Associations between infant and toddler regulatory problems, childhood co-developing internalising and externalising trajectories, and adolescent depression, psychotic and borderline personality disorder symptoms

Background Early regulatory problems (RPs) are associated with childhood internalising and externalising symptoms. Internalising and externalising symptoms, in turn, are associated with adolescent psychopathology (e.g. personality disorders, depression). We examined whether RPs are directly associated with adolescent psychopathology, or whether associations are indirect via childhood internalising and externalising symptoms. Methods We used data from the Avon Longitudinal Study of Parents and Children. Mothers reported on their child's RPs at 6, 15–18 and 24–30 months, and internalising and externalising symptoms at 4, 7, 8 and 9.5 years. Adolescent psychotic, depression and BPD symptoms were assessed at 11–12 years. Children were grouped by their patterns of co‐developing internalising and externalising symptoms using parallel process latent class growth analysis (PP‐LCGA). Path analysis was used to examine direct and indirect associations from RPs to the three adolescent outcomes. Results There were four groups of children with distinct patterns of co‐developing internalising and externalising (INT/EXT) symptoms. Most children (53%) demonstrated low–moderate and stable levels of INT/EXT symptoms. A small proportion (7.7%) evidenced moderate and increasing INT and high stable EXT symptoms: this pattern was strongly predictive of adolescent psychopathology (e.g. depression at 11 years: unadjusted odds ratio = 5.62; 95% confidence intervals = 3.82, 8.27). The other two groups were differentially associated with adolescent outcomes (i.e. moderate–high increasing INT/moderate decreasing EXT predicted mother‐reported depression at 12, while low stable INT/moderate–high stable EXT predicted child‐reported depression at 11). In path analysis, RPs at each time‐point were significantly indirectly associated with symptoms of BPD and child‐ and mother‐reported depression symptoms via the most severe class of INT/EXT symptoms. Conclusions Consistent with a cascade model of development, RPs are predictive of higher levels of co‐developing INT/EXT symptoms, which in turn increase risk of adolescent psychopathology. Clinicians should be aware of, and treat, early RPs to prevent chronic psychopathology

Fractal Structure of Random Matrices

A multifractal analysis is performed on the universality classes of random matrices and the transition ones.Our results indicate that the eigenvector probability distribution is a linear sum of two chi-squared distribution throughout the transition between the universality ensembles of random matrix theory and Poisson

A new numerical approach to Anderson (de)localization

We develop a new approach for the Anderson localization problem. The implementation of this method yields strong numerical evidence leading to a (surprising to many) conjecture: The two dimensional discrete random Schroedinger operator with small disorder allows states that are dynamically delocalized with positive probability. This approach is based on a recent result by Abakumov-Liaw-Poltoratski which is rooted in the study of spectral behavior under rank-one perturbations, and states that every non-zero vector is almost surely cyclic for the singular part of the operator. The numerical work presented is rather simplistic compared to other numerical approaches in the field. Further, this method eliminates effects due to boundary conditions. While we carried out the numerical experiment almost exclusively in the case of the two dimensional discrete random Schroedinger operator, we include the setup for the general class of Anderson models called Anderson-type Hamiltonians. We track the location of the energy when a wave packet initially located at the origin is evolved according to the discrete random Schroedinger operator. This method does not provide new insight on the energy regimes for which diffusion occurs.Comment: 15 pages, 8 figure

A note on second-order perturbations of non-canonical scalar fields

We study second-order perturbations for a general non-canonical scalar field, minimally coupled to gravity, on the unperturbed FRW background, where metric fluctuations are neglected a priori. By employing different approaches to cosmological perturbation theory, we show that, even in this simplified set-up, the second-order perturbations to the stress tensor, the energy density and the pressure display potential instabilities, which are not present at linear order. The conditions on the Lagrangian under which these instabilities take place are provided. We also discuss briefly the significance of our analysis in light of the possible linearization instability of these fields about the FRW background.Comment: 8 page, Revtex 4. Clarifications added, results unchanged; [v3] 10 pages, matches with the published version, Discussion for specific cases expanded and preliminary results including the metric perturbations discusse

Large Scale Cross-Correlations in Internet Traffic

The Internet is a complex network of interconnected routers and the existence of collective behavior such as congestion suggests that the correlations between different connections play a crucial role. It is thus critical to measure and quantify these correlations. We use methods of random matrix theory (RMT) to analyze the cross-correlation matrix C of information flow changes of 650 connections between 26 routers of the French scientific network `Renater'. We find that C has the universal properties of the Gaussian orthogonal ensemble of random matrices: The distribution of eigenvalues--up to a rescaling which exhibits a typical correlation time of the order 10 minutes--and the spacing distribution follow the predictions of RMT. There are some deviations for large eigenvalues which contain network-specific information and which identify genuine correlations between connections. The study of the most correlated connections reveals the existence of `active centers' which are exchanging information with a large number of routers thereby inducing correlations between the corresponding connections. These strong correlations could be a reason for the observed self-similarity in the WWW traffic.Comment: 7 pages, 6 figures, final versio

CP Violation and Strong Phases from Penguins in B±→PP\bf B^{\pm}\rightarrow PP and B±→VP\bf B^{\pm}\rightarrow VP Decays

We calculate direct CP-violating rate asymmetries in charged $B\to PP$ and $B\to VP$ decays arising from the interference of amplitudes with different strong and CKM phases. The perturbative strong phases develop at order $\alpha_s$ from absorptive parts of one-loop matrix elements of the next-to-leading logarithm corrected effective Hamiltonian. CPT constraints are maintained. Based on this model, we find that partial rate asymmetries between charge conjugate $B^{\pm}$ decays can be as high as 20\% for certain channels with branching ratios in the $10^{-6}$ range. Because the $c\bar{c}$ threshold lies so close to the physical momentum scale, the asymmetries depend sensitively on the model assumptions used to evaluate the imaginary parts of the matrix elements, in particular, on the internal momentum transfer. The charge asymmetries of partial rates would provide unambiguous evidence for direct CP violation.Comment: 19 pages, 4 figures (3 available as uuencoded ps-files), LaTeX, preprint DESY 94-17

A Two-dimensional Superconductor in a Tilted Magnetic Field - new states with finite Cooper-pair momentum

Varying the angle Theta between applied field and the conducting planes of a layered superconductor in a small interval close to the plane-parallel field direction, a large number of superconducting states with unusual properties may be produced. For these states, the pair breaking effect of the magnetic field affects both the orbital and the spin degree of freedom. This leads to pair wave functions with finite momentum, which are labeled by Landau quantum numbers 0<n<\infty. The stable order parameter structure and magnetic field distribution for these states is found by minimizing the quasiclassical free energy near H_{c2} including nonlinear terms. One finds states with coexisting line-like and point-like order parameter zeros and states with coexisting vortices and antivortices. The magnetic response may be diamagnetic or paramagnetic depending on the position within the unit cell. The structure of the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) states at Theta=0 is reconsidered. The transition n->\infty of the paramagnetic vortex states to the FFLO-limit is analyzed and the physical reason for the occupation of higher Landau levels is pointed out.Comment: 24 pages, 11 figure

Ethnic differences translate to inadequacy of high-risk screening for gestational diabetes mellitus in an Asian population: a cohort study

Background: universal and high-risk screening for gestational diabetes mellitus (GDM) has been widely studied and debated. Few studies have assessed GDM screening in Asian populations and even fewer have compared Asian ethnic groups in a single multi-ethnic population.Methods: 1136 pregnant women (56.7% Chinese, 25.5% Malay and 17.8% Indian) from the Growing Up in Singapore Towards healthy Outcomes (GUSTO) birth cohort study were screened for GDM by 75-g oral glucose tolerance test (OGTT) at 26–28 weeks of gestation. GDM was defined using the World Health Organization (WHO) criteria. High-risk screening is based on the guidelines of the UK National Institute for Health and Clinical Excellence.Results: universal screening detected significantly more cases than high-risk screening [crude OR 2.2 (95% CI 1.7-2.8)], particularly for Chinese women [crude OR = 3.5 (95% CI 2.5-5.0)]. Pre-pregnancy BMI &gt; 30 kg/m2 (adjusted OR = 3.4, 95% CI 1.5-7.9) and previous GDM history (adjusted OR = 6.6, 95% CI 1.2-37.3) were associated with increased risk of GDM in Malay women while GDM history was the only significant risk factor for GDM in Chinese women (adjusted OR = 4.7, 95% CI 2.0-11.0).Conclusion: risk factors used in high-risk screening do not sufficiently predict GDM risk and failed to detect half the GDM cases in Asian women. Asian women, particularly Chinese, should be screened to avoid under-diagnosis of GDM and thereby optimize maternal and fetal outcome

The Paradoxical Effects of Chronic Intra-Amniotic Ureaplasma parvum Exposure on Ovine Fetal Brain Development

Chorioamnionitis is associated with adverse neurodevelopmental outcomes in preterm infants. Ureaplasma spp. are the microorganisms most frequently isolated from the amniotic fluid of women diagnosed with chorioamnionitis. However, controversy remains concerning the role of Ureaplasma spp. in the pathogenesis of neonatal brain injury. We hypothesize that re-exposure to an inflammatory trigger during the perinatal period might be responsible for the variation in brain outcome of preterms following Ureaplasma driven chorioamnionitis. To investigate these clinical scenarios, we performed a detailed multi-modal study in which ovine neurodevelopmental outcomes were assessed following chronic intra-amniotic Ureaplasma parvum (UP) infection, either alone or combined with subsequent lipopolysaccharide (LPS) exposure. We show that chronic intra-amniotic UP exposure during the second trimester provoked a decrease of astrocytes, increased oligodendrocyte numbers and elevated 5-methylcytosine levels. In contrast, short-term LPS exposure before preterm birth induced increased microglial activation, myelin loss, elevation of 5-hydroxymethylcytosine levels and lipid profile changes. These LPS-induced changes were prevented by chronic pre-exposure to UP (preconditioning). These data indicate that chronic UP exposure provokes dual effects on preterm brain development in utero. On one hand, prolonged UP exposure causes detrimental cerebral changes which may predispose to adverse postnatal clinical outcomes. On the other, chronic intra-amniotic UP exposure preconditions the brain against a second inflammatory hit. This study demonstrates that microbial interactions, timing and duration of inflammatory insults will determine the effects on the fetal brain. Therefore, this study helps to understand the complex and diverse postnatal neurological outcomes following UP driven chorioamnionitis

Nonorientable spacetime tunneling

Misner space is generalized to have the nonorientable topology of a Klein bottle, and it is shown that in a classical spacetime with multiply connected space slices having such a topology, closed timelike curves are formed. Different regions on the Klein bottle surface can be distinguished which are separated by apparent horizons fixed at particular values of the two angular variables that eneter the metric. Around the throat of this tunnel (which we denote a Klein bottlehole), the position of these horizons dictates an ordinary and exotic matter distribution such that, in addition to the known diverging lensing action of wormholes, a converging lensing action is also present at the mouths. Associated with this matter distribution, the accelerating version of this Klein bottlehole shows four distinct chronology horizons, each with its own nonchronal region. A calculation of the quantum vacuum fluctuations performed by using the regularized two-point Hadamard function shows that each chronology horizon nests a set of polarized hypersurfaces where the renormalized momentum-energy tensor diverges. This quantum instability can be prevented if we take the accelerating Klein bottlehole to be a generalization of a modified Misner space in which the period of the closed spatial direction is time-dependent. In this case, the nonchronal regions and closed timelike curves cannot exceed a minimum size of the order the Planck scale.Comment: 11 pages, RevTex, Accepted in Phys. Rev.