Portable low profile antenna at X-band

An antenna which has been conceived as a portable system for satellite communications based on the recommendations ITU-R S.580-6 and ITU-R S.465-5 for small antennas, i.e., with a diameter lower than 50 wavelengths, is introduced. It is a planar and a compact structure with a size of 40×40×2 cm. The antenna is formed by an array of 256 printed elements covering a large bandwidth (14.7%) at X-Band with a VSWR of 1.4:1. The specification includes transmission (Tx) and reception (Rx) bands simultaneously. The printed antenna has a radiation pattern with a 3dB beamwidth of 5°, over a 31dBi gain, and a dual and an interchangeable circular polarization

Do recruiters prefer applicants with similar skills? Evidence from a randomized natural experiment

In this paper we examine the potential existence of a similar-to-me effect in terms of skills between recruiters and applicants. Using evidence from entry exams to the Spanish Judiciary, where applicants are randomly assigned across evaluation committees, we find that committee members tend to be more demanding at those stages where they are more knowledgeable. As a result, applicants who excel in the same dimensions as recruiters are more likely to be hire

Why do I like people like me?

In many dimensions the ability to assess knowledge depends critically on the observer's own knowledge of that dimension. Building on this feature, this paper offers both theoretical and empirical evidence showing that, in those tasks where multidisciplinary knowledge is required, evaluations exhibit a similar-to-me effect: candidates who excel in the same dimensions as the evaluator tend to be ranked relatively higher. It is also shown that, if races or genders differ in their distribution of ability, group discrimination will arise unless evaluators (i) are well informed about the extent of intergroup differences and (ii) they may condition their assessments on candidates' group belonging

Adaptive neurofuzzy ANFIS modeling of laser surface treatments

This paper introduces a new ANFIS adaptive neurofuzzy inference model for laser surface heat treatments based on the Green’s function. Due to its high versatility, efficiency and low simulation time, this model is suitable not only for the analysis and design of control systems, but also for the development of an expert real time supervision system that would allow detecting and preventing any failure during the treatment

Modular Planar Antenna at X-band for satellite communications

An antenna which has been conceived as a portable system for satellite communications based on the recommendations ITU-R S.580-6 [1] and ITU-R S.465-5 [2] for small antennas, i.e., with a diameter lower than 50 wavelengths, is introduced. It is a planar and a compact structure with a size of 40×40×2 cm. The antenna is formed by an array of 256 printed elements covering a large bandwidth (14.7%) at X-Band. The specification includes transmission (Tx) and reception (Rx) bands simultaneously. The printed antenna has a radiation pattern with a 3dB beamwidth of 5°, over a 31dBi gain, and a dual and an interchangeable circular polarizatio

Aislamiento y caracterización de un bacteriófago específico para aggregatibacter actinomycetemcomitans, agente etiológico de la periodontitis agresiva.

Tesis (Químico Farmacéutico)El término enfermedad periodontal se refiere a un conjunto de enfermedades inflamatorias que afectan los tejidos de soporte del diente, esta patología resulta de un desequilibrio entre la interacción inmunológica del hospedero y la flora de la placa dental. Las manifestaciones clínicas de esta enfermedad se agrupan bajo el nombre de gingivitis y periodontitis. Entre las bacterias relacionadas con la instauración de esta patología, la espeCIe Aggregatibacter actinomycetemcomitans se ha asociado especialmente con el desarrollo de la periodontitis agresiva, forma de infección que se presenta con una frecuencia considerable en individuos jóvenes. La aparición cada vez más frecuente de bacterias resistentes al tratamiento con antibióticos ha hecho que, se piense de nuevo en los bacteriófagos como una alternativa terapéutica al empleo de los antimicrobianos actuales. Los fagos corresponden a pequeñas partículas virales capaces de destruir específicamente bacterias. Existen numerosos estudios que apoyan la eficacia de esta terapia y por ende sugieren que la fagoterapia es una alternativa a considerar. Además, por muchos años, los bacteriófagos han servido como poderosas herramientas genéticas para el estudio de mecanismos de patogenicidad bacteriana. En el presente proyecto se aislaron, a partir de pacientes diagnosticados de enfermedad periodontal y personas sanas, siete cepas de Aggregatibacter actinomycetemcomitas las que fueron utilizadas para la búsqueda y aislamiento del nuevo bacteriófago Aabü l. El análisis de las curvas de crecimiento en medios suplementados sugiere que los viriones aislados son capaces de infectar las cepas susceptibles prescindiendo de la presencia de calcio y magnesio en el medio. Las características de la curva de infección y las placas de lisis indican que se trata de un fago lisogénico. Se logró la extracción del material genético viral y su digestión con enzimas de restricción 10 que demostró que se trata de DNA cuyo tamaño molecular aproximado es de 24,3 Kpb. Este parámetro fue estimado por comparación de las migraciones e1ectroforéticas de la digestión con la endonucleasa Bgl TI y el estándar de peso molecular de 1 Kb