374 research outputs found
Level-of-Detail Triangle Strips for Deforming Meshes
Applications such as video games or movies often contain deforming
meshes. The most-commonly used representation of these types of meshes consists in dense polygonal models. Such a large amount of
geometry can be efficiently managed by applying level-of-detail techniques
and specific solutions have been developed in this field. However,
these solutions do not offer a high performance in real-time applications.
We thus introduce a multiresolution scheme for deforming meshes.
It enables us to obtain different approximations over all the frames of
an animation. Moreover, we provide an efficient connectivity coding by means of triangle strips as well as a flexible framework adapted to the GPU pipeline. Our approach enables real-time performance and, at the same time, provides accurate approximations
Good practices for a literature survey are not followed by authors while preparing scientific manuscripts
The number of citations received by authors in scientific journals has become
a major parameter to assess individual researchers and the journals themselves
through the impact factor. A fair assessment therefore requires that the
criteria for selecting references in a given manuscript should be unbiased with
respect to the authors or the journals cited. In this paper, we advocate that
authors should follow two mandatory principles to select papers (later
reflected in the list of references) while studying the literature for a given
research: i) consider similarity of content with the topics investigated, lest
very related work should be reproduced or ignored; ii) perform a systematic
search over the network of citations including seminal or very related papers.
We use formalisms of complex networks for two datasets of papers from the arXiv
repository to show that neither of these two criteria is fulfilled in practice
Decision Tree Classifiers for Star/Galaxy Separation
We study the star/galaxy classification efficiency of 13 different decision
tree algorithms applied to photometric objects in the Sloan Digital Sky Survey
Data Release Seven (SDSS DR7). Each algorithm is defined by a set of parameters
which, when varied, produce different final classification trees. We
extensively explore the parameter space of each algorithm, using the set of
SDSS objects with spectroscopic data as the training set. The
efficiency of star-galaxy separation is measured using the completeness
function. We find that the Functional Tree algorithm (FT) yields the best
results as measured by the mean completeness in two magnitude intervals: () and (). We compare the performance of the
tree generated with the optimal FT configuration to the classifications
provided by the SDSS parametric classifier, 2DPHOT and Ball et al. (2006). We
find that our FT classifier is comparable or better in completeness over the
full magnitude range , with much lower contamination than all but
the Ball et al. classifier. At the faintest magnitudes (), our classifier
is the only one able to maintain high completeness (80%) while still
achieving low contamination (). Finally, we apply our FT classifier
to separate stars from galaxies in the full set of SDSS
photometric objects in the magnitude range .Comment: Submitted to A
Seasonal changes in patterns of gene expression in avian song control brain regions.
This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Photoperiod and hormonal cues drive dramatic seasonal changes in structure and function of the avian song control system. Little is known, however, about the patterns of gene expression associated with seasonal changes. Here we address this issue by altering the hormonal and photoperiodic conditions in seasonally-breeding Gambel's white-crowned sparrows and extracting RNA from the telencephalic song control nuclei HVC and RA across multiple time points that capture different stages of growth and regression. We chose HVC and RA because while both nuclei change in volume across seasons, the cellular mechanisms underlying these changes differ. We thus hypothesized that different genes would be expressed between HVC and RA. We tested this by using the extracted RNA to perform a cDNA microarray hybridization developed by the SoNG initiative. We then validated these results using qRT-PCR. We found that 363 genes varied by more than 1.5 fold (>log(2) 0.585) in expression in HVC and/or RA. Supporting our hypothesis, only 59 of these 363 genes were found to vary in both nuclei, while 132 gene expression changes were HVC specific and 172 were RA specific. We then assigned many of these genes to functional categories relevant to the different mechanisms underlying seasonal change in HVC and RA, including neurogenesis, apoptosis, cell growth, dendrite arborization and axonal growth, angiogenesis, endocrinology, growth factors, and electrophysiology. This revealed categorical differences in the kinds of genes regulated in HVC and RA. These results show that different molecular programs underlie seasonal changes in HVC and RA, and that gene expression is time specific across different reproductive conditions. Our results provide insights into the complex molecular pathways that underlie adult neural plasticity
The Brazilian Developments on the Regional Atmospheric Modeling System (BRAMS 5.2): An Integrated Environmental Model Tuned for Tropical Areas
We present a new version of the Brazilian developments on the Regional Atmospheric Modeling System where different previous versions for weather, chemistry and carbon cycle were unified in a single integrated software system. The new version also has a new set of state-of-the-art physical parameterizations and greater computational parallel and memory usage efficiency. Together with the description of the main features are examples of the quality of the transport scheme for scalars, radiative fluxes on surface and model simulation of rainfall systems over South America in different spatial resolutions using a scale-aware convective parameterization. Besides, the simulation of the diurnal cycle of the convection and carbon dioxide concentration over the Amazon Basin, as well as carbon dioxide fluxes from biogenic processes over a large portion of South America are shown. Atmospheric chemistry examples present model performance in simulating near-surface carbon monoxide and ozone in Amazon Basin and Rio de Janeiro megacity. For tracer transport and dispersion, it is demonstrated the model capabilities to simulate the volcanic ash 3-d redistribution associated with the eruption of a Chilean volcano. Then, the gain of computational efficiency is described with some details. BRAMS has been applied for research and operational forecasting mainly in South America. Model results from the operational weather forecast of BRAMS on 5 km grid spacing in the Center for Weather Forecasting and Climate Studies, INPE/Brazil, since 2013 are used to quantify the model skill of near surface variables and rainfall. The scores show the reliability of BRAMS for the tropical and subtropical areas of South America. Requirements for keeping this modeling system competitive regarding on its functionalities and skills are discussed. At last, we highlight the relevant contribution of this work on the building up of a South American community of model developers
The Type and the Position of HNF1A Mutation Modulate Age at Diagnosis of Diabetes in Patients with Maturity-Onset Diabetes of the Young (MODY)-3
OBJECTIVE—The clinical expression of maturity-onset diabetes of the young (MODY)-3 is highly variable. This may be due to environmental and/or genetic factors, including molecular characteristics of the hepatocyte nuclear factor 1-α (HNF1A) gene mutation.
RESEARCH DESIGN AND METHODS—We analyzed the mutations identified in 356 unrelated MODY3 patients, including 118 novel mutations, and searched for correlations between the genotype and age at diagnosis of diabetes.
RESULTS—Missense mutations prevailed in the dimerization and DNA-binding domains (74%), while truncating mutations were predominant in the transactivation domain (62%). The majority (83%) of the mutations were located in exons 1- 6, thus affecting the three HNF1A isoforms. Age at diagnosis of diabetes was lower in patients with truncating mutations than in those with missense mutations (18 vs. 22 years, P = 0.005). Missense mutations affecting the dimerization/DNA-binding domains were associated with a lower age at diagnosis than those affecting the transactivation domain (20 vs. 30 years, P = 10−4). Patients with missense mutations affecting the three isoforms were younger at diagnosis than those with missense mutations involving one or two isoforms (P = 0.03).
CONCLUSIONS—These data show that part of the variability of the clinical expression in MODY3 patients may be explained by the type and the location of HNF1A mutations. These findings should be considered in studies for the search of additional modifier genetic factors
Produção integrada de uva para processamento - vinho e suco: caderno de campo.
O presente Documento de Acompanhamento serve de base para que o produtor, devidamente acompanhado pelo técnico ou consultor da PIUP garanta a rastreabilidade do Sistema, pois permite registrar as principais características do vinhedo e todas as atividades relacionadas ao sistema de produção, aplicadas em cada parcela. Esses registros são essenciais para o estabelecimento de um sistema de produção de uvas para processamento pautado pela segurança alimentar, ambiental e do produtor.bitstream/item/138943/1/Paulo-Roberto.pd
Language and scientific communication: The case of the reprint request
This paper reports on a study of Reprint Requests (RRs). It is estimated that tens of millions of RRs are mailed each year, most being triggered by Current Contents . A sample of RRs generated by three papers, plus a questionnaire-survey of the requesters for one paper, form the basis of this study into language use patterns in the RR genre. English is ubiquitous, German and French infrequent, Russian and Spanish rare. This language data is significant because it provides unit-level language decision making (as opposed to that at other levels). Various applications of RR research are discussed, including its relevance to the issue of “Third World Science”.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/43668/1/11192_2005_Article_BF02017177.pd
- …