Publications by authors named "Lisa Guy"

Nonphotochemical quenching (NPQ) is known to depress in vivo fluorescence (IVF) of chlorophyll a (Chla) in aquatic environments, which makes it difficult to interpret the hour-to-hour variations in Chla measured by in situ fluorometers. We hypothesized that ratios between quenched and unquenched IVF are a function of both NPQ and photochemical quenching. In this study, two diatom model species Thalassiosira pseudonana (CCMP1335) and Thalassiosira weissflogii (CCMP1047) incubated under a sinusoidal light:dark cycle were studied; IVF was recorded continuously, and Chla and photo-physiological variables were measured seven times a day.

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Background: Autism spectrum disorder (ASD) is a common and lifelong neurodevelopmental disorder with the hallmark features of social impairment and restricted and repetitive patterns of behaviour. Individuals with ASD often experience co-occurring mental health difficulties, some of which may obfuscate the ASD features themselves. Although there is a high need for mental health services for autistic adults, there are surprisingly few evidence-based treatments (EBTs) available; moreover, many mental health practitioners who are well-trained in EBTs shy away from treating autistic individuals due to lack of training in ASD.

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Both anxiety and autism spectrum disorder (ASD) are associated with atypical physiological activity. Few studies have systematically assessed the resting physiological activity in ASD with co-occurring anxiety disorders. We tested 75 participants divided in four groups: youth with ASD, with (ASD + Anxiety = 22, 6F, 12.

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Objective: To investigate the predictive power of comorbid attention-deficit/hyperactivity disorder (ADHD) symptoms on adaptive behavior skills in children who have an autism specrum disorder (ASD) diagnosis.

Method: This case-control study recruited 347 children from specialty clinics, primary care, and the community. Linear regression was used to test whether ADHD Rating Scale, Fourth Edition, scores of autistic children associated with poorer adaptive behavior scores, after controlling for the effects of age, intelligence, sex, and ASD symptom severity.

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Background: Children with autism spectrum disorder (ASD) and co-occurring attention-deficit/hyperactivity disorder (ADHD) symptoms have worse functional outcomes and treatment response than those without ADHD symptoms. There is limited knowledge of the neurobiology of ADHD symptoms in ASD. Here, we test the hypothesis that aberrant functional connectivity of two large-scale executive brain networks implicated in ADHD-the frontoparietal and salience/ventral attention networks-also play a role in ADHD symptoms in ASD.

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Many children with autism spectrum disorder display challenging behaviors. These behaviors are not limited to those with cognitive and/or language impairments. The Collaborative and Proactive Solutions framework proposes that challenging behaviors result from an incompatibility between environmental demands and a child's "lagging skills.

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Background: There is a lack of agreement about functional connectivity differences in individuals with autism spectrum disorder (ASD). Studies using absolute strength have found reduced connectivity, while those using relative strength--a measure of system topology--reveal mostly enhanced connectivity. We hypothesized that mixed findings may be driven by the metric of functional connectivity.

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Emotion regulation (ER) may be an important transdiagnostic factor for understanding mental and behavioral health given its association with several psychiatric disorders, including autism spectrum disorder (ASD). However, there is limited research on ER in ASD, particularly using biomarkers such as respiratory sinus arrhythmia (RSA). The aim of the current study was to examine RSA among school-aged children with ASD in relation to symptoms of anxiety, executive functioning, and adaptive socialization skills.

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Context: Best-estimate clinical diagnoses of specific autism spectrum disorders (autistic disorder, pervasive developmental disorder-not otherwise specified, and Asperger syndrome) have been used as the diagnostic gold standard, even when information from standardized instruments is available.

Objective: To determine whether the relationships between behavioral phenotypes and clinical diagnoses of different autism spectrum disorders vary across 12 university-based sites.

Design: Multisite observational study collecting clinical phenotype data (diagnostic, developmental, and demographic) for genetic research.

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Autism spectrum disorders (ASD) and schizophrenia are neurodevelopmental disorders for which recent evidence indicates an important etiologic role for rare copy number variants (CNVs) and suggests common genetic mechanisms. We performed cytogenomic array analysis in a discovery sample of patients with neurodevelopmental disorders referred for clinical testing. We detected a recurrent 1.

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Twenty avian influenza viruses were isolated from seven wild migratory bird species sampled at St. Lawrence Island, Alaska. We tested predictions based on previous phylogenetic analyses of avian influenza viruses that support spatially dependent trans-hemispheric gene flow and frequent interspecies transmission at a location situated at the Asian-North American interface.

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