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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Remoção biológica simultânea de fósforo e nitrogênio de esgoto sanitário em reatores sequenciais em batelada

FERREIRA, Ana Linda Tiago Soares 30 June 2014 (has links)
Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-07-26T14:51:03Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Ferreira, Ana Linda (TESE) EngCivil14.pdf: 3085122 bytes, checksum: d948f8fbcdf65b938ccf579d975895d1 (MD5) / Made available in DSpace on 2016-07-26T14:51:03Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Ferreira, Ana Linda (TESE) EngCivil14.pdf: 3085122 bytes, checksum: d948f8fbcdf65b938ccf579d975895d1 (MD5) Previous issue date: 2014-06-30 / CAPEs / O aporte excessivo de nutrientes como o fósforo e o nitrogênio são uma das principais causas da eutrofização das águas, um grave problema ambiental resultante de descargas de efluentes domésticos e industriais, bem como do uso intensivo de fertilizantes em campos agrícolas. Não obstante, é preocupante o facto das reservas de fósforo estarem a diminuir mundialmente. Este trabalho objetiva a remoção simultânea de fósforo e nitrogênio e o estudo das condições de funcionamento para o estabelecimento de uma comunidade específica de microrganismos para esse fim, tratando efluente real de origem domestica. Para isso foram instalados dois reatores em batelada sequencial com 140L de volume útil na ETE Mangueira em Recife/PE. Os resultados revelam que a adição de propionato para o enriquecimento do lodo melhora a sua sedimentabilidade enquanto que a adição de acetato favorece o desenvolvimento de organismos filamentosos. A aplicação de aeração continua inibiu a nitrificação e desnitrificação simultânea, enquanto que a aeração escalonada favoreceu esse processo. Dependendo da forma de como se procede a aeração do reator é possível reduzir a fonte de carbono na fase anóxica e também o TDH global de operação do reator. Foi possível remover DQO com eficiência acima de 90%, além de remover nitrogênio e fósforo em reatores RSB, mesmo com esgotos diluídos. A remoção de fósforo ocorreu através do mecanismo de remoção biológica de fósforo avançado (EBPR). / Excessive discharges of nutrients like phosphorus and nitrogen are one of the main causes of water eutrophication, a serious environmental problem resulting mainly from discharges of domestic and industrial effluents as well as the intensive use of fertilizers in agricultural fields. Nevertheless, it is being motif of concern that phosphorus reserves are declining worldwide. This work aims for simultaneous removal of phosphorus and nitrogen and the study of the operating conditions for the establishment of a specific community of microorganisms for this purpose, treating real domestic wastewater. For this two reactors were installed in sequencing batch with 140L working volume in ETE Mangueira in Recife / PE. The results show that the addition of propionate to the enrichment of the sludge settle ability improves their while adding acetate favors the growth of filamentous organisms. The application of continued aeration inhibited simultaneous nitrification and denitrification (SND), while the stepped aeration favored this process. Depending on how one proceeds as aeration reactor is possible to reduce the carbon source in the anoxic phase and also the overall HRT of reactor operation. COD could be removed with efficiency above 90%, in addition to removing nitrogen and phosphorus in SBR reactors, even with diluted sewage. The phosphorus removal occurred through the mechanisms of Enhanced Biological Phosphorus Removal(EBPR).
82

ESTUDO TEÓRICO DE FULERENOS FUNCIONALIZADOS INTERAGINDO COM TEMOZOLAMIDA

Vendrame, Laura Fernanda Osmari 31 March 2015 (has links)
Submitted by MARCIA ROVADOSCHI (marciar@unifra.br) on 2018-08-16T20:05:43Z No. of bitstreams: 2 Dissertação_LauraFernandaOsmariVendrame.pdf: 3061643 bytes, checksum: d06cb3bc35f9d2bedf0c39b9c8e35276 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-08-16T20:05:43Z (GMT). No. of bitstreams: 2 Dissertação_LauraFernandaOsmariVendrame.pdf: 3061643 bytes, checksum: d06cb3bc35f9d2bedf0c39b9c8e35276 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2015-03-31 / The use of C60 fullerenes, functionalized or in pristine form, as chemical and biological sensors has become a large field of study and application High stability and low chemical reactivity of these nanostructures provide some difficulties in studying the chemical and physical properties. These difficulties can be overcome through the functionalization process. The purpose of this work is to evaluate through abs initio calculations the structural and electronic properties of the temozolamide molecule interacting with functionalized fullerenes. This drug is very important for the treatment of brain tumors. This study is based on the density functional theory, using the SIESTA computational code. First of all, it was evaluated the isolated functionalized fullerenes behavior, as well as the temozolamide molecule. Subsequently, it was studied the interaction of functionalized fullerenes with temozolamide in order to understand the energetic and structural properties of these structures to support the use of these nanomaterials in future biomedical applications. From the results it is possible to observe the depending on the studied configuration, the binding energy values are not the same. It was found a weak interaction for all functionalized C60 interacting with temozolamide through physical adsorption, with values between 0.43 eV and 1.02 eV for all stable configurations. An interaction through physical adsorption was also observed for themozolamide with pristine fullerenes, with energy value of 0.23 eV. Despite some high energy values, the distance in the interaction between the nearest atoms of the nanostructure and temozolomide does not represent chemical bonds. The interaction of the temozolamide drug with fullerenes is important for the future development of central nervous system nanodrugs improving the performance and slowing the elimination of the drug by the body. / O uso de fulerenos C60, funcionalizados ou na forma pura, como carreadores de fármacos tem se tornado um grande campo de estudo e aplicação. A alta estabilidade e baixa reatividade química destas nanoestruturas trazem algumas dificuldades de manipulação no estudo de suas propriedades químicas e físicas. Estas dificuldades podem ser superadas através do processo de funcionalização. O objetivo deste trabalho é avaliar, por meio de cálculos ab initio as propriedades estruturais e eletrônicas da molécula de temozolamida interagindo com fulerenos puros e funcionalizados. A temozolamida é um medicamento muito importante no tratamento de tumores cerebrais. Este estudo é baseado na teoria do funcional da densidade, utilizando o código computacional SIESTA. Primeiramente, estudamos os fulerenos funcionalizados isolados, bem como a molécula de temozolamida. Posteriormente, estudamos a interação do fulereno puro e funcionalizado, com a temozolamida a fim de compreender suas propriedades energéticas e estruturais. A partir dos resultados é possível observar que, dependendo da configuração estudada, os valores de energia de ligação não são os mesmos. Obtivemos uma interação fraca para todos os C60 funcionalizados interagindo com a temozolamida via adsorção física, com valores entre 0,43 eV e 1,02 eV para as configurações mais estáveis. Uma interação via adsorção física tambem foi observada para a interação da temozolamida com fulerenos puros, com energia de 0,23 eV Apesar de alguns valores altos de energia, a distância na interação entre os átomos mais próximos entre a nanoestrutura e a temozolamida e a baixa transferência de carga, não representam características de ligações covalentes. A interação da temozolamida com fulerenos, através da funcionalização, neste estudo, é importante para contribuir com o futuro desenvolvimento de nanomedicamentos do sistema nervoso central melhorando o desempenho e reatardando a eliminação do medicamento pelo organismo.
83

Topics on open economy macroeconomics : a stock-flow consistent approach / Topiques en macroéconomie des économies ouvertes : une approche stock-flux cohérente

Valdecantos Halporn, Sebastian 13 April 2015 (has links)
Cette thèse présente une série d'études théoriques partageant une méthodologie commune: l'utilisation des modèles stock-flux cohérents. Sur la base de l'échec de l'outil d'analyse économique traditionnel, les modèles DSGE, je tente de montrer quels sont les principaux inconvénients de ces modèles, qui comprennent à la fois des problèmes méthodologiques et l'omission de certains aspects de la réalité qui sont cruciales (par exemple, le rôle de la monnaie et des marchés financiers). Dans le premier chapitre de cette thèse je montre pourquoi les modèles stock-flux cohérents offrent un véhicule plus précis à la compréhension des économies modernes. Ces raisons, qui sont reliés à une préoccupation plus élevé avec le réalisme, la précision comptable et l'interaction entre les différents agents économiques et des institutions sociales, expliquent pourquoi les modèles stock-flux cohérents ont réussi à détecter les instabilités qui se accumulaient dans les années avant l'éclatement de la crise financière mondiale. Après avoir expliqué la motivation pour étudier la dynamique macroéconomique par des modèles stock-flux cohérents je présente trois chapitres dans lesquels ces modèles sont adaptés à l'étude de certains problèmes spécifiques du monde réel, qui ont été et sont toujours pertinentes et ont une place privilégiée dans le agenda politique. Dans le deuxième chapitre, je étudie certaines des différentes alternatives pour la réforme du système monétaire international qui ont été proposées depuis la fin de la Seconde Guerre mondiale. A partir d'un modèle qui décrit l'état actuel des choses, il est montré comment ce modèle peut être modifié afin d'examiner comment chacun des solutions alternatives pourraient fonctionner. Ces solutions comprennent des options qui ont été largement débattues depuis des décennies, comme l'introduction du DTS (la monnaie émise par le FMI) et le bancor (la monnaie internationale que Keynes a proposé, avec la création d'une chambre de compensation internationale). Après avoir construit les modèles, des exercices de simulation sont menées. Ces expériences montrent de quelle façon chaque solution pourrait offrir un meilleur environnement mondial pour le développement des relations économiques internationales. En particulier, il est constaté que la mise en place d'une chambre de compensation comme laquelle Keynes a proposé ne serait pas seulement avantageuse à réduire les déséquilibres mondiaux, mais aussi elle pourrait produire un haut niveau de demande effective dans une échelle mondiale... / His  thesis  presents  a  series  of  theoretical  studies  sharing  a  common  methodology:  the  use  of  stock-­‐flow consistent models. Based on the failure of the state of the art analytical tool of the mainstream, the so-­‐called DSGE models, I attempt to show what are the main drawbacks of these models, which include both methodological problems and the omission of some aspects of reality that are crucial (e.g., the role of money and financial markets). In the first chapter of this thesis I show  why  stock-­‐flow  consistent  models  offer  a  more  accurate  vehicle  to  the  understanding  of  modern economies. These reasons, which are connected to a higher concern with realism, accounting  accuracy  and  the  interaction  between  the  different  economic  agents  and  social  institutions, explain why stock-­‐flow consistent models have been successful in detecting the instabilities that were accumulating in the years before the outbreak of the global financial crisis...
84

Post-harvest floor changes and nitrogen mobilization in an Engelmann spruce-subalpine fir forest

David, Clive Addison January 1987 (has links)
Engelmann spruce-subalpine fir [Picea engelmannii Parry ex Engelm.-Abies lasiocarpa (Hook.) Nutt.] (ESSF) forests occupy large portions of western North America, and of British Columbia (B.C.) in particular. These areas represent a harsh environment for plant growth. The ESSF forests of B.C. have presented serious problems of regeneration following harvesting; several factors stimulated speculation as to whether N supply limitations were involved. This study was intended to highlight the post-harvest N dynamics of an ESSF forest, and the implications of the latter for silvicultural practices. Its general objectives included characterization of the post-harvest assart effect, and investigation of the N status and growth of advance regeneration. These were achieved by means of a comparative study of an age sequence of harvested sites. The assart effect lasted for at least eight years after harvesting, with a peak of change between years three and six. There were no major physical changes in the forest floor. Low C/N ratios between 19 and 32 were believed to have contributed to increased N availability. ESSF forests may have a generally higher level of N availability than previously supposed. The advance regeneration benefited from the assart effect. Nutrient uptake appeared to increase generally from at least three years after harvesting; increases of up to 78% were noted for N. There appeared to be no general macronutrient or micronutrient limitation to growth. However, evidence of S deficiencies was encountered in some trees. Moreover, the critical levels used for N may be in need of revision. A revised critical level of 1.40% for foliar N concentrations is proposed for subalpine fir advance regeneration. If this is accurate, regeneration may have been at least temporarily N-limited from year eight after harvesting. A more rigorous investigation of these possibilities is needed. The cutting method applied to the sites approximated a one-cut shelterwood method. The method as encountered in this study should not be considered a viable silvicultural option for similar ESSF forests. Its successful application would involve some degree of forest floor manipulation to improve seedbed conditions and soil microclimatic regimes. The findings of this study demonstrate that the environmental and biological characteristics of ESSF forests make high levels of planning and care a prerequisite for the success of silvicultural practices. The question of what comprises realistic growth and yield expectations of second-rotation stands in the ESSF zone needs to be addressed urgently. / Forestry, Faculty of / Graduate
85

Managing the implementation of the assessment policy in the senior certificate band

Maselesele, Maluleke Samuel 30 May 2011 (has links)
Educators in the basic education system are facing extreme challenges in assessing learners in general and in implementing assessment policy in particular. These challenges influence the pass rate, particularly in grade 12. The validity of the evidence of the learners’ performance depends on the quality and type of assessment tasks administered to those learners. Therefore, it was critical that those aspects, which pose challenges in the management of the assessment policy within the education system, be addressed by developing policies which would assist educators in managing assessment at school, since assessment forms an integral part of teaching and learning. Support programmes on policy implementation had to be developed for learners and for the training of educators, the implementation of which should improve the pass rate. These programmes had to include the conditions and roles of provincial and district education officers. A South African policy development model had to be developed to address the unique situation of developing such programmes. The introduction of the National Curriculum Statement (NCS) and the National Protocol on Recording and Reporting (NPRR) were some of the measures aimed at improving learner performance and assisting educators in implementing and managing assessment which is in line with national policy. An exploratory study, aimed at providing a broad framework on policy analysis, was used with the view to understand how the NCS and National Protocol for Recording and Reporting are managed. A proportional representative sample of 25% of the schools from the six clusters in the Mopani district formed part of this study. To ensure that the historically white, urban and rural schools were represented, an incidental biased sampling method was used. Data obtained from the questionnaire indicates that educators have knowledge of the various policies, acts and guidelines which should be used in assessing learners. However, some data indicates that some educators know about the existence of such policies, acts and guidelines but do not have knowledge of the content thereof. Data obtained from the interviews indicates that educators either know the content of policies or are only aware of them. Therefore, the lack of knowledge of policy content which regulates the practice of a policy has an influence on the teaching and assessing of learners. / Thesis (PhD)--University of Pretoria, 2011. / School of Public Management and Administration (SPMA) / unrestricted
86

Využití IT pro optimalizaci platebního styku / Usage of information technologies for optimalization of payment transactions

Kost, Tomáš January 2007 (has links)
This master's thesis analyses the problems concerning system of payments especially clearing credit transfers, bank statement of accounts and interconnection with the company’s information system. It proposes suitable ways of optimalization which in the upshot lead to a better exploitation of information technologies and simplification for the human operator.
87

Studium maternálně-fetálního mikrochimérismu APC s využitím MHCII/EGFP myšího modelu a clearovacích histologických technik / Study of the materno-fetal microchimerism of the APC using MHCII/EGFP mouse model and clearing histological techniques

Knížková, Karolina January 2020 (has links)
Microchimerism arises from the exchange of cells between genetically distinct individuals. The coexistence of genetically distinct cell populations within a single organism has possible effects on health and functioning of individuals immune systems, but the exact mechanisms of action are often not yet known. With the development of microscopic technologies and software for data analysis, the possibilities of detection and phenotyping of these rare cell populations are expanding. My intention in this work is to find maternal microchimerism in embryonic tissues (E13) and intestines of breastfed pups using MHCII/EGFP knock-in mouse model. Several different technologies potentially suitable for the detection of maternal microchimeric cells in offspring tissues (light sheet fluorescent microscopy - LSFM, virtual slide microscopy and flow cytometry) were selected. Advanced analysis of the obtained samples from the light sheet microscopy using the creation of a neural network was used here. The presence of maternal microchimerism was not demonstrated by flow cytometry. Using LSFM, image data were obtained from intestinal samples of suckling pups, which were processed by the neural network method. Data analysis of embryos (E13) obtained by the same method did not allow data analysis due to high...
88

Development and Application of Tools for the Characterization of the Optogenetics Stimulation of the Cochlea

Duque Afonso, Carlos Javier 29 August 2019 (has links)
No description available.
89

Revetment clearing, its influence on riparian mammal communities

Willis, Robert E. 01 January 1981 (has links)
Over 115 miles of rock revetment have been constructed in the Willamette Basin to protect river banks. This study examines the effect on riparian mammals of maintaining these revetments by vegetation and debris clearing. Differences between cleared and uncleared revetments were measured using a canopy coverage method of vegetation analysis; mammals were studied by trapping, by direct observation, and by noting such signs as scats, tracks, etc.
90

A Journey Through the World of Compression with IRS Contracts / En resa genom kompressionens värld med IRS kontrakt

Hjalmarsson, Karl January 2023 (has links)
By participating in the market a party buys and sells different types of contracts resulting in the collection of contracts growing. With a large collection of contracts come the hurdles of an increasing operational cost, a harder-to-manage order book, and an increase in counterparty risk. To combat these problems we set out to minimize the size and quantity of contracts by performing what is called a compression. We have looked into three different types of compression methods for interest rate swap contracts. One method is specialized for central clearing, Coupon Blending, and two methods for bilateral clearing, Closed Loops, and the Network Simplex Method. By using Monte Carlo Simulations, all three methods could be compared to one another to conclude the significant findings. The clear winner for centrally cleared contracts was Coupon Blending which could terminate over 92% of the contracts, and reduce the total absolute size of the contracts by over 75%. Network Simplex came in as a close second which could also reduce the total absolute size of the contracts by over 75% but only terminate 86%. Coupon Blending and Network Simplex, both had very similar accuracy in their compression. However, NetworkSimplex performed better at keeping the system’s total risk intact. For bilateral clearing, NetworkSimplex performed the best where the Closed Loops strategy was not an optimized approach. / Genom att delta i den finansiella marknaden köper och säljer en participant olika sorters kontrakt vilket resulterar i att samlingen av kontrakt växer. Med en ständigt växande samling av kontrakt skapas problem som, att kostnaden för hantering ökar, att orderbokens hantering blir svårare och en ökad risk för konkurs. För att undvika dessa problem kan man utföra kompression vilket är att försöka reducera kontrakten i antal och storlek. Vi har studerat tre olika typer av kompressionsstrategier för kompression av ränteswappar. Den första strategin är Coupon Blending som är specialiserad för central clearing medan de två andra, Closed Loops och Network Simplex Metoden är utvecklade för bilateral clearing. Genom att använda Monte Carlo Simuleringar på alla tre strategier kunde vi dra slutsatser kring deras egenskaper och effektivitet. Den bästa strategin var Coupon Blending som kunde terminera över 92% av alla kontrakt, och samtidigt reducera den totala absoluta storleken på kontrakten med 75%. Network Simplex presterade också bra och kunde reducera den totala absoluta storleken på kontrakten med 75% och terminera 86% av kontrakten. Coupon Blending och Network Simplex hade bägge en liknande noggrannhet, men Network Simplex var något bättre på att hålla systemets totala risk intakt. För bilateral clearing presterade Network Simplex bäst där Closed Loops strategin inte var tillräckligt optimerad.

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