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Background: Although attention deficit hyperactivity disorder (ADHD) is considered a valid diagnosis for children with intellectual disability, no studies have evaluated the invariance of ADHD symptom ratings across children with and without intellectual disability. Method: Parents completed ratings on the ADHD symptoms for 189 children with intellectual disability and for 474 children without intellectual disability. Differential item functioning analysis was used to determine the equivalence of the ADHD symptoms across the two groups. Results: The symptoms loses things, talks too much, and blurts out answers showed significant bias against children with intellectual disability. The prevalence of ADHD in children with intellectual disability was 18% (according to the symptom criterion), and 7.4% when the academic and/or social impairment criterion was also considered. Conclusions: Most of the ADHD symptoms can be valid for the assessment of ADHD in children with mild and moderate intellectual disability. ADHD symptoms may be used in further studies to establish base rates of the disorder in the intellectual disability population.

Multiple co-occurring stressors may affect food webs in ways that are not predictable by studying individual stressors. Here the authors apply a network interaction model to a marine food web in the Arctic, finding that nonlinear interactions between stressors can more than double the risk of population collapse compared to simpler simulations.

BackgroundThe Clinical Opiate Withdrawal Scale (COWS) is used to assess withdrawal in clinical trials and practice. The aims of this study were to examine the inter-item correlations and factor structure of the COWS in opioid-dependent men and women.MethodsThis is a secondary data analysis of the National Drug Abuse Treatment Clinical Trials Network 0003, a randomized clinical trial that compared buprenorphine/naloxone tapering strategies. The trial included 11 sites in 10 US cities. Participants were opioid-dependent individuals (n=516) that had data on the COWS. The COWS at study baseline was analyzed in this study.ResultsInter-item correlations showed weak to moderate relationships among the items. A 1-factor model did not fit the data for men (comparative fit index (CFI)=.801, root mean square error of approximation (RMSEA)=.073, weighted root mean square residual (WRMR)=1.132) or women (CFI=.694, RMSEA=.071, WRMR=.933), where resting pulse rate was not related to withdrawal for men, and yawning and gooseflesh skin was not related to withdrawal for women. A reduced model comprised of only the 8 items that were significantly related to the construct of withdrawal in both men and women, and an exploratory 2-factor model, were also assessed but not retained due to inconsistencies across gender.ConclusionsWhen traditional psychometric models are applied to the COWS, it appears that the scale may not relate to a single underlying construct of withdrawal. Further research testing the hypothesized factor structure in other opioid-dependent samples is needed.

Summary: Attention‐deficit/hyperactivity disorder and an evening chronotype are both common among college students, and there is growing interest in understanding the possible link between attention‐deficit/hyperactivity disorder and circadian function. However, mixed findings have been reported, and many of the existing studies have used small samples that were unable to examine chronotype across attention‐deficit/hyperactivity disorder presentations. Participants were 4751 students (73% female; 80% White), aged 18–29 years (M = 19.28, SD = 1.50), from five universities who completed measures assessing attention‐deficit/hyperactivity disorder, depressive and anxiety symptoms, as well as the Morningness–Eveningness Questionnaire to assess chronotype (categorical) and circadian preference (dimensional). Participants with either attention‐deficit/hyperactivity disorder predominantly inattentive presentation or attention‐deficit/hyperactivity disorder combined presentation had higher rates of being an evening type (47.2% and 41.5%, respectively) than participants without elevated attention‐deficit/hyperactivity disorder (28.5%), and participants with attention‐deficit/hyperactivity disorder predominantly inattentive presentation also had higher rates of being an evening type than participants with attention‐deficit/hyperactivity disorder predominantly hyperactive–impulsive presentation (30.7%). Dimensional analyses indicated that attention‐deficit/hyperactivity disorder inattentive symptoms were more strongly associated than hyperactive–impulsive symptoms with eveningness preference. Finally, greater eveningness preference strengthened the association between attention‐deficit/hyperactivity disorder inattention and depressive symptoms but not anxiety symptoms. This is the largest study to document that college students with elevated attention‐deficit/hyperactivity disorder symptoms are more likely to be evening types than other college students, and inattentive symptoms in particular are associated with later circadian preference. [ABSTRACT FROM AUTHOR]

Activation of PDGFRA by genomic aberrations contributes to tumor progression in several tumor types. Here, the authors perform functional characterization of 16 novel PDGFRA mutations identified from different tumor types and demonstrate that a neomorphic PDGFRA extracellular domain driver mutation is resistant to PDGFRA targeted therapies.

In north-western Tibet (34.0° N, 82.2° E) near lake Aru Co, the entire ablation areas of two glaciers (Aru-1 and Aru-2) suddenly collapsed on 17 July and 21 September 2016. The masses transformed into ice avalanches with volumes of 68 and 83×106 m3 and ran out up to 7 km in horizontal distance, killing nine people. The only similar event currently documented is the 130×106 m3 Kolka Glacier rock and ice avalanche of 2002 (Caucasus Mountains). Using climatic reanalysis, remote sensing, and three-dimensional thermo-mechanical modelling, we reconstructed the Aru glaciers' thermal regimes, thicknesses, velocities, basal shear stresses, and ice damage prior to the collapse in detail. Thereby, we highlight the potential of using emergence velocities to constrain basal friction in mountain glacier models. We show that the frictional change leading to the Aru collapses occurred in the temperate areas of the polythermal glaciers and is not related to a rapid thawing of cold-based ice. The two glaciers experienced a similar stress transfer from predominant basal drag towards predominant lateral shearing in the detachment areas and during the 5–6 years before the collapses. A high-friction patch is found under the Aru-2 glacier tongue, but not under the Aru-1 glacier. This difference led to disparate behaviour of both glaciers, making the development of the instability more visible for the Aru-1 glacier through enhanced crevassing and terminus advance over a longer period. In comparison, these signs were observable only over a few days to weeks (crevasses) or were absent (advance) for the Aru-2 glacier. Field investigations reveal that those two glaciers were underlain by soft, highly erodible, and fine-grained sedimentary lithologies. We propose that the specific bedrock lithology played a key role in the two Tibet and the Caucasus Mountains giant glacier collapses documented to date by producing low bed roughness and large amounts of till, rich in clay and silt with a low friction angle. The twin 2016 Aru collapses would thus have been driven by a failing basal substrate linked to increasing pore water pressure in the subglacial drainage system in response to increases in surface melting and rain during the 5–6 years preceding the collapse dates.

Objective Method Results Conclusions The identification of a common set of symptoms for assessing cognitive disengagement syndrome (CDS, formerly sluggish cognitive tempo) for early childhood (ages 5–8), middle childhood (ages 9–12), and adolescence (ages 13–16) is needed to advance research on the developmental psychopathology of CDS (i.e. a common symptom set with comparable internal and external validity for each age group).Parents of a nationally representative sample of 5,525 Spanish children and adolescents (ages 5 to 16, 56.1% boys) completed measures of CDS, attention-deficit/hyperactivity disorder-inattention (ADHD-IN), and other measures.First, the 15 CDS symptoms showed convergent and discriminant validity relative to the ADHD-IN symptoms within each age group. Second, CDS showed stronger first-order and unique associations than ADHD-IN with anxiety, depression, somatization, daytime sleep-related impairment, and nighttime sleep disturbance, whereas ADHD-IN showed stronger first-order and unique associations than CDS with ADHD-hyperactivity/impulsivity, oppositional defiant disorder, and academic impairment. Third, CDS showed stronger first-order and unique associations than ADHD-IN with a history of having an anxiety, depression, or bipolar disorder diagnosis, whereas ADHD-IN showed stronger first-order and unique associations with having an ADHD diagnosis.The identification of a common set of CDS symptoms spanning early childhood to adolescence allows for the advancement of research on CDS, with a particular need now for longitudinal studies and examination of CDS with other functional outcomes and across other cultural contexts. [ABSTRACT FROM AUTHOR]