422 research outputs found

    Periconception endogenous and exogenous maternal sex steroid hormones and risk of asthma and allergy in offspring : protocol for a systematic review and meta-analysis

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    Introduction Pregnancy is associated with several hormonal changes which influence the developing fetus. Variations in maternal endogenous hormones and prepregnancy use of hormonal preparations have been linked to asthma and allergy in the offspring, but findings are inconsistent. We plan to undertake a systematic review to synthesise the evidence on the association between endogenous and exogenous maternal sex hormones and the risk of asthma and allergy in the offspring. Methods and analysis We will search Medline, Embase, Cochrane Library, Institute of Scientific Information Web of Science, Cumulative Index of Nursing and Allied Health, Scopus, Google Scholar, Allied and Complementary Medicine Database, Global Health, Psychological Information (PsycINFO), Centre for Agriculture and Bioscience (CAB) International and WHO Global Health Library from inception until 2016 to identify relevant studies on the topic. Additional studies will be identified by searching databases of proceedings of international conferences, contacting international experts in the field and searching the references cited in identified studies. We will include analytical epidemiological studies. Two researchers will independently screen identified studies, undertake data extraction and assess risk of bias in eligible studies, while a third reviewer will arbitrate any disagreement. We will use the Effective Public Health Practice Project tool to assess the risk of bias in the studies. We will perform a random-effects meta-analysis to synthesise the evidence. We will use the Grading of Recommendations Assessment, Development and Evaluation approach to rate the strength and quality of the overall evidence with respect to each outcome. Ethics and dissemination Ethical approval is not required since the study is a systematic review of published literature. Our findings will be reported in a peer-reviewed scientific journal.Peer reviewe

    Educating professionals to support self-management in people with asthma or diabetes: protocol for a systematic review and scoping exercise

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    This report is independent research funded by the National Institute for Health Research (Programme Development Grants, Implementing supported asthma self-management in routine clinical care: designing, refining, piloting and evaluating a whole systems implementation within an MRC Phase IV programme of research, RP-DG-1213-10008). The views expressed in this publication are those of the author(s) and not necessarily those of the NHS, the National Institute for Health Research or the Department of Health. This work is sponsored by the University of Edinburgh. The funder and sponsor have not had any role in developing the protocol

    On the integral cohomology of smooth toric varieties

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    Let XΣX_\Sigma be a smooth, not necessarily compact toric variety. We show that a certain complex, defined in terms of the fan Σ\Sigma, computes the integral cohomology of XΣX_\Sigma, including the module structure over the homology of the torus. In some cases we can also give the product. As a corollary we obtain that the cycle map from Chow groups to integral Borel-Moore homology is split injective for smooth toric varieties. Another result is that the differential algebra of singular cochains on the Borel construction of XΣX_\Sigma is formal.Comment: 10 page

    Loop Groups, Kaluza-Klein Reduction and M-Theory

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    We show that the data of a principal G-bundle over a principal circle bundle is equivalent to that of a \hat{LG} = U(1) |x LG bundle over the base of the circle bundle. We apply this to the Kaluza-Klein reduction of M-theory to IIA and show that certain generalized characteristic classes of the loop group bundle encode the Bianchi identities of the antisymmetric tensor fields of IIA supergravity. We further show that the low dimensional characteristic classes of the central extension of the loop group encode the Bianchi identities of massive IIA, thereby adding support to the conjectures of hep-th/0203218.Comment: 26 pages, LaTeX, utarticle.cls, v2:clarifications and refs adde

    Knaster's problem for (Z2)k(Z_2)^k-symmetric subsets of the sphere S2k1S^{2^k-1}

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    We prove a Knaster-type result for orbits of the group (Z2)k(Z_2)^k in S2k1S^{2^k-1}, calculating the Euler class obstruction. Among the consequences are: a result about inscribing skew crosspolytopes in hypersurfaces in R2k\mathbb R^{2^k}, and a result about equipartition of a measures in R2k\mathbb R^{2^k} by (Z2)k+1(Z_2)^{k+1}-symmetric convex fans

    The Serre spectral sequence of a noncommutative fibration for de Rham cohomology

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    For differential calculi on noncommutative algebras, we construct a twisted de Rham cohomology using flat connections on modules. This has properties similar, in some respects, to sheaf cohomology on topological spaces. We also discuss generalised mapping properties of these theories, and relations of these properties to corings. Using this, we give conditions for the Serre spectral sequence to hold for a noncommutative fibration. This might be better read as giving the definition of a fibration in noncommutative differential geometry. We also study the multiplicative structure of such spectral sequences. Finally we show that some noncommutative homogeneous spaces satisfy the conditions to be such a fibration, and in the process clarify the differential structure on these homogeneous spaces. We also give two explicit examples of differential fibrations: these are built on the quantum Hopf fibration with two different differential structures.Comment: LaTeX, 33 page

    Representation theory of finite W algebras

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    In this paper we study the finitely generated algebras underlying WW algebras. These so called 'finite WW algebras' are constructed as Poisson reductions of Kirillov Poisson structures on simple Lie algebras. The inequivalent reductions are labeled by the inequivalent embeddings of sl2sl_2 into the simple Lie algebra in question. For arbitrary embeddings a coordinate free formula for the reduced Poisson structure is derived. We also prove that any finite WW algebra can be embedded into the Kirillov Poisson algebra of a (semi)simple Lie algebra (generalized Miura map). Furthermore it is shown that generalized finite Toda systems are reductions of a system describing a free particle moving on a group manifold and that they have finite WW symmetry. In the second part we BRST quantize the finite WW algebras. The BRST cohomology is calculated using a spectral sequence (which is different from the one used by Feigin and Frenkel). This allows us to quantize all finite WW algebras in one stroke. Explicit results for sl3sl_3 and sl4sl_4 are given. In the last part of the paper we study the representation theory of finite WW algebras. It is shown, using a quantum version of the generalized Miura transformation, that the representations of finite WW algebras can be constructed from the representations of a certain Lie subalgebra of the original simple Lie algebra. As a byproduct of this we are able to construct the Fock realizations of arbitrary finite WW algebras.Comment: 62 pages, THU-92/32, ITFA-28-9

    Cohomological tautness for Riemannian foliations

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    In this paper we present some new results on the tautness of Riemannian foliations in their historical context. The first part of the paper gives a short history of the problem. For a closed manifold, the tautness of a Riemannian foliation can be characterized cohomologically. We extend this cohomological characterization to a class of foliations which includes the foliated strata of any singular Riemannian foliation of a closed manifold
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