COVID-19 first lockdown as a window into language acquisition: Associations between caregiver-child activities and vocabulary gains

The COVID-19 pandemic, and the resulting closure of daycare centers worldwide, led to unprecedented changes in children’s learning environments. This period of increased time at home with caregivers, with limited access to external sources (e.g., daycares) provides a unique opportunity to examine the associations between the caregiver-child activities and children’s language development. The vocabularies of 1742 children aged8-36 months across 13 countries and 12 languages were evaluated at the beginning and end of the first lockdown period in their respective countries(from March to September 2020). Children who had less passive screen exposure and whose caregivers read more to them showed larger gains in vocabulary development during lockdown, after controlling for SES and other caregiver-child activities. Children also gained more words than expected (based on normative data) during lockdown; either caregivers were more aware of their child’s development or vocabulary development benefited from intense caregiver-child interaction during lockdown

Verb generalization of preschool-aged children, experimental data 2018-2019

This study investigated whether seeing iconic gestures depicting verb referents promotes two types of generalization. We taught 3-4-year-olds novel locomotion verbs. Children who saw iconic manner gestures during training generalized more verbs to novel events (first-order generalization) than children who saw interactive gestures (Exp. 1, N = 48; Exp. 2, N = 48) and path-tracing gestures (Exp. 3, N = 48). Furthermore, immediately (Exp. 1 & 3) and after one week (Exp. 2), the iconic manner gesture group outperformed the control groups in subsequent generalization trials with different novel verbs (second-order generalization), although all groups saw interactive gestures. Thus, seeing iconic gestures that depict verb referents helps children (1) generalize individual verb meanings to novel events and (2) learn more verbs from the same sub-category. People naturally produce gestures when they speak. Little is still known about the role these gestures play in children's language development. My research focused on the role of iconic gestures - gesticulations that accompany speech and illustrate what is being said. For instance, you can wiggle your index and middle fingers to depict "walking" or bring your hand to your mouth as if holding a glass to depict "drinking". Children understand these iconic gestures by age 3 and my PhD research suggested that seeing adults produce these gestures while speaking is formative for children's language learning. Studying the ways we can stimulate vocabulary growth in preschool-aged children is very important, because the vocabulary size and skills of children at this age are major predictors of later school success. During the fellowship, I will collect data from one experiment with 3-year-old children that will help us to better understand how seeing iconic gestures facilitates word learning. I will visit local nurseries to play a computer-based word learning game with 96 children. I will publish my research findings from this experiment and from my PhD dissertation in two top-tier scientific journals in developmental psychology and I will present those research findings at one international conference on cognitive development, in Budapest, Hungary. I will also develop a Leverhulme Postdoctoral Fellowship proposal that extends my PhD research. I will design a series of lab-based experiments that help us investigate how parents can use nonverbal communication (e.g. facial expressions, body language, and hand gestures) to teach their child new words. I will propose to analyse body position of the parent and child (face-to-face or side-by-side) and eye contact, touch, and gestures. Moreover, I will visit two internationally leading research groups to develop collaborative research on mother-child interactions. I will visit Simone Pika's biocognition lab, which has collected video recordings of naturalistic social interactions between chimpanzee mothers and their young living in the wild. I will also visit with Susan Goldin-Meadow's gesture lab, which has collected video recordings of naturalistic interactions between parents and children in their family homes.</p

Interaction of adhered beryllium proxy dust with transient and stationary plasmas

Tungsten (W) substrates with adhered beryllium (Be) proxy dust - copper, chromium, aluminium - have been exposed in the Magnum-PSI linear device. Their interaction with transient and stationary plasmas has been systematically studied under varying heat fluxes and magnetic field topologies. The dust remobilization activities, macro-morphological changes and chemical modifications induced by the plasma incidence are documented. Aluminium is identified to be the most suitable surrogate material due to the similar binary phase diagram and nearly identical evaporation rates. Extrapolation suggests that Be dust cannot survive on hot W surfaces but it can trigger mixed Be/W effects prior to its plasma removal

An analytical force balance model for dust particles with size up to several Debye lengths

\u3cp\u3eIn this study, we developed a revised stationary force balance model for particles in the regime a/λD&lt;10. In contrast to other analytical models, the pressure and dipole force were included too, and for anisotropic plasmas, a novel contribution to the dipole moment was derived. Moreover, the Coulomb logarithm and collection cross-section were modified. The model was applied on a case study where carbon dust is formed near the plasma sheath in the linear plasma device Pilot-PSI. The pressure force and dipole force were found to be significant. By tracing the equilibrium position, the particle radius was determined at which the particle deposits. The obtained particle radius agrees well with the experimentally obtained size and suggests better agreement as compared to the unrevised model.\u3c/p\u3

Interaction of adhered beryllium proxy dust with transient and stationary plasmas

Tungsten (W) substrates with adhered beryllium (Be) proxy dust - copper, chromium, aluminium - have been exposed in the Magnum-PSI linear device. Their interaction with transient and stationary plasmas has been\u3cbr/\u3esystematically studied under varying heat fluxes and magnetic field topologies. The dust remobilization activities, macro-morphological changes and chemical modifications induced by the plasma incidence are documented. Aluminium is identified to be the most suitable surrogate material due to the similar binary phase diagram and nearly identical evaporation rates. Extrapolation suggests that Be dust cannot survive on hot W surfaces but it can trigger mixed Be/W effects prior to its plasma removal

An analytical force balance model for dust particles with size up to several Debye lengths

In this study, we developed a revised stationary force balance model for particles in the regime a/labda D&lt;10. In contrast to other analytical models, the pressure and dipole force were included too, and for anisotropic plasmas, a novel contribution to the dipole moment was derived. Moreover, the Coulomb logarithm and collection cross-section were modified. The model was applied on a case study where carbon dust is formed near the plasma sheath in the linear plasma device Pilot-PSI. The pressure force and dipole force were found to be significant. By tracing the equilibrium position, the particle radius was determined at which the particle deposits. The obtained particle radius agrees well with the experimentally obtained size and suggests better agreement as compared to the unrevised model.</p