Generation of internal stress and its effects

Internal stresses may be generated continually in many polycrystalline materials. Their existence is manifested by changes in crystal defect concentration and arrangement, by surface observations, by macroscopic shape changes and particularly by alteration of mechanical properties when external stresses are simultaneously imposed

Cypress: A High Yielding, High Quality Long-Grain Rice Variety

Cypress is a high-yielding, early-maturing, semidwarf, long-grain rice variety with excellent grain quality. This bulletin includes information on the history, characteristics, cultural management and pest reaction of Cypress.https://digitalcommons.lsu.edu/agcenter_bulletins/1011/thumbnail.jp

Thin-film silicon detectors for particle detection

Integrated particle sensors have been developed using thin-film on ASIC technology. For this purpose, hydrogenated amorphous silicon diodes, in various configurations, have been optimized for particle detection. These devices were first deposited on glass substrates to optimize the material properties and the dark current of very thick diodes (with thickness up to 50 μm). Corresponding diodes were later directly deposited on CMOS readout chips. These integrated particle sensors have been characterized using light pulse illumination and beta particle irradiation from 63Ni and 90Sr sources. Direct detection of single low- and high-energy beta particles have been demonstrated. The application of this new integrated particle sensor concept for medical imaging is also discussed

Extensive remodeling of DC function by rapid maturation-induced transcriptional silencing.

The activation, or maturation, of dendritic cells (DCs) is crucial for the initiation of adaptive T-cell mediated immune responses. Research on the molecular mechanisms implicated in DC maturation has focused primarily on inducible gene-expression events promoting the acquisition of new functions, such as cytokine production and enhanced T-cell-stimulatory capacity. In contrast, mechanisms that modulate DC function by inducing widespread gene-silencing remain poorly understood. Yet the termination of key functions is known to be critical for the function of activated DCs. Genome-wide analysis of activation-induced histone deacetylation, combined with genome-wide quantification of activation-induced silencing of nascent transcription, led us to identify a novel inducible transcriptional-repression pathway that makes major contributions to the DC-maturation process. This silencing response is a rapid primary event distinct from repression mechanisms known to operate at later stages of DC maturation. The repressed genes function in pivotal processes--including antigen-presentation, extracellular signal detection, intracellular signal transduction and lipid-mediator biosynthesis--underscoring the central contribution of the silencing mechanism to rapid reshaping of DC function. Interestingly, promoters of the repressed genes exhibit a surprisingly high frequency of PU.1-occupied sites, suggesting a novel role for this lineage-specific transcription factor in marking genes poised for inducible repression

BMC Nephrol

BACKGROUND: To describe the quality of life of adolescents initiating haemodialysis, to determine the factors associated with quality of life, and to assess coping strategies and their impact on quality of life. METHODS: All adolescents initiating haemodialysis between September 2013 and July 2015 in French paediatric haemodialysis centres were included. Quality of life data were collected using the "Vecu et Sante Percue de l'Adolescent et l'Enfant" questionnaire, and coping data were collected using the Kidcope questionnaire. Adolescent's quality of life was compared with age- and sex-matched French control. RESULTS: Thirty-two adolescents were included. Their mean age was 13.9 +/- 2.0 years. The quality of life score was lowest in leisure activities and highest in relationships with medical staff. Compared with the French control, index, energy-vitality, relationships with friends, leisure activities and physical well-being scores were significantly lower in haemodialysis population. In multivariate analyses, active coping was positively associated with quality of life and especially with energy-vitality, relationships with parents and teachers, and school performance. In contrast, avoidant and negative coping were negatively associated with energy-vitality, psychological well-being and body image for avoidant coping, and body image and relationships with medical staff for negative coping. CONCLUSIONS: The quality of life of haemodialysis adolescents, and mainly the dimensions of leisure activities, physical well-being, relationships with friends and energy-vitality, were significantly altered compared to that of the French population. The impact of coping strategies on quality of life seems to be important. Given the importance of quality of life and coping strategies in adolescents with chronic disease, health care professionals should integrate these aspects into care management

Radiation hardness of amorphous silicon particle sensors

Radiation tests of 32 μm thick hydrogenated amorphous silicon n-i-p diodes have been performed using a high- energy 24 GeV proton beam up to fluences of 2x1016 protons/cm2. The results are compared to irradiation of similar 1 μm and 32 μm thick n-i-p diodes using a proton beam of 405 keV at a fluence of 3x1013 protons/cm2. All samples exhibited a drop of the photoconductivity and an increase in the dark leakage current under both high and low energy proton irradiation. An almost full recovery of the device performance was observed after a subsequent thermal annealing

Quantum efficiency measurement of n–i–p a-Si:H photodiode array on CMOS circuit for positron emission tomography (PET)

Detection of scintillation light from LSO (Lutetiumoxyorthosilicate) crystals used in positron emission tomography (PET) is traditionally based on photo- multipliers. The proposal is to develop a novel photo- sensor, which is based on vertically integrating an hydrogenated amorphous silicon (a-Si:H) film on a pixel readout chip. The a-Si:H film is deposited with a n-i-p diode structure. The ASIC (Application Specific Integrated Circuit) performs both signal amplification and readout processing. The advantage of such an approach is the extremely compact and low-cost design, together with ultra- low noise signal retrieval. In addition the a-Si:H offers the technological advantage of direct deposition on the wafer thanks to the low deposition temperature. The article presents the results of quantum efficiency measured on different types of a-Si:H photodiodes deposited on glass (DC measurement) and CMOS circuit (AC measurement). Quantum Efficiency (QE) up to 80% has been measured at the wavelength of interest for the optimized photodiodes. © 2007 Elsevier B.V. All rights reserved

Characterization of a thick layer a-Si : H pixel detector with TFA technology using a scanning electron microscope

The electron beam induced current (EBIC) technique was used to characterize a 32 μm thick hydrogenated amorphous silicon n-i-p diode deposited on top of an ASIC, containing several channels of active feedback pre-amplifiers (AFP) with peaking time of 5 ns. The homogeneity of the sample together with the edge effects induced by the unevenness of the ASIC substrate were studied with low doses of 10-30 keV electron beam. The degradation of a-Si:H pixel detectors was measured with intense electron beam. Their charge collection and transient time were characterized with a 660 nm pulsed laser before and after the thermal annealing. All the diodes show approximately a full recovery of charge collection after thermal annealing. © 2006 Elsevier B.V. All rights reserved

Reactive synthesis of Ti-Al intermetallics during microwave heating in an E-field maximum

The time-resolved X-ray diffraction synchrotron radiation technique was used in combination with E-field microwave heating to study in situ the kinetics of intermetallic phase formation in the Ti-Al system. The reaction of Ti with Al is triggered by the melting and spreading of Al onto the surface of Ti particles. The tetragonal TiAl 3 phase is the primary reaction product, formed by instantaneous nucleation at the interface between the unreacted Ti cores and the Al melt. The growth of TiAl 3 layers is diffusion-controlled. These preliminary results demonstrate that microwave heating can be used to rapidly synthesise intermetallic phases from high-purity elemental powders. © 2010 Elsevier B.V. All rights reserved.This work has been supported by the Swiss National Science Foundation (Grant 20PA21E-129193).Vaucher, S.; Stir, M.; Ishizaki, K.; Catalá Civera, JM.; Nicula, R. (2011). Reactive synthesis of Ti-Al intermetallics during microwave heating in an E-field maximum. Thermochimica Acta. 522(1):151-154. doi:10.1016/j.tca.2010.11.026S151154522