3,657 research outputs found
Personality, Parenting Style, and Academic Cognitions: The Effects of Authoritarian Parenting Style on Personality Traits and Behaviors
Presented is an analysis of self-esteem as a moderator of the effect authoritarian parenting on personality trait and behavior development
Nod1 signaling overcomes resistance of S. pneumoniae to opsonophagocytic killing
Airway infection by the Gram-positive pathogen Streptococcus pneumoniae (Sp) leads to recruitment of neutrophils but
limited bacterial killing by these cells. Co-colonization by Sp and a Gram-negative species, Haemophilus influenzae (Hi),
provides sufficient stimulus to induce neutrophil and complement-mediated clearance of Sp from the mucosal surface
in a murine model. Products from Hi, but not Sp, also promote killing of Sp by ex vivo neutrophil-enriched peritoneal
exudate cells. Here we identify the stimulus from Hi as its peptidoglycan. Enhancement of opsonophagocytic killing
was facilitated by signaling through nucleotide-binding oligomerization domain-1 (Nod1), which is involved in
recognition of γ-D-glutamyl-meso-diaminopimelic acid (meso-DAP) contained in cell walls of Hi but not Sp. Neutrophils
from mice treated with Hi or compounds containing meso-DAP, including synthetic peptidoglycan fragments, showed
increased Sp killing in a Nod1-dependent manner. Moreover, Nod1-/- mice showed reduced Hi-induced clearance of Sp
during co-colonization. These observations offer insight into mechanisms of microbial competition and demonstrate
the importance of Nod1 in neutrophil-mediated clearance of bacteria in vivo
Imprints of radial migration on the Milky Way’s metallicity distribution functions
Recent analysis of the SDSS-III/Apache Point Observatory Galactic Evolution Experiment (APOGEE) Data Release 12 stellar catalog has revealed that the Milky Way’s (MW) metallicity distribution function (MDF) changes shape as a function of radius, transitioning from being negatively skewed at small Galactocentric radii to positively skewed at large Galactocentric radii. Using a high-resolution, N-body+SPH simulation, we show that the changing skewness arises from radial migration—metal-rich stars form in the inner disk and subsequently migrate to the metal-poorer outer disk. These migrated stars represent a large fraction (>50%) of the stars in the outer disk; they populate the high-metallicity tail of the MDFs and are, in general, more metal-rich than the surrounding outer disk gas. The simulation also reproduces another surprising APOGEE result: the spatially invariant high-[α/Fe] MDFs. This arises in the simulation from the migration of a population formed within a narrow range of radii (3.2 ±1.2 kpc) and time (8.8 ± 0.6 Gyr ago), rather than from spatially extended star formation in a homogeneous medium at early times. These results point toward the crucial role radial migration has played in shaping our MW
Georgia Academy of Science, University of North Georgia, March 15th-16th, 2019
The annual meeting of the Georgia Academy of Science took place March 15–16, 2019, at the University of North Georgia in Oakwood. The keynote speaker was Dr. Marguerite Madden, Professor in the University of Georgia\u27s Department of Geography and Director of the Center for Geospatial Research. Her presentation was entitled Geospatial Technologies and Augmented Reality Spark Excitement in Science Education, Research and Outreach. Additional presentations were provided by members of the Academy who represented the following sections: I. Biological Sciences, II. Chemistry, III. Earth & Atmospheric Sciences, IV. Physics, Mathematics, Computer Science, Engineering, & Technology, V. Biomedical Sciences, VI. Philosophy & History of Science, VII. Science Education, and VIII. Anthropology
The origin of type I profiles in cluster lenticulars: an interplay between ram pressure stripping and tidally induced spiral migration
Using N-body + smooth particle hydrodynamics simulations of galaxies falling into a cluster, we study the evolution of their radial density profiles. When evolved in isolation, galaxies develop a type II (down-bending) profile. In the cluster, the evolution of the profile depends on the minimum cluster-centric radius the galaxy reaches, which controls the degree of ram pressure stripping. If the galaxy falls to ∼50 per cent of the virial radius, then the profile remains type II, but if the galaxy reaches down to ∼20 per cent of the virial radius, the break weakens and the profile becomes more type I like. The velocity dispersions are only slightly increased in the cluster simulations compared with the isolated galaxy; random motion therefore cannot be responsible for redistributing material sufficiently to cause the change in the profile type. Instead, we find that the joint action of radial migration driven by tidally induced spirals and the outside-in quenching of star formation due to ram pressure stripping alters the density profile. As a result, this model predicts a flattening of the age profiles amongst cluster lenticulars with type I profiles, which can be observationally tested
Direct health costs of inflammatory polyarthritis 10 years after disease onset:Results from the Norfolk Arthritis Register
Objectives: To explore the change in direct medical costs associated with inflammatory polyarthritis (IP) 10 to 15 years after its onset. Methods: Patients from the Norfolk Arthritis Register who had previously participated in a health economic study in 1999 were traced 10 years later and invited to participate in a further prospective questionnaire-based study. The study was designed to identify direct medical costs and changes in health status over a 6-month period using previously validated questionnaires as the primary source of data. Results: A representative sample of 101 patients with IP from the 1999 cohort provided complete data over the 6-month period. The mean disease duration was 14 years (SD 2.1, median 13.6, interquartile range 12.6–15.4). The mean direct medical cost per patient over the 6-month period was £1496 for IP (inflated for 2013 prices). This compared with £582 (95% CI £355–£964) inflated to 2013 prices per patient with IP 10 years earlier in their disease. The increased cost was largely associated with the use of biologics in the rheumatoid arthritis subgroup of patients (51% of total costs incurred). Other direct cost components included primary care costs (11%), hospital outpatient (19%), day care (12%), and inpatient stay (4%). Conclusion: The direct healthcare costs associated with IP have more than doubled with increasing disease duration, largely as a result of the use of biologics. The results showed a shift in the direct health costs from inpatient to outpatient service use
Quantifying the Origin and Distribution of Intracluster Light in a Fornax-like Cluster
Using a cosmological -body simulation, we investigate the origin and
distribution of stars in the intracluster light (ICL) of a Fornax-like cluster.
In a dark matter only simulation we identify a halo which, at , has and , and replace infalling
subhalos with models that include spheroid and disc components. As they fall
into the cluster, the stars in some of these galaxies are stripped from their
hosts, and form the ICL. We consider the separate contributions to the ICL from
stars which originate in the haloes and the discs of the galaxies. We find that
disc ICL stars are more centrally concentrated than halo ICL stars. The
majority of the disc ICL stars are associated with one initially disc-dominated
galaxy that falls to the centre of the cluster and is heavily disrupted,
producing part of the cD galaxy. At radial distances greater than 200kpc, well
beyond the stellar envelope of the cD galaxy, stars formerly from the stellar
haloes of galaxies dominate the ICL. Therefore at large distances, the ICL
population is dominated by older stars.Comment: Paper published as MNRAS , 2017, 467, 4501 This version corrects a
small typo in the authors fiel
Constraints on primordial gravitational waves from the cosmic microwave background
Searches for primordial gravitational waves have resulted in constraints in a large frequency range from a variety of sources. The standard Cosmic Microwave Background (CMB) technique is to parameterise the tensor power spectrum in terms of the tensor-to-scalar ratio, r, and spectral index, nt, and constrain these using measurements of the temperature and polarization power spectra. Another method, applicable to modes well inside the cosmological horizon at recombination, uses the shortwave approximation, under which gravitational waves behave as an effective neutrino species. In this paper we give model-independent CMB constraints on the energy density of gravitational waves, Ωgw h2, for the entire range of observable frequencies. On large scales, f 10−16 Hz, we reconstruct the initial tensor power spectrum in logarithmic frequency bins, finding maximal sensitivity for scales close to the horizon size at recombination. On small scales, f 10−15 Hz, we use the shortwave approximation, finding Ωgw h2 < 1.7 ×10−6 for adiabatic initial conditions and Ωgw h2 < 2.9 ×10−7 for homogeneous initial conditions (both 2σ upper limits). For scales close to the horizon size at recombination, we use second-order perturbation theory to calculate the back-reaction from gravitational waves, finding Ωgw h2 < 8.4 ×10−7, in the absence of neutrino anisotropic stress and Ωgw h2 < 8.6 ×10−7 when including neutrino anisotropic stress. These constraints are valid for 10−15 Hz f 3 × 10−16 Hz
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