The cross-sectional GRAS sample: A comprehensive phenotypical data collection of schizophrenic patients

<p>Abstract</p> <p>Background</p> <p>Schizophrenia is the collective term for an exclusively clinically diagnosed, heterogeneous group of mental disorders with still obscure biological roots. Based on the assumption that valuable information about relevant genetic and environmental disease mechanisms can be obtained by association studies on patient cohorts of ≥ 1000 patients, if performed on detailed clinical datasets and quantifiable biological readouts, we generated a new schizophrenia data base, the GRAS (Göttingen Research Association for Schizophrenia) data collection. GRAS is the necessary ground to study genetic causes of the schizophrenic phenotype in a 'phenotype-based genetic association study' (PGAS). This approach is different from and complementary to the genome-wide association studies (GWAS) on schizophrenia.</p> <p>Methods</p> <p>For this purpose, 1085 patients were recruited between 2005 and 2010 by an invariable team of traveling investigators in a cross-sectional field study that comprised 23 German psychiatric hospitals. Additionally, chart records and discharge letters of all patients were collected.</p> <p>Results</p> <p>The corresponding dataset extracted and presented in form of an overview here, comprises biographic information, disease history, medication including side effects, and results of comprehensive cross-sectional psychopathological, neuropsychological, and neurological examinations. With >3000 data points per schizophrenic subject, this data base of living patients, who are also accessible for follow-up studies, provides a wide-ranging and standardized phenotype characterization of as yet unprecedented detail.</p> <p>Conclusions</p> <p>The GRAS data base will serve as prerequisite for PGAS, a novel approach to better understanding 'the schizophrenias' through exploring the contribution of genetic variation to the schizophrenic phenotypes.</p

Antwortsicherheiten als Maß für die metakognitive Überwachung bei Grundschulkindern? (Eingeschränkte)Validität bei der Vorhersage schulischer Leistungen und die mediierende Rolle des Selbstkonzepts

Stankov and Lee (2008) have shown confidence scores to have unique predictive effects on achievement criteria when the corresponding test scores are controlled. These findings suggest that confidence scores might provide valid indicators of metacognitive monitoring. However, as confidence is related to self-concept (Kröner u. Biermann, 2007), it is possible that the unique predictive effects disappear when self-concept is also controlled. This study examines whether average confidence regarding performance on the items of a spelling test showed incremental validity above and beyond the corresponding test scores in predicting academic achievement with and without control for verbal self-concept. N = 414 10-year-olds from 22 fourth grade classes in Bavarian primary schools participated in the research project. Students’ confidence ratings were shown to correlate with corresponding test scores. Furthermore, when test scores were controlled, average confidence scores had unique predictive effects on academic achievement. When both test scores and self-concept were controlled, however, there was no substantial unique predictive effect of confidence. Thus, the predictive power of primary students’ confidence ratings may result from their correlation with self-concept. (DIPF/Orig.)Wie Stankov und Lee (2008) zeigten, wiesen Antwortsicherheiten inkrementelle Validität in Bezug auf externe Leistungskriterien auch nach Kontrolle der Leistung auf, anhand der die Antwortsicherheiten erhoben wurden. Dies lässt sich so interpretieren, dass Antwortsicherheiten valide Indikatoren für die metakognitive Überwachung sind. Da die Antwortsicherheiten aber mit dem Selbstkonzept korreliert sind (Kröner u. Biermann, 2007), könnte ihre inkrementelle Validität verschwinden, wenn zusätzlich Effekte des Selbstkonzepts kontrolliert werden. Dies wurde in der vorliegenden Studie untersucht, indem aggregierte Antwortsicherheiten und Testleistungen in einem Rechtschreibtest als Prädiktoren schulischer Leistungen verwendet wurden, und zwar mit und ohne Kontrolle des Selbstkonzepts im Fach Deutsch. Es nahmen N = 414 zehnjährige Kinder aus 22 vierten Klassen bayerischer Grundschulen an dieser Studie teil. Es zeigte sich, dass auch bei den untersuchten Grundschulkindern Antwortsicherheiten mit der jeweiligen Testleistung korrelierten. Außerdem wiesen sie inkrementelle Validität in Bezug auf schulische Leistungen auf, und zwar auch bei Kontrolle der Rechtschreibleistung. Wenn jedoch darüber hinaus Effekte des Selbstkonzepts kontrolliert wurden, verschwand dieser Effekt. Dies deutet darauf hin, dass der Erklärungswert von Antwortsicherheiten für externe Leistungskriterien auf ihre Korrelation mit dem Selbstkonzept zurückgeht. (DIPF/Orig.

Edge Preserving Noise Smoothing with an Optimized Cubic Filter

A cubic polynomial filter is presented for edge preserving noise smoothing. The filter coefficients are adaptable and can be optimized to improve the filter result. Experiments show that the image quality achieved with the optimized cubic filter is comparable to that of a more complex rational filter. 1 Introduction The idea of edge preserving noise smoothing consists in smoothing the noise of a distorted image while leaving the edges and fine structures of the image intact. Many approaches to this task can be found in the literature [1]. Some are based on order statistics [5, 10], others use adaptive averaging masks that take into account only pixels with similar luminance values [7, 3] or combinations of both methods [4]. In [8] Ramponi proposed a rational filter for image smoothing. It showed a considerable improvement of the mean square error between the filtered image and the noise free image compared to the results achieved with the above mentioned methods. However, the design o..

Design Constraints For Polynomial And Rational Filters

Polynomial and rational filters for image enhancement, edge preserving noise smoothing, and interpolation of encoded images are usually designed as a weighted combination of nonlinear filters having lowpass or highpass behaviour. The choice of the filter components and of the coefficients is performed heuristically, though. In this paper general design constraints for polynomial and rational filters are presented that are necessary to achieve isotropy, the preservation of the expectation value, and the detection of edges. For the application of edge preserving noise smoothing a method is derived to find an optimal polynomial or rational filter that meets these constraints. 1. INTRODUCTION Polynomial and rational filters have shown to be a successful tool for applications in image enhancement, edge preserving noise smoothing, and interpolation of encoded images [1, 4, 6, 7, 8, 9]. Their design is usually based on a weighted combination of nonlinear filters having lowpass or highpass beh..

Cell Segmentation with Adaptive Region Growing

The cell segmentation presented in this paper is part of current research work on an automated cell tracking project. Its aim is the tracking of the movement of representative cells in a 3D collagen gel in order to determine the activity of the cell after the injection of certain medical substances. A major requirement for this project is an efficient and robust method for the segmentation of cell images. Here we present an automated method based on region growing with a local adaptive threshold. For preprocessing we use an optimized rational filter for edge preserving noise smoothing. The experimental results show that the presented method is suitable for the segmentation of melanoma cells (tumor cells) as well as lymphocytes (blood cells) in a 3D collagen gel. 1. Introduction The need of quantitative analysis of cell movement is rapidly increasing. The study of cell movement and cell behavior is of fundamental importance in areas such as cell embryology, wound healing, host defense..