Particle sizes of purified κ-casein: Metal effect and correspondence with predicted three-dimensional molecular models

Abstract. We study the problem of sinking particles in a realistic oceanic flow, with major energetic structures in the mesoscale, focussing on the range of particle sizes and densities appropriate for marine biogenic particles. Our aim is to evaluate the relevance of theoretical results of finite size particle dynamics in their applications in the oceanographic context. By using a simplified equation of motion of small particles in a mesoscale simulation of the oceanic velocity field, we estimate the influence of physical processes such as the Coriolis force and the inertia of the particles, and we conclude that they represent negligible corrections to the most important terms, which are passive motion with the velocity of the flow, and a constant added vertical velocity due to gravity. Even if within this approximation three-dimensional clustering of particles can not occur, two-dimensional cuts or projections of the evolving three-dimensional density can display inhomogeneities similar to the ones observed in sinking ocean particles.

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Prediction of B-Cell Epitopes in Listeriolysin O, a Cholesterol Dependent Cytolysin Secreted by Listeria monocytogenes

Advances in Bioinformatics ◽

10.1155/2014/871676 ◽

2014 ◽

Vol 2014 ◽

pp. 1-9 ◽

Cited By ~ 2

Author(s):

Morris S. Jones ◽

J. Mark Carter

Keyword(s):

Monoclonal Antibodies ◽

Listeria Monocytogenes ◽

B Cell ◽

Three Dimensional ◽

Listeriolysin O ◽

Molecular Models ◽

B Cell Epitopes ◽

Discontinuous Epitopes ◽

Pathogenic Effects ◽

Domain 4

Listeria monocytogenes is a gram-positive, foodborne bacterium responsible for disease in humans and animals. Listeriolysin O (LLO) is a required virulence factor for the pathogenic effects of L. monocytogenes. Bioinformatics revealed conserved putative epitopes of LLO that could be used to develop monoclonal antibodies against LLO. Continuous and discontinuous epitopes were located by using four different B-cell prediction algorithms. Three-dimensional molecular models were generated to more precisely characterize the predicted antigenicity of LLO. Domain 4 was predicted to contain five of eleven continuous epitopes. A large portion of domain 4 was also predicted to comprise discontinuous immunogenic epitopes. Domain 4 of LLO may serve as an immunogen for eliciting monoclonal antibodies that can be used to study the pathogenesis of L. monocytogenes as well as develop an inexpensive assay.

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Cryoelectron Tomography

Microscopy Today ◽

10.1017/s1551929500052597 ◽

2003 ◽

Vol 11 (3) ◽

pp. 3-4

Author(s):

Stephen W. Carmichael

Keyword(s):

Electron Micrographs ◽

Molecular Level ◽

Three Dimensional ◽

Two Dimensions ◽

Cellular Structures ◽

Molecular Models ◽

3D Images

We have all seen beautiful three-dimensional (3D) renderings of molecular models, complete with helices and pleated sheets. And for more than half a century we have also seen electron micrographs of cellular structures, although usually in two dimensions. There has been a gap between these two sets of images. By developing a technique that promises 3D images at resolutions approaching the molecular level, Ohad Medalia, Igor Weber, Achilleas Frangakis, Daniela Nicastro Günther Gerisch, and Wolfgang Baumeister have bridged that gap.

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The Effect of Microstructural Morphologies on the Effective Electromechanical Properties of Piezoelectric Particle Composites

Volume 8: Mechanics of Solids, Structures and Fluids ◽

10.1115/imece2012-88915 ◽

2012 ◽

Author(s):

Vahid Tajeddini ◽

Chien-hong Lin ◽

Anastasia Muliana ◽

Martin Lévesque

Keyword(s):

Mechanical Properties ◽

Elastic Moduli ◽

Volume Fraction ◽

Micromechanical Model ◽

Three Dimensional ◽

Particle Sizes ◽

Reinforced Composites ◽

Electromechanical Properties ◽

Particle Volume ◽

Self Consistent

This study introduces a micromechanical model that incorporates detailed microstructures for analyzing the effective electro-mechanical properties, such as piezoelectric and permittivity constants as well as elastic moduli, of piezoelectric particle reinforced composites. The studied composites consist of polarized spherical piezoelectric particles dispersed into a continuous and elastic polymeric matrix. A micromechanical model generated using three-dimensional (3D) continuum elements within a finite element (FE) framework. For each volume fraction (VF) of particles, realization with different particle sizes and arrangements were generated in order to represent microstructures of a particle composite. We examined the effects of microstructural morphologies, such as particle sizes and distributions, and particle volume fractions on the overall effective electro-mechanical properties of the active composites. The overall electro-mechanical properties determined from the present micromechanical model were compared to those generated using the Mori-Tanaka, self-consistent, and simplified unit-cell micromechanical models.

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Environmental influences on the particle sizes of purified κ-casein: metal effect

International Dairy Journal ◽

10.1016/s0958-6946(99)00060-6 ◽

1999 ◽

Vol 9 (3-6) ◽

pp. 193-199 ◽

Cited By ~ 6

Author(s):

Harold M. Farrell ◽

Thomas F. Kumosinski ◽

Peter H. Cooke ◽

Peter D. Hoagland ◽

Edward D. Wickham ◽

...

Keyword(s):

Environmental Influences ◽

Particle Sizes ◽

Metal Effect

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Engineering 3D Printed Microfluidic Chips for the Fabrication of Nanomedicines

Pharmaceutics ◽

10.3390/pharmaceutics13122134 ◽

2021 ◽

Vol 13 (12) ◽

pp. 2134

Author(s):

Aytug Kara ◽

Athina Vassiliadou ◽

Baris Ongoren ◽

William Keeble ◽

Richard Hing ◽

...

Keyword(s):

3D Printing ◽

Polymeric Nanoparticles ◽

Scale Up ◽

Unmet Need ◽

Three Dimensional ◽

Cost Effective ◽

Particle Sizes ◽

Microfluidic Chips ◽

Acid Media ◽

3D Printed

Currently, there is an unmet need to manufacture nanomedicines in a continuous and controlled manner. Three-dimensional (3D) printed microfluidic chips are an alternative to conventional PDMS chips as they can be easily designed and manufactured to allow for customized designs that are able to reproducibly manufacture nanomedicines at an affordable cost. The manufacturing of microfluidic chips using existing 3D printing technologies remains very challenging because of the intricate geometry of the channels. Here, we demonstrate the manufacture and characterization of nifedipine (NFD) polymeric nanoparticles based on Eudragit L-100 using 3D printed microfluidic chips with 1 mm diameter channels produced with two 3D printing techniques that are widely available, stereolithography (SLA) and fuse deposition modeling (FDM). Fabricated polymeric nanoparticles showed good encapsulation efficiencies and particle sizes in the range of 50–100 nm. SLA chips possessed better channel resolution and smoother channel surfaces, leading to smaller particle sizes similar to those obtained by conventional manufacturing methods based on solvent evaporation, while SLA manufactured nanoparticles showed a minimal burst effect in acid media compared to nanoparticles fabricated with FDM chips. Three-dimensional printed microfluidic chips are a novel and easily amenable cost-effective strategy to allow for customization of the design process for continuous manufacture of nanomedicines under controlled conditions, enabling easy scale-up and reducing nanomedicine development times, while maintaining high-quality standards.

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Implementing a modeling software for animated protein-complex interactions using a physics simulation library

Journal of Bioinformatics and Computational Biology ◽

10.1142/s0219720014420037 ◽

2014 ◽

Vol 12 (06) ◽

pp. 1442003 ◽

Cited By ~ 1

Author(s):

Yutaka Ueno ◽

Shuntaro Ito ◽

Akihiko Konagaya

Keyword(s):

Three Dimensional ◽

Rigid Body Dynamics ◽

Dynamics Simulation ◽

Molecular Models ◽

Body Dynamics ◽

Physics Simulation ◽

Modeling Software ◽

Physical Simulations ◽

A Cell ◽

Scripting Language

To better understand the behaviors and structural dynamics of proteins within a cell, novel software tools are being developed that can create molecular animations based on the findings of structural biology. This study proposes our method developed based on our prototypes to detect collisions and examine the soft-body dynamics of molecular models. The code was implemented with a software development toolkit for rigid-body dynamics simulation and a three-dimensional graphics library. The essential functions of the target software system included the basic molecular modeling environment, collision detection in the molecular models, and physical simulations of the movement of the model. Taking advantage of recent software technologies such as physics simulation modules and interpreted scripting language, the functions required for accurate and meaningful molecular animation were implemented efficiently.

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