4,230 research outputs found

    A Population-Based Ultra-Widefield Digital Image Grading Study for Age-Related Macular Degeneration-Like Lesions at the Peripheral Retina.

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    Our understanding of the relevance of peripheral retinal abnormalities to disease in general and in age-related macular degeneration (AMD) in particular is limited by the lack of detailed peripheral imaging studies. The purpose of this study was to develop image grading protocols suited to ultra-widefield imaging (UWFI) in an aged population

    Role of advanced technology in the detection of sight-threatening eye disease in a UK community setting.

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    Background/aims: To determine the performance of combinations of structural and functional screening tests in detecting sight-threatening eye disease in a cohort of elderly subjects recruited from primary care. Methods: 505 subjects aged ≥60 years underwent frequency doubling technology (FDT) perimetry, iVue optical coherence tomography (iWellness and peripapillary retinal nerve fibre layer (RNFL) scans) and intraocular pressure with the Ocular Response Analyzer, all performed by an ophthalmic technician. The reference standard was a full ophthalmic examination by an experienced clinician who was masked to the index test results. Subjects were classified as presence or absence of sight-threatening eye disease (clinically significant cataract, primary open-angle glaucoma, intermediate or advanced age-related macular degeneration and significant diabetic retinopathy). Univariate and multivariate logistic regression analyses were used to determine the association between abnormal screening test results and the presence of sight-threatening eye disease. Results: 171 subjects (33.8%) had one or more sight-threatening eye diseases. The multivariate analysis found significant associations with any of the target conditions for visual acuity of <6/12, an abnormal FDT and peripapillary RNFL thickness outside the 99% normal limit. The sensitivity of this optimised screening panel was 61.3% (95% CI 53.5 to 68.7), with a specificity of 78.8% (95% CI 74.0 to 83.1), a positive predictive value of 59.5% (95% CI 53.7 to 65.2) and an overall diagnostic accuracy of 72.9% (95% CI 68.8 to 76.8). Conclusions: A subset of screening tests may provide an accurate and efficient means of population screening for significant eye disease in the elderly. This study provides useful preliminary data to inform the development of further larger, multicentre screening studies to validate this screening panel

    Pleural mesothelioma and lung cancer risks in relation to occupational history and asbestos lung burden.

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    BACKGROUND: We have conducted a population-based study of pleural mesothelioma patients with occupational histories and measured asbestos lung burdens in occupationally exposed workers and in the general population. The relationship between lung burden and risk, particularly at environmental exposure levels, will enable future mesothelioma rates in people born after 1965 who never installed asbestos to be predicted from their asbestos lung burdens. METHODS: Following personal interview asbestos fibres longer than 5 µm were counted by transmission electron microscopy in lung samples obtained from 133 patients with mesothelioma and 262 patients with lung cancer. ORs for mesothelioma were converted to lifetime risks. RESULTS: Lifetime mesothelioma risk is approximately 0.02% per 1000 amphibole fibres per gram of dry lung tissue over a more than 100-fold range, from 1 to 4 in the most heavily exposed building workers to less than 1 in 500 in most of the population. The asbestos fibres counted were amosite (75%), crocidolite (18%), other amphiboles (5%) and chrysotile (2%). CONCLUSIONS: The approximate linearity of the dose-response together with lung burden measurements in younger people will provide reasonably reliable predictions of future mesothelioma rates in those born since 1965 whose risks cannot yet be seen in national rates. Burdens in those born more recently will indicate the continuing occupational and environmental hazards under current asbestos control regulations. Our results confirm the major contribution of amosite to UK mesothelioma incidence and the substantial contribution of non-occupational exposure, particularly in women

    Heterogeneities from the first 100 million years recorded in deep mantle noble gases from the Northern Lau Back-arc Basin

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    Heavy noble gases (Ne, Ar, Xe) can record long-lasting heterogeneities in the mantle because of the production of isotopes from extant (238U, 40K) and extinct (129I and 244Pu)13 radionuclides. However, the presence of ubiquitous atmospheric contamination, particularly for ocean island basalts (OIBs) that sample the Earth’s deep mantle, have largely hampered precise characterization of the mantle source compositions. Here we present new high-precision noble gas data from gas-rich basalts erupted along the Rochambeau Rift in the northwestern corner of the Lau Basin. The strong influence of a deep mantle plume in the Rochambeau source is apparent from low 4He/3He ratios down to 25,600 (3He/4He of 28.1 RA). We find that the Rochambeau source is characterized by low ratios of radiogenic to non-radiogenic nuclides of Ne, Ar, and Xe (i.e., low 21Ne/22Ne, 40Ar/36Ar, and 129Xe/130Xe) compared to the mantle source of mid-ocean ridge basalts (MORBs). Additionally, we observe differences in elemental abundance patterns between the Rochambeau source and the mantle source of MORBs as characterized by the gas-rich popping rock from the Mid-Atlantic Ridge. However, the 3He/22Ne ratio of the Rochambeau plume source is significantly higher than the Iceland and Galapagos plume sources, while the 3He/36Ar and 3He/130Xe ratios appear to be similar. The difference in 3He/22Ne between Rochambeau and the Galapagos and Iceland plume sources could reflect long lasting accretional heterogeneities in the deep mantle or some characteristic of the back-arc mantle source. High-precision xenon isotopic measurements indicate that the lower 129Xe/130Xe ratios in the Rochambeau source cannot be explained solely by mixing atmospheric xenon with MORB31 type xenon; nor can fission-produced Xe be added to MORB Xe to produce the compositions seen in the Rochambeau basalts. Deconvolution of fissiogenic xenon isotopes demonstrate a higher proportion of Pu-derived fission Xe in the Rochambeau 33 source compared to the MORB source. Therefore, both I/Xe and Pu/Xe ratios are different between OIB and MORB mantle sources. Our observations require heterogeneous volatile accretion and a lower degree of processing for the mantle plume source compared to the MORB source. Since differences in 129Xe/130Xe ratios have to be produced while 129I is still alive, OIB and MORB sources were degassed at different rates for the first 100 Ma of Solar System history, and subsequent to this period, the two reservoirs have not been homogenized. In combination with recent results from the Iceland plume, our observations require the preservation of less-degassed, early-formed heterogeneities in the Earth’s deep mantle throughout Earth’s history

    Electrocardiographic safety evaluation of dihydroartemisinin piperaquine in the treatment of uncomplicated falciparum malaria.

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    Dihydroartemisinin-piperaquine (DP) could become a leading fixed combination malaria treatment worldwide. Although there is accumulating evidence of efficacy and safety from clinical trials, data on cardiotoxicity are limited. In two randomized controlled trials in Thailand, 56 patients had ECGs performed before treatment, 4 hours after the first dose, and 4 hours after the last dose. The mean (95% CI) changes in QTc interval (Bazett's correction) were 2 (-6 to 9) ms and 14 (7 to 21) ms, respectively. These small changes on the third day of treatment are similar to those observed elsewhere in the convalescent phase following antimalarial treatment with drugs known to have no cardiac effects and are therefore likely to result from recovery from acute malaria and not the treatment given. At therapeutic doses, DP does not have clinically significant effects on the electrocardiogram

    Реализация международных образовательных программ как условие развития полиязычной образовательной среды

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    Вызовы интернационализации высшего образования и науки ставят перед вузами-участниками "Проекта 5-100" задачи создания и развития полиязычной среды, которая позволит увеличить количество публикаций в международных журналах, будет способствовать разработке образовательных продуктов на английском языке для привлечения иностранных студентов и повышению мобильности студентов ипреподавателей университета. Привлечение и адаптация лучших образовательных практик зарубежных университетов способствует формированию профессиональных компетенций научно-педагогических работников университета в области преподавания на английском языке, разрабатывать образовательные курсы на основе современных международных стандартов. Опыт ТПУ в области реализации совместных образовательных программ с Университетом Саутгемптона (Великобритания), осуществляемых с 2012 г., позволяет улучшить качество выполнения задач развития университета в рамках Программы повышения конкурентоспособности ТПУ, учесть специфику профессиональной деятельности обучаемых - преподавателей-предметников, ведущих или планирующих вести занятия на английском языке и сконцентрироваться на разработке образовательных курсов на английском языке для магистратуры и бакалавриата, в том числе для программ с двойным дипломом

    The expected burden of mesothelioma mortality in Great Britain from 2002 to 2050

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    The British mesothelioma register contains all deaths from 1968 to 2001 where mesothelioma was mentioned on the death certificate. These data were used to predict the future burden of mesothelioma mortality in Great Britain. Poisson regression analysis was used to model male mesothelioma deaths from 1968 to 2001 as a function of the rise and fall of asbestos exposure during the 20th century, and hence to predict numbers of male deaths in the years 2002–2050. The annual number of mesothelioma deaths in Great Britain has risen increasingly rapidly from 153 deaths in 1968 to 1848 in 2001 and, using our preferred model, is predicted to peak at around 1950 to 2450 deaths per year between 2011 and 2015. Following this peak, the number of deaths is expected to decline rapidly. The eventual death rate will depend on the background level and any residual asbestos exposure. Between 1968 and 2050, there will have been approximately 90 000 deaths from mesothelioma in Great Britain, 65 000 of which will occur after 2001

    Bladder cancer mortality of workers exposed to aromatic amines: analysis of models of carcinogenesis.

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    The effects of various factors were evaluated on both relative risk (multiplicative model), and absolute excess risk (additive model) of bladder cancer among 664 workers of a dyestuff factory in Northern Italy. These workers were exposed to aromatic amines in fairly constant working conditions from 1922 to 1970, and were employed for at least one year. They were followed up till the end of 1981 for a total of 12,302 man-years at risk. Under both models, the risk was greater for workers directly involved in aromatic amine manufacture than for those with only intermittent exposure. There was no marked effect of age at first exposure on the absolute excess risk of bladder cancer, but the relative risk was strongly and negatively related to age at first exposure. Under the multistage theory of carcinogenesis, this pattern of risk indicates an early stage effect. Absolute excess risk increased sharply during exposure, and continued to rise, although less sharply, after exposure had ceased. Relative risk, however, decreased after cessation of exposure, indicating a possible late stage effect. Thus, the results derived from both additive and multiplicative models are not in contrast when interpreted in terms of the multistage theory of carcinogenesis, though they are not totally consistent with a single-stage effect, either early or late. Aromatic amines may act on a stage somewhere between the first and penultimate, or on more than one stage of the process of carcinogenesis. Alternatively, it is possible that imprecision in the job classification or other observational problems may obscure the trends, or produce fictitious trends in the effects of variables such as age at first exposure and time since last exposure. Finally, such a pattern of trends could emerge if there were only two stages and the first and penultimate stage were the same
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