The effect of plasma density on toroidal rotation was examined in density ramp-up experiments at a plasma current of 1 MA and a toroidal magnetic field of 3.6 T in Tore Supra ohmic discharges. Experimental measurements have shown that the toroidal rotation amplitude is reduced at all radii when increasing the plasma density, although it remains in the countercurrent direction. Neoclassical predictions including ripple-induced toroidal friction are in qualitative agreement with such observations. However, in the core (r/a < 0.5) the plasma accelerates at n l ∼ 3 × 10 19 m −2 and breaks again above n l ∼ 3.5 × 10 19 m −2 . This rotation bifurcation did not appear to be correlated to a possible influence of the sawtooth activity. Nonetheless, quasi-linear gyrokinetic simulations have shown that the transition of the nature of linear microinstabilities from ITG-TEM to pure ITG occurs at n l ∼ 3 × 10 19 m −2 , which could indicate a change on the turbulence driven contributions and explain the deviation from neoclassical predictions in the plasma core.
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In Brazilian Portuguese, words with antepenultimate syllable stress are regarded as exceptions to lexical stress rules. Evidence for their exceptionality has been given in the literature: the late introduction of these words in the language, the predominant occurrence of the antepenultimate syllable stress in low frequency words, and the tendency of the language to shift stress to the penultimate syllable. Using a corpus of 18,413 words with antepenultimate stress and their respective phonological transcription from the Houaiss dictionary (HOUAISS VILLAR 2001), we argue that these claims are not always accurate and that words with antepenultimate stress are a long established and consistent pattern in the language. Furthermore, we show that stress shift to the penultimate syllable is not the rule, but it is only one possibility, restricted by the phonotactics of the language, and that preservation of antepenultimate stress is far more frequent. The data and analyses presented in this paper argue that prediction of lexical stress in Brazilian Portuguese must include words with the antepenultimate pattern, as there is no evidence that they are either disappearing in the language or being avoided by speakers.
This paper summarizes experimental results from recent studies on intrinsic rotation at the plasma edge of the TCABR tokamak. These results were obtained after upgrading the number of channels of the rotation diagnostic to three. The measurements were carried out in the collisional (Pfirsch-Schluter) regime and the rotation profiles of the ions were obtained from the Doppler shifts of the impurity carbon lines, CIII (464.74 nm), and CVI (529.06 nm). Results on the correlation between toroidal rotation at the plasma edge and direction of gas injection are also presented. They indicate that the direction of gas injection has a small effect on rotation; the velocity of the background neutral hydrogen is affected by direct momentum transfer from the injected gas (also hydrogen), while the carbon ions' velocity is affected by inward radial friction force between the injected gas atoms and ions, increasing their velocity in the opposite sense of the plasma current.
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