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Biological and Chemical Physics Commons™

Open Access. Powered by Scholars. Published by Universities.®

Statistical, Nonlinear, and Soft Matter Physics

2014

Articles 1 - 7 of 7

Full-Text Articles in Biological and Chemical Physics

Hi-Fidelity Simulation Of The Self-Assembly And Dynamics Of Colloids And Polymeric Solutions With Long Range Interactions, Mahdy Malekzadeh Moghani Dec 2014

Hi-Fidelity Simulation Of The Self-Assembly And Dynamics Of Colloids And Polymeric Solutions With Long Range Interactions, Mahdy Malekzadeh Moghani

Doctoral Dissertations

Modeling the equilibrium properties and dynamic response of the colloidal and polymeric solutions provides valuable insight into numerous biological and industrial processes and facilitates development of novel technologies. To this end, the centerpiece of this research is to incorporate the long range electrostatic or hydrodynamic interactions via computationally efficient algorithms and to investigate the effect of these interactions on the self-assembly of colloidal particles and dynamic properties of polymeric solutions. Specifically, self-assembly of a new class of materials, namely bipolar Janus nano-particles, is investigated via molecular dynamic simulation in order to establish the relationship between individual particle characteristics, such as …

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The Impact Of Membrane Tension On Phase Separation And Solid Domain Properties In Model Multicomponent Vesicles, Dong Chen Nov 2014

The Impact Of Membrane Tension On Phase Separation And Solid Domain Properties In Model Multicomponent Vesicles, Dong Chen

Doctoral Dissertations

Multicomponent phospholipid membranes provide an ideal model to study the complex phase behavior of biological membranes. Giant unilamellar vesicles (GUV) formed by mixtures of two or more phospholipids have particular merit as model membranes because of their simplicity, operability, and ease of viewing phase separation and testing membrane mechanics. Until the research in this thesis, biochemistry and biophysical studies of phase separation in phospholipid membranes primarily addressed the influence of membrane composition on the transition temperatures and domain shapes. This thesis focuses on a commonly neglected variable - membrane tension, analogous to pressure in bulk materials, as an important parameter …

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Heterogeneous Rotational Diffusion Of A Fluorescent Probe In Lipid Monolayers, Christina M. Othon Aug 2014

Heterogeneous Rotational Diffusion Of A Fluorescent Probe In Lipid Monolayers, Christina M. Othon

Christina M Othon

The rotational correlation time of the lipid probe 1-palmitoyl-2-{6-[(7-nitro-2-1,3-benzoxadiazol-4-yl)amino]hexanoyl}-sn-glycero-3-phosphocholine (NBD-PC) is measured using fluorescence anisotropy for two lipid species. We measure the rotational diffusion in a monolayer of 1,2-Didecanoyl-sn-glycero-3-phosphocholine (DPPC) which displays a phase transition at room temperature from the liquid expanded to the liquid-condensed phase. The constant rotational diffusion of the probe throughout the phase transition reflects the measurement of dynamics in only the liquid-expanded phase. We contrast the dynamic changes during this phase coexistence to the continuous density increase observed in 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) at room temperature. We observe a non-exponential decay of the probe diffusion consistent with heterogeneity …

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Searching For Effective Forces In Laboratory Insect Swarms, James G. Puckett, Douglas H. Kelley, Nicholas T. Ouellette Apr 2014

Searching For Effective Forces In Laboratory Insect Swarms, James G. Puckett, Douglas H. Kelley, Nicholas T. Ouellette

Physics and Astronomy Faculty Publications

Collective animal behaviour is often modeled by systems of agents that interact via effective social forces, including short-range repulsion and long-range attraction. We search for evidence of such effective forces by studying laboratory swarms of the flying midge Chironomus riparius. Using multi-camera stereoimaging and particle-tracking techniques, we record three-dimensional trajectories for all the individuals in the swarm. Acceleration measurements show a clear short-range repulsion, which we confirm by considering the spatial statistics of the midges, but no conclusive long-range interactions. Measurements of the mean free path of the insects also suggest that individuals are on average very weakly coupled, but …

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Impact Testing Of Youth-Level Helmets Versus College-Level Helmets, Nicole Hermann Mar 2014

Impact Testing Of Youth-Level Helmets Versus College-Level Helmets, Nicole Hermann

Industrial Technology and Packaging

With so many studies being conducted on professional football players regarding concussions and other related brain injuries, it’s amazing that such an important demographic has been missed. While NFL players are just as subjected to serious injuries as anyone else or even more so, it is important to remember that these players are outfitted, in most cases, with top-of-the-line equipment -- especially their helmets. If the focus is shifted to a younger demographic, youth football players in middle school and high school, the equipment is far less advanced and in a vast majority of cases, has been previously used by …

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A Numerical Assessment Of Cosmic-Ray Energy Diffusion Through Turbulent Media, M. Fatuzzo, F. Melia Jan 2014

A Numerical Assessment Of Cosmic-Ray Energy Diffusion Through Turbulent Media, M. Fatuzzo, F. Melia

Faculty Scholarship

No abstract provided.

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Effects Of Turbulence On Cosmic Ray Propagation In Protostars And Young Stars, M. Fatuzzo, F. C. Adams Jan 2014

Effects Of Turbulence On Cosmic Ray Propagation In Protostars And Young Stars, M. Fatuzzo, F. C. Adams

Faculty Scholarship

No abstract provided.

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