Improving Caregiver Health through Systematic Assessment and a Tailored Plan of Care

Caregivers often experience strain and negative effects on their well-being. We tested the effects of a caregiver assessment and tailored care plan for caregivers of patients transitioning home from an inpatient rehabilitation facility (IRF), a study involving two groups: usual care ( n = 225) (preimplementation) and intervention (postimplementation) ( n = 215). Caregivers in the intervention group were assessed using the 25-item self-reported Preparedness Assessment for the Transition Home during the IRF stay. A tailored care plan was implemented in response to the assessment. Caregivers in both groups completed the Modified Caregiver Strain Index and Global Health Scale at 30- and 90-day postdischarge. After adjusting for baseline and demographics, caregivers in the intervention group reported lower strain ( p < .01) and better overall health ( p < .05) at 30-day post-IRF discharge, relative to usual care. Implementing a systematic caregiver assessment and tailored care plan in the IRF may mitigate the adverse effects of caregiving.

Behavior of Elastic Therapeutic Tapes under Dynamic and Static Conditions

The aim of this paper is to determine the relaxation behavior of the therapeutic tape under different thermomechanical conditions over different time spans and to analyze the physical and mechanical properties of selected kinesiology tapes. The relaxation test was conducted under a static condition with two extended levels (25% and 50%) for one hour and a dynamic condition for 300 cycles with different loading-unloading values, strain rates, and temperatures. For both static and dynamic conditions, at a lower strain rate and higher load and temperature, the therapeutic tapes showed higher loss of internal stress and faster losses of efficiency. Under all selected conditions, the tape’s stress has decreased rapidly.

Comprehensive Echocardiography of Left Atrium and Left Ventricle Using Modern Techniques Helps in Better Revealing Atrial Fibrillation in Patients with Hypertrophic Cardiomyopathy

Atrial fibrillation (AF) is an important arrhythmia in hypertrophic cardiomyopathy (HCM). We aimed to explore whether a complex evaluation of the left ventricle (LV) using modern echocardiography techniques, in addition to the left atrium (LA boosts), could improved the probability of AF diagnosis. Standard echocardiography, 2D and 3D speckle tracking, were performed for LA and LV evaluation in HCM patients and healthy volunteers. Of 128 initially qualified HCM patients, 60 fulfilled included criteria, from which 43 had a history of AF, and 17 were without AF. LA volume index and peak strain, LV ejection fraction, and strains were significant predictors of AF. In addition, 2D global longitudinal strain (GLS) for LV at cut off −16% turned out to be the most accurate predictor of AF (OR 48.00 [95% CI 2.68–859.36], p = 0.001), whereas the combination of LA peak strain ≤ 22% and LV GLS ≥ −16% had the highest discriminatory power (OR 76.36 [95% CI 4.13–1411.36], p = 0.001). AF in HCM patients seems to be LA as well as LV disease. Revealing lower strain for LV, in addition to lower LA strain, may have an important impact on accurate characteristics of HCM patients with AF history.

Comparative Study of Plasma Cladded Fe-Based Composite Hardfacings with In Situ Synthesized Cr and Ti Carbide Reinforcement

This study aimed to compare the X3CrNiMo17-13-3 stainless steel based plasma transferred arc (PTA) cladded hardfacings, reinforced with the in-situ synthesized Cr and Ti carbides. Carbon black and either pure Cr, pure Ti, or TiO2 were utilized as reinforcement precursors (the respective hardfacings are further referred to as Cr+C, Ti+C and TiO2+C). The pre-placed mixtures of matrix and reinforcement precursor powders were remelted by the plasma transferred arc, applying the preliminarily optimized process parameters (95 A, 22 – 24 V, 0.2 mm/s). As a reference, the unreinforced stainless steel hardfacing was used. The carbide reinforcement was successfully in-situ synthesized in all the hardfacings. The Cr + C hardfacing exhibited the largest average hardness (556 ± 29 HV1), while the TiO2 + C hardfacing had the largest average Young’s modulus (156.3 ± 19.7 GPa). The Cr + C and Ti + C hardfacings demonstrated the 2.3 and 2.1 times higher resistance to abrasive wear than the reference hardfacing. The TiO2 + C hardfacing showed 1.5 times lower wear resistance than the reference hardfacing presumably due to a lack of the reinforcement and a lower strain hardening ability.

Effect of Stretching Rate on Tensile Response and Crystallization Behavior of Crosslinked Natural Rubber

The performance of natural rubber (NR) relies heavily on the microstructural changes during deformation. This has brought to significant change in the stress response of NR. Besides, the stretching rate may also affect the stress response of NR. In this study, effects of stretching rate on tensile deformation and strain-induced crystallization of crosslinked NR were investigated. Results indicated that increasing the strain rate has increased the stress at given strain where the onset of strain-induced crystallization was shifted to a lower strain. The crystallinity of the crosslinked NR was shown to be higher at a high stretching rate and it corresponded well with the tensile response. The results clearly confirm that chain orientation and crystallization became stronger with increasing deformation rate. The study also suggests that the deformation could improve distribution of crosslinked network structures.

Elucidating Axonal Injuries Through Molecular Modelling of Myelin Sheaths and Nodes of Ranvier

Around half of the traumatic brain injuries are thought to be axonal damage. Disruption of the cellular membranes, or alternatively cytoskeletal damage has been suggested as possible injury trigger. Here, we have used molecular models to have a better insight on the structural and mechanical properties of axon sub-cellular components. We modelled myelin sheath and node of Ranvier as lipid bilayers at a coarse grained level. We built ex-novo a model for the myelin. Lipid composition and lipid saturation were based on the available experimental data. The model contains 17 different types of lipids, distributed asymmetrically between two leaflets. Molecular dynamics simulations were performed to characterize the myelin and node-of-Ranvier bilayers at equilibrium and under deformation and compared to previous axolemma simulations. We found that the myelin bilayer has a slightly higher area compressibility modulus and higher rupture strain than node of Ranvier. Compared to the axolemma in unmyelinated axon, mechanoporation occurs at 50% higher strain in the myelin and at 23% lower strain in the node of Ranvier in myelinated axon. Combining the results with finite element simulations of the axon, we hypothesizes that myelin does not rupture at the thresholds proposed in the literature for axonal injury while rupture may occur at the node of Ranvier. The findings contribute to increases our knowledge of axonal sub-cellular components and help to understand better the mechanism behind axonal brain injury.

MECHANICAL BEHAVIOR AND MICROSTRUCTURE EVOLUTION OF THE Ti-3Al-5Mo-4.5V ALLOY AT AN ELEVATED DEFORMATION TEMPERATURE

A high-performance titanium alloy requires a fine and homogenous microstructure. The rational deformation process parameters of the Ti-3Al-5Mo-4.5V (TC16) titanium alloy can contribute to achieving this important microstructure. Hot-compression experiments were performed at temperatures in the range 100–800 °C and at strain rates of 0.1 s–1 to 10.0 s–1. The effects of deformation temperatures and deformation rates on the mechanical behaviour and microstructure evolution were analysed and discussed. The softening mechanism of the Ti-3Al-5Mo-4.5V alloy at an elevated deformation temperature was revealed. Experimental results showed that 500 °C is the critical deformation temperature to distinguish the warm-deformation region of 100–400 °C and the hot-deformation region of 500–800 °C. The softening mechanism is dominated by -phase spheroidization in the temperature range 100–400 °C with a higher strain rate of 10.0 s–1. The softening mechanism is dominated by a local temperature rise in the temperature range 500–800 °C with a lower strain rate of 0.1 s–1.

FE Model Of A Cord-Rubber Railway Brake Tube Subjected To Extreme Operational Loads On A Reverse Curve Test Track

In certain cases, rolling stocks and railway vehicle components, i.e. brake tubes need to operate under extreme conditions such as at sub-zero temperature (e.g. -40°C) and on a reverse curve track, when displacements of the suspension points of the tubes cause large deformations in tubes. In this paper, displacements of the suspension points of the tubes are determined by a kinematic model validated by a draw and buffing gear test [1]. Afterwards, FE simulation has been carried out at minimum and maximum suspension point distance based on these displacements for the investigation of stress, strain states and possible failure considering the case of internal pressure and no internal pressure. Equivalent strain, stress and Tsai-Hill failure indices are much below the criterial values, so failure is not probable. The straight section between the curves of opposite curvatures reduces deformation in tubes in the critical positions leading to lower strain, stress and failure index values.

Fabrication of GaN nano-towers based self-powered UV photodetector

The fabrication of unique taper-ended GaN-Nanotowers structure based highly efficient ultraviolet photodetector is demonstrated. Hexagonally stacked, single crystalline GaN nanocolumnar structure (nanotowers) grown on AlN buffer layer exhibits higher photocurrent generation due to high quality nanotowers morphology and increased surface/volume ratio which significantly enhances its responsivity upon ultraviolet exposure leading to outstanding performance from the developed detection device. The fabricated detector display low dark current (~ 12 nA), high ILight/IDark ratio (> 104), fast time-correlated transient response (~ 433 µs) upon ultraviolet (325 nm) illumination. A high photoresponsivity of 2.47 A/W is achieved in self-powered mode of operation. The reason behind such high performance could be attributed to built-in electric field developed from a difference in Schottky barrier heights will be discussed in detail. While in photoconductive mode, the responsivity is observed to be 35.4 A/W @ − 3 V along with very high external quantum efficiency (~ 104%), lower noise equivalent power (~ 10–13 WHz−1/2) and excellent UV–Vis selectivity. Nanotower structure with lower strain and dislocations as well as reduced trap states cumulatively contributed to augmented performance from the device. The utilization of these GaN-Nanotower structures can potentially be useful towards the fabrication of energy-efficient ultraviolet photodetectors.

Mechanical properties of wrought magnesium alloys

Lightweight magnesium alloys are being increasingly used in automotive and other transportation industries to achieve energy efficiency. The objective of this thesis was to study the mechanical properties of two wrought alloys AZ31 and AM30. With increasing strain rate the yield strength and ultimate tensile strength increased and the strain hardening exponent decreased for AM30 and increased for AZ31. Both alloys exhibited stable cyclic characteristics at lower strain amplitudes and cyclic hardening characteristics at higher strain amplitudes. The Bauschinger effect was pronounced at higher strain amplitudes, resulting in asymmetric hysteresis loops in both alloys. The influence of strain ratio (Rs), strain rate, and initial straining direction on the cyclic deformation characteristics and fatigue life was evaluated. At low Rs, both alloys exhibited strong cyclic hardening, which decreased as Rs increased. Fatigue crack initiation was observed to occur from the specimen surface and crack propagation was basically characterized by striation-like features.