Cancer development can be viewed as an example of spatio-temporal pattern formation. Several attempts have been made to model and predict malignant tumor behavior and also to account for immune system response and the impact of possible clinical treatments. Modeling started from a macroscopic perspective and developed towards cell-based approaches, from which cellular automaton (CA) models are an example. In this article, we first introduce the general concept of CA systems. Then, we review CA models of tumor development, focusing on avascular and vascular growth, tumor invasion and angiogenesis. Finally, a comparative analysis of the models as well as criteria for designing new CA models are provided and future perspectives are outlined.

Highly ordered TiO2 nanotubes (NTs) were synthesized by electrochemical anodization of Ti foils. We investigated the effect of the Ti surface roughness (applying different pretreatments prior to the anodization) on the length, growth rate and degree of selforganization of the obtained NT arrays. The mechanisms related to the TiO2 NT formation and growth were correlated not only with the corresponding anodization curves but also with their appropriate derivatives (1 st order) and suitable integrated and/or obtained parameters, to reveal the onset and end of different electrochemical regimes. This enables an in-depth interpretation (and physical-chemical insight), for different levels of surface roughness and topographic features. We found that pretreatments lead to an extremely small Ti surface roughness, offer an enhanced NT length and also provide a significant improvement in the template organization quality (highly ordered hexagonal NT arrays over larger areas), due to the optimized surface topography. We present a new statistical approach for evaluating highly ordered hexagonal NT array areas. Large domains with ideally arranged nanotube structures represented by a hexagonal closely packed array were obtained (6.61 m 2 ), close to the smallest grain diameter of the Ti foil and three times larger than those so far reported in the literature. The use of optimized pre-treatments then allowed avoiding a second anodization step, ultimately leading to highly hexagonal self-ordered samples with large organized domains at reduced time and cost.

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A series of thirteen xanthones 3–15 was prepared based on substitutional (appendage) diversity reactions. The series was structurally characterized based on their spectral data and HRMS, and the structures of xanthone derivatives 1, 7, and 8 were determined by single-crystal X-ray diffraction. This series, along with an in-house series of aminated xanthones 16–33, was tested for in-vitro antimicrobial activity against seven bacterial (including two multidrug-resistant) strains and five fungal strains. 1-(Dibromomethyl)-3,4-dimethoxy-9H-xanthen-9-one (7) and 1-(dibromomethyl)-3,4,6-trimethoxy-9H-xanthen-9-one (8) exhibited antibacterial activity against all tested strains. In addition, 3,4-dihydroxy-1-methyl-9H-xanthen-9-one (3) revealed a potent inhibitory effect on the growth of dermatophyte clinical strains (T. rubrum FF5, M. canis FF1 and E. floccosum FF9), with a MIC of 16 µg/mL for all the tested strains. Compounds 3 and 26 showed a potent inhibitory effect on two C. albicans virulence factors: germ tube and biofilm formation.

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High resolution electrical resistivity measurements ( rho d rho /dT) are used to investigate in detail the two spin-reorientation transitions of the hexagonal ferromagnetic NdCo5 compound which occur at TSR1=242 K and TSR2=283 K (T>TSR2 gives spontaneous magnetisation, Ms, parallel to the c axis; TSR1