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1

Kraemer, Ute. "Nickel hyperaccumulation in the genus Alyssum L." Thesis, University of Oxford, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318487.

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2

Flynn, Thomas Alexander. "Evolution of nickel hyperaccumulation in Alyssum L." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:fec1aee2-897b-4da0-b756-86385a802077.

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Phylogenetic studies are providing powerful new insights into the evolution of complex traits. Metal hyperaccumulation is an unusual and complex physiological trait found in about 500 plant species and is associated with an exceptionally high degree of tolerance of metalliferous soils. Alyssum L. (Brassicaceae) is the largest known hyperaccumulator genus, comprising approximately 188 species distributed throughout the Mediterranean region and south-west Asia. Approximately one-quarter of these are largely restricted to areas of serpentine soils and have the ability to accumulate nickel to high concentrations in shoot tissue. This genus provides a good example in which to study the origins of a complex physiological trait, but its phylogeny is currently poorly understood. To produce a well-resolved phylogenetic tree to investigate the number and timing of origins of nickel hyperaccumulation within Alyssum, DNA sequences were generated for four chloroplast regions (matK, rps16–trnK, trnD–T and trnL–F) from 170 of 255 species in the tribe Alysseae. Additional sequencing was carried out for the chloroplast genes ndhF and rbcL and the nuclear gene PHYA. A Bayesian analysis employing a relaxed uncorrelated lognormal molecular clock and multiple fossil-age calibration points was carried out to reconstruct a time-calibrated phylogeny of this tribe using appropriate outgroups. Optimization of the nickel hyperaccumulation trait onto the resulting phylogenetic tree suggests that nickel hyperaccumulation arose twice in the Alysseae in the late Miocene/early Pliocene: 3.3–8.3 Mya in Alyssum and 6.3–8.8 Mya in Bornmuellera. The single origin in Alyssum is strongly associated with a significant acceleration in net species diversification rate, suggesting the ability to hyperaccumulate nickel could have provided a key evolutionary innovation facilitating rapid range expansion and subsequent species diversification. The scattered distribution of nickel hyperaccumulators across small island-like patches of serpentine soil suggests that allopatric speciation may have driven rapid diversification in this clade.
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3

Mugford, Sam. "The molecular basis of nickel hyperaccumulation in Alyssum L." Thesis, University of Oxford, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.670183.

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4

Shallari, Seit. "Biodisponibilité du nickel du sol pour l'hyperaccumulateur Alyssum murale." Vandoeuvre-les-Nancy, INPL, 1997. http://www.theses.fr/1997INPL112N.

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Les plantes hyperaccumulatrices pourraient constituer une alternative ou un complément aux méthodes physico-chimiques pour le traitement des sols pollués par les métaux. L’efficacité de cette phytoextraction repose en grande partie sur la biodisponibilité des métaux présents dans les sols. La thèse était destinée à comprendre les processus de fourniture des métaux du sol aux hyperaccumulateurs. Dans ce but, une prospection de terrain a d'abord été effectuée en Albanie pour déterminer la flore métallicole présente sur des sites de serpentines présentant des teneurs élevées en Cd, Co, Cr et Ni et sur d'anciens sites industriels pollués par Cd, Cu, Pb et Zn. Puis, ayant focalisé sur l'hyperaccumulateur de Ni Alyssum murale, des cultures en vases de végétation ont été conduites afin de tester l'influence de la fertilisation phosphatée sur la biodisponibilité du Ni. Enfin, le Ni assimilable du sol par A. Murale a été caractérisé à l'aide des méthodes isotopiques, i. E. Cinétiques de dilution isotopique et marquage avec culture en vases de végétation, et les compositions isotopiques du Ni dans la solution du sol et dans la plante hyperaccumulatrice ont été comparées. Les résultats montrent que co-existent de nombreuses espèces végétales sur les sites métallifères et confirment l'abondance sur les sites de serpentine et sites industriels d'espèces du genre Alyssum ayant la propriété d'hyperaccumuler le Ni à des concentrations supérieures à 1% dans la matière sèche. La fertilité phosphorique n'est pas apparue comme un facteur limitant la croissance de A. Murale mais a occasionné une légère augmentation du prélèvement du Ni par la plante. La comparaison des compositions isotopiques du Ni dans la solution du sol et dans la plante a permis de démontrer que l'hyperaccumulateur prélève son Ni dans le pool des ions isotopiquement échangeables, c'est à dire dans le même pool que les plantes non hyperaccumulatrices. Le métal biodisponible parait ainsi être représenté par un seul compartiment dans lequel l'ensemble des plantes puisent en fonction de leur capacité de prélèvement. Après une culture de plantes hyperaccumulatrices, ce compartiment est fortement diminué.
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5

Stopps, Gregory James. "Biology of the rangeland weed hoary alyssum (Berteroa incana (L.) DC.)." Thesis, University of British Columbia, 2012. http://hdl.handle.net/2429/42131.

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Hoary alyssum (Berteroa incana (L.) DC) has become a serious weed of rangelands, pastures, and forage crops in British Columbia. In order to develop effective management strategies for this weed, a sound knowledge of its biology and ecology is essential. The goal of this research is to improve our understanding of the biology of hoary alyssum and to identify vulnerable links in its persistence strategy that may be exploited to develop effective management strategies for this weed. The distribution of hoary alyssum seeds in the soil profile; the size and persistence of its seed bank; the effect of burial depth on the dynamics of seed dormancy and germination; the response to mechanical removal of flowering shoots (mowing); the potential allelopathic influence on seed germination and seedling growth of associated forage grasses; and the effect of nitrogen fertilization on the growth of hoary alyssum and associated forage grasses were investigated. Results show: (1) 93-95% of hoary alyssum seeds were present in the top 4 cm of the soil profile at infested sites in the Morrissey Creek, BC area; (2) the size of soil seed banks ranged between 0 to 132.4 million seeds ha₋¹; (3) seeds on the soil surface showed little primary dormancy, but buried seeds showed some enforced and some induced dormancy; (4) mowing of flowering shoots resulted in the release of apical dominance and the regeneration of shoots; (5) delaying mowing until later stages of flower and seed development increased plant mortality, but some plants were still able to reproduce shoots and seed; (6) leachates of hoary alyssum leaves strongly inhibited the seed germination and seedling growth of grassy species in Petri dish assays, but this allelopathic influence was not observed consistently in soil assays; (7) hoary alyssum biomass increased in response to nitrogen (urea) fertilization, but forage grasses showed no response due to leaching of this nutrient; and (8) nitrogen fertilization promoted bolting and flowering in hoary alyssum. These results improve our understanding of hoary alyssum biology, and may aid in the development of effective management strategies for this weed.
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6

Saad, Ramez. "Agromine associant plantes hyperaccumulatrice de nickel et légumineuse, comme service écosystémique des sols ultramafiques." Thesis, Université de Lorraine, 2017. http://www.theses.fr/2017LORR0155/document.

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L’application de l’agromine à des zones ultramafiques délaissées constitue un enjeu majeur à la vue des surfaces potentiellement valorisables. Par contre, les sols ultramafiques sont particuliers avec de fortes concentrations en métaux et une quasi absence de matière organique. Malgré tout, la mise en place de l’agromine a déjà donné de bons résultats, couplée avec l’application d’herbicides et une fertilisation minérale. Notre défi a été de développer une agromine durable par la mise en place d’agro-écosystèmes basés sur l’introduction d’une légumineuse en association avec une plante hyperaccumulatrice et la suppression de tout intrant chimique. Nos résultats ont confirmé clairement que l'introduction d'une légumineuse dans l’agromine a amélioré la production de biomasse de Alyssum murale et les rendements de nickel par rapport à sa monoculture fertilisée et non fertilisée. Nos travaux ont également montré que l'insertion d'une légumineuse dans l’agromine permet d’améliorer la structure du sol avec des agrégats plus stables. De plus, de meilleures teneurs en carbone, azote et en matière organique ont été détectées. L’ensemble de ces éléments conduit ainsi à une amélioration globale de la structure du sol, de sa fertilité et de son biofonctionnement. Corrélativement, nos résultats ont mis en évidence les effets positifs de ces nouvelles pratiques, à la fois sur la taille, la diversité et les acitivités liées aux cycles biogéochimiques des communautés bactériennes. D’un point de vue écononique, l’introduction de la légumineuse dans l’agromine implique un gain financier et de temps du fait de la réduction de l'application d’engrais et de produits phytosanitaires. Enfin, tous ces avantages conduisent à une réhabilitation des sols ultramafiques avec une restauration de leurs qualités physique, chimique et biologique, tout en permettant à ces sols particuliers d’offrir plusieurs services écosystémiques
The application of agromining to abandoned ultramafic areas is a major challenge in the presence of potentially recoverable areas. Howerver, ultramafic soils are particular in terms of their fertility with high concentrations of metals and a near absence of organic matter. Nevertheless, this challenge was partly met by the application of chemical fertilizers and herbicides. Our challenge, through this PhD, was to develop a sustainable agro-ecosystem based on the introduction of a legume in association with the hyperaccumulating plant and then the reduction of any chemical input. Our results clearly confirmed that the introduction of a legume into these new cropping systems improved both the biomass production of Alyssum murale and the Ni yields in comparison to the fertilized and non-fertilized monoculture. Our work has also shown that the insertion of a legume into agromining cropping systems improves the structure of the soil due to stable and larger aggregates. In addition, higher levels of carbon and nitrogen and higher concentrations of organic matter were detected. These results led to an overall improvement of the soil structure, its fertility and its biofunctioning. Our results showed positive effects of these new cropping systems, both on the size of the bacterial communities and on the microbial enzymes involved in the soil biogeochemical cycles. In addition, the structure and diversity of bacterial communities were modified with the insertion of the legume, compared to the monoculture. Economically, the introduction of legume into cropping systems dedicated to Ni agromining involves a gain of money and time due to reduced application of mineral fertilizers as well as products of phytosanitary. Finally, all these benefits lead to the rehabilitation of ultramafic soils with the restoration of their physical, chemical and biological qualities while allowing these particular soils to offer many ecosystem services
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7

Barbaroux, Romain. "Développement d'un procédé hydrométallurgique de récupération du nickel." Thesis, Vandoeuvre-les-Nancy, INPL, 2010. http://www.theses.fr/2010INPL087N/document.

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Cette recherche s’inscrit dans le contexte de la conception d’une filière originale comprenant la phytoextraction du nickel par la plante hyperaccumulatrice Alyssum murale, endémique des sols de serpentine d’Albanie et de sa valorisation de ce nickel, l’objectif étant d’arriver à un produit à haute valeur ajoutée. Les sols de serpentine peuvent être considérés comme une ressource secondaire. Ils contiennent des concentrations élevées en nickel mais à des teneurs insuffisantes pour être exploités par l’industrie minière. La plante Alyssum murale peut extraire et concentrer le nickel dans ses tissus. Le nickel présent dans la biomasse a pu être solubilisé quasiment totalement à l’acide sulfurique, en réacteur fermé puis à contre-courant en trois étapes. Cette lixiviation a produit une solution contenant du nickel lié à des molécules organiques ainsi que d’autres métaux et composés organiques. Les procédés de raffinage directs comme la précipitation sélective ou l’électroplaquage n’ont pas permis d’isoler le nickel. Deux voies ont été explorées : (i) l’extraction par un solvant organique sélectif du nickel (Cyanex 272) suivie d’une contre extraction par une solution aqueuse et électrodéposition et (ii) la cristallisation d’un sel double à partir du lixiviat préparé après incinération de la biomasse. La première voie a permis d’obtenir le nickel métal sous forme de cathode, la seconde a conduit au sel double sulfate de nickel et d’ammonium. Les produits ont été caractérisés par différentes techniques. Une étude technico-économique a montré le fort potentiel économique de la production de sel double
This research has been done in the context of the design of an original method aiming at obtaining high added value products of nickel, combining phytoextraction and valorization. Phytoextraction is conducted with the hyperaccumulating plant Alyssum murale, endemic species of serpentine soils in Albania. Serpentine soils can be considered as secondary resources: they contain high concentrations of nickel, which are not high enough for conventional mining techniques. The plant Alyssum murale can extract and concentrate nickel in its tissues. Nickel present in the biomass could be almost totally solubilized in batch reactor and with a 3 step countercurrent process. This leaching produced a solution containing nickel bound to organic molecules and other metals and organic compounds as well. Direct separation processes (e.g. selective precipitation and electrowinning) did not enable us to obtain nickel. Two methods have been investigated: (i) extraction by an organic nickel –selective solvent (Cyanex 272), extraction by an aqueous solution and electrowinning and (ii) crystallization of a double salt, nickel ammonium sulfate, from a leaching solution obtained from biomass ashes. Nickel products were characterized by different techniques. A technico-economical study showed the high commercial potential of the double salt production
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8

Zhang, Xin. "Procédé hydrométallurgique pour la valorisation du nickel contenu dans les plantes hyperaccumulatrices." Thesis, Université de Lorraine, 2014. http://www.theses.fr/2014LORR0172/document.

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Certaines plantes, dites hyperaccumulatrices, ont la capacité de se développer sur des sols riches en métaux et d’accumuler ces métaux à des concentrations élevées. L’incinération de la biomasse produit des cendres qui contiennent de 10 à 25% en masse de Ni. Ce travail s’inscrit dans la continuité d’une recherche menée par l’équipe depuis plusieurs années, qui a donné lieu notamment à un brevet sur la production du sel double sulfate de nickel et d’ammonium hexahydraté (ANSH) à partir de la biomasse d’Alyssum murale. Le manuscrit comprend d’abord une synthèse bibliographique sur la phytomine, allant des hyperaccumulateurs aux procédés de valorisation, essentiellement centrée sur le nickel. Ensuite, ont été comparées quinze plantes hyperaccumulatrices (des genres Alyssum, Leptoplax et Bornmuellera) provenant d’Albanie ou de Grèce, en vue de leur application pour la phytomine. Les teneurs en nickel ont été mesurées dans les différents organes des plantes et dans les cendres obtenues par combustion. Les trois genres ont de l’intérêt pour l’application, les plantes contiennent 1 à 3% en masse de nickel et les cendres 15 à 20 %. Le procédé hydrométallurgique de production d’ANSH a été étudié étape par étape en vue d’optimiser chaque étape pour produire un sel très pur tout en économisant matière et énergie et minimisant la production d’effluents et de déchets. Ce travail a conduit à l’amélioration du procédé de départ. Enfin, de nouvelles pistes ont été proposées pour conduire à de nouveaux procédés et produits du nickel. Les résultats obtenus et la dynamique actuelle autour de la phytomine montrent l’intérêt de cette approche et annoncent son développement imminent
Some plants, known as hyperaccumulators, are able to develop on metal containing soils and to accumulate these metals at high concentrations in shoots. Biomass incineration leads to ash containing 10 to 25 wt % nickels, greater than in some mineral ores. This work follows a research that has been carried out by the team for several years, which has resulted in a patent on the hydrometallurgical production of the double salt ammonium and nickel hexahydrate (ANSH) from the biomass of Alyssum murale. It aims at improving the synthesis method of this salt in order to upscale it at the pilot scale and explore new methods leading to new products. The manuscript begins with a bibliographic review on phytomining from hyperaccumulators to metal recycling processes, essentially focused on nickel. Then ca 15 hyperaccumulator plants (genus Alyssum, Leptoplax and Bornmuellera) collected in Greece or Albania have been compared, in the objective of phytomining. Nickel concentrations were measured in the plant organs and in the ashes after combustion. The three types of plants are of great interest for the technology, they contain 1 to 3 wt % of nickel and the ashes 15 to 20%. The hydrometallurgical process of ANSH production was investigated step by step to optimize each step to produce a salt of high purity, to decrease materials and energy consumption and to minimize effluent and waste production. The process was thus improved. Eventually, new ideas have been tested for new processes and nickel products. The obtained results and the current dynamics prove the interest of phytomining and announce its imminent development
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9

Bettarini, Isabella. "The nickel hyperaccumulating plants of genus Odontarrhena (Brassicaceae): novel insights from molecular, physiological and biochemical analyses." Doctoral thesis, Università di Siena, 2021. http://hdl.handle.net/11365/1128453.

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Due to the high nickel concentrations, serpentine soils provide a very restrictive and selective environment for plant life. Some plants, termed “Ni-hyperaccumulators”, are adapted to live on these heavy-metal-enriched soils without toxicity symptoms. Ni-hyperaccumulators are increasingly important for research on metal tolerance, homeostasis and biotechnological applications. This project aims to investigate nickel accumulation in taxa and populations of Odontarrhena, a genus of tribe Alysseae (Brassicaceae) that includes over 85 species many of which are Ni-hyperaccumulators. Based on a previous systematic study conducted on poorly-known populations of Odontarrhena native to Albania we performed a molecular study to characterize taxa and populations of this genus. To this purpose we used DNA sequencing and the AFLP-fingerprint technique to reconstruct the species phylogenetic relationships and the population differentiation patterns in relation to their distribution, ploidy level, intensity of anthropic site disturbance, altitude, soil type and metal concentration population (Ni, Cr, Co, Ca, Mg). We found significant population differentiation, dominance of within-population variation, no isolation by geographic distance and existence of six genetic groups variously represented across the six taxa possibly due to hybridization especially in disturbed sites. Next, we compared metal concentrations in native Odontarrhena populations from Albania in relation to their soil of origin. We determined the concentration of the most important trace metals (Ni, Co, Cr, Mg, Ca, K, Fe and Mn) in soil, plant roots and shoots of five taxa from 20 different outcrops. We found large differences in mineral element concentrations in soils and also between the plants; shoot Ni concentrations in Albanian Odontarrhena taxa depend on soil Ni concentrations but not on species identity. For O. chalcidica, the most widely distributed species, this “environmental fingerprint” was found not only for Ni, but also for Ca and Mg. After these investigations on native populations from the natural environment, we designed an experimental study in controlled conditions. Plant seedlings of seven taxa and 11 populations of Odontarrhena from serpentine and non-serpentine sites of the Balkan peninsula and Italy were cultivated in hydroponics with increasing NiSO4 concentrations to determine plant growth and Ni accumulation. These plantlets were analyzed to test inter- and intra-specific differences in nickel tolerance and accumulation, in relation to Ni levels in the soils and in wild plants. We found a metal stimulatory effect on growth that was present in the low-dose zone and significantly fitted the Brain-Cousens hormetic model. Taxa showed broad variation in tolerance, with the most tolerant plants requiring the highest Ni concentration for optimal growth. Our data suggested that tolerance is associated with hyperaccumulation ability. Among the obligate and facultative serpentinophytic species of Odontarrhena that have been investigated we found a notable exception, O. sibirica, a facultative serpentinophyte in which accumulation ability was enigmatic from previous studies. We addressed this issue using observational and experimental methods as in our previous researches. We found that Ni-concentrations in the native populations sampled on serpentine soils in Greece were always much lower than the hyperaccumulation threshold. When cultivated together with other Ni-accumulating Odontarrhena species on the same natural ultramafic soil, O. sibirica was the only one unable to accumulate the metal. When grown in hydroponics at different NiSO4 levels Ni-accumulation occurred only at higher concentrations which, however, had a toxic effect. This peculiar combination of Ni-response traits could be the result of a partial evolutionary loss of ability with respect to all other Ni-accumulating congeneric species. For its unique characteristics, O. sibirica could therefore represent a unique model system for further studies on the evolutionary dynamics, physiological mechanisms and genetic control of metal accumulation and homeostasis. In a parallel study, we investigated photosynthesis responses of the same plants using an experimental approach. In non-hyperaccumulator plants, toxicity symptoms to above 10 μg g-1 DW nickel concentrations in soils can include inhibition of photosynthesis, impaired nitrogen assimilation and disturbed enzyme activity. However, there is a complete lack of information about how Ni-hyperaccumulators reconcile that extraordinary amount of metal in their shoots with an efficient photosynthetic activity, or at least on which photosynthetic parameters the excess of Ni impacts less in these plants. We measured Ni effects on growth, root and shoot metal accumulation and several photosynthetic parameters, such as gas exchange, chlorophyll fluorescence analyses and pigments content in three Odontarrhena taxa (two hyperaccumulators, one not) grown in hydroponics and exposed to three NiSO4 treatments. We found that Ni-hyperaccumulators species are photosynthetically more efficient under Ni excess in respect to the non-accumulating species. In fact, Ni treatment in O. chalcidica increased not only the photochemical efficiency of PSII and the CO2 assimilation rate, but also the stomatal conductance. Finally, this project focused on the determination of the activity of the enzyme urease, the only Nimetalloenzyme known so far in plants, in selected Odontarrhena taxa. The hypothesis to test was whether the high basal requirement for this micronutrient in these plants could be linked to a depletion of the Ni cytosolic pool at low external metal concentration, due to hyperaccumulation mechanism and impairing urease activity. To this purpose, enzyme activity and Ni shoot concentration were determined in plants of accumulating and non-accumulating taxa of Odontarrhena cultivated on Ni-rich serpentine soil and on garden soil, as well as in samples of O. bertolonii cultivated in hydroponics at increasing Ni concentrations. Odontarrhena hyperaccumulators showed similar urease activity when grown on both kinds of soils, with no relation between the enzyme activity and the leaf Ni accumulation. Contrarily, clear indications came from the experiment in controlled conditions, where the presence of Ni determined a progressive stimulation, in respect to control samples, of the activity of the enzyme, associated with an increase in shoot metal concentration. A significant relationship was found between the levels of urease activity and the amount of Ni accumulated in the leaves. Therefore, the already known Ni-stimulated growth of O. bertolonii at increasing metal concentrations in the low-dose zone could be explained by a Ni-induced activity of urease, associable to an enhanced nitrogen metabolism, unless other still unknown physiological functions of Ni in hyperaccumulating plants.
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10

Sobczyk, Maria Kinga. "Application of next-generation sequencing to analysis of the genetic basis of complex traits in plants, with particular focus on nickel hyperaccumulation in the Alyssum serpyllifolium species complex." Thesis, University of Oxford, 2015. https://ora.ox.ac.uk/objects/uuid:e4de8150-385e-44ec-b25d-2e60b1ea8604.

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Reliable, high-throughput and low-cost next-generation sequencing technologies have invigorated genetic research into non-model organisms over the last decade. In this work, RNA-Seq was employed to obtain the first-ever transcriptomes of two groups of closely related plant taxa possessing distinctive complex physiological traits, namely metal hyperaccumulation and C4 photosynthesis. Metal hyperaccumulator plants possess an extraordinary ability to take up trace elements from the soil and accumulate them to high concentrations in their shoots, probably to serve as a type of elemental defence against natural enemies. Taxonomically, the most common form of metal hyperaccumulation, nickel hyperaccumulation, is encountered on nickel-rich ultramafic (serpentine) soils, and is found with the highest frequency (ca. 51 species) in the genus Alyssum (family Brassicaceae). Here, the genetic basis and evolutionary history of nickel tolerance and hyperaccumulation was investigated in the Alyssum serpyllifolium Desf. species complex, which contains both serpentine and non-serpentine populations of unresolved phylogenetic relationships on the Iberian Peninsula. Genome scans for outlier loci and differential expression analyses identified a number of candidate hyperaccumulator genes common to two serpentine populations found in Portugal and Spain, but the majority of adaptive variation was of local origin. Phylogenetic and population-genetic inferences based on neutral and putatively adaptive loci suggested that the key genes for the nickel hyperaccumulation trait evolved once and spread across serpentine populations early in the history of this species, with no genetic isolation but continued recent gene flow between serpentine and non-serpentine populations. To test the power of next-generation sequencing for analysing the genetic basis of a separate complex trait, a cross-species comparison was performed using RNA-Seq of two congeneric tropical species, the C4 plant Alternanthera pungens Kunth and the C3 plant Alternanthera philoxeroides (Mart.) Griseb. f. angustifolia Suess. (family Amaranthaceae). These species were cultivated at two different temperatures and showed significant differences in levels of overall gene expression plasticity and isoform switching in certain photosynthesis genes, which it is proposed may explain the observed difference in the ability of these two species to acclimate to low and high growth temperatures.
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Begum, Mahmuda. "Habitat manipulation to enhance biological control of light brown apple moth (Epiphyas Postvittana)." Thesis, The University of Sydney, 2004. http://hdl.handle.net/2123/690.

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Trichogramma carverae Oatman and Pinto is mass-released for biological control of the leafroller pest, light brown apple moth, Epiphyas postvittana (Walker) in Australian vineyards. Parasitoid performance can, however, be constrained by a lack of suitable adult food and no information is available on the effect of nectar on the parasitism and longevity of T. carverae. To address this, the effect of alyssum, Lobularia maritima (L.) flowers on E. postvittana parasitism was studied in a vineyard experiment with and without releases of T. carverae. Egg parasitoid activity was assessed with E. postvittana egg 'sentinel cards' and no parasitism was recorded in plots without T. carverae releases. Where T. carverae were released, there was no significant enhancement of parasitism by the presence of L. maritima flowers. Three hypotheses were subsequently tested to account for the lack of an effect: (i) T. carverae does not benefit from L. maritima nectar, (ii) T. carverae was feeding on nectar from other flowering plants (weeds) present in the vineyard, (iii) T. carverae was feeding on sugars from ripe grapes. A growth-cabinet experiment using potted L. maritima plants with and without flowers did not support hypothesis one. No parasitism was recorded after day two for T. carverae caged without flowers whilst parasitism occured until day eight in the presence of flowers. A laboratory experiment with common vineyard weeds (Trifolium repens, Hypochoeris radicata, Echium plantagineum) as well as L. maritima did not support hypothesis one but gave partial support to hypothesis two. Survival of T. carverae was enhanced to a small but statistically significant extent in vials with intact flowers of L. maritima, white clover (T. repens) and catsear (H. radicata) but not in vials with flowering shoots of these species from which flowers and flowering buds had been removed. Paterson's curse (E. plantagineum) flowers had no effect on T. carverae survival. In a laboratory study, punctured grapes significantly enhanced T. carverae survival compared with a treatment without grapes, supporting hypothesis three. Trichogramma carverae performance in the field experiment was probably also constrained by relatively cool and wet weather. Further work on the enhancement of T. carverae efficacy by L. maritima and other carbohydrate sources is warranted. Greenhouse and field experiments were conducted to investigate whether T. carverae benefit from different groundcover plant species. Ten T. carverae adults (<24h after eclosion) were caged with different groundcover species and a control with no plant materials. Epiphyas postvittana egg sentinel cards were used to measure parasitism and longevity was recorded visually. Survival and realised parasitism of T. carverae was significantly higher in L. maritima than in Brassica juncea, Coriandrum sativum, shoots of these species from which flowers had been removed and nil control treatments. A similar experiment with Fagopyrum esculentum (with- and without-flowers) and a control treatment showed that survival was significantly higher in intact F. esculentum than in without-flower and control treatments. There was no significant treatment effect on parasitism in the early stages of that experiment, though parasitism was recorded in the presence of F. esculentum flowers for 12 days, compared with 6 days in other treatments. Higher parasitism was observed in intact Borago officinalis than in the flowerless shoot, water only and no plant material control treatments in a third experiment. There was no significant treatment effect on parasitism. Fitted exponential curves for survival data differed significantly in curvature in the first, second and third experiments but the slope was a non-significant parameter in the second and third experiments. In a second series of laboratory experiments, one male and one female T. carverae were caged with groundcover species to investigate male and female longevity and daily fecundity. Both male and female longevity in F. esculentum and L. maritima treatments were significantly higher than on shoots of these species from which flowers had been removed, and than in the control treatments. Daily fecundity was significantly greater in the intact L. maritima treatment than in all other treatments. Fitted exponential curves for daily fecundity differed significantly in position and slope but not in curvature. There was no significant treatment effect on longevity or parasitism when a male and female were caged with intact B. juncea, B. officinalis or without-flower of these species, nor in the treatment with no plant materials. No parasitism was observed in a survey of naturally occurring egg parasitoids on two sites close to Orange and Canowindra in New South Wales, illustrating the importance of mass releases of T. carverae in biological control of E. postvittana. In an experiment on the Canowindra site, parasitism was significantly higher on day one and day two after T. carverae release when with-flower treatments were compared with without-flower treatments. Parasitism was significantly higher in the F. esculentum treatment than in C. sativum, L. maritima, vegetation without-flowers and control treatments on these dates. On day five, parasitism was higher in C. sativum than in all other treatments. There was no significant increase in parasitism in a second experiment conducted on the Orange site. Coriandrum sativum, F. esculentum and L. maritima appear to be suitable adult food sources for T. carverae and offer some scope for habitat manipulation in vineyards The adults of many parasitoid species require nectar for optimal fitness but very little is known about flower recognition. Flight cage experiments showed that the adults of T. carverae benefited from L. maritima bearing white flowers to a greater extent than was the case for light pink, dark pink or purple flowered cultivars, despite all cultivars producing nectar. Survival and realised parasitism on non-white flowers were no greater than when the parasitoids were caged on L. maritima shoots from which flowers had been removed. The possibility that differences between L. maritima cultivars were due to factors other than flower colour, such as nectar quality, was excluded by dyeing white L. maritima flowers by placing the roots of the plants in 5% food dye (blue or pink) solution. Survival of T. carverae was lower on dyed L. maritima flowers than on undyed white flowers. Mixing the same dyes with honey in a third experiment conducted in the dark showed that the low level of feeding on dyed flowers was unlikely to be the result of olfactory or gustatory cues. Flower colour appears, therefore, to be a critical factor in the choice of plants used to enhance biological control, and is likely to also be a factor in the role parasitoids play in structuring invertebrate communities. Provision of nectar producing plants to increase the effectiveness of biological control is one aspect of habitat manipulation, but care needs to be taken to avoid the use of plant species that may benefit pest species. Greenhouse experiments were conducted to investigate whether the adult E. postvittana and larvae benefit from nectar producing groundcover species. Newly emerged E. postvittana adults were caged with different groundcover species and a honey-based artificial adult diet. The longevity of male and female E. postvittana when caged with shoots of borage (B. officinalis) and buckwheat (F. esculentum) bearing flowers was as long as when fed a honey-based artificial diet. This effect was not evident when caged with shoots of these plants from which flowers had been removed. Longevity was significantly lower than in the artificial diet treatment when caged with coriander (C. sativum) or alyssum (L. maritima) irrespective of whether flowers were present or not. There was no significant treatment effect on the lifetime fecundity of E. postvittana. A second experiment with mustard (B. juncea) (with- and without-flowers), water only and honey-based artificial adult diet showed no significant treatment effects on the longevity of male and female E. postvittana or on the lifetime fecundity of E. postvittana. The anomalous lack of a difference between the water and honey-based diet treatments precludes making conclusions on the value of B. juncea for E. postvittana. Two greenhouse experiments were conducted to evaluate the effects of groundcover species on the larval development of E. postvittana. In the first experiment, larval mortality was significantly higher in C. sativum, and L. maritima than in B. juncea, B. officinalis and white clover (T. repens) a known host of E. postvittana. Coriandrum sativum and L. maritima extended the larval period. In B. juncea and B. officinalis, mortality did not differ from that in T. repens. In F. esculentum, larval mortality was significantly higher than in T. repens. A short larval period was observed on B. juncea, B. officinalis and F. esculentum. Fitted exponential curves for larval mortality differed significantly in curvature between plant treatments. Similarly, successful pupation was significantly lower in C. sativum, F. esculentum and L. maritima than in T. repens. The percentage of successful pupation in B. juncea and B. officinalis did not differ from F. esculentum and T. repens. Fitted exponential curves for pupation differed significantly in curvature. A similar trend was observed in a second experiment with potted plants. The overall results suggest that C. sativum and L. maritima denied benefit to E. postvittana adults and larvae, so could be planted as vineyard groundcover with minimal risk of exacerbating this pest. Overall results suggest that T. carverae require nutrients to reach their full reproductive potential and flowers provide such nutrients. Lobularia maritima and C. sativum may be considered 'selective food plants' for T. carverae whereas F. esculentum appears to be a 'non-selective food plant'; both T. carverae and E. postvittana benefited from it. Fruits such as grapes can be used as food resources in habitat manipulation and this merits further research. This result also suggests that within species flower colour is an important factor for flower selection in habitat manipulation.
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12

Begum, Mahmuda. "Habitat manipulation to enhance biological control of light brown apple moth (Epiphyas Postvittana)." University of Sydney. Rural Management, 2004. http://hdl.handle.net/2123/690.

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Trichogramma carverae Oatman and Pinto is mass-released for biological control of the leafroller pest, light brown apple moth, Epiphyas postvittana (Walker) in Australian vineyards. Parasitoid performance can, however, be constrained by a lack of suitable adult food and no information is available on the effect of nectar on the parasitism and longevity of T. carverae. To address this, the effect of alyssum, Lobularia maritima (L.) flowers on E. postvittana parasitism was studied in a vineyard experiment with and without releases of T. carverae. Egg parasitoid activity was assessed with E. postvittana egg �sentinel cards� and no parasitism was recorded in plots without T. carverae releases. Where T. carverae were released, there was no significant enhancement of parasitism by the presence of L. maritima flowers. Three hypotheses were subsequently tested to account for the lack of an effect: (i) T. carverae does not benefit from L. maritima nectar, (ii) T. carverae was feeding on nectar from other flowering plants (weeds) present in the vineyard, (iii) T. carverae was feeding on sugars from ripe grapes. A growth-cabinet experiment using potted L. maritima plants with and without flowers did not support hypothesis one. No parasitism was recorded after day two for T. carverae caged without flowers whilst parasitism occured until day eight in the presence of flowers. A laboratory experiment with common vineyard weeds (Trifolium repens, Hypochoeris radicata, Echium plantagineum) as well as L. maritima did not support hypothesis one but gave partial support to hypothesis two. Survival of T. carverae was enhanced to a small but statistically significant extent in vials with intact flowers of L. maritima, white clover (T. repens) and catsear (H. radicata) but not in vials with flowering shoots of these species from which flowers and flowering buds had been removed. Paterson�s curse (E. plantagineum) flowers had no effect on T. carverae survival. In a laboratory study, punctured grapes significantly enhanced T. carverae survival compared with a treatment without grapes, supporting hypothesis three. Trichogramma carverae performance in the field experiment was probably also constrained by relatively cool and wet weather. Further work on the enhancement of T. carverae efficacy by L. maritima and other carbohydrate sources is warranted. Greenhouse and field experiments were conducted to investigate whether T. carverae benefit from different groundcover plant species. Ten T. carverae adults (<24h after eclosion) were caged with different groundcover species and a control with no plant materials. Epiphyas postvittana egg sentinel cards were used to measure parasitism and longevity was recorded visually. Survival and realised parasitism of T. carverae was significantly higher in L. maritima than in Brassica juncea, Coriandrum sativum, shoots of these species from which flowers had been removed and nil control treatments. A similar experiment with Fagopyrum esculentum (with- and without-flowers) and a control treatment showed that survival was significantly higher in intact F. esculentum than in without-flower and control treatments. There was no significant treatment effect on parasitism in the early stages of that experiment, though parasitism was recorded in the presence of F. esculentum flowers for 12 days, compared with 6 days in other treatments. Higher parasitism was observed in intact Borago officinalis than in the flowerless shoot, water only and no plant material control treatments in a third experiment. There was no significant treatment effect on parasitism. Fitted exponential curves for survival data differed significantly in curvature in the first, second and third experiments but the slope was a non-significant parameter in the second and third experiments. In a second series of laboratory experiments, one male and one female T. carverae were caged with groundcover species to investigate male and female longevity and daily fecundity. Both male and female longevity in F. esculentum and L. maritima treatments were significantly higher than on shoots of these species from which flowers had been removed, and than in the control treatments. Daily fecundity was significantly greater in the intact L. maritima treatment than in all other treatments. Fitted exponential curves for daily fecundity differed significantly in position and slope but not in curvature. There was no significant treatment effect on longevity or parasitism when a male and female were caged with intact B. juncea, B. officinalis or without-flower of these species, nor in the treatment with no plant materials. No parasitism was observed in a survey of naturally occurring egg parasitoids on two sites close to Orange and Canowindra in New South Wales, illustrating the importance of mass releases of T. carverae in biological control of E. postvittana. In an experiment on the Canowindra site, parasitism was significantly higher on day one and day two after T. carverae release when with-flower treatments were compared with without-flower treatments. Parasitism was significantly higher in the F. esculentum treatment than in C. sativum, L. maritima, vegetation without-flowers and control treatments on these dates. On day five, parasitism was higher in C. sativum than in all other treatments. There was no significant increase in parasitism in a second experiment conducted on the Orange site. Coriandrum sativum, F. esculentum and L. maritima appear to be suitable adult food sources for T. carverae and offer some scope for habitat manipulation in vineyards The adults of many parasitoid species require nectar for optimal fitness but very little is known about flower recognition. Flight cage experiments showed that the adults of T. carverae benefited from L. maritima bearing white flowers to a greater extent than was the case for light pink, dark pink or purple flowered cultivars, despite all cultivars producing nectar. Survival and realised parasitism on non-white flowers were no greater than when the parasitoids were caged on L. maritima shoots from which flowers had been removed. The possibility that differences between L. maritima cultivars were due to factors other than flower colour, such as nectar quality, was excluded by dyeing white L. maritima flowers by placing the roots of the plants in 5% food dye (blue or pink) solution. Survival of T. carverae was lower on dyed L. maritima flowers than on undyed white flowers. Mixing the same dyes with honey in a third experiment conducted in the dark showed that the low level of feeding on dyed flowers was unlikely to be the result of olfactory or gustatory cues. Flower colour appears, therefore, to be a critical factor in the choice of plants used to enhance biological control, and is likely to also be a factor in the role parasitoids play in structuring invertebrate communities. Provision of nectar producing plants to increase the effectiveness of biological control is one aspect of habitat manipulation, but care needs to be taken to avoid the use of plant species that may benefit pest species. Greenhouse experiments were conducted to investigate whether the adult E. postvittana and larvae benefit from nectar producing groundcover species. Newly emerged E. postvittana adults were caged with different groundcover species and a honey-based artificial adult diet. The longevity of male and female E. postvittana when caged with shoots of borage (B. officinalis) and buckwheat (F. esculentum) bearing flowers was as long as when fed a honey-based artificial diet. This effect was not evident when caged with shoots of these plants from which flowers had been removed. Longevity was significantly lower than in the artificial diet treatment when caged with coriander (C. sativum) or alyssum (L. maritima) irrespective of whether flowers were present or not. There was no significant treatment effect on the lifetime fecundity of E. postvittana. A second experiment with mustard (B. juncea) (with- and without-flowers), water only and honey-based artificial adult diet showed no significant treatment effects on the longevity of male and female E. postvittana or on the lifetime fecundity of E. postvittana. The anomalous lack of a difference between the water and honey-based diet treatments precludes making conclusions on the value of B. juncea for E. postvittana. Two greenhouse experiments were conducted to evaluate the effects of groundcover species on the larval development of E. postvittana. In the first experiment, larval mortality was significantly higher in C. sativum, and L. maritima than in B. juncea, B. officinalis and white clover (T. repens) a known host of E. postvittana. Coriandrum sativum and L. maritima extended the larval period. In B. juncea and B. officinalis, mortality did not differ from that in T. repens. In F. esculentum, larval mortality was significantly higher than in T. repens. A short larval period was observed on B. juncea, B. officinalis and F. esculentum. Fitted exponential curves for larval mortality differed significantly in curvature between plant treatments. Similarly, successful pupation was significantly lower in C. sativum, F. esculentum and L. maritima than in T. repens. The percentage of successful pupation in B. juncea and B. officinalis did not differ from F. esculentum and T. repens. Fitted exponential curves for pupation differed significantly in curvature. A similar trend was observed in a second experiment with potted plants. The overall results suggest that C. sativum and L. maritima denied benefit to E. postvittana adults and larvae, so could be planted as vineyard groundcover with minimal risk of exacerbating this pest. Overall results suggest that T. carverae require nutrients to reach their full reproductive potential and flowers provide such nutrients. Lobularia maritima and C. sativum may be considered �selective food plants� for T. carverae whereas F. esculentum appears to be a �non-selective food plant�; both T. carverae and E. postvittana benefited from it. Fruits such as grapes can be used as food resources in habitat manipulation and this merits further research. This result also suggests that within species flower colour is an important factor for flower selection in habitat manipulation.
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13

Frantz, Alysson. "Uso de Rede Bayesiana na probabilidade de óbito em Unidade de Terapia Intensiva / Alysson Frantz ; orientadora, Andreia Malucelli." reponame:Biblioteca Digital de Teses e Dissertações da PUC_PR, 2008. http://www.biblioteca.pucpr.br/tede/tde_busca/arquivo.php?codArquivo=1344.

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Dissertação (mestrado) - Pontifícia Universidade Católica do Paraná, Curitiba, 2008
Bibliografia: f. 107-112
O prognóstico de doenças, assim como o seu diagnóstico e tratamento, faz parte dos cuidados prestados pelo profissional de saúde, sendo que, para determinar a probabilidade de óbito de pacientes devem-se considerar as idiossincrasias populacionais, as dif
The prognostics of illnesses, as well as their diagnosis and treatment, are part of the care taken by the health professional. In order to determine the death probability of patients, it is necessary to consider the population idiosyncrasies, the differen
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14

Pettey, Alyssa A. "EXAMINING WORK-FAMILY CONFLICT AND PARENTING STRESS FOR PARENTS OF CHILDREN WITH AUTISM SPECTRUM DISORDER THROUGH THE LENS OF BOUNDARY AND CONSERVATIONS OF RESOURCES THEORIES." CSUSB ScholarWorks, 2015. https://scholarworks.lib.csusb.edu/etd/231.

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Understanding the challenges parents of children with disabilities face when seeking to balance work and family is a real concern; however, these challenges have not been well studied. Parents of children with disabilities experience excess challenges in the home domain as a result of their caregiving demands that can lead to challenges in balancing family and work. This is particularly problematic for parents raising children with autism spectrum disorder (ASD). The present study examined the relationship between inter-domain transitions and work-family conflict in order to identify personal and situational factors that were associated with reduced conflict and parenting stress in a population of parents raising children with ASD. Results of this study demonstrated the importance of individuals’ appraisal of transitions on the relationships between inter-domain transitions and work-family conflict and inter-domain transitions and parenting stress. Further, family-supportive supervisor behaviors and segmentation preferences mitigated the experiences of WFC and parenting stress for this population. The results of this study provide important implications for organizations in seeking to help parents of children with ASD more effectively balance their work and family domains.
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15

Velli, Andrea <1984&gt. "Relationships between plant diversity and environmental heterogeneity in rupicolous grasslands on gypsum. The case study of Alysso-Sedion albi (Habitat 6110)." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amsdottorato.unibo.it/6493/1/Velli_Andrea_Tesi.pdf.

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Plant communities on weathered rock and outcrops are characterized by high values in species richness (Dengler 2006) and often persist on small and fragmented surfaces. Yet very few studies have examined the relationships between heterogeneity and plant diversity at small scales, in particular in poor-nutrient and low productive environment (Shmida and Wilson 1985, Lundholm 2003). In order to assess these relationships both in space and time in relationship, two different approaches were employed in the present study, in two gypsum outcrops of Northern Apennine. Diachronic and synchronic samplings from April 2012 to March 2013 were performed. A 50x50 cm plot was used in both samplings such as the sampling unit base. The diachronic survey aims to investigate seasonal patterning of plant diversity by the use of images analysis techniques integrated with field data and considering also seasonal climatic trend, the substrate quality and its variation in time. The purpose of the further, synchronic sampling was to describe plant diversity pattern as a function of the environmental heterogeneity meaning in substrate typologies, soil depth and topographic features. Results showed that responses of diversity pattern depend both on the resources availability, environmental heterogeneity and the manner in which the different taxonomic group access to them during the year. Species richness and Shannon diversity were positively affected by increasing in substrate heterogeneity. Furthermore a good turnover in seasonal species occurrence was detected. This vegetation may be described by the coexistence of three groups of species which created a gradient from early colonization stages, characterized by greater slope and predominance of bare rock, gradually to situation of more developed soil.
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16

Velli, Andrea <1984&gt. "Relationships between plant diversity and environmental heterogeneity in rupicolous grasslands on gypsum. The case study of Alysso-Sedion albi (Habitat 6110)." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amsdottorato.unibo.it/6493/.

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Plant communities on weathered rock and outcrops are characterized by high values in species richness (Dengler 2006) and often persist on small and fragmented surfaces. Yet very few studies have examined the relationships between heterogeneity and plant diversity at small scales, in particular in poor-nutrient and low productive environment (Shmida and Wilson 1985, Lundholm 2003). In order to assess these relationships both in space and time in relationship, two different approaches were employed in the present study, in two gypsum outcrops of Northern Apennine. Diachronic and synchronic samplings from April 2012 to March 2013 were performed. A 50x50 cm plot was used in both samplings such as the sampling unit base. The diachronic survey aims to investigate seasonal patterning of plant diversity by the use of images analysis techniques integrated with field data and considering also seasonal climatic trend, the substrate quality and its variation in time. The purpose of the further, synchronic sampling was to describe plant diversity pattern as a function of the environmental heterogeneity meaning in substrate typologies, soil depth and topographic features. Results showed that responses of diversity pattern depend both on the resources availability, environmental heterogeneity and the manner in which the different taxonomic group access to them during the year. Species richness and Shannon diversity were positively affected by increasing in substrate heterogeneity. Furthermore a good turnover in seasonal species occurrence was detected. This vegetation may be described by the coexistence of three groups of species which created a gradient from early colonization stages, characterized by greater slope and predominance of bare rock, gradually to situation of more developed soil.
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17

Petersen, Alyssa [Verfasser], and Rüdiger [Akademischer Betreuer] Korbel. "Influence of blood storage time and temperature on the evaluation of blood smears from Hermann’s tortoises (Testudo hermanni) / Alyssa Petersen ; Betreuer: Rüdiger Korbel." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2016. http://d-nb.info/1136570292/34.

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18

Berndt, Lisa A. "The effect of floral resources on the leafroller (Lepidoptera: Tortricidae) parasitoid Dolichogenidea tasmanica (Cameron)(Hymenoptera: Braconidae) in selected New Zealand vineyards." Lincoln University, 2002. http://hdl.handle.net/10182/1045.

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In this study, buckwheat (Fagopyrum esculentum Moench) and alyssum (Lobularia maritima (L.)) flowers were used to examine the effect of floral resources on the efficacy of the leafroller parasitoid Dolichogenidea tasmanica (Cameron) in vineyards. This was done by assessing the influence of these flowers on parasitoid abundance and parasitism rate, and by investigating the consequences of this for leafroller abundance. In laboratory experiments, alyssum flowers were used to investigate the effect of floral food on the longevity, fecundity and sex ratio of D. tasmanica. Dolichogenidea tasmanica comprised more than 95 % of parasitoids reared from field collected leafrollers in this study. The abundance of D. tasmanica during the 1999-2000 growing season was very low compared with previous studies, possibly due to the very low abundance of its leafroller hosts during the experiment. The number of males of this species on yellow sticky traps was increased (although not significantly) when buckwheat flowers were planted in a Marlborough vineyard; however, the number of female D. tasmanica on traps was no greater with flowers than without. The abundance of another leafroller parasitoid, Glyptapanteles demeter (Wilkinson)(Hymenoptera: Braconidae), on traps was also not significantly affected by the presence of buckwheat flowers, although females of this species were caught in greater numbers in the control than in buckwheat plots. Naturally-occurring leafrollers were collected from three vineyard sites in Marlborough, and one in Canterbury during the 2000-2001 season to assess the effect of buckwheat and alyssum flowers on parasitism rate. Parasitism rate more than doubled in the presence of buckwheat at one of the Marlborough vineyards, but alyssum had no effect on parasitism rate in Canterbury. A leafroller release/recover method, used when naturally-occurring leafrollers were too scarce to collect, was unable to detect any effect of buckwheat or alyssum on parasitism rate. Mean parasitism rates of approximately 20 % were common in Marlborough, although rates ranged from 0 % to 45 % across the three vineyard sites in that region. In Canterbury in April, mean parasitism rates were approximately 40 % (Chapter 4). Rates were higher on upper canopy leaves (40-60 %) compared with lower canopy leaves and bunches (0-25 %). Leafroller abundance was apparently not affected by the presence of buckwheat in Marlborough, or alyssum in Canterbury. Buckwheat did, however, significantly reduce the amount of leafroller evidence (webbed leafroller feeding sites on leaves or in bunches) in Marlborough, suggesting that the presence of these flowers may reduce leafroller populations. Leafrollers infested less than 0.1 % of Cabernet Sauvignon leaves throughout the 1999-2000 growing season, but increased in abundance in bunches to infest a maximum of 0.5 % of bunches in late March in Marlborough. In Pinot Noir vines in the 2000-2001 season, leafroller abundance was also low, although sampling was not conducted late in the season when abundance reaches a peak. In Riesling vines in Canterbury, between 1.5 % and 2.5 % of bunches were infested with leafrollers in April. In the laboratory, alyssum flowers significantly increased the longevity and lifetime fecundity of D. tasmanica compared with a no-flower treatment. However, daily fecundity was not increased by the availability of food, suggesting that the greater lifetime fecundity was related to increases in longevity. Parasitoids were also able to obtain nutrients from whitefly honeydew, which resulted in similar longevity and daily fecundity to those when alyssum flowers were present. The availability of food had a significant effect on the offspring sex ratio of D. tasmanica. Parasitoids reared from naturally-occurring leafrollers produced an equal sex ratio, assumed to be the evolutionarily stable strategy (ESS) for this species. In the laboratory, this ESS was observed only when parasitoids had access to alyssum flowers. Without food, or with honeydew only, sex ratios were strongly male-biased. In the field, floral resources affected the sex ratio of D. tasmanica only when this species was reared from leafrollers released and recovered in Marlborough. In that experiment, buckwheat shifted the sex ratio in favour of female production from the equal sex ratio found in control plots. No firm explanations can be given to account for these results, due to a lack of research in this area. Possible mechanisms for the changes in sex ratio with flowers are discussed. This study demonstrated that flowers are an important source of nutrients for D. tasmanica, influencing the longevity, fecundity and offspring sex ratio of this species. However, only some of the field experiments were able to show any positive effect of the provision of floral resources on parasitoid abundance or parasitism rate. More information is needed on the role these parasitoids, and other natural enemies, play in regulating leafroller populations in New Zealand vineyards, and on how they use floral resources in the field, before recommendations can be made regarding the adoption of this technology by growers.
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19

Barkman, Rebecca, and Mikael Fält. "Wow… That Escalated Quickly : En studie i grunderna hos en oplanerad viral kampanj på sociala medier." Thesis, Mittuniversitetet, Institutionen för medie- och kommunikationsvetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-39280.

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Sammanfattning: Det mest märkbara resultatet i studien är att det inte krävs en stor aktör med många följare för att påbörja en stor kampanj, men det är nödvändigt att få hjälp av dem för att nå en viral spridning. De två studerade kampanjerna hade helt olika sätt att kommunicera på, där MeToo hade en allvarsam ton och Ice Bucket Challenge ett humoristiskt och positivt laddat budskap - båda om smärtsamma ämnen. Eftersom de båda blev virala visar resultatet att det viktigaste är ett känslomässigt laddat budskap som påverkar folk, oavsett om det är glada, ilskna eller sorgsna känslor. Det krävs stark känslomässig påverkan för att personer ska känna sig motiverade att sprida vidare ett budskap. Samhällsklimatet och aktuella samhällsfrågor kan hjälpa en kampanj bli viral, men är inte nödvändig. Det finns ingen specifik riktlinje eller mall att följa för att bli viral, men det är viktigt att ha hög spridbarhet på sitt budskap och motivera mottagaren att dela vidare.
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20

Verma, Tarishi. "The Legitimacy of Online Feminist Activism: Subversion of Shame in Sexual Assault by Reporting it on Social Media." Bowling Green State University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1617396334881314.

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21

Sonet, Sanjay Saha. "Do hyper-accumula tor plants make good neighbours?" Master's thesis, 2014. http://hdl.handle.net/10316/33293.

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Dissertação de Mestrado em Ecologia apresentada à Faculdade de Ciências e Tecnologia da Universidade de Coimbra.
As plantas hiper-acumuladores podem ser encontradas em muitos tipos de solos com altas concentrações de metais, tais como afloramentos de serpentina. Ainda existe uma lacuna de conhecimento ao nível da comunidade de insectos nestas regiões. Estudos anteriores focaram-se principalmente em testes laboratoriais e concentraram-se na defesa das plantas contra o ataque herbívoro, enquanto outros estudos realizados procuraram compreender em estudos de campo qual relevância das plantas híper-acumuladoras e os insetos que potencialmente se alimentam delas (ao nível da comunidade). Além disso, a contribuição do fluxo de metais pesados das plantas hiperacumuladores para um diferente nível trófico (herbívoros e carnívoros) tem sido referida por vários estudos. No presente trabalho, o efeito da híper-acumulação de metais pesados na herbivoria de uma planta bioacumuladora e das espécies que ocorrem ao mesmo tempo foi avaliada. A hipótese é que a bioacumulação de Ni irá reduzir a diversidade e abundância de herbívoros e, como consequência, as plantas híper-acumuladoras irão interagir com um subconjunto de herbívoros distinto das outras plantas da comunidade. Alyssum pintodasilvae, uma conhecida planta híper-acumulador de níquel, foi escolhida para este estudo, pois é endêmica e altamente abundante nas áreas serpentínicas do Nordeste de Portugal. O trabalho de campo foi realizado na zona serpentínica de Samil, Bragança (NE Portugal), tendo sido definidos três locais de sucessão de vegetação nesta área. Foram realizadas quatro visitas ao local e registadas todas as interações planta-animal em cada site. As plantas foram identificadas (no campo e no laboratório) e os insectos foram capturados e levados para o laboratório para serem morfotipados/identificados, enquanto redes ecológicas foram utilizadas para avaliar as interações bióticas neste ecossistema. Os resultados obtidos descreveram a presença de 38 espécies de plantas (35 géneros, 20 famílias) e 192 espécies de insectos, representando 10 ordens diferentes. No total, 122 diferentes insectos herbívoros foram colectados de 29 plantas diferentes, revelando um total de 621 interações e 213 links. A maioria destes eram Coleoptera (34), Hymenoptera (25), Hemiptera (24), e Lepidoptera (21), enquanto que outros, como Orthoptera (8), Diptera (4), Thysanoptera (1) e Isoptera (1), foram encontrados em menor quantidade. Os únicos parâmetros para os quais A. pintodasilvae se destaca como significativamente diferente do que as plantas não-acumuladoras é que esta tem um grau maior (isto é, mais parceiros), e força de espécies e proporcionalidade similares. As espécies de insectos mais interligados com a planta híper-acumulador de níquel (A. pintodasilvae) foram duas ninfas de Hemiptera da família Miridae, e uma de larva de Coleoptera da família Chrysomelidae, porém não foi encontrada nenhuma evidência para o papel da híper-acumulação de níquel na "herbivoria" ao nível da comunidade. Este estudo permite concluir que os padrões de interação de A. pintodasilvae dentro da comunidade não são diferentes do que os das plantas nãohíper- acumuladoras.
Hyper-accumulator plants can be found in many types of soils with high concentrations of metals, including in serpentine outcrops. A knowledge gap still exists at the insect community level in these regions. Former studies have focused mainly in laboratory research and have focused on defence against herbivore attack, while few studies have been performed to understand in the field the relevance of the hyper-accumulator plants and the insects potentially feeding on them (at the community level). Moreover, contribution of the flux of metal by hyper-accumulator plants to a different trophic level (herbivore and carnivore level) have also has been reported by several studies. In this work, the effect of heavy-metal hyper-accumulation at the herbivory level of an accumulator plant and its co-occurring species has been evaluated. The hypothesis is that Ni accumulation will reduce the diversity and abundance of herbivores, and as a consequence hyper-accumulator plants will interact with a distinct subset of the herbivores of the other plants in the community. Alyssum pintodasilvae, a recognised Ni hyper-accumulator, is endemic and highly abundant in the northeastern serpentine areas of Portugal, and was chosen for this study. The field work was performed in the serpentine area of Samil, Bragança (NE Portugal), and three vegetation succession sites were defined in this area. Four visits were performed and plant-animal interactions were registered in each site. Plants were identified (in the field and in the laboratory) and insects were collected for latter morphotyping/identification, and ecological networks were used to assess the biotic interactions in this ecosystem. Results have described the presence of 38 species of plant (35 genus, 20 families) and 192 insect species, representing 10 different orders. In total, 122 different herbivorous insects were collected from 29 different plants, revealing a total of 621 interactions and 213 links. Most of them were from Coleoptera (34), Hymenoptera (25), Hemiptera (24), and Lepidoptera (21) while fewer were from Orthoptera (8), Diptera (4), Thysanoptera (1) and Isoptera (1). The only parameters for which A. pintodasilvae stands out as significantly different than the non-accumulator plants is in that it has a higher degree (i.e. more partners), species' strength and proportional similarity. The higher interlinked insect species of Ni hyper-accumulators (A. pintodasilvae) were two Hemiptera nymphs from the Miridae family, and a Coleoptera larvae from the Chrysomelidae family, however no evidence for a role of Ni hyper-accumulation on “herbivory” at the community level was found. The study concluded that the interaction patterns of A. pintodasilvae within the community are no different than for the non-hyper-accumulator plants.
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22

Alves, Ana Rita Almeida. "Otimização do processo de fitomineração de níquel com a espécie Alyssum pintodasilvae através de corretivos orgânicos." Master's thesis, 2020. http://hdl.handle.net/10773/30580.

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A fitomineração é uma fitotecnologia recente, “amiga do ambiente”, que consiste na utilização de plantas hiperacumuladoras (espécies que acumulam grandes concentrações de metais nas partes aéreas), para recuperação de metais valiosos a partir de solos mineralizados ou contaminados. A fitomineração de níquel, em particular, tem recebido muita atenção nos últimos anos por ser bastante promissora. Contudo, existem limitações no processo, sendo que, de forma a tirar um maior partido desta fitotecnologia, é oportuno a realização de estudos com a aplicação de diferentes práticas agrícolas, para que, as que tornam o processo mais rentável sejam incorporadas nestes sistemas no futuro. Nesse sentido, dada a existência de uma espécie hiperacumuladora de níquel (Alyssum pintodasilvae) endémica de Portugal, foi testado o efeito da aplicação de corretivos orgânicos no rendimento da mesma na fitomineração. O principal objetivo deste trabalho foi determinar quais os corretivos mais vantajosos (biochar, lodo industrial e esterco de porco), para otimização do processo de fitomineração com esta espécie. Foram recolhidas sementes da espécie A. pintodasilvae e solos do maciço de Morais, que corresponde a uma área ultramáfica em Portugal. Aplicaram-se diferentes concentrações de corretivos orgânicos aos solos, mais precisamente tratamentos de 1.5 e 3% biochar (B1.5 e B3), que também foram testadas com 1% de lodo industrial (B1.5SL e B3SL) e para outros tratamentos com 1% de esterco de porco (B1.5PS e B3PS). As plantas cresceram nestes solos, em laboratório, sob condições controladas. Posteriormente, foram realizadas diversas análises aos solos e plantas de forma a compreender como os corretivos afetaram o rendimento em biomassa e acumulação em níquel por parte da planta. Concluiu-se que os tratamentos em que foi aplicado biochar juntamente com lodo industrial (B1.5SL e B3SL) são promissores, principalmente o tratamento B3SL, por melhorar as propriedades do solo e proporcionar uma quantidade maior de macro e micronutrientes importantes para as plantas. O biochar isoladamente não surtiu efeito significativo no rendimento da fitomineração e a aplicação de esterco de porco produziu resultados negativos devido à elevada salinidade deste corretivo.
Phytomining is a recent, “environment friendly” phytotechnology, that consists in the use of hyperaccumulator plants (species that can accumulate high concentrations of metals in their shoots), for recovery of metals from mineralized or contaminated soils. Particularly, nickel phytomining has received in the last years, much attention due to its promising results. However, there are limitations to the phytomining process and therefore it is important the study of agricultural practices which can be implemented in the future to make the process more profitable. Taking this into account, since there is a nickel hyperaccumulator specie (Alyssum pintodasilvae) endemic to Portugal, we tested the effect of organic amendments in the phytomining yield. The major objective of this work was to determine which are the most appropriate amendments (biochar, industrial sludge and pig slurry), for optimizing the nickel phytomining process with this species. Seeds of A. pintodasilvae and soil samples were collected from the Morais massif, that constitutes an ultramafic area in Portugal. Different concentrations of organic amendments in the soil were tested, resulting in treatments with 1.5 and 3% biochar (B1.5 and B3), that were also tested with 1% industrial sludge (B1.5SL and B3SL) and with 1% of pig slurry for other treatments (B1.5PS and B3PS). The plants were grown in these soils, in the laboratory, under controlled conditions. Afterwards, soils and plants were analysed to determine how the amendments affected the plant biomass and nickel accumulation yield. The treatments in which were introduced both, biochar and industrial sludge (B1.5SL and B3SL), are promising, particularly the one B3SL, since it improves soil properties and provides a higher amount of macro and micronutrients important to plants. While there were no significant differences in the phytomining yield with the application of biochar alone, pig slurry had a negative effect in the plants due to the high salinity levels of this organic amendment.
Mestrado em Geomateriais e Recursos Geológicos
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Santos, Daniela Sofia Aguiar dos. "Testes de não-escolha em Porcellio dilatatus sujeitos a dieta de folhas de Alyssum spp. com diferentes concentrações de Ni." Master's thesis, 2013. http://hdl.handle.net/10316/24616.

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Dissertação de mestrado em Biologia, apresentada ao Departamento Ciências da Vida da Faculdade de Ciências e Tecnologia da Universidade de Coimbra
A hiperacumulação de metais é um fenómeno que ocorre principalmente em solos ultramáficos ou serpentínicos, ricos em minerais ferromagnésicos e caracterizados por um pH de 6,5 – 8, predomínio de Mg em relação ao Ca e teores muito baixos de P, N e K. Em Portugal, este tipo de solo ocorre apenas em Trás-os-Montes, em diversos afloramentos de áreas reduzidas. Alyssum pintodasilvae, uma das espécies endémicas desses solos, é a única hiperacumuladora de Ni conhecida no país. Alyssum simplex é outra espécie endémica de solos serpentínicos, de distribuição mais reduzida e que não acumula Ni. Para avaliar se a hiperacumulação de níquel em A. pintodassilvae constitui uma defesa elementar contra a herbívora, realizaram-se ensaios com Porcellio dilatatus, um isópode detritívoro representativo do nível trófico dos macrodecompositores. Os isópodes foram alimentados com folhas condicionadas das seguintes espécies: A. pintodasilvae (colhido no afloramento serpentínico de Alimonde, Bragança), A. simplex (colhido no afloramento serpentínico de Carrazedo, Bragança), Alnus glutinosa como controlo positivo e de A. pintodasilvae cultivado em laboratório sem Ni. Os isópodes foram alimentados durante 32 dias, sob condições controladas de humidade e temperatura. Os resultados obtidos mostraram que A. pintodasilvae induziu elevada mortalidade dos isópodes relativamente às outras espécies de plantas utilizadas, principalmente A. Pintadasilvae in vitro e Alnus glutinosa. Estes resultados indicam que o Ni exerce um efeito tóxico nos isópodes detritívoros e, portanto, atua como defesa elementar em A. pintodasilvae. Os resultados obtidos com A. simplex sugerem um efeito anti-herbivoria algo idêntico a A. pintodasilvae, uma vez que não foram detetadas diferenças significativas entre o efeito das duas espécies para os parâmetros avaliados. Os resultados sugerem a existência, em A. Simplex, de um mecanismo de defesa anti-herbivoria, como por exemplo compostos fenólicos ou glucosinolatos, que poderá não ser tão eficaz como a hiperacumulação de Ni em A. pintodasilvae.
Metal hyperaccumulation is a phenomenon that occurs mainly in ultramafic and serpentine soils, rich in ferromagnesic minerals and characterized by pH 6.5 - 8, predominancy of Mg towards Ca and very low levels of P, N and K. In Portugal, this soil type occurs only in Trás-os-Montes, in several outcrops of small areas. Alyssum pintodasilvae, one of the endemic species of these soils, is the only known hyperaccumulator of Ni in the country.. Alyssum simplex is another species endemic to serpentine soil, with a lower distribution and does not accumulate Ni. To assess whether the hyperaccumulation of nickel in A. pintodassilvae is an elemental defense against herbivores, assays were performed with Porcellio dilatatus, a scavenger isopod representative of the macrodecomposers trophic level. The isopods were fed conditioned leaves of the following species: A. pintodasilvae (collected in a serpentínica outcrop of Alimonde, Bragança), A. simplex (collected in a serpentínica outcrop of Carrazedo, Bragança), Alnus glutinosa as a positive control and A. pintodasilvae grown in laboratory without Ni. The isopods were fed for 32 days under controlled conditions of humidity and temperature. The results showed that A. pintodasilvae induced high mortality of isopods regarding to the other plants species used, primarily A. Pintadasilvae in vitro and Alnus glutinosa. These results indicate that Ni has a toxic effect on isopods scavengers and thus acts as an elemental defense in A. pintodasilvae. The results obtained with A. simplex suggest an anti-herbivory effect somehow identical to A. pintodasilvae, since no significant differences were detected between the effect of this two plant species in the accessed parameters. The results suggest the existence, in A. Simplex, of an anti-herbivory defense mechanism, such as glucosinolates and phenolic compounds, which may not be so effective as Ni hiperacumulação in A. pintodasilvae. .
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24

PINI, FRANCESCO. "Genetic and functional variability in plant associated bacteria." Doctoral thesis, 2010. http://hdl.handle.net/2158/546261.

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"Alyssa Morris Forecast: A Commissioned Work for Oboe and Percussion." Doctoral diss., 2011. http://hdl.handle.net/2286/R.I.8971.

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abstract: The purpose of this project was to commission, perform, and discuss a new work for an instrument pairing not often utilized, oboe and percussion. The composer, Alyssa Morris, was selected in June 2009. Her work, titled Forecast, was completed in October of 2009 and premiered in February of 2010, as part of a program showcasing music for oboe and percussion. Included in this document is a detailed biography of the composer, a description of the four movements of Forecast, performance notes for each movement, a diagram for stage set-up, the full score, the program from the premiere performance with biographies of all the performers involved, and both a live recording and MIDI sound file. The performance notes discuss issues that arose during preparation for the premiere and should help avoid potential pitfalls. TrevCo Music, publisher of the work, graciously allowed inclusion of the full score. This score is solely for use in this document; please visit the publisher's website for purchasing information. The commission and documentation of this composition are intended to add to the repertoire for oboe in an unusual instrument pairing and to encourage further exploration of such combinations.
Dissertation/Thesis
Forecast - Mvt 1: Clouds Descending (LIVE)
Forecast - Mvt 2: Rain Dance (LIVE)
Forecast - Mvt 3: Whirlwind (LIVE)
Forecast - Mvt 4: Tempest and Resolution (LIVE)
Forecast - Mvt 1: Clouds Descending (MIDI)
Forecast - Mvt 2: Rain Dance (MIDI)
Forecast - Mvt 3: Whirlwind (MIDI)
Forecast - Mvt 4: Tempest and Resolution (MIDI)
D.M.A. Music 2011
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26

LIN, JU-YU, and 林洳妤. "An Exploration of Alyssa Morris's Four Personalities for Oboe and Piano." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/h3tc69.

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27

Harley, Alyssa Skye. "Analysis of a nuclear role for 'pebble', a gene required for cytokinesis in Drosophila / by Alyssa Harley." Thesis, 2002. http://hdl.handle.net/2440/21866.

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"May 2002"
Bibliography: leaves 157-176.
x,176 leaves : ill. (some col.), plates (some col.) ; 30 cm.
Through the use of a variety of biochemical and genetic techniques, the importance of the nuclear localisation of PBL was examined, as well as the function of its RadECl and BRCT domains. The RadECl/BRCT domains were found to be required in the cytoplasm for cytokinesis, extending the range of function attributed to these domains. PBL was also shown to shuttle between the nucleus and the cytoplasm, providing an explanation for the observed ability of nuclear PBL to influence cytoplasmic structure.
Thesis (Ph.D.)--University of Adelaide, Dept. of Molecular Biosciences, 2002
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28

Diniz, Gonçalo Trindade Salgueiro Vagos. "A Ficção Especulativa de Alyssa Wong: Uma Proposta de Tradução dos Contos "A Fist of Permutations in Lightning and Wildflowers" e "Hungry Daughters of Starving Mothers"." Master's thesis, 2020. http://hdl.handle.net/10362/115900.

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O presente Trabalho de Projeto tem como objetivo apresentar uma proposta de tradução de dois contos da escritora norte-americana contemporânea Alyssa Wong, sendo estes “A Fist of Permutations in Lightning and Wildflowers” e “Hungry Daughters of Starving Mothers”, à qual se segue um comentário à mencionada proposta de tradução. Para a execução do presente Trabalho de Projeto, começa-se com uma breve contextualização teórica, aborda-se o conceito de “ficção especulativa”, género literário no qual se inserem os contos de Wong, e tecem-se algumas considerações sobre a sua presença no sistema literário português. De seguida, é feita uma descrição sumária da vida e obra da autora, antes da proposta de tradução e do respetivo comentário. Neste último, abordam-se os problemas e dificuldades terminológicos, gramaticais e culturais mais relevantes enfrentados durante o processo de tradução.
This Project aims to present a translation proposal of two short stories by the contemporary American writer Alyssa Wong, “A Fist of Permutations in Lightning and Wildflowers” and “Hungry Daughters of Starving Mothers”, which will be followed by a commentary on the already mentioned translation proposal. For the execution of this Project, a brief contextualization related to Translation Studies is provided, as well as some considerations on the concept “speculative fiction”, the literary genre of Wong’s short stories, and its presence in the Portuguese literary system. A brief description of the author's life and work is also added. The translation proposal and respective commentary follow. In the latter, the most relevant terminological, grammatical and cultural problems and difficulties faced during the translation process are addressed.
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Kluth, Christian. "Zentrale und periphere Populationen von Hornungia petraea: Biodiversität und Demographie auf unterschiedlichen raum-zeitlichen Skalenebenen." Doctoral thesis, 2004. http://hdl.handle.net/11858/00-1735-0000-0006-B699-D.

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