10,000 publications from this institution
A method of selective detection of a concentration of a metal ion species in a subject is provided in which a biofluid sample is obtained from the subject. The biofluid sample is exposed to a functionalized porous aromatic polymer. The polymer selectively captures and concentrates the metal ion species from the biofluid. Subsequently, the biofluid is washed from the polymer. The polymer is then exposed to a solution comprising a colorimetric indicator that extracts the metal ion species from the washed polymer thereby changing a color of the solution as a function of an amount of the metal ion species in the polymer. The concentration of the metal ion species in the subject is then spectroscopically determined from the color of the solution.
No abstract is provided for this article.
The rates at which energy and particle densities move to equalize arbitrarily large temperature and chemical potential differences in an isolated quantum system have an emergent thermodynamical description whenever the energy or particle current commutes with the Hamiltonian. Concrete examples include the energy current in the 1D spinless fermion model with nearest-neighbor interactions (XXZ spin chain), the energy current in Lorentz-invariant theories or the particle current in interacting Bose gases in arbitrary dimension. Even far from equilibrium, these rates are controlled by state functions, which we call “expansion potentials,” expressed as integrals of equilibrium Drude weights. This relation between nonequilibrium quantities and linear response implies nonequilibrium Maxwell relations for the Drude weights. We verify our results via density-matrix renormalization group calculations for the XXZ chain.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
-
Experimentally determined growth laws of bilayer tantalum oxide films formed by anodizing sputter-deposited tantalum anodes in a 0.1 M phosphoric acid electrolyte are reported. Transmission electron microscopy, Fourier transform IR reflectance spectroscopy, and wet capacitance measurements are used to measure the growth rates of the inner layer, the outer layer, and the total bilayer oxide thickness in the time domain of . The anodization constants for 250 mV/s potentiodynamic growth in 0.1 M followed by a 50 min hold at the formation voltage are , , and for the total oxide, the inner layer, and the outer layer, respectively. After several days of anodization, the oxide continues to grow, thus confirming the lack of significant tantalum oxide dissolution in nonfluorinated electrolytes. Parametrization of the growth laws allows the ionic currents that are due to the generation of oxygen vacancies and tantalum interstitials to be separately calculated.
The synthesis of medium-sized rings is a formidable challenge in organic chemistry. Toward this end transition-metal-catalyzed intramolecular cyclopropanation via carbenoids has been applied. The authors report a gold(I)-catalyzed process for the asymmetric synthesis of seven- and eight-membered rings. The present work represents an advancement over existing methods of transition-metal-catalyzed intramolecular cyclopropanation and extends the authors previous work involving the transformations of gold(I) carbenoids.
Patients with insomnia commonly complain that they are unable to get to sleep because of unwanted thoughts and worries. One account given of this excess cognitive activity is that it results from the incomplete processing of daytime stressors and hassles. Previous research has demonstrated the benefits of writing about emotional experiences as a method to facilitate emotional processing. This pilot study tested the hypothesis that writing about worries and concerns, with an emphasis on the expression and processing of emotion, will reduce sleep onset latency among an analogue sample of poor sleepers. Forty-two poor sleepers were randomly allocated to 1 of 3 groups for 3 nights; the instructions for the "problems" writing group emphasized the expression and processing of worries and concerns, the instructions for the "hobbies" writing group emphasized distraction from worries and concerns by writing about hobbies and interests, the "no writing" group were not given a writing task. The "problems" writing group reported shorter sleep onset latency compared to the "no writing" group. The results of this pilot study highlight the potential of research exploring the utility of a Pennebaker-style writing intervention for improving sleep.
This paper presents an application of the local activity theory [Chua, 1998] to a specific reaction–diffusion cellular nonlinear network (CNN) with cells defined by a trimolecular model, called the Brusselator. Both the local activity domain and a subset called the "edge of chaos" are identified in the cell parameter space. Within these domains, various cell parameter points were selected to illustrate the effectiveness of the local activity theory in choosing the parameters for the emergence of complex (static and dynamic) patterns in a homogeneous lattice formed by coupled locally active cells.
We present a new routing protocol, pathlet routing, in which networks advertise fragments of paths, called pathlets, that sources concatenate into end-to-end source routes. Intuitively, the pathlet is a highly flexible building block, capturing policy constraints as well as enabling an exponentially large number of path choices. In particular, we show that pathlet routing can emulate the policies of BGP, source routing, and several recent multipath proposals. This flexibility lets us address two major challenges for Internet routing: scalability and source-controlled routing. When a router's routing policy has only "local" constraints, it can be represented using a small number of pathlets, leading to very small forwarding tables and many choices of routes for senders. Crucially, pathlet routing does not impose a global requirement on what style of policy is used, but rather allows multiple styles to coexist. The protocol thus supports complex routing policies while enabling and incentivizing the adoption of policies that yield small forwarding plane state and a high degree of path choice.
