2,377 research outputs found

    Influence of Microlensing on Spectral Anomaly of Lensed Objects

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    Here we consider the influence of the microlensing on the spectrum of a lensed object taking into account that composite emission is coming from different regions arranged subsequently around the central source. We assumed that the lensed object has three regions with the black body emission; first the innermost with the highest temperature of 104K10^4K, second and third (located around the central) with slightly lower temperatures 7.5â‹…1037.5\cdot10^3 and 5â‹…1035\cdot10^3K, respectively. Than we explore the flux anomaly in lensed object due to microlensing. We compare U,V and B spectra of a such source. This results show that, due to microlensing, in a spectroscopically stratified object a flux anomaly is present.Comment: 4 pages, 2 figures, 1 tabl

    Forming norms: informing diagnosis and management in sports medicine

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    Clinicians aim to identify abnormalities, and distinguish harmful from harmless abnormalities. In sports medicine, measures of physical function such as strength, balance and joint flexibility are used as diagnostic tools to identify causes of pain and disability and monitor progression in response to an intervention. Comparing results from clinical measures against ‘normal’ values guides decision-making regarding health outcomes. Understanding ‘normal’ is therefore central to appropriate management of disease and disability. However, ‘normal’ is difficult to clarify and definitions are dependent on context. ‘Normal’ in the clinical setting is best understood as an appropriate state of physical function. Particularly as disease, pain and sickness are expected occurrences of being human, understanding ‘normal’ at each stage of the lifespan is essential to avoid the medicalisation of usual life processes. Clinicians use physical measures to assess physical function and identify disability. Accurate diagnosis hinges on access to ‘normal’ reference values for such measures. However our knowledge of ‘normal’ for many clinical measures in sports medicine is limited. Improved knowledge of normal physical function across the lifespan will assist greatly in the diagnosis and management of pain, disease and disability

    Investigating Cytoskeletal Alterations as a Potential Marker of Retinal and Lens Drug-Related Toxicity

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    Actin filaments play a critical role in the normal physiology of lenticular and retinal cells in the eye. Disruption of the actin cytoskeleton has been associated with retinal pathology and lens cataract formation. Ocular toxicity is an infrequent observation in drug safety studies, yet its impact to the drug development process is significant. Recognizing compounds through screening with a potential ocular safety liability is one way to prioritize development candidates while reducing development attrition. Lens epithelial cells from human, dog, and rat origins and retinal pigmented epithelium cells from human, monkey, and rat origins were cultured and investigated with immunocytochemical techniques. Cells were treated using noncytotoxic doses of the compound, fixed, stained for actin with rhodamine phalloidin, and counterstained for nuclei with TOTO-3, followed by confocal imaging. Tamoxifen and several experimental compounds known to be in vivo lens and retinal toxicants caused a reduction in F-actin fluorescence at noncytotoxic concentrations in all cells tested as observed by confocal microscopy. Developing an assay that predicts ocular toxicity helps the development process by prioritizing compounds for further investigation. Drug-induced cytoskeletal alterations may be useful as a potential safety-screening marker of retinal and lens toxicity. The knowledge of actin molecular biology and the application of other mechanistic screens to toxicology are discussed. Reducing this work to a high-throughput platform will enable chemists to select compounds with a reduced risk of ocular toxicity.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/63132/1/adt.2006.4.695.pd

    Towards domestic financing of national HIV responses lessons learnt from Serbia

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    This report highlights the efforts of Serbia to continue funding and implementation of the national HIV response which had been significantly supported by the GF from 2003 to 2014 and resulted in an intensified communication and consultation between governmental and NGO sector. Serbia has a long tradition in national HIV programming. There is clear evidence that the most effective programmes are those in which civil society's role, engagement in providing prevention, care and support services for key populations and PLHIV and established partnership with other relevant stakeholders are strongest and equitable. Moreover, interventions should be supported by enabling legal and policy frameworks. This includes measures to increase availability and access to different services and to minimize law enforcement and other structural barriers. Constant advocacy work with relevant stakeholders and standardization of services is also recognized as very important.sch_iihpub4571pu

    Generalized Hamiltonian structures for Ermakov systems

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    We construct Poisson structures for Ermakov systems, using the Ermakov invariant as the Hamiltonian. Two classes of Poisson structures are obtained, one of them degenerate, in which case we derive the Casimir functions. In some situations, the existence of Casimir functions can give rise to superintegrable Ermakov systems. Finally, we characterize the cases where linearization of the equations of motion is possible

    Derivation of the Effective Chiral Lagrangian for Pseudoscalar Mesons from QCD

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    We formally derive the chiral Lagrangian for low lying pseudoscalar mesons from the first principles of QCD considering the contributions from the normal part of the theory without taking approximations. The derivation is based on the standard generating functional of QCD in the path integral formalism. The gluon-field integration is formally carried out by expressing the result in terms of physical Green's functions of the gluon. To integrate over the quark-field, we introduce a bilocal auxiliary field Phi(x,y) representing the mesons. We then develop a consistent way of extracting the local pseudoscalar degree of freedom U(x) in Phi(x,y) and integrating out the rest degrees of freedom such that the complete pseudoscalar degree of freedom resides in U(x). With certain techniques, we work out the explicit U(x)-dependence of the effective action up to the p^4-terms in the momentum expansion, which leads to the desired chiral Lagrangian in which all the coefficients contributed from the normal part of the theory are expressed in terms of certain Green's functions in QCD. Together with the existing QCD formulae for the anomaly contributions, the present results leads to the complete QCD definition of the coefficients in the chiral Lagrangian. The relation between the present QCD definition of the p^2-order coefficient F_0^2 and the well-known approximate result given by Pagels and Stokar is discussed.Comment: 16 pages in RevTex, some typos are corrected, version for publication in Phys. Rev.

    Calculation of the Chiral Lagrangian Coefficients from the Underlying Theory of QCD: A Simple Approach

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    We calculate the coefficients in the chiral Lagrangian approximately from QCD based on a previous study of deriving the chiral Lagrangian from the first principles of QCD in which the chiral Lagrangian coefficients are defined in terms of certain Green's functions in QCD. We first show that, in the large N(c)-limit, the anomaly part contributions to the coefficients are exactly cancelled by certain terms in the normal part contributions, and the final results of the coefficients only concern the remaining normal part contributions depending on QCD interactions. We then do the calculation in a simple approach with the approximations of taking the large-N(c) limit, the leading order in dynamical perturbation theory, and the improved ladder approximation, thereby the relevant Green's functions are expressed in terms of the quark self energy. By solving the Schwinger-Dyson equation for the quark self energy, we obtain the approximate QCD predicted coefficients and the quark condensate which are consistent with the experimental values.Comment: Further typos corrected, to appear in Phys. Rev.
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