Mutual selection in time-varying networks

Copyright @ 2013 American Physical SocietyTime-varying networks play an important role in the investigation of the stochastic processes that occur on complex networks. The ability to formulate the development of the network topology on the same time scale as the evolution of the random process is important for a variety of applications, including the spreading of diseases. Past contributions have investigated random processes on time-varying networks with a purely random attachment mechanism. The possibility of extending these findings towards a time-varying network that is driven by mutual attractiveness is explored in this paper. Mutual attractiveness models are characterized by a linking function that describes the probability of the existence of an edge, which depends mutually on the attractiveness of the nodes on both ends of that edge. This class of attachment mechanisms has been considered before in the fitness-based complex networks literature but not on time-varying networks. Also, the impact of mutual selection is investigated alongside opinion formation and epidemic outbreaks. We find closed-form solutions for the quantities of interest using a factorizable linking function. The voter model exhibits an unanticipated behavior as the network never reaches consensus in the case of mutual selection but stays forever in its initial macroscopic configuration, which is a further piece of evidence that time-varying networks differ markedly from their static counterpart with respect to random processes that take place on them. We also find that epidemic outbreaks are accelerated by uncorrelated mutual selection compared to previously considered random attachment

The relation between cholesterol and haemorrhagic or ischaemic stroke in the Renfrew/Paisley study

Studies have found little association between cholesterol and overall stroke risk, but this could be attributable to different relations for haemorrhagic and ischaemic stroke. Stroke mortality data from prospective studies cannot usually be divided into stroke subtypes. We have therefore analysed stroke based on hospital admissions, obtained by computerised linkage with acute hospital discharges in Scotland for a large prospective cohort study

UNDP-GEF Grasslands Project: The Southern Africa Botanical Network SABONET

This six-year biodiversity capacity building project closes at the end of June 2005. The principal outcomes have been greatly strengthened capacities within, and interaction between, the national herbaria of southern Africa, in order to improve plant taxonomic outputs to better serve the needs of conservation end-users. Grassland plants have in many ways been the main regional focus. The project was based in the National Botanical Institute (NBI) of Southern Africa (now the South Africa Biodiversity Institute - SANBI) and had components in Angola, Botswana, Lesotho, Malawi, Mozambique, Namibia, Swaziland, Zambia and Zimbabwe. The NBI provide regional coordination and technical support

Local molecular field theory for the treatment of electrostatics

We examine in detail the theoretical underpinnings of previous successful applications of local molecular field (LMF) theory to charged systems. LMF theory generally accounts for the averaged effects of long-ranged components of the intermolecular interactions by using an effective or restructured external field. The derivation starts from the exact Yvon-Born-Green hierarchy and shows that the approximation can be very accurate when the interactions averaged over are slowly varying at characteristic nearest-neighbor distances. Application of LMF theory to Coulomb interactions alone allows for great simplifications of the governing equations. LMF theory then reduces to a single equation for a restructured electrostatic potential that satisfies Poisson's equation defined with a smoothed charge density. Because of this charge smoothing by a Gaussian of width sigma, this equation may be solved more simply than the detailed simulation geometry might suggest. Proper choice of the smoothing length sigma plays a major role in ensuring the accuracy of this approximation. We examine the results of a basic confinement of water between corrugated wall and justify the simple LMF equation used in a previous publication. We further generalize these results to confinements that include fixed charges in order to demonstrate the broader impact of charge smoothing by sigma. The slowly-varying part of the restructured electrostatic potential will be more symmetric than the local details of confinements.Comment: To be published in J Phys-Cond Matt; small misprint corrected in Eq. (12) in V

CVD Screening Protocol for History of Hypertension in Pregnancy

The American College of Obstetricians and Gynecologists (ACOG) and the American Heart Association (AHA) recommend women with a history of hypertension during pregnancy receive annual blood pressure monitoring, weight check, and lipid screening; remain in the optimal body mass index (BMI) range; and obtain education on future risks for cardiovascular disease (CVD). At a small, Midwestern primary care clinic, there is not a current process in place to ensure patient education and screenings are provided for patients who meet this criterion. For this project, two check boxes were added to the providers’ annual exam template in the electronic health record (EHR) to indicate history of hypertension in pregnancy and indication that education was provided. Providers were introduced to the practice change by PowerPoint presentation. To evaluate the project, data was collected and provided by the clinic’s Quality and Data Analyst RN, including provider participation, percent of total women screened, and compliance with practice change. Only 20% of providers utilized the documentation changes; therefore, all other data analysis was insignificant. We recommend an on-site project team or individual who can encourage compliance, monthly auditing, and feedback to each provider regarding their individual performance

Understanding cross‐border mergers and acquisitions of African firms : the role of dynamic capabilities in enabling competitiveness amidst contextual constraints

This article builds on existing international business literature that examines the drivers of cross‐border mergers and acquisitions (M&As) within emerging and developing economy contexts, theoretically exploring how dynamic capabilities (DCs) are connected to these drivers, and how African emerging multinational enterprises (EMNEs) can pursue them to achieve competitiveness. The article's contribution is the development of a DC framework and testable propositions for African EMNEs' cross‐border M&As. The theoretical framework shows the division of DC dimensions—sensing, seizing, and transforming—and establishes explanations for their linkage with institutional and resource drivers for African EMNEs' cross‐border M&A competitiveness. In addition, the article outlines managerial implications to this effect. Overall, the article contributes to the emerging literature on the international expansion of African EMNEs through cross‐border M&As by underscoring the role of DCs.©2020 The Authors. Thunderbird International Business Review published by Wiley Periodicals LLC. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the origina l work is properly cited.fi=vertaisarvioitu|en=peerReviewed

A Numerical Study of the Hierarchical Ising Model: High Temperature Versus Epsilon Expansion

We study numerically the magnetic susceptibility of the hierarchical model with Ising spins ($\sigma =\pm 1$) above the critical temperature and for two values of the epsilon parameter. The integrations are performed exactly, using recursive methods which exploit the symmetries of the model. Lattices with up to $2^18$ sites have been used. Surprisingly, the numerical data can be fitted very well with a simple power law of the form $(1- \beta /\beta _c )^{- \gamma}$for the {\it whole} temperature range. The numerical values for $\gamma$ agree within a few percent with the values calculated with a high-temperature expansion but show significant discrepancies with the epsilon-expansion. We would appreciate comments about these results.Comment: 15 Pages, 12 Figures not included (hard copies available on request), uses phyzzx.te