3,438 research outputs found

    Large Signal Analysis of a New Meander Line Topology for W-band Traveling Wave Tubes

    Get PDF
    Satellite distribution of high data rate needs wide frequency band. The millimeter waves, in particular the W-band, provide wide bandwidth and relatively low attenuation. The link transmission power can be provided only by Traveling Wave Tubes (TWTs). A new meander line topology to be used as slow wave structure for 71-76 GHz TWTs, with improved performance in comparison to the conventional one, is proposed. The new meander line compared to a standard meander line shows flatter gain and higher output power. © 2019 IEEE

    Statewide retrospective study of low acuity emergency presentations in New South Wales, Australia: who, what, where and why?

    Get PDF
    This is an Open Access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/Abstract Objective The present study aims to use a statewide population-based registry to assess the prevalence of low acuity emergency department (ED) presentations, describe the trend in presentation rates and to determine whether they were associated with various presentation characteristics such as the type of hospital as well as clinical and demographic variables. Design and setting This was a retrospective analysis of a population-based registry of ED presentations in New South Wales (NSW). Generalised estimating equations with log links were used to determine factors associated with low acuity presentations to account for repeat presentations and the possibility of clustering of outcomes. Participants Patients were included in this analysis if they presented to an ED between January 2010 and December 2014. The outcomes of interest were low acuity presentation, defined as those who self-presented (were not transported by ambulance), were assigned a triage category of 4 or 5 (semiurgent or non-urgent) and discharged back to usual residence from ED. Results There were 10.7 million ED presentations analysed. Of these, 45% were classified as a low acuity presentation. There was no discernible increase in the rate of low acuity presentations across NSW between 2010 and 2014. The strongest predictors of low acuity ED presentation were age <40 years of age (OR 1.77); injury or musculoskeletal administrative and non-urgent procedures (OR 2.96); ear, nose and throat, eye or oral (OR 5.53); skin or allergy-type presenting problems (OR 2.84). Conclusions Low acuity ED presentations comprise almost half of all ED presentations. Alternative emergency models of care may help meet the needs of these patients

    Maxillary arch development with Invisalign system: Analysis of expansion dental movements on digital dental casts

    Get PDF
    Objectives: To evaluate tooth movements during maxillary arch expansion with clear aligner treatment.Materials and Methods: The study group included 28 subjects (16 females, 12 males, mean age 31.9 +/- 5.4 years) collected prospectively from January 2018 to May 2019. Inclusion criteria were European ancestry, posterior transverse discrepancy of 3-6 mm, permanent dentition stage, presence of second permanent molars, mild or moderate crowding, and good compliance with aligners. Treatment protocol included nonextraction strategies, application of Invisalign clear aligner system, and no auxiliaries other than Invisalign attachments. Linear and angular measurements were performed before treatment (T1), at the end of treatment (T2), and on final virtual models (T2 ClinCheck). A paired t-test was used to compare T2-T1 and T2-T2 ClinCheck changes. The level of significance was set at 5%.Results: Statistically significant differences were found for all measurements, except for ones at the upper second molars. The greatest increase in maxillary width was detected at the upper first and second premolars: 13.5 mm for the first premolar and 13.8 mm for the second premolar at T2. Comparison of T2-T1 angular outcomes showed statistically significant changes in the inclinations of all teeth except for the second permanent molars. T2-T2 ClinCheck showed significant differences for both linear and angular measurements for maxillary canines, resulting in poor predictability.Conclusions: Maxillary arch development revealed a progressive reduction of the expansion rate and buccal tipping in the anterior, lateral, and posterior regions, with the greatest net increase at the first and second premolars. Clinical attention should be paid to maxillary canine movements, and overcorrection should be planned for them during dentoalveolar expansion

    Idiopathic facial palsy: umbrella review of systematic reviews and meta-analyses

    Get PDF
    Idiopathic facial palsy is the most common disease of the VII cranial nerve. There are many treatments to facilitate recovery from this condition: pharmacological, surgical, rehabilitative, but the effectiveness of some of these treatments, especially the latter, is still under discussion. The purpose of this umbrella review of systematic reviews is to analyse the literature in order to investigate the different rehabilitation interventions in patients suffering from idiopathic facial palsy. A scientific literature search was carried out from January 2009 until August 2019, using Mesh the terms "facial palsy", "Bell's Palsy", "idiopathic facial nerve palsy", combined with "rehabilitation" and "therapy". Initially all the systematic reviews and meta-analyses of the last 10 years concerning rehabilitation treatments for the recovery of injured functions in facial palsy were included. Given the heterogeneity of the studies in the literature, which do not differentiate the different causes of facial palsy, all the causes of idiopathic facial palsy were included in the review. The research resulted in 94 published systematic reviews but only 6 were considered in respect to the inclusion criteria. All studies agree on the lack of high-quality scientific work to be able to say that Bell's physiotherapy treatments for facial palsy are effective, in particular with regard to recovery times during the rehabilitation process. Future studies are needed, in order to highlight the therapeutic implications of the different rehabilitation methods, with standardized protocols, in patients suffering from facial palsy of different aetiology

    The OPERA magnetic spectrometer

    Full text link
    The OPERA neutrino oscillation experiment foresees the construction of two magnetized iron spectrometers located after the lead-nuclear emulsion targets. The magnet is made up of two vertical walls of rectangular cross section connected by return yokes. The particle trajectories are measured by high precision drift tubes located before and after the arms of the magnet. Moreover, the magnet steel is instrumented with Resistive Plate Chambers that ease pattern recognition and allow a calorimetric measurement of the hadronic showers. In this paper we review the construction of the spectrometers. In particular, we describe the results obtained from the magnet and RPC prototypes and the installation of the final apparatus at the Gran Sasso laboratories. We discuss the mechanical and magnetic properties of the steel and the techniques employed to calibrate the field in the bulk of the magnet. Moreover, results of the tests and issues concerning the mass production of the Resistive Plate Chambers are reported. Finally, the expected physics performance of the detector is described; estimates rely on numerical simulations and the outcome of the tests described above.Comment: 6 pages, 10 figures, presented at the 2003 IEEE-NSS conference, Portland, OR, USA, October 20-24, 200

    The Sydney Triage to Admission Risk Tool (START) to predict Emergency Department Disposition: A derivation and internal validation study using retrospective state-wide data from New South Wales, Australia.

    Full text link
    BACKGROUND: Disposition decisions are critical to the functioning of Emergency Departments. The objectives of the present study were to derive and internally validate a prediction model for inpatient admission from the Emergency Department to assist with triage, patient flow and clinical decision making. METHODS: This was a retrospective analysis of State-wide Emergency Department data in New South Wales, Australia. Adult patients (age ≄ 16 years) were included if they presented to a Level five or six (tertiary level) Emergency Department in New South Wales, Australia between 2013 and 2014. The outcome of interest was in-patient admission from the Emergency Department. This included all admissions to short stay and medical assessment units and being transferred out to another hospital. Analyses were performed using logistic regression. Discrimination was assessed using area under curve and derived risk scores were plotted to assess calibration. RESULTS: 1,721,294 presentations from twenty three Level five or six hospitals were analysed. Of these 49.38% were male and the mean (sd) age was 49.85 years (22.13). Level 6 hospitals accounted for 47.70% of cases and 40.74% of cases were classified as an in-patient admission based on their mode of separation. The final multivariable model including age, arrival by ambulance, triage category, previous admission and presenting problem had an AUC of 0.82 (95% CI 0.81, 0.82). CONCLUSION: By deriving and internally validating a risk score model to predict the need for in-patient admission based on basic demographic and triage characteristics, patient flow in ED, clinical decision making and overall quality of care may be improved. Further studies are now required to establish clinical effectiveness of this risk score model

    Integration of focal vibration and intra-articular oxygen–ozone therapy in rehabilitation of painful knee osteoarthritis

    Get PDF
    Objective: To examine the pain-reducing effects of intra-articular oxygen–ozone (O2O3) injections and mechanical focal vibration (mFV) versus O2O3 injections alone in patients with knee osteoarthritis. Methods: Patients with chronic pain (&gt;6 weeks) due to knee osteoarthritis (II–III on the Kellgren–Lawrence scale) were consecutively enrolled and divided into two groups: O2O3 (n = 25) and O2O3-mFV (n = 24). The visual analog scale (VAS), Knee Injury and Osteoarthritis Outcome Score (KOOS), and Medical Research Council (MRC) Manual Muscle Testing scale were administered at baseline (before treatment), after 3 weeks of treatment, and 1 month after the end of treatment. Patients received three once-weekly intra-articular injections of O2O3 into the knee (20 mL O3, 20 ÎŒg/mL). The O2O3-mFV group also underwent nine sessions of mFV (three sessions per week). Results: The VAS score, KOOS, and MRC score were significantly better in the O2O3-mFV than O2O3 group. The within-group analysis showed that all scores improved over time compared with baseline and were maintained even 1 month after treatment. No adverse events occurred. Conclusion: An integrated rehabilitation protocol involving O2O3 injections and mFV for 3 weeks reduces pain, increases autonomy in daily life activities, and strengthens the quadriceps femoris
    • 

    corecore