394 resultados para large river


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Hollow micro-sized H2(H2O)Nb2O6 spheres constructed by nanocrystallites have been successfully synthesized via a bubble-template assisted hydrothermal process. In the reaction process, H2O2 acts as a bubble generator and plays a key role in the formation of the hollow structure. An in situ bubble-template mechanism has been proposed for the possible formation of the hollow structure. The spherelike assemblies of these H2(H2O)Nb2O6 nanoparticles have been transformed into their corresponding pseudohexagonal phase Nb2O5 through a moderate annealing dehydration process without destroying the hierarchical structure. Optical properties of the as-prepared hollow spheres were investigated. It is exciting that the absorption edge of the hollow Nb2O5 microspheres shifts about 18 nm to the violet compared with bulk powders in the UV/vis spectra, indicating its superior optical properties.

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Malaysian urban river corridors are facing major physical transformations in the 21st century. The effects of rapid development exacerbated by the competition between two key industry sectors, commercial base and tourism development in conjunction with urbanisation and industrialisation, have posted a high demand for the uses of these spaces. The political scenario and lack on consideration of ecological principles in its design solution have sparked stiff environmental and cultural constraint towards its landscape character as well as the ecological system. Therefore, a holistic approach towards improving the landscape design processes is extremely necessary to protect values of these places. Limited research has been carried out and further has created an urgent need to explore better ways to improve the landscape design processes of Malaysian urban river corridor developments that encompass the needs and aspirations of its multi-ethnic society without making any drastic changes to the landscape character of the rivers. This paper provides a brief introduction to address this significant gap and hence serves to contribute to the literature review.

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Regeneration of osseous defects by tissue-engineering approach provides a novel means of treatment utilizing cell biology, materials science, and molecular biology. The concept of in vitro cultured osteoblasts having an ability to induce new bone formation has been demonstrated in the critical size defects using small animal models. The bone derived cells can be incorporated into bioengineered scaffolds and synthesize bone matrix, which on implantation can induce new bone formation. In search of optimal cell delivery materials, the extracellular matrix as cell carriers for the repair and regeneration of tissues is receiving increased attention. We have investigated extracellular matrix formed by osteoblasts in vitro as a scaffold for osteoblasts transplantation and found a mineralized matrix, formed by human osteoblasts in vitro, can initiate bone formation by activating endogenous mesenchymal cells. To repair the large bone defects, osteogenic or stem cells need to be prefabricated in a large three dimensional scaffold usually made of synthetic biomaterials, which have inadequate interaction with cells and lead to in vivo foreign body reactions. The interstitial extracellular matrix has been applied to modify biomaterials surface and identified vitronectin, which binds the heparin domain and RGD (Arg-Gly-Asp) sequence can modulate cell spreading, migration and matrix formation on biomaterials. We also synthesized a tri-block copolymer, methoxy-terminated poly(ethylene glycol)(MPEG)-polyL-lactide(PLLA)-polylysine(PLL) for human osteoblasts delivery. We identified osteogenic activity can be regulated by the molecular weight and composition of the triblock copolymers. Due to the sequential loss of lineage differentiation potential during the culture of bone marrow stromal cells that hinderers their potential clinical application, we have developed a clonal culture system and established several stem cell clones with fast growing and multi-differentiation properties. Using proteomics and subtractive immunization, several differential proteins have been identified and verified their potential application in stem cell characterization and tissue regeneration

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The effects of rapid development have increased pressures on these places exacerbated by the competition between two key industry sectors, commercial base and tourism development. This, in supplement with urbanisation and industrialisation, has posted a high demand for the uses of these spaces. The political scenario and lack of adaptation on ecological principles and public participations in its design approach have sparked stiff environmental, historical and cultural constraint towards its landscape character as well as the ecological system. Therefore, a holistic approach towards improving the landscape design process is extremely necessary to protect human well being, cultural, environmental and historical values of these places. Limited research also has been carried out to overcome this situation. This further has created an urgent need to explore better ways to improve the landscape design process of Malaysian heritage urban river corridor developments that encompass the needs and aspirations of the Malaysian multi-ethnic society without making any drastic changes to the landscape character of the rivers. This paper presents a methodology to develop an advanced Landscape Character Assessment (aLCA) framework for evaluating the landscape character of the places, derived from the perception of two keys yet oppositional stakeholders: urban design team and special interest public. The triangulation of subjectivist paradigm methodologies: the psychophysical approach; the psychological approach; and, the phenomenological approach will be employed. The outcome will be used to improve the present landscape design process for future development of these places. Unless a range of perspectives can be brought to bear on enhancing the form and function of their future development and management, urban river corridors in the Malaysian context will continue to decline.

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Undergraduates working in teams can be a problematic endeavour, sometimes exacerbated for the student by poor prior experiences, a predisposition to an individual orientation of assessment, and simply the busyness that now typifies the life of a student. But effort in pedagogical design is worthwhile where team work is often a prerequisite in terms of graduate capabilities, robust learning, increased motivation, and indeed in terms of equipping individuals for emergent knowledge-age work practice, often epitomised by collaborative effort in both blended and virtual contexts. Through an iterative approach, based extensively on the established literature, we have developed a successful scaffold which is workable with a large cohort group (n >800), such that it affords students the lived experience of being a part of a learning network. Individuals within teams work together, to develop individual components that are subsequently aggregated and reified to an overall team knowledge artefact. We describe our case and propose a pedagogical model of scaffolding based on three perspectives: conceptual, rule-based and community-driven. This model provides designers with guidelines for producing and refining assessment tasks for team-based learning.

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Recently I asked a first year student how he was coping with the transition from high school to university. The young fellow looked at me and said, “Man, everything is so different!” I smiled and said “like what?” with which he seriously replied, “Well for one thing, no one tells you that you have to wear a hat at lunch time.” I have to admit I was a little amused and surprised by this student’s response, as so often the focus, is placed on getting first year students to engage academically, when it is obvious at times, that even the mere transition in to university life and the culture itself, can be a hurdle. While teaching, within a large first year unit for over 10 years, it has become apparent that students want more connection with not only the peers that they study with, but also with the University as a whole. Dr Krause pointed out in her keynote paper, On Being Strategic about the First Year (2006), that this “sense of belonging is conducive to enhancing engagement, satisfaction with learning and commitment to study”. It has also become evident, that the way in which students want to be able to communicate has changed, with the advent of capabilities such as Instant Messaging via a network and Short Message Service SMS texting via their hand held mobile phones. To be able to chat and feel connected on social networking sites such as Bebo, Facebook and Twitter is not only a way of the future, it is here now and it is here to stay.

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The Large scaled emerging user created information in web 2.0 such as tags, reviews, comments and blogs can be used to profile users’ interests and preferences to make personalized recommendations. To solve the scalability problem of the current user profiling and recommender systems, this paper proposes a parallel user profiling approach and a scalable recommender system. The current advanced cloud computing techniques including Hadoop, MapReduce and Cascading are employed to implement the proposed approaches. The experiments were conducted on Amazon EC2 Elastic MapReduce and S3 with a real world large scaled dataset from Del.icio.us website.

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1. A diverse array of patterns has been reported regarding the spatial extent of population genetic structure and effective dispersal in freshwater macroinvertebrates. In river systems, the movements of many taxa can be restricted to varying degrees by the natural stream channel hierarchy. 2. In this study, we sampled populations of the non-biting freshwater midge Echinocladius martini in the Paluma bioregion of tropical northeast Queensland to investigate fine scale patterns of within- and among-stream dispersal and gene flow within a purported historical refuge. We amplified a 639 bp fragment of mitochondrial COI and analysed genetic structure using pairwise ΦST, hierarchical AMOVA, Mantel tests and a parsimony network. Genetic variation was partitioned among stream sections using Streamtree to investigate the effect of potential instream dispersal barriers. 3. The data revealed strong natal site fidelity and significant differentiation among neighbouring, geographically proximate streams. We found evidence for only episodic adult flight among sites on separate stream reaches. Overall, however, our data suggested that both larval and adult dispersal was largely limited to within a stream channel. 4. This may arise from a combination of the high density of riparian vegetation physically restricting dispersal and from the joint effects of habitat stability and large population sizes. Together these may mitigate the requirement for movement among streams to avoid inbreeding and local extinction due to habitat change and may thus enable persistence of upstream populations in the absence of regular compensatory upstream flight. Taken together, these data suggest that dispersal of E. martini is highly restricted, to the scale of only a few kilometres, and hence occurs predominantly within the natal stream.

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This paper reports on the development of a tool that generates randomised, non-multiple choice assessment within the BlackBoard Learning Management System interface. An accepted weakness of multiple-choice assessment is that it cannot elicit learning outcomes from upper levels of Biggs’ SOLO taxonomy. However, written assessment items require extensive resources for marking, and are susceptible to copying as well as marking inconsistencies for large classes. This project developed an assessment tool which is valid, reliable and sustainable and that addresses the issues identified above. The tool provides each student with an assignment assessing the same learning outcomes, but containing different questions, with responses in the form of words or numbers. Practice questions are available, enabling students to obtain feedback on their approach before submitting their assignment. Thus, the tool incorporates automatic marking (essential for large classes), randomised tasks to each student (reducing copying), the capacity to give credit for working (feedback on the application of theory), and the capacity to target higher order learning outcomes by requiring students to derive their answers rather than choosing them. Results and feedback from students are presented, along with technical implementation details.

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'Surviving but not thriving.' Tbat is the message about small to mediumsized companies that Ian McRae, Chair ofthe Theatre Board of the Australia Council, has been delivering since 2003. In the Theatre Board Assessment Meeting Report of 2007, McRae strongly urged renewed financial support for this most important sector given the significant decrease over the last 10 years and the consequent decrease in new Australian works being produced. Without such support his prediction is that'considerable damage could be done to the creative infrastructure across Australia resulting in a loss of artistic vibrancy down the track that could be very difficult to recover' (McRae, 2007:3).

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Background The vast sequence divergence among different virus groups has presented a great challenge to alignment-based analysis of virus phylogeny. Due to the problems caused by the uncertainty in alignment, existing tools for phylogenetic analysis based on multiple alignment could not be directly applied to the whole-genome comparison and phylogenomic studies of viruses. There has been a growing interest in alignment-free methods for phylogenetic analysis using complete genome data. Among the alignment-free methods, a dynamical language (DL) method proposed by our group has successfully been applied to the phylogenetic analysis of bacteria and chloroplast genomes. Results In this paper, the DL method is used to analyze the whole-proteome phylogeny of 124 large dsDNA viruses and 30 parvoviruses, two data sets with large difference in genome size. The trees from our analyses are in good agreement to the latest classification of large dsDNA viruses and parvoviruses by the International Committee on Taxonomy of Viruses (ICTV). Conclusions The present method provides a new way for recovering the phylogeny of large dsDNA viruses and parvoviruses, and also some insights on the affiliation of a number of unclassified viruses. In comparison, some alignment-free methods such as the CV Tree method can be used for recovering the phylogeny of large dsDNA viruses, but they are not suitable for resolving the phylogeny of parvoviruses with a much smaller genome size.