Intrusive parenting in early childhood: A review and meta-analysis.

This systematic review and meta-analysis examines similarities and differences in intrusive parenting between mothers and fathers and relations between intrusive parenting and early childhood development. The authors integrated 55 studies and differentiated cognitive skills and socio-emotional problems as developmental outcomes. The present study employs three-level meta-analyses to reliably estimate effect sizes and examine a range of moderators. It finds a moderate effect size of similarities in intrusive parenting within a family (r = 0.256, confidence interval [CI] = [0.180, 0.329]). No significant differences were observed in intrusiveness level between mothers and fathers (g = 0.035, CI = [-0.034, 0.103]). Intrusive parenting had a significant positive association with children's socio-emotional problems (rmother  = 0.098, CImother  = [0.051, 0.145]; rfather  = 0.094, CI father  = [0.032, 0.154]) but was not related to cognitive skills. Moderator analyses suggest that East Asian mothers exhibit higher intrusiveness levels than fathers, whereas Western parents display no significant differences. Overall, these results reveal more similarities than differences in intrusive parenting and that culture likely plays a role in shaping gender-specific parenting behaviors.

Grandmothers are part of the parenting network, too! A longitudinal study on coparenting, maternal sensitivity, child attachment and behavior problems in a Chinese sample.

Grandmothers are important in Chinese families. This study explored the early emerging mother-grandmother-infant network and its association with child's socioemotional development in multigenerational families in a non-WEIRD country. The analytic sample included 60 children (T1: Mage  = 6.5 months) and their caregivers residing in Beijing. Measures used were the Strange Situation Procedure (SSP), the Lausanne Trilogue Play (LTP), the Maternal Behavior Q-Sort (MBQS), and the Infant-Toddler Social and Emotional Assessment. Structural equation and path modeling revealed that (1) more grandmaternal neutral/watching coparenting behaviors at the first assessment were related to more secure infant-mother attachment relationships at the second assessment (T2: Mage  = 1 year); (2) maternal sensitivity at T2 was a partial mediator between earlier undermining and neutral/watching coparenting behaviors and young children's externalizing problems at the final assessment (T3: Mage  = 2 years). Findings are discussed in terms of the roles played by mother-grandmother coparenting network in the children's socioemotional development.

High-finesse cavity external optical feedback DFB laser with hertz relative linewidth.

We report hertz level relative linewidth distributed feedback diode lasers with external optical feedback from a high finesse F-P cavity, and demonstrate the efficient phase noise suppression and laser linewidth reduction of the optical feedback technique. The laser phase noise is dramatically suppressed throughout the measurement frequency range. Especially at the Fourier frequency of 17 kHz, approximately the linewidth of the F-P reference cavity, the laser phase noise is significantly suppressed by more than 92 dB. Above this Fourier frequency, the noise maintains a white phase noise plateau as low as -124.4 dBc/Hz. The laser's FWHM linewidth is reduced from 7 MHz to 4.4 Hz, and its instantaneous linewidth is 220 mHz in the Lorentzian fitting.

Operating a (87)Sr optical lattice clock with high precision and at high density.

We describe recent experimental progress with the JILA Sr optical frequency standard, which has a systematic uncertainty at the 10-(16) fractional frequency level. An upgraded laser system has recently been constructed in our lab which may allow the JILA Sr standard to reach the standard quantum measurement limit and achieve record levels of stability. To take full advantage of these improvements, it will be necessary to operate a lattice clock with a large number of atoms, and systematic frequency shifts resulting from atomic interactions will become increasingly important. We discuss how collisional frequency shifts can arise in an optical lattice clock employing fermionic atoms and describe a novel method by which such systematic effects can be suppressed.

Suppression of collisional shifts in a strongly interacting lattice clock.

Optical lattice clocks with extremely stable frequency are possible when many atoms are interrogated simultaneously, but this precision may come at the cost of systematic inaccuracy resulting from atomic interactions. Density-dependent frequency shifts can occur even in a clock that uses fermionic atoms if they are subject to inhomogeneous optical excitation. However, sufficiently strong interactions can suppress collisional shifts in lattice sites containing more than one atom. We demonstrated the effectiveness of this approach with a strontium lattice clock by reducing both the collisional frequency shift and its uncertainty to the level of 10(-17). This result eliminates the compromise between precision and accuracy in a many-particle system; both will continue to improve as the number of particles increases.