Sleep disorders, sleepiness and traffic safety: a public health menace

Sleep disorders are not uncommon and have been widely reported throughout the world. They have a profound impact on industrialized 24-h societies. Consequences of these problems include impaired social and recreational activities, increased human errors, loss of productivity, and elevated risk of accidents. Conditions such as acute and chronic insomnia, sleep loss, excessive sleepiness, shift-work, jet lag, narcolepsy, and sleep apnea warrant public health attention, since residual sleepiness during the day may affect performance of daily activities such as driving a car. Benzodiazepine hypnotics and zopiclone promote sleep, both having residual effects the following day including sleepiness and reduced alertness. In contrast, the non-benzodiazepine hypnotics zolpidem and zaleplon have no significant next-day residual effects when taken as recommended. Research on the effects of wakefulness-promoting drugs on driving ability is limited. Countermeasures for excessive daytime sleepiness have a limited effect. There is a need for a social awareness program to educate the public about the potential consequences of various sleep disorders such as narcolepsy, sleep apnea, shift-work-related sleep loss, and excessive daytime sleepiness in order to reduce the number of sleep-related traffic accidents.

Influence of gender on psychomotor vigilance task performance by adolescents

During adolescence, the sleep phase delay associated with early school times increases daytime sleepiness and reduces psychomotor performance. Some studies have shown an effect of gender on psychomotor performance in adults and children. Males present faster reaction times (RT) compared with females. The aim of the present study was to evaluate the influence of gender on Palm psychomotor vigilance task (PVT) performance in adolescents. Thirty-four adolescents (19 girls, 13 to 16 years old) attending morning school classes of a public school in Curitiba, PR, Brazil, participated in the study. Sleep patterns were measured using actigraphy and sleepiness data were accessed with the Karolinska Sleepiness Scale (KSS). KSS and PVT measurements were collected at two times in the morning (8:00 and 11:00 h). The data were compared using one-way ANOVA, considering gender as a factor. ANOVA indicated that gender did not affect sleep patterns and subjective somnolence; however, a statistically significant effect of gender was detected for PVT performance. Boys presented faster RT (RT-PVT1: 345.51 ms, F = 6.08, P < 0.05; RT-PVT2: 343.30 ms, F = 6.35, P < 0.05) and fewer lapses (lapses-PVT1: 8.71, F = 4.45, P < 0.05; lapses-PVT2: 7.82, F = 7.06, P < 0.05) compared with girls (RT-PVT1: 402.96; RT-PVT2: 415.70; lapses-PVT1: 16.33; lapses-PVT2: 17.80). These results showed that this effect of gender, already reported in adults and children, is also observed in adolescents. The influence of gender should be taken into account in studies that use Palm PVT to evaluate psychomotor performance in this age range.

Liberal versus neo-developmental convention to growth: why has Brazil shown a poor performance since the 1980s?

The main goal of our paper is to provide analytical arguments to explain why Brazil has not been able to restore its long-term capacity for economic growth, especially compared with its economy in the 1950-1979 period (7.3 per cent per year on average) or even with a select number of emerging economies in the 1980-2010 period(6.7 per cent per year on average, against 2.3 per cent per year on average in Brazil in the same period). We build our idea of convention to growth based on the Keynesian concept of convention. For our purposes, this concept could be briefly summarized as the way in which the set of public and private economic decisions related to different objectives, such as how much to produce and invest, how much to charge for products and services, how to finance public and private debt, how to finance research and development, and so on, are indefinitely - or at least until there is no change- carried out by the political, economic and social institutions. This analytical reference can be connected to the Neo-Schumpeterian National Innovation System (NIS) concept, which emphasizes not only institutions associated with science and technology per se, but also the complex interaction among them and other institutions. In this paper we identify two conventions to long-term growth in the last three decades in Brazil: the liberal and the neo-developmental. We show that the poor performance in the Brazilian economy in terms of real GDP growth from the 1980s on can be explained by a weak coordination between short-term macroeconomic policies and long-term industrial and technological policies. This weak coordination, in turn, can be associated with the prevalence of the liberal convention from the 1990s on, which has emphasized price stabilization to the detriment of a neo-developmental strategy whose primary goal is to sustain higher rates of growth and full employment in Brazil.