61 research outputs found
Cellular Automaton Study of Time-Dynamics of Avalanche Breakdown in IMPATT Diodes
Employing a recently developed efficient cellular automaton technique for solving
Boltzmann's transport equation for realistic devices, we present a detailed study of the
carrier dynamics in GaAs avalanche p-i-n (IMPATT) diodes. We find that the impact
ionization in reverse bias p-i-n diodes with ultrathin (less than 50 nm) intrinsic regions is
triggered by Zener tunneling rather than by thermal generation. The impact generation
of hot carriers occurs mainly in the low-field junction regions rather than in the high
field intrinsic zone. The calculations predict significantly more minority carriers on the
n-side than on the p-side
Disposable chlorine dioxide wipes for high-level disinfection in the ENT department: A systematic review
Background: Nasopharyngoscope reprocessing methods should be effective, rapid and reproducible with moderate cost. Tristel Trio Wipes system (TTWS) is a manual reprocessing method based on chlorine dioxide that has lately emerged in ENT department. This review aims to collect evidence on this system. Methods: The PubMed, Web of Science and Cochrane Library databases were searched for all the studies on TTWS or one of its components. Data were grouped according to the study type. Results: Ten articles were included in the review. TTWS ensured high-level disinfection in laboratory and clinical setting. Although the limitations of the manual systems, TTWS proved to be faster than automated endoscope reprocessing (AER) and safe for patients and health-care workers. TTWS represented cheaper system than AER or sheaths in low- and medium-volume centers. Conclusion: TTWS could be a valid, safe and fast HLD method for nasopharyngoscopes, with reasonable costs for medium-low reprocessing volumes
14th International Conference on Nonequilibrium Carrier Dynamics in Semiconductors
International experts gather every two years at this established conference to discuss recent developments in theory and experiment in non-equilibrium transport phenomena. These developments have been the driving force behind the spectacular advances in semiconductor physics and devices over the last few decades. Originally known as "Hot Carriers in Semiconductors," the 14th conference in the series covered a wide spectrum of traditional topics dealing with non-equilibrium phenomena, ranging from quantum transport to optical phenomena in mesoscopic and nano-scale structures. Particular attention was given this time to emerging areas of this rapidly evolving field, with many sessions covering terahertz devices, high field transport in nitride semiconductors, spintronics, molecular electronics, and bioelectronics applications
Laryngeal manifestations of Crohn’s disease
Crohn’s disease is a chronic inflammatory bowel disease. It should be considered a multisystemic disease due to its extra-intestinal manifestations found in 25-40% of patients with inflammatory bowel disease. Laryngeal involvement is very uncommon and the lesions in hypopharynx and larynx are edema, ulcerations and granulation tissue. Symptoms are dysphonia, dysphagia, odynophagia and airway restriction. Laryngeal manifestations of Crohn’s disease are usually successfully treated with oral steroids. We describe a 54-year-old woman who presented with dysphagia and odynophagia for 20 days. She had a history of Crohn’s disease for 6 years. Laryngoscopy revealed a cobblestone appearance of epiglottis and laryngeal vestibule. A biopsy of the lesion of the epiglottis was taken and histologic analysis revealed a nonspecific chronic inflammation suggestive of Crohn’s disease. Therefore the patient was treated with oral steroids and laryngeal lesions resolved in a week. To date, the correlation between intestinal symptoms and head and neck manifestations is unknown. Though our case report suggests that head and neck manifestations are not related to bowel inflammatory activity. However more studies are required to deepen this matter
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