105 research outputs found
Batch solution of small PDEs with the OPS DSL
In this paper we discuss the challenges and optimisations opportunities when solving a large number of small, equally sized discretised PDEs on regular grids. We present an extension of the OPS (Oxford Parallel library for Structured meshes) embedded Domain Specific Language, and show how support can be added for solving multiple systems, and how OPS makes it easy to deploy a variety of transformations and optimisations. The new capabilities in OPS allow to automatically apply data structure transformations, as well as execution schedule transformations to deliver high performance on a variety of hardware platforms. We evaluate our work on an industrially representative finance simulation on Intel CPUs, as well as NVIDIA GPUs
Sporulation, bacterial cell envelopes, and the origin of life
Electron cryotomography (ECT) enables the 3D reconstruction of intact cells in a near-native state. Images produced by ECT have led to the proposal that an ancient sporulation-like event gave rise to the second membrane in diderm bacteria. Tomograms of sporulating monoderm and diderm bacterial cells show how sporulation can lead to the generation of diderm cells. Tomograms of Gram-negative and Gram-positive cell walls and purified sacculi suggest that they are more closely related than previously thought and support the hypothesis that they share a common origin. Mapping the distribution of cell envelope architectures onto a recent phylogenetic tree of life indicates that the diderm cell plan, and therefore the sporulation-like event that gave rise to it, must be very ancient. One explanation for this model is that during the cataclysmic transitions of the early Earth, cellular evolution may have gone through a bottleneck in which only spores survived, which implies that the last bacterial common ancestor was a spore
Neuroregeneration in neurodegenerative disorders
<p>Abstract</p> <p>Background</p> <p>Neuroregeneration is a relatively recent concept that includes neurogenesis, neuroplasticity, and neurorestoration - implantation of viable cells as a therapeutical approach.</p> <p>Discussion</p> <p>Neurogenesis and neuroplasticity are impaired in brains of patients suffering from Alzheimer's Disease or Parkinson's Disease and correlate with low endogenous protection, as a result of a diminished growth factors expression. However, we hypothesize that the brain possesses, at least in early and medium stages of disease, a "neuroregenerative reserve", that could be exploited by growth factors or stem cells-neurorestoration therapies.</p> <p>Summary</p> <p>In this paper we review the current data regarding all three aspects of neuroregeneration in Alzheimer's Disease and Parkinson's Disease.</p
Denial of long-term issues with agriculture on tropical peatlands will have devastating consequences
Lette
Transcriptional activity of human brain estrogen receptor-α splice variants: evidence for cell type-specific regulation
Estrogen receptor α (ERα) isoforms with complex types of alternative splicing are naturally present in the human brain and may affect canonical receptor signaling. In the present study we investigated transcriptional activity of common ERα splice variants from this group with different molecular defects: MB1 (intron retention), TADDI (small deletion between exons 3 and 4 with an insert), the Δ (deletion) 3(⁎)-7(*)/819 (complete skipping of exons 4, 5 and 6 and partial deletion of exons 3 and 7) and the Δ3-6 (lacking exons 3, 4, 5 and 6) in HeLa and M17 cells upon stimulation with (17β)estradiol or insulin-like growth factor 1 (IGF-1). In HeLa cells, all these splice variants showed the dominant negative function that was more pronounced for the TADDI. In M17 cells the dominant negative variants appeared to be the MB1 and the Δ3-6, whereas TADDI turned out to be a clearly dominant positive variant. In M17 cells mRNA levels of Δ3-6 and Δ3(*)-7(*)/819 variants increased following (17β)estradiol administration. In Hela cells (17β)estradiol up-regulated the IGF-1 receptor mRNA levels in cultures transfected with MB1, TADDI and Δ3(*)-7(*)/819. Our data demonstrate that ERα splice variants show differential levels of the transcriptional activity in a cell type-specific way and that IGF-1 signaling pathways are differentially employed in a cell-type specific manner depending on the level of the discrete ERα splice variants expressed. Functional properties of various ERα splice variants and their cell type-specificity should, thus, be considered as potential confounders of estrogen therapy effects on the brai
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