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This paper discusses the design options and tradeoffs of the key performance parameters, technology, and costs of dual-polarized and two-dimensional active phased array antenna for an atmospheric airborne radar system. The design proposed provides high-resolution measurements of the air motion and rainfall characteristics of very large storms that are difficult to observe with a ground-based radar system. Parameters such as antenna size, wavelength, beamwidth, transmit power, spatial resolution, along-track resolution, and polarization have been evaluated. The paper presents a performance evaluation of the radar system. Preliminary results from the antenna front-end section that corresponds to a Line Replacement Unit (LRU) are presented.

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This paper presents a unique instrument for characterizing the impact of wet radomes in radar systems. The proposed technique enables full radio frequency (RF) characterization of the radome, by evaluating its performance under a variety of conditions, including dirtiness, wetness, ice formation, and varying temperature, and providing a potential solution for future wet radome calibration methods. The reflections generated from the wet radome surface, measured from a high-resolution probe, are combined with an estimation of water absorption as a function of the precipitation rain rate, to calculate the attenuation introduced by the wet radome. This instrument is a cost-effective solution that can be integrated into an existing or new radar system.

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During 12 months of follow-up in a randomized double-blind controlled field study, a killed whole-promastigote vaccine cocktail plus bacille Calmette-Guérin (BCG) adjuvant significantly reduced the incidence of cutaneous leishmaniasis (CL) in Ecuadorian children, compared with BCG alone. To determine how much longer protection might continue, the study was reblinded to permit 48 additional months of follow-up. During months 13-18, CL incidence remained lower in the vaccine group, compared with that in the control group (5.9% vs. 13.8%; chi2=8.8; P=.003), with vaccine efficacy calculated at 56.5% (95% confidence interval, 18.7%-76.7%); however, during months 24-60, no significant between-group differences were detected. Periodic administration of boosters may be necessary to maintain whole-parasite-vaccine protection against New World CL.

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