Ultra-long-time (0.8 s) characterization of laser phase noise with high temporal resolution (800 ps) based on heterodyne reception with FPGA data acquisition

Author(s):  
Hayato Kiwata ◽  
Masahiro Kikuta ◽  
Masahiro Shigihara ◽  
Koji Igarashi
2010 ◽  
Vol 6 (2) ◽  
pp. 43 ◽  
Author(s):  
Andreas H Mahnken ◽  

Over the last decade, cardiac computed tomography (CT) technology has experienced revolutionary changes and gained broad clinical acceptance in the work-up of patients suffering from coronary artery disease (CAD). Since cardiac multidetector-row CT (MDCT) was introduced in 1998, acquisition time, number of detector rows and spatial and temporal resolution have improved tremendously. Current developments in cardiac CT are focusing on low-dose cardiac scanning at ultra-high temporal resolution. Technically, there are two major approaches to achieving these goals: rapid data acquisition using dual-source CT scanners with high temporal resolution or volumetric data acquisition with 256/320-slice CT scanners. While each approach has specific advantages and disadvantages, both technologies foster the extension of cardiac MDCT beyond morphological imaging towards the functional assessment of CAD. This article examines current trends in the development of cardiac MDCT.


2018 ◽  
Vol 176 ◽  
pp. 01017 ◽  
Author(s):  
Giovanni Martucci ◽  
Valentin Simeonov ◽  
Ludovic Renaud ◽  
Alexander Haefele

RAman Lidar for Meteorological Observations (RALMO) is operated at MeteoSwiss and provides continuous measurements of water vapor and temperature since 2010. While the water vapor has been acquired by a Licel acquisition system since 2008, the temperature channels have been migrated to a Fastcom P7888 acquisition system, since August 2015. We present a characterization of this new acquisition system, namely its dead-time, desaturation, temporal stability of the Pure Rotational Raman signals and the retrieval of the PRR-temperature.


2016 ◽  
Vol 43 (6Part1) ◽  
pp. 2802-2806 ◽  
Author(s):  
Rodney D. Wiersma ◽  
Bradley P. McCabe ◽  
Andrew H. Belcher ◽  
Patrick J. Jensen ◽  
Brett Smith ◽  
...  

2016 ◽  
Vol 8 (7) ◽  
pp. 570 ◽  
Author(s):  
Cécile Cazals ◽  
Sébastien Rapinel ◽  
Pierre-Louis Frison ◽  
Anne Bonis ◽  
Grégoire Mercier ◽  
...  

2021 ◽  
Author(s):  
Shixian Wen ◽  
Allen Yin ◽  
Po-He Tseng ◽  
Laurent Itti ◽  
Mikhail Lebedev ◽  
...  

Abstract Motor brain machine interfaces (BMI) directly link the brain to artificial actuators and have the potential to mitigate severe body paralysis caused by neurological injury or disease. Most BMI systems involve a decoder that analyzes neural spike counts to infer movement intent. However, many classical BMI decoders 1) fail to take advantage of temporal patterns of spike trains, possibly over long time horizons; 2) are insufficient to achieve good BMI performance at high temporal resolution, as the underlying Gaussian assumption of decoders based on spike counts is violated. Here, we propose a new statistical feature that represents temporal patterns or temporal codes of spike events with richer description - wavelet average coefficients (WAC) - to be used as decoder input instead of spike counts. We constructed a wavelet decoder framework by using WAC features with a sliding-window approach, and compared the resulting decoder against classical decoders (Wiener and Kalman family) using spike count features. We found that the sliding-window approach boosts decoding temporal resolution, and using WAC features significantly improves decoding performance over using spike count features.


2021 ◽  
Author(s):  
Jessica Cartwright ◽  
Alexander D. Fraser

Abstract. Maps of backscatter anisotropy parameters from the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT) Advanced Scatterometer (ASCAT), a C-band fan-beam scatterometer, contain unique and valuable data characterising the surface and subsurface of various cryospheric elements, including sea ice and ice sheets. The computational expense and considerable complexity required to produce parameter maps from the raw backscatter data inhibits the wider adoption of ASCAT data. Here, backscatter anisotropy parameter maps gridded at a resolution of 12.5 km per pixel are made available to the community in order to facilitate the exploitation of these parameters for cryospheric applications. These maps have been calculated from the EUMETSAT Level 1B sigma0 product acquired from ASCAT on board MetOp-A, MetOp-B and MetOp-C. The dataset is unique in that it prioritises anisotropy characterisation over temporal resolution, and combines ASCAT data from multiple platforms. The parameterisation chosen assumes a linear falloff of backscatter with incidence angle and a 4th order Fourier series parameterisation of azimuth angle anisotropy. The product (Fraser and Cartwright, 2021) is available at https://doi.org/10.26179/5dd60df7469e2 presented on three time scales depending on orbital platform availability: 5-day (2007 to present – MetOp-A only – suitable for users requiring a long time-series), 2-day (2013 to present – MetOp-A and -B), and 1-day resolution (2019 – present – MetOp -A, -B and -C – suitable for users needing both high temporal resolution and detailed anisitropy characterisation).


2021 ◽  
Author(s):  
Darawan Rinchai ◽  
Sara Deola ◽  
Gabriele Zoppoli ◽  
Basirudeen Syed Ahamed Kabeer ◽  
Sara Ahmad Taleb ◽  
...  

Knowledge of the factors contributing to the development of protective immunity after vaccination with COVID-19 mRNA vaccines is fragmentary. Thus we employed high-temporal-resolution transcriptome profiling and in-depth characterization of antibody production approaches to investigate responses to COVID-19 mRNA vaccination. There were marked differences in the timing and amplitude of the responses to the priming and booster doses. Notably, two distinct interferon signatures were identified, that differed based on their temporal patterns of induction. The first signature (S1), which was preferentially induced by type I interferon, peaked at day 2 post-prime and at day 1 post-boost, and in both instances was associated with subsequent development of the antibody response. In contrast, the second interferon signature (S2) peaked at day 1 both post-prime and post-boost but was found to be potently induced only post-boost, where it coincided with a robust inflammation peak. Notably, we also observed post-prime-like (S1++,S20/+) and post-boost-like (S1++,S2++) patterns of interferon response among COVID-19 patients. A post-boost-like signature was observed in most severely ill patients at admission to the intensive care unit and was associated with a shorter hospital stay. Interestingly, severely ill patients who stayed hospitalized the longest showed a peculiar pattern of interferon induction (S1-/0,S2+), that we did not observe following the administration of mRNA vaccines. In summary, high temporal resolution profiling revealed an elaborate array of immune responses elicited by priming and booster doses of COVID-19 mRNA vaccines. Furthermore, it contributed to the identification of distinct interferon-response phenotypes underpinning vaccine immunogenicity and the course of COVID-19 disease.


2017 ◽  
Vol 468 ◽  
pp. 63-74 ◽  
Author(s):  
Michael Weber ◽  
Jasper A. Wassenburg ◽  
Klaus Peter Jochum ◽  
Sebastian F.M. Breitenbach ◽  
Jessica Oster ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document