2,848 research outputs found

    A review of laboratory and numerical modelling in volcanology

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    Modelling has been used in the study of volcanic systems for more than 100 years, building upon the approach first applied by Sir James Hall in 1815. Informed by observations of volcanological phenomena in nature, including eye-witness accounts of eruptions, geophysical or geodetic monitoring of active volcanoes, and geological analysis of ancient deposits, laboratory and numerical models have been used to describe and quantify volcanic and magmatic processes that span orders of magnitudes of time and space. We review the use of laboratory and numerical modelling in volcanological research, focussing on sub-surface and eruptive processes including the accretion and evolution of magma chambers, the propagation of sheet intrusions, the development of volcanic flows (lava flows, pyroclastic density currents, and lahars), volcanic plume formation, and ash dispersal. When first introduced into volcanology, laboratory experiments and numerical simulations marked a transition in approach from broadly qualitative to increasingly quantitative research. These methods are now widely used in volcanology to describe the physical and chemical behaviours that govern volcanic and magmatic systems. Creating simplified models of highly dynamical systems enables volcanologists to simulate and potentially predict the nature and impact of future eruptions. These tools have provided significant insights into many aspects of the volcanic plumbing system and eruptive processes. The largest scientific advances in volcanology have come from a multidisciplinary approach, applying developments in diverse fields such as engineering and computer science to study magmatic and volcanic phenomena. A global effort in the integration of laboratory and numerical volcano modelling is now required to tackle key problems in volcanology and points towards the importance of benchmarking exercises and the need for protocols to be developed so that models are routinely tested against real world data

    Experimental realisation of Shor's quantum factoring algorithm using qubit recycling

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    Quantum computational algorithms exploit quantum mechanics to solve problems exponentially faster than the best classical algorithms. Shor's quantum algorithm for fast number factoring is a key example and the prime motivator in the international effort to realise a quantum computer. However, due to the substantial resource requirement, to date, there have been only four small-scale demonstrations. Here we address this resource demand and demonstrate a scalable version of Shor's algorithm in which the n qubit control register is replaced by a single qubit that is recycled n times: the total number of qubits is one third of that required in the standard protocol. Encoding the work register in higher-dimensional states, we implement a two-photon compiled algorithm to factor N=21. The algorithmic output is distinguishable from noise, in contrast to previous demonstrations. These results point to larger-scale implementations of Shor's algorithm by harnessing scalable resource reductions applicable to all physical architectures.Comment: 7 pages, 3 figure

    Motivations and barriers to prosthesis users participation in physical activity, exercise and sport : a review of the literature

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    The UK will host the Paralympics in 2012 and the Commonwealth Games in 2014 showcasing the talents of elite athletes and aiming to inspire the population to become involved. However, low levels of physical activity (PA) are prevalent: only 40% of men and 28% of women meet the minimum UK recommendations. The limb absent population is no exception. To determine if people with limb amputations are participating in physical activity and sport; whether post-amputation activity levels match pre-amputation levels; and if there are motivations and barriers to participation. Study design: Literature review Five reviewers systematically search of peer reviewed and gray literature in seven bibliographic databases and the Cochrane Library. Results: Following rigorous elimination, 12 articles were finally included in the review and critically appraised. Four themes were identified: components, rehabilitation outcomes, body image and motivations and barriers to participation. People with limb absence are not participating in PA conducive to health benefits, and only a minority participate in exercise and sports. Participation following amputation does not mirror that of pre-amputation levels, and more barriers than motivations exist to adopting and maintaining a physically active lifestyle. This literature review aims to inform those involved in rehabilitation and ongoing care of those with limb absence about what motivates or precludes their participation in physical activity, exercise and sport. Such knowledge could be applied to improving health and well being in this population

    A Novel Mitigation Mechanism for Photo-Induced Trapping in an Anthradithiophene Derivative Using Additives

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    © 2020 Wiley-VCH GmbH A novel trap mitigation mechanism using molecular additives, which relieves a characteristic early turn-on voltage in a high-mobility p-type acene-based small-molecule organic semiconductor, when processed from hydrous solvents, is reported. The early turn-on voltage is attributed to photo-induced trapping, and additive incorporation is found to be very effective in suppressing this effect. Remarkably, the molecular additive does not disturb the charge transport properties of the small-molecule semiconductor, but rather intercalates in the crystal structure. This novel technique allows for the solution-processing of small molecular semiconductors from hydrous solvents, greatly simplifying manufacturing processes for large-area electronics. Along with various electric and spectroscopic characterization techniques, simulations have given a deeper insight into the trap mitigation effect induced by the additive

    Immunotherapy of lung cancer: An update

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    In Germany lung cancer is the leading cause of cancer-associated death in men. Surgery, chemotherapy and radiation may enhance survival of patients suffering from lung cancer but the enhancement is typically transient and mostly absent with advanced disease; eventually more than 90% of lung cancer patients will die of disease. New approaches to the treatment of lung cancer are urgently needed. Immunotherapy may represent one new approach with low toxicity and high specificity but implementation has been a challenge because of the poor antigenic characterization of these tumors and their ability to escape immune responses. Several different immunotherapeutic treatment strategies have been developed. This review examines the current state of development and recent advances with respect to non-specific immune stimulation, cellular immunotherapy ( specific and non-specific), therapeutic cancer vaccines and gene therapy for lung cancer. The focus is primarily placed on immunotherapeutic cancer treatments that are already in clinical trial or well progressed in preclinical studies. Although there seems to be a promising future for immunotherapy in lung cancer, presently there is not standard immunotherapy available for clinical routine

    Identification and manipulation of dynamic active site deficiency-induced competing reactions in electrocatalytic oxidation processes

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    A detrimental competition between the urea oxidation reaction (UOR) and oxygen evolution reaction is identified. Strategies are proposed to alleviate such competition and boost the performance of the UOR and other organic compound oxidation reactions

    A global framework for action to improve the primary care response to chronic non-communicable diseases: a solution to a neglected problem.

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    BACKGROUND: Although in developing countries the burden of morbidity and mortality due to infectious diseases has often overshadowed that due to chronic non-communicable diseases (NCDs), there is evidence now of a shift of attention to NCDs. DISCUSSION: Decreasing the chronic NCD burden requires a two-pronged approach: implementation of the multisectoral policies aimed at decreasing population-level risks for NCDs, and effective and affordable delivery of primary care interventions for patients with chronic NCDs. The primary care response to common NCDs is often unstructured and inadequate. We therefore propose a programmatic, standardized approach to the delivery of primary care interventions for patients with NCDs, with a focus on hypertension, diabetes mellitus, chronic airflow obstruction, and obesity. The benefits of this approach will extend to patients with related conditions, e.g. those with chronic kidney disease caused by hypertension or diabetes. This framework for a "public health approach" is informed by experience of scaling up interventions for chronic infectious diseases (tuberculosis and HIV). The lessons learned from progress in rolling out these interventions include the importance of gaining political commitment, developing a robust strategy, delivering standardised interventions, and ensuring rigorous monitoring and evaluation of progress towards defined targets. The goal of the framework is to reduce the burden of morbidity, disability and premature mortality related to NCDs through a primary care strategy which has three elements: 1) identify and address modifiable risk factors, 2) screen for common NCDs and 3) and diagnose, treat and follow-up patients with common NCDs using standard protocols. The proposed framework for NCDs borrows the same elements as those developed for tuberculosis control, comprising a goal, strategy and targets for NCD control, a package of interventions for quality care, key operations for national implementation of these interventions (political commitment, case-finding among people attending primary care services, standardised diagnostic and treatment protocols, regular drug supply, and systematic monitoring and evaluation), and indicators to measure progress towards increasing the impact of primary care interventions on chronic NCDs. The framework needs evaluation, then adaptation in different settings. SUMMARY: A framework for a programmatic "public health approach" has the potential to improve on the current unstructured approach to primary care of people with chronic NCDs. Research to establish the cost, value and feasibility of implementing the framework will pave the way for international support to extend the benefit of this approach to the millions of people worldwide with chronic NCDs

    Developmental changes in the role of different metalinguistic awareness skills in Chinese reading acquisition from preschool to third grade

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    Copyright @ 2014 Wei et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.The present study investigated the relationship between Chinese reading skills and metalinguistic awareness skills such as phonological, morphological, and orthographic awareness for 101 Preschool, 94 Grade-1, 98 Grade-2, and 98 Grade-3 children from two primary schools in Mainland China. The aim of the study was to examine how each of these metalinguistic awareness skills would exert their influence on the success of reading in Chinese with age. The results showed that all three metalinguistic awareness skills significantly predicted reading success. It further revealed that orthographic awareness played a dominant role in the early stages of reading acquisition, and its influence decreased with age, while the opposite was true for the contribution of morphological awareness. The results were in stark contrast with studies in English, where phonological awareness is typically shown as the single most potent metalinguistic awareness factor in literacy acquisition. In order to account for the current data, a three-stage model of reading acquisition in Chinese is discussed.National Natural Science Foundation of China and Knowledge Innovation Program of the Chinese Academy of Sciences

    Mental health first aid training of the public in a rural area: a cluster randomized trial [ISRCTN53887541]

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    BACKGROUND: A Mental Health First Aid course has been developed which trains members of the public in how to give initial help in mental health crisis situations and to support people developing mental health problems. This course has previously been evaluated in a randomized controlled trial in a workplace setting and found to produce a number of positive effects. However, this was an efficacy trial under relatively ideal conditions. Here we report the results of an effectiveness trial in which the course is given under more typical conditions. METHODS: The course was taught to members of the public in a large rural area in Australia by staff of an area health service. The 16 Local Government Areas that made up the area were grouped into pairs matched for size, geography and socio-economic level. One of each Local Government Area pair was randomised to receive immediate training while one served as a wait-list control. There were 753 participants in the trial: 416 in the 8 trained areas and 337 in the 8 control areas. Outcomes measured before the course started and 4 months after it ended were knowledge of mental disorders, confidence in providing help, actual help provided, and social distance towards people with mental disorders. The data were analysed taking account of the clustered design and using an intention-to-treat approach. RESULTS: Training was found to produce significantly greater recognition of the disorders, increased agreement with health professionals about which interventions are likely to be helpful, decreased social distance, increased confidence in providing help to others, and an increase in help actually provided. There was no change in the number of people with mental health problems that trainees had contact with nor in the percentage advising someone to seek professional help. CONCLUSIONS: Mental Health First Aid training produces positive changes in knowledge, attitudes and behaviour when the course is given to members of the public by instructors from the local health service

    Dietary soy and meat proteins induce distinct physiological and gene expression changes in rats

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    This study reports on a comprehensive comparison of the effects of soy and meat proteins given at the recommended level on physiological markers of metabolic syndrome and the hepatic transcriptome. Male rats were fed semi-synthetic diets for 1 wk that differed only regarding protein source, with casein serving as reference. Body weight gain and adipose tissue mass were significantly reduced by soy but not meat proteins. The insulin resistance index was improved by soy, and to a lesser extent by meat proteins. Liver triacylglycerol contents were reduced by both protein sources, which coincided with increased plasma triacylglycerol concentrations. Both soy and meat proteins changed plasma amino acid patterns. The expression of 1571 and 1369 genes were altered by soy and meat proteins respectively. Functional classification revealed that lipid, energy and amino acid metabolic pathways, as well as insulin signaling pathways were regulated differently by soy and meat proteins. Several transcriptional regulators, including NFE2L2, ATF4, Srebf1 and Rictor were identified as potential key upstream regulators. These results suggest that soy and meat proteins induce distinct physiological and gene expression responses in rats and provide novel evidence and suggestions for the health effects of different protein sources in human diets
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