New insights into the electronic structure ofα-U andδ-Pu

This work presents the results of a theoretical study of the electronic structure of two actinide metals,α-U andδ-Pu. We compare ourab-initioresults obtained with the recently developed self-consistent Vertex corrected GW approach with previously published experimental measurements such as photo-electron spectroscopy, for the occupied density of states, and bremsstralung isochromat spectroscopy (BIS) and inverse photo-electron spectroscopy (IPES), for the unoccupied density of states. Ourab-initioapproach includes all important relativistic effects (it is based on Dirac's equation) and it represents the first application of the Vertex corrected GW approach in the physics of actinides. Overall, our theoretical results are in good agreement with the experimental data, which supports the level of approximations which our theoretical method is based upon. By comparing our vertex corrected GW results with our results obtained with less sophisticated approaches (local density approximation and self-consistent GW) we differentiate the strength of correlation effects in Uranium and Plutonium. Also, our theoretical results allow us to elucidate the subtle differences between the previously published experimental BIS and IPES data on the unoccupied density of states inα-U.

Positive non-linear capacitance: the origin of the steep subthreshold-slope in ferroelectric FETs

We show that the non-linear positive capacitance (PC) of ferroelectrics (FE) can explain the steep subthreshold-slope (SS) observed in FE based MOSFETs and often attributed to the existence of a negative capacitance in FE capacitors. Physically attainable and unattainable regions of the S-shape curve used in the negative capacitance theory are investigated by self-consistently solving Landau-Khalatnikov and Maxwell equations and by experimental validation. Finally, the conditions for attaining a steep SS in FE based MOSFETs assuming only positive capacitances are discussed.

Anhydrous Phase B: Transmission Electron Microscope Characterization and Elastic Properties

Anhydrous phase B and stishovite formed directly from olivine in experiments at 14 GPa and 1400 °CThe structure of anhydrous phase B is determined ab initio from precession electron diffraction tomography in transmission electron microscopyElastic and seismic properties of anhydrous phase B are calculated.

Design of a multi-well plate for high-throughput characterization of heterogeneous catalysts by XRD, FT-IR, Raman and XRF spectroscopies

For powder catalyst characterization, Fourier Transform Infrared (FTIR), Raman, and X-Ray Fluorescence (XRF) spectrometers and X-Ray Diffraction (XRD) are available in high-throughput (HT) configurations, for example at the REALCAT platform to sequentially analyse multiple sets of samples. To remove the bottleneck resulting from the use of different sample holders for each equipment, a unique multi-well plate was developed. This paper details the design of such a plate including the selection of the fabrication material and the plate dimensioning based on the study of the 4 different physical interactions between matter and electromagnetic radiations for the aforementioned techniques. This new plate consists of a holder for removable wells enabling the avoidance of cross-contamination between samples. Raman, a focusing technique, has no strict constraint on the plate design. The number of wells, their geometry, spacing and dimensions were adjusted to deal with the constraints of IR optics. The well depth was set according to the XRF maximum penetration depth in the sample. The well diameter was optimized in order to obtain from the X-ray spot size the maximum achievable intensity. Poly-methyl-methacrylate (PMMA) was chosen as the material for the new plate due to its amorphous structure (no peak in XRD analysis) and ease with which it can be cut by a laser. Finally, the flatness of the multi-well plate was validated on the most challenging instrument: XRD. This new plate allows fast sample filling/preparation, requires small quantities of catalyst (50 to 80 mg) in each well and is compatible and convenient for HT experimentation.

This paper presents a methodology to design a versatile, unique multi-well plate for high-throughput characterisation of heterogeneous catalyst by 4 different techniques (IR, Raman, XRF and XRD).

Synthesis and structural characterization of the first neptunium based metal–organic frameworks incorporating {Np6O8} hexanuclear clusters

The synthesis of the first transuranium Metal–Organic Frameworks (TRU-MOFs) is reported here.

Structural analysis of strained LaVO3 thin films

While structure refinement is routinely achieved for simple bulk materials, the accurate structural determination still poses challenges for thin films due on the one hand to the small amount of material deposited on the thicker substrate and, on the other hand, to the intricate epitaxial relationships that substantially complicate standard x-ray diffraction analysis. Using both electron and x-ray diffraction, we analyze the crystal structure of epitaxial LaVO3 thin films grown on (1 0 0)-oriented SrTiO3. Transmission electron microscopy study reveals that the thin films are epitaxially grown on SrTiO3 and points to the presence of 90° oriented domains. The mapping of the reciprocal space obtained by high resolution x-ray diffraction permits refinement of the lattice parameters. We finally deduce that strain accommodation imposes a monoclinic structure onto the LaVO3 film. The reciprocal space maps are numerically processed and the extracted data computed to refine the atomic positions, which are compared to those obtained using precession electron diffraction tomography.

[How to manage analysis and feedback of adverse events in transfusion]

Analysing adverse events is part of the medical practice in so far as the part it plays is outstanding in terms of feedback and improved healthcare safety. The integrated implementation of this practice is based on a four-dimensional system: strategic (corporate policies), cultural (safety-oriented cultural mindset), structural (dedicated organization and resources) and technical (methodologies and utilities). Two case studies illustrate the sequencing process from selecting the to-be-analyzed event down to figuring out the appropriate action plan. Beyond the visible and obvious origin, thanks to the implemented methods such as causal tree or ALARM method, far-fetched analysis elements and identified factors likely to explain events can be discovered. Comments on the role and terms of feedback are also hereto expressed.

The adsorption of ammonia on polycrystalline thorium

The chemistry of the actinides has long been an area of great interest to many researchers, due to the unusual nature of the f-orbital electrons. Electron spectroscopies provide a useful means to study the electronic structure of the 5f states, and how they affect the interactions of the actinide elements with various molecules. In this study the interaction of ammonia with a polycrystalline thorium surface at two different temperatures has been investigated using X-ray and ultraviolet photoelectron spectroscopic techniques. Exposure to ammonia at ambient temperature results in the formation of both nitride (Th-N) and NHx species, characterised by N1s photoemission peaks at 396.5 and 398.8 eV binding energy respectively, on the thorium surface. Exposure to ammonia at 100 K gives rise to an additional signal at 401.2 eV corresponding to physisorbed ammonia. Additional UPS results provided corroborating evidence for the effect of the surface temperature on the reaction with ammonia.

[How to analyze an incident of the transfusion chain]

Incidents and accidents analysis is one part of risk management in healthcare organisations. It is based on methods such as healthcare process analysis and the Association of Litigation and Risk Management (ALARM) method, to understand not only immediate causes but also root causes. The goal is to implement relevant remedial and preventive actions to secure healthcare processes. The hospital's risk management unit has to be involved in the methodological analysis of every grade zero transfusion incident. The system is based on a retrospective analysis process in compliance with the French National Authority for Health's ongoing requirements for risk reactive approach, allowing to identify failures and start relevant actions. Healthcare teams should overcome difficulties in order to be totally involved in the process. Human factors recognition, establishment of clear and effective communication between individuals and critical points of control should provide optimum quality care services that are safe and free of unnecessary risks.

Le programme national de depistage neonatal de la mucoviscidose mise en place et organisation

France has decided to add to the national neonatal screening program (Phenylketonuria, Hypothyroidism, Congenital Adrenal Hyperplasia, Sickle cell disease) the screening of cystic fibrosis (CF). The screening of CF will be implemented in all regions of France by the end of 2002 and will cover all newborn (near 800,000/year). Based on the recommendation of the French Screening Foundation, the project has been approved by the Health Ministry and will be financed by the social security. CF neonatal screening is now technically feasible and reliable. The proposed methodology includes: immunoreactive trypsin (IRT) dosage on all newborns at day 3 (by radioimmunology "Cis Bio" or immunofluorescence "Delfia") followed by genotype CFTR analysis if IRT level is above 60 micrograms/L. Screening for 29 mutations is planned. If genotype is negative, control of IRT at day 21 will be obtained. Several requirements are included in the program: a protocol of care for the newly diagnosed CF in a specialised CF center; information to all parents of newborns; results of CFTR genotype has to be given during a clinical visit, even if negative. This screening program should allow to screen 98% of the cystic fibrosis patients before the age of 1 month. In order to ensure perfect efficacy, the CF screening program will be evaluated and modified if necessary.

[To improve the quality of requisitions for radiologic examinations]

PURPOSE

This article presents the different steps implemented in order to improve the quality of requisitions for radiologic examinations in a hospital.

MATERIAL

and methods. The radiology requests sent from clinical units are periodically analyzed using criteria about tracking, prescription and security required for a good examination. Results are discussed with the clinical units in order to achieve improvements.

RESULTS

The periodical analysis of nonconformities shows a gradual improvement of practices. This action contributes to the realization of a single document for every request of examination or analysis in the hospital.

CONCLUSION

The described action is in the context of French regulations, first about the practice of radiology, second about the obligation of quality improvement that health care facilities now have to implement for their accreditation.

Influence of deep hypothermia on the tolerance of the isolated cardiomyocyte to ischemia-reperfusion

The influence of deep hypothermia (4 degrees C) during a substrate-free, hypoxia-reoxygenation treatment was investigated on cardiomyocytes (CM) prepared from newborn rat heart in culture in an in vitro, substrate-free model of ischemia-reperfusion. The transmembranous potentials were recorded with standard microelectrodes. The contractions were monitored photometrically. The RNA messenger (mRNA) and protein expression for protein (HSP70) were analysed by RT-PCR (reverse transcriptase-polymerase chain reaction) and Western blotting, respectively. Simulated ischemia (SI) caused a gradual decrease and then a cessation of the spontaneous electromechanical activity. During the reoxygenation, the CM recovered normal function, provided that SI did not exceed 2.5 h. When SI duration was increased up to 4 h, reoxygenation failed to restore the spontaneous electromechanical activity. Conversely, the exposure of the CM to SI together with deep hypothermia decreased the functional alterations observed, and provided a complete electromechanical recovery after 2.5 h as well as after 4 h of SI. Deep hypothermia alone failed to induce HSP70 mRNA and protein production. On the contrary, HSP70 mRNA production increased after 2.5 and 4 h of deep hypothermia followed by 1 h of rewarming, proportionally to the duration of the cooling period. This augmentation in mRNA was associated with a rise in HSP70 protein content. In summary, it appeared that deep hypothermia exerts a strong cytoprotective action during SI only, whereas cooling CM before SI has no beneficial effect on subsequent SI. Moreover, these results suggested the persistence of a signaling system and/or transduction in deeply cooled, functionally depressed cells. Finally, CM in culture appeared to be a model of interest for studying heart graft protection against ischemia-reperfusion and contributed to clarifying the molecular and cellular mechanisms of deep hypothermia on myocardium.