Local dynamic properties

2002 ◽  
Vol 82 (2) ◽  
pp. 133-141 ◽  
Author(s):  
J. L. Feldman ◽  
C. S. Hellberg ◽  
G. Viliani ◽  
W. Garber ◽  
F. M. Tangerman
Keyword(s):  
Dynamic Properties ◽  
Local Dynamic

scholarly journals Simultaneous light and small-angle neutron scattering on aggregating concentrated colloidal suspensions

2003 ◽  
Vol 36 (1) ◽  
pp. 1-6 ◽  
Author(s):  
Sara Romer ◽  
Claus Urban ◽  
Vladimir Lobaskin ◽  
Frank Scheffold ◽  
Anna Stradner ◽  
...  
Keyword(s):  
Neutron Scattering ◽  
Small Angle ◽  
Small Angle Neutron Scattering ◽  
Dynamic Properties ◽  
Sol Gel ◽  
Colloidal Suspensions ◽  
Gel Point ◽  
Local Dynamic ◽  
Colloidal Systems ◽  
High Concentration

A new sample environment has been developed in order to perform light and small-angle neutron scattering (SANS) simultaneously on colloidal systems. The combination of SANS and diffusing wave spectroscopy (DWS) is of particular use in the high-concentration regime. DWS provides information on the local dynamic properties of the individual particles, whereas SANS gives access to the structural properties on similar length scales. The combination of both methods thus allows one to obtain structural and dynamic information over a very large range of length and time scales. Using this new setup, the onset of aggregation and the sol–gel transition in concentrated destabilized polystyrene sphere suspensions have been investigated. At the gel point, a dramatic change of the particle dynamics from diffusion to a subdiffusive arrested motion is observed. However, while the DWS measurements indicate that dramatic changes in the local dynamics occur over a long period, the SANS pattern quickly reaches its final appearance. The SANS experiments thus indicate that a fluid-like structure is arrested in the course of the gel formation. The data are found to be in good qualitative agreement with computer simulations.

Aberrant global and local dynamic properties in schizophrenia with instantaneous phase method based on Hilbert transform

2021 ◽  
pp. 1-11
Author(s):  
Dan Sheng ◽  
Weidan Pu ◽  
Zeqiang Linli ◽  
Guo-Liang Tian ◽  
Shuixia Guo ◽  
...  
Keyword(s):  
Hilbert Transform ◽  
Dynamic Properties ◽  
Temporal Cortex ◽  
Phase Method ◽  
Support Vector ◽  
Local Dynamic ◽  
Dynamic Features ◽  
Instantaneous Phase ◽  
Global Synchrony ◽  
Global And Local

Abstract Background Emerging functional imaging studies suggest that schizophrenia is associated with aberrant spatiotemporal interaction which may result in aberrant global and local dynamic properties. Methods We investigated the dynamic functional connectivity (FC) by using instantaneous phase method based on Hilbert transform to detect abnormal spatiotemporal interaction in schizophrenia. Based on resting-state functional magnetic resonance imaging, two independent datasets were included, with 114 subjects from COBRE [51 schizophrenia patients (SZ) and 63 healthy controls (HCs)] and 96 from OpenfMRI (36 SZ and 60 HCs). Phase differences and instantaneous coupling matrices were firstly calculated at all time points by extracting instantaneous parameters. Global [global synchrony and intertemporal closeness (ITC)] and local dynamic features [strength of FC (sFC) and variability of FC (vFC)] were compared between two groups. Support vector machine (SVM) was used to estimate the ability to discriminate two groups by using all aberrant features. Results We found SZ had lower global synchrony and ITC than HCs on both datasets. Furthermore, SZ had a significant decrease in sFC but an increase in vFC, which were mainly located at prefrontal cortex, anterior cingulate cortex, temporal cortex and visual cortex or temporal cortex and hippocampus, forming significant dynamic subnetworks. SVM analysis revealed a high degree of balanced accuracy (85.75%) on the basis of all aberrant dynamic features. Conclusions SZ has worse overall spatiotemporal stability and extensive FC subnetwork lesions compared to HCs, which to some extent elucidates the pathophysiological mechanism of schizophrenia, providing insight into time-variation properties of patients with other mental illnesses.

Local dynamic properties of the heme pocket in native and solvent-induced molten-globule-like states of cytochrome c

2002 ◽  
Vol 97 (2-3) ◽  
pp. 121-128 ◽  
Author(s):  
V. Militello ◽  
M. Leone ◽  
A. Cupane ◽  
R. Santucci ◽  
A. Desideri
Keyword(s):  
Cytochrome C ◽  
Dynamic Properties ◽  
Molten Globule ◽  
Local Dynamic ◽  
Heme Pocket

Equilibrium and Disequilibrium Dynamics in Cobweb Models with Time Delays

2015 ◽  
Vol 25 (06) ◽  
pp. 1550088 ◽  
Author(s):  
Luca Gori ◽  
Luca Guerrini ◽  
Mauro Sodini
Keyword(s):  
Time Delays ◽  
Chaotic Dynamics ◽  
Dynamic Properties ◽  
Point Of View ◽  
Hopf Bifurcations ◽  
Local Dynamic ◽  
External Shocks ◽  
Global Properties ◽  
Expectations Formation

This paper aims to study price dynamics in two different continuous time cobweb models with delays close to [Hommes, 1994]. In both cases, the stationary equilibrium may be not representative of the long-term dynamics of the model, since it is possible to observe endogenous and persistent fluctuations (supercritical Hopf bifurcations) even if a deterministic context without external shocks is considered. In the model in which markets are in equilibrium every time, we show that the existence of time delays in the expectations formation mechanism may cause chaotic dynamics similar to those obtained in [Hommes, 1994] in a discrete time context. From a mathematical point of view, we apply the Poincaré–Lindstedt perturbation method to study the local dynamic properties of the models. In addition, several numerical experiments are used to investigate global properties of the systems.

scholarly journals Analysis on wetting and local dynamic properties of single water droplet on a polarized solid surface: A molecular dynamics study

2011 ◽  
Vol 135 (1) ◽  
pp. 014703 ◽  
Author(s):  
D. Surblys ◽  
Y. Yamaguchi ◽  
K. Kuroda ◽  
T. Nakajima ◽  
H. Fujimura
Keyword(s):  
Molecular Dynamics ◽  
Solid Surface ◽  
Water Droplet ◽  
Dynamic Properties ◽  
Local Dynamic

A Hybrid Method for Full Spectrum Noise and Vibration Prediction

2003 ◽  
Vol 11 (02) ◽  
pp. 323-338 ◽  
Author(s):  
P. J. Shorter ◽  
B. K. Gardner ◽  
P. G. Bremner
Keyword(s):  
Spatial Statistics ◽  
Dynamic Properties ◽  
Hybrid Approach ◽  
Essential Element ◽  
Experimental Investigations ◽  
Local Dynamic ◽  
Local Motion ◽  
Local Modes ◽  
Numerical Predictions ◽  
Vibration Prediction

Predicting the response of a complex structural-acoustic system across a broad frequency range presents a number of challenges to an analyst. It is quite common to find that the uncertainty associated with the local dynamic properties of various subsystems of a system can vary greatly across the system. It is also common to find that the modal density and wavenumber content of the various subsystems can vary greatly across the system. Typically, this results in a mixture of strongly phase correlated (long wavelength) motion which spans many subsystems, superimposed with weakly phase correlated local motion that is confined to individual subsystems. This mismatch in the local statistical and dynamic properties of a system is often referred to as the mid-frequency problem. This paper provides a qualitative definition of the mid-frequency problem and suggests that a statistical description of the local dynamic properties of a system is an essential element of any mid-frequency prediction method. A hybrid approach to the mid-frequency problem is then described which employs a statistical description of the local modal properties of various subsystems in a system. The spatial statistics of the local modes are of particular interest and the way in which these statistics are encompassed in the hybrid analysis is discussed. Experimental investigations of the spatial statistics of a frame-panel structure are then presented and measurements of the acoustic power radiated by the structure are compared with numerical predictions.

An adaptive routing scheme in scale-free networks

2015 ◽  
Vol 26 (12) ◽  
pp. 1550138 ◽  
Author(s):  
Nora Ben Haddou ◽  
Hamid Ez-Zahraouy ◽  
Abdelilah Benyoussef
Keyword(s):  
Shortest Path ◽  
Routing Protocol ◽  
Dynamic Properties ◽  
Original Model ◽  
Local Dynamic ◽  
Optimal Conditions ◽  
Optimal Form ◽  
Scale Free ◽  
Scale Free Networks ◽  
Traffic Awareness

We suggest an optimal form of traffic awareness already introduced as a routing protocol which combines structural and local dynamic properties of the network to determine the followed path between source and destination of the packet. Instead of using the shortest path, we incorporate the "efficient path" in the protocol and we propose a new parameter α that controls the contribution of the queue in the routing process. Compared to the original model, the capacity of the network can be improved more than twice when using the optimal conditions of our model. Moreover, the adjustment of the proposed parameter allows the minimization of the travel time.

Performance potential of gas foil journal bearings enhanced with micro taper-grooves on top foil

2019 ◽  
Vol 72 (3) ◽  
pp. 299-306
Author(s):  
Ming Feng ◽  
Hongyang Hu ◽  
Tianming Ren
Keyword(s):  
Peer Review ◽  
Dynamic Properties ◽  
Load Capacity ◽  
Dynamic Pressure ◽  
Axial Direction ◽  
Journal Bearings ◽  
Local Dynamic ◽  
The Novel ◽  
Content Type ◽  
Direct Stiffness

Purpose To improve the load capacity and stability of gas foil journal bearings (GFJB), this paper aims to propose a novel GFJB with taper-grooved top foil. Design/methodology/approach A modified bump stiffness model is established considering rounding and friction. By considering the variation of clearance in the circumferential and axial direction, the static and dynamic characteristics of the novel bearing are calculated using the finite difference method, and perturbation method, respectively. The bearing performance under different groove parameters is studied and compared to the traditional bearings. Findings The results show that this novel GFJB can bring multi-extra local dynamic pressure and decrease the gas end leakage, which improves the static and dynamic properties. Moreover, as the increment of groove depth, the load capacity and direct stiffness are reinforced. There is an optimal groove width to maximize the load capacity, and the taper-groove is more beneficial to the improvement of bearing performance than other groove shapes. For the novel GFJB (Ng = 6, Hg = 10µm), the load capacity and direct stiffness increase by about 6.67 and 13.5 per cent, respectively. The stability threshold speed (STS) of a rotor supported by the novel bearings is also increased. Originality/value The performance of the presented novel GFJB is enhanced immensely compared to the traditional bearings, and the results are expected to be helpful to bearing designers, researchers and academicians concerned. Peer review The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2019-0307.

The distribution of antigen on the surface of RBL-2H3 rat basophilic leukemia cells observed by back-scattered electron imaging

1986 ◽  
Vol 44 ◽  
pp. 274-275
Author(s):  
R.F. Stump ◽  
J.R. Pfeiffer ◽  
JC. Seagrave ◽  
D. Huskisson ◽  
J.M. Oliver
Keyword(s):  
Cell Surface ◽  
Dynamic Properties ◽  
Leukemia Cells ◽  
Antigen Binding ◽  
Scattered Electron ◽  
Ige Receptor ◽  
Receptor Complexes ◽  
Rat Basophilic Leukemia Cells ◽  
Electron Imaging ◽  
Basophilic Leukemia

In RBL-2H3 rat basophilic leukemia cells, antigen binding to cell surface IgE-receptor complexes stimulates the release of inflammatory mediators and initiates a series of membrane and cytoskeletal events including a transformation of the cell surface from a microvillous to a lamellar topography. It is likely that dynamic properties of the IgE receptor contribute to the activation of these responses. Fewtrell and Metzger have established that limited crosslinking of IgE-receptor complexes is essential to trigger secretion. In addition, Baird and colleagues have reported that antigen binding causes a rapid immobilization of IgE-receptor complexes, and we have demonstrated an apparent increase with time in the affinity of IgE-receptor complexes for antigen.

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