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In this study, we investigated the physiological regulation of vagal tone during dyadic and triadic parent-infant interactions in infants born before or around the COVID-19 lockdown in Switzerland. We hypothesized that there would be a decrease in vagal tone in triadic interactions compared with dyadic interactions, as triadic interactions are more complex and therefore more resource demanding. However, we expected this difference to be smaller for infants who experienced the period of confinement, as the lockdown led parents to spend more time at home. We also hypothesized that parents would have less stressful interactional events in the triadic interaction because they would be used to interacting with the child together. This study included 36 parents with their 3 month-old infants. Eighteen families met the study authors before the onset of the pandemic (pre-COVID) and 18 met them after its onset, having experienced a period of confinement during the infants' first 3 months of life (COVID). Results showed that the COVID group had no decrease in vagal tone during triadic interactions, whereas the pre-COVID group did. This difference could not, however, be explained by less stressful interactional events in triadic interactions, as the COVID group showed more stressful interactional events in mother-father-infant interactions.  相似文献   
213.
We use a French firm‐level data set containing 13,000 firms over the period 1994–2004 to analyze the relationship between credit constraints and firms’ R&D behavior over the business cycle. Our main results can be summarized as follows: (i) R&D investment is countercyclical without credit constraints, but it becomes procyclical as firms face tighter credit constraints; (ii) this result is only observed for firms in sectors that depend more heavily upon external finance, or that are characterized by a low degree of asset tangibility; (iii) in more credit‐constrained firms, R&D investment plummets during recessions but does not increase proportionally during upturns.  相似文献   
214.
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