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Cardiovascular stress reactivity (CVR) is considered as a physiological pathway linking emotional reactivity and emotion regulation with psychopathology. However, the associations between CVR and emotional reactivity and emotion regulation remain underexplored, with limited evidence showing that either excessive or blunted CVR is associated with emotional reactivity and emotional regulation. Recently, moderate CVR has been theoretically hypothesized to be related to optimal outcomes; however, whether CVR is nonlinearly associated with emotional reactivity and emotion regulation still needs to be investigated. Parents of 341 junior school students reported their children’s emotional reactivity and emotion regulation on the Emotion Questionnaire, and the students were invited to participate in a mental arithmetic task with continuous cardiovascular monitoring indexed by heart rate (HR) and systolic and diastolic blood pressure (SBP, DBP). Results did not reveal any linear relationships between CVR and emotional reactivity or emotion regulation. However, quadratic associations between HR, SBP reactivity and emotional reactivity and emotion regulation were found even after controlling for sex, age and BMI. Specifically, there was a U-shaped association between HR, SBP reactivity, and emotional reactivity, while there was an inverted U-shaped association between HR, SBP reactivity, and emotion regulation. These findings suggest that moderate to high rather than exaggerated or blunted CVR reflects adaptive emotional reactivity and better emotion regulation among adolescents.

Selective hydrogenolysis of the aromatic carbon-oxygen (C-O) bonds in aryl ethers is an unsolved synthetic problem important for the generation of fuels and chemical feedstocks from biomass and for the liquefaction of coal. Currently, the hydrogenolysis of aromatic C-O bonds requires heterogeneous catalysts that operate at high temperature and pressure and lead to a mixture of products from competing hydrogenolysis of aliphatic C-O bonds and hydrogenation of the arene. Here, we report hydrogenolyses of aromatic C-O bonds in alkyl aryl and diaryl ethers that form exclusively arenes and alcohols. This process is catalyzed by a soluble nickel carbene complex under just 1 bar of hydrogen at temperatures of 80 to 120°C; the relative reactivity of ether substrates scale as Ar-OAr>>Ar-OMe>ArCH₂-OMe (Ar, Aryl; Me, Methyl). Hydrogenolysis of lignin model compounds highlights the potential of this approach for the conversion of refractory aryl ether biopolymers to hydrocarbons.

A new theory for the study of the reactivity in Organic Chemistry, named Molecular Electron Density Theory (MEDT), is proposed herein. MEDT is based on the idea that while the electron density distribution at the ground state is responsible for physical and chemical molecular properties, as proposed by the Density Functional Theory (DFT), the capability for changes in electron density is responsible for molecular reactivity. Within MEDT, the reactivity in Organic Chemistry is studied through a rigorous quantum chemical analysis of the changes of the electron density as well as the energies associated with these changes along the reaction path in order to understand experimental outcomes. Studies performed using MEDT allow establishing a modern rationalisation and to gain insight into molecular mechanisms and reactivity in Organic Chemistry.

Stress affects executive functions and exploring the association between stress-induced physiological reactivity and executive functions could highlight the potential mechanism of the stress-cognitive function link. Our study examined the linear and nonlinear associations between cardiovascular stress reactivity and cool and hot executive functions among adolescents. In November 2021 (T1), 273 Chinese adolescents between 11 and 14 ( M age = 12.93, SD age = 0.79) underwent a speech task during which their cardiovascular data were recorded, and they completed a Flanker task and an Emotional Stroop task. In May 2023 (T2), 253 adolescents again completed the Flanker and Emotional Stroop tasks. Cool and hot executive functions were assessed using the intra-individual reaction time variability of the Flanker task and Emotional Stroop task, respectively. Results showed that cardiovascular stress reactivity was positively linearly associated with cool executive functions at T1 and quadratically (inverted U -shaped) associated with cool executive functions at T1 and hot executive functions at T1 and T2. These findings suggest that compared to very high and very low cardiovascular reactivity, moderate to high cardiovascular reactivity to a structured social challenge is associated with better cool and hot executive functions.

Realizing the extraordinary potential of unactivated sp³ C-H bond oxidation in organic synthesis requires the discovery of catalysts that are both highly reactive and predictably selective. We report an iron (Fe)-based small molecule catalyst that uses hydrogen peroxide (H₂O₂) to oxidize a broad range of substrates. Predictable selectivity is achieved solely on the basis of the electronic and steric properties of the C-H bonds, without the need for directing groups. Additionally, carboxylate directing groups may be used to furnish five-membered ring lactone products. We demonstrate that these three modes of selectivity enable the predictable oxidation of complex natural products and their derivatives at specific C-H bonds with preparatively useful yields. This type of general and predictable reactivity stands to enable aliphatic C-H oxidation as a method for streamlining complex molecule synthesis.

Studies indicate that gut microbiota is related to neurodevelopmental and behavioral outcomes. Accordingly, early gut microbiota composition (GMC) has been linked to child temperament, but research is still scarce. The aim of this study was to examine how early GMC at 2.5 months is associated with child negative and fear reactivity at 8 and 12 months since they are potentially important intermediate phenotypes of later child psychiatric disorders. Our study population was 330 infants enrolled in the longitudinal FinnBrain Birth Cohort Study. Gut microbiota composition was analyzed using stool sample 16s rRNA sequencing. Negative and fear reactivity were assessed using the Laboratory Temperament Assessment Battery (Lab-TAB) at child's age of 8 months ( =150) and the Infant Behavior Questionnaire-Revised Short Form (IBQ-R SF) at child's age of 12 months ( = 276). We found a positive association between alpha diversity and reported fear reactivity and differing microbial community composition based on negative reactivity for boys. Isobutyric acid correlated with observed negative reactivity, however, this association attenuated in the linear model. Several genera were associated with the selected infant temperament traits. This study adds to the growing literature on links between infant gut microbiota and temperament informing future mechanistic studies.

Recent studies found that making judgments of learning (JOLs) can reactively facilitate memory, a phenomenon termed the reactivity effect of JOLs. The current study was designed to explore (1) whether making judgments of forgetting (JOFs) can also enhance memory and (2) whether there is any difference between the reactivity effects of JOFs and JOLs. Experiment 1 found that soliciting JOFs significantly enhanced retention of single words. Experiments 2 and 3 observed minimal difference in reactivity effects between JOFs and JOLs on learning of single words and word pairs. Finally, a meta-analysis was conducted to integrate results across studies to explore whether retention of items studied with JOLs differed from that of items studied with JOFs. The meta-analytic results showed minimal difference. Overall, the documented findings imply that (1) making JOFs reactively enhances memory, and (2) there is little difference in reactivity effects between JOFs and JOLs. These findings support the positive-reactivity theory to account for the reactivity effect.

The interaction of physical and mental vulnerability and environmental constraints is thought to foster the development of psychiatric disorders such as major depressive disorder (MDD). A central factor in the development of psychopathology is mental stress. Despite some evidence for parasympathetic withdrawal and sympathetic overactivity in MDD, the psychophysiological response to stress in depression is not clear-cut. Given the growing interest in heart rate and heart rate variability as indicators for remote monitoring of patients, it is important to understand how patients with MDD react to stress in a laboratory-controlled environment. We conducted a systematic review of studies using electrocardiography to derive heart rate and heart rate variability during stress in patients with clinical depression. We focused on well-validated stress tasks- the mental arithmetic stress task, the Trier social stress task and public speaking task- to minimize confounding effects due to the nature of the stressor. The majority of studies found hypo-reactivity during stress as a hallmark of depression as evidenced by lower fluctuation in heart rate and heart rate variability in the high-frequency band. We address the potential underlying biological mechanisms, the influence of covariates on these measures and briefly discuss the specificity and potential for remote monitoring by using these variables.