scholarly journals GlucoCEST imaging with on-resonance variable delay multiple pulse (onVDMP) MRI

2018 ◽  
Vol 81 (1) ◽  
pp. 47-56 ◽  
Author(s):  
Xiang Xu ◽  
Jiadi Xu ◽  
Kannie W.Y. Chan ◽  
Jing Liu ◽  
Huanling Liu ◽  
...  
Keyword(s):  
Variable Delay ◽  
Multiple Pulse

scholarly journals Separating fast and slow exchange transfer and magnetization transfer using off-resonance variable-delay multiple-pulse (VDMP) MRI

2018 ◽  
Vol 80 (4) ◽  
pp. 1568-1576 ◽  
Author(s):  
Lin Chen ◽  
Xiang Xu ◽  
Haifeng Zeng ◽  
Kannie W.Y. Chan ◽  
Nirbhay Yadav ◽  
...  
Keyword(s):  
Magnetization Transfer ◽  
Variable Delay ◽  
Multiple Pulse ◽  
Slow Exchange

scholarly journals D-Glucose uptake and clearance in the tauopathy Alzheimer’s disease mouse brain detected by on-resonance variable delay multiple pulse MRI

2020 ◽  
pp. 0271678X2094126
Author(s):  
Lin Chen ◽  
Zhiliang Wei ◽  
Kannie WY Chan ◽  
Yuguo Li ◽  
Kapil Suchal ◽  
...  
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Glucose Uptake ◽  
Glucose Transporter ◽  
Neurofibrillary Tangle ◽  
Cost Effective ◽  
Variable Delay ◽  
Wild Type ◽  
Multiple Pulse ◽  
Model Of Alzheimer’S Disease

In this study, we applied on-resonance variable delay multiple pulse (onVDMP) MRI to study D-glucose uptake in a mouse model of Alzheimer’s disease (AD) tauopathy and demonstrated its feasibility in discriminating AD mice from wild-type mice. The D-glucose uptake in the cortex of AD mice (1.70 ± 1.33%) was significantly reduced compared to that of wild-type mice (5.42 ± 0.70%, p = 0.0051). Also, a slower D-glucose uptake rate was found in the cerebrospinal fluid (CSF) of AD mice (0.08 ± 0.01 min−1) compared to their wild-type counterpart (0.56 ± 0.1 min−1, p < 0.001), which suggests the presence of an impaired glucose transporter on both blood–brain and blood–CSF barriers of these AD mice. Clearance of D-glucose was observed in the CSF of wild-type mice but not AD mice, which suggests dysfunction of the glymphatic system in the AD mice. The results in this study indicate that onVDMP MRI could be a cost-effective and widely available method for simultaneously evaluating glucose transporter and glymphatic function of AD. This study also suggests that tau protein affects the D-glucose uptake and glymphatic impairment in AD at a time point preceding neurofibrillary tangle pathology.

Control by Pyragas method with variable delay: from simple models to experiments

2014 ◽  
Vol 1 ◽  
pp. 679-682
Author(s):  
Aleksandar Gjurchinovski ◽  
Thomas Jüngling ◽  
Viktor Urumov
Keyword(s):  
Variable Delay ◽  
Simple Models

A Feed-Forward Time Amplifier Using a Phase Detector and Variable Delay Lines

2013 ◽  
Vol E96.C (6) ◽  
pp. 920-922 ◽  
Author(s):  
Kiichi NIITSU ◽  
Naohiro HARIGAI ◽  
Takahiro J. YAMAGUCHI ◽  
Haruo KOBAYASHI
Keyword(s):  
Phase Detector ◽  
Variable Delay ◽  
Delay Lines ◽  
Feed Forward ◽  
Time Amplifier

scholarly journals Perceiving numerosity does not cause automatic shifts of spatial attention

2021 ◽  
Author(s):  
Michele Pellegrino ◽  
Mario Pinto ◽  
Fabio Marson ◽  
Stefano Lasaponara ◽  
Fabrizio Doricchi
Keyword(s):  
Spatial Attention ◽  
Colour Change ◽  
Simultaneous Presentation ◽  
Variable Delay ◽  
Large Magnitude ◽  
Small Magnitude ◽  
Spatial Component ◽  
Speed Up ◽  
The Right

AbstractIt is debated whether the representation of numbers is endowed with a directional-spatial component so that perceiving small-magnitude numbers triggers leftward shifts of attention and perceiving large-magnitude numbers rightward shifts. Contrary to initial findings, recent investigations have demonstrated that centrally presented small-magnitude and large-magnitude Arabic numbers do not cause leftward and rightward shifts of attention, respectively. Here we verified whether perceiving small or large non-symbolic numerosities (i.e., clouds of dots) drives attention to the left or the right side of space, respectively. In experiment 1, participants were presented with central small (1, 2) vs large-numerosity (8, 9) clouds of dots followed by an imperative target in the left or right side of space. In experiment 2, a central cloud of dots (i.e., five dots) was followed by the simultaneous presentation of two identical dot-clouds, one on the left and one on the right side of space. Lateral clouds were both lower (1, 2) or higher in numerosity (8, 9) than the central cloud. After a variable delay, one of the two lateral clouds turned red and participants had to signal the colour change through a unimanual response. We found that (a) in Experiment 1, the small vs large numerosity of the central cloud of dots did not speed up the detection of left vs right targets, respectively, (b) in Experiment 2, the detection of colour change was not faster in the left side of space when lateral clouds were smaller in numerosity than the central reference and in the right side when clouds were larger in numerosity. These findings show that perceiving non-symbolic numerosity does not cause automatic shifts of spatial attention and suggests no inherent association between the representation of numerosity and that of directional space.

Regional stabilization and H∞ congestion control with input saturation

2021 ◽  
pp. 014233122199273
Author(s):  
Sadek Belamfedel Alaoui ◽  
El Houssaine Tissir ◽  
Noreddine Chaibi ◽  
Fatima El Haoussi
Keyword(s):  
Linear Systems ◽  
Controller Design ◽  
Input Saturation ◽  
Domain Of Attraction ◽  
Queue Management ◽  
Variable Delay ◽  
Challenging Problem ◽  
Regional Stabilization ◽  
Small Gain ◽  
Improved Performance

Designing robust active queue management subjected to network imperfections is a challenging problem. Motivated by this topic, we addressed the problem of controller design for linear systems with variable delay and unsymmetrical constraints by the scaled small gain theorem. We designed two mechanisms: robust enhanced proportional derivative; and robust enhanced proportional derivative subjected to input saturation. Discussion of their practical implementations along with extensive comparisons by MATLAB and NS3 illustrate the improved performance and the enlargement of the domain of attraction regarding some literature results.

Sign in / Sign up

Export Citation Format

Share Document