Passive dispersal of the grape rust mite Calepitrimerus vitis Nalepa 1905 (Acari, Eriophyoidea) in vineyards

Modes of passive dispersal of the grape rust mite Calepitrimerus vitis (Eriophyoidea) were investigated in a vineyard of South-Western Germany. More than 200 Eriophyoidea per month were trapped in a wind chamber during summer (32,1 % C. vitis) suggesting long-distance dispersal by air currents. Rain washed part of the adult C. vitis population from the foliage. SE micrographs suggest that quiescent nymphs are affixed to the leaf by a substance of unknown nature. However, the role of rain in C. vitis colonisation of uninfested vineyards is still unclear, as is the role of phoretic transport by arthropods. For the first time, evidence of rust mite dispersal by human activity is presented. A large number of C. vitis was found adhering to clothes and hands of workers carrying out customary cultural practices in the vineyard. Other arthropods, including Typhlodromus pyri, the main predator of C. vitis, were also passively transported by wind, rain and human activit

Universal scaling behavior at the upper critical dimension of non-equilibrium continuous phase transitions

In this work we analyze the universal scaling functions and the critical exponents at the upper critical dimension of a continuous phase transition. The consideration of the universal scaling behavior yields a decisive check of the value of the upper critical dimension. We apply our method to a non-equilibrium continuous phase transition. But focusing on the equation of state of the phase transition it is easy to extend our analysis to all equilibrium and non-equilibrium phase transitions observed numerically or experimentally.Comment: 4 pages, 3 figure

Shear-induced reaction-limited aggregation kinetics of Brownian particles at arbitrary concentrations

The aggregation of interacting Brownian particles in sheared concentrated suspensions is an important issue in colloid and soft matter science per se. Also, it serves as a model to understand biochemical reactions occurring in vivo where both crowding and shear play an important role. We present an effective medium approach within the Smoluchowski equation with shear which allows one to calculate the encounter kinetics through a potential barrier under shear at arbitrary colloid concentrations. Experiments on a model colloidal system in simple shear flow support the validity of the model in the range considered. By generalizing Kramers' rate theory to the presence of collective hydrodynamics, our model explains the significant increase in the shear-induced reaction-limited aggregation kinetics upon increasing the colloid concentration

The liquid to vapor phase transition in excited nuclei

For many years it has been speculated that excited nuclei would undergo a liquid to vapor phase transition. For even longer, it has been known that clusterization in a vapor carries direct information on the liquid- vapor equilibrium according to Fisher's droplet model. Now the thermal component of the 8 GeV/c pion + 197Au multifragmentation data of the ISiS Collaboration is shown to follow the scaling predicted by Fisher's model, thus providing the strongest evidence yet of the liquid to vapor phase transition.Comment: four pages, four figures, first two in color (corrected typo in Ref. [26], corrected error in Fig. 4

Spin-transfer in an open ferromagnetic layer: from negative damping to effective temperature

Spin-transfer is a typical spintronics effect that allows a ferromagnetic layer to be switched by spin-injection. Most of the experimental results about spin transfer are described on the basis of the Landau-Lifshitz-Gilbert equation of the magnetization, in which additional current-dependent damping factors are added, and can be positive or negative. The origin of the damping can be investigated further by performing stochastic experiments, like one shot relaxation experiments under spin-injection in the activation regime of the magnetization. In this regime, the N\'eel-Brown activation law is observed which leads to the introduction of a current-dependent effective temperature. In order to justify the introduction of these counterintuitive parameters (effective temperature and negative damping), a detailed thermokinetic analysis of the different sub-systems involved is performed. We propose a thermokinetic description of the different forms of energy exchanged between the electric and the ferromagnetic sub-systems at a Normal/Ferromagnetic junction. The corresponding Fokker Planck equations, including relaxations, are derived. The damping coefficients are studied in terms of Onsager-Casimir transport coefficients, with the help of the reciprocity relations. The effective temperature is deduced in the activation regime.Comment: 65 pages, 10 figure

Application of the Wagner-Nelson absorption method to the two-compartment open model

This report considers the application of the Wagner- Nelson method to both one- and two- compartment open model data when there is no competing reaction at the absorption site. Equations are derived which show that application of the Wagner- Nelson method to data which obey the twocompartment open model with first-order absorption allows accurate estimation of not only the rate constant k a but also the parameters of the two- compartment open model, namely k 12 , k 21 , and k el . In the example given, this new method was more accurate than the classical “feathering” or ”back- projection” method. The appropriate criterion for “collapsing” the two- to the onecompartment open model is given. In cases where the one-compartment open model applies, and absorption is first order but abruptly ceases after some time, it is shown that k a may be accurately estimated by application of the Guggenheim method to the A T /V values calculated for the absorption phase.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45046/1/10928_2005_Article_BF01070942.pd

Probability Theory Compatible with the New Conception of Modern Thermodynamics. Economics and Crisis of Debts

We show that G\"odel's negative results concerning arithmetic, which date back to the 1930s, and the ancient "sand pile" paradox (known also as "sorites paradox") pose the questions of the use of fuzzy sets and of the effect of a measuring device on the experiment. The consideration of these facts led, in thermodynamics, to a new one-parameter family of ideal gases. In turn, this leads to a new approach to probability theory (including the new notion of independent events). As applied to economics, this gives the correction, based on Friedman's rule, to Irving Fisher's "Main Law of Economics" and enables us to consider the theory of debt crisis.Comment: 48p., 14 figs., 82 refs.; more precise mathematical explanations are added. arXiv admin note: significant text overlap with arXiv:1111.610

Ninth and Tenth Order Virial Coefficients for Hard Spheres in D Dimensions

We evaluate the virial coefficients B_k for k<=10 for hard spheres in dimensions D=2,...,8. Virial coefficients with k even are found to be negative when D>=5. This provides strong evidence that the leading singularity for the virial series lies away from the positive real axis when D>=5. Further analysis provides evidence that negative virial coefficients will be seen for some k>10 for D=4, and there is a distinct possibility that negative virial coefficients will also eventually occur for D=3.Comment: 33 pages, 12 figure

A genome-wide association study for corneal curvature identifies the platelet-derived growth factor receptor alpha gene as a quantitative trait locus for eye size in white Europeans

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