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Plants exploit phenotypic plasticity to adapt their growth and development to prevailing environmental conditions. Interpretation of light and temperature signals is aided by the circadian system, which provides a temporal context. Phenotypic plasticity provides a selective and competitive advantage in nature but is obstructive during large-scale, intensive agricultural practices since economically important traits (including vegetative growth and flowering time) can vary widely depending on local environmental conditions. This prevents accurate prediction of harvesting times and produces a variable crop. In this study, we sought to restrict phenotypic plasticity and circadian regulation by manipulating signaling systems that govern plants' responses to environmental signals. Mathematical modeling of plant growth and development predicted reduced plant responses to changing environments when circadian and light signaling pathways were manipulated. We tested this prediction by utilizing a constitutively active allele of the plant photoreceptor phytochrome B, along with disruption of the circadian system via mutation of EARLY FLOWERING3. We found that these manipulations produced plants that are less responsive to light and temperature cues and thus fail to anticipate dawn. These engineered plants have uniform vegetative growth and flowering time, demonstrating how phenotypic plasticity can be limited while maintaining plant productivity. This has significant implications for future agriculture in both open fields and controlled environments., (Copyright © 2024 The Author. Published by Elsevier Inc. All rights reserved.)

Importance: Incidental findings (IFs) are unexpected abnormalities discovered during imaging and can range from normal anatomic variants to findings requiring urgent medical intervention. In the case of brain magnetic resonance imaging (MRI), reliable data about the prevalence and significance of IFs in the general population are limited, making it difficult to anticipate, communicate, and manage these findings., Objectives: To determine the overall prevalence of IFs in brain MRI in the nonclinical pediatric population as well as the rates of specific findings and findings for which clinical referral is recommended., Design, Setting, and Participants: This cohort study was based on the April 2019 release of baseline data from 11 810 children aged 9 to 10 years who were enrolled and completed baseline neuroimaging in the Adolescent Brain Cognitive Development (ABCD) study, the largest US population-based longitudinal observational study of brain development and child health, between September 1, 2016, and November 15, 2018. Participants were enrolled at 21 sites across the US designed to mirror the demographic characteristics of the US population. Baseline structural MRIs were centrally reviewed for IFs by board-certified neuroradiologists and findings were described and categorized (category 1, no abnormal findings; 2, no referral recommended; 3; consider referral; and 4, consider immediate referral). Children were enrolled through a broad school-based recruitment process in which all children of eligible age at selected schools were invited to participate. Exclusion criteria were severe sensory, intellectual, medical, or neurologic disorders that would preclude or interfere with study participation. During the enrollment process, demographic data were monitored to ensure that the study met targets for sex, socioeconomic, ethnic, and racial diversity. Data were analyzed from March 15, 2018, to November 20, 2020., Main Outcomes and Measures: Percentage of children with IFs in each category and prevalence of specific IFs., Results: A total of 11 679 children (52.1% boys, mean [SD] age, 9.9 [0.62] years) had interpretable baseline structural MRI results. Of these, 2464 participants (21.1%) had IFs, including 2013 children (17.2%) assigned to category 2, 431 (3.7%) assigned to category 3, and 20 (0.2%) assigned to category 4. Overall rates of IFs did not differ significantly between singleton and twin gestations or between monozygotic and dizygotic twins, but heritability analysis showed heritability for the presence or absence of IFs (h2 = 0.260; 95% CI, 0.135-0.387)., Conclusions and Relevance: Incidental findings in brain MRI and findings with potential clinical significance are both common in the general pediatric population. By assessing IFs and concurrent developmental and health measures and following these findings over the longitudinal study course, the ABCD study has the potential to determine the significance of many common IFs.

Background and Aims: Chronic alcohol use is associated with lower gray matter volume, and we reported recently that alcohol use showed negative associations with widespread gray matter (GM) volume even among young adults. The current study aimed to test the strength of association between (1) alcohol use and GM volume; (2) alcohol use and white matter (WM) integrity; (3) cannabis use and GM volume; and (4) cannabis use and WM integrity among adults and adolescents., Design and Setting: General linear models within large pooled cross-sectional samples of adolescents and adults who had participated in studies collecting substance use and neuroimaging data in the southwestern United States., Participants: The current analysis included adults aged 18-55 years (n = 853) and adolescents aged 14-18 years (n = 439) with a range of alcohol and cannabis use., Measurements: The dependent variable was GM volume or WM integrity, with key predictors of alcohol use [Alcohol Use Disorders Identification Test (AUDIT) score] and cannabis use (past 30-day use)., Findings: Alcohol use showed large clusters of negative associations (η p 2  = 0.028-0.145, P < 0.001) with GM volume among adults and to a lesser extent (one cluster; η p 2  = 0.070, P < 0.05) among adolescents. Large clusters showed significant associations (η p 2  = 0.050-0.124, P < 0.001) of higher alcohol use with poorer WM integrity, whereas adolescents showed no significant associations between alcohol use and WM. No associations were observed between structural measures and past 30-day cannabis use in adults or adolescents., Conclusions: Alcohol use severity is associated with widespread lower gray matter volume and white matter integrity in adults, and with lower gray matter volume in adolescents., (© 2017 Society for the Study of Addiction.)

Understanding youths' awareness and use of behavioral health services is important for improving services and engagement. Interviews and focus groups were conducted with students, parents, and teachers/staff in an urban area to understand awareness and use of a school's Native-tailored and -staffed school-based behavioral health center (NT-BHC) and community-based services. Results showed overwhelmingly positive responses regarding NT-BHC staff and services, with concerns focused on too few staff and services, and on privacy and confidentiality, as well as important differences in awareness and use of behavioral health services among youth, parents, and teachers/staff, valuable for improving engagement with and services for AI/AN youth.