Low-frequency gravitational-wave experiments require the highest timing precision from an array of the most stable millisecond pulsars. Several known sources of noise on short timescales in single ...radio pulsar observations are well described by a simple model of three components: template fitting from a finite signal-to-noise ratio, pulse phase/amplitude jitter from single-pulse stochasticity, and scintillation errors from short-timescale interstellar scattering variations. Currently template-fitting errors dominate, but as radio telescopes push toward higher signal-to-noise ratios, jitter becomes the next dominant term for most millisecond pulsars. Understanding the statistics of jitter becomes crucial for properly characterizing arrival time uncertainties. We characterize the radio frequency dependence of jitter using data on 48 pulsars in the North American Nanohertz Observatory for Gravitational Waves timing program. We detect significant jitter in 43 of the pulsars and test several functional forms for its frequency dependence; we find significant frequency dependence for 30 pulsars. We find moderate correlations of rms jitter with pulse width (R = 0.62) and number of profile components (R = 0.40); the single-pulse rms jitter is typically 1% of pulse phase. The average frequency dependence for all pulsars using a power-law model has index −0.42. We investigate the jitter variations for the interpulse of PSR B1937+21 and find no significant deviations from the main pulse rms jitter. We also test the time variation of jitter in two pulsars and find that systematics likely bias the results for high-precision pulsars. Pulsar timing array analyses must properly model jitter as a significant component of the noise within the detector.
The INT/WFC Photometric H... Survey of the Northern Galactic Plane (IPHAS) is a 1800 deg... imaging survey covering Galactic latitudes |b| < 5... and longitudes ... = 30...-215... in the r, i, and Hα ...filters using the Wide Field Camera (WFC) on the 2.5-m Isaac Newton Telescope (INT) in La Palma. We present the first quality-controlled and globally calibrated source catalogue derived from the survey, providing single-epoch photometry for 219 million unique sources across 92 per cent of the footprint. The observations were carried out between 2003 and 2012 at a median seeing of 1.1 arcsec (sampled at 0.33 arcsec pixel...) and to a mean 5... depth of 21.2 (r), 20.0 (i), and 20.3 (Hα) in the Vega magnitude system. We explain the data reduction and quality control procedures, describe and test the global re-calibration, and detail the construction of the new catalogue. We show that the new calibration is accurate to 0.03 mag (root mean square) and recommend a series of quality criteria to select accurate data from the catalogue. Finally, we demonstrate the ability of the catalogue's unique (r - Hα,...r - i) diagram to (i) characterize stellar populations and extinction regimes towards different Galactic sightlines and (ii) select and quantify Hα emission-line objects. IPHAS is the first survey to offer comprehensive CCD photometry of point sources across the Galactic plane at visible wavelengths, providing the much-needed counterpart to recent infrared surveys. (ProQuest: ... denotes formulae/symbols omitted.)
The introduction of hydrogen chloride during the in situ doping of silicon nanowires (SiNWs) grown using the vapor-liquid-solid (VLS) mechanism was investigated. Compared with non-chlorinated ...atmospheres, the use of HCl with dopant gases considerably improves the surface morphology of the SiNWs, leading to extremely smooth surfaces and a greatly reduced tapering. Variations in the wire diameter are massively reduced for boron doping, and cannot be measured at 600 °C for phosphorous over several tens of micrometers. This remarkable feature is accompanied by a frozen gold migration from the catalyst, with no noticeable levels of gold clusters observed using scanning electron microscopy. A detailed study of the apparent resistivity of the NWs reveals that the dopant incorporation is effective for both types of doping. A graph linking the apparent resistivity to the dopant to silane dilution ratio is built for both types of doping and discussed in the frame of the previous results.
To evaluate the efficacy of pegylated interferon (PEG-IFN) alpha-2a to treat post-uveitic relapsing macular edema (ME) after withdrawal of non-PEG IFN alpha-2a or 2b to maintain treatment efficacy.
...This retrospective study investigated subjects with post-uveitic ME who received weekly subcutaneous PEG-IFN alpha-2a injections. Comparisons between baseline central macular thickness (CMT) and best-corrected visual acuity (BCVA) and those at all follow-up visits were made.
Six patients (nine eyes) were treated and followed up for six months. CMT (mean standard deviation) decreased from 375117 to 28339 μm after one month (p < 0.001), remaining significantly lower up to the final follow-up visit at six months (27538 μm, p = 0.008), and BCVA (0.210.16 logMAR at baseline) showed an improvement of 0.120.11 logMAR (p = 0.026) at six months. Neither recurrences nor any serious adverse events were recorded.
Post-uveitic ME patients were effectively and safely treated with PEG-IFN alpha-2a.
An ensemble of inspiraling supermassive black hole binaries should produce a stochastic background of very low frequency gravitational waves. This stochastic background is predicted to be a power ...law, with a gravitational-wave strain spectral index of −2/3, and it should be detectable by a network of precisely timed millisecond pulsars, widely distributed on the sky. This paper reports a new "time slicing" analysis of the 11 yr data release from the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) using 34 millisecond pulsars. Methods to flag potential "false-positive" signatures are developed, including techniques to identify responsible pulsars. Mitigation strategies are then presented. We demonstrate how an incorrect noise model can lead to spurious signals, and we show how independently modeling noise across 30 Fourier components, spanning NANOGrav's frequency range, effectively diagnoses and absorbs the excess power in gravitational-wave searches. This results in a nominal, and expected, progression of our gravitational-wave statistics. Additionally, we show that the first interstellar medium event in PSR J1713+0747 pollutes the common red-noise process with low spectral index noise, and we use a tailored noise model to remove these effects.
The North American Nanohertz Observatory for Gravitational Waves (NANOGrav) has observed dozens of millisecond pulsars for over a decade. We have accrued a large collection of dispersion measure (DM) ...measurements sensitive to the total electron content between Earth and the pulsars at each observation. All lines of sight cross through the solar wind (SW), which produces correlated DM fluctuations in all pulsars. We develop and apply techniques for extracting the imprint of the SW from the full collection of DM measurements in the recently released NANOGrav 11 yr data set. We filter out long-timescale DM fluctuations attributable to structure in the interstellar medium and carry out a simultaneous analysis of all pulsars in our sample that can differentiate the correlated signature of the wind from signals unique to individual lines of sight. When treating the SW as spherically symmetric and constant in time, we find the electron number density at 1 au to be 7.9 0.2 cm−3. We find our data to be insensitive to long-term variation in the density of the wind. We argue that our techniques paired with a high-cadence, low-radio-frequency observing campaign of near-ecliptic pulsars would be capable of mapping out large-scale latitudinal structure in the wind.
•Growing silicon nanowires in porous alumina enables to increase their density.•Electrode capacitance is increased thanks to the SiNWs growth in alumina template.•SiNWs/SiNWs micro-supercapacitors ...have a promising stability in ionic liquid.
The use of nanoporous anodic alumina as a template for silicon nanowire growth enables the production of ultra dense nanowire arrays with density up to 8.109cm−2. The integration of such nanowire arrays in micro-supercapacitor electrodes significantly improves the electrode capacitance per planar surface area and nanowires length unit compared to electrodes made from silicon nanowires grown from gold colloids (from 5.2μF.cm−2.μm to 36.7μF.cm−2.μm). Micro-supercapacitors with such electrodes and ionic liquid as electrolyte have a very promising cycling stability featuring less than 1% of losses after 300 000 cycles.
Epidemiology of Pediatric Uveitis Gentile, P; Ragusa, E; Bolletta, E ...
Ocular immunology and inflammation
31, Številka:
10
Journal Article
Recenzirano
Uveitis is uncommon in children and its diagnosis and treatment are challenging. Little is known of the epidemiology of pediatric uveitis. Indeed, population-based studies in the literature are rare. ...However, there are many tertiary referral center reports that describe the patterns of uveitis in childhood, although few are from developed countries, and their comparison presents some issues. Anterior uveitis is the most frequent entity worldwide, especially in Western countries, where juvenile idiopathic arthritis is diffuse. Most cases of intermediate uveitis do not show any association with infectious or noninfectious systemic diseases. In low- and middle-income countries, posterior uveitis and panuveitis are prevalent due to the higher rates of infectious etiologies and systemic diseases such as Behçet disease and Vogt-Koyanagi-Harada disease. In recent decades, idiopathic uveitis rate has decreased thanks to diagnostic improvements.
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