Beam-forming capabilities of a plasma circular reflector antenna

A gaseous plasma antenna array (PAA) is an aggregate of plasma discharges and possibly conventional metallic radiating elements, and it constitutes a promising alternative to metallic antennas for applications in which fast reconfiguration of radiation pattern, and gain is desired; such properties can be achieved by exploiting the electronic switch on/off condition of plasma discharges, and tuning of the plasma parameters. Here, the authors present a reconfigurable PAA that features a central metallic half-wavelength dipole working around 1.45\u2005GHz, surrounded by a planar circular lattice of cylindrical plasma discharges. Customised plasma discharges have been realised, and filled with argon gas at 2\u2005mbar so as to have a complete control on the plasma discharge properties (e.g. plasma frequency, collisional frequency). The magnitude of the reflection coefficient, and the gain pattern on the H-plane have been investigated numerically and experimentally; numerical and experimental results exhibit a good agreement and show that the central intrinsically omnidirectional antenna can provide simple beamforming capabilities upon turning on a subset of plasma discharges; as these plasma discharges are turned on, the authors have observed a maximum gain of 3c5\u2005dBi, a half-power beam width of 80 18, and an angular steering resolution of 3c15 18

REGULUS CubeSat Propulsion System: In-Orbit Operations

A robust, versatile, and cost-effective propulsion system to provide wide mobility to small satellite platforms and nanosatellite deployers. A Plug&Play propulsion system designed to be easily integrated into different satellite platforms and to match customer\u27s requirements, with minimal customization efforts and costs

Identification of protein-protein interactions of human HtrA1.

The human heat shock protein HtrA1, a member of the HtrA family of serine proteases, is a evolutionarily highly conserved factor which displays a widespread pattern of expression. The yeast two-hybrid technique was employed to identify new cellular proteins physically interacting with HtrA1, and thus potential targets of this serine protease. An enzymatically inactive HtrA1 point mutant, HtrA1-S328A, was generated and used as bait in a yeast two-hybrid system. Fifty-two plasmids were isolated from primary positive yeast clones. Subsequent sequencing and BLAST analysis revealed cDNAs encoding for 13 different proteins. These putative binding partners of HtrA1 appeared to be a) components of extracellular matrix; b) factors related to signal pathways, and c) unknown proteins. Among the 13 positive clones identified and reported here, it is worth of note that the interaction of HtrA1 with tubulin and collagen (extracellular matrix proteins) and with tuberin (cytoplasmic protein) is confirmed by other studies, and this further supports previous findings in which HtrA1 can be found active as an intracytoplasmic protein or as secreted protein as well

REGULUS Iodine Electric Propulsion System Integration in CubeSats’ Platforms and Testing

REGULUS is an electric propulsion (EP) system for CubeSats at TRL8 and now waiting for the IoD flight in late 2020. REGULUS system is provided for integration with all electronics, fluidic line, iodine tank and structures for total mass below 3 kg. Thanks in particular to the Magnetically Enhanced RF Plasma Thruster (MEPT) technology and the use of iodine propellant, the system can provide 3000Ns of total impulse in a 93.8 x 95.0 x 150.0 mm volume performance, fitting in a 1.5U Cubesat. REGULUS includes the whole propulsion package for integration in CubeSats and MicroSats as well as small CubeSat carriers. The system is composed by the thruster, the electronics (PPUs and PCU) the fluidic line and the tank. The main features of REGULUS are the presence of a simple architecture, a thruster with no neutralizer and grids, no high DC-voltage PPU and the use of solid iodine as propellant, that can be substituted with Xenon fluidic line and tank when required. Its first mission will be onboard of Unisat-7 by GAUSS. The flight will take place in late 2020 in a Soyuz flight. During the mission, REGULUS will allow Unisat-7 to perform an orbit descending maneuver, drag compensation in VLEO and decommissioning

Impressão digital vs impressão convencional em implantologia dentária

INTRODUÇÃO: A mudança mais significativa no campo dentário nos últimos anos é, sem dúvida, o desenvolvimento da medicina dentária digital. Em particular, um segmento em crescimento é o dos scanners intra-orais, que têm como objectivo substituir a impressão clássica. OBJETIVO: O objetivo principal desta tese foi realizar uma revisão sistemática integrativa da literatura sobre o tema Impressão digital vs impressão convencional em implantologia dentária, com foco tanto em implantes em nível ósseo quanto em tecido. MATERIAIS E MÉTODOS: Pesquisa de artigos científicos na base de dados PubMed (National Library of Medicine), utilizando várias combinações das palavras chaves: ‘’dental digital impression’’; ‘’digital dentistry’’; ‘’intraoral scanner’’; ‘’conventional impression’’; ‘’implants’’ restrita aos últimos 6 anos. RESULTADOS: Selecão de 21 artigos, que se enquadravam no tema, após a aplicação dos critérios de inclusão e de exclusão. DISCUSSÃO: A exactidão da impressão digital é influenciada pelo tipo de scanbodies utilizados, os mais longos e os da marca do fabricante são os melhores. A distância interimplantar tem uma influência negativa sobre a qualidade da impressão. A técnica dos implantes com ferula dá os melhores resultados. A impressão não é influenciada pelo tipo de conexão ou pelo ângulo do implante até 15°. A qualidade da impressão depende fortemente do tipo de scanner intraoral utilizado. CONCLUSÃO: As impressões digitais obtêm resultados comparáveis em termos de precisão e exactidão às impressões de silicone tradicionais, ao mesmo tempo que oferecem vantagens como um maior conforto do paciente e uma gestão mais fácil dos dados recolhidos