The quantity and quality of scientific output of the topmost 50 countries in the four basic sciences (agricultural & biological sciences, chemistry, mathematics, and physics & astronomy) are studied in the period of the recent 12 years (1996 -2007). In order to rank the countries, a novel two-dimensional method is proposed, which is inspired by the H-index and other methods based on quality and quantity measures. The countries data are represented in a "quantity-quality diagram", and partitioned by a conventional statistical algorithm (k-means), into three clusters, members of which are rather the same in all of the basic sciences. The results offer a new perspective on the global positions of countries with regards to their scientific output.

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The Abelian Sandpile Model (ASM) is a paradigm of self-organized criticality (SOC) which is related to c = −2 conformal field theory. The conformal fields corresponding to some height clusters have been suggested before. Here we derive the first corrections to such fields, in a field theoretical approach, when the lattice parameter is non-vanishing and consider them in the presence of a boundary.

The relative positions of country groups in the world of science are studied via application of a two-dimensional mapping method that is based on quantity and quality indicators of the scientific production as peer-reviewed articles. To obtain such indicators, different influential effects such as the background global trends, temporal fluctuations, disciplinary characteristics, and mainly, the effect of countries resources have been taken into account. Fifty countries with the highest scientific production are studied in 12 years (1996-2007). A common clustering algorithm is used to detect groups of co-evolving countries in the two-dimensional map, and thereby countries are classified into four major groups based on their relative positions in the map. The final results are contrasted with a non-resource-scaled map by considering some exemplary countries that have drastically different positions in the two maps.

Rotation induced by uniform and non-uniform magnetic fields in a conducting fluid carrying an electric current Shirsavar, R.; Nasiri, M.; Amjadi, A.; Nejati, A.; Sobhani, S.O.; Habibi, M.