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TimeGate: Conditional Gating of Segments in Long-range Activities [article]

Noureldien Hussein, Mihir Jain, Babak Ehteshami Bejnordi
2020 arXiv   pre-print
We propose TimeGate, along with a novel conditional gating module, for sampling the most representative segments from the long-range activity.  ...  Consequently, TimeGate is better suited for long-range activities, where the importance of a segment heavily depends on the video context.TimeGate reduces the computation of existing CNNs on three benchmarks  ...  Context-Conditional Gating When selecting the timesteps of long-range activities, TimeGate is conditioned on both the segment and its context.  ... 
arXiv:2004.01808v1 fatcat:bk3osbs4x5gjtb7alg4qbpppwm

Using a simulation approach to optimize time-domain diffuse correlation spectroscopy measurement on human head

Lina Qiu, Huiyi Cheng, Alessandro Torricelli, Jun Li
2018 Neurophotonics  
The simulations show that with an acceptable input power of light, the combinations of SD distance ranging from 0 to 15 mm, gate opening time at 700 to 800 ps, and gate width of 800 ps are optimal for  ...  SD distance ranging from 0 to 45 mm, gate opening time from 400 to 1000 ps, and gate width from 50 to 3000 ps are considered.  ...  Table 2 shows the diffusion coefficient D B of scatterers in the baseline and stimulation conditions. 19, 20 During the stimulation (or activation), the dynamics in cortex (including GM and WM) was  ... 
doi:10.1117/1.nph.5.2.025007 pmid:29795775 pmcid:PMC5949562 fatcat:2hkc5nluhnfdrlzdfz3adyrxdu

Visualising apoptosis in live zebrafish using fluorescence lifetime imaging with optical projection tomography to map FRET biosensor activity in space and time

Natalie Andrews, Marie-Christine Ramel, Sunil Kumar, Yuriy Alexandrov, Douglas J. Kelly, Sean C. Warren, Louise Kerry, Nicola Lockwood, Antonina Frolov, Paul Frankel, Laurence Bugeon, James McGinty (+2 others)
2016 Journal of Biophotonics  
Apoptosis, or programmed cell death, is mapped in 3-D by imaging the activity of a FRET biosensor that is cleaved by Caspase 3, which is a key effector of apoptosis.  ...  FLIM OPT is shown here to enable apoptosis to be monitored over time, in live zebrafish larvae via changes in Caspase 3 activation following gamma irradiation at 24 hours post fertilisation.  ...  K011561/1), the UK Biotechnology and Biological Sciences Research Council (BBSRC BB/H00713X/1) and the Wellcome Trust (095931/Z/11/Z) Natalie Andrews acknowledges a Ph.D. studentship from the Institute of  ... 
doi:10.1002/jbio.201500258 pmid:26753623 pmcid:PMC4858816 fatcat:y5pafntldzbipewrkgpzfsq27i

Auditory processing in children: Role of working memory and lexical ability in auditory closure

Naveen K. Nagaraj, Beula M. Magimairaj, Susan Nittrouer
2020 PLoS ONE  
Children's working memory capacity (WMC), attention, lexical knowledge, and retrieval from long-term memory (LTM) abilities were also measured to model their role in auditory closure ability.  ...  In essence, children were given only 50% of speech information and asked to repeat the complete word or sentence.  ...  Interrupted speech with filler noise sounds continuous, and this illusion of perceived speech continuity is expected to activate a larger lexical network in listeners' long-term memory [53] .  ... 
doi:10.1371/journal.pone.0240534 pmid:33147602 fatcat:qricrdbqpjdcxln2wr6c33ev3a

An 8-Tap CMOS Lock-In Pixel Image Sensor for Short-Pulse Time-of-Flight Measurements

Yuya Shirakawa, Keita Yasutomi, Keiichiro Kagawa, Satoshi Aoyama, Shoji Kawahito
2020 Sensors  
The proposed pixel for the short-pulse TOF measurements has seven consecutive time-gating windows, each of which has the width of 6 ns, which is advantageous for high-resolution range imaging, particularly  ...  The maximum non-linearity error of 1.56%FS for the range of 1–6.4 m and the depth resolution of 6.4 mm was obtained at 6.2 m using the DATA technique.  ...  Conflicts of Interest: The authors declare no conflict of interest.  ... 
doi:10.3390/s20041040 pmid:32075170 pmcid:PMC7070250 fatcat:z7abpp7nejfsxnzwuwpbup5pxm

Improved sensitivity to cerebral hemodynamics during brain activation with a time-gated optical system: analytical model and experimental validation

Juliette Selb, Jonathan J. Stott, Maria Angela Franceschini, A. Gregory Sorensen, David A. Boas
2005 Journal of Biomedical Optics  
Finally, we use the timegated measurements to resolve in depth the brain activation during the motor stimulus.  ...  We study the contrast-to-noise ratio and the contrast-to-background ratio as a function of the activation depth and of the source-detector separation.  ...  ., for the use of their TD instrumentation. We would like to thank Quan Zhang for his help in estimating the experimental CW noise, and Theodore J.  ... 
doi:10.1117/1.1852553 pmid:15847579 fatcat:thmv4yv7gbc7zlrrdjz7rdouiq

Validation of aClostridiumEndospore Viability Assay and Analysis of Greenland Ices and Atacama Desert Soils

Wan-Wan Yang, Adrian Ponce
2011 Applied and Environmental Microbiology  
, enables enumeration of resultant green Tb3+-DPA luminescent spots as GCEs with time-gated luminescence microscopy.  ...  in Greenland ices and Atacama Desert soils.  ...  The research described in this paper was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.  ... 
doi:10.1128/aem.01966-10 pmid:21296951 pmcid:PMC3067429 fatcat:xrjncpax5fgtxezmmat7ymwfcq

FLIM FRET Technology for Drug Discovery: Automated Multiwell-Plate High-Content Analysis, Multiplexed Readouts and Application in Situ

Sunil Kumar, Dominic Alibhai, Anca Margineanu, Romain Laine, Gordon Kennedy, James McGinty, Sean Warren, Douglas Kelly, Yuriy Alexandrov, Ian Munro, Clifford Talbot, Daniel W. Stuckey (+15 others)
2011 ChemPhysChem  
The assistance of the Human Biomaterials Resource Centre of Imperial College Healthcare NHS Trust in obtaining tissue for this study is gratefully acknowledged.  ...  D.A., D.K., S.W. and R.L. acknowledge PhD studentships from the Institute of Chemical Biology EPSRC-funded Doctoral Training Centre.  ...  Time-gated imaging was provided by a gated optical intensifier (Kentech Instruments, model HRI) that was customised to provide time-gates as long as 3 ns.  ... 
doi:10.1002/cphc.201000874 pmid:21337485 pmcid:PMC3084521 fatcat:ejdkpddaczaqzdfflgjk2dbmfu

Imaging of Lipids in Microalgae with Coherent Anti-Stokes Raman Scattering Microscopy

Lillie Cavonius, Helen Fink, Juris Kiskis, Eva Albers, Ingrid Undeland, Annika Enejder
2015 Plant Physiology  
As an alternative strategy to solvent-and label-based lipid quantification techniques, we introduce time-gated coherent anti-Stokes Raman scattering (CARS) microscopy for monitoring lipid contents in living  ...  Intracellular lipid droplet synthesis was followed in Phaeodactylum tricornutum algae grown under (1) light/nutrient-replete (control [Ctrl]), (2) light-limited (LL), and (3) nitrogenstarved (NS) conditions  ...  The limit of detection was estimated as 0.1 mg mL 21 under the described running conditions (100 pg injected on column).  ... 
doi:10.1104/pp.114.252197 pmid:25583924 pmcid:PMC4348760 fatcat:gvbj7uzqszcudlgaklmevxdwju

Data Processing Approaches on SPAD-based Flash LiDAR Systems: A Review

Gongbo Chen, Christian Wiede, Rainer Kokozinski
2020 IEEE Sensors Journal  
Light detection and ranging (LiDAR) sensors are attracting attention due to their unique advantages in terms of radial distance resolution and detection range.  ...  The principles, limitations, and challenges of these methods are discussed in detail and the criteria for evaluation of time-correlated histograms in ADAS are proposed.  ...  Among these technologies, LiDAR provides high range resolution and long depth range [5] - [7] .  ... 
doi:10.1109/jsen.2020.3038487 fatcat:6fbuubj52zanfa2kj7kf5p2izy

Colloidal nanoparticles as advanced biological sensors

P. D. Howes, R. Chandrawati, M. M. Stevens
2014 Science  
We review the state of the art in nanoparticle development, surface chemistry, and biosensing mechanisms, discussing how a range of technologies are contributing toward commercial and clinical translation  ...  Recent examples of success include the ultrasensitive detection of cancer biomarkers in human serum and in vivo sensing of methyl mercury.  ...  For such applications, nanoparticle biosensors must be stable enough to withstand long-term storage and fluctuations in environmental conditions.  ... 
doi:10.1126/science.1247390 pmid:25278614 fatcat:xsu7krgjvfebljfed4wfr7q7pa

Time-gated Fourier-domain optical coherence tomography

Matthew S. Muller, Paul J. Webster, James M. Fraser
2007 Optics Letters  
The i nonlinear effect used in the current time-gated OCT design is sum-frequency generation, which provides an additional advantage of imaging at near infrared (1280 nm) wavelengths, used for long penetration  ...  These conditions allow for the creation of a user-controlled time gate that restricts the light backscattered from the sample to a narrow (∼100 micrometres) depth field of view prior to detection.  ...  Presently, the most mature clinical application of OCT imaging is the diagnosis and monitoring of ocular diseases in the posterior segment of the eye [8] .  ... 
doi:10.1364/ol.32.003336 pmid:18026299 fatcat:uicrq2pdgbfpxicx65nasfej44

FRET and LRET Biosensors for Cell-based Imaging and Screening of Rac1 Activation [article]

Ha Pham, Mona Hoseini Soflaee, Andrei V Karginov, Lawrence Miller
2021 bioRxiv   pre-print
Rac1 is a key regulator of several cell signaling pathways and dysregulated Rac1 activation has been implicated in cancer.  ...  gains in dynamic range that increased with linker length (up to 1200%).  ...  The strong influence in LRET biosensors may be due to the long distance of LRET, which causes high baseline signals and requires a long rigid linker for extended conformation in the Off state.  ... 
doi:10.1101/2021.06.25.449998 fatcat:v3dsvmdog5c6hbykyuzbk2e7r4

Assessment of soot particle-size imaging with LII at Diesel engine conditions

E. Cenker, K. Kondo, G. Bruneaux, T. Dreier, T. Aizawa, C. Schulz
2015 Applied physics B  
Experiments were conducted in a high-temperature high-pressure constant-volume precombustion vessel under the Engine Combustion Network's (ECN) "Spray A" conditions at 61-68 bar with additional parametric  ...  The method is based on evaluating gated LII signals acquired with two cameras consecutively after the laser pulse and using LII modeling to deduce the particle size from the ratio of local signals.  ...  For all these conditions, a long injection duration of 6 ms (longer than the Spray A standard of 1.5 ms) is used to enable an analysis of the soot cloud under quasisteady conditions. [19] .  ... 
doi:10.1007/s00340-015-6106-0 fatcat:ruscybiuhfgjhbm6zh6uhottl4

In vitro and in vivo phasor analysis of stoichiometry and pharmacokinetics using short lifetime near-infrared dyes and time-gated imaging

Sez-Jade Chen, Nattawut Sinsuebphon, Alena Rudkouskaya, Margarida Barroso, Xavier Intes, Xavier Michalet
2018 Journal of Biophotonics  
representation of complex fluorescence intensity decays obtained with pulsed laser excitation and time-gated camera imaging.  ...  We then extend it to dynamic imaging of the pharmacokinetics of transferrin engagement with the transferrin receptor in live mice, elucidating the kinetics of differential transferrin accumulation in specific  ...  The measurable changes in lifetimes from one condition to the next range from 17 to 43 ps, with a typical SD within each measurement of 10 ps.  ... 
doi:10.1002/jbio.201800185 pmid:30421551 pmcid:PMC6559731 fatcat:wdkyvw6xqrbvhefjzi5naxicau
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