Characterization, crystallization and preliminary X-ray investigation of glyceraldehyde-3-phosphate dehydrogenase from the hyperthermophilic archaeon Sulfolobus solfataricus.

Comparative StudyJournal ArticleResearch Support, Non-U.S. Gov'tRecombinant Sulfolobus solfataricus glyceraldehyde-3-phosphate dehydrogenase has been purified and found to be a tetramer of 148 kDa. The enzyme shows dual cofactor specificity and uses NADP+ in preference to NAD+. The sequence has been compared with other GAPDH proteins including those from other archaeal sources. The purified protein has been crystallized from ammonium sulfate to produce crystals that diffract to 2.4 A with a space group of P43212 or P41212. A native data set has been collected to 2.4 A using synchrotron radiation and cryocooling.European UnionBBSR

Elective Open Suprarenal Aneurysm Repair in England from 2000 to 2010 an Observational Study of Hospital Episode Statistics

Background: Open surgery is widely used as a benchmark for the results of fenestrated endovascular repair of complex abdominal aortic aneurysms (AAA). However, the existing evidence stems from single-centre experiences, and may not be reproducible in wider practice. National outcomes provide valuable information regarding the safety of suprarenal aneurysm repair. Methods: Demographic and clinical data were extracted from English Hospital Episodes Statistics for patients undergoing elective suprarenal aneurysm repair from 1 April 2000 to 31 March 2010. Thirty-day mortality and five-year survival were analysed by logistic regression and Cox proportional hazards modeling. Results: 793 patients underwent surgery with 14% overall 30-day mortality, which did not improve over the study period. Independent predictors of 30-day mortality included age, renal disease and previous myocardial infarction. 5-year survival was independently reduced by age, renal disease, liver disease, chronic pulmonary disease, and known metastatic solid tumour. There was significant regional variation in both 30-day mortality and 5-year survival after risk-adjustment. Regional differences in outcome were eliminated in a sensitivity analysis for perioperative outcome, conducted by restricting analysis to survivors of the first 30 days after surgery. Conclusions: Elective suprarenal aneurysm repair was associated with considerable mortality and significant regional variation across England. These data provide a benchmark to assess the efficacy of complex endovascular repair of supra-renal aneurysms, though cautious interpretation is required due to the lack of information regarding aneurysm morphology. More detailed study is required, ideally through the mandatory submission of data to a national registry of suprarenal aneurysm repair

Non-BBN Constraints On The Key Cosmological Parameters

Since the baryon-to-photon ratio "eta" is in some doubt at present, we ignore the constraints on eta from big bang nucleosynthesis (BBN) and fit the three key cosmological parameters (h, Omega_M, eta) to four other observational constraints: Hubble parameter, age of the universe, cluster gas (baryon) fraction, and effective shape parameter "Gamma". We consider open and flat CDM models and flat "Lambda"-CDM models, testing goodness of fit and drawing confidence regions by the Delta-chi^2 method. CDM models with Omega_M = 1 (SCDM models) are accepted only because we allow a large error on h, permitting h < 0.5. Open CDM models are accepted only for Omega_M \gsim 0.4. Lambda-CDM models give similar results. In all of these models, large eta (\gsim 6) is favored strongly over small eta, supporting reports of low deuterium abundances on some QSO lines of sight, and suggesting that observational determinations of primordial 4He may be contaminated by systematic errors. Only if we drop the crucial Gamma constraint are much lower values of Omega_M and eta permitted.Comment: 12 pages, Kluwer Latex, 2 Postscript figures, to appear in the proceedings of the ISSI Workshop, "The Primordial Nuclei and Their Galactic Evolution" (Bern, May 6-10, 1997), ed. N. Prantzos, M. Tosi, and R. von Steiger (Kluwer, Dordrecht

Real-time massive convolution for audio applications on GPU

[EN] Massive convolution is the basic operation in multichannel acoustic signal processing. This field has experienced a major development in recent years. One reason for this has been the increase in the number of sound sources used in playback applications available to users. Another reason is the growing need to incorporate new effects and to improve the hearing experience. Massive convolution requires high computing capacity. GPUs offer the possibility of parallelizing these operations. This allows us to obtain the processing result in much shorter time and to free up CPU resources. One important aspect lies in the possibility of overlapping the transfer of data from CPU to GPU and vice versa with the computation, in order to carry out real-time applications. Thus, a synthesis of 3D sound scenes could be achieved with only a peer-to-peer music streaming environment using a simple GPU in your computer, while the CPU in the computer is being used for other tasks. Nowadays, these effects are obtained in theaters or funfairs at a very high cost, requiring a large quantity of resources. Thus, our work focuses on two mains points: to describe an efficient massive convolution implementation and to incorporate this task to real-time multichannel-sound applications. © 2011 Springer Science+Business Media, LLC.This work was partially supported by the Spanish Ministerio de Ciencia e Innovacion (Projects TIN2008-06570-C04-02 and TEC2009-13741), Universidad Politecnica de Valencia through PAID-05-09 and Generalitat Valenciana through project PROMETEO/2009/2013Belloch Rodríguez, JA.; Gonzalez, A.; Martínez Zaldívar, FJ.; Vidal Maciá, AM. (2011). Real-time massive convolution for audio applications on GPU. Journal of Supercomputing. 58(3):449-457. https://doi.org/10.1007/s11227-011-0610-8S449457583Spors S, Rabenstein R, Herbordt W (2007) Active listening room compensation for massive multichannel sound reproduction system using wave-domain adaptive filtering. J Acoust Soc Am 122:354–369Huang Y, Benesty J, Chen J (2008) Generalized crosstalk cancellation and equalization using multiple loudspeakers for 3D sound reproduction at the ears of multiple listeners. In: IEEE int conference on acoustics, speech and signal processing, Las Vegas, USA, pp 405–408Cowan B, Kapralos B (2008) Spatial sound for video games and virtual environments utilizing real-time GPU-based convolution. In: Proceedings of the ACM FuturePlay 2008 international conference on the future of game design and technology, Toronto, Ontario, Canada, November 3–5Belloch JA, Vidal AM, Martinez-Zaldivar FJ, Gonzalez A (2010) Multichannel acoustic signal processing on GPU. In: Proceedings of the 10th international conference on computational and mathematical methods in science and engineering, vol 1. Almeria, Spain, June 26–30, pp 181–187Cowan B, Kapralos B (2009) GPU-based one-dimensional convolution for real-time spatial sound generation. Sch J 3(5)Soliman SS, Mandyam DS, Srinath MD (1997) Continuous and discrete signals and systems. Prentice Hall, New YorkOppenheim AV, Willsky AS, Hamid Nawab S (1996) Signals and systems. Prentice Hall, New YorkopenGL: http://www.opengl.org/MKL library: http://software.intel.com/en-us/intel-mkl/MKL library: http://software.intel.com/en-us/intel-ipp/CUFFT library: http://developer.download.nvidia.com/compute/cuda/3_1/toolkit/docs/CUFFT_Library_3.1.pdfCUDA Toolkit 3.1: http://developer.nvidia.com/object/cuda_3_1_downloads.htmlCUDA Toolkit 3.2: http://developer.nvidia.com/object/cuda_3_1_downloads.htmlDatasheet of AC’97 SoundMAX Codec: http://www.xilinx.com/products/boards/ml505/datasheets/87560554AD1981B_c.pd

Searching for serial refreshing in working memory:Using response times to track the content of the focus of attention over time

One popular idea is that, to support maintenance of a set of elements over brief periods of time, the focus of attention rotates among the different elements thereby serially refreshing the content of Working Memory (WM). In the research reported here, probe letters were presented between to-be-remembered letters. Response times to these probes were used to infer the status of the different items in WM. If the focus of attention cycles from one item to the next, its content should be different at different points in time and this should be reflected in a change in the response time patterns over time. Across a set of four experiments, we demonstrate a striking pattern of invariance in the response time patterns over time, suggesting that either the content of the focus of attention did not change over time or that response times cannot be used to infer the content of the focus of attention. We discuss how this pattern constrains models of WM, attention, and human information processing

Doppler broadening of in-flight positron annihilation radiation due to electron momentum

An overview is given on the first observation of Doppler broadening due to electron momentum in the τ rays emitted from in-flight two-photon annihilation when highly energetic positrons traverse thin foils. This observation can serve as basis in the development of a new probe of electron momentum distributions similar to Compton or electron scattering technique

A computational study on altered theta-gamma coupling during learning and phase coding

There is considerable interest in the role of coupling between theta and gamma oscillations in the brain in the context of learning and memory. Here we have used a neural network model which is capable of producing coupling of theta phase to gamma amplitude firstly to explore its ability to reproduce reported learning changes and secondly to memory-span and phase coding effects. The spiking neural network incorporates two kinetically different GABAA receptor-mediated currents to generate both theta and gamma rhythms and we have found that by selective alteration of both NMDA receptors and GABAA,slow receptors it can reproduce learning-related changes in the strength of coupling between theta and gamma either with or without coincident changes in theta amplitude. When the model was used to explore the relationship between theta and gamma oscillations, working memory capacity and phase coding it showed that the potential storage capacity of short term memories, in terms of nested gamma-subcycles, coincides with the maximal theta power. Increasing theta power is also related to the precision of theta phase which functions as a potential timing clock for neuronal firing in the cortex or hippocampus

Differential cargo mobilisation within Weibel-Palade bodies after transient fusion with the plasma membrane.

Inflammatory chemokines can be selectively released from Weibel-Palade bodies (WPBs) during kiss-and-run exocytosis. Such selectivity may arise from molecular size filtering by the fusion pore, however differential intra-WPB cargo re-mobilisation following fusion-induced structural changes within the WPB may also contribute to this process. To determine whether WPB cargo molecules are differentially re-mobilised, we applied FRAP to residual post-fusion WPB structures formed after transient exocytosis in which some or all of the fluorescent cargo was retained. Transient fusion resulted in WPB collapse from a rod to a spheroid shape accompanied by substantial swelling (>2 times by surface area) and membrane mixing between the WPB and plasma membranes. Post-fusion WPBs supported cumulative WPB exocytosis. To quantify diffusion inside rounded organelles we developed a method of FRAP analysis based on image moments. FRAP analysis showed that von Willebrand factor-EGFP (VWF-EGFP) and the VWF-propolypeptide-EGFP (Pro-EGFP) were immobile in post-fusion WPBs. Because Eotaxin-3-EGFP and ssEGFP (small soluble cargo proteins) were largely depleted from post-fusion WPBs, we studied these molecules in cells preincubated in the weak base NH4Cl which caused WPB alkalinisation and rounding similar to that produced by plasma membrane fusion. In these cells we found a dramatic increase in mobilities of Eotaxin-3-EGFP and ssEGFP that exceeded the resolution of our method (∼ 2.4 µm2/s mean). In contrast, the membrane mobilities of EGFP-CD63 and EGFP-Rab27A in post-fusion WPBs were unchanged, while P-selectin-EGFP acquired mobility. Our data suggest that selective re-mobilisation of chemokines during transient fusion contributes to selective chemokine secretion during transient WPB exocytosis. Selective secretion provides a mechanism to regulate intravascular inflammatory processes with reduced risk of thrombosis

A novel malaria vaccine candidate antigen expressed in Tetrahymena thermophila

Development of effective malaria vaccines is hampered by the problem of producing correctly folded Plasmodium proteins for use as vaccine components. We have investigated the use of a novel ciliate expression system, Tetrahymena thermophila, as a P. falciparum vaccine antigen platform. A synthetic vaccine antigen composed of N-terminal and C-terminal regions of merozoite surface protein-1 (MSP-1) was expressed in Tetrahymena thermophila. The recombinant antigen was secreted into the culture medium and purified by monoclonal antibody (mAb) affinity chromatography. The vaccine was immunogenic in MF1 mice, eliciting high antibody titers against both N- and C-terminal components. Sera from immunized animals reacted strongly with P. falciparum parasites from three antigenically different strains by immunofluorescence assays, confirming that the antibodies produced are able to recognize parasite antigens in their native form. Epitope mapping of serum reactivity with a peptide library derived from all three MSP-1 Block 2 serotypes confirmed that the MSP-1 Block 2 hybrid component of the vaccine had effectively targeted all three serotypes of this polymorphic region of MSP-1. This study has successfully demonstrated the use of Tetrahymena thermophila as a recombinant protein expression platform for the production of malaria vaccine antigens