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Childhood overweight/obesity is associated with stress-related psychopathology, yet the pathways connecting childhood obesity to stress susceptibility are poorly understood. We employed a systems biology approach with 62 adolescent Lewis rats fed a Western-like high-saturated fat diet (WD, 41% kcal from fat) or a control diet (CD, 13% kcal from fat). A subset of rats underwent a 31-day model of predator exposures and social instability (PSS). Effects were assessed using behavioral tests, DTI (diffusion tensor imaging), NODDI (neurite orientation dispersion and density imaging), 16S rRNA gene sequencing for gut microbiome profiling, hippocampal microglia analysis, and targeted gene methylation. Parallel experiments on human microglia cells (HMC3) examined how palmitic acid influences cortisol-related inflammatory responses. Rats exposed to WD and PSS exhibited deficits in sociability, increased fear/anxiety-like behaviors, food consumption, and body weight. WD/PSS altered hippocampal microstructure (subiculum, CA1, dentate gyrus), and microbiome analysis showed a reduced abundance of members of the phylum Firmicutes. WD/PSS synergistically promoted neuroinflammatory changes in hippocampal microglia, linked with microbiome shifts and altered Fkbp5 expression/methylation. In HMC3, palmitate disrupted cortisol responses, affecting morphology, phagocytic markers, and cytokine release, partially mediated by FKBP5. This study identifies gene-environment interactions that influence microglia biology and may contribute to the connection between childhood obesity and stress-related psychopathology later in life.

Investigating task-based synchronous computer-mediated communication (SCMC) interaction has increasingly received scholarly attention. However, studies have focused on negotiation of meaning and the quantity, focus and resolution of language related episodes (LREs). This study aims to broaden our understanding of the role of audio, video, and text SCMC conditions by additionally examining second language (L2) learners' levels of engagement during the production of LREs as a result of interactive real-world tasks. We tested 52 dyads of L2 Spanish intermediate learners who completed a decision-making/writing task. Our main analysis revealed that dyads in the audio SCMC condition engaged in more limited LREs vis-à-vis the text SCMC group, and audio SCMC dyads also showed a trend of engaging more in elaborate LREs. The findings imply that interactive SCMC conditions can place differential demands on L2 learners, which has an effect on the ways in which L2 learners address LREs during task-based interaction.

Task-based research has investigated the learning opportunities (e.g. language related episodes) that emerge during heritage and second language learner interactions during writing tasks. However, to date, it is unknown how these peer interactions involving heritage language learners contribute to written texts. Further, given the rise of social technologies in educational settings, a need exists to examine how interactions in digital platforms affect the production of written texts. To address these issues, 13 heritage-second language learner and 16 heritage-heritage learner pairs enrolled in advanced Spanish content courses completed two distinct versions of writing tasks. Participants were instructed that they were hired as business consultants for clothing and cellphone companies in Spain. While each participant wrote her or his own version, the pairs had to interact to compose formal business letters in Spanish to the CEO of each company justifying the hiring (Task A) or laying off (Task B) of employees. The main results first revealed that heritage-heritage pairs produced more syntactically complex business letters, as evidenced by a greater ratio of syntactic subordination along with a minor trend of greater morphosyntactic accuracy. Second, synchronous computer-mediated communication interactions led to a higher production of syntactic coordination, especially for the heritage-second language pairs. Findings are discussed in light of the interplay between learner factors and task environment.

Childhood obesity leads to hippocampal atrophy and altered cognition. However, the molecular mechanisms underlying these impairments are poorly understood. The neurotrophic factor neuregulin-1 (NRG1) and its cognate ErbB4 receptor play critical roles in hippocampal maturation and function. This study aimed to determine whether exogenous NRG1 administration reduces hippocampal abnormalities and neuroinflammation in rats exposed to an obesogenic Western-like diet (WD). Lewis rats were randomly divided into four groups (12 rats/group): (1) control diet+vehicle (CDV); (2) CD + NRG1 (CDN) (daily intraperitoneal injections: 5 μg/kg/day; between postnatal day, PND 21-PND 41); (3) WD + VEH (WDV); (4) WD + NRG1 (WDN). Neurobehavioral assessments were performed at PND 43-49. Brains were harvested for MRI and molecular analyses at PND 49. We found that NRG1 administration reduced hippocampal volume (7%) and attenuated hippocampal-dependent cued fear conditioning in CD rats (56%). NRG1 administration reduced PSD-95 protein expression (30%) and selectively reduced hippocampal cytokine levels (IL-33, GM-CSF, CCL-2, IFN-γ) while significantly impacting microglia morphology (increased span ratio and reduced circularity). WD rats exhibited reduced right hippocampal volume (7%), altered microglia morphology (reduced density and increased lacunarity), and increased levels of cytokines implicated in neuroinflammation (IL-1α, TNF-α, IL-6). Notably, NRG1 synergized with the WD to increase hippocampal ErbB4 phosphorylation and the tumor necrosis alpha converting enzyme (TACE/ADAM17) protein levels. Although the results did not provide sufficient evidence to conclude that exogenous NRG1 administration is beneficial to alleviate obesity-related outcomes in adolescent rats, we identified a potential novel interaction between obesogenic diet exposure and TACE/ADAM17-NRG1-ErbB4 signaling during hippocampal maturation. Our results indicate that supraoptimal ErbB4 activities may contribute to the abnormal hippocampal structure and cognitive vulnerabilities observed in obese individuals.

BACKGROUND:Post-traumatic stress disorder (PTSD) and obesity are highly prevalent in adolescents. Emerging findings from our laboratory and others are consistent with the novel hypothesis that obese individuals may be predisposed to developing PTSD. Given that aberrant fear responses are pivotal in the pathogenesis of PTSD, the objective of this study was to determine the impact of an obesogenic Western-like high-fat diet (WD) on neural substrates associated with fear. METHODS:Adolescent Lewis rats (n = 72) were fed with either the experimental WD (41.4% kcal from fat) or the control diet. The fear-potentiated startle paradigm was used to determine sustained and phasic fear responses. Diffusion tensor imaging metrics and T2 relaxation times were used to determine the structural integrity of the fear circuitry including the medial prefrontal cortex (mPFC) and the basolateral complex of the amygdala (BLA). RESULTS:The rats that consumed the WD exhibited attenuated fear learning and fear extinction. These behavioral impairments were associated with oversaturation of the fear circuitry and astrogliosis. The BLA T2 relaxation times were significantly decreased in the WD rats relative to the controls. We found elevated fractional anisotropy in the mPFC of the rats that consumed the WD. We show that consumption of a WD may lead to long-lasting damage to components of the fear circuitry. CONCLUSIONS:Our findings demonstrate that consumption of an obesogenic diet during adolescence has a profound impact in the maturation of the fear neurocircuitry. The implications of this research are significant as they identify potential biomarkers of risk for psychopathology in the growing obese population.

Individual differences (IDs) largely contribute to success in adult second language attainment (e.g., Dörnyei, 2006). Heritage language (HL) studies have also explored the role of IDs, namely psychosocial variables, and biographical factors with an adult HL learner population. However, the specific contribution of these variables to HL learners' performance on linguistic tests that differ in degree of explicitness and modality remains unknown. Therefore, the current study tested 103 adult HL learners of Spanish who completed a spoken elicited imitation task (EIT) and a written untimed grammaticality judgment task (UGJT) that elicited their knowledge of vulnerable morphosyntactic structures in HL bilingual acquisition. To investigate the contribution of individual learner factors on their performance, participants completed a few questionnaires. Mixed-effects regression models revealed that sequential bilingual status, willingness to communicate, generation and motivation contributed significantly, but yet differentially to participants' performance on grammatical and ungrammatical items of the EIT and UGJT.

This paper presents a comparison between the acoustic scenario at the Rio de Janeiro city center, before and during the COVID-19 pandemic. Undergoing one of the most important pandemics of the recent history, the social isolation led to a new acoustic scenario for Rio de Janeiro. The study was realized at the city center, an area of historical, economic and cultural relevance. The comparison consisted of analyzing measured data and noise maps produced for the city center area. The maps were created according to measured and collected data of the respective time periods. The acoustic scenario prior to the pandemic time was reconstructed based on previous measurements and data collection, while the pandemic one was built with data survey during the highest social isolation index on July 2020. The comparative analysis showed a considerable noise reduction, between 10 and 15 dB, for areas where the traffic noise was not intense and where the human activities were predominant on the streets. However, there was no substantial noise decrease for the areas around the major avenues. This occurred due to the traffic intensity drop to 50% during the pandemic, which meant a noise reduction between 3 and 5 dB.

Psychological trauma and obesity co-occur frequently and have been identified as major risk factors for psychiatric disorders. Surprisingly, preclinical studies examining how obesity disrupts the ability of the brain to cope with psychological trauma are lacking. The objective of this study was to determine whether an obesogenic Western-like high-fat diet (WD) predisposes rats to post-traumatic stress responsivity. Adolescent Lewis rats (postnatal day 28) were fed ad libitum for 8 weeks with either the experimental WD diet (41.4% kcal from fat) or the control diet (16.5% kcal from fat). We modeled psychological trauma by exposing young adult rats to a cat odor threat. The elevated plus maze and the open field test revealed increased psychological trauma-induced anxiety-like behaviors in the rats that consumed the WD when compared with control animals 1 week after undergoing traumatic stress (p < 0.05). Magnetic resonance imaging showed significant hippocampal atrophy (20% reduction) and lateral ventricular enlargement (50% increase) in the animals fed the WD when compared with controls. These volumetric abnormalities were associated with behavioral indices of anxiety, increased leptin and FK506-binding protein 51 (FKBP51) levels, and reduced hippocampal blood vessel density. We found asymmetric structural vulnerabilities to the WD, particularly the ventral and left hippocampus and lateral ventricle. This study highlights how WD consumption during adolescence impacts key substrates implicated in post-traumatic stress disorder. Understanding how consumption of a WD affects the developmental trajectories of the stress neurocircuitry is critical, as stress susceptibility imposes a marked vulnerability to neuropsychiatric disorders.

This study compares metrics for environmental noise diagnosis in schools at airport vicinity. The goal is to analyze and identify the most suitable criteria for scaling aircraft noise impact over schools, during landing and take-off operations. A Brazilian case study is conducted, based on the noise mapping and sound level verification. The day-night average noise level (DNL) and the time above limit (TA) are investigated using acoustic simulation and noise mapping and in order to identify the critical receivers. Results of DNL and TA for two schools at airport surroundings show that the criteria adopted by the municipal and airport authorities to describe the airport noise are unsatisfactory and do not reflect the intermittent behavior of this type of noise. It was verified that individual receiver analysis, based on noise interruptions thought TA parameter is more suitable for evaluation of noise impact over schools at airport vicinity.