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Showing papers by "University of Hertfordshire published in 2010"


Journal ArticleDOI
Matthew Joseph Griffin, Alain Abergel1, A. Abreu, Peter A. R. Ade2  +186 moreInstitutions (27)
TL;DR: The Spectral and Photometric Imaging REceiver (SPIRE) is the Herschel Space Observatory's sub-millimetre camera and spectrometer as discussed by the authors, which is used for image and spectroscopic data acquisition.
Abstract: The Spectral and Photometric Imaging REceiver (SPIRE), is the Herschel Space Observatory`s submillimetre camera and spectrometer It contains a three-band imaging photometer operating at 250, 350 and 500 mu m, and an imaging Fourier-transform spectrometer (FTS) which covers simultaneously its whole operating range of 194-671 mu m (447-1550 GHz) The SPIRE detectors are arrays of feedhorn-coupled bolometers cooled to 03 K The photometer has a field of view of 4' x 8', observed simultaneously in the three spectral bands Its main operating mode is scan-mapping, whereby the field of view is scanned across the sky to achieve full spatial sampling and to cover large areas if desired The spectrometer has an approximately circular field of view with a diameter of 26' The spectral resolution can be adjusted between 12 and 25 GHz by changing the stroke length of the FTS scan mirror Its main operating mode involves a fixed telescope pointing with multiple scans of the FTS mirror to acquire spectral data For extended source measurements, multiple position offsets are implemented by means of an internal beam steering mirror to achieve the desired spatial sampling and by rastering of the telescope pointing to map areas larger than the field of view The SPIRE instrument consists of a cold focal plane unit located inside the Herschel cryostat and warm electronics units, located on the spacecraft Service Module, for instrument control and data handling Science data are transmitted to Earth with no on-board data compression, and processed by automatic pipelines to produce calibrated science products The in-flight performance of the instrument matches or exceeds predictions based on pre-launch testing and modelling: the photometer sensitivity is comparable to or slightly better than estimated pre-launch, and the spectrometer sensitivity is also better by a factor of 15-2

2,425 citations


Journal ArticleDOI
TL;DR: The AUROC analyses indicate that WHtR may be a more useful global clinical screening tool than WC, with a weighted mean boundary value of 0·5, supporting the simple public health message ‘keep your waist circumference to less than half your height’.
Abstract: This systematic review collated seventy-eight studies exploring waist-to-height ratio (WHtR) and waist circumference (WC) or BMI as predictors of diabetes and CVD, published in English between 1950 and 2008. Twenty-two prospective analyses showed that WHtR and WC were significant predictors of these cardiometabolic outcomes more often than BMI, with similar OR, sometimes being significant predictors after adjustment for BMI. Observations from crosssectional analyses, forty-four in adults, thirteen in children, supported these predictions. Receiver operator characteristic (ROC) analysis revealed mean area under ROC (AUROC) values of 0·704, 0·693 and 0·671 for WHtR, WC and BMI, respectively. Mean boundary values for WHtR, covering all cardiometabolic outcomes, from studies in fourteen different countries and including Caucasian, Asian and Central American subjects, were 0·50 for men and 0·50 for women. WHtR and WC are therefore similar predictors of diabetes and CVD, both being stronger than, and independent of, BMI. To make firmer statistical comparison, a meta-analysis is required. The AUROC analyses indicate that WHtR may be a more useful global clinical screening tool than WC, with a weighted mean boundary value of 0·5, supporting the simple public health message ‘keep your waist circumference to less than half your height’. Waist-to-height ratio: Waist circumference: BMI: Central obesity: Abdominal obesity: Obesity

1,054 citations


Journal ArticleDOI
TL;DR: In this article, the authors proposed a method to solve the problem of single-input single-output (SISO) communication in the context of artificial neural networks (ANNs).

927 citations


Journal ArticleDOI
TL;DR: Two different measures of non-markovianity are introduced that exploit the specific traits of quantum correlations and are suitable for opposite experimental contexts when complete tomographic knowledge about the evolution is available and when no information whatsoever is available.
Abstract: We address the problem of quantifying the non-Markovian character of quantum time evolutions of general systems in contact with an environment. We introduce two different measures of non-Markovianity that exploit the specific traits of quantum correlations and are suitable for opposite experimental contexts. When complete tomographic knowledge about the evolution is available, our measure provides a necessary and sufficient condition to quantify strictly the non-Markovianity. In the opposite case, when no information whatsoever is available, we propose a sufficient condition for non-Markovianity. Remarkably, no optimization procedure underlies our derivation, which greatly enhances the practical relevance of the proposed criteria.

835 citations


Journal ArticleDOI
Sergio Molinari1, B. Swinyard, John Bally2, M. J. Barlow3, J.-P. Bernard4, Paul Martin5, Toby J. T. Moore6, Alberto Noriega-Crespo7, Rene Plume8, Leonardo Testi1, Leonardo Testi9, Annie Zavagno10, Alain Abergel11, Babar Ali7, L. D. Anderson10, Ph. André12, J.-P. Baluteau10, Cara Battersby2, M. T. Beltrán1, M. Benedettini1, N. Billot7, J. A. D. L. Blommaert13, Sylvain Bontemps14, Sylvain Bontemps12, F. Boulanger11, Jan Brand1, Christopher M. Brunt15, Michael G. Burton16, Luca Calzoletti, Sean Carey7, Paola Caselli17, Riccardo Cesaroni1, José Cernicharo18, Sukanya Chakrabarti, Antonio Chrysostomou, Martin Cohen, Mathieu Compiegne5, P. de Bernardis19, G. de Gasperis20, A. M. di Giorgio1, Davide Elia1, F. Faustini, Nicolas Flagey7, Yasuo Fukui21, Gary A. Fuller22, K. Ganga23, Pedro García-Lario, Jason Glenn2, Paul F. Goldsmith24, Matthew Joseph Griffin25, Melvin Hoare17, Maohai Huang26, D. Ikhenaode19, C. Joblin4, G. Joncas27, Mika Juvela28, Jason M. Kirk25, Guilaine Lagache11, Jin-Zeng Li26, T. L. Lim, S. D. Lord7, Massimo Marengo29, Douglas J. Marshall4, Silvia Masi19, Fabrizio Massi1, Mikako Matsuura3, Vincent Minier12, Marc-Antoine Miville-Deschenes11, L. Montier4, L. K. Morgan6, Frédérique Motte12, Joseph C. Mottram15, T. G. Müller30, Paolo Natoli20, J. Neves31, Luca Olmi1, Roberta Paladini7, Deborah Paradis7, Harriet Parsons31, Nicolas Peretto12, Nicolas Peretto22, M. R. Pestalozzi1, Stefano Pezzuto1, F. Piacentini19, Lorenzo Piazzo19, D. Polychroni1, M. Pomarès10, Cristina Popescu30, William T. Reach7, Isabelle Ristorcelli4, Jean-François Robitaille27, Thomas P. Robitaille29, J. A. Rodón10, A. Roy5, Pierre Royer13, D. Russeil10, Paolo Saraceno1, Marc Sauvage12, Peter Schilke32, Eugenio Schisano1, Nicola Schneider12, Frederic Schuller, Benjamin L. Schulz7, B. Sibthorpe25, Hazel Smith29, Michael D. Smith33, L. Spinoglio1, Dimitrios Stamatellos25, Francesco Strafella, Guy S. Stringfellow2, E. Sturm30, R. Taylor8, Mark Thompson31, Alessio Traficante20, Richard J. Tuffs30, Grazia Umana1, Luca Valenziano1, R. Vavrek, M. Veneziani19, Serena Viti3, C. Waelkens13, Derek Ward-Thompson25, Glenn J. White34, L. A. Wilcock25, Friedrich Wyrowski, Harold W. Yorke24, Qizhou Zhang29 
TL;DR: In this paper, the first results from the science demonstration phase for the Hi-GAL survey, the Herschel key program that will map the inner Galactic plane of the Milky Way in 5 bands, were presented.
Abstract: We present the first results from the science demonstration phase for the Hi-GAL survey, the Herschel key program that will map the inner Galactic plane of the Milky Way in 5 bands. We outline our data reduction strategy and present some science highlights on the two observed 2° × 2° tiles approximately centered at l = 30° and l = 59°. The two regions are extremely rich in intense and highly structured extended emission which shows a widespread organization in filaments. Source SEDs can be built for hundreds of objects in the two fields, and physical parameters can be extracted, for a good fraction of them where the distance could be estimated. The compact sources (which we will call cores' in the following) are found for the most part to be associated with the filaments, and the relationship to the local beam-averaged column density of the filament itself shows that a core seems to appear when a threshold around AV ~ 1 is exceeded for the regions in the l = 59° field; a AV value between 5 and 10 is found for the l = 30° field, likely due to the relatively higher distances of the sources. This outlines an exciting scenario where diffuse clouds first collapse into filaments, which later fragment to cores where the column density has reached a critical level. In spite of core L/M ratios being well in excess of a few for many sources, we find core surface densities between 0.03 and 0.5 g cm-2. Our results are in good agreement with recent MHD numerical simulations of filaments forming from large-scale converging flows.

752 citations


Journal ArticleDOI
TL;DR: This work provides an operational definition of social interaction and shows that interactive processes are more than a context for social cognition: they can complement and even replace individual mechanisms.

697 citations


Journal ArticleDOI
Stephen Anthony Eales1, Loretta Dunne2, David L. Clements3, Asantha Cooray4, G. de Zotti5, G. de Zotti6, Simon Dye1, Rob Ivison7, Matt J. Jarvis8, Guilaine Lagache9, Guilaine Lagache10, Steve Maddox2, Mattia Negrello11, Steve Serjeant11, Mark Thompson8, E. van Kampen12, Alexandre Amblard4, Paola Andreani12, Maarten Baes13, Alexandre Beelen10, Alexandre Beelen9, George J. Bendo3, Dominic J. Benford12, Dominic J. Benford14, Frank Bertoldi13, Frank Bertoldi15, James J. Bock16, D. G. Bonfield8, Alessandro Boselli17, C. Bridge10, V. Buat17, Denis Burgarella17, Raymond G. Carlberg18, Antonio Cava, Pierre Chanial3, S. Charlot19, N. Christopher20, Peter Coles1, Luca Cortese1, Aliakbar Dariush1, E. da Cunha21, Gavin Dalton20, Gavin Dalton22, Luigi Danese23, Helmut Dannerbauer23, Simon P. Driver, James Dunlop7, Lulu Fan18, Duncan Farrah18, David T. Frayer16, Carlos S. Frenk24, James E. Geach24, Jonathan P. Gardner14, Haley Louise Gomez1, J. González-Nuevo18, Eduardo Gonzalez-Solares25, Matthew Joseph Griffin1, Martin J. Hardcastle8, Evanthia Hatziminaoglou12, D. Herranz26, David H. Hughes, Edo Ibar7, Woong-Seob Jeong27, Cedric G. Lacey24, Andrea Lapi28, Andy Lawrence7, Myung Gyoon Lee29, Lerothodi Leonard Leeuw28, Jochen Liske12, M. López-Caniego23, Th. Müller23, Kirpal Nandra3, P. Panuzzo30, Andreas Papageorgiou1, G. Patanchon30, John A. Peacock7, C. P. Pearson22, Steven Phillipps, Michael Pohlen1, Cristina Popescu31, Steve Rawlings20, E. E. Rigby2, M. Rigopoulou20, Aaron S. G. Robotham32, Giulia Rodighiero6, Anne E. Sansom31, Benjamin L. Schulz, Douglas Scott33, D. J. B. Smith2, B. Sibthorpe7, Ian Smail24, Jamie Stevens8, William J. Sutherland34, Tsutomu T. Takeuchi35, Jonathan Tedds36, P. Temi37, Richard J. Tuffs23, Markos Trichas3, Mattia Vaccari6, Ivan Valtchanov38, P. van der Werf39, Aprajita Verma20, J. Vieria39, Catherine Vlahakis39, Glenn J. White11, Glenn J. White22 
TL;DR: The Herschel ATLAS project as discussed by the authors is the largest open-time key project that will be carried out on the Herschel Space Observatory, and it will survey 570 deg2 of the extragalactic sky, 4 times larger than all the other Herschel extragala surveys combined, in five far-infrared and submillimeter bands.
Abstract: The Herschel ATLAS is the largest open-time key project that will be carried out on the Herschel Space Observatory. It will survey 570 deg2 of the extragalactic sky, 4 times larger than all the other Herschel extragalactic surveys combined, in five far-infrared and submillimeter bands. We describe the survey, the complementary multiwavelength data sets that will be combined with the Herschel data, and the six major science programs we are undertaking. Using new models based on a previous submillimeter survey of galaxies, we present predictions of the properties of the ATLAS sources in other wave bands.

610 citations


Journal ArticleDOI
TL;DR: It is suggested that impulsivity and compulsivity each seem to be multidimensional, and Serotonin and dopamine interact across these circuits to modulate aspects of both impulsive and compulsive responding and as yet unidentified brain-based systems may also have important functions.

595 citations


Journal ArticleDOI
TL;DR: In this article, the relationship between atomic hydrogen (Hi) and far-ultraviolet (FUV) emission outside the optical radius (r25 )i n 17 spiral and 5 dwarf galaxies was studied.
Abstract: We combine data from The Hi Nearby Galaxy Survey and the GALEX Nearby Galaxy Survey to study the relationship between atomic hydrogen (Hi) and far-ultraviolet (FUV) emission outside the optical radius (r25 )i n 17 spiral and 5 dwarf galaxies. In this regime, Hi is likely to represent most of the interstellar medium (ISM) and FUV emission to trace recent star formation with little bias due to extinction, so that the two quantities closely trace the underlying relationship between gas and star formation rate (SFR). The azimuthally averaged Hi and FUV intensities both decline with increasing radius in this regime, with the scale length of the FUV profile typically half that of the Hi profile. Despite the mismatch in profiles, there is a significant spatial correlation (at 15 �� resolution) between local FUV and Hi intensities; near r25 this correlation is quite strong, in fact stronger than anywhere inside r25 (where Hi is not a good tracer for the bulk of the ISM), and shows a decline toward larger radii. The star formation efficiency (SFE)—defined as the ratio of FUV/Hi and thus the inverse of the gas depletion time—decreases with galactocentric radius across the outer disks, though much shallower than across the optical disks. On average, we find the gas depletion times to be well above a Hubble time (∼10 11 yr). We observe a clear relationship between FUV/Hi and Hi column in the outer disks, with the SFE increasing with increasing Hi column. Despite observing systematic variations in FUV/Hi, we find no clear evidence for stepfunction-type star formation thresholds, though we emphasize that it may not be realistic to expect them. When compared with results from insider25, we find outer disk star formation to be distinct in several ways: it is extremely inefficient (depletion times of many Hubble times which are also long compared to either the free fall or orbital timescale) with column densities and SFRs lower than found anywhere inside the optical disks. It appears that the Hi column is one of the key environmental factors—perhaps the key factor—in setting the SFR in outer galaxy disks.

450 citations


Journal ArticleDOI
TL;DR: In this paper, the effect of environment on the evolution of early-type galaxies as imprinted in the fossil record was analyzed by analysing the stellar population properti es of 3,360 galaxies morphologically selected by visual inspection from the Sloan Digital Sky Survey in a narrow redshift range (0.05 6 z 6 0.06).
Abstract: The environment is known to affect the formation and evolution of galaxies considerably best visible through the well-known morphology-density relationship. It is less clear, though, whether the environment is equally important at a given galaxy morphology. In this paper we study the effect of environment on the evolution of early-type galaxies as imprinted in the fossil record by analysing the stellar population properti es of 3,360 galaxies morphologically selected by visual inspection from the Sloan Digital Sky Survey in a narrow redshift range (0.05 6 z 6 0.06). The morphological selection algorithm is critical as it d oes not bias against recent star formation. We find that the distribution of ages is bimodal with a strong peak at old ages and a secondary peak at young ages around � 2.5 Gyr containing about 10 per cent of the objects. This is analogue to ’red sequence’ and ’blue cloud’ identified in galaxy populations usually containing both early and late type galaxies. The fraction of the young, rejuvenated galaxies increases with both decreasing galaxy mass and decreasing environmental density up to about 45 per cent, which implies that the impact of environment increases with decreasing galaxy mass. The rejuvenated galaxies have lower �/Fe ratios than the average and most of them show signs of ongoing star formation through their emission line spectra. All objects that host AGN in their centres with out star formation are part of the red sequence population. We confirm and statistically stren gthen earlier results that luminosity weighted ages, metallicities, and �/Fe element ratios of the red sequence population correlate well with velocity dispersion and galaxy mass. Most interestingly, however, these scaling relations are not sensitive to environmental densities and are only driven by galaxy mass. We infer that early-type galaxy formation has undergone a phase transition a few billion years ago aroundz � 0.2. A self-regulated formation phase without environmental dependence has recently been superseded by a rejuvenation phase, in which the environment plays a decisive role possibly through galaxy mergers and interactions.

448 citations


Journal ArticleDOI
Mattia Negrello1, Rosalind Hopwood1, G. de Zotti, Asantha Cooray2, Aprajita Verma3, J. J. Bock4, J. J. Bock5, David T. Frayer6, Mark Gurwell7, Alain Omont8, R. Neri, Helmut Dannerbauer9, Lerothodi Leonard Leeuw10, Lerothodi Leonard Leeuw11, Elizabeth J. Barton2, Jeff Cooke2, Jeff Cooke4, S. Kim2, E. da Cunha12, Giulia Rodighiero13, Peter Timothy Cox, D. G. Bonfield14, Matt J. Jarvis14, Steve Serjeant1, Rob Ivison15, Simon Dye16, Itziar Aretxaga17, David H. Hughes17, Edo Ibar, Frank Bertoldi18, Ivan Valtchanov19, Stephen Anthony Eales16, Loretta Dunne20, Simon P. Driver21, Robbie Richard Auld16, S. Buttiglione, Antonio Cava22, Antonio Cava23, C. A. Grady24, David L. Clements25, Aliakbar Dariush16, Jacopo Fritz26, Denis Hill21, J. B. Hornbeck27, Lee S. Kelvin21, Guilaine Lagache28, M. López-Caniego23, J. González-Nuevo, Steve Maddox20, Enzo Pascale16, Michael Pohlen16, E. E. Rigby20, Aaron S. G. Robotham21, Chris Simpson29, Daniel J. Smith20, P. Temi30, Mark Thompson14, B. E. Woodgate24, Donald G. York31, James E. Aguirre32, Alexandre Beelen28, Andrew Blain4, Andrew J. Baker33, Mark Birkinshaw34, R. Blundell7, Charles M. Bradford4, Charles M. Bradford5, Denis Burgarella35, Luigi Danese, James Dunlop, S. Fleuren36, Jason Glenn37, Andrew I. Harris38, Julia Kamenetzky37, Roxana Lupu32, Ronald J. Maddalena6, Barry F. Madore39, P. R. Maloney37, Hideo Matsuhara40, M. J. Michaowski15, Eric J. Murphy, B. J. Naylor5, Hien Nguyen5, Cristina Popescu41, Steve Rawlings3, Dimitra Rigopoulou3, Dimitra Rigopoulou42, Douglas Scott43, Kimberly S. Scott32, Mark Seibert39, Ian Smail44, Richard J. Tuffs45, Joaquin Vieira4, P. van der Werf46, P. van der Werf15, Jonas Zmuidzinas4, Jonas Zmuidzinas5 
05 Nov 2010
TL;DR: Early data from the Herschel Astrophysical Terahertz Large Area Survey are used to demonstrate that wide-area submillimeter surveys can simply and easily detect strong gravitational lensing events, with close to 100% efficiency.
Abstract: Gravitational lensing is a powerful astrophysical and cosmological probe and is particularly valuable at submillimeter wavelengths for the study of the statistical and individual properties of dusty star-forming galaxies. However, the identification of gravitational lenses is often time-intensive, involving the sifting of large volumes of imaging or spectroscopic data to find few candidates. We used early data from the Herschel Astrophysical Terahertz Large Area Survey to demonstrate that wide-area submillimeter surveys can simply and easily detect strong gravitational lensing events, with close to 100% efficiency.

Journal ArticleDOI
TL;DR: It is demonstrated that extending valganciclovir prophylaxis (900 mg once daily) to 200 days significantly reduces the incidence of CMV disease and viremia through to 12 months compared with 100 days’ prophYLaxis, without significant additional safety concerns associated with longer treatment.

Journal ArticleDOI
Markus Ackermann1, Katsuaki Asano2, W. B. Atwood3, Magnus Axelsson4  +216 moreInstitutions (44)
TL;DR: In this article, the authors present detailed observations of the bright short-hard gamma-ray burst GRB 090510 made with the Gammaray Burst Monitor (GBM) and Large Area Telescope (LAT) on board the Fermi observatory.
Abstract: We present detailed observations of the bright short-hard gamma-ray burst GRB 090510 made with the Gammaray Burst Monitor (GBM) and Large Area Telescope (LAT) on board the Fermi observatory. GRB 090510 is the first burst detected by the LAT that shows strong evidence for a deviation from a Band spectral fitting function during the prompt emission phase. The time-integrated spectrum is fit by the sum of a Band function with E-peak = 3.9 +/- 0.3 MeV, which is the highest yet measured, and a hard power-law component with photon index -1.62 +/- 0.03 that dominates the emission below approximate to 20 keV and above approximate to 100 MeV. The onset of the high-energy spectral component appears to be delayed by similar to 0.1 s with respect to the onset of a component well fit with a single Band function. A faint GBM pulse and a LAT photon are detected 0.5 s before the main pulse. During the prompt phase, the LAT detected a photon with energy 30.5(-2.6)(+5.8) GeV, the highest ever measured from a short GRB. Observation of this photon sets a minimum bulk outflow Lorentz factor, Gamma greater than or similar to 1200, using simple.. opacity arguments for this GRB at redshift z = 0.903 and a variability timescale on the order of tens of ms for the approximate to 100 keV-few MeV flux. Stricter high confidence estimates imply Gamma greater than or similar to 1000 and still require that the outflows powering short GRBs are at least as highly relativistic as those of long-duration GRBs. Implications of the temporal behavior and power-law shape of the additional component on synchrotron/synchrotron self-Compton, external-shock synchrotron, and hadronic models are considered.

Journal ArticleDOI
TL;DR: This article re-examines and challenges some basic assumptions in the nutritional antioxidant field and suggests that pro-oxidants can be better for you in some circumstances.

Journal ArticleDOI
TL;DR: In this paper, a stellar population analysis of the absorption line strength maps for 48 early-type galaxies from the SAURON sample is presented, where the authors estimate the simple stellar population-equivalent age, metallicity and abundance ratio [alpha/Fe] over a two-dimensional field extending up to approximately one effective radius.
Abstract: We present a stellar population analysis of the absorption line strength maps for 48 early-type galaxies from the SAURON sample. Using the line strength index maps of H beta, Fe5015 and Mgb, measured in the Lick/IDS system and spatially binned to a constant signal-to-noise ratio, together with predictions from up-to-date stellar population models, we estimate the simple stellar population-equivalent (SSP-equivalent) age, metallicity and abundance ratio [alpha/Fe] over a two-dimensional field extending up to approximately one effective radius. A discussion of calibrations and differences between model predictions is given. Maps of SSP-equivalent age, metallicity and abundance ratio [alpha/Fe] are presented for each galaxy. We find a large range of SSP-equivalent ages in our sample, of which similar to 40 per cent of the galaxies show signs of a contribution from a young stellar population. The most extreme cases of post-starburst galaxies, with SSP-equivalent ages of The flattened components with disc-like kinematics previously identified in all fast rotators are shown to be connected to regions of distinct stellar populations. These range from the young, still star-forming circumnuclear discs and rings with increased metallicity preferentially found in intermediate-mass fast rotators, to apparently old structures with extended disc-like kinematics, which are observed to have an increased metallicity and mildly depressed [alpha/Fe] ratio compared to the main body of the galaxy. The slow rotators, often harbouring kinematically decoupled components (KDC) in their central regions, generally show no stellar population signatures over and above the well-known metallicity gradients in early-type galaxies and are largely consistent with old (>= 10 Gyr) stellar populations. Using radially averaged stellar population gradients we find in agreement with Spolaor et al. a mass-metallicity gradient relation where low-mass fast rotators form a sequence of increasing metallicity gradient with increasing mass. For more massive systems (above similar to 3.5 x 10(10) M-circle dot) there is an overall downturn such that metallicity gradients become shallower with increased scatter at a given mass leading to the most massive systems being slow rotators with relatively shallow metallicity gradients. The observed shallower metallicity gradients and increased scatter could be a consequence of the competition between different star formation and assembly scenarios following a general trend of diminishing gas fractions and more equal-mass mergers with increasing mass, leading to the most massive systems being devoid of ordered motion and signs of recent star formation.

Journal ArticleDOI
TL;DR: In this article, the authors provide physically intuitive mechanisms for the effect of noise on excitation energy transfer (EET) in networks and demonstrate explicitly how noise alters the pathways of energy transfer across the complex, suppressing ineffective pathways and facilitating direct ones to the reaction centre.
Abstract: We provide physically intuitive mechanisms for the effect of noise on excitation energy transfer (EET) in networks. Using these mechanisms of dephasing-assisted transport (DAT) in a hybrid basis of both excitons and sites, we develop a detailed picture of how noise enables energy transfer with efficiencies well above 90% across the Fenna–Matthew–Olson (FMO) complex, a type of light-harvesting molecule. We demonstrate explicitly how noise alters the pathways of energy transfer across the complex, suppressing ineffective pathways and facilitating direct ones to the reaction centre. We explain that the fundamental mechanisms underpinning DAT are expected to be robust with respect to the considered noise model but show that the specific details of the exciton–phonon coupling, which remain largely unknown in these type of complexes, and in particular the impact of non-Markovian effects, result in variations of dynamical features that should be amenable to experimental verification with current or planned technology. A detailed understanding of DAT in natural compounds could open up a new paradigm of 'noise-engineering' by which EET can be optimized in artificial light-harvesting structures.

Journal ArticleDOI
TL;DR: In this article, the sensitivity of SPIRE photometers on the Herschel Space Observatory was investigated and the authors measured the confusion noise from observations taken during the science demonstration phase of the HS survey.
Abstract: We report on the sensitivity of SPIRE photometers on the Herschel Space Observatory. Specifically, we measure the confusion noise from observations taken during the science demonstration phase of the Herschel Multi-tiered Extragalactic Survey. Confusion noise is defined to be the spatial variation of the sky intensity in the limit of infinite integration time, and is found to be consistent among the different fields in our survey at the level of 5.8, 6.3 and 6.8 mJy/beam at 250, 350 and 500 μm, respectively. These results, together with the measured instrument noise, may be used to estimate the integration time required for confusion limited maps, and provide a noise estimate for maps obtained by SPIRE.

Journal ArticleDOI
TL;DR: In this article, the authors studied the incidence, morphology and kinematics of the ionised gas in early-type galaxies and addressed the question of what is powering the observed nebular.
Abstract: Following our study on the incidence, morphology and kinematics of the ionised gas in early-type galaxies we now address the question of what is powering the observed nebular

Journal ArticleDOI
TL;DR: The first indications of a class of long GRBs are presented, which form a bridge between the typical high-luminosity, high-redshift events and nearby low- luminosity events (which are also associated with spectroscopic supernovae) in terms of energetics and observed redshift distribution, indicating a continuous distribution overall.
Abstract: We have gathered optical photometry data from the literature on a large sample of Swift-era gamma-ray burst (GRB) afterglows including GRBs up to 2009 September, for a total of 76 GRBs, and present an additional three pre-Swift GRBs not included in an earlier sample. Furthermore, we publish 840 additional new photometry data points on a total of 42 GRB afterglows, including large data sets for GRBs 050319, 050408, 050802, 050820A, 050922C, 060418, 080413A, and 080810. We analyzed the light curves of all GRBs in the sample and derived spectral energy distributions for the sample with the best data quality, allowing us to estimate the host-galaxy extinction. We transformed the afterglow light curves into an extinction-corrected z = 1 system and compared their luminosities with a sample of pre-Swift afterglows. The results of a former study, which showed that GRB afterglows clustered and exhibited a bimodal distribution in luminosity space, are weakened by the larger sample. We found that the luminosity distribution of the two afterglow samples (Swift-era and pre-Swift) is very similar, and that a subsample for which we were not able to estimate the extinction, which is fainter than the main sample, can be explained by assuming a moderate amount of line-of-sight host extinction. We derived bolometric isotropic energies for all GRBs in our sample, and found only a tentative correlation between the prompt energy release and the optical afterglow luminosity at 1 day after the GRB in the z = 1 system. A comparative study of the optical luminosities of GRB afterglows with echelle spectra (which show a high number of foreground absorbing systems) and those without, reveals no indication that the former are statistically significantly more luminous. Furthermore, we propose the existence of an upper ceiling on afterglow luminosities and study the luminosity distribution at early times, which was not accessible before the advent of the Swift satellite. Most GRBs feature afterglows that are dominated by the forward shock from early times on. Finally, we present the first indications of a class of long GRBs, which form a bridge between the typical high-luminosity, high-redshift events and nearby low-luminosity events (which are also associated with spectroscopic supernovae) in terms of energetics and observed redshift distribution, indicating a continuous distribution overall.

Journal ArticleDOI
01 Jul 2010-Steroids
TL;DR: In this article, the authors describe procedures, performance characteristics and limitations of methods available for the measurement of 25-hydroxyvitamin (25OHD) since the year 2000.

Journal ArticleDOI
TL;DR: CBT is no better than non-specific control interventions in the treatment of schizophrenia and does not reduce relapse rates, but it is effective in major depression but the size of the effect is small in treatment studies.
Abstract: Original article can be found at : http://journals.cambridge.org/ Copyright Cambridge University Press

Journal ArticleDOI
TL;DR: It is essential that all new cell cultures entering a laboratory and all cell banks are tested for the presence of Mycoplasma, and two techniques be used, selected from a PCR-based method, indirect staining and an agar and broth culture.
Abstract: Mycoplasma is a prokaryotic organism that is a frequent and occult contaminant of cell cultures. This organism can modify many aspects of cell physiology, rendering experiments that are conducted with contaminated cells worthless. Because of their small size, Mycoplasmas can pass through filters used to prevent bacterial and fungal contamination and potentially spread to all the cultures in a laboratory. It is essential that all new cell cultures entering a laboratory and all cell banks are tested for the presence of Mycoplasma. It is recommended that two techniques be used, selected from a PCR-based method, indirect staining and an agar and broth culture. This protocol describes these three tests for detecting Mycoplasma, which take from 1 d to 3-4 weeks, and such tests should be an obligatory component of quality control in every tissue culture laboratory.

Journal ArticleDOI
TL;DR: Intergenerational influences on parental health beliefs and knowledge suggest that health promotion strategies may be more effective if directed at the wider family, rather than parents alone.
Abstract: The definitive version can be found at: http://www3.interscience.wiley.com/ Copyright International Association for the Study of Obesity

Journal ArticleDOI
TL;DR: The preliminary recommendation is that an OC‐spectrum grouping of disorders be included in DSM‐V and consideration be given to including this group of disorders within a larger supraordinate category of “Anxiety and Obsessive–Compulsive Spectrum Disorders.”
Abstract: The obsessive-compulsive (OC) spectrum has been discussed in the literature for two decades. Proponents of this concept propose that certain disorders characterized by repetitive thoughts and/or behaviors are related to obsessive-compulsive disorder (OCD), and suggest that such disorders be grouped together in the same category (i.e. grouping, or "chapter") in DSM. This article addresses this topic and presents options and preliminary recommendations to be considered for DSM-V. The article builds upon and extends prior reviews of this topic that were prepared for and discussed at a DSM-V Research Planning Conference on Obsessive-Compulsive Spectrum Disorders held in 2006. Our preliminary recommendation is that an OC-spectrum grouping of disorders be included in DSM-V. Furthermore, we preliminarily recommend that consideration be given to including this group of disorders within a larger supraordinate category of "Anxiety and Obsessive-Compulsive Spectrum Disorders." These preliminary recommendations must be evaluated in light of recommendations for, and constraints upon, the overall structure of DSM-V.

Journal ArticleDOI
A. A. Abdo1, A. A. Abdo2, Markus Ackermann3, Marco Ajello3  +200 moreInstitutions (30)
07 May 2010-Science
TL;DR: These measurements provide gamma-ray constraints on the magnetic field and particle energy content in radio galaxy lobes, as well as a promising method to probe the cosmic relic photon fields.
Abstract: The Fermi Gamma-ray Space Telescope has detected the gamma-ray glow emanating from the giant radio lobes of the radio galaxy Centaurus A. The resolved gamma-ray image shows the lobes clearly separated from the central active source. In contrast to all other active galaxies detected so far in high-energy gamma-rays, the lobe flux constitutes a considerable portion (greater than one-half) of the total source emission. The gamma-ray emission from the lobes is interpreted as inverse Compton-scattered relic radiation from the cosmic microwave background, with additional contribution at higher energies from the infrared-to-optical extragalactic background light. These measurements provide gamma-ray constraints on the magnetic field and particle energy content in radio galaxy lobes, as well as a promising method to probe the cosmic relic photon fields.

Journal ArticleDOI
TL;DR: The PHoto-z Accuracy Testing Program (PHAT) as mentioned in this paper is an international initiative to test and compare different methods of photo-z estimation, and the test data sets are publicly available and can be used to compare new, upcoming methods to established ones and help in guiding future photoz method development.
Abstract: Context. Photometric redshifts (photo-z's) have become an essential tool in extragalactic astronomy. Many current and upcoming observing programmes require great accuracy of photo-z's to reach their scientific goals. Aims. Here we introduce PHAT, the PHoto-z Accuracy Testing programme, an international initiative to test and compare different methods of photo-z estimation. Methods. Two different test environments are set up, one (PHAT0) based on simulations to test the basic functionality of the different photo-z codes, and another one (PHAT1) based on data from the GOODS survey including 18-band photometry and similar to 2000 spectroscopic redshifts. Results. The accuracy of the different methods is expressed and ranked by the global photo-z bias, scatter, and outlier rates. While most methods agree very well on PHAT0 there are differences in the handling of the Lyman-alpha forest for higher redshifts. Furthermore, different methods produce photo-z scatters that can differ by up to a factor of two even in this idealised case. A larger spread in accuracy is found for PHAT1. Few methods benefit from the addition of mid-IR photometry. The accuracy of the other methods is unaffected or suffers when IRAC data are included. Remaining biases and systematic effects can be explained by shortcomings in the different template sets (especially in the mid-IR) and the use of priors on the one hand and an insufficient training set on the other hand. Some strategies to overcome these problems are identified by comparing the methods in detail. Scatters of 4-8% in Delta z/(1 + z) were obtained, consistent with other studies. However, somewhat larger outlier rates (\textgreater 7.5% with Delta z/(1 + z) \textgreater 0.15; \textgreater 4.5% after cleaning) are found for all codes that can only partly be explained by AGN or issues in the photometry or the spec-z catalogue. Some outliers were probably missed in comparisons of photo-z's to other, less complete spectroscopic surveys in the past. There is a general trend that empirical codes produce smaller biases than template-based codes. Conclusions. The systematic, quantitative comparison of different photo-z codes presented here is a snapshot of the current state-of-the-art of photo-z estimation and sets a standard for the assessment of photo-z accuracy in the future. The rather large outlier rates reported here for PHAT1 on real data should be investigated further since they are most probably also present (and possibly hidden) in many other studies. The test data sets are publicly available and can be used to compare new, upcoming methods to established ones and help in guiding future photo-z method development.

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TL;DR: In this article, a coherent database on interstellar dust emission from diffuse clouds to the sites of star formation has been built to study the far-infrared/submillimeter emission of the PDRs and their fainter surrounding regions.
Abstract: Context In photodissociation regions (PDRs), the physical conditions and the excitation evolve on short spatial scales as a function of depth within the cloud, providing a unique opportunity to study how the dust and gas populations evolve with the excitation and physical conditions The mapping of the PDRs in NGC 7023 performed during the science demonstration phase of Herschel is part of the “Evolution of interstellar dust” key program The goal of this project is to build a coherent database on interstellar dust emission from diffuse clouds to the sites of star formation Aims We study the far-infrared/submillimeter emission of the PDRs and their fainter surrounding regions We combine the Herschel and Spitzer maps to derive at each position the full emission spectrum of all dust components, which we compare to dust and radiative transfer models in order to learn about the spatial variations in both the excitation conditions and the dust properties Methods We adjust the emission spectra derived from PACS and SPIRE maps using modified black bodies to derive the temperature and the emissivity index β of the dust in thermal equilibrium with the radiation field We present a first modeling of the NGC 7023-E PDR with standard dust properties and abundances Results At the peak positions, a value of β equal to 2 is compatible with the data The detected spectra and the spatial structures are strongly influenced by radiative transfer effects We are able to reproduce the spectra at the peak positions deduced from Herschel maps and emitted by dust particles at thermal equilibrium, and also the evolution of the spatial structures observed from the near infrared to the submillimeter On the other hand, the emission of the stochastically heated smaller particles is overestimated by a factor ~2

Journal ArticleDOI
TL;DR: RA-ILD is an important and early feature of RA, related to disease activity and has a poor prognosis, and further studies are required to determine whether screening for pulmonary disease would identify patients at an earlier stage.
Abstract: Objectives Pulmonary complications of RA are well described. Although some are benign, interstitial lung disease (ILD) has a poor prognosis. Few RA inception cohorts have reported the natural history of ILD related to RA (RA-ILD). We examine its incidence, outcome and prognostic indicators. Methods Extra-articular features and comorbidity have been recorded yearly in a well-established inception cohort of RA with a 20-year follow-up. Standard clinical, laboratory and radiological measures of RA were recorded at baseline and yearly. Details of deaths were provided by a national central register. Results Out of 1460 patients, 52 developed RA-ILD, half either at baseline or within 3 years of onset. The annualized incidence was 4.1/1000 (95% CI 3.0, 5.4) and the 15-year cumulative incidence 62.9/1000 (95% CI 43.0, 91.7). Incidence of RA-ILD was associated with older age, raised baseline ESR and HAQ. Evidence to implicate any drug effect (e.g. MTX) was lacking. Of these patients, 39 died, attributed to RA-ILD in 28. Median survival following diagnosis of RA-ILD was 3 years. Conclusions RA-ILD is an important and early feature of RA. It is related to disease activity and has a poor prognosis. Further studies are required to determine whether screening for pulmonary disease would identify these patients at an earlier stage.

Journal ArticleDOI
TL;DR: TaqMan™ quantitative polymerase chain reaction (PCR) analysis of SGLT2 and other sodium/glucose transporter genes on RNAs from 72 normal tissues from three different individuals consistently observe that S GLT2 is highly kidney specific while SGLSGLT5 ishighly kidney abundant.
Abstract: SGLT2 (for “Sodium GLucose coTransporter” protein 2) is the major protein responsible for glucose reabsorption in the kidney and its inhibition has been the focus of drug discovery efforts to treat type 2 diabetes. In order to better clarify the human tissue distribution of expression of SGLT2 and related members of this cotransporter class, we performed TaqMan™ (Applied Biosystems, Foster City, CA, USA) quantitative polymerase chain reaction (PCR) analysis of SGLT2 and other sodium/glucose transporter genes on RNAs from 72 normal tissues from three different individuals. We consistently observe that SGLT2 is highly kidney specific while SGLT5 is highly kidney abundant; SGLT1, sodium-dependent amino acid transporter (SAAT1), and SGLT4 are highly abundant in small intestine and skeletal muscle; SGLT6 is expressed in the central nervous system; and sodium myoinositol cotransporter is ubiquitously expressed across all human tissues.

Journal ArticleDOI
D. Elbaz1, Ho Seong Hwang1, Benjamin Magnelli2, Emanuele Daddi1, Herve Aussel1, Bruno Altieri3, Alexandre Amblard4, Paola Andreani5, V. Arumugam6, Robbie Richard Auld7, Tom Babbedge8, S. Berta2, Andrew Blain9, James J. Bock9, James J. Bock10, Ángel Bongiovanni11, Alessandro Boselli12, V. Buat12, Denis Burgarella12, N. Castro-Rodriguez11, Antonio Cava11, J. Cepa11, Pierre Chanial8, Ranga-Ram Chary9, Andrea Cimatti13, David L. Clements8, A. Conley14, L. Conversi3, Asantha Cooray9, Asantha Cooray4, Mark Dickinson, H. Dominguez5, Charles D. Dowell10, Charles D. Dowell9, James Dunlop6, Eli Dwek15, Stephen Anthony Eales7, Duncan Farrah16, N. M. Förster Schreiber2, M. Fox8, Alberto Franceschini17, Walter Kieran Gear7, Reinhard Genzel2, Jason Glenn14, Matthew Joseph Griffin7, Carlotta Gruppioni5, Mark Halpern18, Evanthia Hatziminaoglou, Edo Ibar19, Kate Gudrun Isaak7, Rob Ivison19, Rob Ivison6, Guilaine Lagache20, D. Le Borgne21, E. Le Floc'h1, L. R. Levenson10, L. R. Levenson9, Nanyao Y. Lu9, Dieter Lutz2, Suzanne C. Madden1, Bruno Maffei22, Georgios E. Magdis1, G. Mainetti17, Roberto Maiolino5, Lucia Marchetti17, A. M. J. Mortier8, Hien Nguyen9, Hien Nguyen10, Raanan Nordon2, B. O'Halloran8, K. Okumura1, Seb Oliver16, Alain Omont21, M. J. Page23, P. Panuzzo1, Andreas Papageorgiou7, Chris Pearson24, Chris Pearson25, I. Perez Fournon11, A. M. Pérez García11, Albrecht Poglitsch2, Michael Pohlen7, P. Popesso2, Francesca Pozzi5, Jonathan Rawlings23, Dimitra Rigopoulou25, Dimitra Rigopoulou26, L. Riguccini1, D. Rizzo8, Giulia Rodighiero17, Isaac Roseboom16, Michael Rowan-Robinson8, Amélie Saintonge2, M. Sanchez Portal3, P. Santini5, Marc Sauvage1, Benjamin L. Schulz9, Douglas Scott18, Nick Seymour23, Lijing Shao2, D. L. Shupe9, A. J. Smith16, Jamie Stevens27, E. Sturm2, M. Symeonidis23, Linda J. Tacconi2, Markos Trichas8, K. E. Tugwell23, Mattia Vaccari17, Ivan Valtchanov3, Joaquin Vieira9, L. Vigroux21, Lifan Wang16, Robyn L. Ward16, G. Wright19, C. K. Xu9, Michael Zemcov9, Michael Zemcov10 
TL;DR: In this paper, the spectral energy distribution and dust temperature of galaxies have strongly evolved over the last 80% of the age of the Universe, and possible consequences for the determination of star-formation rates (SFR) and any evidence for a major change in their starformation properties.
Abstract: The Herschel Space Observatory enables us to accurately measure the bolometric output of starburst galaxies and active galactic nuclei (AGN) by directly sampling the peak of their far-infrared (IR) emission. Here we examine whether the spectral energy distribution (SED) and dust temperature of galaxies have strongly evolved over the last 80% of the age of the Universe. We discuss possible consequences for the determination of star-formation rates (SFR) and any evidence for a major change in their star-formation properties. We use Herschel deep extragalactic surveys from 100 to 500 μm to compute total IR luminosities in galaxies down to the faintest levels, using PACS and SPIRE in the GOODS-North field (PEP and HerMES key programs). An extension to fainter luminosities is done by stacking images on 24 μm prior positions. We show that measurements in the SPIRE bands can be used below the statistical confusion limit if information at higher spatial resolution is used, e.g. at 24 μm, to identify “isolated” galaxies whose flux is not boosted by bright neighbors. Below z ~ 1.5, mid-IR extrapolations are correct for star-forming galaxies with a dispersion of only 40% (0.15 dex), therefore similar to z ~ 0 galaxies, over three decades in luminosity below the regime of ultra-luminous IR galaxies (ULIRGs, LIR ≥ 1012 ). This narrow distribution is puzzling when considering the range of physical processes that could have affected the SED of these galaxies. Extrapolations from only one of the 160 μm, 250 μm or 350 μm bands alone tend to overestimate the total IR luminosity. This may be explained by the lack of far-IR constraints around and above ~150 μm (rest-frame) before Herschel on those templates. We also note that the dust temperature of luminous IR galaxies (LIRGs, LIR ≥ 1011 ) around z ~ 1 is mildly colder by 10–15% than their local analogs and up to 20% for ULIRGs at z ~ 1.6 (using a single modified blackbody-fit to the peak far-IR emission with an emissivity index of β = 1.5). Above z = 1.5, distant galaxies are found to exhibit a substantially larger mid- over far-IR ratio, which could either result from stronger broad emission lines or warm dust continuum heated by a hidden AGN. Two thirds of the AGNs identified in the field with a measured redshift exhibit the same behavior as purely star-forming galaxies. Hence a large fraction of AGNs harbor coeval star formation at very high SFR and in conditions similar to purely star-forming galaxies.