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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.
71

Software Licensing in Cloud Computing : A CASE STUDY ABOUT RELATIONSHIPS FROM A CLOUD SERVICE PROVIDER’S PERSPECTIVE

Kabir, Sanzida January 2015 (has links)
One of the most important attribute a cloud service provider (CSP) offers their customers through their cloud services is scalability. Scalability gives customers the ability to vary the amount of capacity when required. A cloud service can be divided in three service layers, Infrastructure-as-a-Service (IaaS), Platform-as-a-Service (PaaS) and Software-as-a-Service (SaaS). Scalability of a certain service depends on software licenses on these layers. When a customer wants to increase the capacity it will be determined by the CSP's licenses bought from its suppliers in advance. If a CSP scales up more than what was agreed on, then there is a risk that the CSP needs to pay a penalty fee to the supplier. If the CSP invests in too many licenses that does not get utilized, then it will be an investment loss. A second challenge with software licensing is when a customer outsources their applications to the CSP’s platform. As each application comes with a set of licenses, there is a certain level of scalability that cannot be exceeded. If a customer wants the CSP scale up more than usual for an application then the customer need to inform the vendors. However, a common misunderstanding is that the customer expects the CSP to notify the vendor. Then there is a risk that the vendor never gets notified and the customer is in danger of paying a penalty fee. This in turn hurts the CSP’s relationship with the customer. The recommendation to the CSP under study is to create a successful customer relationship management (CRM) and a supplier relationship management (SRM). By creating a CRM with the customer will minimize the occurring misunderstandings and highlight the responsibilities when a customer outsources an application to the CSP. By creating a SRM with the supplier will help the CSP to maintain a flexible paying method that they have with a certain supplier. Furthermore, it will set an example to the remaining suppliers to change their inflexible paying method. By achieving a flexible payment method with the suppliers will make it easier for the CSP to find equilibrium between scalability and licenses. / Ett av de viktigaste attributen en molnleverantör (CSP) erbjuder sina kunder genom sina molntjänster är skalbarhet. Skalbarheten ger kunden möjligheten att variera mängden kapacitet efter behov. En molntjänst kan delas in i tre serviceskikter, Infrastruktur-as-a-Service (IaaS), Platform-as-a-Service (PaaS) och Software-as-a-Service (SaaS). Skalbarheten av en viss service beror på mjukvarulicenser på dessa skikt. När en kund vill öka kapaciteten bestäms detta av CSP:s förhandsköpta licenser från sina leverantörer. Om en CSP skalar upp mer än vad som avtalats, finns det en risk att CSP:n måste betala en straffavgift till leverantören. Investerar CSP i alltför många licenser som inte utnyttjas, blir det en investeringsförlust. En annan utmaning med mjukvarulicenser uppstår när en kund lägger ut sina applikationer på CSP:s plattform. Eftersom varje applikation levereras med en uppsättning av licenser, finns det en bestämd nivå av skalbarhet som inte kan överskridas. Om en kund vill att CSP:n ska skala upp mer än vanligt för en applikation, måste kunden informera applikationsförsäljaren själv. Dock sker det en missuppfattning då kunden förväntar sig att CSP:n ska meddela säljaren om detta. Det finns en risk att säljaren aldrig blir informerad och kunden hamnar i stor risk för att betala en straffavgift. Detta i sin tur skadar CSP:s relation med kunden. Rekommendationen till CSP:n är att skapa en framgångsrik kundrelationshantering (CRM) och leverantörrelationshantering (SRM). Genom att skapa en CRM med kunden kan förekommande missförstånd minimeras och belysa ansvarsområden som råder när en kund lägger ut sin applikation hos CSP:n. Genom att skapa en SRM med leverantörerna kommer det att hjälpa CSP:n att upprätthålla en flexibel betalmetod som de har med en viss leverantör. Dessutom kommer det att vara ett föredöme för de övriga leverantörerna att ändra sin icke flexibla betalningsmetod. Genom att uppnå en mer flexibel betalningsmetod med leverantörerna kommer det att bli enklare för en CSP att hitta en balans mellan skalbarhet och licenser.
72

Using KPIs in decision-making tools in the construction industry

Hedin, Nathalie, Zander, Adrian January 2019 (has links)
The construction industry has a great opportunity to streamline its operations even more by making greater use of the digital revolution. The industry today uses a lot of manual data management and analysis to get an overview of the business and to make decisions. This can be a time-consuming process that could be made more efficient through Business Intelligence (BI). BI is a technology that automatically, with the help of selected Key Performance Indicators (KPIs), shows the current status of how a business performs. This can allow managers and executives to make decisions easier and faster.This study examines which KPIs that are of common interest to companies and organizations in the construction industry as well as how these KPIs can be presented to the end users of a BI application. To investigate this, data is collected through literature studies and interviews, which results in a list of common KPIs for the industry. From this common list, a number of KPIs are selected to be visually represented.An analysis of the results, indicates that KPIs are of different importance and relevance depending on which sector of the construction industry the interviewee belongs to. There also appears to be sector-specific KPIs and the common list suggests that the profit margin is of great importance throughout the whole industry. KPIs can be represented in different types of charts and diagrams, depending on the purpose they hold, and should be designed so that they are intuitive and easy to understand. / Bygg- och hantverksbranschen har stor möjlighet att effektivisera sin verksamhet ännu mer genom att i större utsträckning utnyttja den digitaliserade utvecklingen. Branschen använder idag mycket manuell datahantering och manuell dataanalys för att få en överblick över verksamheten och ta beslut. Detta kan vara en tidskrävande process, som skulle kunna effektiviseras ytterligare genom Business Intelligence (BI). BI är en teknologi som automatiskt, med hjälp av valda nyckeltal (KPI:er), visar aktuell status på hur en verksamhet presterar. Detta kan göra att beslutsfattare kan fatta beslut enklare och snabbare.Denna studie undersöker vilka nyckeltal som är av gemensamt intresse för företag och organisationer i byggoch hantverksbranschen samt hur dessa nyckeltal kan presenteras för slutanvändarna av en BI-applikation. För att ta reda på detta samlas data in genom litteraturstudier och intervjuer, vilket resulterar i en lista över gemensamma KPI:er i branchen. Ur denna lista handplockas ett antal nyckeltal ut för att representeras visuellt.En analys av resultaten indikerar att nyckeltal är av olika vikt och relevans, beroende på vilken sektortillhörighet av byggoch hantverksbranschen den intervjuade tillhör. Det verkar även finnas sektorspecifika KPI:er samt att listan med de branchgemensamma nyckeltalen antyder att vinstmarginal är av stor vikt. KPI:er kan representeras i olika typer av diagram beroende på vilket syfte de innehar och bör designas så att de är intuitiva och lättförståeliga.
73

City and regional planning software in context : a rating framework for Planning Support Systems

Phelan, Chad Maclay 17 August 2010 (has links)
The difficulty of projecting ecological impacts, as well as the increasing familiarity of planners with Geographical Information Systems and other software technology has led to an increase in the use of Planning Support Systems (PSS) by city and regional planners. Due to their newness and rapid development, there is, of yet, a lack of a comprehensive peer-reviewed literature on the design and implementation of these systems. This thesis proposes and applies a rating framework for PSS in order to facilitate accessibility to and critical investigation of PSS. The rating framework’s criteria are based on the “seven sins” of comprehensive land use models identified by Douglass Lee’s 1973 article “Requiem for Large-Scale Models." / text
74

Diplolaimella dievengatensis (Nematoda: Monhysteridae) as model organism in ecotoxicity assay / Diplolaimella dievengatensis (Nematoda: Monhysteridae) como organismo modelo em ensaios de ecotoxicidade

Oliveira, Nilvea Ramalho de 25 September 2017 (has links)
Free-living marine nematodes are the most ubiquitous, abundant and diverse meiofaunal component of benthic communities. These are excellent model organisms, due to its short life span, wide availability and feasibility to cultivate with minimum laboratory facilities. In this study, a population of Diplolaimella dievengatensis Jacobs 1991 (Nematoda, Monhysteridae) from the relatively Pristine estuary of the Guaratuba River in São Paulo, Brazil was isolated and cultivated. The goals were; i- to apply an integrative taxonomic approach in order to compare this population from Brazil with another from the species type-locality in the Belgian Coast, with regard to morphological, life-cycle and the 18S gene of the rDNA molecular data; and ii- to compare, at the light of life history theory, the responses of life history parameters such as; fecundity, growth and survivorship of D. dievengatensis (here as a slower species) and Litoditis marina (Bastian, 1865) (Nematoda, Rhabditidae) (as a faster species) under sublethal exposition to the sodium dodecyl sulfate (SDS) surfactant. The population from Brazil was similar to that from Belgium coast in all parameters. Although morphometric analyses considered the Brazilian D. dievengatensis isometrically larger than the Belgian population regarding some characters, the presence of all diagnostic characters confirmed the similarity of both species. The life-cycle, hatching time, final body length, and biomass parameters were similar in both populations, in which females were larger than males. The population growth, measured as intrinsic rate of natural increase was slightly higher for the D. dievengatensis from Brazil (rm=0.41), than the European population (rm =0.348). Molecular comparison on Genbank showed 99.4% of similarity between both populations, indicating therefore, that D. dievengatensis from Brazil is similar to those from Belgium. In the chapter ii, both species responded differently to SDS exposition. Growth and reproduction rate of D. dievengatensis surprisingly were enhanced at low and intermediate concentrations of SDS (0.001 and 0.003%), while for L. marina these parameters were reduced in all SDS concentrations tested (0.001, 0.003 and 0.006%). The SDS did not affect the survivorship of adults of the slower specie. On the other hand, survivorship of adults of the fast species was significantly affected by SDS and this effect was dependent on adult gender, with reduced rates of males exposed to 0.006% SDS. Although both species are located nearby along the fast-slow continuum, they responded distinctly to of the toxic SDS effect. Effects over L. marina met the trend of faster species in allocating fewer investments in defenses against physiological injuries and on their own somatic maintenance. We propose that the apparent lower resistance of this faster species under stress at the individual level is balanced by their higher reproductive rates, conferring higher resilience to this species at the population level. Finally, it was demonstrated that the marine nematode D. dievengatensis is an important native model organism which can be used in a wide range of studies and experimental tests. Identifying and understanding differential effects of stress in the context of life-history theory is an important aspect which enhanced our understanding about the threats posed by anthropogenic activities on natural communities / Nematodas marinhos de vida livre são o mais onipresentes, abundantes e diversos componentes da meiofauna em comunidades bênticas. São excelentes organismos modelo devido a seu curto ciclo de vida, ampla disponibilidade e viabilidade de cultivo com mínima estrutura laboratorial. Neste estudo, uma população de Diplolaimella dievengatensis Jacobs 1991 (Nematoda, Monhysteridae) do estuário relativamente prístino do rio Guaratuba, São Paulo, Brasil foi isolada e cultivada. Os objetivos foram: ii- aplicar uma abordagem taxonômica integrativa a fim de comparar esta população do Brasil com outra da localidade tipo dessa espécie, da costa da Bélgica, com relação à dados morfológicos, do ciclo de vida e molecular do gene 18S do rDNA; e ii-comparar, à luz da teoria da historia de vida, repostas de parâmetros do ciclo de vida tais como: fecundidade, crescimento e sobrevivência de D. dievengatensis (aqui como espécies mais lenta) e Litoditis marina (Bastian, 1865) (Nematoda, Rhabditidae) (como espécie rápida) sob exposição subletal ao surfactante dodecil sulfato de sódio (DSS) . A população do Brasil foi similar a da costa da Bélgica em todos os parâmetros. Embora analises morfométricas consideraram D. dievengatensis do Brasil isometricamente maior que a população belga em relação em algumas características, a presença de todos os caracteres diagnósticos confirmaram a similaridade de ambas as espécies. Os parâmetros de ciclo de vida, tempo de eclosão, comprimento corporal final e biomassa foram similares em ambas as populações, nas quais fêmeas foram maiores que machos. Crescimento populacional, mensurado como taxa intrínseca de crescimento natural foi ligeiramente mais alta para D. dievengatensisdo Brasil (rm=0.41), que para a população europeia (rm=0.348). Comparações moleculares no Genbank mostraram 99.4% de similaridade entre ambas populações, indicando portanto que a população do Brasil é similar a D. dievengatensis belga. No capítulo ii, ambas as espécies responderam distintamente a exposição ao SDS. Supreendentemente as taxas de crescimento e de reprodução de D. dievengatensis foram incrementadas sob concentrações mais baixas e intermediárias (0.001 e 0.003%), enquanto para L. marina esses parâmetros foram reduzidos em todas as concentrações de DSS testadas (0.001, 0.003 e 0.006%). O DSS não afetou a sobrevivência de adultos da espécie mais lenta. Por outro lado, a sobrevivência de adultos da espécie mais rápida foi significativamente afetada pelo SDS e esse efeito foi dependente do sexo, com taxas reduzidas em machos expostos a 0.006 % de DSS. Embora ambas as espécies estejam proximamente dispostas ao longo do gradiente \"rápido-lento\", elas responderam diferentemente ao efeito tóxico do DSS. Efeitos sobre L marina se enquadram no padrão de espécies mais rápidas ao alocar menores investimentos para as defesas contra danos fisiológicos e para sua própria manutenção somática. Nós propomos que a aparente menor resistência desta espécie rápida sob estresse ao nível individual é balanceada por suas altas taxas reprodutivas, conferindo mais alta resiliência a essa espécie ao nível populacional. Por fim, foi demonstrado que D. dievengatensis é um importante organismo modelo nativo que pode ser usado em uma ampla diversidade estudos e testes experimentais. Identificar e compreender diferentes efeitos do estresse dentro do contexto da teoria da história de vida é um aspecto importante, o qual tem aumentado nosso conhecimento sobre as ameaças de atividades antropogênicas sobre comunidades naturais
75

State-Space Approaches to Ultra-Wideband Doppler Processing

Holl, Jr., David J. 03 May 2007 (has links)
National security needs dictate the development of new radar systems capable of identifying and tracking exoatmospheric threats to aid our defense. These new radar systems feature reduced noise floors, electronic beam steering, and ultra-wide bandwidths, all of which facilitate threat discrimination. However, in order to identify missile attributes such as RF reflectivity, distance, and velocity, many existing processing algorithms rely upon narrow bandwidth assumptions that break down with increased signal bandwidth. We present a fresh investigation into these algorithms for removing bandwidth limitations and propose novel state-space and direct-data factoring formulations such as * the multidimensional extension to the Eigensystem Realization Algorithm, * employing state-space models in place of interpolation to obtain a form which admits a separation and isolation of solution components, * and side-stepping the joint diagonalization of state transition matrices, which commonly plagues methods like multidimensional ESPRIT. We then benchmark our approaches and relate the outcomes to the Cramer-Rao bound for the case of one and two adjacent reflectors to validate their conceptual design and identify those techniques that compare favorably to or improve upon existing practices.
76

Rapid Frequency Estimation

Koski, Antti E. 28 March 2006 (has links)
Frequency estimation plays an important role in many digital signal processing applications. Many areas have benefited from the discovery of the Fast Fourier Transform (FFT) decades ago and from the relatively recent advances in modern spectral estimation techniques within the last few decades. As processor and programmable logic technologies advance, unconventional methods for rapid frequency estimation in white Gaussian noise should be considered for real time applications. In this thesis, a practical hardware implementation that combines two known frequency estimation techniques is presented, implemented, and characterized. The combined implementation, using the well known FFT and a less well known modern spectral analysis method known as the Direct State Space (DSS) algorithm, is used to demonstrate and promote application of modern spectral methods in various real time applications, including Electronic Counter Measure (ECM) techniques.
77

How to Leverage Text Data in a Decision Support System? : A Solution Based on Machine Learning and Qualitative Analysis Methods

Yu, Shuren January 2019 (has links)
In the big data context, the growing volume of textual data presents challenges for traditional structured data-based decision support systems (DSS). DSS based on structured data is difficult to process the semantic information of text data. To meet the challenge, this thesis proposes a solution for the Decision Support System (DSS) based on machine Learning and qualitative analysis, namely TLE-DSS. TLE-DSS refers to three critical analytical modules: Thematic Analysis (TA), Latent Dirichlet Allocation (LDA)and Evolutionary Grounded Theory (EGT). To better understand the operation mechanism of TLE-DSS, this thesis used an experimental case to explain how to make decisions through TLE-DSS. Additionally, during the data analysis of the experimental case, by calculating the difference of perplexity of different models to compare similarities, this thesis proposed a solution to determine the optimal number of topics in LDA. Meanwhile, by using LDAvis, a model with the optimal number of topics was visualized. Moreover, the thesis also expounded the principle and application value of EGT. In the last part, this thesis discussed the challenges and potential ethical issues that TLE-DSS still faces.
78

Agencification in the Australian Public Service: the case of Centrelink

Rowlands, David, n/a January 2002 (has links)
Agencification-the creation of autonomous agencies within the public service-has been occurring in many jurisdictions. It has usually had a rationale of improving the way in which government works. Generally, agencies are expected to provide more flexible, performance-oriented, responsive public services. The purpose of this work is to examine a particular example of agencification in the Australian Public Service (APS) and to compare it analytically with similar occurrences elsewhere. Specifically, it will examine the splitting of the former Department of Social Security (DSS) into two separate organisations, a policy department and a service delivery agency operating under a purchaser-provider arrangement, Centrelink. It will do this in the context of theories of agencification and of practical experience of agencification elsewhere. It will analyse why agencification has happened in this case and what the experience has shown, focusing on the role, governance, accountability and prospects for the new arrangements. This, the most prominent and substantial case of agencification in the Australian government, will be compared with the agencification experience reported in other jurisdictions-the United Kingdom and New Zealand. It will address why Centrelink came about, what the outcome has been of the change in institutional arrangements, and what the likely future is of the Centrelink arrangements. It will show that, when examined closely, the mechanisms bringing about agencification have been diverse. However, there are parallels in the experience. This leads to a conclusion that the current Centrelink arrangements are not stable in the long term, and some aspects-such as the purchaser-provider arrangement - should be set aside.
79

Efeitos do fenol e 4-clorofenol sobre o desenvolvimento embriolarval de Echinometra Lucunter (Linnaeus, 1758): avaliação dessas substâncias como referência.

Bonfim, Cíntia Levita Lins do January 2005 (has links)
p. 1-82 / Submitted by Santiago Fabio (fabio.ssantiago@hotmail.com) on 2013-04-10T20:04:49Z No. of bitstreams: 1 Dissert seg01.pdf: 499245 bytes, checksum: 0655b17411b2a8d56e0ae1742341678e (MD5) / Rejected by Alda Lima da Silva(sivalda@ufba.br), reason: Corrigir Instituto de Biologia on 2013-04-15T20:24:41Z (GMT) / Submitted by Santiago Fabio (fabio.ssantiago@hotmail.com) on 2013-04-23T20:51:38Z No. of bitstreams: 1 Dissert seg01.pdf: 499245 bytes, checksum: 0655b17411b2a8d56e0ae1742341678e (MD5) / Approved for entry into archive by Alda Lima da Silva(sivalda@ufba.br) on 2013-05-03T20:58:38Z (GMT) No. of bitstreams: 1 Dissert seg01.pdf: 499245 bytes, checksum: 0655b17411b2a8d56e0ae1742341678e (MD5) / Made available in DSpace on 2013-05-03T20:58:38Z (GMT). No. of bitstreams: 1 Dissert seg01.pdf: 499245 bytes, checksum: 0655b17411b2a8d56e0ae1742341678e (MD5) Previous issue date: 2005 / Inúmeras substâncias químicas que compõem os produtos manufaturados e estão presentes nos efluentes de origem industrial, são corriqueiramente dispostas no meio ambiente através do carreamento para corpos d´água naturais. Os testes de toxicidade aquática são empregados com o intuito de avaliar o efeito destes agentes químicos nos organismos, fornecendo assim uma abordagem ecológica complementar às analises químicas normalmente empregadas. Para serem validados os testes ecotoxicológicos precisam ser realizados seguindo protocolos específicos e fazerem uso de substâncias de referência, que são químicos de efeito conhecido sobre os organismos de maneira a atestarem a confiabilidade dos resultados obtidos. O objetivo deste trabalho foi avaliar a utilização das substâncias orgânicas Fenol e 4-Clorofenol, como alternativas para referência em testes ecotoxicológicos com embriões do ouriço-do-mar Echinometra lucunter. Para isto, quinze testes crônicos de curta duração foram conduzidos para cada substância investigada, mais o Dodecil Sulfato de Sódio (DSS), que foi utilizado como controle positivo. Os valores de CE50-36h encontrados variaram de 125,88 a 143,84 mg/L para o Fenol e de 16,90 a 26,31 mg/L para o 4-Clorofenol. A concentração de efeito alternativo foi determinada com base na DMS crítica. O nível equivalente à concentração estimada de efeito crônico foi CE10. A partir de tal concentração é possível observar efeitos deletérios significativos na população do organismo-teste. O valor médio de CE10-36h encontrado para o Fenol foi de 36,63 mg/L e para o 4- Clorofenol foi de 4,58 mg/L. Os coeficientes de variação dos resultados obtidos indicaram que os valores encontrados para o Fenol no nível de efeito de 50% apresentam maior precisão analítica (4,04%), enquanto que no nível de efeito alternativo, o 4-Clorofenol apresentou maior precisão dentre as substâncias utilizadas (27,98%). A plotagem em carta-controle, dos resultados obtidos com os testes utilizando o DSS, que foram realizados em paralelo à outras substâncias, atestaram a saúde dos organismos utilizados e a obtenção de resultados confiáveis nos experimentos conduzidos. Embriões de E. lucunter são mais sensíveis ao 4- Clorofenol do que ao Fenol, uma vez que sob as mesmas concentrações, o valor de CE50-36h obtido para o Fenol foi mais alto que o obtido para o 4-Clorofenol. Aliadas às características peculiares a cada substância, o 4-Clorofenol apresentou-se como mais indicado para a utilização como referência em testes ecotoxicológicos com embriões de E. lucunter. / Salvador
80

Diplolaimella dievengatensis (Nematoda: Monhysteridae) as model organism in ecotoxicity assay / Diplolaimella dievengatensis (Nematoda: Monhysteridae) como organismo modelo em ensaios de ecotoxicidade

Nilvea Ramalho de Oliveira 25 September 2017 (has links)
Free-living marine nematodes are the most ubiquitous, abundant and diverse meiofaunal component of benthic communities. These are excellent model organisms, due to its short life span, wide availability and feasibility to cultivate with minimum laboratory facilities. In this study, a population of Diplolaimella dievengatensis Jacobs 1991 (Nematoda, Monhysteridae) from the relatively Pristine estuary of the Guaratuba River in São Paulo, Brazil was isolated and cultivated. The goals were; i- to apply an integrative taxonomic approach in order to compare this population from Brazil with another from the species type-locality in the Belgian Coast, with regard to morphological, life-cycle and the 18S gene of the rDNA molecular data; and ii- to compare, at the light of life history theory, the responses of life history parameters such as; fecundity, growth and survivorship of D. dievengatensis (here as a slower species) and Litoditis marina (Bastian, 1865) (Nematoda, Rhabditidae) (as a faster species) under sublethal exposition to the sodium dodecyl sulfate (SDS) surfactant. The population from Brazil was similar to that from Belgium coast in all parameters. Although morphometric analyses considered the Brazilian D. dievengatensis isometrically larger than the Belgian population regarding some characters, the presence of all diagnostic characters confirmed the similarity of both species. The life-cycle, hatching time, final body length, and biomass parameters were similar in both populations, in which females were larger than males. The population growth, measured as intrinsic rate of natural increase was slightly higher for the D. dievengatensis from Brazil (rm=0.41), than the European population (rm =0.348). Molecular comparison on Genbank showed 99.4% of similarity between both populations, indicating therefore, that D. dievengatensis from Brazil is similar to those from Belgium. In the chapter ii, both species responded differently to SDS exposition. Growth and reproduction rate of D. dievengatensis surprisingly were enhanced at low and intermediate concentrations of SDS (0.001 and 0.003%), while for L. marina these parameters were reduced in all SDS concentrations tested (0.001, 0.003 and 0.006%). The SDS did not affect the survivorship of adults of the slower specie. On the other hand, survivorship of adults of the fast species was significantly affected by SDS and this effect was dependent on adult gender, with reduced rates of males exposed to 0.006% SDS. Although both species are located nearby along the fast-slow continuum, they responded distinctly to of the toxic SDS effect. Effects over L. marina met the trend of faster species in allocating fewer investments in defenses against physiological injuries and on their own somatic maintenance. We propose that the apparent lower resistance of this faster species under stress at the individual level is balanced by their higher reproductive rates, conferring higher resilience to this species at the population level. Finally, it was demonstrated that the marine nematode D. dievengatensis is an important native model organism which can be used in a wide range of studies and experimental tests. Identifying and understanding differential effects of stress in the context of life-history theory is an important aspect which enhanced our understanding about the threats posed by anthropogenic activities on natural communities / Nematodas marinhos de vida livre são o mais onipresentes, abundantes e diversos componentes da meiofauna em comunidades bênticas. São excelentes organismos modelo devido a seu curto ciclo de vida, ampla disponibilidade e viabilidade de cultivo com mínima estrutura laboratorial. Neste estudo, uma população de Diplolaimella dievengatensis Jacobs 1991 (Nematoda, Monhysteridae) do estuário relativamente prístino do rio Guaratuba, São Paulo, Brasil foi isolada e cultivada. Os objetivos foram: ii- aplicar uma abordagem taxonômica integrativa a fim de comparar esta população do Brasil com outra da localidade tipo dessa espécie, da costa da Bélgica, com relação à dados morfológicos, do ciclo de vida e molecular do gene 18S do rDNA; e ii-comparar, à luz da teoria da historia de vida, repostas de parâmetros do ciclo de vida tais como: fecundidade, crescimento e sobrevivência de D. dievengatensis (aqui como espécies mais lenta) e Litoditis marina (Bastian, 1865) (Nematoda, Rhabditidae) (como espécie rápida) sob exposição subletal ao surfactante dodecil sulfato de sódio (DSS) . A população do Brasil foi similar a da costa da Bélgica em todos os parâmetros. Embora analises morfométricas consideraram D. dievengatensis do Brasil isometricamente maior que a população belga em relação em algumas características, a presença de todos os caracteres diagnósticos confirmaram a similaridade de ambas as espécies. Os parâmetros de ciclo de vida, tempo de eclosão, comprimento corporal final e biomassa foram similares em ambas as populações, nas quais fêmeas foram maiores que machos. Crescimento populacional, mensurado como taxa intrínseca de crescimento natural foi ligeiramente mais alta para D. dievengatensisdo Brasil (rm=0.41), que para a população europeia (rm=0.348). Comparações moleculares no Genbank mostraram 99.4% de similaridade entre ambas populações, indicando portanto que a população do Brasil é similar a D. dievengatensis belga. No capítulo ii, ambas as espécies responderam distintamente a exposição ao SDS. Supreendentemente as taxas de crescimento e de reprodução de D. dievengatensis foram incrementadas sob concentrações mais baixas e intermediárias (0.001 e 0.003%), enquanto para L. marina esses parâmetros foram reduzidos em todas as concentrações de DSS testadas (0.001, 0.003 e 0.006%). O DSS não afetou a sobrevivência de adultos da espécie mais lenta. Por outro lado, a sobrevivência de adultos da espécie mais rápida foi significativamente afetada pelo SDS e esse efeito foi dependente do sexo, com taxas reduzidas em machos expostos a 0.006 % de DSS. Embora ambas as espécies estejam proximamente dispostas ao longo do gradiente \"rápido-lento\", elas responderam diferentemente ao efeito tóxico do DSS. Efeitos sobre L marina se enquadram no padrão de espécies mais rápidas ao alocar menores investimentos para as defesas contra danos fisiológicos e para sua própria manutenção somática. Nós propomos que a aparente menor resistência desta espécie rápida sob estresse ao nível individual é balanceada por suas altas taxas reprodutivas, conferindo mais alta resiliência a essa espécie ao nível populacional. Por fim, foi demonstrado que D. dievengatensis é um importante organismo modelo nativo que pode ser usado em uma ampla diversidade estudos e testes experimentais. Identificar e compreender diferentes efeitos do estresse dentro do contexto da teoria da história de vida é um aspecto importante, o qual tem aumentado nosso conhecimento sobre as ameaças de atividades antropogênicas sobre comunidades naturais

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