Self-Control of Traffic Lights and Vehicle Flows in Urban Road Networks

Based on fluid-dynamic and many-particle (car-following) simulations of traffic flows in (urban) networks, we study the problem of coordinating incompatible traffic flows at intersections. Inspired by the observation of self-organized oscillations of pedestrian flows at bottlenecks [D. Helbing and P. Moln\'ar, Phys. Eev. E 51 (1995) 4282--4286], we propose a self-organization approach to traffic light control. The problem can be treated as multi-agent problem with interactions between vehicles and traffic lights. Specifically, our approach assumes a priority-based control of traffic lights by the vehicle flows themselves, taking into account short-sighted anticipation of vehicle flows and platoons. The considered local interactions lead to emergent coordination patterns such as ``green waves'' and achieve an efficient, decentralized traffic light control. While the proposed self-control adapts flexibly to local flow conditions and often leads to non-cyclical switching patterns with changing service sequences of different traffic flows, an almost periodic service may evolve under certain conditions and suggests the existence of a spontaneous synchronization of traffic lights despite the varying delays due to variable vehicle queues and travel times. The self-organized traffic light control is based on an optimization and a stabilization rule, each of which performs poorly at high utilizations of the road network, while their proper combination reaches a superior performance. The result is a considerable reduction not only in the average travel times, but also of their variation. Similar control approaches could be applied to the coordination of logistic and production processes

Astrocytes: biology and pathology

Astrocytes are specialized glial cells that outnumber neurons by over fivefold. They contiguously tile the entire central nervous system (CNS) and exert many essential complex functions in the healthy CNS. Astrocytes respond to all forms of CNS insults through a process referred to as reactive astrogliosis, which has become a pathological hallmark of CNS structural lesions. Substantial progress has been made recently in determining functions and mechanisms of reactive astrogliosis and in identifying roles of astrocytes in CNS disorders and pathologies. A vast molecular arsenal at the disposal of reactive astrocytes is being defined. Transgenic mouse models are dissecting specific aspects of reactive astrocytosis and glial scar formation in vivo. Astrocyte involvement in specific clinicopathological entities is being defined. It is now clear that reactive astrogliosis is not a simple all-or-none phenomenon but is a finely gradated continuum of changes that occur in context-dependent manners regulated by specific signaling events. These changes range from reversible alterations in gene expression and cell hypertrophy with preservation of cellular domains and tissue structure, to long-lasting scar formation with rearrangement of tissue structure. Increasing evidence points towards the potential of reactive astrogliosis to play either primary or contributing roles in CNS disorders via loss of normal astrocyte functions or gain of abnormal effects. This article reviews (1) astrocyte functions in healthy CNS, (2) mechanisms and functions of reactive astrogliosis and glial scar formation, and (3) ways in which reactive astrocytes may cause or contribute to specific CNS disorders and lesions

The downward spiral of mental disorders and educational attainment: a systematic review on early school leaving.

BACKGROUND: Most psychiatric disorders present symptom patterns that cause severe impairment on the emotional, cognitive and social level. Thus, adolescents who suffer from a mental disorder risk finding themselves in a downward spiral caused by the reciprocal association of psychological symptoms and negative school experiences that may culminate in early school leaving. In addition to previous collective work that mainly focused on school refusing behaviour among children and was presented as an expert's opinion, the following systematic review fills the knowledge gap by providing a structured overview of the bidirectional association between mental health and secondary school dropout based on a sound methodology and with a particular focus on mediating factors. METHODS: Four electronic databases were searched from January 1990 until June 2014. Selected references were assessed for study details, main results, mediating factors and methodological limitations. Standardized risk of bias assessment was conducted. RESULTS: Mood and anxiety disorders seemed to have a less consequential direct effect on early school leaving than substance use and disruptive behaviour disorders. The association between externalizing disorders and educational attainment was even stronger when the disorder occurred early in life. On the other hand, internalizing disorders were reported to develop as a consequence of school dropout. Only few studies had addressed gender differences, with discrepant results. Socio-economic background, academic achievement and family support were identified as significant mediating factors of the association between mental disorders and subsequent educational attainment. CONCLUSIONS: Findings suggested a strong association between mental health and education, in both directions. However, most studies focused on mediating factors that could not be targeted by intervention programs

Effects of eight neuropsychiatric copy number variants on human brain structure

peer reviewedMany copy number variants (CNVs) confer risk for the same range of neurodevelopmental symptoms and psychiatric conditions including autism and schizophrenia. Yet, to date neuroimaging studies have typically been carried out one mutation at a time, showing that CNVs have large effects on brain anatomy. Here, we aimed to characterize and quantify the distinct brain morphometry effects and latent dimensions across 8 neuropsychiatric CNVs. We analyzed T1-weighted MRI data from clinically and non-clinically ascertained CNV carriers (deletion/duplication) at the 1q21.1 (n = 39/28), 16p11.2 (n = 87/78), 22q11.2 (n = 75/30), and 15q11.2 (n = 72/76) loci as well as 1296 non-carriers (controls). Case-control contrasts of all examined genomic loci demonstrated effects on brain anatomy, with deletions and duplications showing mirror effects at the global and regional levels. Although CNVs mainly showed distinct brain patterns, principal component analysis (PCA) loaded subsets of CNVs on two latent brain dimensions, which explained 32 and 29% of the variance of the 8 Cohen’s d maps. The cingulate gyrus, insula, supplementary motor cortex, and cerebellum were identified by PCA and multi-view pattern learning as top regions contributing to latent dimension shared across subsets of CNVs. The large proportion of distinct CNV effects on brain morphology may explain the small neuroimaging effect sizes reported in polygenic psychiatric conditions. Nevertheless, latent gene brain morphology dimensions will help subgroup the rapidly expanding landscape of neuropsychiatric variants and dissect the heterogeneity of idiopathic conditions. © 2021, The Author(s)

Effects of eight neuropsychiatric copy number variants on human brain structure

Many copy number variants (CNVs) confer risk for the same range of neurodevelopmental symptoms and psychiatric conditions including autism and schizophrenia. Yet, to date neuroimaging studies have typically been carried out one mutation at a time, showing that CNVs have large effects on brain anatomy. Here, we aimed to characterize and quantify the distinct brain morphometry effects and latent dimensions across 8 neuropsychiatric CNVs. We analyzed T1-weighted MRI data from clinically and non-clinically ascertained CNV carriers (deletion/duplication) at the 1q21.1 (n = 39/28), 16p11.2 (n = 87/78), 22q11.2 (n = 75/30), and 15q11.2 (n = 72/76) loci as well as 1296 non-carriers (controls). Case-control contrasts of all examined genomic loci demonstrated effects on brain anatomy, with deletions and duplications showing mirror effects at the global and regional levels. Although CNVs mainly showed distinct brain patterns, principal component analysis (PCA) loaded subsets of CNVs on two latent brain dimensions, which explained 32 and 29% of the variance of the 8 Cohen’s d maps. The cingulate gyrus, insula, supplementary motor cortex, and cerebellum were identified by PCA and multi-view pattern learning as top regions contributing to latent dimension shared across subsets of CNVs. The large proportion of distinct CNV effects on brain morphology may explain the small neuroimaging effect sizes reported in polygenic psychiatric conditions. Nevertheless, latent gene brain morphology dimensions will help subgroup the rapidly expanding landscape of neuropsychiatric variants and dissect the heterogeneity of idiopathic conditions

Working Paper Series Working Paper Series Working Paper Series Working Paper Series Academic Success and Struggle: A Study of Motivation and Literacy in a Sample of Low-Income 7th Graders Working Paper Series The Wellesley Centers for Women Ordering Infor

The Wellesley Centers for Women (WCW) conducts scholarly research and develops sound training and evaluation programs that place women's experiences at the center of its work. WCW focuses on three major areas: The status of women and girls and the advancement of their human rights both in the United States and around the globe; The education, care, and development of children and youth; and The emotional well-being of families and individuals. Issues of diversity and equity are central across all the work as are the experiences and perspectives of women from a variety of backgrounds and cultures. Since 1974, WCW has influenced public policy and programs by ensuring that its work reaches policy makers, practitioners, educators, and other agents of change. The Wellesley Centers for Women is the single organization formed in 1995 by combining the Center for Research on Women (founded 1974) and the Stone Center for Developmental Studies (founded 1981) at Wellesley College. For more information, please visit: www.wcwonline.org. Ordering Information Working Papers and other publications of the Wellesley Centers for Women (WCW) are available for purchase through the WCW Publications Office. For a complete list of current publications, visit our online catalog at: www.wcwonline.org/publications. In their review of the research on reading motivation, Guthrie and Knowles (2001) describe the tendency for researchers to view motivation as a goal-driven process in which the reader is either intrinsically or extrinsically motivated to read. Readers may seek to read because it is an end in itself, in the enjoyment it provides (Deci, 1992), or because it is a means to an end, such as grades, or rewards Intrinsic motivation has the potential to positively reinforce learning goals, in that the enjoyment and challenge of reading leads to mastery, which is an incentive to continue and expand reading practices. On the other hand, extrinsic motivation may lead to a reliance and undue focus on the reward at the expense of mastery Academic Success and Struggle Wellesley Centers for Women 4 strategies to understand text, tend to have better comprehension and achievement outcomes Much of the research on reading has not found significant gender differences for young readers (Snow, Barnes, & Griffin, 1998) and the same is true in our early findings from the Home-School Study. However, the literature does suggest gender differences with respect to special education identification, retention, and dropping out, with more boys being identified than girls (U.S. Department of Education. National Center for Education Statistics, 2000Statistics, , 2001. We found similar trends in the Home-School Study sample, as well as indications that girls' reading motivation tended to be intrinsic, while boys described being motivated for extrinsic reasons (Porche, Ross, & Snow, in press). Thus, we were particularly interested in examining gender differences related to motivation and achievement as students move through middle school. We hypothesize that cognitive ability, performance, engagement in school, academic self-esteem, and socio-economic status all contribute to achievement. Secondly, although there is little evidence of gender differences in the literature on early reading and language skills, we hypothesize that a difference does exist because boys and girls are socialized in and motivated towards language activities in different ways, such that girls are expected to do better in language arts and boys are expected to excel in math and science. Method Sample. This paper examines literacy motivation and success for a sample of racially and ethnically diverse low-income students (n=54) who have participated in a longitudinal study of literacy and language development since they were in preschool. To be included in the study, the families of these students had to qualify for Head Start services. Two-thirds of the children identified as White Teacher-Child Rating Scale (Hightower et al., 1986); T-CRS). English teachers completed the Teacher-Child Rating Scale (T-CRS) which was comprised of a series of questions about the student's learning habits (motivation to achieve, work habits and level of concentration, and ability to follow directions). Motivational Measures: Self-Perception Profile for Children Results Descriptive results. We investigate the relationship between motivation and language and literacy outcomes by first describing the range of motivation, reading, and demographic measures for this sample of students Clusters are ranked highest to lowest by the combination of reading achievement as measured by comprehension outcomes, and by ability, as measured by report card grades. Cluster Analysis. We used cluster analysis to discern groupings of students by the constellation of variables described above. This method allows us to distinguish among profiles of success or risk of failure in reading achievement and is used to distinguish groups of respondents rather than groups of variables. Each student had membership in one and only one profile type. The seven measurements used in the cluster analysis included reading comprehension ability (CAT), reported English grades, teacher ratings of student performance (T-CRS), scholastic competence (Harter), engagement (RAPS), future aspirations for higher education, and SES (represented by maternal education). This Academic Success and Struggle Wellesley Centers for Women 8 Although there were no significant differences among the clusters on measures of engagement, reported grades, future aspirations, and SES (ANOVAS were performed to test differences by cluster for each variable), we did find some significant differences in the areas of reading comprehension, teacher ratings, and selfperception of scholastic competence between the highest and lowest scoring clusters of students. We retained all seven of these measures in our cluster analysis for two reasons: 1) we felt that each variable does make a substantive difference, even if not apparent in a small sample, and 2) differences between groups on the constructs represented by these variables would be clearer in our qualitative analysis. Consider Clusters 1 and 2, representing students with high levels of reading comprehension and high reported grades. On average, students in Cluster 2 had the second highest score for reading comprehension, had the highest teacher ratings on performance and work habits, got the best grades, yet were the second highest in scholastic competence. In contrast, students in Cluster 1 scored highest in reading ability and highest in scholastic competence, on average, but had lower grades and lower teacher ratings. These very bright students, as reflected in standardized tests, were not performing to their potential and were viewed as average students by their teachers. While all students in Cluster 2 aspired to go to college, as a group, students in Cluster 1 were not as definite in their plans. This provides evidence that ability by itself is a necessary but not sufficient component of achievement. Cluster 5 represents students with low reading comprehension and poor grades. On average, these students have low opinions of themselves in the academic domain, and in fact scored the lowest on each of the seven measures. Many of these students were receiving support services at school (e.g., special education placement, Chapter I, counseling) and several reported a history of developmental delays due to premature birth or mother's substance abuse when pregnant. This cluster of students are at the highest risk of academic failure, and by 7th grade six had been retained one or more times. Overall, students in Clusters 3 and 4 appear to be average or slightly above average in reading comprehension and grades compared to other students in the sample. Compared to Cluster 3, Cluster 4 students have lower comprehension ability, on average, yet are doing slightly better in their grades and received more positive ratings by their teachers. The Cluster 4 students appear to be putting out more effort in school, for their ability level, compared to Cluster 3, where students appear to be working below their abilities. Writing Task: Quantitative Analysis We first reviewed students' writing task samples using typical language skill assessments, before moving on to a more psychological analysis of students' narratives. Scores on the writing ability measures -Form, Content, and Total Score -were for the most part normally distributed across the sample with a slight skew towards the higher end Thematic analysis. Essays were content-coded for theme in the following areas: types of jobs specified, references to college, references to where they would be living, and references to romantic relationships and/or children. Within these descriptions we differentiated between fantasy-based narratives and more realistic narratives. For these thematic groups we examined gender differences present in the students' essays. Thematic analysis of the writing samples offers insight into the importance these adolescents place on different aspects of their future, such as gaining employment, continuing their education, and engaging in meaningful romantic relationships, as well as the degree to which they (and their parents) have begun to plan for their future. By content coding the writing samples Writing Task Qualitative Analysis While we did not find motivation to be a significant differentiator of groups in our cluster analysis, we nevertheless believe that motivation, as measured by student engagement, is in fact a critical component of literacy success. To explore this further, we examined evidence of motivation within the students' writing samples and interview narratives, using both a thematic and interpretive analysis. These qualitative analyses provided some clues to differences between clusters that were not captured in our standardized measures of motivation and writing

Synchronous/Asynchronous Approaches for Intelligent Real-Time Systems

This paper describes a system called SATURNE (Synchronous AnyTime coUpling for Real-time reasoNing dEsign), which constitutes a framework for designing intelligent time critical systems. The model involves a mixed (synchronous/asynchronous) programming approach built around a strong synchronous formalism for the expression of critical timing constraints, and conventional asynchronous languages for the expression of the transformational parts. The major originality of the SATURNE approach consists in introducing an anytime model of computation for meeting temporal deadlines. This work is supported by the French Ministry of Defense (DRET)