429 research outputs found
Intrusion and extrusion of water in hydrophobic mesopores
We present experimental and theoretical results on intrusion-extrusion cycles
of water in hydrophobic mesoporous materials, characterized by independent
cylindrical pores. The intrusion, which takes place above the bulk saturation
pressure, can be well described using a macroscopic capillary model. Once the
material is saturated with water, extrusion takes place upon reduction of the
externally applied pressure; Our results for the extrusion pressure can only be
understood by assuming that the limiting extrusion mechanism is the nucleation
of a vapour bubble inside the pores. A comparison of calculated and
experimental nucleation pressures shows that a proper inclusion of line tension
effects is necessary to account for the observed values of nucleation barriers.
Negative line tensions of order are found for our
system, in reasonable agreement with other experimental estimates of this
quantity
Crowdsourcing for agricultural applications: A review of uses and opportunities for a farmsourcing approach
peer reviewedAbstract Crowdsourcing, understood as outsourcing tasks or data collection by a large group of non-professionals, is increasingly used in scientific research and operational applications. In this paper, we reviewed crowdsourcing initiatives in agricultural science and farming activities and further discussed the particular characteristics of this approach in the field of agriculture. On-going crowdsourcing initiatives in agriculture were analysed and categorised according to their crowdsourcing component. We identified eight types of agricultural data and information that can be generated from crowdsourcing initiatives. Subsequently we described existing methods of quality control of the crowdsourced data. We analysed the profiles of potential contributors in crowdsourcing initiatives in agriculture, suggested ways for increasing farmers’ participation, and discussed the on-going initiatives in the light of their target beneficiaries. While crowdsourcing is reported to be an efficient way of collecting observations relevant to environmental monitoring and contributing to science in general, we pointed out that crowdsourcing applications in agriculture may be hampered by privacy issues and other barriers to participation. Close connections with the farming sector, including extension services and farm advisory companies, could leverage the potential of crowdsourcing for both agricultural research and farming applications. This paper coins the term of farmsourcing as a professional crowdsourcing strategy in farming activities and provides a source of recommendations and inspirations for future collaborative actions in agricultural crowdsourcing
Autre cause de mort subite du nourrisson: à propos d’un cas clinique de syndrome du QT long congenital
Le syndrome du QT long congénital est une maladie rythmique liée à une mutation génétique et caractérisée par un espace QT allongé sur l'électrocardiogramme, des arythmies malignes type torsade de pointe et fibrillation ventriculaire entraînant une mort subite. Les gènes impliqués dans ces mutations codent pour des sous unités des canaux ioniques responsables de l'activité électrique cardiaque. Le diagnostic est basé sur l'électrocardiogramme, une enquête familiale et l'étude génétique. Le traitement repose sur les bêtabloquants, la sympathectomie et le stimulateur cardiaque. Nous rapportons le cas d'un nourrisson de 2 ans retrouvé en état de mort apparente. Nous discutons de sa prise en charge initiale, de l'enquête familiale et de son suivi ultérieur.Key words: Syndrome du QT long, canalopathie rythmique, mort subit
Montréal et Vancouver, métro-pôles d'un univers : L'hiver de Mira Christophe de Pierre Nepveu
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