4,025 research outputs found

    A history of higher and professional correspondence education in the UK

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    Correspondence education, or learning by post, lasted over 100 years in the UK; it had its roots in the nineteenth century, peaking in the mid-1960s. It was also widespread, numbering hundreds of thousands of enrolments, significantly increasing access to higher education. Yet it has been marginalised in accounts of British higher education. This is partly because it was largely private and for-profit and so distinct from the public education system, while the state declined to play any significant role in its oversight. Consequently, little official data concerning correspondence education has ever been available. This paper constructs an account of the history of correspondence education in the UK in terms of its development as a form of academic and professional provision, and its regulatory framework. The paper also considers the reasons for the eventual demise of the correspondence education sector following changes in teaching methods, and the impact of digital technology

    Note: Modified anvil design for improved reliability in DT-Cup experiments

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    The Deformation T-Cup (DT-Cup) is a modified 6-8 multi-anvil apparatus capable of controlled strain-rate deformation experiments at pressures greater than 18 GPa. Controlled strain-rate deformation was enabled by replacing two of the eight cubic "second-stage" anvils with hexagonal cross section deformation anvils and modifying the "first-stage" wedges. However, with these modifications approximately two-thirds of experiments end with rupture of the hexagonal anvils. By replacing the hexagonal anvils with cubic anvils and, split, deformation wedge extensions, we restore the massive support to the deformation anvils that were inherent in the original multi-anvil design and prevent deformation anvil failure. With the modified parts, the DT-Cup has an experimental success rate that is similar to that of a standard hydrostatic 6-8 multi-anvil apparatus

    Phase diagram and thermal expansion of orthopyroxene-, clinopyroxene-, and ilmenite-structured MgGeO<inf>3</inf>

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    The MgGeO3 system is a low-pressure analog for the Earth-forming (Mg,Fe)SiO3 system and exhibits recoverable orthopyroxene, clinopyroxene, and ilmenite structures below 6 GPa. The pressure-temperature conditions of the clinopyroxene to ilmenite phase transition are reasonably consistent between studies, having a positive Clapeyron slope and occurring between 4 and 7 GPa in the temperature range 900-1600 K. There are, though, significant discrepancies in the Clapeyron slope of the orthopyroxene to clinopyroxene phase transition in existing works that also disagree on the stable phase at ambient conditions. The most significant factor in these differences is the method used; high-pressure experiments and thermophysical property measurements yield apparently contradicting results. Here, we perform both high pressure and temperature experiments as well as thermal expansion measurements to reconcile the measurements. High-pressure and -temperature experiments yield a Clapeyron slope of -1.0-+1.0-0.7 MPa/K for the MgGeO3 orthopyroxene-clinopyroxene phase transition, consistent with previous high-pressure and -temperature experiments. The MgGeO3 orthopyroxene-clinopyroxene-ilmenite triple point is determined to be at 0.98 GPa and 752 K, with the ilmenite phase stable at ambient conditions. The high-temperature (>600 K) thermal expansion of the clinopyroxene phase is greater than that of the other phases. Debye-Grüneisen relationships fitted to the volume-temperature data give Debye temperatures for the orthopyroxene, clinopyroxene, and ilmenite phases of 602(7), 693(10), and 758(13) K and V0 of 897.299(16), 433.192(10), and 289.156(6) Å3, respectively. The Clapeyron slopes calculated directly from the Debye-Grüneisen relationships are consistent with previous thermophysical property measurements. The presence of significant anharmonicity and/or formation of defects in the clinopyroxene phase at high-temperatures, which is not apparent in the other phases, accounts for the previous contradictions between studies. The inferred increased heat capacity of the clinopyroxene corresponds to an increase in entropy and an expanded phase field at high temperatures

    Comparing circadian dynamics in primary derived stem cells from different sources of human adult tissue

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    Optimising cell/tissue constructs so that they can be successfully accepted and integrated within a host body is essential in modern tissue engineering. To do this, adult stem cells are frequently utilised, but there are many aspects of their environment in vivo that are not completely understood. There is evidence to suggest that circadian rhythms and daily circadian temporal cues have substantial effects on stem cell activation, cell cycle, and differentiation. It was hypothesised that the circadian rhythm in human adult stem cells differs depending on the source of tissue and that different entraining signals exert differential effects depending on the anatomical source. Dexamethasone and rhythmic mechanical stretch were used to synchronise stem cells derived from the bone marrow, tooth dental pulp, and abdominal subcutaneous adipose tissue, and it was experimentally evidenced that these different stem cells differed in their circadian clock properties in response to different synchronisation mechanisms. The more primitive dental pulp-derived stem cells did not respond as well to the chemical synchronisation but showed temporal clock gene oscillations following rhythmic mechanical stretch, suggesting that incorporating temporal circadian information of different human adult stem cells will have profound implications in optimising tissue engineering approaches and stem cell therapies

    The thermal expansion of (Fe1-y Ni y )Si

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    We have measured the thermal expansion of (Fe1-y Ni y )Si for y  =  0, 0.1 and 0.2, between 40 and 1273 K. Above ~700 K the unit-cell volumes of the samples decrease approximately linearly with increasing Ni content. Below ~200 K the unit-cell volume of FeSi falls to a value between that of (Fe0.9Ni0.1)Si and (Fe0.8Ni0.2)Si. We attribute this extra contraction of the FeSi, which is a narrow band-gap semiconductor, to the depopulation of the conduction band at low temperatures; in the two alloys the additional electrons introduced by the substitution of Ni lead to the conduction band always being populated. We have fit the unit-cell volume data with a Debye internal energy model of thermal expansion and an additional volume term, above 800 K, to take account of the volumetric changes associated with changes in the composition of the sample. Using the thermophysical parameters of the fit we have estimated the band gap in FeSi to be 21(1) meV and the unit-cell volume change in FeSi associated with the depopulation of the conduction band to be 0.066(35) Å(3)/unit-cell

    Drugs-related death soon after hospital discharge among drug treatment clients in Scotland:record linkage, validation and investigation of risk factors.

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    We validate that the 28 days after hospital-discharge are high-risk for drugs-related death (DRD) among drug users in Scotland and investigate key risk-factors for DRDs soon after hospital-discharge. Using data from an anonymous linkage of hospitalisation and death records to the Scottish Drugs Misuse Database (SDMD), including over 98,000 individuals registered for drug treatment during 1 April 1996 to 31 March 2010 with 705,538 person-years, 173,107 hospital-stays, and 2,523 DRDs. Time-at-risk of DRD was categorised as: during hospitalization, within 28 days, 29-90 days, 91 days-1 year, >1 year since most recent hospital discharge versus 'never admitted'. Factors of interest were: having ever injected, misuse of alcohol, length of hospital-stay (0-1 versus 2+ days), and main discharge-diagnosis. We confirm SDMD clients' high DRD-rate soon after hospital-discharge in 2006-2010. DRD-rate in the 28 days after hospital-discharge did not vary by length of hospital-stay but was significantly higher for clients who had ever-injected versus otherwise. Three leading discharge-diagnoses accounted for only 150/290 DRDs in the 28 days after hospital-discharge, but ever-injectors for 222/290. Hospital-discharge remains a period of increased DRD-vulnerability in 2006-2010, as in 1996-2006, especially for those with a history of injecting

    Prevalence of Australians exposed to potentially cardiotoxic cancer medicines: a population-based cohort study

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    Background: Cardiovascular disease (CVD) and cancer are leading causes of death and people with cancer are at higher risk of developing CVD than the general population. Many cancer medicines have cardiotoxic effects but the size of the population exposed to these potentially cardiotoxic medicines is not known. We aimed to determine the prevalence of exposure to potentially cardiotoxic cancer medicines in Australia. Methods: We identified potentially cardiotoxic systemic cancer medicines through searching the literature and registered product information documents. We conducted a retrospective cohort study of Australians dispensed potentially cardiotoxic cancer medicines between 2005 and 2021, calculating age-standardised annual prevalence rates of people alive with exposure to a potentially cardiotoxic medicine during or prior to each year of the study period. Findings: We identified 108,175 people dispensed at least one potentially cardiotoxic cancer medicine; median age, 64 (IQR: 52–74); 57% female. Overall prevalence increased from 49 (95%CI: 48.7–49.3)/10,000 to 232 (95%CI: 231.4–232.6)/10,000 over the study period; 61 (95%CI: 60.5–61.5)/10,000 to 293 (95%CI: 292.1–293.9)/10,000 for females; and 39 (95%CI: 38.6–39.4)/10,000 to 169 (95%CI: 168.3–169.7)/10,000 for males. People alive five years following first exposure increased from 29 (95%CI: 28.8–29.2)/10,000 to 134 (95%CI: 133.6–134.4)/10,000; and from 22 (95%CI: 21.8–22.2)/10,000 to 76 (95%CI: 75.7–76.3)/10,000 for those alive at least 10 years following first exposure. Most people were exposed to only one potentially cardiotoxic medicine, rates of which increased from 39 (95%CI: 38.7–39.3)/10,000 in 2005 to 131 (95%CI: 130.6–131.4)/10,000 in 2021. Interpretation: The number of people exposed to efficacious yet potentially cardiotoxic cancer medicines in Australia is growing. Our findings can support the development of service planning and create awareness about the magnitude of cancer treatment-related cardiotoxicities. Funding: NHMRC Centre for Research Excellence in Medicines Intelligence, Cancer Institute NSW Early Career Fellowship
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