Digitale Bildverarbeitung spannungsoptischer Isochromatenbilder

Digitale Bildanalysesysteme bieten die Möglichkeit, Verfahren der Bildverarbeitung wirkungsvoll auch in der Spannungsoptik einzusetzen. Es wird über die Bearbeitung, insbesondere über die Filterung von spannungsoptischen Isochromatenbildern berichtet, und zwar über die Hochpaßfilterung mit anschließender Konturverstärkung, über die Gradientenfilterung mit einem Sobel-Operator und über die Skelettierung. Als Beispiel dient ein I-Träger mit nebeneinanderliegenden, ovalen Löchern unter Querkraftbelastung. Es werden Schubspannungsverteilungen für die verschiedenen Bearbeitungsmethoden dargestellt.     

Impaired innervation of cultured human muscle overexpressing betaAPP experimentally and genetically: relevance to inclusion-body myopathies

To investigate whether abnormally accumulated betaAPP may be responsible for denervation of muscle fibers that are present in hereditary inclusion-body myopathy (h-IBM) and sporadic inclusion-body myositis (s-IBM), we cultured five h-IBM and eight normal muscle biopsies. In eight other experiments, a 3 kb human 751-betaAPP-cDNA was transferred, using adenovirus vector, into cultured normal myotubes immediately after myoblast fusion. In all experiments, cultured muscle fibers were co-cultured with fetal rat spinal cord. Controls had no detectable betaAPP epitopes, whereas betaAPP epitopes were greatly increased in cultured h-IBM muscle and in cultured normal muscle after betaAPP-gene transfer. Innervated normal cultured muscle fibers were continuously contracting and fully cross-striated, and they had acetylcholine receptors (AChRs) and acetylcholinesterase (AChE) accumulated only at the neuromuscular junctions (NMJs). By contrast, both groups of betaAPP-overexpressing cultured muscle fibers were not contracting and not cross-striated; and did not have NJMs containing AChRs and AChE. Our results suggest that over-expression of betaAPP in cultured muscle fibers inhibits their innervation, and that the accumulation of betaAPP in muscle fibers of both h- and s-IBM patients may be responsible for their not becoming or remaining properly innervated or reinnervated, i.e. a 'myogenous-dysinnervation' mechanism.     

Linear mappings ofn-dimensional uniform recurrences ontok-dimensional systolic arrays

We propose two methods for the synthesis of systolic arrays from uniform recurrence equations. First, we discuss a synthesis method for mappingn-dimensional uniform recurrence equations ontok-dimensional systolic arrays with a two-dimensional system clock. In this method we are led by the idea that all space-time conflicts caused by a scalar valued causal timing function and an allocation function can be rule out by a second scalar valued timing function. Stacking both timing functions yields a two-dimensional clock. Second, we develop a method to synthesizek-dimensional arrays with a scalar valued clock from a large subclass ofn-dimensional uniform recurrence equations containing important algorithms from signal and image processing. This method is based on a decomposition of the domain of the uniform recurrence equations into subdomains according to a given procesor allocation which allows the construction of a timing function for the whole domain from timing functions for the subdomains. In this way, the problem of finding optimal timing functions is reduced to finding optimal functions for the subdomains which are usually easier to establish. This synthesis method exhibits simplicity but its drawback lies in its limited applicability.     

Depressive symptom patterns among older women.

The structure of depressive symptom patterns was investigated in a community sample of 344 women between the ages of 51 and 92 who were administered the SCL-90—R Depression and Additional Symptoms Scales. Confirmatory factor analysis was used to test alternative measurement hypotheses implied by clinical formulations of depressive symptom patterns among elderly persons. The findings show support for the hypothesis that 2 somewhat different depressive syndromes, along with 4 more delimited forms of distress, underlie symptom-reporting patterns. Implications of these findings for future research on the relation between aging and depression are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The kernel recursive least-squares algorithm

We present a nonlinear version of the recursive least squares (RLS) algorithm. Our algorithm performs linear regression in a high-dimensional feature space induced by a Mercer kernel and can therefore be used to recursively construct minimum mean-squared-error solutions to nonlinear least-squares problems that are frequently encountered in signal processing applications. In order to regularize solutions and keep the complexity of the algorithm bounded, we use a sequential sparsification process that admits into the kernel representation a new input sample only if its feature space image cannot be sufficiently well approximated by combining the images of previously admitted samples. This sparsification procedure allows the algorithm to operate online, often in real time. We analyze the behavior of the algorithm, compare its scaling properties to those of support vector machines, and demonstrate its utility in solving two signal processing problems-time-series prediction and channel equalization.     

Light particle detection by BGO scintillators with photodiode readout

The applicability of a BGO crystal coupled to a photodiode for detection of light charged particles in the energy range of 5–170 MeV has been investigated. Energy resolution, light output and scintillation efficiency have been deduced from the data.