A game-theoretic approach to transmitter covariance matrix design for broadband MIMO Gaussian interference channels

A game-theoretic approach to transmitter covariance matrix design for broadband MIMO Gaussian interference channels Anandkumar, A.J.G. Lambotharan, S. Chambers, J.A. Dept of Electron. & Electr. Eng., Loughborough Univ., Loughborough, UK This paper appears in: Statistical Signal Processing, 2009. SSP '09. IEEE/SP 15th Workshop on Publication Date: Aug. 31 2009-Sept. 3 2009 On page(s): 301 - 304 E-ISBN: 978-1-4244-2711-6 Location: Cardiff ISBN: 978-1-4244-2709-3 INSPEC Accession Number:10961923 Digital Object Identifier: 10.1109/SSP.2009.5278580 Current Version Published: 2009-10-06 Abstract A game-theoretic approach to the maximization of the information rates of broadband multi-input-multi-output (MIMO) Gaussian interference channels is proposed. The problem is cast as a strategic noncooperative game with the MIMO links as players and the information rates as payoff functions. The Nash equilibrium solution of this game is a waterfilling operation and sufficient conditions for its existence and uniqueness are presented. A distributed algorithm which requires no cooperation among the users is presented along with conditions for guaranteed global convergence of the proposed algorithm. The efficacy of the proposed scheme is confirmed through a design example

The Effects of Atmospheric Dispersion on High-Resolution Solar Spectroscopy

We investigate the effects of atmospheric dispersion on observations of the Sun at the ever-higher spatial resolutions afforded by increased apertures and improved techniques. The problems induced by atmospheric refraction are particularly significant for solar physics because the Sun is often best observed at low elevations, and the effect of the image displacement is not merely a loss of efficiency, but the mixing of information originating from different points on the solar surface. We calculate the magnitude of the atmospheric dispersion for the Sun during the year and examine the problems produced by this dispersion in both spectrographic and filter observations. We describe an observing technique for scanning spectrograph observations that minimizes the effects of the atmospheric dispersion while maintaining a regular scanning geometry. Such an approach could be useful for the new class of high-resolution solar spectrographs, such as SPINOR, POLIS, TRIPPEL, and ViSP

Far from just a poke : Common painful needle procedures and the development of needle fear

Background: Vaccine injections are the most common painful needle procedure experienced throughout the lifespan. Many strategies are available to mitigate this pain; however, they are uncommonly utilized, leading to unnecessary pain and suffering. Some individuals develop a high level of fear and subsequent needle procedures are associated with significant distress. Objective: The present work is part of an update and expansion of a 2009 knowledge synthesis to include the management of vaccinerelated pain across the lifespan and the treatment of individuals with high levels of needle fear. This article will provide a conceptual foundation for understanding: (a) painful procedures and their role in the development and maintenance of high levels of fear; (b) treatment strategies for preventing or reducing the experience of pain and the development of fear; and (c) interventions for mitigating high levels of fear once they are established. Results: First, the general definitions, lifespan development and functionality, needle procedure-related considerations, and assessment of the following constructs are provided: pain, fear, anxiety, phobia, distress, and vasovagal syncope. Second, the importance of unmitigated pain from needle procedures is highlighted from a developmental perspective. Third, the prevalence, course, etiology, and consequences of high levels of needle fear are described. Finally, the management of needle-related pain and fear are outlined to provide an introduction to the series of systematic reviews in this issue. Discussion: Through the body of work in this supplement, the authors aim to provide guidance in how to treat vaccination-related pain and its sequelae, including high levels of needle fear

Triple oxygen isotopic composition of the high-³He/⁴He mantle

Measurements of Xe isotope ratios in ocean island basalts (OIB) suggest that Earth’s mantle accreted heterogeneously, and that compositional remnants of accretion are sampled by modern, high-3He/4He OIB associated with the Icelandic and Samoan plumes. If so, the high-3He/4He source may also have a distinct oxygen isotopic composition from the rest of the mantle. Here, we test if the major elements of the high-3He/4He source preserve any evidence of heterogeneous accretion using measurements of three oxygen isotopes on olivine from a variety of high-3He/4He OIB locations. To high precision, the Δ17O value of high-3He/4He olivines from Hawaii, Pitcairn, Baffin Island and Samoa, are indistinguishable from bulk mantle olivine (Δ17OBulk Mantle − Δ17OHigh 3He/4He olivine = −0.002 ± 0.004 (2 × SEM)‰). Thus, there is no resolvable oxygen isotope evidence for heterogeneous accretion in the high-3He/4He source. Modelling of mixing processes indicates that if an early-forming, oxygen-isotope distinct mantle did exist, either the anomaly was extremely small, or the anomaly was homogenised away by later mantle convection. The δ18O values of olivine with the highest 3He/4He ratios from a variety of OIB locations have a relatively uniform composition (∼5‰). This composition is intermediate to values associated with the depleted MORB mantle and the average mantle. Similarly, δ18O values of olivine from high-3He/4He OIB correlate with radiogenic isotope ratios of He, Sr, and Nd. Combined, this suggests that magmatic oxygen is sourced from the same mantle as other, more incompatible elements and that the intermediate δ18O value is a feature of the high-3He/4He mantle source. The processes responsible for the δ18O signature of high-3He/4He mantle are not certain, but δ18O–87Sr/86Sr correlations indicate that it may be connected to a predominance of a HIMU-like (high U/Pb) component or other moderate δ18O components recycled into the high-3He/4He source

Oviposition Preference and Offspring Performance In Container Breeding Mosquitoes: Evaluating the Effects of Organic Compounds and Laboratory Colonisation

1. The preference–performance hypothesis (PPH) predicts that organisms lacking parental care should oviposit in habitats that optimise offspring performance. Preference–performance relationships were investigated for the Asian tiger mosquito (Aedes albopictus Skuse) and the southern house mosquito (Culex quinquefasciatus Say) (Diptera: Culicidae), two medically important container-breeding species, in response to an organic chemical blend mimicking decaying plant matter. Additionally, the effects of long-term laboratory colonisation of Cx. quinquefasciatus using wild and laboratory strains were evaluated. 2. Oviposition bioassays were conducted by releasing gravid mosquitoes into field enclosures with automobile tires containing low and high concentrations of the chemical blend, and water controls. The offspring were then reared in water collected from the tires in which they were deposited. 3. Aedes albopictus and wild Cx. quinquefasciatus laid more eggs in the chemical blend than water controls but did not differentiate between the low and high concentrations. Conversely, laboratory Cx. quinquefasciatus only preferred the high concentration to the low concentration. No statistical associations between oviposition preference and larval survival were found, as the chemical blend did not affect survivorship of either species. 4. The oviposition preference for the chemical blend over water controls suggests that both species oviposit in the best available resource environment, but further studies are needed before conclusions regarding preference–performance relationships can be drawn. 5. It was found that long-term laboratory colonisation affects the oviposition behaviour in Cx. quinquefasciatus, suggesting that behavioural studies on laboratory strains are not always applicable to wild populations

Quantum Oscillation Studies of the Fermi Surface of LaFePO

We review recent experimental measurements of the Fermi surface of the iron-pnictide superconductor LaFePO using quantum oscillation techniques. These studies show that the Fermi surface topology is close to that predicted by first principles density functional theory calculations, consisting of quasi-two-dimensional electron-like and hole-like sheets. The total volume of the two hole sheets is almost equal to that of the two electron sheets, and the hole and electron Fermi surface sheets are close to a nesting condition. No evidence for the predicted three dimensional pocket arising from the Fe $d_{z^2}$ band is found. Measurements of the effective mass suggest a renormalisation of around two, close to the value for the overall band renormalisation found in recent angle resolved photoemission measurements.Comment: Submitted to Physica C special issue on iron-pnictide superconductor

Psychological interventions for vaccine injections in children and adolescents: Systematic review of randomized and quasi-randomized controlled trials

Background: This systematic review evaluated the effectiveness of psychological interventions for reducing vaccination pain and related outcomes in children and adolescents. Design/Methods: Database searches identified relevant randomized and quasi-randomized controlled trials. Data were extracted and pooled using established methods. Pain, fear, and distress were considered critically important outcomes. Results: Twenty-two studies were included; 2 included adolescents. Findings showed no benefit of false suggestion (n=240) for pain (standardized mean difference [SMD] -0.21 [-0.47, 0.05]) or distress (SMD -0.28 [-0.59, 0.11]), or for use of repeated reassurance (n=82) for pain (SMD -0.18 [-0.92, 0.56]), fear (SMD -0.18 [-0.71, 0.36]), or distress (SMD 0.10 [-0.33, 0.54]). Verbal distraction (n=46) showed reduced distress (SMD -1.22 [-1.87, -0.58]), but not reduced pain (SMD -0.27 [-1.02, 0.47]). Similarly, video distraction (n=328) showed reduced distress (SMD -0.58 [-0.82, -0.34]), but not reduced pain (SMD -0.88 [-1.78, 0.02]) or fear (SMD 0.08 [-0.25, 0.41]). Music distraction demonstrated reduced pain when used with children (n=417) (SMD -0.45 [-0.71, -0.18]), but not with adolescents (n=118) (SMD -0.04 [-0.42, 0.34]). Breathing with a toy (n=368) showed benefit for pain (SMD -0.49 [-0.85, -0.13]), but not fear (SMD -0.60 [-1.22, 0.02]); whereas breathing without a toy (n=136) showed no benefit for pain (SMD -0.27 [-0.61, 0.07]) or fear (SMD -0.36 [-0.86, 0.15]). There was no benefit for a breathing intervention (cough) in children and adolescents (n=136) for pain (SMD -0.17 [-0.41, 0.07]). Conclusions: Psychological interventions with some evidence of benefit in children include: verbal distraction, video distraction, music distraction, and breathing with a toy

Process interventions for vaccine injections: Systematic review of randomized controlled trials and quasi-randomized controlled trials

Background: This systematic review evaluated the effectiveness of process interventions (education for clinicians, parent presence, education of parents [before and on day of vaccination], and education of patients on day of vaccination) on reducing vaccination pain, fear, and distress and increasing the use of interventions during vaccination. Design/Methods: Databases were searched using a broad search strategy to identify relevant randomized and quasi-randomized controlled trials. Critical outcomes were pain, fear, distress (when applicable), and use of pain management interventions. Data were extracted according to procedure phase (preprocedure, acute, recovery, combinations of these) and pooled using established methods. Analyses were conducted using standardized mean differences (SMD) and risk ratios (RR). Results: Thirteen studies were included. Results were generally mixed. On the basis of low to very low-quality evidence, the following specific critical outcomes showed significant effects suggesting: (1) clinicians should be educated about vaccine injection pain management (use of interventions: SMD 0.66; 95% confidence interval [CI]: 0.47, 0.85); (2) parents should be present (distress preprocedure: SMD -0.85; 95% CI: -1.35, -0.35); (3) parents should be educated before the vaccination day (use of intervention preprocedure: SMD 0.83; 95% CI: 0.25, 1.41 and RR, 2.08; 95% CI: 1.51, 2.86; distress acute: SMD, -0.35; 95% CI: -0.57, -0.13); (4) parents should be educated on the vaccination day (use of interventions: SMD 1.02; 95% CI: 0.22, 1.83 and RR, 2.42; 95% CI: 1.47, 3.99; distress preprocedure+acute+ recovery: SMD -0.48; 95% CI: -0.82, -0.15); and (5) individuals 3 years of age and above should be educated on the day of vaccination (fear preprocedure: SMD -0.67; 95% CI: -1.28, -0.07). Conclusions: Educating individuals involved in the vaccination procedure (clinicians, parents of children being vaccinated; individuals above 3 y of age) is beneficial to increase use of pain management strategies, reduce distress surrounding with vaccination, and to reduce fear. When possible, parent presence is also recommended for children undergoing vaccination

HELPinKids & Adults knowledge synthesis of the management of vaccination pain and high levels of needle fear limitations of the evidence and recommendations for future research

The HELPinKids&Adults knowledge synthesis for the management of vaccination-related pain and high levels of needle fear updated and expanded upon the 2010 HELPinKIDS knowledge synthesis and clinical practice guideline for pain mitigation during vaccine injections in childhood. Interventions for vaccine pain management in adults and treatment of individuals with high levels of needle fear, phobias, or both were included, thereby broadening the reach of this work. The present paper outlines the overarching limitations of this diverse evidence base and provides recommendations for future research. Consistent with the framing of clinical questions in the systematic reviews, the Participants, Intervention, Comparison, Outcome, Study design (PICOAS) framework was used to organize these predominant issues and research directions. The major limitations we identified across systematic reviews were an overall dearth of trials on vaccination, lack of methodological rigor, failure to incorporate important outcomes, poor study reporting, and various sources of heterogeneity. Future research directions in terms of conducting additional trials in the vaccination context, improving methodological quality and rigor, assessment of global acceptability and feasibility of interventions, and inclusion of outcomes that stakeholders consider to be important (eg, compliance) are recommended. Given concerns about pain and fear are known contributors to vaccine hesitancy, improving and expanding this evidence base will be integral to broader efforts to improve vaccine compliance and public health worldwide

Interventions for individuals with high levels of needle fear: Systematic review of randomized controlled trials and quasi-randomized controlled trials

Background: This systematic review evaluated the effectiveness of exposure-based psychological and physical interventions for the management of high levels of needle fear and/or phobia and fainting in children and adults. Design/Methods: A systematic review identified relevant randomized and quasi-randomized controlled trials of children, adults, or both with high levels of needle fear, including phobia (if not available, then populations with other specific phobias were included). Critically important outcomes were self-reported fear specific to the feared situation and stimulus (psychological interventions) or fainting (applied muscle tension). Data were pooled using standardized mean difference (SMD) or relative risk with 95% confidence intervals. Results: The systematic review included 11 trials. In vivo exposurebased therapy for children 7 years and above showed benefit on specific fear (n=234; SMD: -1.71 [95% CI: -2.72, -0.7]). In vivo exposure-based therapy with adults reduced fear of needles posttreatment (n=20; SMD: -1.09 [-2.04, -0.14]) but not at 1-year follow-up (n=20; SMD: -0.28 [-1.16, 0.6]). Compared with single session, a benefit was observed for multiple sessions of exposure-based therapy posttreatment (n=93; SMD: -0.66 [-1.08, -0.24]) but not after 1 year (n=83; SMD: -0.37 [-0.87, 0.13]). Non in vivo e.g., imaginal exposure-based therapy in children reduced specific fear posttreatment (n=41; SMD: -0.88 [-1.7, -0.05]) and at 3 months (n=24; SMD: -0.89 [-1.73, -0.04]). Non in vivo exposure-based therapy for adults showed benefit on specific fear (n=68; SMD: -0.62 [-1.11, -0.14]) but not procedural fear (n=17; SMD: 0.18 [-0.87, 1.23]). Applied tension showed benefit on fainting posttreatment (n=20; SMD: -1.16 [-2.12, -0.19]) and after 1 year (n=20; SMD: -0.97 [-1.91, -0.03]) compared with exposure alone. Conclusions: Exposure-based psychological interventions and applied muscle tension show evidence of benefit in the reduction of fear in pediatric and adult populations