Highly luminescent scintillating hetero-ligand MOF nanocrystals with engineered Stokes shift for photonic applications.

Large Stokes shift fast emitters show a negligible reabsorption of their luminescence, a feature highly desirable for several applications such as fluorescence imaging, solar-light managing, and fabricating sensitive scintillating detectors for medical imaging and high-rate high-energy physics experiments. Here we obtain high efficiency luminescence with significant Stokes shift by exploiting fluorescent conjugated acene building blocks arranged in nanocrystals. Two ligands of equal molecular length and connectivity, yet complementary electronic properties, are co-assembled by zirconium oxy-hydroxy clusters, generating crystalline hetero-ligand metal-organic framework (MOF) nanocrystals. The diffusion of singlet excitons within the MOF and the matching of ligands absorption and emission properties enables an ultrafast activation of the low energy emission in the 100 ps time scale. The hybrid nanocrystals show a fluorescence quantum efficiency of ~60% and a Stokes shift as large as 750 meV (~6000 cm-1), which suppresses the emission reabsorption also in bulk devices. The fabricated prototypal nanocomposite fast scintillator shows benchmark performances which compete with those of some inorganic and organic commercial systems.

Fluorinated porous organic frameworks for improved CO2 and CH4 capture.

A porous 3D selectively fluorinated framework (F-PAF1), robust yet flexible and with a surface area of 2050 m2 g-1, was synthesised by condensation of an ad hoc prepared fluorinated tetraphenylmethane (TPM) monomer to ensure homogenously distributed C-F dipoles in the swellable architecture. Tetradentate TPM was also the comonomer for the reaction with fluorinated difunctional monomers to obtain frameworks (FMFs) with a controlled amount of regularly spaced reorientable C-F dipoles. The isosteric heat of adsorption of CO2 was increased by 53% by even moderate C-F dipole insertion, with respect to the non-fluorinated frameworks. CO2/N2 selectivity was also increased up to a value of 50 for the difluoro-containing comonomer. Moreover, methane shows optimal interaction energies of 24 kJ mol-1.

Expandable porous organic frameworks with built-in amino and hydroxyl functions for CO2 and CH4 capture.

The synthesis of porous organic 3D frameworks, wherein amine, hydroxyl and Li-alkoxide functions were built directly on the monomer-unit carbon core, realizes improved interactions with target gases. CO2 was retained by the amine group with a remarkable energy of 54 kJ mol-1, while 2D MAS NMR provided rare evidence of amine-to-gas short-distance interactions. Frameworks containing hydroxyl and Li-alkoxide functions show optimal interaction energies with CH4 of up to 25 kJ mol-1. The light network of 3-branch building units ensures the expandability of the nano-sponges.

[Epilepsy surgery in a reference centre]. / Cirugía de la epilepsia en un centro de referencia.

INTRODUCTION: Patients with drug resistant epilepsy are potential candidates for surgery. The pre surgical study of these patients involves a multidisciplinary approach. PATIENTS AND METHODS: We included patients who had been submitted to EEG video monitoring in our centre (a tertiary university hospital) between April 1995 and May 2000. The evaluation protocol included magnetic resonance (MR) brain scan (according to a specific protocol), neuropsychological and psychiatric evaluation, and ictal/interictal SPECT, when possible. Patients who underwent surgery were followed up at regular intervals until at least two years after surgery. RESULTS: Of the 299 patients with EEG video monitoring, 87 had been submitted to surgery up to June 2000. Nine of these patients required invasive subdural studies or studies of the foramen ovale using electrodes. Of the patients who underwent surgery, 44.8% had sclerosis of the hippocampus in the MR and in 10% it was found to be normal. The results of pathological anatomy revealed: 49.3% with sclerosis of the hippocampus, 15.1% with benign tumours, 13.7% with gliosis, 4.1% heterotopias and 4.1% cavernomas. Just one patient has been submitted to surgery again because of badly controlled seizures. Eight patients have presented post surgical complications (four with permanent morbidity). Of the 73 patients who were followed up for at least a year, 83.6% are in Engel class I, 9.6% in class II, 2.7% in class III and 4.1% in class IV. Among patients who underwent a temporal resection, 88.7% were in class I and 0% in class IV. CONCLUSIONS: Epilepsy surgery, in selected patients, has a very low morbidity/mortality rate and the chances that seizures will disappear or greatly improve are high.

[Nuclear medicine in Spain: high technology 2013]. / Medicina nuclear en España: alta tecnología 2013.

This article details the high technology equipment in Spain obtained through a survey sent to the three main provider companies of equipment installed in Spain. The geographical distribution of high technology by Autonomous Communities and its antiquity have been analyzed.