Twitch potentia induced by two different modalities of neuromuscular electrical stimulation: implications for motor unit recruitment.

INTRODUCTION: We tested the hypothesis that twitch potentiation would be greater following conventional (CONV) neuromuscular electrical stimulation (50-µs pulse width and 25-Hz frequency) compared with wide-pulse high-frequency (WPHF) neuromuscular electrical stimulation (1-ms, 100-Hz) and voluntary (VOL) contractions, because of specificities in motor unit recruitment (random in CONV vs. random and orderly in WPHF vs. orderly in VOL). METHODS: A single twitch was evoked by means of tibial nerve stimulation before and 2 s after CONV, WPHF, and VOL conditioning contractions of the plantar flexors (intensity: 10% maximal voluntary contraction; duration: 10 s) in 13 young healthy subjects. RESULTS: Peak twitch increased (P<0.05) after CONV (+4.5±4.0%) and WPHF (+3.3±5.9%), with no difference between the 2 modalities, whereas no changes were observed after VOL (+0.8±2.6%). CONCLUSIONS: Our results demonstrate that presumed differences in motor unit recruitment between WPHF and CONV do not seem to influence twitch potentiation results.

La force motrice hydraulique au service du développement économique helvétique : L'exemple du réseau d'eau sous pression à Lausanne 1868-1914

The success story of hydroelectricity long influenced and dominated Swiss scholarly literature devoted to the history of technology. This means of conducting power, which emerged at the end of the 19th century and is still dominating today, has attracted much more attention than technologies that have been shadowed by its success. In spite of their important contribution to Swiss economic development, the distribution networks of pressurized water have been neglected by scholars. This article contributes to close this historiographic gap by analyzing the introduction of pressurized water distribution in 1876 in Lausanne, in the context of the building of the first Swiss cable funicular between Lausanne and Ouchy. This article shows how pressurized water distribution transformed socio-economic practices in the urban areas in which it was adopted. Indeed, this innovation, which allowed the use of distant hydraulic resources, enabled the rationalization of industrial and artisanal production as well as improved the density of the urban industrial base. By facilitating the introduction of electric lighting, pressurized water networks played a key role in the early development, and further successes, of the Swiss hydroelectric industry.

[Palette des couleurs]. VIIII : [version "terre rouge"] : [estampe] / [gravé sous la direction de Jacob Christoph Le Blon]

Référence bibliographique : Singer, 46

[Tête de jeune fille]. II : [estampe] ([2eme état en deux plaques, imprimé en jaune et bleu]) / [gravé sous la direction de Jacob Christoph Le Blon] ; [d'après Carlo Maratti ?]

Référence bibliographique : Singer, 45

Les douanières allemandes publiées sous le patronage de la chambre de commerce de Nancy ; délibération du 22 janvier 1875

[Loi. (Recueil)]

[Tête de jeune fille]. III : [estampe] ([3eme état en plusieurs plaques, imprimé en jaune, bleu et rouge]) / [gravé sous la direction de Jacob Christoph Le Blon] ; [d'après Carlo Maratti ?]

Référence bibliographique : Singer, 45

[Tête de jeune fille]. I : [estampe] ([1er état en une plaque, imprimé en noir]) / [gravé sous la direction de Jacob Christoph Le Blon] ; [d'après Carlo Maratti ?]

Référence bibliographique : Singer, 45

[Palette des couleurs]. VII : [version "vermillion"] : [estampe] / [gravé sous la direction de Jacob Christoph Le Blon]

Référence bibliographique : Singer, 46

[Tête de jeune fille]. VIII : [estampe] ([6eme état en plusieurs plaques, imprimé en jaune, bleu et rouge]) / [gravé sous la direction de Jacob Christoph Le Blon] ; [d'après Carlo Maratti ?]

Référence bibliographique : Singer, 45

[Tête de jeune fille]. VI : [estampe] ([5eme état en plusieurs plaques, imprimé en jaune, bleu et rouge]) / [gravé sous la direction de Jacob Christoph Le Blon] ; [d'après Carlo Maratti ?]

Référence bibliographique : Singer, 45