Introduction Le diabète est, de par la gravité de ses complications et sa progression épidémique, un enjeu de santé publique. La place de l’hospitalisation reste cependant floue dans les ...recommandations. Le but de ce travail est d’étudier les possibilités d’utilisation du PMSI dans l’analyse de la prise en charge du diabète en endocrinologie et du parcours de soins des personnes diabétiques à l’AP-HP, afin d’améliorer la connaissance des pratiques. Matériels et méthodes Les séjours des services spécialisés en endocrinologie, dia-bétologie ou nutrition adulte de l’AP-HP en 2013 ont été extraits du PMSI. Puis, les séjours pour diabète en 2012 à l’AP-HP, tous services confondus, ont été repérés. Grâce au chaînage des données, les informations sur les réhospitalisations de ces personnes à l’AP-HP pendant 1 an ont été recueillies. Résultats La prise en charge du diabète à l’AP-HP dans les services spécialisés représente 50 % de l’activité totale en 2013, et a majoritairement lieu (51 %) en hôpital de jour. Les personnes hospitalisées au moins une fois pour diabète en 2012, tous services confondus, ont en majorité (78 %) un diabète de type 2, et 57 ans en moyenne. Elles ont plus d’une hospitalisation dans l’année dans 39 % des cas, avec 5 journées cumulées d’hospitalisation, dont 3 pour diabète (35 journées cumulées, dont 22 pour diabète, s’il existe au moins une hospitalisation pour pied diabétique). Près de 11 % des personnes hospitalisées présentent une vulnérabilité sociale. Conclusion Il est donc possible de caractériser l’activité d’une spécialité médicale et le parcours des personnes hospitalisées à l’AP-HP à l’aide des données du PMSI. Ce travail constitue un support à disposition des médecins, afin d’aider à la réflexion sur l’évolution des prises en charge. Déclaration d’intérêt Les auteurs déclarent ne pas avoir d’intérêt direct ou indirect (financier ou en nature) avec un organisme privé, industriel ou commercial en relation avec le sujet présenté.
Electron paramagnetic resonance (EPR) spectroscopy interrogates unpaired electron spins in solids and liquids to reveal local structure and dynamics; for example, EPR has elucidated parts of the ...structure of protein complexes that other techniques in structural biology have not been able to reveal. EPR can also probe the interplay of light and electricity in organic solar cells and light-emitting diodes, and the origin of decoherence in condensed matter, which is of fundamental importance to the development of quantum information processors. Like nuclear magnetic resonance, EPR spectroscopy becomes more powerful at high magnetic fields and frequencies, and with excitation by coherent pulses rather than continuous waves. However, the difficulty of generating sequences of powerful pulses at frequencies above 100 gigahertz has, until now, confined high-power pulsed EPR to magnetic fields of 3.5 teslas and below. Here we demonstrate that one-kilowatt pulses from a free-electron laser can power a pulsed EPR spectrometer at 240 gigahertz (8.5 teslas), providing transformative enhancements over the alternative, a state-of-the-art ∼30-milliwatt solid-state source. Our spectrometer can rotate spin-1/2 electrons through π/2 in only 6 nanoseconds (compared to 300 nanoseconds with the solid-state source). Fourier-transform EPR on nitrogen impurities in diamond demonstrates excitation and detection of EPR lines separated by about 200 megahertz. We measured decoherence times as short as 63 nanoseconds, in a frozen solution of nitroxide free-radicals at temperatures as high as 190 kelvin. Both free-electron lasers and the quasi-optical technology developed for the spectrometer are scalable to frequencies well in excess of one terahertz, opening the way to high-power pulsed EPR spectroscopy up to the highest static magnetic fields currently available.
We report the determination of the Dzyaloshinsky-Moriya interaction, the dominant magnetic anisotropy term in the kagome spin-1/2 compound ZnCu3(OH)6Cl2. Based on the analysis of the high-temperature ...electron spin resonance (ESR) spectra, we find its main component |Dz|=15(1) K to be perpendicular to the kagome planes. Through the temperature dependent ESR linewidth, we observe a building up of nearest-neighbor spin-spin correlations below approximately 150 K.
Pulsed electrically detected magnetic resonance of phosphorous (31P) in bulk crystalline silicon at very high magnetic fields (B0>8.5 T) and low temperatures (T=2.8 K) is presented. We find that the ...spin-dependent capture and reemission of highly polarized (>95%) conduction electrons by equally highly polarized 31P donor electrons introduces less decoherence than other mechanisms for spin-to-charge conversion. This allows the electrical detection of spin coherence times in excess of 100 mus, 50 times longer than the previous maximum for electrically detected spin readout experiments.
Background Older companion dogs naturally develop a dementia-like syndrome with biological, clinical and therapeutic similarities to Alzheimer disease (AD). Given there has been no new safe, ...clinically effective and widely accessible treatment for AD for almost 20 years, an all-new cell therapeutic approach was trialled in canine veterinary patients, and further modelled in aged rats for more detailed neurobiological analysis. Methods A Phase 1/2A veterinary trial was conducted in N = 6 older companion dogs with definitive diagnosis of Canine Cognitive Dysfunction (CCD). Treatment comprised direct microinjection of 250,000 autologous skin-derived neuroprecursors (SKNs) into the bilateral hippocampus using MRI-guided stereotaxis. Safety was assessed clinically and efficacy using the validated Canine Cognitive Dysfunction Rating Scale (CCDR) at baseline and 3-month post treatment. Intention to treat analysis imputed a single patient that had a surgical adverse event requiring euthanasia. Three dog brains were donated following natural death and histology carried out to quantify Alzheimer pathology as well as immature neurons and synapses; these were compared to a brain bank (N = 12) of untreated aged dogs with and without CCD. Further, an age-related memory dysfunction rat model (N = 16) was used to more closely evaluate intrahippocampal engraftment of canine SKN cells, focusing on mnemonic and synaptic effects as well as donor cell survival, neurodifferentation and electrophysiologic circuit integration in a live hippocampal slice preparation. Results Four out-of-five dogs improved on the primary clinical CCDR endpoint, three fell below diagnostic threshold, and remarkably, two underwent full syndromal reversal lasting up to 2 years. At post mortem, synaptic density in the hippocampus specifically was nine standard deviations above non-treated dogs, and intensity of new neurons also several fold higher. There was no impact on AD pathology or long-term safety signals. Modelling in aged rats replicated the main canine trial findings: hippocampally-dependent place memory deficits were reversed and synaptic depletion rescued. In addition, this model confirmed donor cell survival and migration throughout the hippocampus, neuronal differentiation in situ, and physiologically-correct integration into pyramidal layer circuits. Conclusions With further development, SKN cell therapy may have potential for treating carefully chosen AD patients based on neurosynaptic restoration in the hippocampus. Keywords: Alzheimer's disease, Dementia, Hippocampus, Cell therapy, Stem cells, Neural precursors, Canine, Rodent
When performed using an exhaustive search, the maximum likelihood (ML) joint detection of all users in a multicarrier code-division multiple-access (MC-CDMA) system has a prohibitive complexity, ...growing exponentially with the number of users and the number of bits in each modulation symbol. In this paper, a novel ML multiuser detection algorithm is proposed, the complexity of which is a polynomial function of the number of users and is independent of the modulation size. The MC-CDMA system is modeled as a sphere packing lattice and a low-complexity optimum lattice decoder, the sphere decoder, is applied to jointly detect all users. Suboptimum simplifications, based on the orthogonal projection of the received signal on a facet of the lattice constellation, are also proposed to further decrease the complexity. Simulation results are shown with up to 64 users transmitting 16-quadrature-amplitude modulation symbols.
We report methodology that combines an ultrawide band multifrequency microwave system with technology of high magnetic fields for solving challenging problems in electron magnetic resonance (EMR) ...spectroscopy. This strategy has been made possible due to a novel EMR facility operating in an exceptionally wide range of microwave frequencies of 24 GHz to 3 THz, at magnetic fields up to 17 T, and in the temperature range of 1.6 to 330 K. The basic configuration of the multifrequency system works in a transmission mode and employs oversized cylindrical waveguides for routing the microwave power. A wide-band, low-noise, liquid helium cooled (4.2 K) InSb bolometer is used for signal detection. This approach results in an extremely wide-band performance, thus making it possible to employ a variety of solid-state millimeter and submillimeter microwave sources in combination with a far infrared laser microwave source for performing multifrequency EMR experiments. A complexity of resonant structures and related technical problems such as microphonics at high magnetic fields is virtually eliminated. The system is simple, yet sensitive, and has been revealed to be extremely advantageous while solving such problems as observation of AFMR transitions in spin-ordered systems, g-factor resolution enhancement in complex organic radicals, and resonance signal detection in EMR-silent spin systems having integer spin and large zero field splitting. A technical description of the multifrequency high-field EMR facility is presented and results of its performance tests are given. The potential utility of using the multifrequency high-field methodology in EMR studies is illustrated with selected examples of its recent applications.
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