443 research outputs found

    Non-Destructive Identification of Cold and Extremely Localized Single Molecular Ions

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    A simple and non-destructive method for identification of a single molecular ion sympathetically cooled by a single laser cooled atomic ion in a linear Paul trap is demonstrated. The technique is based on a precise determination of the molecular ion mass through a measurement of the eigenfrequency of a common motional mode of the two ions. The demonstrated mass resolution is sufficiently high that a particular molecular ion species can be distinguished from other equally charged atomic or molecular ions having the same total number of nucleons

    Hungarian International Development Cooperation: Context, Stakeholders and Performance

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    This paper explores the domestic and international context of Hungary's emerging international development policy. Specifically, it looks at three factors that may influence how this policy operates: membership in the European Union (EU) and potential ‘Europeanization’, Hungary's wider foreign policy strategy, and the influence of domestic stakeholders. In order to uncover how these factors affect the country's international development policy, semi-structured interviews were carried out with the main stakeholders. The main conclusions are: (1) While accession to the EU did play a crucial role in restarting Hungary's international development policy, the integration has had little effect since then; (2) international development policy seems to serve mainly Hungary's regional strategic foreign policy and economic interests, and not its global development goals; and (3) although all the domestic development stakeholders are rather weak, the Ministry of Foreign Affairs (MFA) still seems to play a dominating role. Convergence with European requirements and best practices is, therefore, clearly hindered by foreign policy interests and also by the weakness of non- governmental stakeholders

    Lifetime measurement of the metastable 3d 2D5/2 state in the 40Ca+ ion using the shelving technique on a few-ion string

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    We present a measurement of the lifetime of the metastable 3d 2D5/2 state in the 40Ca+ ion, using the so-called shelving technique on a string of five Doppler laser-cooled ions in a linear Paul trap. A detailed account of the data analysis is given, and systematic effects due to unwanted excitation processes and collisions with background gas atoms are discussed and estimated. From a total of 6805 shelving events, we obtain a lifetime tau=1149+/-14(stat.)+/-4(sys.)ms, a result which is in agreement with the most recent measurements.Comment: 10 pages, 7 figures. Submitted for publicatio

    Changes in the Frontotemporal Cortex and Cognitive Correlates in First-Episode Psychosis

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    Background: Loss of cortical volume in frontotemporal regions has been reported in patients with schizophrenia and their relatives. Cortical area and thickness are determined by different genetic processes, and measuring these parameters separately may clarify disturbances in corticogenesis relevant to schizophrenia. Our study also explored clinical and cognitive correlates of these parameters.Methods: Thirty-seven patients with first-episode psychosis (34 schizophrenia, 3 schizoaffective disorder) and 38 healthy control subjects matched for age and sex took part in the study. Imaging was performed on an magnetic resonance imaging 1.5-T scanner. Area and thickness of the frontotemporal cortex were measured using a surface-based morphometry method (Freesurfer). All subjects underwent neuropsychologic testing that included measures of premorbid and current IQ, working and verbal memory, and executive function.Results: Reductions in cortical area, more marked in the temporal cortex, were present in patients. Overall frontotemporal cortical thickness did not differ between groups, although regional thinning of the right superior temporal region was observed in patients. There was a significant association of both premorbid IQ and IQ at disease onset with area, but not thickness, of the frontotemporal cortex, and working memory span was associated with area of the frontal cortex. These associations remained significant when only patients with schizophrenia were considered.Conclusions: Our results suggest an early disruption of corticogenesis in schizophrenia, although the effect of subsequent environmental factors cannot be excluded. In addition, cortical abnormalities are subject to regional variations and differ from those present in neurodegenerative diseases

    Motor coordination, working memory, and academic achievement in a normative adolescent sample: Testing a mediation model

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    The aim of the present study was to examine whether the relationship between motor coordination and academic achievement is mediated by working memory (WM) in a normative adolescent sample. Participants included 93 adolescents aged 12–16. The Movement Assessment Battery for Children-2 provided three indicators of motor coordination (Manual Dexterity, Aiming and Catching, and Balance), the WM Index of the Wechsler Intelligence Scale for Children-IV and the N-back paradigm provided two indicators of WM, and the Wechsler Individual Achievement Test-II provided three indicators of academic achievement (Word Reading, Spelling, and Numerical Operations). Structural equation modeling, controlling for verbal comprehension, attention deficit hyperactivity disorder symptoms, and socioeconomic status, suggested that the association between motor coordination and academic achievement may be best understood in terms of a mechanism whereby motor coordination (specifically, Aiming and Catching skills) has an indirect impact on academic outcomes via WM. These findings have important implications for the assessment and treatment of motor coordination and learning difficulties as well as in increasing the understanding of the possible neural mechanisms underpinning the relationship between these areas

    Molar pregnancy and childhood cancer: a population-based linkage study from Denmark

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    We observed a relative risk of 1.40 (95% confidence interval; 0.86–2.16) for cancers diagnosed under the age 20 in 6192 offspring of 3431 mothers with a molar pregnancy, indicating it is not a major determinant of childhood cancer

    Atomoxetine for the treatment of Attention-Deficit/Hyperactivity Disorder (ADHD) in children with ADHD and dyslexia

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    <p>Abstract</p> <p>Background</p> <p>The objective of this study was to assess the effects of atomoxetine on treating attention-deficit/hyperactivity disorder (ADHD), on reading performance, and on neurocognitive function in youth with ADHD and dyslexia (ADHD+D).</p> <p>Methods</p> <p>Patients with ADHD (n = 20) or ADHD+D (n = 36), aged 10-16 years, received open-label atomoxetine for 16 weeks. Data from the ADHD Rating Scale-IV (ADHDRS-IV), Kaufman Test of Educational Achievement (K-TEA), Working Memory Test Battery for Children (WMTB-C), and Life Participation Scale for ADHD-Child Version (LPS-C) were assessed.</p> <p>Results</p> <p>Atomoxetine demonstrated significant improvement for both groups on the ADHDRS-IV, LPS-C, and K-TEA reading comprehension standard and composite scores. K-TEA spelling subtest improvement was significant for the ADHD group, whereas the ADHD+D group showed significant reading decoding improvements. Substantial K-TEA reading and spelling subtest age equivalence gains (in months) were achieved for both groups. The WMTB-C central executive score change was significantly greater for the ADHD group. Conversely, the ADHD+D group showed significant phonological loop score enhancement by visit over the ADHD group. Atomoxetine was well tolerated, and commonly reported adverse events were similar to those previously reported.</p> <p>Conclusions</p> <p>Atomoxetine reduced ADHD symptoms and improved reading scores in both groups. Conversely, different patterns and magnitude of improvement in working memory component scores existed between ADHD and ADHD+D patients. Though limited by small sample size, group differences in relation to the comparable changes in improvement in ADHD symptoms could suggest that brain systems related to the therapeutic benefit of atomoxetine in reducing ADHD symptoms may be different in individuals with ADHD+D and ADHD without dyslexia.</p> <p>Trial Registration</p> <p>Clinical Trial Registry: ClinicalTrials.gov: NCT00191048</p

    A trait-based approach reveals the feeding selectivity of a small endangered Mediterranean fish

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    Functional traits are growing in popularity in modern ecology, but feeding studies remain primarily rooted in a taxonomic-based perspective. However, consumers do not have any reason to select their prey using a taxonomic criterion, and prey assemblages are variable in space and time, which makes taxon-based studies assemblage-specific. To illustrate the benefits of the trait-based approach to assessing food choice, we studied the feeding ecology of the endangered freshwater fish Barbus meridionalis. We hypothesized that B. meridionalis is a selective predator which food choice depends on several prey morphological and behavioral traits, and thus, its top-down pressure may lead to changes in the functional composition of in-stream macroinvertebrate communities. Feeding selectivity was inferred by comparing taxonomic and functional composition (13 traits) between ingested and free-living potential prey using the Jacob's electivity index. Our results showed that the fish diet was influenced by 10 of the 13 traits tested. Barbus meridionalis preferred prey with a potential size of 5–10 mm, with a medium–high drift tendency, and that drift during daylight. Potential prey with no body flexibility, conical shape, concealment traits (presence of nets and/or cases, or patterned coloration), and high aggregation tendency had a low predation risk. Similarly, surface swimmers and interstitial taxa were low vulnerable to predation. Feeding selectivity altered the functional composition of the macroinvertebrate communities. Fish absence favored taxa with weak aggregation tendency, weak flexibility, and a relatively large size (10–20 mm of potential size). Besides, predatory invertebrates may increase in fish absence. In conclusion, our study shows that the incorporation of the trait-based approach in diet studies is a promising avenue to improve our mechanistic understanding of predator–prey interactions and to help predict the ecological outcomes of predator invasions and extinctions

    How Distinctive are ADHD and RD? Results of a Double Dissociation Study

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    The nature of the comorbidity between Attention-Deficit/Hyperactivity Disorder (ADHD) and Reading Disability (RD) was examined using a double dissociation design. Children were between 8 and 12 years of age and entered into four groups: ADHD only (n = 24), ADHD+RD (n = 29), RD only (n = 41) and normal controls (n = 26). In total, 120 children participated in the study; 38 girls and 82 boys. Both ADHD and RD were associated with impairments in inhibition and lexical decision, although inhibition and lexical decision were more severely impaired in RD than in ADHD. Visuospatial working memory deficits were specific to children with only ADHD. It is concluded that there was overlap on lexical decision and to a lesser extent on inhibition between ADHD and RD. In ADHD, impairments were dependent on IQ, which suggest that the overlap in lexical decision and inhibition is different in origin for ADHD and RD. The ADHD only group was specifically characterized by deficits in visuospatial working memory. Hence, no double dissociation between ADHD and RD was found on executive functioning and lexical decision

    Global and Regional Differences in Brain Anatomy of Young Children Born Small for Gestational Age

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    In children who are born small for gestational age (SGA), an adverse intrauterine environment has led to underdevelopment of both the body and the brain. The delay in body growth is (partially) restored during the first two years in a majority of these children. In addition to a negative influence on these physical parameters, decreased levels of intelligence and cognitive impairments have been described in children born SGA. In this study, we used magnetic resonance imaging to examine brain anatomy in 4- to 7-year-old SGA children with and without complete bodily catch-up growth and compared them to healthy children born appropriate for gestational age. Our findings demonstrate that these children strongly differ on brain organisation when compared with healthy controls relating to both global and regional anatomical differences. Children born SGA displayed reduced cerebral and cerebellar grey and white matter volumes, smaller volumes of subcortical structures and reduced cortical surface area. Regional differences in prefrontal cortical thickness suggest a different development of the cerebral cortex. SGA children with bodily catch-up growth constitute an intermediate between those children without catch-up growth and healthy controls. Therefore, bodily catch-up growth in children born SGA does not implicate full catch-up growth of the brain
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