ABSTRACT
Direction finding (DF) systems are used to determine the direction-of-arrival (DoA) of electromagnetic waves, thus allowing for the tracking of RF sources. In this paper, we present an alternative formulation of antenna arrays for modeling DF systems. To improve the accuracy of the data provided by the DF systems, the effects of mutual coupling in the array, polarization of the received waves, and impedance mismatches in the RF front-end receiver are all taken into account in the steering vectors of the DoA algorithms. A closed-form expression, which uses scattering parameter data and active-element patterns, is derived to compute the receiver output voltages. Special attention is given to the analysis of wave polarization relative to the DF system orientation. Applying the formulation introduced here, a complete characterization of the received waves is accomplished without the need for system calibration techniques. The validation of the proposed model is carried out by measurements of a 2.2 GHz DF system running a MUSIC algorithm. Tests are performed with a linear array of printed monopoles and with a planar microstrip antenna array having polarization diversity. The experimental results show DoA estimation errors below 6° and correct classification of the polarization of incoming waves, confirming the good performance of the developed formulation.
ABSTRACT
ABSTRACT This paper reports on a patient with initial clinical diagnosis of Autism Spectrum Disorder level 3 and genetically confirmed as Syngap1 Syndrome (Synaptic RasGTPase activating protein). This study aimed to show the importance of genetic testing and accurate diagnoses associated with syndromes for the planning and accomplishment of dental treatments. The new diagnosis allowed reorganization of the plan and was useful in decision-making for the clinical practice of dental treatment for patients diagnosed with Syngap1.
RESUMO Apresentamos um paciente com diagnóstico clínico inicial de Transtorno do Espectro Autista nível 3 e geneticamente confirmado como Síndrome Syngap1 (proteína ativadora Synaptic RasGTPase). O objetivo deste estudo foi mostrar a importância de exames genéticos e diagnósticos precisos associados a síndromes na elaboração do planejamento e condução de tratamentos odontológicos. O novo diagnóstico possibilitou a reorganização do plano e pôde ser útil na tomada de decisão para prática clínica do tratamento odontológico de pacientes com diagnóstico de Syngap1.
ABSTRACT
Domoic acid (DA) or Amnesic Shellfish Poisoning (ASP) produced by the genus Pseudo-nitzschia diatom was investigated in two seasonal periods in fishing areas of Katsuwonus pelamis in the South Atlantic Ocean. Higher DA concentrations were found in spring compared to winter. Pseudo-nitzschia spp. more quantified in winter than in spring, while P. pungens, a species among the most reported for an AD toxic potential, was only found in spring.
Subject(s)
Environmental Monitoring , Kainic Acid/analogs & derivatives , Phytoplankton/chemistry , Seawater/chemistry , Atlantic Ocean , Brazil , Kainic Acid/analysis , SeasonsABSTRACT
Explorando os resultados de uma pesquisa de campo que interrogou 100 empresas de base tecnológica brasileiras, este artigo aborda as relações de cooperação em que essas empresas se envolvem. Conclui-se que a adoção de esquemas de cooperação é limitada e muito concentrada nas relações com instituições acadêmicas, tendendo a caracterizar redes pouco densas, configurando um tipo de arranjo que não é o mais favorável ao desempenho inovativo.