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Bayesian Modelling of Induced Responses and Neuronal Rhythms
Neural rhythms or oscillations are ubiquitous in neuroimaging data. These spectral responses have been linked to several cognitive processes; including working memory, attention, perceptual binding and neuronal coordination. In this paper, we show how Bayesian methods can be used to finesse the ill-posed problem of reconstructing-and explaining-oscillatory responses. We offer an overview of recent developments in this field, focusing on (i) the use of MEG data and Empirical Bayes to build hierarchical models for group analyses-and the identification of important sources of inter-subject variability and (ii) the construction of novel dynamic causal models of intralaminar recordings to explain layer-specific activity. We hope to show that electrophysiological measurements contain much more spatial information than is often thought: on the one hand, the dynamic causal modelling of non-invasive (low spatial resolution) electrophysiology can afford sub-millimetre (hyper-acute) resolution that is limited only by the (spatial) complexity of the underlying (dynamic causal) forward model. On the other hand, invasive microelectrode recordings (that penetrate different cortical layers) can reveal laminar-specific responses and elucidate hierarchical message passing and information processing within and between cortical regions at a macroscopic scale. In short, the careful and biophysically grounded modelling of sparse data enables one to characterise the neuronal architectures generating oscillations in a remarkable detail
Non-Commutative Correction to Thin Shell Collapse in Reissner Nordstrm Geometry
This paper investigates the polytropic matter shell collapse in the
non-commutative Reissner-Nordstrm geometry. Using the Israel
criteria, equation of motion for the polytropic matter shell is derived. In
order to explore the physical aspects of this equation, the most general
equation of state, , has been used for finite
and infinite values of . The effective potentials corresponding to the
equation of motion have been used to explain different states of the matter
shell collapse. The numerical solution of the equation of motion predicts
collapse as well as expansion depending on the choice of initial data. Further,
in order to include the non-commutative correction, we modify the matter
components and re-formulate the equation of motion as well as the corresponding
effective potentials by including non-commutative factor and charge parameter.
It is concluded that charge reduces the velocity of the expanding or collapsing
matter shell but does not bring the shell to static position. While the
non-commutative factor with generic matter favors the formation of black hole.Comment: 18 pages,17 figure
Mid-Term Results of EVAR in Severe Proximal Aneurysm Neck Angulation.
OBJECTIVE: To determine if mid-term outcome following endovascular aneurysm repair (EVAR) with the Endurant Stent Graft (Medtronic, Santa Rosa, CA, USA) is influenced by severe proximal neck angulation.
METHODS:
A retrospective case-control study was performed using data from a prospective multicenter database. All measurements were obtained using dedicated reconstruction software and center-lumen line reconstruction. Patients with neck length >15 mm, infrarenal angle (β) >75°, and/or suprarenal angle (α) >60°, or neck length >10 mm with β >60°, and/or α >45° were compared with a matched control group. Primary endpoint was primary clinical success. Secondary endpoints were freedom from rupture, type 1A endoleak, stent fractures, freedom from neck-related reinterventions, and aneurysm-related adverse events. Morphological neck variation over time was also assessed.
RESULTS:
Forty-five patients were included in the study group and were compared with a matched control group with 65 patients. Median follow-up time was 49.5 months (range 30.5-58.4). The 4-year primary clinical success estimates were 83% and 80% for the angulated and nonangulated groups (p = .42). Proximal neck angulation did not affect primary clinical success in a multivariate model (hazard ratio 1.56, 95% confidence interval 0.55-4.41). Groups did not differ significantly in regard to freedom from rupture (p = .79), freedom from type 1A endoleak (p = .79), freedom from neck-related adverse events (p = .68), and neck-related reinterventions (p = .68). Neck angle reduction was more pronounced in patients with severe proximal neck angulation (mean Δα -15.6°, mean Δβ -30.6°) than in the control group (mean Δα -0.39°, mean Δβ -5.9°) (p < .001).
CONCLUSION:
Mid-term outcomes following EVAR with the Endurant Stent Graft were not influenced by severe proximal neck angulation in our population. Despite the conformability of the device, moderate aortic neck remodeling was identified in the group of patients with angulated neck anatomy on the first computed tomography scan after implantation with no important further remodeling afterwards. No device integrity failures were encountered
Association of adverse oral health outcomes with socioeconomic inequalities and dental needs in Brazilian adolescents
This study aimed to explore the relations between adverse oral outcomes and socioeconomic, demographic, and self-rated oral health variables and to describe their distribution. Principal component analysis was conducted on data from adolescents in the Brazilian National Oral Health Survey (N = 5,445). Higher loadings were found for crowding (0.6), maxillary and mandibular irregularities (0.5), and count of communitary periodontal index (CPI) sextants with bleeding and dental calculus (0.5). The mean rates for periodontal and occlusal disorders were at least two times higher in adolescents from lower income families and those reporting the need for dental prostheses, as well as those dissatisfied with their dental and overall oral health. Increased mean rates of occlusal disorders were associated with schooling delay and history of toothache in the previous six months. The mean scores suggested accumulation of at least one of the negative oral health indicators in the lower income strata, among adolescents with schooling delay, and in those reporting dental needs. The results suggest priorities for planning and monitoring as a function of oral health requirements.Daniela de Rossi Figueiredo, João Luiz Bastos, Karen Glazer Pere
Bicudo do algodoeiro: identificação, biologia, amostragem e táticas de controle.
bitstream/CNPA/18282/1/CIRTEC79.pd
Effects of stingless bee and honey bee propolis on four species of bacteria
We examined the antibacterial activities of several types of propolis, including Africanized honey bee green propolis and propolis produced by meliponini bees. The antibacterial activity of green propolis against Micrococcus luteus and Staphylococcus aureus was superior to that of Melipona quadrifasciata and Scaptotrigona sp propolis. Only two samples of propolis (green propolis and Scaptotrigona sp propolis) were efficient against Escherichia coli. Melipona quadrifasciata propolis was better than green propolis and Scaptotrigona sp propolis against Pseudomonas aeruginosa. We concluded that these resins have potential for human and veterinary medicine.Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)CNPqFAEPAFAPES
Tolerância ao déficit hídrico em populações F2 de feijão-caupi.
Water deficit affects plant development and the overcoming of its effects depends on the genotype, duration of stress, severity of damage and development stage of the plant at water stress. Cowpea is considered tolerant to water deficit, however, studies have shown that its yield can be reduced under this condition. Thus, the objective of this work was to evaluate the effect of water deficit on F2 populations of cowpea and select tolerant genotypes..
Deformation quantization of noncommutative quantum mechanics and dissipation
We review the main features of the Weyl-Wigner formulation of noncommutative
quantum mechanics. In particular, we present a -product and a Moyal
bracket suitable for this theory as well as the concept of noncommutative
Wigner function. The properties of these quasi-distributions are discussed as
well as their relation to the sets of ordinary Wigner functions and positive
Liouville probability densities. Based on these notions we propose criteria for
assessing whether a commutative regime has emerged in the realm of
noncommutative quantum mechanics. To induce this noncommutative-commutative
transition, we couple a particle to an external bath of oscillators. The master
equation for the Brownian particle is deduced.Comment: 7 pages, Latex file, Based on a talk presented by Joao Prata at
D.I.C.E. 2006, Piombino, Ital
Análise dialélica de genótipos de feijão-caupi visando seleção para tolerância à seca.
The low use of technologies by farmers and the occurrence of biotic and abiotic stresses are limiting factors for cowpea production in the Brazilian Northeast region. The tolerance of genotypes to drought is an alternative to decrease the negative effects of stresses on cowpea production. Thus, the objective of this work was to identify parents and combinations of cowpea genotypes with high probability of generating segregating populations with tolerance to drought..
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