Tesis por compendio / ‘Candidatus Liberibacter solanacearum’ is a α-Proteo bacteria, Gram-negative, restricted to plant phloem and to the haemolymph of psyllids that act as vectors. This emerging bacterium has been associated with different diseases in different hosts and associated with carrot (Daucus carota) in Spain. Vegetative disorders of unknown etiology have also been observed in celery (Apium graveolens) since 2008. A real-time PCR protocol specific to ‘Ca. L. solanacearum’ detection, using TaqMan probe and direct sample preparation methods have been developed. This technology has been validated in an intra-laboratory study (sensitivity 1, specificity 1 and accuracy 100%) and is available commercially as a complete kit. It has been demonstrated that ‘Ca. L. solanacearum’ is associated with the observed syndrome in celery and a new bacterium haplotype (E) has been identified. With these results it is concluded that celery is a new host of ‘Ca. L. solanacearum’ (Teresani et al., 2014a). Using the newly developed real-time PCR protocol ‘Ca. L. solanacearum’ has been detected in 42,6% of the carrot seeds lots tested and in individual seeds. The number of cells/seeds has been estimated in 4.8±3.3 to 210±6.7, which only 5% were viable. After 150 days post-germination, 12% of seedlings showed symptoms and tested positive for ‘Ca. L. solanacearum’. Liberibacter-like cells were observed in the phloem sieve elements of the seed coat and in the phloem of carrot leaf midrib from seedlings. These results demonstrated that ‘Ca. L. solanacearum’ is transmitted by carrot seeds (Bertolini et al., 2014b). The collected arthropods were classified into families, and the superfamily Psylloidea was identified to the species level resulting Bactericera trigonica, B. tremblayi and B. nigricornis the main identified species. The population dynamics of different psyllids species visiting carrot, celery and potato has been determined, concluding that the highest populations are captured during summer. The bacterium has been detected in the different Bactericera species previous cited additionally to Bactericera sp. The psyllid species carrying the bacteria can be considered as possible vectors of the bacterium (Teresani et al. 2014b). Electrical Penetration Graphs showed that B. trigonica was able to feed in the phloem of carrot, celery and potato but not in the phloem of tomato plants. Experimental transmission showed that B. trigonica transmitted ‘Ca. L. solanacearum’ from carrot to carrot, celery, potato and tomato. More efficient transmission occurred with ten individuals, and the transmission rates were 100% in celery, 80% in carrot and 10% in potato and tomato. The experimental transmission to potatoes threatens this crop (Teresani et al., 2014c). These combined results have built a scientific foundation of the biological and epidemiological aspects of ‘Ca. L. solanacearum’ contributing to new scientific information that is key in cultivation of celery and carrot to establish bacteria control strategies. The use of bacteria-free carrot seed lots will definitely contribute to mitigate damage and reduce risks of transmission to solanaceous crops. / Ribeiro Teresani, G. (2014). Candidatus Liberibacter solanacearum: detection, characterization, new hosts and epidemiology in Spain [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/48459 / Compendio

El presente proyecto de investigación tiene como finalidad el diseño de una planta productora de goma de algarroba para su exportación que permita el aprovechamiento de la gran extensión de algarrobos en el Perú, que pueda brindar una opción sostenible en el tiempo y que a la vez traiga mayores beneficios dándole un mayor valor agregado y tenga mayor acogida en el mercado internacional. Para ello, se busca determinar su viabilidad, específicamente, la viabilidad comercial, técnico-tecnológica y económico-financiera. Para ello se realizó un estudio de mercado, en el cual, se evaluaron a los 5 primeros países importadores de goma de algarroba, donde se obtuvo a Alemania como mercado idóneo para satisfacer su demanda. Se busca, además, aprovechar la disponibilidad de algarroba de Lambayeque, obteniéndose a Olmos como localización estratégica para la planta, sobre todo por la cercanía a la materia prima, los bosques secos de Olmos abastecerán a la planta para una producción de 52 417 sacos de goma de algarroba para el primer año. Por último, de acuerdo al análisis económico-financiero para confirmar su viabilidad, se requiere una inversión de $ 3 166 965,49 en total, recuperándose en el año 2 con un VAN de $ 767 402,29 y una TIR de 38,94% confirmando su viabilidad. / The purpose of this research project is to design a carob gum production plant for export, aiming to utilize the vast expanse of carob trees in Peru. The goal is to provide a sustainable option that brings greater benefits by adding more value and gaining wider acceptance in the international market. To achieve this, the project aims to determine its viability, specifically the commercial, technical-technological, and economic-financial viability. A market study was conducted, evaluating the top 5 importing countries of carob gum, identifying Germany as the ideal market to meet its demand. Additionally, the project seeks to take advantage of the availability of carob in Lambayeque, with Olmos being identified as a strategic location for the plant due to its proximity to the raw material. The dry forests of Olmos will supply the plant, enabling a production of 52,417 sacks of carob gum in the first year. Finally, according to the economic-financial analysis to confirm its viability, a total investment of $3,166,965.49 is required, which will be recovered by the second year with a net present value (NPV) of $767,402.29 and an internal rate of return (IRR) of 38.94%, confirming its viability.

No / Intensive research in bio-engineering has been conducted in the search for flexible biomaterials that could support cell growth and cells attachment. Flexible synthetic materials that support cell growth without the aid of synthetic extracellular matrix proteins are still rare. Cholesteryl liquid crystal containing cholesteryl moieties may have suitable biological affinity. Human keratinocytes (HaCat) were cultured with a nematic liquid crystal and three cholesteryl liquid crystals of different formulation. Subsequently, the trypan blue dye exclusion assay was used to determine cell viability in the liquid crystals. The two classes of liquid crystal were characterized by Differential Scanning Calorimeter (DSC) and polarizing microscope (POM) to understand the nature of the interface material. The cell viability study in medium containing liquid crystals verified that liquid crystals had no effects on cell viability. However, only the surface of cholesteryl liquid crystal has shown affinity to HaCat cells. In addition, cells continued to proliferate in the presence of liquid crystals without a change of medium for eight days. No sign of exothermic and endothermic activities at 370C were observed from the DSC test results for the three samples. Biological and mechanical test result of the cholesteryl liquid crystals has shown that cholesteryl liquid crystals are non toxic and support cell attachment without extracellular matrix protein at very low elasticity.

Increased temperatures due to anthropogenic-induced climate change may raise the threat of extinction for taxa with sessile life histories (e.g., plants) in the near future. Linking climate change models to demographic models may provide useful insights into the potential effects of environmental changes on rare plants, and therefore aid in their current and future conservation. Population demographers generally agree that mechanistic models from a reductionist perspective are necessary to test assumptions in population drivers. For the first study, I assessed the climate vulnerability of a rare plant species, Pyrrocoma radiata, with a mechanistic model of four climatically-similar populations. I used environmentally-driven demographic models to estimate vital rates and population sizes from a nonlinear, nonparametric regression with local climate variables. I assessed the utility of this environmentally-correlated, stage-structured population matrix model compared to a stationary model of independent and identically-distributed environmental stochasticity. I then simulated future population projections based on climate conditions predicted by General Circulation Models (GCMs) under opposing emission scenarios. The second study hopes to answer population-level questions using a traditionally community-level method, non-metric multidimensional scaling, which considers correlation structure between response variables and can be used to find environmental correlates of the ordination axes. Demographic data on a threatened perennial, Astragalus tyghensis, were collected from five sites in the Tygh Valley, OR. I considered correlation structure between demographic vital rates to find environmental correlates of the ordination axes. The search for an environmental driver of population vital rates was successful for the two study species. Previous year dry dormant season precipitation likely affects the fertility rates a year later in P. radiata populations, and dry growing season reference evapotranspiration rates positively correlated with a growth gradient in A. tyghensis. Based on predicted precipitation, P. radiata is expected to rapidly decline by 2050, but this may be due to biases in the two GCMs and reliance on only one environmental factor. The NMS ordination adequately captured most of the variation in transition elements for the years and populations from A. tyghensis demographics. I provided support to the claim that model predictions can improve with the inclusion of mechanistic relationships. The inclusion of abiotic drivers in models used to predict population trends is supported by our study and may enhance predictive power in population viability assessments under changing climates. / Graduation date: 2013

Thesis (M. Tech. Agriculture) -- Central University of Technology, Free state, 2012 / A series of incubation studies and greenhouse experiments were conducted to evaluate the use of EM seed treatments, at different application levels, handling techniques and soil conditions on germination and seedling vigour of selected cultivars of maize, sorghum and sunflower. Two incubation studies were conducted to evaluate the germination and seedling vigour of maize, sorghum and sunflower seeds treated with M-EM from three different suppliers, multiplied at two different ratios (1% and 3%) and diluted at three different levels (0.01%, 0.1% and 1.0%) compared to a control treated with pure water. Results revealed no significant differences under optimum germination conditions, while seedlings under cold stress indicated that M-EM treatments positively affected germination and seedling vigour compared to the control treatments. Two incubation studies were also conducted to evaluate the germination and seedling vigour of maize, sorghum and sunflower seeds treated with M-EM from three different suppliers, multiplied at two different ratios (1% and 3%) and exposed to the influences of irradiation and temperature fluctuation. From the results became clear that the correct storage and handling is essential in optimizing the effect of M-EM on seeds. Even though M-EM was exposed to irradiation and temperature fluctuation, M-EM still had positive effects on germination and seedling vigour. Pot experiments were conducted to determine the effect of EM as seed treatment, at different dilutions, on germination, seedling vigour and dry mass of maize, sorghum and sunflower at different planted depths. Germination were not affected by the M-EM treatment, while shoot length results indicated that seed treated with M-EM could have significant effect on seedling survival. A greater effect was visible on the shoot length of shallow planted seeds, than on deeper planted seeds. From the results no single company, ratio or dilution could be prescribed as paramount. To further investigate the effect of M-EM subjected to the influences of irradiation and temperature fluctuation; maize, sorghum and sunflower seeds were treated with M-EM from three different suppliers, multiplied at two different ratios (1% and 3%) and exposed to the influences of irradiation and temperature fluctuation and planted in soil. M-EM treatments only benefited the germination of deeper planted sorghum seeds compared to the control treatments. The shoot lengths of deeper planted maize and sunflower seed were positively increased by the M-EM treatments while also resulting in significant results for the overall shoot length of sorghum. The third pot study was conducted to determine the influence of EM as a seed treatment on maize, sorghum and sunflower planted in three different soils, namely: sterilized soil, soil treated with M-EM and Fusarium containing soil. Germination and seedling vigour results of the sterilized and M-EM treated soil revealed to be superior to that of the Fusarium containing soil. From the results was concluded that M-EM treatments will probably improve early seedling growth of maize, sorghum and sunflower compared to untreated seed and that M-EM seed treatment and a pre-plant EM soil treatment might assist seeds in unfavourable germination and growth conditions.

No description available.

In view of the increasing global challenge of bacterial resistance, there exists an urgent need for the rationale development of antibacterial compounds with either novel or multiple mechanisms of action. Two chalcone-derivatives, F1 and F23, demonstrated MICs within the range of 16 to >512 μg/ml against two plant pathogens (P. caratovoram and C. michiganensis subsp. michiganensis) as well as important clinical bacterial species. Both compounds displayed an MIC of 32 μg/ml against quinolone-resistant S. aureus. Whilst possessing weak activities individually, each semi-synthetic agent displayed notable synergistic action with polymyxin B against S. aureus, C. violaceum, E. coli and Ps. aeruginosa, thereby recording FICs within the range of <0.093 to 2 that indicated the existence of synergism in some instance. These chalcone compounds applied with polymyxin B displayed a notable FICindex of <0.093 against the Neisseriaceae C. violaceum, and a potential noteworthy capacity to extend the spectrum of activity of the latter antibiotic to include Gram-positive S. aureus species. F1 inhibited staphylococcal replication in broth and the combination of either of both chalcone-derivatives with polymyxin B instituted a metabolic blockage in S. aureus and other bacterial species as determined through a modified MTT reduction assay. The combined agents inflicted major disruptions to the S. aureus cytoplasmic membrane bilayer as evidenced by the release of intracellular potassium as well as the influx of Sytox Green fluorescent stain. Notable levels of cell membrane potential dissipation, leakage of intracellular potassium ions and blockage of reducing enzymes activities occurred within the first 30 minutes, well in advance of significant loss in cell viability that was recorded usually after 4 – 8 hours, suggesting these activities were prerequisites to cell death. In erythrocyte lysis assay, the synergistic combinations of 128 μg/ml of either of both chalcone derivatives with 128 μg/ml polymyxin B displayed the lowest degree of haemolysis, followed by that occurring with 32 μg/ml of the chalcone-derivatives combined with 256 μg/ml of the polypeptide antibiotic. In conclusion, further structure activity modifications aimed at improving the aqueous solubility of these chalcone-derivatives as well as the antibacterial activity recorded for certain combination concentrations of polymyxin B with either of these semi-synthetic agents may be required before considerations are made for the possibility for potential external formulations. Such preparations may include antiseptic creams, lotions, ointments, as well as aerosols that can be applied with nebulizers in targeted delivery for such cases like cystic fibrosis.

The critically endangered blue-eyed black lemur (Eulemur flavifrons) is one the leaststudied day active lemurs because of the recent rediscovery and limited distribution. This thesis examined the habitat use, reproductive parameters and the population viability of the blue-eyed black lemur population at Ankarafa Forest, Sahamalaza-Iles Radama National Park, Madagascar. The main aim was to gather fundamental information on the natural history of the blue-eyed black lemur and to propose conservation approaches for both the species and its habitat. Data were collected over 14 month-period between 2006 and 2008. Six groups of the blue-eyed black lemur were studied, four of which were collared and two uncollared. Ankarafa Forest, the largest forest blocks of the Sahamalaza-Iles Radama National Park, is dominated mainly by Mangifera indica, Garcinia pauciflora, Sorindeia madagascariensis, Grangeria porosa, Bambou sp. and Mascarenhasia arborescens species. The forest is vulnerable to degradation by both anthropogenic activities and abiotic factors. The population density of the blue-eyed black lemur at Akarafa Forest was estimated to be 97.3 individuals km-², with group size ranging from 4 to 11 individuals. The home range use and day path length of the blue-eyed black lemur varied seasonally. The lemur occupied a larger home range in the dry season than in the wet season. The age of first reproduction in the blue-eyed black lemurs is about 3 years. They bear offspring seasonally (late August-October), all adult females in groups bred and females produce singletons offspring. Females were dominant over males. The sex-ratio at birth was male-biased but not significantly different from 1:1. Females were the primary caretakers of infants but group members other than the mother also provided alloparental care. For the first 3 weeks of life, infants were carried constantly on their mothers’ bellies. Infants developed independent locomotion and fed on solid food by 10 weeks. Increased probability of extinction, as shown by population viability models of the blue-eyed black lemur population, is affected by various of their reproductive parameters. However, these do not account for changes in their primary habitat forest. The latter is under increased human pressure and continues to decline in area. Education awareness and community involvement are required if the habitat and the blue-eyed black lemur are to survive. Findings of this study serve not only important data to understand the life history of the blue-eyed black lemur but also suggest conservation approaches for both the species and its natural habitat. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2009.

Nous avons identifié l’expression du récepteur des angiopoïétines, le récepteur Tie2, à la surface des neutrophiles humains. De plus, nous avons démontré qu’Ang1 et Ang2 induisent des activités pro-inflammatoires sur les neutrophiles, comme l’adhésion aux cellules endothéliales (CEs) et la synthèse du facteur d’activation plaquettaire (PAF). Puisque le PAF augmente la viabilité des neutrophiles et que les angiopoïétines modulent la survie des CEs, nous avons voulu évaluer l’effet des angiopoïétines sur la survie des neutrophiles. Des neutrophiles humains ont été isolés à partir du sang de donneurs sains en accord avec le comité d’éthique de l’Institut de cardiologie de Montréal. La viabilité des neutrophiles a été mesurée par cytométrie en flux à l’aide de marqueurs d’apoptose et de nécrose. Un traitement avec des témoins positifs, soit l’interleukine 8 (IL-8; 25 nM) ou le PAF (100 nM), a augmenté la survie basale des neutrophiles de 34 et 27%, respectivement. De plus, un traitement avec Ang1 (1 pM – 10 nM) a augmenté la survie des neutrophiles jusqu’à 35%, alors qu’Ang2 n’a eu aucun effet. La combinaison de l’IL-8 ou du PAF avec Ang1 (10 nM) a eu un effet additif sur la viabilité des neutrophiles et a augmenté la survie de 56 et 60%, respectivement. Un prétraitement avec des anticorps bloquants contre l’IL-8 a permis d’inhiber l’activité anti-apoptotique de l’IL-8 et d’Ang1 de 92 et 80%, respectivement. Ainsi, notre étude est la première à démontrer la capacité d’Ang1 à prolonger la viabilité des neutrophiles, qui est principalement causée par la relâche d’IL-8. / We reported the expression of angiopoietin receptor Tie2 on the surface of human neutrophils. In addition, we reported that Ang1 and Ang2 are both capable to promote pro-inflammatory activities in neutrophils, namely their adhesion onto endothelial cells (ECs) and platelet-activating factor (PAF) synthesis. PAF is known to promote pro-survival activity on neutrophils and since both angiopoietins can modulate ECs viability, we addressed whether Ang1 and/or Ang2 could modulate neutrophil viability. Human neutrophils were isolated from blood of healthy volunteers in accordance with the guidelines of the Montreal Heart Institute’s ethical committee. Neutrophil viability was assessed by flow cytometry using apoptotic and necrotic markers. Treatment with anti-apoptotic mediators such as interleukin 8 (IL-8; 25 nM) and PAF (100 nM) increased neutrophil basal viability by 34 and 27%, respectively. In addition, treatment with Ang1 (1 pM – 10 nM) increased neutrophil viability by up to 35%, while Ang2 had no effect. Combination of IL-8 or PAF with Ang1 (10 nM) provided an additive effect on neutrophil viability and further increased viability by 56 and 60%, respectively. Pretreatment of the neutrophils with blocking anti-IL-8 antibodies inhibited the anti-apoptotic effect of IL-8 and Ang1 by 92 and 80%, respectively. In summary, our data are the first one to report Ang1 pro-survival activity on neutrophils, which is mainly driven through IL-8 release.

Orientador: Guilherme Wolff Bueno / Resumo: O aumento exponencial da população em nível mundial tem crescido a demanda por proteínas de qualidade. Com isto, muitos produtores rurais têm migrado da atividade agrícola para a aquicultura, surgindo propriedades com diferentes níveis de produção de pescado. No entanto, com o desconhecimento das especificidades econômicas e zootécnicas, vários empreendimentos se tornaram insustentáveis economicamente, gerando endividamentos e falência dos negócios. Neste contexto, o objetivo desta pesquisa consistiu em realizar uma modelagem financeira e avaliar o risco econômico da produção comercial de tilápia (Oreochromis niloticus) em sistema de tanques-rede instalados em um reservatório tropical. O estudo é apresentado em dois capítulos, no primeiro avaliamos o risco financeiro e cenários econômicos de fazendas com grandes volumes de produção (VP), áreas aquícolas de 10 a 600 mil m³. No segundo capitulo, a partir das informações obtidas inicialmente desenvolvemos um modelo matemático de predição financeira (MMPF) integrado com o modelo matemático do coeficiente de crescimento térmico (TGC) o qual considerou variáveis de desempenho dos peixes e fatores econômicos da produção. Verificamos que os tanques-rede com volumes superiores a 51 mil m³ apresentam 38,67% de probabilidade de risco financeiro e econômico, com um Payback acima de 10 anos e podem atingir um Valor Presente Líquido (VPL) maior que zero com uma taxa interna de retorno (TIR) menor que 8,67%. Enquanto, fazendas com área infe... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The exponential increase in population worldwide has been growing the demand for quality proteins. As a result, many farmers have migrated their agricultural to aquaculture, in this scenario the fish farms have different levels of scale production. However, the lack of knowledge of fish production and economic conditions, was promoted enterprises economically unsustainable, generating indebtedness and business failure. In this context, the objective of research was to perform a financial modeling and evaluate the economic risk of commercial production Nile tilapia (Oreochromis niloticus) in the cages installed in a tropical reservoir. The study is presented in two chapters. In the first chapter we assess the financial risk and economic scenarios of fish farms with large production volumes (VP), aquaculture areas from 10 to 600 thousand m³. In a second chapter, we used the information obtained from 1th chapter for developed a mathematical model for financial prediction (MMPF) integrated with the thermal growth coefficient mathematical model (TGC) considered fish performance variables and economic factors to tilapia production. We verified that cages with volumes over 51,000 m³ have a 38.67% probability to lower financial and economic risk, obtain a payback over 10 years and result a net present value (NPV) greater than zero with an internal rate of return (IRR) of less than 8.67%. Likewise, fish farms with area of less 50,000 m³ have a 51.17% the probability of financial failu... (Complete abstract click electronic access below) / Mestre