Development blocks in innovation networks : The Swedish manufacturing industry, 1970–2007

The notion of development blocks (Dahmén, 1950, 1991) suggests the co-evolution of technologies and industries through complementarities and the overcoming of imbalances. This study proposes and applies a methodology to analyse development blocks empirically. To assess the extent and character of innovational interdependencies between industries the study combines analysis of innovation biographies and statistical network analysis. This is made possible by using data from a newly constructed innovation output database for Sweden. The study finds ten communities of closely related industries in which innovation activity has been prompted by the emergence of technological imbalances or by the exploitation of new technological opportunities. The communities found in the Swedish network of innovation are shown to be stable over time and often characterized by strong user-supplier interdependencies. These findings serve to stress how historical imbalances and opportunities are key to understanding the dynamics of the long-run development of industries and new technologies

Recruitment of the Serratus Anterior as an Accessory Muscle of Ventilation During Graded Exercise

The role of the serratus anterior (SA) as an accessory muscle of ventilation and its physiologic significance under exercising conditions remains unclear. Recent investigations have utilized the measurement of SA as an analog for respiratory muscle oxygenation. The purpose of this investigation was to examine the action of the serratus anterior via surface electromyography (EMG) and near infrared spectroscopy (NIRS) during exercise while controlling for muscular effort not related to ventilation. Nine healthy volunteers (age = 24.4 ± 0.5 years, VO2max= 3.416 ± 0.35 l min−1; VEpeak = 127.5 ± 13.1 l min−1; TVpeak = 2.844 ± 0.226 l) completed a graded exercise test to volitional exhaustion on a cycle ergometer. The subjects’ arms were folded and relaxed at the abdomen to minimize muscular effort resulting from scapular stabilization during pushing/forward flexion of the arms associated with cycle ergometry. VO2 and VE were monitored breath-by-breath throughout exercise. EMG was recorded over the right SA, and a near infrared probe was placed over the left SA. No significant differences were observed throughout the graded exercise test for tissue oxygenation (StO2) (n = 6, F[1.532, 7.661] = 0.895, P \u3e 0.05, η2 = 0.15) or EMG (n = 9, F[1.594, 12.75] = 3.067, P \u3e 0.05, η2 = 0.27). Although the recruitment of the SA has been postulated to aid in ventilation in various postures and disease states, it is concluded that it shows little muscular effort in healthy subjects during upright cycling. Additional research is needed to conclude the pertinence of utilizing StO2 of the SA as an analog for respiratory muscle oxygenation