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La philosophie et le climat

International audienceC'est au cours du colloque ''Atmosphère et climat" qui s'est déroulé à Paris le 4 mars 1989, sous l'égide du Président de l'Assemblée Nationale, Laurent FABIUS, et devant un auditoire de scientifiques et d'administrateurs. que Michel Serres a prononcé cette exemplaire leçon de philosophie naturelle et politique, dont nous publions le texte in extenso. Michel Serres a eu la gentillesse de nous autoriser à reproduire ses propos, qu'il en soit remercié ici

Pulgarcita y Pulgarcito en el siglo XXI

This new scholar, this young student, has never seen a calf, a cow, a pig much less a nest. In 1900, the majority of humans on the planet, were engaged in agriculture and livestock; in 2010 France, like other countries similar to ours, only has 1% of farmers. Undoubtedly one must see one of the most immense ruptures in history since the Neolithic. In another moment, referred to the geological practices, the culture changes.The one or the one that I present to you no longer lives in the company of the living, no longer lives in the same land, does not have the same relationship with the world. He or she only sees the Arcadian nature of holidays, leisure time or tourism. He inhabits the city. His immediate predecessors, much more than half, worked the field. Nevertheless, he has become sensitive to environmental issues. Prudent, he will contaminate less than the others, adults, unconscious and narcissuses.Este nuevo escolar, esta joven estudiante, nunca han visto un becerro, una vaca, un cerdo mucho menos un nido. En 1900, la mayoría de los humanos sobre el planeta, se ocupaban de la agricultura y la ganadería; en el 2010 Francia, como otros países semejantes al nuestro, sólo cuenta con un 1% de campesinos. Sin duda hay que ver allí una de las más inmensas rupturas de la historia desde el neolítico. En otro momento, referida a las prácticas geórgicas, la cultura cambia.Aquel o aquella que les presento ya no vive en compañía de los vivos, ya no vive en la misma tierra, no tiene pues la misma relación con el mundo. Él o ella solo ven la naturaleza arcadiana de las vacaciones, del tiempo libre o del turismo. Él habita la ciudad. Sus predecesores inmediatos, mucho más de la mitad, trabajaban el campo. No obstante, él se ha vuelto sensible a las cuestiones del medio. Prudente, él contaminará menos que los demás, adultos, inconscientes y narcisos

Expression, localization and functions in acrosome reaction and sperm motility of Ca(V)3.1 and Ca(V)3.2 channels in sperm cells: an evaluation from Ca(V)3.1 and Ca(V)3.2 deficient mice.: Cav3.1/3.2 channel functions in sperm physiology

International audienceIn spermatozoa, voltage-dependent calcium channels (VDCC) have been involved in different cellular functions like acrosome reaction (AR) and sperm motility. Multiple types of VDCC are present and their relative contribution is still a matter of debate. Based mostly on pharmacological studies, low-voltage-activated calcium channels (LVA-CC), responsible of the inward current in spermatocytes, were described as essential for AR in sperm. The development of Ca(V)3.1 or Ca(V)3.2 null mice provided the opportunity to evaluate the involvement of such LVA-CC in AR and sperm motility, independently of pharmacological tools. The inward current was fully abolished in spermatogenic cells from Ca(V)3.2 deficient mice. This current is thus only due to Ca(V)3.2 channels. We showed that Ca(V)3.2 channels were maintained in sperm by Western-blot and immunohistochemistry experiments. Calcium imaging experiments revealed that calcium influx in response to KCl was reduced in Ca(V)3.2 null sperm in comparison to control cells, demonstrating that Ca(V)3.2 channels were functional. On the other hand, no difference was noticed in calcium signaling induced by zona pellucida. Moreover, neither biochemical nor functional experiments, suggested the presence of Ca(V)3.1 channels in sperm. Despite the Ca(V)3.2 channels contribution in KCl-induced calcium influx, the reproduction parameters remained intact in Ca(V)3.2 deficient mice. These data demonstrate that in sperm, besides Ca(V)3.2 channels, other types of VDCC are activated during the voltage-dependent calcium influx of AR, these channels likely belonging to high-voltage activated Ca(2+) channels family. The conclusion is that voltage-dependent calcium influx during AR is due to the opening of redundant families of calcium channels

Nonhumans in participatory design

© 2018, © 2018 Informa UK Limited, trading as Taylor & Francis Group. This article examines the role that nonhumans play in participatory design. Research and practice concerned with participatory design mostly focuses on human participants, however nonhumans also participate in the design process and can play a significant role in shaping the process. This article focuses on how nonhumans participate in the design process. An empirical case study is used to illustrate how humans and nonhumans assemble to form networks in order to effect a design. Nonhumans increase the level of participation in a design process. The case study reveals how nonhumans help to maintain, destroy or strengthen networks by substituting, mediating and communicating with humans and often, in doing so, making human actors more or less visible in the process. Nonhumans play a part in configuring the social. Revealing the presence and roles of nonhumans is an important means through which to increase the democracy within the design process