Ensemble Kalman methods for high-dimensional hierarchical dynamic space-time models

We propose a new class of filtering and smoothing methods for inference in high-dimensional, nonlinear, non-Gaussian, spatio-temporal state-space models. The main idea is to combine the ensemble Kalman filter and smoother, developed in the geophysics literature, with state-space algorithms from the statistics literature. Our algorithms address a variety of estimation scenarios, including on-line and off-line state and parameter estimation. We take a Bayesian perspective, for which the goal is to generate samples from the joint posterior distribution of states and parameters. The key benefit of our approach is the use of ensemble Kalman methods for dimension reduction, which allows inference for high-dimensional state vectors. We compare our methods to existing ones, including ensemble Kalman filters, particle filters, and particle MCMC. Using a real data example of cloud motion and data simulated under a number of nonlinear and non-Gaussian scenarios, we show that our approaches outperform these existing methods

Microscopes and computers combined for analysis of chromosomes

Scanning machine CHLOE, developed for photographic use, is combined with a digital computer to obtain quantitative and statistically significant data on chromosome shapes, distribution, density, and pairing. CHLOE permits data acquisition about a chromosome complement to be obtained two times faster than by manual pairing

Fractional vortices in the XY model with π\pi bonds

We define a new set of excitations in the XY model which we call ``fractional vortices''. In the frustrated XY model containing $\pi$ bonds, we make the ansatz that the ground state configurations can be characterized by pairs of oppositely charged fractional vortices. For a chain of $\pi$ bonds, the ground state energy and the phase configurations calculated on the basis of this ansatz agree well with the results from direct numerical simulations. Finally, we discuss the possible connection of these results to some recent experiments by Kirtley {\it et al} [Phys. Rev. B {\bf 51}, R12057 (1995)] on high-T$_c$ superconductors where fractional flux trapping was observed along certain grain boundaries.Comment: 13 pages, 14 figures included (.eps). No essential differences to previous version, however more compact forma

A multinomial quadrivariate D-vine copula mixed model for meta-analysis of diagnostic studies in the presence of non-evaluable subjects

Diagnostic test accuracy studies observe the result of a gold standard procedure that defines the presence or absence of a disease and the result of a diagnostic test. They typically report the number of true positives, false positives, true negatives and false negatives. However, diagnostic test outcomes can also be either non-evaluable positives or non-evaluable negatives. We propose a novel model for the meta-analysis of diagnostic studies in the presence of non-evaluable outcomes, which assumes independent multinomial distributions for the true and non-evaluable positives, and, the true and non-evaluable negatives, conditional on the latent sensitivity, specificity, probability of non-evaluable positives and probability of non-evaluable negatives in each study. For the random effects distribution of the latent proportions, we employ a drawable vine copula that can successively model the dependence in the joint tails. Our methodology is demonstrated with an extensive simulation study and applied to data from diagnostic accuracy studies of coronary computed tomography angiography for the detection of coronary artery disease. The comparison of our method with the existing approaches yields findings in the real data application that change the current conclusions

Effect of bow-type initial imperfection on the buckling load and mass of graphite-epoxy blade-stiffened panels

A structural synthesis computer code which accounts for first order effects of an initial bow and which can be used for sizing stiffened composite panels having an arbitrary cross section is used to study graphite blade-stiffened panels. The effect of a small initial bow on both the load carrying ability of panels and on the mass of panels designed to carry a specified load is examined. Large reductions in the buckling load caused by a small initial bow emphasize the need for considering a bow when a panel is designed

Politicizing Patents - Patenting Biotechnology in the Wake of Section 33, Prometheus, and CLS Bank

Tucked into the America Invents Act is the first statutory exemption for any patentable subject matter. Section 33 renders unpatentable all claims “encompassing a human being.” By recognizing a vague subject matter – exception for human beings despite the fact that internal policies had long militated against such patent claims, Congress has politicized the patent law to an unheard-of degree. While textually consistent with internal USPTO policy, the passage of § 33 should not be seen as an invitation to litigators to expand § 101 unpatentable-subject-matter challenges to validity by including arguments that medical methods, genetic tests, biological chimeras, or emerging cell and tissue therapies are now unpatentable, particularly in light of the recent Prometheus Supreme Court decision. The Federal Circuit’s recent decision in CLS Bank undercuts this argument. As the U.S. Court of Appeals for the Federal Circuit and the U.S. Supreme Court have both long held, living subject matter is a valuable part of the United States’ biotechnology industry. This exception is limited to only those patents that encompass an entire human being, thus exempting patents on genetic modifications to cells, tissues, organs, bones, genes, zygotes, and treatments. Only then can we ensure innovation, certainty, and profitability in the lucrative and promising area of biotechnology, ensure that the United States remains competitive in the international market, and recognize that it is not the province of the Patent and Trademark Office or the patent laws to be embroiled in a political conflict that is irrelevant to innovation

The China Syndrome: The International Trade Commission’s Rising Importance for Enforcing International Trade Secret Violations

Reprinted with permission of FDL

Effect of the chemical state of pyrolysis gases on heat-shield mass

Effect of chemical properties of pyrolysis gases on heat shield mass required for lifting reentry vehicle in typical reentry trajector