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Propagation and Retention of Viscoelastic Surfactants in Carbonate CoresYu, Meng 2011 May 1900 (has links)
Viscoelastic surfactant have found numerous application in the oil fields as fracturing and matrix acidizing fluid additives in the recent years. They have the ability to form long worm-like micelles with the increase in pH and calcium concentration, which results in increasing the viscosity and elasticity of partially spent acids.
On one hand, concentration of surfactant in the fluids has profound effects on their performance downhole. Additionally, there is continuous debate in the industry on whether the gel generated by these surfactants causes formation damage, especially in dry gas wells. Therefore, being able to analyze the concentration of these surfactants in both live and spent acids is of great importance for production engineers who apply surfactant-based fluids in the oil fields. In the present work, a two-phase titration method was optimized for quantitative analysis of a carboxybetaine viscoelastic surfactant, and surfactant retention in calcite cores was quantitatively determined by two phase titration method and the benefits of using mutual solvents to break the surfactant gel formed inside the cores was assessed.
On the other hand, high temperatures and low pH are usually involved in surfactant applications. Surfactants are subjected to hydrolysis under such conditions due to the existence of a peptide bond (-CO-NH-) in their molecules, leading to alteration in the rheological properties of the acid. The impact of hydrolysis at high temperatures on the apparent viscosity of carboxybetaine viscoelastic surfactant-based acids was evaluated in the present study, and the mechanism of viscosity changes was determine by molecular dynamics (MD) simulations.
Our results indicate that, first, significant amount of surfactant has been retained in the carbonate matrix after acidizing treatment and there is a need to use internal breakers when surfactant-based acids are used in dry gas wells or water injectors. Second, hydrolysis at high temperatures has great impact on surfactant-acid rheological properties. Short time viscosity build-up and effective gel break-down can be achieved if surfactant-acid treatments are carefully designed; otherwise, unexpected viscosity reduction and phase separation may occur, which will affect the outcome of acid treatments.
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Printed electronics : Implementation of WORM memory in a RF-antitheft systemHammarling, Krister January 2009 (has links)
Current printable memory technology are not suited for mass produc‐tion. With new inexpensive printed memory, it will be possible to manufacture cheap surveillance tags that are capable to tell the user if something has happened within a timeline. This project is within the ITC FrameProgram 7 founded project PriMeBits. The goal is to imple‐ment a write once read many memory (WORM) onto an RF‐tag together with a sensor that can sense wetness, which can be detected by EAS antitheft systems. Pre researches have been done in the fields printed capacitance, coils and WORMs, all printed with silver ink. Before implementation of a WORM onto a tag simulations and laboratory tests with adjustable resistances were made. Two different circuit models are simulated and tested. When connected to a tag and the WORM is un‐programmed, the EAS system should not trigger an alarm. But if the WORM is programmed by the sensor, the alarm should trigger. Results show that capacitances and WORMs are printable with this technique but coils are not due to high inner resistance. The simulations show that a tag built as an LCCR‐circuit is the best choice. This is also confirmed with tests done with real resistors. With WORMs connected to a tag the results show that approximately 70% of them work as intended, this is because the WORMs as of now are not completely developed. The conclusion of this project is that it is possible to implement a WORM onto a tag with further research, to make an inexpensive surveillance tag. / PriMeBits
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A Proposed Taxonomy of Software Weapons / Ett förslag på taxonomi för programvaruvapenKarresand, Martin January 2002 (has links)
<p>The terms and classification schemes used in the computer security field today are not standardised. Thus the field is hard to take in, there is a risk of misunderstandings, and there is a risk that the scientific work is being hampered. </p><p>Therefore this report presents a proposal for a taxonomy of software based IT weapons. After an account of the theories governing the formation of a taxonomy, and a presentation of the requisites, seven taxonomies from different parts of the computer security field are evaluated. Then the proposed new taxonomy is introduced and the inclusion of each of the 15 categories is motivated and discussed in separate sections. Each section also contains a part briefly outlining the possible countermeasures to be used against weapons with that specific characteristic. </p><p>The final part of the report contains a discussion of the general defences against software weapons, together with a presentation of some open issues regarding the taxonomy. There is also a part discussing possible uses for the taxonomy. Finally the report is summarised.</p>
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龍碧雅寶農 : 綠色農業專家,社區與農民之友 / Lombriabono: helping farmers and communities using green agriculture蘇和, Astorga Solano, Jose B. Unknown Date (has links)
龍碧雅寶農 : 綠色農業專家,社區與農民之友 / Social enterprises are the solution to many of today’s global problems. Although great efforts have been made by nongovernmental organizations and charity, there is still a gap between the world’s most fortunate and less fortunate.
In Nicaragua two of the biggest issues are malnourishment and waste management. Both reinforced by the amount of poverty in the country. LOMBRIABONO looks to bridge the gap in malnourishment while alleviating waste management in the country.
LOMBRIABONO will involve the communities of the state of Carazo in waste management. The people of Carazo will recycle food waste and hand it to one of our partners in the markets. They in turn will receive payment in the form of food for their efforts and their waste. We will then collect the food waste, process it and turn it into vermicomposting, which is an organic fertilizer made with the use of red worms that presents many benefits to the soil, crops and overall health of the population, later selling the vermicomposting, vermicomposting tea and red worms to sustain our business model.
The time is now for our product as people are catching on to the benefits of green agriculture. With the industry being in its embryonic stage, with the proper use of marketing and advertising we will reach thousands of households and bridge that gap caused by poverty all while inspiring other entrepreneurs to start similar ventures.
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Developing security services for network architecturesTham, Kevin Wen Kaye January 2006 (has links)
In the last 15 years, the adoption of enterprise level data networks had increased dramatically. This is mainly due to reasons, such as better use of IT resources, and even better coordination between departments and business units. These great demands have fuelled the push for better and faster connectivity to and from these networks, and even within the networks. We have moved from the slow 10Mbps to 1Gbps connectivity for end-point connections and moved from copper-based ISDN to fibre-linked connections for enterprise connections to the Internet. We now even include wireless network technologies in the mix, because of the greater convenience it offers. Such rapid progress is accompanied by ramifications, especially if not all aspects of networking technologies are improved linearly. Since the 1960s and 1970s, the only form of security had been along the line of authentication and authorisation. This is because of the widely used mainframes in that era. When the Internet and, ultimately, the wide-spread use of the Internet influxed in the 1980s, network security was born, and it was not until the late 1980s that saw the first Internet Worm that caused damage to information and systems on the Internet. Fast forward to today, and we see that although we have come a long way in terms of connectivity (connect to anywhere, and anytime, from anywhere else), the proposed use of network security and network security methods have not improved very much. Microsoft Windows XP recently switched from using their own authentication method, to the use of Kerberos, which was last revised 10 years ago. This thesis describes the many problems we face in the world of network security today, and proposes several new methods for future implementation, and to a certain extend, modification to current standards to encompass future developments. Discussion will include a proposed overview of what a secure network architecture should include, and this will lead into several aspects that can be improved on. All problems identified in this thesis have proposed solutions, except for one. The critical flaw found in the standard IEEE802.11 wireless technology was discovered during the course of this research. This flaw is explained and covered in great detail, and also, an explanation is given as to why this critical flaw is not fixable.
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MÉTODO PARA ENUMERAÇÃO DE OVOS DE HELMINTOS E OOCISTOS DE PROTOZOÁRIOS NA RIZOSFERA DE UMA MACRÓFITA / METHOD FOR HELMINTH EGG AND LISTING PROTOZOAN OOCYSTS IN A MACROPHYTE RHIZOSPHERERodrigues, Daniela Almeida 20 January 2015 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Brazil has a sanitation service with greater deficit coverage, this factor, related to water pollution that receives the discharge of effluents untreated, mainly from domestic sources, as the collection and treatment do not exist or are inadequate. Discharging effluents directly into the ground without proper treatment can lead to contamination of water resources, soil and groundwater, according to local characteristics. Amid this reality, the degradation of natural resources on the campus of UFSM, due to increased academic population, has drawn attention of researchers and managers of the institution. There is a considerable extension of plants as weeds very close to launch domestic Campus of the University, such as Typha domingensis, which are responsible for much of retention of microorganisms in waste water releases and the study location does not exist until the when a microbiological control. This work is justified by the importance of analysis of environmental samples such releases and advocate methodologies for proving the presence of helminth eggs and oocysts of protozoa present in the rhizome of these plants. This factor becomes important by the fact that helminths and protozoa are great cause of gastrointestinal diseases and may, depending on habitat conditions, health and age, cause the individual to death. The study area was next to two buildings in the student's home with release of wastewater. The aim of this study was to develop a methodology to verify the presence of helminth eggs and oocysts of protozoa in the rhizosphere of weeds in natural environment, with release of sewage. The study was conducted in two phases, with the first phase analysis of helminth eggs and oocysts of protozoa present in twelve samples of waste water releases through Bailenger method that occurred during a period of three months, with analysis performed weekly. The second phase was to detect the presence of helminth eggs and oocysts of protozoa with a modified methodology in this paper, called Roberts & Wolff, for analysis of the rhizosphere of the rhizome of macrophyte Typha domingensis in 10 specimens of the plant, also with an approximate time of analysis of three months. The results of the first stage coincide with the data of some studies with wastewater. The results of the second phase even being positive for the presence of helminth eggs and oocysts of protozoa do not make it possible to compare, since there is the analysis results literature helminth eggs and oocysts of protozoa present in the rhizosphere of macrophyte Typha domingensis. As a result of the analysis of the first phase gave an average value of the presence of helminth eggs 112.4 eggs/ L FP35 and 113.5 eggs/ L FP50. Samples of Cryptosporidium sp all samples tested positive for the presence of oocysts and Giardia sp all were negative. In the second phase, we obtained a greater number of eggs found in a sample of one of the analyzed samples and other samples remained very close values of helminth eggs. In Cryptosporidium sp samples only the last three specimens was negative and Giardia sp only a sample of a specimen was positive. / O Brasil possui um serviço de saneamento com maior déficit de cobertura, fator esse, relacionado a poluição das águas que recebe o lançamento de efluentes sem tratamento, principalmente os de origem doméstica, uma vez que a coleta e o tratamento não existe ou é inadequado. O lançamento de efluentes diretamente no solo, sem tratamento adequado pode acarretar a contaminação dos cursos hídricos, do solo e da água subterrânea, de acordo com as características do local. Em meio a essa realidade, a degradação de recursos naturais no Campus da UFSM, devido ao aumento da população acadêmica, tem chamado atenção de pesquisadores e gestores da instituição. Há uma considerável extensão de plantas como macrófitas muito próximas aos lançamentos domésticos no Campus da Universidade, tais como a Typha domingensis, que são responsáveis por uma boa parte de retenção de microrganismos presentes em lançamentos de águas residuais e que no local estudado não existe até o momento um controle microbiológico. O presente trabalho justifica-se pela importância de análises de amostras ambientais desses lançamentos e de preconizar metodologias que possibilitem comprovar a presença de ovos de helmintos e oocistos de protozoários presentes no rizoma dessas plantas. Esse fator torna-se importante pelo fato que helmintos e protozoários são grande causadores de doenças gastrointestinais, podendo, em função das condições de habitat, saúde e idade, levar o indivíduo a morte. A área estudada foi próxima a dois prédios da casa do estudante com lançamento de águas residuais. O objetivo geral desse trabalho foi desenvolver metodologia para verificar a presença de ovos de helmintos e oocistos de protozoários na rizosfera de macrófitas em ambiente natural, com lançamento de efluentes sanitários. O estudo foi desenvolvido em duas fases, tendo como primeira fase a análise de ovos de helmintos e oocistos de protozoários presentes em doze amostras de lançamentos de águas residuais através do método de Bailenger que ocorreu durante um período de três meses, com análise realizadas semanalmente. A segunda fase foi detectar a presença de ovos de helmintos e oocistos de protozoários com uma metodologia modificada neste trabalho, denominada de Rodrigues & Wolff, para análise da rizosfera do rizoma da macrófita Typha domingensis em 10 exemplares da planta, também com um tempo aproximado de análise de três meses. Os resultados da primeira fase coincidem com dados de alguns estudos realizados com águas residuais. Os resultados da segunda fase, mesmo sendo positivos para a presença de ovos de helmintos e oocistos de protozoários não tornam possível a comparação, visto que não existe na literatura resultados de análise de ovos de helmintos e oocistos de protozoários presente na rizosfera da macrófita Typha domingensis. Como resultado das análises da primeira fase obteve-se um valor médio da presença de ovos de helmintos de 112,4 ovos/L na FP35 e 113,5 ovos/L na FP50. Nas amostras de Cryptosporidium sp todas as amostras deram positivas para a presença desse oocisto e Giardia sp todas deram negativas. Na segunda fase, obteve-se um maior número de ovos encontrados em uma das amostras de um dos exemplares analisados e as demais amostras mantiveram valores muito próximos de ovos de helmintos. Nas amostras de Cryptosporidium sp somente as dos últimos três exemplares deu negativo e Giardia sp somente em uma amostra de um exemplar deu positivo.
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Bezpečnostní analýza síťového provozu / Security inspection of network trafficKult, Viktor January 2017 (has links)
Thesis topic concerns the issue of information security in corporate environments. Literature search includes information obtained by studying articles and literature in the field of information security. Resources were selected with a focus on the security risks, security technologies and legislative regulation. Attention is focused on technology that supports monitoring of communication flows in the data network. Overview of traffic operating a data network provides important information for the prevention or investigation of security incidents. Monitoring also serves as a source of information for the planning of the network infrastructure. It can detect faults or insufficient transmission capacity. The practical part is dedicated to implementation of the monitoring system in the real corporate networks. Part of the experience is the analysis of the network structure and choice of appropriate tools for actual implementation. When selecting tools, you can use the scoring method of multicriterial analysis options. The integration of the monitoring system is also the configuration of active network elements. Subsequent analysis of network traffic provides information about the most active users, most used applications or on the sources and targets of data transmitted. It provides a source of valuable information that can be used in case of failure on the network or security incident. The conclusion is a summary of the results and workflow.
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Resistência de germoplasma silvestre de amendoim (arachis spp.) a Enneothrips flavens Moulton, 1941 (Thysanoptera: Thripidae) e Stegasta bosquella (Chambers, 1875) (Lepidoptera: Gelechiidae)Janini, Júlio César [UNESP] 21 December 2011 (has links) (PDF)
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janini_jc_dr_jabo.pdf: 736828 bytes, checksum: dedc921637a05675cb39383183591b7a (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / As pragas e doenças estão entre as principais limitações para a cultura do amendoim e a resistência a esses agentes constitui importante objetivo para o melhoramento genético. Entre as pragas, as que mais limitam a produtividade, principalmente no estado de São Paulo, estão o tripes-do-prateamento, Enneothrips flavens Moulton, 1941 (Thysanoptera: Thripidae) e a lagarta-do-pescoço-vermelho, Stegasta bosquella (Chambers, 1875) (Lepidoptera: Gelechiidae). Moderada variabilidade para resistência tem sido observada no amendoim cultivado, Arachis hypogaea, mas, no germoplasma silvestre de Arachis, trabalhos recentes têm mostrado significativas diferenças entre espécies quanto às infestações e danos causados por ambas as pragas. Este trabalho teve como objetivos avaliar e identificar acessos de germoplasma de Arachis potencialmente resistentes ao tripes e lagarta-do-pescoço-vermelho e estudar os possíveis mecanismos envolvidos nesta resistência. Incluem-se entre esses acessos alguns anfidiplóides, híbridos obtidos de cruzamentos entre espécies. Os experimentos foram conduzidos em campo e em laboratório, na Faculdade de Ciências Agrárias e Veterinárias/UNESP - Campus de Jaboticabal, SP, nos anos agrícolas de 2009/2010 e 2010/2011. Na etapa de campo, no primeiro ano, dezoito acessos de espécies silvestres, um anfidiploide e dois cultivares de A. hypogaea e, no segundo, oito espécies, cinco anfidiplóides e um cultivar foram avaliados quanto à infestação e sintomas de danos causados pelos dois insetos, e quanto à porcentagem de redução de crescimento vegetativo e produção de sementes em tratamentos com e sem aplicação de inseticidas. Na etapa de laboratório, estudaram-se os acessos e anfidiploide que se destacaram na etapa de campo. No primeiro ano... / Insect pests and diseases are major limitations to the peanut crop, and resistance to these agents is an important breeding objective. Among the insects, thrips Enneothrips flavens, Moulton, 1941 (Thysanoptera: Thripidae) and rednecked worm, Stegasta bosquella, (Chambers, 1875) (Lepidoptera: Gelechiidae) are the major key-pests especially in the state of São Paulo. Moderate variability for resistance has been observed in A. hypogaea cultivars, but, within the germplasm pool of Arachis, recent works have shown significant differences between species as to infestations and damages from both insects. This research was done with the objectives of evaluating and identifying Arachis germplasm accessions potentially resistant to E. flavens and S. bosquella, and study possible mechanisms involved with this resistance. Some amphidiploids, hybrids between wild species, were also included. The experiments were carried out in field and laboratory stages at the Faculdade de Ciências Agrárias e Veterinárias/UNESP - Campus de Jaboticabal, SP, during the growing seasons of 2009/2010 and 2010/2011. In the field stage, in the first year, eighteen Arachis accessions, one amphidiploid and two A. hypogaea cultivars were evaluated and, in the second year eight accessions, five amphidiploids and a cultivar were assessed for infestation and damage ratings caused by both insects, as well as for percentage of reduction in vegetative growth and seed yield with and without insecticide application for insect cultivars. In the lab stage, accessions and amphidiploids that had the best behavior in the field were studied. In the first year, eight accessions and a A. hypogaea, and in the second, five accessions, an amphidiploids and a cultivar were evaluated for non preference of feeding and insect biology. In field conditions, the large majority of the wild... (Complete abstract click electronic access below)
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Resistência de germoplasma silvestre de amendoim (arachis spp.) a Enneothrips flavens Moulton, 1941 (Thysanoptera: Thripidae) e Stegasta bosquella (Chambers, 1875) (Lepidoptera: Gelechiidae) /Janini, Júlio César. January 2011 (has links)
Orientador: Arlindo Leal Boiça Júnior / Coorientador: Ignácio José de Godoy / Coorientador: Marcos Doniseti Michelotto / Banca: André Luiz Lourenção / Banca: Valter Arthur / Banca: Júlio César Galli / Banca: Ricardo Antonio Polanczyk / Resumo: As pragas e doenças estão entre as principais limitações para a cultura do amendoim e a resistência a esses agentes constitui importante objetivo para o melhoramento genético. Entre as pragas, as que mais limitam a produtividade, principalmente no estado de São Paulo, estão o tripes-do-prateamento, Enneothrips flavens Moulton, 1941 (Thysanoptera: Thripidae) e a lagarta-do-pescoço-vermelho, Stegasta bosquella (Chambers, 1875) (Lepidoptera: Gelechiidae). Moderada variabilidade para resistência tem sido observada no amendoim cultivado, Arachis hypogaea, mas, no germoplasma silvestre de Arachis, trabalhos recentes têm mostrado significativas diferenças entre espécies quanto às infestações e danos causados por ambas as pragas. Este trabalho teve como objetivos avaliar e identificar acessos de germoplasma de Arachis potencialmente resistentes ao tripes e lagarta-do-pescoço-vermelho e estudar os possíveis mecanismos envolvidos nesta resistência. Incluem-se entre esses acessos alguns anfidiplóides, híbridos obtidos de cruzamentos entre espécies. Os experimentos foram conduzidos em campo e em laboratório, na Faculdade de Ciências Agrárias e Veterinárias/UNESP - Campus de Jaboticabal, SP, nos anos agrícolas de 2009/2010 e 2010/2011. Na etapa de campo, no primeiro ano, dezoito acessos de espécies silvestres, um anfidiploide e dois cultivares de A. hypogaea e, no segundo, oito espécies, cinco anfidiplóides e um cultivar foram avaliados quanto à infestação e sintomas de danos causados pelos dois insetos, e quanto à porcentagem de redução de crescimento vegetativo e produção de sementes em tratamentos com e sem aplicação de inseticidas. Na etapa de laboratório, estudaram-se os acessos e anfidiploide que se destacaram na etapa de campo. No primeiro ano... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Insect pests and diseases are major limitations to the peanut crop, and resistance to these agents is an important breeding objective. Among the insects, thrips Enneothrips flavens, Moulton, 1941 (Thysanoptera: Thripidae) and rednecked worm, Stegasta bosquella, (Chambers, 1875) (Lepidoptera: Gelechiidae) are the major key-pests especially in the state of São Paulo. Moderate variability for resistance has been observed in A. hypogaea cultivars, but, within the germplasm pool of Arachis, recent works have shown significant differences between species as to infestations and damages from both insects. This research was done with the objectives of evaluating and identifying Arachis germplasm accessions potentially resistant to E. flavens and S. bosquella, and study possible mechanisms involved with this resistance. Some amphidiploids, hybrids between wild species, were also included. The experiments were carried out in field and laboratory stages at the Faculdade de Ciências Agrárias e Veterinárias/UNESP - Campus de Jaboticabal, SP, during the growing seasons of 2009/2010 and 2010/2011. In the field stage, in the first year, eighteen Arachis accessions, one amphidiploid and two A. hypogaea cultivars were evaluated and, in the second year eight accessions, five amphidiploids and a cultivar were assessed for infestation and damage ratings caused by both insects, as well as for percentage of reduction in vegetative growth and seed yield with and without insecticide application for insect cultivars. In the lab stage, accessions and amphidiploids that had the best behavior in the field were studied. In the first year, eight accessions and a A. hypogaea, and in the second, five accessions, an amphidiploids and a cultivar were evaluated for non preference of feeding and insect biology. In field conditions, the large majority of the wild... (Complete abstract click electronic access below) / Doutor
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CaracterizaÃÃo fenotÃpica e resposta imune de caprinos naturalmente infectados por nematoides gastrintestinais / Phenotypic characterization and immune response of goat crossbreds naturally infected by gastrointestinal nematodeMaria Rosalba Moreira das Neves 31 October 2014 (has links)
CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior / O objetivo deste estudo foi avaliar ferramentas fenotÃpicas, histolÃgicas, imunolÃgicas e moleculares para caracterizar caprinos mestiÃos quanto à resistÃncia e susceptibilidade aos nematoides gastrintestinais. Para isso, foram utilizados 231 animais F2, de ambos os sexos, com idade variando de cinco a dez meses, provenientes de quatro lotes experimentais. Semanalmente, foram coletadas amostras de fezes e sangue para realizaÃÃo dos exames: contagem de ovos por grama de fezes (OPG), coprocultura, volume globular (VG), proteÃna plasmÃtica total (PPT), eosinÃfilos sanguÃneos (EOS) e determinaÃÃo dos nÃveis de imunoglobulinas. Nos mesmos dias das coletas, tambÃm foi realizado o mÃtodo Famacha. Os animais foram ordenados de acordo com os valores de OPG, os 12 animais que apresentaram as menores mÃdias foram caracterizados como resistentes e os 12 animais que apresentaram as maiores mÃdias foram caracterizados como susceptÃveis. Os animais do lote experimental 4, como apresentaram a melhor caracterizaÃÃo fenotÃpica, foram necropsiados para a recuperaÃÃo dos nematoides gastrintestinais e amostras de tecidos para anÃlises histolÃgicas e de expressÃo gÃnica. O OPG foi eficaz, nos quatro lotes, para a caracterizaÃÃo de caprinos resistentes e susceptÃveis as parasitoses gastrintestinais nos dois desafios de infecÃÃo (P<0,05). No quarto lote, as variÃveis: OPG, VG e PPT foram eficazes na identificaÃÃo dos animais quanto a diferentes nÃveis de resistÃncia. Nos demais lotes, o VG, a PPT, a contagem de eosinÃfilos e o Famacha nÃo foram tÃo eficazes como o OPG, para diferenciar caprinos resistentes e susceptÃveis Ãs parasitoses gastrintestinais. Os nÃveis de IgA e IgG, em especial para Haemonchus contortus, nos dois desafios de infecÃÃo, e a contagem de eosinÃfilos no abomaso foram parÃmetros eficazes na resposta imune, indicando que essas cÃlulas de defesa apresentam um papel efetor no controle das infecÃÃes gastrintestinais. Na expressÃo gÃnica, a IL-5 e IL-10 apresentaram nÃveis superiores significativos no grupo susceptÃvel, mostrando que a expressÃo destas citocinas na quinta semana de infecÃÃo pode ter papel em mecanismos de susceptibilidade a nematoides gastrintestinais. / The aim of this study was to evaluate phenotypic, histologic, immunologic and molecular tools to characterize goat crossbred in resistant and susceptibily to gastrointestinal nematodes. For this purpose, we used 231 F2 animals of both genders, of ages between five and ten months, from four different kidding seasons. Stool and blood samples were collected weekly for eggs per gram of feces (EPG) determinations, fecal culture, packed cell volume (PCV), total plasma protein (TPP), blood eosinophils (EOS) and immunological tests. Famacha scores were obtained on the same sample collection days. The animals were ranked according to EPG values and the 12 animals with lowest means were considered resistant while the 12 animals with the highest means were considered susceptible. The animals in the experimental lot 4, presented the best phenotypic characterization and were chosen for, recovery of gastrointestinal nematodes and tissue samples for histological and gene expression determinations. EPG, PCV and TPP were effective in the identification of resistant and susceptible. In the other lots, the PCV, TPP, eosinophil count and Famacha were not as effective as EPG. IgG and IgA levels, particularly for Haemonchus contortus infection in both challenges, showed significant differences in some of the studied timepoints. Resistant animals presented higher eosinophil counts in the abomasum, indicating that these cells participate in the control of gastrointestinal infections. IL-5 and IL-10 gene expression levels were significantly higher in the susceptible group, showing that the expression of these cytokines in the fifth week of infection may have a role in mechanisms of susceptibility to gastrointestinal nematodes.
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