Schlaf und Nachtfluglärm: subjektive Wirkungen der Kernruhezeit am Frankfurter Flughafen im Längsschnittvergleich

Im Rahmen des Forschungsverbundprojekts NORAH untersuchte das DLR Institut für Luft- und Raumfahrtmedizin im Modul „Auswirkungen von Fluglärm auf den nächtlichen Schlaf“ in drei Messkampagnen die subjektiven Wirkungen des Fluglärms auf den Schlaf vor und nach Eröffnung der Landebahn Nordwest am Frankfurter Flughafen im Oktober 2011 und der damit einhergehenden Kernruhezeit von 23 bis 5 Uhr. Die Studien wurden im Auftrag des Umwelt- und Nachbarschaftshauses im Forum Flughafen und Region (FFR) erstellt. Sie wurden mit insgesamt 202 Probanden zu Hause im durch Nachtfluglärm belasteten Rhein-Main Gebiet durchgeführt. Die subjektiven Wirkungen des nächtlichen Fluglärms vor und nach Einführung der Kernruhezeit wurden durch Einschätzungen der schlafbezogenen psychologischen Parameter „Schlafdauer“, „Schlaftiefe“ und „Schlaferholung“ mit visuellen Analogskalen (VAS) erfasst. Als weitere Indikatoren einer durch Fluglärm schlafgestörten Nacht dienten Müdigkeits- und Schläfrigkeitsbewertungen morgens nach dem Aufstehen mittels eines Fatigue-Fragebogens (FAT) und der Karolinska Sleepiness Scale (KSS). Für alle subjektiven Variablen wurden Expositions-Wirkungskurven in Abhängigkeit vom energieäquivalenten fluglärmbezogenen Dauerschallpegel LAeq sowie der Anzahl an nächtlichen Überfluggeräuschen mittels logistischer Regression mit Zufallseffekt berechnet. Nicht-akustische Moderatoren und das Studienjahr wurden bei der Modellbildung berücksichtigt. Im Längsschnittvergleich zeigt sich für die Schlaftiefe und Schlaferholung sowie die Müdigkeit und Schläfrigkeit eine statistisch signifikante Zunahme im dreijährigen Studienverlauf, was einer Verschlechterung des Schlaferlebens der Anwohner entspricht. Danach hat die Einführung der Kernruhezeit am Frankfurter Flughafen subjektiv zu keiner statistisch signifikanten Verbesserung des Schlafs im Vergleich zur Basiserhebung im Jahr 2011 mit durchgängigem Nachtflugbetrieb geführt. Dieses Ergebnis ist allerdings unabhängig von der Fluglärmbelastung und auf den Einfluss nicht erhobener Parameter zurückzuführen

A fluorescent polarization-based assay for the identification of disruptors of the RCAN1/calcineurin A protein complex

5 pages, 4 figures, a table. 19891949 [PubMed]Calcineurin is a Ca(2+)/calmodulin-dependent serine/threonine protein phosphatase involved in many biological processes and developmental programs, including immune response. One of the most studied substrates of calcineurin is the transcription factor NFAT (nuclear factor of activated T cells) responsible for T-cell activation. Different anticalcineurin drugs, such as cyclosporine A and FK506, are the most commonly used immunosuppressants in transplantation therapies. Unfortunately, their mechanism of action, completely blocking the calcineurin phosphatase activity while also requiring continuous administration, bears severe side effects. During recent years, the family of regulators of calcineurin (RCAN) has been described and studied extensively as modulators of calcineurin signaling pathways. The RCAN1 region, spanning amino acids 198 to 218 and responsible for inhibiting the calcineurin-NFAT signaling pathway in vivo, has been identified. An RCAN1-derived peptide spanning this sequence interferes with the calcineurin-NFAT interaction without affecting the general calcineurin phosphatase activity. Here we report the development of an optimized in vitro high-throughput fluorescence polarization assay based on the disruption of the RCAN1(198-218)-CnA interaction for identifying molecules with immunosuppressant potential. This approach led us to identify dipyridamole as a disruptor of such interaction. Moreover, three small molecules with a potential immunosuppressive effect were also identifiedThis work was supported by grants from Fundació La Marató de TV3 (Ref. 030830), the Spanish Ministry of Education and Science (SAF2006-04815, BIO2004-00998, BIO2007-60066, CTQ2005-00995/BQU), the Fundación Mutua Madrileña 2007 and from the Generalitat de Catalunya (Ref. 2006 BE 00051)Peer reviewe

Comments on Sweeny and Gliozzi dynamics for simulations of Potts models in the Fortuin-Kasteleyn representation

We compare the correlation times of the Sweeny and Gliozzi dynamics for two-dimensional Ising and three-state Potts models, and the three-dimensional Ising model for the simulations in the percolation prepresentation. The results are also compared with Swendsen-Wang and Wolff cluster dynamics. It is found that Sweeny and Gliozzi dynamics have essentially the same dynamical critical behavior. Contrary to Gliozzi's claim (cond-mat/0201285), the Gliozzi dynamics has critical slowing down comparable to that of other cluster methods. For the two-dimensional Ising model, both Sweeny and Gliozzi dynamics give good fits to logarithmic size dependences; for two-dimensional three-state Potts model, their dynamical critical exponent z is 0.49(1); the three-dimensional Ising model has z = 0.37(2).Comment: RevTeX, 4 pages, 5 figure

Numerical simulations of current generation and dynamo excitation in a mechanically-forced, turbulent flow

The role of turbulence in current generation and self-excitation of magnetic fields has been studied in the geometry of a mechanically driven, spherical dynamo experiment, using a three dimensional numerical computation. A simple impeller model drives a flow which can generate a growing magnetic field, depending upon the magnetic Reynolds number, Rm, and the fluid Reynolds number. When the flow is laminar, the dynamo transition is governed by a simple threshold in Rm, above which a growing magnetic eigenmode is observed. The eigenmode is primarily a dipole field tranverse to axis of symmetry of the flow. In saturation the Lorentz force slows the flow such that the magnetic eigenmode becomes marginally stable. For turbulent flow, the dynamo eigenmode is suppressed. The mechanism of suppression is due to a combination of a time varying large-scale field and the presence of fluctuation driven currents which effectively enhance the magnetic diffusivity. For higher Rm a dynamo reappears, however the structure of the magnetic field is often different from the laminar dynamo; it is dominated by a dipolar magnetic field which is aligned with the axis of symmetry of the mean-flow, apparently generated by fluctuation-driven currents. The fluctuation-driven currents have been studied by applying a weak magnetic field to laminar and turbulent flows. The magnetic fields generated by the fluctuations are significant: a dipole moment aligned with the symmetry axis of the mean-flow is generated similar to those observed in the experiment, and both toroidal and poloidal flux expulsion are observed.Comment: 14 pages, 14 figure

Random RNA under tension

The Laessig-Wiese (LW) field theory for the freezing transition of random RNA secondary structures is generalized to the situation of an external force. We find a second-order phase transition at a critical applied force f = f_c. For f f_c, the extension L as a function of pulling force f scales as (f-f_c)^(1/gamma-1). The exponent gamma is calculated in an epsilon-expansion: At 1-loop order gamma = epsilon/2 = 1/2, equivalent to the disorder-free case. 2-loop results yielding gamma = 0.6 are briefly mentioned. Using a locking argument, we speculate that this result extends to the strong-disorder phase.Comment: 6 pages, 10 figures. v2: corrected typos, discussion on locking argument improve

Residents’ negative attitude towards air traffic is associated with impaired objective sleep quality

Objectives: Nocturnal aircraft noise induces sleep disturbances and is associated with impaired quality of life. The magnitude of physiological and psychological responses to noise varies among individuals. Stable individual vulnerabilities have been reported for aircraft noise induced awakenings. To date it is unknown, whether the subjective attitude towards air traffic and residents' sleep quality impact on each other. Methods: Seventy-four out of 81 investigated residents around Frankfurt Airport (Germany) rated their attitude towards air traffic (from 1 = negative to 5 = positive; negative attitude: score ≤ 2, N=28, mean age 44 ± 16 years; moderate to positive attitude: score > 3, N=46, mean age 44 ± 15 years) and evaluated its necessity (from 1 = not necessary to 5 = highly necessary; no to moderate necessity: score ≤ 3, N=22, mean age 45 ± 10 years; high necessity: score > 3, N=52, mean age 43 ± 17 years). In addition, polysomnographical recordings were obtained in residents' home environment. These investigations were part of the NORAH sleep study in 2012. Results: Significant impairments in sleep quality (prolonged sleep onset latency, increased wake after sleep onset, reduced sleep efficiency, and less deep sleep) were found for participants with a negative attitude towards air traffic. The judgement of no or moderate necessity of air traffic was associated with a significantly reduced deep sleep duration. Conclusions: Residents' subjective attitude towards air traffic and their objective sleep quality are related. Cause and effect in this relationship remain to be identified

Reactions at polymer interfaces: A Monte Carlo Simulation

Reactions at a strongly segregated interface of a symmetric binary polymer blend are investigated via Monte Carlo simulations. End functionalized homopolymers of different species interact at the interface instantaneously and irreversibly to form diblock copolymers. The simulations, in the framework of the bond fluctuation model, determine the time dependence of the copolymer production in the initial and intermediate time regime for small reactant concentration $\rho_0 R_g^3=0.163 ... 0.0406$. The results are compared to recent theories and simulation data of a simple reaction diffusion model. For the reactant concentration accessible in the simulation, no linear growth of the copolymer density is found in the initial regime, and a $\sqrt{t}$-law is observed in the intermediate stage.Comment: to appear in Macromolecule

SrCu_2(BO_3)_2 - a Two Dimensional Spin Liquid

We study an extended Shastry-Sutherland model for SrCu_2(BO_3)_2 and analyze the low lying parts of the energy spectrum by means of a perturbative unitary transformation based on flow equations. The derivation of the 1-magnon dispersion (elementary triplets) is discussed. Additionally, we give a quantitative description (symmetries and energies) of bound states made from two elementary triplets. Our high order results allow to fix the model parameters for SrCu_2(BO_3)_2 precisely: J_1=6.16(10)meV, x:=J_2/J_1=0.603(3), J_\perp=1.3(2)meV. To our knowledge this is the first quantitative treatment of bound states in a true 2d model.Comment: 4 pages, 3 figures, Proceeding paper of the HFM2000 conference in Waterloo, Canada, Jun 200