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The primary objective of this study is to develop teaching materials for chemical engineering students (or students pursuing other related B.Sc./M.Sc. degrees) that encourage self-learning to facilitate understanding and the development of problem-solving skills. Tools are oriented to support the teaching of “Introduction to Chemical Engineering” courses to 1st year B.Sc. students in Chemical Engineering, 2nd year B.Sc. students in Chemistry, and 3rd year B.Sc. students in Biochemistry at the Universidad Complutense de Madrid (UCM). Problem generators of standard exercises, as an additional complement to the exercises that are used in the lectures, seminars, and assignments to facilitate the learning of the students, have been developed. These generators provide exercises to students with “unlimited” initial values (with certain restrictions). The software that was used to develop these materials was Jupyter Notebook, which runs under the Python 3.6 language. The problem generators can be classified into fixed problem generators, case-based generators, and random problem generators. Additionally, lecturing tools have been developed to support teaching using live/interactive examples. These examples can learning understanding of various topics of the courses.

Sleep is an important contributor for neural maturation and emotion regulation during adolescence, with long-term effects on a range of white matter tracts implicated in affective processing in at-risk populations. We investigated the effects of adolescent sleep patterns on longitudinal changes in white matter development and whether this is related to the emergence of emotional (internalizing) problems. Sleep patterns and internalizing problems were assessed using self-report questionnaires in adolescents recruited in the general population followed up from age 14-19 years (N = 111 White matter structure was measured using diffusion tensor imaging (DTI) and estimated using fractional anisotropy (FA). We found that longitudinal increases in time in bed (TIB) on weekends and increases in TIB-variability between weekdays to weekend, were associated with an increase in FA in various interhemispheric and cortico-striatal tracts. Extracted FA values from left superior longitudinal fasciculus mediated the relationship between increases in TIB on weekends and a decrease in internalizing problems. These results imply that while insufficient sleep might have potentially harmful effects on long-term white matter development and internalizing problems, longer sleep duration on weekends (catch-up sleep) might be a natural counteractive and protective strategy.

This study analyzes the journal impact factor and related bibliometric indicators in Education and Educational Research (E&ER) category, highlighting the main differences among journal quartiles, using Web of Science (Social Sciences Citation Index, SSCI) as the data source. High impact journals (Q1) publish only slightly more papers than expected, which is different to other areas. The papers published in Q1 journal have greater average citations and lower uncitedness rates compared to other quartiles, although the differences among quartiles are lower than in other areas. The impact factor is only weakly negative correlated (r=-0.184) with the journal self-citation but strongly correlated with the citedness of the median journal paper (r= 0.864). Although this strong correlation exists, the impact factor is still far to be the perfect indicator for expected citations of a paper due to the high skewness of the citations distribution. This skewness was moderately correlated with the citations received by the most cited paper of the journal (r= 0.649) and the number of papers published by the journal (r= 0.484), but no important differences by journal quartiles were observed. In the period 2013–2018, the average journal impact factor in the E&ER has increased largely from 0.908 to 1.638, which is justified by the field growth but also by the increase in international collaboration and the share of papers published in open access. Despite their inherent limitations, the use of impact factors and related indicators is a starting point for introducing the use of bibliometric tools for objective and consistent assessment of researcher.

It is unclear whether deviations in brain and behavioral development, which may underpin elevated substance use during adolescence, are predispositions for or consequences of substance use initiation. Here, we examine behavioral and neuroimaging indices at early and mid-adolescence in drug-naive youths to identify possible predisposing factors for substance use initiation and its possible consequences.Among 304 drug-naive adolescents at baseline (age 14 years) from the IMAGEN dataset, 83 stayed drug-naive, 133 used alcohol on 1 to 9 occasions, 42 on 10 to 19 occasions, 27 on 20 to 39 occasions, and 19 on40 occasions at follow-up (age 16 years). Baseline measures included brain activation during the Monetary Incentive Delay task. Data at both baseline and follow-up included measures of trait impulsivity and delay discounting.From baseline to follow-up, impulsivity decreased in the 0 and 1- to 9-occasions groups (p .004), did not change in the 10- to 19-occasions and 20- to 29-occasions groups (p.294), and uncharacteristically increased in the40-occasions group (p = .046). Furthermore, blunted medial orbitofrontal cortex activation during reward outcome at baseline significantly predicted higher alcohol use frequency at follow-up, above and beyond behavioral and clinical variables (p = .008).These results suggest that the transition from no use to frequent drinking in early to mid-adolescence may disrupt normative developmental changes in behavioral control. In addition, blunted activity of the medial orbitofrontal cortex during reward outcome may underscore a predisposition toward the development of more severe alcohol use in adolescents. This distinction is clinically important, as it informs early intervention efforts in preventing the onset of substance use disorder in adolescents.

Objective Irritable mood, a common and impairing symptom in psychopathology, has been proposed to underlie the developmental link between oppositional problems in youth and depression in adulthood. We examined the neural correlates of adolescent irritability in IMAGEN, a sample of 2,024 14-year-old adolescents from 5 European countries. Method The Development and Well-Being Assessment (DAWBA) was used to assess attention-deficit/hyperactivity disorder, major depressive disorder, oppositional defiant disorder, and generalized anxiety disorder. Three items from the DAWBA, selected as close matches to the Affective Reactivity Index, were used to assess irritability. Structural magnetic resonance imaging was examined using whole-brain voxel-based morphometry analysis, and functional magnetic resonance imaging was examined during a stop signal task of inhibitory control. Imaging data were included in structural equation models to examine the direct and indirect associations between irritable mood and comorbid DSM diagnoses. Results Whole-brain voxelwise analysis showed that adolescent irritable mood was associated with less gray matter volume and less neural activation underlying inhibitory control in frontal and temporal cortical areas (cluster-correction at p Conclusion This study identifies adolescent irritability as an independent construct and points to a neurobiological correlate to irritability that is an important contributing feature to many psychopathological disorders.

This study aims to provide information about the Q Concept defined as the division of journal impact factors into quartiles based on given field categories so that the disadvantages resulting from the direct use of journal impact factors can be eliminated. While the number of "Original articles published in the Web of Science (WoS) database-indexed journals like SCI, SSCI and A&HCI" is an important indicator for research assessment in Turkey, neither the journal impact factors nor the Q Concept of these papers have been taken into account. Present study analyzes the scientific production of the Amasya University researchers in journals indexed in WoS database in the period 2014-2018 using the Q concept. The share of publications by Q category journals as well as the average citations received by the works from Amasya University were compared to the average situation in Turkey and other different countries in the world. Results indicate that the articles published by Amasya University researchers were mostly published in low impact factor journals (Q4 journals) (36.49%), in fact, only a small share of papers were published in high impact journals (14.32% in Q1 journals). The share of papers published in low impact journals by researchers from Amasya University is higher than the Turkish average and much higher than the scientific leading countries. The average citations received by papers published in Q1 journals was around six times higher than papers published in Q4 journals (8.92 vs. 1.56), thus papers published in Q1 journals received 30.02% citations despite only 14.32% of the papers was published in these journals. The share of papers published which were never cited in WoS was 27.48%, increasing from 9.68% in Q1 to almost half (48.10%) in Q4. The study concludes with some suggestions on how and where the Q Concept can be used.

Les technologies de l’information et de la communication ont profondément marqué le champ de la santé. De nouvelles pratiques médicales utilisant ces technologies tentent de promouvoir une meilleure égalité d’accès aux soins, en particulier dans le champ de la santé mentale et des addictions où le recours aux professionnels de santé demeure faible. L’addiction aux jeux de hasard et d’argent en ligne, que nous désignerons sous le terme de jeu problématique, semble représenter un modèle pertinent de mesures de prévention et de soin fondé sur l’exploitation des données numériques issues du Big data et sur l’utilisation des nouvelles technologies. Ens effet, les données issues des comptes des joueurs offrent la possibilité d’une lecture directe de leur comportement de jeu. Parallèlement, le recours à l’internet offre un cadre de soin auquel les joueurs en ligne pourraient être particulièrement sensibles.

IntroductionDevelopment of fully internet-based programs could provide a new avenue to improve access to healthcare for problem gamblers. In this project, we aim to assess the efficacy of a web-based cognitive intervention targeting inhibitory control among problem gamblers, using a randomised controlled design. As impaired inhibitory control is involved in self-regulation difficulties in behavioural addictions, it represents a particularly relevant cognitive process to target for an online psychological intervention.Methods and analysisThis will be a single-blinded, randomised, comparative therapeutic web-based, controlled trial. Up to 200 non-treatment seeking adult problem gamblers with a Problem Gambling Severity Index-recent (PGSI-recent) score ≥5 will be included. The intervention will be a computerised cognitive training program targeting inhibitory skills. The comparator, an active control, will be a computerised neutral sensorial program. Both programs will be carried out under similar conditions: biweekly online training for 6 weeks and optional telephone support will be offered to patients for debriefing. The main objective of the study is to assess the clinical efficacy of the online cognitive training program at 6 weeks, measured with the PGSI-recent. The secondary objectives are to assess the efficacy on the gambling behaviour assessed by the account-based gambling data, on the self-reported gambling practice, and on the inhibition performance at the neuropsychological level at 6, 14 and 52 weeks. We will also assess the acceptability of this program and the preferred level of guidance. Data analysis will be in intention-to-treat.Ethics and disseminationThis randomized controlled trial will be executed in compliance with the Helsinki Declaration, and was approved by the local ethics boards (Comité de Protection des Personnes) in October 2017. The findings will be published in peer-reviewed journals.Trial registration numberNCT03673800.

Objective: White matter microstructure alterations have recently been associated with depressive episodes during adolescence, but it is unknown whether they predate depression. The authors investigated whether subthreshold depression in adolescence is associated with white matter microstructure variations and whether they relate to depression outcome. Method: Adolescents with subthreshold depression (N=96) and healthy control subjects (N=336) drawn from a community-based cohort were compared using diffusion tensor imaging and whole brain tract-based spatial statistics (TBSS) at age 14 to assess white matter microstructure. They were followed up at age 16 to assess depression. Probabilistic tractography was used to reconstruct white matter streamlines spreading from the regions identified in the TBSS analysis and along bundles implicated in emotion regulation, the uncinate fasciculus and the cingulum. The authors searched for mediating effects of white matter microstructure on the relationship between baseline subthreshold depression and depression at follow-up, and then explored the specificity of the findings. Results: Lower fractional anisotropy (FA) and higher radial diffusivity were found in the anterior corpus callosum in the adolescents with subthreshold depression. Tractography analysis showed that they also had lower FA in the right cingulum streamlines, along with lower FA and higher mean diffusivity in tracts connecting the corpus callosum to the anterior cingulate cortex. The relation between subthreshold depression at baseline and depression at follow-up was mediated by FA values in the latter tracts, and lower FA values in those tracts distinctively predicted higher individual risk for depression. Conclusions: Early FA variations in tracts projecting from the corpus callosum to the anterior cingulate cortex may denote a higher risk of transition to depression in adolescents.

Review papers tend to be cited more frequently than regular research articles. This fact, together with the continuous increase of the share of reviews in scientific literature, can have important consequences for the measurement of individuals’ research output, usually based on citation analysis. However, studies evaluating the differences in citations of review papers compared to original research articles are almost non-existing in the literature. This paper presents a thorough analysis of the overcitation and overrepresentation of review papers in the most cited papers of the 35 largest subject categories in Science Citation Index-Expanded. Results indicate the average citations received by reviews depends largely on the research area considered, varying from 1.34 to 6.74 times the citations received by original research articles (average value is 2.95). Correlated with this overcitation, there is an important overrepresentation of reviews in the most cited papers, this overrepresentation being greater when the most highly cited papers are considered, i.e. 0.05% and 0.1% most cited papers, where the share of reviews have increased from 16 to 18% in 1990 to around 40% in 2010. Interestingly, the overcitation and overrepresentation in the most cited papers is more important in the areas with the lowest shares of reviews in total publications.

The main objective of this study is to optimize a two-step treatment for mature landfill leachate consisting of electrocoagulation (EC) followed by Fenton or UVA-LED photo-Fenton processes aiming to provide a more efficient and feasible alternative treatment strategy that also increases biodegradability and decreases conductivity. Although 5 mA cm−2 EC is cheaper than 10 mA cm−2 EC per kg of removed COD (0.63 vs. 0.89 € kgCOD−1), it achieved the half total COD removal (13% compared to 26%), and the low residual iron concentration (100 mg L−1) that remained at the end of the process made necessary a long treatment time to perform the posterior Fenton (48 h) or UVA-LED photo-Fenton (6 h) process. When EC was performed at 10 mA cm−2, the residual iron concentration (220 mg L−1) was high enough to reduce treatment time by one half for both Fenton processes. Consequently, treatment cost decreases from 5.91 to 3.48 € kgCOD−1 for the EC + UVA-LED photo-Fenton ([H2O2]/COD = 1.063) treatment combination; whereas it slightly decreases from 1.68 to 1.61 € kgCOD−1 for the alternative EC + conventional Fenton combination. In both cases, total COD removal was around 87%. In addition, SUVA removal was >40%, conductivity was reduced about 20–30%, and biodegradability (BOD5/COD) increased over 0.3.

Effluent reuse is a common practice for sustainable industrial water use. Salt removal is usually carried out by a combination of membrane processes with a final reverse osmosis (RO). However, the presence of silica limits the RO efficiency due to its high scaling potential and the difficulty of cleaning the fouled membranes. Silica adsorption has many advantages compared to coagulation and precipitation at high pHs: pH adjustment is not necessary, the conductivity of treated waters is not increased, and there is no sludge generation. Therefore, this study investigates the feasibility of using pseudoboehmite and its calcination product (γ-Al2O3) for silica adsorption from a paper mill effluent. The effect of sorbent dosage, pH, and temperature, including both equilibrium and kinetics studies, were studied. γ-Al2O3 was clearly more efficient than pseudoboehmite, with optimal dosages around 2.5–5 g/L vs. 7.5–15 g/L. The optimum pH is around 8.5–10, which fits well with the initial pH of the effluent. The kinetics of silica adsorption is fast, especially at high dosages and temperatures: 80–90% of the removable silica is removed in 1 h. At these conditions, silica removal is around 75–85% (&lt, 50 mg/L SiO2 in the treated water).

Adolescence is a critical period for circadian rhythm, with a strong shift toward eveningness around age 14. Also, eveningness in adolescence has been found to predict later onset of depressive symptoms. However, no previous study has investigated structural variations associated with chronotype in early adolescence and how this adds to the development of depressive symptoms.Assessment of 128 community-based adolescents (51% girls) at age 14 and 19 years was performed. Using whole-brain voxel-based morphometry, baseline (at age 14) regional gray matter volumes (GMVs), follow-up (at age 19) regional GMVs, and longitudinal changes (between 14 and 19) associated with Morningness/Eveningness Scale in Children score and sleep habits at baseline were measured. The association of GMV with depressive symptoms at 19 years was studied, and the role of potential clinical and genetic factors as mediators and moderators was assessed.Higher eveningness was associated with larger GMV in the right medial prefrontal cortex at ages 14 and 19 in the whole sample. GMV in this region related to depressive symptoms at age 19 in catechol-O-methyltransferase (COMT) Val/Val, but not in Met COMT, carriers. Larger GMV also was observed in the right fusiform gyrus at age 14, which was explained by later wake-up time during weekends.In adolescence, eveningness and its related sleep habits correlated with distinct developmental patterns. Eveningness was specifically associated with GMV changes in the medial prefrontal cortex; this could serve as a brain vulnerability factor for later self-reported depressive symptoms in COMT Val/Val carriers.

Though adolescence is a time of emerging sex differences in emotions, sex-related differences in the anatomy of the maturing brain has been under-explored over this period. The aim of this study was to investigate whether puberty and sexual differentiation in brain maturation could explain emotional differences between girls and boys during adolescence. We adapted a dedicated longitudinal pipeline to process structural and diffusion images from 335 typically developing adolescents between 14 and 16 years. We used voxel-based and Regions of Interest approaches to explore sex and puberty effects on brain and behavioral changes during adolescence. Sexual differences in brain maturation were characterized by amygdala and hippocampal volume increase in boys and decrease in girls. These changes were mediating the sexual differences in positive emotional regulation as illustrated by positive attributes increase in boys and decrease in girls. Moreover, the differential maturation rates between the limbic system and the prefrontal cortex highlighted the delayed maturation in boys compared to girls. This is the first study to show the sex effects on the differential cortico/subcortical maturation rates and the interaction between sex and puberty in the limbic system maturation related to positive attributes, reported as being protective from emotional disorders.

BACKGROUND: The orbitofrontal cortex (OFC) is implicated in depression. The hypothesis investigated was whether the OFC sensitivity to reward and nonreward is related to the severity of depressive symptoms.METHODS: Activations in the monetary incentive delay task were measured in the IMAGEN cohort at ages 14 years (n = 1877) and 19 years (n = 1140) with a longitudinal design. Clinically relevant subgroups were compared at ages 19 (high-severity group: n = 116; low-severity group: n = 206) and 14.RESULTS: The medial OFC exhibited graded activation increases to reward, and the lateral OFC had graded activation increases to nonreward. In this general population, the medial and lateral OFC activations were associated with concurrent depressive symptoms at both ages 14 and 19 years. In a stratified high-severity depressive symptom group versus control group comparison, the lateral OFC showed greater sensitivity for the magnitudes of activations related to nonreward in the high-severity group at age 19 (p = .027), and the medial OFC showed decreased sensitivity to the reward magnitudes in the high-severity group at both ages 14 (p = .002) and 19 (p = .002). In a longitudinal design, there was greater sensitivity to nonreward of the lateral OFC at age 14 for those who exhibited high depressive symptom severity later at age 19 (p = .003).CONCLUSIONS: Activations in the lateral OFC relate to sensitivity to not winning, were associated with high depressive symptom scores, and at age 14 predicted the depressive symptoms at ages 16 and 19. Activations in the medial OFC were related to sensitivity to winning, and reduced reward sensitivity was associated with concurrent high depressive symptom scores.

International audience; Objective: Cannabis consumption during adolescence has been reported as a risk factor for psychotic-like experiences (PLEs) and schizophrenia. However, brain developmental processes associated with cannabis-related PLEs are still poorly described.Method: A total of 706 adolescents from the general population who were recruited by the IMAGEN consortium had structural magnetic resonance imaging scans at both 14 and 19 years of age. We used deformation-based morphometry to map voxelwise brain changes between the two time points, using the pairwise algorithm in SPM12b. We used an a priori region-of-interest approach focusing on the hippocampus/parahippocampus to perform voxelwise linear regressions. Lifetime cannabis consumption was assessed using the European School Survey Project on Alcohol and other Drugs (ESPAD), and PLEs were assessed with the Comprehensive Assessment Psychotic-like experiences (CAPE) tool. We first tested whether hippocampus/parahippocampus development was associated with PLEs. Then we formulated and tested an a priori simple mediation model in which uncus development mediates the association between lifetime cannabis consumption and PLEs.Results: We found that PLEs were associated with reduced expansion within a specific region of the right hippocampus/parahippocampus formation, the uncus (p = .002 at the cluster level, p = .018 at the peak level). The partial simple mediation model revealed a significant total effect from lifetime cannabis consumption to PLEs (b = 0.069, 95% CI = 0.04−0.1, p =2 × 10−16), as well as a small yet significant, indirect effect of right uncus development (0.004; 95% CI = 0.0004−0.01, p = .026).Conclusion: We show here that the uncus development is involved in the cerebral basis of PLEs in a population-based sample of healthy adolescents

Information and communication numeric technologies now have a deep influence on the field of healthcare. New medical practices using these technologies attempt to promote greater equality in the access of healthcare services, particularly in the field of mental health and addictions where the use of care remains low. Online gambling addiction, which we will here refer to problem gambling, seems to represent a relevant model of prevention and care measures based on the use of digital data extracted from Big data and the use of new technologies. The data from player accounts offer the possibility of a direct assessment of their gaming behavior. At the same time, we assume that the use of the Internet provides a framework for care to which online players may be particularly sensitive.La santé à l’ère du numérique - Apports du Big data et des nouvelles technologies dans la prévention et le traitement de l’addiction aux jeux d’argent en ligne.Les technologies de l’information et de la communication ont profondément marqué le champ de la santé. De nouvelles pratiques médicales utilisant ces technologies tentent de promouvoir une meilleure égalité d’accès aux soins, en particulier dans le champ de la santé mentale et des addictions où le recours aux professionnels de santé demeure faible. L’addiction aux jeux de hasard et d’argent en ligne, que nous désignerons sous le terme de jeu problématique, semble représenter un modèle pertinent de mesures de prévention et de soin fondé sur l’exploitation des données numériques issues du Big data et sur l’utilisation des nouvelles technologies. Ens effet, les données issues des comptes des joueurs offrent la possibilité d’une lecture directe de leur comportement de jeu. Parallèlement, le recours à l’internet offre un cadre de soin auquel les joueurs en ligne pourraient être particulièrement sensibles.

Laboratories are commonly included as part of university courses as a way to relate theoretical lectures with experimental processes. In this sense, an excellent tool widely employed in academic teaching is the use of simulation software as a link between theory and traditional hands-on practice. This work is focused on the use of a virtual lab, i.e., a simulation, to study the electrolysis of water for hydrogen production, as a complement to traditional hands-on labs to help students comprehend the basics of this industrial process. At Complutense University of Madrid, students perform this laboratory as part of an engineering course included in the program of the chemical engineering bachelor’s degree during their junior year. First, in this work, the hands-on lab is described as one of the cases proposed. Three more cases involving the virtual lab are also included as part of the laboratory experience. The last proposed case is focused on the theoretical background that students should have acquired during the hands-on and virtual lab sessions: three questions have to be addressed by the students. This work also includes a section where the opinions of students, their feedback after performing the labs, and the opinions of their professors (the authors) are incorporated to finally report some ideas for future work and conclusions about the ongoing teaching experience. A peculiarity of the use of virtual labs is that, in this case, they are performed after the hands-on labs, and therefore, they do not aim to prepare students for the laboratory by presenting the necessary theory for the experiment. The motivation of this virtual lab is to provide students with knowledge of the physical/chemical phenomena that govern the electrolysis process through the use of a theoretical model in order to reduce the limitations of the hands-on labs, such as the operating conditions, i.e., time, temperature, and number of cells, and to provide them with values for the parameters of a real system that can help with a critical discussion of the measured results.

Negative life events (NLE) contribute to anxiety and depression disorders, but their relationship with brain functioning in adolescence has rarely been studied. We hypothesized that neural response to social threat would relate to NLE in the frontal–limbic emotional regions. Participants (N = 685) were drawn from the Imagen database of 14-year-old community adolescents recruited in schools. They underwent functional MRI while viewing angry and neutral faces, as a probe to neural response to social threat. Lifetime NLEs were assessed using the ‘distress’, ‘family’ and ‘accident’ subscales from a life event dimensional questionnaire. Relationships between NLE subscale scores and neural response were investigated. Links of NLE subscales scores with anxiety or depression outcomes at the age of 16 years were also investigated. Lifetime ‘distress’ positively correlated with ventral-lateral orbitofrontal and temporal cortex activations during angry face processing. ‘Distress’ scores correlated with the probabilities of meeting criteria for Generalized Anxiety Disorder or Major Depressive Disorder at the age of 16 years. Lifetime ‘family’ and ‘accident’ scores did not relate with neural response or follow-up conditions, however. Thus, different types of NLEs differentially predicted neural responses to threat during adolescence, and differentially predicted a de novo internalizing condition 2 years later. The deleterious effect of self-referential NLEs is suggested.

Heavy drinker adolescents: altered brainstem microstructure.The cortical-cerebellar circuit is vulnerable to heavy drinking (HD) in adults. We hypothesized early microstructural modifications of the pons/midbrain region, containing core structures of the reward system, in HD adolescents. Thirty-two otherwise symptom-free HDs at age 14 (HD14) and 24 abstainers becoming HDs at age 16 (HD16) were identified in the community with the Alcohol Use Disorders Identification Test (AUDIT) and compared with abstainers. The monetary incentive delay (MID) task assessed reward-sensitive performance. Voxelwise statistics of diffusion tensor imaging (DTI) values in the thalamo-ponto-mesencephalic region were obtained using tract-based spatial statistics. Projections between the ventral tegmental area (VTA) and the nucleus accumbens (NAcc) were identified by probabilistic tractography. Lower fraction of anisotropy and higher radial diffusivity (RD) values were detected in the upper dorsal pons of HD14 adolescents, and a trend for higher RD in HD16, compared with abstainers. When expecting reward, HD14 had higher MID task success scores than abstainers, and success scores were higher with a lower number of tracts in all adolescents. In symptom-free community adolescents, a region of lower white matter (WM) integrity in the pons at age 14 was associated with current HD and predicted HD at age 16. HD was related to reward sensitivity.

Summary Changing sleep rhythms in adolescents often lead to sleep deficits and increased variability in sleep schedules. The adolescent brain, and in particular the rapidly developing structures involved in emotional control, are vulnerable to external and internal factors. In our previous study in adolescents at age 14, we observed a strong relationship between weekend sleep schedules and regional medial prefrontal cortex grey matter volumes. Here, we aimed to assess whether this relationship remained in this group of adolescents of the general population at the age of 16 (n=101; mean age 16.8 years; 55% girls). We further examined grey matter volumes in the hippocampi and the amygdalae, calculated with voxel-based morphometry. In addition, we investigated the relationship between regional grey matter volumes with psychological functioning. Sleep was assessed with self-reports and psychological functioning with the Strengths and Difficulties Questionnaire and tests on working memory and impulsivity. Later weekend wake-up times were associated with smaller grey matter volumes in the medial prefrontal cortex and the amygdalae, and greater weekend delays in wake-up time were associated with smaller grey matter volumes in the right hippocampus and amygdala. The medial prefrontal cortex region mediated the correlation between weekend wake up time and both externalising and internalising symptoms. Paying attention to regular sleep habits during adolescence could act as a protective factor against the emergence of psychopathology via enabling favourable brain development. Abbreviations Anatomical Automatic Labeling (AAL); Alcohol Use Disorders Identification Test (AUDIT); Cambridge Automated Neuropsychological Test Battery (CANTAB); Family Wise Error (FWE); Magnetisation Prepared Rapid Acquisition Gradient Echo (MPRAGE); Medial Prefrontal Cortex (mPFC); Montreal Neurologic Institute (MNI); functional Magnetic Resonance Imaging (fMRI); Region Of Interest (ROI); Statistical Parametric Mapping (SPM); Strengths and Difficulties Questionnaire (SDQ); Voxel-Based Morphometry (VBM); Weekday (WD); Weekend (WE)

This study examines the effects of puberty and sex on the intrinsic functional connectivity (iFC) of brain networks, with a focus on the default-mode network (DMN). Consistently implicated in depressive disorders, the DMN’s function may interact with puberty and sex in the development of these disorders, whose onsets peak in adolescence, and which show strong sex disproportionality (females > males). The main question concerns how the DMN evolves with puberty as a function of sex. These effects are expected to involve within- and between-network iFC, particularly, the salience and the central-executive networks, consistent with the Triple-Network Model. Resting-state scans of an adolescent community sample (n = 304, male/female: 157/147; mean/std age: 14.6/0.41 years), from the IMAGEN database, were analyzed using the AFNI software suite and a data reduction strategy for the effects of puberty and sex. Three midline regions (medial prefrontal, pregenual anterior cingulate, and posterior cingulate), within the DMN and consistently implicated in mood disorders, were selected as seeds. Within- and between-network clusters of the DMN iFC changed with pubertal maturation differently in boys and girls (puberty-X-sex). Specifically, pubertal maturation predicted weaker iFC in girls and stronger iFC in boys. Finally, iFC was stronger in boys than girls independently of puberty. Brain–behavior associations indicated that lower connectivity of the anterior cingulate seed predicted higher internalizing symptoms at 2-year follow-up. In conclusion, weaker iFC of the anterior DMN may signal disconnections among circuits supporting mood regulation, conferring risk for internalizing disorders.