Brief of Amici Curiae in Support of Appellant, James Townsend v. Midland Funding, LLC

The Consumer Protection Clinic of the University of Maryland Francis King Carey School of Law, filed a Motion to Participate and an Amicus Brief in the case of Townsend v. Midland Funding, LLC. The case presents the question of whether documents created by third party predecessors in interest—usually a bank—may be admitted into evidence when a debt buyer plaintiff does not demonstrate personal knowledge regarding any of the foundational elements which would be required to admit the documents under the business records exception to the hearsay rule. Amici urge the Court to overturn the lower court, and hold that a debt buyer’s documents may not be admitted into evidence without the debt buyer first laying the proper foundation for the business records exception to the hearsay rule. The Clinic was joined by AARP, the National Consumer Law Center, the National Association of Consumer Advocates, and by the Maryland Legal Aid Bureau and Maryland\u27s Public Justice Center. The Brief deals with the problems of data integrity and the lack of competent, reliable evidence in lawsuits filed purchasers of charged off credit card debt, known as debt buyers. The Consumer Protection Clinic and other amici examine due process and professionalism concerns which arise when our courts (primarily Maryland\u27s District Court) do not strictly apply the special evidentiary and procedural rules which exist for small claims actions

Pushing the glass transition towards random close packing using self-propelled hard spheres

Although the concept of random close packing with an almost universal packing fraction of ~ 0.64 for hard spheres was introduced more than half a century ago, there are still ongoing debates. The main difficulty in searching the densest packing is that states with packing fractions beyond the glass transition at ~ 0.58 are inherently non-equilibrium systems, where the dynamics slows down with a structural relaxation time diverging with density; hence, the random close packing is inaccessible. Here we perform simulations of self-propelled hard spheres, and we find that with increasing activity the relaxation dynamics can be sped up by orders of magnitude. The glass transition shifts to higher packing fractions upon increasing the activity, allowing the study of sphere packings with fluid-like dynamics at packing fractions close to random close packing. Our study opens new possibilities of investigating dense packings and the glass transition in systems of hard particles

Self-consistent field predictions for quenched spherical biocompatible triblock copolymer micelles

We have used the Scheutjens-Fleer self-consistent field (SF-SCF) method to predict the self-assembly of triblock copolymers with a solvophilic middle block and sufficiently long solvophobic outer blocks. We model copolymers consisting of polyethylene oxide (PEO) as solvophilic block and poly(lactic-co-glycolic) acid (PLGA) or poly({\ko}-caprolactone) (PCL) as solvophobic block. These copolymers form structurally quenched spherical micelles provided the solvophilic block is long enough. Predictions are calibrated on experimental data for micelles composed of PCL-PEO-PCL and PLGA-PEO-PLGA triblock copolymers prepared via the nanoprecipitation method. We establish effective interaction parameters that enable us to predict various micelle properties such as the hydrodynamic size, the aggregation number and the loading capacity of the micelles for hydrophobic species that are consistent with experimental finding.Comment: accepted for publication in Soft Matte

Controlled Nanoparticle Formation by Diffusion Limited Coalescence

Polymeric nanoparticles (NPs) have a great application potential in science and technology. Their functionality strongly depends on their size. We present a theory for the size of NPs formed by precipitation of polymers into a bad solvent in the presence of a stabilizing surfactant. The analytical theory is based upon diffusion-limited coalescence kinetics of the polymers. Two relevant time scales, a mixing and a coalescence time, are identified and their ratio is shown to determine the final NP diameter. The size is found to scale in a universal manner and is predominantly sensitive to the mixing time and the polymer concentration if the surfactant concentration is sufficiently high. The model predictions are in good agreement with experimental data. Hence the theory provides a solid framework for tailoring nanoparticles with a priori determined size.Comment: 4 pages, 3 figure

Trigger sequence can influence final morphology in the self-assembly of asymmetric telechelic polymers

We report on a numerical study of polymer network formation of asymmetric biomimetic telechelic polymers with two reactive ends based on a self-assembling collagen, elastin or silk-like polypeptide sequence. The two reactive ends of the polymer can be activated independently using physicochemical triggers such as temperature and pH. We show, using a simple coarse grained model that the order in which this triggering occurs influences the final morphology. For both of collagen-silk and elastin-silk topologies we find that for relatively short connector chains the morphology of the assembly is greatly influenced by the order of the trigger, whereas for longer chains the equilibrium situation is more easily achieved. Moreover, self-assembly is greatly enhanced at moderate collagen interaction strength, due to facilitated binding and unbinding of the peptides. This finding indicates that both the trigger sequence and strength can be used to steer self-assembly in these biomimetic polymer systems.</p

Sparse Deterministic Approximation of Bayesian Inverse Problems

We present a parametric deterministic formulation of Bayesian inverse problems with input parameter from infinite dimensional, separable Banach spaces. In this formulation, the forward problems are parametric, deterministic elliptic partial differential equations, and the inverse problem is to determine the unknown, parametric deterministic coefficients from noisy observations comprising linear functionals of the solution. We prove a generalized polynomial chaos representation of the posterior density with respect to the prior measure, given noisy observational data. We analyze the sparsity of the posterior density in terms of the summability of the input data's coefficient sequence. To this end, we estimate the fluctuations in the prior. We exhibit sufficient conditions on the prior model in order for approximations of the posterior density to converge at a given algebraic rate, in terms of the number $N$ of unknowns appearing in the parameteric representation of the prior measure. Similar sparsity and approximation results are also exhibited for the solution and covariance of the elliptic partial differential equation under the posterior. These results then form the basis for efficient uncertainty quantification, in the presence of data with noise

Charge inversion and colloidal stability of carbon black in battery electrolyte solutions

Colloids and Surfaces A: Physicochemical and Engineering Aspects is an international journal devoted to the science of the fundamentals, engineering fundamentals, and applications of colloidal and interfacial phenomena and processes. The journal aims at publishing research papers of high quality and lasting value. In addition, the journal contains critical review papers by acclaimed experts, brief notes, letters, book reviews, and announcements. Basic areas of interest include the following: theory and experiments on fluid interfaces; adsorption; surface aspects of catalysis; dispersion preparation, characterization and stability; aerosols, foams and emulsions; surfaces forces; micelles and microemulsions; light scattering and spectroscopy; detergency and wetting; thin films, liquid membranes and bilayers; surfactant science; polymer colloids; rheology of colloidal and disperse systems; electrical phenomena in interfacial and disperse systems. These and related areas are rich and broadly applicable to many industrial, biological and agricultural systems. Of interest are applications of colloidal and interfacial phenomena in the following areas: separation processes; materials processing; biological systems (see also companion publication Colloids and Surfaces B: Biointerfaces); environmental and aquatic systems; minerals extraction and metallurgy; paper and pulp production; coal cleaning and processing; oil recovery; household products and cosmetics; pharmaceutical preparations; agricultural, soil and food engineering; chemical and mechanical engineering