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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Isolamento do cairomônio de Anagasta kuehniella Zeller (Lepidoptera: Pyralidae) responsável pela atração do parasitoide Habrobracon hebetor Say (Hymenoptera: Braconidae) / Kairomone isolation of Anagasta kuehniella Zeller (Lepidoptera: Pyralidae) responsible for its parasitoid attraction Habrobracon hebetor Say (Hymenoptera: Braconidae)

Favaris, Arodí Prado 15 December 2016 (has links)
Cairomônios são semioquímicos envolvidos nas interações interespecíficas dos insetos, que beneficiam o receptor em detrimento do emissor. Uma destas interações envolve a busca hospedeira por parasitoides, que detectam estes compostos como estratégia para localizar seus hospedeiros. No caso do ectoparasitoide larval, Habrobracon hebetor Say (Hymenoptera: Braconidae), o \'frass\' de Anagasta kuehniella Zeller (Lepidoptera: Pyralidae) libera um cairomônio que atrai as fêmeas do parasitoide. Considerando que A. kuehniella é muito utilizada para produção de ovos, visando à criação de inimigos naturais, este cairomônio é indesejável, pois acaba favorecendo altas infestações por H. hebetor, podendo causar prejuízos expressivos ao longo do processo. Uma das soluções para o controle de tais infestações poderia ser o emprego de armadilhas com o semioquímico sintético. Entretanto, como o cairomônio ainda não foi identificado, este trabalho teve como objetivo o seu isolamento - a etapa inicial para sua identificação. O cairomônio foi extraído por meio da lavagem com solvente e aeração do \'frass\' de A. kuehniella. Os extratos foram, então, testados em olfatometria de quatro vias com fêmeas do parasitoide, registrando-se o tempo de permanência em cada tratamento. O extrato de lavagem ativo foi fracionado em coluna de sílica em cinco frações, cuja atratividade também foi averiguada para proceder com o isolamento do cairomônio. Os extratos e frações foram então analisados por cromatografia gasosa por ionização em chama (GC-FID) e espectrometria de massas (GC-MS), a fim de localizar compostos exclusivos nas amostras ativas. Além disso, as frações provenientes do extrato de lavagem foram aeradas para a extração de seus compostos voláteis e também analisadas por GC-MS. O cairomônio foi isolado na fração 75% éter, indicando ser um composto polar. Por comparação dos cromatogramas, apenas um pico na coluna HP-5ms foi selecionado como pertencente ao cairomônio. Em coluna Rtx-1ms, o pico bifurcou-se, indicando que, pelo menos, um dos compostos faz parte do cairomônio. As combinações metodológicas deste trabalho conduziram ao isolamento do cairomônio presente no \'frass\' de A. kuehniella e à seleção de pelo menos um composto que compõe o semioquímico responsável pela atração do parasitoide H. hebetor, resultando nas primeiras informações de sua estrutura química para sua futura identificação. / Kairomones are semiochemicals involved in interspecific interactions of insects that benefit the receiver to the detriment of the emitter. One of these interactions is host searching by parasitoids which detect these compounds as a strategy to locate their hosts. In the case of the larval ectoparasitoid, Habrobracon hebetor Say (Hymenoptera: Braconidae), the \'frass\' of Anagasta kuehniella Zeller (Lepidoptera: Pyralidae) releases a kairomone that attracts females parasitoids. Considering that A. kuehniella has been used for egg production in order to keep natural enemy rearing, this kairomone is undesirable, because it may lead to high H. hebetor infestation and causes important losses during the rearing process. One of the attempts to control these infestations could be the use semiochemical-baited traps. However, as the kairomone is still unidentified, the aim of this work was to isolate it - the first step for its identification. The kairomone was extracted by solvent washing and aeration of A. kuehniella \'frass\'. Then the extracts were tested in a four-way olfactometer with female parasitoids, registering the time taken in each treatment. The active washing extract was fractionated in five fractions in a silica column, and its attractivity was evaluated to proceed to isolation. The extracts and fractions were then analysed by gas chromatography with flame ionization detector (GC-FID) and gas chromatography coupled with mass spectrometry (GC-MS), in order to locate exclusive compounds in active samples. Furthermore, the fractions from the washed extract were aerated to extract their volatile compounds that were also analysed by GC-MS. The kairomone was isolated in the 75% ether fraction, indicating that it is a polar compound. Comparing the chromatograms, only one peak on the HP-5ms column was selected as belonging to the kairomone. On the Rtx-1ms column, the peak bifurcated, indicating that at least one of the compounds is part of the kairomone. The methodological combinations of this work provided the isolation of the kairomone present in A. kuehniella \'frass\' and the selection of at least one compound that comprises the semiochemical that attracts H. hebetor parasitoid, resulting in the first source of information about its chemical structure for its future identification.
2

Isolamento do cairomônio de Anagasta kuehniella Zeller (Lepidoptera: Pyralidae) responsável pela atração do parasitoide Habrobracon hebetor Say (Hymenoptera: Braconidae) / Kairomone isolation of Anagasta kuehniella Zeller (Lepidoptera: Pyralidae) responsible for its parasitoid attraction Habrobracon hebetor Say (Hymenoptera: Braconidae)

Arodí Prado Favaris 15 December 2016 (has links)
Cairomônios são semioquímicos envolvidos nas interações interespecíficas dos insetos, que beneficiam o receptor em detrimento do emissor. Uma destas interações envolve a busca hospedeira por parasitoides, que detectam estes compostos como estratégia para localizar seus hospedeiros. No caso do ectoparasitoide larval, Habrobracon hebetor Say (Hymenoptera: Braconidae), o \'frass\' de Anagasta kuehniella Zeller (Lepidoptera: Pyralidae) libera um cairomônio que atrai as fêmeas do parasitoide. Considerando que A. kuehniella é muito utilizada para produção de ovos, visando à criação de inimigos naturais, este cairomônio é indesejável, pois acaba favorecendo altas infestações por H. hebetor, podendo causar prejuízos expressivos ao longo do processo. Uma das soluções para o controle de tais infestações poderia ser o emprego de armadilhas com o semioquímico sintético. Entretanto, como o cairomônio ainda não foi identificado, este trabalho teve como objetivo o seu isolamento - a etapa inicial para sua identificação. O cairomônio foi extraído por meio da lavagem com solvente e aeração do \'frass\' de A. kuehniella. Os extratos foram, então, testados em olfatometria de quatro vias com fêmeas do parasitoide, registrando-se o tempo de permanência em cada tratamento. O extrato de lavagem ativo foi fracionado em coluna de sílica em cinco frações, cuja atratividade também foi averiguada para proceder com o isolamento do cairomônio. Os extratos e frações foram então analisados por cromatografia gasosa por ionização em chama (GC-FID) e espectrometria de massas (GC-MS), a fim de localizar compostos exclusivos nas amostras ativas. Além disso, as frações provenientes do extrato de lavagem foram aeradas para a extração de seus compostos voláteis e também analisadas por GC-MS. O cairomônio foi isolado na fração 75% éter, indicando ser um composto polar. Por comparação dos cromatogramas, apenas um pico na coluna HP-5ms foi selecionado como pertencente ao cairomônio. Em coluna Rtx-1ms, o pico bifurcou-se, indicando que, pelo menos, um dos compostos faz parte do cairomônio. As combinações metodológicas deste trabalho conduziram ao isolamento do cairomônio presente no \'frass\' de A. kuehniella e à seleção de pelo menos um composto que compõe o semioquímico responsável pela atração do parasitoide H. hebetor, resultando nas primeiras informações de sua estrutura química para sua futura identificação. / Kairomones are semiochemicals involved in interspecific interactions of insects that benefit the receiver to the detriment of the emitter. One of these interactions is host searching by parasitoids which detect these compounds as a strategy to locate their hosts. In the case of the larval ectoparasitoid, Habrobracon hebetor Say (Hymenoptera: Braconidae), the \'frass\' of Anagasta kuehniella Zeller (Lepidoptera: Pyralidae) releases a kairomone that attracts females parasitoids. Considering that A. kuehniella has been used for egg production in order to keep natural enemy rearing, this kairomone is undesirable, because it may lead to high H. hebetor infestation and causes important losses during the rearing process. One of the attempts to control these infestations could be the use semiochemical-baited traps. However, as the kairomone is still unidentified, the aim of this work was to isolate it - the first step for its identification. The kairomone was extracted by solvent washing and aeration of A. kuehniella \'frass\'. Then the extracts were tested in a four-way olfactometer with female parasitoids, registering the time taken in each treatment. The active washing extract was fractionated in five fractions in a silica column, and its attractivity was evaluated to proceed to isolation. The extracts and fractions were then analysed by gas chromatography with flame ionization detector (GC-FID) and gas chromatography coupled with mass spectrometry (GC-MS), in order to locate exclusive compounds in active samples. Furthermore, the fractions from the washed extract were aerated to extract their volatile compounds that were also analysed by GC-MS. The kairomone was isolated in the 75% ether fraction, indicating that it is a polar compound. Comparing the chromatograms, only one peak on the HP-5ms column was selected as belonging to the kairomone. On the Rtx-1ms column, the peak bifurcated, indicating that at least one of the compounds is part of the kairomone. The methodological combinations of this work provided the isolation of the kairomone present in A. kuehniella \'frass\' and the selection of at least one compound that comprises the semiochemical that attracts H. hebetor parasitoid, resulting in the first source of information about its chemical structure for its future identification.
3

Examining black soldier fly (Hermetia illucens) composting for urban ag specialty crop production

Catherine Terrell (12322217) 03 May 2022 (has links)
<p>  </p> <p>Urban farmers face many unique challenges associated with the urban environment in which they produce. One of the most expensive and limited resources is access to healthy soils. There is often low organic matter and industrial contaminants present in urban soils, resulting in the need for remediation, such as capping and importing topsoil and compost. Recently, black soldier fly larvae (<em>Hermetia illucens; BSF)</em> have been recognized as an efficient organism used to break-down organic matter and produce a soil amendment comparable to traditional fertilizers. These fly larvae can feed on a wide range of organic waste (plant material, biosolids, food waste, etc.), can break down contaminants such as pharmaceuticals or pesticides, and impact the bioavailability of heavy metals. The resulting material is a digestate that can be applied as a soil amendment, much like the vermicomposting processes of worms. Fly pupae can be harvested and used as a nutrient dense feedstock for livestock or reared to adults to continue the cycle of composting.  Knowledge gaps remain regarding the impact of feedstock on the nutritional quality of the digestate for crop production and the application and implementation of BSF composting on-farm. We found that larval weight is unaffected by diet streams, however, larval length is improved on food waste streams. Additionally, crop growth varies when grown with BSFL digestate.</p>
4

Assessing insect-based products as feed ingredients for aquaculture

Devic, Emilie D. P. January 2016 (has links)
Research has been actively looking for alternative feed ingredients to reduce the reliance of the aquafeed industry on marine ingredients, namely fish meal (FM) and fish oil (FO). In this context, insects, in particular housefly (Musca domestica) and black soldier fly (BSF, Hermetia illucens) larvae, have been identified as promising candidates. Although a global insect farming industry is emerging, it is for now constrained by regulatory and technical bottlenecks that raise the question ‘where and how insect-based products could be integrated into aquaculture’. The literature indicated a high interspecies variability of the results when replacing FM with insect meals in fish diets and previous work failed to consider the existing challenges related to the insect production to demonstrate commercial relevance and applicability. In this thesis, maggot meals (MM) and frass (insect digestate) were assessed as strategic feed ingredients for two commercially important farmed species: Atlantic salmon, (Salmo salar) and Nile tilapia (Oreochromis niloticus), in their relevant contexts. Case studies showed that both housefly and BSF MM are high quality feed ingredients and suitable alternative to FM. Specifically, dietary inclusions of up to 200 g/kg of crude or defatted housefly larvae meal did not compromised the feed digestibility and utilisation and the growth performance and body composition of salmon parr (freshwater stage), compared to a FM-based control diet. Hormone (17α-methyltestosterone) treated diets containing between 250 and 1000 g/kg BSF or housefly meal were found as effective as a commonly used pure hormone-treated FM in sex-reversal process leading to 99.8 to 100% males, high survival and evenness of the fish produced. In a commercial diet for advanced nursing of Nile tilapia fingerlings, up to 80 g/kg BSF meal was included without impairing the fish performance and body composition; dietary inclusion was limited by the lipid content of the crude MM. Finally, BSF frass derived from brewery spent grains or processed food wastes were found more effective when used as soil bio-fertilisers with minimum application rate of 10.0 tonnes/ha or 5.0 tonnes/ha, respectively (for a spring onion culture), rather than supplemental feeds for tilapia farmed in semi-intensive conditions (fertilised pond). The study also indicated that site-specific conditions should be accounted to support appropriate and sustainable use of insect-based products but in any case, juvenile fish should be strategically targeted given their requirements. It is expected that this approach, could support the sustainable intensification of aquaculture and contribute more broadly to food security whilst contributing to the development of a circular economy.
5

Analýza pracovních technologií při zpracování dřevní suroviny rychle rostoucích topolů a obdobných dřevin pro jejich další využití. / Analysis of technologies for processing wood raw material fast-growing poplar trees and similar trees for further use.

PLEVKA, Vojtěch January 2010 (has links)
The dissertation analyzes the work technology in the processing of fast growing poplar trees and similar trees. In the experimental section were described two different methods of processing the lines of fast-growing poplar trees. It was further verified by the performance and suitability of use Doppstadt AK 450 shredder processing fast-growing poplars and similar trees.
6

Impacts d’amendements organiques sur les capacités phytoremédiatrices de saules et de peupliers

Brunette, Marc Olivier 08 1900 (has links)
Les sites industriels abandonnés présentent souvent des sols ayant des propriétés physico-chimiques atypiques et des concentrations élevées en métaux traces, rendant leur dépollution coûteuse de surcroît quand les superficies sont grandes. Les phytotechnologies, comme la phytoremédiation, émergent alors comme des options économiques et socialement acceptables. Cette étude, conduite en conditions semi-contrôlées, a examiné la capacité de saules (Salix miyabeana 'SX67') et de peupliers (Populus DNxM '915508') à phytoremédier des sols contaminés, notamment par le cuivre, et a comparé leurs performances suivant l’application de frass, un résidu de l’élevage d’insectes, et de fumier de poule, tous deux produits dans une démarche d’économie circulaire. Dans l'ensemble, aucune tendance claire n'a pu être identifiée entre les traitements et les espèces concernant la production de biomasse, les paramètres physiologiques, ou l'assimilation des éléments traces. Cependant, les saules amendés avec du frass ont atteint une hauteur moyenne de 210 cm, significativement supérieure à celle des saules non fertilisés. Les concentrations de cuivre extrait par les plantes n'ont pas été affectées par les deux types d'amendements organiques. Comme pour le cuivre, qui a montré des concentrations de 407 mg kg-1 dans les racines et de 14 mg kg-1 dans les parties aériennes, la majorité des dix éléments étudiés a été principalement retrouvée dans les racines. Seuls le zinc et le cadmium ont montré un facteur de translocation supérieur à un. En ce qui concerne les différentes fractions de cuivre dans le sol, aucune différence significative n'a été observée entre les traitements pour les fractions labiles et phytodisponibles, bien qu'une tendance puisse être notée pour les peupliers amendés avec du fumier. Les macronutriments tels que l'azote et le phosphore ont montré une interaction complexe impliquant les espèces, les amendements, et la contamination en cuivre. Malgré des résultats ambigus et une complexité inattendue, cette étude semble indiquer que le frass et le fumier de poule sont des matériaux efficaces en comparaison des engrais inorganiques communément utilisés. Néanmoins, ils soulignent également la nécessité d'une recherche plus approfondie sur l'utilisation de ces amendements organiques issus de l'économie circulaire afin d'optimiser leur utilisation. Une telle exploration, en alignement avec les principes de durabilité et de recyclage, pourrait éventuellement orienter nos stratégies vers des solutions plus efficaces, viables et économiques, contribuant ainsi à l'avenir de la restauration écologique des terrains industriels abandonnés. / Brownfield sites, characterized by soils with atypical physicochemical properties and high trace element (TE) concentrations, are generally expensive to decontaminate especially when large areas are involved. Economical and socially approved phytotechnologies, such as phytoremediation, offer environmentally conscious solutions that require an approach distinct from those using chemical fertilizers in industrial or agricultural contexts. This study, conducted under semi-controlled conditions, examined the ability of willows (Salix miyabeana 'SX67') and poplars (Populus DNxM '915508') to phytoremediate contaminated soils, especially those contaminated with copper, and compared their performance following the application of frass, a residue from insect breeding, and chicken manure, both produced in a circular economy approach. The study examined biomass production, specific physiological properties, and the assimilation of copper and other trace elements into plant tissues. Results showed no discernible pattern between the treatments and the species. However, willows treated with frass achieved significantly greater heights, averaging 210 cm. Neither organic amendment influenced the level of copper phytoextracted with, in most cases, higher concentrations of trace elements in roots rather than in the aerial parts, exemplified by copper levels of 407 mg kg-1 in roots and only 14 mg kg-1 in leaves. Notably, only zinc and cadmium had translocation factors greater than one. Concerning soil copper fractions, there were no statistical differences in both labile and phytoavailable copper across treatments despite a visible trend for frass-amended poplars. Macronutrients such as nitrogen and phosphorus demonstrated complex interactions dependent on the species, amendments, and Cu contamination. Despite ambiguous results and unexpected complexity, this study seems to indicate that frass and chicken manure are effective materials compared to commonly used inorganic fertilizers. However, they also emphasize the need for more in-depth research on the use of these organic amendments from the circular economy to optimize their utilization. Such exploration, in alignment with principles of sustainability and recycling, could potentially guide our strategies towards more effective, viable, and economical solutions, thereby contributing to the future of ecological restoration of abandoned industrial sites.
7

Problematika stárnutí asfaltových pojiv a směsí / Ageing of asphalt binders and mixtures

Štěpanovský, Vlastimil January 2015 (has links)
Diploma thesis is particularly focused on ageing of asphalt mixtures and asphalt binders. In the theoretical part an array of methods simulating short term and long term ageing consequently is introduced. The main objective of the practical part was to carry out the long-term ageing test method BSA (Braunschweiger Alterung). Thereafter, specimens testing for stiffness properties according to CSN EN 12697-26 were made. After conducting the measurement on those, asphalt binder was extracted and processed to follow-up testing. The testing consisted of a range of methods – Penetration CSN EN 1426, Ring and Ball test CSN EN 1427, Determination of the Frass breaking point CSN EN 12593, Determination of complex shear modulus CSN EN 14770 and Dynamic viscosity using a dynamic shear rheometer (DSR). The given results were assessed in the last part in order to evaluate the rate of the binder degradation caused by the method BSA.

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