19 research outputs found
Synchronous chaos and broad band gamma rhythm in a minimal multi-layer model of primary visual cortex
Visually induced neuronal activity in V1 displays a marked gamma-band
component which is modulated by stimulus properties. It has been argued that
synchronized oscillations contribute to these gamma-band activity [...
however,] even when oscillations are observed, they undergo temporal
decorrelation over very few cycles. This is not easily accounted for in
previous network modeling of gamma oscillations. We argue here that
interactions between cortical layers can be responsible for this fast
decorrelation. We study a model of a V1 hypercolumn, embedding a simplified
description of the multi-layered structure of the cortex. When the stimulus
contrast is low, the induced activity is only weakly synchronous and the
network resonates transiently without developing collective oscillations. When
the contrast is high, on the other hand, the induced activity undergoes
synchronous oscillations with an irregular spatiotemporal structure expressing
a synchronous chaotic state. As a consequence the population activity undergoes
fast temporal decorrelation, with concomitant rapid damping of the oscillations
in LFPs autocorrelograms and peak broadening in LFPs power spectra. [...]
Finally, we argue that the mechanism underlying the emergence of synchronous
chaos in our model is in fact very general. It stems from the fact that gamma
oscillations induced by local delayed inhibition tend to develop chaos when
coupled by sufficiently strong excitation.Comment: 49 pages, 11 figures, 7 table
The Impacts of Soil Microbial Communities on Translocated Sagebrush (\u3cem\u3eArtemisia tridentata\u3c/em\u3e) Seedlings Vary Along Gradients of pH but Not Organic Matter
Climate factors are often the focus of local adaptation studies, but there are additional biotic and abiotic factors, including microbial communities and soil properties, that may generate selection in plant populations. pH and soil organic matter (SOM) are important influencers of microbial communities. We investigated the influence of pH and SOM on plant-microbe interactions and local adaptation of big sagebrush to microbial communities. Sagebrush seeds and autoclaved soils from 4 sites were reciprocally transplanted in a greenhouse experiment. Half of these soils were treated with intact soil inoculum to identify microbial impacts and how these effects varied when sagebrush plants were translocated into new soils. Soil samples were tested for pH and organic matter to identify the abiotic factors that may drive local adaptation. Soil microbial communities influence sagebrush seedling survival negatively in more acidic soils and have weak positive effects in more alkaline soils. Sagebrush seedlings showed signs of local adaptation to microbial communities that come from soils similar to their home pH. There were no clear effects of SOM on seedling survival or influence of microbial communities at this life-history stage. This work has implications for the translocation of sagebrush seeds in restoration projects across the Great Basin
Caregiver Nutritional Health Outcomes of the Simple Suppers Study: Results from a 10 Week, Two-Group Quasi-Experimental Family Meals Intervention
Individuals from racial minority backgrounds, especially those in low income situations, are at increased risk for obesity. Family meals positively impact child nutritional health; however, there is limited evidence examining the impact on caregivers, particularly racial minority and income-restricted individuals. The objective of this intervention study was to determine the effect of Simple Suppers, a 10 week family meals program, on caregiver diet and nutrition outcomes. Intervention versus waitlist control participants were compared from baseline (T0) to post-intervention (T1). In addition, intervention participants were assessed at a 10 week follow-up time point (T2). This study was a two-group quasi-experimental intervention trial. Lessons (10 total) were delivered on a weekly basis for 90 min. Data were collected from intervention and waitlist control participants at T0 and T1, and intervention participants at T2. After baseline (T0) data collection, families enrolled in the immediate upcoming session of Simple Suppers (intervention group) or waited for 10 weeks (waitlist control group) to begin the program. Participants were caregivers of children ages 4–10 years. This study was conducted in a faith-based community center for underserved families in Columbus, Ohio. Primary outcomes were: diet quality assessed by Healthy Eating Index (HEI) total and component scores, and total energy intake (kcal/day); body mass index (BMI) (kg/m2), waist circumference (cm), systolic and diastolic blood pressure (BP) (mmHG); and self-efficacy for having healthy meals and menu planning (both scalar). The impact of the intervention (T0:T1) was assessed using generalized mixed-effects linear regression models. Maintenance of change in study outcomes among intervention participants (T1:T2) was examined with paired t-tests. 109 caregivers enrolled in this study. The retention rate at T1 was 90% (i.e., 98 participants). 56 of 68 intervention participants completed T2, resulting in a retention rate of 82%. Almost all (99%) were female, 61% were Black, and 50% were between 31 and 40 years old. In total, 40% had low income and 37% had low or very low food security. At T1, intervention vs. waitlist controls had a lower daily energy intake (p = 0.04), but an HEI-2010 component score for fatty acids (adequacy) that was lower indicating a lower dietary intake of fatty acids (p = 0.02), and a component score for empty calories (moderation) that was significantly lower indicating a higher intake of empty calorie foods (p = 0.03). At T1, intervention vs. waitlist controls also had a lower BMI (p < 0.001) and systolic BP (p = 0.04), and higher self-efficacy (p = 0.03). There were no group differences in other outcomes. At T2, intervention participants maintained the changes in daily energy intake, BMI, systolic BP, and self-efficacy that improved during the intervention period. There was no change (improvement) in the component score for fatty acids; however, the component score for empty calories significantly improved (p = 0.02). Engagement in the Simple Suppers program led to improvements in caregivers’ daily caloric intake, weight status, systolic blood pressure, and self-efficacy for family meals. Future research should further explore the dietary and nutritional health benefits of family meals among caregivers at the highest risk for obesity
Gyroresonant wave-particle interactions with chorus waves during extreme depletions of plasma density in the Van Allen radiation belts
Characterization of the Pediatric Acute-Onset Neuropsychiatric Syndrome Phenotype
Objective: Pediatric acute-onset neuropsychiatric syndrome (PANS) is a subtype of obsessive compulsive disorder (OCD) marked by an abrupt onset or exacerbation of neuropsychiatric symptoms. We aim to characterize the phenotypic presentation of youth with PANS.
Methods: Forty-three youth (ages 4–14 years) meeting criteria for PANS were assessed using self-report and clinician-administered measures, medical record reviews, comprehensive clinical evaluation, and laboratory measures.
Results: Youth with PANS presented with an early age of OCD onset (mean=7.84 years) and exhibited moderate to severe obsessive compulsive symptoms upon evaluation. All had comorbid anxiety and emotional lability, and scored well below normative means on all quality of life subscales. Youth with elevated streptococcal antibody titers trended toward having higher OCD severity, and presented more frequently with dilated pupils relative to youth without elevated titers. A cluster analysis of core PANS symptoms revealed three distinct symptom clusters that included core characteristic PANS symptoms, streptococcal-related symptoms, and cytokine-driven/physiological symptoms. Youth with PANS who had comorbid tics were more likely to exhibit a decline in school performance, visuomotor impairment, food restriction symptoms, and handwriting deterioration, and they reported lower quality of life relative to youth without tics.
Conclusions: The sudden, acute onset of neuropsychiatric symptoms, high frequency of comorbidities (i.e., anxiety, behavioral regression, depression, and suicidality), and poor quality of life capture the PANS subgroup as suddenly and severely impaired youth. Identifying clinical characteristics of youth with PANS will allow clinicians to diagnose and treat this subtype of OCD with a more strategized and effective approach
Characterization of the Pediatric Acute-Onset Neuropsychiatric Syndrome Phenotype
Objective: Pediatric acute-onset neuropsychiatric syndrome (PANS) is a subtype of obsessive compulsive disorder (OCD) marked by an abrupt onset or exacerbation of neuropsychiatric symptoms. We aim to characterize the phenotypic presentation of youth with PANS.
Methods: Forty-three youth (ages 4–14 years) meeting criteria for PANS were assessed using self-report and clinician-administered measures, medical record reviews, comprehensive clinical evaluation, and laboratory measures.
Results: Youth with PANS presented with an early age of OCD onset (mean=7.84 years) and exhibited moderate to severe obsessive compulsive symptoms upon evaluation. All had comorbid anxiety and emotional lability, and scored well below normative means on all quality of life subscales. Youth with elevated streptococcal antibody titers trended toward having higher OCD severity, and presented more frequently with dilated pupils relative to youth without elevated titers. A cluster analysis of core PANS symptoms revealed three distinct symptom clusters that included core characteristic PANS symptoms, streptococcal-related symptoms, and cytokine-driven/physiological symptoms. Youth with PANS who had comorbid tics were more likely to exhibit a decline in school performance, visuomotor impairment, food restriction symptoms, and handwriting deterioration, and they reported lower quality of life relative to youth without tics.
Conclusions: The sudden, acute onset of neuropsychiatric symptoms, high frequency of comorbidities (i.e., anxiety, behavioral regression, depression, and suicidality), and poor quality of life capture the PANS subgroup as suddenly and severely impaired youth. Identifying clinical characteristics of youth with PANS will allow clinicians to diagnose and treat this subtype of OCD with a more strategized and effective approach
Enteroaggregative Escherichia coli: surface protein dispersin increases bacterial uptake of ciprofloxacin
Characterization of the Pediatric Acute-Onset Neuropsychiatric Syndrome Phenotype
Objective: Pediatric acute-onset neuropsychiatric syndrome (PANS) is a subtype of obsessive compulsive disorder (OCD) marked by an abrupt onset or exacerbation of neuropsychiatric symptoms. We aim to characterize the phenotypic presentation of youth with PANS. Methods: Forty-three youth (ages 4–14 years) meeting criteria for PANS were assessed using self-report and clinician-administered measures, medical record reviews, comprehensive clinical evaluation, and laboratory measures. Results: Youth with PANS presented with an early age of OCD onset (mean=7.84 years) and exhibited moderate to severe obsessive compulsive symptoms upon evaluation. All had comorbid anxiety and emotional lability, and scored well below normative means on all quality of life subscales. Youth with elevated streptococcal antibody titers trended toward having higher OCD severity, and presented more frequently with dilated pupils relative to youth without elevated titers. A cluster analysis of core PANS symptoms revealed three distinct symptom clusters that included core characteristic PANS symptoms, streptococcal-related symptoms, and cytokine-driven/physiological symptoms. Youth with PANS who had comorbid tics were more likely to exhibit a decline in school performance, visuomotor impairment, food restriction symptoms, and handwriting deterioration, and they reported lower quality of life relative to youth without tics. Conclusions: The sudden, acute onset of neuropsychiatric symptoms, high frequency of comorbidities (i.e., anxiety, behavioral regression, depression, and suicidality), and poor quality of life capture the PANS subgroup as suddenly and severely impaired youth. Identifying clinical characteristics of youth with PANS will allow clinicians to diagnose and treat this subtype of OCD with a more strategized and effective approach