Spectral theorem for the Lindblad equation for quadratic open fermionic systems

The spectral theorem is proven for the quantum dynamics of quadratic open systems of n fermions described by the Lindblad equation. Invariant eigenspaces of the many-body Liouvillean dynamics and their largest Jordan blocks are explicitly constructed for all eigenvalues. For eigenvalue zero we describe an algebraic procedure for constructing (possibly higher dimensional) spaces of (degenerate) non-equilibrium steady states.Comment: 19 pages, no figure

Self-supervised automated wrapper generation for weblog data extraction

Data extraction from the web is notoriously hard. Of the types of resources available on the web, weblogs are becoming increasingly important due to the continued growth of the blogosphere, but remain poorly explored. Past approaches to data extraction from weblogs have often involved manual intervention and suffer from low scalability. This paper proposes a fully automated information extraction methodology based on the use of web feeds and processing of HTML. The approach includes a model for generating a wrapper that exploits web feeds for deriving a set of extraction rules automatically. Instead of performing a pairwise comparison between posts, the model matches the values of the web feeds against their corresponding HTML elements retrieved from multiple weblog posts. It adopts a probabilistic approach for deriving a set of rules and automating the process of wrapper generation. An evaluation of the model is conducted on a dataset of 2,393 posts and the results (92% accuracy) show that the proposed technique enables robust extraction of weblog properties and can be applied across the blogosphere for applications such as improved information retrieval and more robust web preservation initiatives

Asymptotic Entanglement and Lindblad Dynamics: a Perturbative Approach

We consider an open bipartite quantum system with dissipative Lindblad type dynamics. In order to study the entanglement of the stationary states, we develop a perturbative approach and apply it to the physically significant case when a purely dissipative perturbation is added to the unperturbed generator which by itself would produce reversible unitary dynamics.Comment: 15 page

Ethyl Glucuronide in Scalp and Non-head Hair: An Intra-individual Comparison

Aims: Analysis of ethyl glucuronide (EtG), a minor metabolite of ethanol, is a valid tool for the assessment of social and chronic excessive alcohol consumption. Standardized analysis of EtG is usually done in head hair. As head hair cannot always be provided, alternative hair matrices become more and more interesting. Therefore, a study was performed that compared the intra-individual EtG concentrations in scalp hair and non-head hair (chest, arm, leg and axillary hair). Methods: Hair samples were collected from 68 subjects undergoing an expert assessment for fitness to drive. Aqueous extracts of the hair matrix were cleaned by solid-phase extraction, using an Oasis MAX column. EtG was first derivatized with perfluoropentanoic anhydride and then quantified by GC-MS/MS in negative chemical ionization mode, using EtG-d5 as internal standard. Results: For categorizing drinking behaviour, the two EtG cut-off values recommended by the Society of Hair Testing were applied for all different hair types. For chest, arm and leg hair, correct classification ratios were >83%. This corresponds to sensitivity values >78% and specificities >75%. Such values indicate together with φ coefficients (rφ) > 0.7 a high correlation of the categorization of the drinking behaviour based on these body hair EtG concentrations compared with the indexing based on scalp hair EtG-values. However, it must be taken into consideration that the time frame represented by non-head hair may extend way back. Conclusions: These results indicate that chest, arm and leg hair can be a valid alternative to assess the drinking behaviour of a subject if head hair is not available; whereas axillary hair is not suitable as alternative matri

Gene identification for the cblD defect of vitamin B12 metabolism

Background Vitamin B12 (cobalamin) is an essential cofactor in several metabolic pathways. Intracellular conversion of cobalamin to its two coenzymes, adenosylcobalamin in mitochondria and methylcobalamin in the cytoplasm, is necessary for the homeostasis of methylmalonic acid and homocysteine. Nine defects of intracellular cobalamin metabolism have been defined by means of somatic complementation analysis. One of these defects, the cblD defect, can cause isolated methylmalonic aciduria, isolated homocystinuria, or both. Affected persons present with multisystem clinical abnormalities, including developmental, hematologic, neurologic, and metabolic findings. The gene responsible for the cblD defect has not been identified. Methods We studied seven patients with the cblD defect, and skin fibroblasts from each were investigated in cell culture. Microcell-mediated chromosome transfer and refined genetic mapping were used to localize the responsible gene. This gene was transfected into cblD fibroblasts to test for the rescue of adenosylcobalamin and methylcobalamin synthesis. Results The cblD gene was localized to human chromosome 2q23.2, and a candidate gene, designated MMADHC (methylmalonic aciduria, cblD type, and homocystinuria), was identified in this region. Transfection of wild-type MMADHC rescued the cellular phenotype, and the functional importance of mutant alleles was shown by means of transfection with mutant constructs. The predicted MMADHC protein has sequence homology with a bacterial ATP-binding cassette transporter and contains a putative cobalamin binding motif and a putative mitochondrial targeting sequence. Conclusions Mutations in a gene we designated MMADHC are responsible for the cblD defect in vitamin B12 metabolism. Various mutations are associated with each of the three biochemical phenotypes of the disorder

Elevated serum biotinidase activity in hepatic glycogen storage disorders-A convenient biomarker

Summary: An elevated serum biotinidase activity in patients with glycogen storage disease (GSD) type Ia has been reported previously. The aim of this work was to investigate the specificity of the phenomenon and thus we expanded the study to other types of hepatic GSDs. Serum biotinidase activity was measured in a total of 68 GSD patients and was compared with that of healthy controls (8.7 ±10; range 7.0-10.6mU/ml; n=6). We found an increased biotinidase activity in patients with GSD Ia (17.7 ±3.9; range: 11.4-24.8; n=21), GSD I non-a (20.9 ±5.6; range 14.6-26.0; n=4), GSD III (12.5 ±-3.6; range 7.8-19.1; n=3), GSD VI (15.4 ±-2.0; range 14.1-17.7; n=) and GSD IX (14.0 ±-3.8; range: 7.5-21.6; n=22). The sensitivity of this test was 100% for patients with GSD Ia, GSD I non-a and GSD VI, 62% for GSD III, and 77% for GSD IX, indicating reduced sensitivity for GSD III and GSD IX, respectively. In addition, we found elevated biotinidase activity in all sera from 5 patients with Fanconi-Bickel Syndrome (15.3 ±-3.7; range 11.0-19.4). Taken together, we propose serum biotinidase as a diagnostic biomarker for hepatic glycogen storage disorder

Deep Learning using K-space Based Data Augmentation for Automated Cardiac MR Motion Artefact Detection

Quality assessment of medical images is essential for complete automation of image processing pipelines. For large population studies such as the UK Biobank, artefacts such as those caused by heart motion are problematic and manual identification is tedious and time-consuming. Therefore, there is an urgent need for automatic image quality assessment techniques. In this paper, we propose a method to automatically detect the presence of motion-related artefacts in cardiac magnetic resonance (CMR) images. As this is a highly imbalanced classification problem (due to the high number of good quality images compared to the low number of images with motion artefacts), we propose a novel k-space based training data augmentation approach in order to address this problem. Our method is based on 3D spatio-temporal Convolutional Neural Networks, and is able to detect 2D+time short axis images with motion artefacts in less than 1ms. We test our algorithm on a subset of the UK Biobank dataset consisting of 3465 CMR images and achieve not only high accuracy in detection of motion artefacts, but also high precision and recall. We compare our approach to a range of state-of-the-art quality assessment methods.Comment: Accepted for MICCAI2018 Conferenc

Accept/Reject Criteria for Structural Ceramics: Probablistic Models for Inclusion Initiated Fracture in Ceramics

Fracture tests on hot-pressed silicon nitride containing several types of inclusions have been conducted. Fracture models pertinent to each inclusion type have been proposed and correlated with the data. The resultant fracture probability relations are one of the key inputs to accept/reject decisions for nondestructive failure prediction