21,922 research outputs found
GeMs/GSAOI observations of La Serena 94: an old and far open cluster inside the solar circle
Physical properties were derived for the candidate open cluster La Serena 94,
recently unveiled by the VVV collaboration. Thanks to the exquisite angular
resolution provided by GeMS/GSAOI, we could characterize this system in detail,
for the first time, with deep photometry in JHK - bands. Decontaminated
JHK diagrams reach about 5 mag below the cluster turnoff in H. The locus
of red clump giants in the colour - colour diagram, together with an extinction
law, was used to obtain an average extinction of . The
same stars were considered as standard - candles to derive the cluster
distance, kpc. Isochrones were matched to the cluster colour -
magnitude diagrams to determine its age, , and
metallicity, . A core radius of pc was
found by fitting King models to the radial density profile. By adding up the
visible stellar mass to an extrapolated mass function, the cluster mass was
estimated as M, consistent with an
integrated magnitude of and a tidal radius of
pc. The overall characteristics of La Serena 94 confirm that
it is an old open cluster located in the Crux spiral arm towards the fourth
Galactic quadrant and distant kpc from the Galactic centre. The
cluster distorted structure, mass segregation and age indicate that it is a
dynamically evolved stellar system.Comment: 16 pages, 24 figures, 2 Tables, accepted by MNRAS; corrected typo
Classification and biomarker selection in lower-grade glioma using robust sparse logistic regression applied to RNA-seq data
Funding Information: This work was supported by national funds through Fundação para a Ciência e a Tecnologia (FCT) with references CEECINST/00102/2018, UIDB/00297/2020 and UIDB/00297/2020 (NOVA MATH, Center for Mathematics and Applications), UIDB/04516/2020 (NOVA LINCS), and the research project “MONET – Multi-omic networks in gliomas” (PTDC/CCI-BIO/4180/2020). The results presented are based upon data generated by the TCGA Research Network: https://www.cancer. gov/tcga. Publisher Copyright: © Brazilian Journal of Biometrics.Effective diagnosis and treatment in cancer is a barrier for the development of personalized medicine, mostly due to tumor heterogeneity. In the particular case of gliomas, highly heterogeneous brain tumors at the histological, cellular and molecular levels, and exhibiting poor prognosis, the mechanisms behind tumor heterogeneity and progression remain poorly understood. The recent advances in biomedical high-throughput technologies have allowed the generation of large amounts of molecular information from the patients that combined with statistical and machine learning techniques can be used for the definition of glioma subtypes and targeted therapies, an invaluable contribution to disease understanding and effective management. In this work sparse and robust sparse logistic regression models with the elastic net penalty were applied to glioma RNA-seq data from The Cancer Genome Atlas (TCGA), to identify relevant tran-scriptomic features in the separation between lower-grade glioma (LGG) subtypes and identify putative outlying observations. In general, all classification models yielded good accuracies, selecting different sets of genes. Among the genes selected by the models, TXNDC12, TOMM20, PKIA, CARD8 and TAF12 have been reported as genes with relevant role in glioma development and progression. This highlights the suitability of the present approach to disclose relevant genes and fosters the biological validation of non-reported genes.publishersversionpublishe
Entropy Maximization in the Presence of Higher-Curvature Interactions
Within the context of the entropic principle, we consider the entropy of
supersymmetric black holes in N=2 supergravity theories in four dimensions with
higher-curvature interactions, and we discuss its maximization at points in
moduli space at which an excess of hypermultiplets becomes massless. We find
that the gravitational coupling function F^(1) enhances the maximization at
these points in moduli space. In principle, this enhancement may be modified by
the contribution from higher F^(g)-couplings. We show that this is indeed the
case for the resolved conifold by resorting to the non-perturbative expression
for the topological free energy.Comment: 22 pages, 8 figures, AMS-LaTe
How VR can boost inspiration and increase donations
One of the major challenges that non-profit organizations face is inspiring people to be concerned about
issues that seem geographically and emotionally distant. The aim of this study is to explore how Virtual
Reality (VR) can boost inspiration and encourage potential donors to contribute to nonprofit fundraisings. To
achieve this aim, a three group between-subjects experiment was conducted to examine how varying the
degree of immersiveness of a short documentary about a remote health issue influences user reported social
and spatial presence, inspiration, and donation intention. Findings reveal that perceived media richness
gradually increases the user's spatial presence. Then, the positive effect of social and spatial presence on
customer inspiration was tested and successfully verified. Finally, customer inspiration increases donation
intention.info:eu-repo/semantics/publishedVersio
Spatial patterns of mango malformation in irrigated areas of the brazilian semi-arid.
There are over 18.000 ha of irrigated mango in the São Francisco River Valley, and 90% of the fruit produced in this semi-arid region is exported to the european and american markets. With the expansion of the mango areas in the last decade, the intensity of malformation has been increasing, and there are many unresolved questions on the dynamics of the disease in the region, such as the role of the mango bud mite (Aceria mangiferae) or mechanical transmission in the dissemination of the disease. This study aimed to characterize the spatial patterns of mango malformation in commercial orchards, of the brazilian semi-arid
Exact solutions for supersymmetric stationary black hole composites
Four dimensional N=2 supergravity has regular, stationary, asymptotically
flat BPS solutions with intrinsic angular momentum, describing bound states of
separate extremal black holes with mutually nonlocal charges. Though the
existence and some properties of these solutions were established some time
ago, fully explicit analytic solutions were lacking thus far. In this note, we
fill this gap. We show in general that explicit solutions can be constructed
whenever an explicit formula is known in the theory at hand for the
Bekenstein-Hawking entropy of a single black hole as a function of its charges,
and illustrate this with some simple examples. We also give an example of
moduli-dependent black hole entropy.Comment: 13 pages, 1 figur
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