Search results for "SIP"

Structures optiques dissipatives en cavité laser à fibre

2011

This thesis presents a study of the nonlinear dissipative dynamics of localized of self organized structures in passively mode-locked fiber laser through nonlinear polarization evolution. We reveal the existence of a gradual transition from the quasi-cw to mode locked dynamics in the multi-pulsing regime. We emphasize on the intermediate state, where various new dynamics are observed. We study collective behaviors of dissipative solitons in the presence of a continuous background. One of the complex and attractive dynamics presented is the "soliton rain", which composed of three field components : continuous modes of background, drifting of solitons and condensed phase solitons. This dynami…

Analysis of the multipactor effect by means of the 3D BI-RME method

2017

Multipactor effect is a well-known phenomenon of RF breakdown in satellite pay-loads which degrades components, generates undesirable harmonics, contributes to power dissipation and increases noise in communications. Traditionally, multipactor has been investigated with the aim of obtaining the so-called multipactor threshold voltage, or to present different multipaction detection methods. Little effort has been devoted, in contrast, to study the problem from a full-wave point of view, thus allowing for the analysis of more complex structures. The main goal of this work is to analyze the interaction between a multipactor current and a realistic microwave cavity by means of a rigorous and ac…

Geographic variation of the Greater white-toothed shrew (Crocidura russula Hermann, 1780 Mammalia, Soricidae)

1996

A multivariate morphometric study of the Greater white-toothed shrew (C. russula) throughout its Palearctic range was carried out to search for patterns of geographic variation within the species boundary. Burnaby's and multiple group principal component analysis allowed the adjustment of raw data with respect to within-sample allometric variation. Multivariate 'size-free' results show a stepped cline with the phenotypical trait reduction and shape change from the eastern to the western Maghreb. Pleistocene fossil mandibles proved to have low phenetic distances with eastern populations (Tunisia, east Algeria) and it is argued that their character set is the primitive condition. The ancestra…

Marxist Influences in Psychology

2020

Marxist ideas influenced and inspired psychological thinking and practice in the 20th century in a range of ways. In different parts of the world, unique versions of Marxist psychology emerged as answers to questions and problems raised by specific historical contexts. As shown in the early 21st century scholarly interventions in Lev Vygotsky studies, the Soviet psychologist’s work was deeply embedded in the sociopolitical, cultural, and ideological context of early Soviet Russia. In countries such as Brazil and Italy, Marxism had a more indirect influence as an emancipatory discourse. In the wider framework of Latin American liberatory ideas and struggles, the educational philosopher Paulo…

Probing Surface Quantum Flows in Deformed Pygmy Dipole Modes

2017

In order to explore the nature of collective modes in weakly bound nuclei, we have investigated deformation effects and surface flow patterns of isovector dipole modes in a shape-coexisting nucleus $^{40}$Mg. The calculations were done in a fully self-consistent continuum finite-amplitude Quasiparticle Random Phase Approximation (QRPA) in a large deformed spatial mesh. An unexpected result of pygmy and giant dipole modes having disproportionate deformation splittings in strength functions was obtained. Furthermore, the transition current densities demonstrate that the long-sought core-halo oscillation in pygmy resonances is collective and compressional, corresponding to the lowest excitatio…

Alternating-Current Properties of Elastomer-Carbon Nanocomposites

2004

Respiratory proteins in Sipunculus nudus--implications for phylogeny and evolution of the hemerythrin family.

2009

Three major classes of respiratory proteins are known, hemoglobin, molluscan and arthropod hemocyanin, and hemerythrin (Hr). Similar to hemoglobin, respiratory Hr is packed into erythrocytes floating in the coelomic fluid and is only known from sipunculids, brachiopods, and priapulids. Owing to this scattered distribution, the presence of Hr is generally assumed to be the plesiomorphic condition without phylogenetic importance. By sequencing 2000 Expressed Sequence Tags (ESTs) from Sipunculus nudus, we found 75 Hr-coding ESTs assembled to 20 cDNA contigs classified as four distinct Hr isoforms: three polymeric Hrs (subunit A, A', and B) and the monomeric myo-hemerythrin (myoHr). Phylogeneti…

Reactive oxygen species induced by beauvericin, patulin and zearalenone in CHO-K1 cells

2008

The cytotoxic effects of mycotoxins, induction of reactive oxygen species (ROS) and generation of lipid peroxidation products in CHO-K1 cells were determined as function of increasing time of exposure and concentrations of beauvericin (BEA), patulin (PAT) and zearalenone (ZEA). The end points were evaluated after 24h of exposure, by the tetrazolium salt (MTT) and neutral red (NR) assays. The IC(50) values obtained on the MTT and NR assays ranged from 0.69 to 79.40 microM and 4.40 to 108.76 microM, respectively. To determine the intracellular production of ROS, the intensity of fluorescence emitted from the probe H(2)-DCFDA was measured. The relative intensity of fluorescence from cells incu…

Toxicological interactions between the mycotoxins beauvericin, deoxynivalenol and T-2 toxin in CHO-K1 cells in vitro.

2011

Abstract Beauvericin (BEA), deoxynivalenol (DON) and T-2 toxin (T-2) are important food-borne mycotoxins that have been implicated in human health. In this study, the acute toxicity of individual and combined mycotoxins (BEA, DON and T-2) were tested in immortalized hamster ovarian cells (CHO-K1) at 24, 48 and 72 h of exposure, by the tetrazolium salt (MTT) and neutral red (NR) assays. The IC50 values obtained for all mycotoxins by the MTT and NR assays ranged from 0.017 to 12.08 μM and from 0.042 to 17.22 μM, respectively. Both, individual and combined mycotoxins demonstrated a significant cytotoxic effect in CHO-K1 cells in a dose-dependent manner. When mycotoxins were assayed individuall…

Disentangling decaying isomers and searching for signatures of collective excitations in β decay

2019

6 pags., 3 figs., 1 tab. -- 27th International Nuclear Physics Conference (INPC2019) 29 July - 2 August 2019, Glasgow, UK