Search results for "Reto"

3D-Ultrastructure, Functions and Stress Responses of Gastropod (Biomphalaria glabrata) Rhogocytes

2014

Rhogocytes are pore cells scattered among the connective tissue of different body parts of gastropods and other molluscs, with great variation in their number, shape and size. They are enveloped by a lamina of extracellular matrix. Their most characteristic feature is the "slit apparatus", local invaginations of the plasma membrane bridged by cytoplasmic bars, forming slits of ca. 20 nm width. A slit diaphragm creates a molecular sieve with permeation holes of 20×20 nm. In blue-blooded gastropods, rhogocytes synthesize and secrete the respiratory protein hemocyanin, and it has been proposed-though not proven-that in the rare red-blooded snail species they might synthesize and secrete the he…

Ovicide-induced serosa degeneration and its impact on embryonic development in Manduca sexta (Insecta: Lepidoptera)

2003

Abstract Eggs of Manduca sexta treated with the ovicide Ov. 165049 turn orange, and the embryos later die. The orange pigmentation is at first confined to the serosa, and is accompanied by pathological changes of serosal cells. Lipid vesicles aggregate and spindle-shaped electron-lucent vesicles—normally forming a single layer below the apical cell surface—greatly accumulate. The mitochondria swell considerably, and their matrices become electron-lucent. Subsequently, the serosal cells develop additional features of necrosis. They form many autophagic vacuoles which contain mostly degradating mitochondria, but also segregated rough endoplasmic reticulum (rER) and glycogen granules. The whol…

An Empirical Investigation of Heavy Tails in Emerging Markets and Robust Estimation of the Pareto Tail Index

2021

In this work we analyze and compare the performances of VaR-based estimatorswith respect to three different classes of distributions, i.e., Gaussian, Stable and Pareto, and to different emerging markets, i.e., Egypt, Qatar and Mexico. This is motivated by the evidence that there are points of distinction between emerging and developed markets mainly relating to the speed and reliability of information available to investors.We propose a computational Threshold Accepting-VaR based algorithm (TAVaR) for optimally estimating the Pareto tail index. A Monte Carlo bias estimation analysis is also carried out by comparing our proposed methodology with the Hill estimator and a variant of it.

Retorica e disaccordo. Intervista con Emmanuelle Danblon

2012

Cholesterol binds to synaptophysin and is required for biogenesis of synaptic vesicles.

1999

Here, to study lipid-protein interactions that contribute to the biogenesis of regulated secretory vesicles, we have developed new approaches by which to label proteins in vivo, using photoactivatable cholesterol and glycerophospholipids. We identify synaptophysin as a major specifically cholesterol-binding protein in PC12 cells and brain synaptic vesicles. Limited cholesterol depletion, which has little effect on total endocytic activity, blocks the biogenesis of synaptic-like microvesicles (SLMVs) from the plasma membrane. We propose that specific interactions between cholesterol and SLMV membrane proteins, such as synaptophysin, contribute to both the segregation of SLMV membrane constit…

INTERNAL PRESSURE AND COUNTERPUNCH ACTION DESIGN IN Y-SHAPED TUBE HYDROFORMING PROCESSES: A MULTI OBJECTIVE OPTIMISATION APPROACH

2009

In sheet metal forming most of the problems are multi-objective problems, generally characterised by conflicting objectives. A classical approach to investigate such kind of problems is focused on a combination of multiple objectives into a unique objective function to be optimised. Actually, in metal forming processes optimisation two main phases have to be developed in order to reach an optimal solution: the former is the modelling phase (definition of the design variables and objective function) and the latter concerns the computational aspect (numerical simulations or experiment to be developed). In this paper, an integration between numerical simulations, response surface methodology a…

Heuristic-Based Shiftable Loads Optimal Management in Smart Micro-Grids

2015

In this paper, an optimal power dispatch problem on a 24-h basis for distribution systems with distributed energy resources (DER) also including directly controlled shiftable loads is presented. In the literature, the optimal energy management problems in smart grids (SGs) where such types of loads exist are formulated using integer or mixed integer variables. In this paper, a new formulation of shiftable loads is employed. Such formulation allows reduction in the number of optimization variables and the adoption of real valued optimization methods such as the one proposed in this paper. The method applied is a novel nature-inspired multiobjective optimization algorithm based on an original…

Spatial trade-offs between ecological and economical sustainability in the boreal production forest

2022

Economically-oriented forestry aims to sustain timber harvest revenues, while ecologically-oriented management supplies suitable habitat for species using deadwood as primary habitat. As these objectives are conflicting, planning for economic and ecological sustainability involves compromise and trade-offs. We analyze the spatial trade-offs between the economic value from timber harvesting and the volume of deadwood in the boreal forest. We assess these trade-offs from three perspectives: (1) landscape characteristics, affected by conservation strategies; (2) forest management promoting either economic or ecological values; (3) uncertainty in inventory errors undermining the estimate of the…

Gerardi Joannis Vossii Rhetorices contractae, sive partitionum oratoriarum libri quinque / Cum tabulis synopticis M. Jacobi Thomasii ... ; Praemissus…

1781

Sig. *-*****8, A-Yy8, Zz4. - Amb portadella i pag. pròpia: Appendix triplex: I. De rhetoribus antiquis cum graecis, tum latinis. II. De hispanis purioris latinitatis cultoribus. III. De iis, qui Hispane tersius et elegantius sunt loquuti Notes a peu de p. a dues col. - Reclams. - Errates en la pag. de la segona seqüència: de la p. 152 passa a la 151

A computational proposal for a robust estimation of the Pareto tail index: An application to emerging markets

2022

Abstract In this work, we backtest and compare, under the VaR risk measure, the fitting performances of three classes of density distributions (Gaussian, Stable and Pareto) with respect to three different types of emerging markets: Egypt, Qatar and Mexico. We also propose a new technique for the estimation of the Pareto tail index by means of the Threshold Accepting (TAVaR) and the Hybrid Particle Swarm Optimization algorithm (H-PSOVaR). Furthermore, we test the accuracy and robustness of our estimates demonstrating the effectiveness of the proposed approach.