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The thermodynamics and transport properties of polymeric materials are essential for the design of reactors and for the development of polymer deconstruction processes. Existing property prediction tools such as correlations based on entropy scaling, kinetic gas theory, and free-volume model are inadequate for polymers. In this paper, we introduce a data-driven model for polyolefins based on data from molecular dynamics simulations that can accurately predict the transport properties of polyethylenes and their binary mixtures with higher n-alkanes across a range of temperatures, pressures, concentrations, and oligomer molecular weights.

There is considerable interest in designing new polymeric materials with built-in mechanisms for recycling. In this work, we present a systematic exploration of several polyethylene-based polymers that contain strategically incorporated cleavable bonds that are susceptible to chemical degradation. We consider ten distinct telechelic functionalities across varying chain lengths: ester, aromatic ester, anhydride, carbonate, urethane, siloxane, oxalate, acetal, urea, and amide linkages. Our study is focused on the effects of cleavable bonds on density, diffusion, enthalpy, and melting temperatures. We also examine the crystallization process. These are key properties for polymer processing and, by comparing them to those of linear polyethylene, we establish a platform that will help guide future synthetic efforts towards the design of sustainable plastics with performance comparable to that of traditional, high-performance polyolefin-based materials.

The center stage of neuro-imaging is currently occupied by studies of functional correlations between brain regions. These correlations define the brain functional networks, which are the most frequently used framework to represent and interpret a variety of experimental findings. In previous work we first demonstrated that the relatively stronger BOLD activations contain most of the information relevant to understand functional connectivity and subsequent work confirmed that a large compression of the original signals can be obtained without significant loss of information. In this work we revisit the correlation properties of these epochs to define a measure of nonlinear dynamic directed functional connectivity (nldFC) across regions of interest. We show that the proposed metric provides at once, without extensive numerical complications, directed information of the functional correlations, as well as a measure of temporal lags across regions, overall offering a different perspective in the analysis of brain co-activation patterns. In this paper we provide for a proof of concept, based on replicating and completing existing results on an Autism database, to discuss the main features and advantages of the proposed strategy for the study of brain functional correlations. These results show new interpretations of the correlations found on this sample., Comment: 12 pages, 8 figures

The Collaborative Schools for Innovation and Success (CSIS) pilot program was a partnership that paired colleges of education with low-performing, high-poverty elementary schools. The purpose of the five-year pilot was to increase student achievement, close the opportunity gap, and change the way teacher candidates learn to teach students in selected schools. The CSIS project has allowed selected elementary schools to implement research-based, innovative practices with their college of education partners. At the same time, the colleges of education were able to improve their teacher education programs. Strong university and school district partnerships were developed over the course of the project and are set to continue beyond the end of CSIS funding. To conclude the work of this pilot project (Revised Code of Washington [RCW] 28A.630.107), the Office of Superintendent of Public Instruction (OSPI) and the Professional Educator Standards Board (PESB) recommend the pilot project be continued and expanded into a grant for other school district and college of education partnerships in the state. In addition, both OSPI and PESB also recommend the pilot project be expanded into a grant to include middle and high schools in the state.

This paper reports on findings from a research project aimed at examining teachers' change over time (the first 2 years of teaching) through their own perceptions, the perceptions of their students, and analyses of the school culture in which they work. Overall, a general pattern was found: most teachers developed according to a narrow, individual and classroom-oriented perspective, which was accompanied by a shift from a more inductive and student-centered approach to teaching towards a more traditional one. However, it was found that four teachers did develop and change in positive ways over time. Personal biography, namely prior experiences as students and student teachers, the influence of former teachers and relatives, and images of self-as-learner associated with perceptions of school culture and leadership, explaining both similarities and differences amongst teachers. Implications of the findings for understanding the (trans)formation of teacher identity, teacher socialization, and the role of schools in the continuing professional development of teachers are discussed. (Contains 58 references.) (Author/SM)

This study examined findings from a larger study that investigated how a cohort of 14 new teachers learned and developed over the first 2 years of teaching. Data collection involved interviews, questionnaires, and reports. Findings suggested an idiosyncratic, practical, and context-specific conception of learning. Respondents undervalued the formal contexts of learning, such as preservice education and field experiences, and they highlighted the strong influence of workplace norms and values on the process of (re)learning in practice. Results noted the powerful effect of students' reactions within the classroom, day-to-day experience at school, and significant others (relatives and former teachers) on teacher learning in the workplace. Certain perceptions of school culture and leadership impacted the ways in which new teachers learned and developed over time. A narrow understanding of teacher professional development prevailed. They saw learning more as an individual and lonely business than a joint venture. Teachers emphasized that they learned alone, from their mistakes, and by analyzing their students' reactions within the classroom. (Contains 56 references.) (SM)

This paper presents and discusses findings from a European project concerning strengthening the teacher's voice in defining professional quality. In the project tools were developed and evaluated to help teachers reflect on their professional quality. Twelve countries participated and twelve tools were tested with help of student teachers, teachers, teacher educators, school leaders and policy makers. Evaluations were completed by the tool testers and the test leaders through questionnaires and, in the case of the tool designers, through reflective journals on their experiences. Findings showed that the tool design was a success in aiding professional development via discussion about teacher quality amongst the participants. Even though the result was mainly positive, findings also showed that the tools can be further developed. Overall, the findings demonstrate that there are other ways of encouraging teachers to consider what constitutes good quality in teaching rather than imposing external standards.