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Recent proposals suggest early adversity sets in motion particularly chronic and neurobiologically distinct trajectories of internalizing symptoms. However, few prospective studies in high-risk samples delineate distinct trajectories of internalizing symptoms from preschool age onward. We examined trajectories in a high-risk cohort, oversampled for internalizing symptoms, several preschool risk/maintenance factors, and school-age outcomes. Parents of 325 children completed the Strengths and Difficulties Questionnaire on up to four waves of data collection from preschool (3–5 years) to school age (8–9 years) and Preschool Age Psychiatric Assessment interviews at both ages. Multi-informant data were collected on risk factors and symptoms. Growth mixture modelling identified four trajectory classes of internalizing symptoms with stable low, rising low-to-moderate, stable moderate, and stable high symptoms. Children in the stable high symptom trajectory manifested clinically relevant internalizing symptoms, mainly diagnosed with anxiety disorders/depression at preschool and school age. Trajectories differed regarding loss/separation experience, maltreatment, maternal psychopathology, temperament, and stress-hormone regulation with loss/separation, temperament, maternal psychopathology, and stress-hormone regulation (trend) significantly contributing to explained variance. At school age, trajectories continued to differ on symptoms, disorders, and impairment. Our study is among the first to show that severe early adversity may trigger a chronic and neurobiologically distinct internalizing trajectory from preschool age onward.
Depression and obesity are highly prevalent, and major impacts on public health frequently co-occur. Recently, we reported that having depression moderates the effect of the FTO gene, suggesting its implication in the association between depression and obesity.
To confirm these findings by investigating the FTO polymorphism rs9939609 in new cohorts, and subsequently in a meta-analysis.
The sample consists of 6902 individuals with depression and 6799 controls from three replication cohorts and two original discovery cohorts. Linear regression models were performed to test for association between rs9939609 and body mass index (BMI), and for the interaction between rs9939609 and depression status for an effect on BMI. Fixed and random effects meta-analyses were performed using METASOFT.
In the replication cohorts, we observed a significant interaction between FTO, BMI and depression with fixed effects meta-analysis (β=0.12, P = 2.7 × 10−4) and with the Han/Eskin random effects method (P = 1.4 × 10−7) but not with traditional random effects (β = 0.1, P = 0.35). When combined with the discovery cohorts, random effects meta-analysis also supports the interaction (β = 0.12, P = 0.027) being highly significant based on the Han/Eskin model (P = 6.9 × 10−8). On average, carriers of the risk allele who have depression have a 2.2% higher BMI for each risk allele, over and above the main effect of FTO.
This meta-analysis provides additional support for a significant interaction between FTO, depression and BMI, indicating that depression increases the effect of FTO on BMI. The findings provide a useful starting point in understanding the biological mechanism involved in the association between obesity and depression.
New oral treatments are needed for all forms of leishmaniasis. Here, the improved oral efficacy of quercetin (Qc) and its penta-acetylated derivative (PQc) was evaluated in cutaneous leishmaniasis after encapsulation in lipid-core nanocapsules (LNCs) of poly(ε-caprolactone). Leishmania amazonensis-infected BALB/c mice were given 51 daily oral doses of free drugs (16 mg kg−1) or LNC-loaded drugs (0·4 mg kg−1). While treatment with free Qc reduced the lesion sizes and parasite loads by 38 and 71%, respectively, LNC-Qc produced 64 and 91% reduction, respectively. The antileishmanial efficacy of PQc was similar but not as potently improved by encapsulation as Qc. None of the treatments increased aspartate aminotransferase, alanine aminotransferase or creatinine serum levels. These findings indicate that when encapsulated in LNC, Qc and, to a lesser extent, PQc can safely produce an enhanced antileishmanial effect even at a 40-fold lower dose, with implications for the development of a new oral drug for cutaneous leishmaniasis.
We present the preliminary results of an 8-month monitoring campaign carried out on 6 AGN during the period December 1991 – July 1992. All but one of our targets showed continuum and/or line variability. The data were obtained using the 2D-Prutti + Cassegrain spectrograph at the CTIO 1.0-m telescope, and reduced following standard procedures. The slit width was 5″ and the nuclear spectra were extracted in a 10″ aperture. The wavelength coverage is 3500–7200Å, with 8Å resolution. The data were flux calibrated using standard stars and then normalized using the [O III] λ5007Å line flux for each object. NGC 6814: our spectra reveal that this object is still in a low state of activity and within the S/N ratio of our data, no variability was observed during this campaign. The stellar population is dominant in the nuclear spectrum and a synthesis using the star cluster library of Bica (1988) indicates a mainly old (∼ 86% of the continuum flux at 5870Å due to a population with age ≥ 10 Gyr), [Z/Z⊙] ≥ 0.3 stellar content, with an intrinsic reddening of E(B–V)=0.20. NGC 3227: using an off-nuclear spectrum corresponding to the two 5″×10″ regions 20.4″ E/W of the nucleus, we obtained also a mainly old (77% at 5870Å with age ≥ 10 Gyr), [Z/Z⊙]=0.3) synthetic stellar population, which contributes ∼ 43% of the nuclear light at 5600Å. The cross correlation of the 4245Å continuum and Hβ light curves results in a 18±3 -day lag. IC 4329A: our data show evidence of variability as a slow and constant increase in both continuum and lines fluxes, but no isolated event was detected. ESO141-G55: the light curves show small variations in the continuum, but no noticeable line variability. Akn 120 and Fairall 9: the data consists of two sets of spectra, separated by ∼ 6 months. Within each set little or no variability was detected, but strong line and continuum variations occurred between them.
Observational evidences of dust in the nuclear region of AGNs are substantial (Rudy 1984, ApJ, 284, 33; Jones et al. 1984, PASP, 96, 692). The ionization cones observed in several Seyfert galaxies has been interpreted as shadowing effects by a dust obscuring torus which hides the broad emission line region (BLR) and the central source (Wilson 1992; Storchi-Bergmann, Mulchaey and Wilson 1992, ApJ 395, L73). A large sample of optical and far-IR data for IRAS Seyfert galaxies has been analysed together with dust emission models (Bonatto and Pastoriza 1993), where it has been concluded that the same dust emission model can be applied to both Seyfert types. In order to further study the effects of dust in the spectra of active galactic nuclei, we have obtained spectrophotometry of 21 IRAS Seyfert galaxies in the range 3500–7200 Å and analyse them in conjuction with their IRAS fluxes. The stellar population type is derived from comparisons with normal galaxy templates using dilution effects in the K CaII line as discriminator. For 55% of the sample the population is of late type. For the rest, blue continua due to recent star formation and/or power-law may amount up to 30% at 4000Å. We conclude that the bulge stellar populations of IRAS Seyfert galaxies are similar to those of normal spirals, except that they are more reddened by E(B-V)i ∼ 0.20. Population-subtracted emission line ratios indicate on average stronger reddening for the narrow-line region (E(B-V)l ∼ 0.8. From photoionization models a power-law index for the ionizing continuum α=1.5, and a metallicity larger than solar are obtained. The most luminous IRAS galaxy of the sample (IRAS555) is discuss in detail: in order to be compatible with the observed IRAS fluxes and the optical stellar continuum, the ionizing continuum must be reddened by AV > 10 magnitudes. Consequently a dust structure in this galaxy appears to be increasingly affecting stars and gas towards the galaxy center.
The cubic polytype of silicon carbide is a stimulating candidate for Micro-Electro-Mechanical-Systems (MEMS) applications due to its interesting physical and chemical properties. Recently, we demonstrated the possibility to elaborate 3C-SiC membranes on 3C-SiC pseudo-substrates, using a silicon epilayer grown by Low Pressure Chemical Vapor Deposition as a sacrificial layer. Such structures could be the starting point for the elaboration of new MEMS devices. However, the roughness still represents a major concern. Therefore, in this contribution, we investigate the influence of an excimer laser irradiation on the Si epilayer surface prior to the 3C-SiC epilayer growth. We compare these results with the 3C-SiC epilayer grown directly on the as-grown Si epilayer.
An accurate cartesian method is devised to simulate incompressible viscous flows past an arbitrary moving body. The Navier-Stokes equations are spatially discretized onto a fixed Cartesian mesh. The body is taken into account via the ghost-cell method and the so-called penalty method, resulting in second-order accuracy in velocity. The accuracy and the efficiency of the solver are tested through two-dimensional reference simulations. To show the versatility of this scheme we simulate a three-dimensional self propelled jellyfish prototype.
Fish consumption is the major dietary source of EPA and DHA, which according to rodent experiments may reduce body fat mass and prevent obesity. Only a few human studies have investigated the association between fish consumption and body-weight gain. We investigated the association between fish consumption and subsequent change in body weight. Women and men (n 344 757) participating in the European Prospective Investigation into Cancer and Nutrition were followed for a median of 5·0 years. Linear and logistic regression were used to investigate the associations between fish consumption and subsequent change in body weight. Among women, the annual weight change was 5·70 (95 % CI 4·35, 7·06), 2·23 (95 % CI 0·16, 4·31) and 11·12 (95 % CI 8·17, 14·08) g/10 g higher total, lean and fatty fish consumption per d, respectively. The OR of becoming overweight in 5 years among women who were normal weight at enrolment was 1·02 (95 % CI 1·01, 1·02), 1·01 (95 % CI 1·00, 1·02) and 1·02 (95 % CI 1·01, 1·04) g/10 g higher total, lean and fatty consumption per d, respectively. Among men, fish consumption was not statistically significantly associated with weight change. Adjustment for potential over- or underestimation of fish consumption did not systematically change the observed associations, but the 95 % CI became wider. The results in subgroups from analyses stratified by age or BMI at enrolment were not systematically different. In conclusion, the present study suggests that fish consumption has no appreciable association with body-weight gain.
Studies have suggested that moderate alcohol consumption is associated with a reduced risk of CVD and premature mortality in individuals with diabetes mellitus. However, history of alcohol consumption has hardly been taken into account. We investigated the association between current alcohol consumption and mortality in men and women with diabetes mellitus accounting for past alcohol consumption. Within the European Prospective Investigation into Cancer and Nutrition (EPIC), a cohort was defined of 4797 participants with a confirmed diagnosis of diabetes mellitus. Men and women were assigned to categories of baseline and past alcohol consumption. Hazard ratios (HR) and 95 % CI for total mortality were estimated with multivariable Cox regression models, using light alcohol consumption (>0–6 g/d) as the reference category. Compared with light alcohol consumption, no relationship was observed between consumption of 6 g/d or more and total mortality. HR for >6–12 g/d was 0·89 (95 % CI 0·61, 1·30) in men and 0·86 (95 % CI 0·46, 1·60) in women. Adjustment for past alcohol consumption did not change the estimates substantially. In individuals who at baseline reported abstaining from alcohol, mortality rates were increased relative to light consumers: HR was 1·52 (95 % CI 0·99, 2·35) in men and 1·81 (95 % CI 1·04, 3·17) in women. The present study in diabetic individuals showed no association between current alcohol consumption >6 g/d and mortality risk compared with light consumption. The increased mortality risk among non-consumers appeared to be affected by their past alcohol consumption rather than their current abstinence.
We present a study of polygons forming on the free surface of a water flow confined to a stationary cylinder and driven by a rotating bottom plate as described by Jansson et al. (Phys. Rev. Lett., vol. 96, 2006, 174502). In particular, we study the case of a triangular structure, either completely ‘wet’ or with a ‘dry’ centre. For the dry structures, we present measurements of the surface shapes and the process of formation. We show experimental evidence that the formation can take place as a two-stage process: first the system approaches an almost stable rotationally symmetric state and from there the symmetry breaking proceeds like a low-dimensional linear instability. We show that the circular state and the unstable manifold connecting it with the polygon solution are universal in the sense that very different initial conditions lead to the same circular state and unstable manifold. For a wet triangle, we measure the surface flows by particle image velocimetry (PIV) and show that there are three vortices present, but that the strength of these vortices is far too weak to account for the rotation velocity of the polygon. We show that partial blocking of the surface flow destroys the polygons and re-establishes the rotational symmetry. For the rotationally symmetric state our theoretical analysis of the surface flow shows that it consists of two distinct regions: an inner, rigidly rotating centre and an outer annulus, where the surface flow is that of a point vortex with a weak secondary flow. This prediction is consistent with the experimentally determined surface flow.
Electronic properties of thin epitaxial silicon films deposited at temperatures below 650°C by means of ion-assisted deposition strongly depend on substrate orientation as well as on deposition temperature: In (100)-oriented epitaxial films we find a low density of structural defects, and the minority carrier diffusion length is only limited by the presence of point defects or point defect complexes. These investigations also show an improvement of the electronic quality with increasing deposition temperature. Epitaxy on non-(100)-oriented substrates results in a significantly higher density of structural defects. The electronic properties of films deposited on stable flat surfaces, such as (111)- and (113)-oriented substrates are inferior as compared to (100)-oriented films, but are still superior to those of films deposited on faceted surfaces, as shown by light beam induced current and electron back-scattering diffraction measurements of polycrystalline thin films.
Ion-assisted deposition (IAD) enables low temperature (≥ 435°C), high-rate (≤ 0.5 μm/min) epitaxial growth of silicon films. Therefore, IAD is an interesting deposition technique for microelectronic devices and thin film solar cells. The Hall-mobility of monocrystalline epitaxial layers increases with deposition temperature Tdep and reaches values comparable to those of bulk Si at Tdep ≥ 540°C. Polycrystalline epitaxial layers exhibit inhomogeneous electrical properties, as shown by Light Beam Induced Current measurements. Recombination within the grains dominates over recombination at grain boundaries. Secco etching identifies an inhomogeneous density of extended structural defects in the polycrystalline epitaxial layers and in the substrate. A major part of the extended defects in the epitaxial layers originates from defects in the substrate.
We crystallize amorphous silicon (a-Si) layers (thicknesses: ∼300nm and ∼1300nm for comparison) that are deposited on glass substrates (Corning 7059) by low pressure chemical vapor deposition using a continuous wave Ar+-laser. We scan the raw beam with a diameter of ∼60νm in single traces and traces with varying overlap (30-60%). With optimized process parameters (fluence, scan velocity, overlap) we achieve polycrystalline Si with grains as wide as 100νm. The grain boundary population is dominated by first and second order twin boundaries as analyzed by electron backscattering analysis in the scanning electron microscope and convergent beam electron diffraction in the transmission electron microscope. These twins are known not (or only marginally) to degrade the electrical properties of the material. In addition to twins, dislocations and twin lamellae occur at varying densities (depending on grain orientation and process parameters). The recombination activity of the defects is analyzed by EBIC and according to these measurements crystallization receipts are defined that yield the reduction of electrically detrimental defects.
We investigate the crystalline and electrical quality of thin layers epitaxially grown on polycrystalline substrates from metallic solution by the method of electron beam induced current, transmission electron microscopy and etching experiments. We observe a reduced recombination strength of dislocations and small angle grain boundaries, i.e. an improved electrical quality of the epitaxial layer compared to the substrate. The improved quality can be attributed (i) to an altered structure of grain boundaries and dislocations and (ii) to a reduced defect density in the epitaxial layer.
Various techniques of laser glazing are presented. Rules are given for the choise of systems which are suitable for producing amorphous surface layers. Methods of demonstrating the existence of a truly amorphous layer are discussed. Two examples are given: I) electron beam glazing of Ni-Nb coated single crystals 2) laser beam glazing of Fe-B coated Fe-Cr-C cold working steel.
Rapidly quenched tapes of Fe-C-X alloys (X=Cr, Mn,Ni, Co, Al, Si) were produced by melt spinning. The hardness, ductility, grain size and micro and lattice structure were determined. The system Fe 2.1C 13 Cr was chosen for further study. The transformation (isothermal and continious) characteristics were determined for the as quenched and reaustinitized states. The results can be presented in the form of TTT diagrams and hardness measurements