Validation of Maximal Heart Rate Prediction Equations based on Sex and Physical Activity Status

International Journal of Exercise Science 8(4): 318-330, 2015. The purpose of the study was to determine if measured maximal heart rate (HRmax) was affected by sex or aerobic training status, and to determine the accuracy of three common clinical age-prediction maximal heart rate regression equations used to predict HRmax: HRmax = 220 – age, HRmax = 226 – age, and HRmax = 208 – (0.7 ∙ age). Fifty-two participants in total, 30 of which were in the active group (15 M, 15 F) and 22 subjects in the sedentary group (9 M, 13 F), within the age range of 18-25 years and with a normal BMI (18.5-24.9 kg∙m-2) underwent a Bruce maximal treadmill exercise protocol. The effect of sex and training status on HRmax was analyzed through a two-way ANOVA, and the effect of sex, aerobic training status, and regression equation on accuracy of the HRmax prediction was assessed with a three-way ANOVA (α=0.05). Overall, males had a higher HRmax than females (198.3 v. 190.4 beats • min-1 , p\u3c.001) and sedentary individuals had higher measured HRmax than active individuals (197.3 v. 191.4 beats • min-1, p=.002). Furthermore, HRmax = 208 – (0.7 ∙ age)(equation 3) calculated the smallest signed and unsigned residuals from the difference between observed HRmax and predicted HRmax values for the significant main effects of equation (3), equation x sex (females x 3), and equation x activity level (active x 3). Therefore, based on our results, we conclude that HRmax = 208 – (0.7 ∙ age) has greater accuracy than the other two equations studied for predicting observed values of HRmax in 18-25 year olds

Statistical Analysis of Spect Neuroimages in Alzheimer's Disease

We have considered a variety of problems in the statistical analysis of quantitative data extracted from Single Photon Emission Computed Tomography (SPECT) and Positron Emission Tomography (PET) neuroimages. Many of the questions of interest to investigators in this area of research were described and illustrated with analysis of some SPECT datasets. In chapter one we introduced the technique of tomograhic imaging, describing a common approach to extracting quantitative data from images and gave some background to Alzheimer's disease. In chapter two we described a major research study into Alzheimer's disease, from which most of the datasets used in this thesis were obtained. In chapter three we identified the broad categories of statistical problems into within and between group analysis of regional mean patterns and the interrelationships among regions. A SPECT dataset, consisting of Alzheimer and normal control subjects, was used to illustrate the use of univariate methods to study these problems. We saw from these analyses that it was difficult to extract clear biological interpretations with this approach due to certain features in the data extracted from the images. In particular, the presence of substantial random variation between subject data vectors meant that meaningful analysis could only be carried out after adjusting the regional data - to remove the between subject variation - prior to the analysis. Different methods of adjustment were seen to give different results here. Although not particularly evident from these data, another feature of typical imaging datasets was the large number of regions to be analysed. In chapter four we looked at the application of univariate and multivariate ANOVA type methods to compare regional mean profiles between groups and illustrated some approaches to follow-up analysis. Assumptions underlying these techniques, including normality and equality of covariance matrices were assessed as was the choice of scale for the analysis. The assumption of multivariate normality was reasonable on the square root scale in both groups, although equality of group covariance matrices was very strongly rejected. Even though many of the assumptions in the RM ANOVA may be violated for these datasets, the fact that global tests can be performed, even when the number of regions p exceeds the numbers of subject n, will make this the most viable approach. Adjusted F-tests will be appropriate in such circumstances. In chapter five, we looked at some approaches to investigating inter-relationships among regions. The most common approach here is to use simple correlation analysis among regions after adjusting data vectors for the subject effect. As in the analysis of means, the results will be strongly influenced by the form of the adjustment. Ford (1986) has shown that inferences from the results of correlation analysis are made difficult; with adjustment in the data resulting in confounding of parameters in a model of the correlation structure. Even so, between group comparisons may still provide valuable insight into a disease process. A testing scheme gave tentative evidence of differences in the correlation structure between the normal and Alzheimer groups. Multivariate exploratory techniques where used to study the interregional correlation structures. Principal components analysis demonstrated that just a few patterns accounted for most of the variation among subjects in each of the groups and that bilateral pairs of regions were very strongly correlated. Further canonical correlation analysis of the data suggested that regional profiles may be summarised into hemispheric sums and differences separately without too much loss of information. In studies with several regions being studied this would be a useful reduction of dimensions. Multi-Dimensional scaling highlighted a number of other features in our data including the measurement difficulties with smallish regions such as the basal- ganglia and some evidence of a spatial relationship between regional data. Formal analysis of the covariance structures using the spatial correlation model of Worsley et. al. (1992) gave some evidence for this feature in SPECT data, albeit using an estimated distance matrix

Generating Humanoid Multi-Contact through Feasibility Visualization

We present a feasibility-driven teleoperation framework designed to generate humanoid multi-contact maneuvers for use in unstructured environments. Our framework is designed for motions with arbitrary contact modes and postures. The operator configures a pre-execution preview robot through contact points and kinematic tasks. A fast estimation of the preview robot's quasi-static feasibility is performed by checking contact stability and collisions along an interpolated trajectory. A visualization of Center of Mass (CoM) stability margin, based on friction and actuation constraints, is displayed and can be previewed if the operator chooses to add or remove contacts. Contact points can be placed anywhere on a mesh approximation of the robot surface, enabling motions with knee or forearm contacts. We demonstrate our approach in simulation and hardware on a NASA Valkyrie humanoid, focusing on multi-contact trajectories which are challenging to generate autonomously or through alternative teleoperation approaches

Authoring and Operating Humanoid Behaviors On the Fly using Coactive Design Principles

Humanoid robots have the potential to perform useful tasks in a world built for humans. However, communicating intention and teaming with a humanoid robot is a multi-faceted and complex problem. In this paper, we tackle the problems associated with quickly and interactively authoring new robot behavior that works on real hardware. We bring the powerful concepts of Affordance Templates and Coactive Design methodology to this problem to attempt to solve and explain it. In our approach we use interactive stance and hand pose goals along with other types of actions to author humanoid robot behavior on the fly. We then describe how our operator interface works to author behaviors on the fly and provide interdependence analysis charts for task approach and door opening. We present timings from real robot performances for traversing a push door and doing a pick and place task on our Nadia humanoid robot.Comment: 8 pages, 12 figures, for Humanoids 202

Acceptability and use of a patient-held communication tool for people living with dementia: a longitudinal qualitative study

Brendan McCormack - ORCID 0000-0001-8525-8905 https://orcid.org/0000-0001-8525-8905Replaced AM with VoR on 2020-05-19Objectives: To assess the acceptability and use of a low-cost patient-held communication tool.Design: Longitudinal Qualitative interviews at three time points over 18 months and document content analysisSetting: Primary and community servicesParticipants: Twenty-eight dyads - People living with dementia in Northern Ireland and their informal carers.Interventions: a patient-held healthcare “passport” for people living with dementia.Primary and secondary outcomes: acceptability and use of the passport – barriers and facilitators to successful engagement.Results: There was a qualified appreciation of the healthcare passport and a much more nuanced, individualistic or personalised approach to its desirability and use. How people perceive it and what they actually do with it, are strongly determined by individual contexts, dementia stage and other health problems, social and family needs and capacities. We noted concerns about privacy and ambivalence about engaging with health professionals.Conclusion: Such tools may be of use but there is a need for demanding, thoughtful, and nuanced programme delivery for future implementation in dementia care. The incentivisation and commitment of General Practitioners is crucial. Altering the asymmetrical relationship between professionals and patients requires more extensive attention.This study was supported by a grant from the R&D Division of the Northern Ireland Public Health Agency & Atlantic Philanthropies COM/5017/14https://doi.org/10.1136/bmjopen-2019-036249pubpu

HOIL-1 ubiquitin ligase activity targets unbranched glucosaccharides and is required to prevent polyglucosan accumulation

HOIL‐1, a component of the linear ubiquitin chain assembly complex (LUBAC), ubiquitylates serine and threonine residues in proteins by esterification. Here, we report that mice expressing an E3 ligase‐inactive HOIL‐1[C458S] mutant accumulate polyglucosan in brain, heart and other organs, indicating that HOIL‐1’s E3 ligase activity is essential to prevent these toxic polysaccharide deposits from accumulating. We found that HOIL‐1 monoubiquitylates glycogen and α1:4‐linked maltoheptaose in vitro and identify the C6 hydroxyl moiety of glucose as the site of ester‐linked ubiquitylation. The monoubiquitylation of maltoheptaose was accelerated > 100‐fold by the interaction of Met1‐linked or Lys63‐linked ubiquitin oligomers with the RBR domain of HOIL‐1. HOIL‐1 also transferred pre‐formed ubiquitin oligomers to maltoheptaose en bloc, producing polyubiquitylated maltoheptaose in one catalytic step. The Sharpin and HOIP components of LUBAC, but not HOIL‐1, bound to unbranched and infrequently branched glucose polymers in vitro, but not to highly branched mammalian glycogen, suggesting a potential function in targeting HOIL‐1 to unbranched glucosaccharides in cells. We suggest that monoubiquitylation of unbranched glucosaccharides may initiate their removal from cells, preventing precipitation as polyglucosan

Deploying the NASA Valkyrie Humanoid for IED Response: An Initial Approach and Evaluation Summary

As part of a feasibility study, this paper shows the NASA Valkyrie humanoid robot performing an end-to-end improvised explosive device (IED) response task. To demonstrate and evaluate robot capabilities, sub-tasks highlight different locomotion, manipulation, and perception requirements: traversing uneven terrain, passing through a narrow passageway, opening a car door, retrieving a suspected IED, and securing the IED in a total containment vessel (TCV). For each sub-task, a description of the technical approach and the hidden challenges that were overcome during development are presented. The discussion of results, which explicitly includes existing limitations, is aimed at motivating continued research and development to enable practical deployment of humanoid robots for IED response. For instance, the data shows that operator pauses contribute to 50\% of the total completion time, which implies that further work is needed on user interfaces for increasing task completion efficiency.Comment: 2019 IEEE-RAS International Conference on Humanoid Robot

Resistance Exercise Reduces Skeletal Muscle Cachexia and Improves Muscle Function in Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a chronic, systemic, autoimmune, inflammatory disease associated with cachexia (reduced muscle and increased fat). Although strength-training exercise has been used in persons with RA, it is not clear if it is effective for reducing cachexia. A 46-year-old woman was studied to determine: (i) if resistance exercise could reverse cachexia by improving muscle mass, fiber cross-sectional area, and muscle function; and (2) if elevated apoptotic signaling was involved in cachexia with RA and could be reduced by resistance training. A needle biopsy was obtained from the vastus lateralis muscle of the RA subject before and after 16 weeks of resistance training. Knee extensor strength increased by 13.6% and fatigue decreased by 2.8% Muscle mass increased by 2.1%. Average muscle fiber cross-sectional area increased by 49.7%, and muscle nuclei increased slightly after strength training from 0.08 to 0.12 nuclei/μm2. In addition, there was a slight decrease (1.6%) in the number of apoptotic muscle nuclei after resistance training. This case study suggests that resistance training may be a good tool for increasing the number of nuclei per fiber area, decreasing apoptotic nuclei, and inducing fiber hypertrophy in persons with RA, thereby slowing or reversing rheumatoid cachexia