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We present an approach to integrate multiple rendering back-ends under a common application layer for distributed systems. The primary goal was to find a practical and nonintrusive way to use potentially very different renderers in heterogeneous computing environments without impairing their strengths and without burdening the back-ends or the application with details of the cluster environment. Our approach is based on a mediator layer that handles multithreading, clustering, and the synchronization between the application's and the back-end's scene. We analyze the proposed approach with an implementation for a state-of-the-art distributed VR/AR system. In particular, we present two case studies and an example application. [ABSTRACT FROM AUTHOR]

The article offers information about the changes that are to be made in OpenGL, a component of interactive graphics applications. The changes are expected in three major areas. They include use of vertex buffer objects (VBOs) in geometry specification, emphasis on shaders, and the provision of changing only the data once an object is created. Although the changes are expected to offer some advantages for both a driver and an application developer, they are also expected to have an adverse impact on the backward compatibility to older versions of OpenGL.

The support for multi-threaded applications in current scene graphs is very limited, if it is supported at all. This work presents an approach for a very general multi-threading framework that allows total separation of threads without total replication of data. It also supports extensions to clusters, both for sort-first and sort-last rendering configurations. The described concepts have been implemented in the OpenSG scene graph and are widely and successfully used. [Copyright &y& Elsevier]

Sequence alignment is a common and often repeated task in molecular biology. Typical alignment operations consist of finding similarities between a pair of sequences (pairwise sequence alignment) or a family of sequences (multiple sequence alignment). The need for speeding up this treatment comes from the rapid growth rate of biological sequence databases: Every year their size increases by a factor of 1.5 to 2. In this paper we present a new approach to high-performance biological sequence alignment based on commodity PC graphics hardware. Using modern graphics processing units (GPUs) for high-performance computing is facilitated by their enhanced programmability and motivated by their attractive price/performance ratio and incredible growth in speed. To derive an efficient mapping onto this type of architecture, we have reformulated dynamic-programming-based alignment algorithms as streaming algorithms in terms of computer graphics primitives. Our experimental results show that the GPU-based approach allows speedups of more than one order of magnitude with respect to optimized CPU implementations. [ABSTRACT FROM AUTHOR]

Aims: Previous work in our lab has identified the protease kallikrein‐8 (KLK8) as a potential upstream mover in the pathogenesis of Alzheimer's disease (AD). We showed pathologically elevated levels of KLK8 in the cerebrospinal fluid and blood of patients with mild cognitive impairment or dementia due to AD, and in brains of patients and transgenic CRND8 (TgCRND8) mice in incipient stages of the disease. Furthermore, short‐term antibody‐mediated KLK8 inhibition in moderate stage disease alleviated AD pathology in female mice. However, it remains to be shown whether long‐term reversal of KLK8 overexpression can also counteract AD. Therefore, the effects of genetic Klk8‐knockdown were determined in TgCRND8 mice. Methods: The effects of heterozygous ablation of murine Klk8 (mKlk8) gene on AD pathology of both sexes were examined by crossbreeding TgCRND8 [hAPP+/−] with mKlk8‐knockdown [mKlk8+/−] mice resulting in animals with or without AD pathology which revealed pathologically elevated or normal KLK8 levels. Results: mKlk8‐knockdown had negligible effects on wildtype animals but led to significant decline of amyloid beta (Aβ) and tau pathology as well as an improvement of structural neuroplasticity in a sex‐specific manner in transgenics. These changes were mediated by a shift to non‐amyloidogenic cleavage of the human amyloid precursor protein (APP), recovery of the neurovascular unit and maintaining microglial metabolic fitness. Mechanistically, Klk8‐knockdown improved Aβ phagocytosis in primary glia and Aβ resistance in primary neurons. Most importantly, transgenic mice revealed less anxiety and a better memory performance. Conclusions: These results reinforce the potential of KLK8 as a therapeutic target in AD. [ABSTRACT FROM AUTHOR]