904 resultados para economics of research and experimental development


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Juvenile tiger prawns (Penaeus semisulcatus De Haan and P. esculentus Haswell) show a strong association with vegetated habitats and are rarely caught on non-vegetated areas. This pattern of distribution may be caused by postlarvae selecting vegetation when they settle, or to differences in post-settlement mortality in different habitats. In this study, we examined whether the postlarvae and early juvenile stages of P. semisulcatus would distinguish between seagrass (Zostera capricorni Aschers) without epiphytes, artificial seagrass and bare substratum in the laboratory. The responses of prawns reared from the egg to different stages of postlarval and juvenile development were tested to determine whether, and when, each size class showed a response to a particular habitat. Five size classes of postlarvae (average carapace lengths [CL] of 1.2, 1.4, 1.6, 1.7 and 2.0 mm) were offered a choice between Z. capricorni and bare sand. Small size classes of postlarvae either did not respond to Z. capricorni (1.2 and 1.6 mm CL), or were more abundant on bare substratum than Z. capricorni. In contrast, the largest size classes of postlarvae (1.7 and 2.0 mm CL) were more abundant on Z. capricorni during the day but not at night. The behaviour of postlarvae changed markedly at a size of 1.7 mm CL (22 days from the first nauplius): smaller postlarvae frequently swam in the water column; 1.7 and 2.0 mm CL postlarvae spent much more. time resting on the substrate and perched on seagrass leaves. This size at which postlarvae first respond to seagrass during the day, and show mainly benthic behaviour, is similar to the size at which they are found on shallow seagrass beds in northern Australia. Large postlarvae (2.7 mm CL) and juveniles (4.1 mm CL) both were more abundant on artificial seagrass than bare sand during the day but not at night, indicating that they respond to structured habitats. When large postlarvae (2.4 mm CL) and juveniles (3.5 mm CL) were offered a choice between Z. capricorni without epiphytes and artificial seagrass, they were more abundant on the Z. capricorni, which suggests that chemical cues from seagrass may explain some of the responses of P. semisulcatus to seagrass. (C) 1997 Elsevier Science B.V.

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Tese de doutoramento, Ciências Biomédicas (Neurociências), Universidade de Lisboa, Faculdade de Medicina, 2014

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This research acknowledges the difficulties experienced by teachers presenting integrated arts curricula. Instructional support is offered by arts organizations that provide arts partnerships with local schools boards. The study focuses on the experiences of 8 teachers from a Catholic school board in southern Ontario who participated in integrated arts programs offered by The Royal Conservatory of Music's Learning Through the Arts™ (LTTATM) program and a local art gallery's Art Based Integrated Learning (ABIL) program and examines their responses to the programs and their perception of personal and professional development through this association. Additionally, questions were posed to the . "aftisfs"from-tneSe]Jfograrrrs;-and"they liiscus·sed·how"participating in-collaboration with teachers in the development of in-school programs enabled them to experience personal and professional development as well. Seven themes emerged from the data. These themes included: teachers' feelings of a lack of preparedness to teach the arts; the value of the arts and arts partnerships in schools; the role of the artists in the education of teachers; professional development for both teachers and artists; the development of collegiality; perceptions of student engagement; and the benefits and obstacles of integrating the arts into the curriculum. This document highlights the benefits to both teachers and artists of arts partnerships between schools and outside arts organizations.

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This paper examines the intellectual and professional contribution of comparative and international studies to the field of education. It explores the nature of the challenges that are currently being faced, and assesses its potential for the advancement of future teaching, research and professional development. Attention is paid to the place of comparative and international education (CIE)-past and present-in teacher education, in postgraduate studies, and in the realms of policy and practice, theory and research. Consideration is first given to the nature and history of CIE, to its initial contributions to the field of education in the UK, and to its chief mechanisms and sites of production. Influential methodological and theoretical developments are examined, followed by an exploration of emergent questions, controversies and dilemmas that could benefit from sustained comparative analysis in the future. Conclusions consider implications for the place of CIE in the future of educational studies as a whole; for relations between and beyond the 'disciplines of education'; and for the development of sustainable research capacity in this field.

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Aim Habitat loss and climate change are two major drivers of biological diversity. Here we quantify how deforestation has already changed, and how future climate scenarios may change, environmental conditions within the highly disturbed Atlantic forests of Brazil. We also examine how environmental conditions have been altered within the range of selected bird species. Location Atlantic forests of south-eastern Brazil. Methods The historical distribution of 21 bird species was estimated using Maxent. After superimposing the present-day forest cover, we examined the environmental niches hypothesized to be occupied by these birds pre- and post-deforestation using environmental niche factor analysis (ENFA). ENFA was also used to compare conditions in the entire Atlantic forest ecosystem pre- and post-deforestation. The relative influence of land use and climate change on environmental conditions was examined using analysis of similarity and principal components analysis. Results Deforestation in the region has resulted in a decrease in suitable habitat of between 78% and 93% for the Atlantic forest birds included here. Further, Atlantic forest birds today experience generally wetter and less seasonal forest environments than they did historically. Models of future environmental conditions within forest remnants suggest generally warmer conditions and lower annual variation in rainfall due to greater precipitation in the driest quarter of the year. We found that deforestation resulted in a greater divergence of environmental conditions within Atlantic forests than that predicted by climate change. Main conclusions The changes in environmental conditions that have occurred with large-scale deforestation suggest that selective regimes may have shifted and, as a consequence, spatial patterns of intra-specific variation in morphology, behaviour and genes have probably been altered. Although the observed shifts in available environmental conditions resulting from deforestation are greater than those predicted by climate change, the latter will result in novel environments that exceed temperatures in any present-day climates and may lead to biotic attrition unless organisms can adapt to these warmer conditions. Conserving intra-specific diversity over the long term will require considering both how changes in the recent past have influenced contemporary populations and the impact of future environmental change.

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A new method for determining the temporal evolution of plasma rotation is reported in this work. The method is based upon the detection of two different portions of the spectral profile of a plasma impurity line, using a monochromator with two photomultipliers installed at the exit slits. The plasma rotation velocity is determined by the ratio of the two detected signals. The measured toroidal rotation velocities of C III (4647.4 angstrom) and C VI (5290.6 angstrom), at different radial positions in TCABR discharges, show good agreement, within experimental uncertainty, with previous results (Severo et al 2003 Nucl. Fusion 43 1047). In particular, they confirm that the plasma core rotates in the direction opposite to the plasma current, while near the plasma edge (r/a > 0.9) the rotation is in the same direction. This technique was also used to investigate the dependence of toroidal rotation on the poloidal position of gas puffing. The results show that there is no dependence for the plasma core, while for plasma edge (r/a > 0.9) some dependence is observed.

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The IR-spectrum of the isonicotinamide molecule (C(2)H(2)NC(3)H(2)CONH(2)) is studied by means of theoretical and experimental methods. For an appropriate representation of the molecular environment, Gaussian basis sets to the atoms of these molecule are built and then contracted (5s and 6s5p). For evaluation of the quality of contracted basis sets in molecular calculations, we have accomplished calculations of the total and the orbital (HOMO and HOMO-1) energies in the HF-Roothaan method for the molecule studied. The results obtained with the contracted basis sets [5s/6s5p] are compared to values obtained with our (21s/22s14p) basis sets and with those obtained with the D95, 6-31G, and 6-311G basis sets from literature. It was added one d polarization function in the [6s5p] contracted basis set for C ((3)P) atom, which was used in combination with the basis sets for H ((2)S), N ((4)S). and O((3)P) atoms to calculate the infrared spectrum of isonicotinamide. The calculations were performed at B3LYP level and were compared to corresponding experimental values also obtained in our laboratory. The theoretical results in comparison with the corresponding experimental values indicate a very good interpretation of the IR-spectrum and that the strategy of an appropriate representation of the molecular environment through the basis sets is an effective alternative to investigate vibrational theoretical properties of the nicotinamide molecule. (c) 2006 Published by Elsevier B.V.

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Includes bibliography

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Femtosecond lasers have been widely used in laser surgery as an instrument for contact-free tissue removal of hard dental, restorative materials, and osseous tissues, complementing conventional drilling or cutting tools. In order to obtain a laser system that provides an ablation efficiency comparable to mechanical instruments, the laser pulse rate must be maximal without causing thermal damage. The aim of this study was to compare the different morphological characteristics of the hard tissue after exposure to lasers operating in the femtosecond pulse regime. Two different kinds of samples were irradiated: dentin from human extracted teeth and bovine femur samples. Different procedures were applied, while paying special care to preserving the structures. The incubation factor S was calculated to be 0.788 +/- 0.004 for the bovine femur bone. These results indicate that the incubation effect is still substantial during the femtosecond laser ablation of hard tissues. The plasma-induced ablation has reduced side effects, i.e., we observe less thermal and mechanical damage when using a superficial femtosecond laser irradiation close to the threshold conditions. In the femtosecond regime, the morphology characteristics of the cavity were strongly influenced by the change of the effective number of pulses. (C) 2012 Society of Photo-Optical Instrumentation Engineers (SPIE). [DOI: 10.1117/1.JBO.17.4.048001]

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Agroindustrial residues are materials often rich in cellulose and hemicellulose. The use of these substrates for the microbial production of enzymes of industrial interest is mainly due to their high availability associated with their low cost. In this work, corncob (CCs) particles decomposed to soluble compounds (liquor) were incorporated in the microbial growth medium through autohydrolysis, as a strategy to increase and undervalue xylanase and beta-xylosidase production by Aspergillus terricola and Aspergillus ochraceus. The CCs autohydrolysis liquor produced at 200 A degrees C for 5, 15, 30 or 50 min was used as the sole carbon source or associated with untreated CC. The best condition for enzyme synthesis was observed with CCs submitted to 30 min of autohydrolysis. The enzymatic production with untreated CCs plus CC liquor was higher than with birchwood xylan for both microorganisms. A. terricola produced 750 total U of xylanase (144 h cultivation) and 30 total U of beta-xylosidase (96-168 h) with 0.75% untreated CCs and 6% CCs liquor, against 650 total U of xylanase and 2 total U of beta-xylosidase in xylan; A. ochraceus produced 605 total U of xylanase and 56 total U of beta-xylosidase (168 h cultivation) with 1% untreated CCs and 10% CCs liquor against 400 total U of xylanase and 38 total U of beta-xylosidase in xylan. These results indicate that the treatment of agroindustrial wastes through autohydrolysis can be a viable strategy in the production of high levels of xylanolytic enzymes.

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In this paper, we present the results of an experimental approach developed to study the macroscopic and microbiological alteration of bird and small mammal bones buried under a Cerrado biome. The first experiment evaluated the macroscopic alteration of cooked and fresh carcasses buried through the dry and rainy seasons. The second experiment analyzed the mycobiota associated to the decomposition of a complete bird that remained buried for almost a year. Results show that in tropical forest environments: 1) bone structure and pre-taphonomic factors determine its differential alteration by biochemical processes; 2) fungal populations associated to the decomposition of animal remains depend on soil chemistry and ecological dynamics; 3) even in a corrosive environment, bird bones are more capable of surviving to several mycological decomposition steps. (C) 2011 Elsevier Ltd. All rights reserved.

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Swiss lake-side settlements dating between 4300 and 800 BC were first recognized in the early 19th century and between 1854 and 1880 early research boomed due to the first scientific studies and the artificial lowering of lakes in Western Switzerland. In the 20th century underwater and wetland archaeology experienced an enormous surge not only because of large rescue excavations, due to extensive motorway construction projects but also due to the evolution of modern IT technology in the 1970s. For the first time huge quantities of ancient wooden structures could be dated by dendrochronology. This produced a quantum leap in the 150 years of pile-dwelling research. In 2011, the UNESCO World Heritage Committee recognized the outstanding universal value of these sites. This article presents an overview about Swiss pile-dwellings of the Neolithic and the Bronze Age and the results of two recent diploma works (case study Sutz-Lattrigen Haupstation innen and case study Seedorf Lobsigensee) as examples of research and cooperation between universities and government agencies for cultural heritage management.

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This report presents background material used by participants in a joint Ethiopian-Swiss study tour through the north-central highlands of Ethiopia. The main theme of the tour was 'land transformation and sustainable development'. The tour took place from 4-20 September 2006, starting in Addis Abeba and continuing through North Shewa, Wello, Gonder and Gojam. This report is a structured compilation of information gathered by MSc candidates and scientists from the University of Bern prior to the study tour, and supplemented with daily reports by all participants after the study tour was completed.

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Land-based aquaculture facilities often utilize additional bicarbonate sources such as commercial sea salts that are designed to boost alkalinity in order to buffer seawater against reductions in pH. Despite these preventative measures, many facilities are likely to face occasional reductions in pH and corresponding reductions in carbonate saturation states due to the accumulation of metabolic waste products. We investigated the impact of reduced carbonate saturation states (Omega Ca, Omega Ar) on embryonic developmental rates, larval developmental rates, and echinoplutei skeletal morphometrics in the common edible sea urchin Lytechinus variegatus under high alkalinity conditions. Commercial artificial seawater was bubbled with a mixture of air and CO2 gas to reduce the carbonate saturation state. Rates of embryonic and larval development were significantly delayed in both the low and extreme low carbonate saturation state groups relative to the control at a given time. Although symmetry of overall skeletal body lengths was not affected, allometric relationships were significantly different between treatment groups. Larvae reared under ambient conditions had significantly greater postoral arm and overall body lengths relative to body lengths than larvae grown under extreme low carbonate saturation state conditions, indicating that extreme changes in the carbonate system affected not only developmental rates but also larval skeletal shape. Reduced rates of embryonic development and delayed and altered larval skeletal growth are likely to negatively impact larval culturing of L. variegatus in land-based, intensive culture situations where calcite and aragonite saturation states are lowered by the accumulation of metabolic waste products.

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Planning and Comunity Development: Case Studies, presents the findings of the inter-university Seminar held on 28?29 July 2011 and organized by researchers from the Technical University of Madrid and the University of California, Berkeley, who were fortunate to have the presence of the renowned Professor John Friedmann. Professors, researchers and PhD students from our research groups presented their works as scientific communications that were enriched by the debate among the different researches who attended the Seminar. All of them appear in the picture below in front of the gate of Haviland Hall at UC Berkeley. This book analyses the concept of planning and its evolution so far, leading to the conceptualization of governance as an expression of the planning practice. It also studies the role of social capital and cooperation as tools for the community development. The conceptual analysis is complemented by the development of six case studies that put forward experiences of planning and community development carried out in diverse social and cultural contexts of Latin-America, Europe and North America. This publication comes after more than 20 years of work of the researchers that met at the seminar. Through their work in managing development initiatives, they have learned lessons and have contribute to shape their own body of teaching that develops and analyses the role of planning in public domain to promote community development. This knowledge is synthesized in the model Planning as Working With People, that shows that development is not effective unless is promoted in continuous collaboration with all the actors involved in the process.