The role of negative maternal affective states and infant temperament in early interactions between infants with cleft lip and their mothers

OBJECTIVES: The study examined the early interaction between mothers and their infants with cleft lip, assessing the role of maternal affective state and expressiveness and differences in infant temperament. METHODS: Mother-infant interactions were assessed in 25 2-month-old infants with cleft lip and 25 age-matched healthy infants. Self-report and behavioral observations were used to assess maternal depressive symptoms and expressions. Mothers rated infant temperament. RESULTS: Infants with cleft lip were less engaged and their mothers showed more difficulty in interaction than control group dyads. Mothers of infants with cleft lip displayed more negative affectivity, but did not report more self-rated depressive symptoms than control group mothers. No group differences were found in infant temperament. CONCLUSIONS: In order to support the mother's experience and facilitate her ongoing parental role, findings highlight the importance of identifying maternal negative affectivity during early interactions, even when they seem have little awareness of their depressive symptoms

Selective mass scaling for distorted solid-shell elements in explicit dynamics: optimal scaling factor and stable time step estimate

The use of solid-shell elements in explicit dynamics has been so far limited by the small critical time step resulting from the small thickness of these elements in comparison with the in-plane dimensions. To reduce the element highest eigenfrequency in inertia dominated problems, the selective mass scaling approach previously proposed in [G. Cocchetti, M. Pagani and U. Perego, Comp. \& Struct. 2013; 127:39-52.] for parallelepiped elements is here reformulated for distorted solid-shell elements. The two following objectives are achieved: the critical time step is governed by the smallest element in-plane dimension and not anymore by the thickness; the mass matrix remains diagonal after the selective mass scaling. The proposed approach makes reference to one Gauss point, trilinear brick element, for which the maximum eigenfrequency can be computed analytically. For this element, it is shown that the proposed mass scaling can be interpreted as a geometric thickness scaling, obtaining in this way a simple criterion for the definition of the optimal mass scaling factor. A strategy for the effective computation of the element maximum eigenfrequency is also proposed. The considered mass scaling preserves the element translational inertia, while it modifies the rotational one, leading to errors in the kinetic energy when the motion rotational component is dominant. The error has been rigorously assessed for an individual element, and a simple formula for its estimate has been derived. Numerical tests, both in small and large displacements and rotations, using a state-of-the-art solid-shell element taken from the literature, confirm the effectiveness and accuracy of the proposed approach. Copyright {\copyright} 2014 John Wiley \& Sons, Ltd

Cohesive crack approach to debonding analysis

Debonding of coatings from substrate due to coating compression occurs in many engineering applications. A simplified analytical approach for the estimation of the ultimate coating compression leading to debonding is developed in this paper, assuming an assigned out-of-plane defect of the coating. The formulation is based on the solution of a beam on a Pasternak (two parameters) elastic foundation, and on the assumption of a Mode I cohesive failure of the coating-substrate interface. The resulting formulas are simple and require the knowledge of a limited number of parameters

A linear optical coupler for cryogenic detectors

Abstract We present an improved version of a linear low-noise optical coupler having differential input and capable of driving a twisted cable to long distances, avoiding ground loops and electromagnetic interference. Owing to device optimization, this circuit version is able to be fast. Its frequency bandwidth is about 900 kHz, more than ten times larger than our previous implementation. The optical coupler presented is therefore suitable to be used with most of the applications with cryogenic detectors

Neutron star binary orbits in their host potential: Effect on early R-process enrichment

Coalescing neutron star binary (NSB) systems are primary candidates for r-process enrichment of galaxies. The recent detection of r-process elements in ultrafaint dwarf (UFD) galaxies and the abundances measured in classical dwarfs challenges the NSB merger scenario both in terms of coalescence time-scales and merger locations. In this paper, we focus on the dynamics of NSBs in the gravitational potentials of different types of host galaxies and on its impact on the subsequent galactic enrichment. We find that, for a ∼t−1 delay time distribution, even when receiving a low kick (∼10 km s−1) from the second supernova explosion, in shallow dwarf galaxy potentials NSBs tend to merge with a large off-set from the host galaxy. This results in a significant geometrical dilution of the amount of produced r-process elements that fall back and pollute the host galaxy gas reservoir. The combination of dilution and small number statistics produces a large scatter in the expected r-process enrichment within a single UFD or classical dwarf galaxy. Comparison between our results and observed europium abundances reveals a tension that even a systematic choice of optimistic parameters in our models cannot release. Such a discrepancy could point to the need of additional r-process production sites that suffer less severe dilution or to a population of extremely fast merging binaries

Molecular communications in complex systems of dynamic supramolecular polymers

Supramolecular polymers are composed of monomers that self-assemble non-covalently, generating distributions of monodimensional fibres in continuous communication with each other and with the surrounding solution. Fibres, exchanging molecular species, and external environment constitute a sole complex system, which intrinsic dynamics is hard to elucidate. Here we report coarse-grained molecular simulations that allow studying supramolecular polymers at the thermodynamic equilibrium, explicitly showing the complex nature of these systems, which are composed of exquisitely dynamic molecular entities. Detailed studies of molecular exchange provide insights into key factors controlling how assemblies communicate with each other, defining the equilibrium dynamics of the system. Using minimalistic and finer chemically relevant molecular models, we observe that a rich concerted complexity is intrinsic in such self-assembling systems. This offers a new dynamic and probabilistic (rather than structural) picture of supramolecular polymer systems, where the travelling molecular species continuously shape the assemblies that statistically emerge at the equilibrium