Transition et rétablissement

Cet article présente les risques liés aux transitians de soins et en particulier hospitalo-ambulatoires, qui, sans mesure d'accompagnement proactive, menacent le processus de rétablissement des personnes souffrant de troubles psychiatriques. En effet, les risques de rupture des soins et de réadmission sont davantage liés aux caractéristiques du système sociosanitaire qu'à celles du patient ou de la maladie. Des mesures d'accompagnement simples ne sont pas systématiques dans le domaine de la psychiatrie, alors même que ces patients sont particulièrement vulnérables dans les périodes de post-hospitalisation souvent synonymes de barrières au traitement. Le modèle de case management de transition développé à Lausanne est brièvement présenté et illustré au moyen d'une vignette clinique. Ses particularités sont notamment le recours systématique à certains outils soutenant le rétablissement et l'implication active du patient et de son entourage depuis l'hospitalisation jusqu'au retour dans la communauté.

The activation process of the alpha1B-adrenergic receptor: potential role of protonation and hydrophobicity of a highly conserved aspartate.

In this study, a quantitative approach was used to investigate the role of D142, which belongs to the highly conserved E/DRY sequence, in the activation process of the alpha1B-adrenergic receptor (alpha1B-AR). Experimental and computer-simulated mutagenesis were performed by substituting all possible natural amino acids at the D142 site. The resulting congeneric set of proteins together with the finding that all the receptor mutants show various levels of constitutive (agonist-independent) activity enabled us to quantitatively analyze the relationships between structural/dynamic features and the extent of constitutive activity. Our results suggest that the hydrophobic/hydrophilic character of D142, which could be regulated by protonation/deprotonation of this residue, is an important modulator of the transition between the inactive (R) and active (R*) state of the alpha1B-AR. Our study represents an example of quantitative structure-activity relationship analysis of the activation process of a G protein-coupled receptor.

X-ray diffraction, thermal analysis, and Raman scattering study of K2BeF4 and comparation to other member of the (beta)-K2SO4 family with ferroelectric -paraelectric transition

Thermal analysis, powder diffraction, and Raman scattering as a function of the temperature were carried out on K2BeF4. Moreover, the crystal structure was determined at 293 K from powder diffraction. The compound shows a transition from Pna21 to Pnam space group at 921 K with a transition enthalpy of 5 kJ/mol. The transition is assumed to be first order because the compound shows metastability. Structurally and spectroscopically the transition is similar to those observed in (NH4)2SO4, which suggests that the low-temperature phase is ferroelectric. In order to confirm it, the spontaneous polarization has been computed using an ionic model.

Recherche de l'iridium à la limite Permien-Trias du site de Meishan, Changhsing (R. P. Chine).

La forte teneur en elements siderophiles des sediments de la limite Cretace-Tertiaire suggere que les principaJes disparitions d'especes ont ete provoquees par des catastrophes cosmiques. Cette hypothese pourrait etre confirmee par la decouverte d'une anomaJie similaire it la limite Permien-Trias, caracterisee par la plus grave crise biologique du Phanerozoique. L'etude du site de Meishan, en Republique populaire de Chine, n'apporte aucune confirmation de ce scenario. Aucune trace d'iridium, Ie meilleur traceur de la matiere extraterrestre, n'a ete trouvee dans les 18 echantillons preleves au voisinage de la transition Permien-Trias. Toute relation entre la crise biologique du Permien-Trias et une catastrophe cosmique doit donc, pour l'instant, etre consideree comme hypothetique. The presence of siderophile-enriched material at the Cretaceous-Tertiary boundary suggests that the major extinctions of living species could result from cosmic catastrophes. The finding of the same kind of material at the Permian-Triassic boundary would be important to confirm the influence of cosmic phenomena on extinctions. The study of the M eishan section, in China, does not provide any support to this view. Iridium, the best tracer of cosmic material, has not been detected in any of the 18 samples collected around the boundary. A relation between the Permian-Triassic extinction and a cosmic collision therefore remains hypothetical.

Geochemical changes at the Permian-Triassic transition in Southern Alps and adjacent area: a review

Compilation of the recent literature from the Southern Alps and adjacent area confirms the geochemical variations of unusual amplitudes during the Permian-Triassic boundary interval (PTBI). A great attention has been given to the negative δ13C anomaly within the Tesero Member close to the Permian-Triassic boundary. Very detailed geochemical works have been done on the scientific Gartnerkofel core (Gk-1) and on the Slovenian sections. Major minor and rare earth elements (REE) data are reported and show a marked enrichment in alkaline metals and REE of some levels of the boundary interval. But recent studies show that the low Iridium anomalies and the Osmium and Helium isotopes anomalies lack the characteristics of a large extraterrestrial impact.

Impedance field and transition from thermal to shot noise in Cd1-xZnxTe semi-insulating Ohmic detectors

Within a drift-diffusion model we investigate the role of the self-consistent electric field in determining the impedance field of a macroscopic Ohmic (linear) resistor made by a compensated semi-insulating semiconductor at arbitrary values of the applied voltage. The presence of long-range Coulomb correlations is found to be responsible for a reshaping of the spatial profile of the impedance field. This reshaping gives a null contribution to the macroscopic impedance but modifies essentially the transition from thermal to shot noise of a macroscopic linear resistor. Theoretical calculations explain a set of noise experiments carried out in semi-insulating CdZnTe detectors.

Effects of Nb doping on the TiO2 anatase-to-rutile phase transition

We study the influence of Nb doping on the TiO2 anatase-to-rutile phase transition, using combined transmission electron microscopy, Raman spectroscopy, x-ray diffraction and selected area electron diffraction analysis. This approach enabled anatase-to-rutile phase transition hindering to be clearly observed for low Nb-doped TiO2 samples. Moreover, there was clear grain growth inhibition in the samples containing Nb. The use of high resolution transmission electron microscopy with our samples provides an innovative perspective compared with previous research on this issue. Our analysis shows that niobium is segregated from the anatase structure before and during the phase transformation, leading to the formation of NbO nanoclusters on the surface of the TiO2 rutile nanoparticles.

Rebuild Iowa Office Transition Strategy

The Rebuild Iowa Transition Strategy has been drafted to provide a comprehensive set of recommended action steps to help the state complete long-term recovery efforts while better preparing the state for future disasters. This report begins with a review of the 12 major Rebuild Iowa Advisory Commission (RIAC) recommendations which have guided RIO’s work, followed by a summary of the major accomplishments toward each recommendation. The identification of remaining needs and issues serves as the basis for the transition strategy. The following outlines the action steps necessary to achieve a successful transition and recovery.

Avalanches in a fluctuationless first-order phase transition in a random-bond Ising model

We study the behavior of the random-bond Ising model at zero temperature by numerical simulations for a variable amount of disorder. The model is an example of systems exhibiting a fluctuationless first-order phase transition similar to some field-induced phase transitions in ferromagnetic systems and the martensitic phase transition appearing in a number of metallic alloys. We focus on the study of the hysteresis cycles appearing when the external field is swept from positive to negative values. By using a finite-size scaling hypothesis, we analyze the disorder-induced phase transition between the phase exhibiting a discontinuity in the hysteresis cycle and the phase with the continuous hysteresis cycle. Critical exponents characterizing the transition are obtained. We also analyze the size and duration distributions of the magnetization jumps (avalanches).

Vibrational behaviour of bcc Cu-based shape memory alloys close to the martensitic transition

Experimental data from ultrasonic and inelastic neutron scattering measurements are analyzed for different families of Cu-based shape-memory alloys. It is shown that the transition occurs at a value, independent of composition and alloy family, of the ratio between the elastic constants associated with the two shears necessary to accomplish the lattice distortion from the bcc to the close-packed structure. The zone boundary frequency of the TA2[110] branch evaluated at the transition point (TM), weakly depends, for each family, on composition. A linear relationship between this frequency and the inverse of the elastic constant C', both quantities evaluated at TM, has been found, in agreement with the prediction of a Landau model proposed for martensitic transformations.