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A combined diffuse speckle contrast analysis (DSCA)-near-infrared spectroscopy (NIRS) system is proposed to simultaneously measure qualitative blood flow and blood oxygenation changes in human tissue. The system employs an optical switch to alternate two laser sources at two different wavelengths and a CCD camera to capture the speckle image. Therefore, an optical density can be measured from two wavelengths for NIRS measurements and a speckle contrast can be calculated for DSCA measurements. In order to validate the system, a flow phantom test and an arm occlusion protocol for arterial and venous occlusion were performed. Shorter exposure times (<1 ms) show a higher drop (between 50% and 66%) and recovery of 1/KS² values after occlusion (approximately 150%), but longer exposure time (3 ms) shows more consistent hemodynamic changes. For four subjects, the 1/KS² values dropped to an average of 82.1 ± 4.0% during the occlusion period and the average recovery of 1/KS² values after occlusion was 109.1 ± 0.8%. There was also an approximately equivalent amplitude change in oxyhemoglobin (OHb) and deoxyhemoglobin (RHb) during arterial occlusion (maxRHb = 0.0085±0.0024mM/DPF, minOHb=-0.0057±0.0044mM/DPF). The sensitivity of the system makes it a suitable modality to observe qualitative hemodynamic trends during induced physiological changes. [ABSTRACT FROM AUTHOR]

This study examines differences in bother reported by caregivers (n=144) of older, demented clients enrolled in a Medicaid waiver program who exhibit problem behaviors related to ADL performance. Regression analysis was used to examine the relationship between ADL-related bother and race (60% were African American), controlling for frequency of the behavior, caregiver gender, frequency of caregiver assistance with ADLs, and client's MMSE score. Frequency of behavior, MMSE score, and race were all significant factors (p

Background: In this paper, we observed a discrepancy of penile hemodynamics dependent on location by using near infrared spectroscopy (NIRS) sensor, and showcase NIRS as a potentially suitable sensor in supplementing the diagnosis and treatment of erectile dysfunction. Methods: To observe the effect that location has on penile hemodynamics, the NIRS sensor was placed on the top and the side of genital organ, and oxy-(HbO), deoxy-(RHb), and total (HbT) hemoglobin concentration changes were acquired. Our results from 6 healthy subjects show that hemodynamic changes vary depending on where the probe was placed. To observe a statistical difference between the signals, a Wilcoxon signed-rank test was performed. Results: The result shows a significant difference (p < 0.05) between concentration changes of RHb and HbT depending on the probes' location. Moreover, the sensor placed on the top of the organ shows a rise of HbO and HbT concentration while RHb concentration decreased. However, hemodynamics from the side of the organ showed that RHb concentration increased along with HbO. Conclusions: The outcomes demonstrates an ability of NIRS to be sensitive enough to detect the different hemodynamic changes in various locations of a healthy male genital organ during visual sexual stimulation. The results also show the importance of sensor location on the genital organ for the resulting hemodynamic changes. We can foresee our results as a way for clinicians to obtain more accurate hemodynamic measurements from the penis, and also show the likelihood for NIRS enhanced diagnosis tool of male erectile dysfunction over the current standards. [ABSTRACT FROM AUTHOR]

Closure is a problem of defining the convective intensity in a given parameterization. In spite of many years of efforts and progress, it is still considered an overall unresolved problem. The present article reviews this problem from phenomenological perspectives. The variables that are expected to contribute in defining the convective intensity are listed, and their statistical significances identified by observational data analyses are reviewed. A possibility is discussed for identifying a correct closure hypothesis by performing a linear stability analysis of tropical convectively-coupled waves with various different closure hypotheses. Various individual theoretical issues are considered from various different perspectives. Finally, it is emphasized that the dominant physical factors controlling convection differ between the tropics and extra-tropics, as well as between oceanic and land areas. Both observational as well as theoretical analyses, often focused on the tropics, do not necessarily lead to conclusions consistent with our operational experiences focused on midlatitudes. Though we emphasize the importance of the interplays between these observational, theoretical and operational perspectives, we also face challenges for establishing a solid research framework that is universally applicable. [ABSTRACT FROM AUTHOR]