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The dynamic model of the distributed propulsion vehicle faces significant challenges due to several factors. The primary difficulties arise from the strong coupling between multiple power units and aerodynamic rudder surfaces, the interaction between thrust and vehicle dynamics, and the complexity of the aerodynamic model, which includes high-dimensional and high-order variables. To address these challenges, wind tunnel tests are conducted to analyse the aerodynamic characteristics and identify variables affecting the aerodynamic coefficients. Subsequently, a deep neural network is employed to investigate the influence of the power system and aerodynamic rudder on the aerodynamic coefficients. Based on these findings, a multi-dynamic coupled aerodynamic model is developed. Furthermore, a control-oriented nonlinear dynamics model for the distributed propulsion vehicle is established, and a flight controller is designed. Finally, closed-loop simulations for the climb, descent and turn phases are performed, validating the effectiveness of the established model.
Brown dwarfs are failed stars with very low mass (13–75 Jupiter mass) and an effective temperature lower than 2 500 K. Their mass range is between Jupiter and red dwarfs. Thus, they play a key role in understanding the gap in the mass function between stars and planets. However, due to their faint nature, previous searches are inevitably limited to the solar neighbourhood (20 pc). To improve our knowledge of the low mass part of the initial stellar mass function and the star formation history of the Milky Way, it is crucial to find more distant brown dwarfs. Using James Webb Space Telescope (JWST) COSMOS-Web data, this study seeks to enhance our comprehension of the physical characteristics of brown dwarfs situated at a distance of kpc scale. The exceptional sensitivity of the JWST enables the detection of brown dwarfs that are up to 100 times more distant than those discovered in the earlier all-sky infrared surveys. The large area coverage of the JWST COSMOS-Web survey allows us to find more distant brown dwarfs than earlier JWST studies with smaller area coverages. To capture prominent water absorption features around 2.7 ${\unicode{x03BC}}$m, we apply two colour criteria, $\text{F115W}-\text{F277W}+1\lt\text{F277W}-\text{F444W}$ and $\text{F277W}-\text{F444W}\gt\,0.9$. We then select point sources by CLASS_STAR, FLUX_RADIUS, and SPREAD_MODEL criteria. Faint sources are visually checked to exclude possibly extended sources. We conduct SED fitting and MCMC simulations to determine their physical properties and associated uncertainties. Our search reveals 25 T-dwarf candidates and 2 Y-dwarf candidates, more than any previous JWST brown dwarf searches. They are located from 0.3 to 4 kpc away from the Earth. The spatial number density of 900–1 050 K dwarf is $(2.0\pm0.9) \times10^{-6}\text{ pc}^{-3}$, 1 050–1 200 K dwarf is $(1.2\pm0.7) \times10^{-6}\text{ pc}^{-3}$, and 1 200–1 350 K dwarf is $(4.4\pm1.3) \times10^{-6}\text{ pc}^{-3}$. The cumulative number count of our brown dwarf candidates is consistent with the prediction from a standard double exponential model. Three of our brown dwarf candidates were detected by HST, with transverse velocities $12\pm5$, $12\pm4$, and $17\pm6$ km s$^{-1}$. Along with earlier studies, the JWST has opened a new window of brown dwarf research in the Milky Way thick disk and halo.
We offer a novel motivational account of romantic love, which portrays it as a means to the end of feeling significant and worthy. According to the model, falling in love with a partner depends on the actor's perceptions that (1) the partner possesses meritorious characteristics, and (2) that they appreciate the actor and view them as significant. We assume that these two factors multiplicatively combine with the magnitude of actor's quest for significance to determine the likelihood of actor becoming enamored with partner. The multiplicative model has two major implications: 1. If any one of the partner's merit, appreciation, or actor's significance quest factors falls below its respective threshold of acceptability (such that it is subjectively non-existent), the likelihood of falling in love will be negligible. 2. Above their acceptability thresholds, levels of (partner's) merit, appreciation and (actor's) significance quest factors compensate for one another. A partner's lower standing on merit or appreciation is compensated in its impact on falling in love by the partner's higher standing on the remaining dimension. Furthermore, lower levels of either or both of these factors are compensated for by the actor's higher level of significance quest.
Our model affords a broad account of diverse love phenomena, allows the derivation of several specific hypotheses supported by prior close-relations research as well as new data, and it offers novel avenues for further research on classic issues in romantic love. The discussion considers our model's unique implications and examines its relation to other theories of love.
Metabolic enzymes are the catalysts that drive the biochemical reactions essential for sustaining life. Many of these enzymes are tightly regulated by feedback mechanisms. To fully understand their roles and modulation, it is crucial to investigate the relationship between their structure, catalytic mechanism, and function. In this perspective, by using three examples from our studies on Mycobacterium tuberculosis (Mtb) isocitrate lyase and related proteins, we highlight how an integrated approach combining structural, activity, and biophysical data provides insights into their biological functions. These examples underscore the importance of employing fast-fail experiments at the early stages of a research project, emphasise the value of complementary techniques in validating findings, and demonstrate how in vitro data combined with chemical, biochemical, and physiological knowledge can lead to a broader understanding of metabolic adaptations in pathogenic bacteria. Finally, we address the unexplored questions in Mtb metabolism and discuss how we expand our approach to include microbiological and bioanalytical techniques to further our understanding. Such an integrated and interdisciplinary strategy has the potential to uncover novel regulatory mechanisms and identify new therapeutic opportunities for the eradication of tuberculosis. The approach can also be broadly applied to investigate other biochemical networks and complex biological systems.
Understanding post-stroke spasticity (PSS) treatment in everyday clinical practice may guide improvements in patient care.
Methods:
This was a retrospective cohort study that used population-level administrative data. Adults (aged ≥18 years) who initiated PSS treatment (defined by the first PSS clinic visit, focal botulinum toxin injection, or anti-spasticity medication dispensation [baclofen, dantrolene and tizanidine] with none of these treatments occurring during the 2 years before the stroke) were identified between 2012 and 2019 in Alberta, Canada. Spasticity treatment use, time to treatment start and type of prescribing/treating physician were measured. Descriptive statistics were performed.
Results:
Within the cohort (n = 1,079), the most common PSS treatment was oral baclofen (initial treatment: 60.9%; received on/after the initial treatment date up to March 31, 2020: 69.0%), largely prescribed by primary care physicians (77.6%) and started a median of 348 (IQR 741) days after the stroke. Focal botulinum toxin (23.3%; 37.7%) was largely prescribed by physiatrists (72.2%) and started 311 (IQR 446) days after the stroke; spasticity clinic visits (18.6%; 23.8%) were also common.
Conclusions:
We found evidence of gaps in provision of spasticity management in persons with PSS including overuse of systemic oral baclofen (that has common adverse side effects and lacks evidence of effectiveness in PSS) and potential underuse of focal botulinum toxin injections. Further investigation and strategies should be pursued to improve alignment of PSS treatment with guideline recommendations that in turn will support better outcomes for those with PSS.
Emerging evidence suggests that routine physical activity may improve exercise capacity, long-term outcomes, and quality of life in individuals with Fontan circulation. Despite this, it is unclear how active these individuals are and what guidance they receive from medical providers regarding physical activity. The aim of this study was to survey Fontan patients on personal physical activity behaviours and their cardiologist-directed physical activity recommendations to set a baseline for future targeted efforts to improve this.
Methods:
An electronic survey assessing physical activity habits and cardiologist-directed guidance was developed in concert with content experts and patients/parents and shared via a social media campaign with Fontan patients and their families.
Results:
A total of 168 individuals completed the survey. The median age of respondents was 10 years, 51% identifying as male. Overall, 21% of respondents spend > 5 hours per week engaged in low-exertion activity and only 7% spend > 5 hours per week engaged in high-exertion activity. In all domains questioned, pre-adolescents reported higher participation rates than adolescents. Nearly half (43%) of respondents reported that they do not discuss activity recommendations with their cardiologist.
Conclusions:
Despite increasing evidence over the last two decades demonstrating the benefit of exercise for individuals living with Fontan circulation, only a minority of patients report engaging in significant amounts of physical activity or discussing activity goals with their cardiologist. Specific, individualized, and actionable education needs to be provided to patients, families, and providers to promote and support regular physical activity in this patient population.
Adolescence is a period marked by highest vulnerability to the onset of depression, with profound implications for adult health. Neuroimaging studies have revealed considerable atrophy in brain structure in these patients with depression. Of particular importance are regions responsible for cognitive control, reward, and self-referential processing. However, the causal structural networks underpinning brain region atrophies in adolescents with depression remain unclear.
Objectives
This study aimed to investigate the temporal course and causal relationships of gray matter atrophy within the brains of adolescents with depression.
Methods
We analyzed T1-weighted structural images using voxel-based morphometry in first-episode adolescent patients with depression (n=80, 22 males; age = 15.57±1.78) and age, gender matched healthy controls (n=82, 25 males; age = 16.11±2.76) to identify the disease stage-specific gray matter abnormalities. Then, with granger causality analysis, we arranged the patients’ illness duration chronologically to construct the causal structural covariance networks that investigated the causal relationships of those atypical structures.
Results
Compared to controls, smaller volumes in ventral medial prefrontal cortex (vmPFC), dorsal anterior cingulate cortex (dACC), middle cingulate cortex (MCC) and insula areas were identified in patients with less than 1 year illness duration, and further progressed to the subgenual ACC, regions of default, frontoparietal networks in longer duration. Causal network results revealed that dACC, vmPFC, MCC and insula were prominent nodes projecting exerted positive causal effects to regions of the default mode and frontoparietal networks. The dACC, vmPFC and insula also had positive projections to the reward network, which included mainly the thalamus, caudate and putamen, while MCC also exerted a positive causal effect on the insula and thalamus.
Conclusions
These findings revealed the progression of structural atrophy in adolescent patients with depression and demonstrated the causal relationships between regions involving cognitive control, reward and self-referential processes.
The occurrence of depression in adolescence, a critical period of brain development, linked with neuroanatomical and cognitive abnormalities. Neuroimaging studies have identified hippocampal abnormalities in those of adolescent patients. However, few studies have investigated the atypically developmental trends in hippocampal subfields in adolescents with depression and their relationships with cognitive dysfunctions.
Objectives
To explore the structural abnormalities of hippocampal subfields in patients with youth depression and examine how these abnormalities associated with cognitive deficits.
Methods
We included a sample of 79 first-episode depressive patients (17 males, age = 15.54±1.83) and 71 healthy controls (23 males, age = 16.18±2.85). The severity of these adolescent patients was assessed by depression scale, suicidal risk and self-harm behavior. Nine cognitive tasks were used to evaluate memory, cognitive control and attention abilities for all participants. Bilateral hippocampus were segmented into 12 subfields with T1 and T2 weighted images using Freesurfer v6.0. A mixed analysis of variance was performed to assess the differences in subfields volumes between all patients and controls, and between patients with mild and severe depression. Finally, LASSO regression was conducted to explore the associations between hippocampal subfields and cognitive abnormalities in patients.
Results
We found significant subfields atrophy in the CA1, CA2/3, CA4, dentate gyrus, hippocampal fissure, hippocampal tail and molecular layer subfields in patients. For those patients with severe depression, hippocampal subfields showed greater extensive atrophy than those in mild, particularly in CA1-4 subfields extending towards the subiculum. These results were similar across various severity assessments. Regression indicated that hippocampal subfields abnormalities had the strongest associations with memory dysfunction, and relatively week associations with cognitive control and attention. Notably, CA4 and dentate gyrus had the highest weights in the regression model.
Conclusions
As depressive severity increases, hippocampal subfield atrophy tends to spread from CA regions to surrounding areas, and primarily affects memory function in patients with youth depression. These results suggest hippocampus might be markers in progression of adolescent depression, offering new directions for early clinical intervention.
Although behavioral mechanisms in the association among depression, anxiety, and cancer are plausible, few studies have empirically studied mediation by health behaviors. We aimed to examine the mediating role of several health behaviors in the associations among depression, anxiety, and the incidence of various cancer types (overall, breast, prostate, lung, colorectal, smoking-related, and alcohol-related cancers).
Methods
Two-stage individual participant data meta-analyses were performed based on 18 cohorts within the Psychosocial Factors and Cancer Incidence consortium that had a measure of depression or anxiety (N = 319 613, cancer incidence = 25 803). Health behaviors included smoking, physical inactivity, alcohol use, body mass index (BMI), sedentary behavior, and sleep duration and quality. In stage one, path-specific regression estimates were obtained in each cohort. In stage two, cohort-specific estimates were pooled using random-effects multivariate meta-analysis, and natural indirect effects (i.e. mediating effects) were calculated as hazard ratios (HRs).
Results
Smoking (HRs range 1.04–1.10) and physical inactivity (HRs range 1.01–1.02) significantly mediated the associations among depression, anxiety, and lung cancer. Smoking was also a mediator for smoking-related cancers (HRs range 1.03–1.06). There was mediation by health behaviors, especially smoking, physical inactivity, alcohol use, and a higher BMI, in the associations among depression, anxiety, and overall cancer or other types of cancer, but effects were small (HRs generally below 1.01).
Conclusions
Smoking constitutes a mediating pathway linking depression and anxiety to lung cancer and smoking-related cancers. Our findings underline the importance of smoking cessation interventions for persons with depression or anxiety.
The assessment of seed quality and physiological potential is essential in seed production and crop breeding. In the process of rapid detection of seed viability using tetrazolium (TZ) staining, it is necessary to spend a lot of labour and material resources to explore the pretreatment and staining methods of hard and solid seeds with physical barriers. This study explores the TZ staining methods of six hard seeds (Tilia miqueliana, Tilia henryana, Sassafras tzumu, Prunus subhirtella, Prunus sibirica, and Juglans mandshurica) and summarizes the TZ staining conditions required for hard seeds by combining the difference in fat content between seeds and the kinship between species, thus providing a rapid viability test method for the protection of germplasm resources of endangered plants and the optimization of seed bank construction. The TZ staining of six species of hard seeds requires a staining temperature above 35 °C and a TZ solution concentration higher than 1%. Endospermic seeds require shorter staining times than exalbuminous seeds. The higher the fat content of the seeds, the lower the required incubation temperature and TZ concentration for staining, and the longer the staining time. And the closer the relationship between the two species, the more similar their staining conditions become. The TZ staining method of similar species can be predicted according to the genetic distance between the phylogenetic trees, and the viability of new species can be detected quickly.
Limited evidence exists regarding care pathways for stroke survivors who do and do not receive poststroke spasticity (PSS) treatment.
Methods:
Administrative data was used to identify adults who experienced a stroke and sought acute care between 2012 and 2017 in Alberta, Canada. Pathways of stroke care within the health care system were determined among those who initiated PSS treatment (PSS treatment group: outpatient pharmacy dispensation of an anti-spastic medication, focal chemo-denervation injection, or a spasticity tertiary clinic visit) and those who did not (non-PSS treatment group). Time from the stroke event until spasticity treatment initiation, and setting where treatment was initiated were reported. Descriptive statistics were performed.
Results:
Health care settings within the pathways of stroke care that the PSS (n = 1,079) and non-PSS (n = 22,922) treatment groups encountered were the emergency department (86 and 84%), acute inpatient care (80 and 69%), inpatient rehabilitation (40 and 12%), and long-term care (19 and 13%), respectively. PSS treatment was initiated a median of 291 (interquartile range 625) days after the stroke event, and most often in the community when patients were residing at home (45%), followed by “other” settings (22%), inpatient rehabilitation (18%), long-term care (11%), and acute inpatient care (4%).
Conclusions:
To our knowledge, this is the first population based cohort study describing pathways of care among adults with stroke who subsequently did or did not initiate spasticity treatment. Areas for improvement in care may include strategies for earlier identification and treatment of PSS.
Redox and acid-base reactions play important roles in the fate of metal contaminants in soils and sediments. The presence of significant amounts of Cr, Pb and other toxic heavy metals in contaminated soils and sediments is of great environmental concern. Oxidation states and dissolution characteristics of the heavy metals can exert negative effects on the natural environment. Atomic force microscopy (AFM) was used to follow the changes in morphology and structure of reaction products of Cr and Pb formed on mineral surfaces. Nitrate salts of Cr(III) and Pb(II) were used to replace the native exchangeable cations on muscovite and smectite surfaces and the metal-mineral systems were then reacted at different pH's and redox conditions.
For Pb, aggregate morphological forms were found at pH 6.1 and 12.4. At pH 6.1, the mean roughness value was 0.70 nm, and at pH 12.4 it was 5.30 nm. The fractal dimensions were 2.03 at pH 6.1 and 2.05 at pH 12.4. For Cr(III), both layered and aggregate morphological forms were found at pH 6.8 and 10.8. The mean roughness values were 0.90 nm at pH 6.8 and 4.3 nm at pH 10.8. Fractal dimensions for both were 2.00. The effect of redox conditions on morphological characteristics was studied on a smectite substrate. The reduced clays were more compacted than oxidized ones and the reduced clay could reduce Cr(VI) to Cr(III), forming new minerals on the surfaces.
A geochemical equilibrium model, MINTEQA2, was used to simulate the experimental conditions and predict possible reaction products. Simulation results agreed well with data from experiments, providing evidence that modeling can provide a useful “reality check” for such studies. Together, MINTEQA2 and AFM can provide important information for evaluating the morphologies and chemical reactivities of metal reaction products formed on phyllosilicate surfaces under varying environmental conditions.
Redox properties of iron-bearing mineral surfaces may play an important role in controlling the transport and transformation of pollutants into ground waters. Suspensions of seven iron-bearing minerals were reacted with pH and redox indicators under anaerobic conditions at the pH of the natural suspension. The responses of the indicators to the mineral surfaces were monitored by UV-visible spectroscopy using a scattered transmission technique. The Hammett surface acidity function (Hs) and the surface redox potential (Ehs) of these iron-bearing minerals were measured. These measured values were used to calculate Eh values for the seven minerals: goethite = +293 mV; chlorite = +290 mV; hematite = +290 mV; almandite = +282 mV; ferruginous smectite = +275 mV; pyrite = +235 mV; and Na-vermiculite = +223 mV. Calculated surface redox potentials of minerals are different from their potentials measured by platinum electrode in bulk suspensions. UV-visible spectroscopy provides a quick and non-destructive way of monitoring organic probe response at the mineral surface.
Internalising disorders are highly prevalent emotional dysregulations during preadolescence but clinical decision-making is hampered by high heterogeneity. During this period impulsivity represents a major risk factor for psychopathological trajectories and may act on this heterogeneity given the controversial anxiety–impulsivity relationships. However, how impulsivity contributes to the heterogeneous symptomatology, neurobiology, neurocognition and clinical trajectories in preadolescent internalising disorders remains unclear.
Aims
The aim was to determine impulsivity-dependent subtypes in preadolescent internalising disorders that demonstrate distinct anxiety–impulsivity relationships, neurobiological, genetic, cognitive and clinical trajectory signatures.
Method
We applied a data-driven strategy to determine impulsivity-related subtypes in 2430 preadolescents with internalising disorders from the Adolescent Brain Cognitive Development study. Cross-sectional and longitudinal analyses were employed to examine subtype-specific signatures of the anxiety–impulsivity relationship, brain morphology, cognition and clinical trajectory from age 10 to 12 years.
Results
We identified two distinct subtypes of patients who internalise with comparably high anxiety yet distinguishable levels of impulsivity, i.e. enhanced (subtype 1) or decreased (subtype 2) compared with control participants. The two subtypes exhibited opposing anxiety–impulsivity relationships: higher anxiety at baseline was associated with higher lack of perseverance in subtype 1 but lower sensation seeking in subtype 2 at baseline/follow-up. Subtype 1 demonstrated thicker prefrontal and temporal cortices, and genes enriched in immune-related diseases and glutamatergic and GABAergic neurons. Subtype 1 exhibited cognitive deficits and a detrimental trajectory characterised by increasing emotional/behavioural dysregulations and suicide risks during follow-up.
Conclusions
Our results indicate impulsivity-dependent subtypes in preadolescent internalising disorders and unify past controversies about the anxiety–impulsivity interaction. Clinically, individuals with a high-impulsivity subtype exhibit a detrimental trajectory, thus early interventions are warranted.
THIS ARTICLE EXAMINES practices of commentary in Graeco-Roman antiquity and their dominant receptions in modern and contemporary scholarship. We consider philological activity based primarily in Alexandria and Rome from the third century bCe to the fifth century Ce and concentrate on the so-called Alexandrian mode of commen-tary, especially that associated with Aristarchus of Samothrace (ca. 216–ca. 145 bCe), which has occupied a preeminent place in studies of ancient commentary. In the process, we highlight alternative commentarial modes that have been relegated to the margins in mainstream accounts, precisely for their departure from the chief strategies associ-ated with Alexandrian literary critical practices. We contend that both ancient schol-ars and modern classicists have, for debatable reasons, privileged these Alexandrian (or Aristarchan) practices of commentary while perpetuating the suppression of other styles of scholarship that circulated in antiquity, late antiquity, and the medieval period. Our aim is to illuminate some of the processes and prejudices that have informed these scholarly choices and to investigate the conditions under which understandings and practices of commentary became so centred around Alexandria. Interrogating one of the most tenacious master narratives about ancient Greek and Roman commentary will uncover the norms and categories of analysis that have long guided understandings and practices of commentary in Classics and in adjacent fields.
Graeco-Roman Commentary: An Overview
Classicists have construed the philological activity of the Alexandrian scholars as the pinnacle of ancient classical scholarship, as well as the fons et origo of modern literary criticism in its ideal form. As Franco Montanari observes: “Although much progress still remained to be made, and Wolfian scientific philology, the modern critical edition and the scientific commentary were still in the distant future… a nodal step had been taken in the period from Zenodotus to Aristarchus.” The preeminent historian Peter Fraser, moreover, remarks that “the main feature of post-Aristarchean scholarship is the enor-mous influence which Aristarchus’ work continued to exert.”
Alexandria's reputation as the centre of erudition par excellence has rested on the fame of its library, which operated under Ptolemaic patronage and attracted intellectu-als across the Greek-speaking world who wished to gain access to its scholarly commu-nity and vast collections of books. The copying, correcting, interpreting, and canonizing of Greek literature, not only of Homer but also of other archaic and classical writers (ca. seventh to fourth century bCe), received the greatest attention there.
Over the past decade, transdiagnostic indicators in relation to neurobiological processes have provided extensive insight into youth’s risk for psychopathology. During development, exposure to childhood trauma and dysregulation (i.e., so-called AAA symptomology: anxiety, aggression, and attention problems) puts individuals at a disproportionate risk for developing psychopathology and altered network-level neural functioning. Evidence for the latter has emerged from resting-state fMRI studies linking mental health symptoms and aberrations in functional networks (e.g., cognitive control (CCN), default mode networks (DMN)) in youth, although few of these investigations have used longitudinal designs. Herein, we leveraged a three-year longitudinal study to identify whether traumatic exposures and concomitant dysregulation trigger changes in the developmental trajectories of resting-state functional networks involved in cognitive control (N = 190; 91 females; time 1 Mage = 11.81). Findings from latent growth curve analyses revealed that greater trauma exposure predicted increasing connectivity between the CCN and DMN across time. Greater levels of dysregulation predicted reductions in within-network connectivity in the CCN. These findings presented in typically developing youth corroborate connectivity patterns reported in clinical populations, suggesting there is predictive utility in using transdiagnostic indicators to forecast alterations in resting-state networks implicated in psychopathology.
Second language learners’ reading is less efficient and more effortful than native reading. However, the source of their difficulty is unclear; L2 readers might struggle with reading in a different orthography, or they might have difficulty with later stages of linguistic interpretation of the input, or both. The present study explored the source of L2 reading difficulty by analyzing the distribution of fixation durations in reading. In three studies, we observed that L2 readers experience an increase in Mu, which we interpret as indicating early orthographic processing difficulty, when the L2 has a significantly different writing system than the L1 (e.g., Chinese and English) but not when the writing systems were similar (e.g., Portuguese and English). L2 readers also experienced an increase in Tau, indicating later-arising processing difficulty which likely reflects later-stage linguistic processes, when they read for comprehension. L2 readers of Chinese also experienced an additional increase in Tau.
Trait dissociation has not been examined from a structural human brain mapping perspective in healthy adults or children. Non-pathological dissociation shares some features with daydreaming and mind-wandering, but also involves subtle disruptions in affect and autobiographical memory.
Aims
To identify neurostructural biomarkers of trait dissociation in healthy children.
Method
Typically developing 9- to 15-year-olds (n = 180) without psychological or behavioural disorders were enrolled in the Developmental Chronnecto-Genomics (DevCoG) study of healthy brain development and completed psychological assessments of trauma exposure and dissociation, along with a structural T1-weighted magnetic resonance imaging. We conducted univariate ANCOVA generalised linear models for each region of the default mode network examining the effects of trait dissociation, including scanner site, age, gender and trauma as covariates and correcting for multiple comparison.
Results
We found that the precuneus was significantly larger in children with higher levels of trait dissociation but this was not related to trauma exposure. The inferior parietal volume was smaller in children with higher levels of trauma but was not related to dissociation. No other regions of interest, including frontal and limbic structures, were significantly related to trait dissociation even before multiple comparison correction.
Conclusions
Trait dissociation reflects subtle cognitive disruptions worthy of study in healthy people and warrants study as a potential risk factor for psychopathology. This neurostructural study of trait dissociation in healthy children identified the precuneus as an essential brain region to consider in future dissociation research.
Mental health was only modestly affected in adults during the early months of the COVID-19 pandemic on the group level, but interpersonal variation was large.
Aims
We aim to investigate potential predictors of the differences in changes in mental health.
Method
Data were aggregated from three Dutch ongoing prospective cohorts with similar methodology for data collection. We included participants with pre-pandemic data gathered during 2006–2016, and who completed online questionnaires at least once during lockdown in The Netherlands between 1 April and 15 May 2020. Sociodemographic, clinical (number of mental health disorders and personality factors) and COVID-19-related variables were analysed as predictors of relative changes in four mental health outcomes (depressive symptoms, anxiety and worry symptoms, and loneliness), using multivariate linear regression analyses.
Results
We included 1517 participants with (n = 1181) and without (n = 336) mental health disorders. Mean age was 56.1 years (s.d. 13.2), and 64.3% were women. Higher neuroticism predicted increases in all four mental health outcomes, especially for worry (β = 0.172, P = 0.003). Living alone and female gender predicted increases in depressive symptoms and loneliness (β = 0.05–0.08), whereas quarantine and strict adherence with COVID-19 restrictions predicted increases in anxiety and worry symptoms (β = 0.07–0.11).Teleworking predicted a decrease in anxiety symptoms (β = −0.07) and higher age predicted a decrease in anxiety (β = −0.08) and worry symptoms (β = −0.10).
Conclusions
Our study showed neuroticism as a robust predictor of adverse changes in mental health, and identified additional sociodemographic and COVID-19-related predictors that explain longitudinal variability in mental health during the COVID-19 pandemic.