3,112 research outputs found

    Topological modular forms with level structure

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    The cohomology theory known as Tmf, for "topological modular forms," is a universal object mapping out to elliptic cohomology theories, and its coefficient ring is closely connected to the classical ring of modular forms. We extend this to a functorial family of objects corresponding to elliptic curves with level structure and modular forms on them. Along the way, we produce a natural way to restrict to the cusps, providing multiplicative maps from Tmf with level structure to forms of K-theory. In particular, this allows us to construct a connective spectrum tmf_0(3) consistent with properties suggested by Mahowald and Rezk. This is accomplished using the machinery of logarithmic structures. We construct a sheaf of locally even-periodic elliptic cohomology theories, equipped with highly structured multiplication, on the log-\'etale site of the moduli of elliptic curves. Evaluating this sheaf on modular curves produces Tmf with level structure.Comment: 53 pages. Heavily revised, including the addition of a new section on background tools from homotopy theor

    The spectra ko and ku are not Thom spectra: an approach using THH

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    We apply an announced result of Blumberg-Cohen-Schlichtkrull to reprove (under restricted hypotheses) a theorem of Mahowald: the connective real and complex K-theory spectra are not Thom spectra.Comment: 9 pages, 7 figure

    Does State Policy Help or Hurt the Dropout Problem in California?

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    Examines the scope and causes of California's dropout problem, and assesses whether some state policies unintentionally drive students out of schools. Proposes a comprehensive policy framework focused on effectively serving at-risk students

    Local error estimates for adaptive simulation of the Reaction-Diffusion Master Equation via operator splitting

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    The efficiency of exact simulation methods for the reaction-diffusion master equation (RDME) is severely limited by the large number of diffusion events if the mesh is fine or if diffusion constants are large. Furthermore, inherent properties of exact kinetic-Monte Carlo simulation methods limit the efficiency of parallel implementations. Several approximate and hybrid methods have appeared that enable more efficient simulation of the RDME. A common feature to most of them is that they rely on splitting the system into its reaction and diffusion parts and updating them sequentially over a discrete timestep. This use of operator splitting enables more efficient simulation but it comes at the price of a temporal discretization error that depends on the size of the timestep. So far, existing methods have not attempted to estimate or control this error in a systematic manner. This makes the solvers hard to use for practitioners since they must guess an appropriate timestep. It also makes the solvers potentially less efficient than if the timesteps are adapted to control the error. Here, we derive estimates of the local error and propose a strategy to adaptively select the timestep when the RDME is simulated via a first order operator splitting. While the strategy is general and applicable to a wide range of approximate and hybrid methods, we exemplify it here by extending a previously published approximate method, the Diffusive Finite-State Projection (DFSP) method, to incorporate temporal adaptivity

    Venturing into schools : locating mental health initiatives in complex environments

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    Schools provide viable settings for mental health promotion initiatives, such as programs to develop students’ social and emotional capabilities (SEC). Complexity in the school environments into which initiatives are introduced, such as diverse student capabilities, school structures, and teachers’ knowledge and confidence, will play an integral role in the success of those initiatives. This paper investigates the environments of schools about to receive the KidsMatter mental heath promotion, prevention and early intervention initiative in Australia, using information sourced from questionnaires about 2598 students and their teachers in 50 Australian primary schools. The focus of the report is on the status of the schools’ work in one of the key focus areas for the intervention, namely students’ SEC. Analysis showed relatively high levels of students’ SEC across the whole sample, but with sub-group differences. Teachers’ attitudes towards SEC learning were highly positive. Teachers’ self-rated knowledge and approaches in dealing with SEC were moderate, and point to requirements for additional pre-service and professional development. The extent of regular and sustained delivery of SEC programs and mental health initiatives in general showed variability, suggesting the need to attend to school systems and structural supports. Implications of these areas of diversity in school environments on the selection and methods of delivery of mental health promotion programs in schools are discussed.peer-reviewe

    First detection of a low-mass stellar halo around the young open cluster Eta Chamaeleontis

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    We have identified several lithium-rich low-mass (0.08<M<0.3 Msun) stars within 5.5 deg of the young open cluster Eta Chamaeleontis, nearly four times the radius of previous search efforts. Of these stars we propose 4 new probable cluster members, and 3 possible members requiring further investigation. These findings are consistent with a dynamical origin for the current configuration of the cluster, without the need to invoke an abnormal Initial Mass Function deficient in low-mass objects. Candidates were selected on the basis of DENIS and 2MASS photometry, NOMAD astrometry and extensive follow-up spectroscopy.Comment: 5 Pages. 5 Figures and 1 Table. Accepted for publication in MNRAS Letters. Higher resolution figures available at http://www.mso.anu.edu.au/~murphysj/

    An Innovative Collective Parent Engagement Model for Families and Neighborhoods in Arrival Cities

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    Arrival Cities are special urban places. Amid the largest migration in human history, they provide homes for large numbers of mobile, low-income, immigrant families. These families need new human service and child welfare service models. Collective parent engagement (CPE) is one such model. CPE is designed to build on the strengths and meet the needs of immigrant families living in Arrival City neighborhoods. In contrast to interventions focused on individual parents, this CPE model mobilizes groups of parents; and with a dual agenda. CPE develops much-needed “anchoring supports” for mobile, vulnerable families, at the same time that it positions local organizations to become welcoming, supportive, and resource-providing social settings for families on the move. Enhanced professional preparation and training programs, together with enhanced organizational and policy development, are needed to realize this important agenda

    The Effectiveness of a Primary School Based Badminton Intervention on Children’s Fundamental Movement Skills

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    This study examined the effects of the Badminton World Federation (BWF) Shuttle Time program on fundamental movement skills (FMS) in English children. A total of 124 children; 66 in key stage 1 (ages 6&ndash;7 years) and 58 in key stage 2 (10&ndash;11 years) undertook the Shuttle Time program, once weekly for six weeks (n = 63) or acted as controls (n = 61). Pre, post and ten-weeks post, both process and product FMS were determined. Children in the intervention group, aged 6&ndash;7 years, had higher total process FMS (via test of gross motor development-2) compared to the control group at post and ten-weeks post intervention (both p = 0.0001, d = 0.6 and 0.7, respectively). There were no significant differences in process FMS scores for children aged 10&ndash;11 years. Ten-meter sprint speed decreased pre to post and was maintained at ten-weeks post for the intervention groups aged 6&ndash;7 years (p = 0.0001, d = 0.6) and 10&ndash;11 years (p = 0.001, d = 0.2) compared to control. Standing long jump distance increased pre to post (p = 0.0001, d = 0.8) and was maintained at ten-weeks post (p = 0.0001, d = 0.5) for the intervention group. Medicine ball throw performance increased pre to post (p = 0.0001, d = 0.3) for the intervention group. The BWF Shuttle Time program is beneficial in developing FMS for key stage 1 children (ages 6&ndash;7)
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