Local and global responses to disaster: #eqnz and the Christchurch earthquake

Building on innovative frameworks for analysing and visualising the tweet data available from Twitter, developed by the authors, this paper examines the patterns of tweeting activity that occurred during and after the Feb, 2011 Christchurch earthquake. Local and global responses to the disaster were organised around the pre-existing hashtag #eqnz, which averaged some 100 tweets per minute in the hours following the earthquake. The paper identifies the key contributors to the #eqnz network and shows the key themes of their messages. Emerging from this analysis is a more detailed understanding of Twitter and other social media as key elements in the overall ecology of the media forms used for crisis communication. Such uses point both to the importance of social media as a tool for affected communities to self-organise their disaster response and recovery activities, and as a tool for emergency management services to disseminate key information and receive updates from local communities.

Porous scaffold architecture guides tissue formation

Critical-sized bone defect regeneration is a remaining clinical concern. Numerous scaffold-based strategies are currently being investigated to enable in vivo bone defect healing. However, a deeper understanding of how a scaffold influences the tissue formation process and how this compares to endogenous bone formation or to regular fracture healing is missing. It is hypothesized that the porous scaffold architecture can serve as a guiding substrate to enable the formation of a structured fibrous network as a prerequirement for later bone formation. An ovine, tibial, 30-mm critical-sized defect is used as a model system to better understand the effect of the scaffold architecture on cell organization, fibrous tissue, and mineralized tissue formation mechanisms in vivo. Tissue regeneration patterns within two geometrically distinct macroscopic regions of a specific scaffold design, the scaffold wall and the endosteal cavity, are compared with tissue formation in an empty defect (negative control) and with cortical bone (positive control). Histology, backscattered electron imaging, scanning small-angle X-ray scattering, and nanoindentation are used to assess the morphology of fibrous and mineralized tissue, to measure the average mineral particle thickness and the degree of alignment, and to map the local elastic indentation modulus. The scaffold proves to function as a guiding substrate to the tissue formation process. It enables the arrangement of a structured fibrous tissue across the entire defect, which acts as a secondary supporting network for cells. Mineralization can then initiate along the fibrous network, resulting in bone ingrowth into a critical-sized defect, although not in complete bridging of the defect. The fibrous network morphology, which in turn is guided by the scaffold architecture, influences the microstructure of the newly formed bone. These results allow a deeper understanding of the mode of mineral tissue formation and the way this is influenced by the scaffold architecture. Copyright © 2012 American Society for Bone and Mineral Research.

Teachers’ work in curricular markets : conditions of design and relations between the International Baccalaureate Diploma and the local curriculum

School level strategy enabled by neoliberal choice policies can produce internal curricular markets whereby branded curricula such as the International Baccalaureate are offered alongside the local government curriculum in the same school. This project investigated how such curricular markets operating in Australian schools impacted on teachers’ work. This paper reports on teachers work in three case study schools that offered both the International Baccalaureate Diploma program and the local senior schooling curriculum, then draws on an online survey of 225 teachers in 26 such schools across Australia. The analysis reveals the impact of curricular markets along two dimensions: the curriculum’s internal design; and the relational aspects of how schools manage to deliver tandem offerings within institutional constraints. Teachers working in the IBD Diploma program were shown to relish its design, despite additional demands, while teachers working in just the local curriculum reported more relational issues. The paper argues that these trends suggest that there are winners and losers emerging in the work conditions produced by curricular markets.  

Hessian-based affine adaptation of salient local image features

Affine covariant local image features are a powerful tool for many applications, including matching and calibrating wide baseline images. Local feature extractors that use a saliency map to locate features require adaptation processes in order to extract affine covariant features. The most effective extractors make use of the second moment matrix (SMM) to iteratively estimate the affine shape of local image regions. This paper shows that the Hessian matrix can be used to estimate local affine shape in a similar fashion to the SMM. The Hessian matrix requires significantly less computation effort than the SMM, allowing more efficient affine adaptation. Experimental results indicate that using the Hessian matrix in conjunction with a feature extractor that selects features in regions with high second order gradients delivers equivalent quality correspondences in less than 17% of the processing time, compared to the same extractor using the SMM.

Vibrational spectroscopic study of the mineral creaseyite Cu2Pb2(Fe,Al)2(Si5O17)·6H2O – a zeolite mineral?

Vibrational spectroscopy has been used to characterise the mineral creaseyite Cu2Pb2(Fe,Al)2(Si5O17)·6H2O. The mineral is found in the oxidised zone of base metal deposits and interestingly is associated with copper silicate minerals including ajoite, kinoite, chrysocolla as well as wulfenite, willemite, mimetite and wickenburgite. Creaseyite is a mineral with zeolitic properties. A Raman band at 998 cm−1 is assigned to the SiO stretching vibration of SiO3 units. The Raman band at 1071 cm−1 is assigned to the SiO stretching vibrations of the Si2O5 units. Raman bands are found at 2750, 2902, 3162, 3470 and 3525 cm−1. The band at 3525 cm−1 is attributed to zeolitic water. Other bands are assigned to water coordinated to the metal cations. Vibrational spectroscopy enables aspects of the molecular structure of creaseyite to be determined.

Vibrational spectroscopic study of the minerals cavansite and pentagonite Ca(V4+O)Si4O10.4H2O

The bright blue minerals cavansite and pentagonite, a calcium vanadium silicate Ca(V4+O)Si4O10.4H2O, have been studied by UV–Visible, Raman and infrared spectroscopy. Cavansite shows an open porous structure with very small micron sized holes. Strong UV–Visible absorption bands are observed at around 403, 614 and 789 nm for cavansite and pentagonite. The Raman spectrum of cavansite is dominated by an intense band at 981 cm -1 and pentagonite by a band at 971 cm-1 attributed to the stretching vibrations of (SiO3)n units. Cavansite is characterised by two intense bands at 574 and 672 cm-1 whereas pentagonite by a single band at 651 cm-1. The Raman spectrum of cavansite in the hydroxyl stretching region shows bands at 3504, 3546, 3577, 3604 and 3654 cm-1 whereas pentagonite is a single band at 3532 cm_1. These bands are attributed to water coordinated to calcium and vanadium. XPS studies show that bond energy of oxygen in oxides is 530 eV, and in hydroxides -531.5 eV and for water -533.5 eV. XPS studies show a strong peak at 531.5 eV for cavansite, indicating some OH units in the structure of cavansite.

Prediction of pull-out force of multi-walled carbon nanotube (MWCNT) in sword-in-sheath mode

The pull-out force of some outer walls against other inner walls in multi-walled carbon nanotubes (MWCNTs) was systematically studied by molecular mechanics simulations. The obtained results reveal that the pull-out force is proportional to the square of the diameter of the immediate outer wall on the sliding interface, which highlights the primary contribution of the capped section of MWCNT to the pull-out force. A simple empirical formula was proposed based on the numerical results to predict the pull-out force for an arbitrary pull-out in a given MWCNT directly from the diameter of the immediate outer wall on the sliding interface. Moreover, tensile tests for MWCNTs with and without acid-treatment were performed with a nanomanipulator inside a vacuum chamber of a scanning electron microscope (SEM) to validate the present empirical formula. It was found that the theoretical pull-out forces agree with the present and some previous experimental results very well.

Coupling of energy from quantum emitters to the plasmonic mode of V groove waveguides: A numerical study

This work is a theoretical investigation into the coupling of a single excited quantum emitter to the plasmon mode of a V groove waveguide. The V groove waveguide consists of a triangular channel milled in gold and the emitter is modeled as a dipole emitter, and could represent a quantum dot, nitrogen vacancy in diamond, or similar. In this work the dependence of coupling efficiency of emitter to plasmon mode is determined for various geometrical parameters of the emitter-waveguide system. Using the finite element method, the effect on coupling efficiency of the emitter position and orientation, groove angle, groove depth, and tip radius, is studied in detail. We demonstrate that all parameters, with the exception of groove depth, have a significant impact on the attainable coupling efficiency. Understanding the effect of various geometrical parameters on the coupling between emitters and the plasmonic mode of the waveguide is essential for the design and optimization of quantum dot–V groove devices.

Creating Institutions: Linking the Local and the Global in the Travel of Crime Policies

Institutions represent the ‘technologies of the social.’ They are increasingly modelled and transported to other cultures and societies, and criminal justice institutions—traditional, parochial, and local as they are—are no exception to this. Problems of crime and insecurity have engendered the travelling of institutions from the centre to the periphery and vice versa. This paper will explore the problems which arise from travelling and modelling, and from the transport and creation of institutions in the area of criminal justice. An important feature in the travel of criminal justice institutions is the use of ‘local knowledge’ and its role in this process.

White Lines: The Intercultural Politics of Everyday Movement in Local Spaces

This article draws on research into racist vilification experienced by young Arab and Muslim Australians especially since 11 September 2001, to explore the links between public space, movement and national belonging, and the spatial regulation of cultural difference that functions in Australia. The authors analyse the way that the capacity to experience forms of national belonging and cultural citizenship is shaped by inclusion within or exclusion from local as well as nationally significant public spaces. While access to public space and freedom to move are conventionally seen as fundamental to a democratic state, these are often seen in abstract terms. This article emphasises how movement in public space is a very concrete dimension of our experience of freedom, in showing how incivilities directed against Arab and Muslim Australians have operated pedagogically as a spatialised regulation of national belonging. The article concludes by examining how processes associated with the Cronulla riots of December 2005 have retarded the capacities of Muslim and Arab Australians to negotiate within and across spaces, diminishing their opportunities to invest in local and national spaces, shrinking their resources and opportunities for place-making in public space.

School Leadership, Literacy and Social Justice : The Place of Local School Curriculum Planning and Reform

School reform is a matter of both redistributive social justice and recognitive social justice. Following Fraser (Justice interruptus: critical reflections on the “postsocialist” condition. Routledge, New York, 1997), we begin from a philosophical and political commitment to the more equitable redistribution of knowledge, credentials, competence, and capacity to children of low socioeconomic, cultural, and linguistic minority and Indigenous communities whose access, achievement, and participation historically have “lagged” behind system norms and benchmarks set by middle class and dominant culture communities. At the same time, we argue that the recognition of these students and their communities’ lifeworlds, knowledges, and experiences in the curriculum, in classroom teaching, and learning is both a means and an end: a means toward improved achievement measured conventionally and a goal for reform and alteration of mainstream curriculum knowledge and what is made to count in the school as valued cultural knowledge and practice. The work that we report here was based on an ongoing 4-year project where a team of university teacher educators/researchers have partnered with school leadership and staff to build relationships within community. The purpose has been to study whether and how engagement with new digital arts and multimodal literacies could have effects on students “conventional” print literacy achievement and, secondly, to study whether and how the overall performance of a school could be generated through a focus on professional conversations and partnerships in curriculum and instruction – rather than the top-down implementation of a predetermined pedagogical scheme, package, or approach.

Molecular structure of the mineral svanbergite SrAl3(PO 4,SO4)2(OH)6 - A vibrational spectroscopic study

The mineral svanbergite SrAl 3(PO 4,SO 4) 2(OH) 6 is a hydroxy phosphate-sulphate mineral belonging to the beudantite subgroup of alunites and has been characterised by vibrational spectroscopy. Bands at various wavenumbers were assigned to the different vibrational modes of svanbergite, which were then associated with the structure of the mineral. Bands were primarily assigned to phosphate and sulphate stretching and bending modes. Two symmetric stretching modes for both phosphate and sulphate supported the concept of non-equivalent phosphate and sulphate units in the mineral structure. Bands in the OH stretching region enabled hydrogen bond distances to be calculated. Comparison of the hydrogen bond distances and the calculated hydrogen bond distances from the structure models indicates that hydrogen bonding in svanbergite occurs between the two OH units rather than OH to SO42- units.