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411.
We show that the intelligence of a swarm of cooperative units (birds) emerges at criticality, as an effect of the joint action of frequent organizational collapses and of spatial correlation as extended as the flock size. The organizational collapses make the birds become independent of one another, thereby allowing the flock to follow the direction of the lookout birds. Long-range correlation violates the principle of locality, making the lookout birds transmit information on either danger or resources with a time delay determined by the time distance between two consecutive collapses. 相似文献
412.
Marcello Seri Marco Lenci Mirko degli Esposti Giampaolo Cristadoro 《Journal of statistical physics》2011,144(1):124-138
We consider the billiard dynamics in a non-compact set of ℝ
d
that is constructed as a bi-infinite chain of translated copies of the same d-dimensional polytope. A random configuration of semi-dispersing scatterers is placed in each copy. The ensemble of dynamical
systems thus defined, one for each global realization of the scatterers, is called quenched random Lorentz tube. Under some fairly general conditions, we prove that every system in the ensemble is hyperbolic and almost every system is
recurrent, ergodic, and enjoys some higher chaotic properties. 相似文献
413.
We show that for every ɛ > 0 there is a set A ⊂ ℝ3 such that H
1 ⌞A is a monotone measure, the corresponding tangent measures at the origin are non-conical and non-unique and H
1 ⌞A has the 1-dimensional density between 1 and 2+ɛ everywhere in the support. 相似文献
414.
Bege N Renette T Jansch M Reul R Merkel O Petersen H Curdy C Müller RH Kissel T 《Macromolecular bioscience》2011,11(7):897-904
The goal of this study was to investigate the suitability of poly(ethylene carbonate) (PEC) nanoparticles as a novel drug delivery system, fulfilling the requirements for a long circulation time. Particles were obtained with a narrow size distribution and nearly neutral zeta potential. Adsorption studies with human plasma proteins revealed that PEC nanoparticles bind much less proteins in comparison to polystyrene (PS) nanoparticles. Cell experiments with fluorescently labeled PEC showed no uptake of the nanoparticles by macrophages. These novel PEC nanospheres with their unique surface properties are a promising candidate for long circulating drug delivery systems in vivo. 相似文献
415.
Bezić N Vuko E Dunkić V Ruščić M Blažević I Burčul F 《Molecules (Basel, Switzerland)》2011,16(9):8119-8129
The purpose of this study was to compare the essential oil profiles of four Croatian Teucrium species (Lamiaceae), as determined by GC and GC/MS, with their antiphytoviral efficiency. A phytochemical analysis showed that T. polium, T. flavum, T. montanum and T. chamaedrys are characterized by similar essential oil compositions. The investigated oils are characterized by a high proportion of the sesquiterpene hydrocarbons β-caryophyllene (7.1-52.0%) and germacrene D (8.7-17.0%). Other important components were β-pinene from T. montanum and α-pinene from T. flavum. The investigated essential oils were proved to reduce lesion number in the local host Chenopodium quinoa Willd. infected with Cucumber Mosaic Virus (CMV), with reductions of 41.4%, 22.9%, 44.3% and 25.7%, respectively. 相似文献
416.
Andrej Gajduk Mirko Todorovski Ljupco Kocarev 《The European physical journal. Special topics》2014,223(12):2387-2409
Transient stability and steady-state (small signal) stability in power girds are reviewed. Transient stability concepts are illustrated with simple examples; in particular, we consider three methods for computing region of attraction: time-simulations, extended Lyapunov function, and sum of squares optimization method. We discuss steady state stability in power systems, and present an example of a feedback control via a communication network for the 10?Unit 39 Bus New England Test system. 相似文献
417.
Mirko Horňák Stanislav Jendrol′ Ingo Schiermeyer Roman Soták 《Journal of Graph Theory》2015,78(4):248-257
In the article, the existence of rainbow cycles in edge colored plane triangulations is studied. It is shown that the minimum number of colors that force the existence of a rainbow C3 in any n‐vertex plane triangulation is equal to . For a lower bound and for an upper bound of the number is determined. 相似文献
418.
Tomáš Homola Jindřich Matoušek Martin Kormunda Linda Y. L. Wu Mirko Černák 《Plasma Chemistry and Plasma Processing》2013,33(5):881-894
We report a study on the treatment of flat glass surfaces by ambient air atmospheric pressure plasma, generated by a dielectric barrier discharge of coplanar arrangement of the electrode system—the diffuse coplanar surface barrier discharge (DCSBD). The plasma treatment of glass was performed in both static and dynamic modes. With respect to wettability of the glass surface, treatment in static mode resulted in non-uniform surface properties, whereas dynamic mode provided a fully uniform treatment. A water contact angle measurement was used to determine the efficiency of plasma treatments in dynamic mode and also to investigate a hydrophobic recovery of plasma treated glass surfaces. The X-ray photoelectron spectroscopy measurements showed a decrease of overall carbon concentrations after plasma treatment. A deconvolution of C1s peak, showed that a short plasma treatment led to decrease of C–C bonds concentration and increases of C–O and O–C=O bond concentrations. An enhancing influence of the glass surface itself on DCSBD diffuse plasma was observed and explained by different discharge onsets and changes in the electric field distribution. 相似文献
419.
Analysis of genomic methylation level using micellar electrokinetic chromatography with UV detection
Alessio Ferrone Mirko Pesce Sara Franceschelli Lorenza Speranza Maria Anna De Lutiis Alfredo Grilli Mario Felaco Antonia Patruno 《Electrophoresis》2013,34(15):2275-2280
Analytical methods for quantification of 5′‐methylcytosine in genomes are important tools to investigate epigenetic changes in gene expression during development, differentiation, aging, or cancer. Here, we report a novel genomic methylation content assay based on enzymatic hydrolysis of DNA and MEKC separation of 5′‐deoxyribonucleoside monophosphates (dNMP) using the cationic surfactant CTAB as pseudostationary phase. Calf Thymus DNA was used during method development to determine electrophoretic parameters and electrolyte composition for a complete separation between 2′‐deoxycytosine‐5′‐monophosphate and 2′‐deoxy‐5′‐methylcytosine 5′‐monophosphate (d5mCMP). Methylated and not methylated oligonucleotides were used to confirm the identity of each peak and evaluate analytical parameters of the method. The LOD of the method was found to be 12.5 pmol/μL for d5mCMP. 相似文献
420.
In modern society, sewage is disposed of in a two-step process: it is first made into granules and the sewage sludge granules are then burned in an appropriate com-bustor. The present paper describes a spouted bed cas-cade system for sewage sludge combustion developed at the Technical University of Berlin at the turn of the present century. Combustion results in the recovery of the com-bustible matters of the sewage in the form of thermal en-ergy. Fig. 1 illustrates the three main stages invo… 相似文献