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Climate proxy data are required for improved understanding of climate variability and change in the pre-instrumental period. We present the first international initiative to compile and share information on pro pluvia rogation ceremonies, which is a well-studied proxy of agricultural drought. Currently, the database has more than 3500 dates of celebration of rogation ceremonies, providing information for 153 locations across 11 countries spanning the period from 1333 to 1949. This product provides data for better understanding of the pre-instrumental drought variability, validating natural proxies and model simulations, and multi-proxy rainfall reconstructions, amongst other climatic exercises. The database is freely available and can be easily accessed and visualized via http://inpro.unizar.es/ .
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We hypothesized that Cholera (Vibrio cholerae) that appeared along Lake Kivu in the African Rift in the seventies, might be controlled by volcano-tectonic activity, which, by increasing surface water and groundwater salinity and temperature, may partly rule the water characteristics of Lake Kivu and promote V. cholerae proliferation. Volcanic activity (assessed weekly by the SO2 flux of Nyiragongo volcano plume over the 2007-2012 period) is highly positively correlated with the water conductivity, salinity and temperature of the Kivu lake. Over the 2007-2012 period, these three parameters were highly positively correlated with the temporal dynamics of cholera cases in the Katana health zone that border the lake. Meteorological variables (air temperature and rainfall), and the other water characteristics (namely pH and dissolved oxygen concentration in lake water) were unrelated to cholera dynamics over the same period. Over the 2016-2018 period, we sampled weekly lake water salinity and conductivity, and twice a month vibrio occurrence in lake water and fish. The abundance of V. cholerae in the lake was positively correlated with lake salinity, temperature, and the number of cholera cases in the population of the Katana health zone. V. cholerae abundance in fishes was positively correlated with V. cholerae abundance in lake water, suggesting that their consumption directly contaminate humans. The activity of the volcano, by controlling the physico-chemical characteristics of Lake Kivu, is therefore a major determinant of the presence of the bacillus in the lake. SO2 fluxes in the volcano plume can be used as a tool to predict epidemic risks.
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Cólera/epidemiología , Lagos/química , Lagos/microbiología , Erupciones Volcánicas/efectos adversos , Animales , República Democrática del Congo/epidemiología , Conductividad Eléctrica , Peces/microbiología , Humanos , Concentración de Iones de Hidrógeno , Oxígeno/análisis , Rwanda , Salinidad , Dióxido de Azufre/análisis , Temperatura , Vibrio , Microbiología del AguaRESUMEN
The search for new surface sensitive probes that characterize the surface structure of shape and size-controlled nanoparticles is an interesting topic to properly understand the correlations between electrocatalytic properties and surface structure at the nanoscale. Herein, we report the use of Cu UPD to characterize, not only qualitatively but also quantitatively, the surface structure of different Pd nanoparticles with controlled particle shape and size. Thus, Pd nanoparticles with cubic, octahedral and rhombic dodecahedral shapes, that is, with preferential {100}, {111}, and {110} surface structures, respectively, were prepared. In addition, cubic Pd nanoparticles with different particles sizes and spherical (2-3 nm) Pd nanoparticles were also synthesized. Based on the Cu UPD results on Pd single crystals, a new approach is proposed to qualitatively and quantitatively determine the percentages of {100}, {111}, and {110} surface domains present at the surface of the different shape and size controlled Pd nanoparticles. The results reported clearly show the benefits of this Cu UPD to get detailed information of the surface structure of the nanoparticles according to their particle shape and size.
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The electrocatalytic properties of palladium nanocubes towards the electrochemical oxidation of formic acid were studied in H(2)SO(4) and HClO(4) solutions and compared with those of spherical Pd nanoparticles. The spherical and cubic Pd nanoparticles were characterized by transmission electron microscopy (TEM) and X-ray diffraction (XRD). The intrinsic electrocatalytic properties of both nanoparticles were shown to be strongly dependent on the amount of metal deposited on the gold substrate. Thus, to properly compare the activity of both systems (spheres and nanocubes), the amount of sample has to be optimized to avoid problems due to a lower diffusion flux of reactants in the internal parts of the catalyst layer resulting in a lower apparent activity. Under the optimized conditions, the activity of the spheres and nanocubes was very similar between 0.1 and 0.35 V. From this potential value, the activity of the Pd nanocubes was remarkably higher. This enhanced electrocatalytic activity was attributed to the prevalence of Pd(100) facets in agreement with previous studies with Pd single crystal electrodes. The effect of HSO(4)(-)/SO(4)(2-) desorption-adsorption was also evaluated. The activity found in HClO(4) was significantly higher than that obtained in H(2)SO(4) in the whole potential range.
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Abruptly, in April 2010, airline companies, insurers and politicians discovered that volcanic ash from Iceland could disrupt air traffic throughout western Europe. Like the Xynthia storm that had hit the west coast of France a few years previously, this was a totally "new" and completely unexpected scenario. However, archives of the French Royal Society of Medicine preserved in the library of the National Academy of Medicine, together with European parochial registers, showed that this event was perfectly predictable. Indeed, on 8 June 1783, the Icelandic volcano Laki entered an eruptive phase lasting nearly a year, spewing massive amounts of smoke which, within hours, was observed in France by correspondents of Vicq d'Azyr and by Father Cotte. These "sulfurous fogs", in addition to terrorizing the population, were quickly suspected of being harmful to health. This fear was amply confirmed by the mortality peak recorded by priests of France and Navarre
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Erupciones Volcánicas/historia , Contaminación del Aire/efectos adversos , Europa (Continente) , Historia del Siglo XVIII , Humanos , Mortalidad/historia , Salud Pública , Erupciones Volcánicas/efectos adversosRESUMEN
Complex dysmorphies, asymmetries can affect the various elements of the stomatognathic system: cranial base, maxilla, mandible, musculature and dental arches, in the three dimensions of space. Their etiopathogenesis, as well as their clinical forms, vary considerably. Dysembryopathies, growth disorders, TMJ damages, postural or functional disorders and dental anomalies can create, according to their severity and their moment of appearance, severe or minor facial asymmetries, or asymmetries of the arches. An exo- and endobuccal clinical examination endeavors to specify the localization and the severity of the damage, and to evaluate the importance of the possible alveolar compensations. Consolidated by additional examinations, it enables the clinician to differentiate the various forms of asymmetries.
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Asimetría Facial/etiología , Asimetría Facial/patología , Anomalías Craneofaciales/complicaciones , Asimetría Facial/clasificación , Asimetría Facial/epidemiología , Humanos , Traumatismos Maxilofaciales/complicaciones , Prevalencia , Cráneo/embriología , Anomalías Dentarias/complicacionesRESUMEN
From an orthodontic point of view, asymmetries can be gathered in three great clinical entities: mandibular lateral deviations, dental asymmetries without skeletal involvement, skeletal asymmetries. Once the therapeutic aims and the principles of the orthodontic approach of these dysmorphoses have been recalled, the authors present the various orthodontic means implemented in this type of treatment. Four cases treated illustrate those types of treatment. Vertical non-surgical asymmetry may have an obvious local origin, for instance, a unilateral damage to a nerve. but usually, there is no evident origin. Frequently the occlusal slippage of a severe sagittal or a vertical malformation, which may evolve as a borderline surgery case, is suspected to be the real cause. In these cases, the diagnosis is always late, with the ending growth. The treatment needs peculiar strong asymmetric mechanics and, sometimes, unilateral mixed extractions. The post-treatment occlusion can be unstable; for this reason, the finishing steps must be carefully conducted. Four clinical case reports develop these points ov view. Multidisciplinary treatments prove very useful to solve three types of clinical situations. In the adult patient, facial esthetics are indicated in severe dentofacial asymmetries. Esthetic improvements of dental nature are still required in deviated smiles, or frontal tippings of the occlusal plane. In addition, asymmetrical intermaxillary relationships will lead to functional anomalies: TMJ disorders, dental wear or lingual dysfunctions. Finally, multidisciplinary treatments in the adult concern the occlusal transverse anomalies, the lateral crossbites, the Class II subdivisions, the deviations of the inter-incisor midlines or unilateral edentulousness. The various plans of treatment, as well as the orthodontic mechanics used, are illustrated in the following development by clinical cases.