10 resultados para critical intraband interaction

em Deakin Research Online - Australia


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Over the past decade, many questions have been raised about graduates' clinical competence and fitness for practice upon completion of their undergraduate education. Despite the significance of this issue, the perspectives of registered nurses have rarely been examined. This systematic review explores the perceptions of experienced registered nurses regarding the clinical competence of new nursing graduates. Original research studies published between 2004-2014 were identified using electronic databases, reference lists, and by searching "grey literature." Papers were critically reviewed and relevant data extracted and synthesized using an approach based on Preferred Reporting Items for Systematic Reviews and Meta-Analysis. From 153 studies initially identified, 15 original research papers were included. Four main research themes were identified: clinical/technical skills, critical thinking, interaction/communication, and overall readiness for practice. Areas of concern in relation to the clinical competence of new nursing graduates specifically related to two themes: critical thinking and clinical/technical skills. Further research is required on strategies identified within the literature with the ultimate aim of ensuring new nursing graduates are safe and competent practitioners.

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In this article, we explore the role of the C-terminus (V5 domain) of PKCvar epsilon plays in the catalytic competence of the kinase using serial truncations followed by immune-complex kinase assays. Surprisingly, removal of the last seven amino acid residues at the C-terminus of PKCvar epsilon resulted in a PKCvar epsilon-Δ731 mutant with greatly reduced intrinsic catalytic activity while truncation of eight amino acid residues at the C-terminus resulted in a catalytically inactive PKCvar epsilon mutant. Computer modeling and molecular dynamics simulations showed that the last seven and/or eight amino acid residues of PKCvar epsilon were involved in interactions with residues in the catalytic core. Further truncation analyses revealed that the hydrophobic phosphorylation motif was dispensable for the physical interaction between PKCvar epsilon and 3-phosphoinositide-dependent kinase-1 (PDK-1) as the PKCvar epsilon mutant lacking both the turn and the hydrophobic motifs could still be co-immunoprecipitated with PDK-1. These results provide fresh insights into the biochemical and structural basis underlying the isozyme-specific regulation of PKC and suggest that the very C-termini of PKCs constitute a promising new target for the development of novel isozyme-specific inhibitors of PKC.

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Changing the nature of institutionalised education is the central theme of the thesis. The potential for radical changes to classroom teaching and to inservice teacher education is considered through four curriculum and teaching reform projects structured by action -research. The problems explored through the thesis are at the levels of teaching, institutional and research practices. It is argued that the professional activity of teachers, administrators, consultants, teacher educators and researchers can be understood to be tightly bound and determined by rules for acceptable professional ways of acting which are often unquestioned and unexamined by educators themselves. It is further argued that institutionalised education is dominated by ways of thinking and acting that are inherently individualistic. The thesis analyses the ideological character of this 'individualistic1 structuring of educational practice, identifying belief systems that hold the lived reality of educators and students in place. The thesis endeavours to show that the bureaucratic character of institutionalised education primarily serves and maintains the interests of dominant groups. The thesis examines the possibilities for radical reform in classroom teaching, the support teachers need when embarking on curriculum and teaching change processes, and the possible outcomes of such reform. The thesis also examines the interaction between the institutional practices of schools, universities and regional offices in the Ministry of Education in Victoria, Australia on these reform processes in classrooms. Finally, the thesis examines the potential of action research as a research and educative process in the professional development of educators who are both critically aware of the ideological nature of institutionalised education and committed to collective social action. From the analyses of the four action research projects the thesis concludes that action research has the potential to transform institutionalised education when its own practice is firstly, developed as a liberating pedagogy and not as research projects structured by individualistic and paternalistic interests; secondly, is driven by a commitment to the political struggle for equity and social justice; and thirdly, is itself an expression of communitarian work. The thesis concludes that the transformative processes associated with action research under these conditions hold the promise of democratising the 'individualistic' character of institutional education.

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This study explores the notion of contestation in environmental education. Contestation is a process in which self-interested individuals and groups in a social organisation cooperate, compete and negotiate in a complex interaction aimed at solving social problems. A "framework for critique" is developed, comprising technicist, liberalcritical paradigms in each of scientific knowledge, educational innovation, educational research and education itself. This framework forms the basis from which a critique is mounted of contesting perspectives in environmental education at international, national and local levels. The thesis argues, firstly, that contestation takes place in the domains of (a) language or "policy in environmental education; (b) organisational strategies aimed at initiating or improving environmental education; (c) educational practices conducted in the name of environmental education; and (d) within perspectives between these domains. The thesis argues, secondly, that the presently dominant techniqist models of innovation expressed in the organisation of environmental education are part of an hegemonic relationship which acts to "technologise" the innovation: they provide an organisational strategy for establishing environmental and educational progress without offering a theory for self-reflection and ideology-critique. The incompatibility of certain contesting perspectives and practices is masked, thus contributing to continuity, rather than reform. The thesis characterises this "educational problem of environmental education" as a series of theory-practice gaps at all levels, where "theory" is the set of beliefs and assumptions held by individual practitioners, and in. terms of which they understand their educational practices. An educational problem exists because these theory-practice gaps exist; the educational problem continues because these theory-practice gaps exist unacknowledged within the infrastructure of environmental education due to the effects of false consciousness and hegemony. The thesis addresses the issue of which of several contesting forms of educational research offers the most coherent response to the educational problem of environmental education, and argues that, for the time being, approaches grounded in the critical social sciences are both the best justified and most promising approaches . to educational research for environmental education.

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Amyloid aggregates, found in patients that suffer from Alzheimer's disease, are composed of fibril-forming peptides in a β-sheet conformation. One of the most abundant components in amyloid aggregates is the β-amyloid peptide 1–42 (Aβ 1–42). Membrane alterations may proceed to cell death by either an oxidative stress mechanism, caused by the peptide and synergized by transition metal ions, or through formation of ion channels by peptide interfacial self-aggregation. Here we demonstrate that Langmuir films of Aβ 1–42, either in pure form or mixed with lipids, develop stable monomolecular arrays with a high surface stability. By using micropipette aspiration technique and confocal microscopy we show that Aβ 1–42 induces a strong membrane destabilization in giant unilamellar vesicles composed of palmitoyloleoyl-phosphatidylcholine, sphingomyelin, and cholesterol, lowering the critical tension of vesicle rupture. Additionally, Aβ 1–42 triggers the induction of a sequential leakage of low- and high-molecular-weight markers trapped inside the giant unilamellar vesicles, but preserving the vesicle shape. Consequently, the Aβ 1–42 sequence confers particular molecular properties to the peptide that, in turn, influence supramolecular properties associated to membranes that may result in toxicity, including: 1), an ability of the peptide to strongly associate with the membrane; 2), a reduction of lateral membrane cohesive forces; and 3), a capacity to break the transbilayer gradient and puncture sealed vesicles.

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Angiotensin (Ang) I-converting enzyme (ACE) is a Zn2+ metalloprotease with two homologous catalytic domains. Both the N- and C-terminal domains are peptidyl dipeptidases. Hydrolysis by ACE of its decapeptide substrate Ang I is increased by Cl−, but the molecular mechanism of this regulation is unclear. A search for single substitutions to Gln among all conserved basic residues (Lys/Arg) in human ACE C-domain identified R1098Q as the sole mutant that lacked Cl− dependence. Cl−dependence is also lost when the equivalent Arg in the N-domain, Arg500, is substituted with Gln. The Arg1098 to Lys substitution reduced Cl− binding affinity by ∼100-fold. In the absence of Cl−, substrate binding affinity (1/K m) of and catalytic efficiency (k cat/K m) for Ang I hydrolysis are increased 6.9- and 32-fold, respectively, by the Arg1098 to Gln substitution, and are similar (<2-fold difference) to the respective wild-type C-domain catalytic constants in the presence of optimal [Cl−]. The Arg1098 to Gln substitution also eliminates Cl− dependence for hydrolysis of tetrapeptide substrates, but activity toward these substrates is similar to that of the wild-type C-domain in the absence of Cl−. These findings indicate that: 1) Arg1098 is a critical residue of the C-domain Cl−-binding site and 2) a basic side chain is necessary for Cl− dependence. For tetrapeptide substrates, the inability of R1098Q to recreate the high affinity state generated by the Cl−-C-domain interaction suggests that substrate interactions with the enzyme-bound Cl− are much more important for the hydrolysis of short substrates than for Ang I. Since Cl− concentrations are saturating under physiological conditions and Arg1098 is not critical for Ang I hydrolysis, we speculate that the evolutionary pressure for the maintenance of the Cl−-binding site is its ability to allow cleavage of short cognate peptide substrates at high catalytic efficiencies.

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Receptor activity-modifying proteins (RAMPs) interact with and modify the behavior of the calcitonin receptor (CTR) and calcitonin receptor-like receptor (CLR). We have examined the contribution of the short intracellular C terminus, using constructs that delete the last eight amino acids of each RAMP. C-Terminal deletion of individual RAMPs had little effect on the signaling profile induced when complexed with CLR in COS-7 or human embryonic kidney (HEK)293 cells. Likewise, confocal microscopy revealed each of the mutant RAMPs translocated hemagglutinin-tagged CLR to the cell surface. In contrast, a pronounced effect of RAMP C-terminal truncation was seen for RAMP/CTRa complexes, studied in COS-7 cells, with significant attenuation of amylin receptor phenotype induction that was stronger for RAMP1 and -2 than RAMP3. The loss of amylin binding upon C-terminal deletion could be partially recovered with overexpression of Gαs, suggesting an impact of the RAMP C terminus on coupling of G proteins to the receptor complex. In HEK293 cells the c-Myc-RAMP1 C-terminal deletion mutant showed high receptor-independent cell surface expression; however, this construct showed low cell surface expression when expressed alone in COS-7 cells, indicating interaction of RAMPs with other cellular components via the C terminus. This mutant also had reduced cell surface expression when coexpressed with CTR. Thus, this study reveals important functionality of the RAMP C-terminal domain and identifies key differences in the role of the RAMP C terminus for CTR versus CLR-based receptors.

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Multiple studies have demonstrated an association between cigarette smoking and increased anxiety symptoms or disorders, with early life exposures potentially predisposing to enhanced anxiety responses in later life. Explanatory models support a potential role for neurotransmitter systems, inflammation, oxidative and nitrosative stress, mitochondrial dysfunction, neurotrophins and neurogenesis, and epigenetic effects, in anxiety pathogenesis. All of these pathways are affected by exposure to cigarette smoke components, including nicotine and free radicals. This review critically examines and summarizes the literature exploring the role of these systems in increased anxiety and how exposure to cigarette smoke may contribute to this pathology at a biological level. Further, this review explores the effects of cigarette smoke on normal neurodevelopment and anxiety control, suggesting how exposure in early life (prenatal, infancy, and adolescence) may predispose to higher anxiety in later life. A large heterogenous literature was reviewed that detailed the association between cigarette smoking and anxiety symptoms and disorders with structural brain changes, inflammation, and cell-mediated immune markers, markers of oxidative and nitrosative stress, mitochondrial function, neurotransmitter systems, neurotrophins and neurogenesis. Some preliminary data were found for potential epigenetic effects. The literature provides some support for a potential interaction between cigarette smoking, anxiety symptoms and disorders, and the above pathways; however, limitations exist particularly in delineating causative effects. The literature also provides insight into potential effects of cigarette smoke, in particular nicotine, on neurodevelopment. The potential treatment implications of these findings are discussed in regards to future therapeutic targets for anxiety. The aforementioned pathways may help mediate increased anxiety seen in people who smoke. Further research into the specific actions of nicotine and other cigarette components on these pathways, and how these pathways interact, may provide insights that lead to new treatment for anxiety and a greater understanding of anxiety pathogenesis.

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This review will discuss Hun Joon Kim’s important work on political dissent in the Republic of Korea, The Massacres at Mt. Halla: sixty years of truth-seeking in South Korea (Massacres at Mt. Halla). This book tells the story of the six-decade-long grassroots campaign to establish a truth commission into the events around Jeju 4.3: a series of counterinsurgency actions against armed uprisings that resulted in the large-scale massacre of civilians as well as other atrocities. Political activism looms large in South Korea’s modern political history, making a major contribution to the evolution of democracy in that country. For decades, the main game, and the focus of most academic scholarship, was the establishment of full participatory democracy in the country. Yet, behind the scenes and on the peripheries, many lower profile battles have been fought and the fate of these struggles is in some ways the real test of democracy in South Korea (Republic of Korea or ROK). Drawing together a broad range of primary documentary and interview material, Massacres at Mt. Halla makes a number of important contributions to audiences in Korean Studies, International Relations, and transitional justice. Kim brings to English speakers an unprecedented insight into the uprising, counterinsurgency operations, and activist efforts to bring this chapter of South Korean history to light. Careful archival research is supplemented with detailed personal interview data, the majority of which is in the Korean language and thus previously inaccessible to a wider audience. The value here lies with a detailed narrative that traces grassroots activism from the days of authoritarian government through the varied challenges of a newly democratic nation. In its telling, this story illuminates the ways in which local activism can be derailed or suppressed in a tight security environment. In this case, the backdrop was a political environment strictly managed by the state on the grounds of a fervent anti-communist policy. Anti-communism was in fact the only state-sanctioned ideology, one which had the backing of the ROK’s powerful US military ally. As Kim’s research demonstrates in a clear way, any activism that could be perceived to deviate from this ideology was harshly dealt with. The dawn of progressive government in South Korea in 1997 brought an end to explicit ‘red-baiting’,1 as it was known, but did not overturn altogether the rigid anti-communist structures that had accompanied the development of the modern South Korean state. In the following discussion, I first provide a brief introduction to Kim’s book before focusing my attention in on what Massacres at Mt. Halla tells us about this interaction between national security discourse and civil society activism.

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Additive Manufacturing (AM) includes a range of approaches that correlate with computer aided design (CAD) and manufacturing by fabrication via precise layers and is a promising method for the production of medical tools. In this study, different aspects and mechanisms of solidification for curved surfaces based on equilibrium at curved interfaces, Monge patch, interfacial and Gibbs energy will be discussed. Also, the effect of capillarity, geometry, substrate temperature, cooling rate and scanning parameters in the solidification of a prosthetic acetabular cup (PAC) using selective laser melting (SLM) is analysed. The contributions of this work are analysing solidification and effective factors in this process to produce parts with a higher quality and mechanical properties such as strength, strain, porosity, relative density and hardness. Results indicate that due to the surface to volume (S/V) ratio, and the increasing effect of the radius on Monge patch, thermal stresses and surface forces are more prevalent on outer surfaces. Moreover, solidification and mechanical properties are related to capillarity, geometry, substrate temperature, cooling rate, scanning power and speed. The results also indicate the interaction of solute diffusion and heat transfer with interatomic forces in large S/V ratio and at small scales tend to improve solidification.