THE EXPERIENCE OF REAL WORLD CONTEXTS IN VIRTUAL ENVIRONMENTS:

The purpose of this qualitative case study was to develop a deeper understanding of adult learners’ experiences participating in an online, problem-based course, and to enhance our understanding of PBL as a means to foster a sense of context in these environments. The findings the perception of meaningful context, is constantly mediated through differences among group members, and the need to manage group and interpersonal processes, particularly around unresolved issues of authority and intimacy. Implications for adult educators are discussed

Identification of bacterial isolates recovered from the surface of cleanroom operators' garments following wear.

Contamination of sterile pharmaceutical products can have serious consequences, in worst case scenario resulting in patient death. Cleanroom operators are the primary source of microbial contamination, where the surface of their specialist sterile clothing garments is subject to such contamination during wear. In turn these garments become a transmission vector for microorganisms within the cleanroom environment. Insight into identification of predominant bacterial isolates from garment surfaces would help to establish their original source and probable contamination route. This should assist possible intervention strategies to mitigate against this contamination. The research aimed to determine identity of representative bacterial isolates recovered from the surface of cleanroom operators' garments following wear within a cleanroom. Following isolation and purification of bacterial isolates, 16S rRNA gene sequencing was used to establish species identity for isolates recovered from the surface of male and female operators' garments following wear within the cleanroom environment. Of the 47 isolates recovered from the surface of garments, 16S rRNA gene sequencing successfully identified 94% to genus level and 77% to species level. Most were confirmed as Gram - positive bacteria; predominantly species of Staphylococcus, Micrococcus and Bacillus. The isolates recovered from the surface of female operatives' garments were more diverse than those retrieved from male counterparts. Most isolates recovered from garments were found to be skin commensals, with nearly 70% attributed to the operators within the environment. The remainder were credited to contamination of garments with species of environmental origin. Whilst most bacteria identified present minimal threat to healthy individuals, certain of these are opportunistic pathogens, presenting a hazard for immunocompromised and/or those with underlying health conditions

Motor Timing Intraindividual Variability in Amnestic Mild Cognitive Impairment and Cognitively Intact Elders at Genetic Risk for Alzheimer’s Disease

Introduction: Intraindividual variability (IIV) in motor performance has been shown to predict future cognitive decline. The apolipoprotein E-epsilon 4 (APOE-ε4) allele is also a well-established risk factor for memory decline. Here, we present novel findings examining the influence of the APOE-ε4 allele on the performance of asymptomatic healthy elders in comparison to individuals with amnestic MCI (aMCI) on a fine motor synchronization, paced finger-tapping task (PFTT). Method: Two Alzheimer’s disease (AD) risk groups, individuals with aMCI (n = 24) and cognitively intact APOE-ε4 carriers (n = 41), and a control group consisting of cognitively intact APOE-ε4 noncarriers (n = 65) completed the Rey Auditory Verbal Learning Test and the PFTT, which requires index finger tapping in synchrony with a visual stimulus (interstimulus interval = 333 ms). Results: Motor timing IIV, as reflected by the standard deviation of the intertap interval (ITI), was greater in the aMCI group than in the two groups of cognitively intact elders; in contrast, all three groups had statistically equivalent mean ITI. No significant IIV differences were observed between the asymptomatic APOE-ε4 carriers and noncarriers. Poorer episodic memory performance was associated with greater IIV, particularly in the aMCI group. Conclusions: Results suggest that increased IIV on a fine motor synchronization task is apparent in aMCI. This IIV measure was not sensitive in discriminating older asymptomatic individuals at genetic risk for AD from those without such a genetic risk. In contrast, episodic memory performance, a well-established predictor of cognitive decline in preclinical AD, was able to distinguish between the two cognitively intact groups based on genetic risk

Physical Activity Reduces Hippocampal Atrophy in Elders at Genetic Risk for Alzheimer\u27s Disease

We examined the impact of physical activity (PA) on longitudinal change in hippocampal volume in cognitively intact older adults at varying genetic risk for the sporadic form of Alzheimer\u27s disease (AD). Hippocampal volume was measured from structural magnetic resonance imaging (MRI) scans administered at baseline and at an 18-month follow-up in 97 healthy, cognitively intact older adults. Participants were classified as High or Low PA based on a self-report questionnaire of frequency and intensity of exercise. Risk status was defined by the presence or absence of the apolipoprotein E-epsilon 4 (APOE-ε4) allele. Four subgroups were studied: Low Risk/High PA (n = 24), Low Risk/Low PA (n = 34), High Risk/High PA (n = 22), and High Risk/Low PA (n = 17). Over the 18 month follow-up interval, hippocampal volume decreased by 3% in the High Risk/Low PA group, but remained stable in the three remaining groups. No main effects or interactions between genetic risk and PA were observed in control brain regions, including the caudate, amygdala, thalamus, pre-central gyrus, caudal middle frontal gyrus, cortical white matter (WM), and total gray matter (GM). These findings suggest that PA may help to preserve hippocampal volume in individuals at increased genetic risk for AD. The protective effects of PA on hippocampal atrophy were not observed in individuals at low risk for AD. These data suggest that individuals at genetic risk for AD should be targeted for increased levels of PA as a means of reducing atrophy in a brain region critical for the formation of episodic memories

Accuracy of physical activity assessment during pregnancy: an observational study

BACKGROUND: Prenatal physical activity may improve maternal and infant health and lower future disease risk for both mother and baby; however, very few physical activity assessment methods have been validated for use during pregnancy. The purpose of this study was to evaluate the accuracy of a subjective physical activity record (PAR) and an objective activity monitor, against a reference standard to quantify moderate and vigorous physical activity (MVPA) in pregnant women. The reference standard was based on participant interviews to determine if a woman was an exerciser and confirmed with information obtained from the PAR and a heart rate monitor. METHODS: Fifty-two pregnant women completed a physical activity record (PAR) and wore a SenseWear(® )Mini Armband (SWA) activity monitor over a 7-day period at 18 weeks gestation. Total minutes spent in MVPA were totaled from both modalities and evaluated against the reference standard using contingency analysis and Pearson's chi-square test to evaluate the number of women meeting minimum prenatal physical activity recommendations (at least 3, 30 minute sessions of exercise per week). Both modalities were also tested individually and collectively to assess their ability as indicators of activity using empirically determined cut-offs as indicated by receiver-operator characteristic curves. These experimentally-derived criteria were also tested with Pearson's chi-square test. RESULTS: According to the reference standard, 13 of 52 participants (25%) met the criterion of 3, 30 minute sessions of volitional, moderate-intensity activity. When compared to the reference standard, both the PAR and SWA overestimated exercise status; 42 (81%) and 52 (100%) participants, respectively, achieved 90 minutes of MVPA (P < 0.0001 for both comparisons). Single-modality predictors of MVPA did not show a significant correlation. A composite predictor of MVPA offered the most favorable option for sensitivity and specificity (true positives, n = 8 and true negatives, n = 36) using cut-offs of 280 and 385 minutes/week for the PAR and SWA, respectively. CONCLUSION: Compared to the reference standard, time spent in MVPA obtained from the PAR or SWA overestimated the prevalence of women meeting prenatal exercise recommendations. The most accurate predictor of women meeting current prenatal exercise guidelines was identified by using the PAR and SWA collectively

Speech and language therapy versus placebo or no intervention for speech problems in Parkinson's disease

Parkinson's disease patients commonly suffer from speech and vocal problems including dysarthric speech, reduced loudness and loss of articulation. These symptoms increase in frequency and intensity with progression of the disease). Speech and language therapy (SLT) aims to improve the intelligibility of speech with behavioural treatment techniques or instrumental aids

Mycobacterium tuberculosis evasion of Guanylate Binding Protein-mediated host defense in mice requires the ESX1 secretion system [preprint]

Cell-intrinsic immune mechanisms control intracellular pathogens that infect eukaryotes. The intracellular pathogen Mycobacterium tuberculosis (Mtb) evolved to withstand cell-autonomous immunity to cause persistent infections and disease. A potent inducer of cell-autonomous immunity is the lymphocyte-derived cytokine IFNγ. While the production of IFNγ by T cells is essential to protect against Mtb, it is not capable of fully eradicating Mtb infection. This suggests that Mtb evades a subset of IFNγ-mediated antimicrobial responses, yet what mechanisms Mtb resists remains unclear. The IFNγ-inducible Guanylate binding proteins (GBPs) are key host defense proteins able to control infections with intracellular pathogens. GBPs were previously shown to directly restrict Mycobacterium bovis BCG yet their role during Mtb infection has remained unknown. Here, we examine the importance of a cluster of five GBPs on mouse chromosome 3 in controlling Mycobacterial infection. While M. bovis BCG is directly restricted by GBPs, we find that the GBPs on chromosome 3 do not contribute to the control of Mtb replication or the associated host response to infection. The differential effects of GBPs during Mtb versus M. bovis BCG infection is at least partially explained by the absence of the ESX1 secretion system from M. bovis BCG, since Mtb mutants lacking the ESX1 secretion system become similarly susceptible to GBP-mediated immune defense. Therefore, this specific genetic interaction between the murine host and Mycobacteria reveals a novel function for the ESX1 virulence system in the evasion of GBP-mediated immunity

Design of a Robotic Apparatus for Simulated Motion of the Human Hand

Background: The hand is complex, in that any small disturbance to the flexor tendons, extensor tendons, and intrinsic muscles can result in dysfunction of the entire structure. We designed a robotic device to consistently load a native thumb carpometacarpal (CMC) joint in assessing the effects of ligamentous damage on stability of the thumb CMC joint. Methods: The device consisted of a mechanical plate in which to fixate a cadaveric hand, a tendon-suture routing system, a bracket to couple multiple suture lines to a cable to maintain equal force among sutures and tendons, and the finger-thumb force measurement devices. To apply force to the sutures, a cable was run from the suture coupling device to the tendon actuator and from the finger-thumb force measurement devices to the control system. The device was controlled using a Beaglebone Black microcontroller, load cells, rotary encoders, and a liquid crystal display (ie, LCD) touchscreen interface. Results: The design worked as intended in terms of basic communication, signal processing, and control functions. Cyclic loading resulted in web creep of the tissue. Using closed-loop control, the system was able to settle to a desired load. Conclusions: Use of the current device may result in improved understanding of joint movement within the hand, which may help surgeons in treating associated injuries. Future revisions to the device will aim to improve the hardware and software to accelerate the time to converging to the desired force and displacement