Naresuan University Journal
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Spatial-correlations and load-awareness in heterogeneous networks
No full textWe present a new unified model for the design and analysis of load-aware downlink heterogeneous networks (HetNets) where interferers are inherently spatially-correlated. A closed-form expression for the aggregate network interference statistics generated by correlated load-proportional tiers of base stations (BSs) over Nakagami-m fading interfering channels is developed. This approach allows for relaxation of several major limitations in the existing state-of-the-art models, in particular the always-on-BSs, uncorrelated interferers, and Rayleigh fading with no shadowing assumptions. The validity and advantages of the proposed load-aware framework over the heavily-adopted fully-loaded model and the more recent interference-thinning-based approximation are confirmed via extensive Monte-Carlo (MC) simulations. The results reveal several important trends and design guidelines for the practical deployment of HetNets
Natural asynchronies in audiovisual communication signals regulate neuronal multisensory interactions in voice-sensitive cortex
No full textWhen social animals communicate, the onset of informative content in one modality varies considerably relative to the other, such as when visual orofacial movements precede a vocalization. These naturally occurring asynchronies do not disrupt intelligibility or perceptual coherence. However, they occur on time scales where they likely affect integrative neuronal activity in ways that have remained unclear, especially for hierarchically downstream regions in which neurons exhibit temporally imprecise but highly selective responses to communication signals. To address this, we exploited naturally occurring face- and voice-onset asynchronies in primate vocalizations. Using these as stimuli we recorded cortical oscillations and neuronal spiking responses from functional MRI (fMRI)-localized voice-sensitive cortex in the anterior temporal lobe of macaques. We show that the onset of the visual face stimulus resets the phase of low-frequency oscillations, and that the face-voice asynchrony affects the prominence of two key types of neuronal multisensory responses: enhancement or suppression. Our findings show a three-way association between temporal delays in audiovisual communication signals, phase-resetting of ongoing oscillations, and the sign of multisensory responses. The results reveal how natural onset asynchronies in cross-sensory inputs regulate network oscillations and neuronal excitability in the voice-sensitive cortex of macaques, a suggested animal model for human voice areas. These findings also advance predictions on the impact of multisensory input on neuronal processes in face areas and other brain regions
The Herschel Virgo Cluster Survey. XVII. SPIRE point-source catalogs and number counts
No full textAims. We present three independent catalogs of point-sources extracted from SPIRE images at 250, 350, and 500 μm, acquired with the Herschel Space Observatory as a part of the Herschel Virgo Cluster Survey (HeViCS). The catalogs have been cross-correlated to consistently extract the photometry at SPIRE wavelengths for each object. Methods. Sources have been detected using an iterative loop. The source positions are determined by estimating the likelihood to be a real source for each peak on the maps, according to the criterion defined in the sourceExtractorSussextractor task. The flux densities are estimated using the sourceExtractorTimeline, a timeline-based point source fitter that also determines the fitting procedure with the width of the Gaussian that best reproduces the source considered. Afterwards, each source is subtracted from the maps, removing a Gaussian function in every position with the full width half maximum equal to that estimated in sourceExtractorTimeline. This procedure improves the robustness of our algorithm in terms of source identification. We calculate the completeness and the flux accuracy by injecting artificial sources in the timeline and estimate the reliability of the catalog using a permutation method. Results. The HeViCS catalogs contain about 52 000, 42 200, and 18 700 sources selected at 250, 350, and 500 μm above 3σ and are ~75%, 62%, and 50% complete at flux densities of 20 mJy at 250, 350, 500 μm, respectively. We then measured source number counts at 250, 350, and 500 μm and compare them with previous data and semi-analytical models. We also cross-correlated the catalogs with the Sloan Digital Sky Survey to investigate the redshift distribution of the nearby sources. From this cross-correlation, we select ~2000 sources with reliable fluxes and a high signal-to-noise ratio, finding an average redshift z ~ 0.3 ± 0.22 and 0.25 (16–84 percentile). Conclusions. The number counts at 250, 350, and 500 μm show an increase in the slope below 200 mJy, indicating a strong evolution in number of density for galaxies at these fluxes. In general, models tend to overpredict the counts at brighter flux densities, underlying the importance of studying the Rayleigh-Jeans part of the spectral energy distribution to refine the theoretical recipes of the models. Our iterative method for source identification allowed the detection of a family of 500 μm sources that are not foreground objects belonging to Virgo and not found in other catalogs
Why do patients with stroke not receive the recommended amount of active therapy (ReAcT)? Study protocol for a multisite case study investigation
No full textIntroduction Increased frequency and intensity of inpatient therapy contributes to improved outcomes for stroke survivors. Differences exist in the amount of therapy provided internationally. In England, Wales and Northern Ireland it is recommended that a minimum of 45 min of each active therapy should be provided at least 5 days a week provided the therapy is appropriate and that the patient can tolerate this. Sentinel Stroke National Audit Programme (2014) data demonstrate this standard is not being achieved for most patients. No research been undertaken to explore how therapists in England manage their practice to meet time-specific therapy recommendations. The ReAcT study aims to develop an in-depth understanding of stroke therapy provision, including how the guideline of 45 min a day of each relevant therapy, is interpreted and implemented by therapists, and how it is experienced by stroke-survivors and their families.Methods and analysis A multisite ethnographic case study design in a minimum of six stroke units will include modified process mapping, observations of service organisation, therapy delivery and documentary analysis. Semistructured interviews with therapists and service managers (n=90), and with patients and informal carers (n=60 pairs) will be conducted. Data will be analysed using the Framework approach.Ethics and dissemination The study received a favourable ethical opinion via the National Research Ethics Service (reference number: 14/NW/0266). Participants will provide written informed consent or, where stroke-survivors lack capacity, a consultee declaration will be sought. ReAcT is designed to generate insights into the organisational, professional, social, practical and patient-related factors acting as facilitators or barriers to providing the recommended amount of therapy. Provisional recommendations will be debated in consensus meetings with stakeholders who have not participated in ReAcT case studies or interviews. Final recommendations will be disseminated to therapists, service managers, clinical guideline developers and policymakers and stroke-survivors and informal carers
Real time Inverted Pendulum Sonified with SuperCollider.
No full textA real-time state space inverted pendulum was implemented in SuperCollider, then excited and sonified in real time
Evolution of a laser shock peened residual stress field locally with foreign object damage and subsequent fatigue crack growth
No full textForeign object damage (FOD) can seriously shorten the fatigue lives of components. On the other hand, laser shock peening improves fatigue life by introducing deep compressive residual stress into components. In this paper we examine how the non-uniform steep residual stress profile arising from FOD of laser peened aerofoil leading edges varies as a function of fatigue crack growth under high cycle fatigue and mixed high and low cycle fatigue conditions. The ballistic FOD impacts were introduced by impacting a cube edge head-on (at an angle of 0°) to the leading edge. The residual stress distributions have been mapped by synchrotron X-ray diffraction prior to cracking and subsequent to short (∼1 mm) and long (up to 6 mm) crack growth. The results suggest that the local residual stress field is highly stable even to the growth of relatively long cracks
Mutations in LZTR1 add to the complex heterogeneity of schwannomatosis
No full textOBJECTIVES: We aimed to determine the proportion of individuals in our schwannomatosis cohort whose disease is associated with an LZTR1 mutation. METHODS: We used exome sequencing, Sanger sequencing, and copy number analysis to screen 65 unrelated individuals with schwannomatosis who were negative for a germline NF2 or SMARCB1 mutation. We also screened samples from 39 patients with a unilateral vestibular schwannoma (UVS), plus at least one other schwannoma, but who did not have an identifiable germline or mosaic NF2 mutation. RESULTS: We identified germline LZTR1 mutations in 6 of 16 patients (37.5%) with schwannomatosis who had at least one affected relative, 11 of 49 (22%) sporadic patients, and 2 of 39 patients with UVS in our cohort. Three germline mutation-positive patients in total had developed a UVS. Mosaicism was excluded in 3 patients without germline mutation in NF2, SMARCB1, or LZTR1 by mutation screening in 2 tumors from each. CONCLUSIONS: Our data confirm the relationship between mutations in LZTR1 and schwannomatosis. They indicate that germline mutations in LZTR1 confer an increased risk of vestibular schwannoma, providing further overlap with NF2, and that further causative genes for schwannomatosis remain to be identified
Coulomb gluons and the ordering variable
No full textWe study in detail the exchange of a Coulomb (Glauber) gluon in the first few orders of QCD perturbation theory in order to shed light on their accounting to all orders. We find an elegant cancellation of graphs that imposes a precise ordering on the transverse momentum of the exchanged Coulomb gluon
Euclid \& {SKA} {Synergies}
No full textOver the past few years two of the largest and highest fidelity experiments conceived have been approved for construction: Euclid is an ESA M-Class mission that will map three-quarters of the extra galactic sky with Hubble Space Telescope resolution optical and NIR imaging, and NIR spectroscopy, its scientific aims (amongst others) are to create a map of the dark Universe and to determine the nature of dark energy. The Square Kilometre Array (SKA) has similar scientific aims (and others) using radio wavelength observations. The two experiments are synergistic in several respects, both through the scientific objectives and through the control of systematic effects. SKA Phase-1 and Euclid will be commissioned on similar timescales offering an exciting opportunity to exploit synergies between these facilities