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Chimera states in two populations with heterogeneous phase-lag

The simplest network of coupled phase-oscillators exhibiting chimera states is given by two populations with disparate intra- and inter-population coupling strengths. We explore the effects of heterogeneous coupling phase-lags between the two populations. Such heterogeneity arises naturally in various settings, for example, as an approximation to transmission delays, excitatory-inhibitory interact

Modeling of Kidney Hemodynamics : Probability-Based Topology of an Arterial Network

Through regulation of the extracellular fluid volume, the kidneys provide important long-term regulation of blood pressure. At the level of the individual functional unit (the nephron), pressure and flow control involves two different mechanisms that both produce oscillations. The nephrons are arranged in a complex branching structure that delivers blood to each nephron and, at the same time, prov

Basins of attraction for chimera states

Chimera states - curious symmetry-broken states in systems of identical coupled oscillators - typically occur only for certain initial conditions. Here we analyze their basins of attraction in a simple system comprised of two populations. Using perturbative analysis and numerical simulation we evaluate asymptotic states and associated destination maps, and demonstrate that basins form a complex tw

Characteristic Sizes of Life in the Oceans, from Bacteria to Whales

The size of an individual organism is a key trait to characterize its physiology and feeding ecology. Size-based scaling laws may have a limited size range of validity or undergo a transition from one scaling exponent to another at some characteristic size. We collate and review data on size-based scaling laws for resource acquisition, mobility, sensory range, and progeny size for all pelagic mari

Controlling chimeras

Coupled phase oscillators model a variety of dynamical phenomena in nature and technological applications. Non-local coupling gives rise to chimera states which are characterized by a distinct part of phase-synchronized oscillators while the remaining ones move incoherently. Here, we apply the idea of control to chimera states: using gradient dynamics to exploit drift of a chimera, it will attain

Vem var mest världsberömd - Cassel eller Keynes?

John Maynard Keynes brukar betraktas som världens mest berömde nationalekonom under mellankrigstiden och kanske hela 1900-talet. I början av 1920-talet lyste emellertid ett annat namn minst lika kraftigt på ekonomernas stjärnhimmel – Gustav Cassel. I denna artikel används omnämnanden av de båda ekonomerna i tidskriften The Economist som måttstock för att bedöma vem av de båda som var mest berömd p

Superdevalveringen 1982: Sverige under IMF-luppen

Sverige hade sedan länge varit en pålitlig medlem av Internationella valutafonden när den tillträdande socialdemokratiska regeringen 1982 slog till med en 16-procentig devalvering som utlöste febril aktivitet i förhållandet mellan Sverige och fonden. IMF genomförde en särskilt konsultation och devalveringen diskuterades tre gånger i fondens direktion. Såväl Sverige som IMF lyckades emellertid vänd

Hydrophobic interactions control the self-assembly of DNA and cellulose

Desoxyribosenucleic acid, DNA, and cellulose molecules self-assemble in aqueous systems. This aggregation is the basis of the important functions of these biological macromolecules. Both DNA and cellulose have significant polar and nonpolar parts and there is a delicate balance between hydrophilic and hydrophobic interactions. The hydrophilic interactions related to net charges have been thoroughl

Lung Mast Cells Have a High Constitutive Expression of Carboxypeptidase A3 mRNA That Is Independent from Granule-Stored CPA3

The mast cell granule metalloprotease CPA3 is proposed to have important tissue homeostatic functions. However, the basal CPA3 mRNA and protein expression among mast cell populations has remained poorly investigated. Using a novel histology-based methodology that yields quantitative data on mRNA and protein expression at a single-cell level, the present study maps CPA3 mRNA and protein throughout

Critical challenges in implementing sustainable transport policy in Stockholm and Gothenburg

This paper explores the mental-models of Swedish planners in order to understand the extent to which they support the ideals of sustainable transport. Focussing on three critical challenges: forecast-led versus vision-led planning; tackling congestion; and, public acceptability; the findings, drawn from in-depth interviews, demonstrate mostly advanced thinking. However, implementation can be at od

Regulation of HPV16 Early Gene Expression

Human papillomavirus type 16 (HPV16) is the most common high-risk type and isassociated with more than 50% cervical cancer cases as well as a number of headand neck cancer cases. The life cycle of HPV16 is strictly linked to celldifferentiation in the squamous epithelium with expression of the HPV16 earlygenes. The oncoproteins E6 and E7 are essential for preventing apoptosis andinducing prolifera

Methodology for developing reduced reaction mechanisms, and their use in combustion simulations

Combustion, present in a vast majority of energy and material production as well as in transportation, represents a foundation of our modern society. To improve and optimize the applications relying on combustion demand a high level of knowledge, and an ability to simulate the combustion process. To do so three-dimensional Computational Fluid Dynamic (CFD) combustion simulations can be used, whereCombustion, present in a vast majority of energy and material production as well as in transportation, represents a foundation of our modern society. To improve and optimize the applications relying on combustion demand a high level of knowledge, and an ability to simulate the combustion process. To do so three-dimensional Computational Fluid Dynamic (CFD) combustion simulations can be used, where

Investigating agency: methodological and empirical challenges

The promise of connecting agency and structure in studies of regional development is to disentangle causal effects and to better understand to what extent and how individuals, groups of individuals, and organisations can shape regional trajectories. This is not without challenges because agency and structure are deep theoretical constructs, which are not easily translated into empirical research.

Distinct mechanisms of resistance to fulvestrant treatment dictate level of ER independence and selective response to CDK inhibitors in metastatic breast cancer

BACKGROUND: Resistance to endocrine treatment in metastatic breast cancer is a major clinical challenge. Clinical tools to predict both drug resistance and possible treatment combination approaches to overcome it are lacking. This unmet need is mainly due to the heterogeneity underlying both the mechanisms involved in resistance development and breast cancer itself.METHODS: To study the complexity

Identification of Extracellular Matrix Proteins Secreted by Human Dermal Fibroblasts Cultured in 3D Electrospun Scaffolds

The appreciation that cell interactions in tissues is dependent on their three dimensional (3D) distribution has stimulated the development of 3D cell culture models. We constructed an artificial 3D tumour by culturing human breast cancer JIMT-1 cells and human dermal fibroblasts (HDFs) in a 3D network of electrospun polycaprolactone fibres. Here, we investigate ECM components produced by the cell

Human epidermal growth factor receptor-3 expression is regulated at transcriptional level in breast cancer settings by junctional adhesion molecule-a via a pathway involving beta-catenin and foxa1

The success of breast cancer therapies targeting the human epidermal growth factor receptor-2 (HER2) is limited by the development of drug resistance by mechanisms including upregulation of HER3. Having reported that HER2 expression and resistance to HER2-targeted therapies can be regulated by Junctional Adhesion Molecule-A (JAM-A), this study investigated if JAM-A regulates HER3 expression. Expre