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67 papers found.
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Evolutionary sequences of stellar models with new radiative opacities. VI.

We present a large grid of stellar evolutionary models with the initial chemical composition . These tracks are conceived to extend the grid of stellar models described in the previous papers of this series, and are computed with the new radiative opacities by Iglesias et al. (1992) and convective overshoot. The tracks span the range of initial masses from to , and extend from...

Calcium triplet synthesis

We present theoretical equivalent widths for the sum of the two strongest lines of the calcium triplet, CaT index, in the near-IR ( 8542, 8662 Å), using evolutionary synthesis techniques and the most recent models and observational data for this feature in individual stars. We compute the CaT index for Single Stellar Populations (instantaneous burst, standard Salpeter-type IMF...

Status of COMPASS RICH-1 Upgrade with MPGD-based Photon Detectors

A Set of new MPGD-based Photon Detectors is being built for the upgrade of COMPASS RICH-1. The detectors cover a total active area of 1.4 m2 and are based on a hybrid architecture consisting of two THGEM layers and a Micromegas. A CsI film on one THGEM acts as a reflective photocathode. The characteristics of the detector, the production of the components and their validation...

Status of COMPASS RICH-1 Upgrade with MPGD-based Photon Detectors

A Set of new MPGD-based Photon Detectors is being built for the upgrade of COMPASS RICH-1. The detectors cover a total active area of 1.4 m2 and are based on a hybrid architecture consisting of two THGEM layers and a Micromegas. A CsI film on one THGEM acts as a reflective photocathode. The characteristics of the detector, the production of the components and their validation...

Impact of metallicity on the evolution of young star clusters

We discuss the results of N-body simulations of intermediate-mass young star clusters (SCs) with three different metallicities (Z = 0.01, 0.1 and 1 Z⊙), including metallicity-dependent stellar evolution recipes and metallicity-dependent prescriptions for stellar winds and remnant formation. The initial half-mass relaxation time of the simulated young SCs (∼10 Myr) is comparable...

Extraction of high-quality DNA from ethanol-preserved tropical plant tissues

Background Proper conservation of plant samples, especially during remote field collection, is essential to assure quality of extracted DNA. Tropical plant species contain considerable amounts of secondary compounds, such as polysaccharides, phenols, and latex, which affect DNA quality during extraction. The suitability of ethanol (96% v/v) as a preservative solution prior to DNA...

A Spitzer-IRS view of early-type galaxies with cuspy/core nuclei and fast/slow rotation

Clusters of Galaxies: Probes of Cosmological Structure and Galaxy Evolution (Cambridge, New York: Cambridge University Press), 277 Nanni , A. , Bressan , A. Marigo , P. , & Girardi , L. 2013 , MNRAS, 434

Combined photometric and asteroseismic constraints on the properties of NGC 6791

. Hekker , S. Mathur , R.A. García , T.R. Bedding , H. Kjeldsen et al., ApJ 737 , L10 ( 2011 ) [5] A. Bressan , P. Marigo , L. Girardi , B. Salasnich , C. Dal Cero , S. Rubele , A. Nanni , MNRAS 427 , 127

Red Giant evolution and specific problems

In spite of the great effort made in the last decades to improve our understanding of stellar evolution, significant uncertainties still remain due to our poor knowledge of some complex physical processes that still require an empirical calibration, such as the efficiency of convective heat transport and interior mixing. Here we will review the impact of these uncertainties on...

Evaluating the effectiveness of a training program that builds teachers’ capability to identify and appropriately refer middle and high school students with mental health problems in Brazil: an exploratory study

Background In Brazil, like many countries, there has been a failure to identify mental health problems (MHP) in young people and refer them to appropriate care and support. The school environment provides an ideal setting to do this. Therefore, effective programs need to be developed to train teachers to identify and appropriately refer children with possible MHP. We aimed to...

Socioeconomic Disadvantage Moderates the Association between Peripheral Biomarkers and Childhood Psychopathology

Background Socioeconomic disadvantage (SED) has been consistently associated with early life mental health problems. SED has been shown to impact multiple biological systems, including the regulation of neurotrophic proteins, immune-inflammatory and oxidative stress markers, which, conversely, have been reported to be relevant to physiological and pathological neurodevelopment...

Effect of Chromosome Tethering on Nuclear Organization in Yeast

Interphase chromosomes in Saccharomyces cerevisiae are tethered to the nuclear envelope at their telomeres and to the spindle pole body (SPB) at their centromeres. Using a polymer model of yeast chromosomes that includes these interactions, we show theoretically that telomere attachment to the nuclear envelope is a major determinant of gene positioning within the nucleus only for...

The Salt Overly Sensitive (SOS) Pathway: Established and Emerging Roles

Soil salinity is a growing problem around the world with special relevance in farmlands. The ability to sense and respond to environmental stimuli is among the most fundamental processes that enable plants to survive. At the cellular level, the Salt Overly Sensitive (SOS) signaling pathway that comprises SOS3, SOS2, and SOS1 has been proposed to mediate cellular signaling under...

Ultra-luminous X-ray sources and remnants of massive metal-poor stars

Massive metal-poor stars might form massive stellar black holes (BHs), with mass 25 ≤mBH/M⊙≤ 80, via direct collapse. We derive the number of massive BHs (NBH) that are expected to form per galaxy through this mechanism. Such massive BHs might power most of the observed ultra-luminous X-ray sources (ULXs). We select a sample of 64 galaxies with X-ray coverage, measurements of the...

The Impact of Healthy Parenting As a Protective Factor for Posttraumatic Stress Disorder in Adulthood: A Case-Control Study

Background Early life social adversity can influence stress response mechanisms and is associated with anxious behaviour and reductions in callosal area later in life. Objective To evaluate the association between perceptions of parental bonding in childhood/adolescence, hypothalamic-pituitary-adrenal (HPA) axis response, and callosal structural integrity in adult victims of...

Starburst evolution: free–free absorption in the radio spectra of luminous IRAS galaxies

We describe radio observations at 244 and 610 MHz of a sample of 20 luminous and ultra-luminous IRAS galaxies. These are a subset of a sample of 31 objects that have well-measured radio spectra up to at least 23 GHz. The radio spectra of these objects below 1.4 GHz show a great variety of forms and are rarely a simple power-law extrapolation of the synchrotron spectra at higher...

PopStar I: evolutionary synthesis model description

We present new evolutionary synthesis models for simple stellar populations for a wide range of ages and metallicities. The models are based on the Padova isochrones. The core of the spectral library is provided by the medium resolution Lejeune et al. atmosphere models. These spectra are complemented by Non Local Thermodynamic Equilibrium (NLTE) atmosphere models for hot stars...

A Saccharomyces cerevisiae Assay System to Investigate Ligand/AdipoR1 Interactions That Lead to Cellular Signaling

Adiponectin is a mammalian hormone that exerts anti-diabetic, anti-cancer and cardioprotective effects through interaction with its major ubiquitously expressed plasma membrane localized receptors, AdipoR1 and AdipoR2. Here, we report a Saccharomyces cerevisiae based method for investigating agonist-AdipoR interactions that is amenable for high-throughput scale-up and can be used...

Epidemiology of Psychotropic Drug Use in Rio de Janeiro, Brazil: Gaps in Mental Illness Treatments

Objective Estimate the prevalence of psychotropic drugs use in the city of Rio de Janeiro, Brazil, and establish its relationship with the presence of mental disorders. Methods A probabilistic sample of non-institutionalized individuals, from the general population of Rio de Janeiro (n = 1208;turn out:81%), 15 years or older, who were interviewed using the Composite International...