405 research outputs found

    Manifesto on small airway involvement and management in asthma and chronic obstructive pulmonary disease: an Interasma (Global Asthma Association - GAA) and World Allergy Organization (WAO) document endorsed by Allergic Rhinitis and its Impact on Asthma (ARIA) and Global Allergy and Asthma European Network (GA2LEN)

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    Evidence that enables us to identify, assess, and access the small airways in asthma and chronic obstructive pulmonary disease (COPD) has led INTERASMA (Global Asthma Association) and WAO to take a position on the role of the small airways in these diseases. Starting from an extensive literature review, both organizations developed, discussed, and approved the manifesto, which was subsequently approved and endorsed by the chairs of ARIA and GA2LEN. The manifesto describes the evidence gathered to date and defines and proposes issues on small airway involvement and management in asthma and COPD with the aim of challenging assumptions, fostering commitment, and bringing about change. The small airways (defined as those with an internal diameter <2 mm) are involved in the pathogenesis of asthma and COPD and are the major determinant of airflow obstruction in these diseases. Various tests are available for the assessment of the small airways, and their results must be integrated to confirm a diagnosis of small airway dysfunction. In asthma and COPD, the small airways play a key role in attempts to achieve disease control and better outcomes. Small-particle inhaled formulations (defined as those that, owing to their size [usually <2 μm], ensure more extensive deposition in the lung periphery than large molecules) have proved beneficial in patients with asthma and COPD, especially those in whom small airway involvement is predominant. Functional and biological tools capable of accurately assessing the lung periphery and more intensive use of currently available tools are necessary. In patients with suspected COPD or asthma, small airway involvement must be assessed using currently available tools. In patients with subotpimal disease control and/or functional or biological signs of disease activity, the role of small airway involvement should be assessed and treatment tailored. Therefore, the choice between large- and small-particle inhaled formulations must reflect the physician’s considerations of disease features, phenotype, and response to previous therapy

    Solar Neutrino Constraints on the BBN Production of Li

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    Using the recent WMAP determination of the baryon-to-photon ratio, 10^{10} \eta = 6.14 to within a few percent, big bang nucleosynthesis (BBN) calculations can make relatively accurate predictions of the abundances of the light element isotopes which can be tested against observational abundance determinations. At this value of \eta, the Li7 abundance is predicted to be significantly higher than that observed in low metallicity halo dwarf stars. Among the possible resolutions to this discrepancy are 1) Li7 depletion in the atmosphere of stars; 2) systematic errors originating from the choice of stellar parameters - most notably the surface temperature; and 3) systematic errors in the nuclear cross sections used in the nucleosynthesis calculations. Here, we explore the last possibility, and focus on possible systematic errors in the He3(\alpha,\gamma)Be7 reaction, which is the only important Li7 production channel in BBN. The absolute value of the cross section for this key reaction is known relatively poorly both experimentally and theoretically. The agreement between the standard solar model and solar neutrino data thus provides additional constraints on variations in the cross section (S_{34}). Using the standard solar model of Bahcall, and recent solar neutrino data, we can exclude systematic S_{34} variations of the magnitude needed to resolve the BBN Li7 problem at > 95% CL. Additional laboratory data on He3(\alpha,\gamma)Be7 will sharpen our understanding of both BBN and solar neutrinos, particularly if care is taken in determining the absolute cross section and its uncertainties. Nevertheless, it already seems that this ``nuclear fix'' to the Li7 BBN problem is unlikely; other possible solutions are briefly discussed.Comment: 21 pages, 3 ps figure

    Elements of mathematics in problems. Through olympiads and circles to profession

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    This is a collection of teaching materials used in several Russian universities, schools, and mathematical circles. Most problems are chosen in such a way that in the course of the solution and discussion a reader learns important mathematical ideas and theories. The materials can be used by pupils and students for self-study, and by teachers. This is an abridged pre-copyedit version of the published book submitted with the permission of the publisher. Each included individual material is self-contained and ready-for-use. Solutions to problems are not included intentionally. This collection consolidates updates of several arXiv submissions, e.g., arXiv:1305.2598.Comment: Edited by A. Skopenkov, M. Skopenkov, A. Zaslavsky. In Russian. Optimized for printing on A5 paper. Moscow Center for Continuous Mathematical Education, 2018, 592pp (in Russian

    Nonlinear Integer Programming

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    Research efforts of the past fifty years have led to a development of linear integer programming as a mature discipline of mathematical optimization. Such a level of maturity has not been reached when one considers nonlinear systems subject to integrality requirements for the variables. This chapter is dedicated to this topic. The primary goal is a study of a simple version of general nonlinear integer problems, where all constraints are still linear. Our focus is on the computational complexity of the problem, which varies significantly with the type of nonlinear objective function in combination with the underlying combinatorial structure. Numerous boundary cases of complexity emerge, which sometimes surprisingly lead even to polynomial time algorithms. We also cover recent successful approaches for more general classes of problems. Though no positive theoretical efficiency results are available, nor are they likely to ever be available, these seem to be the currently most successful and interesting approaches for solving practical problems. It is our belief that the study of algorithms motivated by theoretical considerations and those motivated by our desire to solve practical instances should and do inform one another. So it is with this viewpoint that we present the subject, and it is in this direction that we hope to spark further research.Comment: 57 pages. To appear in: M. J\"unger, T. Liebling, D. Naddef, G. Nemhauser, W. Pulleyblank, G. Reinelt, G. Rinaldi, and L. Wolsey (eds.), 50 Years of Integer Programming 1958--2008: The Early Years and State-of-the-Art Surveys, Springer-Verlag, 2009, ISBN 354068274

    Effects of Dietary Restriction on Cancer Development and Progression

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    The effects of caloric restriction on tumor growth and progression are known for over a century. Indeed, fasting has been practiced for millennia, but just recently has emerged the protective role that it may exert toward cells. Fasting cycles are able to reprogram the cellular metabolism, by inducing protection against oxidative stress and prolonging cellular longevity. The reduction of calorie intake as well as short- or long-term fasting has been shown to protect against chronic and degenerative diseases, such as diabetes, cardiovascular pathologies, and cancer. In vitro and in vivo preclinical models showed that different restriction dietary regimens may be effective against cancer onset and progression, by enhancing therapy response and reducing its toxic side effects. Fasting-mediated beneficial effects seem to be due to the reduction of inflammatory response and downregulation of nutrient-related signaling pathways able to modulate cell proliferation and apoptosis. In this chapter, we will discuss the most significant studies present in literature regarding the molecular mechanisms by which dietary restriction may contribute to prevent cancer onset, reduce its progression, and positively affect the response to the treatments

    The effects of crop diversity and crop type on biological diversity in agricultural landscapes: a systematic review protocol.

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    Agricultural intensification is a well-known driver of biodiversity loss. Crop diversity and its changes over space and time drive land use intensity and impact biodiversity of agricultural landscapes, while meeting the growing demand for human food and nutrition resources. Loss of biodiversity in agricultural landscapes reduces primary productivity and soil health and erodes a range of other ecosystem services. At present, while having partial understanding of many processes, we lack a general synthesis of our knowledge of the links between crop diversity and biodiversity. We will therefore conduct a systematic review by searching multiple agriculture, ecology and environmental science databases (e.g. Web of Science, Geobase, Agris, AGRICOLA, GreenFILE) to identify studies reporting the impacts of crop diversity and crop type on the biological diversity of fauna and flora in agricultural landscapes. Response variables will include metrics of species richness, abundance, assemblage, community composition and species rarity. Screening, data coding and data extraction will be carried out by one researcher and a subset will be independently carried out by a second researcher for quality control. Study quality and risk of bias will be assessed. Evidence will first be mapped to species/taxa then assessed for further narrative or statistical synthesis based on comparability of results and likely robustness. Gaps in the evidence base will also be identified with a view toward future research and policy directions for nutrition, food systems and ecology

    Political leadership and the politics of performance:France, Syria and the chemical weapons crisis of 2013

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    This article draws upon developments in UK research on political rhetoric and political performance in order to examine the incident in 2013 when French President François Hollande committed French forces to a US-led punitive strike against Syria, after the use of chemical weapons in a Damascus suburb on 21 August. The US-led retaliation did not take place. This article analyses Hollande's declaration on 27 July and his TV appearance on 15 September. His rhetoric and style are best understood as generic to the nature of the presidential office of the Fifth Republic. The article concludes by appraising how analysis of the French case contributes to the developing literature on rhetoric, celebrity and performance
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