Chromatography-mass spectrometry studies on the metabolism of synthetic cannabinoids JWH-018 and JWH-073, psychoactive components of smoking mixtures

The lack or low content of their native compounds in urine requires detailed identification of their metabolites, which are excreted with urine and are present in blood. Using gas and liquid chromatography-mass spectrometry, we identified a series of metabolites in urine samples from humans and ratsyesBelgorod State Universit

4-dimensional BF Gravity on the Lattice

We propose the lattice version of $BF$ gravity action whose partition function leads to the product of a particular form of 15-$j$ symbol which corresponds to a 4-simplex. The action is explicitly constructed by lattice $B$ field defined on triangles and link variables defined on dual links and is shown to be invariant under lattice local Lorentz transformation and Kalb-Ramond gauge transformation. We explicitly show that the partition function is Pachner move invariant and thus topological. The action includes the vanishing holonomy constraint which can be interpreted as a gauge fixing condition. This formulation of lattice $BF$ theory can be generalized into arbitrary dimensions.Comment: LaTeX2e, 45 pages, 55 eps figure

On moments of a polytope

We show that the multivariate generating function of appropriately normalized moments of a measure with homogeneous polynomial density supported on a compact polytope P in R^d is a rational function. Its denominator is the product of linear forms dual to the vertices of P raised to the power equal to the degree of the density function. Using this, we solve the inverse moment problem for the set of, not necessarily convex, polytopes having a given set S of vertices. Under a weak non-degeneracy assumption we also show that the uniform measure supported on any such polytope is a linear combination of uniform measures supported on simplices with vertices in S.Comment: 28 pages, 3 figure

Caracterização de estruturas de alvenaria de pedra por recurso aos métodos do georadar, resistividade eléctrica e ensaios sónicos

A crescente preocupação com o património construído sensibilizou a população e os técnicos especializados na procura de estratégias, processos e instrumentos de apoio à caracterização das estruturas existentes e na sua reabilitação. A crescente necessidade de caracterizar o estado das estruturas construídas com recurso a métodos não destrutivos é um tema atual que tem sido alvo de diversos estudos e investigações. No presente trabalho apresentam-se três metodologias não destrutivas de caracterização de alvenarias de pedra: o método da resistividade elétrica, o étodo do georadar e o método dos ensaios sónicos. Estas metodologias foram estudadas, testadas em laboratório e aplicadas in-situ no objeto de estudo, o Solar de Lamas. Relativamente aos ensaios através do método elétrico da resistividade analisou-se a influência de fatores externos e do grau de humidade na obtenção de resultados. No que diz respeito ao método do georadar adaptou-se o equipamento e a metodologia de aquisição a ensaios sobre alvenarias de pedra com a antena de 900 MHz e foi avaliada a sua operacionalidade. Relativamente aos ensaios sónicos, foi analisada a influência de diferentes fatores na nitidez do sinal e no cálculo da velocidade de propagação de ondas sónicas, como a influência da definição da primeira chegada e sinal no cálculo da velocidade. Através dos ensaios sónicos foi ainda possível estimar o módulo de elasticidade quer de um bloco de granito estudado em laboratório como de uma parede de alvenaria estudada no Solar de Lamas.The growing concern with the constructed legacy sensitized the population and experts for strategies search, processes and tools to support the characterization of existing structures and improve their rehabilitation. The increasing need for characterization of the built structures using non-destructive methods has become a current topic that has been the subject for several studies and investigations. In this dissertation are presented three non-destructive methods for characterization of the stone masonry: the electrical resistivity method, the GPR method and the sonic tests method. These methods have been studied, tested in the laboratory and applied insitu in the study object, the Solar Lamas. For tests using the resistivity electric method was tested the geophysical acquisition on masonry walls, it was also analyzed the influence of external factors and the degree of humidity in achieving results. Regarding the GPR method a few geophysical tests were developed on stone masonry with antenna 900 MHz and its operability was evaluated. For sonic testing was examined the influence of different factors on the speed and propagation of waves as well as the influence of the setting of the first signal on waves speed calculation. Through the sonic testing it was also possible to calculate the modulus of elasticity of either the granite block studied in the laboratory and the masonry wall studded in the Solar de Lamas

Stabilization Control for the Giant Swing Motion of the Horizontal Bar Gymnastic Robot Using Delayed Feedback Control

Open-loop dynamic characteristics of an underactuated system with nonholonomic constraints, such as a horizontal bar gymnastic robot, show the chaotic nature due to its nonlinearity. This chapter deals with the stabilization problems of periodic motions for the giant swing motion of gymnastic robot using chaos control methods. In order to make an extension of the chaos control method and apply it to a new practical use, some stabilization control strategies were proposed, which were, based on the idea of delayed feedback control (DFC), devised to stabilize the periodic motions embedded in the movements of the gymnastic robot. Moreover, its validity has been investigated by numerical simulations. First, a method named as prediction-based DFC was proposed for a two-link gymnastic robot using a Poincar section. Meanwhile, a way to calculate analytically the error transfer matrix and the input matrix that are necessary for discretization was investigated. Second, an improved DFC method, multiprediction delayed feedback control, using a periodic gain, was extended to a four-link gymnastic robot. A set of plural Poincare maps were defined with regard to the original continuous-time system as a T-periodic discrete-time system. Finally, some simulation results showed the effectiveness of the proposed methods