33,589 research outputs found
Axioms for consensus functions on the n-cube
An elementary general result is proved that allows for simple
characterizations of well-known location/consensus functions (median, mean and
center) on the n-cube. In addition, alternate new characterizations are given
for the median and anti-median functions on the n-cube.Comment: 12 page
Made-to-Measure models of the Galactic Box/Peanut bulge: stellar and total mass in the bulge region
We construct dynamical models of the Milky Way's Box/Peanut (B/P) bulge,
using the recently measured 3D density of Red Clump Giants (RCGs) as well as
kinematic data from the BRAVA survey. We match these data using the NMAGIC
Made-to-Measure method, starting with N-body models for barred discs in
different dark matter haloes. We determine the total mass in the bulge volume
of the RCGs measurement (+-2.2 x +- 1.4 x +- 1.2 kpc) with unprecedented
accuracy and robustness to be 1.84 +- 0.07 x10^10 Msun. The stellar mass in
this volume varies between 1.25-1.6 x10^10 Msun, depending on the amount of
dark matter in the bulge. We evaluate the mass-to-light and mass-to-clump
ratios in the bulge and compare them to theoretical predictions from population
synthesis models. We find a mass-to-light ratio in the K-band in the range
0.8-1.1. The models are consistent with a Kroupa or Chabrier IMF, but a
Salpeter IMF is ruled out for stellar ages of 10 Gyr. To match predictions from
the Zoccali IMF derived from the bulge stellar luminosity function requires
about 40% or 0.7 x10^10 Msun dark matter in the bulge region. The BRAVA data
together with the RCGs 3D density imply a low pattern speed for the Galactic
B/P bulge of 25-30 km.s-1.kpc-1. This would place the Galaxy among the slow
rotators (R >= 1.5). Finally, we show that the Milky Way's B/P bulge has an
off-centred X structure, and that the stellar mass involved in the peanut shape
accounts for at least 20% of the stellar mass of the bulge, significantly
larger than previously thought.Comment: Accepted for publication in MNRA
CrossCarry: An R package for the analysis of data from a crossover design with GEE
Experimental crossover designs are widely used in medicine, agriculture, and
other areas of the biological sciences. Due to the characteristics of the
crossover design, each experimental unit has longitudinal observations and the
presence of drag effects on the response variable. There is no package in {R}
that clearly models data from crossover designs. The {CrossCarry} package
presented in this paper allows testing any crossover design as long as the
observed response variable belongs to the exponential family, regardless of
whether or not there is a washout period. It also allows modeling repeated
measurements within each period and extends the correlation structures used in
the generalized estimating equations. The family of correlation structures is
built that takes into account the particularities of the design, that is, the
correlation between and within the periods. It also includes a parametric
component for modeling treatment effects and a non-parametric component for
modeling time effects and carry-over effects. The non-parametric component is
estimated from splines inserted into the generalized estimation equations
Caracterização de bactérias e fungos envolvidos na degradação de sulfentrazona em solos.
bitstream/CNPMA/8148/1/boletim_51.pd
Detecção de condições de estresse em plantas e potencial para "screening" em milho através da fluorescência da clorofila.
Influence of anthropometry and body composition in climbing ability
INTRODUCTION: Climbing has become a popular, competitive and recreational sport. It requires, principally, skilled technique and high muscle strength. Therefore, it has been necessary to implement formal studies about the training of this discipline. Investigations have been performed some studies to demonstrate that the improvement of climbing can be explained with anthropometric and physiological variables. PURPOSE: The purpose of this study was evaluate the main variables that affect the performance of the climbing, namely, anthropometry, body composition and climbing level. METHODS: Eighteen climbers, ranged 22 - 40 years old and V2-V7 of climbing ability (according Hueco Tanks scale), were volunteered to participate. Measurements of anthropometric characteristics and body composition including height, arm spam, forearm maximum, midstylion-dactilion, lean arm mass, body mass index (BMI), skeletal muscle mass, body fat mass, visceral fat, were performed. All variables were evaluated by using a combination of a principal component analysis (PCA) with a cluster analysis. RESULTS: When the analysis was performed in both anthropometry (skeletal muscle mass, lean arm mass and forearm maximum) and body composition (BMI, body fat mass and visceral fat) groups of variables, the results showed an 86% of the variance. The anthropometry variables showed correlation with 60% of the total variance. Concretely, the higher climbing level athletes (V5-V7) showed a higher lean body mass and arm muscle mass than the lower climbing levels athletes (V0-V4). On the other hand, the last group showed higher body fat mass and visceral fat mass with respect to the V5-V7 climbing athletes. CONCLUSION: The data of the present study showed a clear tendency on the variables, both body composition and anthropometry, in terms of the climbing level. However, these results are not completely conclusive. We suggest necessary to improve the performance of the measurements in future studies
Caracterização de bactérias e fungos envolvidos na degradação de sulfentrazona em solos.
Uma vez que microrganismos presentes nos solos são capazes de degradar e mineralizar agrotóxicos, é possível fazer a biorremediação de sítios contaminados, empregando-se microrganismos previamente selecionados. Logo, o isolamento, a caracterização e a identificação de microrganismos, com capacidade para metabolizar compostos potencialmente tóxicos, é de suma importância para a biorremediação. Não há registros na literatura sobre a identificação de microrganismos que degradem a sulfentrazona. Esse herbicida destaca-se como um dos mais utilizados nas principais culturas do Brasil. Assim, é necessário determinar quais os microrganismos que podem estar envolvidos em sua dissipação. Para isso solos sem histórico da aplicação do herbicida foram suplementados com sulfentrazona como única fonte de carbono e energia. Após 255 dias de incubação foram retiradas amostras para o isolamento e identificação dos microrganismos resistentes e ou degradadores do herbicida. Após a diluição em série, alíquotas foram plaqueadas em meio de cultura mínimo suplementado com o herbicida. As colônias que cresceram foram isoladas e selecionadas em meio de cultura mínimo líquido suplementado com concentrações crescentes de sulfentrazona. Após três repicagens os microrganismos foram plaqueados e purificados em meio mínimo sólido. As bactérias e actinomicetos foram identificados pelo perfil de ácidos graxos da membrana celular. Os fungos foram isolados e identificados com o auxílio de microscopia eletrônica de varredura e o uso de manual de identificação. As bactérias degradadoras de sulfentrazona foram identificadas como Nocardia brasiliensis, Acinetobacter calcoaceticus, Rhizobium radiobacter, Ralstonia pickettii e Methylobacterium radiotolerans. Os fungos isolados e identificados como degradadores deste herbicida pertencem aos gêneros Cladosporium sp., Eupenicillium sp., Paecilomyces sp., Penicillium sp., Chrysosporium sp. e Metarrhizium sp
Fluorescent Ly-alpha emission from the high-redshift intergalactic medium
We combine a high-resolution hydro-simulation of the LambdaCDM cosmology with
two radiative transfer schemes (for continuum and line radiation) to predict
the properties, spectra and spatial distribution of fluorescent Ly-alpha
emission at z~3. We focus on line radiation produced by recombinations in the
dense intergalactic medium ionized by UV photons. In particular, we consider
both a uniform background and the case where gas clouds are illuminated by a
nearby quasar. We find that the emission from optically thick regions is
substantially less than predicted from the widely used static, plane-parallel
model. The effects induced by a realistic velocity field and by the complex
geometric structure of the emitting regions are discussed in detail. We make
predictions for the expected brightness and size distributions of the
fluorescent sources.Our results account for recent null detections and can be
used to plan new observational campaigns both in the field (to measure the
intensity of the diffuse UV background) and in the proximity of bright quasars
(to understand the origin of high colum-density absorbers).Comment: 15 pages, 12 figures, accepted for publication in Ap
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