Displacement Damage Effects in Pinned Photodiode CMOS Image Sensors

This paper investigates the effects of displacement damage in Pinned Photodiode (PPD) CMOS Image Sensors (CIS) using proton and neutron irradiations. The DDD ranges from 12 TeV/g to ${1.2 times 10^{6}}$ TeV/g. Particle fluence up to $5 times 10^{14}$ n.cm $^{-2}$ is investigated to observe electro-optic degradation in harsh environments. The dark current is also investigated and it would appear that it is possible to use the dark current spectroscopy in PPD CIS. The dark current random telegraph signal is also observed and characterized using the maximum transition amplitude

Assessment of Ge-doped optical fibres as a TSL-mode detector

International audienceThis study analyses the thermally stimulated luminescence or thermoluminescence (TL) glow curve between 300 and 773 K of germanium-doped silica optical fibre. A main glow peak at 530 K with a characteristic spectral emission centred at 400 nm is found. Both features are particularly suitable for dosimetry. Thus, an investigation by the TL technique of some first clinically relevant features of a TL sensor like the dose- and dose rate-responses is examined. The presented studies show that germanium doped silica fibres have potential dosimetric properties and should be excellent TL-mode detectors in instances of radiotherapy (clinical dosimetry) and in-vivo radiation dosimetry as well in the field of nuclear facilities

ALTITUDE AND FOOTBALL: WHAT ARE NEW METHODS AND OPPORTUNITIES TO MAXIMIZE PLAYERS' FITNESS?

International audiencePlaying football competition at terrestrial altitude is not an isolated phenomenon. For instance, eight of the last 19 football FIFA World Cup tournaments were hosted by countries located at low-to-moderate altitude. While football-required fitness and technical qualities are affected by the development of neuromuscular fatigue at sea level, hypoxia-induced decrease in convective oxygen transport further hinders the aerobic capacity but also the ability to perform consecutive sprints, eventually impacting the outcome of a game. This results from the decrease in partial pressure of oxygen which reduces maximal aerobic power. The later, in turn, increases the relative intensity of any given absolute level of work, potentially delaying recovery of high-energy phosphates between high-intensity intermittent efforts. Despite reduction in air resistance (caused by the decrease in air density) could facilitate high-velocity running, it can also alter drag and lift, thereby impairing sensorimotor skills. Conversely, altitude/hypoxic training could help footballers preparing for competition at altitude, but also at sea level. Traditional altitude training camps involve chronic exposure to low-to-moderate terrestrial or simulated altitudes (14%) for improving oxygen-carrying capacity. While "live high-train high" or "live high-train low" paradigms are actually implemented by many elite club or national team football squads, the benefits they may have on (repeated-) sprint performance are still debated. The development of hypoxic technologies has led to the emergence of "live low-train high" methods, in isolation (i.e., the "repeated-sprint training in hypoxia" and "resistance training in hypoxia") or in combination with hypoxic/altitude residence (i.e., "live high-train low and high"). Today, the panorama of altitude/hypoxic training methods is wider than ever and includes also practices such as "blood flow restriction" or "ischemic preconditioning", which demonstrate encouraging preliminary results. The aims of this chapter are twofold: First, to summarize the effects of acute altitude/hypoxia exposure on football-specific qualities measured in the laboratory and/or during games at terrestrial altitude. Second, to discuss the potential benefits of each altitude/hypoxic training method in respect to sport-specific physiological and fitness development and/or in-game performance

Caractérisation structurale et fonctionnelle d'une lectine de type-C des cellules de Langerhans (La Langérine)

Les cellules dendritiques jouent un rôle primordial dans le système immunitaire. En effet, ces cellules sont à l'interface entre l'immunité innée et adaptative par leur capacité de reconnaissance, d'internalisation et de dégradation de pathogènes afin de présenter des antigènes aux lymphocytes. La capacité de reconnaissance est engendrée par l'expression de différents récepteurs à la surface de ces cellules. Parmi ces récepteurs, deux grandes familles permettent la reconnaissance d'un large panel de différents pathogènes, comme les TLRs ( Toll-Like Receptors) et les lectines de type-C. Ces récepteurs sont utilisés comme marqueurs des différents sous-types de cellules dendritiques. Par exemple, parmi les lectines de type-C, DC-SIGN est majoritairement exprimée dans les cellules dendritiques dermiques alors que la Langérine est, quand à elle, fortement exprimée par les cellules dendritiques épidermiques, les cellules de Langerhans. Ces deux sous-types de cellules dendritiques divergent par leur réponse à l'infection par le VIH ( virus d'immunodéficience humain ). En effet, le virus utilise DC-SIGN pour détourner le rôle de ces cellules afin d'infecter les lymphocytes T alors que la reconnaissance du VIH par la Langérine, dans les cellules de Langerhans, conduit à la clairance de virus par son internalisation dans le granule de Birbeck. Cet organite est spécifique des cellules de Langerhans et nécessite l'expression de la Langérine. Ce travail de thèse s'est donc focalisé sur la caractérisation structurale et fonctionnelle de la Langérine. Il a permis de mettre en évidence l'importance de la structure tertiaire du domaine CRD et de la structure quaternaire de la protéine pour la formation et la bonne structuration du granule de Birbeck. Ensuite, l'étude fonctionnelle de cette lectine, notamment par résonance plasmonique de surface, nous a conduit à identifier une nouvelle spécificité de reconnaissance de la Langérine pour les glycosaminoglycanes dans un site d'interaction différent du site canonique. Enfin, nous avons caractérisé une spécificité de reconnaissance du site canonique pour les monosaccharides sulfatés de type glucosamine en utilisant la résonance plasmonique de surface et la cristallographie.Dendritic cells play a crucial role in the immune system. Indeed, these cells are at the interface between innate and acquired immunity by their capacities of recognition, internalisation and pathogen degradation to present antigens to T lymphocytes. The recognition capacity is generated by the expression of diverse receptors onto the cell surface. Among these receptors, two large families allow the recognition of a large panel of different pathogens, as TLRs ( Toll-Like Receptor) and C-type lectins. These receptors are used as markers of different dendritic cells subtypes. For example, and among the C-type lectins, DC-SIGN is mainly expressed onto dermic dendritic cells contrary to langerin, which is highly expressed onto epidermic dendritic cells, called Langerhans cells. These two subtypes of dendritic cells differ in their response of HIV infection. Indeed, the virus recognition by DC-SIGN enables hijacking the dendritic cell to infect T lymphocyte contrary to langerin recognition, in Langerhans cells, which allows the clearance of the virus by its internalisation into Birbeck granules. This organite is specific of Langerhans cells and requires langerin expression. This work is focused on structural and functional characterisation of langerin. It highlights the importance of the CRD tertiary structure and the quaternary structure of the protein for the formation and the structure of Birbeck granules. Then, functional study by surface plasmon resonance enabled us to identify a new binding site of langerin for glycosaminoglycans. Finally, we have characterised a recognition specificity of langerin for sulphated monosaccharide of glucosamine type using surface plasmon resonance and crystallography.SAVOIE-SCD - Bib.électronique (730659901) / SudocGRENOBLE1/INP-Bib.électronique (384210012) / SudocGRENOBLE2/3-Bib.électronique (384219901) / SudocSudocFranceF

Radiation Effects in Pinned Photodiode CMOS Image Sensors: Pixel Performance Degradation Due to Total Ionizing Dose

Several Pinned Photodiode (PPD) CMOS Image Sensors (CIS) are designed, manufactured, characterized and exposed biased to ionizing radiation up to 10 kGy(SiO2 ). In addition to the usually reported dark current increase and quantum efficiency drop at short wavelengths, several original radiation effects are shown: an increase of the pinning voltage, a decrease of the buried photodiode full well capacity, a large change in charge transfer efficiency, the creation of a large number of Total Ionizing Dose (TID) induced Dark Current Random Telegraph Signal (DC-RTS) centers active in the photodiode (even when the Transfer Gate (TG) is accumulated) and the complete depletion of the Pre-Metal Dielectric (PMD) interface at the highest TID leading to a large dark current and the loss of control of the TG on the dark current. The proposed mechanisms at the origin of these degradations are discussed. It is also demonstrated that biasing (i.e., operating) the PPD CIS during irradiation does not enhance the degradations compared to sensors grounded during irradiation

Activation of p34cdc2 protein kinase by microinjection of human cdc25C into mammalian cells. Requirement for prior phosphorylation of cdc25C by p34cdc2 on sites phosphorylated at mitosis.

International audienceHuman cdc25C protein, a specific tyrosine phosphatase that activates the p34cdc2 protein kinase at mitosis, is itself a phosphoprotein that shows increased phosphorylation during the G2-M transition. In vitro, cdc25C protein is substantially phosphorylated by purified p34cdc2-cyclin B protein kinase. Of seven putative phosphorylation sites for p34cdc2 protein kinase present in human cdc25C, five are phosphorylated by p34cdc2 protein kinase in vitro, as assessed by tryptic phosphopeptide mapping and peptide sequencing. These same sites are also phosphorylated in vivo during the G2-M transition in normal mammalian fibroblasts and have been precisely mapped. The cdc25C phosphorylated in vitro by p34cdc2 protein kinase exhibits a 2-3-fold higher activity than the nonphosphorylated cdc25C, as assayed by activation of inactive cdc2 prokinase. Microinjection of purified cdc25C proteins into living fibroblasts reveals that only the phosphorylated form of cdc25 is highly effective in activating G2 cells into premature prophase in a manner similar to microinjection of purified active p34cdc2 protein kinase. Together these data show that multisite phosphorylation of cdc25C by p34cdc2-cyclin B protein kinase occurs at the G2-M transition and is sufficient to induce the autoamplification of cdc2/M-phase promoting factor necessary to drive somatic mammalian cells into mitosis

Radiation Hardening of Digital Color CMOS Camera-on-a-Chip Building Blocks for Multi-MGy Total Ionizing Dose Environments

The Total Ionizing Dose (TID) hardness of digital color Camera-on-a-Chip (CoC) building blocks is explored in the Multi-MGy range using 60Co gamma-ray irradiations. The performances of the following CoC subcomponents are studied: radiation hardened (RH) pixel and photodiode designs, RH readout chain, Color Filter Arrays (CFA) and column RH Analog-to-Digital Converters (ADC). Several radiation hardness improvements are reported (on the readout chain and on dark current). CFAs and ADCs degradations appear to be very weak at the maximum TID of 6 MGy(SiO2), 600 Mrad. In the end, this study demonstrates the feasibility of a MGy rad-hard CMOS color digital camera-on-a-chip, illustrated by a color image captured after 6 MGy(SiO2) with no obvious degradation. An original dark current reduction mechanism in irradiated CMOS Image Sensors is also reported and discussed

Neurons in the Nucleus papilio contribute to the control of eye movements during REM sleep

Rapid eye movements (REM) are characteristic of the eponymous phase of sleep, yet the underlying motor commands remain an enigma. Here, we identified a cluster of Calbindin-D28K-expressing neurons in the Nucleus papilio (NPCalb), located in the dorsal paragigantocellular nucleus, which are active during REM sleep and project to the three contralateral eye-muscle nuclei. The firing of opto-tagged NPCalb neurons is augmented prior to the onset of eye movements during REM sleep. Optogenetic activation of NPCalb neurons triggers eye movements selectively during REM sleep, while their genetic ablation or optogenetic silencing suppresses them. None of these perturbations led to a change in the duration of REM sleep episodes. Our study provides the first evidence for a brainstem premotor command contributing to the control of eye movements selectively during REM sleep in the mammalian brain