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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.
1

Determinação da concentração de nitrogênio uréico no plasma como ferramenta auxiliar no manejo sustentável em rebanhos leiteiros sergipanos / Determination of the concentration of plasma urea nitrogen as an auxiliary tool in the sustainable management of dairy herds in Sergipe

Lira, Flávia Rejane de Andrade 29 April 2011 (has links)
The dairy cattle is a source of income for thousands of producers in Brazil, with growing production data, especially in the Northeast, making it essential that they be encouraged to create sustainable processes, causing producers to be competitive, earning profits and quality of life in a responsible manner. In this sense, monitoring the remnants of the protein intake in the diet of lactating cows, allows a rational use of concentrate supplementation, promoting a reduction in production costs, and prevent loss of nitrogen to the environment. The concentration of plasma urea nitrogen (PUN) can be an important auxiliary tool in the implementation and adjustment of feeding strategies, because it reflects the nutritional protein, the efficiency of nitrogen utilization by the animal and the ruminal balance between nitrogen (N) and energy. Its use as a routine, can help professionals in rural technical assistance, the ease of performing the examination in any laboratory animal or human clinical analysis, and can be used in non-lactating animals and other animal categories. The aim of this study was to evaluate the concentration of plasma urea nitrogen (PUN) in different dairy herds in order to obtain a diagnosis of levels of dietary protein utilization of lactating cows and to relate these levels with economic and productive aspects. The experiment was conducted in 25 farms with the exploitation of dairy cattle in the town of Nossa Senhora da Glória (SE), where blood samples were collected in five cows per farm, every 30 days over a period of three consecutive months, to determination of the PUN. Then, we selected 10 properties, valued between 25 and showing greater zootechnic control, to analyze possible PUN associations with nutritional parameters, productive and reproductive, as well as assess the commitment of the income of milk with concentrate supplementation. The experimental design was completely randomized split plot in time, obtaining variations of PUN between 6.97 and 29.2 mg / dL (P <0.05) and overall average of 15.46 mg / dL between the properties, where only 37.33% of them presented PUN within the patterns, and found that increasing levels of crude protein (CP) in the diet resulted in elevated values of PUN and reduced reproductive efficiency. It was also observed, that the mean of a 38.17% of income from milk, with the use of concentration between the properties. Under the conditions of this diagnosis, it appears that the present levels of PUN is not standard in most properties, possibly influenced by crude protein (CP) in the diet, resulting in higher production costs of dairy. / A bovinocultura leiteira representa uma fonte de renda para milhares de produtores no Brasil, apresentando dados produtivos crescentes, principalmente no Nordeste, tornando-se fundamental que sejam estimulados processos de criação sustentáveis, fazendo com que os produtores sejam competitivos, auferindo lucros e qualidade de vida, de forma responsável. Neste sentido, o monitoramento das sobras da proteína ingerida na dieta das vacas em lactação, permite uma utilização racional da suplementação concentrada, promovendo uma redução nos custos de produção, além de evitar perdas de nitrogênio para o meio ambiente. A concentração do nitrogênio ureico no plasma (NUP) pode ser uma ferramenta auxiliar importante, na implantação e ajustes de estratégias de alimentação, pois reflete o estado nutricional protéico, a eficiência da utilização do nitrogênio pelo animal e o equilíbrio ruminal entre nitrogênio (N) e energia. Seu uso como rotina, pode auxiliar profissionais da assistência técnica rural, pela facilidade da realização do exame em qualquer laboratório de análise clínica humana ou animal, além de poder ser utilizado em animais não lactantes e em outras categorias animais. O objetivo dessa pesquisa foi avaliar a concentração de nitrogênio uréico no plasma (NUP) em diferentes rebanhos leiteiros, de modo a obter um diagnóstico dos níveis de aproveitamento protéico dietético de vacas em lactação e relacionar esses níveis, com aspectos produtivos e econômicos. O experimento foi conduzido em 25 propriedades rurais com exploração de bovinocultura leiteira, no município de Nossa Senhora da Glória (SE), onde foram realizadas coletas de sangue em cinco vacas por propriedade, a cada 30 dias, num período de três meses seguidos, para determinação do NUP. Em seguida, foram selecionadas 10 propriedades, entre as 25 avaliadas, que apresentavam maior controle zootécnico, para analisar possíveis associações do NUP com parâmetros nutricionais, produtivos e reprodutivos, além da avaliar o comprometimento da renda do leite (CRL) com a suplementação concentrada. O delineamento experimental foi inteiramente casualizado, em parcelas subdivididas no tempo, obtendo variações de NUP entre 6,97 e 29,2 mg/dL (P<0,05) e média geral de 15,46mg/dL entre as propriedades, onde apenas 37,33% delas apresentou NUP dentro dos padrões, sendo verificado que níveis crescentes de proteína bruta (PB) na dieta resultaram na elevação dos valores de NUP e redução da eficiência reprodutiva. Foi observado também, um comprometimento médio de 38,17% da renda do leite (CRL), com a utilização de concentrado, entre as propriedades. Nas condições desse diagnóstico, verifica-se que os níveis de NUP apresentam-se fora dos padrões na maioria das propriedades, possivelmente influenciados pela proteína bruta (PB) na dieta, repercutindo num maior custo de produção da atividade leiteira.
2

Understanding the Resilience of Educational Disparities for Migrant Children in Urban China, in the Context of Hukou Reform

Bourgeois-Fortin, Camille 17 January 2023 (has links)
Educational disparities in China are rooted in the country’s longstanding rural-urban divide, which the hukou system has institutionalized. However, following a comprehensive reform of the hukou system (2014-2020) disparities in access to education remain ubiquitous. This raises questions regarding the reform itself, in terms of its agenda and effectiveness, as well as regarding the real driving factors of educational disparities in urban China. It is a complex issue that requires a multidimensional analysis, which shall consider both the hukou and other exclusionary factors as potential causes. These include mechanisms inherent to China’s education system, culture, and historical dynamics of social stratification. Making an in-depth review of the literature through institutionalism lenses, this research takes shape in the theoretical and conceptual frameworks of equality of opportunity and social mobility. Supported by empirical indicators and qualitative data, it provides an in-depth and timely understanding of the hukou and underlying factors of educational exclusion that undermine equality of opportunity and hinder upward social mobility among migrant children. This research finds that hukou status is still the biggest determinant of people’s equality of opportunities and social mobility in China and argues that the reform had the potential to make a positive difference. Thereby, this research's main explanation for the resilience of educational disparities in this context is that the 2014 hukou reform’s core intent was to modify migrant spatial distribution in favour of small and midsize cities, as opposed to their current concentration in megacities, and, in doing so, policymakers overlooked many challenges and barriers associated to migrating to lower tier cities and undervalued the importance of education for migrants. This research thus concludes that, rather than a definite lack of political will for solving educational disparities, the reform fell short on schooling issues because economic ambitions have taken precedence over social development and equal access to welfare, including education, among all Chinese citizens.
3

Analyses of mitotic nuclear pore complex dynamics in <i>Aspergillus nidulans</i>

Liu, Hui-Lin 03 September 2009 (has links)
No description available.
4

Technical Verification and Validation of ADS-B/VDL Mode 4 for A-SMGCS / Teknisk verifiering och validering av ADS-B/VDL Mode 4 för A-SMGCS

Eriksson, Matts, Lundmark, Jonas January 2002 (has links)
This report is a technical verification and validation of ADS-B (Automatic Dependent Surveillance – Broadcast) over VDL Mode 4 (Very High Frequency Data Link Mode 4) for the use in the surveillance element of an A-SMGCS (Advanced Surface Movement Guidance and Control System). The main objective of this report is to examine if ADS-B/VDL Mode 4 fulfils the technical requirements for an implementation at Arlanda airport, Stockholm Sweden. The report also includes a FMECA (Failure Mode, Effects and Criticality Analysis), a theoretical background and methods for monitoring. The process of making this report can be divided into three phases: 1. Preliminary Study. In this phase the requirements were examined and structured. 2. Verification. In this phase the system performance has been verified both theoretically and by several tests at Arlanda Airport. Simulation results have also been used. 3. Validation and documentation. The tests and verifications that were performed in phase 2 were validated in the third phase of the project. The final project document was also written in this phase. The main conclusion from this analysis is that ADS-B/VDL Mode 4 is well suited for surveillance. ADS-B/VDL Mode 4 has the possibility to fulfil all considered requirements, apart from detecting all obstacles. But if all the requirements are going to be fulfilled depends both on the implementation and the operational environment. The results from this verification and validation should be used as the technical subset in a future safety case, both in Sweden and internationally.
5

Technical Verification and Validation of ADS-B/VDL Mode 4 for A-SMGCS / Teknisk verifiering och validering av ADS-B/VDL Mode 4 för A-SMGCS

Eriksson, Matts, Lundmark, Jonas January 2002 (has links)
<p>This report is a technical verification and validation of ADS-B (Automatic Dependent Surveillance – Broadcast) over VDL Mode 4 (Very High Frequency Data Link Mode 4) for the use in the surveillance element of an A-SMGCS (Advanced Surface Movement Guidance and Control System). </p><p>The main objective of this report is to examine if ADS-B/VDL Mode 4 fulfils the technical requirements for an implementation at Arlanda airport, Stockholm Sweden. The report also includes a FMECA (Failure Mode, Effects and Criticality Analysis), a theoretical background and methods for monitoring. </p><p>The process of making this report can be divided into three phases: </p><p>1. Preliminary Study. In this phase the requirements were examined and structured. </p><p>2. Verification. In this phase the system performance has been verified both theoretically and by several tests at Arlanda Airport. Simulation results have also been used. </p><p>3. Validation and documentation. The tests and verifications that were performed in phase 2 were validated in the third phase of the project. The final project document was also written in this phase. </p><p>The main conclusion from this analysis is that ADS-B/VDL Mode 4 is well suited for surveillance. ADS-B/VDL Mode 4 has the possibility to fulfil all considered requirements, apart from detecting all obstacles. But if all the requirements are going to be fulfilled depends both on the implementation and the operational environment. </p><p>The results from this verification and validation should be used as the technical subset in a future safety case, both in Sweden and internationally.</p>
6

Efeitos do fornecimento de dietas contendo nitrogênio não-protéico(NNP) sem prévia adaptação, durante curto espaço de tempo e em diferentes fases do ciclo estral na produção, qualidade e grau de desenvolvimento de embriões de fêmeas bovinas superovuladas / Effect of short term non-protein nitrogen (NPN) feeding to superovulated beef cows without previous adaptation, at different periods of the oestrus cycle on yield, quality and development degree of recovered embryos

Alves, Flavio Rocha 13 December 2007 (has links)
Níveis elevados de proteína bruta (PB) na dieta de ruminantes têm sido associado com comprometimento na fertilidade devido, principalmente, a elevação da concentração do nitrogênio uréico plasmático (NUP). Objetivou-se no presente estudo avaliar o efeito do fornecimento de dietas contendo nitrogênio não-protéico (NNP) sem prévia adaptação, durante curto espaço de tempo e em diferentes fases do ciclo estral, a fêmeas bovinas superovuladas quanto à produção, qualidade e ao grau de desenvolvimento de embriões recuperados. Sessenta e oito vacas da raça Nelore com escore corporal de 7,56 e peso médio de 557,6 kg foram distribuídas em três tratamentos: controle (C), uréia antes do dia 0 (UA; fornecimento de dieta com uréia do dia -5 ao dia 0) e uréia depois do dia 0 (UD; fornecimento de dieta com uréia do dia 0 ao dia 5). As vacas foram mantidas em piquetes com pastagem de Brachiaria brizantha cv. Marandu e receberam diariamente, 3,0 kg/animal de concentrado durante 16 dias. Foram formulados dois concentrados, sendo que as dietas totais (concentrado + consumo estimado de pastagem) continham 12,0% (dieta controle) e 14,6% de PB (dieta com NNP). A diferença na PB entre as dietas foi o acréscimo de 100g/vaca/dia de uréia. Os animais foram sincronizados, superovulados e inseminados. Sete dias (dia 7) após a inseminação (dia 0), realizou-se a colheita e análise dos embriões quanto à qualidade a ao grau de desenvolvimento. Amostras de sangue foram coletadas nos dias -5, 0 e 5 para mensurações das concentrações de NUP, glicose, insulina e progesterona. Houve efeito significativo dos tratamentos sobre a concentração médias de NUP no dia -5 (C = 16,18ab, UA = 17,72a e UD = 14,47b mg/dL; P = 0,0007), no dia 0 (C = 18,95b, UA = 22,71a e UD = 21,15 ab mg/dL; P = 0,0010) e no dia 5 (C = 20,93a, UA = 19,08b e UD = 21,51a mg/dL; P = 0,0022). Quanto às concentrações de glicose, insulina e progesterona não houve efeito dos tratamentos. Não houve efeito significativo nem da inclusão da uréia e nem do momento da inclusão da uréia sobre o total de estruturas recuperadas, total de estruturas fecundadas e de embriões viáveis. Porém, houve efeito do momento de inclusão da uréia sobre a porcentagem de estruturas fecundadas em relação ao total de estruturas recuperadas (UA = 75,3 vs. UD = 50,7%) e sobre a porcentagem de embriões viáveis em relação ao total de estruturas recuperadas (UA = 73,2 vs. UD = 39,4%). O tratamento UD acarretou em menor capacidade de fecundação do oócito em relação ao tratamento UA, havendo redução de aproximadamente 32,7% na proporção de oócitos fecundados sobre o total de estruturas recuperadas deste tratamento. / High levels of crude protein (CP) in ruminant diets were associated with detrimental effect on fertility, mainly, due to the rise of plasmatic urea nitrogen (PUN) concentration. The aim of this study was to verify the effects of short term non-protein nitrogen feeding at different periods of the oestrus cycle in superovulated cows without previous adaptation on yield, quality and development degree of recovered embryos. Sixty eight Nelore cows with body condition score of 7.56 and body weight of 557.6 kg were divided in three different groups: control (C), urea before day 0 (UB; urea supply from day -5 to day 0) and urea after day 0 (UA; urea supply from day 0 to day 5). Animals were grazing in Brachiaria brizantha cv. Marandu pasture and received 3.0 kg/animal/day of concentrate during 16 days. Two concentrates were formulated and the total diets (concentrate + estimate forage intake) had 12.0% (control diet) and 14.6% of CP (NPN diet). The difference in CP between diets was the addition of 100g/cow/day of urea. Animals were synchronized, superovulated and inseminated. The embryos were collected seven days (day 7) after insemination (day 0) and quality and development degree were also evaluated. Blood samples were collected on day -5, 0 and 5 for measurement of PUN, glucose, insulin and progesterone. There was significant effect of treatments on average PUN concentration at day -5 (C = 16.18ab, UB = 17.72a and UA = 14.47b mg/dL; P = 0.0007), at day 0 (C = 18.95b, UB = 22.71a and UA = 21.15ab mg/dL; P = 0.0010) and at day 5 (C = 20.93a, UB = 19.08b and UA = 21.51a mg/dL; P = 0.0022). For glucose, insulin and progesterone there was no effect of treatments. It was observed neither effect of urea inclusion nor the moment of urea inclusion in diet on the total number of recovered structures, total number of fertilized structures and total number of viable embryos. However, it was observed effect of the moment of urea inclusion on the rate of fertilized structures in relation to the total number of recovered structures (UB = 75.3 vs. UA = 50.7%) and on the rate of viable embryos in relation to the total number of recovered structures (UB = 73.2 vs. UA = 39.4%). The UA treatment lead to lowest fertilizing oocyte capacity in relation to UB treatment with an approximate reduction of 32.7% on oocytes fertilized proportion over the total recovered structures in this treatment.
7

Efeitos do fornecimento de dietas contendo nitrogênio não-protéico(NNP) sem prévia adaptação, durante curto espaço de tempo e em diferentes fases do ciclo estral na produção, qualidade e grau de desenvolvimento de embriões de fêmeas bovinas superovuladas / Effect of short term non-protein nitrogen (NPN) feeding to superovulated beef cows without previous adaptation, at different periods of the oestrus cycle on yield, quality and development degree of recovered embryos

Flavio Rocha Alves 13 December 2007 (has links)
Níveis elevados de proteína bruta (PB) na dieta de ruminantes têm sido associado com comprometimento na fertilidade devido, principalmente, a elevação da concentração do nitrogênio uréico plasmático (NUP). Objetivou-se no presente estudo avaliar o efeito do fornecimento de dietas contendo nitrogênio não-protéico (NNP) sem prévia adaptação, durante curto espaço de tempo e em diferentes fases do ciclo estral, a fêmeas bovinas superovuladas quanto à produção, qualidade e ao grau de desenvolvimento de embriões recuperados. Sessenta e oito vacas da raça Nelore com escore corporal de 7,56 e peso médio de 557,6 kg foram distribuídas em três tratamentos: controle (C), uréia antes do dia 0 (UA; fornecimento de dieta com uréia do dia -5 ao dia 0) e uréia depois do dia 0 (UD; fornecimento de dieta com uréia do dia 0 ao dia 5). As vacas foram mantidas em piquetes com pastagem de Brachiaria brizantha cv. Marandu e receberam diariamente, 3,0 kg/animal de concentrado durante 16 dias. Foram formulados dois concentrados, sendo que as dietas totais (concentrado + consumo estimado de pastagem) continham 12,0% (dieta controle) e 14,6% de PB (dieta com NNP). A diferença na PB entre as dietas foi o acréscimo de 100g/vaca/dia de uréia. Os animais foram sincronizados, superovulados e inseminados. Sete dias (dia 7) após a inseminação (dia 0), realizou-se a colheita e análise dos embriões quanto à qualidade a ao grau de desenvolvimento. Amostras de sangue foram coletadas nos dias -5, 0 e 5 para mensurações das concentrações de NUP, glicose, insulina e progesterona. Houve efeito significativo dos tratamentos sobre a concentração médias de NUP no dia -5 (C = 16,18ab, UA = 17,72a e UD = 14,47b mg/dL; P = 0,0007), no dia 0 (C = 18,95b, UA = 22,71a e UD = 21,15 ab mg/dL; P = 0,0010) e no dia 5 (C = 20,93a, UA = 19,08b e UD = 21,51a mg/dL; P = 0,0022). Quanto às concentrações de glicose, insulina e progesterona não houve efeito dos tratamentos. Não houve efeito significativo nem da inclusão da uréia e nem do momento da inclusão da uréia sobre o total de estruturas recuperadas, total de estruturas fecundadas e de embriões viáveis. Porém, houve efeito do momento de inclusão da uréia sobre a porcentagem de estruturas fecundadas em relação ao total de estruturas recuperadas (UA = 75,3 vs. UD = 50,7%) e sobre a porcentagem de embriões viáveis em relação ao total de estruturas recuperadas (UA = 73,2 vs. UD = 39,4%). O tratamento UD acarretou em menor capacidade de fecundação do oócito em relação ao tratamento UA, havendo redução de aproximadamente 32,7% na proporção de oócitos fecundados sobre o total de estruturas recuperadas deste tratamento. / High levels of crude protein (CP) in ruminant diets were associated with detrimental effect on fertility, mainly, due to the rise of plasmatic urea nitrogen (PUN) concentration. The aim of this study was to verify the effects of short term non-protein nitrogen feeding at different periods of the oestrus cycle in superovulated cows without previous adaptation on yield, quality and development degree of recovered embryos. Sixty eight Nelore cows with body condition score of 7.56 and body weight of 557.6 kg were divided in three different groups: control (C), urea before day 0 (UB; urea supply from day -5 to day 0) and urea after day 0 (UA; urea supply from day 0 to day 5). Animals were grazing in Brachiaria brizantha cv. Marandu pasture and received 3.0 kg/animal/day of concentrate during 16 days. Two concentrates were formulated and the total diets (concentrate + estimate forage intake) had 12.0% (control diet) and 14.6% of CP (NPN diet). The difference in CP between diets was the addition of 100g/cow/day of urea. Animals were synchronized, superovulated and inseminated. The embryos were collected seven days (day 7) after insemination (day 0) and quality and development degree were also evaluated. Blood samples were collected on day -5, 0 and 5 for measurement of PUN, glucose, insulin and progesterone. There was significant effect of treatments on average PUN concentration at day -5 (C = 16.18ab, UB = 17.72a and UA = 14.47b mg/dL; P = 0.0007), at day 0 (C = 18.95b, UB = 22.71a and UA = 21.15ab mg/dL; P = 0.0010) and at day 5 (C = 20.93a, UB = 19.08b and UA = 21.51a mg/dL; P = 0.0022). For glucose, insulin and progesterone there was no effect of treatments. It was observed neither effect of urea inclusion nor the moment of urea inclusion in diet on the total number of recovered structures, total number of fertilized structures and total number of viable embryos. However, it was observed effect of the moment of urea inclusion on the rate of fertilized structures in relation to the total number of recovered structures (UB = 75.3 vs. UA = 50.7%) and on the rate of viable embryos in relation to the total number of recovered structures (UB = 73.2 vs. UA = 39.4%). The UA treatment lead to lowest fertilizing oocyte capacity in relation to UB treatment with an approximate reduction of 32.7% on oocytes fertilized proportion over the total recovered structures in this treatment.
8

Technical Verification and Validation of TIS-B using VDL Mode 4

Fredriksson, Daniel, Schweitz, Anders January 2004 (has links)
<p>This report is a technical verification and validation of Traffic Information Service Broadcast (TIS-B) using the data link VDL Mode 4. </p><p>The main objective of the report is to examine the usefulness of TIS-B considering the results from tests performed in the Stockholm Terminal Area and for the Advanced Surface Movement Guidance and Control System (A-SMGCS) at Arlanda airport. The results are compared with the requirements that have been set by the standardisation organisations ICAO, RTCA, Eurocontrol and Eurocae. TIS-B is however such a new concept, so most of the operational requirements have not yet been defined.</p><p>The process for performing the evaluation of TIS-B involves three stages: </p><p>· Study the requirements on TIS-B, ADS-B, radar and A-SMGCS. </p><p>· Verify TIS-B by performing tests at Arlanda airport. </p><p>· Validate the test results through analysis. </p><p>A theoretical study of slot allocation optimisation is performed to decide how the slot allocation is to be implemented. </p><p>The report includes a Functional Hazard Analysis (FHA). The FHA is done to see if the applications for TIS-B are ready for implementation or if more hazard preventing actions has to be taken, before any operational actions can be performed. </p><p>The report also involves a theoretical introduction to Air Traffic Management (ATM), Surveillance techniques and TIS-B. </p><p>All parts included in the report results in conclusions and recommendations regarding the TIS-B service.</p>
9

Technical Verification and Validation of TIS-B using VDL Mode 4

Fredriksson, Daniel, Schweitz, Anders January 2004 (has links)
This report is a technical verification and validation of Traffic Information Service Broadcast (TIS-B) using the data link VDL Mode 4. The main objective of the report is to examine the usefulness of TIS-B considering the results from tests performed in the Stockholm Terminal Area and for the Advanced Surface Movement Guidance and Control System (A-SMGCS) at Arlanda airport. The results are compared with the requirements that have been set by the standardisation organisations ICAO, RTCA, Eurocontrol and Eurocae. TIS-B is however such a new concept, so most of the operational requirements have not yet been defined. The process for performing the evaluation of TIS-B involves three stages: · Study the requirements on TIS-B, ADS-B, radar and A-SMGCS. · Verify TIS-B by performing tests at Arlanda airport. · Validate the test results through analysis. A theoretical study of slot allocation optimisation is performed to decide how the slot allocation is to be implemented. The report includes a Functional Hazard Analysis (FHA). The FHA is done to see if the applications for TIS-B are ready for implementation or if more hazard preventing actions has to be taken, before any operational actions can be performed. The report also involves a theoretical introduction to Air Traffic Management (ATM), Surveillance techniques and TIS-B. All parts included in the report results in conclusions and recommendations regarding the TIS-B service.

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