologies and several designs of structures and circuits necessary to implement them have been developed. Thus, low noise amplifiers, medium power amplifier, RF power detectors and total power radiometer combining the previous ones have been characterized and integrated in waveguide assemblies. A coupled microstrip band pass filter has been designed and manufactured, as well as different versions of detectors based on a zero bias diode, which has been previously modeled. In addition, it has been modeled the low frequency noise of diodes part of already available detectors in lower frequency, as a preliminary step to afford later the same task in W band detectors. To have a system perspective, beyond the individual components, some basic experiments have been carried out to evaluate reliability of EM simulation procedures of imaging scenarios and its connection to circuit and system simulations. RESUMEN: La radiación electromagnética de Terahercios (desde 0.1 THz hasta 10 THz), que se sitúa en la región limítrofe entre las frecuencias de microondas y el infrarrojo, ha suscitado un gran interés en los últimos años debido a sus interesantes y destacables propiedades. Este rango de frecuencias destaca por su gran capacidad de penetración en materiales no conductores (ropa, papel, cartón y plásticos) con una baja atenuación, obteniendo una alta resolución en técnicas de Imaging, además de ofrecer mayor resolución que otras frecuencias inferiores, de acuerdo con su menor longitud de onda. Un aspecto muy importante a tener en cuenta, es que a pesar de encontrarnos en frecuencias elevadas, se trata de una energía no ionizante, por lo que no es perjudicial para la salud de los seres humanos. Existen numerosas aplicaciones a frecuencias de Terahercios y haciendo uso de la propiedad de reflejar la radiación emitida al chocar con metales, surgen aplicaciones relacionadas con la seguridad de las personas, tales como sistemas de “Imaging” para detección de armas ocultas bajo la ropa. El trabajo presentado es esta tesis se enfocará en las tecnologías necesarias para el desarrollo de dicha aplicación y su objetivo principal es adquirir el conocimiento y la experiencia necesarios sobre las frecuencias de Terahercios para poner estas tecnologías a disposición del sistema I+D+i a nivel nacional, haciendo aportaciones a su evolución y desarrollo. Cabe destacar que, en estas elevadas frecuencias, existen varias limitaciones tecnológicas tales como: las dimensiones reducidas de los circuitos debido a la pequeña longitud de onda, un número limitado de empresas que ofrezcan componentes en estas bandas y las limitaciones en equipos en términos de coste elevado, mayor rendimiento y una precisión más exigente. Todas estas restricciones hacen más complejo el desarrollo de sistemas a estas frecuencias comparado con frecuencias más bajas de microondas. Por este motivo el trabajo ha contribuido al avance y la extensión de los rangos frecuenciales cubiertos hasta ahora por las tecnologías de fabricación y medida con las que se tenía experiencia en nuestro grupo de investigación, llevándonos a cubrir la banda W, puerta de los Terahercios. Centrándonos en el trabajo en la banda W, comprendida entre 75 y 110 GHz, se ha realizado una comparativa entre dos tipos de sistemas de Imaging, activos y pasivos, analizando sus parámetros característicos. Y para ello, se han llevado a cabo estudios sobre las tecnologías disponibles y se han desarrollado los diseños de estructuras y circuitos necesarios para implementarlos. Así, se han caracterizado e integrado en montajes con accesos en guía de onda de amplificadores de bajo ruido, de media potencia, detectores de RF y radiómetro de potencia total combinando los anteriores. Se han diseñado y fabricado un filtro de líneas acopladas, así como diferentes versiones de detectores basados en un diodo zero bias, el cual ha sido previamente modelado. Además se ha modelado el ruido en baja frecuencia de diodos que forman parte de detectores ya disponibles en más baja frecuencia, como paso previo para hacerlo después en banda W. Para tener una perspectiva de sistema, más allá de los componentes individuales, se han llevado a cabo algunos experimentos sencillos para evaluar la fiabilidad de los procedimientos de simulación EM de los escenarios de obtención de imágenes y su interacción con simulaciones de circuitos y sistemas. I would like to thank mainly the financial support provided by the Spanish government through project CONSOLIDER-INGENIO CSD2008-00068 (TERASENSE) and the University of Cantabria Industrial Doctorate programme 2014, project: “Estudio y Desarrollo de Tecnologías para Sistemas de Telecomunicación a Frecuencias Milimétricas y de Terahercios con Aplicación a Sistemas de Imaging en la Banda 90 GHz-100GHz”. Additional financial support was provided by the Spanish government through projects CONSOLIDER-INGENIO CSD2010-00064, CSD2008-00066, FEDER co-founded TEC2011-29126-C03-01, TEC2011-29264-C03-01, TEC2010-21496-C03-01 and TEC2014-58341-C4-1-R.

Universidad de Sevilla. Grado Filológica Hispánica

Ingeniería de Telecomunicación

Máster Universitario en Enseñanza del Español como Lengua Extranjera y de Otras Lenguas Modernas

Máster en Tecnologías de la Información y Comunicaciones en Redes Móviles (TICRM)

Máster en Tecnologías de la Información y Comunicaciones en Redes Móviles (TICRM)