The Climate change discussion and rising energy prices have resulted in an increase in the literature on the causal relationship between energy use and economic growth. In addition, there are also new developments in econometrics, most of all the use of panel unit root and cointegration techniques. However those techniques have not been applied in comparative studies covering the European electricity markets so far. The empirical investigation of the causality relationship between electricity demand and income for 15 European countries between 1978 and 2005 involves three steps. First, the order of integration is determined by applying standard ADF and panel unit root testing procedures. Second, cointegration techniques are performed in order to test for the long-run relationship between the variables in question. Finally, the existence and direction of causality in the short-and long-run will be assessed for each country by using vector error correction models and Granger causality tests. a see [3] and [4]

Presently, one of the greatest challenges of humankind is climate change. It is usually assumed that its mitigation will require an extensive adaptation in many human habits. As every fourth ton of carbon dioxide emitted can be attributed to the food chain, it is argued that one of the most effective actions an individual can take is changing towards a more sustainable diet, like a plant-based one. Serious games have proved to be a successful means for achieving behavior change. We present Veganity, your journey, a mobile serious game aimed at assisting players in their transition towards a more plantbased diet. The game combines the characteristics of the idle game genre with diet tracking: in the game, as you progress in adapting your personal diet, you spare energy that can be spent in making the game world more sustainable. Personal factors, like changing your ecological or social norms, your habits and your behavioral costs and benefits, are targeted by different game mechanics. These include, among others, a currency mechanism for stimulating habit change, in-game actions building up selfefficacy, and tips raising problem awareness. Besides describing our game design, we also present the main features of the game implementation. From a preliminary evaluation, we conclude that Veganity, your journey successfully engages players in pursuing their own diet goals, and increases their reflection on, and acquaintance with, sustainable diet behaviors.

The 2019 Mazurian Lakes Conference on Physics was held in Piaski, a vacation resort located at the lake of Bełdany in the heart of the Great Mazurian Lakes District, from the 1 st to 7 th of September 2019. It was the 36 th meeting in a series initiated over 50 years ago, in 1968, by Professor Zdzisław Wilhelmi and his students and collaborators. Throughout these years, the Mazurian conferences have gained a worldwide reputation for their high scientific merit and a unique atmosphere. The 36 th meeting