ABSTRACT
We achieved three-dimensional (3D) computational ghost imaging with multiple photoresistors serving as single-pixel detectors using the semi-calibrated lighting approach. We performed imaging in the spatial frequency domain by having each photoresistor obtain the Fourier spectrum of the scene at a low spectral coverage ratio of 5%. To retrieve a depth map of a scene, we inverted, apodized, and applied semi-calibrated photometric stereo (SCPS) to the spectra. At least 93.5% accuracy was achieved for the 3D results of the apodized set of images applied with SCPS in comparison with the ground truth. Furthermore, intensity error map statistics obtained at least 97.0% accuracy for the estimated surface normals using our method. Our system does not need special calibration objects or any additional optical components to perform accurate 3D imaging, making it easily adaptable. Our method can be applied in current imaging systems where multiple detectors operating at any wavelength are used for two-dimensional (2D) imaging, such as imaging cosmological objects. Employing the idea of changing light patterns to illuminate a target scene and having stored information about these patterns, the data retrieved by one detector will give the 2D information while the multiple-detector system can be used to get a 3D profile.
ABSTRACT
Interventions are needed to address each phase of the HIV care continuum in order to improve health outcomes and reduce likelihood of HIV transmission. The purpose of this study was to assess the impact of a community- and clinic-based intervention designed and implemented to reengage individuals who were lost to HIV care. Eligible participants had either never engaged in HIV care or had not had a medical visit for at least 12 months. Participants enrolled in a community- and clinic-based intervention that included intensive case management, access to a community nurse and peer navigator, as well as emergency stabilization funds. Data were collected at baseline and 6-month time points by the case managers; which included sociodemographics, general health, abstracted HIV viral loads and CD4 cell counts from their medical records. Descriptive and GEE analyses were conducted to assess changes from baseline to 6 months. A total of 322 participants enrolled over a 5-year period, of whom the majority were male (n = 250) and African American with a mean age of 42.0 years. After 6 months of the intervention, there was a significant increase of individuals who had undetectable HIV viral loads and their median CD4 cell counts increased (p < 0.01 for both). General health improved as well (p < 0.01). It is clear that this method of engagement, while staff intensive, is successful at engaging and retaining individuals in HIV care at least through 6 months.