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Two-level quantum systems, qubits, are not the only basis for quantum computation. Advantages exist in using qudits, d-level quantum systems, as the basic carrier of quantum information. We show that color codes, a class of topological quantum codes with remarkable transversality properties, can be generalized to the qudit paradigm. In recent developments it was found that in three spatial dimensions a qubit color code can support a transversal non-Clifford gate, and that in higher spatial dimensions additional non-Clifford gates can be found, saturating Bravyi and K\"onig's bound [Phys. Rev. Lett. 110, 170503 (2013)]. Furthermore, by using gauge fixing techniques, an effective set of Clifford gates can be achieved, removing the need for state distillation. We show that the qudit color code can support the qudit analogues of these gates, and show that in higher spatial dimensions a color code can support a phase gate from higher levels of the Clifford hierarchy which can be proven to saturate Bravyi and K\"onig's bound in all but a finite number of special cases. The methodology used is a generalisation of Bravyi and Haah's method of triorthogonal matrices [Phys. Rev. A 86 052329 (2012)], which may be of independent interest. For completeness, we show explicitly that the qudit color codes generalize to gauge color codes, and share the many of the favorable properties of their qubit counterparts., Comment: Authors' final copy

The surface code is one of the most promising candidates for combating errors in large scale fault-tolerant quantum computation. A fault-tolerant decoder is a vital part of the error correction process---it is the algorithm which computes the operations needed to correct or compensate for the errors according to the measured syndrome, even when the measurement itself is error prone. Previously decoders based on minimum-weight perfect matching have been studied. However, these are not immediately generalizable from qubit to qudit codes. In this work, we develop a fault-tolerant decoder for the surface code, capable of efficient operation for qubits and qudits of any dimension, generalizing the decoder first introduced by Bravyi and Haah [Phys. Rev. Lett. 111, 200501 (2013)]. We study its performance when both the physical qudits and the syndromes measurements are subject to generalized uncorrelated bit-flip noise (and the higher dimensional equivalent). We show that, with appropriate enhancements to the decoder and a high enough qudit dimension, a threshold at an error rate of more than 8% can be achieved., Comment: 13 pages, 19 figures, authors' final copy

To date, a great deal of attention has focused on characterizing the performance of quantum error correcting codes via their thresholds, the maximum correctable physical error rate for a given noise model and decoding strategy. Practical quantum computers will necessarily operate below these thresholds meaning that other performance indicators become important. In this work we consider the scaling of the logical error rate of the toric code and demonstrate how, in turn, this may be used to calculate a key performance indicator. We use a perfect matching decoding algorithm to find the scaling of the logical error rate and find two distinct operating regimes. The first regime admits a universal scaling analysis due to a mapping to a statistical physics model. The second regime characterizes the behavior in the limit of small physical error rate and can be understood by counting the error configurations leading to the failure of the decoder. We present a conjecture for the ranges of validity of these two regimes and use them to quantify the overhead -- the total number of physical qubits required to perform error correction., Comment: 12 pages, 12 figures

This brief is a summary of "Increasing the Application of Developmental Sciences Knowledge in Educator Preparation: Policy Issues and Recommendations" by Robert C. Pianta, Randy Hitz and Blake West. It includes highlights and policy recommendations contained in that paper. This brief argues that teachers and education administrators need access to developmental Sciences knowledge--specifically about child and adolescent development--in order to make the most of students' abilities to engage with and benefit from the new policy reforms. In addition, it is believed that if teacher education is to be a relevant factor in coming education reform, a far better job of incorporating the developmental sciences knowledge into the fabric of programs and the process of teacher licensing must be done. This brief also lays out evidence that indicates there is currently no consistent, systemic, or programmatic linkage between the developmental sciences and educator preparation and describes the issues and barriers that must be overcome to create the necessary linkages. The report "Increasing the Application of Developmental Sciences Knowledge in Educator Preparation: Policy Issues and Recommendations" (ED550462) and this brief end with concrete recommendations for how developmental sciences knowledge can be integrated into federal and state policy, educator preparation programs, and accreditation practices--for the benefit of our children, our schools, and our society.

Recently, in an effort to improve the education and subsequent life opportunities of our nation's children, 48 states have committed to use newly developed, common national academic standards and possibly institute some common measures for assessing student learning related to these standards. This is an impressive undertaking. However, research over the past decade indicates that this effort is more likely to be successful if it is grounded more deeply in the science and principles of the developmental sciences. A recent report by the National Institute for Child Health and Human Development (NICHD) says "current research points to the fact that aspects of development--neural, cognitive, social, psychological, physical and ethical--have far-reaching effects on children's ability to learn." In other words, educators need access to scientifically based knowledge about how students develop and learn in order to improve students' ability to engage with and learn from the curriculum. But many educators--teachers and administrators--have not been prepared to understand and apply developmental sciences knowledge in their classrooms and schools. This brief focuses on how professional education programs can help educators acquire and apply knowledge about child and adolescent development to support all the students in their care. Following a vignette that illustrates effective application of child developmental principles, the authors (1) identify some of the general areas of child and adolescent development and learning that will assist educators in helping students achieve their goals and become productive citizens; (2) discuss how educator preparation programs can be designed to help PreK-12 educators use this knowledge to create successful classroom and school environments; and (3) provide examples of how child and adolescent development science and principles are being integrated into actual educator preparation programs. They conclude with policy recommendations for how educator preparation programs and accrediting bodies can advance teacher knowledge and application of child and adolescent development. This brief is a summary of "Principles and Exemplars for Integrating Developmental Sciences Knowledge into Educator Preparation" (ED550392). It includes highlights and policy recommendations contained in that paper.

The most important problem facing public education in the country today is: how can teachers address the needs of all learners? A 2007 report issued by the National Institute of Child Health and Human Development (NICHD) says, "aspects of development--neural, cognitive, social, psychological, physical and ethical--have far-reaching effects on children's ability to learn." In other words, if teachers are to address the increasingly diverse needs of all of the children that are entering today's classrooms, they need access to scientifically-based knowledge concerning student development and learning. Many educators, however--both teachers and administrators--have not been prepared to understand and apply advances in the developmental sciences in their schools and classrooms. To address this issue, in 2007, the National Council for Accreditation of Teacher Education (NCATE) convened a national expert panel to develop recommendations for strategies to increase application of the developmental sciences in educator preparation. As part of this effort, NCATE commissioned two papers designed to bring attention to this critical need: (1) "Principles and Exemplars for Integrating Developmental Sciences Knowledge into Educator Preparation" (ED550392); and (2) "Increasing the Application of Developmental Sciences Knowledge in Educator Preparation: Policy Issues and Recommendations" (ED550462). This report summarizes the key points from the commissioned papers and contains the expert panel's recommendations for key stakeholders. A summary is as follows: (1) Educator preparation programs should ensure that candidates possess contemporary knowledge of child and adolescent development and understand its effective application in the PreK-12 classroom; (2) Accrediting bodies should adopt standards for educator preparation programs that incorporate specific evidence of candidates' mastery of the core competencies associated with knowledge of child and adolescent development; (3) States should ensure that the knowledge base of child/adolescent development is integrated into all routes to teaching; and (4) When relevant, explicit use of "knowledge and application of the contemporary developmental sciences knowledge" should be added to review criteria for U.S. Department of Education grant programs, particularly those that pertain to educator preparation and evaluation and to school turn-around. A list of selected references from the two commissioned papers is included.

We analyze several high dimensional generalizations of the toric code at nonzero temperature. We find that in large enough dimension, there can be a distinct separation between the critical temperature $T_c$, given by thermodynamic singularities, and the percolation temperature $T_p$, given by the percolation of defects. We argue that the regime $T_p

This report summarizes key implementation lessons from the six-city Community Change for Youth Development (CCYD) initiative, which investigated whether providing neighborhoods a framework of ideas (core concepts) would speed the process and increase the effectiveness of neighborhood-wide, resident-involvement initiatives aimed at assisting all youths residing in those neighborhoods. The core concepts were: adult support and guidance; gap activities; work as a developmental tool (work/learning); youth involvement in decision making; and support through transitions. Data collected from the sites led to the development of 10 lessons, including that it is possible to implement and sustain a neighborhood-wide youth development initiative, based on a common substantive framework, in resource-poor neighborhoods; research-based core concepts are extremely useful; variation and flexibility in the roles residents play, and commitment to clarifying and supporting those roles, are essential to integrating residents into such initiatives; older youth and high-risk youth are more difficult to attract to positive youth development initiatives and require targeted outreach; large-scale initiatives need a structured approach to assessing program quality on an ongoing basis; and place-based initiatives cannot draw a fence around a neighborhood. An appendix presents CCYD lead agency and sits descriptions. (SM)

Kansas City, Missouri, is one of six sites in a national demonstration project, Community Change for Youth Development (CCYD), which aims to increase basic developmental supports and opportunities available to youth age 12-20 years. The demonstration focuses on five basic elements: adult support and guidance, opportunities for involvement in decision making, support through critical transitions, opportunities for using work as a developmental tool, and provision of positive activities after school, in the evenings, on weekends, and during the summer. The lead agency is the YMCA of Greater Kansas City, a traditional youth-serving organization. Because of its considerable organizational capacity, the YMCA was successful in operating the CCYD initiative, quickly implementing activities and expanding to additional neighborhoods. The YMCA faced two challenges in implementing CCYD. Implementing the work as a developmental tool core concept proved difficult, and involving adult residents in the management and other aspects of CCYD programming, a key element of the initiative, also proved difficult. The YMCA of Greater Kansas City demonstrated that with commitment and the proper technical assistance, a traditional youth-serving agency can successfully lead a youth-focused, community-change effort that involves local citizens in oversight and in shaping program offerings. (SM)

This report describes the Philadelphia Youth Aid Panel (YAP), an alternative approach to juvenile justice. YAPs, also known as Community Accountability Panels, evolved from 1950s legislation empowering panels of community members to handle low-level juvenile offenders. The Youth Aid Panel allows low-level juvenile offenders who have admitted their guilt to avoid facing the criminal justice system. YAP operates through the District Attorney's Office and is open to youthful first-time, nonviolent offenders. Juveniles and their parents go before a panel of community members, and sentences are passed that includes: restitution, serious self-reflection, and community service. Youths are assigned to monitors who maintain contact throughout the process. Section 1 describes YAP and its operations, based on information from interviews and focus groups with youths, panelists, parents, police officers, probation officers, and YAP staff. Section 2 analyzes data on 300 1994 YAP youth tracked through the juvenile and adult court record systems. Another 300 similar youth, arrested for low-level crimes in 1994 but not part of YAP, were also tracked. This provided a context for examining YAP recidivism rates. Overall, most YAP participants were male, black youth age 14-17 years who committed weapons violations. Over 70 percent of participants completed the program. Within 3 years, 29.9 percent of YAP completers were rearrested, compared with 44.4 percent of non-YAP youth. Section 3 discusses promising aspects of YAP, offering recommendations on strengthening operations and future research. (SM)

This paper looks systematically at the experiences of two demonstration projects, Plain Talk and Community Change for Youth Development (CCYD), and discusses their attempts to implement resident involvement strategies. Chapter 1 is an introduction. Chapter 2 provides a brief overview of the two demonstration projects that indicates all sites in both projects experienced similar developmental phases in relation to resident involvement as they moved from planning to start-up to fuller implementation, although the projects differ in their goals and scope. Chapter 3 examines the following: the roles residents played during the planning phase and their relationships with site staff; how and why these roles and relationships changed and became a great deal more challenging and uncertain during initial program implementation; the strategies that sites used to overcome these challenges; and the range of roles that residents adopted as implementation progressed. The last chapter offers lessons from the Plain Talk and CCYD experiences and explores implications of these lessons for practitioners, program designers, and policymakers. (YLB)

Research has shown that three main barriers impede the ability of inner-city, low-income job seekers to find employment in the suburbs: an administrative or information barrier, a physical barrier, and a social barrier. The Bridges to Work demonstration program was designed to test the idea that improved access to suburban jobs can significantly improve outcomes for low-income urban workers and their neighborhoods. The elements of the Bridges to Work model are designed to address each of the three barriers described. Bridges elements include the following: (1) a placement mechanism across the metropolitan area to connect residents of inner-city neighborhoods to suburban job openings; (2) a targeted commute to allow residents to reach those suburban destinations; and (3) limited support services aimed at mitigating problems created or exacerbated by the daily commute to distant and unfamiliar job locations. Following 2 years of planning, 5 sites--in Baltimore, Chicago, Denver, Milwaukee, and St. Louis--began 4 years of project operations in late 1996. The sites are designed to answer questions about the strategy, policy, concerns and funding shifts. At present, the five sites are grappling with immediate concerns: (1) administrative barriers among the agencies and jurisdictions involved; (2) physical barriers involving transportation providers; and (3) social barriers, including racism and lack of supportive services. (KC)