265 research outputs found

    Engaging casually employed teachers in collaborative curriculum and professional development : change through an action research enquiry in a higher education 'pathways' institution

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    This thesis is an account of a curriculum reform initiative that took place in 2005 at the Pathways College of Australia (PCA) [a pseudonym]. It is an investigation of an innovative collaborative educational development project in an Australian higher education pathway institution. The research highlights the neglect of the professional development of casually employed teachers and makes contributions to the literatures of educational development, curriculum and collaboration. It suggests ways to improve quality in the current higher education context through a process of action research enquiry and organisational change In recent times the higher education landscape in Australia has transformed with growing numbers of casual and part-time teachers, many more international students and an increasing focus on quality assurance. This changing context has led to the emergence of a number of private institutions providing an alternative entry pathway to tertiary study for students who do not meet standard university entrance requirements. The story of PCA and its growth during this time comes out of an increasing focus on quality and accountability underpinning the funding changes to, and the internationalisation of, higher education. This study presents a curriculum development framework which engages casually employed teachers and supports curriculum reform. It addresses a need to ensure quality in the teaching and learning at PCA by developing an integrated curriculum. The framework allows for the professional development of casualised teaching staff in a pathways higher education institution and encourages a critical reflection on the process through action research. An exploration of the usefulness of communities of practice theory for examining the workings of this group-based educational development process frames the data analysis. The research contributes to the literature by analysing how the participants engaged in the project cycles and illuminates the different ways in which they were working. Insights into curriculum reform are given through building collaboration under adverse conditions. The discussion adds a new dimension to communities of practice theory as it does not account for the important set of tensions found in the data. It furthers our understanding of its application in an environment with mostly casually employed teachers. The story about this research reveals the complexities in the relationships between the researcher, the participants and PCA and shows a successful collaboration can be achieved under challenging employment conditions

    The utility of existing passerine microsatellite markers for genetic studies in endangered species: as demonstrated for a critically endangered forest bird endemic to RĂ©union Island, the RĂ©union cuckooshrike (Coracina newtoni)

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    Genetic data are increasingly recognized for their utility in conservation programs. However, many endangered species belong to families that have been understudied. Due to the urgency of their conservation status it is important to quickly identify polymorphic microsatellite loci from available resources. We show for the ReÂŽunion Cuckoo shrike Coracina newtoni, that this strategy can be very useful. Using 110 passerine microsatellite primer sets we identified eighteen polymorphic loci and tested them in 25 C. newtoni individuals. Following a Bonferroni correction one pair of loci displayed linkage disequilibriu

    c-Jun N-terminal kinase has a key role in Alzheimer disease synaptic dysfunction in vivo.

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    Altered synaptic function is considered one of the first features of Alzheimer disease (AD). Currently, no treatment is available to prevent the dysfunction of excitatory synapses in AD. Identification of the key modulators of synaptopathy is of particular significance in the treatment of AD. We here characterized the pathways leading to synaptopathy in TgCRND8 mice and showed that c-Jun N-terminal kinase (JNK) is activated at the spine prior to the onset of cognitive impairment. The specific inhibition of JNK, with its specific inhibiting peptide D-JNKI1, prevented synaptic dysfunction in TgCRND8 mice. D-JNKI1 avoided both the loss of postsynaptic proteins and glutamate receptors from the postsynaptic density and the reduction in size of excitatory synapses, reverting their dysfunction. This set of data reveals that JNK is a key signaling pathway in AD synaptic injury and that its specific inhibition offers an innovative therapeutic strategy to prevent spine degeneration in AD

    The Stimulation of Inducible Nitric-oxide Synthase by the Prion Protein Fragment 106–126 in Human Microglia Is Tumor Necrosis Factor-α-dependent and Involves p38 Mitogen-activated Protein Kinase

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    A synthetic peptide consisting of amino acid residues 106-126 of the human prion protein (PrP-(106--126)) has been previously demonstrated to be neurotoxic and to induce microglial activation. The present study investigated the expression of the inducible form of the nitric-oxide synthase (NOS-II) in human microglial cells treated with PrP-(106--126). Using reverse transcriptase-polymerase chain reaction, we found that PrP-(106--126) induces NOS-II gene expression after 24 h of treatment and that this effect is accompanied by a peak of nuclear factor kappa B (NF-kappa B) binding at 30 min as evaluated by electrophoretic mobility shift assay. Since our previous data demonstrated tumor necrosis factor-alpha (TNF-alpha) to be a potent inducer of NOS-II in these cells, we analyzed the expression of this cytokine in PrP-(106--126)-treated microglia. PrP-(106--126) caused the release of TNF-alpha as detected by enzyme-linked immunosorbent assay, and a blocking antibody, anti-TNF-alpha, abolished NOS-II induction elicited by this peptide. Moreover, PrP-(106-126) activates p38 mitogen-activated protein kinase, and the inhibition of this pathway determines the ablation of NF-kappa B binding induced by this fragment peptide

    The value of the spineless monkey orange tree (Strychnos madagascariensis) for conservation of northern sportive lemurs (Lepilemur milanoii and L. ankaranensis)

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    Tree hollows provide shelters for a large number of forest-dependent vertebrate species worldwide. In  Madagascar, where high historical and ongoing rates of deforestation and forest degradation are  responsible for a major environmental crisis, reduced availability of tree hollows may lead to declines in hollow-dwelling species such as sportive lemurs, one of the most species-rich groups of lemurs. The identification of native tree species used by hollow-dwelling lemurs may facilitate targeted management interventions to maintain or improve habitat quality for these lemurs. During an extensive survey of sportive lemurs in northern Madagascar, we identified one tree species, Strychnos madagascariensis (Loganiaceae), the spineless monkey orange tree, as a principal sleeping site of two species of northern sportive lemurs, Lepilemur ankaranensis and L. milanoii (Lepilemuridae). This tree species represented 32.5% (n=150) of the 458 sleeping sites recorded. This result suggests that S. madagascariensis may be valuable for the conservation of hollow-dwelling lemurs. De nombreux vertĂ©brĂ©s forestiers Ă  travers le monde trouvent refuge dans des cavitĂ©s et des trous  d’arbres. À Madagascar, les taux de dĂ©forestation historiques et actuels sont responsables d’une crise environnementale majeure. Dans ce contexte, une disponibilitĂ© rĂ©duite d’arbres pourvus de cavitĂ©s  pourrait entrainer le dĂ©clin des espĂšces dĂ©pendant de ces abris comme par exemple les lĂ©pilemurs, un des groupes de lĂ©muriens les plus riches en espĂšces. L’identification des espĂšces d’arbres indigĂšnes creusĂ©s de trous et utilisĂ©s par les lĂ©muriens pourrait faciliter la mise en place d’actions de conservation ayant pour but de maintenir ou amĂ©liorer l’habitat de ces lĂ©muriens. Au cours d’une Ă©tude rĂ©alisĂ©e dans le Nord de Madagascar, nous avons observĂ© que Strychnos madagascariensis  (Loganiaceae) Ă©tait   frĂ©quemment utilisĂ© comme site dortoir par les deux espĂšces de lĂ©pilemurs prĂ©sentes, Lepilemur   ankaranensis and L. milanoii (Lepilemuridae). Cette espĂšce d’arbre concernait 32,5% (n = 150) des 458  sites dortoirs enregistrĂ©s. Ce rĂ©sultat suggĂšre que S. madagascariensis pourrait ĂȘtre important pour la  conservation des lĂ©muriens dĂ©pendant de sites dortoirs

    The Molecular Assembly of Amyloid A beta Controls Its Neurotoxicity and Binding to Cellular Proteins

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    Accumulation of beta-sheet-rich peptide (A beta) is strongly associated with Alzheimer's disease, characterized by reduction in synapse density, structural alterations of dendritic spines, modification of synaptic protein expression, loss of long-term potentiation and neuronal cell death. A beta species are potent neurotoxins, however the molecular mechanism responsible for A beta toxicity is still unknown. Numerous mechanisms of toxicity were proposed, although there is no agreement about their relative importance in disease pathogenesis. Here, the toxicity of A beta 1-40 and A beta 1-42 monomers, oligomers or fibrils, was evaluated using the N2a cell line. A structure-function relationship between peptide aggregation state and toxic properties was established. Moreover, we demonstrated that A beta toxic species cross the plasma membrane, accumulate in cells and bind to a variety of internal proteins, especially on the cytoskeleton and in the endoplasmatic reticulum (ER). Based on these data we suggest that numerous proteins act as A beta receptors in N2a cells, triggering a multi factorial toxicity

    On spontaneous scalarization

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    We study in the physical frame the phenomenon of spontaneous scalarization that occurs in scalar-tensor theories of gravity for compact objects. We discuss the fact that the phenomenon occurs exactly in the regime where the Newtonian analysis indicates it should not. Finally we discuss the way the phenomenon depends on the equation of state used to describe the nuclear matter.Comment: 41 pages, RevTex, 10 ps figures, submitted to Phys. Rev.

    Monitoring the Fate of Orally Administered PLGA Nanoformulation for Local Delivery of Therapeutic Drugs

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    One of the goals of the pharmaceutical sciences is the amelioration of targeted drug delivery. In this context, nanocarrier-dependent transportation represents an ideal method for confronting a broad range of human disorders. In this study, we investigated the possibility of improving the selective release of the anti-cancer drug paclitaxel (PTX) in the gastro-intestinal tract by encapsulating it into the biodegradable nanoparticles made by FDA-approved poly(lactic-co-glycolic acid) (PLGA) and coated with polyethylene glycol to improve their stability (PLGA-PEG-NPs). Our study was performed by combining the synthesis and characterization of the nanodrug with in vivo studies of pharmacokinetics after oral administration in mice. Moreover, fluorescent PLGA-nanoparticles (NPs), were tested both in vitro and in vivo to observe their fate and biodistribution. Our study demonstrated that PLGA-NPs: (1) are stable in the gastric tract; (2) can easily penetrate inside carcinoma colon 2 (CaCo2) cells; (3) reduce the PTX absorption from the gastrointestinal tract, further limiting systemic exposure; (4) enable PTX local targeting. At present, the oral administration of biodegradable nanocarriers is limited because of stomach degradation and the sink effect played by the duodenum. Our findings, however, exhibit promising evidence towards our overcoming these limitations for a more specific and safer strategy against gastrointestinal disorders
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