We consider spiking neural P systems with rules allowed to introduce zero, one, or more spikes at the same time. The motivation comes both from constructing small universal systems and from generating strings; previous results from these areas are briefly recalled. Then, the computing power of the obtained systems is investigated, when considering them as number generating and as language generating devices. In the first case, a simpler proof of universality is obtained, while in the latter case we find characterizations of finite and recursively enumerable languages (without using any squeezing mechanism, as it was necessary in the case of standard rules). The relationships with regular languages are also investigated.

The crystallization of poly­(ε-caprolactone) (PCL) and isotactic polypropylene (iPP) infiltrated in nanoporous anodic alumina oxide (AAO) templates was reexamined to demonstrate the importance of obtaining polymer-free, clean AAO surfaces on the nucleation, size dependence of crystallization temperature (T c), and texture. The AAO pore diameters cover a broad range from 400 to 20 nm. When the AAO templates were completely free of any residual polymer on their surfaces, differential scanning calorimetry (DSC) experiments exhibited a single crystallization peak for all the samples with different AAO pore sizes. A drastic decrease in T c with density of domains indicated a transition from heterogeneous to homogeneous/surface nucleation. A regular decrease of T c with pore size was observed in the low T c regime, as a result of the volume dependence of nucleation events. The chain alignment of the two polymers infiltrated in AAO was studied by two-dimensional wide-angle X-ray scattering (WAXS). By comparing the experimental and simulated WAXS patterns, the orientation modes of the polymers were identified and compared with previous studies.