6,678 research outputs found
RF communication with implantable wireless device: effects of beating heart on performance of miniature antenna
The frequency response of an implantable antenna is key to the performance of a wireless implantable sensor. If the antenna detunes significantly, there are substantial power losses resulting in loss of accuracy. One reason for detuning is because of a change in the surrounding environment of an antenna. The pulsating anatomy of the human heart constitutes such a changing environment, so detuning is expected but this has not been quantified dynamically before. Four miniature implantable antennas are presented (two different geometries) along with which are placed within the heart of living swine the dynamic reflection coefficients. These antennas are designed to operate in the short range devices frequency band (863-870 MHz) and are compatible with a deeply implanted cardiovascular pressure sensor. The measurements recorded over 27 seconds capture the effects of the beating heart on the frequency tuning of the implantable antennas. When looked at in the time domain, these effects are clearly physiological and a combination of numerical study and posthumous autopsy proves this to be the case, while retrospective simulation confirms this hypothesis. The impact of pulsating anatomy on antenna design and the need for wideband implantable antennas is highlighted
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A whole-health-economy approach to antimicrobial stewardship: Analysis of current models and future direction.
Antimicrobial stewardship (AMS) strategies are widely implemented in single healthcare sectors and organisations; however, the extent and impact of integrated AMS initiatives across the whole health economy are unknown.
Assessing degree of integration of AMS across the whole health economy and its impact is essential if we are to achieve a ‘One Health’ approach to addressing antimicrobial resistance (AMR), and therefore we searched systematically for and analysed published examples of integrated AMS initiatives to address this gap.
Application of a system-level framework to analyse integration of AMS initiatives across and within healthcare sectors shows that integration is emerging but needs strengthening.
Findings from a small number of evaluations in high-income countries suggest that antimicrobial prescribing and healthcare-associated infections can be reduced using a multisectoral integrated AMS approach.
More robust research designs to evaluate and understand the impact of multisectoral integrated AMS are needed, particularly with respect to differing health systems in different countries and local organisational contexts.
Our analysis highlights a number of challenges and ways forward for enhancing the delivery of AMS through an integrated approach
A Systematic Review of Osteoporosis Health Beliefs in Adult Men and Women
Osteoporosis is major public health concern affecting millions of older adults worldwide. A systematic review was carried out to identify the most common osteoporosis health beliefs in adult men and women from descriptive and intervention studies. The Osteoporosis Health Belief Scale (OHBS) and Osteoporosis Self-efficacy Scale (OSES) evaluate osteoporosis health beliefs, including perceived susceptibility and seriousness, benefits, barriers, and self-efficacy of calcium and exercise, and health motivation, and their relationship to preventive health behaviours. A comprehensive search of studies that included OHBS and OSES subscale scores as outcomes was performed. Fifty full-text articles for citations were reviewed based on inclusion criteria. Twenty-two articles met the inclusion criteria. Greater perceived seriousness, benefits, self-efficacy, health motivation, and fewer barriers were the most common health-belief subscales in men and women. Few studies were interventions (n = 6) and addressed osteoporosis health beliefs in men (n = 8). Taking health beliefs into consideration when planning and conducting education interventions may be useful in both research and practice for osteoporosis prevention and management; however, more research in this area is needed
Transcutaneous measurement of volume blood flow
Blood flow velocity measurements, using Doppler velocimeter, are described. The ability to measure blood velocity using ultrasound is derived from the Doppler effect; the change in frequency which occurs when sound is reflected or transmitted from a moving target. When ultrasound of the appropriate frequency is transmitted through a moving blood stream, the blood cells act as point scatterers of ultrasonic energy. If this scattered ultrasonic energy is detected, it is found to be shifted in frequency according to the velocity of the blood cells, nu, the frequency of the incident sound, f sub o, the speed of sound in the medium, c, and the angle between the sound beam and the velocity vector, o. The relation describing this effect is known as the Doppler equation. Delta f = 2 f sub o x nu x cos alpha/c. The theoretical and experimental methods are evaluated
Multiple Sample Cryostat for the Determination of Superconductor Properties
Cryostats which are currently used to characterize the properties of superconductors between 4 K and 100 K are primarily single sample devices. The purpose of this paper is to present an instrument design which can hold up to five (5) one cm. diameter samples at a stable temperature (+ /-0.1K) within the above range specified while measurements of the sample properties are made
Development of ultrasonic methods for hemodynamic measurements
A transcutanous method to measure instantaneous mean blood flow in peripheral arteries of the human body was defined. Transcutanous and implanted cuff ultrasound velocity measurements were evaluated, and the accuracies of velocity, flow, and diameter measurements were assessed for steady flow. Performance criteria were established for the pulsed Doppler velocity meter (PUDVM), and performance tests were conducted. Several improvements are suggested
A retrospective analysis of responsible innovation for low-technology innovation in the Global South
This is the final version. Available from the publisher via the DOI in this record.The role of low-technology innovation in addressing global challenges is undervalued. Responsible innovation (RI) has the potential to direct low-technology innovation toward global challenges in the Global South, yet this possibility remains largely unexplored. Through a retrospective analysis, this article explores how researchers grapple with dimensions of an RI framework in a research project and highlights key areas for researchers to consider when involved with low-technology innovation in a development context. The analysis demonstrates that RI can structure discussion and create space for anticipation, reflection and engagement with stakeholders. However, even when researchers are committed to the idea of RI, it is difficult to enact in practice. Although RI places significant emphasis on inclusive and meaningful engagement as imagined by co-development and inclusive models of innovation, the deficit model of public engagement presents a formidable barrier. Surprisingly, low-technology innovators are likely to face the same struggles as high technology innovators with regards to engagement that allows end-users to shape the technology which may ultimately benefit them.Leverhulme TrustEngineering and Physical Science Research Council (EPSRC)Biotechnology and Biological Sciences Research Council (BBSRC
A Systematic Review of the Efficacy of Motivational Interviewing on Occupational Performance
This systematic review aims to review the efficacy of MI to address such performance goals falling within the occupational therapy scope of practice
Effects of intra-operative language mapping and speech and language therapy (salt) on awake craniotomy tumour resection: A case series
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