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Brain imaging studies have shown altered amygdala activity during emotion processing in children and adolescents with oppositional defiant disorder (ODD) and conduct disorder (CD) compared to typically developing children and adolescents (TD). Here we aimed to assess whether aggression-related subtypes (reactive and proactive aggression) and callous-unemotional (CU) traits predicted variation in amygdala activity and skin conductance (SC) response during emotion processing.
We included 177 participants (n = 108 cases with disruptive behaviour and/or ODD/CD and n = 69 TD), aged 8–18 years, across nine sites in Europe, as part of the EU Aggressotype and MATRICS projects. All participants performed an emotional face-matching functional magnetic resonance imaging task.
Differences between cases and TD in affective processing, as well as specificity of activation patterns for aggression subtypes and CU traits, were assessed. Simultaneous SC recordings were acquired in a subsample (n = 63). Cases compared to TDs showed higher amygdala activity in response to negative faces (fearful and angry) v. shapes. Subtyping cases according to aggression-related subtypes did not significantly influence on amygdala activity; while stratification based on CU traits was more sensitive and revealed decreased amygdala activity in the high CU group. SC responses were significantly lower in cases and negatively correlated with CU traits, reactive and proactive aggression.
Our results showed differences in amygdala activity and SC responses to emotional faces between cases with ODD/CD and TD, while CU traits moderate both central (amygdala) and peripheral (SC) responses. Our insights regarding subtypes and trait-specific aggression could be used for improved diagnostics and personalized treatment.
To examine treatment, comorbidity status and diagnosis among the French sample of the Caregiver Perspective of Pediatric ADHD (CAPPA) survey.
Carers in 10 EU countries, including France, completed an Internet survey regarding ADHD diagnosis, treatment and comorbidities. Descriptive statistics were calculated for categorical [n (%)] and continuous variables [mean, standard deviation (SD), median, range].
EU carers representing 3688 children/adolescents (6–17 years) with ADHD completed the survey; 486 were from France (median age 10 years, 84% male). Most (77%) French children/adolescents were currently receiving pharmacological treatment(s): 74% stimulant, 15% non-stimulant and 22% antipsychotic. Across countries, stimulant use ranged from 60% (Italy) to 93% (Germany/Netherlands), non-stimulant use from 1% (Germany) to 18% (Sweden) and antipsychotic use from 8% (Germany) to 46% (Italy). Many French children/adolescents received behaviour therapy (BT) after ADHD diagnosis (59%). Among those receiving BT, 52% began prior to starting medication. BT was often discontinued within 6 months (44%) or 6–12 (30%) months. 52% of carers reported ≥ 1 comorbidity; they reported the highest rates of conduct (24%), sleep (11%), eating (6%) and motor-coordination (6%) disorders, and the second-highest rates of anxiety (22%), learning difficulties (15%), oppositional defiant disorder (5%), bipolar disorder (4%) and epilepsy (2%). Time to diagnosis from first doctor's visit averaged 7 months (SD 11, median 3). 81% received a specialist referral. French carers reported the highest perceived difficulty (‘great deal’/’a lot’ of difficulty) obtaining a diagnosis (43%) and a specialist referral (53%).
This sample of French children/adolescents with ADHD had higher non-stimulant and antipsychotic use than most other countries and higher reports of certain comorbid conditions. Carers perceived greater difficulty in obtaining a diagnosis and seeing a specialist, although time to diagnosis was lower compared with a number of other countries.
The elevated level of homocysteine (Hcys) has been observed in patients with schizophrenia. It is proposed that Hcys may act as an oxidant in the model system in vitro and in vivo, the aim of our study was to explain the effect of the elevated Hcys on the selected parameters of oxidative stress, namely thiobarbituric acid reactive substances (TBARS), an index of lipid peroxidation in plasma, the level of carbonyl groups in plasma proteins, as well as the amount of 3-nitrotyrosine in plasma proteins isolated from schizophrenic patients (acc. to DSM-IV criteria). Patients were treated with atypical antipsychotics and interviewed with questionnaire (treatment, diet, addictive substances, metabolic syndrome). High-performance liquid chromatography (HPLC) was used to analyse the total level of homocysteine in plasma. Levels of carbonyl groups and 3-nitrotyrosine residues in plasma proteins were measured by ELISA and a competition ELISA, respectively. The lipid peroxidation in plasma was measured by levels of TBARS. Our results showed that in schizophrenic patients the amount of homocysteine in plasma was higher in comparison with the control (p < 0.00001). We also observed a statistically increased level of biomarkers of oxidative/nitrative stress such as carbonyl groups or 3-nitrotyrosine in plasma proteins from schizophrenic patients. Moreover, our experiments indicate that the correlation between the increased amount of homocysteine and the oxidative stress exists: for carbonyl group and 3-nitrotyrosine R = 0.83, R = 0.84 respectively). Considering the data of our study, we suggest that the elevated Hcys in schizophrenic patients may stimulate the oxidative stress.
The dissolution of a single droplet, containing a mixture of oils, in water is experimentally studied. The oils in the droplet varied in terms of their solubility in water and their hydrophobicity. We demonstrate that the polarity of the droplet constituents strongly influences the dissolution dynamics. A binary-component droplet, containing two polar components (one soluble the other insoluble) exhibits a retarded dissolution as compared to a droplet containing only the soluble component. We argue that in this case the mixture in the droplet can be assumed homogeneous, leading to a smaller effective contact area of the soluble liquid in the droplet with the bulk water, and thus delayed dissolution. On the other hand, it is shown that this is not the case when a polar, soluble component is mixed with an insoluble non-polar component, in which case segregation between the different liquids inside the droplet occurs, leading to Marangoni flows and superspreading of the droplet. The segregation is confirmed by volumetric measurements and by the use of a solvatochromic dye in combination with confocal microscopy, which clearly showed that during dissolution local concentration differences inside the droplet developed.
The Dark Energy Survey is undertaking an observational programme imaging 1/4 of the southern hemisphere sky with unprecedented photometric accuracy. In the process of observing millions of faint stars and galaxies to constrain the parameters of the dark energy equation of state, the Dark Energy Survey will obtain pre-discovery images of the regions surrounding an estimated 100 gamma-ray bursts over 5 yr. Once gamma-ray bursts are detected by, e.g., the Swift satellite, the DES data will be extremely useful for follow-up observations by the transient astronomy community. We describe a recently-commissioned suite of software that listens continuously for automated notices of gamma-ray burst activity, collates information from archival DES data, and disseminates relevant data products back to the community in near-real-time. Of particular importance are the opportunities that non-public DES data provide for relative photometry of the optical counterparts of gamma-ray bursts, as well as for identifying key characteristics (e.g., photometric redshifts) of potential gamma-ray burst host galaxies. We provide the functional details of the DESAlert software, and its data products, and we show sample results from the application of DESAlert to numerous previously detected gamma-ray bursts, including the possible identification of several heretofore unknown gamma-ray burst hosts.
The dissolution process of small (initial (equivalent) radius
mm) long-chain alcohol (of various types) sessile droplets in water is studied, disentangling diffusive and convective contributions. The latter can arise for high solubilities of the alcohol, as the density of the alcohol–water mixture is then considerably less than that of pure water, giving rise to buoyancy-driven convection. The convective flow around the droplets is measured, using micro-particle image velocimetry (
PIV) and the schlieren technique. When non-dimensionalizing the system, we find a universal
scaling relation for all alcohols (of different solubilities) and all droplets in the convective regime. Here
is the Sherwood number (dimensionless mass flux) and
is the Rayleigh number (dimensionless density difference between clean and alcohol-saturated water). This scaling implies the scaling relation
of the convective dissolution time
, which is found to agree with experimental data. We show that in the convective regime the plume Reynolds number (the dimensionless velocity) of the detaching alcohol-saturated plume follows
, which is confirmed by the
PIV data. Here,
is the Schmidt number. The convective regime exists when
is the transition
number as extracted from the data. For
and smaller, convective transport is progressively overtaken by diffusion and the above scaling relations break down.
Weak lensing detections and measurements of filaments have been elusive for a long time. The reason is that the low density contrast of filaments generally pushes the weak lensing signal to unobservably low scales. To nevertheless map the dark matter in filaments exquisite data and unusual systems are necessary. SuprimeCam observations of the supercluster system Abell 222/223 provided the required combination of excellent seeing images and a fortuitous alignment of the filament with the line-of-sight. This boosted the lensing signal to a detectable level and led to the first weak lensing mass measurement of a large-scale structure filament. The filament connecting Abell 222 and Abell 223 is now the only one traced by the galaxy distribution, dark matter, and X-ray emission from the hottest phase of the warm-hot intergalactic medium. The combination of these data allows us to put the first constraints on the hot gas fraction in filaments.
Data on the internal velocity distribution of flowing sediment–fluid mixtures such as debris flows are rare, but necessary for model development and testing. A probe to measure the mean particle velocity at different depths and different locations within experimental debris flows in a 4 m diameter rotating drum was developed. In addition, the flow depth, basal normal stress and basal pore fluid pressure were also measured. Results show that for a given sediment–fluid mixture the velocity profiles collapse to distinct non-dimensional profiles. Macroscopic flow behaviour shows great similarity, with mean surface slopes weakly dependent on the shear rate for water-saturated gravel, but strongly shear-rate-dependent when pores are filled with mud. Poorly sorted material with a high content of fines produced fluid pressures close to normal stress and sidewall friction had a strong effect on the flow pattern. Our results reveal variability in profile characteristics for flows displaying similar macro-dynamics and provide data for model testing.
While the self-learning kinetic Monte Carlo (SLKMC) method enables the calculation of transition rates from a realistic potential, implementations of it were usually limited to one specific surface orientation. An example is the fcc (111) surface in Latz et al. 2012, J. Phys.: Condens. Matter 24, 485005. This work provides an extension by means of detecting the local orientation, and thus allows for the accurate simulation of arbitrarily shaped surfaces. We applied the model to the diffusion of Ag monolayer islands and voids on a Ag(111) and Ag(001) surface, as well as the relaxation of a three-dimensional spherical particle.
Understanding electromigration effects in monocrystalline metal becomes of increasing interest with decreasing width and thickness of interconnects. Using a three-dimensional, atomistic model based on the Kinetic Monte Carlo method, we investigate voids in monocrystalline silver. Subject to electromigration, voids begin to drift. We show that the drift velocity not only depends on the void size, but also on the electromigration force direction, with respect to the crystallographic orientation.
This study examined whether children's coping strategies are related to post-concussive symptoms following mild traumatic brain injury (TBI) versus orthopedic injury (OI). Participants were 8- to 15-year-old children with mild TBI (n = 167) or OI (n = 84). They rated their current preferred coping strategies and post-injury symptoms at 2 weeks (baseline) and 1, 3, and 12 months post-injury. Children's reported use of coping strategies did not vary significantly over time, so their baseline coping ratings were examined as predictors of post-concussive symptoms across time. Self-ratings of symptoms were positively related to emotion-focused strategies and negatively related to problem-focused engagement after both mild TBI and OI. Higher problem-focused disengagement predicted larger group differences in children's ratings of symptoms, suggesting that problem-focused disengagement moderates the effects of mild TBI. Coping strategies collectively accounted for approximately 10–15% of the variance in children's post-concussive symptoms over time. The findings suggest that coping may play an important role in accounting for children's perceptions of post-concussive symptoms after mild TBI. (JINS, 2011, 17, 317–326)
Using a statistical model for the effects of decoherence , we show that in linear tight-binding samples ohmic conductance (resistance proportional to length) is reached for any finite density p of decoherence sites, if the chemical potential μ of the contacts is within a conducting band. If μ is outside a band, or if due to disorder, no bands form, for high decoherence densities p>p* still ohmic conductance is reached, where p* is a critical decoherence density. For p<p*, the sample resistance increases exponentially with the length.
The occurrence of postconcussive symptoms (PCS) following mild traumatic brain injury (TBI) in children may depend on cognitive reserve capacity. This prospective, longitudinal study examined whether the relationship between mild TBI and PCS is moderated by cognitive ability, which served as a proxy for cognitive reserve. Participants included 182 children with mild TBI and 99 children with orthopedic injuries (OI), ranging from 8 to 15 years of age when injured. Mild TBI were classified as complicated (n = 32) or uncomplicated (n = 150) depending on whether they were associated with trauma-related intracranial abnormalities on magnetic resonance imaging. PCS were assessed initially within 3 weeks of injury, and again at 1, 3, and 12 months post injury. The initial assessment also included standardized tests of children’s cognitive skills and retrospective parent ratings of pre-injury symptoms. Hierarchical linear modeling indicated that ratings of PCS were moderated jointly by cognitive ability and injury severity. Children of lower cognitive ability with a complicated mild TBI were especially prone to cognitive symptoms across time according to parents and to high acute levels of PCS according to children’s self-ratings. Cognitive reserve is an important moderator of the outcomes of mild TBI in children and adolescents. (JINS, 2010, 16, 94–105.)
Jets arising from rivers, streams and tidal flows entering still waters differ
from most experimental studies of jets both in aspect ratio and in the presence
of a solid bottom boundary and an upper free surface. Despite these differences,
the applicability of experimental jet studies to these systems remains largely
untested by either field or realistically scaled experimental studies. Here we
present experimental results for a wall-bounded plane jet scaled to jets created
by flow discharging into floodplain lakes. A characteristic feature of both our
prototype and experimental jets is the presence of large-scale meandering
turbulent structures that span the width of the jets. In our experimental jets,
we observe self-similarity in the distribution of mean streamwise velocities by
a distance of six channel widths downstream of the jet outlet. After a distance
of nine channel widths the velocity decay and the spreading rates largely agree
with prior experimental results for plane jets. The magnitudes and distributions
of the cross-stream velocity and lateral shear stresses approach self-preserving
conditions in the upper half of the flow, but decrease in magnitude, and deviate
from self-preserving distributions with proximity to the bed. The presence of
the meandering structure has little influence on the mean structure of the jet,
but dominates the jet turbulence. A comparison of turbulence analysed at time
scales both greater than and less than the period of the meandering structure
indicates that these structures increase turbulence intensities by 3–5
times, and produce lateral shear stresses and momentum diffusivities that are
one and two orders of magnitude greater, respectively, than turbulence generated
by bed friction alone.