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We perform cosmological zoom-in simulations of 19 relaxed cluster-mass haloes with the inclusion of adiabatic gas in the cold dark matter (CDM) and self-interacting dark matter (SIDM) models. These clusters are selected as dynamically relaxed clusters from a parent simulation with |$M_{\rm 200} \simeq (1\!-\!3)\times 10^{15}{\, \rm M_\odot }$|⁠. Both the dark matter and the intracluster gas distributions in SIDM appear more spherical than their CDM counterparts. Mock X-ray images are generated based on the simulations and are compared to the real X-ray images of 84 relaxed clusters selected from the Chandra and ROSAT archives. We perform ellipse fitting for the isophotes of mock and real X-ray images and obtain the ellipticities at cluster-centric radii of |$r\simeq 0.1\!-\!0.2R_{\rm 200}$|⁠. The X-ray isophotes in SIDM models with increasing cross-sections are rounder than their CDM counterparts, which manifests as a systematic shift in the distribution function of ellipticities. Unexpectedly, the X-ray morphology of the observed non-cool-core clusters agrees better with SIDM models with cross-section  |$(\sigma /m)= 0.5\!-\!1\, {\rm cm}^2\, {\rm g}^{-1}$| than CDM and SIDM with |$(\sigma /m)=0.1\, {\rm cm}^2\, {\rm g}^{-1}$|⁠. Our statistical analysis indicates that the latter two models are disfavoured at the |$68{{\ \rm per\ cent}}$| confidence level (as conservative estimates). This conclusion is not altered by shifting the radial range of measurements or applying a temperature selection criterion. However, the primary uncertainty originates from the lack of baryonic physics in the adiabatic model, such as cooling, star formation and feedback effects, which still have the potential to reconcile CDM simulations with observations. [ABSTRACT FROM AUTHOR]

Extended, steep, and ultra-steep spectrum radio emission in a galaxy cluster is usually associated with recent mergers. Simulations show that radio phoenixes are aged radio galaxy lobes whose emission reactivates when a low Mach shock compresses it. A85 hosts a textbook example of a radio phoenix at about 320 kpc southwest of the cluster centre. We present a new high-resolution 325 MHz GMRT radio map illustrating this radio phoenix's complex and filamentary structure. The full extent of the radio structure is revealed for the first time from these radio images of A85. Using archival Chandra X-ray observations, we applied an automated 2D shock finder to the X-ray surface brightness and Adaptive Circular Binning temperature maps that confirmed a bow shock at the location of the radio phoenix. We also compared the Mach number from the X-ray data with the radio-derived Mach number in the same region using multifrequency radio observations and find that they are consistent within the 1σ error level. [ABSTRACT FROM AUTHOR]

We present updated cosmological constraints from measurements of the gas mass fractions (f gas) of massive, dynamically relaxed galaxy clusters. Our new data set has greater leverage on models of dark energy, thanks to the addition of the Perseus cluster at low redshifts, two new clusters at redshifts z ≳ 1, and significantly longer observations of four clusters at 0.6 < z < 0.9. Our low-redshift (z < 0.16) f gas data, combined with the cosmic baryon fraction measured from the cosmic microwave background (CMB), imply a Hubble constant of h  = 0.722 ± 0.067. Combining the full f gas data set with priors on the cosmic baryon density and the Hubble constant, we constrain the dark energy density to be ΩΛ = 0.865 ± 0.119 in non-flat Lambda cold dark matter (cosmological constant) models, and its equation of state to be |$w=-1.13_{-0.20}^{+0.17}$| in flat, constant- w models, respectively 41 per cent and 29 per cent tighter than our previous work, and comparable to the best constraints available from other probes. Combining f gas, CMB, supernova, and baryon acoustic oscillation data, we also constrain models with global curvature and evolving dark energy. For the massive, relaxed clusters employed here, we find the scaling of f gas with mass to be consistent with a constant, with an intrinsic scatter that corresponds to just ∼3 per cent in distance. [ABSTRACT FROM AUTHOR]

We present results from Chandra X-ray observations and 325 MHz Giant Metrewave Radio Telescope (GMRT) observations of the massive and X-ray luminous cluster of galaxies Abell S1063. We report the detection of large-scale 'excess brightness' in the residual Chandra X-ray surface brightness map that extends at least 2.7 Mpc towards the north-east from the centre of the cluster. We also present a high fidelity X-ray flux and temperature map using Chandra archival data of 122 ks that shows the disturbed morphology in the cluster. The residual flux map shows the first observational confirmation of the merging axis proposed in earlier simulations. The average temperature within R 500 is 11.7 ± 0.56 keV that makes AS1063 one of the hottest clusters in the nearby Universe. The integrated radio flux density at 325 MHz is found to be 62.0 ± 6.3 mJy. The integrated spectrum of the radio halo follows a power law with a spectral index α = −1.43 ± 0.13. The radio halo is found to be significantly under-luminous that favored for both the hadronic as well as the turbulent re-acceleration mechanism for its origin. [ABSTRACT FROM AUTHOR]

The advent of sensitive low-frequency radio observations has revealed a number of diffuse radio objects with peculiar properties that are challenging our understanding of the physics of the intracluster medium. Here, we report the discovery of a steep-spectrum radio halo surrounding the central brightest cluster galaxy (BCG) in the galaxy cluster SPT-CL J2031−4037. This cluster is morphologically disturbed yet has a weak cool core, an example of a cool-core/non-cool-core transition system, which harbours a radio halo ∼0.7 Mpc in size. The halo emission detected at 1.7 GHz is less extended compared to that in the 325 MHz observation, and the spectral index of the part of the halo visible at the 325 MHz to 1.7 GHz frequencies was found to be −1.35 ± 0.07. Also, P 1.4 GHz was found to be 0.77 × 1024 W Hz−1, which falls in the region where radio mini-haloes, halo upper limits and ultra-steep-spectrum (USS) haloes are found in the P 1.4 GHz– L X plane. Additionally, simulations presented in the paper provide support for the scenario of the steep spectrum. The diffuse radio emission found in this cluster may be a steep-spectrum 'intermediate' or 'hybrid' radio halo that is transitioning into a mini-halo. [ABSTRACT FROM AUTHOR]

Scaling relations trace the formation and evolution of galaxy clusters. We exploited multi-wavelength surveys – the XXL survey at XMM-Newton in the X-ray band, and the Hyper Suprime-Cam Subaru Strategic Program for optical weak lensing – to study an X-ray selected, complete sample of clusters and groups. The scalings of gas mass, temperature, and soft-band X-ray luminosity with the weak lensing mass show imprints of radiative cooling and active galactic nucleus feedback in groups. From the multi-variate analysis, we found some evidence for steeper than self-similar slopes for gas mass (⁠|$\beta _{m_\text{g}|m}=1.73 \pm 0.80$|⁠) and luminosity (β l | m  = 1.91 ± 0.94) and a nearly self-similar slope for the temperature (β t | m  = 0.78 ± 0.43). Intrinsic scatters of X-ray properties appear to be positively correlated at a fixed mass (median correlation factor |$\rho _{X_1X_2|m}\sim 0.34$|⁠) due to dynamical state and merger history of the haloes. Positive correlations with the weak lensing mass (median correlation factor |$\rho _{m_\text{wl}X|m}\sim 0.35$|⁠) can be connected to triaxiality and orientation. Comparison of weak lensing and hydrostatic masses suggests a small role played by non-thermal pressure support (⁠|$9\pm 17{{\ \rm per\ cent}}$|⁠). [ABSTRACT FROM AUTHOR]

We present weak-lensing (WL) mass constraints for a sample of massive galaxy clusters detected by the South Pole Telescope (SPT) via the Sunyaev–Zel'dovich effect (SZE). We use griz imaging data obtained from the Science Verification (SV) phase of the Dark Energy Survey (DES) to fit the WL shear signal of 33 clusters in the redshift range 0.25 ≤ |$z$| ≤ 0.8 with NFW profiles and to constrain a four-parameter SPT mass–observable relation. To account for biases in WL masses, we introduce a WL mass to true mass scaling relation described by a mean bias and an intrinsic, lognormal scatter. We allow for correlated scatter within the WL and SZE mass–observable relations and use simulations to constrain priors on nuisance parameters related to bias and scatter from WL. We constrain the normalization of the ζ− M 500 relation, |$A_\mathrm{SZ}=12.0_{-6.7}^{+2.6}$| when using a prior on the mass slope B SZ from the latest SPT cluster cosmology analysis. Without this prior, we recover |$A_\mathrm{SZ}=10.8_{-5.2}^{+2.3}$| and |$B_\mathrm{SZ}=1.30_{-0.44}^{+0.22}$|⁠. Results in both cases imply lower cluster masses than measured in previous work with and without WL, although the uncertainties are large. The WL derived value of B SZ is |${\approx } 20{{\ \rm per\ cent}}$| lower than the value preferred by the most recent SPT cluster cosmology analysis. The method demonstrated in this work is designed to constrain cluster masses and cosmological parameters simultaneously and will form the basis for subsequent studies that employ the full SPT cluster sample together with the DES data. [ABSTRACT FROM AUTHOR]

The study aimed to evaluate possible differences between two genetic groups (GG) of pigs, fed diets varying in dietary CP level, in hematological and biochemical plasma profiles. The study was carried out in an experimental farm and involved 36 barrows (average BW 129 ± 11 kg) from two GG: group A (18 Italian Duroc boars × Italian Large White sows) and group D (18 DanBred Duroc), fed three experimental diets: a conventional diet and two low-protein diets (LP1 and LP2). A digestibility/balances trial was carried out on 12 pigs A and 12 pigs D that were housed individually in metabolic cages during four digestibility/balances periods. The experimental design was a factorial design, with 3 diets × 2 GG × 4 periods. The experiment lasted 56 d. Blood was sampled from jugular vein in the morning before feed distribution from all barrows in pens at the start and the end of the experimental period; a supplementary blood sample was collected from the 24 pigs at the end of the four digestibility periods (six pigs per period). Blood was analyzed for hematological and biochemical parameters and serum protein profile using automated analyzers. The GG D showed lower white blood cells (WBC), lymphocyte, and monocyte counts than A group. The GG affected several plasma metabolite concentrations: triglycerides, creatinine, Cl, Fe, alkaline phosphatase, and tartrate-resistant acid phosphatase activities were higher in D groups, while urea, albumin, Ca, Na, total bilirubin, and albumin as percentage of total protein were lower than A group. On the contrary, the dietary protein level neither affects WBC nor their populations; only a trend was reported for erythrocytes (red blood cell) and platelets. The diet affected only plasma urea and total bilirubin concentrations. [ABSTRACT FROM AUTHOR]

We perform dark-matter-only simulations of 28 relaxed massive cluster-sized haloes for cold dark matter (CDM) and self-interacting dark matter (SIDM) models, to study structural differences between the models at large radii, where the impact of baryonic physics is expected to be very limited. We find that the distributions for the radial profiles of the density, ellipsoidal axial ratios and velocity anisotropies (β) of the haloes differ considerably between the models (at the ∼1σ level), even at ≳ 10 per cent of the virial radius, if the self-scattering cross-section is σ/mχ = 1 cm² g-1. Direct comparison with observationally inferred density profiles disfavours SIDM for σ/mχ = 1 cm² g-1, but in an intermediate radial range (∼ 3 per cent of the virial radius), where the impact of baryonic physics is uncertain. At this level of the cross-section, we find a narrower β distribution in SIDM, clearly skewed towards isotropic orbits, with no SIDM (90 per cent of CDM) haloes having β > 0.12 at 7 per cent of the virial radius. We estimate that with an observational sample of ∼30 (∼1015 M⊙) relaxed clusters, β can potentially be used to put competitive constraints on SIDM, once observational uncertainties improve by a factor of a few. We study the suppression of the memory of halo assembly history in SIDM clusters. For σ/mχ = 1 cm² g-1, we find that this happens only in the central halo regions (∼1/4 of the scale radius of the halo), and only for haloes that assembled their mass within this region earlier than a formation redshift zf ∼ 2. Otherwise, the memory of assembly remains and is reflected in ways similar to CDM, albeit with weaker trends. [ABSTRACT FROM AUTHOR]

We constrain cold dark energy of negligible sound speed using galaxy cluster abundance observations. In contrast to standard quasi-homogeneous dark energy, negligible sound speed implies clustering of the dark energy fluid at all scales, allowing us to measure the effects of dark energy perturbations at cluster scales. We compare those models and set the stage for using non-linear information from semi-analytical modelling in cluster growth data analyses. For this, we recalibrate the halo mass function with non-linear characteristic quantities, the spherical collapse threshold and virial overdensity, that account for model and redshift-dependent behaviours, as well as an additional mass contribution for cold dark energy. We present the first constraints from this cold dark matter plus cold dark energy mass function using our cluster abundance likelihood, which self-consistently accounts for selection effects, covariances and systematic uncertainties. We combine cluster growth data with cosmic microwave background, supernovae Ia and baryon acoustic oscillation data, and find a shift between cold versus quasi-homogeneous dark energy of up to 1s. We make a Fisher matrix forecast of constraints attainable with cluster growth data from the ongoing Dark Energy Survey (DES). For DES, we predict ~50 per cent tighter constraints on (Ωm, w) for cold dark energy versus wCDM models, with the same free parameters. Overall, we show that cluster abundance analyses are sensitive to cold dark energy, an alternative, viable model that should be routinely investigated alongside the standard dark energy scenario. [ABSTRACT FROM AUTHOR]

Recent measurements of the cosmic microwave background (CMB) by the Planck Collaboration have produced arguably the most powerful observational evidence in support of the standard model of cosmology, i.e. the spatially flat ΛCDM paradigm. In this work, we perform model selection tests to examine whether the base CMB temperature and large scale polarization anisotropy data from Planck 2015 (P15; Planck Collaboration XIII) prefer any of eight commonly used one-parameter model extensions with respect to flat ΛCDM. We find a clear preference for models with free curvature, ΩK, or free amplitude of the CMB lensing potential, AL. We also further develop statistical tools to measure tension between data sets. We use a Gaussianization scheme to compute tensions directly from the posterior samples using an entropy-based method, the surprise, as well as a calibrated evidence ratio presented here for the first time. We then proceed to investigate the consistency between the base P15 CMB data and six other CMB and distance data sets. In flat ΛCDM we find a 4.8σ tension between the base P15 CMB data and a distance ladder measurement, whereas the former are consistent with the other data sets. In the curved ΛCDM model we find significant tensions in most of the cases, arising from the well-known low power of the low-l multipoles of the CMB data. In the flat ΛCDM+AL model, however, all data sets are consistent with the base P15 CMB observations except for the CMB lensing measurement, which remains in significant tension. This tension is driven by the increased power of the CMB lensing potential derived from the base P15 CMB constraints in both models, pointing at either potentially unresolved systematic effects or the need for new physics beyond the standard flat ΛCDM model. [ABSTRACT FROM AUTHOR]

This is the fourth in a series of papers studying the astrophysics and cosmology of massive, dynamically relaxed galaxy clusters. Here, we use measurements of weak gravitational lensing from the Weighing the Giants project to calibrate Chandra X-ray measurements of total mass that rely on the assumption of hydrostatic equilibrium. This comparison of X-ray and lensing masses measures the combined bias of X-ray hydrostatic masses from both astrophysical and instrumental sources. While we cannot disentangle the two sources of bias, only the combined bias is relevant for calibrating cosmological measurements using relaxed clusters. Assuming a fixed cosmology, and within a characteristic radius (r2500) determined from the X-ray data, we measure a lensing to X-ray mass ratio of 0.96 ± 9 per cent (stat) ± 9?per cent (sys). We find no significant trends of this ratio with mass, redshift or the morphological indicators used to select the sample. Our results imply that any departures from hydrostatic equilibrium at these radii are offset by calibration errors of comparable magnitude, with large departures of tens-of-percent unlikely. In addition, we find a mean concentration of the sample measured from lensing data of c200=3.0+4.4-1.8. Anticipated short-term improvements in lensing systematics, and a modest expansion of the relaxed lensing sample, can easily increase the measurement precision by 30-50 per cent, leading to similar improvements in cosmological constraints that employ X-ray hydrostatic mass estimates, such as on Ωm from the cluster gas mass fraction. [ABSTRACT FROM AUTHOR]

The aim of this work was to evaluate the effects of the inclusion of whole-ear corn silage (WECS) in diets for advanced fattening heavy pigs (substitution for part of the dry corn and wheat bran) allocated or not in metabolic cages on the main blood parameters. The high-moisture shelled corn is largely used in pig feeding while WECS is less often used despite the fact that it increases the DM crop yield. Three experimental diets were fed to 27 barrows (Italian Large White × Italian Duroc), with an average BW of 98.2 (±5.6) kg at the start of the trial, and randomly allotted to 3 experimental groups including a control diet (CON) containing cereal meals (corn, barley, and wheat, 80.2% DM in total), soybean meal (9% DM), wheat bran (8% DM), minerals and supplements (2.8% DM), and 2 diets containing WECS (15 or 30% DM referred to as 15WECS and 30WECS, respectively) in partial or complete substitution for wheat bran and corn meal. The pigs were randomly housed in 9 pens with 3 animals per pen and 3 pens per dietary treatment. Six pigs per each of the 3 treatments were moved from the pens to individual metabolic cages for 3 consecutive periods (2 pigs per treatment per period). Each period lasted 14 d, and blood was collected at the start and at the end of the periods. Blood was drawn from the jugular vein before feed distribution in the morning, at 14 d intervals, and analyzed for hematological, metabolic, and serum protein profiles. The effect of the metabolic cage housing was included in the statistical model to compare the results obtained in the 2 different environments of restrained and group-housed barrows. The WECS affected the neutrophil to lymphocyte ratio and mean corpuscular hemoglobin concentration. The main diet effect on plasma metabolites was recorded for plasma NEFA, with higher values in WECS diets compared with the CON. The metabolic cage housing affected both hematological (red blood cell count, hemoglobin, hematocrit) and metabolic (protein and its fractions) items, which can be markers of hemodilution. These results indicate the possibility to use this feed in the diet of heavy pigs without negative effects on physiology. The absolute values from metabolic profile of pigs in metabolic cages must be considered with caution for possible comparisons with values obtained on-field in group pens, particularly because a different hemodilution may affect the results. [ABSTRACT FROM AUTHOR]

We employ robust weak gravitational lensing measurements to improve cosmological constraints from measurements of the galaxy cluster mass function and its evolution, using X-ray selected clusters detected in the ROSAT All-Sky Survey. Our lensing analysis constrains the absolute mass scale of such clusters at the 8 per cent level, including both statistical and systematic uncertainties. Combining it with the survey data and X-ray follow-up observations, we find a tight constraint on a combination of the mean matter density and late-time normalization of the matter power spectrum, σ8(Ωm/0.3)0.17 = 0.81 ± 0.03, with marginalized, one-dimensional constraints of Ωm = 0.26 ± 0.03 and σ8 = 0.83 ± 0.04. For these two parameters, this represents a factor of 2 improvement in precision with respect to previous work, primarily due to the reduced systematic uncertainty in the absolute mass calibration provided by the lensing analysis. Our new results are in good agreement with constraints from cosmic microwave background (CMB) data, both Wilkinson Microwave Anisotropy Probe (WMAP) and Planck (plus WMAP polarization), under the assumption of a flat ΛCDM cosmology with minimal neutrino mass. Consequently, we find no evidence for non-minimal neutrino mass from the combination of cluster data with CMB, supernova and baryon acoustic oscillation measurements, regardless of which all-sky CMB data set is used (and independent of the recent claimed detection of B modes on degree scales). We also present improved constraints on models of dark energy (both constant and evolving), modifications of gravity, and primordial non-Gaussianity. Assuming flatness, the constraints for a constant dark energy equation of state from the cluster data alone are at the 15 per cent level, improving to ~6 per cent when the cluster data are combined with other leading probes. [ABSTRACT FROM AUTHOR]

The increasing precision in the determination of the Hubble parameter has reached a per cent level at which large-scale cosmic flows induced by inhomogeneities of the matter distribution become non-negligible. Here, we use large-scale cosmological N-body simulations to study statistical properties of the local Hubble parameter as measured by local observers. We show that the distribution of the local Hubble parameter depends not only on the scale of inhomogeneities, but also on how one defines the positions of observers in the cosmic web and what reference frame is used. Observers located in random dark matter haloes measure on average lower expansion rates than those at random positions in space or in the centres of cosmic voids, and this effect is stronger from the halo rest frames compared to the cosmic microwave background (CMB) rest frame. We compare the predictions for the local Hubble parameter with observational constraints based on Type Ia supernova (SNIa) and CMB observations. Due to cosmic variance, for observers located in random haloes we show that the Hubble constant determined from nearby SNIa may differ from that measured from the CMB by ±0.8 per cent at 1σ statistical significance. This scatter is too small to significantly alleviate a recently claimed discrepancy between current measurements assuming a flat Λ cold dark matter (ΛCDM) model. However, for observers located in the centres of the largest voids permitted by the standard ΛCDM model, we find that Hubble constant measurements from SNIa would be biased high by 5 per cent, rendering this tension non-existent in this extreme case. [ABSTRACT FROM AUTHOR]

The aim was to evaluate 2 levels of dietary inclusion of chopped whole-ear corn silage (WECS) on energy and nutrient utilization, growth, and slaughter performances of heavy pigs. Two in vivo experiments were conducted to determine digestibility and metabolic utilization of WECS using 18 barrows weighing 118 ± 8 kg BW on average, metabolic cages and respiration chambers (Exp. 1), and the effect of WECS on the growth performance and carcass traits on 42 barrows from 90 to 170 kg BW (Exp. 2). In both experiments, pigs were fed 3 experimental diets: a control diet (CON) containing cereal meals, extracted soybean meal, and wheat bran (80%, 9%, and 8% of DM, respectively) and 2 diets containing 15% (15WECS) or 30% WECS (30WECS) on a DM basis in place of wheat bran and corn meal. The diets were prepared daily by mixing the WECS to a suitable compound feed. Feed intake was always restricted to allow a daily DMI of 7.2% BW0.75 in Exp. 1 and from 8.0% to 6.5% BW0 75 in Exp. 2. Diets had similar NDF contents (15.2% to 15.8% of DM), and WECS inclusion resulted in a slight reduction in CP content (from 14.0% to 13.6% of DM) and a considerable decrease in P content (from 0.47% to 0.30% of DM). Digestibility of OM, CP, and fat was similar among diets, whereas P digestibility was lower (P < 0.05) for the 30WECS diet (33.5%) in comparison with the CON and 15WECS diets (45.5% and 44.1%, respectively). Nitrogen lost in feces and urine and N retained were not different among diets, whereas P retained decreased with the increase of WECS (5.4, 3.7, and 2.2 g/d for the CON, 15WECS, and 30WECS diets, respectively; P < 0.05). No difference among diets was observed for energy balance. The WECS contained 13.48 MJ ME and 9.39 MJ NE/kg DM. In Exp. 2, feed intake was not depressed by WECS inclusion, and the ADG for the whole experiment was not different among dietary treatments (from 737 to 774 g/d). Fecal pH was lower (P < 0.05) for the WECS diets than the control diet (7.10 and 7.00 vs. 7.40) and for the sampling at 150 kg BW than that at 130 and 110 kg BW (6.96 vs. 7.29 and 7.24). At slaughter, lean percentage in the carcass was lower in the 30WECS diet than those of the other 2 diets (46.8% vs. 48.3% and 48.6%, P = 0.05). The overall experimental data obtained in both trials indicate that substitution of wheat bran and com meal for WECS (up to 30% of DM) does not affect, with the exception of P utilization and carcass leanness, energy and nutrient utilization and performance of heavy pigs in the last phase of growing. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 24-year old man who was found unconscious following vomiting. He was undergoing treatment for depression since 2007. He had started consuming mesterolone tablets prior two weeks before death. Toxicological analyses showed that death occurred due to drug overdose. It concludes acute chloralose intoxication as a result of death.

This is the third of a series of papers in which we derive simultaneous constraints on cosmological parameters and X-ray scaling relations using observations of the growth of massive, X-ray flux-selected galaxy clusters. Our data set consists of 238 clusters drawn from the ROSAT All-Sky Survey and incorporates extensive follow-up observations using the Chandra X-ray Observatory. Here we present improved constraints on departures from general relativity (GR) on cosmological scales, using the growth index, γ, to parametrize the linear growth rate of cosmic structure. Using the method of Mantz et al. (Paper I), we simultaneously and self-consistently model the growth of X-ray luminous clusters and their observable–mass scaling relations, accounting for survey biases, parameter degeneracies and the impact of systematic uncertainties. Such analysis of the survey and follow-up data is crucial, else spurious constraints may be obtained. We combine the X-ray cluster growth data with cluster gas mass fraction, Type Ia supernova, baryon acoustic oscillation and cosmic microwave background data. We find that the combination of these data leads to a tight correlation between γ and the normalization of the matter power spectrum, σ8. Consistency with GR requires a measured growth index of . Under the assumption of self-similar evolution and constant scatter in the cluster observable–mass scaling relations, and for a spatially flat model with a cosmological constant, we measure , with allowed values for σ8 in the range of 0.79–0.89 (68.3 per cent confidence limits). Relaxing the assumptions on the scaling relations by introducing two additional parameters to model possible evolution in the normalization and scatter of the luminosity–mass relation, we obtain consistent constraints on γ that are only per cent weaker than those above. Allowing the dark energy equation of state, w, to take any constant value, we simultaneously constrain the growth and expansion histories and find no evidence for departures from either GR or the cosmological constant plus cold dark matter paradigm. Our results represent the most robust consistency test of GR on cosmological scales to date. [ABSTRACT FROM AUTHOR]

This is the fourth of a series of papers in which we derive simultaneous constraints on cosmological parameters and X-ray scaling relations using observations of the growth of massive, X-ray flux-selected galaxy clusters. Our data set consists of 238 clusters drawn from the ROSAT All-Sky Survey and incorporates extensive follow-up observations using the Chandra X-ray Observatory. Here we examine the constraints on neutrino properties that are enabled by the precise and robust constraint on the amplitude of the matter power spectrum at low redshift available from our data. In combination with cluster gas mass fraction, cosmic microwave background, supernova and baryon acoustic oscillation data, and incorporating conservative allowances for systematic uncertainties, we limit the species-summed neutrino mass, , to at 95.4 per cent confidence in a spatially flat, cosmological constant (ΛCDM) model. In a flat ΛCDM model where the effective number of neutrino species, Neff, is allowed to vary, we find (68.3 per cent confidence, incorporating a direct constraint on the Hubble parameter from Cepheid and supernova data). We also obtain results with additional degrees of freedom in the cosmological model, in the form of global spatial curvature (Ωk) and a primordial spectrum of tensor perturbations ( r and ). The results are not immune to these generalizations; however, in the most general case we consider, in which , curvature and tensors are all free, we still obtain and (at, respectively, the same confidence levels as above). These results agree well with recent work using independent data and highlight the importance of measuring cosmic structure and expansion at low as well as high redshifts. Although our cluster data extend to redshift , the direct effect of neutrino mass on the growth of structure at late times is not yet detected at a significant level. [ABSTRACT FROM AUTHOR]

This is the first of a series of papers in which we derive simultaneous constraints on cosmological parameters and X-ray scaling relations using observations of the growth of massive, X-ray flux-selected galaxy clusters. Our data set consists of 238 cluster detections from the ROSAT All-Sky Survey, and incorporates follow-up observations of 94 of those clusters using the Chandra X-ray Observatory or ROSAT. Here we describe and implement a new statistical framework required to self-consistently produce simultaneous constraints on cosmology and scaling relations from such data, and present results on models of dark energy. In spatially flat models with a constant dark energy equation of state, w, the cluster data yield and , incorporating standard priors on the Hubble parameter and mean baryon density of the Universe, and marginalizing over conservative allowances for systematic uncertainties. These constraints agree well and are competitive with independent data in the form of cosmic microwave background anisotropies, type Ia supernovae, cluster gas mass fractions, baryon acoustic oscillations, galaxy redshift surveys and cosmic shear. The combination of our data with current microwave background, supernova, gas mass fraction and baryon acoustic oscillation data yields and for flat, constant w models. The combined data also allow us to investigate evolving w models. Marginalizing over transition redshifts in the range 0.05–1, we constrain the equation of state at late and early times to be respectively and , again including conservative systematic allowances. The combined data provide constraints equivalent to a Dark Energy Task Force figure of merit of 15.5. Our results highlight the power of X-ray studies, which enable the straightforward production of large, complete and pure cluster samples and admit tight scaling relations, to constrain cosmology. However, the new statistical framework we apply to this task is equally applicable to cluster studies at other wavelengths. [ABSTRACT FROM AUTHOR]

This is the second in a series of papers in which we derive simultaneous constraints on cosmology and X-ray scaling relations using observations of massive, X-ray flux-selected galaxy clusters. The data set consists of 238 clusters with 0.1–2.4 keV luminosities , and incorporates follow-up observations of 94 of those clusters using the Chandra X-ray Observatory or ROSAT (11 were observed with both). The clusters are drawn from three samples based on the ROSAT All-Sky Survey: the ROSAT Brightest Cluster Sample (78/37 clusters detected/followed-up), the ROSAT-ESO Flux-Limited X-ray sample (126/25) and the bright sub-sample of the Massive Cluster Survey (34/32). Our analysis accounts self-consistently for all selection effects, covariances and systematic uncertainties. Here we describe the reduction of the follow-up X-ray observations, present results on the cluster scaling relations, and discuss their implications. Our constraints on the luminosity–mass and temperature–mass relations, measured within r500, lead to three important results. First, the data support the conclusion that excess heating of the intracluster medium (or a combination of heating and condensation of the coldest gas) has altered its thermodynamic state from that expected in a simple, gravitationally dominated system; however, this excess heat is primarily limited to the central regions of clusters . Secondly, the intrinsic scatter in the centre-excised luminosity–mass relation is remarkably small, being bounded at the <10 per cent level in current data; for the hot, massive clusters under investigation, this scatter is smaller than in either the temperature–mass or –mass relations (10–15 per cent). Thirdly, the evolution with redshift of the scaling relations is consistent with the predictions of simple, self-similar models of gravitational collapse, indicating that the mechanism responsible for heating the central regions of clusters was in operation before redshift 0.5 (the limit of our data) and that its effects on global cluster properties have not evolved strongly since then. Our results provide a new benchmark for comparison with numerical simulations of cluster formation and evolution. [ABSTRACT FROM AUTHOR]

We use measurements of the growth of cosmic structure, as inferred from the observed evolution of the X-ray luminosity function (XLF) of galaxy clusters, to constrain departures from general relativity (GR) on cosmological scales. We employ the popular growth rate parameterization, , for which GR predicts a growth index . We use observations of the cosmic microwave background (CMB), type Ia supernovae (SNIa) and X-ray cluster gas mass fractions ( fgas), to simultaneously constrain the expansion history and energy content of the Universe, as described by the background model parameters: and Ωk, i.e. the mean matter density, the dark energy equation of state parameter and the mean curvature, respectively. Using conservative allowances for systematic uncertainties, in particular for the evolution of the mass–luminosity scaling relation in the XLF analysis, we find and (68.3 per cent confidence limits), for a flat cosmological constant, cold dark matter (ΛCDM) background model. Allowing w to be a free parameter, we find . Relaxing the flatness prior in the ΛCDM model, we obtain . When in addition to the XLF data we use the CMB data to constrain γ through the ISW effect, we obtain a combined constraint of for the flat ΛCDM model. Our analysis provides the tightest constraints to date on the growth index. We find no evidence for departures from GR on cosmological scales. [ABSTRACT FROM AUTHOR]

Macroeconomic theory will surely be affected by the current global crisis. There are signs that some 'old' theories and insights will have a comeback. This paper argues that among them economists should not forget the lessons that have been learnt from three decades of several financial crises in developing countries. We emphasise two important lessons. First, preventing crises in developing countries requires not only the regulation of domestic financial systems, but also a consistent set of macroeconomic policies. In particular we stress the need for consistency between the exchange rate rule, the capital account regime and the domestic financial market regulations. Second, financial crises in developing countries tend to worsen both the balance of payments and the fiscal balance. Traditional adjustment policies tend to exacerbate the recessive trends in output and employment. This is just the opposite of what is required and what governments in developed countries are able to do. Developing countries should push for an agenda that helps them deal with these problems. [ABSTRACT FROM AUTHOR]

We examine the ability of a future X-ray observatory, with capabilities similar to those planned for the Constellation-X or X-ray Evolving Universe Spectroscopy (XEUS) missions, to constrain dark energy via measurements of the cluster X-ray gas mass fraction, fgas. We find that fgas measurements for a sample of ∼500 hot ( kT≳ 5 keV), X-ray bright, dynamically relaxed clusters, to a precision of ∼5 per cent, can be used to constrain dark energy with a Dark Energy Task Force (DETF) figure of merit of 15–40, with the possibility of boosting these values by 40 per cent or more by optimizing the redshift distribution of target clusters. Such constraints are comparable to those predicted by the DETF for other leading, planned ‘Stage IV’ dark energy experiments. A future fgas experiment will be preceded by a large X-ray or Sunyaev–Zel'dovich survey that will find hot, X-ray luminous clusters out to high redshifts. Short ‘snapshot’ observations with the new X-ray observatory should then be able to identify a sample of ∼500 suitably relaxed systems. The redshift, temperature and X-ray luminosity range of interest has already been partially probed by existing X-ray cluster surveys which allow reasonable estimates of the fraction of clusters that will be suitably relaxed for fgas work to be made; these surveys also show that X-ray flux contamination from point sources is likely to be small for the majority of the targets of interest. Our analysis uses a Markov Chain Monte Carlo method which fully captures the relevant degeneracies between parameters and facilitates the incorporation of priors and systematic uncertainties in the analysis. We explore the effects of such uncertainties for scenarios ranging from optimistic to pessimistic. We conclude that the fgas experiment offers a competitive and complementary approach to the best other large, planned dark energy experiments. In particular, the fgas experiment will provide tight constraints on the mean matter and dark energy densities, with a peak sensitivity for dark energy work at redshifts mid-way between those of supernovae and baryon acoustic oscillation/weak lensing/cluster number count experiments. In combination, these experiments should enable a precise measurement of the evolution of dark energy. [ABSTRACT FROM AUTHOR]

We present constraints on the mean matter density, Ωm, the normalization of the density fluctuation power spectrum, σ8, and the dark energy equation of state parameter, w, obtained from measurements of the X-ray luminosity function of the largest known galaxy clusters at redshifts z < 0.7, as compiled in the Massive Cluster Survey (MACS) and the local Brightest Cluster Sample (BCS) and ROSAT–ESO Flux Limited X-Ray (REFLEX) galaxy cluster sample. Our analysis employs an observed mass–luminosity relation, calibrated by hydrodynamical simulations, including corrections for non-thermal pressure support and accounting for the presence of intrinsic scatter. Conservative allowances for all known systematic uncertainties are included, as are standard priors on the Hubble constant and mean baryon density. We find and for a spatially flat, cosmological constant model, and and for a flat, constant w model (marginalized 68 per cent confidence intervals). Our findings constitute the first determination of the dark energy equation of state from measurements of the growth of cosmic structure in galaxy clusters, and the consistency of our result with w=−1 lends additional support to the cosmological constant model. Future work improving our understanding of redshift evolution and observational biases affecting the mass–X-ray luminosity relation have the potential to significantly tighten these constraints. Our results are consistent with those from recent analyses of Type Ia supernovae, cosmic microwave background anisotropies, the X-ray gas mass fraction of relaxed galaxy clusters, baryon acoustic oscillations and cosmic shear. Combining the new X-ray luminosity function data with current supernova, cosmic microwave background and cluster gas fraction data yields the improved constraints and . [ABSTRACT FROM AUTHOR]

We present constraints on the mean matter density, Ωm, dark energy density, ΩDE, and the dark energy equation of state parameter, w, using Chandra measurements of the X-ray gas mass fraction ( fgas) in 42 hot ( kT > 5 keV), X-ray luminous, dynamically relaxed galaxy clusters spanning the redshift range 0.05 < z < 1.1. Using only the fgas data for the six lowest redshift clusters at z < 0.15, for which dark energy has a negligible effect on the measurements, we measure (68 per cent confidence limits, using standard priors on the Hubble constant, H0, and mean baryon density, ). Analysing the data for all 42 clusters, employing only weak priors on H0 and , we obtain a similar result on Ωm and a detection of the effects of dark energy on the distances to the clusters at ∼99.99 per cent confidence, with for a non-flat ΛCDM model. The detection of dark energy is comparable in significance to recent type Ia supernovae (SNIa) studies and represents strong, independent evidence for cosmic acceleration. Systematic scatter remains undetected in the fgas data, despite a weighted mean statistical scatter in the distance measurements of only ∼5 per cent. For a flat cosmology with a constant dark energy equation of state, we measure and w=−1.14 ± 0.31. Combining the fgas data with independent constraints from cosmic microwave background and SNIa studies removes the need for priors on and H0 and leads to tighter constraints: and w=−0.98 ± 0.07 for the same constant- w model. Our most general analysis allows the equation of state to evolve with redshift. Marginalizing over possible transition redshifts 0.05 < zt < 1, the combined fgas+ CMB + SNIa data set constrains the dark energy equation of state at late and early times to be and , respectively, in agreement with the cosmological constant paradigm. Relaxing the assumption of flatness weakens the constraints on the equation of state by only a factor of ∼2. Our analysis includes conservative allowances for systematic uncertainties associated with instrument calibration, cluster physics and data modelling. The measured small systematic scatter, tight constraint on Ωm and powerful constraints on dark energy from the fgas data bode well for future dark energy studies using the next generation of powerful X-ray observatories, such as Constellation-X. [ABSTRACT FROM AUTHOR]

We present and employ a new kinematical approach to cosmological ‘dark energy’ studies. We construct models in terms of the dimensionless second and third derivatives of the scalefactor a( t) with respect to cosmic time t, namely the present-day value of the deceleration parameter q0 and the cosmic jerk parameter, j( t). An elegant feature of this parametrization is that all Λ cold dark matter (ΛCDM) models have (constant), which facilitates simple tests for departures from the ΛCDM paradigm. Applying our model to the three best available sets of redshift-independent distance measurements, from Type Ia supernova and X-ray cluster gas mass fraction measurements, we obtain clear statistical evidence for a late-time transition from a decelerating to an accelerating phase. For a flat model with constant jerk, , we measure and , results that are consistent with ΛCDM at about the 1σ confidence level. A standard ‘dynamical’ analysis of the same data, employing the Friedmann equations and modelling the dark energy as a fluid with an equation-of-state parameter, w (constant), gives and , also consistent with ΛCDM at about the 1σ level. In comparison to dynamical analyses, the kinematical approach uses a different model set and employs a minimum of prior information, being independent of any particular gravity theory. The results obtained with this new approach therefore provide important additional information and we argue that both kinematical and dynamical techniques should be employed in future dark energy studies, where possible. Our results provide further interesting support for the concordance ΛCDM paradigm. [ABSTRACT FROM AUTHOR]

We present new constraints on the evolution of dark energy from an analysis of cosmic microwave background, supernova and X-ray galaxy cluster data. Our analysis employs a minimum of priors and exploits the complementary nature of these data sets. We examine a series of dark energy models with up to three free parameters: the current dark energy equation of statew0, the early-time equation of statewet, and the scalefactor at transitionat. From a combined analysis of all three data sets, assuming a constant equation of state and that the Universe is flat, we measure. Includingwet as a free parameter and allowing the transition scalefactor to vary over the rangewhere the data sets have discriminating power, we measureand. We find no significant evidence for evolution in the dark energy equation-of-state parameter with redshift. Marginal hints of evolution in the supernovae data become less significant when the cluster constraints are also included in the analysis. The complementary nature of the data sets leads to a tight constraint on the mean matter densityΩm and alleviates a number of other parameter degeneracies, including that between the scalar spectral indexns, the physical baryon densityand the optical depthτ. This complementary nature also allows us to examine models in which we drop the prior on the curvature. For non-flat models with a constant equation of state, we measureand obtain a tight constraint on the current dark energy density. For dark energy models other than a cosmological constant, energy–momentum conservation requires the inclusion of spatial perturbations in the dark energy component. Our analysis includes such perturbations, assuming a sound speedin the dark energy fluid as expected for quintessence scenarios. For our most general dark energy model, not including such perturbations would lead to spurious constraints onwet, which would be tighter than those mentioned above by approximately a factor of 2 with the current data. [ABSTRACT FROM AUTHOR]

The immunological responses of the armadillo are of interest because of its susceptibility to generalized lepromatoid infection with Mycobacterium leprae. In this study, specimens of Dasypus sabanicola were found to have a typical mammalian distribution of lymphoid cells in thymus, spleen, lymph nodes and blood. Their complement was active in bactericidal, protozoan immobilization and haemolytic systems. Blood lymphocytes responded to phytohaemagglutinin and to pokeweed mitogen. Sensitization with ovalbumin in CFA resulted in the production of circulating precipitins; strong Arthus reactions were detectable in the sensitized animals. Responses of cell-mediated immunity to DNCB and to M. tuberculosis were very discrete. Heat-killed M. leprae elicited granulomatous reactions characterized by microscopic necrosis, but without abundant lymphocytic infiltration; skin tests and lymphocytic transformation were generally negative in the animals injected with M. leprae. [ABSTRACT FROM AUTHOR]