Physical origin underlying the entropy loss upon hydrophobic hydration

The hydrophobic effect (HE) is commonly associated with the demixing of oil and water at ambient conditions and plays the leading role in determining the structure and stability of biomolecular assembly in aqueous solutions. On the molecular scale HE has an entropic origin. It is believed that hydrophobic particles induce order in the surrounding water by reducing the volume of con- figuration space available for hydrogen bonding. Here we show with computer simulation results that this traditional picture is not correct. Analyzing collective fluctuations in water clusters we are able to provide a fundamentally new picture of HE based on pronounced many-body correlations affecting the switching of hydrogen bonds between molecules. These correlations emerge as a non-local compensation of reduced fluctuations of local electrostatic fields in the presence of an apolar solute

Reform of Financing of Municipalities in Slovenia

The article presents a comparison of the Slovenian Financing of Municipalities Act, which had been in force since April 20062, and the new act, which entered into force on 1st January 20072.The main question asked is how the changed formula for calculating the appropriate expenditure and the capitation introduced affect the financing of municipalities. The primary hypothesis is that the change introduced would positively affect the share of own revenues in the appropriate expenditure of the majority of municipalities, that the influence of financial equalisation would decrease and that the financial independence of municipalities would increase. Concurrently, the extent of municipal financial surpluses that have not been regulatory treated until this change would decrease. The results, presented in this article, confirm the suggested hypothesis that was proven by past data and a simulation of the new situation.appropriate expenditure, financial equalisation, capitation, municipality diversity index surplus, Slovenia.

Waldschmidt constants for Stanley-Reisner ideals of a class of Simplicial Complexes

We study the symbolic powers of the Stanley-Reisner ideal $I_{B_n}$ of a bipyramid $B_n$ over a $n-$gon $Q_n$. Using a combinatorial approach, based on analysis of subtrees in $Q_n$ we compute the Waldschmidt constant of $I_{B_n}$.Comment: 10 pages, 2 figure

On Financial Markets Trading

Starting from the observation of the real trading activity, we propose a model of a stockmarket simulating all the typical phases taking place in a stock exchange. We show that there is no need of several classes of agents once one has introduced realistic constraints in order to confine money, time, gain and loss within an appropriate range. The main ingredients are local and global coupling, randomness, Zipf distribution of resources and price formation when inserting an order. The simulation starts with the initial public offer and comprises the broadcasting of news/advertisements and the building of the book, where all the selling and buying orders are stored. The model is able to reproduce fat tails and clustered volatility, the two most significant characteristics of a real stockmarket, being driven by very intuitive parameters.Comment: 18 pages, submitte

The use of artificial neural networks in adiabatic curves modeling

Adiabatic hydration curves are the most suitable data for temperature calculations in concrete hardening structures. However, it is very difficult to predict the adiabatic hydration curve of an arbitrary concrete mixture. The idea of modeling adiabatic temperature rise during concrete hydration with the use of artificial neural networks was introduced in order to describe the adiabatic hydration of an arbitrary concrete mixture, depending on factors which influence the hydration process of cement in concrete. The influence of these factors was determined by our own experiments. A comparison between experimentally determined adiabatic curves and adiabatic curves, evaluated by proposed numerical model shows that artificial neural networks can be used to predict adiabatic hydration curves effectively. This model can be easily incorporated in the computer programs for prediction of the thermal fields in young concrete structures, implemented in the finite element or finite difference codes. New adiabatic hydration curves with some other initial parameters of the concrete mixture can be easily included in this model in order to expand the range of suitability of artificial neural networks to predict the adiabatic hydration curves. (C) 2008 Elsevier B.V. All rights reserved