Compatibility of Popular Three-Dimensional Printed Microfluidics Materials with In Vitro Enzymatic Reactions.

3D printed microfluidics offer several advantages over conventional planar microfabrication techniques including fabrication of 3D microstructures, rapid prototyping, and inertness. While 3D printed materials have been studied for their biocompatibility in cell and tissue culture applications, their compatibility for in vitro biochemistry and molecular biology has not been systematically investigated. Here, we evaluate the compatibility of several common enzymatic reactions in the context of 3D-printed microfluidics: (1) polymerase chain reaction (PCR), (2) T7 in vitro transcription, (3) mammalian in vitro translation, and (4) reverse transcription.

Enabling Flow-Based Kinetic Off-Rate Selections Using a Microfluidic Enrichment Device.

Modern genomic sequencing efforts are identifying potential diagnostic and therapeutic targets more rapidly than existing methods can generate the peptide- and protein-based ligands required to study them. To address this problem, we have developed a microfluidic enrichment device (MFED) enabling kinetic off-rate selection without the use of exogenous competitor. We tuned the conditions of the device (bed volume, flow rate, immobilized target) such that modest, readily achievable changes in flow rates favor formation or dissociation of target-ligand complexes based on affinity.

Accounting for measurement error in log regression models with applications to accelerated testing.

In regression settings, parameter estimates will be biased when the explanatory variables are measured with error. This bias can significantly affect modeling goals. In particular, accelerated lifetime testing involves an extrapolation of the fitted model, and a small amount of bias in parameter estimates may result in a significant increase in the bias of the extrapolated predictions.

RasIns: Genetically Encoded Intrabodies of Activated Ras Proteins.

K- and H-Ras are the most commonly mutated genes in human tumors and are critical for conferring and maintaining the oncogenic phenotype in tumors with poor prognoses. Here, we design genetically encoded antibody-like ligands (intrabodies) that recognize active, GTP-bound K- and H-Ras. These ligands, which use the 10th domain of human fibronectin as their scaffold, are stable inside the cells and when fused with a fluorescent protein label, the constitutively active G12V mutant H-Ras.

1H and 13C NMR assignments for the cyanine dyes SYBR Safe and thiazole orange.

Analysis of (1)H and (13)C NMR and mass spectral data for the fluorescent nucleic acid stain SYBR Safe indicates that it contains a cyanine-based cationic core structure identical to thiazole orange. The difference between these two compounds is the type of N-substitution on the quinolinium ring system (SYBR Safe, n-Pr; thiazole orange, Me). The (1)H and (13)C NMR resonances for both compounds were assigned on the basis of one- and two-dimensional (COSY, ROESY, HSQC, and HMBC) experiments.

Synthesis and characterization of photoluminescent In-doped CdSe nanoparticles.

Indium-doped CdSe nanoparticles have been synthesized and characterized. Their light absorption, photoluminescence, and structure are similar to undoped CdSe nanoparticles. The greater part of the In associated with the nanoparticles is removed when the nanoparticles undergo ligand exchange by pyridine.

Generalized emissivity inverse problem.

Inverse problems have recently drawn considerable attention from the physics community due to of potential widespread applications [K. Chadan and P. C.

Functional integral approach: a third formulation of quantum statistical mechanics.

Quantum statistical mechanics has developed primarily through two approaches, pioneered by Gibbs and Feynman, respectively. In Gibbs' method one calculates partition functions from phase-space integrations or sums over stationary states. Alternatively, in Feynman's approach, the focus is on the path-integral formulation.