A Riemannian-Stein Kernel Method

This paper presents a theoretical analysis of numerical integration based on interpolation with a Stein kernel. In particular, the case of integrals with respect to a posterior distribution supported on a general Riemannian manifold is considered and the asymptotic convergence of the estimator in this context is established. Our results are considerably stronger than those previously reported, in that the optimal rate of convergence is established under a basic Sobolev-type assumption on the integrand. The theoretical results are empirically verified on $\mathbb{S}^2$

Stein Point Markov Chain Monte Carlo

An important task in machine learning and statistics is the approximation of a probability measure by an empirical measure supported on a discrete point set. Stein Points are a class of algorithms for this task, which proceed by sequentially minimising a Stein discrepancy between the empirical measure and the target and, hence, require the solution of a non-convex optimisation problem to obtain each new point. This paper removes the need to solve this optimisation problem by, instead, selecting each new point based on a Markov chain sample path. This significantly reduces the computational cost of Stein Points and leads to a suite of algorithms that are straightforward to implement. The new algorithms are illustrated on a set of challenging Bayesian inference problems, and rigorous theoretical guarantees of consistency are established

FLOW ANALYSIS AND MODELING OF THE LAKE ÁGUA PRETA: WATER SOURCE OF THE BELÉM METROPOLITAN AREA

The natural conditions of water resources can be modified with the unsustainable use of them. For example, in Belém, capital of Pará State, Água Preta Lake has a history of degradation jeopardize the drinking water supply in Belém. Thus, the main contribution of this work is to develop a study on modeling hydrodynamic study of Água Preta Lake. Such study is carried through the bathymetric of 2009 performed with an ADCP. The bathymetry and substrate data that composes the Lake and its boundary. The bathymetry data are used to construct the digital elevation model, with the coordinates x, y and z in UTM; while the composition of the substrate is used for the determination of the Manning coefficient. The coordinates x, y, z and Manning coefficient are used in the hydrodynamic model. This one is the classic model of Saint-Venant. In this case, a vertical integration is applied to the three-dimensional equations of Navier-Stokes for incompressible flow with outline conditions, of bottom and of liquid and solid surface, included. Thus, the problem becomes two-dimensional (2D) and the values obtained for velocities are medium in the vertical direction. The velocities are the input data for the many models, such as pollutant dispersion sediment transport and aquatic fauna and flora habitats. Thus, besides of hydrodynamic model explains the patterns of flow in the lake, it can be employed for the others models of the Lake Água Preta

Female Behaviour Drives Expression and Evolution of Gustatory Receptors in Butterflies

Secondary plant compounds are strong deterrents of insect oviposition and feeding, but may also be attractants for specialist herbivores. These insect-plant interactions are mediated by insect gustatory receptors (Grs) and olfactory receptors (Ors). An analysis of the reference genome of the butterfly Heliconius melpomene, which feeds on passion-flower vines (Passiflora spp.), together with whole-genome sequencing within the species and across the Heliconius phylogeny has permitted an unprecedented opportunity to study the patterns of gene duplication and copy-number variation (CNV) among these key sensory genes. We report in silico gene predictions of 73 Gr genes in the H. melpomene reference genome, including putative CO2, sugar, sugar alcohol, fructose, and bitter receptors. The majority of these Grs are the result of gene duplications since Heliconius shared a common ancestor with the monarch butterfly or the silkmoth. Among Grs but not Ors, CNVs are more common within species in those gene lineages that have also duplicated over this evolutionary time-scale, suggesting ongoing rapid gene family evolution. Deep sequencing (∼1 billion reads) of transcriptomes from proboscis and labial palps, antennae, and legs of adult H. melpomene males and females indicates that 67 of the predicted 73 Gr genes and 67 of the 70 predicted Or genes are expressed in these three tissues. Intriguingly, we find that one-third of all Grs show female-biased gene expression (n = 26) and nearly all of these (n = 21) are Heliconius-specific Grs. In fact, a significant excess of Grs that are expressed in female legs but not male legs are the result of recent gene duplication. This difference in Gr gene expression diversity between the sexes is accompanied by a striking sexual dimorphism in the abundance of gustatory sensilla on the forelegs of H. melpomene, suggesting that female oviposition behaviour drives the evolution of new gustatory receptors in butterfly genomes

Current Italian practices regarding the management of hyperbilirubinaemia in preterm infants.

AIM: To assess the current practices existing in Italy for the management of jaundice in preterm infants as preliminary achievement to a call for national guidelines and establishment of a kernicterus registry. METHODS: A questionnaire (in Supporting Information online) was sent to the 109 level III neonatal units in Italy to ascertain existing guidelines for total bilirubin monitoring and treatment of hyperbilirubinaemia in preterm infants and occurrence of kernicterus. RESULTS: There was a 61% (67/109) response rate. Eighty-five per cent of responding units had either written guidelines coming from different literature sources or locally developed. The monitoring of bilirubin varied greatly in timing before, during and after jaundice development. Phototherapy and exchange transfusion were given to 56.0 ± 21.0% and 0.2 ± 0.4% of admitted preterm infants in participating centres. Five cases of kernicterus in preterm infants and eleven cases in term infants were documented over the last 10 years. CONCLUSION: The management of hyperbilirubinaemia in preterm infants is not uniform in Italy and would benefit from shared national guidance together with establishment of a kernicterus registry to guide therapy

Myocardial antioxidant and oxidative stress changes due to sex hormones

The purpose of the present study was to examine myocardial antioxidant and oxidative stress changes in male and female rats in the presence of physiological sex hormone concentrations and after castration. Twenty-four 9-week-old Wistar rats were divided into four groups of 6 animals each: 1) sham-operated females, 2) castrated females, 3) sham-operated males, and 4) castrated males. When testosterone and estrogen levels were measured by radioimmunoassay, significant differences were observed between the castrated and control groups (both males and females), demonstrating the success of castration. Progesterone and catalase levels did not change in any group. Control male rats had higher levels of glutathione peroxidase (50%) and lower levels of superoxide dismutase (SOD, 14%) than females. Control females presented increased levels of SOD as compared to the other groups. After castration, SOD activity decreased by 29% in the female group and by 14% in the male group as compared to their respective controls. Lipid peroxidation (LPO) was assessed to evaluate oxidative damage to cardiac membranes by two different methods, i.e., TBARS and chemiluminescence. LPO was higher in male controls compared to female controls when evaluated by both methods, TBARS (360%) and chemiluminescence (46%). Castration induced a 200% increase in myocardial damage in females as determined by TBARS and a 20% increase as determined by chemiluminescence. In males, castration did not change LPO levels. These data suggest that estrogen may have an antioxidant role in heart muscle, while testosterone does not