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Hossein Ehsani,1,2 Martha Jane Mohler,1–3 Kathy O’Connor,4 Edward Zamrini,4,5 Coco Tirambulo,2 Nima Toosizadeh1–3 1Department of Biomedical Engineering, University of Arizona, Tucson, AZ, USA; 2Arizona Center on Aging, Department of Medicine, University of Arizona, Tucson, AZ, USA; 3Division of Geriatrics, General Internal Medicine and Palliative Medicine, Department of Medicine, University of Arizona, Tucson, AZ, USA; 4Neurology Department, Banner Sun Health Research Institute, Sun City, AZ, USA; 5Department of Neurology, University of Utah, Salt Lake City, UT, USA Background: Dual-task actions challenge cognitive processing. The usefulness of objective methods based on dual-task actions to identify the cognitive status of older adults has been previously demonstrated. However, the properties of select motor and cognitive tasks are still debatable. We investigated the effect of cognitive task difficulty and motor task type (walking versus an upper-extremity function [UEF]) in identifying cognitive impairment in older adults. Methods: Older adults (≥65 years) were recruited, and cognitive ability was measured using the Montreal Cognitive Assessment (MoCA). Participants performed repetitive elbow flexion under three conditions: 1) at maximum pace alone (Single-task); and 2) while counting backward by ones (Dual-task 1); and 3) threes (Dual-task 2). Similar single- and dual-task gait were performed at normal speed. Three-dimensional kinematics were measured for both motor functions using wearable sensors. Results: One-hundred older adults participated in this study. Based on MoCA score 0.26). Conclusion: This study demonstrated that counting backward by threes within a UEF dual-task experiment was a pertinent and challenging enough task to detect cognitive impairment in older adults. Additionally, UEF was superior to gait as the motor task component of the dual-task. The UEF dual-task could be applied as a quick memory screen in a clinical setting. Keywords: wearable motion sensor, gait, upper-extremity function, biomechanics, MCI, Alzheimer’s disease

Hossein Ehsani,1,2 Martha Jane Mohler,1–3 Todd Golden,2 Nima Toosizadeh1–3 1Department of Biomedical Engineering, University of Arizona, Tucson, AZ, USA; 2Arizona Center on Aging, Department of Medicine, University of Arizona, Tucson, AZ, USA; 3Division of Geriatrics, General Internal Medicine and Palliative Medicine, Department of Medicine, University of Arizona, Tucson, AZ, USA Background: Frailty can inform management approaches for individuals with COPD. However, inpatient measures of frailty are seldom employed because they are time-consuming or inapplicable for bed-bound patients. We investigated the feasibility and potential of an innovative sensor-based upper-extremity function (UEF) test for frailty assessment in predicting adverse outcomes. Methods: Hospitalized patients with COPD-related exacerbations (aged ≥55 years) were recruited and performed the UEF test within 24 hours of admission. UEF parameters were obtained and fed into our previously developed frailty model to calculate frailty status (non-frail, pre-frail, and frail) and frailty score (0: extreme resilience to 1: extreme frailty). In-hospital (length of stay) and post-discharge (discharge disposition, 30-day exacerbation with treatment, and all-cause 30-day readmission) outcomes were collected. Associations between UEF frailty and outcomes were investigated using ANOVA and logistic models adjusted for demographic data. Results: In total, 42 patients were recruited. All participants were able to perform the UEF test. Based on UEF, participants were stratified into three groups of non-frail (n=6, frailty score =0.18±0.09), pre-frail (n=14, frailty score =0.45±0.09), and frail (n=22, frailty score =0.78±0.11). Both frailty status and frailty score were significantly associated with unfavorable discharge disposition (P0.5) nor 30-day exacerbation with treatment (P>0.70). Age was only significantly associated with unfavorable discharge disposition (P=0.048). Conclusion: In agreement with previous work, the current findings underline the importance of measuring frailty for risk-stratification of COPD patients. The UEF was feasible and easily performed among all hospitalized COPD patients. In this study, we have shown that, using our quick and objective frailty measures, COPD patients can be prospectively risk-stratified in terms of unfavorable discharge disposition and all-cause 30-day readmissions. Keywords: COPD, frailty, adverse health outcomes, early readmission, biomechanics, gait, wearable sensors

The extent of relative tilt angle, crystalline quality and relaxation of Ga(sub x)In(sub 1-x)Sb layers grown on (001) GaSb substrates by organometallic vapor phase epitaxy were studied through double-crystal x-ray diffraction and transmission electron microscopy. An unexpectedly large tilt was produced between Ga0.8In0.2Sb epitaxial layers and oriented (001) GaSb substrates which has not been previously reported. Correlation between the tilt formation and the relaxation indicates that the lattice relaxation is affected by the tilt between the epilayer and the substrate.

The dependence of the plasma wavelength and free-carrier absorption on the doping concentration in silicon was investigated. Two methods of introducing impurities into Si were utilized to attain high doping concentration. One was the diffusion method employing spin-on dopants. The other technique was doping by ion implantation followed by thermal annealing with a capped layer of doped glass. The high temperature annealing which was needed to activate the dopant atoms and to repair the implantation damage also produced significant redistribution of the dopants.

Presents a study which examined the interfacial nucleation of compounds for thin film cobalt-mercury[sub 1-x]cadmium telluride contacts. Experimental methods; Results; Discussion and conclusion.

Reports on the results of structural studies of the interfaces between sputter-deposited copper thin films and cadmium-tellerium substrates. Deposition of the thin film structures; Reactions of copper thin films; Time requirements in the deposition.

Investigates the interfacial reaction between thin nickel film and tellurium using transmission electron microscopy and diffraction. Use of Auger depth profiles to determine the distribution of tellurium, cadmium, mercury and nickel with respect to substrates; Experimental procedures; Result and conclusion of the study.

In this study, we deal with the problem of a steady two-dimensional magnetohydrodynamic ( MHD) flow of a dusty fluid over a stretching hollow cylinder. Unlike the commonly employed thermal conditions of constant temperature or constant heat flux, the present study uses a convective heating boundary condition. The multi-step differential transform method (multi-step DTM), one of the most effective methods, is employed to find an approximate solution of the system of highly nonlinear differential equations governing the problem. Comparisons are made between the results of the proposed method and the numerical method in solving this problem and excellent agreement has been observed. The influence of important parameters on the flow field and heat transfer characteristics are presented and discussed in detail. The results show that both the thermal boundary layer thickness and the heat transfer rate at the wall increases with increasing Biot number Bi, while it has no effect on the skin friction coefficient. © 2013 Wiley Periodicals, Inc. Heat Trans Asian Res, 43(3): 221-232, 2014; Published online 30 August 2013 in Wiley Online Library (). DOI 10.1002/htj.21073 [ABSTRACT FROM AUTHOR]