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“This is something that, every time I think about it, I imagine how could human kind become dependent on something that is going to finish some day? This is stupidity. I can’t understand why. How could, in less than 50 years, because it was in the first half of the 20th century, the whole human kind became dependent on something that is going to be(More)
Recent improvements of Bureau National de Me/spl acute/trologie Syste/spl grave/mes de Re/spl acute/fe/spl acute/rence Temps Espace (BNM-SYRTE) fountains FO1 and FO2 are described. Fractional frequency instabilities of 2.9/spl times/10/sup -14//spl tau//sup -1/2/ for FO1 and 1.6/spl times/10/sup -14//spl tau//sup -1/2/ for FO2 have been demonstrated. A(More)
We present a comparison between SYRTE's Cs fountain FO1 and Cs-Rb fountain FO2 using a cryogenic sapphire oscillator (CSO) to generate an ultra-stable interrogation signal. A description of the experimental setup is given and the clock accuracies are discussed. For the first time, a frequency resolution in the low 10/sup -16/ is achieved in the comparison(More)
The change in the economic policies that began with the military coup and the economic policies pursued in the wake of the economic crisis of the sixties turned Brazil from a coffee exporter to one of the most important agricultural and food exporters in the world. Starting in the seventies, Brazil rapidly assumed a prominent role in important external(More)
In the context of reorganization of production in the sugar and alcohol industry, mechanization of sugar cane harvesting has been justified as a protective measure for the environment and workers. This article focuses on the consequences of organization of work in mechanization of sugar cane harvesting with regard to the harvester operators' health. Based(More)
In this work, an investigation and analysis are carried out in order to observe the relationship between ethanol spot and futures prices in Brazil. We adopted the Engle and Granger co-integration approach. Also, we consider the information share method proposed by Hasbrouck in order to examine the market efficiency in price discovery and information(More)
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