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In this work the design and the Selective Laser Melting (SLM) manufacturing of single- and dual-band high-performance horns operating within the Ku to V bands are considered. A smooth wall architecture has been preferred in order to simplify the manufacturing and enhancing the SLM quality. Three prototypes have been designed, built and successfully tested.

Additive manufacturing technologies are currently envisaged to boost the development of a next generation of microwave devices intended for satellite telecommunications. Due to their excellent electromagnetic and mechanical properties, metal waveguide components are key building blocks of several radio frequency (RF) systems used in these applications. This article reports the perspectives deriving from the use of laser powder bed fusion (L-PBF) technology to the production of high-performance microwave waveguide devices. A robust design of filters has been implemented in several prototypes manufactured in AlSi10Mg alloy. The corresponding measured performance confirm the applicability of the L-PBF process to the intended applications

Additive manufacturing technologies have been increasingly applied to the development of radio frequency components in the past few years. Indeed, the free-form capability of these processes allows for the design of novel components, whose actual implementation through conventional machining is rather complex or even not possible. This paper describes a monolithic WR51 component integrating three radio frequency functionalities, namely, bending, twisting, and filtering. Three aluminum prototypes with different bending/twisting radii have been manufactured through the selective laser melting process. They exhibit a measured rejection higher than 60 dB in 17.5 and 21.2 GHz, and a measured return loss better than 20 dB in 12.5 and 15 GHz. Significant mass and envelope reductions (higher than 60% depending on the bending/twisting radius) with respect to the reference subsystem with distinct waveguide components are achieved. These results assess the effectiveness of 3-D metal printing in the miniaturization and integration of waveguide systems.

A new E-plane filtering structure suitable for very high-power telecom satellite applications is presented. The conceived configuration exploits the design flexibility provided by cascading highly integrated step/stub resonators with pseudoelliptic frequency responses. Several design examples of filters and diplexers in Ku-, K-, and Q-band are reported and supported by experimental tests campaigns. The components have been designed with a full-wave 2-D spectral element method. Prototypes have been realized in aluminum clam-shell technology. Excellent agreement between the models and the experimental results has been achieved. An alternative manufacturing of the proposed architecture based on the selective laser melting technology is also reported. The attractiveness of the structure in view of this emerging additive manufacturing solution is demonstrated. The main advantages of the proposed filter configuration suitable for components operated in heavily loaded multi-carrier environment are: compact design, very low losses, high rejection, and high power-handling capability.

El leiomiosarcoma es un tumor maligno mesenquimatoso infrecuente. Su incidencia es menor al 10% de los casos de los sarcomas de tejidos blandos. Afecta a ambos sexos y su presenta entre la quinta y sexta década de la vida, los pacientes inmunocomprometidos son más propensos a desarrollar este tumor. Se lo clasifica en leiomiosarcoma cutáneo (derivado del músculo piloerector del pelo y ubicado histológicamente a nivel dérmico) y el leiomiosarcoma subcutáneo (derivado del músculo liso de las paredes vasculares). Su diagnóstico es clínico e histológico siendo esencial la inmunohistoquímica. Los diagnósticos diferenciales son diversos tumores cutáneos. El tratamiento de elección de este tumor es con la cirugía dónde debe tomarse un margen de seguridad de 3 cm o la cirugía micrográfica de Mohs. El fracaso terapéutico está dadopor la recurrencia que es muy frecuente en este tumor., Facultad de Ciencias Médicas

Acetaminophen (paracetamol-P) is a widely used analgesic-antipyretic drug with no anti inflammatory effects and its rate of adverse hypersensitivity reactions is very low. On the contrary non-steroidal anti-inflammatory drugs (NSAIDs) are commonly involved in side effects. Celecoxib (CE) is a novel drug, with high selectivity and affinity for COX-2 enzyme.We evaluated the tolerability of CE in a group of patients with documented history of adverse cutaneous reactions to P and to classic NSAIDs.We studied 29 patients with hypersensitivity to P and classic NSAIDs. The diagnosis of P-induced skin reactions was based on in vivo challenge. The placebo was blindly administered at the beginning of each challenge. After three days, a cumulative dosage of 200 mg of CE in refracted doses was given. After 2-3 days, a single dose of 200 mg was administered. All patients were observed for 6 hours after each challenge, and they were controlled again after 24 hours to exclude delayed reactions. The challenge was considered positive if one or more of the following appeared: erythema, rash or urticaria-angioedema.No reaction was observed with placebo and twenty eight patients (96.5 %) tolerated CE. Only one patient developed a moderate angioedema of the lips.Only one hypersensitivity reaction to CE was documented among 29 P-intolerant patients. Thus, we conclude that CE is a reasonably safe alternative which can be used in subjects who do not tolerate P.