Dielectrophoretic crossover frequency of individual pearl chains formed by bonded colloidal spheres

Abstract Based upon the Doi-Edwards theory, a simple expression has been obtained for zero-shear viscosity in terms of the plateau modulus and the crossover frequency. There are no adjustable parameters in the expression. The model is in very good agreement with the zero-shear viscosity values for linear polybutadienes, the typical discrepancy being ∼5–10%. If the model can be validated for other linear amorphous polymers, it may become possible to estimate the zero-shear viscosity by measuring a single Theological parameter (the crossover frequency).

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Interplay between Pds5 and Rec8 in regulating chromosome axis length and crossover frequency

Science Advances ◽

10.1126/sciadv.abe7920 ◽

2021 ◽

Vol 7 (11) ◽

pp. eabe7920

Author(s):

Meihui Song ◽

Binyuan Zhai ◽

Xiao Yang ◽

Taicong Tan ◽

Ying Wang ◽

...

Keyword(s):

Recombination Frequency ◽

Crossover Frequency ◽

Wild Type ◽

Protein Levels ◽

Homolog Pairing ◽

Meiotic Chromosomes ◽

Homologous Chromosome Pairing ◽

Axis Length ◽

Chromosome Axis

Meiotic chromosomes have a loop/axis architecture, with axis length determining crossover frequency. Meiosis-specific Pds5 depletion mutants have shorter chromosome axes and lower homologous chromosome pairing and recombination frequency. However, it is poorly understood how Pds5 coordinately regulates these processes. In this study, we show that only ~20% of wild-type level of Pds5 is required for homolog pairing and that higher levels of Pds5 dosage-dependently regulate axis length and crossover frequency. Moderate changes in Pds5 protein levels do not explicitly impair the basic recombination process. Further investigations show that Pds5 does not regulate chromosome axes by altering Rec8 abundance. Conversely, Rec8 regulates chromosome axis length by modulating Pds5. These findings highlight the important role of Pds5 in regulating meiosis and its relationship with Rec8 to regulate chromosome axis length and crossover frequency with implications for evolutionary adaptation.

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Determination of the Rate of Salt-Induced Rapid Coagulation of Polystyrene Latex Particles in Turbulent Flow Using Small Stirred Vessel

Colloids and Interfaces ◽

10.3390/colloids3010005 ◽

2018 ◽

Vol 3 (1) ◽

pp. 5

Author(s):

Oktaviani Oktaviani ◽

Yasuhisa Adachi

Keyword(s):

Ad Hoc ◽

Coupling Effect ◽

Particle Diameter ◽

Polystyrene Latex ◽

Stirred Vessel ◽

Colloidal Spheres ◽

Rapid Coagulation ◽

Mixing Intensity ◽

Mixing Rates ◽

Different Diameters

In our study, we revisited a previously reported method for evaluating the mixing intensity of uniform colloidal spheres in terms of their collision frequency, with the aim of evaluating the validity of this method in the case of a small stirred vessel equipped with an impeller with four paddles. The rates of the salt-induced rapid coagulation of polystyrene latex (PSL) particles with five different diameters were measured as functions of the rotation rate. The ad-hoc assumption of the linear additivity of the perikinetics and the orthokinetics of the coagulation process was used for the analysis. Our previously proposed equation for the rate of turbulent coagulation as a function of the particle diameter, determined for an end-over-end rotation mixing device, was confirmed to be valid. However, it was found that, for small particles and low-mixing rates, i.e., for low Peclet numbers, the rate of coagulation becomes larger than that predicted on the basis of linear additivity because of the coupling effect of Brownian motion and the fluid flow during turbulent mixing. This increase occurred even though the rate was lowered by the wall effect, which resulted in an inhomogeneous distribution of the mixing intensity.

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Transition-Metal Phosphate Colloidal Spheres

Angewandte Chemie International Edition ◽

10.1002/anie.200900639 ◽

2009 ◽

Vol 48 (26) ◽

pp. 4816-4819 ◽

Cited By ~ 60

Author(s):

Chen Chen ◽

Wei Chen ◽

Jun Lu ◽

Deren Chu ◽

Ziyang Huo ◽

...

Keyword(s):

Transition Metal ◽

Metal Phosphate ◽

Colloidal Spheres

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A comparative study on the phase behaviour of highly charged colloidal spheres in a confining wedge geometry

Journal of Physics Condensed Matter ◽

10.1088/0953-8984/17/31/002 ◽

2005 ◽

Vol 17 (31) ◽

pp. S2779-S2786 ◽

Cited By ~ 39

Author(s):

Ana Barreira Fontecha ◽

Hans Joachim Schöpe ◽

Hans König ◽

Thomas Palberg ◽

René Messina ◽

...

Keyword(s):

Comparative Study ◽

Phase Behaviour ◽

Colloidal Spheres

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On Robust Control of Fractional Order Plants: Invariant Phase Margin

Journal of Computational and Nonlinear Dynamics ◽

10.1115/1.4029553 ◽

2015 ◽

Vol 10 (5) ◽

Cited By ~ 5

Author(s):

Mohammad Hossein Basiri ◽

Mohammad Saleh Tavazoei

Keyword(s):

Robust Control ◽

Fractional Order ◽

Phase Margin ◽

Crossover Frequency ◽

Large Uncertainty ◽

Robust Controller ◽

Numerical Examples

Recently, a robust controller has been proposed to be used in control of plants with large uncertainty in location of one of their poles. By using this controller, not only the phase margin and gain crossover frequency are adjustable for the nominal case but also the phase margin remains constant, notwithstanding the variations in location of the uncertain pole of the plant. In this paper, the tuning rule of the aforementioned controller is extended such that it can be applied in control of plants modeled by fractional order models. Numerical examples are provided to show the effectiveness of the tuned controller.

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Rotational dynamics of colloidal spheres probed with fluorescence recovery after photobleaching

The Journal of Chemical Physics ◽

10.1063/1.1644799 ◽

2004 ◽

Vol 120 (9) ◽

pp. 4517-4529 ◽

Cited By ~ 19

Author(s):

M. P. Lettinga ◽

G. H. Koenderink ◽

B. W. M. Kuipers ◽

E. Bessels ◽

A. P. Philipse

Keyword(s):

Fluorescence Recovery After Photobleaching ◽

Rotational Dynamics ◽

Fluorescence Recovery ◽

Colloidal Spheres

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Controlled assembly of single colloidal crystals using electro-osmotic micro-pumps

Physical Chemistry Chemical Physics ◽

10.1039/c6cp07231c ◽

2017 ◽

Vol 19 (4) ◽

pp. 3104-3114 ◽

Cited By ~ 17

Author(s):

Ran Niu ◽

Erdal C. Oğuz ◽

Hannah Müller ◽

Alexander Reinmüller ◽

Denis Botin ◽

...

Keyword(s):

Ion Exchange ◽

Glass Substrate ◽

Colloidal Crystals ◽

Controlled Assembly ◽

Colloidal Spheres

We assemble charged colloidal spheres at deliberately chosen locations on a charged unstructured glass substrate utilizing ion exchange based electro-osmotic micro-pumps.

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