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Protein adsorption studies returned to the focus of medical therapeutics, when it was found that up to 2500 non-plasma proteins adsorbed to hip implants during arthroplastic surgery, challenging peri-implant healing models. Questions have re-emerged as to the implications of uncontrolled protein unfolding after adsorption. In past studies on the cooperativity of protein binding we discovered protein adsorption hysteresis, a thermodynamically irreversible process. The present precursory study comprises real-time kinetic (TIRF-Rheometry) and equilibrium (125I-tracer ) studies on the hysteretic binding of fibrinogen and rhBMP-2 to titanium and glass surfaces via transient states. Thermodynamic constants (GOn), as well as kinetically derived (K'A ) and hysteresis derived (K'HA ) association constants in the range of 106 to 1012 M-1lead to a consistent picture.

In this publication the effect of the operating temperature on the effective inductance of a controllable inductor is analysed. The main difference compared to a coil with a simple single core lies in the current-controlled inductance-value. This is achieved by a second core implemented perpendicular upon the load-toroid affecting the saturation within a limited shared volume. Corresponding to the presented analysis, the dependencies on the core temperatures are investigated by measurements. [ABSTRACT FROM AUTHOR]

Byline: Axel Muller (1,2), Johannes Schweizer (1,2), Michael Meissner (2), Daniela Winkler (1,2), Gunther Voigt (2) Keywords: Akuter Myokardinfarkt; Herzinfarktregister; Primar rekanalisierende Therapie; Thrombolyse; Medikamentose Therapie; 28-Tage-Krankenhausletalitat; Acute myocardial infarction; Myocardial infarction registry; Reperfusion therapy; Thrombolysis; Medication; 28-day hospital mortality Abstract (German): Im Rahmen des Forschungsprojektes aHerzinfarktregister Chemnitz 2000' wurden 1999 in Chemnitz epidemiologische und klinische Daten bei Patienten mit akutem Myokardinfarkt erhoben. Einbezogen wurde die uber 25-jahrige Bevolkerung der Stadt Chemnitz. Die Erfassung der Daten erfolgte retrospektiv in Anlehnung an das WHO-MONICA-Projekt. Insgesamt wurden im Jahr 1999 Daten von 2798 Fallen in das Herzinfarktregister aufgenommen. 355 Patienten (12,7%) wurden mit einem definitiven (MD 1) und 453 (16,2%) mit einem moglichen Myokardinfarkt (MD 2) erfasst. 29 Patienten (1,0%) hatten einen ischamischen Herzstillstand (MD 3) und bei 56 Patienten (2,0%) bestanden ungenugende Angaben (MD 9). 1905 Patienten (68,1%) wurden der Diagnosekategorie MD 4 -- kein Myokardinfarkt -- zugeordnet. Die Ereignisraten fur den definitiven (MD 1) und bestatigten (MD 1 und 2) stiegen mit zunehmendem Alter deutlich an und waren bei Mannern hoher als bei Frauen. 1999 erhielten 23,3% der Patienten eine primar rekanalisierende Therapie (Thrombolyse oder akute PTCA). Im Vergleich zu 1984 und 1994 konnte in der Altersgruppe der 25- bis 64-Jahrigen der Anteil der Patienten mit primar rekanalisierender Therapie stetig erhoht werden. Fur die Patienten mit definitivem Myokardinfarkt wurde eine 28-Tage-Krankenhausletalitat von 16,7% ermittelt. Trotz methodischer Probleme sind Herzinfarktregister wichtige Instrumente zum Vergleich epidemiologischer und klinischer Daten uber einen definierten Zeitraum sowie zwischen verschiedenen Erfassungszentren und zur Uberprufung der medizinischen Behandlung. Abstract: Epidemiological and clinical data from patients with acute myocardial infarction were obtained for the 'Myocardial Infarction Registry Chemnitz 2000' project in Chemnitz in 1999. People aged 25 years and older living in Chemnitz were included in the project. The case search had to be done retrospectively in accordance with the WHO MONICA Project. In 1999, 2,798 patients were registered. Three hundred fifty-five patients (12.7%) had definitive (MD 1) and 453 patients (16.2%) possible myocardial infarction (MD 2) 29 patients (1.0%) had an ischemic cardiac arrest (MD 3), 1,905 patients (68.1%) had no myocardial infarction (MD 4), and for 56 patients (2.0) the data base was not sufficient (MD 9). The event rates for the definitive (MD 1) and confirmed myocardial infarction (MD 1 and 2) were higher in men that in women and increased with age. In 1999, 23.3% of patients with definitive myocardial infarction were treated with reperfusion therapy (thrombolysis or acute percutaneous transluminal coronary angioplasty, PTCA). The numbers of patients aged 25--64 years with myocardial infarction who received reperfusion therapy increased continuously from 1984 to 1999 in Chemnitz. In the patients with definitive myocardial infarction, a 28-day hospital mortality rate of 16.7% was detected. Despite methodological problems, myocardial infarction registries are important tools for comparisons of epidemiological and clinical data for a definitive period and between different centers. The myocardial infarction registries are also useful instruments for control of medical treatment. Author Affiliation: (1) Klinik fur Innere Medizin I, Krankenhaus Kuchwald der Klinikum Chemnitz GmbH, Burgerstrasse 2, 09113, Chemnitz (2) Arbeitsgruppe Praventivmedizin und Epidemiologie in Chemnitz e.V. Article History: Registration Date: 05/03/2004 Received Date: 14/04/2003 Accepted Date: 13/06/2003 Online Date: 06/05/2004

Noise generated by motion of charge and spin provides a unique window into materials at the atomic scale. From temperature of resistors to electrons breaking into fractional quasiparticles, "listening" to the noise spectrum is a powerful way to decode underlying dynamics. Here, we use ultrasensitive superconducting quantum interference device (SQUIDs) to probe the puzzling noise in a frustrated magnet, the spin-ice compound Dy2Ti2O7 (DTO), revealing cooperative and memory effects. DTO is a topological magnet in three dimensions--characterized by emergent magnetostatics and telltale fractionalized magnetic monopole quasiparticles--whose real-time dynamical properties have been an enigma from the very beginning. We show that DTO exhibits highly anomalous noise spectra, differing significantly from the expected Brownian noise of monopole random walks, in three qualitatively different regimes: equilibrium spin ice, a "frozen" regime extending to ultralow temperatures, and a high-temperature "anomalous" paramagnet. We present several distinct mechanisms that give rise to varied colored noise spectra. In addition, we identify the structure of the local spin-flip dynamics as a crucial ingredient for any modeling. Thus, the dynamics of spin ice reflects the interplay of local dynamics with emergent topological degrees of freedom and a frustration-generated imperfectly flat energy landscape, and as such, it points to intriguing cooperative and memory effects for a broad class of magnetic materials. [ABSTRACT FROM AUTHOR]

Abstract Background Particle Swarm Optimization (PSO) is an established method for parameter optimization. It represents a population-based adaptive optimization technique that is influenced by several "strategy parameters". Choosing reasonable parameter values for the PSO is crucial for its convergence behavior, and depends on the optimization task. We present a method for parameter meta-optimization based on PSO and its application to neural network training. The concept of the Optimized Particle Swarm Optimization (OPSO) is to optimize the free parameters of the PSO by having swarms within a swarm. We assessed the performance of the OPSO method on a set of five artificial fitness functions and compared it to the performance of two popular PSO implementations. Results Our results indicate that PSO performance can be improved if meta-optimized parameter sets are applied. In addition, we could improve optimization speed and quality on the other PSO methods in the majority of our experiments. We applied the OPSO method to neural network training with the aim to build a quantitative model for predicting blood-brain barrier permeation of small organic molecules. On average, training time decreased by a factor of four and two in comparison to the other PSO methods, respectively. By applying the OPSO method, a prediction model showing good correlation with training-, test- and validation data was obtained. Conclusion Optimizing the free parameters of the PSO method can result in performance gain. The OPSO approach yields parameter combinations improving overall optimization performance. Its conceptual simplicity makes implementing the method a straightforward task.

The SREP is a holistic assessment of a credit institution s business model, governance risks to capital and to liquidity. It is based on a common methodology combining quantitative and qualitative elements with a forward-looking perspective. Completion of the SREP of r each supervised bank is a major task of the European Central Bank (ECB) in the Single Supervisory Mechanism (SSM). This article analyses the SREP and first experiences with this process. [ABSTRACT FROM AUTHOR]