165 research outputs found

    Secondary flows and losses in gas turbines.

    Get PDF
    2 volsAvailable from British Library Document Supply Centre- DSC:D67794/86 / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo

    Newcastle upon Tyne, the Eye of the North

    Get PDF
    Newcastle upon Tyne is one of England’s great cities. Many think of it mainly as a product of the Industrial Revolution when abundant resources of coal, iron ore and water came together to create a Victorian industrial powerhouse. In fact, Newcastle’s long and proud history began in Roman times when Hadrian’s Wall marked the northernmost point of the Roman Empire.Newcastle became a thriving medieval port, with trading connections around the North Sea, the Atlantic, the Baltic countries and the Mediterranean. By the mid-17th century, Newcastle was not only a major European port, but was also becoming the pre-eminent exporter of coal fuelling the incipient industrial revolution. This volume brings together the archaeological evidence for occupation in the historic core of Newcastle between the prehistoric period and 1650. It places the evidence in the context of the evolving historical communities who made and occupied the site, and in the wider context of medieval and early modern European urban life.The volume synthesizes archaeological and historical evidence, highlighting material only known through excavation – like the early medieval use of the decaying Roman fort for a cemetery and probable church – as well as throwing new light on documented activities – like the way in which the waterfront was physically extended and consolidated to support trade from the 12th century onwards. Taking its name from a castle of national significance, planted after the Norman Conquest as a bulwark against Northern rebels and Scottish aggression, Newcastle was established as the king’s ‘Eye of the North’

    Newcastle upon Tyne, the Eye of the North

    Get PDF
    Newcastle upon Tyne is one of England’s great cities. Many think of it mainly as a product of the Industrial Revolution when abundant resources of coal, iron ore and water came together to create a Victorian industrial powerhouse. In fact, Newcastle’s long and proud history began in Roman times when Hadrian’s Wall marked the northernmost point of the Roman Empire.Newcastle became a thriving medieval port, with trading connections around the North Sea, the Atlantic, the Baltic countries and the Mediterranean. By the mid-17th century, Newcastle was not only a major European port, but was also becoming the pre-eminent exporter of coal fuelling the incipient industrial revolution. This volume brings together the archaeological evidence for occupation in the historic core of Newcastle between the prehistoric period and 1650. It places the evidence in the context of the evolving historical communities who made and occupied the site, and in the wider context of medieval and early modern European urban life.The volume synthesizes archaeological and historical evidence, highlighting material only known through excavation – like the early medieval use of the decaying Roman fort for a cemetery and probable church – as well as throwing new light on documented activities – like the way in which the waterfront was physically extended and consolidated to support trade from the 12th century onwards. Taking its name from a castle of national significance, planted after the Norman Conquest as a bulwark against Northern rebels and Scottish aggression, Newcastle was established as the king’s ‘Eye of the North’

    C9ORF72-derived poly-GA DPRs undergo endocytic uptake in iAstrocytes and spread to motor neurons

    Get PDF
    Dipeptide repeat (DPR) proteins are aggregation-prone polypeptides encoded by the pathogenic GGGGCC repeat expansion in the C9ORF72 gene, the most common genetic cause of amyotrophic lateral sclerosis and frontotemporal dementia. In this study, we focus on the role of poly-GA DPRs in disease spread. We demonstrate that recombinant poly-GA oligomers can directly convert into solid-like aggregates and form characteristic β-sheet fibrils in vitro. To dissect the process of cell-to-cell DPR transmission, we closely follow the fate of poly-GA DPRs in either their oligomeric or fibrillized form after administration in the cell culture medium. We observe that poly-GA DPRs are taken up via dynamin-dependent and -independent endocytosis, eventually converging at the lysosomal compartment and leading to axonal swellings in neurons. We then use a co-culture system to demonstrate astrocyte-to-motor neuron DPR propagation, showing that astrocytes may internalise and release aberrant peptides in disease pathogenesis. Overall, our results shed light on the mechanisms of poly-GA cellular uptake and propagation, suggesting lysosomal impairment as a possible feature underlying the cellular pathogenicity of these DPR species

    On the mechanisms governing gas penetration into a tokamak plasma during a massive gas injection

    Get PDF
    A new 1D radial fluid code, IMAGINE, is used to simulate the penetration of gas into a tokamak plasma during a massive gas injection (MGI). The main result is that the gas is in general strongly braked as it reaches the plasma, due to mechanisms related to charge exchange and (to a smaller extent) recombination. As a result, only a fraction of the gas penetrates into the plasma. Also, a shock wave is created in the gas which propagates away from the plasma, braking and compressing the incoming gas. Simulation results are quantitatively consistent, at least in terms of orders of magnitude, with experimental data for a D 2 MGI into a JET Ohmic plasma. Simulations of MGI into the background plasma surrounding a runaway electron beam show that if the background electron density is too high, the gas may not penetrate, suggesting a possible explanation for the recent results of Reux et al in JET (2015 Nucl. Fusion 55 093013)

    Velocity-space sensitivity of the time-of-flight neutron spectrometer at JET

    Get PDF
    The velocity-space sensitivities of fast-ion diagnostics are often described by so-called weight functions. Recently, we formulated weight functions showing the velocity-space sensitivity of the often dominant beam-target part of neutron energy spectra. These weight functions for neutron emission spectrometry (NES) are independent of the particular NES diagnostic. Here we apply these NES weight functions to the time-of-flight spectrometer TOFOR at JET. By taking the instrumental response function of TOFOR into account, we calculate time-of-flight NES weight functions that enable us to directly determine the velocity-space sensitivity of a given part of a measured time-of-flight spectrum from TOFOR

    Relationship of edge localized mode burst times with divertor flux loop signal phase in JET

    Get PDF
    A phase relationship is identified between sequential edge localized modes (ELMs) occurrence times in a set of H-mode tokamak plasmas to the voltage measured in full flux azimuthal loops in the divertor region. We focus on plasmas in the Joint European Torus where a steady H-mode is sustained over several seconds, during which ELMs are observed in the Be II emission at the divertor. The ELMs analysed arise from intrinsic ELMing, in that there is no deliberate intent to control the ELMing process by external means. We use ELM timings derived from the Be II signal to perform direct time domain analysis of the full flux loop VLD2 and VLD3 signals, which provide a high cadence global measurement proportional to the voltage induced by changes in poloidal magnetic flux. Specifically, we examine how the time interval between pairs of successive ELMs is linked to the time-evolving phase of the full flux loop signals. Each ELM produces a clear early pulse in the full flux loop signals, whose peak time is used to condition our analysis. The arrival time of the following ELM, relative to this pulse, is found to fall into one of two categories: (i) prompt ELMs, which are directly paced by the initial response seen in the flux loop signals; and (ii) all other ELMs, which occur after the initial response of the full flux loop signals has decayed in amplitude. The times at which ELMs in category (ii) occur, relative to the first ELM of the pair, are clustered at times when the instantaneous phase of the full flux loop signal is close to its value at the time of the first ELM

    The western painted turtle genome, a model for the evolution of extreme physiological adaptations in a slowly evolving lineage

    Get PDF
    Background: We describe the genome of the western painted turtle, Chrysemys picta bellii, one of the most widespread, abundant, and well-studied turtles. We place the genome into a comparative evolutionary context, and focus on genomic features associated with tooth loss, immune function, longevity, sex differentiation and determination, and the species' physiological capacities to withstand extreme anoxia and tissue freezing.Results: Our phylogenetic analyses confirm that turtles are the sister group to living archosaurs, and demonstrate an extraordinarily slow rate of sequence evolution in the painted turtle. The ability of the painted turtle to withstand complete anoxia and partial freezing appears to be associated with common vertebrate gene networks, and we identify candidate genes for future functional analyses. Tooth loss shares a common pattern of pseudogenization and degradation of tooth-specific genes with birds, although the rate of accumulation of mutations is much slower in the painted turtle. Genes associated with sex differentiation generally reflect phylogeny rather than convergence in sex determination functionality. Among gene families that demonstrate exceptional expansions or show signatures of strong natural selection, immune function and musculoskeletal patterning genes are consistently over-represented.Conclusions: Our comparative genomic analyses indicate that common vertebrate regulatory networks, some of which have analogs in human diseases, are often involved in the western painted turtle's extraordinary physiological capacities. As these regulatory pathways are analyzed at the functional level, the painted turtle may offer important insights into the management of a number of human health disorders
    • …
    corecore