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We present an analytical model for measuring the dispersion of integrated waveguides, leveraging the Michelson interferometry effects observed in devices with chirped Bragg gratings. Building on our previous experimental work, we derived a theoretical framework that simulates the group delay and subsequent dispersion values from the reflected spectrum of a device under test (DUT) which is a linearly chirped Bragg grating fabricated on a silicon-on-insulator (SOI) platform. This model incorporates the principles of interference fringes generated by reflections within the waveguide, enabling a precise calculation of group delay (τ) in the DUT as a function of frequency. Our model predicts the dispersion by determining the spacing between the peaks (Δf) from the local period of the interferometric fringes, with τ being inversely proportional to Δf. Simulations were conducted on a DUT that is designed to produce a dispersion of -45.9 ps2. The model yielded a dispersion of -45.6 ± 0.67 ps2, demonstrating close alignment with both the theoretical design and our experimental results, which recorded a dispersion of -45.5 ± 11.2 ps2 from 7 different DUTs that were measured.

Autistic people experience high rates of co-occurring psychiatric diagnoses. Current prevalence estimates vary considerably due to an over-reliance on clinical cohorts and the longitudinal stability of diagnoses from childhood into adolescence is poorly understood. This study aims to provide prevalence rates of co-occurring DSM-5 psychiatric diagnosis for autistic adolescence and investigate, for the first time, the stability of diagnoses from childhood. Using a longitudinal stratified sample of autistic youth (N = 77; 13-17 years; 60% male), selected from a larger community-derived sample of those with pre-existing autism diagnoses (N = 277) weighted prevalence estimates of emotional (anxiety, depression), behavioural (oppositional and conduct disorders) and ADHD diagnoses were calculated based on semi-structured psychiatric interview. Prediction of adolescent psychiatric diagnosis based on childhood diagnostic status, sex, childhood IQ (both assessed at age 4-10 years) was tested. Emotional and behavioural disorders in adolescence were particularly prevalent, and significantly predicted by childhood disorder status. Attention-deficit/hyperactivity-disorder (ADHD) was prevalent but not predicted by childhood ADHD diagnosis. Neither sex nor childhood IQ predicted diagnostic outcomes. Autistic youth have high levels of co-occurring psychiatric conditions, which are broadly persistent across childhood and adolescence. Emotional disorders are particularly prevalent and remain persistent from childhood to adolescence. Greater diagnostic variability was found for ADHD with more adolescents moving across diagnostic thresholds., (© 2022. The Author(s).)

Lay Abstract: What is already known about the topic: The COVID-19 pandemic and the associated restrictions impacted all of society. There is emerging evidence showing a range of impacts on autistic children and young people and their families. Further research that looks at how individuals coped during the pandemic while considering how they were doing before the pandemic is needed. What this paper adds: This article explores whether how well autistic youth were doing before the pandemic influenced how they coped during the pandemic. It also looked at how well their parents were doing during the pandemic and whether any pre-pandemic factors influenced how they coped. Samples of both primary-school-aged autistic children and autistic teenagers and their parents were surveyed to answer these questions. More engagement and enjoyment in education provision during the pandemic and getting outside more were linked with better child and parental mental health during the pandemic. More attention deficit hyperactivity disorder before the pandemic was linked with more attention deficit hyperactivity disorder and behavioural problems during the pandemic in primary-school-aged autistic children, and more emotional problems during the pandemic in autistic teenagers. Parents with more mental health problems during the pandemic had more mental health problems before the pandemic. Implications for practice, research or policy: Encouraging engagement and enjoyment in education and promoting physical exercise are key intervention targets. Ensuring access to attention deficit hyperactivity disorder medication and support is important, especially if this is managed jointly across school and home.

Objective: Individuals with eating disorders are known to have higher rates of insecure attachment compared to community controls, but the factors underlying this finding are poorly understood. We conducted the first meta-analysis comparing attachment in eating disorder samples compared to community controls that included quality assessment, publication bias and moderation analysis., Method: We pre-registered our meta-analysis (CRD42019146799) and followed PRISMA guidelines. We searched PsychINFO, Embase, Medline, CINAHL, and Scopus for publications. Attachment scores were extracted, and Cohen's d calculated for each study using a random effects model., Results: In total, 35 studies were included in the meta-analysis and six studies were summarized in a narrative review. Eating disorder samples showed higher rates of insecure attachment compared to community controls, with a large effect size, across measurement methods and different attachment dimensions. Blinding of assessors moderated effect sizes for attachment interview studies, but no other moderators were significant., Discussion: Risk of insecure attachment is elevated in individuals with eating disorders, albeit heterogeneity is high and largely unexplained. Clinicians may need to take this into account in their work, particularly given the association between attachment insecurity and challenges to therapeutic alliance. Future studies comparing eating disorder samples with community samples should control for general psychopathology., Public Significance: Attachment is a broad concept referring to a person's thoughts, feelings and behaviors in relation to close others. This systematic review and meta-analysis found that individuals with eating disorders are lower in attachment security than community controls, regardless of attachment construct or measurement approach. Attachment may be relevant in influencing eating disorder recovery, the development of therapeutic alliance, and potentially clinical outcomes, although more research is needed., (© 2023 The Authors. International Journal of Eating Disorders published by Wiley Periodicals LLC.)

Objective: Despite the high prevalence of mental health difficulties in autistic youth, little is known about the patterns of developmental continuity and change in psychiatric symptoms between childhood and adolescence. Using a stratified community-derived sample of autistic youth (n = 101; 57 males, 44 females), within (homotypic) and between (heterotypic) domain associations between psychiatric symptoms in childhood to adolescence were tested as well as whether any continuities were moderated by sex, IQ, autism symptom severity, social economic status, or parental mental health., Method: Autistic youth were assessed for emotional, behavioral, and attention-deficit/hyperactivity disorder (ADHD) symptoms in childhood (age 4-9 years) and adolescence (age 13-17 years) using parental diagnostic interview. Unadjusted and adjusted (accounting for the co-occurrence of psychiatric symptoms in childhood) weighted models tested homotypic and heterotypic associations between symptoms in childhood and adolescence. Moderation of significant pathways was tested using multigroup analysis., Results: Adolescent psychiatric symptoms all were predicted by symptoms of their childhood counterparts (emotional symptoms incidence rate ratio [IRR] = 1.06, 95% CI = 1.02-1.10, p < .01; behavioral symptoms IRR = 1.38, 95% CI = 1.21-1.59, p < .01; ADHD symptoms IRR = 1.11, 95% CI = 1.05-1.19, p < .01); the only heterotypic pathway that remained significant in adjusted analyses was from childhood emotional symptoms to adolescent ADHD symptoms (IRR = 1.04, 95% CI = 1.01-1.07, p = .02). Sex moderated the homotypic ADHD symptoms pathway; associations were significant in female participants only. Child IQ moderated the homotypic behavioral symptoms pathway; the association was stronger in youth with IQ <70., Conclusion: Results from this community-based sample suggest that psychiatric symptoms in autistic youth exhibit substantial developmental continuity and thus highlight the importance of early screening and intervention. Sex and IQ may be important factors to consider when predicting likelihood of stability of ADHD and behavioral symptoms., (Copyright © 2022 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.)

Introduction: Self-harm and suicide are major public health concerns among children and adolescents. Many risk and protective factors for suicide and self-harm have been identified and reported in the literature. However, the capacity of these identified risk and protective factors to guide assessment and management is limited due to their great number. This protocol describes an ongoing systematic review and meta-analysis which aims to examine longitudinal studies of risk factors for self-harm and suicide in children and adolescents, to provide a comparison of the strengths of association of the various risk factors for self-harm and suicide and to shed light on those that require further investigation., Methods and Analysis: We perform a systematic search of the literature using the databases EMBASE, PsycINFO, Medline, CINAHL and HMIC from inception up to 28 October 2020, and the search will be updated before the systematic review publication. Additionally, we will contact experts in the field, including principal investigators whose peer-reviewed publications are included in our systematic review as well as investigators from our extensive research network, and we will search the reference lists of relevant reviews to retrieve any articles that were not identified in our search. We will extract relevant data and present a narrative synthesis and combine the results in meta-analyses where there are sufficient data. We will assess the risk of bias for each study using the Newcastle-Ottawa Scale and present a summary of the quantity and the quality of the evidence for each risk or protective factor., Ethics and Dissemination: Ethical approval will not be sought as this is a systematic review of the literature. Results will be published in mental health journals and presented at conferences focused on suicide prevention., Prospero Registration Number: CRD42021228212., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY. Published by BMJ.)

Adaptive functioning is lower in many autistic individuals to a greater extent than would be expected based on IQ. However, the clinical features associated with these difficulties are less well understood. This study examines longitudinal and contemporaneous associations of adaptive functioning in autistic youth across a wide ability range. Parent-reported autism symptoms, co-occurring emotional, behavioral and attention deficit hyperactivity disorder (ADHD) symptoms, and IQ were assessed in early childhood (M age 7 years; T1) and 6 years later in adolescence (M age 13 years; T2) in 179 autistic youth. Adaptive functioning was assessed at T2. Structural equation modeling estimated pathways to adaptive functioning from autism, and psychiatric symptoms at T1 and T2, testing whether associations were driven by continuity of behaviors from T1 to T2 or their contemporaneous effect at T2, or both, controlling for T1 IQ. Lower adaptive functioning at T2 was associated with higher T1 and T2 ADHD symptoms (β = -0.14, and β = -0.21) but not behavioral nor emotional symptoms at either timepoint. Lower adaptive functioning at T2 was also associated with lower T1 IQ (β = 0.43) and higher social communication symptoms (β = -0.37) at T2 but not T1, but the relationship with ADHD symptoms remained. Paths were not moderated by sex or IQ. Increased symptoms of ADHD, both in early childhood and contemporaneously, were associated with reduced adaptive functioning in adolescence. Co-occurring ADHD may be a modifiable risk factor for adaptive function impairments and should be routinely assessed and when present evidence-based treatments initiated which may benefit adaptive functioning outcomes. LAY SUMMARY: Adaptive functioning is lower in many autistic individuals to a greater extent than would be expected based on IQ. However, the clinical features associated with these difficulties are less well understood. In a community sample higher attention deficit/hyperactivity disorder (ADHD) symptoms, but not emotional or behavioral symptoms, in both early childhood and contemporaneously were associated with lower adaptive functioning in autistic adolescents. Co-occurring ADHD may be a modifiable risk factor for adaptive function difficulties in autism., (© 2022 The Authors. Autism Research published by International Society for Autism Research and Wiley Periodicals LLC.)

Research suggests an increased prevalence of callous-unemotional (CU) traits in children with autism spectrum disorder (ASD), and a similar impairment in fear recognition to that reported in non-ASD populations. However, past work has used measures not specifically designed to measure CU traits and has not examined whether decreased attention to the eyes reported in non-ASD populations is also present in individuals with ASD. The current paper uses a measure specifically designed to measure CU traits to estimate prevalence in a large community-based ASD sample. Parents of 189 adolescents with ASD completed questionnaires assessing CU traits, and emotional and behavioral problems. A subset of participants completed a novel emotion recognition task (n = 46). Accuracy, reaction time, total looking time, and number of fixations to the eyes and mouth were measured. Twenty-two percent of youth with ASD scored above a cut-off expected to identify the top 6% of CU scores. CU traits were associated with longer reaction times to identify fear and fewer fixations to the eyes relative to the mouth during the viewing of fearful faces. No associations were found with accuracy or total looking time. Results suggest the mechanisms that underpin CU traits may be similar between ASD and non-ASD populations.

Background: Irritability is a common and impairing occurrence in autistic youth, yet the underlying mechanisms are not well-known. In typically developing populations, differences in frustration response have been suggested as important driver of the behavioural symptoms of irritability. Research exploring the role of frustration response as a risk factor for irritability in autistic populations is limited and often uses parent report or observer ratings; objective measures of frustration response appropriate for use in autistic populations are required to advance the field., Methods: In the current study, fifty-two autistic adolescents aged 13-17 years from a population-based longitudinal study completed an experimental task designed to induce frustration through exposure to periods of unexpected delay. Behavioural (number of button presses) and physiological (heart rate; HR) metrics were collected during delay periods. Irritability was measured using the parent-rated Affective Reactivity Index (ARI). Analyses used mixed-level models to test whether irritability was associated with different slopes of behavioural and physiological response to experimentally induced frustration during the task. Age and baseline HR (for the physiological data only) were included as covariates., Results: Analyses showed a marginal association between irritability and the slope of behavioural response (incident rate ratio (IRR) =.98, p=.06), and a significant association with the slope of physiological response (b=-.10, p=.04); higher levels of irritability were associated with a dampened behavioural and physiological response, as indicated by flatter slopes of change over the course of the task. The pattern of results largely remained in sensitivity analyses, although the association with physiological response became non-significant when adjusting for IQ, autism symptom severity, and medication use (b=-.10, p=.10)., Conclusions: Results suggest that the current experimental task may be a useful objective measure of frustration response for use with autistic populations, and that a non-adaptive response to frustration may be one biological mechanism underpinning irritability in autistic youth. This may represent an important target for future intervention studies., (© 2021. The Author(s).)

Many autistic young people exhibit co-occurring behavior difficulties, characterized by conduct problems and oppositional behavior. However, the causes of these co-occurring difficulties are not well understood. Impairments in theory of mind (ToM) are often reported in autistic individuals and have been linked to conduct problems in nonautistic individuals. Whether an association between ToM ability and conduct problems exists in autistic populations, whether this association is similar between individuals who are autistic versus nonautistic, and whether these associations are specific to conduct problems (as opposed to other domains of psychopathology) remains unclear. ToM ability was assessed using the Frith-Happé Triangles task in a pooled sample of autistic (N = 128; mean age 14.78 years) and nonautistic youth (N = 50; mean age 15.48 years), along with parent-rated psychiatric symptoms of conduct problems, hyperactivity/inattention and emotional problems. Analyses tested ToM ability between autistic versus nonautistic participants, and compared associations between ToM performance and conduct problems between the two groups. Where no significant group differences in associations were found, the pooled association between ToM and conduct problems was estimated in the combined sample. Results showed no evidence of moderation in associations by diagnostic status, and an association between poorer ToM ability and higher levels of conduct problems, hyperactivity/inattention and emotional problems across the total sample. However, these associations became nonsignificant when adjusting for verbal IQ. Results provide support for theoretical models of co-occurring psychopathology in autistic populations, and suggest targets for intervention for conduct problems in autistic youth. LAY SUMMARY: Many young people with autism spectrum disorder show co-occurring behavior problems, but the causes of these are not well understood. This paper found an association between difficulties recognizing what others think and intend (so-called "theory of mind") in a simple animated task, and emotional and behavioral problems in autistic and nonautistic young people. However, a substantial part of this association was explained by individual differences in verbal ability. These findings may have implications for intervention efforts to improve young people's mental health., (© 2020 The Authors. Autism Research published by International Society for Autism Research and Wiley Periodicals LLC.)

Co-occurring emotional and behavioral problems (EBPs) frequently exist in young autistic children. There is evidence based on parental report that parenting interventions reduce child EBPs. More objective measures of child EBPs should supplement parent reported outcomes in trials. We describe the development of a new measure of child and parenting behavior, the Observation Schedule for Children with Autism-Anxiety, Behaviour and Parenting (OSCA-ABP). Participants were 83 parents/carers and their 4-8-year-old autistic children. The measure demonstrated good variance and potential sensitivity to change. Child and parenting behavior were reliably coded among verbal and minimally verbal children. Associations between reports from other informants and observed behavior showed the measure had sufficient convergent validity. The measure has promise to contribute to research and clinical practice in autism mental health beyond objective measurement in trials.

Objectives: Deep burst-suppressing isoflurane anesthesia regulates signaling pathways connected with antidepressant responses in the rodent brain: activation of TrkB neurotrophin receptor and inhibition of GSK3β kinase (glycogen synthase kinase 3β). The main objective of this study was to investigate whether EEG (electroencephalogram) burst suppression correlates with these intriguing molecular alterations induced by isoflurane., Methods: Adult male mice pre-implanted with EEG recording electrodes were subjected to varying concentrations of isoflurane (1.0-2.0% ad 20 min) after which medial prefrontal cortex samples were collected for molecular analyses, and the data retrospectively correlated to EEG (+/- burst suppression)., Results: Isoflurane dose-dependently increased phosphorylation of TrkB Y816 , CREB S133 (cAMP response element binding protein), GSK3β S9 and p70S6k T412/S424 . The time spent in burst suppression mode varied considerably between individual animals. Notably, a subset of animals subjected to 1.0-1.5% isoflurane showed no burst suppression. While p-GSK3β S9 , p-CREB S133 and p-p70S6k T412/S424 levels were increased in the samples obtained also from these animals, p-TrkB Y816 levels remained unaltered., Conclusions: Isoflurane dose-dependently regulates TrkB and GSK3β signaling and dosing associated with therapeutic outcomes in depressed patients produces most prominent effects., (Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: Many young people with autism spectrum disorder (ASD) experience emotional and behavioural problems. However, the causes of these co-occurring difficulties are not well understood. Perceptual processing atypicalities are also often reported in individuals with ASD, but how these relate to co-occurring emotional and behavioural problems remains unclear, and few studies have used objective measurement of perceptual processing., Methods: Event-related potentials (ERPs) were recorded in response to both standard and deviant stimuli (which varied in pitch) in an auditory oddball paradigm in adolescents (mean age of 13.56 years, SD = 1.12, range = 11.40-15.70) with ASD ( n  = 43) with a wide range of IQ (mean IQ of 84.14, SD = 24.24, range 27-129). Response to deviant as compared to standard stimuli (as indexed by the mismatch negativity (MMN)) and response to repeated presentations of standard stimuli (habituation) were measured. Multivariate regression tested the association between neural indices of perceptual processing and co-occurring emotional and behavioural problems., Results: Greater sensitivity to changes in pitch in incoming auditory information (discrimination), as indexed by increased MMN amplitude, was associated with higher levels of parent-rated behaviour problems. MMN amplitude also showed a trend positive correlation with parent-rated sensory hyper-sensitivity. Conversely, greater habituation at the later N2 component was associated with higher levels of emotional problems. Upon more detailed analyses, this appeared to be driven by a selectively greater ERP response to the first (but not the second or third) standard stimuli that followed deviant stimuli. A similar pattern of association was found with other measures of anxiety. All results remained in covariation analyses controlling for age, sex and IQ, although the association between MMN amplitude and behaviour problems became non-significant when controlling for ASD severity., Conclusions: Findings suggest that alterations in mechanisms of perceptual processing and discrimination may be important for understanding co-occurring emotional and behavioural problems in young people with ASD., Competing Interests: All participating families gave their written informed consent, and the study was approved by Camden and King’s Cross Ethics Sub-Committee (14/LO/2098).Not applicable.AP receives royalties from the Social Communication Questionnaire. The other authors declare that they have no competing interests.Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

The original version of this article contains additional supplementary material which was omitted during the initial submission and it was not published. These are graphical representations of the studies and effect sizes in each meta-analysis. Please note that there is no change to the main body of the article, data entered, or conclusions drawn from the meta-analyses.

This review (Prospero Registration Number: CRD42017057915) aimed to systematically identify and summarize existing research on the relationship between additional emotional and behavioral problems (EBP) in children with autism, and parenting stress (PS) and mental health problems (MHP) in their parents. Sixty-seven studies met criteria for inclusion in the review, 61 of which were included in the meta-analysis. Pooled correlation coefficients were in the low to moderate range ([Formula: see text]). Some evidence for moderation by measurement characteristics was found. Narrative review of concurrent adjusted associations showed some evidence for shared relationships with other factors, most notably ASD severity and parent perception of own parenting. Longitudinal studies showed mixed evidence for bidirectional predictive relationships between child EBP and parent psychological distress variables.