Tinnitus and Hyperacusis
John C Watkinson, Raymond W Clarke, Christopher P Aldren, Doris-Eva Bamiou, Raymond W Clarke, Richard M Irving, Haytham Kubba, Shakeel R Saeed in Paediatrics, The Ear, Skull Base, 2018
Conversely, tinnitus can exist even if the auditory periphery has been completely destroyed or after the neural connections between ear and brain have been severed, as can be seen following some forms of vestibular schwannoma surgery.36 In addition, damage to the auditory system does not automatically induce tinnitus: although noise-induced hearing loss increases the likelihood of someone reporting tinnitus, the majority of people with cochlear damage secondary to noise exposure do not have significant tinnitus. These observations have been drawn together in a concept that makes a distinction between the location, within either the peripheral or central auditory system, at which an initial tinnitus signal is generated and the subsequent central auditory mechanism by which this signal is misconstrued as a sound with the potential to become a clinical problem. The point at which the initial signal generation occurs has been dubbed the ignition site and the ensuing central mechanisms have been entitled promotion.37 Pathological events which create an ignition site do not inevitably generate tinnitus – the central promotion must also be present. This theory has clinical relevance in that, if tinnitus distress is maintained by central auditory pathways, it may be futile trying to correct peripheral auditory pathology.
Combined models of artificial immune systems
Waldemar Wójcik, Andrzej Smolarz in Information Technology in Medical Diagnostics, 2017
Combustion of pulverised coal was examined through optical methods, which were based on analysis of wide spectrum radiation emitted by the flame. The analysis also takes into account spatial features of such radiation source. Combustion of pulverised coal in the power burner takes place in a turbulent flow. At each point of it local fluctuations of both fuel and gaseous reagent concentrations, as well as temperature, occur. This leads to permanent local changes in the combustion process intensity, which results in continuous changes in flame luminosity that can be observed as flame flicker. As the combustion process affects the turbulent movement of its products and reagents, it determines the way the flame flicker parameters such as mean luminosity and luminosity frequency spectrum. A number of combustion supervision and flame-fault protection systems use information contained within flame flicker. The multichannel fibre-optic flame monitoring system developed at the Lublin University of Technology belongs to this class of solutions, additionally allowing observation of selected areas of the flame (Wójcik et al. 2001).
Station 2: History Taking
Saira Ghafur, Parminder K Judge, Richard Kitchen, Samuel Blows, Fiona Moss in The MRCP PACES Handbook, 2017
Neurological:Resting tremor (4–6 Hz), rigidity (can be cog-wheeling in presence of rest tremor), bradykinesia (progressive decrement of amplitude of repetitive movements such as finger tapping).Gait: Ignition failure, short stride length, festination, freezing.Soft and monotonous speech.Micrographia.Rigidity can be demonstrated with concurrent activity (synkinesis – waving the right arm when assessing for the left). Distraction can bring out rest tremor – arm tremor is sometimes only revealed when testing gait or asking the patient to do a cognitive task like serial seven subtraction.
Complications associated with PEAK PlasmaBlade from 2010 to 2020 from MAUDE
Published in Baylor University Medical Center Proceedings, 2022
Esther Lee, Amir Elzomor, Sameh Boulos, Olivia Silva, Luke J. Pasick, Daniel A. Benito, Jane Tong, Philip Zapanta, Arjun S. Joshi, Joseph F. Goodman, Punam G. Thakkar
The second most reported cause of device malfunction was ignition or fire (56, 13.2%). This is particularly concerning given that intraoperative fires occur most commonly in otolaryngology surgical procedures and can lead to serious adverse events that could potentially jeopardize patient safety and procedural outcomes.11 PlasmaBlade-related ignition or fire can also occur as a result of operator misuse. Improper suctioning can lead to increased amounts of oxidized and/or flammable substances, leading to an increased risk of ignition or fire.8 Yamasaki et al found intraoperative ignition or fire to be the most commonly reported electrosurgical device malfunction.12 They found that 28% of ignition or fire was associated with coblation devices, 3% with monopolar devices, and 1% with electrosurgical generators.
Numerical investigation of the effect of air supply on cook stove performance
Published in Inhalation Toxicology, 2021
Ankur Kaundal, Satvasheel Powar, Atul Dhar
Wood combustion is a complicated process of burning; combustion is the result of reactions between oxygen and gasses emitted from the feedstock, not solid feedstock. Upon heating solid feedstock releases gaseous components viz—pyrolysis gases with high oxygen affinity to react and create flames. Temperature due to this exothermic reaction is very high, making combustion luminous and flaming. Primary air and heating of the wood are responsible for releasing the volatiles. In short, it's called primary wood combustion. The remaining air supplied throughout the process is secondary air. Number of vents are placed on the horizontal sections of pipes (shown in Figure 1) inside the combustion chamber for the induction of secondary air. Oxygen in secondary air reacts with volatiles, resulting in flaming combustion. An appropriate mechanism for primary and secondary air intake is therefore essential for efficient cook stove operation.
In-situ tensile test under microtomography to characterize mechanical behavior of ethmoid bone: a preliminary study
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2020
V. Serantoni, N. Faraj, G. Subsol, E. Rondet, L. Ollier, G. Captier, F. Jourdan, V. Favier
The largest dimensions of the bone samples were 8 × 7 × 1 mm. Complete load evolution during the tensile test is shown in Figure 2. Each micro-CT scan lasted 2h30; therefore, the total experiment lasted 8 to 10 hours. As a consequence, a creep phenomenon seems to appear during CT scanning, causing relaxation which is visible in the curve. The tensile test was stopped at 80 N and, because the bone was not fractured yet, the tensile test was extended above 80 N several hours after the last scan, leading to some relaxation at 80 N higher than previous steps. The bone section area, where fracture occurs, was close to 5 mm2 and the load during fracture was about 85 N. Using Equation 1, the ultimate stress at failure was estimated close to 17 MPa. Fracture ignition (micro cracks) was observed for a strain of 0.96% and a complete fracture was observed after a strain of 1.25% (Figure 2). It was possible to estimate the extension of the bone between the load-free CT scan and the 80 N CT scan by tracking some geometrical landmarks, easy to locate. The extension of the bone was evaluated at 38.5 μm, and the initial distance between the clamp was approximately 5 mm, leading to an estimation of E at 2.08 Gpa (Eq. 2).
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- Chemical Reaction
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- Smoke
- Redox
- Activation Energy
- Elementary Reaction
- Radical
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