Prenatal parental representations: Influences on perceived romantic couple adjustment and infant's temperament during pregnancy and after the infant's birth

Objective: The present work aimed to evaluate the differences between fathers' and mothers' prenatal parental representations, the differences between pre- and postnatal perceptions of couple adjustment, and whether the quality of prenatal parental representations is associated with the perception of couple adjustment and with the perception of infant temperament at 3 months. Background: Within a multifactorial, transactional model, several studies indicated that prenatal parental representations are relevant to the quality of infant–parent relationship and the child's development. Method: Couples experiencing their first pregnancy (n = 40) (mothers: Mage = 33.7 years, SD = 5,1 years; fathers: (Mage = 37.4 years, SD = 5.6 years) responded to the Parental Representations Interview During Pregnancy and the Dyadic Adjustment Scale during the seventh month of pregnancy. When couples' infant was 3 months of age, the parents completed the Infant Behavior Questionnaire-R to assess infant temperament. Results: Analyses revealed that mothers and fathers who had an unbalanced and unintegrated parental representation perceived their couple adjustment as less cohesive, and this was related to a more negative perception of the child's temperament. Conclusions: Prenatal parental representations were found to be a significant variable in terms of their influence on the quality of pre- and postnatal parents' romantic couple adjustment and on the infant's temperament. Implications: It is important to include both mothers and fathers to further our understanding of parental influence on a child's development and to enhance the efficacy of preventive programs since pregnancy

Anisotropic charge dynamics in detwinned Ba(Fe1−x_{1-x}Cox_x)2_2As2_2

We investigate the optical conductivity as a function of temperature with light polarized along the in-plane orthorhombic $a$- and $b$-axes of Ba(Fe$_{1-x}$Co$_x$)$_2$As$_2$ for $x$=0 and 2.5$\%$ under uniaxial pressure. The charge dynamics at low frequencies on these detwinned, single domain compounds tracks the anisotropic $dc$ transport properties across their structural and magnetic phase transitions. Our findings allow us to estimate the dichroism, which extends to relatively high frequencies. These results are consistent with a scenario in which orbital order plays a significant role in the tetragonal-to-orthorhombic structural transition

Anisotropic in-plane optical conductivity in detwinned Ba(Fe1-xCox)2As2

We study the anisotropic in-plane optical conductivity of detwinned Ba(Fe1-xCox)2As2 single crystals for x=0, 2.5% and 4.5% in a broad energy range (3 meV-5 eV) across their structural and magnetic transitions. For temperatures below the Neel transition, the topology of the reconstructed Fermi surface, combined with the distinct behavior of the scattering rates, determines the anisotropy of the low frequency optical response. For the itinerant charge carriers, we are able to disentangle the evolution of the Drude weights and scattering rates and to observe their enhancement along the orthorhombic antiferromagnetic a-axis with respect to the ferromagnetic b-axis. For temperatures above Ts, uniaxial stress leads to a finite in-plane anisotropy. The anisotropy of the optical conductivity, leading to a significant dichroism, extends to high frequencies in the mid- and near-infrared regions. The temperature dependence of the dichroism at all dopings scales with the anisotropy ratio of the dc conductivity, suggesting the electronic nature of the structural transition. Our findings bear testimony to a large nematic susceptibility that couples very effectively to the uniaxial lattice strain. In order to clarify the subtle interplay of magnetism and Fermi surface topology we compare our results with theoretical calculations obtained from density functional theory within the full-potential linear augmented plane-wave method.Comment: 17 pages, 9 figure

First-Time Mothers’ and Fathers’ Developmental Changes in the Perception of Their Daughters’ and Sons’ Temperament: Its Association With Parents’ Mental Health

Objective: Most studies investigating the role of parenting behaviors on a child’s development are directed to mothers. However, recent analyses show that mothers and fathers have a different influence on a child’s functioning, specifically her/his temperament. The present study explored the developmental change of parents’ perception of their daughters’ and sons’ temperament and its association with parental mental health problems. Methods: The sample included 188 parents (94 couples) and their at-term 94 babies (55.3% boys, 44.7% girls). Assessments by self-reports were conducted at 3 (Time 1) and 12 (Time 2) months after the children’s birth; at Time 1, mothers and fathers independently answered: the State–Trait Anxiety Inventory (STAI), the Edinburgh Postnatal Depression Scale (EPDS), and the Infant Behavior Questionnaire (IBQ-R). At Time 2, EPDS, STAI, and IBQ-R were again administered to mothers and fathers. Results: In general, mothers and fathers would give similar descriptions of their child’s temperament throughout the first year of life; however, infant temperament showed developmental changes as well as gender differences. Mother and father anxiety and depression symptoms are associated with the infants’ negative affectivity. Also, mothers with high anxiety and depression levels perceive their infants with a minor tendency to approach novelty, to seek environmental stimulation, and to express/experience positive emotions. Conclusion: The results highlight the need to screen for infants’ temperament vulnerabilities in the context of maternal and paternal depression in order to protect the child from behavioral, cognitive, and emotional difficulties and to create specific programs aimed at preventing dysfunctional parent–infant relationships

Charge dynamics of the Co-doped BaFe2_2As2_2

We report on a thorough optical investigation over a broad spectral range and as a function of temperature of the charge dynamics in Ba(Co$_x$Fe$_{1-x}$)$_2$As$_2$ compounds for Co-doping ranging between 0 and 18%. For the parent compound as well as for $x$=0.025 we observe the opening of a pseudogap, due to the spin-density-wave phase transition and inducing a reshuffling of spectral weight from low to high frequencies. For compounds with 0.051$\le x \le$ 0.11 we detect the superconducting gap, while at $x$=0.18 the material stays metallic at all temperatures. We describe the effective metallic contribution to the optical conductivity with two Drude terms, representing the combination of a coherent and incoherent component, and extract the respective scattering rates. We establish that the $dc$ transport properties in the normal phase are dominated by the coherent Drude term for 0$\le x \le$0.051 and by the incoherent one for 0.061$\le x \le$0.18, respectively. Finally through spectral weight arguments, we give clear-cut evidence for moderate electronic correlations for 0$\le x \le$0.061, which then crossover to values appropriate for a regime of weak interacting and nearly-free electron metals for $x\ge$0.11

Chow's theorem and universal holonomic quantum computation

A theorem from control theory relating the Lie algebra generated by vector fields on a manifold to the controllability of the dynamical system is shown to apply to Holonomic Quantum Computation. Conditions for deriving the holonomy algebra are presented by taking covariant derivatives of the curvature associated to a non-Abelian gauge connection. When applied to the Optical Holonomic Computer, these conditions determine that the holonomy group of the two-qubit interaction model contains $SU(2) \times SU(2)$. In particular, a universal two-qubit logic gate is attainable for this model.Comment: 13 page

Mathematical Structure of Rabi Oscillations in the Strong Coupling Regime

In this paper we generalize the Jaynes--Cummings Hamiltonian by making use of some operators based on Lie algebras su(1,1) and su(2), and study a mathematical structure of Rabi floppings of these models in the strong coupling regime. We show that Rabi frequencies are given by matrix elements of generalized coherent operators (quant--ph/0202081) under the rotating--wave approximation. In the first half we make a general review of coherent operators and generalized coherent ones based on Lie algebras su(1,1) and su(2). In the latter half we carry out a detailed examination of Frasca (quant--ph/0111134) and generalize his method, and moreover present some related problems. We also apply our results to the construction of controlled unitary gates in Quantum Computation. Lastly we make a brief comment on application to Holonomic Quantum Computation.Comment: Latex file, 24 pages. I added a new section (Quantum Computation), so this paper became self-contained in a certain sens

Theoretical Investigation of Optical Conductivity in Ba [Fe(1-x)Co(x)]2 As2

We report on theoretical calculations of the optical conductivity of Ba [Fe(1-x)Co(x)]2 As2, as obtained from density functional theory within the full potential LAPW method. A thorough comparison with experiment shows that we are able to reproduce most of the observed experimental features, in particular a magnetic peak located at about 0.2 eV which we ascribe to antiferromagnetic ordered magnetic stripes. We also predict a large in-plane anisotropy of this feature, which agrees very well with measurements on detwinned crystals. The effect of Co doping as well as the dependence of plasma frequency on the magnetic order is also investigated