Temporal tracking of mineralization and transcriptional developments of shell formation during the early life history of pearl oyster Pinctada maxima

Molluscan larval ontogeny is a highly conserved process comprising three principal developmental stages. A characteristic unique to each of these stages is shell design, termed prodissoconch I, prodissoconch II and dissoconch. These shells vary in morphology, mineralogy and microstructure. The discrete temporal transitions in shell biomineralization between these larval stages are utilized in this study to investigate transcriptional involvement in several distinct biomineralization events. Scanning electron microscopy and X-ray diffraction analysis of P. maxima larvae and juveniles collected throughout post-embryonic ontogenesis, document the mineralogy and microstructure of each shelled stage as well as establishing a timeline for transitions in biomineralization. P. maxima larval samples most representative of these biomineralization distinctions and transitions were analyzed for differential gene expression on the microarray platform PmaxArray 1.0. A number of transcripts are reported as differentially expressed in correlation to the mineralization events of P. maxima larval ontogeny. Some of those isolated are known shell matrix genes while others are novel; these are discussed in relation to potential shell formation roles. This interdisciplinary investigation has linked the shell developments of P. maxima larval ontogeny with corresponding gene expression profiles, furthering the elucidation of shell biomineralization.

'In the hands of the Receivers': The Politics of Literacy in The Savage by David Almond and Dave McKean

David Almond and Dave McKean's The Savage is a hybrid prose and graphic novel which tells the story of one young man’s maturation through literacy. The protagonist learns to deal with the death of his father and his own 'savage' self by writing a graphic novel. This article reads The Savage in the context of earlier, 'Northern' literacy narrative - particularly Tony Harrison's poem "Them & [uz]" and Barry Hines' Kes — through the discourse of neoliberalism and the notion of the reluctant boy reader. It is suggested that Almond and McKean are influenced by currently dominant ideologies of gender and literacy.

The role of the recycling endosome in regulating lamellipodia formation and macrophage migration

Cell migration is a highly complex process that requires the extension of cell membrane in the direction of travel. This membrane is continuously remodeled to expand the leading edge and alter its membrane properties. For a long time it has been known that there is a continual flow of polarized membrane traffic towards the leading edge during migration and that this trafficking is essential for cell migration. However, there is little information on how the cell coordinates exocytosis at the leading edge. It is also unclear whether these internal membranes are incorporated into the leading edge or are just delivering the necessary proteins for migration to occur. We have shown that recycling endosome membrane is incorporated into the plasma membrane at the leading edge to expand the membrane and at the same time delivers receptors to the leading edge to mediate migration. In order for this to happen the surface Q-SNARE complex Stx4/SNAP23 translocates to the leading edge where it binds to the R-SNARE VAMP3 on the recycling endosome allowing incorporation into the plasma membrane. Loss of any one of the components of this complex reduces efficient lamellipodia formation and restrains cell migration.

…Where did I lose you? Accessing the literacy demands of assessment

In this study we sought to find out how teachers could make assessment fairer for Indigenous students in learning mathematics, given the context of the high stakes of the National Assessment Program Literacy and Numeracy (NAPLAN). Today, teachers are experiencing the full range of demands from their own students who require individual attention, through to system level expectations of improved performances for all students. Many staff experience reform fatigue with limited time for critical reflection and a reduction in support for the use and the analysis of the overwhelming amount of data that has become available in recent years. Over the past three years we worked with teachers in seven schools to gradually refine our research focus to centre on how we might best support teachers in this demanding context with the important outcome of improved teaching and learning of mathematics with particular consideration of how to respond to the cultural needs of Indigenous (Aboriginal and Torres Strait Islander) students.

Preservice teachers’ perceptions of their middle schooling teacher preparation : a sample of the Australian context

Reviews into teacher education and reform measures, such as implementing professional standards for teachers, are designed to raise the quality of education. Such reviews and reforms also target preservice teachers; hence universities examine their teacher education programs to address these issues, including developing programs that are current with the literature. Over the past fifteen years, concerns have arisen about Australian early adolescents and their disengagement from the schooling system, their “at risk” behaviour and their need for social, emotional and academic support. These concerns have prompted a middle schooling movement in Australia with the literature recognising a need for specialised middle school teachers. As a result, various universities have responded by developing courses specifically designed to graduate teachers who possess the theoretical and pedagogical knowledge for engaging early adolescent learners. This mixed-method study analysed the responses of preservice teachers from three universities across two states in Australia near the completion of their middle years teacher preparation program. The three aims of the study were to: (1) investigate final-year preservice teachers’ perceptions of their confidence to teach in the middle years of schooling; (2) analyse the experiences included in their teacher preparation course that made them feel confident; and (3) describe strategies for enhancing middle schooling teacher education preparation. Data were gathered from final-year preservice teachers (n=142) using a survey that was developed in response to middle schooling literature and the Professional Standards for Queensland Teachers (Queensland College of Teachers, 2006). A questionnaire collected extended information about the participants’ (n=142) experiences that made them feel confident. It also gathered information about strategies for enhancing middle years teacher preparation. One-to-one, 45-minute interviews (n=10) were conducted to elicit in-depth responses aligned with the research aims. Quantitative results indicated that the majority of preservice teachers (n=142) claimed confidence associated with survey items relating to creating a positive classroom environment (range: 70-97%), developing positive relationships for teaching (71-98%), pedagogical knowledge for teaching (72-95%), and implementation of teaching (70-91%). Qualitative findings suggested that the experiences that assisted them to be confident for teaching were practicum and associated field studies coursework, a positive mentor teacher, specifically designed middle years subjects, the pedagogical approaches of university staff, and other real-world experiences such as volunteering in schools and participating in professional development alongside their mentors. This study demonstrated that universities presenting middle years teacher preparation need to consider: the quality of the practicum experience; the suitability of mentor teachers; the significance and practicalities of middle years subjects; university lecturers’ modelling of pedagogical practices; and the inclusion of real-world learning experiences. Although the findings of this study provided evidence as to how preservice teacher confidence for teaching has been influenced by their middle schooling teacher preparation, further research is required to investigate how confidence translates into practice within their first years of teaching.

The formation of YBa2Cu3O7-x in melt-texture heat treatments

A study of the bulk formation of YBa2Cu3O7-x from the Y2BaCuO5 plus liquid regime reveals that phase formation occurs at appreciable rates below 950°C in air. This result has been observed for phase-pure YBa2Cu3O7-x starting material given two types of heat treatment: held at 1100°C and slow-cooled from 1030°C at 6°C/h or heat-treated isothermally. Differential thermal analysis, with a cooling rate of 10°C/min indicates that the degree of undercooling for the peritectic formation of YBa2Cu3O7-x is greater than 100°C. © 1994.

Retention and graduation of Aboriginal and Torres Strait Islander students in initial teacher education : a review of the literature

While the need to increase numbers of Indigenous teachers has been highlighted for many years, Aboriginal and Torres Strait Islander teachers are still significantly underrepresented in Australia making up less that 1% of teachers in schools. Nationally, little has changed since the 1980s when Hughes and Wilmot (1992) called for ‘1000 Indigenous teachers by 1990’. This paper reports on an initial literature review of teacher education as related to the preparation of Aboriginal and Torres Strait Islanders. Alongside the scholarly literature, the review to date includes analysis of over twenty policy documents and government reports as well as web-based descriptions of historical and current models of Indigenous teacher education including both mainstream Education programs and cohort-based and community models. While the literature provides examples of successful models of Indigenous teacher education it also illuminates the longstanding and interrelated factors that continue to impact on the success or failure of teacher education for Aboriginal and Torres Strait Islanders

Nature and genesis of clay minerals of the Rustler Formation in the vicinity of the Waste Isolation Pilot Plant in Souteastern New Mexico

Detailed mineralogical studies of the matrix and fracture-fill materials of a large number of samples from the Rustler Formation have been carried out using x-ray diffraction, high-resolution transmission electron microscopy, electron microprobe analysis, x-ray fluorescence, and atomic absorption spectrophotometry. These analyses indicate the presence of four clay minerals: interstratified chlorite/saponite, illite, chlorite, and serpentine. Corrensite (regularly stratified chlorite/saponite) is the dominant clay mineral in samples from the Culebra dolomite and two shale layers of the lower unnamed member of the Rustler Formation. Within other layers of the Rustler Formation, disordered mixed chlorite/saponite is usually the most abundant clay mineral. Studies of the morphology and composition of clay crystallites suggest that the corrensite was formed by the alteration of detrital dioctahedral smectite in magnesium-rich pore fluids during early diagenesis of the Rustler Formation. This study provides initial estimates of the abundance and nature of the clay minerals in the Culebra dolomite in the vicinity of the Waste Isolation Pilot Plant.

Formation of single-walled carbon nanotube via the interaction of graphene nanoribbons : ab initio density functional calculations

The interaction of bare graphene nanoribbons (GNRs) was investigated by ab initio density functional theory calculations with both the local density approximation (LDA) and the generalized gradient approximation (GGA). Remarkably, two bare 8-GNRs with zigzag-shaped edges are predicted to form an (8, 8) armchair single-wall carbon nanotube (SWCNT) without any obvious activation barrier. The formation of a (10, 0) zigzag SWCNT from two bare 10-GNRs with armchair-shaped edges has activation barriers of 0.23 and 0.61 eV for using the LDA and the revised PBE exchange correlation functional, respectively, Our results suggest a possible route to control the growth of specific types SWCNT via the interaction of GNRs.

Carbonate cementation in sandstones of the Plover Formation, North West Shelf, W.A

Ancient sandstones include important reservoirs for hydrocarbons (oil and gas), but, in many cases, their ability to serve as reservoirs is heavily constrained by the effects of carbonate cements on porosity and permeability. This study investigated the controls on distribution and abundance of carbonate cements within the Jurassic Plover Formation, Browse Basin, North West Shelf, Australia. Samples were analysed petrographically with point counting of 59 thin sections and mineralogically with x-ray diffraction from two wells within the Torosa Gas Field. Selected samples were also analysed for stable isotopes of O and C. Sandstones are classified into eleven groups. Most abundant are quartzarenites and then calcareous quartzarenites. Lithology ranged between sandstones consisting of mostly quartz with scant or no carbonate in the form of cement or allochems, to sandstones with as much as 40% carbonate. The major sources of carbonate cement in Torosa 1 and Torosa 4 sandstones were found to be early, shallow marine diagenetic processes (including cementation), followed by calcite cementation and recrystallisation of cements and allochems during redistribution by meteoric waters. Blocky and sparry calcite cements, indicative of meteoric environments on the basis of stable isotope values and palaeotemperature assessment, overprinted the initial shallow marine cement phase in all cases and meteoric cements are dominant. Torosa 4 was influenced more by marine settings than Torosa 1, and thus has the greater potential for calcite cement. The relatively low compaction of calcite-cemented sandstones and the stable isotope data suggest deep burial cementation was not a major factor. Insufficient volcanic rock fragments or authigenic clay content infers alteration of feldspars was not a major source of calcite. Very little feldspar is present, altered or otherwise. Hence, increased alkalinity from feldspar dissolution is not a contributing factor in cement formation. Increased alkalinity from bacterial sulphate reduction in organic–rich fine sediments may have driven limited cementation in some samples. The main definable and significant source of diagenetic marine calcite cement originated from original marine cements and the nearby dissolution of biogenic sources (allochems) at relatively shallow depths. Later diagenetic fluids emplaced minor dolomite, but this cement did not greatly affect the reservoir quality in the samples studied.

The phenomenon of information literacy

Information literacy is increasingly recognised as an important educational outcomes for university students. How it is experienced, however, has only recently become the subject of scrutiny. THe study reported here examines varying conception of information literacy amongst a group of lecturers, librarians, staff developers and learning counsellors. A phenomenographic approach was used to discover their conceptions. Data were gathered from participants, both male and female, through interviews, e-mail discussions and workshops. As an outcomes of the analysis, seven categories, or 'faces' of information literacy were discovered. These categories depict information literacy as it is conceived or experienced. They provide target conceptions for the educational process which differ from the more conventional competencies or skill-based objectives.

First-principle studies of the formation and diffusion of hydrogen vacancies in magnesium hydride

Ab initio density functional theory (DFT) calculations are performed to study the formation and diffusion of hydrogen vacancies on MgH2(110) surface and in bulk. We find that the formation energies for a single H-vacancy increase slightly from the surface to deep layers. The energies for creating adjacent surface divancacies at two inplane sites and at an inplane and a bridge site are even smaller than that for the formation of a single H-vacancy, a fact that is attributed to the strong vacancy−vacancy interactions. The diffusion of an H-vacancy from an in-plane site to a bridge site on the surface has the smallest activation barrier calculated at 0.15 eV and should be fast at room temperature. The activation barriers computed for H-vacancy diffusion from the surface into sublayers are all less than 0.70 eV, which is much smaller than the activation energy for desorption of hydrogen on the MgH2(110) surface (1.78−2.80 eV/H2). This suggests that surface desorption is more likely than vacancy diffusion to be rate determining, such that finding effective catalyst on the MgH2 surface to facilitate desorption will be very important for improving overall dehydrogenation performance.

Yarning circles in the literacy classroom

This article explains how the speaking and listening practice of yarning circles can be used in the literacy classroom. The article opens with an account of a live enactment of yarning circles with elementary students in a mainstream classroom in Australia. It explains the purpose and origin of yarning circles in Indigenous communities, and provides steps for establishing and implementing the practice in classrooms.