Positive Polynomials on Riesz Spaces

We prove some properties of positive polynomial mappings between Riesz spaces, using finite difference calculus. We establish the polynomial analogue of the classical result that positive, additive mappings are linear. And we prove a polynomial version of the Kantorovich extension theorem.Comment: 12 page

A new quantum version of f-divergence

This paper proposes and studies new quantum version of $f$-divergences, a class of convex functionals of a pair of probability distributions including Kullback-Leibler divergence, Rnyi-type relative entropy and so on. There are several quantum versions so far, including the one by Petz. We introduce another quantum version ($\mathrm{D}_{f}^{\max}$, below), defined as the solution to an optimization problem, or the minimum classical $f$- divergence necessary to generate a given pair of quantum states. It turns out to be the largest quantum $f$-divergence. The closed formula of $\mathrm{D}_{f}^{\max}$ is given either if $f$ is operator convex, or if one of the state is a pure state. Also, concise representation of $\mathrm{D}_{f}^{\max}$ as a pointwise supremum of linear functionals is given and used for the clarification of various properties of the quality. Using the closed formula of $\mathrm{D}_{f}^{\max}$, we show: Suppose $f$ is operator convex. Then the\ maximum $f\,$- divergence of the probability distributions of a measurement under the state $\rho$ and $\sigma$ is strictly less than $\mathrm{D}_{f}^{\max}\left( \rho\Vert\sigma\right)$. This statement may seem intuitively trivial, but when $f$ is not operator convex, this is not always true. A counter example is $f\left( \lambda\right) =\left\vert 1-\lambda\right\vert$, which corresponds to total variation distance. We mostly work on finite dimensional Hilbert space, but some results are extended to infinite dimensional case.Comment: The proof of dual representation of the former version was misstated. An alternative proof is presente

Holomorphic functions on complex Banach lattices

We introduce and study the algebraic, analytic and lattice properties of regular homogeneous polynomials and holomorphic functions on complex Banach lattices. We show that the theory of power series with regular terms is closer to the theory of functions of several complex variables than the theory of holomorphic functions on Banach spaces. We extend the concept of the Bohr radius to Banach lattices and show that it provides us with a lower bound for the ratio between the radius of regular convergence and the radius of convergence of a regular holomorphic function. This allows us to show that the radius of regular convergence coincides with the radius of convergence for holomorphic functions on finite dimensional spaces and orthogonally additive holomorphic functions but that these radii can be radically different on $\ell_p$ for $p>1$

Finite difference time domain modeling of steady state scattering from jet engines with moving turbine blades

The approach chosen to model steady state scattering from jet engines with moving turbine blades is based upon the Finite Difference Time Domain (FDTD) method. The FDTD method is a numerical electromagnetic program based upon the direct solution in the time domain of Maxwell's time dependent curl equations throughout a volume. One of the strengths of this method is the ability to model objects with complicated shape and/or material composition. General time domain functions may be used as source excitations. For example, a plane wave excitation may be specified as a pulse containing many frequencies and at any incidence angle to the scatterer. A best fit to the scatterer is accomplished using cubical cells in the standard cartesian implementation of the FDTD method. The material composition of the scatterer is determined by specifying its electrical properties at each cell on the scatterer. Thus, the FDTD method is a suitable choice for problems with complex geometries evaluated at multiple frequencies. It is assumed that the reader is familiar with the FDTD method

Fidelity enhancement by logical qubit encoding

We demonstrate coherent control of two logical qubits encoded in a decoherence free subspace (DFS) of four dipolar-coupled protons in an NMR quantum information processor. A pseudo-pure fiducial state is created in the DFS, and a unitary logical qubit entangling operator evolves the system to a logical Bell state. The four-spin molecule is partially aligned by a liquid crystal solvent, which introduces strong dipolar couplings among the spins. Although the system Hamiltonian is never fully specified, we demonstrate high fidelity control over the logical degrees of freedom. In fact, the DFS encoding leads to higher fidelity control than is available in the full four-spin Hilbert space.Comment: 10 pages, 2 figure

Outcomes of acute versus subacute scapholunate ligament repair

PURPOSE: This study investigated the long-term outcomes of direct scapholunate ligament (SLL) repairs with or without dorsal capsulodesis performed within 6 weeks (acute repair) of a SLL tear versus 6 to 12 weeks following injury (subacute repair). METHODS: A review of medical records from April 1996 to April 2012 identified 24 patients who underwent SLL repair (12 acute, 12 subacute). Patients returned to the clinic for radiographic examinations of the injured wrist, standardized physical examinations, and validated questionnaires. RESULTS: The mean follow-up times for the acute and subacute groups were 7.2 and 6.2 years, respectively. At the final examination, patients with acute surgery regained more wrist extension (acute = 55°, subacute = 47°). The total wrist flexion-extension arcs, grip strengths, pinch strengths, and patient-rated outcome scores were found to be similar between groups. The final scapholunate gap, scapholunate angle, and the prevalence of arthritis were also found to be similar between the acute and subacute groups. CONCLUSIONS: Although SLL repair is more commonly recommended for treatment of acute SLL injuries, there were no significant long-term differences between acute and subacute SLL surgeries (repair ± capsulodesis). TYPE OF STUDY/LEVEL OF EVIDENCE: Prognostic III

Hand problems among endourologists.

BACKGROUND AND PURPOSE: Endourology has evolved rapidly for the management of both benign and malignant disease of the upper urinary tract. Limited data exist, however, on the occupational hazards posed by complex endourologic procedures. The aim of this study was to determine the prevalence and possible causes of hand problems among endourologists who routinely perform flexible ureteroscopy compared with controls. MATERIALS AND METHODS: An online computer survey targeted members of the Endourological Society and psychiatrists in academic and community settings. A total of 600 endourologists and 578 psychiatrists were contacted by e-mail. Invited physicians were queried regarding their practice settings and symptoms of hand pain, neuropathy, and/or discomfort. RESULTS: Survey responses were obtained from 122 (20.3%) endourologists and 74 (12.8%) psychiatrists. Of endourologists, 61% were in an academic setting and 70% devoted their practice to endourology. Endourologists were in practice for a mean 13 years, performing 4.5 ureteroscopic cases per week with a mean operative time of 50 minutes. Hand/wrist problems were reported by 39 (32%) endourologists compared with 14 (19%) psychiatrists (P=0.0486, relative risk [RR]=1.69). Surgeons who preferred counterintuitive ureteroscope deflection were significantly more likely to have problems (56%) compared with intuitive users (27%) (RR 2.07, P=0.0139) or those with no preference (26%) (RR 2.15, P=0.0451). Overall, most respondents (85%) with hand/wrist problems needed either medical or surgical intervention. CONCLUSIONS: Hand and wrist problems are very common among endourologists. Future studies are needed to develop more ergonomic platforms and thereby reduce the endourologist\u27s exposure to these occupational hazards

Novel Algorithms Reveal Streptococcal Transcriptomes and Clues about Undefined Genes

Bacteria–host interactions are dynamic processes, and understanding transcriptional responses that directly or indirectly regulate the expression of genes involved in initial infection stages would illuminate the molecular events that result in host colonization. We used oligonucleotide microarrays to monitor (in vitro) differential gene expression in group A streptococci during pharyngeal cell adherence, the first overt infection stage. We present neighbor clustering, a new computational method for further analyzing bacterial microarray data that combines two informative characteristics of bacterial genes that share common function or regulation: (1) similar gene expression profiles (i.e., co-expression); and (2) physical proximity of genes on the chromosome. This method identifies statistically significant clusters of co-expressed gene neighbors that potentially share common function or regulation by coupling statistically analyzed gene expression profiles with the chromosomal position of genes. We applied this method to our own data and to those of others, and we show that it identified a greater number of differentially expressed genes, facilitating the reconstruction of more multimeric proteins and complete metabolic pathways than would have been possible without its application. We assessed the biological significance of two identified genes by assaying deletion mutants for adherence in vitro and show that neighbor clustering indeed provides biologically relevant data. Neighbor clustering provides a more comprehensive view of the molecular responses of streptococci during pharyngeal cell adherence

Local orthorhombicity in the magnetic C4C_4 phase of the hole-doped iron-arsenide superconductor Sr1−x_{1-x}Nax_{x}Fe2_2As2_2

We report temperature-dependent pair distribution function measurements of Sr$_{1-x}$Na$_{x}$Fe$_2$As$_2$, an iron-based superconductor system that contains a magnetic phase with reentrant tetragonal symmetry, known as the magnetic $C_4$ phase. Quantitative refinements indicate that the instantaneous local structure in the $C_4$ phase is comprised of fluctuating orthorhombic regions with a length scale of $\sim$2 nm, despite the tetragonal symmetry of the average static structure. Additionally, local orthorhombic fluctuations exist on a similar length scale at temperatures well into the paramagnetic tetragonal phase. These results highlight the exceptionally large nematic susceptibility of iron-based superconductors and have significant implications for the magnetic $C_4$ phase and the neighboring $C_2$ and superconducting phases