The effect of smoking nicotine tobacco versus smoking deprivation on motion sickness

BACKGROUND: The experienced smoker maintains adequate nicotine levels by 'puff-by-puff self-control' which also avoids symptomatic nauseating effects of nicotine overdose. It is postulated that there is a varying 'dynamic threshold for nausea' into which motion sickness susceptibility provides an objective toxin-free probe. Hypotheses were that: (i) nicotine promotes motion sickness whereas deprivation protects; and (ii) pleasurable effects of nicotine protect against motion sickness whereas adverse effects of withdrawal have the opposite effect. METHODS: Twenty-six healthy habitual cigarette smokers (mean±SD) 15.3±7.6cigs/day, were exposed to a provocative cross-coupled (coriolis) motion on a turntable, with sequences of 8 head movements every 30s. This continued to the point of moderate nausea. Subjects were tested after either ad-lib normal smoking (SMOKE) or after overnight deprivation (DEPRIV), according to a repeated measures design counter-balanced for order with 1-week interval between tests. RESULTS: Deprivation from recent smoking was confirmed by objective measures: exhaled carbon monoxide CO was lower (P<0.001) for DEPRIV (8.5±5.6ppm) versus SMOKE (16.0±6.3ppm); resting heart rate was lower (P<0.001) for DEPRIV (67.9±8.4bpm) versus SMOKE (74.3±9.5bpm). Mean±SD sequences of head movements tolerated to achieve moderate nausea were more (P=0.014) for DEPRIV (21.3±9.9) versus SMOKE (18.3±8.5). DISCUSSION: Tolerance to motion sickness was aided by short-term smoking deprivation, supporting Hypothesis (i) but not Hypothesis (ii). The effect was was approximately equivalent to half of the effect of an anti-motion sickness drug. Temporary nicotine withdrawal peri-operatively may explain why smokers have reduced risk for postoperative nausea and vomiting (PONV).

From dispersed to monopolized violence: expansion and consolidation of the Primeiro Comando da Capital's hegemony in São Paulo's prisons

The present work aims to understand the process of expansion and consolidation of the organized criminal group the Primeiro Comando da Capital (PCC) in São Paulo’s prison system over the past 20 years, and the social configuration that has formed as a result of the PCCs monopolization of opportunities of power. To this end, the work of Norbert Elias is utilized to analyze empirical data collected from various sources. The article consists of two lines of analysis. First, the PCC phenomenon is approached from a macro-sociological point of view, focusing on the social, political and administrative problems that are directly or indirectly linked to the PCCs social development. Second, a figurational analysis is used to explore the social dynamics produced from this process. In comparison to the “pre-PCC” situation, it is shown that the new social configuration produced from the hegemony of the PCC consists of a complexity of interdependencies, including greater functional division and social integration. Given this intensification of mutual dependencies, the social controls on individual behavior have been expanded and centralized. Here, the structure and organization of the PCC, its political dynamics, and individual self-control are central issues. The article concludes by calling into question the view that the most significant effect of the PCCs consolidation has been social pacification of São Paulo’s prison system. Fragilities in the power of the PCC are explored, principally the precarious nature of the relationship between the PCC and state authorities, and the extent to which the PCC’s authority is imposed.

Genetic programming for the minimum time swing up and balance control acrobot problem

This work describes how genetic programming is applied to evolving controllers for the minimum time swing up and inverted balance tasks of the continuous state and action: limited torque acrobot. The best swing-up controller is able to swing the acrobot up to a position very close to the inverted ‘handstand’ position in a very short time, shorter than that of Coulom (2004), who applied the same constraints on the applied torque values, and to take only slightly longer than the approach by Lai et al. (2009) where far larger torque values were allowed. The best balance controller is able to balance the acrobot in the inverted position when starting from the balance position for the length of time used in the fitness function in all runs; furthermore, 47 out of 50 of the runs evolve controllers able to maintain the balance position for an extended period, an improvement on the balance controllers generated by Dracopoulos and Nichols (2012), which this paper is extended from. The most successful balance controller is also able to balance the acrobot when starting from a small offset from the balance position for this extended period.