scholarly journals The Micro Topology and Statistical Analysis of the Forces of Walking and Failure of an ITAP in a Femur

Micromachines ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 298
Author(s):  
Euan Langford ◽  
Christian Andrew Griffiths ◽  
Andrew Rees ◽  
Josh Bird
Keyword(s):  
Local Maximum ◽  
Topology Analysis ◽  
Extreme Loads ◽  
Wide Range ◽  
Physical Testing ◽  
Critical Materials ◽  
Layer Manufacture ◽  
Improve Patient ◽  
Maximum Stresses ◽  
Excessive Stress

This paper studies the forces acting upon the Intraosseous Transcutaneous Amputation Prosthesis, ITAP, that has been designed for use in a quarter amputated femur. To design in a failure feature, utilising a safety notch, which would stop excessive stress, σ, permeating the bone causing damage to the user. To achieve this, the topology of the ITAP was studied using MATLAB and ANSYS models with a wide range of component volumes. The topology analysis identified critical materials and local maximum stresses when modelling the applied loads. This together with additive layer manufacture allows for bespoke prosthetics that can improve patient outcomes. Further research is needed to design a fully functional, failure feature that is operational when extreme loads are applied from any direction. Physical testing is needed for validation of this study. Further research is also recommended on the design so that the σ within the ITAP is less than the yield stress, σs, of bone when other loads are applied from running and other activities.

scholarly journals Cochlear Implant Research and Development in the Twenty-first Century: A Critical Update

2021 ◽  
Vol 22 (5) ◽  
pp. 481-508
Author(s):  
Robert P. Carlyon ◽  
Tobias Goehring
Keyword(s):  
Research And Development ◽  
Patient Outcomes ◽  
Speech Processing ◽  
Turn Of The Century ◽  
First Century ◽  
Directional Microphones ◽  
Wide Range ◽  
The Subject ◽  
Processing Algorithms ◽  
Improve Patient

AbstractCochlear implants (CIs) are the world’s most successful sensory prosthesis and have been the subject of intense research and development in recent decades. We critically review the progress in CI research, and its success in improving patient outcomes, from the turn of the century to the present day. The review focuses on the processing, stimulation, and audiological methods that have been used to try to improve speech perception by human CI listeners, and on fundamental new insights in the response of the auditory system to electrical stimulation. The introduction of directional microphones and of new noise reduction and pre-processing algorithms has produced robust and sometimes substantial improvements. Novel speech-processing algorithms, the use of current-focusing methods, and individualised (patient-by-patient) deactivation of subsets of electrodes have produced more modest improvements. We argue that incremental advances have and will continue to be made, that collectively these may substantially improve patient outcomes, but that the modest size of each individual advance will require greater attention to experimental design and power. We also briefly discuss the potential and limitations of promising technologies that are currently being developed in animal models, and suggest strategies for researchers to collectively maximise the potential of CIs to improve hearing in a wide range of listening situations.

LATTICE DYNAMICS OF THE BINARY APERIODIC CHAINS OF ATOMS I: FRACTAL DIMENSION OF PHONON SPECTRA

1995 ◽  
Vol 09 (12) ◽  
pp. 1429-1451 ◽  
Author(s):  
WŁODZIMIERZ SALEJDA
Keyword(s):  
Fractal Dimension ◽  
Lattice Dynamics ◽  
Nearest Neighbor ◽  
Average Distance ◽  
Local Maximum ◽  
Fractal Dimensions ◽  
Dimension Formula ◽  
Phonon Spectra ◽  
Wide Range ◽  
Silver Mean

The microscopic harmonic model of lattice dynamics of the binary chains of atoms is formulated and studied numerically. The dependence of spring constants of the nearest-neighbor (NN) interactions on the average distance between atoms are taken into account. The covering fractal dimensions [Formula: see text] of the Cantor-set-like phonon spec-tra (PS) of generalized Fibonacci and non-Fibonaccian aperiodic chains containing of 16384≤N≤33461 atoms are determined numerically. The dependence of [Formula: see text] on the strength Q of NN interactions and on R=mH/mL, where mH and mL denotes the mass of heavy and light atoms, respectively, are calculated for a wide range of Q and R. In particular we found: (1) The fractal dimension [Formula: see text] of the PS for the so-called goldenmean, silver-mean, bronze-mean, dodecagonal and Severin chain shows a local maximum at increasing magnitude of Q and R>1; (2) At sufficiently large Q we observe power-like diminishing of [Formula: see text] i.e. [Formula: see text], where α=−0.14±0.02 and α=−0.10±0.02 for the above specified chains and so-called octagonal, copper-mean, nickel-mean, Thue-Morse, Rudin-Shapiro chain, respectively.

Energy Harvesting From the Vibrations of Rotating Systems

2017 ◽  
Vol 140 (2) ◽  
Author(s):  
Christopher G. Cooley ◽  
Tan Chai
Keyword(s):  
Rotation Speed ◽  
Excitation Frequency ◽  
Average Power ◽  
Local Maximum ◽  
Operating Conditions ◽  
Centripetal Acceleration ◽  
Local Maxima ◽  
Closed Form Solutions ◽  
Energy Harvesters ◽  
Wide Range

This study investigates the vibration of and power harvested by typical electromagnetic and piezoelectric vibration energy harvesters when applied to vibrating host systems that rotate at constant speed. The governing equations for these electromechanically coupled devices are derived using Newtonian mechanics and Kirchhoff's voltage law. The natural frequency for these devices is speed-dependent due to the centripetal acceleration from their constant rotation. Resonance diagrams are used to identify excitation frequencies and speeds where these energy harvesters have large amplitude vibration and power harvested. Closed-form solutions are derived for the steady-state response and power harvested. These devices have multifrequency dynamic response due to the combined vibration and rotation of the host system. Multiple resonances are possible. The average power harvested over one oscillation cycle is calculated for a wide range of operating conditions. Electromagnetic devices have a local maximum in average harvested power that occurs near a specific excitation frequency and rotation speed. Piezoelectric devices, depending on their mechanical damping, can have two local maxima of average power harvested. Although these maxima are sensitive to small changes in the excitation frequency, they are much less sensitive to small changes in rotation speed.

Critical Values in Anatomic Pathology

2006 ◽  
Vol 130 (5) ◽  
pp. 638-640 ◽  
Author(s):  
Jan F. Silverman ◽  
Telma C. Pereira
Keyword(s):  
Patient Safety ◽  
Improve Patient Safety ◽  
Clinical Pathology ◽  
Critical Values ◽  
Surgical Pathology ◽  
Anatomic Pathology ◽  
Wide Range ◽  
Enhance Patient Safety ◽  
Pathology Reports ◽  
Improve Patient

Abstract Similar to critical values (CVs) in clinical pathology, occasional diagnoses in surgical pathology and cytology could require immediate notification of the physician to rapidly initiate treatment. However, there are no established CV guidelines in anatomic pathology. A retrospective review of surgical pathology reports was recently conducted to study the incidence of CVs in surgical pathology and to survey the perceptions of pathologists and clinicians about CVs in surgical pathology, with a similar analysis of CVs performed in cytology. The results indicated that CVs in surgical pathology and cytology are uncommon but not rare and that there is a wide range of opinion among pathologists and between pathologists and clinicians about the need for an immediate telephone call and about the degree of urgency. It was obvious from the study that there is a lack of consensus in identifying what constitutes surgical pathology and cytology CV cases. Since the Institute of Medicine's report on medical errors, there has been an increasing number of initiatives to improve patient safety. Having guidelines for anatomic pathology CVs could enhance patient safety, in contrast to the current practice in which CV cases are managed based on common sense and on personal experience. Therefore, a discussion involving the pathology community might prove useful in an attempt to establish anatomic pathology CV guidelines that could represent a practice improvement.

scholarly journals Paediatric neurorehabilitation: finding and filling the gaps through the use of the Institute for Manufacturing strategic roadmapping method

2017 ◽  
Vol 3 (3) ◽  
pp. 137-143 ◽  
Author(s):  
Colin Hamilton ◽  
Anna Maw ◽  
Andrew Gill ◽  
Mita Brahmbhatt ◽  
Robert Phaal ◽  
...  
Keyword(s):  
Improve Patient Care ◽  
Healthcare Setting ◽  
Technology Evaluation ◽  
Rehabilitation Technology ◽  
Wide Range ◽  
Systematic Understanding ◽  
Specialist Rehabilitation ◽  
Level Of Understanding ◽  
Improve Patient ◽  
Current Experience

IntroductionAcquired brain injury (ABI) is a major cause of morbidity and mortality in childhood. Specialist rehabilitation services are often situated far from families and local services may be non-standardised and fragmented. A strategic level of understanding is needed to improve patient care and outcomes. Roadmapping techniques are commonly used in industry settings to discover and present a systematic understanding of structures; however, they are rarely used in the healthcare setting. With continuing pressures on healthcare systems worldwide, they provide an effective method for examining services.MethodsThe Institute for Manufacturing (IfM) strategic roadmapping method was used to identify areas of difficulty and opportunities in paediatric neurorehabilitation. Participants included stakeholders from a wide range of professions and sectors who have input with children after ABI.ResultsDelegates identified a range of ‘layers’ covering trends, drivers, current experience and unmet needs. From these layers, four priorities were identified and further expanded.These included: ‘access to medical and therapy expertise close(r) to home’, ‘shared understanding across family, school and health’, ‘family and professional awareness of resources and support’ and ‘establishing a centre for rehabilitation technology evaluation, advice and co-ordination of services and research’.ConclusionThe IfM strategic roadmapping method identified and developed key areas for development in the field of paediatric neurological rehabilitation. Healthcare professionals looking at strategic level difficulties should strongly consider the use of such systematic tools when evaluating areas of practice.

scholarly journals Deciphering Aspergillus fumigatus cyp51A-mediated triazole resistance by pyrosequencing of respiratory specimens

2020 ◽  
Vol 75 (12) ◽  
pp. 3501-3509
Author(s):  
Lilyann Novak-Frazer ◽  
Samuel P Anees-Hill ◽  
Darin Hassan ◽  
Rikesh Masania ◽  
Caroline B Moore ◽  
...  
Keyword(s):  
Aspergillus Fumigatus ◽  
Sanger Sequencing ◽  
Susceptibility Testing ◽  
High Volume ◽  
Resistant Genotype ◽  
Wide Range ◽  
Standard Culture ◽  
The Uk ◽  
Improve Patient ◽  
Respiratory Specimens

Abstract Background Infections caused by triazole drug-resistant Aspergillus fumigatus are an increasing problem. The sensitivity of standard culture is poor, abrogating susceptibility testing. Early detection of resistance can improve patient outcomes, yet tools for this purpose are limited. Objectives To develop and validate a pyrosequencing technique to detect resistance-conferring cyp51A polymorphisms from clinical respiratory specimens and A. fumigatus isolates. Methods Method validation was performed by Sanger sequencing and pyrosequencing of 50 A. fumigatus isolates with a spectrum of triazole susceptibility patterns. Then, 326 Aspergillus quantitative PCR (qPCR)-positive respiratory samples collected over a 27 month period (January 2017–March 2019) from 160 patients at the UK National Aspergillosis Centre were assessed by cyp51A pyrosequencing. The Sanger sequencing and pyrosequencing results were compared with those from high-volume culture and standard susceptibility testing. Results The cyp51A genotypes of the 50 isolates analysed by pyrosequencing and Sanger sequencing matched. Of the 326 Aspergillus qPCR-positive respiratory specimens, 71.2% were reported with no A. fumigatus growth. Of these, 56.9% (132/232) demonstrated a WT cyp51A genotype and 31.5% (73/232) a resistant genotype by pyrosequencing. Pyrosequencing identified the environmental TR34/L98H mutation in 18.7% (61/326) of the samples in contrast to 6.4% (21/326) pan-azole resistance detected by culture. Importantly, pyrosequencing detected resistance earlier than culture in 23.3% of specimens. Conclusions The pyrosequencing assay described could detect a wide range of cyp51A polymorphisms associated with triazole resistance, including those not identified by commercial assays. This method allowed prompt recognition of resistance and the selection of appropriate antifungal treatment when culture was negative.

Design of a Reconfigurable Dynamic Testbed for Co-Design Method Validation

2017 ◽  
Author(s):  
Anand P. Deshmukh ◽  
Danny J. Lohan ◽  
James T. Allison
Keyword(s):  
Control System ◽  
Design Method ◽  
Design Methods ◽  
System Architectures ◽  
Car Suspension ◽  
Kinematic Behavior ◽  
Wide Range ◽  
Physical Testing ◽  
Dynamic Testbed ◽  
And Control

Physical testing as a technique for validation of engineering design methods can be a valuable source of insights not available through simulation alone. Physical testing also helps to ensure that design methods are suitable for design problems with a practical level of detail, and can reveal issues related to interactions not captured by physics-based computer models. Construction of physical and testing of physical prototypes, however, is costly and time consuming so it is not often used when investigating new design methods for complex systems. This gap is addressed through an innovative testbed presented here that can be reconfigured to achieve a range of different prototype design properties, including kinematic behavior and different control system architectures. Thus, a single testbed can be used for validation of numerous design geometries and control system architectures. The testbed presented here is a mechanically and electronically reconfigurable quarter-car suspension testbed with nonlinear elements that is capable of testing a wide range of both optimal and sub-optimal design prototypes using a single piece of equipment. Kinematic suspension properties can be changed in an automated way to reflect different suspension linkage designs, spring and damper properties can be adjusted in real time, and control system design can be changed easily through streamlined software modifications. While the specific case study is focused on development of a reconfigurable system for validation of co-design methods, the concept extends to physical validation using reconfigurable systems for other classes of design methods.

scholarly journals Stroke Biomarkers: Progress and Challenges for Diagnosis, Prognosis, Differentiation, and Treatment

2010 ◽  
Vol 56 (1) ◽  
pp. 21-33 ◽  
Author(s):  
Amy K Saenger ◽  
Robert H Christenson
Keyword(s):  
Point Of Care ◽  
Clinical Settings ◽  
Acute Setting ◽  
Wide Range ◽  
Novel Biomarkers ◽  
Further Development ◽  
Improve Patient ◽  
Single Set ◽  
Neuroimaging Techniques

Abstract Background: Stroke is a devastating condition encompassing a wide range of pathophysiological entities that include thrombosis, hemorrhage, and embolism. Current diagnosis of stroke relies on physician clinical examination and is further supplemented with various neuroimaging techniques. A single set or multiple sets of blood biomarkers that could be used in an acute setting to diagnosis stroke, differentiate between stroke types, or even predict an initial/reoccurring stroke would be extremely valuable. Content: We discuss the current classification, diagnosis, and treatment of stroke, focusing on use of novel biomarkers (either solitary markers or multiple markers within a panel) that have been studied in a variety of clinical settings. Summary: The current diagnosis of stroke remains hampered and delayed due to lack of a suitable mechanism for rapid (ideally point-of-care), accurate, and analytically sensitive biomarker-based testing. There is a clear need for further development and translational research in this area. Potential biomarkers identified need to be transitioned quickly into clinical validation testing for further evaluation in an acute stroke setting; to do so would impact and improve patient outcomes and quality of life.

scholarly journals Hybrids Molecularly Imprinted Polymers: The Future of Nanomedicine?

2021 ◽  
Author(s):  
Maylis Garnier ◽  
Michele Sabbah ◽  
Christine Ménager ◽  
Nébéwia Griffete
Keyword(s):  
Molecularly Imprinted Polymers ◽  
Improve Patient Care ◽  
Molecularly Imprinted ◽  
Imprinted Polymers ◽  
Wide Range ◽  
Lack Of Control ◽  
Inorganic Nanomaterials ◽  
Complex Detection ◽  
Improve Patient

Molecularly imprinted polymers (MIPs) have been widely used in nanomedicine during the last few years. However, their potential is limited by their intrinsic properties resulting, for instance, in lack of control in drug release processes or complex detection for in vivo imaging. Recent attempts in creating hybrid nanomaterials combining MIPs with inorganic nanomaterials succeeded in providing a wide range of new interesting properties suitable for nanomedicine. Through this review, we aim to illustrate how hybrids molecularly imprinted polymers may improve patient care with enhanced imaging, treatments and combination of both.

Correlation of 13C NMR Analysis and Physical Testing Results of Natural Rubber

2003 ◽  
Vol 76 (1) ◽  
pp. 212-219 ◽  
Author(s):  
Dallas D. Parker ◽  
J. L. Koenig ◽  
Makio Mori
Keyword(s):  
Natural Rubber ◽  
13C Nmr ◽  
Nmr Analysis ◽  
Testing Methods ◽  
13C Nmr Analysis ◽  
Wide Range ◽  
Physical Testing ◽  
Cure Time ◽  
Small Change ◽  
Cure Temperature

Abstract The methods of solid-state 13C NMR and physical testing were used to examine carbon black filled natural rubber samples. The rubber samples were vulcanized under varying parameters of sulfur loading, cure times, and cure temperature. At constant cure time and cure temperature, the two testing methods correlate well over a wide range of sulfur concentrations. Varying cure time and cure temperature produced large changes in the mechanical testing results but small change in the 13C NMR analysis of the sulfur vulcanizates.

Sign in / Sign up

Export Citation Format

Share Document