Bio-inspired band-gap tunable elastic optical multilayer fibers.

The concentrically-layered photonic structure found in the tropical fruit Margaritaria nobilis serves as inspiration for photonic fibers with mechanically tunable band-gap. The fibers show the spectral filtering capabilities of a planar Bragg stack while the microscopic curvature decreases the strong directional chromaticity associated with flat multilayers. Elongation of the elastic fibers results in a shift of the reflection of over 200 nm.Financial support from the US Air Force Offi ce of Scientifi c Research Multidisciplinary University Research Initiative under award numbers FA9550-09-1-0669-DOD35CAP, FA9550-10-1-0020 and the UK Engineering and Physical Sciences Research Council EP/G060649/1 is gratefully acknowledged. M.Ko. acknowledges the fi nancial support from the Alexander von Humboldt Foundation in form of a Feodor Lynen postdoctoral research fellowship. This work was performed in part at the Center for Nanoscale Systems (CNS), a member of the National Nanotechnology Infrastructure Network (NNIN), which is supported by the National Science Foundation under NSF award no. ECS-0335765. CNS is part of Harvard University

ElAM: A computer program for the analysis and representation of anisotropic elastic properties

Copyright © 2010 Elsevier. NOTICE: this is the author’s version of a work that was accepted for publication in Computer Physics Communications. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Computer Physics Communications, Volume 181, Issue 12 (2010), DOI: 10.1016/j.cpc.2010.08.033The continuum theory of elasticity has been used for more than a century and has applications in many fields of science and engineering. It is very robust, well understood and mathematically elegant. In the isotropic case elastic properties are easily represented, but for non-isotropic materials, even in the simple cubic symmetry, it can be difficult to visualise how properties such as Young's modulus or Poisson's ratio vary with stress/strain orientation. The ElAM (Elastic Anisotropy Measures) code carries out the required tensorial operations (inversion, rotation, diagonalisation) and creates 3D models of an elastic property's anisotropy. It can also produce 2D cuts in any given plane, compute averages following diverse schemes and query a database of elastic constants to support meta-analyses. Program summary Program title: ElAM1.0 Catalogue identifier: AEHB_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEHB_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 43 848 No. of bytes in distributed program, including test data, etc.: 2 498 882 Distribution format: tar.gz Programming language: Fortran90 Computer: Any Operating system: Linux, Windows (XP, Vista) RAM: Depends chiefly on the size of the arrays representing elastic properties in 3D Classification: 7.7 Nature of problem: Representation of elastic moduli and ratios, and of wave velocities, in 3D; automatic discovery of unusual elastic properties. Solution method: Stiffness matrix (6×6)(6×6) inversion and conversion to compliance tensor (3×3×3×3)(3×3×3×3), tensor rotation, dynamic matrix diagonalisation, simple optimisation, postscript and VRML output preparation. Running time: Dependent on angular accuracy and size of elastic constant database (from a few seconds to a few hours). The tests provided take from a few seconds for test0 to approximately 1 hour for test4

Structural colour from helicoidal cell-wall architecture in fruits of Margaritaria nobilis

The bright and intense blue-green coloration of the fruits of Margaritaria nobilis (Phyllanthaceae) was investigated using polarization-resolved spectroscopy and transmission electron microscopy. Optical measurements of freshly collected fruits revealed a strong circularly polarized reflection of the fruit that originates from a cellulose helicoidal cell wall structure in the pericarp cells. Hyperspectral microscopy was used to capture the iridescent effect at the single-cell level.This work was supported by the Leverhulme Trust (F/09- 741/G) and a BBSRC David Phillips fellowship (BB/K014617/1). P.V. acknowledges support from the US Air Force Office of Scientific Research under award number FA9550-10-1-0020. U.S. acknowledges support from the Adolphe Merkle foundation and the Swiss National Science Foundation through the National Centre of Competence in Research Bio-Inspired Materials

Brillouin scattering study on the single-crystal elastic properties of natrolite and analcime zeolites

Copyright © 2005 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Journal of Applied Physics 98 (2005) and may be found at http://link.aip.org/link/?jap/98/053508The Brillouin light-scattering technique was used to investigate the single-crystal elastic properties of two aluminosilicate zeolites, natrolite (NAT) and analcime (ANA), at ambient conditions. An inversion of the acoustic velocity data results in the full set of elastic stiffness moduli (Cij's) for both materials. From the single-crystal moduli the aggregate adiabatic bulk moduli (Ks), shear moduli (G), and Poisson's ratios (v) were found to be Ks=48.5(1.0) GPa, G=31.6(1.0) GPa, and v =0.232(5) for NAT, and Ks=59.8(1.2) GPa, G=32.1(1.0) GPa, and v=0.272(5) for ANA (Voigt-Reuss-Hill averages). The bulk and shear moduli of both zeolites are relatively low compared with those of densely packed aluminosilicates, reflecting an open framework structure of (Al,SiO4) tetrahedra which is easily deformed by bending the Si–O–Al angles. As expected for a less dense crystal, NAT is softer and more compressible than ANA. An evaluation of the directional Young's moduli shows that the compressibility of NAT is nearly uniform along the [100] and [010] axes, while [001] is stiffer, in agreement with previous compression studies. We do not find experimental evidence of negative Poisson's ratios for NAT zeolites as predicted by recent theoretical calculations

Leading for teacher learning

x, 106 leaves ; 28 cm. --Through their own unique learning styles, teachers constantly strive to improve their practice in order to meet the needs of their students as well as the ever increasing and changing demands for which they are responsible. An essential role of a school’s leadership is to actively support this learning to ensure the utmost success on behalf of the teachers and more importantly their students. This project endeavours to answer the following question in attempt to help school leaders better understand, and therefore respond to, the needs of their teachers: In what ways can educational leaders, such as principals and vice or assistant-principals support the professional learning of middle school teachers? In addition it explores teachers’ and leaders’ views on effective activities that are currently being used and those that could be used by educational leaders to most effectively support their individual professional learning. This exploration takes the form of semi-structured interviews with middle school teachers and principals. The results of the interviews are presented in a case-by-case format as well as a general thematic format of emerging trends from the data. These results are then compared to relevant previous research. The conclusion, which strongly advocates for the development of strong, personal relationships between teachers and school leaders, reports a review of the author’s suggested recommendations on how these relationships might be fostered and a summary of her own personal learning experience

Improving technology professional development

x, 97 leaves ; 29 cm. --The purpose of this project is to identify effective technology professional development practices and to provide direction for future professional development in the Holy Spirit School Division as it relates to integration of ICT Outcomes. Factors considered in identifying effectiveness of professional development activities included teachers' perceptions of: 1. appropriateness in content and applicability 2. relevance to their teaching assignment and their delivery of the Alberta ICT Outcomes 3. sustainability and support for review and further learning in the area An online survey was administered to teachers in the Holy Spirit School District during the spring of 2004. Five recommendations emerged based on the findings: 1. facilitate ongoing technology infused curriculum meetings, 2. develop and support District and school based leadership, 3. provide for a variety of technology professional development opportunities, 4. budget effectively for evergreening of technology, and 5. focus technology integration on the improvement of student learning

An examination into the use of the restorative justice model as an alternative to expulsion for extreme behaviour in schools

vi, 68 leaves ; 29 cm. --This study explores the use of the Community Conferencing Process, from The Restorative Justice Model, as a tool for school administrators to employ when dealing with students whose behaviour has been highly disruptive or dangerous. Traditionally, such students have been disciplined by excluding them through suspension or expulsion. This paper offers evidence from three case studies, in an urban setting, where the use of a conferencing approach resulted not only in the restoration of peace and safety within the school but also in significant learning for those involved in the incidents and for their families. Moreover, all students concerned were able to maintain their places in their school following the conference in which they participated. The key concepts of Community Conferencing are discussed, including the importance of perpetrators owning responsibility for their actions, the subsequent offering of meaningful restitution to those most affected, and the opportunities for healing created for all participants by the process. In the end, the Community Conferencing Process is seen not as a silver bullet but as a potentially useful additional strategy for administrators to include in their overall school discipline plan

Five teachers, five fingers, five narratives

vii, 128 leaves ; 29 cm. --This project will attempt to make pedagogical connections between aspects of contemporary autobiographical theory through teacher stories in the development of individual identity presented in an aesthetic and artistic manner. The project is about writing and sharing, making connections, building, and fostering our own identity as individuals. Comments throughout the project are included as they happened as a part of the overall process. It is not my intent to analyze or interpret each group member's ideas, but to share them as well as document how the process evolved. The goal was to allow all the participants, including myself, a medium to show how this process affected each of us and how we developed an identity. Five teachers, including myself, reflected on their teaching practice by writing narratives based on the five forms indicated by Preskill (1998) in Narratives of Teaching and the Quest for the Second Self). In this project, each teacher wrote one narrative based on one of the different forms highlighted in Preskill's article, which include narrative of social criticism, narrative of apprenticeship, narrative of reflective practice, narrative of journey, and narrative of hope. This project utilized a type of action research where participants were involved in reflecting, writing and sharing stories formed from teaching experiences. This sharing process aided in the recognition of identity and identity formation. My main objective was to allow each member to gain personal insights about her development as an individual and teacher. All members of the group were instrumental in offering each other support, reflection, and an arena to discuss the successes and failures in each other's career. Each member was an important contributor to the project and to the narratives of each person taking part in the project. The goal was to provide living action research about identity formation. I hope this project aided these teachers in a journey of identity exploration. This exploration allowed them to look at the influences in their lives as experiences they must embrace, write about, reflect upon, grow with and learn from as they continue to construct and reconstruct who they are as individuals, teachers, professionals, and women. Presentation of each member's narratives was also something that I wanted to develop, to allow for each member's uniqueness to become directly incorporated with their narrative. This was done through fmgerprints. Each member of the group chose a print from their left, or feminine, hand to transcribe their story into. This would allow each story to be unique to the individual, an expression of the person, the teacher, the woman. I felt that this was their own unique personal expression of their, and only their story. As the fingerprints are individual, so are the stories of the women of the group

The integration of literature and science : animal life cycles

viii, 75 leaves : ill. ; 29 cm. --This project concerns the integration ofliterature with the teaching of science. More specifically, it involves the foundational understanding, design, and delivery of an instructional unit in a grade three classroom in which literature was integrated to support the learning of scientific concepts concerning animal life cycles. In addition, it concerns the teacher's learning regarding the value of integration when she taught the Animal Life Cycle Unit from Topic E of the Alberta Program of Studies for Science. The project, as reported here, involves a limited study of the relevant research literature, a discussion of the advantages of integrating literature and science, a unit plan for the Animal Life Cycles Unit, and the teacher's reflections and recommendations. The research literature presents four themes: (a) increase in student achievement, concentrating on the implementation of the program and the ease in which the students understood the information; (b) improvement of students' attitudes and provision of background information, success provided the stimulus to further interest the students' studies; (c) selection and integration of high-quality literature, choosing a piece of literature that provides a link to the science curriculum; and (d) challenges integrating literature and science, highlighting the literature and need for further research in this area. Discussion of each includes examples from the teacher's classroom. The unit plan includes all lesson plans and lists of resources. All lessons draw upon and are adapted from literature sources. The blueprint of this unit includes objectives, resources, lesson plans, and assessment tools. In each lesson the scientific concepts are explored through literature and experimentation. Finally, the teacher's reflections include references to her learning as the instruction proceeded and her suggestions for how her teaching colleagues might facilitate integrated instruction. The majority of her suggestions concentrate on the organization of an integrated classroom. In brief, she concludes that the integration of literature and science enhances classroom learning, helping young students to make connections among concepts and to have the language needed to express their understanding