Construction of extremal local positive-operator-valued measures under symmetry

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Vacuum Fluctuations, Geometric Modular Action and Relativistic Quantum Information Theory

A summary of some lines of ideas leading to model-independent frameworks of relativistic quantum field theory is given. It is followed by a discussion of the Reeh-Schlieder theorem and geometric modular action of Tomita-Takesaki modular objects associated with the quantum field vacuum state and certain algebras of observables. The distillability concept, which is significant in specifying useful entanglement in quantum information theory, is discussed within the setting of general relativistic quantum field theory.Comment: 26 pages. Contribution for the Proceedings of a Conference on Special Relativity held at Potsdam, 200

Acute type B aortic dissection : does aortic arch involvement affect management and outcomes? Insights from the International Registry of Acute Aortic Dissection (IRAD)

BACKGROUND - Stanford Type B acute aortic dissection (TB-AAD) spares the ascending aorta and is optimally managed with medical therapy in the absence of complications. However, the treatment of TB-AAD with aortic arch involvement (AAI) remains an unresolved issue. METHODS AND RESULTS - We examined 498 patients with TB-AAD enrolled in the International Registry of Acute Aortic Dissection (IRAD) between 1996 and 2003. Kaplan-Meier mortality curves were constructed and multivariate regression models were performed to identify independent predictors of AAI and to evaluate whether AAI was an independent predictor of follow-up mortality. We found that 371 (74.5%) patients with TB-AAD did not have AAI versus 127 (25.5%) with AAI. Independent predictors of AAI were a history of previous aortic surgery (OR 3.4; 95% CI, 1.6 to 7.6; P=0.002), absence of back pain (OR 1.6; 95% CI, 1.1 to 2.5; P=0.05), and any pulse deficit (1.9; 95% CI, 1.1 to 3.3, P=0.03). Mortality for patients without AAI was 9.4%\ub14.3% and 21.0%\ub16.9% at 1 and 3 years versus 9.2%\ub17.7% and 19.9%\ub111.1% with AAI, respectively (mean follow-up overall, 2.3 years, log rank P=0.82). AAI was not an independent predictor of long-term mortality. CONCLUSIONS - Patients with TB-AAD and aortic arch involvement do not differ with regards to mortality at 3 years. Whether or not AAI involvement impacts other measures of morbidity such as freedom from operation or endovascular intervention deserves further study

Shape Refinement through Explicit Heap Analysis

Shape analysis is a promising technique to prove program properties about recursive data structures. The challenge is to automatically determine the data-structure type, and to supply the shape analysis with the necessary information about the data structure. We present a stepwise approach to the selection of instrumentation predicates for a TVLA-based shape analysis, which takes us a step closer towards the fully automatic verification of data structures. The approach uses two techniques to guide the refinement of shape abstractions: (1) during program exploration, an explicit heap analysis collects sample instances of the heap structures, which are used to identify the data structures that are manipulated by the program; and (2) during abstraction refinement along an infeasible error path, we consider different possible heap abstractions and choose the coarsest one that eliminates the infeasible path. We have implemented this combined approach for automatic shape refinement as an extension of the software model checker BLAST. Example programs from a data-structure library that manipulate doubly-linked lists and trees were successfully verified by our tool

Linear Time Algorithm for the Generalised Longest Common Repeat Problem

Given a set of strings U = {T1,T2,...,Tℓ}, the longest common repeat problem is to find the longest common substring that appears at least twice in each string of U, considering direct, inverted, mirror as well as everted repeats. In this paper we define the generalised longest common repeat problem, where we can set the number of times that a repeat should appear in each string. We present a linear time algorithm for this problem using the suffix array. We also show an application of our algorithm for finding a longest common substring which appears only in a subset U ′ of U but not in U−U ′