662 research outputs found

    Precise time and time interval users, requirements and specifications

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    The functional areas of application of Precise Time and Time Interval (PTTI) were considered and expanded. A comprehensive overview of the PTTI requirements and applications would provide an opportunity for individuals working in a specific functional area. Mutual problems, requirements, applications or successes shared by those in other functional areas were studied. Based upon the results of a two year study a compendium of PTTI requirements, applications and the means of meeting the requirements among Department of Defense components, other government agencies and major commercial users was compiled and is presented. It was found that the planning process for PTTI support for new acquisitions or new programs was less than a well defined, coordinated process. The processes are described in general terms and a generic model for requirements determination and subsequent coordination which may enhance the planning process and introduce cost benefits to the program is also presented

    Department of Defense Precise Time and Time Interval program improvement plan

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    The United States Naval Observatory is responsible for ensuring uniformity in precise time and time interval operations including measurements, the establishment of overall DOD requirements for time and time interval, and the accomplishment of objectives requiring precise time and time interval with minimum cost. An overview of the objectives, the approach to the problem, the schedule, and a status report, including significant findings relative to organizational relationships, current directives, principal PTTI users, and future requirements as currently identified by the users are presented

    Exclusive Lambda_b -> Lambda l^+ l^- decay in two Higgs doublet model

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    Rare Lambda_b -> Lambda l^+ l^- decay is investigated in framework of general two Higgs doublet model, in which a new source of CP violation exists (model III). The polarization parameter, CP asymmetry and decay width are calculated. It is shown that CP asymmetry is a very sensitive tool for establishing model III.Comment: 16 pages, 3 figures, LaTeX formatte

    Medicines adherence: Involving patients in decisions about prescribed medicines and supporting adherence

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    It is thought that between a third and a half of all medicines1 There are many causes of non-adherence but they fall into two overlapping categories: intentional and unintentional. Unintentional non-adherence occurs when the patient wants to follow the agreed treatment but is prevented from doing so by barriers that are beyond their control. Examples include poor recall or difficulties in understanding the instructions, problems with using the treatment, inability to pay for the treatment, or simply forgetting to take it. prescribed for long-term conditions are not taken as recommended. If the prescription is appropriate, then this may represent a loss to patients, the healthcare system and society. The costs are both personal and economic. Adherence presumes an agreement between prescriber and patient about the prescriber’s recommendations. Adherence to medicines is defined as the extent to which the patient’s action matches the agreed recommendations. Non-adherence may limit the benefits of medicines, resulting in lack of improvement, or deterioration, in health. The economic costs are not limited to wasted medicines but also include the knock-on costs arising from increased demands for healthcare if health deteriorates. Non-adherence should not be seen as the patient’s problem. It represents a fundamental limitation in the delivery of healthcare, often because of a failure to fully agree the prescription in the first place or to identify and provide the support that patients need later on. Addressing non-adherence is not about getting patients to take more medicines per se. Rather, it starts with an exploration of patients’ perspectives of medicines and the reasons why they may not want or are unable to use them. Healthcare professionals have a duty to help patients make informed decisions about treatment and use appropriately prescribed medicines to best effec

    Global alterations to the choroid plexus blood-CSF barrier in amyotrophic lateral sclerosis

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    © 2020 The Author(s). The choroid plexus (CP) is a highly vascularized structure located in the ventricles that forms the blood-CSF barrier (BCSFB) and separates the blood from the cerebrospinal fluid (CSF). In addition to its role as a physical barrier, the CP functions in CSF secretion, transport of nutrients into the central nervous system (CNS) and a gated point of entry of circulating immune cells into the CNS. Aging and neurodegeneration have been reported to affect CP morphology and function and increase protein leakage from blood to the CSF. Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease associated with both upper and lower motor neuron loss, as well as altered proteomic and metabolomic signatures in the CSF. The role of the BCSFB and the CP in ALS is unknown. Here we describe a transcriptomic and ultrastructural analysis of BCSFB and CP alterations in human postmortem tissues from ALS and non-neurologic disease controls. ALS-CP exhibited widespread disruptions in tight junctional components of the CP epithelial layer and vascular integrity. In addition, we detected loss of pericytes around ALS blood vessels, accompanied by activation of platelet aggregation markers vWF and Fibrinogen, reminiscent of vascular injury. To investigate the immune component of ALS-CP, we conducted a comprehensive analysis of cytokines and chemokine panels in CP lysates and found a significant down-regulation of M-CSF and V-CAM1 in ALS, as well as up-regulation of VEGF-A protein. This phenotype was accompanied by an infiltration of MERTK positive macrophages into the parenchyma of the ALS-CP when compared to controls. Taken together, we demonstrate widespread structural and functional disruptions of the BCSFB in human ALS increasing our understanding of the disease pathology and identifying potential new targets for ALS therapeutic development

    Higgs-photon associated production at eeˉe\bar{e} colliders

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    We present complete analytical expressions for the amplitudes of the process eeˉ→Hγe\bar{e}\rightarrow H\gamma. The calculation is performed using nonlinear gauges, which significantly simplifies both the actual analytical calculation and the check of its gauge invariance. After comparing our results with a previous numerical calculation, we extend the range of Higgs masses and center of mass energies to those appropriate to LEP 200 and a future linear collider.Comment: To appear in PRD. 18 pages latex, uses REVTEX; 5 postscript figure

    Detection of the heavy Higgs boson at γγ\gamma\gamma colliders

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    We consider the possibility of detecting a heavy Higgs boson (mH>2mZm_H>2m_Z) in proposed γγ\gamma\gamma colliders through the semi-leptonic mode γγ→H→ZZ→qqˉℓ+ℓ−\gamma\gamma \rightarrow H \rightarrow ZZ \rightarrow q\bar q \ell^+\ell^-. We show that due to the non-monochromatic nature of the photon beams produced by the laser-backscattering method, the resultant cross section for Higgs production is much smaller than the on-resonance cross section and generally {\it decreases} with increasing collider energy. Although continuum ZZZZ production is expected to be negligible, we demonstrate the presence of and calculate sizeable backgrounds from γγ→ℓ+ℓ−Z, qqˉZ\gamma\gamma\rightarrow \ell^+\ell^-Z,\,q\bar qZ, with Z→qqˉ, ℓ+ℓ−Z\rightarrow q\bar q,\,\ell^+\ell^-, respectively, and γγ→ttˉ→bbˉℓ+ℓ−ννˉ\gamma\gamma\rightarrow t\bar t\rightarrow b\bar b\ell^+\ell^-\nu\bar\nu. This channel may be used to detect a Higgs of mass mHm_H up to around 350~GeV at a 0.5~TeV e+e−e^+e^- collider, assuming a nominal yearly luminosity of 10--20~fb−1^{-1}.Comment: 18 pages (in RevTeX) plus Postscript figures (available by email or FAX), NUHEP-TH-92-29 and DOE-309-CPP-47. (Revised version: NO CHANGES to the manuscript, simply removed corrupted figure files

    The Neutron Electric Dipole Moment and CP-violating Couplings in the Supersymmetric Standard Model without R-parity

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    We analyze the neutron electric dipole moment (EDM) in the Minimal Supersymmetric Model with explicit R-parity violating terms. The leading contribution to the EDM occurs at the 2-loop level and is dominated by the chromoelectric dipole moments of quarks, assuming there is no tree-level mixings between sleptons and Higgs bosons or between leptons and gauginos. Based on the experimental constraint on the neutron EDM, we set limits on the imaginary parts of complex couplings λ′ijk{\lambda'}_{ijk} and λijk{\lambda}_{ijk} due to the virtual b-loop or tau-loop.Comment: final manuscript to appear in Phys. Rev. D, 15 pages, latex, 4 figures include

    Search for the intermediate Mass Higgs Signal at TeV eγe\gamma colliders

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    The intermediate mass Higgs (IMH) can be abundantly produced through the process e−γ→W−Hνe^-\gamma \rightarrow W^-H\nu at TeV e−γe^-\gamma colliders, which are realized by the laser back-scattering method. We search for the signature of W−H→(jj)(bbˉ)W^-H \rightarrow (jj)(b\bar b) plus missing transverse momentum, with and without considering the bb-tagging. We also analyse all the potential backgrounds from e−γ→W−Zν, W−W+e−, ZZe−, tˉbνe^-\gamma \rightarrow W^-Z\nu,\,W^-W^+e^-,\,ZZe^-,\, \bar t b\nu and ttˉe−t\bar t e^-. With our selective acceptance cuts these backgrounds are reduced to a manageable level. We find that for the entire intermediate mass range 60 -- 150~GeV the Higgs discovery should be viable. We also present detail formulas for the helicity amplitudes of these processes.Comment: Latex(Revtex), 30 pages, 8 figures in postscript format (uuencoded), NUHEP-TH-93-
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