Anesthetic action on the transmission delay between cortex and thalamus explains the beta-buzz observed under propofol anesthesia

In recent years, more and more surgeries under general anesthesia have been performed with the assistance of electroencephalogram (EEG) monitors. An increase in anesthetic concentration leads to characteristic changes in the power spectra of the EEG. Although tracking the anesthetic-induced changes in EEG rhythms can be employed to estimate the depth of anesthesia, their precise underlying mechanisms are still unknown. A prominent feature in the EEG of some patients is the emergence of a strong power peak in the β–frequency band, which moves to the α–frequency band while increasing the anesthetic concentration. This feature is called the beta-buzz. In the present study, we use a thalamo-cortical neural population feedback model to reproduce observed characteristic features in frontal EEG power obtained experimentally during propofol general anesthesia, such as this beta-buzz. First, we find that the spectral power peak in the α– and δ–frequency ranges depend on the decay rate constant of excitatory and inhibitory synapses, but the anesthetic action on synapses does not explain the beta-buzz. Moreover, considering the action of propofol on the transmission delay between cortex and thalamus, the model reveals that the beta-buzz may result from a prolongation of the transmission delay by increasing propofol concentration. A corresponding relationship between transmission delay and anesthetic blood concentration is derived. Finally, an analytical stability study demonstrates that increasing propofol concentration moves the systems resting state towards its stability threshold

Leveraging the macro-level environment to balance work and life: an analysis of female entrepreneurs' job satisfaction

This study investigates the interactive effect of female entrepreneurs’ experience of work–life imbalance and gender-egalitarian macro-level conditions on their job satisfaction, with the prediction that the negative linear relationship between work–life imbalance and job satisfaction may be buffered by the presence of women-friendly action resources, emancipative values, and civic entitlements. Data pertaining to 7,392 female entrepreneurs from 44 countries offer empirical support for these predictions. Female entrepreneurs who are preoccupied with their ability to fulfill both work and life responsibilities are more likely to maintain a certain level of job satisfaction, even if they experience significant work–life imbalances, to the extent that they operate in supportive macro-level environments