Stability of homogeneous bundles on P^3

We study the stability of some homogeneous bundles on P^3 by using their representations of the quiver associated to the homgeneous bundles on P^3. In particular we show that homogeneous bundles on P^3 whose support of the quiver representation is a parallelepiped are stable, for instance the bundles E whose minimal free resolution is of the kind 0 --> S^{l_1, l_2, l_3} V (t) --> S^{l_1 +s, l_2, l_3} V (t+s) --> E --> 0 are stable.Comment: to appear in Geometriae Dedicata http://www.springer.com/mathematics/geometry/journal/1071

Widespread drying of European peatlands in recent centuries

This is the author accepted manuscript. The final version is available from Nature Research via the DOI in this record Climate warming and human impacts are thought to be causing peatlands to dry,potentially converting them from sinks to sources of carbon. However, it is unclear whether the hydrological status of peatlands has moved beyond their natural envelope. Here we show that European peatlands have undergone substantial, widespread drying during the last ~300 years. We analyse testate amoeba-derived hydrological reconstructions from 31 peatlands across Britain, Ireland, Scandinavia and continental Europe to examine changes in peatland surface wetness during the last 2000 years. 60% of our study sites were drier during the period CE 1800-2000 than they have been for the last 600 years; 40% of sites were drier than they have been for 1000 years; and 24% of sites were drier than they have been for 2000 years. This marked recent transition in the hydrology of European peatlands is concurrent with compound pressures including climatic drying, warming and direct human impacts on peatlands, although these factors vary between regions and individual sites. Our results suggest that the wetness of many European peatlands may now be moving away from natural baselines. Our findings highlight the need for effective management and restoration of European peatlands.Natural Environment Research Council (NERC

One-Year Follow-Up of Guided Self-Help for Parents of Preschool Children With Externalizing Behavior

Self-help programs are an effective intervention for parents of children with externalizing behavior. A number of studies have shown that self-administered parent training has positive short-term effects on a child's behavior, but there is little research done on long-term outcomes. This paper reports results from a 1-year follow-up of a randomized controlled prevention trial of self-administered parent training with minimal therapist contact. In the initial prevention trial, we randomly assigned 48 preschool children with elevated levels of externalizing behavior to either a treatment group (TG) or a waitlist control group (WLC). The intervention consisted of written material and brief weekly telephone consultations. Thirty-six families (25 TG families, 11 WLC families) completed the self-help program. Twenty-five of these participated in a follow-up assessment 1 year after the intervention. There were no significant changes from post-test to follow-up on measures of child behavior (e.g., Attention-Deficit/Hyperactivity Disorder and Oppositional Defiant Disorder symptom rating scales) and parental mental health, indicating that gains achieved post-intervention were maintained for at least 1 year. Moreover, the percentage of children with substantial behavior problems was reduced from pre-intervention to follow-up. These findings provide evidence that telephone-assisted self-help programs can be effective in the prevention of disruptive behavior problems

Does sensitivity to orthographic regularities influence reading and spelling acquisition? A 1-year prospective study

Recent studies focused on the influence of orthographic processing on reading and spelling performance. It was found that orthographic processing is an independent predictor of reading and spelling performance in different languages and children of different ages. This study investigated sensitivity to orthographic regularities in German-speaking children (N = 31) prior and during formal reading and spelling instruction. In addition, the relationship between sensitivity to orthographic regularities and reading and spelling performance was explored. Two aspects of children's sensitivity to orthographic regularities (sensitivity to frequent double consonants and sensitivity to legal positions of double consonants) were measured with a nonword forced choice task. The results show that sensitivity to orthographic regularities improved significantly from kindergarten to first grade. Moreover, children's sensitivity to orthographic regularities at the end of first grade accounted for a significant amount of unique variance in their reading and spelling performance. These results suggest that orthographic sensitivity on a sublexical level is important for the development of reading and spelling skills

Reliability and Validity of Teacher-Rated Symptoms of Oppositional Defiant Disorder and Conduct Disorder in a Clinical Sample

Background/Aims: It is recommended to use information from multiple informants when making diagnostic decisions concerning oppositional defiant disorder (ODD) and conduct disorder (CD). The purpose of this study was to investigate the reliability and validity of teacher-rated symptoms of ODD and CD in a clinical sample. Methods: The sample comprised 421 children (84% boys; 6-17 years) diagnosed with ODD, CD, and/or attention deficit hyperactivity disorder (ADHD). Teachers completed a standardized ODD/CD symptom rating scale and the Teacher Report Form (TRF). Results: The reliability (internal consistency) of the symptom rating scale was high (alpha = 0.90). Convergent and divergent validity were demonstrated by substantial correlations with similar TRF syndrome scales and low-to-moderate correlations with dissimilar TRF scales. Discriminant validity was shown by the ability of the symptom rating scale to differentiate between children with ODD/CD and those with ADHD. Factorial validity was demonstrated by principal component analysis, which produced a two-factor solution that is largely consistent with the two-dimensional model of ODD and CD proposed by the Diagnostic and Statistical Manual of Mental Disorders (DSM)-IV-TR, although some CD symptoms representing aggressive behavior loaded on the ODD dimension. Conclusion: These findings suggest that DSM-IV-TR-based teacher rating scales are useful instruments for assessing disruptive behavior problems in children and adolescents. (C) 2014 S. Karger AG, Base

Parent-child inpatient treatment for children with behavioural and emotional disorders: a multilevel analysis of within-subjects effects

Background: The importance of parental involvement in child treatment is well-established. Several child psychiatric clinics have, therefore, set up inpatient family units where children and parents are both actively involved in the treatment. Unfortunately, evidence supporting the benefits of these units is sparse. Methods: We evaluated the effectiveness of inpatient treatment for families with severe parent-child interaction problems in a child psychiatric setting. Consecutive admissions to the parent-child ward (N = 66) were studied. A within-subjects design was used with four assessment points (baseline, admission, discharge, four-week follow-up). Outcome measures were 1) parent and teacher ratings of child behaviour, and 2) parent self-ratings of parenting practices, parental strains and parental mental health. Data were analyzed using multilevel modelling for longitudinal data (piecewise growth curve models). Results: All parent-rated measures improved significantly during the four-week treatment period (d = 0.4-1.3). These improvements were significantly greater than those observed during the four-week pre-admission period. In addition, benefits were maintained during the four-week follow-up period. Only parents' self-efficacy in managing their child's behaviour showed continued improvement during follow-up. Teacher ratings of children's disruptive behaviour at school were stable during the pre-admission period and showed significant improvements at follow-up (d = 0.3-0.4). Conclusions: We conclude that parent-child inpatient treatment has positive effects on child and parent behaviour and mental health, and can therefore be recommended for children with behavioural and emotional disorders and severe parent-child interaction problems

A comparison of orthographic processing in children with and without reading and spelling disorder in a regular orthography

Orthographic processing is a construct that encompasses the skills of recognizing, storing, accessing, and applying the print conventions of a writing system. Few studies have investigated orthographic processing in dyslexic children and it is not yet clear whether lexical and sublexical orthographic processing are both impaired in these children. The present study examined orthographic processing in dyslexic children (N = 19, below-average word reading as well as below average spelling skills, T-values < 40) and typically developing children (N = 32) aged 8-10 years. Different aspects of orthographic processing were measured. Word-specific knowledge (lexical level) was assessed with an Orthographic Choice Task. General orthographic knowledge (sublexical level) was assessed with three pseudoword tasks. The Freq-Choice-Task is a choice task that measures children's knowledge of frequent double consonants (e.g., nilemm-nilebb). The Pos-Choice-Task measures children's knowledge about legal positions of double consonants (e.g., sinnum-ssinum). The Pos-Speed-Task measures children's ability to identify orthographic irregularities in words presented singly (e.g., mmotin). Results show that dyslexic children are able to discriminate illegal/infrequent letter pattern from legal/frequent letter pattern. Seeing either a word with legal or illegal letter patterns singly (Pos-Speed-Task), dyslexic children show deficits in identifying illegal letter pattern as wrong, whereas they have no problems to identify legal letter pattern as correct. Furthermore, dyslexic children show a reduced word specific orthographic knowledge. Additionally, the present study demonstrated that word representations as well as sensitivity to legal letter pattern influence reading and spelling performance