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We study the interaction between dispersed and sticky information by assuming that firms receive private noisy signals about the state in an otherwise standard model of price setting with sticky information. We compute the unique equilibrium of the game induced by the firms’ pricing decisions and derive the resulting Phillips curve. The main effect of dispersion is to magnify the immediate impact of a given shock when the degree of stickiness is small. Its effect on persistence is minor: even when information is largely dispersed, a substantial amount of informational stickiness is needed to generate persistence in aggregate prices and inflation.
In this work, the stopping power of a partially ionized helium plasma due to its free and bound electrons is analyzed for an electron temperature and density in which local thermal equilibrium (LTE) or non-local thermal equilibrium (NLTE) regimes can be possible. In particular by means of collisional-radiative models, the average ionization of the plasma as well as the abundances of different helium species (HeI, HeII, and HeIII) are analyzed in both LTE and NLTE thermodynamic states. The influence of this ionization and of the different ion abundances on the stopping power of the helium plasma is shown to be quite significant. Finally, our theoretical model is compared with experimental results on slowing down of swift argon ions in helium plasma.
The luminosity function is a fundamental observable for characterising how galaxies form and evolve throughout the cosmic history. One key ingredient to derive this measurement from the number counts in a survey is the characterisation of the completeness and redshift selection functions for the observations. In this paper, we present GLACiAR, an open python tool available on GitHub to estimate the completeness and selection functions in galaxy surveys. The code is tailored for multiband imaging surveys aimed at searching for high-redshift galaxies through the Lyman-break technique, but it can be applied broadly. The code generates artificial galaxies that follow Sérsic profiles with different indexes and with customisable size, redshift, and spectral energy distribution properties, adds them to input images, and measures the recovery rate. To illustrate this new software tool, we apply it to quantify the completeness and redshift selection functions for J-dropouts sources (redshift z ~ 10 galaxies) in the Hubble Space Telescope Brightest of Reionizing Galaxies Survey. Our comparison with a previous completeness analysis on the same dataset shows overall agreement, but also highlights how different modelling assumptions for the artificial sources can impact completeness estimates.
The order Chiroptera is considered the second largest group of mammals in the world, hosting important zoonotic virus and bacteria. Bartonella and hemotropic mycoplasmas are bacteria that parasite different mammals’ species, including humans, causing different clinical manifestations. The present work aimed investigating the occurrence and assessing the phylogenetic positioning of Bartonella spp. and Mycoplasma spp. in neotropical bats sampled from Brazil. Between December 2015 and April 2016, 325 blood and/or tissues samples were collected from 162 bats comprising 19 different species sampled in five states of Brazil. Out of 322 bat samples collected, while 17 (5·28%) were positive to quantitative PCR for Bartonella spp. based on nuoG gene, 45 samples (13·97%) were positive to cPCR assays for hemoplasmas based on 16S rRNA gene. While seven sequences were obtained for Bartonella (nuoG) (n = 3), gltA (n = 2), rpoB (n = 1), ftsZ (n = 1), five 16S rRNA sequences were obtained for hemoplasmas. In the phylogenetic analysis, the Bartonella sequences clustered with Bartonella genotypes detected in bats sampled in Latin America countries. All five hemoplasmas sequences clustered together as a monophyletic group by Maximum Likelihood and Bayesian Inference analyses. The present work showed the first evidence of circulation of Bartonella spp. and hemoplasmas among bats in Brazil.
Partial hyperbolicity appeared in the 1960s as a natural generalization of hyperbolicity. In the last 20 years, there has been great activity in this area. Here we survey the state of the art in some related topics, focusing especially on partial hyperbolicity in dimension three. The reason for this is not only that it is the smallest dimension in which non-degenerate partial hyperbolicity can occur, but also that the topology of
-manifolds influences the dynamics in revealing ways.
The stellar occultation technique is a powerful tool to study distant small solar system bodies. Currently, around 2 500 trans-neptunian objects (TNOs) and Centaurs are known. With the astrometry from Gaia and large surveys like the Large Synoptic Survey Telescope (LSST), accurate predictions of occultation events will be available to tens of thousands of TNOs and Centaurs and boost the knowledge of the outer solar system.
The Dark Energy Survey is undertaking an observational programme imaging 1/4 of the southern hemisphere sky with unprecedented photometric accuracy. In the process of observing millions of faint stars and galaxies to constrain the parameters of the dark energy equation of state, the Dark Energy Survey will obtain pre-discovery images of the regions surrounding an estimated 100 gamma-ray bursts over 5 yr. Once gamma-ray bursts are detected by, e.g., the Swift satellite, the DES data will be extremely useful for follow-up observations by the transient astronomy community. We describe a recently-commissioned suite of software that listens continuously for automated notices of gamma-ray burst activity, collates information from archival DES data, and disseminates relevant data products back to the community in near-real-time. Of particular importance are the opportunities that non-public DES data provide for relative photometry of the optical counterparts of gamma-ray bursts, as well as for identifying key characteristics (e.g., photometric redshifts) of potential gamma-ray burst host galaxies. We provide the functional details of the DESAlert software, and its data products, and we show sample results from the application of DESAlert to numerous previously detected gamma-ray bursts, including the possible identification of several heretofore unknown gamma-ray burst hosts.
The stopping power of warm dense matter (WDM) is estimated by means of the individual contributions of free electrons and bound electrons existing in this special kind of matter, located between classical and degenerate plasmas. For free electrons, the dielectric formalism, well described in our studies, is used to estimate the free electron stopping power. For bound electrons, the mean excitation energy of ions is used. Excitation energies are obtained through atomic calculations of the whole atom or, shell by shell in order to estimate their stopping power. Influence of temperature and density is analyzed in case of an impinging projectile. This influence becomes important for low projectile velocities and is negligible for high ones. Using free and bound electron analysis, the stopping power of an extended WDM is inferred from a dynamical calculation of energy transferred from the projectile to the plasma, where the stopping range is calculated. Finally, this theoretical framework is used to study a typical plasma density profile of a WDM heated by lasers.
Boiling is the most common method of household water treatment in developing countries; however, it is not always effectively practised. We conducted a randomized controlled trial among 210 households to assess the effectiveness of water pasteurization and safe-storage interventions in reducing Escherichia coli contamination of household drinking water in a water-boiling population in rural Peru. Households were randomized to receive either a safe-storage container or a safe-storage container plus water pasteurization indicator or to a control group. During a 13-week follow-up period, households that received a safe-storage container and water pasteurization indicator did not have a significantly different prevalence of stored drinking-water contamination relative to the control group [prevalence ratio (PR) 1·18, 95% confidence interval (CI) 0·92–1·52]. Similarly, receipt of a safe-storage container alone had no effect on prevalence of contamination (PR 1·02, 95% CI 0·79–1·31). Although use of water pasteurization indicators and locally available storage containers did not increase the safety of household drinking water in this study, future research could illuminate factors that facilitate the effective use of these interventions to improve water quality and reduce the risk of waterborne disease in populations that boil drinking water.
In a 1-year survey at a university hospital we found that 20·6% (81/392) of patients with antibiotic associated diarrohea where positive for C. difficile. The most common PCR ribotypes were 012 (14·8%), 027 (12·3%), 046 (12·3%) and 014/020 (9·9). The incidence rate was 2·6 cases of C. difficile infection for every 1000 outpatients.
About 45 000 absolute and semi-absolute observations of right ascension of the FK4 stars were obtained during 1963–1972. The observations were made with the three instruments of the Cerro Calán Observatory jointly by Chilean and Soviet astronomers. As a result, systematic δαδ cosδ errors were found to exist in the FK4 catalogue. For the reduction of star observations according to the SRS program, it is necessary to derive the system of the δα corrections for the FK4.
This article examines a potential ‘throne–mat’ kenning in the Middle Formative period Olmec writing on the Cascajal Block, an incised serpentine slab dated to c. 900 bc. It is suggested that signs on the Cascajal Block are divorced from the Formative period representational canons in which they are usually contextualized. The organization of signs on the Cascajal Block thus de-emphasizes the connection between a depicted object and its iconographic frame of reference. Instead, the signs are recontextualized within a linguistic framework wherein they leverage their iconicity to denote a word, rather than functioning primarily as an iconographic element within a pictorial composition. It is argued that the throne–mat kenning explored here is one instance of such abstraction from ‘normative’ iconographic contexts and therefore offers potentially significant insights into the origin and development of writing in Mesoamerica.
It has been demonstrated that persistent organic pollutants (POPs) can affect the immune system of mammals and birds. In this study, the concentration of different POPs and leukocytes in blood samples from three chinstrap penguin (Pygoscelis antarctica) populations was analysed in order to assess the impact on haematological parameters. Using blood sample smears, basophils, eosinophils, heterophils, lymphocytes and monocytes were quantified. Mature and immature red blood cells were counted and cell alterations in both white and red blood cells were analysed. At the same time, whole blood was analysed for POPs. The results showed that contaminants, such as dichlorodiphenyltrichloroethane and its metabolites (ΣDDT), as well as polychlorinated biphenyls (ΣPCB), had significant correlations to eosinophils, lymphocytes and heterophils. This indicates possible immunohaematological alterations derived from exposure to such contaminants. Cytological alterations were also observed, such as cytotoxic granules, toxic heterophils, and atypical and granulated lymphocytes, which would demonstrate that these seabirds are being exposed to stress agents that could be producing some alterations at a leukocytary cellular level.
POLICAN is a near-infrared (J, H, K) imaging polarimeter developed for the Cananea near infrared camera (CANICA) at the 2.1m telescope of the Guillermo Haro Astrophysical Observatory (OAGH) located at Cananea, Sonora, México. The camera has a 1024 x 1024 HgCdTe detector (HAWAII array) with a plate scale of 0.32 arcsec/pixel providing a field of view of 5.5 x 5.5 arcmin. POLICAN is mounted externally to CANICA for narrow-field (f/12) linear polarimetric observations. It consists of a rotating super achromatic (1-2.7μm) half waveplate and a fixed wire-grid polarizer as the analyzer. The light is modulated by setting the half waveplate at different angles (0○, 22.5○, 45○, 67.5○) and linear combinations of the Stokes parameters (I, Q and U) are obtained. Image reduction and removal of instrumental polarization consist of dark noise subtraction, polarimetric flat fielding and background sky subtraction. Polarimetric calibration is performed by observing polarization standards available in the literature. The astrometry correction is performed by matching common stars with the Two Micron All Sky Survey. POLICAN's bright and limiting magnitudes are approximately 6th and 16th magnitude, which correspond to saturation and photon noise, respectively. POLICAN currently achieves a polarimetric accuracy about 3.0% and polarization angle uncertainties within 3○. Preliminary observations of star forming regions are being carried out in order to study their magnetic field properties.
The study of the evolution of organic matter subjected to space conditions, and more specifically to Solar photons in the vacuum ultraviolet range (120–200 nm) has been undertaken in low-Earth orbit since the 1990s, and implemented on various space platforms. This paper describes a photochemistry experiment called AMINO, conducted during 22 months between 2009 and 2011 on the EXPOSE-R ESA facility, outside the International Space Station. Samples with relevance to astrobiology (connected to comets, carbonaceous meteorites and micrometeorites, the atmosphere of Titan and RNA world hypothesis) have been selected and exposed to space environment. They have been analysed after return to the Earth. This paper is not discussing the results of the experiment, but rather gives a general overview of the project, the details of the hardware used, its configuration and recent developments to enable long-duration exposure of gaseous samples in tight closed cells enabling for the first time to derive quantitative results from gaseous phase samples exposed in space.
According to the work of Dennis Sullivan [A counterexample to the periodic orbit conjecture. Publ. Math. Inst. Hautes Études Sci.46 (1976), 5–14], there exists a smooth flow on the five-sphere all of whose orbits are periodic, although there is no uniform bound on their periods. The question addressed in this article is whether these type of examples can occur in the partially hyperbolic context. That is, does there exist a partially hyperbolic diffeomorphism of a compact manifold such that all the leaves of its center foliation are compact but there is no uniform bound for their volumes? We develop tools to attack the previous question and show that it has a negative answer provided that all periodic leaves have finite holonomy.
The aim of this study was to determine the effect of single layer centrifugation (SLC) using Androcoll-E-Large on donkey sperm quality parameters after 24 h of cool-storage. Ejaculates were collected from Andalusian donkeys and then cooled at 5°C. SLC was carried out after 24 h of cool-storage using Androcoll-E-Large. In the first experiment, all sperm parameters assessed (total and progressive sperm motility, viability, sperm morphology and sperm kinematics VCL, VSL, VAP, LIN, STR, WOB, ALH and BCF) were statistically compared between semen samples processed or not with Androcoll-E-Large. Significant differences (P<0.05) were found between SLC-selected and unselected semen samples for all parameters assessed, obtaining better results after SLC. In the second experiment, semen samples were classified in two groups according to their sperm progressive motility (PM) before SLC. Then, the increments obtained in semen quality parameters after SLC were compared between groups. No significant differences were found between groups, indicating that SLC improved the sperm quality parameters of entire set of semen samples processed with independence to their original PM. In conclusion, SLC with Androcoll-E-Large can be used in donkeys, increasing the sperm quality of cooled-stored donkey semen doses after 24 h of cool storage.
CARMENES (Calar Alto high-Resolution search for M dwarfs with Exo-earths with Near-infrared and optical Echelle Spectrographs) will conduct a radial-velocity survey of ~ 300 M dwarfs with the 3.5m telescope at the Calar Alto Observatory. The CARMENES instrument is currently under construction; it consists of two independent échelle spectrographs, which together cover the wavelength range 0.55 – 1.7μm at a spectral resolution of R = 82,000. The spectrographs and the fiber input are designed with a goal of 1m/s radial velocity precision using simultaneous calibration with emission-line lamps.