1,139 research outputs found

    Numeracy for 14 to 19-year-olds

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    GCSE results and international comparisons show that performance in numeracy is lower in Wales than that in the other home nations and below the average for OECD countries. Standards of numeracy as judged in school inspections are also lower than for communication in English and information and communication technology. The number of learners in schools, colleges and work-based learning providers who gain application of number qualifications has increased substantially over the last five years. However, too many of these learners gain qualifications at too low a level relative to their ability. These learners do not improve their numeracy skills by taking qualifications at too low a level. Only a minority of schools plan to develop numeracy systematically across the curriculum. Only a few schools track the progress of pupils in numeracy well enough, including the pupils who previously received support for numeracy in key stage 3. Around a half of the schools surveyed do not provide specific support for learners with poor numeracy skills in key stage 4. Although schools assess pupils’ numeracy skills, they do not share this information well enough when their learners attend courses at college or other providers. Further education colleges and work-based learning providers assess the level of learners’ numeracy skills at the start of courses. They generally use this information well to identify whether learners need basic support. As a result, many learners have individual learning plans and benefit from a range of support strategies. However, providers often enter learners for key skills qualifications only at the level needed to complete their framework qualification aim and do not challenge learners to achieve beyond this level

    Shape-enforcing operators for point and interval estimators

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    https://arxiv.org/abs/1809.01038https://arxiv.org/abs/1809.01038First author draf

    Dissolved Organic Carbon from the Upper Rio Negro Protects Zebrafish (Danio rerio) Against Ionoregulatory Disturbances Caused by Low pH Exposure

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    The so-called “blackwaters” of the Amazonian Rio Negro are rich in highly coloured dissolved organic carbon (DOC), but ion-poor and very acidic, conditions that would cause fatal ionoregulatory failure in most fish. However these blackwaters support 8% of the world’s ichthyofauna. We tested the hypothesis that native DOC provides protection against ionoregulatory dysfunction in this extreme environment. DOCs were isolated by reverse-osmosis from two Rio Negro sites. Physico-chemical characterization clearly indicated a terrigenous origin, with a high proportion of hydroxyl and phenolic sites, high chemical reactivity to protons, and unusual proteinaceous fluorescence. When tested using zebrafish (a model organism), Rio Negro DOC provided almost perfect protection against ionoregulatory disturbances associated with acute exposure to pH 4.0 in ion-poor water. DOC reduced diffusive losses of Na+ and Cl−, and promoted a remarkable stimulation of Na+ uptake that otherwise would have been completely inhibited. Additionally, prior acclimation to DOC at neutral pH reduced rates of branchial Na+ turnover, and provided similar protection against acid-induced ionoregulatory disturbances, even if the DOC was no longer present. These results reinforce the important roles that DOC molecules can play in the regulation of gill functions in freshwater fish, particularly in ion-poor, acidic blackwaters

    Gradients of glucose metabolism regulate morphogen signalling required for specifying tonotopic organisation in the chicken cochlea

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    In vertebrates with elongated auditory organs, mechanosensory hair cells (HCs) are organised such that complex sounds are broken down into their component frequencies along a proximal-to-distal long (tonotopic) axis. Acquisition of unique morphologies at the appropriate position along the chick cochlea, the basilar papilla, requires that nascent HCs determine their tonotopic positions during development. The complex signalling within the auditory organ between a developing HC and its local niche along the cochlea is poorly understood. Using a combination of live imaging and NAD(P)H fluorescence lifetime imaging microscopy, we reveal that there is a gradient in the cellular balance between glycolysis and the pentose phosphate pathway in developing HCs along the tonotopic axis. Perturbing this balance by inhibiting different branches of cytosolic glucose catabolism disrupts developmental morphogen signalling and abolishes the normal tonotopic gradient in HC morphology. These findings highlight a causal link between graded morphogen signalling and metabolic reprogramming in specifying the tonotopic identity of developing HCs

    The health and socioeconomic impacts of major multi-sport events: systematic review (1978-2008)

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    Objective To assess the effects of major multi-sport events on health and socioeconomic determinants of health in the population of the city hosting the event

    Wind-accretion disks in wide binaries, second generation protoplanetary disks and accretion onto white dwarfs

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    Mass transfer from an evolved donor star to its binary companion is a standard feature of stellar evolution in binaries. In wide binaries, the companion star captures some of the mass ejected in a wind by the primary star. The captured material forms an accretion disk. Here, we study the evolution of wind-accretion disks, using a numerical approach which allows us to follow the long term evolution. For a broad range of initial conditions, we derive the radial density and temperature profiles of the disk. In most cases, wind-accretion leads to long-lived stable disks over the lifetime of the AGB donor star. The disks have masses of a few times 10^{-5}-10^{-3} M_sun, with surface density and temperature profiles that follow broken power-laws. The total mass in the disk scales approximately linearly with the viscosity parameter used. Roughly 50% to 80% of the mass falling into the disk accretes onto the central star; the rest flows out through the outer edge of the disk into the stellar wind of the primary. For systems with large accretion rates, the secondary accretes as much as 0.1 M_sun. When the secondary is a white dwarf, accretion naturally leads to nova and supernova eruptions. For all types of secondary star, the surface density and temperature profiles of massive disks resemble structures observed in protoplanetary disks, suggesting that coordinated observational programs might improve our understanding of uncertain disk physics.Comment: ApJ, in press. Some discussion on thermal instabilities, and different viscosities adde

    Anoxia- and hypoxia-induced expression of LDH-A* in the Amazon Oscar, Astronotus crassipinis

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    Adaptation or acclimation to hypoxia occurs via the modulation of physiologically relevant genes, such as erythropoietin, transferrin, vascular endothelial growth factor, phosphofructokinase and lactate dehydrogenase A. In the present study, we have cloned, sequenced and examined the modulation of the LDH-A gene after an Amazonian fish species, Astronotus crassipinis (the Oscar), was exposed to hypoxia and anoxia. In earlier studies, we have discovered that adults of this species are extremely tolerant to hypoxia and anoxia, while the juveniles are less tolerant. Exposure of juveniles to acute hypoxia and anoxia resulted in increased LDH-A gene expression in skeletal and cardiac muscles. When exposed to graded hypoxia juveniles show decreased LDH-A expression. In adults, the levels of LDH-A mRNA did not increase in hypoxic or anoxic conditions. Our results demonstrate that, when given time for acclimation, fish at different life-stages are able to respond differently to survive hypoxic episodes

    Prostate cancer-specific PET radiotracers : a review on the clinical utility in recurrent disease

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    Prostate cancer-specific positron emission tomography (pcPET) has been shown to detect sites of disease recurrence at serum prostate-specific antigen (PSA) levels that are lower than those levels detected by conventional imaging. Commonly used pcPET radiotracers in the setting of biochemical recurrence are reviewed including carbon 11/fludeoxyglucose 18 (F-18) choline, gallium 68/F-18 prostate-specificmembrane antigen (PSMA), and F-18 fluciclovine. Review of the literature generally favors PSMA-based agents for the detection of recurrence as a function of low PSA levels. Positive gallium 68/F-18PSMA positron emission tomography/computed tomography scans detected potential sites of recurrence in a median 51.5% of patients when PSA level is 2.0 ng/mL. Review of carbon 11/fludeoxyglucose 18 (F-18) choline and F-18 fluciclovine data commonly demonstrated lower detection rates for each respective PSA cohort, although with some important caveats, despite having similar operational characteristics to PSMA-based imaging. Sensitive pcPET imaging has provided new insight into the early patterns of disease spread, which has prompted judicious reconsideration of additional local therapy after either prostatectomy, definitive radiation therapy, or postprostatectomy radiation therapy. This review discusses the literature, clinical utility, availability, and fundamental understanding of pcPET imaging needed to improve clinical practice. (C) 2017 The Authors. Published by Elsevier Inc. on behalf of American Society for Radiation Oncology