Reported in this dissertation are the results of investigations performed at the New Orleans Center for Mass Spectrometry at the University of New Orleans. The projects that are detailed in the coming pages take on a variety of subjects, but a common thread is that each employs matrix-assisted laser desorption/ionization (MALDI) mass spectrometry to solve a problem. Fundamental aspects of MALDI in-plume ionization are implicated in the introduction of a newly developed electron-transfer secondary ionization matrix. The remaining projects are related to the ever expanding field of proteomics. Mass spectrometry was used to investigate the site specificity of a newly developed bilin-lyase enzyme, a new approach was developed to distinguish between A-ring and D-ring attachment of bilins, and F. grandis protein expression pattern was investigated in several tissues. All obtained results were acquired using a MALDI TOF/TOF mass spectrometer. The sensitivity, mass accuracy, mass resolution and the ability to perform collision induced decomposition (CID) experiments were all valuable features that served to raise the quality of data, and thereby improved the detail of inferences to be drawn for the different projects.

O gênero Acacia apresenta espécies florestais de rápido crescimento, com rotações curtas (7 a 9 anos) e de grande interesse comercial para produção de polpa celulósica, painéis de madeira e energia. No Brasil a utilização de espécies do gênero Acacia na produção de celulose de fibra curta ainda é bastante restrita e são poucos os estudos que demonstram a potencialidade do uso dessa matéria-prima para a obtenção de polpa celulósica com as propriedades alcançadas pelas espécies do gênero Eucalyptus. Este trabalho teve como objetivo analisar o potencial de algumas espécies do gênero Acacia (A.aulacocarpa, A. auriculiformis, A. crassicarpa, A. mangium) plantados no Brasil, para a produção de polpa celulósica Kraft, considerando os aspectos relacionados à qualidade da madeira e da polpa, o consumo de reagentes químicos na polpação e também os aspectos relacionados ao rendimento e a capacidade de produção de polpa celulósica; adicionalmente buscou-se fornecer informações estratégicas para o setor celulósico nacional com relação as possíveis ameaças e as oportunidades apresentadas pelos materiais não utilizados no Brasil. Para realização deste trabalho foram utilizados 11 materiais genéticos distintos e cada um dos materiais genéticos foi considerado um tratamento e todos com 5 anos de idade. As características avaliadas foram: densidade básica, dimensões das fibras, composição química e parâmetros da polpação kraft (rendimento bruto, rendimento depurado, teor de rejeitos, número kappa e relações). Para este último objetivo, as madeiras de cada uma das espécies foram submetidas ao processo de polpação kraft, considerando-se seis níveis de álcali ativo: 18,0; 19,5; 21,0; 22,5; 24,0 e 25,5%, mantendo-se constantes as outras variáveis de cozimento. Observou-se que o modelo de variação longitudinal para densidade básica da árvore mantém uma tendência dos valores serem mais elevados na base e valores mínimos entre 25 e 50% da altura comercial. Quanto à composição química os valores foram distintos para todas as espécies e apresentaram uma variação de 60,99% para A. auriculiformis (1) e 68,79% para A. aulacocarpa (1) como valores mínimo e máximo. Os resultados obtidos quanto às dimensões das fibras não apresentaram padrões definidos de variação entre as espécies. Notou-se quanto aos parâmetros da polpação um efeito diferenciado entre as espécies de Acacia para as distintas cargas de álcali ativo. Considerando a curva de polpação para obtenção de número kappa 18 entre as espécies estudadas, obteve-se como média para a demanda carga de alcalina 23,8% e a média do rendimento depurado nestas condições foi 54,72%. A espécie A. crassicarpa procedência (1) destacou-se por apresentar a maior conversão em massa (ton/ha) de madeira na produção de celulose e a A. mangium procedências (1, 2, 3 e principalmente 4) alcançaram os melhores resultados de rendimento frente ao processo kraft de polpação comparando toas as espécies deste estudo. / The genus Acacia includes fast-growing short-rotation (7 to 9 years) forest tree species of commercial interest to produce pulp, wood panels, and energy. In Brazil, the utilization of species of the genus Acacia to produce short fiber pulp is still highly restricted and few studies are available that demonstrate the potential use of this raw material to obtain pulp presenting the properties displayed by species of the genus Eucalyptus. This study aimed at analyzing the potential of some species of the genus Acacia (A. aulacocarpa, A. auriculiformis, A. crassicarpa, A. mangium) planted in Brazil to produce kraft pulp, considering the aspects related to wood and pulp quality, consumption of chemical reagents during the pulping process, yield, and cellulose pulp production capacity. Furthermore, this work searched for strategical information for the national pulp and paper sector as to possible threats and opportunities presented by materials not used in Brazil in order to provide knowledge and discuss the potential competitiveness of these types of wood in the world market for pulp and paper. To accomplish these goals, we used 11 5-year-old distinct genetic materials, each one of them considered a different treatment. The following traits were evaluated: basic density, longitudinal variation, fiber dimensions, chemical composition, and kraft pulping process parameters (total yield, screened yield, rejects content, kappa number and relations). To carry out these evaluations, each wood species underwent the kraft pulping process considering six levels of active alkalis: 18.0, 19.5, 21.0, 22.5, 24.0, and 25.5%, keeping all other cooking variables constant. We observed that the model of longitudinal variation in the basic density maintains the trend of reaching higher values in the base of the tree and minimum values between 25% and 50% of the commercial height. The values found for the chemical composition were different for all the species studied and the holocellulose content ranged from a minimum of 60.99% found for A. auriculiformis (1) to a maximum of 68.79% found for A. aulacocarpa (1). The results obtained for fiber dimensions did not present defined patterns of variation among the species. The kraft pulping process parameters showed differences among Acacia species for the distinct levels of active alkalis. Considering the pulping process curve to get the kappa number of 18 among the species studied, the average alkali demand was 23.8% and the average depurated yield under these conditions was 54.72%. A. crassicarpa procedure 1 presented the highest conversion into wood mass (t/ha) to produce cellulose and A. mangium procedures (1, 2, 3, and mainly 4) reached the best results in terms of yield when they underwent the kraft pulping process compared to all the species studied herein.

O gênero Acacia apresenta espécies florestais de rápido crescimento, com rotações curtas (7 a 9 anos) e de grande interesse comercial para produção de polpa celulósica, painéis de madeira e energia. No Brasil a utilização de espécies do gênero Acacia na produção de celulose de fibra curta ainda é bastante restrita e são poucos os estudos que demonstram a potencialidade do uso dessa matéria-prima para a obtenção de polpa celulósica com as propriedades alcançadas pelas espécies do gênero Eucalyptus. Este trabalho teve como objetivo analisar o potencial de algumas espécies do gênero Acacia (A.aulacocarpa, A. auriculiformis, A. crassicarpa, A. mangium) plantados no Brasil, para a produção de polpa celulósica Kraft, considerando os aspectos relacionados à qualidade da madeira e da polpa, o consumo de reagentes químicos na polpação e também os aspectos relacionados ao rendimento e a capacidade de produção de polpa celulósica; adicionalmente buscou-se fornecer informações estratégicas para o setor celulósico nacional com relação as possíveis ameaças e as oportunidades apresentadas pelos materiais não utilizados no Brasil. Para realização deste trabalho foram utilizados 11 materiais genéticos distintos e cada um dos materiais genéticos foi considerado um tratamento e todos com 5 anos de idade. As características avaliadas foram: densidade básica, dimensões das fibras, composição química e parâmetros da polpação kraft (rendimento bruto, rendimento depurado, teor de rejeitos, número kappa e relações). Para este último objetivo, as madeiras de cada uma das espécies foram submetidas ao processo de polpação kraft, considerando-se seis níveis de álcali ativo: 18,0; 19,5; 21,0; 22,5; 24,0 e 25,5%, mantendo-se constantes as outras variáveis de cozimento. Observou-se que o modelo de variação longitudinal para densidade básica da árvore mantém uma tendência dos valores serem mais elevados na base e valores mínimos entre 25 e 50% da altura comercial. Quanto à composição química os valores foram distintos para todas as espécies e apresentaram uma variação de 60,99% para A. auriculiformis (1) e 68,79% para A. aulacocarpa (1) como valores mínimo e máximo. Os resultados obtidos quanto às dimensões das fibras não apresentaram padrões definidos de variação entre as espécies. Notou-se quanto aos parâmetros da polpação um efeito diferenciado entre as espécies de Acacia para as distintas cargas de álcali ativo. Considerando a curva de polpação para obtenção de número kappa 18 entre as espécies estudadas, obteve-se como média para a demanda carga de alcalina 23,8% e a média do rendimento depurado nestas condições foi 54,72%. A espécie A. crassicarpa procedência (1) destacou-se por apresentar a maior conversão em massa (ton/ha) de madeira na produção de celulose e a A. mangium procedências (1, 2, 3 e principalmente 4) alcançaram os melhores resultados de rendimento frente ao processo kraft de polpação comparando toas as espécies deste estudo. / The genus Acacia includes fast-growing short-rotation (7 to 9 years) forest tree species of commercial interest to produce pulp, wood panels, and energy. In Brazil, the utilization of species of the genus Acacia to produce short fiber pulp is still highly restricted and few studies are available that demonstrate the potential use of this raw material to obtain pulp presenting the properties displayed by species of the genus Eucalyptus. This study aimed at analyzing the potential of some species of the genus Acacia (A. aulacocarpa, A. auriculiformis, A. crassicarpa, A. mangium) planted in Brazil to produce kraft pulp, considering the aspects related to wood and pulp quality, consumption of chemical reagents during the pulping process, yield, and cellulose pulp production capacity. Furthermore, this work searched for strategical information for the national pulp and paper sector as to possible threats and opportunities presented by materials not used in Brazil in order to provide knowledge and discuss the potential competitiveness of these types of wood in the world market for pulp and paper. To accomplish these goals, we used 11 5-year-old distinct genetic materials, each one of them considered a different treatment. The following traits were evaluated: basic density, longitudinal variation, fiber dimensions, chemical composition, and kraft pulping process parameters (total yield, screened yield, rejects content, kappa number and relations). To carry out these evaluations, each wood species underwent the kraft pulping process considering six levels of active alkalis: 18.0, 19.5, 21.0, 22.5, 24.0, and 25.5%, keeping all other cooking variables constant. We observed that the model of longitudinal variation in the basic density maintains the trend of reaching higher values in the base of the tree and minimum values between 25% and 50% of the commercial height. The values found for the chemical composition were different for all the species studied and the holocellulose content ranged from a minimum of 60.99% found for A. auriculiformis (1) to a maximum of 68.79% found for A. aulacocarpa (1). The results obtained for fiber dimensions did not present defined patterns of variation among the species. The kraft pulping process parameters showed differences among Acacia species for the distinct levels of active alkalis. Considering the pulping process curve to get the kappa number of 18 among the species studied, the average alkali demand was 23.8% and the average depurated yield under these conditions was 54.72%. A. crassicarpa procedure 1 presented the highest conversion into wood mass (t/ha) to produce cellulose and A. mangium procedures (1, 2, 3, and mainly 4) reached the best results in terms of yield when they underwent the kraft pulping process compared to all the species studied herein.

O aumento do consumo da madeira e de seus produtos, como os painéis de madeira, estimula o desenvolvimento de tecnologia de produtos que utilizam os insumos caracterizados como resíduos. Neste aspecto, o país reúne vantagens competitivas, pela extensa área de plantações de eucalipto de alta produtividade, detém a primeira posição na produção de cana-de-açúcar e possui um parque industrial com avançada tecnologia de produção de painéis de fibras e de partículas. Com este contexto, o presente trabalho teve como principal objetivo a confecção e a caracterização tecnológica de painéis de fibras de madeira de eucalipto, Eucalyptus grandis e de partículas do bagaço do colmo de cana-de-açúcar, Saccharum sp. Os ensaios laboratoriais compreenderam, inicialmente, a caracterização macroscópica das matérias primas e suas misturas, bem como classificação granulométrica do bagaço de cana-de-açúcar. Em seguida, foram estabelecidas 2 etapas referentes ao processo de confecção dos painéis, denominadas etapa A (0-100% de bagaço de cana-de-açúcar, com variações de 25%; 14% de resina UF) e etapa B (0-25% de bagaço de cana-de-açúcar, com variações de 5%; 13 e 16% de resina UF). A caracterização tecnológica dos painéis compreendeu a análise da sua morfologia (microscopia MEV, microtomografia de raios X/microCT), densitometria de raios X, propriedades físicas (densidade, inchamento, absorção e umidade), mecânicas (MOR, MOE, resistências à trações perpendicular e superficial, arrancamento de parafuso); análises óticas por deflectometria, química (espectroscopia NIR, teor de formol livre e sílica) e durabilidade natural (bioensaios de fungos xilófagos e cupins). Os resultados da avaliação morfológica indicaram diferenças da estrutura anatômica das matérias primas e de granulometria das partículas de bagaço de cana-de-açúcar. A avaliação morfológica dos painéis evidenciou, através da microCT, a homogeneidade da matriz fibrosa, cuja composição anatômica foi diferenciada através do MEV. Na caracterização das propriedades físico-mecânicas, os perfis de densidade aparente dos painéis, típicos de painéis de fibras, indicaram a influência da matéria prima e sua mistura. Ainda, verificou-se uma redução das propriedades mecânicas, notadamente MOR, MOE e resistência á tração perpendicular, dos painéis confeccionados com mais de 50% de partículas do bagaço de cana-de-açúcar; quanto à resina, 16% resultou em melhor desempenho tecnológico em relação à 13%. Os valores de MOE dos painéis foram similares aos obtidos pela aplicação da técnica ótica de deflectometria. O aumento percentual de partículas do bagaço de cana-de-açúcar nos painéis resultou em redução do teor de formol livre e no aumento do teor de sílica. A aplicação da metodologia NIR permitiu a diferenciação das fibras da madeira de eucalipto e das partículas de bagaço de cana-de-açúcar e seus percentuais praticados. Nos bioensaios os painéis (etapa B) não apresentaram diferenças significativas quanto à resistência ao ataque de fungos e cupins. Os resultados permitem concluir que os painéis de fibras de eucalipto e partículas de bagaço de cana-de-açúcar, como matéria prima alternativa e em percentuais entre 5-25%, apresentaram propriedades tecnológicas que atendem às normas, indicando o potencial da utilização desta biomassa para produtos de maior valor agregado. / The increased consumption of wood and its products, such as wood panels, stimulates the development of technology for products that use inputs characterized as waste. In this respect, Brazil has competitive advantages regarding the large area of high-yield eucalyptus crops; Brazil is the worlds major sugarcane producer and has an industrial sector with advanced technology for fiberboards and particleboards production. Therefore, this study aimed to develop the manufacture and technological characterization of wood fibers from eucalyptus, Eucalyptus grandis, and stalk particles of sugarcane bagasse, Saccharum sp. Laboratory analyses included, initially, the macroscopic characterization of raw materials and their mixtures as well as sorting granules of crushed sugarcane bagasse. Then, two steps were established for the panel-making process, called phase A (0-100% of sugarcane bagasse, with variations of 25%, 14% UF resin) and phase B (0 - 25% of sugarcane bagasse, with variations of 5%, 13 and 16% UF resin). The technological characterization of the panels comprised the morphology analysis (SEM microscopy, X-ray microtomography / microCT), X-ray densitometry, physical properties (density, swelling in thickness, absorption and moisture content), mechanical (MOR, MOE, internal bond, surface resistance and axial withdrawal of screw); optical analysis by deflectometry, chemical (NIR spectroscopy, free formaldehyde content of sand content) and natural durability (bioassays of fungi and termites). The results indicated morphological differences of anatomical structure of raw materials and particle size of sugarcane bagasse. The morphological evaluation of the panels showed, through the microCT, the homogeneity of the fibrous matrix, whose anatomical composition was different through SEM. In the characterization of physical-mechanical properties, the density profiles of the panels, typical of fiberboards, indicated the influence of raw materials and their mixture. Still, there was a reduction of mechanical properties, notably MOR, MOE and internal bond to the panels made with more than 50% of sugarcane bagasse particles; regarding the resin, 16% resulted in better technological performance compared to 13%. The MOE values of the panels were similar to those obtained by applying the deflectometry technique. The percentage of sugarcane bagasse particles in the panels resulted in reduction of the level of free formaldehyde and increase of the sand content. The use of the NIR methodology allowed the differentiation of eucalyptus wood fibers and particles of sugarcane and their percentage applied. In bioassays, the panels (step B) showed no significant differences in resistance to fungi and termites. The results indicate that the panels of eucalyptus fibers and particles of sugarcane bagasse, as an alternative raw material and at percentages between 5-25% showed technological properties that meet the standards, indicating the potential use of this biomass for products with higher value added.

Specimens of 6 species of threatened, vulnerable, and endangered turtles (Cuora amboinensis, Cyclemys dentata, Heosemys grandis, Orlitia borneensis, Pyxidea mouhotii, and Siebenrockiella crassicollis) belonging to family Bataguridae, were confiscated in Hong Kong, China on 11 December 2001 by international authorities. Endohelminth studies on these turtle species are scarce, and this study provided a rare opportunity to examine a limited number of specimens for endohelminths. Ten different parasite species were collected and there were 16 new host records. This is the first record of a parasite from P. mouhotii. The parasite prevalences found in this study provide a basis for a better understanding of the phylogenetic relationships of the family Bataguridae to other families, especially Testudinidae. Based on known life cycles, parasites found provided an indication of food preferences of these 6 turtle species that support previous studies of the turtles' feeding habits. However, the results of the parasite survey from O. borneensis provided additional feeding habit information. The list of endohelminths herein is intended to provide a foundation for future parasite studies of the 6 species of Asian turtles.

Specimens of 6 species of threatened, vulnerable, and endangered turtles (Cuora amboinensis, Cyclemys dentata, Heosemys grandis, Orlitia borneensis, Pyxidea mouhotii, and Siebenrockiella crassicollis) belonging to family Bataguridae, were confiscated in Hong Kong, China on 11 December 2001 by international authorities. Endohelminth studies on these turtle species are scarce, and this study provided a rare opportunity to examine a limited number of specimens for endohelminths. Ten different parasite species were collected and there were 16 new host records. This is the first record of a parasite from P. mouhotii. The parasite prevalences found in this study provide a basis for a better understanding of the phylogenetic relationships of the family Bataguridae to other families, especially Testudinidae. Based on known life cycles, parasites found provided an indication of food preferences of these 6 turtle species that support previous studies of the turtles' feeding habits. However, the results of the parasite survey from O. borneensis provided additional feeding habit information. The list of endohelminths herein is intended to provide a foundation for future parasite studies of the 6 species of Asian turtles.

Thesis (MScFor)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: A field trial of six replications was established to test the effect of various wood ash and fertilisers application rates on soil chemistry, tree nutrition and early growth rate of a clonal Eucalyptus grandis x urophylla stand. Wood ash from pulpmills is currently disposed of in landfills. Increasing costs and potential environmental risks have driven companies to investigate alternative disposal methods. Ash consists of a combination of carbonates, hydroxides and other calcium containing minerals that induce the liming effect if ash is applied to a soil. The trial was established near Richards Bay in October 2013 on a sandy soil with a low buffer capacity and a pH of approximately 5.5. The trial consists of four wood ash application rates in combination with three levels of fertiliser, viz. no fertiliser, 150 g conventional NPK fertiliser mixture, or 320g NPK controlled release mixture. Fertiliser mixtures and application levels were based on previous fertiliser trials in the region. Ash application rates for the field trial were based on a lab incubation study done with soil samples from Richards Bay, to which increasing amounts of lime were added. The study tested wood ash application rates of 0, 300, 600 and 1200 kg/ha. Field measurements were taken at 4 and 8 months after trial establishment. The primary objective was to investigate which application levels in combination with the type of fertiliser could be applied to soils without negatively affecting the stand nutrition or increase the levels of potentially harmful elements in the soil; thus investigating the feasibility of safely disposing wood ash on plantation soils as an alternative disposal method. Soil nutrient concentrations were not affected by individual wood ash treatments, but more a product of the time interval after the ash additions were made. Soil C, P, K+ and Mg2+ showed decreased concentrations from 4-8 months after establishment. Ca2+ concentrations increased in the same time interval. In addition, Na+ and B concentrations decreased from 4-8 months. Soil heavy metal concentrations for Cd, Hg, Cr and Pb, analysed for 0-1200 kg/ha ash rates, were well below toxic levels at both time intervals. Wood ash induced a temporary liming effect. Mean soil pH increased with 0.6 units for the period 0 - 4 months and decreased with 0.4 units at 4 - 8 months after trial establishment. Foliar nutrient analyses and assessment techniques revealed sub-optimal nutrient concentrations for P, K and Zn at 4 and 8 months of age. Concentrations were defined as sub-optimal, as none of the nutrients were below critical levels. Foliar heavy metal concentrations for Cd, Hg, Cr and Pb, measured at both time intervals, were less than 1mg/kg. The small concentrations found in this project were attributed to the low bioavailability of all four elements and were likely a product of the edaphic factors at Richards Bay, which was representative of a large greater portion of the Zululand coastal plain sites. The response in biomass index ranged between 13 % and 683 % relative to the control treatment (A0F0). Results showed that application of purely wood ash, or in combination with a supplementary N and P source increased growth up to 8 months after trial establishment for wood ash applications up to 1200 kg/ha. This project demonstrated that 1200 kg/ha wood ash can safely be disposed of on a typical Zululand coastal sand with little environmental risk and no supressed growth, provided that it is balanced with an appropriate NP fertiliser. / AFRIKAANSE OPSOMMING: ‘n Veldproef met ses herhalings is in Oktober 2013 uitgelê met die doel om die uitwerking van verskillende vlakke hout as en kunsmis toedienings op die grond-voedingstof status, boom-voedingstof status en die groei-tempo van ‘n Eucalyptus grandis x urophylla hibried plantasie te bestudeer. Hout as by pulpmeulens word tans weggegooi op stortingsterreine. Toenemende onkostes vir storting en die omgewingsrisiko’s gebonde aan stortingsterreine, dryf maatskappye om verbeterde en meer omgewingsvriendelike metodes te ondersoek om van die as ontslae te raak. Hout as bestaan uit ‘n reeks karbonate, hidroksiede en kalsium bevattende minerale en is verantwoordelik vir die bekalkingseffek op die grond na toediening. Die veldproef is geleë naby Richardsbaai op ‘n sanderige grond met n lae bufferkapasiteit en pH van ongeveer 5.5. Die proef het vier hout as vlakke getoets, gekombineer met drie vlakke van bemesting: geen, 150g konvensionele landbou kunsmis (CV) óf 320g beheerd-vrystellende kunmis (CRF). Die kunsmismengsels en vlakke van bemesting is gebaseer op bestaande of voltooide bemestingseksperimente in die streek. Hout as vlakke was bereken in gekontroleerde laboratorium toestande en gebaseer op ‘n inkubasie studie met grond monsters verkry vanaf Richardsbaai, waarby toenemende vlakke suiwer landboukalk gevoeg is. Die veldproef het hout as vlakke van 0, 300, 600 en 1200 kg/ha getoets. Veld metings is op 4 en 8 maande na behandeling geneem. Die primêre doelwit van die studie was om te bepaal watter vlak hout as en kunmis kombinasie toegedien kan word, sonder om die grond-voedingstof status negatief te beïnvloed of ‘n potensiële skadelike uitwerking op die plantasie groei te veroorsaak. Die uiteinde van die studie was om die haalbaarheid van hout as toedienings op plantasie gronde te bestudeer relatief tot die huidige praktyk van storting, insluitend die risiko van moontlike skadelike newe-effekte. Grondvoedingstatus was nie beduidend beïnvloed deur individuele hout as toevoegings nie, maar was eerder ‘n funksie van die tydsduur sedert behandeling. Grond koolstof, P anione, K+ en Mg2+ konsentrasies het beduidend afgeneem in die periode van 4 - 8 maande na behandling. Die Ca2+ konsentrasies het toegeneem tussen 4 en 8 maande en terselfdertyd het Na+ en B konsentrasies afgeneem. Die swaarmetaal status, spesifiek vir Cd, Hg, Cr en Pb, vir toevoegings van 0-1200 kg/ha hout as was beduidend laer as toelaatbare vlakke in gronde op albei tydsintervalle. Die hout as het ‘n tydelike toename in grond pH veroorsaak. Die gemiddelde pH het tussen 0 - 4 maande toegeneem met 0.6 eenhede en gedurende 4 - 8 maande afgeem met 0.4 eenhede. Blaarontledings en voedingstof assesseringsmetodes het sub-optimale konsentrasies vir P, K en Zn getoon op die ouderdom van 4 en 8 maande. Voedingstof konsentrasies is as sub-optimaal geklassifiseer, omdat konsentrasies nooit laer as kritieke waardes vir gebreksimptome was nie. Die inhoud van Cd, Hg, Cr en Pb in blare was aansienlik kleiner as 1 mg/kg op albei tydsintervalle. Die merkwaardige lae konsentrasies wat in die projek aangeteken is, word toegekryf aan die lae bio-beskikbaarheid van al vier elemente as gevolg van die edafiese faktore eie aan die Richardsbaai omgewing (en ook aan groot dele van die Zoeloelandse kusvlakte). Die groeireaksie (bepaal as biomassa indeks op ouderdom 8 maande) het gewissel van 13 % - 683 % groter as die kontrole behandeling (A0F0). Resultate het bewys dat toedienings van suiwer hout as, of hout as gekombineer met ‘n addisionele N en P kunsmisbron die groei postief beïnvloed tot op die ouderdom van 8 maande. Die studie het bewys dat 1200 kg/ha hout as veilig toegedien kan word op die sandgronde van die kusgebiede in Zululand, met minimale omgewingsrisiko en geen tekens onderdrukte groei nie, mits dit gebalanseer word met ‘n geskikte NP kunsmisbron.

Rhizophagus grandis is one of the rare examples of totally specific predators: it only preys upon the bark beetle Dendroctonus micans in its native range (Europe and Asia). In the course of coevolution in such predator-prey systems, prey are selected for avoidance and resistance mechanisms against predators. Previous laboratory trials suggested that R. grandis could lay more eggs in presence of exotic prey species with an ecology similar to that of D. micans, but which could not evolve resistances against this predator, such as the North American parasitic bark beetles D. punctatus and D. valens. The specificity of the association R. grandis-D. micans is thought to depend on chemical signals (kairomones) used by the predator to find a gallery of its prey and to adjust its oviposition to the number of prey larvae available inside. However, the exact nature of the chemical signals regulating R. grandis’ oviposition is still unknown. While these signals seem specific in nature, stimulation of the predator’s oviposition by exotic prey species suggests that specificity may be constrained by geography. Unlike most bark beetles, which kill living trees or feed on dying trees, D. micans completes its development on healthy trees as a true parasite. This niche is highly defended by tree toxicants (terpenes among others) to which both D. micans and R. grandis are resistant. Insects possess their own detoxification processes, but they may also rely on symbiotic microorganisms (bacteria and fungi) to contend with the specific constraints of their niche. In comparison to other bark beetles, microbial communities of parasitic bark beetles are yet poorly known, as in the case of D. micans and D. punctatus. Apart from detoxification, insect symbionts may provide nutritional supplementation, protection against pathogens, or components of the chemical communication, which affect the hosts as well as partners of the tritrophic relationship tree-bark beetle-natural enemies. The system R. grandis-D. micans is a unique opportunity to study several aspects of this coevolution which are poorly understood to date. The objectives of this thesis were:- (1) the comparison of the oviposition performances of R. grandis on the specific prey D. micans, and on the exotic prey D. punctatus and D. valens, in order to emphasize possible prey resistance mechanisms; - (2) the identification of the chemical signals regulating R. grandis’ oviposition, and the evaluation of their role in the specificity of the association with D. micans, in presence of the exotic prey D. punctatus and D. valens; - (3) the characterization of the bacterial and fungal communities associated with non-aggressive populations of the bark beetles D. micans, D. punctatus and D. valens, and investigating how these microbial symbionts may affect bark beetle hosts in respect of their ecology as well as the tritrophic relationship tree-bark beetle-natural enemies. Our results show that R. grandis laid equivalent numbers of eggs with the native prey D. micans and with the exotic prey D. punctatus and D. valens, which could illustrate that R. grandis’ specificity is constrained by geography but which does not emphasize possible prey resistance mechanisms against the long-standing predator. We identified robust candidates to the stimulation and inhibition of R. grandis’ oviposition which should be confirmed in bioassays. Finally, we report that the bacterial and fungal communities of non-aggressive populations of D. micans, D. punctatus and D. valens are mainly composed of widespread environmental Enterobacteria and yeasts, and we discuss the various ways they may influence bark beetle hosts in respect of their life histories including the attacked trees and their natural enemies. Overall, this thesis illustrates the need to encompass all levels of complexity, from prey symbionts and semiochemicals to predators, to study systems like R. grandis-D. micans. / Rhizophagus grandis est un des rares exemples de prédateurs totalement spécifiques :présent en Europe et en Asie, il se nourrit exclusivement du scolyte Dendroctonus micans. Dans de telles associations, la coévolution prédateur-proie mène à la sélection de mécanismes d’évitement ou de résistance chez la proie, contre le prédateur. De précédentes observations en laboratoire ont suggéré que R. grandis pouvait pondre davantage d’œufs en présence de proies exotiques d’écologie comparable à celle de D. micans, mais qui n’auraient pu développer de résistance à l’encontre de ce prédateur, à l’instar des scolytes parasitiques nord-américains D. punctatus et D. valens. Il semble que la spécificité de l’association R. grandis-D. micans repose sur des signaux chimiques (kairomones) qui permettent au prédateur de repérer les galeries de sa proie et d’y ajuster le nombre d’œufs déposé à la quantité de larves de proies disponible. Néanmoins, on ignore encore la nature exacte des signaux régulant l’oviposition de R. grandis. Le fait que l’oviposition soit stimulée par des proies exotiques indique que la spécificité de cette association pourrait être limitée par des barrières géographiques. Contrairement à la plupart des scolytes qui tue des arbres ou s’attaque à des arbres mourants, D. micans se développe intégralement sur des arbres en bonne santé, en véritable parasite. Cette niche est fortement défendue par les composés toxiques de l’arbre (en particulier les terpènes), auxquels à la fois D. micans et R. grandis sont résistants. Certains insectes possèdent leurs propres processus de détoxification, mais ils peuvent également bénéficier de l’aide de microorganismes symbiotiques (bactéries et champignons). En comparaison avec les autres scolytes, les communautés microbiennes associées aux scolytes parasitiques est très peu documentée, comme dans le cas de D. micans et D. punctatus. En dehors de la détoxification, les symbiotes d’insectes peuvent contribuer à leur nutrition, les protéger contre des pathogènes, ou intervenir dans la communication chimique, ce qui affecte leurs hôtes comme les autres acteurs de la relation tritrophique arbre-scolyte-ennemi naturel. L’association R. grandis-D. micans est une opportunité unique d’étudier des aspects méconnus de la coévolution. Les objectifs de cette thèse étaient de :- (1) comparer le nombre d’œufs pondu par R. grandis sur sa proie spécifique, D. micans, et sur les proies exotiques D. punctatus et D. valens, afin de mettre en évidence de possibles résistances ;- (2) identifier les signaux chimiques qui régulent l’oviposition de R. grandis, et évaluer leur rôle dans la spécificité de l’association avec D. micans, en présence des proies exotiques D. punctatus et D. valens ;- (3) caractériser les communautés bactérienne et fongique associées aux populations parasitiques des scolytes D. micans, D. punctatus et D. valens, et investiguer comment ces microorganismes symbiotiques peuvent influencer leurs hôtes, selon leurs contraintes écologiques, ainsi que leurs ennemis naturels et arbres-hôtes. Nos résultats révèlent une oviposition équivalente de R. grandis en présence de la proie native D. micans et des proies exotiques D. punctatus et D. valens, ce qui illustre que la spécificité de cette association pourrait être limitée par des barrières géographiques mais ne met pas en évidence de possibles résistances à l’encontre du prédateur de longue date. Nous avons identifié des candidats robustes à la stimulation et à l’inhibition de la ponte de R. grandis, et leur rôle devrait être confirmé par des bioessais. Enfin, nous rapportons que la communauté microbienne associée aux populations parasitiques des scolytes D. micans, D. punctatus et D. valens est principalement constituée d’Entérobactéries et de levures répandues, et nous discutons des différentes façons dont ces symbiotes peuvent affecter leurs hôtes et autres acteurs de la relation tritrophique arbre-scolyte-ennemi naturel, selon leurs écologies respectives. Dans son ensemble, cette thèse souligne l’importance de considérer tous les niveaux de complexité biologique, des microorganismes associés aux proies jusqu’aux prédateurs, afin d’étudier des systèmes comme R. grandis-D. micans. / Doctorat en Sciences / info:eu-repo/semantics/nonPublished

O aumento do consumo da madeira e de seus produtos, como os painéis de madeira, estimula o desenvolvimento de tecnologia de produtos que utilizam os insumos caracterizados como resíduos. Neste aspecto, o país reúne vantagens competitivas, pela extensa área de plantações de eucalipto de alta produtividade, detém a primeira posição na produção de cana-de-açúcar e possui um parque industrial com avançada tecnologia de produção de painéis de fibras e de partículas. Com este contexto, o presente trabalho teve como principal objetivo a confecção e a caracterização tecnológica de painéis de fibras de madeira de eucalipto, Eucalyptus grandis e de partículas do bagaço do colmo de cana-de-açúcar, Saccharum sp. Os ensaios laboratoriais compreenderam, inicialmente, a caracterização macroscópica das matérias primas e suas misturas, bem como classificação granulométrica do bagaço de cana-de-açúcar. Em seguida, foram estabelecidas 2 etapas referentes ao processo de confecção dos painéis, denominadas etapa A (0-100% de bagaço de cana-de-açúcar, com variações de 25%; 14% de resina UF) e etapa B (0-25% de bagaço de cana-de-açúcar, com variações de 5%; 13 e 16% de resina UF). A caracterização tecnológica dos painéis compreendeu a análise da sua morfologia (microscopia MEV, microtomografia de raios X/microCT), densitometria de raios X, propriedades físicas (densidade, inchamento, absorção e umidade), mecânicas (MOR, MOE, resistências à trações perpendicular e superficial, arrancamento de parafuso); análises óticas por deflectometria, química (espectroscopia NIR, teor de formol livre e sílica) e durabilidade natural (bioensaios de fungos xilófagos e cupins). Os resultados da avaliação morfológica indicaram diferenças da estrutura anatômica das matérias primas e de granulometria das partículas de bagaço de cana-de-açúcar. A avaliação morfológica dos painéis evidenciou, através da microCT, a homogeneidade da matriz fibrosa, cuja composição anatômica foi diferenciada através do MEV. Na caracterização das propriedades físico-mecânicas, os perfis de densidade aparente dos painéis, típicos de painéis de fibras, indicaram a influência da matéria prima e sua mistura. Ainda, verificou-se uma redução das propriedades mecânicas, notadamente MOR, MOE e resistência á tração perpendicular, dos painéis confeccionados com mais de 50% de partículas do bagaço de cana-de-açúcar; quanto à resina, 16% resultou em melhor desempenho tecnológico em relação à 13%. Os valores de MOE dos painéis foram similares aos obtidos pela aplicação da técnica ótica de deflectometria. O aumento percentual de partículas do bagaço de cana-de-açúcar nos painéis resultou em redução do teor de formol livre e no aumento do teor de sílica. A aplicação da metodologia NIR permitiu a diferenciação das fibras da madeira de eucalipto e das partículas de bagaço de cana-de-açúcar e seus percentuais praticados. Nos bioensaios os painéis (etapa B) não apresentaram diferenças significativas quanto à resistência ao ataque de fungos e cupins. Os resultados permitem concluir que os painéis de fibras de eucalipto e partículas de bagaço de cana-de-açúcar, como matéria prima alternativa e em percentuais entre 5-25%, apresentaram propriedades tecnológicas que atendem às normas, indicando o potencial da utilização desta biomassa para produtos de maior valor agregado. / The increased consumption of wood and its products, such as wood panels, stimulates the development of technology for products that use inputs characterized as waste. In this respect, Brazil has competitive advantages regarding the large area of high-yield eucalyptus crops; Brazil is the worlds major sugarcane producer and has an industrial sector with advanced technology for fiberboards and particleboards production. Therefore, this study aimed to develop the manufacture and technological characterization of wood fibers from eucalyptus, Eucalyptus grandis, and stalk particles of sugarcane bagasse, Saccharum sp. Laboratory analyses included, initially, the macroscopic characterization of raw materials and their mixtures as well as sorting granules of crushed sugarcane bagasse. Then, two steps were established for the panel-making process, called phase A (0-100% of sugarcane bagasse, with variations of 25%, 14% UF resin) and phase B (0 - 25% of sugarcane bagasse, with variations of 5%, 13 and 16% UF resin). The technological characterization of the panels comprised the morphology analysis (SEM microscopy, X-ray microtomography / microCT), X-ray densitometry, physical properties (density, swelling in thickness, absorption and moisture content), mechanical (MOR, MOE, internal bond, surface resistance and axial withdrawal of screw); optical analysis by deflectometry, chemical (NIR spectroscopy, free formaldehyde content of sand content) and natural durability (bioassays of fungi and termites). The results indicated morphological differences of anatomical structure of raw materials and particle size of sugarcane bagasse. The morphological evaluation of the panels showed, through the microCT, the homogeneity of the fibrous matrix, whose anatomical composition was different through SEM. In the characterization of physical-mechanical properties, the density profiles of the panels, typical of fiberboards, indicated the influence of raw materials and their mixture. Still, there was a reduction of mechanical properties, notably MOR, MOE and internal bond to the panels made with more than 50% of sugarcane bagasse particles; regarding the resin, 16% resulted in better technological performance compared to 13%. The MOE values of the panels were similar to those obtained by applying the deflectometry technique. The percentage of sugarcane bagasse particles in the panels resulted in reduction of the level of free formaldehyde and increase of the sand content. The use of the NIR methodology allowed the differentiation of eucalyptus wood fibers and particles of sugarcane and their percentage applied. In bioassays, the panels (step B) showed no significant differences in resistance to fungi and termites. The results indicate that the panels of eucalyptus fibers and particles of sugarcane bagasse, as an alternative raw material and at percentages between 5-25% showed technological properties that meet the standards, indicating the potential use of this biomass for products with higher value added.

<div>Following the 2010 Deepwater Horizon oil spill, extensive research has been conducted on the toxicity of oil and polycyclic aromatic hydrocarbons (PAHs) in the aquatic environment. The location and timing of the Deepwater Horizon surface slick coincided with the spawning seasons of many important pelagic and estuarine fish species. As such, there has been particular emphasis placed on the effects of PAHs on sensitive life history stages in fish, such as the embryonic and larval periods. Additionally, the spill occurred throughout the spring and summer months which, in estuaries, are marked by regular fluctuations in abiotic environmental factors such as dissolved oxygen, salinity, and temperature. Until recently, there has been little work done to elucidate the combined effects that PAHs from oil spills and adverse environmental conditions (hypoxia, increased salinity, and elevated temperatures).</div><div>Work presented in this dissertation uses next generation sequencing technology (RNA Seq) to determine differential gene expression in larval estuarine teleosts following exposure to adverse environmental conditions and PAHs. Downstream canonical pathway and toxicological function analysis were then applied to the identified differentially expressed genes (DEGs) to predict cardiotoxic responses at the organismal level. To verify the predicted responses, a phenotypic anchoring study was conducted and identified a cardiotoxic phenotype (pericardial edema) and reduced cardiac output in embryos exposed to oil. Finally, the mechano-genetic interplay governing the morphological development of the teleost heart was investigated and correlations between developmental gene expression and blood flow forces within the cardiovascular system were identified.</div>