Implementation of the University of Missouri Terawatt Test Stand and the study of a large, multichanneling, laser tirggered gas switch

The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file.Title from title screen of research.pdf file viewed on (February 27, 2007)Vita.Thesis (Ph.D.) University of Missouri-Columbia 2006.The University of Missouri Terawatt Test Stand is one of the world's largest university operated pulsed power facilities. It was developed and implemented, for a fraction of similar facilities cost, under the supervision of the author. The test stand was routinely operated at up to 200 kA at approximately 200 ns FWHM and 600 kV into appropriate loads. The test stand provides a valuable resource for pulsed power experimentation in areas ranging from component evaluation to wire array physics. The laboratories original initiative was to research 2.5 MV laser triggered gas switches. Experiments were conducted in voltage ranges from 800 kV to 2.5 MV, with peak currents of over 175 kA, using air and SF6 as fill gases. These parameters, along with electrode type, configuration, and size were varied to experimentally understand multichanneling and low inductance configurations for large laser triggered gas switches. This effort discovered that for very low impedance gas switching, avenues of drastic redesign of existing switches must be explored as opposed to modest design changes to meet stringent impedance requirements for future inertial confinement fusion programs. From this initiative, novel results were obtained that may be utilized for the future design of large, low inductance gas switches.Includes bibliographical reference

Taking the pulse of the real economy using financial statement analysis: the european perspective

This article shows that an analysis of aggregated changes in profitability and profitability drivers is useful to forecast European economic growth. Furthermore the predictive power contained in profitability ratios is incremental and thus complementary to that contained in stock returns. Although European professional forecasters tend to incorporate equity returns and accounting information in their revisions of output growth expectations, their prediction errors can be anticipated based on aggregate changes in Return on Equity, Net Profit Margin and on stock returns. It implies that macro experts do not fully rely on easily available information to forecast E.U real GDP growth

Evolving test instances of the Hamiltonian completion problem

Predicting and comparing algorithm performance on graph instances is challenging for multiple reasons. First, there is usually no standard set of instances to benchmark performance. Second, using existing graph generators results in a restricted spectrum of difficulty and the resulting graphs are usually not diverse enough to draw sound conclusions. That is why recent work proposes a new methodology to generate a diverse set of instances by using an evolutionary algorithm. We can then analyze the resulting graphs and get key insights into which attributes are most related to algorithm performance. We can also fill observed gaps in the instance space in order to generate graphs with previously unseen combinations of features. This methodology is applied to the instance space of the Hamiltonian completion problem using two different solvers, namely the Concorde TSP Solver and a multi-start local search algorithm.Comment: 12 pages, 12 figures, minor revisions in section

Pediatric Laryngopharyngeal Reflux: An Evidence-Based Review.

peer reviewed[en] PURPOSE: Pediatric laryngopharyngeal reflux (P-LPR) is associated with the development of common otolaryngological symptoms and findings. In the present study, the findings about epidemiology, clinical presentation, diagnostic and therapeutic outcomes of pediatric population were reviewed. METHODS: A PubMed, Cochrane Library, and Scopus literature search was conducted about evidence-based findings in epidemiology, clinical presentation, diagnostic and therapeutic outcomes of P-LPR. FINDINGS: The prevalence of LPR remains unknown in infant and child populations. The clinical presentation depends on age. Infants with LPR symptoms commonly have both gastroesophageal reflux disease (GERD) and laryngopharyngeal reflux and related digestive, respiratory and ear, nose and throat symptoms. The GERD prevalence appears to decrease over the growth, and the clinical picture is increasingly associated with LPR symptoms and findings without GERD. The prevalence of LPR and proximal acid and nonacid esophageal reflux events may be high in some prevalent otolaryngological conditions (chronic otitis media, laryngolomalacia and apnea). However, the lack of use of hypopharyngeal-esophageal multichannel intraluminal impedance pH monitoring (HEMII-pH) limits the establishment of etiological associations. Proton pump inhibitors are less effective in P-LPR patients compared to GERD populations, which may be related to the high prevalence of weakly or nonacid reflux events. CONCLUSIONS: Many gray areas persist in P-LPR and should be not resolved without the establishment of diagnostic criteria (guidelines) based on HEMII-pH. The unavailability of HEMII-pH and the poor acid-suppressive therapeutic response are all issues requiring future investigations. Future controlled studies using HEMII-pH and enzyme measurements in ear, nose or throat fluids may clarify the epidemiology of P-LPR according to age and its association with many otolaryngological conditions

Minimum Effective Duration of Laryngopharyngeal Reflux Disease Treatment: A Prospective Study.

peer reviewed[en] OBJECTIVE: To investigate the minimum therapeutic duration for patients with primary laryngopharyngeal reflux disease (LPRD) through the evaluation of symptom changes at multiple time points. STUDY DESIGN: Prospective uncontrolled. SETTING: University medical center. METHODS: Patients with LPRD at the 24-hour hypopharyngeal-esophageal multichannel intraluminal impedance-pH monitoring were recruited from the European Reflux Clinic. Depending on the type of LPRD, patients were treated with a combination of proton-pump inhibitors, alginate, or magaldrate. Symptoms were evaluated with the reflux symptom score (RSS) at baseline and throughout treatment (1-, 3-, 6-, and 9-month posttreatment). The most appropriate therapeutic duration was determined using the RSS changes. Signs were evaluated with the reflux sign assessment. RESULTS: A total of 159 patients completed the study. The mean age was 49.9 ± 15.7 years. At 1-month posttreatment, 97 patients (61.0%) were considered as early responders to treatment, and the treatment was stopped for 52 patients (32.7%). Of the 62 early nonresponders, 34 patients (21.4%) reached responded to treatment after 3 to 9 months. The cumulative therapeutic success rate at 1-month posttreatment (61.0%) progressively increased to reach a range of 82.4% to 99.3% at 9-month posttreatment. The RSS mainly decreased in the first month of treatment in early responders. In early nonresponders, RSS progressively decreased throughout the 9-month treatment period. The baseline severity of RSS is a strong predictor of therapeutic response. CONCLUSION: A therapeutic regimen of 1 month can be sufficient to treat one third of LPRD patients. The early nonresponders may require 3 to 9 months of treatment

Generative artificial intelligence in otolaryngology-head and neck surgery editorial: be an actor of the future or follower.

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Treating and Managing Laryngopharyngeal Reflux Disease in the Over 65s: Evidence to Date.

peer reviewed[en] PURPOSE: The clinical presentation and therapeutic outcomes of elderly patients may be different from those in younger populations, leading to additional diagnostic and therapeutic difficulties. The present study reviewed the findings on the epidemiology, and clinical, diagnostic, and therapeutic outcomes of elderly patients with laryngopharyngeal reflux (LPR). METHODS: A PubMed, Cochrane Library, and Scopus literature search was conducted on the epidemiological, clinical, diagnostic, and therapeutic findings of elderly LPR patients. FINDINGS: The prevalence of LPR in the elderly population remains unknown. From a clinical standpoint, older LPR patients report overall lower symptom scores and related quality-of-life outcomes at the time of the diagnosis. The required treatment time to obtain symptom relief appears to be longer in older compared with younger patients. Particular attention needs to be paid to prolonged medication use because the elderly population is characterized by polypharmacy and there is a higher risk of proton-pump inhibitor (PPI) interactions and adverse events. The plasma clearance of most PPIs is reduced with age, which must be considered by practitioners in the prescription of antireflux therapy. CONCLUSION: The clinical presentation and treatment efficacy of elderly LPR patients differ from those in younger patients. Practitioners need to carefully consider the risk of drug interactions and adverse events in elderly patients

Sensitivity, Specificity, and Predictive Values of Laryngopharyngeal Reflux Symptoms and Signs in Clinical Practice.

peer reviewed[en] OBJECTIVE: To investigate the sensitivity (SE), specificity (SP), and positive and negative predictive value (PPV and NPV) of symptoms and signs of laryngopharyngeal reflux (LPR). STUDY DESIGN: Prospective controlled. SETTING: University medical center. METHODS: Patients presenting with LPR symptoms and signs were consecutively included after diagnosis confirmation through 24-hour hypopharyngeal-esophageal multichannel intraluminal impedance-pH monitoring. Healthy individuals were recruited to compose a control group. Symptoms and signs were evaluated with the reflux symptom score and reflux sign assessment. The SE, SP, PPV, and NPV of symptoms and signs were assessed. RESULTS: The study included 403 patients with LPR and 144 healthy individuals. Throat clearing, globus sensation, heartburn, and excess throat mucus were symptoms with the highest SE (67.5%-69.7%), SP (12.5%-20.8%), and NPV (48.3%-49.2%). The combination of throat clearing, heartburn, globus sensation, and excess throat mucus led to a high SE (96.0%) and NPV (85.2%). Anterior pillar erythema, tongue tonsil hypertrophy, and posterior commissure hypertrophy resulted in the highest SE (75.5%-83.5%). The highest SP was found for uvula erythema/edema, epiglottis erythema, and interarytenoid granulatory tissue (97.1%-97.2%). The association of nonendoscopic signs (anterior pillar erythema, uvula erythema/edema, and coated tongue) had an SE and SP of 80.1% and 47.2%, respectively. The association of throat clearing, heartburn, globus, anterior pillar erythema, and uvula erythema/edema had the highest SE (98.8%), SP (33.3%), PPV (94.3%), and NPV (70.6%). CONCLUSION: LPR symptoms and signs reported low SP and NPV. The SE, SP, PPV, and NPV may be maximized with the association of throat clearing, heartburn, globus sensation, anterior pillar erythema, and uvula erythema/edema

Pharmacological and Biological Relevance in the Medical Treatment of Laryngopharyngeal Reflux: A State-of-the-Art Review.

peer reviewedThe laryngopharyngeal reflux disease (LPRD) treatment remains controversial due to the poor effectiveness of proton pump inhibitors (PPIs). In this paper, the author reviewed the current primary treatments used in clinical studies for managing LPRD and discussed the pharmacological, biological, and physiological properties of medication for providing clinical relevance for otolaryngological practice. A comprehensive review of the PubMed, Cochrane Library, and Scopus literature was conducted to document and analyze the medical treatments of LPRD in the largest case series published in the past 20 years. Fifty-five studies met the inclusion criteria, revealing that 67 different therapeutic regimens were used in the LPRD studies in the past 20 years with nine different therapeutic durations. PPIs have been used as a single therapy in 70.1% of cases. PPIs were combined with another drug in 23.9% of cases. Alginates and antacids were used as single therapy or in association with other drugs in 10.5% and 3.0% of cases, respectively. There was an important variability of molecules, doses, and regimens. There is an important gap between current therapeutic practice and the recent advancements in the pathophysiology of LPRD. The pharmacological and physiological findings of this review can reasonably support the notion that alternative gastroesophageal reflux disease therapies (alginate, antacids) could take a significant place in the treatment of primary or recalcitrant LPRD. Future studies are needed to confirm the stability of the LPRD profile at the hypopharyngeal-esophageal multichannel intraluminal impedance-pH and the role of digestive enzymes in the development of upper aerodigestive tract mucosa inflammation and symptoms

Editorial letter: Artificial Intelligence can be used to improve the humanity of care.

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