606 research outputs found
Auto-zero stabilized CMOS amplifiers for very low voltage or current offset
In this paper, we present two amplifiers designed in CMOS technology and including an auto-zero architecture for very low offset control
Development of a DMILL radhard multiplexer for the ATLAS Glink optical link and radiation test with a custom Bit ERror Tester
A high speed digital optical data link has been developed for the front-end readout of the ATLAS electromagnetic calorimeter. It is based on a commercial serialiser commonly known as Glink, and a vertical cavity surface emitting laser. To be compatible with the data interface requirements, the Glink must be coupled to a radhard multiplexer that has been designed in DMILL technology to reduce the impact of neutron and gamma radiation on the link performance. This multiplexer features a very severe timing constraints related both to the front-end board output data and the Glink control and input signals. The full link has been successfully neutron and proton radiation tested by means of a custom bit error tester. (7 refs)
A low power 12-bit and 25-MS/s pipelined ADC for the ILC/Ecal integrated readout
International audienc
Study on the origin of cacao swollen shoot virus and its dispersal on cacao trees in West Africa [W112]
Cacao swollen shoot virus (CSSV) is a member of the family Caulimoviridae, genus Badnavirus naturally transmitted to Theobroma cacao by several mealybug species. The virus, restricted to West Africa whereas the cacao tree originates from the Western Hemisphere, could therefore most probably have an indigenous origin on the West African subcontinent. The disease has caused enormous economic damage in Ghana since the1930s but was only restricted to small areas in Togo and Côte d'Ivoire until recently. Now, renewed outbreaks in the main producing areas in Côte d'Ivoire, Ghana and Togo cause serious problems. CSSV populations in West African countries are genetically structured in twelve groups according to the diversity in the first part of ORF3 and the 20% threshold of nucleotide divergence. However, according to ICTV recommendations taking into account the nucleotide diversity in the RTAse region, we could describe seven different species. The high variability observed within CSSV populations compared to its very short evolutionary history on cocoa trees, suggests the existence of many emergences from native hosts to cacao trees in the various countries of West Africa. Moreover, based on the geographical dispersal of the different species, we could propose the existence at different times of parallel emergences in each of the West African countries. As a perspective of this work, a newly accepted project funded by European Cocoa Association will be presented. (Texte intégral
Study on the origin of cacao swollen shoot virus and its dispersal on cacao trees in West Africa
BACKGROUND and OBJECTIVES Cacao swollen shoot virus (CSSV) is a member of the family Caulimoviridae, genus Badnavirus naturally transmitted to Theobroma cacao by several mealybug species. Typical symptoms of the disease on cocoa trees are red vein banding of young leaves, mosaic on older leaves and swelling of the orthotropic shoots. The virus, restricted to West Africa whereas the cacao tree originates from the Western Hemisphere, could therefore most probably have an indigenous origin on the West African subcontinent. The disease has caused enormous economic damage in Ghana since the1930s but was only restricted to small areas in Togo and Côte d'Ivoire until recently. Now, renewed outbreaks in the main producing areas in Côte d'Ivoire, Ghana and Togo cause serious problems. The knowledge of the viral biodiversity in the different outbreaks will in turn help to provide a better understanding of the development of the epidemics, and of the evolution of viral populations and may permit to retrace the emergence and dispersal of CSSV. MATERIAL and METHODS Prospections were made over several successive years in Ivory Coast, Togo and Ghana. Virus variability was studied by PCR amplification with CSSV primers, direct sequencing, sequence alignment and phylogenetic studies. RESULTS CSSV diversity is genetically structured in twelve groups according to the diversity in the first part of ORF3 and the 20% threshold of nucleotide divergence. However, according to ICTV recommendations which consider the nucleotide diversity in the RTAse region, we could describe at least seven different species. CONCLUSIONS The high variability observed within CSSV populations compared to its very short evolutionary history on cocoa trees, suggests the existence of many emergences from native hosts to cacao trees in the various countries of West Africa. Moreover, based on the geographical dispersal of the different species, we could propose the existence at different times of parallel emergences in each of the West African countries. (Texte intégral
A Digitally Calibrated 12 bits 25 MS/s Pipelined ADC with a 3 input multiplexer for CALICE Integrated Readout
The necessity of full integrated electronics readout for the next ILC ECAL presents many challenges for low power mixed signal design. The analog to digital converter is a critical stage for the system going from the very front-end stages to digital memories. We present here a high speed converter configuration designed to multiplex 3 analog channels through one analog to digital converter. It is a first step for a multiplexed 64 channel design. A CMOS 0.35μm process is used. The dynamic range is 2V over a 3.3V power supply, and the total power dissipation at 25 MHz is approximately 40mW. An analog power management is included to allow a fast switching into a standby mode that reduces the DC power dissipation by a ratio of three orders of magnitude (1/1000)
Knowledge graph prediction of unknown adverse drug reactions and validation in electronic health records
Unknown adverse reactions to drugs available on the market present a significant health risk and limit accurate judgement of the cost/benefit trade-off for medications. Machine learning has the potential to predict unknown adverse reactions from current knowledge. We constructed a knowledge graph containing four types of node: drugs, protein targets, indications and adverse reactions. Using this graph, we developed a machine learning algorithm based on a simple enrichment test and first demonstrated this method performs extremely well at classifying known causes of adverse reactions (AUC 0.92). A cross validation scheme in which 10% of drug-adverse reaction edges were systematically deleted per fold showed that the method correctly predicts 68% of the deleted edges on average. Next, a subset of adverse reactions that could be reliably detected in anonymised electronic health records from South London and Maudsley NHS Foundation Trust were used to validate predictions from the model that are not currently known in public databases. High-confidence predictions were validated in electronic records significantly more frequently than random models, and outperformed standard methods (logistic regression, decision trees and support vector machines). This approach has the potential to improve patient safety by predicting adverse reactions that were not observed during randomised trials
Development of a front end ASIC for Dark Matter directional detection with MIMAC
A front end ASIC (BiCMOS-SiGe 0.35 \mum) has been developed within the
framework of the MIMAC detector project, which aims at directional detection of
non-baryonic Dark Matter. This search strategy requires 3D reconstruction of
low energy (a few keV) tracks with a gaseous \muTPC. The development of this
front end ASIC is a key point of the project, allowing the 3D track
reconstruction. Each ASIC monitors 16 strips of pixels with charge
preamplifiers and their time over threshold is provided in real time by current
discriminators via two serializing LVDS links working at 320 MHz. The charge is
summed over the 16 strips and provided via a shaper. These specifications have
been chosen in order to build an auto triggered electronics. An acquisition
board and the related software were developed in order to validate this
methodology on a prototype chamber. The prototype detector presents an anode
where 2 x 96 strips of pixels are monitored.Comment: 12 pages, 10 figure
A very low power and low signal 5 bit 50 M samples/s double sampling pipelined ADC for Monolithic Active Pixel Sensors in high energy physics and biomedical imaging applications
International audienc
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