Expert nurses’ use of implicit memory in the care of patients with Alzheimer's disease

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73899/1/j.1365-2648.2006.03864.x.pd

Estimating hypoxia-induced brain dysfunction and cognitive decline through exhaled breath monitoring

Abstract Background Hypoxia remains a concern for aircrew operating high performance aircraft. Sensing and mitigating hypoxia is a line of active research within the US Air Force and US Navy. It is hypothesized that changes in exhaled breath volatile organic compound content could indicate, not only changes in oxygen saturation (SpO2), but also brain activity and cognitive function. Methods On-line exhaled breath monitoring via proton transfer reaction mass spectrometry was used to observe changes in volatile organic compound concentrations during mask-free hypoxic exposures. Additionally, electroencephalography measurements in response to an odd-ball paradigm and cognitive tasks were collected throughout the exposures. Results The data show hypoxic exposures induced a physiological response including a significant reduction in SpO2, a decrease in the electroencephalography waveform peak-to-peak amplitude (p < 0.05), a significant increase in psychomotor vigilance test response time, and an increase in perceived symptomatology. Exhaled breath results indicate 19 volatile organic compound features are significantly different between hypoxia and normoxia (p < 0.05) with 13 showing an increase in exhaled breath compared to background measurements (p < 0.05). Linear mixed modeling with stepwise reduction demonstrates 7 of the features are significantly indicative of changes in SpO2 with 3 and 4 features indicative of changes in brain wave functions and psychomotor vigilance test response times, respectively. Conclusions The data establish, for the first time, differences in exhaled breath volatile concentrations that indicate changes in cognition derived from hypoxic insult

Do bone geometric properties of the proximal femoral diaphysis reflect loading history, muscle properties, or body dimensions?

Abstract Objectives: The aim of this study was to investigate activity‐induced effects from bone geometric properties of the proximal femur in athletic vs nonathletic healthy females by statistically controlling for variation in body size, lower limb isometric, and dynamic muscle strength, and cross‐sectional area of Musculus gluteus maximus. Methods: The material consists of hip and proximal thigh magnetic resonance images of Finnish female athletes (N = 91) engaged in either high jump, triple jump, soccer, squash, powerlifting, endurance running or swimming, and a group of physically active nonathletic women (N = 20). Cross‐sectional bone geometric properties were calculated for the lesser trochanter, sub‐trochanter, and mid‐shaft of the femur regions. Bone geometric properties were analyzed using a general linear model that included body size, muscle size, and muscle strength as covariates. Results: Body size and isometric muscle strength were positively associated with bone geometric properties at all three cross‐sectional levels of the femur, while muscle size was positively associated with bone properties only at the femur mid‐shaft. When athletes were compared to nonathletic females, triple jump, soccer, and squash resulted in greater values in all studied cross‐sections; high jump and endurance running resulted in greater values at the femoral mid‐shaft cross‐section; and swimming resulted in lower values at sub‐trochanter and femur mid‐shaft cross‐sections. Conclusions: Activity effects from ground impact loading were associated with higher bone geometric values, especially at the femur mid‐shaft, but also at lesser and sub‐trochanter cross‐sections. Bone geometric properties along the femur can be used to assess the mechanical stimuli experienced, where ground impact loading seems to be more important than muscle loading