2,135 research outputs found
Methodology and analysis methods in clinic of activity
Este artigo trata da metodologia na clínica da atividade. Principia com a definição da noção de atividade, distinguindo-a da atividade realizada e do real da atividade. Estruturado pelos conflitos entre três polos, o próprio sujeito, os outros e seu objeto, esse real da atividade não é passível de ser conhecido ou transformado de modo direto, nem pelo sujeito nem por qualquer outro. Acessar a atividade implica, então, proceder de maneira indireta. O artigo mostra por que e como, para atingir esse fim, se deve “provocar” o desenvolvimento. Essa metodologia usa métodos – autoconfrontação e instruções ao sósia – que permitem a instalação de uma atividade nova, retomando e fazendo reviver os conflitos do real da atividade e as soluções que lhes são dadas. Por fim, um estudo de caso permite ilustrar os efeitos dessa metodologia desenvolvimental em suas duas vertentes: a do aumento do poder de agir e da ampliação do manejo de seu ofício pelos sujeitos em questão e a dos conhecimentos científicos dos processos em jogo
The global water cycle and continental erosion during phanerozoic time (570 my)
Asensitivity study is conducted to determine what effect two mechanisms, namely continental size and latitudinal location might have on the global wtaer cycle. The global water cycle over Phanerozoic time (570 my) is established first by analyzing the distribution of rainfall (P), evaporation (E), and runoff (D), by bands of 10° of latitude, on the Present-day Earth and then applying these values to the ancient Phanerozoic world. In this backward projection, the global cosmic, climatic, and orographic conditions prevailing today, are supposed constant through time, while the only variable parameter controlling the system are the latitudinal positions of the continents and the relative area of continents and oceans.
The calculated Phanerozoic global runoff clearly shows that the humid periods are the Cretaceous (100 my), the Devonian-Silurian (400 my), and the Cambrian (500 my), while the dry periods are close to the Present-day (0 my), and the Permo-Triassic (200 my). The continal global runoff together with the survival rate of the volcanics are used to predict the fluctuations of the isotopic ratio 87Sr/86Sr in marine sediments. Predicted and measured values appear to be in good agreement (except for the Present) which somewhat validate the calculations. The continental runoff is also related to the sedimentation rate and used to estimate the specific erosion rate of the continents through the Phanerozoic. Thus the sedimemtation rate variations are understood as a consequence of the continental runoff fluctuations through time
Situation de la sécurité sanitaire des denrées alimentaires à Madagascar
Résumé— La présente étude sur l’analyse de la situation sanitaire des denrées alimentaires à Madagascar, entre 2016 et la fin du mois de septembre 2020, révèle l’augmentation des cas de TIA, de 398 cas à 908 cas, avec un pic remarquable de 1159 cas en 2019. Cette croissance des cas de TIA dérive de la croissance des TIAC de 1056 cas en 2019, touchant onze régions, après consommation d’aliments à base de sauce mayonnaise et d’autres aliments, contaminés par la salmonella d’une part, et d’autre part, de celle des ICAM de 322 cas en 2020, concernant trois régions, après ingestion de tortues de mer (50,93%), des poissons de mer non définis (38,51%), des requins (8,07%) et des oursins de mer (2,48%), respectivement contaminés par les biotoxines marines provoquant le chélonitoxisme, le ciguatoxisme et le carchatoxisme, et par la palytoxine. La présente étude a également montré que l’insuffisance de la sécurité sanitaire des denrées alimentaires découle des faiblesses et des menaces liées aux facteurs étiologiques, institutionnels, environnementaux, et inhérents aux exploitants alimentaires. Ainsi, des recommandations sont apportées afin de réduire les menaces et faiblesses liées à ces différents facteurs. Par conséquent, elles contribuent fortement à assurer la sécurité alimentaire, améliorer la sécurité nutritionnelle, promouvoir l’agriculture durable, garantir le bien être de tous à tous âges, et atteindre les objectifs de développement durable à l’horizon 2030. Mots-clés—analyses; denrées alimentaires ; gouvernance ; management; sécurité sanitaire. Abstract— This study on the analysis of the food safety situation in Madagascar, between 2016 and the end of September 2020, reveals an increase in foodborne disease cases, from 398 cases to 908 cases, with a remarkable peak of 1159 cases in 2019. This growth in food-borne illnesses cases is derived from the growth in collective food-borne illnesses cases of 1056 cases in 2019, affecting eleven regions, following the consumption of food containing mayonnaise sauce and other food, contaminated with salmonella, on the one hand, and on the other hand, from the growth in intoxications through the consumption of marine animals of 322 cases in 2020, involving three regions, after ingestion of sea turtles (50.93%), undefined sea fish (38.51%), sharks (8.07%) and sea urchins (2.48%), respectively contaminated by marine biotoxins causing chelonitoxism, ciguatoxism and carchatoxism, and by palytoxin. This study also confirmed that the inadequacy of food safety in Madagascar stems from weaknesses and threats related to etiological, institutional, environmental, and farmer-related factors. To this end, recommendations are made, in order to reduce to an acceptable level the threats and weaknesses related to these different factors. As a result, they make an important contribution to ensuring food security, improving nutritional security, promoting sustainable agriculture, ensuring the well-being of all people at all ages, and achieving the Sustainable Development Goals by 2030.
RETRATO DE SEÑORA [Material gráfico]
ADQUIRIDA POR EL COLECCIONISTA EN LA PALMAFOTO SOBRE CARTULINA DE RETRATO DE SEÑORA DE PIE APOYADA EN RESPALDO DE SILLACopia digital. Madrid : Ministerio de Educación, Cultura y Deporte. Subdirección General de Coordinación Bibliotecaria, 201
A cryogenic liquid-mirror telescope on the moon to study the early universe
We have studied the feasibility and scientific potential of zenith observing
liquid mirror telescopes having 20 to 100 m diameters located on the moon. They
would carry out deep infrared surveys to study the distant universe and follow
up discoveries made with the 6 m James Webb Space Telescope (JWST), with more
detailed images and spectroscopic studies. They could detect objects 100 times
fainter than JWST, observing the first, high-red shift stars in the early
universe and their assembly into galaxies. We explored the scientific
opportunities, key technologies and optimum location of such telescopes. We
have demonstrated critical technologies. For example, the primary mirror would
necessitate a high-reflectivity liquid that does not evaporate in the lunar
vacuum and remains liquid at less than 100K: We have made a crucial
demonstration by successfully coating an ionic liquid that has negligible vapor
pressure. We also successfully experimented with a liquid mirror spinning on a
superconducting bearing, as will be needed for the cryogenic, vacuum
environment of the telescope. We have investigated issues related to lunar
locations, concluding that locations within a few km of a pole are ideal for
deep sky cover and long integration times. We have located ridges and crater
rims within 0.5 degrees of the North Pole that are illuminated for at least
some sun angles during lunar winter, providing power and temperature control.
We also have identified potential problems, like lunar dust. Issues raised by
our preliminary study demand additional in-depth analyses. These issues must be
fully examined as part of a scientific debate we hope to start with the present
article.Comment: 35 pages, 11 figures. To appear in Astrophysical Journal June 20 200
Barrett’s Esophagus in Eosinophilic Esophagitis in Swiss Eosinophilic Esophagitis Cohort Study (SEECS)
INTRODUCTION: There is a complex interrelationship between gastroesophageal reflux disease (GERD) and eosinophilic esophagitis (EoE) potentially promoting the occurrence and modulating severity of each other reciprocally. Presence of Barrett’s esophagus (BE) is a defining factor for the diagnosis of GERD. While several studies investigated the potential impact of concomitant GERD on the presentation and course of EoE, little was known with regards to BE in EoE patients. METHODS: We analyzed prospectively collected clinical, endoscopic, and histological data from patients enrolled in the Swiss Eosinophilic Esophagitis Cohort Study (SEECS) regarding differences between EoE patients with (EoE/BE+) versus without BE (EoE/BE−) and determined the prevalence of BE in EoE patients. RESULTS: Among a total of 509 EoE patients included in our analysis, 24 (4.7%) had concomitant BE with a high male preponderance (EoE/BE+ 83.3% vs. EoE/BE− 74.4%). While there were no differences in dysphagia, odynophagia was significantly (12.5 vs. 3.1%, p = 0.047) more common in EoE/BE+ versus EoE/BE−. General well-being at last follow-up was significantly lower in EoE/BE+. Endoscopically, we observed an increased incidence of fixed rings in the proximal esophagus in EoE/BE+ (70.8 vs. 46.3% in EoE/BE−, p = 0.019) and a higher fraction of patients with a severe fibrosis in the proximal histological specimen (8.7 vs. 1.6% in EoE/BE, p = 0.017). CONCLUSION: Our study reveals that BE is twice as frequent in EoE patients compared to general population. Despite many similarities between EoE patients with and without BE, the finding of a more pronounced remodeling in EoE patients with Barrett is noteworthy
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