74 resultados para FMA


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Visualization of the complex lung microvasculature and resolution of its three-dimensional architecture remains a difficult experimental challenge. We present a novel fluorescent microscopy technique to visualize both the normal and diseased pulmonary microvasculature. Physiologically relevant pulmonary perfusion conditions were applied using a low-viscosity perfusate infused under continuous airway ventilation. Intensely fluorescent polystyrene microspheres, confined to the vascular space, were imaged through confocal optical sectioning of 200 microm-thick lung sections. We applied this technique to rat lungs and the markedly enhanced depth of field in projected images allowed us to follow vascular branching patterns in both normal lungs and lungs from animals with experimentally induced pulmonary arterial hypertension. In addition, this method allowed complementary immunostaining and identification of cellular components surrounding the blood vessels. Fluorescent microangiography is a widely applicable and quantitative tool for the study of vascular changes in animal models of pulmonary disease.

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This paper provides an overview of the Australian Government’s Facilities Management (FM) Action Agenda as announced in 2004 as a key policy plank designed to facilitate growth of the FM industry. The resulting consultation with industry leaders has seen the criterion and release in April 2005 of the FM Action Agenda’s strategic plan entitled ‘Managing the Built Environment’. This framework, representing a collaboration between the Australian Government, public and private sector stakeholders and Facility Management Association of Australia (FMA Australia) and other allied bodies, sets out to achieve the vision of a more “…productive and sustainable built environment…” through improved innovation, education and standards. The 36 month implementation phase is now underway and will take a multi-pronged approach to enhancing the recognition of the FM industry and removing impediments to its growth with a 20 point action plan across the following platforms: • Innovation – Improved appreciation of facility life cycles, and greater understanding of the key drivers of workplace productivity, and the improved application of information technology. • Education and Training – Improved access to dedicated FM education and training opportunities and creation clear career pathways into the profession. • Regulatory Reform – Explore opportunities to harmonise cross jurisdictional regulatory compliance requirements that have an efficiency impact on FM. • Sustainability – Improved utilization of existing knowledge and the development of tools and opportunities to improve the environmental performance of facilities. Additional information is available at www.fma.com.au

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We investigate the roles of finn and country level agency conflicts in determining corporate payout policics. Based on a large sample of 29,610 firms in 42 countries from 2001 to 2006, we show there is a form of "pecking order" in investors' ability to extract cash (whether as dividends only or share repurchases) from firms. Although investors are able to use their legal powers to extract cash from firms in high protection countries, their ability to do so can be substantially hindered when agency costs at the firm level are high. In poor protection countries, investors seem to take whatever cash they can get, even though the amount may be small, and with scant regard for investment opportunities and firm level agency conflicts. Finally, compared to repurchases, we find dividends are more likely to be the sole method of payout in high protection countries and in non insider-dominated firms.

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We investigate whether characteristics of the home country capital environment, such as information disclosure and investor rights protection continue to affect ADRs cross-listed in the U.S. Using microstructure measures as proxies for adverse selection, we find that characteristics of the home markets continue to be relevant, especially for emerging market firms. Less transparent disclosure, poorer protection of investor rights and weaker legal institutions are associated with higher levels of information asymmetry. Developed market firms appear to be affected by whether or not home business laws are common law or civil law legal origin. Our finding contributes to the bonding literature. It suggests that cross-listing in the U.S. should not be viewed as a substitute for improvement in the quality of local institutions, and attention must be paid to improve investor protection in order to achieve the full benefits of improved disclosure. Improvement in the domestic capital market environment can attract more investors even for U.S. cross-listed firms.

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This paper examines the relationship between financial performance and ethical screening intensity of a special class of ethical funds that is rooted in Islamic values – Islamic equity funds (IEFs). These faith-based ethical funds screen investments on compliance with Islamic values where conventional interest expense (riba), gambling (maysir), excessive uncertainty (gharar), and non-ethical (non-halal) products are prohibited. We test whether these extra screens affect the financial performance of IEFs relative to non-Islamic funds. Based on a large survivorship-free international sample of 387 Islamic funds, our results show that IEFs on average underperform conventional funds by 40 basis points per month, or 4.8% per year (supporting the underperformance hypothesis). While Islamic funds do not generally perform better during crisis periods, they outperformed conventional funds during the recent sub-prime crisis (supporting the outperformance hypothesis). Using holdings-based measures for ethical screening intensity, results show IEFs that apply more intensive screening perform worse, suggesting that there is a cost to being ethical.

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O objetivo deste trabalho foi desenvolver um estudo morfológico quantitativo e qualitativo da região da sínfise mandibular (SM), através da construção de modelos tridimensionais (3D) e avaliar o seu grau de associação com diferentes classificações de padrões faciais. Foram avaliados 61 crânios secos humanos de adultos jovens com oclusão normal, com idade entre 18 e 45 anos e dentadura completa. Tomografias computadorizadas de feixe cônico (TCFC) de todos os crânios foram obtidas de forma padronizada. O padrão facial foi determinado por método antropométrico e cefalométrico. Utilizando o critério antropométrico, tomando como referência o índice facial (IF), o padrão facial foi classificado em: euriprósopo (≤84,9), mesoprósopo (85,0 - 89,9) e leptoprósopo (≥90,0). Pelo critério cefalométrico, o plano mandibular (FMA) determinou o padrão facial em curto (≤21,0), médio (21,1 - 29,0) e longo (≥29,1); e o índice de altura facial (IAF) classificou a face em hipodivergente (≥0,750), normal (0,749 - 0,650) e hiperdivergente (≤0,649). A construção de modelos 3D, representativos da região da SM, foi realizada com o auxílio do software ITK-SNAP. Os dentes presentes nesta região, incisivos, caninos e pré-molares inferiores, foram separados do modelo por técnica de segmentação semi-automática, seguida de refinamento manual. Em seguida, foram obtidos modelos 3D somente com o tecido ósseo, possibilitando a mensuraçãodo volume ósseo em mm3 (VOL) e da densidade radiográfica, pela média de intensidade dos voxels (Mvox). No programa Geomagic Studio 10 foi feita uma superposição anatômica dos modelos 3D em bestfit para estabelecer um plano de corte padronizado na linha média. Para cada sínfise foi medida a altura (Alt), a largura (Larg) e calculado o índice de proporção entre altura e largura (PAL). A avaliação da presença de defeitos alveolares foi feita diretamente na mandíbula,obtendo-se a média de todas as alturas ósseas alveolares (AltOss) e a média da dimensão das deiscências presentes (Medef). O índice de correlação intra-classe (ICC) com valores entre 0,923 a 0,994,indicou alta reprodutibilidade e confiabilidade das variáveis medidas. As diferenças entre os grupos, determinados pelas classificações do padrão facial (IF, FMA e IAF), foram avaliadas através da análise de variância (oneway ANOVA) seguida do teste post-hoc de Tukey. O grau de associação entre o padrão facial e as variáveis Vol, Mvox, PAL, Alt, Larg, AltOss e Medef foi avaliado pelo coeficiente de correlação de Pearson com um teste t para r. Os resultados indicaram ausência de diferença ou associação entre o volume, densidade radiográfica e presença de defeitos alveolares da SM e o padrão facial quando determinado pelo IF, FMA e IAF. Verificou-se tendência de SM mais longas nos indivíduos com face alongada, porém a largura não mostrou associação com o padrão facial. Estes resultados sugerem que as classificações utilizadas para determinar o padrão facial não representam satisfatoriamente o caráter 3D da face humana e não estão associadas com a morfologia da SM.

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A diversidade genética de fungos micorrízicos arbusculares (FMA) presentes na rizosfera de genótipos de milho tropicais, selecionados como contrastantes para eficiência no uso de fósforo (P), foi avaliada pela técnica de eletroforese em gel de gradiente desnaturante (DGGE). Fragmentos de DNA ribossômico (rDNA) foram amplificados por PCR, utilizando primers específicos para as famílias Acaulosporaceae e Glomaceae de fungos micorrízicos. Na análise por DGGE, os primers para as famílias Acaulosporaceae e Glomaceae foram eficientes na diferenciação das populações micorrízicas. Os genótipos de milho tiveram uma maior influência na comunidade de FMA da rizosfera do que o nível de P no solo. Os perfis de DGGE revelaram bandas que estavam presentes somente nos genótipos eficientes no uso de P (L3 e HT3060), sugerindo que alguns grupos de FMA foram estimulados por estes genótipos. As espécies Acaulospora longula, A. rugosa, A. scrobiculata, A. morrowiae e Glomus caledonium foram encontradas somente na rizosfera dos genótipos de milho eficientes no uso de P cultivados em solos com baixo teor de fósforo. Uma maior diversidade micorrízica foi encontrada nas amostras coletadas em solos de plantio direto, comparados com solos de plantio convencional. A efetiva colonização das raízes por FMA pode aumentar a eficiência de uso de P de cultivares em solos sob baixo P, influenciando a produção de milho em solos ácidos do Cerrado.

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A comunidade nativa de fungos micorrízicos arbusculares (FMA), presente em amostras de raiz e de solo rizosférico de 15 genótipos de milho contrastantes para eficiência no uso de fósforo, foi avaliada pela técnica de eletroforese em gel de gradiente desnaturante (DGGE). Foram amplificados fragmentos do DNA ribossomal com primers específicos para as famílias Acaulosporaceae e Glomeraceae. Os primers para a família Glomeraceae foram eficientes em diferenciar a estrutura da população de fungos micorrízicos, indicando grande diversidade da comunidade entre os genótipos. No DGGE específico para Glomeraceae, foram observadas bandas exclusivas nas linhagens eficientes L228-3 e L3, ambas cultivadas sob baixo teor de fósforo, indicando uma associação preferencial entre os genótipos e os simbiontes, que pode resultar em melhor eficiência na aquisição de fósforo. Além disso, a presença de Glomus clarum nestas duas linhagens eficientes, cultivadas sob baixo P, indica uma possível relação dessa espécie à tolerância ao estresse de P nesse solo. Com relação à família Acaulosporaceae, a técnica de DGGE detectou pouca variação entre os genótipos cultivados em baixo P, além de menor diversidade de fungos micorrízicos dessa família colonizando as raízes de milho.

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The pervasiveness of personal computing platforms offers an unprecedented opportunity to deploy large-scale services that are distributed over wide physical spaces. Two major challenges face the deployment of such services: the often resource-limited nature of these platforms, and the necessity of preserving the autonomy of the owner of these devices. These challenges preclude using centralized control and preclude considering services that are subject to performance guarantees. To that end, this thesis advances a number of new distributed resource management techniques that are shown to be effective in such settings, focusing on two application domains: distributed Field Monitoring Applications (FMAs), and Message Delivery Applications (MDAs). In the context of FMA, this thesis presents two techniques that are well-suited to the fairly limited storage and power resources of autonomously mobile sensor nodes. The first technique relies on amorphous placement of sensory data through the use of novel storage management and sample diffusion techniques. The second approach relies on an information-theoretic framework to optimize local resource management decisions. Both approaches are proactive in that they aim to provide nodes with a view of the monitored field that reflects the characteristics of queries over that field, enabling them to handle more queries locally, and thus reduce communication overheads. Then, this thesis recognizes node mobility as a resource to be leveraged, and in that respect proposes novel mobility coordination techniques for FMAs and MDAs. Assuming that node mobility is governed by a spatio-temporal schedule featuring some slack, this thesis presents novel algorithms of various computational complexities to orchestrate the use of this slack to improve the performance of supported applications. The findings in this thesis, which are supported by analysis and extensive simulations, highlight the importance of two general design principles for distributed systems. First, a-priori knowledge (e.g., about the target phenomena of FMAs and/or the workload of either FMAs or DMAs) could be used effectively for local resource management. Second, judicious leverage and coordination of node mobility could lead to significant performance gains for distributed applications deployed over resource-impoverished infrastructures.

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This thesis is concerned with inductive charging of electric vehicle batteries. Rectified power form the 50/60 Hz utility feeds a dc-ac converter which delivers high-frequency ac power to the electric vehicle inductive coupling inlet. The inlet configuration has been defined by the Society of Automotive Engineers in Recommended Practice J-1773. This thesis studies converter topologies related to the series resonant converter. When coupled to the vehicle inlet, the frequency-controlled series-resonant converter results in a capacitively-filtered series-parallel LCLC (SP-LCLC) resonant converter topology with zero voltage switching and many other desirable features. A novel time-domain transformation analysis, termed Modal Analysis, is developed, using a state variable transformation, to analyze and characterize this multi-resonant fourth-orderconverter. Next, Fundamental Mode Approximation (FMA) Analysis, based on a voltage-source model of the load, and its novel extension, Rectifier-Compensated FMA (RCFMA) Analysis, are developed and applied to the SP-LCLC converter. The RCFMA Analysis is a simpler and more intuitive analysis than the Modal Analysis, and provides a relatively accurate closed-form solution for the converter behavior. Phase control of the SP-LCLC converter is investigated as a control option. FMA and RCFMA Analyses are used for detailed characterization. The analyses identify areas of operation, which are also validated experimentally, where it is advantageous to phase control the converter. A novel hybrid control scheme is proposed which integrates frequency and phase control and achieves reduced operating frequency range and improved partial-load efficiency. The phase-controlled SP-LCLC converter can also be configured with a parallel load and is an excellent option for the application. The resulting topology implements soft-switching over the entire load range and has high full-load and partial-load efficiencies. RCFMA Analysis is used to analyze and characterize the new converter topology, and good correlation is shown with experimental results. Finally, a novel single-stage power-factor-corrected ac-dc converter is introduced, which uses the current-source characteristic of the SP-LCLC topology to provide power factor correction over a wide output power range from zero to full load. This converter exhibits all the advantageous characteristics of its dc-dc counterpart, with a reduced parts count and cost. Simulation and experimental results verify the operation of the new converter.

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The recent history and current trends in the collection and archiving of forest information and models is reviewed. The question is posed as to whether the community of forest modellers ought to take some action in setting up a Forest Model Archive (FMA) as a means of conserving and sharing the heritage of forest models that have been developed over several decades. The paper discusses the various alternatives of what an FMA could be, and should be. It then goes on to formulate a conceptual model as the basis for the construction of a FMA. Finally the question of software architecture is considered. Again there are a number of possible solutions. We discuss the alternatives, some in considerable detail, but leave the final decisions on these issues to the forest modelling community. This paper has spawned the “Greenwich Initiative” on the FMA. An internet discussion group on the topic will be started and launched by the “Trafalar Group”, which will span both IUFRO 4.1 and 4.11, and further discussion is planned to take place at the Forest Modelling Conference in Portugal, June 2002.