Newcastle disease (ND), caused by Newcastle disease virus, is an acute, contagious and pathogenic infection of pet, free living and domestic birds. ND is an epidemic disease and it is responsible for high economic losses due to up to 100 % mortality. The control of ND in the intensive commercial poultry farms is largely dependent on prophylactic immunisation using conventional vaccines. The ND V4 vaccine and its derivative ND V4-HR vaccine were selected originally for use in village chickens, due to their immunogenicity, thermostability, transmissibility and ease of administration. The efficacy of V4 and V4HR vaccines have been established in many Asian and African countries in their ability to challenge a wide range of recognised and local velogenic NDV. Therefore, ND V4 was tested for efficacy against B1172 challenge NDV isolated in south Africa in 1993. Twenty-eight one day-old replacement pullets were vaccinated by eye-drop route at 21 and 49 days old. Chickens vaccinated by eye-drop route were left to mingle with the unvaccinated in-contact chickens. At 63 days all chickens including the unvaccinated control group were individually challenged with B1172 NDV. Serological monitoring of NDV antibody response was done using HI and ELISA tests. The ND V4 vaccine induced full protection against B1172 NDV in chickens vaccinated by eye-drop vaccination and in 55 % of chickens vaccinated by the in-contact method. No association was seen between NDV antibody titer at pre-challenge and the ability to withstand B1172 challenge NDV. A fair to good agreement was seen between the HI and ELISA test in monitoring NDV antibody response during the experiment. Although, the ELISA showed a higher sensitivity and specificity than the HI test, further studies are required using this method of comparison. / Dissertation (MMed Vet (Poultry diseases))--University of Pretoria, 2002. / Production Animal Studies / unrestricted

Although Newcastle disease is reported to be endemic in Nigeria, little information exists on the molecular epidemiology and the lineage distribution of the Newcastle disease viruses (NDVs) in the country, especially in the live bird markets. Recent studies reported the identification of three distinct sub-lineages namely; 5f, 5g and 5h in West Africa, particularly sub-lineages 5f and 5g were identified in Nigeria. In this study a total of 41 NDV isolates were analysed. Thirty six NDVs were recovered from a variety of poultry species from live bird markets in the six geo-political zones of Nigeria during active surveillance from 2007 to 2008. Five NDVs recovered from outbreaks in backyard and commercial poultry farms within the same period were also genetically characterized. A commonly used region of the virus genome that spans nucleotide 61 to nucleotide 374 of the Fusion protein, including the cleavage site was targeted. Based on sequence analysis, 39 of the isolates were classified as virulent. Of these, 20 were classified as sub-lineage 5g and 17 were classified as sub-lineage 5f. One isolate differ markedly from all other strains included in the phylogeny. Interestingly, 13 strains from the 5f group formed a distinct cluster that was not identified by other groups in similar studies. Phylogenetic analysis, amino acid sequence determination of the F0 cleavage site sequence analysis, pair wise distance analysis of the partial fusion protein gene sequences and Geographic Information System (GIS) mapping was done. Results showed close genetic similarities and provided evidence for the first time of the epidemiological link between the viruses circulating in the LBMs and those identified in outbreaks in backyard and commercial farms in Nigeria between 2007 and 2008. The emergence and identification of new sub-lineages gives an insight in to the high rate of genetic drift occurring in NDV strains in Nigeria, and raises concerns about the efficacy of current NDV control measures in the country. Thus there is need for continuous surveillance and characterization of NDV from Nigeria to monitor the emergence of new lineages and sub-lineages in the Nigerian poultry industry. Copyright / Dissertation (MSc)--University of Pretoria, 2011. / Production Animal Studies / unrestricted

No description available.

<p> Nd isotope analysis is well suited for mapping major tectonic boundaries in highly metamorphosed orogenic belts. In this study, approximately 80 samples have been analyzed to map 2 such boundaries in the Central Gneiss Belt of the Grenville Province of Ontario. In Central Ontario, lithotectonic terranes with mapped outcrops of gneisses intruded by eclogites and/or coronitic metagabbro have Nd model ages less than 1.8 Ga are interpreted as components of the allochthonous polycylic belt. More northerly terranes are comprised of similar gneissic materials, but have different types of mafic intrusives and have model ages greater than 1. 8 Ga. These terranes are interpreted as fragments of the parautochthonous belt. These two belts are divided by a major thrust, termed the Allochthon Boundary Thrust (ABT) (Rivers, et. al., 1989). Continuing to the north, another step in the Nd model ages has been used to identify and map a cryptic suture between Archean and early Proterozoic crustal materials (Dickin & McNutt, 1989). </p> <p> Along the Georgian Bay coastline, between Pointe Au Baril and Parry Sound, the Shawanaga Shear Zone has been interpreted as the location of the ABT (Culshaw, et. al., 1994). Analysis of over 50 samples are used to map the crustal formation ages in this region and have confirmed this interpretation. Orthogneisses of the Britt Domain have Nd model ages in the range 1.8- 1.9 Ga. Reworking of the original crust has given these rocks U-Pb crystallization ages of~ 1.45 Ga, which means that these rocks have been metamorphosed prior to the Grenvillian event. Crossing the ABT, the orthogneisses of the Shawanaga Domain have a younger range of crustal formation ages, 1.4 - 1.7 Ga. The U-Pb crystallization ages of these rocks are ~ 1.36 Ga, and they lack signs pre-Grenvillian metamorphism. To the south of Franklin Island, the location of the ABT is difficult to map, as outcrop lies beneath the waters of Georgian Bay. Results of the Nd isotope analyses suggest that the ABT passes through the western edge of the Snake Islands, rather than to their east, as previously interpreted (Culshaw, et. al., 1994). </p> <p> Approximately 15 Nd isotope analyses were used to investigate a recently proposed location of the ABT (Ketchum & Davidson, 2000) in the vicinity of the Powassan Batholith. Results from near Arnstein, Restoule and Magnetewan agreed with the existing location of the ABT. To the east of the Powassan Batholith, 3 Nd model ages coupled with a lack of mappable eclogites and/or coronitic metagabbros suggest that earlier interpretations of the position of the ABT may be correct and that further studies in this region are necessary. </p> <p> A cryptic suture identified by crustal formation ages has been the focus of several previous studies (Dickin & McNutt, 1989, 1990; Holmden & Dickin, 1995; Dickin, 1998; Guo & Dickin, 1996). This suture has been mapped from the Georgian Bay coast through Lake Nipissing to the Ontario-Quebec border. New Nd isotope analyses and studies of the regional magnetics have identified a thrust slice between the Grenville Front tectonic zone (GFTZ) and the parautochthonous belt. The cryptic suture appears to coincide with a previously undescribed tectonic boundary west of the Key River. To the west of this boundary, straight orthogneisses within the thrust slice have Nd model ages greater than 2.2 Ga. These differ from the orthogneisses and metaplutonic tonalites to the east of this boundary, which exhibit kilometer-scale isoclinal folds and crustal formation ages between 1.8- 2.0 Ga, the previously identified range for the Britt Domain. </p> <p> Major steps in the depleted mantle model ages are observed in all three regions, allowing mapping of the ABT and the Penokean Suture. It is concluded that, in metamorphic orogenic belts, such as the Grenville Province, detailed mapping of major tectonic boundaries is greatly enhanced by the use of Nd isotope analysis. </p> / Thesis / Master of Science (MSc)

<p> Approximately eighty new neodymium model ages were determined on grey orthogneisses in the Mattawa region of Ontario and were used to develop a Grenvillian tectonic model in the region. A residual-magnetic field map developed from aeromagnetic data provides an additional constraint on the terranes mapped based on Nd-model ages. The field area was divided into three sections: the northern section, the Mattawa klippe, and the southern section. </p> <p> The objectives of mapping in the northern section were two-fold: 1) to map the location of erosional remnants of the allochthon boundary thrust (ABT) and 2) to test the hypothesis that northwestward thrusting of the ABT over the parautochthonous belt caused decollement of a magmatically reworked Archean terrane, creating a duplex thrust sheet and consequent northwestward thrusting of the magmatically reworked Archean parautochthon. </p> <p> Two allochthonous units previously mapped in this region are the Lac Watson nappe and the Lac Booth klippe. These allochthonous units, characterized by Nd-model ages <1.8 Ga are bound by a magmatically reworked Archean terrane (referred to as the reworked Archean parautochthon) with a Nd-model age range of 1.9-2.6 Ga. Likewise, the perimeter of the reworked Archean parautochthon is truncated by a pristine Archean terrane which exclusively hosts Nd-model ages> 2.6 Ga, indicating that there are three crustal stacking levels in the northern section. </p> <p> Nd-model age mapping was employed in the Mattawa klippe region with the same objectives as in the northern section and additionally to provide constraints on the methodology that is to be used when mapping first-order tectonic boundaries such as the ABT. Ketchum and Davidson (2000) suggested that the ABT trended northward in this region based on the presence of 1.16 Ga coronitic metagabbros which Ketchum (1994) concluded were exclusively confined to the allochthonous polycyclic belt (APB). It was detennined here that although the metagabbros are confined to allochthonous crust, based on Nd-model ages, they are contained within an allochthonous klippe (Mattawa klippe) overlying the reworked Archean parautochthon, that transported the coronitic metagabbros northwestward. Therefore, this klippe represents an erosional remnant ofthe APB but the main ABT is located further south. </p> Nd-model age mapping in the southern region identified three distinct crustal terranes. The Mattawa fault was detennined to be a brittle fault following approximately along a pre-Grenvillian suture. This separates the reworked Archean parautochthon from the Paleoproterozoic parautochthon, which had a Nd-model age range from 1.8-1.9 Ga The Paleoproterozoic parautochthon was found to be truncated by the main body of the APB, containing Nd-model ages < 1.8 Ga. The boundary between the Paleoproterozoic parautochthon and the APB was interpreted as the location of the main ABT. </p> <p> Based on the distnbution of Nd-model ages in the region, four distinct crustal terranes were identified representing two thrusting events. Initially the ABT was overthrust on the parautochthonous belt causing decollement of the reworked Archean parautochthon. The entrainment of the reworked Archean parautochthon under the APB generated a duplex thrust sheet, which resulted in the consequent northwestward thrusting of the reworked Archean parautochthon over the pristine Archean terrane. Finally, the ABT was offset by post-Grenvillian normal faulting associated with Ottawa-Bonnechere graben. </p> / Thesis / Master of Science (MSc)

No description available.

Neste trabalho apresentamos uma nova classe de vidros de fluoretos de metais pesados (HMF) baseados nos fluoretos de índio (InF3) de composição InSrBaZnGdNa e InSrBaZnGaNa. Realizamos um estudo das propiredades físicas (tais como: índice de refração, temperaturas características e estabilidades) e óticas (absorção, emissão e tempo de vida) de vidros puros e dopados com Nd ou Pr. As propriedades estão comparadas com aquelas dos vidros ZrBaLaAlNa (ZBLAN). A principal característica dos vidros de fluoretos de índios puros é a extensa transmissão no IV (até 8330 nm), maiores que a do ZBLAN (até 6650 nm). Tanto os vidros dopados com Nd como com Pr são materiais promissores para o desenvolvimento de laser com emissões a 1050 e 1320 nm nos vidros de Nd e a 1320 nm no vidro com Pr e amplificadores óticos para telecomunicações na janela ótica centrada a 1300 nm, uma vez que apresentam bandas de emissão a 1315 nm (InSBZnGdN), 1317 nm (InSBZnGdN:Nd) e a 1320 nm (InSBZnGdN:Pr). / We present a new class of heavy metals fluoride glasses (HMF) of InSrBaZnGdNa and InSrBaZnGaNa compositions. We have realized a study of the physical properties such as refraction index, characteristic temperatures, stability and optical properties such as absorption, emission, lifetime of pure, Nd or Pr doped glasses. These properties are similar to those obtained for glasses of ZrBaLaAlNa (ZBLAN) composition. The main characteristic of pure indium fluoride glasses is their larger transmission window in the infrared region (8330 nm) compared to ZBLAN composition (6650 nm). Rare earth doped glasses are promising materials for the development of glasses laser with emission in the 1050-1320 nm range (Nd) and 1320 nm (Pr), as well as optical amplifiers for telecommunication in the optical window centered at 1300 nm, as prominent emission bands are located at 1315 nm (InSBZnGdN), 1317 nm (InSBZnGdN:Nd) and 1320 nm (InSBZnGdN:Pr).

O entendimento das interações de ultralongo alcance envolvendo átomos de Ryberg frios é o ponto principal para o uso deste sistema em computação quântica. Neste trabalho estudamos tais interações envolvendo estados nD+nD em um novo aparato experimental, o qual permite o controle de campo elétrico de uma forma mais eficiente. Mais especificamente estudamos o processo colisional $nD + nD$ $ightarrow$ $(n+2)P + (n-2)F$ na presença de campo elétrico estático fixo. Este processo é importante porque pode levar a decoerência da amostra. Os resultados obtidos indicam a existência de uma ressonância molecular que é sensível ao efeito Stark. Além disso, investigamos se o movimento atômico é importante para popular tais estados. Por fim, proporemos novos experimentos que podem ser úteis para controlar e suprimir tais processos colisionais e assim permitir avanços na área de computação quântica com tais sistemas. / The understanding of ultralong-range interaction involving cold Rydberg atoms is the main step for use this system in quantum computation. In this work, we have studied interaction involving $nD$ states in a new experimental setup, which allows us to control the electric field in a more efficient way. More specifically, we have studied the collision process $nD + nD ightarrow (n+2)P + (n-2)F$ in the presence of a static electric field. This process is important because it can lead to a decoherence of the sample. The observed results show the existence of a molecular resonance which is dependent of Stark effect. Moreover, the atomic motion is perhaps also important to populate such states. Finally, we propose new experiments that can be useful to control and to suppress theses colisional processes and in this way allows us to move on in quantum computing area with such systems.

[pt] Enquanto aumenta o uso da sustentabilidade nos projetos urbanos, cresce a necessidade de se elaborar indicadores de sustentabilidade que sirvam como referência para avaliar as políticas urbanas implantadas na cidade. Com isso surgem novos sistemas de avaliação que levam em consideração o entorno, a localização, a mobilidade urbana, a infraestrutura e a gestão ambiental, colocando em prática conceitos do novo urbanismo e desenvolvimento sustentável. Através de indicadores qualitativos de sustentabilidade, mostra-se como as cidades poderiam ser pensadas para absorver o crescimento urbano, sem deixarem de ser autossustentáveis, oferecendo oportunidades sem colocar em risco as gerações futuras. Após um levantamento dos parâmetros conceituais urbanos de sustentabilidade, foi elaborado um estudo de caso do loteamento Centro Metropolitano, localizado na Barra da Tijuca, indicando a sua possibilidade de certificação de acordo com os padrões exigidos pela certificação LEED ND (Leadership in Energy and Environmental Design Neighborhood Development). / [en] The terms Sustainable Neighborhoods or Green Neighborhoods have been increasingly used by society as a positive way to occupy new areas. This concern for the sustainable development of cities has meant that developers across the country to adhere to this thought, seeking certification as a way to classify their projects at different levels of sustainability and add value to their works (FARR, 2013). Currently there are numerous enterprises certified and in process of certification in the country. However, environmental certification for neighborhoods has not been much discussed and used in Brazil. While the use of sustainability increases in urban projects, it grows the need to develop sustainability indicators that serve as a reference for assessing urban policies implemented in the city. What can be seen nowadays is an urban legislation where the indices for construction differ from the indices required by environmental certifications, and therefore require a compatibility of urban laws with environmental certifications, enabling thus a sustainable urban growth of neighborhoods (FARR, 2013). The main problem of this research is: what would be the best way to measure sustainability in urban settlements. The indicators are fully applicable to the Brazilian urban environment? The construction is major cause of degradation in the environment. Thus it justifies the choice of this subject, as an attempt to gather information and data to encourage the construction of neighborhoods that cause less environmental impacts. The overall objective of this research consist of listing sustainability indicators for urban neighborhoods and housing developments, which are in accordance with the law of Rio de Janeiro and the local reality. The methodology adopted for this study consist of the following stages of research: conceptualize the term urban sustainability; describe indicators with essential importance to enable sustainable urban development; list the most used and recognized environmental certifications for neighborhoods; analyze the LEED ND certification; analyze and apply the concepts of LEED ND in the study subdivision.

Les Evénements Océaniques Anoxiques (OAE) sont des événements extrêmes qui se sont pro- duits majoritairement durant le Crétacé et qui sont caractérisés par un enfouissement massif et brutal de carbone organique. Ces événements ont été très étudiés durant ces 40 dernières années mais aucun consensus n’a été atteint quand aux processus à l’origine de leur déclenchement. Pour tenter de répondre aux questions encore en suspens, nous avons réalisé une étude géochimique approfondie (éléments majeurs et traces, compositions isotopiques en Nd et Hf) des différentes fractions (détritiques et authigènes) de sédiments marins déposés lors de l’événement océanique anoxique associé à la limite Cénomanien-Turonien (OAE2, 93.5Ma). Les deux sections étudiées représentent différents environnements de dépôt : un environnement peu profond et proche des sources continentales (Taghazoute, Maroc) et un environnement marin profond, loin des côtes (DSDP Site 367, Cap-Vert).A l’approche de l’OAE2, les compositions isotopiques du Nd et de l’Hf ne présentent que peu de variations. Ces observations reflètent une absence de changement dans le régime d’érosion continentale en amont des deux sections étudiées. Notre étude diverge du scenario proposant qu’un fort apport de nutriments résultant d’une altération continentale accrue soit à l’origine des OAEs. En revanche, les variations isotopiques (Nd) mesurées dans les fractions authigènes du Site 367, interprétées comme reflétant la composition océanique passée, supportent l’idée d’une contribution magmatique dans l’Océan Atlantique durant l’OAE2. Ces nouveaux résultats sont cohérents avec de précédentes études et confortent le rôle des grandes provinces magmatiques (plateau des Caraïbes) dans l’eutrophisation des océans qui précède les événements anoxiques.En outre, l’étude combinée des terres rares (REE) et des compositions isotopiques (Nd) de fractions authigènes obtenues par extraction chimique (leaching) démontre l’incorporation de matériel détritique dans ces fractions en milieu peu profond. Ces nouvelles observations questionnent l’idée que toute fraction authigène enregistre une composition chimique océanique pure. Enfin, l’étude complète des concentrations en éléments traces de ces mêmes fractions souligne le rôle important de la lithologie des sédiments sur la composition des leachates. Cette étude questionne également l’utilisation de certaines méthodes de leaching qui semblent favoriser l’extraction de phases détritiques externes lorsque les sédiments sont soumis à des étapes de leaching répétées. / Oceanic Anoxic Events (OAE) are brief and extreme events that mostly occurred during the Cretaceous and are defined by the burial of massive amounts of organic carbon. These events have been intensely investigated in the last 40 years but the mechanism that triggered OAEs remains problematic. In order to better constrain what causes these events, we realised a complete geochemical study (major and trace elements, isotopic compositions of Nf and Hf) of various sedimentary fractions (detrital and authigenic) for marine sediments associated with the Cenomanian-Turonian boundary event or OAE2 (93.5 Ma). We focused our study on two marine sections that represent different depositional settings : a shallow marine setting, close to the continental shelf (Taghazoute, Morocco) and a abyssal marine section (DSDP Site 367, Cape-Verde), far from the African shelf.The remarkable stability of the Nd-Hf decoupling in both sections indicates no obvious change of continental weathering approaching OAE2. Our conclusions diverge from the hypothesis that proposes an higher nutrient input through an enhanced continental weathering as a triggering mechanism of OAEs. However, Nd isotopic compositions of authigenic fractions measured at Site 367, interpreted as past oceanic composition, exhibit a positive isotopic excursion and indicate a magmatic contribution in the deep Atlantic Ocean during OAE2. These new data are consistent with previous isotopic studies and support the role of Large Igneous Province (in our case, the Caribbean Plateau) as nutrient provider and triggering mechanism of anoxic events.The combined study of rare earth elements (REE) and Nd isotopic compositions of authigenic fractions recovered by leaching demonstrates the incorporation of detrital material in authigenic fractions in shallow marine settings. These new results challenge the traditional belief that authigenic material always records an untouched seawater composition. Finally, the extensive study of trace element concentrations of these same fractions demonstrated the strong impact of sample lithology on their trace element content. Our study also questions the relevance of sequential leaching methods that facilitate external contamination when sediments are submitted to repeated leaching steps.