scholarly journals A bending fluctuation-based mechanism for particle detection by ciliated structures

2021 ◽  
Vol 118 (31) ◽  
pp. e2020402118
Author(s):  
Jean-Baptiste Thomazo ◽  
Benjamin Le Révérend ◽  
Lea-Laetitia Pontani ◽  
Alexis M. Prevost ◽  
Elie Wandersman
Keyword(s):  
Single Particle ◽  
Mechanical Response ◽  
Complex Fluids ◽  
Elastic Fiber ◽  
Continuous Phase ◽  
Phase Flow ◽  
Particle Detection ◽  
Suspension Concentration ◽  
Statistical Framework ◽  
Fiber Interaction

To mimic the mechanical response of passive biological cilia in complex fluids, we study the bending dynamics of an anchored elastic fiber submitted to a dilute granular suspension under shear. We show that the bending fluctuations of the fiber accurately encode minute variations of the granular suspension concentration. Indeed, besides the stationary bending induced by the continuous phase flow, the passage of each single particle induces an additional deflection. We demonstrate that the dominant particle/fiber interaction arises from contacts of the particles with the fiber, and we propose a simple elastohydrodynamics model to predict their amplitude. Our results provide a mechanistic and statistical framework to describe particle detection by biological ciliated systems.

scholarly journals Prediction Models of Droplet Characteristics Based on the Locally Convergent Configurations in PMMA Microchips

2021 ◽  
Vol 2097 (1) ◽  
pp. 012027
Author(s):  
Zhongxin Liu ◽  
Zhiliang Wang ◽  
Chao Wang ◽  
Jinsong Zhang
Keyword(s):  
Flow Rate ◽  
Relative Position ◽  
Prediction Models ◽  
Continuous Phase ◽  
Lubricating Oil ◽  
Flow Rate Ratio ◽  
Phase Flow ◽  
Exponential Relationship ◽  
Two Phase ◽  
Relationship Of

Abstract This paper novel designed the local convergence configuration in the coaxial channels to study the two-phase flow (lubricating oil (continuous phase, flow rate Q c)/deionized water (dispersed phase, flow rate Q d)). Two geometric control variables, the relative position (x) and tapering characteristics (α), had the different effects on the droplet formation. The increase of relative position x caused the higher frequency and finer droplets, and the increase of convergence angle α, took the opposite effects. The results indicated that the equivalent dimensionless droplet length Ld/Wout and the flow rate ratio Qd/Qc had an exponential relationship of about 1/2. Similarly, it was found that the dispersed droplets generating frequency and the two-phase capillary number, CaTP = uTPμc/σ, had an exponential relationship. The advantage of the convergent configurations in micro-channel was the size and efficiency of droplet generation was very favorable to be controlled by α and x.

Optical single-particle detection in nanoholes towards simple parallel detection of molecular binding events

2012 ◽  
Vol 93 (2) ◽  
pp. 140-151 ◽  
Author(s):  
Norbert Jahr ◽  
Nicole Hädrich ◽  
Mamuna Anwar ◽  
Andrea Csaki ◽  
Ondra Stranik ◽  
...  
Keyword(s):  
Single Particle ◽  
Particle Detection ◽  
Molecular Binding ◽  
Parallel Detection ◽  
Single Particle Detection

scholarly journals Automated single particle detection and tracking for large microscopy datasets

2016 ◽  
Vol 3 (5) ◽  
pp. 160225 ◽  
Author(s):  
Rhodri S. Wilson ◽  
Lei Yang ◽  
Alison Dun ◽  
Annya M. Smyth ◽  
Rory R. Duncan ◽  
...  
Keyword(s):  
Single Molecule ◽  
Single Particle ◽  
Image Data ◽  
Ground Truth ◽  
Detection Algorithm ◽  
Large Datasets ◽  
Single Particle Tracking ◽  
Synthetic Image ◽  
Particle Detection ◽  
Very Large Datasets

Recent advances in optical microscopy have enabled the acquisition of very large datasets from living cells with unprecedented spatial and temporal resolutions. Our ability to process these datasets now plays an essential role in order to understand many biological processes. In this paper, we present an automated particle detection algorithm capable of operating in low signal-to-noise fluorescence microscopy environments and handling large datasets. When combined with our particle linking framework, it can provide hitherto intractable quantitative measurements describing the dynamics of large cohorts of cellular components from organelles to single molecules. We begin with validating the performance of our method on synthetic image data, and then extend the validation to include experiment images with ground truth. Finally, we apply the algorithm to two single-particle-tracking photo-activated localization microscopy biological datasets, acquired from living primary cells with very high temporal rates. Our analysis of the dynamics of very large cohorts of 10 000 s of membrane-associated protein molecules show that they behave as if caged in nanodomains. We show that the robustness and efficiency of our method provides a tool for the examination of single-molecule behaviour with unprecedented spatial detail and high acquisition rates.

scholarly journals Development, Characterization, and Application of a Versatile Single Particle Detection Apparatus for Time-Integrated and Time-Resolved Fluorescence Measurements—Part II: Experimental Evaluation

2009 ◽  
Vol 2009 ◽  
pp. 1-14
Author(s):  
Xihong Wu ◽  
J. A. Merten ◽  
N. Omenetto ◽  
B. W. Smith ◽  
J. D. Winefordner
Keyword(s):  
Single Particle ◽  
Narrow Beam ◽  
Time Resolved Fluorescence ◽  
Particle Detection ◽  
Time Resolved ◽  
Endogenous Fluorophores ◽  
Fluorescence Measurements ◽  
On Line ◽  
Single Particle Detection ◽  
Speed Mode

This paper describes the experimental realization and characterization of a versatile single particle detection apparatus. The system utilizes a novel particle beam inlet that can serve as either an on-line particle concentrator (i.e., all diameters confined in a narrow beam) or as a segregator (i.e., selected diameters confined in a narrow beam) and can be operated in a high-speed mode as well as in a low-speed mode, thus allowing different interaction times between the particles and the laser beam. An aerodynamic sizing technique has been incorporated into the system to provide rapid, real-time, and high-resolution sizing. Parameters such as transmission efficiency and size-segregation efficiency have been measured. The performance of the instrument has been demonstrated by on-line detection of spectrally resolved and time resolved fluorescence detection from airborne dye-doped particles and aerosolized endogenous fluorophores found in biological agents.

scholarly journals Modelling of Evanescent Field Scattering

Proceedings ◽  
2020 ◽  
Vol 56 (1) ◽  
pp. 16
Author(s):  
Andreas Tortschanoff ◽  
Marcus Baumgart ◽  
Jaka Pribošek
Keyword(s):  
Numerical Analysis ◽  
Single Particle ◽  
Evanescent Field ◽  
Promising Method ◽  
Analytical Models ◽  
Particle Scattering ◽  
Particle Detection ◽  
Sensing Mechanism ◽  
Single Particle Detection

Evanescent field particle scattering is a promising method for single particle detection. In this study, we performed a detailed numerical analysis to show the possibilities and limitations of analytical models for predicting the capabilities of this sensing mechanism.

scholarly journals Elastic Fibers and Large Artery Mechanics in Animal Models of Development and Disease

2018 ◽  
Vol 140 (2) ◽  
Author(s):  
Maria Gabriela Espinosa ◽  
Marius Catalin Staiculescu ◽  
Jungsil Kim ◽  
Eric Marin ◽  
Jessica E. Wagenseil
Keyword(s):  
Animal Models ◽  
Mechanical Behavior ◽  
Computational Models ◽  
Mechanical Response ◽  
Elastic Fiber ◽  
High Stress ◽  
Elastic Fibers ◽  
Large Artery ◽  
Fiber Network ◽  
Pulsatile Pressure

Development of a closed circulatory system requires that large arteries adapt to the mechanical demands of high, pulsatile pressure. Elastin and collagen uniquely address these design criteria in the low and high stress regimes, resulting in a nonlinear mechanical response. Elastin is the core component of elastic fibers, which provide the artery wall with energy storage and recoil. The integrity of the elastic fiber network is affected by component insufficiency or disorganization, leading to an array of vascular pathologies and compromised mechanical behavior. In this review, we discuss how elastic fibers are formed and how they adapt in development and disease. We discuss elastic fiber contributions to arterial mechanical behavior and remodeling. We primarily present data from mouse models with elastic fiber deficiencies, but suggest that alternate small animal models may have unique experimental advantages and the potential to provide new insights. Advanced ultrastructural and biomechanical data are constantly being used to update computational models of arterial mechanics. We discuss the progression from early phenomenological models to microstructurally motivated strain energy functions for both collagen and elastic fiber networks. Although many current models individually account for arterial adaptation, complex geometries, and fluid–solid interactions (FSIs), future models will need to include an even greater number of factors and interactions in the complex system. Among these factors, we identify the need to revisit the role of time dependence and axial growth and remodeling in large artery mechanics, especially in cardiovascular diseases that affect the mechanical integrity of the elastic fibers.

Analysis of Oil-Water-Gas Three-Phase Flow in a Curved Leaking Pipe

2016 ◽  
Vol 366 ◽  
pp. 144-150
Author(s):  
Boniek Evangelista Leite ◽  
Severino Rodrigues de Farias Neto ◽  
Antonio Gilson Barbosa de Lima ◽  
Lígia Rafaely Barbosa Sarmento
Keyword(s):  
Continuous Phase ◽  
Environmental Damage ◽  
Particle Model ◽  
Phase Flow ◽  
Curved Pipe ◽  
Three Phase ◽  
Three Phase Flow ◽  
Oil Water ◽  
Object Of Study ◽  
Water Gas

The onshore and offshore production of oil and natural gas is characterized by the multiphase flow in ducts and pipes, which are interconnected by various equipments such as wellhead, pumps, compressors, processing platforms, among others. The transport of oil and oil products is essential to the viability of the sector, but is susceptible to failures, that can cause great environmental damage. Considering this necessity of the transportation sector of oil and derivatives, leakage in pipelines with curved connections, are the object of study for various researchers. In this sense, this work contributes to the study of three-phase flow (oil-water-gas) in a curved pipe (90°) using Computational Fluid Dynamics. The physical domain is constituted by two tubes of 4 meters trenched by a 90° curve, with the poring whole in the curvated accessory. The mathematical model is based on a particle model, where the oil is considered as a continuous phase and the water and gas as a particulate phase. The SST (Shear Stress Transport) turbulence model was adopted. All simulations were carried out using the Ansys CFX® 12.1 commercial code. Results of the pressure, velocity and volumetric fraction of the phases are presented and discussed.

A Structurally Based Stress-Stretch Relationship for Tendon and Ligament

1997 ◽  
Vol 119 (4) ◽  
pp. 392-399 ◽  
Author(s):  
C. Hurschler ◽  
B. Loitz-Ramage ◽  
R. Vanderby
Keyword(s):  
Distribution Function ◽  
Probability Distribution ◽  
Failure Criterion ◽  
Probability Distribution Function ◽  
Mechanical Response ◽  
Elastic Fiber ◽  
Tissue Level ◽  
Constitutive Law ◽  
Failure Behavior ◽  
Simplified Form

We propose a mechanical model for tendon or ligament stress–stretch behavior that includes both microstructural and tissue level aspects of the structural hierarchy in its formulation. At the microstructural scale, a constitutive law for collagen fibers is derived based on a strain-energy formulation. The three-dimensional orientation and deformation of the collagen fibrils that aggregate to form fibers are taken into consideration. Fibril orientation is represented by a probability distribution function that is axisymmetric with respect to the fiber. Fiber deformation is assumed to be incompressible and axisymmetric. The matrix is assumed to contribute to stress only through a constant hydrostatic pressure term. At the tissue level, an average stress versus stretch relation is computed by assuming a statistical distribution for fiber straightening during tissue loading. Fiber straightening stretch is assumed to be distributed according to a Weibull probability distribution function. The resulting comprehensive stress–stretch law includes seven parameters, which represent structural and microstructural organization, fibril elasticity, as well as a failure criterion. The failure criterion is stretch based. It is applied at the fibril level for disorganized tissues but can be applied more simply at a fiber level for well-organized tissues with effectively parallel fibrils. The influence of these seven parameters on tissue stress–stretch response is discussed and a simplified form of the model is shown to characterize the nonlinear experimentally determined response of healing medial collateral ligaments. In addition, microstructural fibril organizational data (Frank et al., 1991, 1992) are used to demonstrate how fibril organization affects material stiffness according to the formulation. A simplified form, assuming a linearly elastic fiber stress versus stretch relationship, is shown to be useful for quantifying experimentally determined nonlinear toe-in and failure behavior of tendons and ligaments. We believe this ligament and tendon stress–stretch law can be useful in the elucidation of the complex relationships between collagen structure, fibril elasticity, and mechanical response.

Sign in / Sign up

Export Citation Format

Share Document