Stat3/Cdc25a-dependent cell proliferation promotes embryonic axis extension during zebrafish gastrulation

Cell proliferation has generally been considered dispensable for anteroposterior extension of embryonic axis during vertebrate gastrulation. Signal transducer and activator of transcription 3 (Stat3), a conserved controller of cell proliferation, survival and regeneration, is associated with human scoliosis, cancer and Hyper IgE Syndrome. Zebrafish Stat3 was proposed to govern convergence and extension gastrulation movements in part by promoting Wnt/Planar Cell Polarity (PCP) signaling, a conserved regulator of mediolaterally polarized cell behaviors. Here, using zebrafish stat3 null mutants and pharmacological tools, we demonstrate that cell proliferation contributes to anteroposterior embryonic axis extension. Zebrafish embryos lacking maternal and zygotic Stat3 expression exhibit normal convergence movements and planar cell polarity signaling, but transient axis elongation defect due to insufficient number of cells resulting largely from reduced cell proliferation and increased apoptosis. Pharmacologic inhibition of cell proliferation during gastrulation phenocopied axis elongation defects. Stat3 regulates cell proliferation and axis extension in part via upregulation of Cdc25a expression during oogenesis. Accordingly, restoring Cdc25a expression in stat3 mutants partially suppressed cell proliferation and gastrulation defects. During later development, stat3 mutant zebrafish exhibit stunted growth, scoliosis, excessive inflammation, and fail to thrive, affording a genetic tool to study Stat3 function in vertebrate development, regeneration, and disease

Spatio-temporal regulation of concurrent developmental processes by generic signaling downstream of chemokine receptors

Chemokines are secreted proteins that regulate a range of processes in eukaryotic organisms. Interestingly, different chemokine receptors control distinct biological processes, and the same receptor can direct different cellular responses, but the basis for this phenomenon is not known. To understand this property of chemokine signaling, we examined the function of the chemokine receptors Cxcr4a, Cxcr4b, Ccr7, Ccr9 in the context of diverse processes in embryonic development in zebrafish. Our results reveal that the specific response to chemokine signaling is dictated by cell-type-specific chemokine receptor signal interpretation modules (CRIM) rather than by chemokine-receptor-specific signals. Thus, a generic signal provided by different receptors leads to discrete responses that depend on the specific identity of the cell that receives the signal. We present the implications of employing generic signals in different contexts such as gastrulation, axis specification and single-cell migration.</jats:p

Preparing construction project managers to document professional growth

Deakin University&rsquo;s School of Architecture and Building is renowned for producing graduates who possess relevant attributes that make them job ready for the building and construction industry. Graduate destination surveys indicate that in the last eight (8) years, 100% of all Infrastructure Logistics (Construction and Facility Management) course graduates found relevant employment. This success is a direct result of a curriculum that is responsive to industry needs alongside educational methodology that focuses on excellent teaching and research while seeking new ways of developing and delivering courses. The Infrastructure Logistics course prepares graduates to successfully compete in today&rsquo;s global job market, and allows them to showcase relevant knowledge and skills that are critical in seeking and sustaining employment. Traditionally, tailored resumes served this purpose; however, in many professional fields, professional portfolios are now becoming a more desirable way of providing a summary of relevant attributes alongside evidence of professional abilities. Sustaining employment, appraisals, and applying for a promotion are often subject to adequate evidence of professional standards and growth. Professional bodies require records of contribution to Continuing Professional Development (CPD) schemes; and accrediting organisations require professionals applying for professional registration to provide documented evidence of their relevant experience and abilities. The Australian Institute of Project Management (AIPM 2007) requires candidates wanting to become Registered Project Managers (RegPM) to demonstrate their current work-based experience and competencies.This paper reports on a teaching strategy adopted in the Project Management (PM) stream, offered as part of Infrastructure Logistic courses. The teaching strategy is based on a combination of constructivism theory of learning, problem and project based learning, and active learning. The strategy requires systematic reflection and conscious creation of documented evidence of PM attributes and competences in the form of a portfolio.Preliminary results of action research monitoring the effectiveness of systematic reflection indicate that students respond very positively to the idea of professional journals and professional portfolios. Preliminary results also indicate that students accept reflection and conscious documentation of their achievements as an integral part of their study and future practice.<br /

The role of assessment in the development of judgement

This paper introduces an integrated assessment model developed within a project management discipline stream in a Construction Management course. Following Boud and Falchikov (2007) this model starts with practice, that is, the actual &lsquo;doing&rsquo; of project management as the basis for shaping assessment that equips students to learn for the rest of their lives. Practice is understood as a holistic conception of what professionals do in particular contexts, and a theoretical construct that provides a method of framing ways in which we can investigate the world (Schatzki, 2001). This approach opens the way for considerations of assessment that engage with, and cultivate, certain kinds of professional learning and identity formation including the development of judgement. Integral to the model is the non-sequential nature of assessment activities, evolving team formation and ongoing self and communal reflection. The paper concludes that the use of an authentic and integrated assessment model creates a compelling learning environment that contributes meaningfully to the development of skills, knowledge and identities for future professional learning.<br /

Environmentally friendly sound absorbing noise barrier made from concrete waste - further developments

This paper reports on the second phase of a research project aimed at the development of an environmentally friendly noise barrier for urban freeways, also known as KMAK [1]. The concrete barrier, which has some unique capabilities to mitigate transportation noise, is made from recycled concrete (RC) aggregate and industrial by-products such as fly ash and reclaimed water. The current developmental work expands on a research project that resulted in a two-layer (2L) concrete barrier. Two prototypes of the 2L barrier were produced, followed by extensive acoustic testing and a number of simulations where standard timber and/or concrete barriers were substituted with KMAK barrier [2]. Current research investigates a variety of architectural finishes applied to the original KMAK barrier with the aim of improving its visual appearance and also fine-tuning its acoustic performance. The new three-layer (3L) barrier optimizes sound absorption in a frequency range characteristic similar to that of transportation noise, especially road traffic noise. Three major aspects related to the development of architectural finishes were considered; environmentally responsible materials, surface features, and production methods. The findings of the current investigation demonstrate that there is a positive correlation between surface features, percentage of perforation as well as depth of the architectural layer, and increased potential of the 3L barrier to mitigate transportation noise. On average, the addition of perforated architectural finish contributes to a 20% increase in sound absorption. The preliminary results also show that the sound absorbency of the 3L barrier can be better controlled and tuned to specific noise frequency than the 2L type. The visual appearance has been significantly improved with the addition of the architectural finish, which makes the barrier an attractive, feasible, and viable alternative to road barriers made from standard concrete or timber.<br /

Ecologically sustainable noise barrier – further developments

This paper reports on the second phase of a research project aimed at the development of an environmentally friendly noise barrier for urban freeways, also known as KMAK (Krezel and McManus, 2007). The concrete barrier, which has some unique capabilities to mitigate transportation noise, is made from recycled concrete (RC) aggregate and industrial by-products such as fly ash and reclaimed water. The current developmental work expands on a research project that resulted in a two-layer (2L) concrete barrier. Two prototypes of the 2L barrier were produced, followed by extensive acoustic testing and a number of simulations where standard timber and/or concrete barriers were substituted with KMAK barrier (Krezel et al, 2004). Current research investigates a variety of architectural finishes applied to the original KMAK barrier with the aim of improving its visual appearance and also fine-tuning its acoustic performance. The new three-layer (3L) barrier optimises sound absorption in a frequency range characteristic to that of transportation noise, especially road traffic noise. Three major aspects related to the development of architectural finishes were considered; environmentally responsible materials, surface features and production methods. The light-weight material used in the architectural finish is based on ordinary Portland cement (OPC) and uses very fine fraction of RC aggregate. The manufacturing process of the 3L barrier was tested in a commercial setting and two sets of prototype barrier were cast. An innovative, cost effective method of applying pattern and perforation to the surface of architectural finish was also developed and tested. The findings of the current investigation demonstrate that there is a positive correlation between surface features, percentage of perforation as well as depth of the architectural layer and increased potential of the 3L barrier to mitigate transportation noise. On average, the addition of perforated architectural finish contributes to 20% increase in sound absorption. The preliminary results also show that the sound absorbency of the 3L barrier can be better controlled and tuned to specific noise frequency. The visual appearance has been significantly improved with the addition of the architectural finish, which makes the barrier an attractive, feasible and viable alternative to road barriers made from standard concrete or timber.<br /

Social influence and student choice of higher education institution

This conceptual paper discusses changes in higher education sector, growing competition as a result of new private education providers and the adoption of student-as-customer perspective in recruitment and marketing of higher education institutions. The paper reviews numerous models of student choice and identifies inconsistencies in the role of social factors in the student choice. These inconsistencies are of special importance in current higher education landscape and growing prominence of peer-to-peer communication via social media. Consequently, a thorough understanding of influences that effect student choice of higher education institution is imperative. This conceptual paper puts forward a conceptual framework that integrates Kelman’s processes of social influence and Cialdini-Goldstein’s goals that underpin the acceptance of that influence to examine the effects social context has on student choice of higher education institution

Nodal and planar cell polarity signaling cooperate to regulate zebrafish convergence and extension gastrulation movements

During vertebrate gastrulation, convergence and extension (C and E) of the primary anteroposterior (AP) embryonic axis is driven by polarized mediolateral (ML) cell intercalations and is influenced by AP axial patterning. Nodal signaling is essential for patterning of the AP axis while planar cell polarity (PCP) signaling polarizes cells with respect to this axis, but how these two signaling systems interact during C and E is unclear. We find that the neuroectoderm of Nodal-deficient zebrafish gastrulae exhibits reduced C and E cell behaviors, which require Nodal signaling in both cell- and non-autonomous fashions. PCP signaling is partially active in Nodal-deficient embryos and its inhibition exacerbates their C and E defects. Within otherwise naïve zebrafish blastoderm explants, however, Nodal induces C and E in a largely PCP-dependent manner, arguing that Nodal acts both upstream of and in parallel with PCP during gastrulation to regulate embryonic axis extension cooperatively

2Loud? Monitoring traffic noise with mobile phones

The World Health Organization has recently focused attention on guidelines for night noise in urban areas, based on significant medical evidence of the adverse impacts of exposure to excessive traffic noise on health, especially caused by sleep disturbance. This includes serious illnesses, such as hypertension, arteriosclerosis and myocardial infarction. 2Loud? is a research project with the aim of developing and testing a mobile phone application to allow a community to monitor traffic noise in their environment, with focus on the night period and indoor measurement. Individuals, using mobile phones, provide data on characteristics of their dwellings and systematically record the level of noise inside their homes overnight. The records from multiple individuals are sent to a server, integrated into indicators and shared through mapping. The 2Loud? application is not designed to replace existing scientific measurements, but to add information which is currently not available. Noise measurements to assist the planning and management of traffic noise are normally carried out by designated technicians, using sophisticated equipment, and following specific guidelines for outdoors locations. This process provides very accurate records, however, for being a time consuming and expensive system, it results in a limited number of locations being surveyed and long time between updates. Moreover, scientific noise measurements do not survey inside dwellings. In this paper we present and discuss the participatory process proposed, and currently under implementation and test, to characterize the levels of exposure to traffic noise of residents living in the vicinity of highways in the City of Boroondara (Victoria, Australia) using the 2Loud? application