453 research outputs found

    Conserves alimentaires

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    A la coberta: "Petite encyclopedie pratique de chimie industrielle. Publiée sous la direction de F. Billon, ingéniéur-chimiste"Amb publicita

    The Future of Environmental Peace and Conflict Research

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    Interest in the intersections of environmental issues, peace and conflict has surged in recent years. Research on the topic has developed along separate research streams, which broadened the knowledge base considerably, but hardly interact across disciplinary, methodological, epistemological and ontological silos. Our forum addresses this gap by bringing into conversation six research streams on the environment, peace and conflict: environmental change and human security, climate change and armed conflict, environmental peacebuilding, political ecology, securitisation of the environment, and decolonizing environmental security. For each research stream, we outline core findings, potentials for mutual enrichment with other streams, and prospects for future research

    Eureka and beyond: mining's impact on African urbanisation

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    This collection brings separate literatures on mining and urbanisation together at a time when both artisanal and large-scale mining are expanding in many African economies. While much has been written about contestation over land and mineral rights, the impact of mining on settlement, notably its catalytic and fluctuating effects on migration and urban growth, has been largely ignored. African nation-states’ urbanisation trends have shown considerable variation over the past half century. The current surge in ‘new’ mining countries and the slow-down in ‘old’ mining countries are generating some remarkable settlement patterns and welfare outcomes. Presently, the African continent is a laboratory of national mining experiences. This special issue on African mining and urbanisation encompasses a wide cross-section of country case studies: beginning with the historical experiences of mining in Southern Africa (South Africa, Zambia, Zimbabwe), followed by more recent mineralizing trends in comparatively new mineral-producing countries (Tanzania) and an established West African gold producer (Ghana), before turning to the influence of conflict minerals (Angola, the Democratic Republic of Congo and Sierra Leone)

    Environmental Asbestotic Pleural Plaques in Northeast Corsica: Correlations with Airborne and Pleural Mineralogic Analysis

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    We report a prevalence study of environmental pleural plaques in subjects over 50 years old from the northeastern Corsican village of Murato, built on asbestos surface deposits. The percentage of plaques was 41%, versus 7.5% in the control village of Vezzani. Although surface deposits contain both chrysotile and tremolite, airborne pollution and asbestos lung burden of exposed inhabitants consist essentially of tremolite as assessed by transmission electron microscopy (TEM). However, TEM analysis of the parietal pleura of three animals bred in exposed areas showed a predominance of short fibers of chrysotile. The respective roles of tremolite and chrysotile in inducing pleural plaques in Corsica should thus be considered.—Environ Health Perspect 102(Suppl 5):251–252 (1994

    Factors affecting metal mobilisation during oxidation of sulphidic, sandy wetland substrates

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    Most metals accumulate as sulphides under anoxic conditions in wetland substrates, reducing their bioavailability due to the solubility of metal sulphides. However, upon oxidation of these sulphides when the substrate is occasionally oxidised, metals can be released from the solid phase to the pore water or overlaying surface water. This release can be affected by the presence of carbonates, organic matter and clay. We compared changes of Cd, Cu and Zn mobility (CaCl2 extraction) during oxidation of a carbonate-rich and a carbonate-poor sulphidic, sandy wetland substrate. In addition, we studied how clay with low and high cation sorption capacity (bentonite and kaolinite, respectively) and organic matter (peat) can counteract Cd, Cu and Zn release during oxidation of both carbonate-rich and carbonate-poor sulphidic sediments. CaCl2-extractability of Cu, a measure for its availability, is low in both carbonate-poor and carbonate-rich substrates, whereas its variability is high. The availability of Cd and Zn is much higher and increases when peat is supplied to carbonate-poor substrates. A strong reduction of Cd and Zn extractability is observed when clay is added to carbonate-poor substrates. This reduction depends on the clay type. Most observations could be explained taking into account pH differences between treatments, with kaolinite resulting in a lower pH in comparison to bentonite. These pH differences affect the presence and characteristics of dissolved organic carbon and the metal speciation, which in turns affects the interaction of metals with the solid soil phase. In carbonate-rich substrates, Cd and Zn availability is lower and the effects of peat and clay amendment are less clear. The latter can also be attributed to the high pH and lack of pH differences between treatments

    Assessment of Patient Satisfaction Using a New Augmented Reality Simulation Software for Breast Augmentation: A Prospective Study

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    Background: Breast augmentation is one of the most frequently performed plastic surgery procedures. Providing patients with realistic 3D simulations of breast augmentation outcomes is becoming increasingly common. Until recently, such programs were expensive and required significant equipment, training, and office space. New simple user-friendly programs have been developed, but to date there remains a paucity of objective evidence comparing these 3D simulations with post-operative outcomes. The aim of this study is to assess the aesthetic similarity between a preoperative 3D simulation generated using Arbrea breast simulation software and real post-operative outcomes, with a focus on patient satisfaction. Methods: The authors conducted a prospective study of patients requiring breast augmentation. Patients were asked to assess how realistic the simulation was compared to the one-year post-operative result using the authors’ grading scale for breast augmentation simulation assessment. Patient satisfaction with the simulations was assessed using a satisfaction visual analogue scale (VAS) ranging from 0 (not at all satisfied) to 10 (very satisfied). Patient satisfaction with the surgical outcome was assessed using the BREAST-Q Augmentation Module. Results: All patients were satisfied with the simulations and with the attained breast volume, with a mean VAS score of 8.2   1.2. The mean simulation time took 90 s on average. The differences between the pre-operative and one-year post-operative values of the three BREAST-Q assessments were found to be statistically significant (p < 0.001). Conclusions: Three-dimensional simulation is becoming increasingly common in pre-operative planning for breast augmentation. The present study aimed to assess the degree of similarity of three-dimensional simulations generated using Arbrea Breast Software and found that the use of the software provided a very satisfying representation for patients undergoing breast augmentation. However, we recommend informing patients that only the volume simulation is extremely accurate. On the other hand, it is necessary to not guarantee an absolute correspondence regarding the breast shape between the simulation and the post-operative result

    Field Induced Reduction of the Low Temperature Superfluid Density in YBa2Cu3O6.95

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    A novel high magnetic field (8 T) spectrometer for muon spin rotation has been used to measure the temperature dependence of the in-plane magnetic penetration depth in YBa2Cu3O6.95. At low H and low T, the penetration depth exhibits the characteristic linear T dependence associated with the energy gap of a d_x^2-y^2-wave superconductor. However, at higher fields the penetration depth is essentially temperature independent at low T. We discuss possible interpretations of this surprising new feature in the low-energy excitation spectrum.Comment: 8 pages, 4 figures, 1 RevTex file and 4 postscript figure

    Frustrated kinetic energy, the optical sum rule, and the mechanism of superconductivity

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    The theory that the change of the electronic kinetic energy in a direction perpendicular to the CuO-planes in high-temperature superconductors is a substantial fraction of the condensation energy is examined. It is argued that the consequences of this theory based on a rigorous cc-axis conductivity sum rule are consistent with recent optical and penetration depth measurements.Comment: 4 pages (RevTeX) and 2 eps figure

    New 3-Dimensional Volumetric Ultrasound Method for Accurate Quantification of Atherosclerotic Plaque Volume.

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    Carotid and femoral plaque burden is a recognized biomarker of cardiovascular disease risk. A new electronic-sweep 3-dimensional (3D)-matrix transducer method can improve the functionality and image quality of vascular ultrasound atherosclerosis imaging. This study aimed to validate this method for plaque volume measurement in early and intermediate-advanced plaques in the carotid and femoral territories. Plaque volumes were measured ex vivo in pig carotid and femoral artery specimens by 3-dimensional vascular ultrasound (3DVUS) using a 3D-matrix (electronic-sweep) transducer and its associated 3D plaque quantification software, and were compared with gold-standard histology. To test the clinical feasibility and accuracy of the 3D-matrix transducer, an experiment was conducted in intermediate-high risk individuals with carotid and femoral atherosclerosis. The results were compared with those obtained using the previously validated mechanical-sweep 3D transducer and established 2-dimensional (2D)-based plaque quantification software. In the ex vivo study, the authors assessed 19 atherosclerotic plaques (plaque volume, 0.76 µL-56.30 μL), finding strong agreement between measurements with the 3D-matrix transducer and the histological gold-standard (intraclass correlation coefficient [ICC]: 0.992; [95% CI: 0.978-0.997]). In the clinical analysis of 20 patients (mean age 74.6 ± 4.45 years; 40% men), the authors found 64 (36 carotid and 28 femoral) of 80 scanned territories with atherosclerosis (measured atherosclerotic volume, 10 μL-859 μL). There was strong agreement between measurements made from electronic-sweep and mechanical-sweep 3DVUS transducers (ICC: 0.997 [95% CI: 0.995-0.998]). Agreement was also high between plaque volumes estimated by the 2D and 3D plaque quantification software applications (ICC: 0.999 [95% CI: 0.998-0.999]). Analysis time was significantly shorter with the 3D plaque quantification software than with the 2D multislice approach with a mean time reduction of 46%. 3DVUS using new matrix transducer technology, together with improved 3D plaque quantification software, simplifies the accurate volume measurement of early (small) and intermediate-advanced plaques located in carotid and femoral arteries.This study was partially funded by grants from the Ministerio de Economia, Industria y Competividad (MEIC) with cofunding from the European Regional Development Fund (ERDF) (SAF2016-75580-R to Dr Bentzon) and (BES-2016-076633 to Dr Nogales). Research funding was also received from the Instituto de Salud Carlos III Spain (PIE16/ 00021 to Drs Bueno and Fuster). The CNIC is supported by the Min- isterio de Ciencia, Innovacion y Universidades (MICINN) and the Pro CNIC Foundation and is a Severo Ochoa Center of Excellence (CEX2020-001041-S). This study forms part of a Master Research Agreement between the CNIC and Philips Healthcare. Drs Sánchez- González, Entrekin, and Collet-Billon are employees of Philips Healthcare. All other authors have reported that they have no re- lationships to disclose related to the contents of this paper.S

    Melting and Dimensionality of the Vortex Lattice in Underdoped YBa2Cu3O6.60

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    Muon spin rotation measurements of the magnetic field distribution in the vortex state of the oxygen deficient high-Tc superconductor YBa{2}Cu{3}O{6.60} reveal a vortex-lattice melting transition at much lower temperature than that in the fully oxygenated material. The transition is best described by a model in which adjacent layers of ``pancake'' vortices decouple in the liquid phase. Evidence is also found for a pinning-induced crossover from a solid 3D to quasi-2D vortex lattice, similar to that observed in the highly anisotropic superconductor Bi{2+x}Sr{2-x}CaCu{2}O{8+y}.Comment: 8 pages, 4 figures, 5 postscript file
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