Life Is Like a Salad Bowl (or Should Be!)

Everyone in the world eats salad of some sort. We enjoy all the different ingredients in our salads depending on what we have a taste for at the time

Automatic identification of gait events using an instrumented sock

Background: textile-based transducers are an emerging technology in which piezo-resistive properties of materials are used to measure an applied strain. By incorporating these sensors into a sock, this technology offers the potential to detect critical events during the stance phase of the gait cycle. This could prove useful in several applications, such as functional electrical stimulation (FES) systems to assist gait. Methods: we investigated the output of a knitted resistive strain sensor during walking and sought to determine the degree of similarity between the sensor output and the ankle angle in the sagittal plane. In addition, we investigated whether it would be possible to predict three key gait events, heel strike, heel lift and toe off, with a relatively straight-forward algorithm. This worked by predicting gait events to occur at fixed time offsets from specific peaks in the sensor signal. Results: our results showed that, for all subjects, the sensor output exhibited the same general characteristics as the ankle joint angle. However, there were large between-subjects differences in the degree of similarity between the two curves. Despite this variability, it was possible to accurately predict gait events using a simple algorithm. This algorithm displayed high levels of trial-to-trial repeatability. Conclusions: this study demonstrates the potential of using textile-based transducers in future devices that provide active gait assistance

Simulation of wind-diesel hybrid power system for a rural community in Nigeria

This paper presents a Wind-and-Diesel Hybrid power system to be sited at Abonnema, a community located in the suburb of Port Harcourt, Rivers State of Nigeria (latitude 4.71N, longitude 6.79E).This was achieved through five phases of work: a wind resource assessment was undertaken using Weibull probability distribution; an optimal wind turbine blade was designed applying the tip-loss model approach; the hybrid system was sized; Simulation using MATLAB® programme were performed on the hybrid power system; and an economic analysis was conducted on the system adopting the life cycle cost method. The results obtained on the wind data analysis showed that even at a high hub height, the wind speed of Port Harcourt zone is low. The simulation results obtained shows that wind-and-diesel hybrid power system with battery storage can be operated suitably to obtain a more reliable power supply as well as improve fuel savings. Economic analysis conducted shows the positive benefits of implementing the hybrid wind-and-diesel power system rather than continuing with the existing diesel power plant over the project life cycle of 20 years.Keywords: Wind power, diesel generator, hybrid power, design and simulation of power system

Lived experiences of informal caregivers of people with chronic musculoskeletal pain: a systematic review and meta-ethnography

BACKGROUND: People with chronic pain often seek support from friends and family for everyday tasks. These individuals are termed informal caregivers. There remains uncertainty regarding the lived experiences of these people who care for individuals with chronic musculoskeletal pain. The aim of this paper is to synthase the evidence on the lived experiences of informal caregivers providing care to people with chronic musculoskeletal pain. METHODS: A systematic literature review was undertaken of published and unpublished literature databases including: EMBASE, MEDLINE, CINAHL, PubMed, the WHO International Clinical Trial Registry and ClinicalTrials.gov registry (to September 2019). Qualitative studies exploring the lived experiences of informal caregivers of people with chronic musculoskeletal pain were included. Data were synthesised using a meta-ethnography approach. Evidence was evaluated using the Critical Appraisal Skills Programme (CASP) qualitative appraisal tool. RESULTS: From 534 citations, 10 studies were eligible (360 participants: 171 informal caregivers of 189 care recipients). The evidence was moderate quality. Seven themes arose: the relationship of caregivers to healthcare professionals, role reversal with care recipients; acting the confidant to the care recipient; a constant burden in caregiving; legitimising care recipient’s condition; knowledge and skills to provide caregiving; and the perception of other family members and wider-society to the caregiver/care recipient dyad. CONCLUSIONS: The lived experiences of caregivers of people with chronic musculoskeletal pain is complex and dynamic. There is an inter-connected relationship between caregivers, care recipients and healthcare professionals. Exploring how these experiences can be modified to improve a caregiving dyad’s lived experience is now warranted

On plane gravitational waves in real connection variables

We investigate using plane fronted gravitational wave space-times as model systems to study loop quantization techniques and dispersion relations. In this classical analysis, we start with planar symmetric space-times in the real connection formulation. We reduce via Dirac constraint analysis to a final form with one canonical pair and one constraint, equivalent to the metric and Einstein equations of plane-fronted with parallel rays waves. Due to the symmetries and use of special coordinates general covariance is broken. However, this allows us to simply express the constraints of the consistent system. A recursive construction of Dirac brackets results in non-local brackets, analogous to those of self-dual fields, for the triad variables chosen in this approach.Comment: v2: Matches published version, up to minor stylistic change

Design and Construction of A 50kg Capacity Furnace

The design and development of a 50Kg charcoal fired crucible furnace for melting aluminium and its alloys are presented. Importance of Metal melting furnaces cannot be overemphasized in industrialized and under industrialized countries. A detailed designed analysis was conducted to determine the various component sizes of the crucible furnace so to pave way for its construction. Majority of the materials used for the furnace construction were obtained locally. The blower capacity was determined to be air to ratio of 400:1 and 0.05m3/min. The designed furnace of overall volumetric capacity of 0.57m3 accommodates a crucible pot which had a height and volume of 0.577m and 0.0155m3 respectively. The designed operating temperature of the furnace was 1200oC and maintained a heat transfer rate of 494.2W/m2 across the wall. The designed efficiency of the charcoal fired furnace was 59.35%. Keywords: Crucible, furnace, Charcoal, Volumetric capacity, Design, Efficiency DOI: 10.7176/ISDE/12-2-03 Publication date: April 30th 202

Numerical evaluation of singular integrals on non-disjoint self-similar fractal sets

We consider the numerical evaluation of a class of double integrals with respect to a pair of self-similar measures over a self-similar fractal set (the attractor of an iterated function system), with a weakly singular integrand of logarithmic or algebraic type. In a recent paper (Gibbs et al. Numer. Algorithms 92, 2071–2124 2023), it was shown that when the fractal set is “disjoint” in a certain sense (an example being the Cantor set), the self-similarity of the measures, combined with the homogeneity properties of the integrand, can be exploited to express the singular integral exactly in terms of regular integrals, which can be readily approximated numerically. In this paper, we present a methodology for extending these results to cases where the fractal is non-disjoint but non-overlapping (in the sense that the open set condition holds). Our approach applies to many well-known examples including the Sierpinski triangle, the Vicsek fractal, the Sierpinski carpet, and the Koch snowflake

Biomechanical properties of the thin PVD coatings defined by red blood cells

The measurement of the strength of bonds between biomaterials and cells is a major challenge in biotribology since it allows for the identification of different species in adhesion phenomena. Biomaterials, such as diamond-like carbon (DLC), titanium, and titanium nitride, seem to be good candidates for future blood-contact applications. These materials were deposited as thin films by the hybrid pulsed laser deposition (PLD) technique to examine the influence of such surfaces on cell behavior. The biomaterial examinations were performed in static conditions with red blood cells and then subjected to a dynamical test to observe the cell detachment kinetics. The tests revealed differences in behavior with respect to the applied coating material. The strongest cell-biomaterial interaction was observed for the carbonbased materials compared to the titanium and titanium nitride. Among many tests, a radial flow interaction analysis gives the opportunity to analyze cell adhesion to the applied material with the high accuracy. Analysis of concentrates helped to select materials for further dynamic tests on blood using an aortic flow simulator. In this case, the platelet adhesion to the surface and their degree of activation was analyzed. The quality of the selected coating was tested using a scratch test. The analyses of the microstructure were done using high resolution transmission electron microscopy. The phase composition and the residual stress were analyzed using X-ray diffraction methods