Comorbid depressive disorders in ADHD. the role of ADHD severity, subtypes and familial psychiatric disorders

ObjectiveaaTo evaluate the presence of Major Depressive Disorder (MDD) and Dysthymic Disorder (DD) in a sample of Italian children with Attention Deficit Hyperactivity Disorder (ADHD) and to explore specific features of comorbid depressive disorders in ADHD. MethodsaaThree hundred and sixty-six consecutive, drug-naïve Caucasian Italian outpatients with ADHD were recruited and comorbid disorders were evaluated using DSM-IV-TR criteria. To evaluate ADHD severity, parents of all children filled out the ADHD Rating Scale. Thirty-seven children with comorbid MDD or DD were compared with 118 children with comorbid conduct disorder and 122 without comorbidity for age, sex, IQ level, family psychiatric history, and ADHD subtypes and severity. Resultsaa42 of the ADHD children displayed comorbid depressive disorders: 16 exhibited MDD, 21 DD, and 5 both MDD and DD. The frequency of hyperactive-impulsive subtypes was significantly lower in ADHD children with depressive disorders, than in those without any comorbidity. ADHD children with depressive disorders showed a higher number of familial psychiatric disorders and higher score in the Inattentive scale of the ADHD Rating Scale, than children without any comorbidity. No differences were found for age, sex and IQ level between the three groups. Conclusions: Consistent with previous studies in other countries, depressive disorders affect a significant proportion of ADHD children in Italy. Patient assessment and subsequent treatment should take into consideration the possible presence of this comorbidity, which could specifically increase the severity of ADHD attention problems

Combinatorial and topological aspects of path posets, and multipath cohomology

Multipath cohomology is a cohomology theory for directed graphs, which is defined using the path poset. The aim of this paper is to investigate combinatorial properties of path posets and to provide computational tools for multipath cohomology. In particular, we develop acyclicity criteria and provide computations of multipath cohomology groups of oriented linear graphs. We further interpret the path poset as the face poset of a simplicial complex, and we investigate realisability problems

Can alexithymia be assessed through an interview in adolescents? The Toronto Structured Interview for Alexithymia: Reliability, concurrent validity, discriminant validity, and relationships with emotional-behavioral symptoms

Alexithymia is connected to adolescents' psychopathology, but the current methods of assessment present limitations. The Toronto Structured Interview for Alexithymia (TSIA) was developed to overcome the limits of the main used self-rating scale in adults, but no studies investigated its feasibility with adolescents. This study involved 95 community adolescents aged 12-19 years. Adolescents were assessed with the TSIA, the 20-item Toronto Alexithymia Scale (TAS-20), the Verbal Comprehension Index of the WISC-IV for verbal skills, and the Child Behavior Checklist and Youth Self Report for emotional-behavioral symptoms. The aims were to investigate the TSIA internal consistency, concurrent validity with the TAS-20, discriminant validity with participants' verbal skills, and relationships with emotional-behavioral symptoms. TSIA showed good internal consistency, concurrent validity with the TAS-20 (except for factor DDF), and independence by participants' verbal skills, but few relationships with emotional-behavioral symptoms. In conclusion, TSIA showed some good psychometric proprieties but little convergence with research findings obtained with the TAS-20, suggesting the need for further research to check the feasibility of using the TSIA with adolescents. Meanwhile, a precautionary multi-method assessment of alexithymia is recommended

The ominous fate of exomoons around hot Jupiters in the high-eccentricity migration scenario

All the giant planets in the Solar system host a large number of natural satellites. Moons in extrasolar systems are difficult to detect, but a Neptune-sized exomoon candidate has been recently found around a Jupiter-sized planet in the Kepler-1625b system. Due to their relative ease of detection, hot Jupiters (HJs), which reside in close orbits around their host stars with a period of a few days, may be very good candidates to search for exomoons. It is still unknown whether the HJ population can host (or may have hosted) exomoons. One suggested formation channel for HJs is high-eccentricity migration induced by a stellar binary companion combined with tidal dissipation. Here, we investigate under which circumstances an exomoon can prevent or allow high-eccentricity migration of a HJ, and in the latter case, if the exomoon can survive the migration process. We use both semi-analytic arguments, as well as direct N-body simulations including tidal interactions. Our results show that massive exomoons are efficient at preventing high-eccentricity migration. If an exomoon does instead allow for planetary migration, it is unlikely that the HJ formed can host exomoons since the moon will either spiral on to the planet or escape from it during the migration process. A few escaped exomoons can become stable planets after the Jupiter has migrated, or by tidally migrating themselves. The majority of the exomoons end up being ejected from the system or colliding with the primary star and the host planet. Such collisions might none the less leave observable features, such as a debris disc around the primary star or exorings around the close-in giant

Learning Early Exit Strategies for Additive Ranking Ensembles

Modern search engine ranking pipelines are commonly based on large machine-learned ensembles of regression trees. We propose LEAR, a novel - learned - technique aimed to reduce the average number of trees traversed by documents to accumulate the scores, thus reducing the overall query response time. LEAR exploits a classifier that predicts whether a document can early exit the ensemble because it is unlikely to be ranked among the final top-k results. The early exit decision occurs at a sentinel point, i.e., after having evaluated a limited number of trees, and the partial scores are exploited to filter out non-promising documents. We evaluate LEAR by deploying it in a production-like setting, adopting a state-of-the-art algorithm for ensembles traversal. We provide a comprehensive experimental evaluation on two public datasets. The experiments show that LEAR has a significant impact on the efficiency of the query processing without hindering its ranking quality. In detail, on a first dataset, LEAR is able to achieve a speedup of 3x without any loss in NDCG@10, while on a second dataset the speedup is larger than 5x with a negligible NDCG@10 loss (< 0.05%)

Poverty and Disability: A critical review of the literature in low and middle-income countries

While it is widely assumed that disability, poverty and health are closely linked, this is the first critical review on the subject that explicitly asks: ‘What is the current evidence base for the link between poverty, disability and health in low- and middle-income countries? The methods used have been adapted from the EPPI Centre (EPPI-Centre, 2007) and the work of Greenhalgh (Greenhalgh, Robert, Macfarlane, Bate, Kyriakidou, & Peacock, 2005) A total of 964 papers were identified and, of these, 293 were selected for further review based on appropriateness of fit. An initial review of the 293 papers, paying particular attention to those papers that presented an evidence base, found only 27 papers (9.2% of total papers reviewed) met the established inclusion criteria for a critical review. Widening these inclusion criteria did not produce significantly more evidence based papers for review. Thus, the most significant finding from this study is the current lack of strong evidence on the links between disability, poverty and health in LMICs upon which to build global policy and programming. Within the group of papers available for review, we identify a small but growing evidence base that indicates that there are substantial links between disability, poverty and health; however emerging research indicates that these links are more complex and nuanced than is currently assumed. We conclude with a call for more attention to building an evidence base on the interactions between disability, poverty and health. The absence of a robust evidence base that explicitly links these issues, in conjunction with the lack of appropriate benchmarks and indicators to measure disability rights commitments (including poverty reduction), will otherwise result in a “democratic deficit”

Quaternary structure change as a mechanism for the regulation of thymidine kinase 1-like enzymes

SummaryThe human cytosolic thymidine kinase (TK) and structurally related TKs in prokaryotes play a crucial role in the synthesis and regulation of the cellular thymidine triphosphate pool. We report the crystal structures of the TK homotetramer from Thermotoga maritima in four different states: its apo-form, a binary complex with thymidine, as well as the ternary structures with the two substrates (thymidine/AppNHp) and the reaction products (TMP/ADP). In combination with fluorescence spectroscopy and mutagenesis experiments, our results demonstrate that ATP binding is linked to a substantial reorganization of the enzyme quaternary structure, leading to a transition from a closed, inactive conformation to an open, catalytic state. We hypothesize that these structural changes are relevant to enzyme function in situ as part of the catalytic cycle and serve an important role in regulating enzyme activity by amplifying the effects of feedback inhibitor binding

Engineering Silicon Nanocrystals: Theoretical study of the effect of Codoping with Boron and Phosphorus

We show that the optical and electronic properties of nanocrystalline silicon can be efficiently tuned using impurity doping. In particular, we give evidence, by means of ab-initio calculations, that by properly controlling the doping with either one or two atomic species, a significant modification of both the absorption and the emission of light can be achieved. We have considered impurities, either boron or phosphorous (doping) or both (codoping), located at different substitutional sites of silicon nanocrystals with size ranging from 1.1 nm to 1.8 nm in diameter. We have found that the codoped nanocrystals have the lowest impurity formation energies when the two impurities occupy nearest neighbor sites near the surface. In addition, such systems present band-edge states localized on the impurities giving rise to a red-shift of the absorption thresholds with respect to that of undoped nanocrystals. Our detailed theoretical analysis shows that the creation of an electron-hole pair due to light absorption determines a geometry distortion that in turn results in a Stokes shift between adsorption and emission spectra. In order to give a deeper insight in this effect, in one case we have calculated the absorption and emission spectra going beyond the single-particle approach showing the important role played by many-body effects. The entire set of results we have collected in this work give a strong indication that with the doping it is possible to tune the optical properties of silicon nanocrystals.Comment: 14 pages 19 figure