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The ultrasound is a common way to measure the distance or detect an object. This is usually carried out by measuring the time-of-flight of the received echoes reflected by the objects, which is a parameter easily obtained from the signal and that only provides the spatial location. In the present paper, it is presented an electronic signal generator to drive air-coupled ultrasound transducers in a wideband regime. This design is planned to be used as a new application of these sensors, normally used for distance measuring, which is to characterize materials by using the complete signal of the echo to extract more useful information. The design was made with simple materials, but mainly based on a programmed microcontroller capable of making a specified frequency sweep that allows us to create a moderate-power tone burst with the use of a switched amplifier at the output. The tone burst produced by the microcontroller varies the pulse-width in time, obtaining the controllable frequency sweep that has a wide excitation spectrum.

Partnership for Health (PfH) is an evidence-based, clinician-delivered HIV prevention program conducted in the United States for HIV-positive patients. This intervention strives to reduce risky sexual behaviors through provider-patient discussions on safer sex and HIV status disclosure. A cross-sectional, mixed-methods design was used to evaluate the dissemination and implementation of PfH, including training evaluations, an online trainee survey, and interviews with national trainers for PfH. Descriptive statistics were calculated with the categorical data, whereas thematic analysis was completed with the qualitative data. Between 2007 and 2013, PfH was disseminated to 776 individuals from 104 different organizations in 21 states/territories. The smallest proportion of trainees was physicians (6.9%). More than three-fourths of survey respondents (78.6%) reported using PfH, but less than one-third (31.8%) used the intervention with every patient. The PfH training supports the implementation of the intervention; however, challenges were experienced in clinician engagement. Tailored strategies to recruit and train clinicians providing care to HIV-positive patients are required.