902 research outputs found

    Dispersion γZ\gamma Z-box correction to the weak charge of the proton

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    We consider elastic scattering of electrons off a proton target. The parity violating (PV) asymmetry arises at leading order in α\alpha due to interference of γ\gamma and ZZ exchange. The radiative corrections to this leading mechanism were calculated in the literature and included in experimental analyses, except for γZ\gamma Z box and cross-box contributions. We present here a dispersion calculation of these corrections in forward kinematics. We demonstrate that at the GeV energies of current PV experiments, such corrections are not suppressed by the small vector weak charge of the electron, as occurs in the atomic PV. Our results suggest that the current theoretical uncertainty in the analysis of the QWEAK experiment might be substantially underestimated, and more accurate account of the dispersion corrections are needed in order to interprete the PV data.Comment: 4 pages, 3 figures, revtex

    Mechanical cell-matrix feedback explains pairwise and collective endothelial cell behavior in vitro

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    In vitro cultures of endothelial cells are a widely used model system of the collective behavior of endothelial cells during vasculogenesis and angiogenesis. When seeded in an extracellular matrix, endothelial cells can form blood vessel-like structures, including vascular networks and sprouts. Endothelial morphogenesis depends on a large number of chemical and mechanical factors, including the compliancy of the extracellular matrix, the available growth factors, the adhesion of cells to the extracellular matrix, cell-cell signaling, etc. Although various computational models have been proposed to explain the role of each of these biochemical and biomechanical effects, the understanding of the mechanisms underlying in vitro angiogenesis is still incomplete. Most explanations focus on predicting the whole vascular network or sprout from the underlying cell behavior, and do not check if the same model also correctly captures the intermediate scale: the pairwise cell-cell interactions or single cell responses to ECM mechanics. Here we show, using a hybrid cellular Potts and finite element computational model, that a single set of biologically plausible rules describing (a) the contractile forces that endothelial cells exert on the ECM, (b) the resulting strains in the extracellular matrix, and (c) the cellular response to the strains, suffices for reproducing the behavior of individual endothelial cells and the interactions of endothelial cell pairs in compliant matrices. With the same set of rules, the model also reproduces network formation from scattered cells, and sprouting from endothelial spheroids. Combining the present mechanical model with aspects of previously proposed mechanical and chemical models may lead to a more complete understanding of in vitro angiogenesis.Comment: 25 pages, 6 figures, accepted for publication in PLoS Computational Biolog

    Visual and personalized quality of life assessment app for people with severe mental health problems:Qualitative evaluation

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    Background:  QoL-ME is a digital visual personalized quality of life assessment app for people with severe mental health problems. Research reveals that e-mental health apps frequently suffer from low engagement and fall short of expectations regarding their impact on patients' daily lives. Studies often indicate that e-mental health apps ought to respect the needs and preferences of end users to achieve optimal user engagement. Objective:  The aim of this study was to explore the experiences of users regarding the usability and functionality of QoL-ME and whether the app is actionable and beneficial for patients. Methods:  End users (n=8) of QoL-ME contributed to semistructured interviews. An interview guide was used to direct the interviews. All interviews were audiorecorded and transcribed verbatim. Transcriptions were analyzed and coded thematically. Results:  Analysis revealed 3 main themes: (1) benefit, (2) actionability, and (3) characteristics of the QoL-ME. The first theme reveals that the QoL-ME app was beneficial for the majority of respondents, primarily by prompting them to reflect on their quality of life. The current version is not yet actionable; the actionability of the QoL-ME app may be improved by enabling users to view their scores over time and by supplying practical advice for quality of life improvements. Overall, participants had positive experiences with the usability, design, and content of the app. Conclusions:  The QoL-ME app can be beneficial to users as it provides them with insight into their quality of life and elicits reflection. Incorporating more functionalities that facilitate self-management, such as advice and strategies for improving areas that are lacking, will likely make the app actionable. Patients positively regarded the usability, design, and contents of the QoL-ME app

    Reorganizing and integrating public health, health care, social care and wider public services:A theory-based framework for collaborative adaptive health networks to achieve the triple aim

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    Forty-one studies were included. Eight components were identified: social forces, resources, finance, relations, regulations, market, leadership, and accountability. Each component consists of three or more subcomponents, providing insight into (1) the (sub)component-specific strategies that accelerate PHM development, (2) the necessary contextual factors and mechanisms for these strategies to be successful and (3) the extracted theories that underlie the (sub)component-specific SCMO configurations. These theories originate from a wide variety of scientific disciplines. We bring these (sub)components together into what we call the Collabroative Adaptive Health Network (CAHN) framework

    Pharmacokinetics of amphotericin B after accidental overdose in an adult critically ill patient treated with plasmapheresis: a case report and review of literature

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    Amphotericin B is a broad-spectrum antifungal agent that is used in the treatment of systemic fungal infections. We describe the case of a 62-year-old female patient with recent aneurysmal subarachnoid hemorrhage who was treated for suspected ventriculitis and a fungal coinfection. Instead of liposomal amphotericin B (L-AmB), 465 mg (5 mg/kg) amphotericin B deoxycholate (DOC) was inadvertently administered, leading to refractory shock with multiple organ failure and requiring mechanical ventilation. Since an overdose of amphotericin B can lead to fatal consequences and has a half-life of 15 days, plasmapheresis was started. The serum concentration decreased from 1.32 µg/mL to 0.62 µg/mL before plasmapheresis, demonstrating a mean half-life of 49 hours. After two plasmapheresis sessions, the serum concentration further dropped to 0.26 µg/mL, demonstrating a mean half-life of 17 hours. In contrast, the third plasmapheresis session had no effect on serum concentration. The patient made a full recovery, potentially facilitated by enhanced amphotericin B elimination through plasmapheresis. Positive outcomes were previously reported in two adult patients treated with plasmapheresis. However, other reports without plasmapheresis described fatal outcomes in adult patients, albeit with a twofold overdose compared to the two patients successfully treated with plasmapheresis. Moreover, plasmapheresis itself carries risks such as hypocalcemia, metabolic alkalosis, and coagulation deficits. Consequently, the role of plasmapheresis in amphotericin B overdose is still debated

    Constraints on a Parity-Conserving/Time-Reversal-Non-Conserving Interaction

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    Time-Reversal-Invariance non-conservation has now been unequivocally demonstrated in a direct measurement at CPLEAR. What about tests of time-reversal-invariance in systems other than the kaon system? Tests of time-reversal-invariance belong to two classes: searches for parity violating (P-odd)/time-reversal-invariance-odd (T-odd) interactions, and for P-even/T-odd interactions (assuming CPT conservation this implies C-conjugation non-conservation). Limits on a P-odd/T-odd interaction follow from measurements of the electric dipole moment of the neutron (with a present upper limit of 6 x 10^-26 e.cm [95% C.L.]). It provides a limit on a P-odd/T-odd pion-nucleon coupling constant which is less than 10^-4 times the weak interaction strength. Experimental limits on a P-even/T-odd interaction are much less stringent. Following the standard approach of describing the nucleon-nucleon interaction in terms of meson exchanges, it can be shown that only charged rho-meson exchange and A_1 meson exchange can lead to a P-even/T-odd interaction. The better constraints stem from measurements of the electric dipole moment of the neutron and from measurements of charge-symmetry breaking in neutron-proton elastic scattering. The latter experiments were executed at TRIUMF (497 and 347 MeV) and at IUCF (183 MeV). Weak decay experiments may provide limits which will possibly be comparable. All other experiments, like gamma decay experiments, detailed balance experiments, polarization - analyzing power difference determinations, and five-fold correlation experiments with polarized incident nucleons and aligned nuclear targets, have been shown to be at least an order of magnitude less sensitive.Comment: 15 pages LaTeX, including 5 PostScript figures. Uses ijmpe1.sty. To appear in International Journal of Modern Physics E (IJMPE). Slight change in short abstrac

    Implementing population health managemen

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    Purpose The purpose of this paper is to gain insight into how population health management (PHM) strategies can successfully integrate and reorganize public health, health care, social care and community services to improve population health and quality of care while reducing costs growth, this study compared four large-scale transformation programs: Greater Manchester Devolution, Vancouver Healthy City Strategy, Gen-H Cincinnati and Gesundes Kinzigtal. Design/methodology/approach Following the realist methodology, this explorative comparative case-study investigated PHM initiatives' key features and participants' experiences of developing such initiatives. A semi-structured interview guideline based on a theoretical framework for PHM guided the interviews with stakeholders (20) from different sectors. Findings Five initial program theories important to the development of PHM were formulated: (1) create trust in a shared vision and understanding of the PHM rationale to establish stakeholders' commitment to the partnership; (2) create shared ownership for achieving the initiative's goals; (3) create shared financial interest that reduces perceived financial risks to provide financial sustainability; (4) create a learning environment to secure initiative's credibility and (5) create citizens' and professionals' awareness of the required attitudes and behaviours. Originality/value The study highlights initial program theories for the implementation of PHM including different strategies and structures underpinning the initiatives. These insights provide a deeper understanding of how large-scale transformation could be developed

    Do conceptualisations of health differ across social strata? A concept mapping study among lay people.

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    The legitimacy of policies that aim at tackling socioeconomic inequalities in health can be challenged if they do not reflect the conceptualisations of health that are valued in all strata. Therefore, this study analyses how different socioeconomic groups formulate their own answers regarding: what does health mean to you
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