803 research outputs found

    The anodic oxidation of maleic acid

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    The purpose of this investigation was to determine the mechanism of the anodic oxidation of maleic acid on platinized-platinum electrodes at 80⁰C. Current density-potential studies were conducted varying the parameters of maleic acid concentration and pH. The faradaic efficiency of the oxidation of maleic acid to yield CO₂ was determined. The effect of temperature on current density was also studied to determine the activation energy for the reaction. The oxidation of maleic acid occurred only in acidic solutions. The faradaic efficiency was found to be approximately 97 ± 5 per cent. A linear Tafel region was found which had a slope of 145 - 170 millivolts ~ 2.3RT/aF). The rate decreased with increasing maleic acid concentration. There was very little, if any, effect of pH on the rate in the range 0.3 to 2.0. At pH\u27s greater than 2.0, the rate increased rapidly. The activation energy was 33.4 kilocalories at the reversible potential.... --Abstract

    Political trials and the suppression of popular radicalism in England, 1799-1820

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    This chapter examines the decision-making process between the Home Office and the government’s law officers in prosecuting individuals for sedition and treason in the period 1799–1820. The term state trial suggests a more centralised and government-led repression of popular radicalism than the process was in practice. Provincial reformers also faced the complex layers of their local justice system, which was more loyalist, committed to stamping out political radicalism. The trial of the “Thirty Eight” Manchester radicals in June 1812 demonstrates the mutable definitions of treason, sedition and processes of justice in the theatre of the court.Peer reviewe

    Three-dimensional modeling of the human eye based on magnetic resonance imaging

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    PURPOSE. A methodology for noninvasively characterizing the three-dimensional (3-D) shape of the complete human eye is not currently available for research into ocular diseases that have a structural substrate, such as myopia. A novel application of a magnetic resonance imaging (MRI) acquisition and analysis technique is presented that, for the first time, allows the 3-D shape of the eye to be investigated fully. METHODS. The technique involves the acquisition of a T2-weighted MRI, which is optimized to reveal the fluid-filled chambers of the eye. Automatic segmentation and meshing algorithms generate a 3-D surface model, which can be shaded with morphologic parameters such as distance from the posterior corneal pole and deviation from sphericity. Full details of the method are illustrated with data from 14 eyes of seven individuals. The spatial accuracy of the calculated models is demonstrated by comparing the MRI-derived axial lengths with values measured in the same eyes using interferometry. RESULTS. The color-coded eye models showed substantial variation in the absolute size of the 14 eyes. Variations in the sphericity of the eyes were also evident, with some appearing approximately spherical whereas others were clearly oblate and one was slightly prolate. Nasal-temporal asymmetries were noted in some subjects. CONCLUSIONS. The MRI acquisition and analysis technique allows a novel way of examining 3-D ocular shape. The ability to stratify and analyze eye shape, ocular volume, and sphericity will further extend the understanding of which specific biometric parameters predispose emmetropic children subsequently to develop myopia. Copyright © Association for Research in Vision and Ophthalmology

    Using public engagement and consultation to inform the development of ageing-and dementia-friendly pharmacies – Innovative practice

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    This study explored public perceptions about the importance of, and how to create, ageing- and dementia-friendly pharmacists and pharmacies. In September 2016, four focus groups (45 minutes each) were conducted with 16 participants who represented organisations, groups or forums working with and/or for older people and people with dementia in Greater London. Discussions were recorded via handwritten notes and thematically analysed. Participants confirmed the importance of pharmacists and pharmacies being ageing- and dementia-friendly and described variability in whether this is currently the case. Suggested strategies for improvement included targeting communication, pharmacist leadership and shop layout

    In vivo measures of anterior scleral resistance in humans with rebound tonometry

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    Purpose: To measure regional variations in anterior scleral resistance (ASR) using a ballistic rebound tonometer (RBT) and examine whether the variations are significantly affected by ethnicity and refractive error (RE). Methods: ASR was measured using a RBT (iCare TA01) following calibration against the biomechanical properties of agarose biogels. Eight scleral regions (nasal, temporal, superior, inferior, inferior-nasal, inferior-temporal, superior-nasal and superior-temporal) were measured at locations 4mm from the limbus. Subjects were 130 young adults comprising three ethnic groups whose RE distributions [MSE (D) ± S.D.] incorporated individuals categorised as without-myopia (NM; MSE ≄ −0.50) and with-myopia (WM; MSE < −0.50); British-White (BW): 26 NM + 0.52 ± 1.15D; 22 WM −3.83 ± 2.89D]; British-South-Asian (BSA): [9 NM + 0.49 ± 1.06D; 11 WM −5.07 ± 3.76D; Hong-Kong-Chinese (HKC): [11 NM + 0.39 ± 0.66D; 49 WM −4.46 ± 2.70D]. Biometric data were compiled using cycloplegic open-field autorefraction and the Zeiss IOLMaster. Two- and three-way repeated measures analysis of variances (anovas) tested regional differences for RBT values across both refractive status and ethnicity whilst stepwise forward multiple linear regression was used as an exploratory test. Results: Significant regional variations in ASR were identified for the BW, BSA and HKC (p < 0.001) individuals; superior-temporal region showed the lowest levels of resistance whilst the inferior-nasal region the highest. Compared to the BW and BSA groups, the HKC subjects displayed a significant increase in mean resistance for each respective region (p < 0.001). With the exception of the inferior region, ethnicity was found to be the chief predictor for variation in the scleral RBT values for all other regions. Mean RE group differences were insignificant. Conclusions: The novel application of RBT to the anterior sclera confirm regional variation in ASR. Greater ASR amongst the HKC group than the BW and BSA individuals suggests that ethnic differences in anterior scleral biomechanics may exist

    Oakleaf: an S locus-linked mutation of Primula vulgaris that affects leaf and flower development

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    ‱In Primula vulgaris outcrossing is promoted through reciprocal herkogamy with insect-mediated cross-pollination between pin and thrum form flowers. Development of heteromorphic flowers is coordinated by genes at the S locus. To underpin construction of a genetic map facilitating isolation of these S locus genes, we have characterised Oakleaf, a novel S locus-linked mutant phenotype. ‱We combine phenotypic observation of flower and leaf development, with classical genetic analysis and next-generation sequencing to address the molecular basis of Oakleaf. ‱Oakleaf is a dominant mutation that affects both leaf and flower development; plants produce distinctive lobed leaves, with occasional ectopic meristems on the veins. This phenotype is reminiscent of overexpression of Class I KNOX-homeodomain transcription factors. We describe the structure and expression of all eight P. vulgaris PvKNOX genes in both wild-type and Oakleaf plants, and present comparative transcriptome analysis of leaves and flowers from Oakleaf and wild-type plants. ‱Oakleaf provides a new phenotypic marker for genetic analysis of the Primula S locus. We show that none of the Class I PvKNOX genes are strongly upregulated in Oakleaf leaves and flowers, and identify cohorts of 507 upregulated and 314 downregulated genes in the Oakleaf mutant

    Quantitation of drug sensitivity by human metastatic melanoma colony-forming units.

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    We measured the effect of 6 standard (Adriamycin, BCNU, DTIC, melphalan, vinblastine, actinomycin D) and 3 Phase II agents (cis-platinum, vindesine, AMSA) on melanoma colony-forming units (CFU) in soft agar from biopsies of 50 patients with metastatic melanoma. Melanoma CFU demonstrated marked heterogeneity in chemosensitivity to these 9 drugs. Reduction in survival of CFU below 38% at one-tenth the pharmacologically achievable 1h concentration (our operational definition of chemosensitivity) was obtained in only 19% of 200 in vitro trials, and was usually the same whether or not patients had been exposed to prior chemotherapy, suggesting that melanoma CFU are inherently resistant to presently available chemotherapeutic drugs. The soft-agar assay was 86% accurate (25/29 cases) in identifying drugs to which the tumour was resistant in vivo, and 63% accurate (12/19 trials) in identifying drugs to which the tumour was clinically sensitive, counting mixed responses as responses. In contrast, if mixed responses were classified as progressive disease, the accuracy of identification of sensitivity fell to 42% (8/19 trials). These investigations furnish a quantitative description of the chemosensitivity of human metastatic melanoma CFU. Additionally, these studies serve as a useful step towards the development of an in vitro chemosensitivity test for human melanoma, and provide an operational quantitative basis for further exploration of in vitro-directed therapy in metastatic neoplasms

    Older people's priorities in health and social care research and practice: a public engagement workshop

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    As the world’s population ages, there is an increasing need for research that addresses the priorities of older people. A public engagement workshop focusing on the priorities of older people for research and practice in health and social care was attended by seventy-five people aged 70 years and above in London, United Kingdom (UK). The workshop aimed to identify and prioritise issues important to older people that would benefit from further research and act as a platform to promote sharing of ideas and problems related to these important issues. Key priorities emerged including loneliness and isolation, support and training for professional and family carers, post-surgical care, negative perceptions of older people and inequalities related to public services and healthcare. Participants further suggested older people should be actively involved in all stages of the research process

    Effect of Vorapaxar Alone and in Combination with Aspirin on Bleeding Time and Platelet Aggregation in Healthy Adult Subjects.

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    The effect of the protease-activated receptor-1 (PAR-1) antagonist vorapaxar on human bleeding time is not known. This was a randomized, two-period, open-label trial in healthy men (n = 31) and women (n = 5). In period 1, subjects received 81 mg aspirin q.d. or a vorapaxar regimen achieving steady-state plasma concentrations equivalent to chronic 2.5 mg q.d. doses, for 7 days. In period 2, each group added 7 days of the therapy alternate to that of period 1 without washout. Bleeding time and platelet aggregation using arachidonic acid, ADP, and TRAP agonists were assessed. Bleeding time geometric mean ratio (90% CI) for vorapaxar/baseline was 1.01 (0.88-1.15), aspirin/baseline was 1.32 (1.15-1.51), vorapaxar + aspirin/vorapaxar was 1.47 (1.26-1.70), and vorapaxar + aspirin/aspirin was 1.12 (0.96-1.30). Unlike aspirin, vorapaxar did not prolong bleeding time compared with baseline. Bleeding time following administration of vorapaxar with aspirin was similar to that following aspirin alone
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