Plasmon-Driven Acceleration in a Photo-Excited Nanotube

A plasmon-assisted channeling acceleration can be realized with a large channel, possibly at the nanometer scale. Carbon nanotubes (CNTs) are the most typical example of nano-channels that can confine a large number of channeled particles in a photon-plasmon coupling condition. This paper presents a theoretical and numerical study on the concept of high-field charge acceleration driven by photo-excited Luttinger-liquid plasmons (LLP) in a nanotube. An analytic description of the plasmon-assisted laser acceleration is detailed with practical acceleration parameters, in particular with specifications of a typical tabletop femtosecond laser system. The maximally achievable acceleration gradients and energy gains within dephasing lengths and CNT lengths are discussed with respect to laser-incident angles and CNT-filling ratios.Comment: 19 p

Enhancing Information Language Learning with Mobile Technology - Does it Work?

There are many theories that attempt to explain second language acquisition processes and factors determining success or failure. Despite a lack of general agreement between proponents of these theories, research has convincingly shown that the amount of exposure to target language input is one important predictor of ultimate achievement levels. ‘Time on task’ is as important in language learning as it is in many other domains (cf. Reber, 1993) and it is therefore important to identify ways in which this can be increased. An obvious possibility is to encourage learners to engage with (and in) the language outside the classroom. Informal learning, in the sense of learning outside of formal education, has been shown to be a major aspect of adult learning (Cross, 2007) and, given appropriate preparation and support, learners can greatly increase opportunities for learning if they can do so independently. Mobile technologies have obvious potential in this regard. However, is it possible to improve language skills in this way? In this article we report on an exploratory study into the use of cellphones for extensive listening practice. We used input enhancement to draw learners’ attention to not only the meaning of the materials but also the formal (grammatical) aspects of the input. We found that the use of mobile technology presented a number of challenges and in this study did not result in learners acquiring the target structures. We conclude with a number of recommendations for the use and future study of mobile technologies for (language) learning

Institutional Change, Obsolescing Legitimacy, and Multinational Corporations: The Case of the Central American Banana Industry

This paper studies the practice of integration of influential host country actors to a multinational corporation as a strategy to decrease problems of legitimacy to the foreign firm before the host country's society. By developing the concept of obsolescing legitimacy, we argue that this strategy provides legitimacy to the foreign firm only in the absence of institutional changes in the host country. Once these changes take place, an alliance by the multinational to an elite or a political system no longer ruling the host country will become a liability and will generate problems of legitimacy for the multinational. We illustrate our argument with the case of the US multinational United Fruit Company in Central America.