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Context. Photoevaporation is an important process for protoplanetary disc dispersal, but there has so far been a lack of consensus from simulations over the mass-loss rates and the most important part of the high-energy spectrum involved in driving the wind. Aims. We aim to isolate the origins of these discrepancies through carefully benchmarked hydrodynamic simulations of X-ray photoevaporation with time-dependent thermochemistry calculated on the fly. Methods. We conducted hydrodynamic simulations with PLUTO where the thermochemistry is calculated using PRIZMO. We explored the contribution of certain key microphysical processes and the impact of employing different spectra previously used in literature studies. Results. We find that additional cooling results from the excitation of O by neutral H, which leads to dramatically reduced mass-loss across the disc compared to previous X-ray photoevaporation models, with an integrated rate of ~10−9 M⊙ yr−1. Such rates would allow for longer-lived discs than previously expected from population synthesis. An alternative spectrum with less soft X-ray produces mass-loss rates around a factor of two to three times lower. The chemistry is significantly out of equilibrium, with the survival of H2 into the wind being aided by advection. This leads to H2 becoming the dominant coolant at 10s au, thus stabilising a larger radial temperature gradient across the wind as well as providing a possible wind tracer. [ABSTRACT FROM AUTHOR]

Context. Cosmic rays (CRs) heavily impact the chemistry and physics of cold and dense star-forming regions. However, the characterisation of their ionisation rate continues to pose a challenge from the observational point of view. Aims. In the past, a few analytical formulas have been proposed to infer the cosmic-ray ionisation rate, ζ2, from molecular line observations. These have been derived from the chemical kinetics of the involved species, but they have not yet been validated using synthetic data processed with a standard observative pipeline. In this work, we aim to bridge this gap. Methods. We performed a radiative transfer on a set of three-dimensional magneto-hydrodynamical simulations of prestellar cores, exploring different initial ζ2, evolutionary stages, types of radiative transfer (for instance assuming local-thermodynamic-equilibrium conditions), and telescope responses. We then computed the column densities of the involved tracers to determine ζ2, employing a recently proposed method based on the detection of H2D+. We compared this approach with a previous method, based on more common tracers. Both approaches are commonly used. Results. Our results confirm that the equation based on the detection of H2D+ accurately retrieves the actual ζ2 within a factor of two to three in the physical conditions explored in our tests. Since we have also explored a non-local thermodynamic equilibrium (non-LTE) radiative transfer, this work indirectly offers insights into the excitation temperatures of common transitions at moderate volume densities (n ≈ 105 cm−3). We also performed a few tests using a previous methodology that is independent of H2D+, which overestimates the actual ζ2 by at least two orders of magnitude. We considered a new derivation of this method, however, we found that it still leads to high over-estimations. Conclusions. The method based on H2D+ is further validated in this work and demonstrates a reliable method for estimating ζ2 in cold and dense gas. On the contrary, the former analytical equation, as already pointed out by its authors, has no global domain of application. Thus, we find that it ought to be employed with caution. [ABSTRACT FROM AUTHOR]

Background: In patients with type 2 diabetes mellitus (DM), an accurate assessment of food intake is essential for clinical nutritional management. Tools such as the food frequency questionnaire (FFQ) and 24‐h food record (24HR) identify dietary habits in support of dietary planning. However, it is possible that these tools have reporting errors with respect to assessing food intake, particularly energy intake (EI). Methods: A cross‐sectional study was conducted in patients with type 2 DM. EI was assessed by the FFQ and 24HR tools. Resting energy expenditure (REE) was measured by indirect calorimetry. Data were analysed using a kappa test, t‐test and Spearman's correlation coefficients. Under‐reporting was assessed using the EI/REE ratio. Patients with values <1.18 and <1.10 for FFQ and 24HR, respectively, were considered as under‐reporting. Results: We evaluated 55 patients [mean (SD) 62.7 (5.3) years old, duration of diabetes 11.2 (7.3) years, 52.7% female]. The mean (SD) EI assessed by FFQ was 1797.7 (641.3) and as assessed by 24HR was 1624 (484.8) kcal day–1. The mean (SD) REE was 1641.3 (322.3) kcal day–1. The mean (SD) ratios FFQ/REE and 24HR/REE were 1.11 (0.38) and 1.01 (0.30), respectively. The tools showed a moderate agreement for under‐reporting of EI (kappa = 0.404; P = 0.003). Moderate and positive correlations between REE were observed with FFQ (r = 0.321; P = 0.017) and 24HR (r = 0.364; P = 0.006). According to the tools, the under‐reporting was observed in approximately 65% of patients. Conclusions: The majority of patients with type 2 DM under‐reported their calorie intake, as assessed by FFQ and 24HR. REE showed a positive correlation with both tools. [ABSTRACT FROM AUTHOR]

The evaporation of molecules from dust grains is crucial to understanding some key aspects of the star- and the planet-formation processes. During the heating phase, the presence of young protostellar objects induces molecules to evaporate from the dust surface into the gas phase, enhancing its chemical complexity. Similarly, in circumstellar discs, the position of the so-called snow lines is determined by evaporation, with important consequences for the formation of planets. The amount of molecules that are desorbed depends on the interaction between the species and the grain surface, which is controlled by the binding energy. Recent theoretical and experimental works point towards a distribution of values for this parameter instead of the single value often employed in astrochemical models.We present a new "multi-binding energy" framework to assess the effects that a distribution of binding energies has on the amount of species bound to the grains. We find that the efficiency of the surface chemistry is significantly influenced by this process, with crucial consequences on the theoretical estimates of the desorbed species. [ABSTRACT FROM AUTHOR]

The dispersal phase of planet-forming discs via winds driven by irradiation from the central star and/or magnetic fields in the disc itself is likely to play an important role in the formation and evolution of planetary systems. Current theoretical models lack predictive power to adequately constrain observations. We present prizmo , a code for evolving thermochemistry in protoplanetary discs capable of being coupled with hydrodynamical and multifrequency radiative transfer codes. We describe the main features of the code, including gas and surface chemistry, photochemistry, microphysics, and the main cooling and heating processes. The results of a suite of benchmarks, which include photon-dominated regions, slabs illuminated by radiation spectra that include X-ray, and well-established cooling functions evaluated at different temperatures, show good agreement both in terms of chemical and thermal structures. The development of this code is an important step to perform quantitative spectroscopy of disc winds, and ultimately the calculation of line profiles, which is urgently needed to shed light on the nature of observed disc winds. [ABSTRACT FROM AUTHOR]

Context. Reliable, directly measured optical properties of astrophysical ice analogues in the infrared and terahertz (THz) range are missing from the literature. These parameters are of great importance to model the dust continuum radiative transfer in dense and cold regions, where thick ice mantles are present, and are necessary for the interpretation of future observations planned in the far-infrared region. Aims. Coherent THz radiation allows for direct measurement of the complex dielectric function (refractive index) of astrophysically relevant ice species in the THz range. Methods. We recorded the time-domain waveforms and the frequency-domain spectra of reference samples of CO ice, deposited at a temperature of 28.5 K and annealed to 33 K at different thicknesses. We developed a new algorithm to reconstruct the real and imaginary parts of the refractive index from the time-domain THz data. Results. The complex refractive index in the wavelength range 1 mm–150 μm (0.3–2.0 THz) was determined for the studied ice samples, and this index was compared with available data found in the literature. Conclusions. The developed algorithm of reconstructing the real and imaginary parts of the refractive index from the time-domain THz data enables us, for the first time, to determine the optical properties of astrophysical ice analogues without using the Kramers–Kronig relations. The obtained data provide a benchmark to interpret the observational data from current ground-based facilities as well as future space telescope missions, and we used these data to estimate the opacities of the dust grains in presence of CO ice mantles. [ABSTRACT FROM AUTHOR]

From molecular clouds to protoplanetary discs, non-ideal magnetic effects are important in many astrophysical environments. Indeed, in star and disc formation processes, it has become clear that these effects are critical to the evolution of the system. The efficacy of non-ideal effects is, however, determined by the complex interplay between magnetic fields, ionizing radiation, cosmic rays, microphysics, and chemistry. In order to understand these key microphysical parameters, we present a one-dimensional non-ideal magnetohydrodynamics code and apply it to a model of a time-dependent, oblique, magnetic shock wave. By varying the microphysical ingredients of the model, we find that cosmic rays and dust play a major role, and that, despite the uncertainties, the inclusion of microphysics is essential to obtain a realistic outcome in magnetic astrophysical simulations. [ABSTRACT FROM AUTHOR]

Aims. We present and test chemical models for three-dimensional hydrodynamical simulations of galaxies. We explore the effect of changing key parameters such as metallicity, radiation, and non-equilibrium versus equilibrium metal cooling approximations on the transition between the gas phases in the interstellar medium. Methods. The microphysics was modelled by employing the public chemistry package KROME, and the chemical networks were tested to work in a wide range of densities and temperatures. We describe a simple H/He network following the formation of H2 and a more sophisticated network that includes metals. Photochemistry, thermal processes, and different prescriptions for the H2 catalysis on dust are presented and tested within a one-zone framework. The resulting network is made publicly available on the KROME webpage. Results. We find that employing an accurate treatment of the dust-related processes induces a faster HI-H2 transition. In addition, we show when the equilibrium assumption for metal cooling holds and how a non-equilibrium approach affects the thermal evolution of the gas and the HII-HI transition. Conclusions. These models can be employed in any hydrodynamical code via an interface to KROME and can be applied to different problems including isolated galaxies, cosmological simulations of galaxy formation and evolution, supernova explosions in molecular clouds, and the modelling of star-forming regions. The metal network can be used for a comparison with observational data of CII 158 μm emission both for high-redshift and for local galaxies. [ABSTRACT FROM AUTHOR]

Observations of high-redshift quasars at z > 6 indicate that they harbour supermassive black holes (SMBHs) of a billion solar masses. The direct collapse scenario has emerged as the most plausible way to assemble SMBHs. The nurseries for the direct collapse black holes are massive primordial haloes illuminated with an intense UV flux emitted by Population II (Pop II) stars. In this study, we compute the critical value of such a flux (J21crit) for realistic spectra of Pop II stars through three-dimensional cosmological simulations. We derive the dependence of J21crit on the radiation spectra, on variations from halo to halo, and on the impact of X-ray ionization. Our findings show that the value of J21crit is a few times 104 and only weakly depends on the adopted radiation spectra in the range between Trad = 2 × 104 and 105 K. For three simulated haloes of a few times 107 M⊙, J21crit varies from 2 × 104 to 5 × 104. The impact of X-ray ionization is almost negligible and within the expected scatter of J21crit for background fluxes of JX,21 ≤ 0.1. The computed estimates of J21crit have profound implications for the quasar abundance at z = 10 as it lowers the number density of black holes forming through an isothermal direct collapse by a few orders of magnitude below the observed black hole density. However, the sites with moderate amounts of H2 cooling may still form massive objects sufficient to be compatible with observations. [ABSTRACT FROM AUTHOR]

The ability of metal-free gas to cool by molecular hydrogen in primordial haloes is strongly associated with the strength of ultraviolet (UV) flux produced by the stellar populations in the first galaxies. Depending on the stellar spectrum, these UV photons can either dissociate H2 molecules directly or indirectly by photodetachment of H− as the latter provides the main pathway for H2 formation in the early universe. In this study, we aim to determine the critical strength of the UV flux above which the formation of molecular hydrogen remains suppressed for a sample of five distinct haloes at z > 10 by employing a higher order chemical solver and a Jeans resolution of 32 cells. We presume that such flux is emitted by Pop II stars implying atmospheric temperatures of 104 K. We performed three-dimensional cosmological simulations and varied the strength of the UV flux below the Lyman limit in units of J21. Our findings show that the value of $J_{21}^{\rm crit}$ varies from halo to halo and is sensitive to the local thermal conditions of the gas. For the simulated haloes, it varies from 400 to 700 with the exception of one halo where $J_{21}^{\rm crit} \ge 1500$. This has important implications for the formation of direct collapse black holes and their estimated population at z > 6. It reduces the number density of direct collapse black holes by almost three orders of magnitude compared to the previous estimates. [ABSTRACT FROM PUBLISHER]

Introduction: Genotoxic biomarkers have been studied largely in adult population, but few studies so far have investigated them in children exposed to air pollution. Children are a high-risk group as regards the health effects of air pollution and some studies suggest that early exposure during childhood can play an important role in the development of chronic diseases in adulthood. The objective of the project is to evaluate the associations between the concentration of urban air pollutants and biomarkers of early biological effect in children, and to propose a model for estimating the global risk of early biological effects due to air pollutants and other factors in children. Methods and analysis: Two biomarkers of early biological effects, DNA damage by the comet assay and the micronuclei (MN) test, will be investigated in oral mucosa cells of 6-8-year-old children. Concurrently, some toxic airborne pollutants (polycyclic aromatic hydrocarbon (PAH) and nitro-PAH) and in vitro air mutagenicity and toxicity in ultra-fine air particulates (PM0.5) will be evaluated. Furthermore, demographic and socioeconomic variables, other sources of exposures to air pollutants and lifestyle variables will be assessed by a structured questionnaire. The associations between sociodemographic, environmental and other exposure variables and biomarkers of early biological effect using univariate and multivariate models will be analysed. A tentative model for calculating the global absolute risk of having early biological effects caused by air pollution and other variables will be proposed. Ethics and dissemination: The project has been approved by the Ethics Committees of the local Health Authorities. The results will be communicated to local Public Health Agencies, for supporting educational programmes and health policy strategies. LIFE+2012 Environment Policy and Governance. LIFE12 ENV/IT/ 000614. [ABSTRACT FROM AUTHOR]

While Population III (Pop III) stars are typically thought to be massive, pathways towards lower mass Pop III stars may exist when the cooling of the gas is particularly enhanced. A possible route is enhanced HD cooling during the merging of dark-matter haloes. The mergers can lead to a high ionization degree catalysing the formation of HD molecules and may cool the gas down to the cosmic microwave background temperature. In this paper, we investigate the merging of mini-haloes with masses of a few 105 M⊙ and explore the feasibility of this scenario. We have performed three-dimensional cosmological hydrodynamics calculations with the enzo code, solving the thermal and chemical evolution of the gas by employing the astrochemistry package krome. Our results show that the HD abundance is increased by two orders of magnitude compared to the no-merging case and the halo cools down to ∼60 K triggering fragmentation. Based on Jeans estimates, the expected stellar masses are about 10 M⊙. Our findings show that the merging scenario is a potential pathway for the formation of low-mass stars. [ABSTRACT FROM AUTHOR]

Context. Population III stars are the first stars in the Universe to form at z = 20-30 out of a pure hydrogen and helium gas in minihalos of 105-106 M☉. Cooling and fragmentation is thus regulated via molecular hydrogen. At densities above 108 cm-3, the three-body H2 formation rates are particularly important for making the gas fully molecular. These rates were considered to be uncertain by at least a few orders of magnitude. Aims. We explore the impact of recently derived accurate three-body H2 formation for three different minihalos, and compare them with the results obtained with three-body rates employed in previous other studies. Methods. The calculations were performed with the cosmological hydrodynamics code ENZO (release 2.2) coupled with the chemistry package KROME (including a network for primordial chemistry), which was previously shown to be accurate in high-resolution simulations. Results. While the new rates can shift the point where the gas becomes fully molecular, leading to a different thermal evolution, there is no trivial trend in the way this occurs. While one might naively expect the results to follow the rate coeffcients trend, the behavior can vary depending on the dark-matter halo that is explored. Conclusions. We conclude that employing the correct three-body rates is about equally important as the use of appropriate initial conditions, and that the resulting thermal evolution needs to be calculated for every halo individually. [ABSTRACT FROM AUTHOR]

The elementary mechanisms through which molecular polyynes could form stable negative ions after interacting with free electrons in planetary atmospheres (e.g., Titan's) are analyzed using quantum scattering calculations and quantum structure methods. The case of radical species and of nonpolar partners are analyzed via specific examples for both the CnH and HCnH series, with n values from 4 to 12. We show that attachment processes to polar radicals are dominating the anionic production and that the mediating role of dipolar scattering states is crucial to their formation. The corresponding attachment rates are presented as calculated upper limits to their likely values and are obtained down to the low temperatures of interest. The effects of the computed rates, when used in simple evolutionary models, are also investigated and presented in detail. [ABSTRACT FROM AUTHOR]

Hepatitis E virus ( HEV) is considered an emerging pathogen in industrialized countries. The occurrence of HEV genotypes in samples of faeces from asymptomatic migrants arriving on the coasts of South Italy and environmental samples was investigated. Analyses of sequences were used to compare human and environmental genotypes. A total of 40 stool specimens, 12 samples of untreated urban sewage, 12 samples of treated urban sewage and 12 samples of surface water were analysed. Viruses were concentrated from water samples by the tangential flow ultrafiltration technique. The presence of HEV RNA was detected by nested RT- PCR. Viral isolates were sequenced and phylogenetically characterized. Two (5%) of the 40 faecal samples tested were found to be positive for HEV RNA (G1 and G3 genotypes). The virus was detected in 25% (3/12) of the untreated sewage samples and 25% (3/12) of the surface water samples: all isolates belonged to G3 genotype. None of the treated sewage samples were found to be HEV RNA positive. The virus was detected in the faeces of two asymptomatic subjects, suggesting a potential role for symptom-free HEV carriers as a human reservoir. G3 HEV strains were detected in the untreated sewage, as observed in similar studies conducted in other European countries but differing from another study conducted in Italy recently. Moreover, our results show the first case of HEV isolated from fresh surface waters. [ABSTRACT FROM AUTHOR]

Chemistry plays a key role in the evolution of the interstellar medium, so it is highly important to follow its evolution in numerical simulations. However, it could easily dominate the computational cost when applied to large systems. In this paper we discuss two approaches to reduce these costs: (i) based on computational strategies, and (ii) based on the properties and on the topology of the chemical network. The first methods are more robust, while the second are meant to be giving important information on the structure of large, complex networks.We first discuss the numerical solvers for integrating the system of ordinary differential equations (ODE) associated with the chemical network, and then we propose a buffer method that decreases the computational time spent in solving the ODE system. We further discuss a flux-based method that allows one to determine and then cut on the fly the less active reactions.In addition we also present a topological approach for selecting the most probable species that will be active during the chemical evolution, thus gaining information on the chemical network that otherwise would be difficult to retrieve. This topological technique can also be used as an a priori reduction method for any size network.We implemented these methods into a 1D Lagrangian hydrodynamical code to test their effects: both classes lead to large computational speed-ups, ranging from ×2 to ×5. We have also tested some hybrid approaches finding that coupling the flux method with a buffer strategy gives the best trade-off between robustness and speed-up of calculations. [ABSTRACT FROM AUTHOR]

The time-dependent rate coefficients for the charge exchange reaction C+ + Si → C + Si+ for doublet and quartet states have been determined with ab initio quantum calculations coupled with a non-adiabatic transition model based on a simple Landau–Zener picture. This reaction plays a key role in determining the abundances of C, Si and their ions, in the interstellar medium since these abundances affect the fine-structure cooling and hence the star formation rates. We also provide additional calculations to evaluate the differences between the gas evolution as obtained by using the empirical rate estimates found in the current literature and the calculations presented in this work which are based on our more realistic evaluation of such rates from ab initio transition probabilities. We shall thus show here that the new rates yield important differences for metal-rich environments where T < 104 K and the ultraviolet flux is very small, while becoming less important at higher T values and higher photon fluxes. [ABSTRACT FROM AUTHOR]

The formation of anionic species in the interstellar medium from interaction of linear molecules containing carbon, nitrogen and hydrogen as atomic components (polyynes) with free electrons in the environment is modelled via a quantum treatment of the collision dynamics. The ensuing integral cross-sections are employed to obtain the corresponding attachment rates over a broad range of temperatures for the electrons. The calculations unequivocally show that a parametrization form often employed for such rates yields a broad range of values that turn out to be specific for each molecular species considered, thus excluding using a unique set for the whole class of polyynes. [ABSTRACT FROM PUBLISHER]

Context. The attachment of free electrons to polycondensed aromatic ring molecules (PAHs) is studied for the variety of these molecules with different numbers of condensed rings and over a broad range of electron temperatures, using a multichannel quantum scattering approach. The calculations of the relevant cross sections are used in turn to model the corresponding attachment rates for each of the systems under study, and these rates are parametrized as a function of temperature using a commonly employed expression for two-body processes in the interstellar medium (ISM). Aims. The scope of this work is to use first principles to establish the influence of chemical properties on the efficiency of the electronattachment process for PAHs. Methods. Quantum multichannel scattering methods are employed to generate the relevant cross sections, hence the attachment rates, using integral elastic cross sections computed over a broad range of relevant energies, from threshold up to 1000 K and linking the attachment to low-energy resonant collisions. Results. The rates obtained for the present molecules are found to markedly vary within the test ensemble of the present work and to be lower than the earlier values used for the entire class of PAHs anions, when modelling their evolutions in ISM environments. The effects of such differences on the evolutions of chemical networks that include both PAH and PAH-species are analysed in some detail and related to previous calculations. [ABSTRACT FROM AUTHOR]

ABSTRACT We investigate the influence of the initial overdensities and masses of proto-galaxies on their subsequent evolution (the star formation history in particular) to understand whether these key parameters are sufficient to account for the varied properties of the galactic populations. By means of fully hydrodynamical N-body simulations performed with the code E voL, we produce 12 self-similar models of early-type galaxies of different initial masses and overdensities, and follow their evolution from the early epochs (detachment from the linear regime and Hubble flow at z ≥ 20) down to the stage when mass assembly is complete, i.e. z ≤ 1 (in some cases the models are calculated up to z = 0). The simulations include radiative cooling, star formation, stellar energy feedback, re-ionizing photo-heating background and chemical enrichment of the interstellar medium; we do not consider the possible presence of active nuclei. We find a strong correlation between the initial properties of the proto-haloes and their subsequent star formation histories. Massive ( Mtot ≃ 1013 M⊙) haloes experience a single, intense burst of star formation (with rates ≥103 M⊙ yr−1) at early epochs, consistently with observations, with less pronounced dependence on the initial overdensity; intermediate-mass ( Mtot ≃ 1011 M⊙) haloes have histories that strongly depend on their initial overdensity, whereas low-mass haloes ( Mtot ≃ 109 M⊙) always have erratic, bursting like star-forming histories, due to the 'galactic breathing' phenomenon. The model galaxies have morphological, structural and chemical properties resembling those of real galaxies, even though some disagreement still occurs, likely a consequence of some numerical choices. We conclude that total mass and initial overdensity drive the star formation histories of early-type galaxies. The model galaxies belong to the so-called quasi-monolithic (or early hierarchical) scenario in the sense that the aggregation of lumps of dark and baryonic matter is completed very early on in their history. In this picture, nature seems to play the dominant role, whereas nurture has a secondary importance. [ABSTRACT FROM AUTHOR]

ABSTRACT We present a new computational scheme aimed at reducing the complexity of the chemical networks in astrophysical models, one which is shown to markedly improve their computational efficiency. It contains a flux-reduction scheme that permits us to deal with both large and small systems. This procedure is shown to yield a large speed-up of the corresponding numerical codes and provides good accord with the full network results. We analyse and discuss two examples involving chemistry networks of the interstellar medium and show that the results from the present reduction technique reproduce very well the results from fuller calculations. [ABSTRACT FROM AUTHOR]

The surveillance and monitoring of rotavirus (RV)-related diseases, preferably through the establishment of sentinel surveillance sites, are essential for assessing the need for vaccination and the projected results of the vaccine in terms of reducing the burden of disease. The objective of the present study was to compare RV strains isolated in Northern (Ferrara) and Southern (Galatina-LE) Italy. During 2007-2008, 115 RV-positive stool samples were collected from children with diarrhea admitted to the hospitals of Ferrara and Galatina. The specimens were genotyped for VP7 (G-type) and VP4 (P-type) gene by reverse transcription (RT) and multiplex polymerase chain reaction (PCR). A subset of 21 RV strains was randomly selected and characterized by sequence analysis of the VP7 genes. In total, seven G/P combinations (G1P[8], G2P[4], G4P[8], G9P[8], G2P[8], G1P[9], and G2P[10]) were identified. Phylogenetic comparison of the VP7 encoding gene of selected strains showed that there was similarity among RV strains circulating in Northern and Southern Italy. The observation of nucleotide sequence diversity contributes to a better understanding of RV spreading and helps to characterize the various antigenic shifts that could have an impact on vaccine effectiveness. [ABSTRACT FROM AUTHOR]

A study was undertaken to determine the prevalence of obesity in dogs examined by veterinary practices across Australia, and to determine the risk factors involved; 1700 practices were asked to complete a veterinarian opinion survey, and of the 428 practices that responded, 178 were selected to complete an RSPCA Australia Pet Obesity Questionnaire, together with additional practices selected by Australian State and Territory RSPCA societies. This questionnaire was sent to a total of 209 practices which were asked to record details of eligible dogs, and the reason why they had been examined during the previous month. Fifty-two (24.9 per cent) of the practices responded and provided data on 2661 dogs, of which 892 (33.5 per cent) were overweight and 201 (7.6 per cent) were obese. A further 112 dogs (4.2 per cent) were classified as thin or very thin, but these were excluded from subsequent analyses. Of the remaining 2549 dogs, approximately half were female and 1905 (74.7 per cent) were neutered. The dogs' weight category was influenced by several factors. Breed influenced the importance of sex and neutering as risk factors. The prevalence of overweight and obese dogs combined was 41 per cent; the prevalence increased with age up to about 10 years old, and then declined. Rural and semirural dogs were more at risk of obesity than urban and suburban dogs. [ABSTRACT FROM AUTHOR]

An abstract of the article "Reproducibility of IETA terms in describing endometrial pathology" by V. Chiappa and colleagues is presented.

An abstract of the article "Posterior cerebral artery pulsatility index in normal pregnancies" by A. Rossi, G. Filip, D. Visentin and others is presented.

Radiative feedback produced by stellar populations played a vital role in early structure formation. In particular, photons below the Lyman limit can escape the star-forming regions and produce a background ultraviolet (UV) flux, which consequently may influence the pristine halos far away from the radiation sources. These photons can quench the formation of molecular hydrogen by photodetachment of H–. In this study, we explore the impact of such UV radiation on fragmentation in massive primordial halos of a few times 107M☼. To accomplish this goal, we perform high resolution cosmological simulations for two distinct halos and vary the strength of the impinging background UV field in units of J21 assuming a blackbody radiation spectrum with a characteristic temperature of Trad = 104 K. We further make use of sink particles to follow the evolution for 10,000 yr after reaching the maximum refinement level. No vigorous fragmentation is observed in UV-illuminated halos while the accretion rate changes according to the thermal properties. Our findings show that a few 102-104 solar mass protostars are formed when halos are irradiated by J21 = 10-500 at z > 10 and suggest a strong relation between the strength of the UV flux and mass of a protostar. This mode of star formation is quite different from minihalos, as higher accretion rates of about 0.01-0.1 M☼ yr–1 are observed by the end of our simulations. The resulting massive stars are potential cradles for the formation of intermediate-mass black holes at earlier cosmic times and contribute to the formation of a global X-ray background. [ABSTRACT FROM AUTHOR]