682 research outputs found
Variational Displacement Method for Geosynthetically Reinforced Slope Stability Analysis:II. Global Stability
International audienceThis paper presents the global stability analysis of geosynthetically reinforced slopes. It is a development of the French “displacement method” for geosynthetically reinforced slope stability analysis. The global stability analysis requires the determination of the reinforcement tensions, which is presented in a companion paper. In this paper, the variational limit equilibrium method, formulated by Baker and Garber in the case of unreinforced slopes, is applied to the case of reinforced slopes. This variational analysis has shown that the results obtained by Baker and Garber are still valid in the present case. A parametric study showing the influence of different geometrical parameters on the design is presented and discussed. These results are compared with those of the original “displacement method”, in order to show the improvement of the method
Monte Carlo transient phonons transport in silicon and germanium at nanoscales
Heat transport at nanoscales in semiconductors is investigated with a
statistical method. The Boltzmann Transport Equation (BTE) which characterize
phonons motion and interaction within the crystal lattice has been simulated
with a Monte Carlo technique. Our model takes into account media frequency
properties through the dispersion curves for longitudinal and transverse
acoustic branches. The BTE collisional term involving phonons scattering
processes is simulated with the Relaxation Times Approximation theory. A new
distribution function accounting for the collisional processes has been
developed in order to respect energy conservation during phonons scattering
events. This non deterministic approach provides satisfactory results in what
concerns phonons transport in both ballistic and diffusion regimes. The
simulation code has been tested with silicon and germanium thin films;
temperature propagation within samples is presented and compared to analytical
solutions (in the diffusion regime). The two materials bulk thermal
conductivity is retrieved for temperature ranging between 100 K and 500 K. Heat
transfer within a plane wall with a large thermal gradient (250 K-500 K) is
proposed in order to expose the model ability to simulate conductivity thermal
dependence on heat exchange at nanoscales. Finally, size effects and validity
of heat conduction law are investigated for several slab thicknesses
New insights in the pathogenesis of T-cell lymphomas.
Peripheral T-cell lymphomas (PTCLs) represent diverse and aggressive malignancies, with few recent therapeutic improvements. Recent high-throughput genomic studies have revealed the complex mutational landscape of these rare diseases. These novel findings provide the grounds to a more comprehensive classification of these diseases, reflected in the 2017 WHO classification.
Our review is focused on selected PTCL entities. Angioimmunoblastic T-cell lymphoma and other lymphomas derived from T follicular helper cells feature a rather homogeneous mutational landscape. These neoplasms recapitulate a multistep oncogenic process associating epigenetic deregulation, and second hit mutations affecting the T-cell receptor signaling pathway. This model inferred from comprehensive analyses of patients samples, was confirmed in mouse models. Among ALK-negative anaplastic large-cell lymphomas, translocation-associated subsets are found in both systemic and cutaneous types, and the newly described breast implant-associated type is usually indolent. Extranodal lymphomas of the innate immune system also harbor a combination of mutations affecting different classes of epigenetic modifiers, and mutation-induced activation of the Janus Kinase/signal transduction and activator of transcription pathway.
Understanding of PTCL pathogenesis has substantially improved, and oncogenic events have been identified. The current challenge is to mount efficient therapeutic strategies targeting these aberrations to improve patients' outcome
Modeling semi-conductor thermal properties. The dispersion role
We study heat transport in semiconductor nanostructures by solving the
Boltzmann Transport Equation (BTE) by means of the Discrete Ordinate Method
(DOM). Relaxation time and phase and group velocitiy spectral dependencies are
taken into account. The Holland model of phonon relaxation time is revisited
and recalculated from dispersion relations (taken in litterature) in order to
match bulk silicon and germanium values. This improved model is then used to
predict silicon nanowire and nanofilm thermal properties in both ballistic and
mesoscopic regimes
The Nearby Supernova Factory
The Nearby Supernova Factory (SNfactory) is an ambitious project to find and
study in detail approximately 300 nearby Type Ia supernovae (SNe~Ia) at
redshifts 0.03<z<0.08. This program will provide an exceptional data set of
well-studied SNe in the nearby smooth Hubble flow that can be used as
calibration for the current and future programs designed to use SNe to measure
the cosmological parameters. The first key ingredient for this program is a
reliable supply of Hubble-flow SNe systematically discovered in unprecedented
numbers using the same techniques as those used in distant SNe searches. In
2002, 35 SNe were found using our test-bed pipeline for automated SN search and
discovery. The pipeline uses images from the asteroid search conducted by the
Near Earth Asteroid Tracking group at JPL. Improvements in our subtraction
techniques and analysis have allowed us to increase our effective SN discovery
rate to ~12 SNe/month in 2003.Comment: 7 pages, 3 figures to be published in New Astronomy Review
In vivo study of the GC90/IRIV vaccine for immune response and autoimmunity into a novel humanised transgenic mouse
Parathyroid hormone-related protein (PTH-rP), a secreted protein produced by prostate carcinoma and other epithelial cancers, is considered a key agent for the development of bone metastases. We investigated the construct GC90/IRIV, composed of immunopotentiating reconstituted influenza virosomes (IRIV) containing PTH-rP gene plasmids (GC90), as a potential tool for human anticancer immunotherapy into humanised mice transgenic for HLA-A(*)02.01, the human-β2 microglobulin, and the human CD8α molecule. Intranasal administration of GC90/IRIV resulted in the induction of a PTH-rP-specific multiepitope cytotoxic T-cell (CTL) response. Cytotoxic T cells derived from vaccinated mice were capable of lysing in vitro syngenic murine PTH-rP transfectants and human HLA-A(*)02.01+/PTH-rP+ prostate carcinoma LNCaP cells as well. The immune response capacity and the absence of any sign of toxicity and/or autoimmunity in vivo suggest the GC90/IRIV vaccine as a valid tool for active specific immunotherapy of human cancers and metastases overexpressing PTH-rP
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