Predictors of Father-Child and Mother-Child Attachment in Two-Parent Families

The attachment of a child and his or her caregiver is a bond that helps tie them together emotionally. The most important principle of attachment theory is the need of a child to develop a relationship with at least one primary caregiver for healthy emotional and social development to occur. The majority of attachment research has focused primarily on mother-child attachment, minimizing fathers\u27 contributions to attachment. The current study examined attachment of both mothers and fathers in two-parent families. Research questions focused on the relationship between mother-child attachment and father-child attachment, the relationship between child temperament and father-child attachment security, and whether the amount of time each parent is away from his/her child predicts attachment security. The participants in this study consisted of 50 sets of parents (100 participants) who had at least one child between the ages of 3-5. The relationship between father-child and mother-child attachment was not significant. Likewise, the relationship between child temperament and parent-child attachment was not significant. Also, parents\u27 time away from their child was not a significant predictor of attachment. Further research is needed with more ethnicities and cultures represented; a more balanced sample of economic classes; mothers who work more hours outside of the home; and the use of more impartial, third party observation measures to assess attachment and child temperament

Generation of millijoule-level soft-x-ray laser pulses at a 4-Hz repetition rate in a highly saturated tabletop capillary discharge amplifier

Includes bibliographical references (page 1117).Laser pulses with energies of as much as 1 mJ were generated at a wavelength of 46.9 nm by single-pass amplification in a 34.5 cm-long Ne-like Ar capillary discharge plasma. The large gain-length product of this plasma column allows for soft-x-ray amplification in a highly saturated regime, resulting inefficient energy extraction. Average laser output pulse energy of 0.88 mJ and peak power of 0.6 MW were obtained at a repetition rate of 4 Hz. With an estimated peak spectral brightness of ≈1 × 1023 photons/s mm2 mrad2 0.01% bandwidth) this tabletop laser is one of the brightest soft-x-ray sources to date

Perturbing integrin function inhibits microtubule growth from centrosomes, spindle assembly, and cytokinesis

In many mammalian cell types, integrin-mediated cell-matrix adhesion is required for the G1–S transition of the cell cycle. As cells approach mitosis, a dramatic remodeling of their cytoskeleton accompanies dynamic changes in matrix adhesion, suggesting a mechanistic link. However, the role of integrins in cell division remains mostly unexplored. Using two cellular systems, we demonstrate that a point mutation in the β1 cytoplasmic domain (β1 tail) known to decrease integrin activity supports entry into mitosis but inhibits the assembly of a radial microtubule array focused at the centrosome during interphase, the formation of a bipolar spindle at mitosis and cytokinesis. These events are restored by externally activating the mutant integrin with specific antibodies. This is the first demonstration that the integrin β1 tail can regulate centrosome function, the assembly of the mitotic spindle, and cytokinesis

Measurement of the spatial coherence buildup in a discharge pumped table-top soft x-ray laser

Includes bibliographical references (page 2802).We have measured the variation of the spatial coherence with plasma column length in a saturated table-top 46.9-nm Ne-like Ar capillary discharge soft x-ray amplifier for lengths up to 16.4 cm. The measurements, which are in good agreement with time dependent wave-optics model computations, provide the first experimental evidence of a monotonic increase of the coherence with length in a soft x-ray amplifier. The variation of the coherence across the beam profile was also studied. Off axis, the coherence is larger in the tangential than in the radial direction

Focusing of a tabletop soft-x-ray laser beam and laser ablation

Includes bibliographical references (page 1716).We focused the beam of a high-repetition-rate capillary-discharge tabletop laser operating at a wavelength of 46.9 nm, using a spherical Si/Sc multilayer mirror. The energy densities significantly exceeded the thresholds for the ablation of metals. Single-shot laser ablation patterns were used in combination with ray-tracing computations to characterize the focused beam. The radiation intensity within the 2-μm-diameter central region of the focal spot was estimated to be ≈1011 W/cm2, with a corresponding energy density of ~100 J/cm2