Pheochromocytomas and paragangliomas: from DNA to the daily clinical practice

The neuroendocrine system is a diffuse system in which the nervous system and the hormones of the endocrine glands interact. The neuroendocrine organs of the sympathetic and parasympathetic autonomic nervous system are called paraganglia. These organs usually manifest as anatomically discrete bodies, which derive from the neural crest and produce catecholamines and various peptides. Various localizations of paraganglia in the human body are known, including the adrenal gland, organs of Zuckerkandl, and carotid and aortic bodies. Paraganglia are divided into two functional groups, i.e. the sympathoadrenal and the parasympathetic autonomic nervous system. Sympathetic paraganglia are predominantly located in the prevertebral and paravertebral sympathetic trunks, and along the fibers of the hypogastric plexus, innervating pelvic and retroperitoneal organs. Parasympathetic paraganglia are almost exclusively located in the region of cranial as well as thoracic branches of the of the glossopharyngeal nerves and vagal nerves. The principal glossopharyngeal paraganglia are the tympanic (located in the wall of the middle ear), and the carotid bodies (Figure 1). Neoplasms of the paraganglia are called pheochromocytomas (PCC), sympathetic and parasympathetic paragangliomas. The name PCC is derived from the Greek synonym “dark colored tumor”, because it was first described by Pick as a chromium salt-reactive tumor which lead to dark coloration. PCC are tumors which originate in the adrenal medulla. Sympathetic paragangliomas (sPGL), in the literature often described as extra-adrenal PCC, usually produce catecholamines and occur in the abdominal cavity and the aorticopulmonary bodies, but not in the adrenal medulla. Parasympathetic paragangliomas, also called head and neck paraganglioma, usually do not produce catecholamines and are situated in the wall of the middle ear, along the vagal nerve, and the carotid and jugular bodies. In the literature they are still often referred to as chemodectomas, glomus tumors, or carotid body tumors

A thermodynamical fiber bundle model for the fracture of disordered materials

We investigate a disordered version of a thermodynamic fiber bundle model proposed by Selinger, Wang, Gelbart, and Ben-Shaul a few years ago. For simple forms of disorder, the model is analytically tractable and displays some new features. At either constant stress or constant strain, there is a non monotonic increase of the fraction of broken fibers as a function of temperature. Moreover, the same values of some macroscopic quantities as stress and strain may correspond to different microscopic cofigurations, which can be essential for determining the thermal activation time of the fracture. We argue that different microscopic states may be characterized by an experimentally accessible analog of the Edwards-Anderson parameter. At zero temperature, we recover the behavior of the irreversible fiber bundle model.Comment: 18 pages, 10 figure

Directed transport and localization in phase-modulated driven lattices

We explore the dynamics of non-interacting particles loaded into a phase-modulated one-dimensional lattice formed by laterally oscillating square barriers. Tuning the parameters of the driven unit cell of the lattice selected parts of the classical phase space can be manipulated in a controllable manner. We find superdiffusion in position space for all parameters regimes. A directed current of an ensemble of particles can be created through locally breaking the spatiotemporal symmetries of the time-driven potential. Magnitude and direction of the current are tunable. Several mechanisms for transient localization and trapping of particles in different wells of the driven unit cell are presented and analyzed

Concentração e época de aplicação de AminoetoxiVinilGlicine (AVG) na maturação de macieiras 'Fuji Suprema'.

bitstream/item/45481/1/ADM11003.pd

Spin-orbit coupled Bose-Einstein condensate in a tilted optical lattice

Bloch oscillations appear for a particle in a weakly tilted periodic potential. The intrinsic spin Hall effect is an outcome of a spin-orbit coupling. We demonstrate that both these phenomena can be realized simultaneously in a gas of weakly interacting ultracold atoms exposed to a tilted optical lattice and to a set of spatially dependent light fields inducing an effective spin-orbit coupling. It is found that both the spin Hall as well as the Bloch oscillation effects may coexist, showing, however, a strong correlation between the two. These correlations are manifested as a transverse spin current oscillating in-phase with the Bloch oscillations.Comment: 12 pages, 7 figure

Quantifying and reducing cross‐contamination in single‐ and multiplex hybridization capture of ancient DNA

The use of hybridization capture has enabled a massive upscaling in sample sizes for ancient DNA studies, allowing the analysis of hundreds of skeletal remains or sediments in single studies. Nevertheless, demands in throughput continue to grow, and hybridization capture has become a limiting step in sample preparation due to the large consumption of reagents, consumables and time. Here, we explored the possibility of improving the economics of sample preparation via multiplex capture, that is, the hybridization capture of pools of double-indexed ancient DNA libraries. We demonstrate that this strategy is feasible, at least for small genomic targets such as mitochondrial DNA, if the annealing temperature is increased and PCR cycles are limited in post-capture amplification to avoid index swapping by jumping PCR, which manifests as cross-contamination in resulting sequence data. We also show that the reamplification of double-indexed libraries to PCR plateau before or after hybridization capture can sporadically lead to small, but detectable cross-contamination even if libraries are amplified in separate reactions. We provide protocols for both manual capture and automated capture in 384-well format that are compatible with single- and multiplex capture and effectively suppress cross-contamination and artefact formation. Last, we provide a simple computational method for quantifying cross-contamination due to index swapping in double-indexed libraries, which we recommend using for routine quality checks in studies that are sensitive to cross-contamination

Dormência em frutíferas de clima temperado.

bitstream/item/44317/1/documento-310.pd

Brownian forces in sheared granular matter

We present results from a series of experiments on a granular medium sheared in a Couette geometry and show that their statistical properties can be computed in a quantitative way from the assumption that the resultant from the set of forces acting in the system performs a Brownian motion. The same assumption has been utilised, with success, to describe other phenomena, such as the Barkhausen effect in ferromagnets, and so the scheme suggests itself as a more general description of a wider class of driven instabilities.Comment: 4 pages, 5 figures and 1 tabl

Cumulants of the three state Potts model and of nonequilibrium models with C3v symmetry

The critical behavior of two-dimensional stochastic lattice gas models with C3v symmetry is analyzed. We study the cumulants of the order parameter for the three state (equilibrium) Potts model and for two irreversible models whose dynamic rules are invariant under the symmetry operations of the point group C3v. By means of extensive numerical analysis of the phase transition we show that irreversibility does not affect the critical behavior of the systems. In particular we find that the Binder reduced fourth order cumulant takes a universal value U* which is the same for the three state Potts model and for the irreversible models. The same universal behavior is observed for the reduced third-order cumulant.Comment: gzipped tar file containing: 1 latex file + 6 eps figure

Time dependence of breakdown in a global fiber-bundle model with continuous damage

A time-dependent global fiber-bundle model of fracture with continuous damage is formulated in terms of a set of coupled non-linear differential equations. A first integral of this set is analytically obtained. The time evolution of the system is studied by applying a discrete probabilistic method. Several results are discussed emphasizing their differences with the standard time-dependent model. The results obtained show that with this simple model a variety of experimental observations can be qualitatively reproduced.Comment: APS style, two columns, 4 figures. To appear in Phys. Rev.