602 research outputs found
Active noise control in finite length ducts
No full textA simple technique for the active control of sound in ducts, initially suggested by Olson and May [1], is investigated in detail. A simple, "virtual earth" principle, feedback loop is used to drive the sound pressure to a minimum at a microphone placed close to a loudspeaker in the duct wall. This produces a reflection of downstream travelling plane waves. A detailed investigation of the loudspeaker near field has enabled the optimum position of the microphone to be identified. The system is shown to be especially effective at the frequencies of the longitudinal duct resonances, where the acoustic response of the duct produces a high loop gain. Results are presented which show a reduction of up to 20 dB in the amplitude of low frequency broadband noise at a position downstream of the cancelling source.</p
A study of zinc transporter 1 and its role in Type 3 Haemochromatosis
No full textHereditary haemochromatosis is an autosomal recessive disorder of iron metabolism, characterised by increased iron absorption and progressive iron accumulation particularly in the liver. It has been shown that hepatocytes can acquire iron in two forms; transferrin-bound iron (TBI) and non-transferrin-bound iron (NTBI)1. Known transporters of NTBI into the cell include DMT1 and ZIP14, and FPN is the only transporter known to export iron.
The aims of this study were to characterize the zinc transporter, ZnT-1 and determine whether it is involved in iron transport, specifically as an exporter.
There was a decrease in mRNA expression of the short untranslated isoform of ZnT-1 in double mutant (Hfe -/- and TfR2 Y245X) mouse liver, a trend also seen in TfR1 and Hamp. The long untranslated isoform, however, was significantly higher in the iron-deficient mice as was expression of TfR1 and Ferroportin. Iron and zinc efflux was measured in cells over-expressing ZnT-1 and control cells. There was no difference between over-expressed and control cells in iron efflux. However, at 60 min, over-expressed cells had significantly more zinc efflux than control cells. More zinc than iron was released from the cell.
The results of this study do not support the hypotheses that (i) ZnT-1 reduces intracellular cytoplasmic iron concentration by promoting efflux and 2 ZnT-1 is down-regulated in iron-loaded cells
The Role of Fault in Separation and Divorce. Italian Law
No full textThe books collects essays from different legal systems. It results after a research on "The role of fault in divorce" funded by the Nuffield Foundation (U.K.
An essay concerning the outward and salutary application of oils on the human body: By the Rev. William Martin Trinder, MD.
No full textImproving the network scalability of Erlang
No full textAs the number of cores grows in commodity architectures so does the like- lihood of failures. A distributed actor model potentially facilitates the de- velopment of reliable and scalable software on these architectures. Key com- ponents include lightweight processes which ‘share nothing’ and hence can fail independently. Erlang is not only increasingly widely used, but the un- derlying actor model has been a beacon for programming language design, influencing for example Scala, Clojure and Cloud Haskell.
While the Erlang distributed actor model is inherently scalable, we demon- strate that it is limited by some pragmatic factors. We address two network scalability issues here: globally registered process names must be updated on every node (virtual machine) in the system, and any Erlang nodes that com- municate maintain an active connection. That is, there is a fully connected O(n^2) network of n nodes.
We present the design, implementation, and initial evaluation of a con- servative extension of Erlang – Scalable Distributed (SD) Erlang. SD Erlang partitions the global namespace and connection network using s groups. An s group is a set of nodes with its own process namespace and with a fully connected network within the s group, but only individual connections out- side it. As a node may belong to more than one s group it is possible to construct arbitrary connection topologies like trees or rings
Letting in the Trojan mouse: Using an eportfolio system to re-think pedagogy.
No full textCopyright statement: Copyright 2008 Julie Hughes. The author assigns to ascilite and educational non-profit institutions a non-exclusive licence to use this document for personal use and in courses of instruction provided that the article is used in full and this copyright statement is reproduced. The author also grants a non-exclusive licence to ascilite to publish this document on the ascilite web site and in other formats for Proceedings ascilite Melbourne 2008. Any other use is prohibited without the express permission of the author.E-learning research, as an emergent field in the UK, is highly political in nature (Conole & Oliver, 2007, p.6) occupying a complex landscape which houses policy-makers, researchers and practitioners. Increasingly and more interestingly, the landscape is being shaped by the narratives and experiences of the learners themselves (Creanor et al., 2006, Conole et al., 2006) and the use of Web 2.0 technologies. However, as Laurillard (2007, p.xv) reminds us we still, ‘tend to use technology to support traditional modes of teaching’ and ‘we scarcely have the infrastructure, the training, the habits or the access to the new technology, to be optimising its use just yet’ (p.48). Web 2.0 spaces, literacies and practices offer the possibility for new models of education (Mayes & de Freitas, 2007, p.13) which support iterative and integrative learning but as educators and higher educational establishments are we prepared and ready to re-think our pedagogies and re-do (Beetham & Sharpe 2007, p.3) our practices? This concise paper will reflect upon how the use of new learning landscapes such as eportfolios might offer us the opportunity to reflect upon the implications of letting in the e-learning eportfolio Trojan mouse (Sharpe & Oliver, 2007, p.49)
Our emblem [music] : (Australian national song) /
No full textFor voice and piano.; Caption title.; Cover bears ill. of a kangaroo and an emu on grass.; "J.R. Coxon, The 'Centreway' Geelong West"--At bottom of p. 2.; "The men who made our emblem ... a hundred years ago ..."--From the lyrics.; Publication date approximated from the lyrics and the existence of J.R. Coxon (from Victorian Heritage Database place details); Also available online http://nla.gov.au/nla.mus-vn5432352; From the collection of Keith Watson. ANL.Title from cover: Australian national song, entitled 'Our emblem' on the emu anc kangaroo. 'Neither goes backwards.' : advance Australi
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Learning from Digital Natives: Bridging Formal and Informal Learning. Final Report
No full textOverview
This report suggests that students are increasingly making use of a variety of etools (such as mobile phones, email, MSN, digital cameras, games consoles and social networking sites) to support their informal learning within formalised educational settings, and that they use the tools that they have available if none are provided for them. Therefore, higher education institutions should encourage the use of these tools.
Aims and background
This study aimed to explore how e-tools (such as mobile phones, email, MSN, digital cameras, games consoles and social networking sites) and the processes that underpin their use can support learning within educational institutions and help improve the quality of students’ experiences of learning in higher education (pgs 9-11).
Methodology
The study entailed: (i) desk research to identify related international research and practice and examples of integration of e-tools and learning processes in formal educational settings; (ii) a survey of 160 engineering and social work students across two contrasting Scottish universities (pre- and post-1992) – the University of Strathclyde and Glasgow Caledonian University – and follow-up interviews with eight students across the two subject areas to explore which technologies students were using for both learning and leisure activities within and outside the formal educational settings and how they would like to use such technologies to support their learning in both formal and informal settings; and (iii) interviews with eight members of staff from across the institutions and two subject areas to identify their perceptions of the educational value of the e-tools. (pgs 24-27).
Key findings
• Students reported making extensive use of a variety of both e-tools (such as mobile phones, email, MSN, digital cameras) and social networking tools (such as Bebo, MySpace, Wikipedia and YouTube) for informal socialisation, communication, information gathering, content creation and sharing, alongside using the institutionally provided technologies and learning environments.
• Most of the students owned their own computer or had access to a sibling or parent’s computer. Many students owned a laptop but preferred not to bring it onto campus due to security concerns and because they found it too heavy to carry about.
• Ownership of mobile phones was ubiquitous.
• Whilst the students’ information searching literacy seemed adequate, the ability of these students to harness the power of social networking tools and informal processes for their learning was low.
Staff reported using a few Web 2.0 and social software tools but they were generally less familiar with how these could be used to support learning and teaching. There were misconceptions surrounding the affordances of the tools and fears expressed about security and invasion of personal space. Considerations of the costs and the time it would take staff to develop their skills meant that there was a reluctance to take up new technologies at an institutional level.
• Subject differences emerged in both staff and student perceptions as to which type of tools they would find most useful. Attitudes to Web 2.0 tools were different. Engineers were concerned with reliability, using institutional systems and inter-operability. Social workers were more flexible because they were focused on communication and professional needs.
• The study concluded that digital tools, personal devices, social networking software and many of the other tools explored all have a large educational potential to support learning processing and teaching practices. Therefore, use of these tools and processes within institutions, amongst staff and students should be encouraged.
• The report goes on to suggest ways in which the use of such technologies can help strengthen the links between informal and formal learning in higher education. The recommendations are grouped under four areas – pedagogical, socio-cultural, organisational and technological
DETERMINAÇÃO DOS TEORES DE ÁCIDO ACETILSALICÍLICO EM AMOSTRAS DE PLASMA POR ESPECTROFOTOMETRIA Doi: http://dx.doi.org/10.5892/ruvrd.v11i2.239250
No full textO monitoramento terapêutico constitui atividade sistemática de análise de fármacos e seus metabólitos ativos em material biológico, com o objetivo de se obter a máxima eficácia terapêutica com mínimo ou ausência de efeitos tóxicos. É recomendada para pacientes que usam Ácido Acetilsalicílico (AAS) de forma crônica, devido à alta variabilidade interindividual das concentrações plasmáticas e a baixa adesão de alguns pacientes. Assim, o objetivo deste trabalho foi o de determinar os teores de AAS em amostras de plasma, de pacientes em uso de ácido acetilsalicílico (100mg), atendidos no Programa de Saúde da Família (PSF 14) de Lavras – MG, visando monitorização terapêutica. Foram selecionados 10 pacientes, maiores de 18 anos e de ambos os sexos, sob uso de AAS 100 mg em diferentes regimes de dosagem. Essas amostras foram coletadas imediatamente antes da ingestão da próxima dose (concentração vale) e foram analisadas pelo método espectrofotométrico de Trinder, (λ 540nm). Para cálculo de teor de AAS em plasma utilizou-se a equação (y = 0,0197x + 0,0157), com um coeficiente de determinação (R2) de 0,9996. Foram encontrados valores entre 0,0 e 3,67mg%. Metade dos pacientes analisados, provavelmente, não estava aderindo ao tratamento ou ainda estavam em dose subterapêutica; o que pode ser justificado pela alta frequência com que são relatados os efeitos adversos. O método de Trinder é fácil, rápido e aplicável para prática clínica. Mas ainda é necessária a determinação de valores de referência específicos para a dosagem de AAS no plasma, quando este é administrado em baixas doses (efeito anticoagulante)
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