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We describe the design and deployment of GREENBURST, a commensal Fast Radio Burst (FRB) search system at the Green Bank Telescope. GREENBURST uses the dedicated L-band receiver tap to search over the 960–1 920 MHz frequency range for pulses with dispersion measures out to
. Due to its unique design, GREENBURST is capable of conducting searches for FRBs when the L-band receiver is not being used for scheduled observing. This makes it a sensitive single pixel detector capable of reaching deeper in the radio sky. While single pulses from Galactic pulsars and rotating radio transients will be detectable in our observations, and will form part of the database we archive, the primary goal is to detect and study FRBs. Based on recent determinations of the all-sky rate, we predict that the system will detect approximately one FRB for every 2–3 months of continuous operation. The high sensitivity of GREENBURST means that it will also be able to probe the slope of the FRB fluence distribution, which is currently uncertain in this observing band.
Patient assessment is a fundamental feature of community paramedicine, but the absence of a recognized standard for assessment practices contributes to uncertainty about what drives care planning and treatment decisions. Our objective was to summarize the content of assessment instruments and describe the state of current practice in community paramedicine home visit programs.
We performed an environmental scan of all community paramedicine programs in Ontario, Canada, and used content analysis to describe current assessment practices in home visit programs. The International Classification on Functioning, Disability, and Health (ICF) was used to categorize and compare assessments. Each item within each assessment form was classified according to the ICF taxonomy.
A total of 43 of 52 paramedic services in Ontario, Canada, participated in the environmental scan with 24 being eligible for further investigation through content analysis of intake assessment forms. Among the 24 services, 16 met inclusion criteria for content analysis. Assessment forms contained between 13 and 252 assessment items (median 116.5, IQR 134.5). Most assessments included some content from each of the domains outlined in the ICF. At the subdomain level, only assessment of impairments of the functions of the cardiovascular, hematological, immunological, and respiratory systems appeared in all assessments.
Although community paramedicine home visit programs may differ in design and aim, all complete multi-domain assessments as part of patient intake. If community paramedicine home visit programs share similar characteristics but assess patients differently, it is difficult to expect that the resulting referrals, care planning, treatments, or interventions will be similar.
To propose a new classification of inner-ear anomalies that is more clinically oriented and surgically relevant: the SMS (Sawai Man Singh) classification of cochleovestibular malformations.
A retrospective multicentric study was conducted of 436 cochlear implantations carried out in 3 Indian tertiary care institutes. Patients with anomalous anatomy were included and classified, as per the new SMS classification, into cochleovestibular malformation types I, II, III and IV, based on cochlear morphology, modiolus and lamina cribrosa.
There were 19, 23, 8 and 4 patients with cochleovestibular malformation types I, II, III and IV, respectively. Two-year post-operative Meaningful Auditory Integration Scale scores were statistically analysed.
This new classification for inner-ear anomalies is a simpler, more practical, outcome-oriented classification that can be used to better plan the surgery. These merits make it a more uniform classification for recording results.
The aim of this study is to identify the types of community paramedicine programs and the training for each.
A systematic review of MEDLINE, Embase, grey literature, and bibliographies followed a search strategy using common community paramedicine terms. All studies published in English up to January 22, 2018, were captured. Screening and extraction were completed in duplicate by two independent reviewers. The Mixed Methods Appraisal Tool (MMAT) was used to assess studies’ methodological quality (full methodology on PROSPERO: CRD42017051774).
From 3,004 papers, there were 64 papers identified (58 unique community paramedicine programs). Of the papers with an appraisable study design (40.6%), the median MMAT score was 3 of 4 criteria met, suggesting moderate quality. Programs most often served frequent 911 callers (48.3%) and individuals at risk for emergency department admission, readmission, or hospitalization (41.4%); and 70.7% of programs were preventive home visits. Common services provided were home assessment (29.5%), medication management (39.7%), and referral and/or transport to community services (37.9%); and 77.6% of programs involved interprofessional collaboration. Community paramedicine training was described by 57% of programs and expanded upon traditional paramedicine training and emphasized technical skills. Study heterogeneity prevented meta-analysis.
Community paramedicine programs and training were diverse and allowed community paramedics to address a spectrum of population health and social needs. Training was poorly described. Enabling more programs to assess and report on program and training outcomes would support community paramedicine growth and the development of formalized training or education frameworks.
A nonparaxial investigation for propagation characteristics of q-Gaussian laser beam in rippled density plasma is studied by considering the relativistic nonlinearity. The field distribution in the medium is expressed in terms of q parameter and beam width parameter f. Nonlinear parabolic partial differential equation governing the evolution of complex envelope in slowly varying approximation is solved in a modulated density profile. Analytical theory of self-focusing including higher order terms in the expansion of dielectric function up to fourth order is developed and the variation of beam width parameter f with the distance of propagation for different parameters is studied. One may note that increased value of density ripple, laser intensity and depth of modulation, increases self-focusing whereas a lower value of q shows strong self-focusing. A comparative study between paraxial and nonparaxial study has also conducted. This study is useful for research in high energy density physics.
Here, we present initial results from the ALFABURST radio transient survey, which is currently running in a commensal mode with the ALFA receiver at the Arecibo telescope. We observed for a total of 1400 hours and have detected single pulses from known pulsars but did not detect any FRBs. The non-detection of FRBs is consistent with the current FRB sky rates.
In this paper, we prove some new reverse dynamic inequalities of Renaud- and Bennett-type on time scales. The results are established using the time scales Fubini theorem, the reverse Hölder inequality and a time scales chain rule.
A s-polarized short-pulse laser impinged obliquely on an overdense plasma slab is shown to produce very significant second harmonic in the direction of specular reflection and transmission. The laser induces a non-linear current on electrons, which is curl free. However, with sharp plasma boundary, it gives rise to electromagnetic radiation at the second harmonic. Our formalism includes multiple reflections of the incident and second-harmonic waves from both the front and rear surfaces. The present work includes finiteness of the slab. The normalized second-harmonic amplitude acquires a sharp peak at some specific angle of incidence for a particular set of parameters dependent on thickness of the slab and plasma density.
To study the presence of bacterial biofilm on the sinus mucosa of healthy individuals (controls) and patients with chronic rhinosinusitis with or without nasal polyposis.
An analytical, prospective and observational study was conducted. Tissue samples were obtained from the sinus mucosa. The bacteria were isolated and typified, and the material was examined for biofilm formation using tissue culture plate, Congo red agar detection and tube methods.
A total of 100 cases were analysed for the presence of biofilm. Bacterial biofilm was present in 26 of 50 disease group cases (52 per cent) and in 4 of 50 control group cases (8 per cent) (p < 0.01).
The presence of biofilm on the mucosa of chronic rhinosinusitis patients offers a possible cause for the persistent inflammation, and for antibiotics resistance and antimicrobial therapy failure. These findings could change the approach to treatment.
Mid-Infrared optofluidics based silicon sensor platforms are demonstrated. Silicon is a great candidate for mid-infrared optofluidics for the following reasons: (1) Silicon has a broad transmission window up to 7 um (2) Silicon offers CMOS compatible and monolithic fabrication (3) Silicon has high chemical resistance that can withstand high temperature, acid/base solution and organic solvents. (4) Silicon is a non-toxic environmentally friendly material. The fabricated mid-infrared optofluidic sensor can replace bulky instruments, such as FTIR, with a lab-on-a-chip system, while achieving much higher sensitivity.
One dimensional photonic crystal 1D-PhC silicon waveguide resonators with quality factor, Q∼105, are demonstrated at mid-infrared wavelengths between 2 um to 5 um. Silicon has several advantages for mid-infrared applications including its broad mid-infrared transmission spectrum which extends out to 9 um, CMOS compatible fabrication processing, and ease of electronic-photonic integration. The proposed resonators are composed of photonic crystal cavities with optimized (i) lattice parameter a, (ii) cavity width w and (iii) hole radius r. Finite difference time domain (FDTD) simulations are used to adjust these three parameters, a, w, and r, to select a resonant frequency of interest within the mid-infrared spectral range. Due to the high quality factor Q, these PhC silicon waveguide resonators have much higher sensitivity as chemical sensors and have the potential to replace bulky instruments such as an FTIR.
The point defect injection from arsenic precipitation was studied using boron marker layers and antimony doped superlattices. Comparisons of arsenic and germanium amorphizing implants showed similar boron marker layer diffusion enhancements after spike annealing. The results indicate that the end of range damage caused by the implants was the source of the diffusion enhancement. Additional annealing cycles showed that there was retardation in the diffusion enhancement of the boron marker layers for precipitation range arsenic implants. Antimony marker layers showed no diffusion enhancement due to vacancy injection. The results of the experiments indicate that arsenic-interstitial complexes are the cause of the decrease flux of interstitials to the bulk.
The effects of post-implant anneal conditions on the level of residual damage resulting from nitrogen and boron implants after different anneal processes are investigated using the Positron Annihilation Spectroscopy (PAS) technique. It is shown that after implantation there is a substantial defect concentration significantly below the range of the implants. However such damage is almost completely recovered after anneal in contrast with the damage close to the implant range point. Such residual damage has a strong effect on the electrical characteristics of double implanted bipolar transistors - principally though reduction in carrier mobility and lifetime. It is shown that the precise implant and anneal conditions play a strong role in the level of such damage and the subsequent electrical performance of bipolar devices.
We report ordinary <ε┴> and extra-ordinary <ε║> dielectric function data of 4H- and 6H-SiC from 0.7 to 9.0 eV. These data, which were obtained by with spectroscopic ellipsometry, are in good qualitative agreement with trends recently reported in ab initio calculations.
The implementation of SiC based sensors and electronics for operation in chemically harsh, high temperature environments depends on understanding the SiO2/SiC interface in field effect devices. We have developed a technique to fabricate wedge polished samples (angle ∼ 1×10−4 rad) that provides access to the SiO2/SiC interface via a surface sensitive probe such as xray photoelectron spectroscopy (XPS). Lateral scanning along the wedge is equivalent to depth profiling. Spatially resolved XPS images of the O 1s and Si 2p core levels were obtained of the interfacial region. Samples consist of device-quality thermally grown oxides on 4H-SiC single crystal substrates. The C 1s spectrum suggests the presence of a graphitic layer on the nominally bare SiC surface following thermal oxidation.
A number of F2-based plasma chemistries (NF3, SF6, PF5 and BF3) were investigated for high rate etching of SiC. The most advantageous of these is SF6, based on the high rate (0.6 μm · min−1) it achieves and its relatively low cost compared to NF3. The changes in electrical properties of the near-surface region are relatively minor when the incident ion energy is kept below approximately 75 eV. At a process pressure of 5 mTorr, the SiC etch rate falls-off by ∼15 % in 30 μm diameter via holes compared to larger diameter holes (> 60 μm diameter) or open areas on the mask.
An intrinsic defect spectrum, commonly observed after ion-implantation, electron, proton or neutron irradiation and even after SIMS measurements is investigated using photoluminescence techniques. The spectrum is associated with carbon related isoelec-tronic centers having a pseudodonor like behaviour. Vacancy-interstitial pair complexes are tentatively suggested as the defect centers responsible for this intrinsic spectrum.