scholarly journals Design and interpretation of cell trajectory assays

2013 ◽  
Vol 10 (88) ◽  
pp. 20130630 ◽  
Author(s):  
Lucie G. Bowden ◽  
Matthew J. Simpson ◽  
Ruth E. Baker
Keyword(s):  
Cell Biology ◽  
Time Interval ◽  
Short Time Interval ◽  
Trajectory Data ◽  
Time Intervals ◽  
Different Types ◽  
Long Time ◽  
A Cell ◽  
Cell Trajectory ◽  
Short Time

Cell trajectory data are often reported in the experimental cell biology literature to distinguish between different types of cell migration. Unfortunately, there is no accepted protocol for designing or interpreting such experiments and this makes it difficult to quantitatively compare different published datasets and to understand how changes in experimental design influence our ability to interpret different experiments. Here, we use an individual-based mathematical model to simulate the key features of a cell trajectory experiment. This shows that our ability to correctly interpret trajectory data is extremely sensitive to the geometry and timing of the experiment, the degree of motility bias and the number of experimental replicates. We show that cell trajectory experiments produce data that are most reliable when the experiment is performed in a quasi-one-dimensional geometry with a large number of identically prepared experiments conducted over a relatively short time-interval rather than a few trajectories recorded over particularly long time-intervals.

Evaluation of time memory in acutely depressed patients, manic patients, and healthy controls using a time reproduction task

2008 ◽  
Vol 23 (6) ◽  
pp. 430-433 ◽  
Author(s):  
Richard Mahlberg ◽  
Thorsten Kienast ◽  
Tom Bschor ◽  
Mazda Adli
Keyword(s):  
Internal Clock ◽  
Time Interval ◽  
Short Time Interval ◽  
Time Intervals ◽  
Reproduction Task ◽  
Time Reproduction ◽  
Depressed Patients ◽  
Long Time ◽  
Short Time ◽  
Manic Patients

AbstractPatients with affective disorders have often been reported to experience subjective changes in how they perceive the flow of time. Time reproduction tasks provide information about the memory component of time perception and are thought to remain unaffected by pulse rate disturbances in the pacemaker of the internal clock.In our study, 30 patients with acute depression, 30 patients with acute mania, and 30 healthy subjects of all age groups were presented with a time reproduction task. Participants were asked to observe a stimulus presented on a computer screen for a certain length of time and, subsequently, to reproduce the stimulus for a similar length of time by pressing the space bar on the computer keyboard. Stimuli were presented to each subject for 1, 6, and 37 s.On average, the time intervals reproduced by manic patients were shorter than those reproduced by depressed patients. Manic patients reproduced the short time interval (6 s) correctly, but under-reproduced the long time interval (37 s, P < 0.001). Depressed patients correctly reproduced the long time interval, but over-reproduced the short time interval (P < 0.001).Remembering time intervals as having been longer than they actually were may lead to a slowed experience of time, as has been described in depressed patients; precisely the converse seems to apply to manic patients.

scholarly journals Optimal Perturbations of an Oceanic Vortex Lens

Fluids ◽  
2018 ◽  
Vol 3 (3) ◽  
pp. 63 ◽  
Author(s):  
Thomas Meunier ◽  
Claire Ménesguen ◽  
Xavier Carton ◽  
Sylvie Le Gentil ◽  
Richard Schopp
Keyword(s):  
Normal Mode ◽  
Growth Rates ◽  
Time Interval ◽  
Time Intervals ◽  
Horizontal Structure ◽  
Azimuthal Wave ◽  
Wave Numbers ◽  
Non Linear ◽  
Long Time ◽  
Short Time

The stability properties of a vortex lens are studied in the quasi geostrophic (QG) framework using the generalized stability theory. Optimal perturbations are obtained using a tangent linear QG model and its adjoint. Their fine-scale spatial structures are studied in details. Growth rates of optimal perturbations are shown to be extremely sensitive to the time interval of optimization: The most unstable perturbations are found for time intervals of about 3 days, while the growth rates continuously decrease towards the most unstable normal mode, which is reached after about 170 days. The horizontal structure of the optimal perturbations consists of an intense counter-shear spiralling. It is also extremely sensitive to time interval: for short time intervals, the optimal perturbations are made of a broad spectrum of high azimuthal wave numbers. As the time interval increases, only low azimuthal wave numbers are found. The vertical structures of optimal perturbations exhibit strong layering associated with high vertical wave numbers whatever the time interval. However, the latter parameter plays an important role in the width of the vertical spectrum of the perturbation: short time interval perturbations have a narrow vertical spectrum while long time interval perturbations show a broad range of vertical scales. Optimal perturbations were set as initial perturbations of the vortex lens in a fully non linear QG model. It appears that for short time intervals, the perturbations decay after an initial transient growth, while for longer time intervals, the optimal perturbation keeps on growing, quickly leading to a non-linear regime or exciting lower azimuthal modes, consistent with normal mode instability. Very long time intervals simply behave like the most unstable normal mode. The possible impact of optimal perturbations on layering is also discussed.

Active Optimum Control of Orthotropic Plates Using Piezoelectric Stiffeners

1993 ◽  
Author(s):  
Victor Birman ◽  
Sarp Adali
Keyword(s):  
Time Interval ◽  
Short Time Interval ◽  
Bending Moments ◽  
Optimum Control ◽  
Orthotropic Plates ◽  
Time Intervals ◽  
Control Forces ◽  
Short Time ◽  
Alternating Voltage ◽  
Over Time

Abstract Active control of orthotropic plates subjected to an impulse loading is considered. The dynamic response is minimized using in-plane forces or bending moments induced by piezoelectric stiffeners bonded to the opposite surfaces of the plate and placed symmetrically with respect to the middle plane. The control forces and moments are activated by a piece-wise constant alternating voltage with varying switch-over time intervals. The magnitude of voltage is bounded while the switch-over time intervals are constantly adjusted to achieve an optimum control. Numerical examples presented in the paper demonstrate the effectiveness of the method and the possibility of reducing the vibrations to very small amplitudes within a short time interval which is in the order of a second.

THE COMPLETE TREATMENT OF THE TIME EVOLUTION IN THE CASE OF A DISCRETIZED ATOM-FIELD INTERACTION MODEL

2001 ◽  
Vol 15 (21) ◽  
pp. 883-894
Author(s):  
J. SEKE ◽  
A. V. SOLDATOV ◽  
N. N. BOGOLUBOV
Keyword(s):  
State Energy ◽  
Interaction Model ◽  
Time Interval ◽  
Short Time Interval ◽  
Field Interaction ◽  
Markovian Dynamics ◽  
Complete Treatment ◽  
Time Regime ◽  
Long Time ◽  
Short Time

The dynamics of a discretized atom-field interaction model with a physically relevant form factor is analyzed. It is shown that after some short time interval only a small fraction of eigenvalues and eigenstates (belonging to the close vicinity of the excited atomic state energy E = ω0/2) contributes to the nondecay probability amplitudes in the long-time regime, whereas the contribution of all other eigenstates and eigenvalues is negligible. Nevertheless, to describe correctly the non-Markovian dynamics in the short-time regime the contribution of all eigenstates and eigenvalues must be taken into account.

scholarly journals Corrosion and Inhibition Effects of Mild Steel in Hydrochloric Acid Solutions Containing Organophosphonic Acid

2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Manish Gupta ◽  
Jyotsna Mishra ◽  
K. S. Pitre
Keyword(s):  
Corrosion Rate ◽  
Mild Steel ◽  
Electrochemical Techniques ◽  
Time Interval ◽  
Time Intervals ◽  
Voltammetric Method ◽  
Average Value ◽  
Long Time ◽  
In The Beginning ◽  
Short Time

A study has been made on the mechanism of corrosion of mild steel and the effect of nitrilo trimethylene phosphonic (NTMP) acid as a corrosion inhibitor in acidic medium, that is, 10% HC1 using the weight loss method and electrochemical techniques, that is, potentiodynamic and galvanostatic polarization measurements. Although corrosion is a long-time process, but it takes place at a faster rate in the beginning which goes on decreasing with due course of time. The above-mentioned methods of corrosion rate determination furnish an average value for a long-time interval. Looking at the versatility and minimum detection limit of the voltammetric method, the authors have developed a new voltammetric method for the determination of corrosion rate at short-time intervals. The results of corrosion of mild steel in 10% HC1 solution with and without NTMP inhibitor at short-time intervals have been reported. The corrosion inhibition efficiency of NTMP is 93% after 24 h.

Statistical mechanism of passenger mobility behaviors for different transportations

2020 ◽  
Vol 31 (06) ◽  
pp. 2050082
Author(s):  
Shaoyong Han ◽  
Qiang Guo ◽  
Kai Yu ◽  
Rende Li ◽  
Bing He ◽  
...  
Keyword(s):  
Large Scale ◽  
Human Mobility ◽  
Probability Model ◽  
Travel Agency ◽  
Time Interval ◽  
Different Types ◽  
Long Time ◽  
Statistical Mechanism ◽  
Short Time ◽  
Interval Distribution

Passengers’ boarding time interval is of great significance for analysis of collective mobility behaviors. In this paper, we empirically investigate the boarding time interval of mobility behaviors based on three large-scale reservation records of passengers traveling by three different types of transportation from a travel agency platform, namely airplane, intercity bus and car rental. The statistical results show that similar properties exist in the passengers’ mobility behaviors, for example, there are similar burstiness [Formula: see text] and memory [Formula: see text] for different time interval distribution, which indicates that the passengers’ mobility behaviors are periodical. Furthermore, we present a probability model to regenerate the empirical results by assuming that the passengers’ next boarding time interval will generate between a short time of 1–7 days with probability [Formula: see text] and a random long time with probability [Formula: see text]. The simulation results show that the presented model can reproduce the burstiness and memory effect of the boarding time interval when [Formula: see text] for three empirical datasets, which suggests the periodical behaviors with the probability [Formula: see text]. This work helps in deeply understanding the regularity of human mobility behaviors.

scholarly journals Accuracy of Broiler Activity Index as Affected by Sampling Time Interval

Animals ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 1102
Author(s):  
Xiao Yang ◽  
Yang Zhao ◽  
George T. Tabler
Keyword(s):  
Activity Index ◽  
Sampling Time ◽  
Time Interval ◽  
Short Time Interval ◽  
Time Intervals ◽  
Commercial Housing ◽  
Computational Resources ◽  
Short Time ◽  
Top View ◽  
Sampling Time Interval

Different time intervals between consecutive images have been used to determine broiler activity index (AI). However, the accuracy of broiler AI as affected by sampling time interval remains to be explored. The objective of this study was to investigate the effect of the sampling time interval (0.04, 0.2, 1, 10, 60, and 300 s) on the accuracy of broiler AI at different bird ages (1–7 weeks), locations (feeder, drinker, and open areas) and times of day (06:00–07:00 h, 12:00–13:00 h, and 18:00–19:00 h). A ceiling-mounted camera was used to capture top-view videos for broiler AI calculations. The results show that the sampling time interval of 0.04 s yielded the highest broiler AI because more bird motion details were captured at this short time interval. The broiler AIs at longer time intervals were 1–99% of that determined at the 0.04-s interval. The broiler AI at 0.2-s interval showed an acceptable accuracy with 80% less computational resources. Broiler AI decreased as birds aged but increased after week 4 at the drinker area. Broiler AI was the highest at the open area for weeks 1–4 and at the feeder and drinker areas for weeks 5–7. It is concluded that the accuracy of broiler AI was significantly affected by sampling time intervals. Broiler AI in commercial housing showed both temporal and spatial variations.

scholarly journals Estimation of Raindrop Size Distribution Parameters Using Lightning Data over West Sumatra

2021 ◽  
Vol 13 (2) ◽  
pp. 92-100
Author(s):  
Faridah Salma ◽  
Marzuki Marzuki ◽  
Hiroyuki Hashiguchi ◽  
Fadli Nauval
Keyword(s):  
Time Interval ◽  
Short Time Interval ◽  
Time Intervals ◽  
Raindrop Size Distribution ◽  
West Sumatra ◽  
Distribution Parameters ◽  
Raindrop Size ◽  
The Tropics ◽  
Short Time

In situ observations of raindrop size distributions (DSDs) are still limited, especially in the tropics. Therefore, this study develops an alternative method to calculate DSD parameters by utilizing lightning data from the World-Wide Lightning Location Network (WWLLN) observation. DSD data was obtained from Parsivel's observations in the equatorial regions of Indonesia, i.e., Kototabang (100.32◦E, 0.20◦S, 865 m above mean sea level/ASL), Padang (100.46°E, 0.915°S, 200 m ASL), and Sicincin (100.30°E, 0.546°S, 134 m ASL). A gamma distribution parameterized the DSD. Three analysis domains were examined, with a grid of 0.1° x 0.1°, 0.5° x 0.5°, and 1° x 1°.  We examined the possibility to calculate the near-instantaneous DSD parameter, so three short time intervals, namely, one, five and ten minutes, were used. The results showed that the number of lightning strokes does not adequately correlate with DSD parameters. This is observed in all time intervals and analysis domains. Thus, the use of lightning data to calculate DSD parameters is not possible for short time interval of DSD (near instantaneous DSD). However, lightning data can estimate the average DSD parameters for an average time of more than one hour, as recommended by previous studies.

Tectonic control on monogenetic volcanism in the Michoacán-Guanajuato Volcanic Field, México

2021 ◽  
Author(s):  
Martha Gabriela Gómez Vasconcelos ◽  
José Luis Macías ◽  
Denis Ramón Avellán ◽  
Giovanni Sosa-Ceballos ◽  
Víctor Hugo Garduño-Monroy
Keyword(s):  
Temporal Distribution ◽  
Tectonic Stress ◽  
Volcanic Field ◽  
Time Interval ◽  
Short Time Interval ◽  
Stress Regime ◽  
Long Time ◽  
Regional Tectonic ◽  
Short Time ◽  
Strombolian Explosions

&lt;p&gt;Aligned volcanism is very common in many monogenetic volcanic fields around the world, which can reveal volcano-tectonic interactions at different scales. For instance, volcanic distribution discloses the tectonic stress orientation on regional scales. On more local scales, preexisting faults or fractures may control magma intrusions and their propagation through the upper crust, as faults are zones of crustal weakness that magma intrusions can intercept during its ascent, partly controlling the volcanic vent spatial distribution. But it is not quite understood how do these alignments occur; if they erupted at the same time (within a few dozens of years), if they erupted during a short time interval (hundreds of years) or during a long time interval (thousands of years); if the eruptive style and magma volumes are controlled by these faults and the regional tectonic stress regime, etc.&lt;/p&gt;&lt;p&gt;This study aims to understand the magmatic and structural conditions that favored the emission of a lava plateau followed by Strombolian explosions that built 13 aligned and six dispersed scoria cones through preexisting E-W&amp;#8211; to ENE-striking faults in the Quer&amp;#233;ndaro area. Our results indicate that volcanism in the Michoac&amp;#225;n-Guanajuato Volcanic Field occurs as intermittent magma fluxes, sometimes represented by independent volcanic vents and sometimes by clustered or aligned volcanoes. Moreover, preexisting faults exert a strong influence on volcanic spatial and temporal distribution, volcanic morphology, magma volume, and eruptive dynamics in this area.&lt;/p&gt;

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