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We present a rock slope instability hazardstudy of the Flône pit (Belgium) by means ofa deterministic kinematic stability analysis.Thespecificity of this study resides in the“digital augmentation” of the field mappingstructural database (x 5) by semi-automaticpoint cloud analysis. Results show that themain instability hazards in the actual pitare flexural toppling and, to a lesser extent,wedge sliding. Planar sliding, althoughminor, will constitute a significant hazardfor interbench ruptureduringfutureexcavationdue to the presence of an anticlinestructure at depth. The augmented - andgeoreferenced - structural database hasenabled us to generate a synthetic rockslope instability hazard map that constitutes the basis for the recommendation oftargeted monitoring solutions during futureexcavation works.

The overproduction of free radicals and oxygen reactive species is suspected to be implicated in a wide range of metabolic reactions that can have pernicious consequences in the development of a variety of human diseases. Botanical extracts are sources of antioxidants that counteract both free radicals and oxygen reactive species. The processing conditions used in the botanical extraction may influence the antioxidant composition; therefore, different extracts from the same plant may have different antioxidant properties. To illustrate this fact, we conducted a study using three commercial rosemary (Rosmarinus officinalis L.) leaf extracts. The three extracts were standardized to contain, respectively, 20% carnosic acid, 40% ursolic acid, or 20% rosmarinic acid. They were evaluated for their total (hydrophilic + lipophilic) antioxidant effects on oxygen radical absorbance capacity (ORAC), their ferric reducing/antioxidant power (FRAP), and their capacity to inhibit Cu(2+)-induced low-density lipoprotein (LDL) oxidation ex vivo. The ursolic acid extract showed the lowest antioxidant capacity on all models. The rosmarinic acid extract had an antioxidant capacity 1.5 times higher on ORAC and four times higher on FRAP than the carnosic acid extract. However, the carnosic acid extract was better than the rosmarinic acid extract in inhibiting the oxidation of LDL ex vivo. These results encourage conducting further studies to evaluate the carnosic acid and rosmarinic acid extracts in vivo. Our study offers an example of the importance of the extraction procedures, on which depends the nature of the antioxidant composition, and highlights interest to proceed with in vitro/ex vivo assay selection for the evaluation of the antioxidant properties of botanical extracts.

Mafic xenoliths, sometimes interlayered with magmatic peridotites, are abundant in the scoria cones of Puy Beaunit in the French Massif Central. These are mainly layered gabbronorites with some norites, pyroxenites and anorthosites; they probably derive from a Permian differentiated deep layered intrusion. Crystallisation conditions were estimated at about 1000°C and 1 GPa. The rocks underwent sub-solidus re-equilibration at about 770°C and 1 GPa (isobaric cooling) in the lowermost crust. Two distinct symplectitic textures (pyroxene-plagioclase-spinel intergrowths) have been observed; they result from the destabilization of magmatic garnet (750-800°C, 0.55-0.8 GPa) and amphibole (990°C

The Puy Beaunit volcano vent, French Massif Central, displays a population of plutonic mafic to ultramafic xenoliths, commonly showing asymmetric, millimetre to centimetre thick, layering. Layers are pyroxenitic to gabbroic, and less commonly peridotitic (lherzolite, dunite, websterite) and anorthositic. These xenoliths are interpreted as samples of a layered intrusion, located at the crust-mantle boundary. Primary cumulate phases are olivine and orthopyroxene, followed by clinopyroxene and plagioclase; rare intercumulus accessory phases (apatite, rutile and zircon) are observed in the most differentiated layers. Homogeneous xenoliths, interpreted as single cumulate layers, have a calc-alkaline geochemistry with LREE and large ion lithophile elements (LILE) enrichments relative to Nb, Ta and Ti. The negative Eu anomaly of pyroxenite can be related to earlier plagioclase fractionation, as observed in the gabbroic layers. Trace element laser ablation inductively coupled plasma emission mass spectrometry (LA-ICP-MS) and secondary ion mass spectrometry (SIMS) analyses of plagioclase, orthopyroxene and zircon from layered rocks suggest equilibrium and cogenetic relations between the silicate phases. U-Pb SIMS dating of a 1.5 mm zircon crystal gives a magmatic or sub-solidus equilibration age of 257 ± 6 Ma. The Beaunit layered intrusion belongs to the large Permian within-plate magmatic episode commonly of calc-alkaline geochemical signature observed over Europe and North Africa. It probably corresponds to a mafic underplating event spatially controlled by post-Variscan trans-tensional to trans-pressional basin tectonics in an intracontinental setting. The subduction-related geochemical signature of the magmatic suite is interpreted as resulting from the passive remobilisation of a mantle source, which was previously metasomatised during the Variscan subduction. © 2003 Elsevier Science B.V. All rights reserved.

BACKGROUND Calculated plasma (Cp) and calculated effect site concentrations (Ce) of propofol associated with loss of consciousness (LOC) have been studied in young healthy patients. The aim of the study was to evaluate the calculated propofol concentrations required to induce LOC in ASA III adult patients undergoing cardiac surgery using a smooth target controlled infusion of propofol. METHODS After informed consent, 44 patients were premedicated with 0.5 mg alprazolam orally. Propofol TCI using the pharmacokinetic set of Marsh et al. incorporated in the Diprifusor (ThalfKeo of 2.6 min) was used. Propofol Ce was progressively increased by 0.5 micro g/ml until LOC was obtained. The constraint on the maximum gradient between Cp and Ce was either 1 micro g/ml in group 1 or not limited in group 2. Hemodynamic variations were assessed. RESULTS Mean preoperative left ventricular ejection fractions were 44 +/- 15.4% and 56 +/- 11.4% in groups 1 and 2, respectively (P < 0.01). At LOC, mean Cp was 1.9 micro g/ml in both groups but mean Ce was 1.08 +/- 0.31 and 1.43 +/- 0.42 micro g/ml in groups 1 and 2, respectively (P < 0.01). The mean induction time was 12.8 +/- 7.1 min in group 1 and 8.5 +/- 2.7 min in group 2 (P < 0.05). No episode of hypotension has been observed in either group. CONCLUSION In ASA III patients undergoing cardiac surgery, smooth propofol TCI induction, using the pharmacokinetic set of Marsh et al. incorporated in the Diprifusor, is associated with LOC at a low mean calculated plasma concentration of 1.9 micro g/ml and good hemodynamic stability.

This paper shortly describes an Infusion Toolbox and a blood pressure (BP) control application. It explains how we applied an agent model and client-server technology to integrate them. We show that by using this framework and object oriented technologies the necessary changes to the existing applications are reduced. Many elements of the tested original systems could be re-used, which enhances safe development.

Experiments were performed on rabbits randomly assigned to intracisternally receive 0.3 mL of plain bupivacaine 5 mg/mL, liposomal bupivacaine 5 mg/mL, bupivacaine-free liposomes or isotonic phosphate- buffered saline. Mechanical ventilation was initiated or intravenous dopamine was infused when respiratory depression or hypotension occurred. Seven days after the injection, the whole spinal cord was removed and histopathologic characteristics were studied on transverse sections. All preparations were devoid of phosphatidylcholine hydrolysis or oxidation compounds. Solutions without bupivacaine produced transient irritative signs that required sedation in most rabbits. Despite the similar duration of respiratory depression in groups receiving liposomal or plain bupivacaine, liposomes produced significantly prolonged motor blockade (126 vs 70 min). Correction of hypotension after plain bupivacaine required a longer dopamine infusion and larger doses than after liposomal bupivacaine (28 vs 18 min and 74 vs 47 mg). Necrosis was observed in the cervical area of two rabbits (one in the liposomal bupivacaine group and another in the phosphate buffer group). No demyelinated areas were noted in spinal cord examinations. We conclude that liposomal bupivacaine leads to a less severe sympathetic block and to a prolonged motor block, whereas histologic changes are not significantly different among groups. Implications: Multilamellar liposomes containing bupivacaine administered intracisternally to rabbits produce spinal cord histopathologic changes not significantly different from those observed with plain bupivacaine. Sustained release of bupivacaine from liposomes is suggested by the prolonged motor blockade and the reduced severity of arterial hypotension. Use of these liposomes could prolong the local anesthetic effects of bupivacaine.

Colloidal dispersions allow various order-disorder phase transitions to be observed by optical means. These transitions can be understood in terms of free-volume and cohesion-energy considerations provided these concepts are defined not only for the disordered phase, as in the Van der Waals theory, but also for the ordered phase.

Stereotactic radiosurgery treatment principles and irradiation techniques have shown little evolution since its introduction in 1968. Conversely, technology progress linked to computers has produced a major impact on the methods used for treatment planning and dose delivery. In order to fully comprehend modern radiosurgery approaches, one has to acquire good insight of the underlying technology, specifically computer software. In this chapter, we describe the evolution from X-ray films to high-resolution digital imaging, the shift from simple trigonometric calculation to highly complex algorithms and new perspectives in patient follow-up. If these changes open new prospects, they also add complexity, which leads to new pitfalls and limits of the stereotactic radiosurgery method.

Stereotactic radiosurgery treatment principles and irradiation techniques have shown little evolution since its introduction in 1968. Conversely, technology progress linked to computers has produced a major impact on the methods used for treatment planning and dose delivery. In order to fully comprehend modern radiosurgery approaches, one has to acquire good insight of the underlying technology, specifically computer software. In this chapter, we describe the evolution from X-ray films to high-resolution digital imaging, the shift from simple trigonometric calculation to highly complex algorithms and new perspectives in patient follow-up. If these changes open new prospects, they also add complexity, which leads to new pitfalls and limits of the stereotactic radiosurgery method.