24 research outputs found
Status of Uncooled Infrared Detector Technology at ULIS, France
The high level of accumulated expertise by ULIS and CEA/LETI on uncooled microbolometers made from amorphous silicon enables ULIS to develop uncooled IRFPA with 17 µm pixel-pitch to enable the development of small power, small weight and power (SWaP) and high performance IR systems. Key characteristics of amorphous silicon based uncooled IR detector is described to highlight the advantage of this technology for system operation. A full range of products from 160 x 120 to 1024 x 768 has been developed and we will focus the paper on the ¼ VGA with 17 µm pixel pitch. Readout integrated circuit (ROIC) architecture is described highlighting innovations that are widely on-chip implemented to enable an easier operation by the user. The detector configuration (integration time, windowing, gain, scanning direction), is driven by a standard I²C link. Like most of the visible arrays, the detector adopts the HSYNC/VSYNC free-run mode of operation driven with only one master clock (MC) supplied to the ROIC which feeds back pixel, line and frame synchronisation. On-chip PROM memory for customer operational condition storage is available for detector characteristics. Low power consumption has been taken into account and less than 60 mW is possible in analogue mode at 60 Hz. A wide electrical dynamic range (2.4V) is maintained despite the use of advanced CMOS node. The specific appeal of this unit lies in the high uniformity and easy operation it provides. The reduction of the pixel-pitch turns this TEC-less ¼ VGA array into a product well adapted for high resolution and compact systems. Noise equivalent temperature difference (NETD) of 35 mK and thermal time constant of 10 ms have been measured leading to 350 mK.ms figure of merit. We insist on NETD trade-off with wide thermal dynamic range, as well as the high characteristics uniformity and pixel operability, achieved thanks to the mastering of the amorphous silicon technology coupled with the ROIC design. This technology node associated with advanced packaging technique, paves the way to compact low power system.Defence Science Journal, 2013, 63(6), pp.545-549, DOI:http://dx.doi.org/10.14429/dsj.63.5753
FUS and TARDBP but Not SOD1 Interact in Genetic Models of Amyotrophic Lateral Sclerosis
Mutations in the SOD1 and TARDBP genes have been commonly identified in Amyotrophic Lateral Sclerosis (ALS). Recently, mutations in the Fused in sarcoma gene (FUS) were identified in familial (FALS) ALS cases and sporadic (SALS) patients. Similarly to TDP-43 (coded by TARDBP gene), FUS is an RNA binding protein. Using the zebrafish (Danio rerio), we examined the consequences of expressing human wild-type (WT) FUS and three ALS–related mutations, as well as their interactions with TARDBP and SOD1. Knockdown of zebrafish Fus yielded a motor phenotype that could be rescued upon co-expression of wild-type human FUS. In contrast, the two most frequent ALS–related FUS mutations, R521H and R521C, unlike S57Δ, failed to rescue the knockdown phenotype, indicating loss of function. The R521H mutation caused a toxic gain of function when expressed alone, similar to the phenotype observed upon knockdown of zebrafish Fus. This phenotype was not aggravated by co-expression of both mutant human TARDBP (G348C) and FUS (R521H) or by knockdown of both zebrafish Tardbp and Fus, consistent with a common pathogenic mechanism. We also observed that WT FUS rescued the Tardbp knockdown phenotype, but not vice versa, suggesting that TARDBP acts upstream of FUS in this pathway. In addition we observed that WT SOD1 failed to rescue the phenotype observed upon overexpression of mutant TARDBP or FUS or upon knockdown of Tardbp or Fus; similarly, WT TARDBP or FUS also failed to rescue the phenotype induced by mutant SOD1 (G93A). Finally, overexpression of mutant SOD1 exacerbated the motor phenotype caused by overexpression of mutant FUS. Together our results indicate that TARDBP and FUS act in a pathogenic pathway that is independent of SOD1
Status of Uncooled Infrared Detector Technology at ULIS, France
The high level of accumulated expertise by ULIS and CEA/LETI on uncooled microbolometers made from amorphous silicon enables ULIS to develop uncooled IRFPA with 17 µm pixel-pitch to enable the development of small power, small weight and power (SWaP) and high performance IR systems. Key characteristics of amorphous silicon based uncooled IR detector is described to highlight the advantage of this technology for system operation. A full range of products from 160 x 120 to 1024 x 768 has been developed and we will focus the paper on the ¼ VGA with 17 µm pixel pitch. Readout integrated circuit (ROIC) architecture is described highlighting innovations that are widely on-chip implemented to enable an easier operation by the user. The detector configuration (integration time, windowing, gain, scanning direction), is driven by a standard I²C link. Like most of the visible arrays, the detector adopts the HSYNC/VSYNC free-run mode of operation driven with only one master clock (MC) supplied to the ROIC which feeds back pixel, line and frame synchronisation. On-chip PROM memory for customer operational condition storage is available for detector characteristics. Low power consumption has been taken into account and less than 60 mW is possible in analogue mode at 60 Hz. A wide electrical dynamic range (2.4V) is maintained despite the use of advanced CMOS node. The specific appeal of this unit lies in the high uniformity and easy operation it provides. The reduction of the pixel-pitch turns this TEC-less ¼ VGA array into a product well adapted for high resolution and compact systems. Noise equivalent temperature difference (NETD) of 35 mK and thermal time constant of 10 ms have been measured leading to 350 mK.ms figure of merit. We insist on NETD trade-off with wide thermal dynamic range, as well as the high characteristics uniformity and pixel operability, achieved thanks to the mastering of the amorphous silicon technology coupled with the ROIC design. This technology node associated with advanced packaging technique, paves the way to compact low power system.Defence Science Journal, 2013, 63(6), pp.545-549, DOI:http://dx.doi.org/10.14429/dsj.63.5753
Effect of boron on the structural and electrochemical properties of nanocrystalline Ti\u2082RuFeB\u2093 electrodes
The effect of the boron content on the structural and electrochemical properties of nanocrystalline Ti\u2082RuFeB\u2093 (with x varying from 0 to 12) was studied. The nanocrystalline materials were prepared by high energy ball milling and their structural evolution was analyzed by X-ray and neutron diffraction. Through a detailed Rietveld refinement analysis of the structural data, it is shown that the nanocrystalline materials are mainly composed of a B2 structure at low boron content (0 < x < 2). At higher boron content, TiB\u2082 is mainly formed and the B2 structure disappears with the concurrent formation of a highly disordered Ru-rich phase. These electrodes were tested for the hydrogen evolution reaction in both NaOH and chlorate solutions. The best results are obtained for 4 64 x 64 6, with a cathodic overpotential at 12250 mA/cm\ub2, \u3b7\u2082\u2085\u2080, of 3c 12575 mV. Accelerated aging tests and continuous electrolysis tests show that \u3b7\u2082\u2085\u2080 does not vary with time, contrary to the case of Ti\u2082RuFe, which shows a rapid deterioration of the cathodic overpotential after a few hours of continuous electrolysis. This is explained by the lower solubility of hydrogen in Ti\u2082RuFeB\u2084 as opposed to Ti\u2082RuFe.NRC publication: Ye
Exploration of nuclear body-enhanced sumoylation reveals that PML represses 2-cell features of embryonic stem cells
International audienceMembrane-less organelles are condensates formed by phase separation whose functions often remain enigmatic. Upon oxidative stress, PML scaffolds Nuclear Bodies (NBs) to regulate senescence or metabolic adaptation. PML NBs recruit many partner proteins, but the actual biochemical mechanism underlying their pleiotropic functions remains elusive. Similarly, PML role in embryonic stem cell (ESC) and retro-element biology is unsettled. Here we demonstrate that PML is essential for oxidative stress-driven partner SUMO2/3 conjugation in mouse ESCs (mESCs) or leukemia, a process often followed by their poly-ubiquitination and degradation. Functionally, PML is required for stress responses in mESCs. Differential proteomics unravel the KAP1 complex as a PML NB-dependent SUMO2-target in arsenic-treated APL mice or mESCs. PML-driven KAP1 sumoylation enables activation of this key epigenetic repressor implicated in retro-element silencing. Accordingly, Pml −/− mESCs re-express transposable elements and display 2-Cell-Like features, the latter enforced by PML-controlled SUMO2-conjugation of DPPA2. Thus, PML orchestrates mESC state by coordinating SUMO2-conjugation of different transcriptional regulators, raising new hypotheses about PML roles in cancer