Identification of novel mutations in X-linked retinitis pigmentosa families and implications for diagnostic testing

Contains fulltext : 69886.pdf (publisher's version ) (Open Access)PURPOSE: The goal of this study was to identify mutations in X-chromosomal genes associated with retinitis pigmentosa (RP) in patients from Germany, The Netherlands, Denmark, and Switzerland. METHODS: In addition to all coding exons of RP2, exons 1 through 15, 9a, ORF15, 15a and 15b of RPGR were screened for mutations. PCR products were amplified from genomic DNA extracted from blood samples and analyzed by direct sequencing. In one family with apparently dominant inheritance of RP, linkage analysis identified an interval on the X chromosome containing RPGR, and mutation screening revealed a pathogenic variant in this gene. Patients of this family were examined clinically and by X-inactivation studies. RESULTS: This study included 141 RP families with possible X-chromosomal inheritance. In total, we identified 46 families with pathogenic sequence alterations in RPGR and RP2, of which 17 mutations have not been described previously. Two of the novel mutations represent the most 3'-terminal pathogenic sequence variants in RPGR and RP2 reported to date. In exon ORF15 of RPGR, we found eight novel and 14 known mutations. All lead to a disruption of open reading frame. Of the families with suggested X-chromosomal inheritance, 35% showed mutations in ORF15. In addition, we found five novel mutations in other exons of RPGR and four in RP2. Deletions in ORF15 of RPGR were identified in three families in which female carriers showed variable manifestation of the phenotype. Furthermore, an ORF15 mutation was found in an RP patient who additionally carries a 6.4 kbp deletion downstream of the coding region of exon ORF15. We did not identify mutations in 39 sporadic male cases from Switzerland. CONCLUSIONS: RPGR mutations were confirmed to be the most frequent cause of RP in families with an X-chromosomal inheritance pattern. We propose a screening strategy to provide molecular diagnostics in these families

On vector languages

The family of vector languages properly contains all context-free languages. For vector languages the emptiness and finiteness problems are proved to be decidable. The Parikh mapping of a vector language is shown to be semilinear

On the complexity of regulated context-free rewriting

Some complexity measures which are well-known for context-free languages are generalized in order to classify matrix languages and programmed languages. It is shown that the complexity of some context-free languages decreases if they are generated by matrix grammars or programmed grammars. An arithmetic characterization is given for infinite languages generated by two matrices. The number of matrices (as a complexity measure) is shown to be independent from any other complexity measure regarded in this paper

Informed haar-like features improve pedestrian detection

We propose a simple yet effective detector for pedestrian detection. The basic idea is to incorporate common sense and everyday knowledge into the design of simple and computationally efficient features. As pedestrians usually appear up-right in image or video data, the problem of pedestrian detection is considerably simpler than general purpose people detection. We therefore employ a statistical model of the up-right human body where the head, the upper body, and the lower body are treated as three distinct components. Our main contribution is to systematically design a pool of rectangular templates that are tailored to this shape model. As we incorporate different kinds of low-level measurements, the resulting multi-modal & multi-channel Haar-like features represent characteristic differences between parts of the human body yet are robust against variations in clothing or environmental settings. Our approach avoids exhaustive searches over all possible configurations of rectangle features and neither relies on random sampling. It thus marks a middle ground among recently published techniques and yields efficient low-dimensional yet highly discriminative features. Experimental results on the INRIA and Caltech pedestrian datasets show that our detector reaches state-of-the-art performance at low computational costs and that our features are robust against occlusions

3D-Partikelfilter SLAM

In diesem Artikel wird ein Verfahren zur Erstellung von 3D Punktwolkenkarten der Umgebung vorgestellt, das während der Fahrt aufgenommene Laserentfernungsmessungen verarbeitet. Dabei werden die vollen sechs Freiheitsgrade in der Roboterposition beachtet. Es wird ein partikelfilterbasierter Ansatz verfolgt, der FastSLAM und ähnliche Ansätze aus dem Zweidimensionalen ins Dreidimensionale überträgt. Hierbei werden insbesondere Methoden zur Handhabung der erhöhten Komplexität durch die zusätzlichen Freiheitsgrade und des erhöhten Speicheraufwandes vorgestellt. Des Weiteren kommt das Verfahren mit Odometriebewegungsdaten aus und ist nicht auf zusätzliche Bewegungssensoren angewiesen. Abschließend wird das Verfahren zur Evaluation sowohl auf Simulationsals auch auf Realdaten angewendet

Adhering to terrain characteristics for position estimation of mobile robots

Outdoor environments bear the problem of different terrains along with changing driving properties. Therefore, compared to indoor environments, the kinematics of mobile robots is much more complex. In this paper we present a comprehensive approach to learn the function of outdoor kinematics for mobile robots. Future robot positions are estimated by employing Gaussian process regression (GPR) in combination with an Unscented Kalman filter (UKF). Our approach uses optimized terrain models according to the classification of the current terrain - accomplished through Gaussian process classification (GPC) and a second order Bayesian filter (BF). Experiments showed our approach to provide more accurate estimates compared to single terrain model methods, as well as to be competitive to other dynamic approaches