Galaxy and Mass Assembly (GAMA): Demonstrating the power of WISE in the study of Galaxy Groups to z < 0.1

Combining high-fidelity group characterisation from the Galaxy and Mass Assembly (GAMA) survey and source-tailored z < 0.1 photometry from the WISE survey, we present a comprehensive study of the properties of ungrouped galaxies, compared to 497 galaxy groups (4≤ NFoF ≤ 20) as a function of stellar and halo mass. Ungrouped galaxies are largely unimodal in WISE color, the result of being dominated by star-forming, late-type galaxies. Grouped galaxies, however, show a clear bimodality in WISE color, which correlates strongly with stellar mass and morphology. We find evidence for an increasing earlytype fraction, in stellar mass bins between 1010 .Mstellar . 1011 M , with increasing halo mass. Using ungrouped, late-type galaxies with star-forming colors (W2−W3>3), we define a star-forming mainsequence (SFMS), which we use to delineate systems that have moved below the sequence (“quenched” for the purposes of this work). We find that with increasing halo mass, the relative number of latetype systems on the SFMS decreases, with a corresponding increase in early-type, quenched systems at high stellar mass (Mstellar > 1010.5 M ), consistent with mass quenching. Group galaxies with masses Mstellar < 1010.5 M show evidence of quenching consistent with environmentally-driven processes. The stellar mass distribution of late-type, quenched galaxies suggests they may be an intermediate population as systems transition from being star-forming and late-type to the “red sequence”. Finally, we use the projected area of groups on the sky to extract groups that are (relatively) compact for their halo mass. Although these show a marginal increase in their proportion of high mass and early-type galaxies compared to nominal groups, a clear increase in quenched fraction is not evident

Amplitude to phase conversion of InGaAs pin photo-diodes for femtosecond lasers microwave signal generation

When a photo-diode is illuminated by a pulse train from a femtosecond laser, it generates microwaves components at the harmonics of the repetition rate within its bandwidth. The phase of these components (relative to the optical pulse train) is known to be dependent on the optical energy per pulse. We present an experimental study of this dependence in InGaAs pin photo-diodes illuminated with ultra-short pulses generated by an Erbium-doped fiber based femtosecond laser. The energy to phase dependence is measured over a large range of impinging pulse energies near and above saturation for two typical detectors, commonly used in optical frequency metrology with femtosecond laser based optical frequency combs. When scanning the optical pulse energy, the coefficient which relates phase variations to energy variations is found to alternate between positive and negative values, with many (for high harmonics of the repetition rate) vanishing points. By operating the system near one of these vanishing points, the typical amplitude noise level of commercial-core fiber-based femtosecond lasers is sufficiently low to generate state-of-the-art ultra-low phase noise microwave signals, virtually immune to amplitude to phase conversion related noise.Comment: 7 pages, 6 figures, submitted to Applied Physics

The Flare-energy Distributions Generated by Kink-unstable Ensembles of Zero-net-current Coronal Loops

It has been proposed that the million degree temperature of the corona is due to the combined effect of barely-detectable energy releases, so called nanoflares, that occur throughout the solar atmosphere. Alas, the nanoflare density and brightness implied by this hypothesis means that conclusive verification is beyond present observational abilities. Nevertheless, we investigate the plausibility of the nanoflare hypothesis by constructing a magnetohydrodynamic (MHD) model that can derive the energy of a nanoflare from the nature of an ideal kink instability. The set of energy-releasing instabilities is captured by an instability threshold for linear kink modes. Each point on the threshold is associated with a unique energy release and so we can predict a distribution of nanoflare energies. When the linear instability threshold is crossed, the instability enters a nonlinear phase as it is driven by current sheet reconnection. As the ensuing flare erupts and declines, the field transitions to a lower energy state, which is modelled by relaxation theory, i.e., helicity is conserved and the ratio of current to field becomes invariant within the loop. We apply the model so that all the loops within an ensemble achieve instability followed by energy-releasing relaxation. The result is a nanoflare energy distribution. Furthermore, we produce different distributions by varying the loop aspect ratio, the nature of the path to instability taken by each loop and also the level of radial expansion that may accompany loop relaxation. The heating rate obtained is just sufficient for coronal heating. In addition, we also show that kink instability cannot be associated with a critical magnetic twist value for every point along the instability threshold

Did the London Initiative Zone investment programme affect general practice structure and performance in East London? A time series analysis of cervical screening coverage and asthma prescribing

A programme of incentives was set up in the London Initiative Zones to improve primary care in inner London based on the findings of the Tomlinson Enquiry in 1992. This descriptive study is a 4-y time series analysis of changes in general practice structure in East London as the result of London Initiative Zone investment, and an exploration of the possible effect of investment on practice performance.We used routinely available administrative data for the whole analysis. General practice characteristics and two selected performance indicators: the asthma prophylaxis to bronchodilator ratio and cervical cytology screening rate, for all practices in the East London and the City Health Authority for 4 y, 1993-1996, were used. Both reflect practice efficiency, but relate to different aspects of practice performance. The prescribing indicator is more indicative of the quality of clinical practise, whereas cervical screening coverage relates more to the characteristics of the practice population and to practice organisation. Repeated measures analyses were used to identify trends and to explore the relationship between changes in practice characteristics and performance. Graphical methods were used to compare East London trends with the rest of England.There were significant improvements in practice structure as the consequence of London Initiative Zone investment. There was a positive association with improvements in practice performance, but East London still lagged some way behind national patterns. The findings suggest that while improvements in asthma prescribing follow the national trend, practices have difficulty in achieving and sustaining the 80% target for cervical cytology screening, and that an overall population coverage of 80% may be in doubt.Increased investment in practice staffing may be influential in improving some aspects of performance. However, in common with other inner cities, a greater effort and more innovative strategies may be needed to achieve a standard of performance equal to the best

Fungal entomopathogens: new insights on their ecology

An important mechanism for insect pest control should be the use of fungal entomopathogens. Even though these organisms have been studied for more than 100 y, their effective use in the field remains elusive. Recently, however, it has been discovered that many of these entomopathogenic fungi play additional roles in nature. They are endophytes, antagonists of plant pathogens, associates with the rhizosphere, and possibly even plant growth promoting agents. These findings indicate that the ecological role of these fungi in the environment is not fully understood and limits our ability to employ them successfully for pest management. In this paper, we review the recently discovered roles played by many entomopathogenic fungi and propose new research strategies focused on alternate uses for these fungi. It seems likely that these agents can be used in multiple roles in protecting plants from pests and diseases and at the same time promoting plant growth

Magnetoluminescence

Pulsar Wind Nebulae, Blazars, Gamma Ray Bursts and Magnetars all contain regions where the electromagnetic energy density greatly exceeds the plasma energy density. These sources exhibit dramatic flaring activity where the electromagnetic energy distributed over large volumes, appears to be converted efficiently into high energy particles and gamma-rays. We call this general process magnetoluminescence. Global requirements on the underlying, extreme particle acceleration processes are described and the likely importance of relativistic beaming in enhancing the observed radiation from a flare is emphasized. Recent research on fluid descriptions of unstable electromagnetic configurations are summarized and progress on the associated kinetic simulations that are needed to account for the acceleration and radiation is discussed. Future observational, simulation and experimental opportunities are briefly summarized.Comment: To appear in "Jets and Winds in Pulsar Wind Nebulae, Gamma-ray Bursts and Blazars: Physics of Extreme Energy Release" of the Space Science Reviews serie

Galaxy And Mass Assembly (GAMA): the galaxy stellar mass function to z = 0.1 from the r-band selected equatorial regions

We derive the low-redshift galaxy stellar mass function (GSMF), inclusive of dust corrections, for the equatorial Galaxy And Mass Assembly (GAMA) data set covering 180 deg2. We construct the mass function using a density-corrected maximum volume method, using masses corrected for the impact of optically thick and thin dust. We explore the galactic bivariate brightness plane (M⋆–μ), demonstrating that surface brightness effects do not systematically bias our mass function measurement above 107.5 M⊙. The galaxy distribution in the M–μ plane appears well bounded, indicating that no substantial population of massive but diffuse or highly compact galaxies are systematically missed due to the GAMA selection criteria. The GSMF is fitted with a double Schechter function, with M⋆=1010.78±0.01±0.20M⊙ M⋆=1010.78±0.01±0.20M⊙ , ϕ⋆1=(2.93±0.40)×10−3h370 ϕ1⋆=(2.93±0.40)×10−3h703 Mpc−3, α1 = −0.62 ± 0.03 ± 0.15, ϕ⋆2=(0.63±0.10)×10−3h370 ϕ2⋆=(0.63±0.10)×10−3h703 Mpc−3 and α2 = −1.50 ± 0.01 ± 0.15. We find the equivalent faint end slope as previously estimated using the GAMA-I sample, although we find a higher value of M⋆ M⋆ . Using the full GAMA-II sample, we are able to fit the mass function to masses as low as 107.5  M⊙, and assess limits to 106.5  M⊙. Combining GAMA-II with data from G10-COSMOS, we are able to comment qualitatively on the shape of the GSMF down to masses as low as 106 M⊙. Beyond the well-known upturn seen in the GSMF at 109.5, the distribution appears to maintain a single power-law slope from 109 to 106.5. We calculate the stellar mass density parameter given our best-estimate GSMF, finding Ω⋆=1.66+0.24−0.23±0.97h−170×10−3 Ω⋆=1.66−0.23+0.24±0.97h70−1×10−3 , inclusive of random and systematic uncertainties

Peanut Can Be Used as a Reference Allergen for Hazard Characterization in Food Allergen Risk Management: A Rapid Evidence Assessment and Meta-Analysis

Regional and national legislation mandates the disclosure of “priority” allergens when present as an ingredient in foods, but this does not extend to the unintended presence of allergens due to shared production facilities. This has resulted in a proliferation of precautionary allergen (“may contain”) labels (PAL) that are frequently ignored by food-allergic consumers. Attempts have been made to improve allergen risk management to better inform the use of PAL, but a lack of consensus has led to variety of regulatory approaches and nonuniformity in the use of PAL by food businesses. One potential solution would be to establish internationally agreed “reference doses,” below which no PAL would be needed. However, if reference doses are to be used to inform the need for PAL, then it is essential to characterize the hazard associated with these low-level exposures. For peanut, there are now published data relating to over 3000 double-blind, placebo-controlled challenges in allergic individuals, but a similar level of evidence is lacking for other priority allergens. We present the results of a rapid evidence assessment and meta-analysis for the risk of anaphylaxis to a low-level allergen exposure for priority allergens. On the basis of this analysis, we propose that peanut can and should be considered an exemplar allergen for the hazard characterization at a low-level allergen exposure. Resumen: La legislación regional y nacional exige la divulgación de alérgenos "prioritarios" cuando están presentes como ingrediente en los alimentos, pero esto no se extiende a la presencia involuntaria de alérgenos debido a instalaciones de producción compartidas. Esto ha dado lugar a una proliferación de etiquetas de precaución para alérgenos ("pueden contener") (PAL) que los consumidores alérgicos a los alimentos suelen ignorar. Se han hecho intentos para mejorar la gestión del riesgo de alérgenos para informar mejor el uso de PAL, pero la falta de consenso ha llevado a una variedad de enfoques regulatorios y a la falta de uniformidad en el uso de PAL por parte de las empresas alimentarias. Una posible solución sería establecer “dosis de referencia” acordadas internacionalmente, por debajo de las cuales no se necesitaría PAL. Sin embargo, si se van a utilizar dosis de referencia para informar la necesidad de PAL, entonces es esencial caracterizar el peligro asociado con estas exposiciones de bajo nivel. Para el maní, ahora hay datos publicados relacionados con más de 3000 desafíos doble ciego controlados por placebo en individuos alérgicos, pero falta un nivel similar de evidencia para otros alérgenos prioritarios. Presentamos los resultados de una evaluación rápida de la evidencia y un metanálisis del riesgo deanafilaxia a una exposición a alérgenos de bajo nivel para alérgenos prioritarios. Sobre la base de este análisis, proponemos que el cacahuete puede y debe considerarse un alérgeno ejemplar para la caracterización del peligro en una exposición a un alérgeno de bajo nivel.Instituto de Investigación de Tecnología de AlimentosFil: Turner, Paul J. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Patel, Nandinee. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Ballmer-Weber, Barbara K. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Ballmer-Weber, Barbara K. Clínica de Dermatología y Alergología. Kantonsspital; Suiza.Fil: Baumert, Joe L. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Blom, W. Marty. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Brooke-Taylor, Simon. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Brough, Helen. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Brough, Helen. King's College London. Departamento de Alergia Pediátrica; Reino Unido.Fil: Campbell, Dianne E. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Campbell, Dianne E. Tecnologías DBV. Montrouge; Francia.Fil: Chen, Hongbing. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Chinthrajah, R. Sharon. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Crevel, René W.R. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Dubois, Anthony E.J. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Ebisawa, Motohiro. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Elizur, Arnon. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Elizur, Arnon. Universidad de Tel Aviv. Facultad de Medicina Sackler. Departamento de Pediatría; Israel.Fil: Gerdts, Jennifer D. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Gowland, M. Hazel. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Houben, Geert F. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Hourihane, Jonathan O.B. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Knulst, André C. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: La Vieille, Sébastien. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: López, María Cristina. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Mills, E.N. Clare. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Polenta, Gustavo Alberto. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Investigación Tecnología de Alimentos; Argentina.Fil: Polenta, Gustavo Alberto. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Purington, Natasha. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Said, María. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Sampson, Hugh A. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Sampson, Hugh A. Escuela de Medicina Icahn. División de Alergia e Inmunología Pediátricasen. Nueva York. Estados Unidos de América.Fil: Schnadt, Sabine. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Södergren, Eva. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Södergren, Eva. ThermoFisher Scientific; Suecia.Fil: Taylor, Stephen L. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Remington, Benjamin C. Imperial College London. Instituto Nacional del Corazón y los Pulmones; Reino Unido.Fil: Remington, Benjamin C. Grupo BV. Consultoría Remington; Holanda