1,330 research outputs found
The integration of on-line monitoring and reconfiguration functions using IEEE1149.4 into a safety critical automotive electronic control unit.
This paper presents an innovative application of IEEE 1149.4 and the integrated diagnostic reconfiguration (IDR) as tools for the implementation of an embedded test solution for an automotive electronic control unit, implemented as a fully integrated mixed signal system. The paper describes how the test architecture can be used for fault avoidance with results from a hardware prototype presented. The paper concludes that fault avoidance can be integrated into mixed signal electronic systems to handle key failure modes
A significant statement: new outlooks on treatment documentation
Values-based conservation is an increasingly dominant theme in heritage conservation theory. It is less routine in the application of object conservation practice, where emphasis on the physical fabric of heritage prevails. Materials-based approaches pivot conservation decisions on assessments of object condition. Values-based approaches posit that conservation should seek to sustain and enhance heritage significance rather than arrest physical change. A values-based approach is also one where the value-judgements underlying conservation decisions are made explicit. To reflect this, a new treatment documentation format has been developed at the UCL Institute of Archaeology. The documentation procedure shifts the focal point from condition assessments to statements of significance. Within the professional setting, similar new documentation is being developed for light-based artworks at Glasgow Museums. Ultimately, using a value-based treatment report, the conservator can be aware of the reasoning behind treatment choices and be better equipped to make decisions that reflect an objectâs values
Aortic stenting for neonatal coarctation of the aorta : when should this be considered?
Aortic coarctation (CoA) constitutes the fifth most common congenital heart defect (1 in 2500 live births). This lesion comprises 5-8% of congenital heart disease and has variable severity and mode of presentation. Critical coarctation in newborns usually presents with severe narrowing of the upper thoracic aorta below the isthmus and adjacent to the arterial duct, and is dependent on duct patency for survival. Rapid deterioration of the patient usually results from spontaneous closure of the patent arterial duct (PDA). This deterioration is in part due to reduced renal perfusion resulting in fluid and acid retention causing heart failure and metabolic acidosis. This may be alleviated by the administration of intravenous prostaglandin, with temporary improvement of distal aortic blood flow, and overall condition. The treatment of choice is surgical resection with the âextended end-to-endâ technique.
We present a case of a severely ill newborn with complex coarctation, multiorgan failure, disseminated intravascular coagulation and oedema, who was treated with emergency stenting on the tenth day of life. This was followed by surgical stent removal and repair of the arch on the 29th day of life. We followed the strategy of minimally invasive interventional bridging of a borderline patient with regard to the experience of stenting of native coarctations in older patients, or complex recurrent stenosis of previously surgically treated childrenpeer-reviewe
BrachyView, a novel in-body imaging system for HDR prostate brachytherapy: Experimental evaluation
Š 2015 American Association of Physicists in Medicine. Purpose: This paper presents initial experimental results from a prototype of high dose rate (HDR) BrachyView, a novel in-body source tracking system for HDR brachytherapy based on a multipinhole tungsten collimator and a high resolution pixellated silicon detector array. The probe and its associated position estimation algorithms are validated and a comprehensive evaluation of the accuracy of its position estimation capabilities is presented. Methods: The HDR brachytherapy source is moved through a sequence of positions in a prostate phantom, for various displacements in x, y, and z. For each position, multiple image acquisitions are performed, and source positions are reconstructed. Error estimates in each dimension are calculated at each source position and combined to calculate overall positioning errors. Gafchromic film is used to validate the accuracy of source placement within the phantom. Results: More than 90% of evaluated source positions were estimated with an error of less than one millimeter, with the worst-case error being 1.3 mm. Experimental results were in close agreement with previously published Monte Carlo simulation results. Conclusions: The prototype of HDR BrachyView demonstrates a satisfactory level of accuracy in its source position estimation, and additional improvements are achievable with further refinement of HDR BrachyView's image processing algorithms
BrachyView, A novel inbody imaging system for HDR prostate brachytherapy: Design and Monte Carlo feasibility study
Purpose: High dose rate (HDR) brachytherapy is a form of radiation therapy for treating prostate cancer whereby a high activity radiation source is moved between predefined positions inside applicators inserted within the treatment volume. Accurate positioning of the source is essential in delivering the desired dose to the target area while avoiding radiation injury to the surrounding tissue. In this paper, HDR BrachyView, a novel inbody dosimetric imaging system for real time monitoring and verification of the radioactive seed position in HDR prostate brachytherapy treatment is introduced. The current prototype consists of a 15 à 60 mm2 silicon pixel detector with a multipinhole tungsten collimator placed 6.5 mm above the detector. Seven identical pinholes allow full imaging coverage of the entire treatment volume. The combined pinhole and pixel sensor arrangement is geometrically designed to be able to resolve the three-dimensional location of the source. The probe may be rotated to keep the whole prostate within the transverse plane. The purpose of this paper is to demonstrate the efficacy of the design through computer simulation, and to estimate the accuracy in resolving the source position (in detector plane and in 3D space) as part of the feasibility study for the BrachyView project. Methods: Monte Carlo simulations were performed using the GEANT4 radiation transport model, with a 192Ir source placed in different locations within a prostate phantom. A geometrically accurate model of the detector and collimator were constructed. Simulations were conducted with a single pinhole to evaluate the pinhole design and the signal to background ratio obtained. Second, a pair of adjacent pinholes were simulated to evaluate the error in calculated source location. Results: Simulation results show that accurate determination of the true source position is easily obtainable within the typical one second source dwell time. The maximum error in the estimated projection position was found to be 0.95 mm in the imaging (detector) plane, resulting in a maximum source positioning estimation error of 1.48 mm. Conclusions: HDR BrachyView is a feasible design for real-time source tracking in HDR prostate brachytherapy. It is capable of resolving the source position within a subsecond dwell time. In combination with anatomical information obtained from transrectal ultrasound imaging, HDR BrachyView adds a significant quality assurance capability to HDR brachytherapy treatment systems. Š 2013 American Association of Physicists in Medicine
Malta : language, literacy and identity in a Mediterranean island society
Available documentation for the early modern period indicates that the Malta harbor towns achieved literacy earlier than the countryside. The Maltese townsmen lived on a trading route, and it was necessary for them to learn the lingua franca, as the language of
trade in the Mediterranean. The educated elite were able to acquire fluent speaking knowledge, as well as the ability to write, Tuscan (a dialect then in the process of becoming standard Italian), while continuing to employ their local Maltese âdialectâ on numerous occasions. By and large, the erosion of the position of Maltese as the subordinate language was an inevitable by-product of this development. The Maltese language was able to attain the function of a literary language in the nineteenth century but it had no standard orthography until 1931 and was only adopted as Maltaâs official language in 1964.peer-reviewe
Operational Application of an Adaptive Beamforming Approach for Angular Track Estimation in Survey Radars
Apparent absence of the amphibian chytrid fungus (Batrachochytrium dendrobatidis) in frogs in Malaita Province, Solomon Islands
A major driver of global biodiversity loss is disease. One of the most devastating wildlife diseases known is chytridiomycosis, which is caused by the amphibian chytrid fungus Batrachochytrium dendrobatidis, and is implicated in population declines in over 500 frog species. Thought to originate in Asia, B. dendrobatidis now has a global distribution, likely due to human movement and trade. The pathogen has yet to be detected in Melanesia, but there have been few surveys for B. dendrobatidis in the region, and none in the Solomon Islands archipelago, a biogeographic region with a unique and culturally important frog fauna. We swabbed 200 frogs of eight species in three genera in lowland and highland sites in East Kwaio on the island of Malaita in the Solomon Islands. All frogs tested negative for the pathogen but it is possible that the pathogen is present despite non-detection, so further surveys for the pathogen are needed throughout the country. Despite this, it is safest to take a precautionary approach and assume that B. dendrobatidis has not yet been introduced to the Solomon Islands, and that naĂŻve native amphibian populations may be at risk of decline if the pathogen is introduced. Protocols are needed to prevent the accidental import of infected frogs via tourism or in logging or mining equipment. Monitoring of frog populations near areas of high risk such as ports is also recommended. The frogs of the Solomon Islands archipelago are biologically unique and culturally significant, and protecting them from the potentially devastating impacts of B. dendrobatidis is vital
A time and motion study of patients presenting at the accident and emergency department at Mater Dei Hospital
<p>Abstract</p> <p>Background</p> <p>To carry out a time and motion study of patients presenting at the Emergency Department (ED) by measuring waiting times at the ED dept throughout the day. The objectives were:</p> <p indent="1">⢠to determine whether waiting times are prolonged, and</p> <p indent="1">⢠if prolonged, at which station(s) bottlenecks occur most often in terms of duration and frequency.</p> <p>Results will be compared to the United Kingdom guidelines of stay at the emergency department.</p> <p>Methods</p> <p>A group of 11 medical students monitored all patients who attended ED between 0600 hours on the 25<sup>th </sup>August and 0600 hours on the 1st September 2008. For each 24 hour period, students were assigned to the triage room and the 3 priority areas where they monitored all patient-related activity, movement and waiting times so that length of stay (LOS) could be recorded. The key data recorded included patient characteristics, waiting times at various ED process stages, tests performed, specialist consultations and follow up until admitted, discharged, or referred to another hospital area. Average waiting times were calculated for each priority area. Bottle-necks and major limiting factors were identified. Results were compared against the United Kingdom benchmarks - i.e. 1 hour until first assessment, and 4 hours before admitting/discharge.</p> <p>Results</p> <p>1779 patients presented to the ED in the week monitored. As expected, patients in the lesser priority areas (i.e. 2 & 3) waited longer before being assessed by staff. Patients requiring laboratory and imaging investigations had a prolonged length of stay, which varied depending on specific tests ordered. Specialty consultation was associated with longer waiting times. A major bottleneck identified was waiting times for inpatient admission.</p> <p>Conclusions</p> <p>In conclusion, it was found that 30.3% of priority 1 patients, 86.3% of priority 2 patients and 76.8% of priority 3 patients waited more than 1 hour for first assessment. We conclude by proposing several changes that may expedite throughput.</p
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