Strain-engineered manufacturing of freeform carbon nanotube microstructures.

The skins of many plants and animals have intricate microscale surface features that give rise to properties such as directed water repellency and adhesion, camouflage, and resistance to fouling. However, engineered mimicry of these designs has been restrained by the limited capabilities of top-down fabrication processes. Here we demonstrate a new technique for scalable manufacturing of freeform microstructures via strain-engineered growth of aligned carbon nanotubes (CNTs). Offset patterning of the CNT growth catalyst is used to locally modulate the CNT growth rate. This causes the CNTs to collectively bend during growth, with exceptional uniformity over large areas. The final shape of the curved CNT microstructures can be designed via finite element modeling, and compound catalyst shapes produce microstructures with multidirectional curvature and unusual self-organized patterns. Conformal coating of the CNTs enables tuning of the mechanical properties independently from the microstructure geometry, representing a versatile principle for design and manufacturing of complex microstructured surfaces.This is the author accepted manuscript. The final published version can be found in Nature Communications here: http://www.nature.com/ncomms/2014/140729/ncomms5512/full/ncomms5512.html. This paper will be under embargo until 29/1/15

Electrothermal Icing Protection of Aerosurfaces Using Conductive Polymer Nanocomposites

Ice protection systems (IPS) are critical components for many aerospace flight vehicles, including commercial transports and unmanned aerial systems (UAS), and can include anti-icing, de-icing, ice sensing, etc. Here, an IPS is created using nanomaterials to create a surface-modified external layer on an aerosurface based on observations that polymer nanocomposites have tailorable and attractive heating properties. The IPS uses Joule heating of aligned carbon nanotube (CNT) arrays to create highly efficient de-icing and anti-icing of aerosurfaces. An ice wind tunnel test of a CNT enhanced aerosurface is performed to demonstrate the system under a range of operating regimes (temperature, wind speed, water content in air) including operation down to -20.6°C (-5°F) at 55.9 m/s (125 mph) under heavy icing. Manufacturing, design considerations, and further improvements to the materials and systems are discussed.United States. Dept. of the Navy. Small Business Innovation Research (Contract N68335-11-C-0424)National Science Foundation (U.S.). Materials Research Science and Engineering Centers (Program) (Grant DMR-0819762

A telephone reminder to enhance adherence to interventions in cardiovascular randomized trials: A protocol for a study within a trial (SWAT)

This is the peer reviewed version of the following article: Bensaaud, A, Gibson, I, Jones, J, et al. A telephone reminder to enhance adherence to interventions in cardiovascular randomized trials: A protocol for a study within a trial (SWAT). J Evid Based Med. 2020; 13: 81– 84., which has been published in final form at https://doi.org/10.1111/jebm.12375. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.School of Nursing and Midwifery, the NationalUniversity of Ireland Galwa

The effect of lifestyle and risk factor modification on occlusive peripheral arterial disease outcomes: standard healthcare vs structured programme—for a randomised controlled trial protocol

© The Author(s) 2021. Background: Peripheral arterial disease (PAD) affects more than 200 million of the global population. PAD represents a marker for premature cardiovascular events. Patients with PAD, even in the absence of a history of myocardial infarction or ischemic stroke, have approximately the same relative risk of death from cardiovascular causes as patients with a history of coronary or cerebrovascular disease. Despite the high prevalence of PAD and the strong association with cardiovascular morbidity and mortality, patients with PAD are less likely to receive appropriate treatment for their atherosclerotic risk factors than those who are being treated for coronary artery disease. Atherosclerotic risk factor identification and modification play an important role in reducing the number of adverse outcomes among patients with atherosclerosis. Risk reduction therapy decreases the risk of cardiovascular mortality and morbidity in patients with PAD. In this study, we aim to evaluate the effectiveness of a lifestyle and risk factor modification intervention programme in achieving treatment goals for PAD risk factors. Methods: This is a randomised, parallel group, active-control trial to compare the effectiveness of the risk factor modification intervention programme to standard healthcare in a tertiary vascular care centre, in the reduction of modified risk factors in PAD patients. The primary outcome of this study is to evaluate the effectiveness of a lifestyle and risk factor modification intervention programme in achieving treatment goals for PAD risk factors at 3 and 12 months. The secondary outcomes are to compare the impact of the programme on clinical outcomes in PAD patients at 12 months. Secondary outcomes include amputation-free survival, clinical improvement, haemodynamic improvement, need for revascularisation procedures, outcomes of revascularisation procedures, changes in quality of life and the incidence of adverse events. Discussion: This study will provide clear evidence on the effectiveness of a lifestyle and risk factor modification intervention programme in achieving treatment goals for PAD risk factors, through a high-quality, well-powered clinical trial. Trial registration: This trial was registered (11/07/2017) on the European Clinical Trials Database (EudraCT number 2017-002964-41) and ClinicalTrials.gov (NCT03935776) which was registered on 02 May 2019.Ministry of Higher Education and Scientific Research, Libyan Embassy medical doctorate scholarshi

Fabrication and electrical integration of robust carbon nanotube micropillars by self-directed elastocapillary densification

Vertically-aligned carbon nanotube (CNT) "forest" microstructures fabricated by chemical vapor deposition (CVD) using patterned catalyst films typically have a low CNT density per unit area. As a result, CNT forests have poor bulk properties and are too fragile for integration with microfabrication processing. We introduce a new self-directed capillary densification method where a liquid is controllably condensed onto and evaporated from CNT forests. Compared to prior approaches, where the substrate with CNTs is immersed in a liquid, our condensation approach gives significantly more uniform structures and enables precise control of the CNT packing density and pillar cross-sectional shape. We present a set of design rules and parametric studies of CNT micropillar densification by this method, and show that self-directed capillary densification enhances the Young's modulus and electrical conductivity of CNT micropillars by more than three orders of magnitude. Owing to the outstanding properties of CNTs, this scalable process will be useful for the integration of CNTs as functional material in microfabricated devices for mechanical, electrical, thermal, and biomedical applications

Does topical wound oxygen (two2) offer an improved outcome over conventional compression dressings (ccd) in the management of refractory venous ulcers (rvu)? a parallel observational comparative study

AbstractObjectivesTopical wound oxygen (TWO2) may help wound healing in the management of refractory venous ulcers (RVU). The aim of this study was to measure the effect of TWO2 on wound healing using the primary end-point of the proportion of ulcers healed at 12 weeks. Secondary end-points were time to full healing, percentage of reduction in ulcer size, pain reduction, recurrence rates and Quality-Adjusted Time Spent Without Symptoms of disease and Toxicity of Treatment (Q-TWiST).DesignA parallel observational comparative study.MethodsPatients with CEAP C6,s RVU, assessed by duplex ultrasonography, were managed with either TWO2 (n=46) or conventional compression dressings (CCD) (n=37) for 12 weeks or till full healing. Patients were followed up at 3 monthly intervals.ResultsAt 12 weeks, 80% of TWO2 managed ulcers were completely healed, compared to 35% of CCD ulcers (p<0.0001). Median time to full healing was 45 days in TWO2 patients and 182 days in CCD patients (p<0.0001). The pain score threshold in TWO2 managed patients improved from 8 to 3 by 13 days. After 12-month follow-up, 5 of the 13 healed CCD ulcers showed signs of recurrence compared to none of the 37 TWO2 healed ulcers. TWO2 patients experienced a significantly improved Q-TWiST.ConclusionTWO2 reduces recurrence rates, alleviates pain and improves the Q-TWiST. We believe it is a valuable tool in the armamentarium of management of RVU

Controlled growth orientation of carbon nanotube pillars by catalyst patterning in microtrenches

We present a novel method for controlling the growth orientation of individual carbon nanotube (CNT) microstructures on a silicon wafer substrate. Our method controls the CNT forest orientation by patterning the catalyst layer used in the CNTs growth on slanted KOH edges. The overlap of catalyst area on the horizontal bottom and sloped sidewall surfaces of the KOH-etched substrate enables precise variation of the growth direction. These inclined structures can profit from the outstanding mechanical, electrical, thermal, and optical properties of CNTs and can therefore improve the performance of several MEMS devices. Inclined CNT microstructures could for instance be used as cantilever springs in probe card arrays, as tips in dip-pen lithography, and as sensing element in advanced transducers. ©2009 IEEE