Transitional cluster dynamics in a model for delay-coupled chemical oscillators.

Cluster synchronization is a fundamental phenomenon in systems of coupled oscillators. Here, we investigate clustering patterns that emerge in a unidirectional ring of four delay-coupled electrochemical oscillators. A voltage parameter in the experimental setup controls the onset of oscillations via a Hopf bifurcation.

Accession Site Does Not Influence the Risk of Stroke after Diagnostic Coronary Angiography or Intervention: Results from a Large Prospective Registry.

Introduction: Periprocedural stroke represents a rare but serious complication of cardiac catheterization. Pooled data from randomized trials evaluating the risk of stroke following cardiac catheterization via transradial versus transfemoral access showed no difference. On the other hand, a significant difference in stroke rates favoring transradial access was found in a recent meta-analysis of observational studies.

Symmetries and cluster synchronization in multilayer networks.

Real-world systems in epidemiology, social sciences, power transportation, economics and engineering are often described as multilayer networks. Here we first define and compute the symmetries of multilayer networks, and then study the emergence of cluster synchronization in these networks. We distinguish between independent layer symmetries, which occur in one layer and are independent of the other layers, and dependent layer symmetries, which involve nodes in different layers.

Mapping regional strain in anesthetised healthy subjects during spontaneous ventilation.

Introduction: Breathing produces a phenomenon of cyclic deformation throughout life. Biomechanically, deformation of the lung is measured as strain. Regional strain recently started to be recognised as a tool in the study of lung pathophysiology, but regional lung strain has not been studied in healthy subjects breathing spontaneously without voluntary or pharmacological control of ventilation.

Cluster Synchronization in Multilayer Networks: A Fully Analog Experiment with LC Oscillators with Physically Dissimilar Coupling.

We investigate cluster synchronization in experiments with a multilayer network of electronic Colpitts oscillators, specifically a network with two interaction layers. We observe and analytically characterize the appearance of several cluster states as we change coupling in the layers. In this study, we innovatively combine bifurcation analysis and the computation of transverse Lyapunov exponents.

Targeted synchronization in an externally driven population of mechanical oscillators.

We experimentally investigate the synchronization of driven metronomes using a servo motor to impose external control. We show that a driven metronome will only synchronize in a narrow range near its own frequency; when we introduce coupling between metronomes, we can widen the range of frequencies over which a metronome will synchronize to the external input. Using these features, we design a signal to synchronize a population of dissimilar metronomes; separately we design a signal to selectively synchronize a subpopulation of metronomes within a heterogeneous population.

Symmetry effects on naturally arising chimera states in mechanical oscillator networks.

Coupled oscillators were believed to exclusively exist in a state of synchrony or disorder until Kuramoto theoretically proved that the two states could coexist, called a chimera state, when portions of the population had a spatial dependent coupling. Recent work has demonstrated the spontaneous emergence of chimera states in an experiment involving mechanical oscillators coupled through a two platform swing. We constructed an experimental apparatus with three platforms that each contains a population of mechanical oscillators in order investigate the effects of a network symmetry on naturally arising chimera states.

Heart failure is the strongest predictor of acute kidney injury in patients undergoing primary percutaneous coronary intervention for ST-elevation myocardial infarction.

Background: ST elevation myocardial infarction (STEMI) patients treated by primary percutaneous coronary intervention (PCI) are at higher risk of acute kidney injury (AKI) than patients undergoing PCI in stable clinical conditions. This fact suggests that mechanisms other than contrast nephrotoxicity are involved.

Aim: To evaluate the incidence, risk factors, and consequences of AKI in patients undergoing primary PCI for STEMI in current daily practice.

Clustering in delay-coupled smooth and relaxational chemical oscillators.

We investigate cluster synchronization in networks of nonlinear systems with time-delayed coupling. Using a generic model for a system close to the Hopf bifurcation, we predict the order of appearance of different cluster states and their corresponding common frequencies depending upon coupling delay. We may tune the delay time in order to ensure the existence and stability of a specific cluster state.

Concentrations of MMP-9 and TIMP-1 in lip tissue and their impact on cleft lip surgery healing.

Aim: To compare aspects of wound healing after cleft lip surgery performed within one week of age and wound healing after surgery performed within 2 - 4 months of age, especially concentrations of matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of metalloproteinases-1 (TIMP-1) in tissue removed during surgery.

Methods: 34 tissue samples (26 boys and 8 girls) were removed during surgery within one week of age (n=19) or within 2 - 4 months of age (n=15). Tissue samples were separated into epidermis, dermis and mucous membrane.

Reconstruction of two-dimensional phase dynamics from experiments on coupled oscillators.

Phase models are a powerful method to quantify the coupled dynamics of nonlinear oscillators from measured data. We use two phase modeling methods to quantify the dynamics of pairs of coupled electrochemical oscillators, based on the phases of the two oscillators independently and the phase difference, respectively. We discuss the benefits of the two-dimensional approach relative to the one-dimensional approach using phase difference.

[Catheter infection caused by Mycobacterium bovis].

Authors describe two cases of disseminated Mycobacterium bovis infection in two immunocompromised patients with central venous portcatheter. Diagnosis has been confirmed by cultivation from catether material. Antituberculotic treatment lead in the first case to clinical improvement and in the second case to clinical and radiological improvement.

Mobilization of mercury by DMPS in occupationally exposed workers and in model experiments on rats: evaluation of body burden.

The aim of the study was to evaluate the efficacy of DMPS (sodium-2,3-dimercapto-1-propane sulfonate) (Dimaval) administration for mobilizing mercury from the body in occupationally exposed people and experimental animals. Two doses of DMPS were administered at a 24-h interval to: (a) groups of people occupationally exposed to merkury--workers of the chloralkali industry (n = 43), and dentists (n = 12), (b) non-exposed individuals (n = 20), and (c) rats chronically exposed to mercury vapour at the concentration of 0.8 mg/m3 Hg degree (6 h/day, 5 days/week) for 15 weeks.

Biliary iron excretion in rats following treatment with analogs of pyridoxal isonicotinoyl hydrazone.

Iron overload is a major life-threatening complication of thalassemia major and other iron-loading anemias treated by regular blood transfusions. Although the clinical manifestations of iron overload may be prevented by desferrioxamine, the only iron-chelating drug in routine clinical use, this treatment requires subcutaneous infusion of desferrioxamine for 12 hours each day. New orally effective iron chelators are urgently needed, and pyridoxal isonicotinoyl hydrazone (PIH), which was first recognized as an effective iron chelator in vitro and subsequently in vivo, shows promise for the treatment of iron overload.

Biological monitoring of child lead exposure in the Czech Republic.

The area around the Pribram lead smelter has been recognized to be heavily contaminated by lead (Pb). In the early 1970s, several episodes of livestock lead intoxication were reported in this area; thereafter, several epidemiological and ecological studies focused on exposure of children. In contrast to earlier studies, the recent investigation (1992-1994) revealed significantly lower exposure to lead.

Exposure to lead and human health in the Czech Republic.

The aim of presented review is to address the most relevant issues related to the health effects caused by the human exposure to lead, as they have been recognized in Czech Republic in the period of 1992-1994 within the framework of the National Integrated Programme on Environment and Health (NIPEH) approved in 1992 and supported by WHO-European Centre for Environment and Health (WHO-ECEH), Bilthoven, The Netherlands and by the Government of the Netherlands. Basic sources of environment exposure to lead are identified and the fate of lead in the individual compartments of the environment is discussed. Relevant methods used for the exposure evaluation are summarized and the highest-risk group of population is defined.

Hazardous wastes in Eastern and Central Europe [meeting report].

The countries of Eastern and Central Europe have emerged from a political system which for decades has ignored protection of human health from hazardous wastes. While the economies of the countries in this region are stretched, awareness and concern about hazardous waste issues are a part of the new realities. At a recent conference sponsored in part by the National Institute of Environmental Health Sciences, representatives of seven countries in the region described the status of hazardous waste programs, issues of major concern, and steps being taken to protect human health.

[Motivation for preventive care].

This article outlines those psychological characteristics of preventive and prophylactic work that qualify it as an efficient and effective skill. The transactional analysis model is used for explaining some peculiarities of everyday contact and communication between medical professionals and patients.

In vivo and in vitro efficacy of a new carbodithioate for the mobilization of cadmium.

Female Wistar rats with chronic cadmium intoxication (oral exposure to low dosages of CdCl2 in drinking water over a period of 90 d) were used to examine the in vivo ability of a newly developed chelator, sodium N-(4-methylbenzyl)-4-O-(beta-D-galactopyranosyl)-D-glucamine-N- carbodithioate (MeBLDTC), singly and in combination with sodium 4-carboxy-amidopiperidine-N-carbodithioate (INADTC) as agents to induce the biliary and urinary excretion of cadmium. The combined administration of the two dithiocarbamates, which differ greatly in molecular weight and structural features, led to a synergistic increase in the biliary excretion of cadmium and an enhanced reduction of renal cadmium levels. The use of such a coadministration produced an increase in the biliary excretion of cadmium that was more than double that expected if the compounds acted in an additive fashion.

The NIPEH network of cooperating countries of central and eastern Europe. National Integrated Programmes on Environment and Health.

The National Integrated Programmes on Environment and Health (NIPEHs) in countries of Central and Eastern Europe (CCEE) are introduced. The NIPEH programme is one of the primary activities of the Bilthoven Division of the World Health Organization's European Centre for Environment and Health (WHO-ECEH). Located in the heart of the Netherlands on the compound of the Dutch National Institute of Public Health and Environmental Protection (RIVM) in Bilthoven, WHO-ECEH's Bilthoven Division has established a small but effective team of highly motivated experts who can draw upon the expertise available both within the Dutch host institution RIVM as well within the ECEH Centre of WHO-EURO.