Wigner-space synthesis of discrete-time periodic signals

A procedure that facilitates at least-squares synthesis of periodic, discrete-time signals from Wigner quasi-distributions is proposed. The scheme is based on expanding the desired time sequence on a generally nonorthogonal, Gabor-type basis whose associated biorthogonal function presumably exists. The specific basis selection may crucially affect the efficiency and quality of the ensuing synthesis procedure. The cited basis type constitutes a considerable generalization over the standardly used orthogonal variety, thus creating previously unavailable degrees of freedom. Of primary significance is the acquired capability of generating time-frequency basis functions that are well localized. Localization is a highly desirable property that can advantageously serve in various applications. It is shown and numerically demonstrated that benefits of localization as well as the fact that achieving effective time-frequency basis localization renders a certain degree of oversampling unavoidable     

ACAT inhibitors derived from hetero-Diels-Alder cycloadducts of thioaldehydes

Acyl-CoA:cholesterol acyltransferase (ACAT) is the enzyme largely responsible for intracellular cholesterol esterification. A systemic inhibitor of ACAT is believed to be able to slow or even reverse the atherosclerotic process. Towards that goal, a series of cyclic sulfides, derived from the hetero-Diels-Alder reaction of thioaldehydes with 1,3-dienes, and bearing carboxamide substituents, were prepared and evaluated for in vitro (in several tissues and species) and ex vivo ACAT inhibition. Minor changes in subsequent structure were found to have a significant effect in optimization of the biological activity of this series of compounds.     

Assignment Games with Conflicts: Robust Price of Anarchy and Convergence Results via Semi-Smoothness

We study assignment games in which jobs select machines, and in which certain pairs of jobs may conflict, which is to say they may incur an additional cost when they are both assigned to the same machine, beyond that associated with the increase in load. Questions regarding such interactions apply beyond allocating jobs to machines: when people in a social network choose to align themselves with a group or party, they typically do so based upon not only the inherent quality of that group, but also who amongst their friends (or enemies) chooses that group as well. We show how semi-smoothness, a recently introduced generalization of smoothness, is necessary to find tight bounds on the robust price of anarchy, and thus on the quality of correlated and Nash equilibria, for several natural job-assignment games with interacting jobs. For most cases, our bounds on the robust price of anarchy are either exactly 2 or approach 2. We also prove new convergence results implied by semi-smoothness for our games. Finally we consider coalitional deviations, and prove results about the existence and quality of strong equilibrium.     

High Speed Particle Beam Generation: A Dynamic Focusing Mechanism for Selecting Ultrafine Particles

RSMS-II is a unique characterization technique for analyzing the chemical content of individual airborne ultrafine particles in real time. Although based on earlier versions, the newest implementation offers crucial enhancements including a smart data acquisition system and a completely redesigned particle inlet. The particle inlet is based on a dynamic focusing mechanism that selectively transmits a narrow particle size range in the form of a high speed particle beam. The mean particle size that is optimally transmitted is dynamically altered by changing the nozzle source pressure, thus particles over a wide size range may be selected. Inherent in the design of dynamic focusing mechanisms is the ability to size-select particles based on their aerodynamic characteristics, thus obviating the need for additional sizing components. The principle, design, and calibration of a variable pressure inlet is presented in the current work. Characteristics are estimated employing a theoretical approach based on the Stokes number definition and supported with numerical simulations using CFD tools. Results from a preliminary effort in calibrating the inlet using monodisperse aerosol are presented. Results indicate that the size resolving capability of the inlet may be enhanced at the expense of lowered transmission rates. Finally, the capability of RSMS-II as a characterization technique is demonstrated by analyzing ultrafine atmospheric particles from a moderately polluted episode.     

A new method of treatment for mallet finger. A preliminary report

An infant with a typical Edwards syndrome and a modal chromosome number of 46 is reported. In all cells analyzed one chromosome G was missing and an additional chromosome similar to a pair No. 16 was present. The phenotype of the child indicates that the extra element is a translocation between G and 18 chromosomes as in one case described previously.     

Application of the ART-2a algorithm to laser ablation aerosol mass spectrometry of particle standards

Single-particle mass spectrometers are now commonly used to analyze atmospheric particles and generate tens of thousands of spectra from typical measurement campaigns. The ART-2a spectrum algorithm has been used to classify these spectra. In this work, we generate a range of particles that are models of those that are common in the atmosphere. A single-particle mass spectrometer is used to analyze these known particles, and the spectra are classified using ART-2a. The optimum vigilance parameter is approximately 0.5 while the optimum learning rate is approximately 0.05. The classifications elucidate limitations in generation of test particles, their analysis by single-particle techniques, and their classification by ART-2a.     

Polyoxometallate-stabilized platinum catalysts on multi-walled carbon nanotubes for fuel cell applications

A novel catalyst, Pt-PMo₁₂-CNT, with well-dispersed Pt nanoparticles and monolayer PMo₁₂ on multi-walled carbon nanotubes (CNTs) is reported. A polyoxometallate (PMo₁₂) was chemically adsorbed on the surface of Pt nanoparticles and on outer walls of CNTs. These effectively prevented the agglomeration of Pt nanoparticles and CNTs due to the electrostatic repulsive interactions between negatively charged PMo₁₂ monolayers. The as-prepared Pt-PMo₁₂-CNT materials show higher electrocatalytic activity, higher cycle stability, and better tolerance to poisoning species in methanol oxidation than do Pt-CNT catalysts prepared by the same method. The reasons for the improved catalytic performance of the Pt-PMo₁₂-CNT catalysts are discussed.