Adsorption of Cu, Ag, and Au atoms on graphene including van der Waals interactions

We performed a systematic density functional study of the adsorption of copper, silver, and gold adatoms on graphene, especially accounting for van der Waals interactions by the vdW-DF and the PBE+D2 methods. In particular, we analyze the preferred adsorption site (among top, bridge, and hollow positions) together with the corresponding distortion of the graphene sheet and identify diffusion paths. Both vdW schemes show that the coinage metal atoms do bind to the graphene sheet and that in some cases the buckling of the graphene can be significant. The results for silver are at variance with those obtained with GGA, which gives no binding in this case. However, we observe some quantitative differences between the vdW-DF and the PBE+D2 methods. For instance the adsorption energies calculated with the PBE+D2 method are systematically higher than the ones obtained with vdW-DF. Moreover, the equilibrium distances computed with PBE+D2 are shorter than those calculated with the vdW-DF method

LuxTrace: indoor positioning using building illumination

Tracking location is challenging due to the numerous constraints of practical systems including, but not limited to global cost, device volume and weight, scalability and accuracy; these constraints are typically more severe for systems that should be wearable and used indoors. We investigate the use of wearable solar cells to track changing light conditions (a concept that we named LuxTrace) as a source of user displacement and activity data. We evaluate constraints of this approach and present results from an experimental validation of displacement and activity estimation. The results indicate that a distance estimation accuracy of 21cm (80% quantile) can be achieved. A simple method to combine LuxTrace with complementary absolute location estimation methods is also presented. We apply carpet-like distributed RFID tags to demonstrate online learning of new lighting environment

Hydrogen site occupancy and strength of forces in nano-sized metal hydrides

The dipole force components in nano-sized metal hydrides are quantitatively determined with curvature and x-ray diffraction measurements. Ab-initio density functional theory is used to calculate the dipole components and the symmetry of the strain field. The hydrogen occupancy in a 100 nm thick V film is shown to be tetrahedral with a slight asymmetry at low concentration and a transition to octahedral occupancy is shown to take place at around 0.07 [H/V] at 360 K. When the thickness of the V layer is reduced to 3 nm and biaxially strained, in a Fe_0.5V_0.5/V superlattice, the hydrogen unequivocally occupies octahedral z-like sites, even at and below concentrations of 0.02 [H/V]

Privacy Rarely Considered: Exploring Considerations in the Adoption of Third-Party Services by Websites

Modern websites frequently use and embed third-party services to facilitate web development, connect to social media, or for monetization. This often introduces privacy issues as the inclusion of third-party services on a website can allow the third party to collect personal data about the website’s visitors. While the prevalence and mechanisms of third-party web tracking have been widely studied, little is known about the decision processes that lead to websites using third-party functionality and whether efforts are being made to protect their visitors' privacy. We report results from an online survey with 395 participants involved in the creation and maintenance of websites. For ten common website functionalities we investigated if privacy has played a role in decisions about how the functionality is integrated, if specific efforts for privacy protection have been made during integration, and to what degree people are aware of data collection through third parties. We find that ease of integration drives third-party adoption but visitor privacy is considered if there are legal requirements or respective guidelines. Awareness of data collection and privacy risks is higher if the collection is directly associated with the purpose for which the third-party service is used

Feasibility and cost description of highly intensive rehabilitation involving new technologies in patients with post-acute stroke-a trial of the Swiss RehabTech Initiative

BACKGROUND There is a need to provide highly repetitive and intensive therapy programs for patients after stroke to improve sensorimotor impairment. The employment of technology-assisted training may facilitate access to individualized rehabilitation of high intensity. The purpose of this study was to evaluate the safety and acceptance of a high-intensity technology-assisted training for patients after stroke in the subacute or chronic phase and to establish its feasibility for a subsequent randomized controlled trial. METHODS A longitudinal, multi-center, single-group study was conducted in four rehabilitation clinics. Patients participated in a high-intensity 4-week technology-assisted trainings consisting of 3 to 5 training days per week and at least 5 training sessions per day with a duration of 45 min each. Feasibility was evaluated by examining recruitment, intervention-related outcomes (adherence, subjectively perceived effort and effectiveness, adverse events), patient-related outcomes, and efficiency gains. Secondary outcomes focused on all three domains of the International Classification of Functioning Disability and Health. Data were analyzed and presented in a descriptive manner. RESULTS In total, 14 patients after stroke were included. Participants exercised between 12 and 21 days and received between 28 and 82 (mean 46 ± 15) technology-assisted trainings during the study period, which corresponded to 2 to 7 daily interventions. Treatment was safe. No serious adverse events were reported. Minor adverse events were related to tiredness and exertion. From baseline to the end of the intervention, patients improved in several functional performance assessments of the upper and lower extremities. The efficiency gains of the trainings amounted to 10% to 58%, in particular for training of the whole body and for walking training in severely impaired patients. CONCLUSIONS Highly intensive technology-assisted training appears to be feasible for in- and outpatients in the subacute or chronic phase after stroke. Further clinical trials are warranted in order to define the most comprehensive approach to highly intensive technology-assisted training and to investigate its efficacy in patients with neurological disorders. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT03641651 at August 31st 2018

An Autonomous Wearable System for Predicting and Detecting Localised Muscle Fatigue

Muscle fatigue is an established area of research and various types of muscle fatigue have been clinically investigated in order to fully understand the condition. This paper demonstrates a non-invasive technique used to automate the fatigue detection and prediction process. The system utilises the clinical aspects such as kinematics and surface electromyography (sEMG) of an athlete during isometric contractions. Various signal analysis methods are used illustrating their applicability in real-time settings. This demonstrated system can be used in sports scenarios to promote muscle growth/performance or prevent injury. To date, research on localised muscle fatigue focuses on the clinical side and lacks the implementation for detecting/predicting localised muscle fatigue using an autonomous system. Results show that automating the process of localised muscle fatigue detection/prediction is promising. The autonomous fatigue system was tested on five individuals showing 90.37% accuracy on average of correct classification and an error of 4.35% in predicting the time to when fatigue will onset

Feasibility and cost description of highly intensive rehabilitation involving new technologies in patients with post-acute stroke : a trial of the Swiss RehabTech Initiative

Background: There is a need to provide highly repetitive and intensive therapy programs for patients after stroke to improve sensorimotor impairment. The employment of technology-assisted training may facilitate access to individualized rehabilitation of high intensity. The purpose of this study was to evaluate the safety and acceptance of a high-intensity technology-assisted training for patients after stroke in the subacute or chronic phase and to establish its feasibility for a subsequent randomized controlled trial. Methods: A longitudinal, multi-center, single-group study was conducted in four rehabilitation clinics. Patients participated in a high-intensity 4-week technology-assisted trainings consisting of 3 to 5 training days per week and at least 5 training sessions per day with a duration of 45min each. Feasibility was evaluated by examining recruitment, intervention-related outcomes (adherence, subjectively perceived efort and efectiveness, adverse events), patient related outcomes, and efciency gains. Secondary outcomes focused on all three domains of the International Classifcation of Functioning Disability and Health. Data were analyzed and presented in a descriptive manner. Results: In total, 14 patients after stroke were included. Participants exercised between 12 and 21days and received between 28 and 82 (mean 46±15) technology-assisted trainings during the study period, which corresponded to 2 to 7 daily interventions. Treatment was safe. No serious adverse events were reported. Minor adverse events were related to tiredness and exertion. From baseline to the end of the intervention, patients improved in several functional performance assessments of the upper and lower extremities. The efciency gains of the trainings amounted to 10% to 58%, in particular for training of the whole body and for walking training in severely impaired patients. Conclusions: Highly intensive technology-assisted training appears to be feasible for in- and outpatients in the subacute or chronic phase after stroke. Further clinical trials are warranted in order to define the most comprehensive approach to highly intensive technology-assisted training and to investigate its efficacy in patients with neurological disorders