Engineering Commons^™

Extraction, Quantification, Characterization, And Application In Food Packaging Of Chitin And Chitosan From Mushrooms: A Review, Bullyamini Alimi, Shivani Pathania, Jude Wilson, Brendan Duffy, Jesus Maria Frias

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The application of chitin in food systems is limited by its insolubility in some common solvents and poor degradability. Hence, it is deacetylated to obtain chitosan, an industrially important derivative with excellent biological properties. Fungal-sourced chitosan is gaining prominence and industrial attraction because of its superior functional and biological properties, and vegan appeal. Further, the absence of such compounds as tropomyosin, myosin light chain, and arginine kinase, which are known to trigger allergic reactions, gives it an edge over marine-sourced chitosan in food and pharmaceutical applications. Mushrooms are macro-fungi with a significant content of chitin, with many authors reporting the …

High-Sensitivity Vector Bend Sensor Based On A Fiber Directional Coupler Inscribed By A Femtosecond Laser, Ke Tian, Mingyuan Zhang, Chuanzhein Zhao, Huibin Li, Shilong Li, Yuxuan Jiang, Gerald Farrell, Pengfei Wang

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In this Letter, we demonstrate a high-sensitivity vector bend sensor based on a fiber directional coupler. The fiber directional coupler is composed of two parallel waveguides inscribed within a no-core fiber (NCF) by a femtosecond laser. Since the two written waveguides have closely matched refractive indices and geometries, the transmission spectrum of the fiber directional coupler possesses periodic resonant dips. Such a fiber directional coupler exhibits a good bending-dependent spectral shift response due to its asymmetric structure. Experimental results show that bending sensitivities of -97.11 nm/m-1 and 58.22 nm/m-1 are achieved for the 0° and 180° orientations in the curvature …

A Label-Free Fiber Ring Laser Biosensor For Ultrahigh Sensitivity Detection Of Salmonella Typhimurium, Shi Qiu, Bin Liu, Yuankui Leng, Edward Fox, Xian Zhou, Binbin Yan, Xinzhu Sang, Long Long, Xingdao He, Jinhui Yuan, Gerald Farrell, Qiang Wu

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The rapid detection of low concentrations of Salmonella Typhimurium (S. Typhimurium) is an essential preventive measure for food safety and prevention of foodborne illness. The study presented in this paper addresses this critical issue by proposing a single mode-tapered seven core-single mode (STSS) fiber ring laser (FRL) biosensor for S. Typhimurium detection. The experimental results show that the specific detection time of S. Typhimurium is less than 20 min and the wavelength shift can achieve -0.906 nm for an S. Typhimurium solution (10 cells/mL). Furthermore, at a lower concentration of 1 cell/mL applied to the biosensor, a result of -0.183 …

Advances In 3d Culture Systems For Therapeutic Discovery And Development In Brain Cancer, Janith Wanigasekara, Patrick J. Cullen, Paula Bourke, Brijesh Tiwari, James F. Curtin

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This review focuses on recent advances in 3D culture systems that promise more accurate therapeutic models of the glioblastoma multiforme (GBM) tumor microenvironment (TME), such as the unique anatomical, cellular, and molecular features evident in human GBM. The key components of a GBM TME are outlined, including microbiomes, vasculature, extracellular matrix (ECM), infiltrating parenchymal and peripheral immune cells and molecules, and chemical gradients. 3D culture systems are evaluated against 2D culture systems and in vivo animal models. The main 3D culture techniques available are compared, with an emphasis on identifying key gaps in knowledge for the development of suitable platforms …

In-Flow Dynamics Of An Area-Difference-Energy Spring-Particle Red Blood Cell Model On Non-Uniform Grids, Brendan Walsh, Fergal Boyle

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In this paper the area-difference-energy spring-particle (ADE-SP) red blood cell (RBC) structural model developed by Chen and Boyle is coupled with a lattice Boltzmann flux solver to simulate RBC dynamics. The novel ADE-SP model accounts for bending resistance due to the membrane area difference of RBCs while the lattice Boltzmann flux solver offers reduced computational runtimes through GPU parallelisation and enabling the employment of non-uniform meshes. This coupled model is used to simulate RBC dynamics and predictions are compared with existing experimental measurements. The simulations successfully predict tumbling, tank-treading, swinging and intermittent behaviour of an RBC in shear flow, and …

A Step Closer To Elastogenesis On Demand; Inducing Mature Elastic Fibre Deposition In A Natural Biomaterial Scaffold, Francisco R. Almeida-González, Arlyng González-Vázquez, Suzanne M. Mithieux, Fergal J. O'Brien, Anthony S. Weiss, Claire Brougham

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Elastic fibres play a key role in bodily functions where fatigue resistance and elastic recovery are necessary while regulating phenotype, proliferation and migration in cells. While in vivo elastic fibres are created at a late foetal stage, a major obstacle in the development of engineered tissue is that human vascular smooth muscle cells (hVSMCs), one of the principal elastogenic cells, are unable to spontaneously promote elastogenesis in vitro. Therefore, the overall aim of this study was to activate elastogenesis in vitro by hVSMCs seeded in fibrin, collagen, glycosaminoglycan (FCG) scaffolds, following the addition of recombinant human tropoelastin. This combination …

Finite Element Simulation Of Head Impacts In Mixed Martial Arts, Stephen Tiernan, Aidan Meagher, David O'Sullivan Dr, Eoin O'Kelly Dr

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This study determined brain stress and strain in an unhelmeted sport and correlated this with concussive injuries. Thirteen MMA athletes were fitted with the MiG2.0 Stanford instrumented mouthguard. The mouthguard records linear acceleration and angular velocity in 6 degrees of freedom. Angular acceleration was calculated by differentiation. All events were video recorded, time stamped and reported impacts confirmed. 298 impacts above 10g were recorded during sparring sessions and 153 impacts in competitive events. The competitive events resulted in five concussions which were diagnosed by a medical doctor. The impact with the highest angular acceleration from each sparring session and competitive …

Concussion And The Severity Of Head Impacts In Mixed Martial Arts, Stephen Tiernan, Aidan Meagher, David O'Sullivan, Eoin O'Keefe, Eoin O'Kelly, Eugene Wallace, Colin Doherty, Mathew Campbell, Yuzhe Liu, August Domel

Articles

Background: Concern about the consequences of head impacts in US football motivated researchers to investigate and develop instrumentation to measure the severity of these impacts. However, the severity of head impacts in unhelmeted sports is largely unknown as miniaturised sensor technology has only recently made it possible to measure these impacts in vivo.

Aim: The objective of this study was to measure the linear and angular head accelerations in impacts in mixed martial arts (MMA), and correlate these with concussive injuries.

Methods: Thirteen MMA fighters were fitted with the Stanford instrumented mouthguard (MiG2.0). The mouthguard records linear acceleration and angular …

Comparison Of Hybridizing Options For Solar Heat, Biomass And Heat Storage For Electricity Generation In Spain, Cm Iftekhar Hussain, Brian Norton, Aidan Duffy

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Diurnal and seasonal variations of direct solar energy circumscribe locations suitable for sole use of concentrated solar power for electricity generation, whereas to generate electricity at night and during winter months, biomass systems can be used that incur fuel expenditures and may encounter fuel supply discontinuities. Combining solar heat, biomass conversion and heat storage in a hybrid electricity generation plant may overcome the limitations of sole use of any one of these energy sources in specific geographic and/or economic conditions. In this work standalone biomass, hybrid concentrated solar power-biomass and hybrid concentrated solar power-biomass-thermal energy storage power generation systems are …

Spectral Dependence Of Transmission Losses In High-Index Polymer Coated No-Core Fibers, Xiaokang Lian, Gerald Farrell, Qiang Wu, Wei Han, Changyu Shen, Youqiao Ma, Yuliya Semenova

Articles

A high-index polymer coated no-core fiber (PC-NCF) is effectively a depressed core fiber, where the light is guided by the anti-resonant, inhibited coupling and total internal reflection effects and the dispersion diagram shows periodic resonant and anti-resonant bands. In this paper, the transmission spectra of the straight and bent PC-NCFs (length > 5 cm) are measured and analyzed from a modal dispersion perspective. For the purpose of the study, the PC-NCFs are contained within a fiber hetero-structure using two single-mode fiber (SMF) pigtails forming a SMF-PC-NCF-SMF structure. The anti-resonance spectral characteristics are suppressed by the multimode interference in the PC-NCF with …

The Effect Of Impact Location On Brain Strain, Stephen Tiernan, Gary Byrne Mr

Articles

Objective: To determine the effect of impact direction on strains within the brain.

Research design: Laboratory drop tests of hybrid III head-form and finite element simulation of impacts.

Methods and procedures: A head-form instrumented with accelerometers and gyroscopes was dropped from 10 different heights in four orientations: front, rear, left and right hand side. Twelve impacts with constant impact energy were chosen to simulate, to determine the effect of impact location. A finite element head model was used to simulate these impacts, using 6 degrees of freedom. Following this a further set of simulations were performed, where the same acceleration …

Design And Development Of Artificial Spinal Ligaments For Paediatric Synthetic Spine, Nor Amalina Muhayudin, Khairul Salleh Basaruddin, Fiona Mcevoy, Anthony Tansey

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A synthetic spine is a model fabricated from artificial materials consisting of the vertebrae, intervertebral discs and ligaments for spinal testing. The synthetic spine overcomes many difficulties associated with biological specimens such as handling, biohazard concerns, high costs, and limited availability of specimens, quality and large inter-specimen variability. This paper presents the design and development of spinal ligaments to mimic the stiffness of the paediatric ligaments for use in the synthetic spine. Spinal ligaments are uniaxial structures in the spine that carry tensile loads along the direction of the fibres. Early in the research, silicone materials were used to cover …

Nanostructured Materials For Food Applications: Spectroscopy, Microscopy And Physical Properties, Shubham Sharma, Swana Jaiswal, Brendan Duffy, Amit Jaiswal

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Nanotechnology deals with the matter of atomic or molecular scale. Other factors that define the character of a nanoparticle are its physical and chemical properties, such as surface area, surface charge, hydrophobicity of the surface, the thermal stability of the nanoparticle, and its antimicrobial activity. A nanoparticle is usually characterized by using microscopic and spectroscopic techniques. Microscopic techniques are used to characterize the size, shape, and location of the nanoparticle by producing an image of the individual nanoparticle. Several techniques, such as scanning electron microscopy (SEM), transmission electron microscopy/high resolution transmission electron microscopy (TEM/HRTEM), atomic force microscopy (AFM) and scanning …

Nanostructured Apatite-Mullite Glass-Ceramics For Enhanced Primary Human Osteoblast Cell Response, Gordon Cooke, Conor Dunne, Sarah Keane, Daithi De Faoite, Seamas Donnelly, Kenneth Stanton

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This work investigates the difference in viability of primary human foetal osteoblast cells on a glass-ceramic surface with nanoscale topography relative to viability on a smooth glass-ceramic surface containing a bioactive phase. Apatite-mullite glass-ceramics containing bioactive fluorapatite (Ca₁₀(PO₄)₆F₂) and bioinert mullite (Si₂Al₆O₁₃) were synthesised and subsequent heat-treatment was optimised to form nano-sized fluorapatite crystals. Etching was used to selectively remove the bioactive phase, producing a surface with disordered nanoscale topography. Cells were seeded onto a smooth polished glass-ceramic substrate with the bioactive phase intact, an etched …

Freeze-Drying As A Novel Biofabrication Method For Achieving A Controlled Microarchitecture Within Large, Complex Natural Biomaterial Scaffolds, Claire Brougham, Tanya J. Levingstone, Nian Shen, Gerard M. Cooney, Thomas C. Flanagan, Stefan Jockenhoevel, Fergal J. O’Brien

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The biofabrication of large scaffolds from natural biomaterials into complex 3D shapes with controllable microarchitecture remains a major challenge. Freeze-drying (or lyophilization) is a technique used to create bioactive scaffolds with a porous architecture and is typically only used to generate scaffolds in planar 3D geometries. Here we report the development of a new biofabrication process to form a collagen-based scaffold into a large, complex geometry which has a large height to width ratio, and a controlled porous microarchitecture. This biofabrication process was validated through the successful development of a heart valve shaped scaffold, fabricated from a collagen-glycosaminoglycan co-polymer. Notably, …

An Enhanced Spring-Particle Model For Red Blood Cell Structural Mechanics: Application To The Stomatocyte–Discocyte– Echinocyte Transformation, Mingzhu Chen, Fergal Boyle

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Red blood cells (RBCs) are the most abundant cellular element suspended in blood. Together with the usual biconcave-shaped RBCs, i.e., discocytes, unusual-shaped RBCs are also observed under physiological and experimental conditions, e.g., stomatocytes and echinocytes. Stomatocytes and echinocytes are formed from discocytes and in addition can revert back to being discocytes; this shape change is known as the stomatocyte–discocyte–echinocyte (SDE) transformation. To-date, limited research has been conducted on the numerical prediction of the full SDE transformation. Spring- particle RBC (SP-RBC) models are commonly used to numerically predict RBC mechanics and rheology. However, these models are incapable of predicting the full …

Enhanced Corrosion Protection And Biocompatibility Of A Plga-Silane Coating On Az31 Mg Alloy For Orthopaedic Applications, Sankalp Agarwal, Muhammad Morshed, Marie-Noelle Labour, David Hoey, Brendan Duffy, James Curtin, Swarna Jaiswal

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This paper reports a multi-step procedure to fabricate a novel corrosion resistant and biocompatible PLGA-silane coating on the magnesium (Mg) alloy AZ31. The first step involves alkaline passivation followed by dip coating in a methyltriethoxysilane (MTES) and tetraethoxysilane (TEOS) mixture to produce a cross-linked siloxane coating. The second step is to impart an amine functionalization to the silane modified surface by using 3-aminopropyl-triethoxy silane (APTES) for promoting adhesion of the acid terminated poly-(lactic-co-glycolic) acid (PLGA) as a final coating step. Static contact angle measurements, Fourier transform infrared spectroscopy and scanning electron microscopy analysis confirmed the successful assembly of coatings on …

A Method To Calculate Adherence To Inhaled Therapy That Reflects The Changes In Clinical Features Of Asthma, Imran Sulaiman, Jansen Seheult, Elaine Machale, Fiona Boland, Susan M. O’Dwyer, Viliam Rapcan, Shona D’Arcy, Breda Cushen, Matshediso Mokoka, Isabelle Killane, Sheila A. Ryder, Richard B. Reilly, Richard W. Costello

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Electronic monitors are considered the gold standard for objectively quantifying adherence to inhaled therapy (1). Most studies using electronic recording devices have reported adherence as the mean adherence, or the mean daily dose, over the study period (2–4). However, this method does not reflect variations in the way that patients use their treatments. For example, the mean adherence is the same whether an individual took the medication according to the prescribed schedule or took all the doses in the first half of a dosing period, leaving none in the second half. Inhaler technique must …

Predicting Asthma Exacerbations Employing Remotely Monitored Adherence, Isabelle Killane, Imran Sulaiman, Elaine Mac Hale, Aoife Breathnach, Terrence Taylor, Martin Holmes, Richard B Reilly, Richard W Costello

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This Letter investigated the efficacy of a decision-support system, designed for respiratory medicine, at predicting asthma exacerbations in a multi-site longitudinal randomised control trial. Adherence to inhaler medication was acquired over 3 months from patients with asthma employing a dose counter and a remote monitoring adherence device which recorded participant's inhaler use: n = 184 (23,656 audio files), 61% women, age (mean ± sd) 49.3 ± 16.4. Data on occurrence of exacerbations was collected at three clinical visits, 1 month apart. The relative risk of an asthma exacerbation for those with good and poor adherence was examined employing a univariate …

A Protocol For A Randomised Clinical Trial Of The Effect Of Providing Feedback On Inhaler Technique And Adherence From An Electronic Device In Patients With Poorly Controlled Severe Asthma, Imran Sulaiman, Martin Holmes, Shona D'Arcy, Viliam Rapčan, Desmond Michael Murphy, Gloria Crispino, Isabelle Killane, Rw Costello, Richard B Reilly, Jansen Seheult, Gregory Diette, Elaine Machale, Terence Taylor

Articles

ntroduction In clinical practice, it is difficult to distinguish between patients with refractory asthma from those with poorly controlled asthma, where symptoms persist due to poor adherence, inadequate inhaler technique or comorbid diseases. We designed an audio recording device which, when attached to an inhaler, objectively identifies the time and technique of inhaler use, thereby assessing both aspects of adherence. This study will test the hypothesis that feedback on these two aspects of adherence when passed on to patients improves adherence and helps clinicians distinguish refractory from difficult-to-control asthma. Methods This is a single, blind, prospective, randomised, clinical trial performed …

Oxygen Mass Transport In Stented Coronary Arteries, Eoin Murphy, Adrian S. Dunne, David Martin, Fergal Boyle

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Oxygen deficiency, known as hypoxia, in arterial walls has been linked to increased intimal hyperplasia, which is the main adverse biological process causing in-stent restenosis. Stent implantation has significant effects on the oxygen transport into the arterial wall. Elucidating these effects is critical to optimizing future stent designs. In this study the most advanced oxygen transport model developed to date was assessed in two test cases and used to compare three coronary stent designs. Additionally, the predicted results from four simplified blood oxygen transport models are compared in the two test cases. The advanced model showed good agreement with experimental …

Self-Powered Microfluidic Device For Rapid Assay Of Antiplatelet Drugs, Bincy Jose, Peter Mccluskey, Niamh Gilmartin, Martin Somers, Dermot Kenny, Antonio J. Ricco, Nigel Kent, Lourdes Basabe-Desmonts

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We report the development of a microfluidic device for the rapid assay in whole blood of platelet-protein interactions indicative of the efficacy of antiplatelet drugs—e.g., aspirin and Plavix, two of the world’s most widely used drugs—in cardiovascular patients. Because platelet adhesion to surface-confined protein matrices is modulated by fluid shear rates at the blood/protein interface, and because such binding is a better indicator of platelet function than platelet self-aggregation, we designed, fabricated, and characterized the performance of a family of disposable, self-powered microfluidic chips with well-defined flow and interfacial shear rates suitable for small blood volumes (≤ 200 µL). We …

Incorporation Of Fibrin Into A Collagen–Glycosaminoglycan Matrix Results In A Scaffold With Improved Mechanical Properties And Enhanced Capacity To Resist Cell-Mediated Contraction, Claire Brougham, Tanya J. Levingstone, Stefan Jockenhoevel, Thomas C. Flanagan, Fergal J. O'Brien

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Fibrin has many uses as a tissue engineering scaffold, however many in vivo studies have shown a reduction in function resulting from the susceptibility of fibrin to cell-mediated contraction. The overall aim of the present study was to develop and characterise a reinforced natural scaffold using fibrin, collagen and glycosaminoglycan (FCG), and to examine the cell-mediated contraction of this scaffold in comparison to fibrin gels. Through the use of an injection loading technique, a homogenous FCG scaffold was developed. Mechanical testing showed a sixfold increase in compressive modulus and a thirtyfold increase in tensile modulus of fibrin when reinforced with …

Mattrack: A Matlab-Based Quantitative Image Analysis Platform For Investigating Real-Time Photo-Converted Fluorescent Signals In Live Cells, Jane Courtney, Elena Woods, Dimitri Scholz, William Hall, Virginie Gautier

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We introduce here MATtrack, an open source MATLAB-based computational platform developed to process multi-Tiff files produced by a photo-conversion time lapse protocol for live cell fluorescent microscopy. MATtrack automatically performs a series of steps required for image processing, including extraction and import of numerical values from Multi-Tiff files, red/green image classification using gating parameters, noise filtering, background extraction, contrast stretching and temporal smoothing. MATtrack also integrates a series of algorithms for quantitative image analysis enabling the construction of mean and standard deviation images, clustering and classification of subcellular regions and injection point approximation. In addition, MATtrack features a simple user …

Medical Device Software And Technology: The Past, Present And Future, Martin Mchugh

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No abstract provided.

Dual Effects Of Β-Cyclodextrin-Stabilised Silver Nanoparticles: Enhanced Biofilm Inhibition And Reduced Cytotoxicity, Swarna Jaiswal

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No abstract provided.

Breast Cancer Detection Using Interferometric Music: Experimental And Numerical Assessment, Giuseppe Ruvio, Raffaele Solimene, Antonio Cuccaro, Domenico Gaetano, Jacinta Browne, Max Ammann

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Purpose: In microwave breast cancer detection, it is often beneficial to arrange sensors in close proximity to the breast. The resultant coupling generally changes the antenna response. As an a priori characterization of the radio frequency system becomes difficult, this can lead to severe degradation of the detection efficacy. The purpose of this paper is to demonstrate the advantages of adopting an interferometric multiple signal classification (I-MUSIC) approach due to its limited dependence from a priori information on the antenna. The performance of I-MUSIC detection was measured in terms of signal-to-clutter ratio (SCR), signal-to-mean ratio (SMR), and spatial displacement (SD) …

Investigation Of Membrane Mechanics Using Spring Networks: Application To Red-Blood-Cell Modelling, Mingzhu Chen, Fergal Boyle

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In recent years a number of red-blood-cell (RBC) models have been proposed using spring networks to represent the RBC membrane. Some results predicted by these models agree well with experimental measurements. How- ever, the suitability of these membrane models has been questioned. The RBC membrane, like a continuum mem- brane, is mechanically isotropic throughout its surface, but the mechanical properties of a spring network vary on the network surface and change with deformation. In this work spring-network mechanics are investigated in large deformation for the first time via an assessment of the effect of network parameters, i.e. network mesh, spring …

Field Penetration In Mri-Based Breast Models: A Numerical Investigation, Giuseppe Ruvio, Raffaele Solimene, Antonio Cuccaro, Max Ammann

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The use of reliable computational tools is fundamental to investigate different aspects of microwave breast cancer imaging. From the development of high-definition and realistic numerical breast models, different coupling mechanisms and the reaction of different tissues to microwave signals can be characterized. In this paper, field penetration inside four numerical breast phantoms with varying adipose content is evaluated in the frequency range 0.5 - 10 GHz across sagittal cuts.

A Method To Assess Adherence In Inhaler Use Through Analysis Of Acoustic Recordings Of Inhaler Events, Shona D’Arcy, Elaine Machale, Jansen Seheult, Martin S. Holmes, Cian Hughes, Imran Sulaiman, Deirdre Hyland, Conor O’Reilly, Senan Glynn, Thekra Al-Zaabi, John Mccourt, Terence Taylor, Frank Keane, Isabelle Killane, Richard B. Reilly, Richard W. Costello

Articles

Rationale: Poor adherence to inhaler use can be due to poor temporal and/or technique adherence. Up until now there has been no way of reliably tracking both these factors in everyday inhaler use. Objectives: This paper introduces a device developed to create time stamped acoustic recordings of an individual’s inhaler use, in which empirical evidence of temporal and technique adherence in inhaler use can be monitored over time. The correlation between clinical outcomes and adherence, as determined by this device, was compared for temporal adherence alone and combined temporal and technique adherence. Findings: The technology was validated by showing that …