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Films of the Tl‐Ba‐Ca‐Cu‐O high‐Tc superconductor can be prepared by several organometallic chemical vapor deposition routes. Two of these involve Ba‐Ca‐Cu‐0 films that are first prepared using the volatile metal‐organic precursors Ba(heptafluorodimethyloctanedionate)2, Ca(dipivaloylmethanate)2, and Cu(acetylacetonate)2‐ Deposition is carried out at a pressure of 5 Torr with argon as the carrier gas and water vapor as the reactant gas. Thallium is next incorporated into these films either by organometallic chemical vapor deposition using Tl(cyclopentadienide) as the source, or by vapor diffusion using bulk Tl‐Ba‐Ca‐Cu‐O as the source. Thallium deposition is carried out at atmospheric pressure with an argon carrier and water‐saturated oxygen reactant gas, followed by rapid thermal annealing. Both procedures yield films that consist primarily of the TlBa2Ca2Cu3Ox phase, have preferential orientation of the Cu‐O planes parallel to the substrate surface, and exhibit onset of superconductivity at ∼125 K with zero resistance by 100 K.
We report here a plasma‐enhanced organometallic chemical vapor deposition process for the preparation of YBa2Cu3O7‐x thin films using two rf plasma coupling configurations. For the films grown under a direct plasma glow, the YBa2Cu3O7‐x phase is not found in the as‐deposited state. However, by employing plasma‐activated nitrous oxide as the reactant gas, superconducting YBa2Cu3O7‐x films having a low carbon content and a mirror‐like surface have been prepared in‐situ at a substrate temperature of 610°C using an organometallic chemical vapor deposition process.
Rett syndrome (RTT) is a severe neurodevelopmental disorder affecting females almost exclusively and is characterized by a wide spectrum of clinical manifestations. Mutations in the X-linked methyl-CpG-binding protein 2 (MECP2) gene have been found in up to 95% of classical RTT cases and a lesser proportion of atypical cases. Recently, mutations in another X-linked gene, CDKL5 (cyclin-dependent kinase-like 5) have been found to cause atypical RTT, in particular the early onset seizure (Hanefeld variant) and one female with autism. In this study we screened several cohorts of children for CDKL5 mutations, totaling 316 patients, including individuals with a clinical diagnosis of RTT but who were negative for MECP2 mutations (n = 102), males with X-linked mental retardation (n = 9), patients with West syndrome (n = 52), patients with autism (n = 59), patients with epileptic encephalopathy (n = 33), patients with Aicardi syndrome (n = 7) and other patients with intellectual disability with or without seizures (n = 54). In all, seven polymorphic variations and four de novo mutations (c.586C>T [p.S196L]; c.58G>C [p.G20R]; c.2504delC [p.P835fs]; deletion of exons 1 - 3) were identified, and in all instances of the latter the clinical phenotype was that of an epileptic encephalopathy. These results suggest that pathogenic CDKL5 mutations are unlikely to be identified in the absence of severe early-onset seizures and highlight the importance of screening for large intragenic and whole gene deletions.
We investigated gait in newly diagnosed children with autism. From our previous study with 6- to 14-year-olds, we hypothesized that motor symptoms indicative of basal ganglia and cerebellar dysfunction would appear across the developmental trajectory of autism. Two groups were recruited: children with autism (eight males, three females; mean age 5y 10mo [SD 9mo]; range 4y 4mo–6y 9mo) and a comparison group of typically developing children (eight males, three females; mean age 5y 9mo [SD 1y 1mo]; range 4y 3mo–7y 2mo). The GAITRite Walkway was used to gather data from average gait and intra-walk measurements. Experienced physiotherapists analyzed gait qualitatively. Groups were matched according to age, height, weight, and IQ; although not statistically significant, IQ was lower in the group with autism. Spatiotemporal gait data for children with autism were compatible with findings from patients with cerebellar ataxia: specifically, greater difficulty walking along a straight line, and the coexistence of variable stride length and duration. Children with autism were also less coordinated and rated as more variable and inconsistent (i.e. reduced smoothness) relative to the comparison group. Postural abnormalities in the head and trunk suggest additional involvement of the fronto-striatal basal ganglia region. Abnormal gait features are stable across key developmental periods and are, therefore, promising for use in clinical screening for autism.
Autism and Asperger's disorder (AD) are neurodevelopmental conditions that affect cognitive and social-communicative function. Using a movement-related potential (MRP) paradigm, we investigated the clinical and neurobiological issue of ‘disorder separateness’ versus ‘disorder variance’ in autism and AD. This paradigm has been used to assess basal ganglia/supplementary motor functioning in Parkinson's disease. Three groups (high functioning autism [HFA]: 16 males, 1 female; mean age 12y 5mo [SD 4y 4mo]; AD: 11 males, 2 females; mean age 13y 5mo [SD 3y 8mo]; comparison group: 13 males, 8 females; mean age 13y 10mo [SD 3y 11mo]) completed a cued motor task during electroencephalogram recording of MRPs. The HFA group showed reduced peak amplitude at Cz, indicating less activity over the supplementary motor area during movement preparation. Although an overall significant between-group effect was found for early slope and peak amplitude, sub-analysis revealed that the group with AD did not differ significantly from either group. However, it is suggested that autism and AD may be dissociated on the basis of brain–behaviour correlations of IQ with specific neurobiological measures. The overlap between MRP traces for autism and Parkinson's disease suggests that the neurobiological wiring of motor functioning in autism may bypass the supplementary motor area/primary motor cortex pathway.
Psychiatry has probably always been the least attractive of the medical specialties. The choice of psychiatry as a career has been consistently low in the English-speaking world over the past 50 years (British Medical Journal, 1973; Feifel et al, 1999; Brockington & Mumford, 2002). Over the past decade there has probably been a further decline in the proportion of medical graduates choosing to train in psychiatry (Sierles & Taylor, 1995; Feifel et al, 1999).
Anxiety is a highly prevalent problem with various manifestations in young children, especially those with an intellectual disability. Many parents of children with disabilities also experience a wide range of health problems, including anxiety, stress and depression. Very few group-based programs for parents of disabled children have been evaluated, and none of the existing research studies specifically address child or parental anxiety. Given the success of cognitive-behavioural interventions for anxious children without disabilities, it is logical that these interventions be applied to anxious intellectually disabled children. This paper presents a rationale for a new parent training-based early intervention program, targeting anxiety in this population of young people.
This study explored the claim that individuals with autism and Asperger's disorder tend to
process locally rather than holistically. Participants observed a large or “global” number
composed of smaller or “local” numbers. The response was contingent upon the
identification of either the large stimulus or the small stimuli. Relative to age, sex, and IQ
matched controls, global processing in children and adolescents with autism (N = 12) and
Asperger's disorder (N = 12) was more vulnerable when the local stimuli were incongruent.
The autism group made more global errors than their matched control group, regardless of
whether there was local incongruence. In contrast, the Asperger's disorder group made a
similar number of global errors as their respective control group. These results were
discussed in relation to an “absence of global precedence” notion, “weak central coherence”
theory, and right-hemisphere dysfunction. The neurobiological significance of these findings
were discussed in the context of a fronto-striatal model of dysfunction.
This article describes the application of cognitive behavioural therapy to three sexually abused young people. We emphasise developmental influences and the nuances of the therapeutic approach. An exposure-based treatment approach was used with the youths. A multimodal assessment evaluation was conducted at pretreatment and posttreatment, and at a 3-month follow-up. Results on outcome measures indicated a positive therapeutic effect for the youths.
This overview examines the nature, prevalence, and impact of child sexual abuse. Associations and potential risk factors are identified, thus showing that child sexual abuse is not randomly distributed through the population. Finally, we discuss the ways in which clinicians and researchers have conceptualised the impact of child sexual abuse. A social and developmental model is outlined.
Child sexual abuse is a highly prevalent problem that frequently occasions the onset of posttraumatic stress disorder in the victimised youngster. Given the success of cognitive-behavioral interventions with adult trauma victims, it has been suggested that this treatment approach be applied to sexually abused children. We review the empirical support for the efficacy and acceptability of cognitive-behavioral strategies in the treatment of sexually abused children. Several clinical practice and research issues are also noted.
Child sexual abuse is a prevalent form of child maltreatment that frequently occasions severe disturbance including posttraumatic stress disorder. This review focuses on recent cognitive-behavioural treatment initiatives designed specifically for sexually abused children, and the extent to which they are empirically supported. Our review draws on case studies, open clinical trials, multiple baseline investigations and randomized clinical trials. At first glance, the research findings are encouraging for the efficacy and acceptability of cognitive-behaviour therapy. However, more conservative conclusions are reached when stringent criteria are applied regarding evidentiary support for psychosocial interventions. Directions for future research are also explored.
The heterogeneous nature of school refusal has led to much confusion surrounding the conceptualisation of this phenomenon. A number of researchers have developed taxonomic systems in an effort to enhance our understanding of school refusal and to facilitate communication among professionals working in the field. The current paper explores the evolution of these systems and outlines the limitations of each. Non-empirical classificatory systems are reviewed first, followed by empirical systems based on factor analyses and diagnostic profiles. A functional taxonomic system for problematic school attendance is then reviewed. Future research based on sound methodological procedures should aim to examine a broad range of child and family characteristics in order to develop reliable, homogenous subtypes for this population.
This paper reviews the role and indications for pharmacotherapy of children with school refusal. The psychopharmacological treatment of school refusal is based mainly on evidence of the effectiveness of certain drugs in the treatment of adult disorders. There is some evidence that tricyclic antidepressants and benzobiazepines may be specifically useful in the treatment of school refusal, but further research is warranted. Potentially serious side effects mean that drugs are best confined to cases where psychological treatments have not been effective or where drugs are used briefly as an adjunct to a broader psychological treatment plan. Drugs may also have a role in the specific treatment of comorbid conditions associated with school refusal. Any use of drugs should involve regular reviews to monitor response, compliance, and side effects.
Traditionally, mental health professionals and school authorities have found school refusal to be a perplexing and challenging problem. Relevant to an understanding of school refusal, we initially review some important developmental-normative considerations. The clinical features, epidemiology, and etiology of school refusal are also briefly discussed. We then describe a number of behavioural strategies that have been used in the management of school refusal. Finally, we review the research support for the efficacy and acceptability of behavioural strategies in the treatment of school refusal.
In this study, we examined the prevalence and nature of nonclinical panic attacks in 649 Australian youth and explored the relations between such attacks and measures of social support, stress, anxiety, depression, and fear. Full-blown attacks (attacks involving four or more symptoms with rapid onset) were reported by 104 of the youth (16%). Attacks were reported more frequently by girls than boys; however, age was unrelated to panic-attack status. Heightened levels of anxiety and fear, as well as stress in the family and lack of family support, were related to attack status. Path-analytic procedures supported a working model consisting of stress, social support, and emotional distress as related to panic status. Limitations of the self-report data on panic attacks and the other measures used in this study are acknowledged.