48 research outputs found
Relaxable Damage in Hot-Carrier Stressing of n
A method for device characterization is experimented to qualify the relaxable damage in
hot-carrier stressing of n-MOS transistors. The degradation of physical parameters of
the body-drain junction of power HEXFETs is presented for applied stress condition
Vg= Vd/2. Large decrease of the resistance series, of the ideality factor, and of the reverse
recombination current are shown to be related to relaxation time, and are significant
at Vg=–Vd. These effects are discussed and explained by the evolution of the
interface states
Utilization of the Thermoelectric Sensor to Realize a New Fluid Level Detector
This paper describes a prototype thermoelectric sensor system which makes use of the
thermoelectrical effects. The sensor includes two printed circuits, the first is
constituted of a resistive constantan track, the second is a planar thermoelectric
circuit constituted of many plated differential thermocouples. The first circuit is placed
at the top of the second circuit so that the resistive tack is placed on the top of the
even thermocouple junctions. The measuring method consists to passing an electrical
current through the constantan track in order to generate temperature gradients
between the junction points of the second circuit. Then the resulting temperature
differences between the junction points is directly converted into a proportional
Seebeck voltage. As an application, the sensor is placed into a reservoir and adapted
in order to realize a fluid level detector
Design and Realization a New Thermoelectric Sensor, Application
The present paper deals with design and realization of a New thermoelectric sensor
adapted to conceive a circuit breaker, using the thermoelectric effects (Joule, Peltier and
Seebeck). The sensor includes two printed circuits. The first is constituted of two resistive
tracks of constantan, it is the transmitting circuit. The second, a planar thermoelectric
circuit acting as a receiver, is constituted of many plated differential thermocouples. The
transmitting circuit is placed on the top surface of the receiver circuit so that the resistive
tracks are placed on the levels of thermoelectric junctions. The measuring method
consists to passing electrical currents through the resistive tracks in order to generate
temperature gradients between junction points of the bimetallic circuit. Then the resulting
temperature differences between junction points is directly converted into a proportional
Seebeck voltage. As an application, the sensor is adapted to realize a differential
circuit-breaker with a low difference current
Characterization of CrN/CrAlN/Cr2O3 Multilayers Coatings Synthesized by DC Reactive Magnetron Sputtering
The CrN/CrAlN/Cr2O3 multilayer coatings were deposited by reactive magnetron sputtering DC on 90CrMoV8 stainless steel under various oxygen flow rates. The structure and crystalline phases are characterized by the x-ray diffractometer. Through SEM, a dense and coherent is revealed in CrN/CrAlN/Cr2O3 multilayer coatings. The friction and wear behaviors obtained with the ball-on-disc test show that all multilayer films exhibit a good wear resistance, especially the one with an oxygen flow rate of 10 sccm. Nevertheless, in sea water the film without a top layer of Cr2O3 have the lowest coefficient of friction. This behavior is attributed to the interfacial strengthening and the existence of the upper passivation layer Cr2O3. Adding to that, the film obtained under an oxygen flow rate of 10 sccm show the lowest grain size and the maximum hardness and elastic modulus could Respectively, 45 and 417 GPa.RĂ©gion Bourgogn
Cellular dissection of psoriasis for transcriptome analyses and the post-GWAS era
Abstract
Background
Genome-scale studies of psoriasis have been used to identify genes of potential relevance to disease mechanisms. For many identified genes, however, the cell type mediating disease activity is uncertain, which has limited our ability to design gene functional studies based on genomic findings.
Methods
We identified differentially expressed genes (DEGs) with altered expression in psoriasis lesions (n = 216 patients), as well as candidate genes near susceptibility loci from psoriasis GWAS studies. These gene sets were characterized based upon their expression across 10 cell types present in psoriasis lesions. Susceptibility-associated variation at intergenic (non-coding) loci was evaluated to identify sites of allele-specific transcription factor binding.
Results
Half of DEGs showed highest expression in skin cells, although the dominant cell type differed between psoriasis-increased DEGs (keratinocytes, 35%) and psoriasis-decreased DEGs (fibroblasts, 33%). In contrast, psoriasis GWAS candidates tended to have highest expression in immune cells (71%), with a significant fraction showing maximal expression in neutrophils (24%, P < 0.001). By identifying candidate cell types for genes near susceptibility loci, we could identify and prioritize SNPs at which susceptibility variants are predicted to influence transcription factor binding. This led to the identification of potentially causal (non-coding) SNPs for which susceptibility variants influence binding of AP-1, NF-κB, IRF1, STAT3 and STAT4.
Conclusions
These findings underscore the role of innate immunity in psoriasis and highlight neutrophils as a cell type linked with pathogenetic mechanisms. Assignment of candidate cell types to genes emerging from GWAS studies provides a first step towards functional analysis, and we have proposed an approach for generating hypotheses to explain GWAS hits at intergenic loci.http://deepblue.lib.umich.edu/bitstream/2027.42/109537/1/12920_2013_Article_485.pd
Twelve-month observational study of children with cancer in 41 countries during the COVID-19 pandemic
Introduction Childhood cancer is a leading cause of death. It is unclear whether the COVID-19 pandemic has impacted childhood cancer mortality. In this study, we aimed to establish all-cause mortality rates for childhood cancers during the COVID-19 pandemic and determine the factors associated with mortality. Methods Prospective cohort study in 109 institutions in 41 countries. Inclusion criteria: children <18 years who were newly diagnosed with or undergoing active treatment for acute lymphoblastic leukaemia, non-Hodgkin's lymphoma, Hodgkin lymphoma, retinoblastoma, Wilms tumour, glioma, osteosarcoma, Ewing sarcoma, rhabdomyosarcoma, medulloblastoma and neuroblastoma. Of 2327 cases, 2118 patients were included in the study. The primary outcome measure was all-cause mortality at 30 days, 90 days and 12 months. Results All-cause mortality was 3.4% (n=71/2084) at 30-day follow-up, 5.7% (n=113/1969) at 90-day follow-up and 13.0% (n=206/1581) at 12-month follow-up. The median time from diagnosis to multidisciplinary team (MDT) plan was longest in low-income countries (7 days, IQR 3-11). Multivariable analysis revealed several factors associated with 12-month mortality, including low-income (OR 6.99 (95% CI 2.49 to 19.68); p<0.001), lower middle income (OR 3.32 (95% CI 1.96 to 5.61); p<0.001) and upper middle income (OR 3.49 (95% CI 2.02 to 6.03); p<0.001) country status and chemotherapy (OR 0.55 (95% CI 0.36 to 0.86); p=0.008) and immunotherapy (OR 0.27 (95% CI 0.08 to 0.91); p=0.035) within 30 days from MDT plan. Multivariable analysis revealed laboratory-confirmed SARS-CoV-2 infection (OR 5.33 (95% CI 1.19 to 23.84); p=0.029) was associated with 30-day mortality. Conclusions Children with cancer are more likely to die within 30 days if infected with SARS-CoV-2. However, timely treatment reduced odds of death. This report provides crucial information to balance the benefits of providing anticancer therapy against the risks of SARS-CoV-2 infection in children with cancer
NUMERICAL SIMULATION AND OPTIMIZATION OF PERFORMANCES OF A SOLAR CELL BASED ON CdTe
<p>This article has as an aim the study and the simulation of the photovoltaic cells containing CdTe materials, contributing to the development of renewable energies, and able to feed from the houses, the shelters as well as photovoltaic stations… etc. CdTe is a semiconductor having a structure of bands with an indirect gap of a value of 1,5 eV at ambient temperature what means that photon wavelength of approximately 1200 nm will be able to generate an electron-hole pair. One speaks about photogeneration. We will lay the stress, initially, on the essential design features of a photovoltaic module (the open-circuit tension, the short-circuit current, the fill factor, and the output of the cell)<strong>, </strong>our results was simulated with the SCAPS computer code in one dimension which uses electrical characteristics DC and AC of the thin layers heterojunctions. The results obtained after optimization are: V<sub>CO</sub> = 0.632V, Jsc = 39.1 mA/cm2, FF=82.98 % and the output energy of conversion is 18.26%.Optimization is made according to the temperature and the wavelength.</p
A multilayer model for describing hardness variations of aged porous silicon low-dielectric-constant thin films
International audienceThis paper reports on the micro-instrumented indentation of a porous silicon structure obtained by anodization of a highly p(+)-doped (100) silicon substrate aged over 1 week. The three-layer structure obtained consists of oxidized porous silicon (cap-layer), porous silicon (inner-layer) and silicon substrate. The hardness curve has the typical "U shape" of low-dielectric-constant films when the indentation depth rises: the early decrease in hardness, due to the soft inner layer, is followed by an increase, due to the hard substrate. A multilayer model is developed to account for hardness variation with respect to the applied load. This model considers the crumbling of the cap-layer and of the inner porous structure. As a result, it is shown that considering the minima in the U shape gives an over-estimated value when it comes to assessing the coating hardness. in our experiment, this minimum depends on both the hardness and the thickness of the but not on the mechanical properties of the substrate, even for indentation depths slightly oxidized cap layer, lower than the film's thickness. (C) 2009 Elsevier B.V. All rights reserved
Influence of the Laser on the Mechanical Properties of GeSe9 Chalcogenide Glasses
International audiencePhotoinduced changes in the mechanical properties of Ge-Se chalcogenide glasses produced by sub-band gap energy are studied by microindentation. The results show that the irradiation leads to an increase of the mechanical properties exactly module of Young and the hardness with a decrease of the viscosity in the case of the low intensities laser and a decrease of the mechanical properties with an increase of the viscosity in the case of the high intensities of irradiation