Probenecid and benzamide: DSC applied to the study of an “impossible” pharmaceutical system

Journal of Thermal Analysis and Calorimetry - The study of the binary system probenecid–benzamide is an excellent example of the power and the limits of thermal analysis applied to the...     

Novel silica stabilization method for the analysis of fine nanocrystals using coherent X‐ray diffraction imaging

High‐energy X‐ray Bragg coherent diffraction imaging (BCDI) is a well established synchrotron‐based technique used to quantitatively reconstruct the three‐dimensional morphology and strain distribution in nanocrystals. The BCDI technique has become a powerful analytical tool for quantitative investigations of nanocrystals, nanotubes, nanorods and more recently biological systems. BCDI has however typically failed for fine nanocrystals in sub‐100 nm size regimes – a size routinely achievable by chemical synthesis – despite the spatial resolution of the BCDI technique being 20–30 nm. The limitations of this technique arise from the movement of nanocrystals under illumination by the highly coherent beam, which prevents full diffraction data sets from being acquired. A solution is provided here to overcome this problem and extend the size limit of the BCDI technique, through the design of a novel stabilization method by embedding the fine nanocrystals into a silica matrix. Chemically synthesized FePt nanocrystals of maximum dimension 20 nm and AuPd nanocrystals in the size range 60–65 nm were investigated with BCDI measurement at beamline 34‐ID‐C of the APS, Argonne National Laboratory. Novel experimental methodologies to elucidate the presence of strain in fine nanocrystals are a necessary pre‐requisite in order to better understand strain profiles in engineered nanocrystals for novel device development.     

Dynamical entropy production in spiking neuron networks in the balanced state

We demonstrate deterministic extensive chaos in the dynamics of large sparse networks of theta neurons in the balanced state. The analysis is based on numerically exact calculations of the full spectrum of Lyapunov exponents, the entropy production rate, and the attractor dimension. Extensive chaos is found in inhibitory networks and becomes more intense when an excitatory population is included. We find a strikingly high rate of entropy production that would limit information representation in cortical spike patterns to the immediate stimulus response.     

Probenecid and benzamide: cocrystal prepared by a green method and its physico-chemical and pharmaceutical characterization

Journal of Thermal Analysis and Calorimetry - The eco-friendly method of kneading was here used to synthesize a cocrystal of probenecid, an uricosuric drug used in treating gout and hyperuricemia,...