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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.
411

Pollination biology of <i>Echinacea angustifolia</i> and <i>E. purpurea</i> (<i>Asteraceae</i>) in Saskatchewan

Wist, Tyler Jonathan 28 October 2005 (has links)
The goals of this research project were to identify the various insects observed to visit inflorescences of Echinacea angustifolia DC, and to rank these visitors according to their importance as pollinators of E. angustifolia in Saskatchewan. Studying nectar and the nectary is essential to understanding the interaction of disc florets with pollinators. Nectar-sugar production by disc florets of E. angustifolia and E. purpurea (L. Moench) was quantified from anthesis to cessation with production per disc floret peaking in the afternoon of the staminate phase (191.7 µg) and at midday of the first day of the pistillate phase (156.6 µg), respectively. Morphology of the disc-like floral nectaries of both Echinacea species was studied, as well as the ultrastructure of the nectary of E. purpurea. Modified stomata on the nectary rim are the most likely exits for nectar, but creases in the epidermis may also participate. The nectary of E. purpurea is vascularized by phloem alone, which occurred adjacent to the epidermis. Companion cells possessed wall ingrowths, and these cells may unload arriving sugar destined for either an apoplastic or symplastic pathway. Lobed nuclei were a key feature of secretory parenchyma cells, as was a predominance of mitochondria, suggesting that energy-requiring eccrine secretion predominates in E. purpurea. E. angustifolia exhibited a generalist pollination system, with pollinating insects belonging to the orders Coleoptera, Diptera, Hymenoptera, and Lepidoptera. The pollination efficiency of visitors was determined by single insect visits to bagged, virgin inflorescences followed by quantifying pollen tubes at the bases of receptive styles and/or calculating the percentage of shrivelled styles. It was determined that bumble bees (Bombus spp.) were efficient pollinators, indicating that they would likely contribute much to the pollination of E. angustifolia. Grasshopper bee flies (Systoechus vulgaris Loew) were plentiful but individually were not efficient pollinators, but taken together, they provided much pollination. Golden blister beetles (Epicauta ferruginea Say) were efficient pollinators but where yellow-petalled flowers occurred, their numbers on E. angustifolia decreased. Honey bees (Apis mellifera L.) were efficient pollinators and were present in low numbers without managed introduction. Pierid (2003) butterflies were regular visitors and efficient pollinators, and likely contributed significantly to E. angustifolia pollination. When introduced, the alfalfa leafcutter bee (Megachile rotundata Fabr.) preferred not to forage on E. angustifolia and as such, these solitary bees were not suitable as managed pollinators. In large agricultural plantings of E. angustifolia, however, native insects may not be capable of providing sufficient pollination for seed production when floral competition occurs.
412

Bees and wasps in agricultural landscapes: effects of dispersal corridors and land-use intensity at multiple spatial scales / Bienen und Wespen in Agrarlandschaften: Effekte von Ausbreitungskorridoren und Landnutzungsintensität auf verschiedenen räumlichen Skalen

Holzschuh, Andrea Alexandra Violetta 03 May 2006 (has links)
No description available.
413

Incidence of Clostridium botulinum Spores in Honey and Infant Food Samples Collected from Vietnam and Germany / Vorkommen von Clostridium-botulinum-Sporen in Honig- und Säuglingsnahrungsproben aus Vietnam und Deutschland

Vu, Thi Lam An 02 November 2006 (has links)
No description available.
414

Mel de abelhas nativas e africanizadas do estado de Alagoas : composição química, segurança microbiológica e atividade terapêutica. / Honey of beens native and africanized state of Alagoas State : chemical composition,security microbiological and activity therapy.

Duarte, Alysson Wagner Fernandes 30 April 2009 (has links)
The rational development of bees is one of the most promising agricultural activities, since it is essentially self-sustaining family and therefore helps to maintain and restore the environment, through their role in pollination, and guarantee income to the producer who employs his family on it. Honey is the main product of this activity, being generated by honey bees - native or Africanized. Its chemical composition is quite varied, depending mainly of floral, entomological and geographical origin. The purpose of this study was to evaluate the quality of honey from different entomologic sources of the State of Alagoas, in the dry season of 2008/09, by physico-chemical and microbiological criteria, and know their likely actions antioxidant and antimicrobial. Thus, 43 samples of honey (14 of Apis mellifera, 22 of M. scutellaris, 3 of M. quadrifasciata, 2 of M. subnitida e 2 of Plebeia sp) were collected from different municipalities of Alagoas. In relation to the physicochemical parameters, it were evaluated the content of reducing carbohydrates, total carbohydrates, sucrose apparent, moisture, electrical conductivity, pH, acidity, content of total protein, concentration of proline, diastase activity and hydroxymethylfurfural. Regarding to the antioxidant activity, it was evaluated in qualitative and quantitative terms of the content of total phenols and flavonoids, capture of the radical 2,2-diphenyl-1-picrilhdrazil (DPPH) and through the antioxidant power of reduction of Fe3 + &#8594; Fe2 + (FRAP method). It was also evaluated the microbiological safety of honeys through the detection of spores of Clostridium sp., and through the profile of various antimicrobial. We used the nonparametric test of Kruskal Wallis to 95% (p <0.05), because the data did not show normal distribution. It was also performed the correlation of Spearman to 95% significance, p <0.05, and 99% significance, p <0.01. With regard to the physico-chemical parameters, only electrical conductivity and sucrose showed no statistically significant difference (p <0.05) among the different species of honey bees. On the antioxidant activity, the honey of A. mellifera showed higher activity than those of natives, except in the case of honey of Plebeia sp, who stood out in a number of parameters compared to the other native bees. It was found also that the honey of native bees showed slight difference in comparizon to the honeys of A. mellifera regarding to its antimicrobial action, and it was not seen this variation on the activity of heat-resistant fungi, which were also much less sensitive than the bacteria to aqueous solutions of honey (25%). Therefore, the antibacterial action is probably due to the synergistic effect of high concentration of H+ ions (low pH), carbohydrates (osmotic potential) and phenolic compounds that bind to glucose forming units of its cell wall, preventing their proper proliferation. / Fundação de Amparo a Pesquisa do Estado de Alagoas / A criação racional de abelhas é uma das atividades agropecuárias mais promissoras, visto que é essencialmente familiar e auto-sustentável, pois auxilia na manutenção e recuperação do meio ambiente através de seu papel na polinização e garante renda ao produtor que emprega nela a sua família. O mel é o principal produto dessa atividade, sendo gerado por abelhas melíferas - nativas ou africanizadas. Sua composição química é bastante variada, dependendo principalmente da origem floral, entomológica e geográfica. O propósito deste trabalho foi avaliar qualidade do mel de diferentes origens entomológicas do Estado de Alagoas, na estação das secas de 2008/09, por meio de parâmetros físico-químicos e microbiológicos, além de conhecer suas prováveis ações antioxidante e antimicrobiana. Para tanto, coletou-se 43 amostras de méis (14 de Apis mellifera, 22 de M. scutellaris, 03 de M. quadrifasciata, 02 de M. subnitida e 02 de Plebeia sp.) em diferentes municípios alagoanos. Em relação aos parâmetros físico-químicos, avaliou-se o conteúdo de glicídios redutores, glicídios totais, sacarose aparente, umidade, condutividade elétrica, pH, acidez, teor de proteínas totais, concentração de prolina, hidroximetilfurfural e atividade diastásica. Em relação à atividade antioxidante avaliou-se quantitativamente e qualitativamente o conteúdo de fenóis e flavonóides totais, captura do radical 2,2-difenil-1- picril-hidrazil (DPPH), além do método de redução do Fe3+ &#8594; Fe2+ (método FRAP). Avaliou-se, ainda, a segurança microbiológica dos méis através da detecção de esporos de Clostridium sp., além do perfil antibacteriano e antifúngico dos diferentes méis. Foi utilizado o teste não paramétrico de Kruskal Wallis a 95 % de probabilidade (p< 0,05), pois os dados não apresentaram distribuição normal, realizando-se, ainda, a correlação de Spearman a 95 % de significância, p<0,05 e 99% de significância, p<0,01. No tocante aos parâmetros físico-químicos, apenas condutividade elétrica e sacarose não apresentaram diferença estatisticamente significativa (p<0,05) entre os méis das distintas espécies de abelhas. Em relação à atividade antioxidante, os méis de A. mellifera apresentaram ação superior do que os das nativas, exceto no caso dos méis de Plebeia sp., que se destacaram em uma série de parâmetros em comparação com o das demais abelhas nativas. Verificouse, ainda, que os méis de abelhas nativas apresentaram maior atividade antimicrobiana em relação aos méis de A. mellifera. Portanto, a ação antibacteriana provavelmente se deve ao efeito sinergístico da alta concentração de íons H+ (baixo pH), glicídios (potencial osmótico) e compostos fenólicos que se ligam às unidades glicídicas formadoras de sua parede celular, inviabilizando sua adequada proliferação.
415

Les Baka du Gabon dans une dynamique de transformations culturelles- Perspectives linguistiques et anthropologiques / The dynamics of cultural change in the Baka society (Gabon)- linguistic and anthropological perspectives.

Paulin, Pascale 06 December 2010 (has links)
Cette thèse propose une analyse approfondie de la dynamique des changements observés au sein d’une communauté de chasseurs-cueilleurs, les Baka du Gabon. Ce groupe se compose de moins de 1000 individus et parle une langue oubanguienne dans un environnement bantuphone. Une comparaison avec les autres langues du même sous-groupe linguistique met en évidence les spécificités du baka et met au jour des affinités entre cette langue et le monzombo. Ces deux groupes ethnolinguistiques semblent avoir entretenu des relations qui s’inscrivent dans une dynamique d’échange de compétences (chasse-cueillette vs pêche-maîtrise du fer). Ce type de complémentarité se retrouve dans les relations entre les Baka et leurs voisins bantu actuels, dont en particulier les Fang, pour ce qui concerne le Gabon.Le mode de vie des Baka demeure, encore aujourd’hui, largement marqué par la mobilité et la forêt. Toutefois, la sédentarisation imposée par voie gouvernementale, la contigüité avec les Fang de même que l’influence croissante de la mondialisation entraînent des transformations par rapport auxquelles les Baka cherchent à se positionner. Ces dernières touchent la langue (système et utilisation) de même que bon nombre de pratiques socioculturelles (habitat, mobilité, alimentation, subsistance, religion, etc.).La thèse s’efforce d’identifier ces transformations, de les décrire et d’en évaluer l’impact en tenant compte de la diversité des situations. Elle comporte, par ailleurs, une réflexion critique des principes de catégorisation fondée sur l’étude de plusieurs domaines lexicaux (faune, flore, maladie). Certains changements peuvent apparaître en surface sans pour autant remettre en cause, de manière fondamentale, leur attachement à la forêt et à certaines valeurs ancestrales. Toutefois, les différentes pressions exogènes (i.a. sédentarisation, mondialisation) et endogènes (i.a. attitude des individus, transmission) qui déterminent alors le degré d’avancement des différentes transformations, ne doivent pas être sous évaluées en tant qu’elles sont une menace pesant sur la langue, la connaissance de la flore et de la faune et certaines pratiques socioculturelles. / This thesis proposes a detailed analysis on the dynamic of change observed among the Baka from Gabon, a hunter-gatherer community. This group is composed of less than 1000 individuals speaking an Ubangian language inside a Bantu environment. By comparing their language with others from the same linguistic sub-group, some singularities from Baka and some resemblance with the Monzombo sub-group can be seen. These two ethnolinguistic groups, Baka and Monzombo groups, seem to have kept close contact based on skill exchanges (hunting/gathering and fishing/iron skills). This interaction is witnessed in the exchanges the Baka population preserves with their current Bantu neighbors, especially with Fang in Gabon.Nowadays, the Baka way of life is still characterized by their mobility and the forest. Nevertheless, due to a non-migratory lifestyle imposed by the State, the proximity with the Fang group and the growing globalization, dramatic changes are inflicted to the Baka community. Changes at which they are trying to adapt. These constraints do not affect only their language (system and use) but also many sociocultural habits such as settlement, mobility, food and means of support or religion.The aim of this thesis is to identify these ongoing transformations, to describe and to evaluate their impact bearing in mind the singularity of many contexts. An argumentative reflection on categorization principles is also proposed on lexical domains such as fauna, flora and diseases. Certain changes could arise without necessarily questioning their bonds to the forest and ancestral values. Nonetheless, both exogenous (globalization and a sedentary life) and endogenous pressures (individual behavior and culture transmission) determining the progress of different transformations should not be under evaluated as being a threat to the language, to the knowledge of the flora and fauna and to certain sociocultural practices.
416

Dynamique spatio-temporelle des ressources et écologie de l'abeille domestique en paysage agricole intensif / Spatio-temporal dynamic of resources and honey-bee ecology in intensive agricultural landscapes

Requier, Fabrice 18 December 2013 (has links)
L'effondrement des populations d'abeilles domestiques, observé à l'échelle mondiale depuis une vingtaine d'années, est particulièrement alarmant, provoquant le déclin de la filière apicole mais également celui d'un pollinisateur essentiel en milieu agricole. La conservation de l'abeille domestique et de l'apiculture en paysage agricole est donc actuellement un enjeu majeur pour de nombreux acteurs. L'intensification de l'agriculture, insufflée par la politique agricole européenne, est désignée comme une cause majeure dans le déclin de la biodiversité, dont les abeilles sauvages. De nombreuses études ont révélé que le manque de ressources florales est une cause majeure de ce déclin généralisé, mais de façon surprenante, cette cause n'est que très peu investiguée à l'heure actuelle pour l'abeille domestique. Plus généralement, l'écologie de l'abeille domestique en paysage agricole est mal connue. A l'interface entre écologie comportementale, évolutive et paysagère, l'objectif général de cette thèse est d'étudier l'influence conjuguée de l'intensification de l'agriculture et de la dynamique spatio-temporelle des ressources florales en paysage agricole sur (i) leur utilisation et (ii) l'histoire de vie des abeilles. L'originalité de cette étude provient de l'envergure spatiale et temporelle des données empiriques collectées à l'aide de vastes dispositifs de suivis tant au niveau individuel qu'au niveau des colonies. Les résultats obtenus confirment l'influence négative de l'intensification de l'agriculture sur l'écologie de l'abeille domestique. En effet, la dynamique des ressources dominées par trois cultures majeures que sont le colza, le tournesol et le maïs, provoque l'apparition d'une déplétion d'approvisionnement en pollen et nectar. Des ressources aujourd'hui marginalement présentes en paysage agricole intensif telles que les zones boisées et les adventices jouent un rôle prépondérant dans le régime alimentaire des abeilles, pouvant contrer l'intensité de cette déplétion d'approvisionnement. Par des mécanismes a priori adaptatifs, les colonies et les individus adaptent leurs comportements et histoire de vie en réponse à la déplétion d'approvisionnement. Cependant, ces mécanismes de compromis d'allocation des ressources ont un coût important et aboutissent à un affaiblissement des colonies, qui se traduit par la mortalité hivernale des colonies d'abeilles domestiques. Cette étude révèle empiriquement l'importance de la dynamique des ressources dans les causes du déclin de l'abeille domestique, et évoque la présence d'une disette alimentaire en céréaliculture intensive. Ces résultats sont discutés dans l'optique de concevoir des mesures de conservation de l'abeille domestique, de l'apiculture et du service de pollinisation en paysage agricole intensif, afin de limiter les stress environnementaux pour les abeilles tels que le manque de ressources florales et l'exposition aux pesticides. / The collapse of honey bee populations, described around the world for twenty years, is particularly alarming because it causes the decline of beekeeping and of an essential pollinator in agricultural habitats. The conservation of honey bees and beekeeping in agricultural landscape is currently a major challenge for many operators. The agricultural intensification, instilled by the (European) Common Agricultural Policy, is considered as a major cause in the decline of biodiversity, including wild bees. Many studies have shown that lack of floral resources is a major cause of this widespread, but surprisingly, this cause of decline is very few investigated actually to honey bees. More generally, the honey bee ecology in agricultural landscapes is poorly understood. At the interface between behavioral, evolutionary and landscape ecology, the overall objective of this PhD thesis was to study the combined influences of agricultural intensification and the spatio-temporal dynamics of floral resources on (i) the use of this resource and (ii) the life history of honey bees. The originality of this study comes from its large spatial and temporal scale as well as its joint approach at individual and colony levels. The results confirm a negative impact of agricultural intensification on the honey bee. Indeed, three major crops i.e. rapeseed, sunflower and maize have created a temporal resource dynamic which causes a strong food supply depletion in pollen and nectar. Some resources more marginally represented in intensive agricultural landscapes such as wood and weeds play an important role in the honey bee diet, being able to restrict the intensity of food supply depletion. By adaptive mechanisms, colonies and individuals adapt their behavior and life history in response to the food supply depletion. However, these trade-off mechanisms in resource allocation have a significant cost and generate a weakening of colonies that increases overwintering mortality of honey bee colonies. This study shows empirically the importance of the resource dynamic in the causes of honey bee decline, and highlights the presence of a food-shortage period in cereal farming systems. These results are discussed so as to build conservation measures on the honey bee, beekeeping and pollination service in intensive agricultural landscapes, in order to limit environmental stress for honey bees such as lack of floral resources and pesticide exposure.
417

Managing strawberry pollination with wild bees and honey bees: Facilitation or competition by mass-flowering resources?

Bänsch, Svenja 05 February 2019 (has links)
No description available.
418

Development of a novel high resolution and high throughput biosensing technology based on a Monolithic High Fundamental Frequency Quartz Crystal Microbalance (MHFF-QCM). Validation in food control

Calero Alcarria, María del Señor 02 May 2022 (has links)
Tesis por compendio / [ES] La sociedad actual demanda un mayor control en la seguridad y calidad de los alimentos que se consumen. Esta preocupación se ve reflejada en los diferentes planes estatales y europeos de investigación científica, los cuales, plantean la necesidad de innovar y desarrollar nuevas técnicas analíticas que cubran los requerimientos actuales. En el presente documento se aborda el problema de la presencia de residuos químicos en la miel. El origen de los mismos se debe, fundamentalmente, a los tramientos veterinarios con los que se tratan enfermedades y parásitos en las abejas, y a los tratamientos agrícolas con los que las abejas se ponen en contacto cuando recolectan el néctar en cultivos próximos a las colmenas. La Agencia Europea de Seguridad Alimentaria (EFSA) confirma esta realidad al notificar numerosas alertas sanitarias en la miel. En los últimos años, los métodos de análisis basados en inmunosensores piezoeléctricos se han posicionado como la base de una técnica de cribado muy prometedora, la cual puede ser empleada como técnica complementaria a las clásicas de cromatografía, gracias a su sencillez, rapidez y bajo coste. La tecnología de resonadores High-Fundamental Frequency Quartz Crystal Microbalance with Dissipation (HFF-QCMD) combina la detección directa en tiempo real, alta sensibilidad y selectividad con un fácil manejo y coste reducido en comparación con otras técnicas. Además, está tecnología permite aumentar el rendimiento del análisis mediante el diseño de arrays de resonadores en un mismo sustrato (Monolithic HFF-QCMD). En este documento se presenta el diseño de un array de 24 sensores HFF-QCMD, junto con un cartucho de micro-fluídica que traza diversos microcanales sobre los diferentes elementos sensores, a los que hace llegar la muestra de miel diluida a analizar. El cartucho actúa también como interfaz para realizar la conexión entre el array de resonadores y el instrumento de caracterización de los mismos. Para obtener el máximo partido del array diseñado, se desarrolla un método de medida robusto y fiable que permite elevar la tasa de adquisición de datos para facilitar la toma de registros eléctricos de un elevado número de resonadores de forma simultánea, e incluso en varios armónicos del modo fundamental de resonancia. La gran sensibilidad de la tecnología HFF-QCMD a los eventos bioquímicos a caracterizar se extiende también a otro tipo eventos externos, como son los cambios de temperatura o presión, lo que es necesario minimizar con el fin de reducir el impacto que estas perturbaciones no deseadas provocan en la estabilidad y fiabilidad de la medida. Con este fin, se desarrolla un algoritmo de procesado de señal basado en la Discrete Transform Wavelet (DTW). Finalmente, todos los desarrollos tecnológicos realizados se validan mediante la implementación de un inmunoensayo para la detección simultánea, en muestras de mieles reales, de residuos químicos de naturaleza química muy diferente, a saber, el fungicida tiabendazol y el antibiótico sulfatiazol. / [CA] La societat actual demanda un major control en la seguretat i qualitat dels aliments que es consumeixen. Aquesta preocupació es veu reflectida en els diferents plans estatals i europeus d'investigació científica, els quals, plantegen la necessitat d'innovar i desenvolupar noves tècniques analítiques que cobrisquen els requeriments actuals. En el present document s'aborda el problema de la presència de residus químics en la mel. L'origen dels mateixos es deu, fonamentalment, als tractaments veterinaris amb els quals es tracten malalties i paràsits en les abelles, i als tractaments agrícoles amb els quals les abelles es posen en contacte quan recol·lecten el nèctar en cultius pròxims als ruscos. L'Agència Europea de Seguretat Alimentària (EFSA) confirma aquesta realitat notificant nombroses alertes sanitàries en la mel. En els últims anys, els mètodes d'anàlisis basades en immunosensors piezoelèctrics s'han posicionat com la base d'una tècnica de garbellat molt prometedora, la qual pot ser emprada com a tècnica complementària a les clàssiques de cromatografia, gràcies a la seua senzillesa, rapidesa i baix cost. La tecnologia de ressonadors High-Fundamental Frequency Quartz Crystal Microbalance with Dissipation (HFF-QCMD) combina la detecció directa en temps real, alta sensibilitat i selectivitat amb un fàcil maneig i cost reduït en comparació amb altres tècniques. A més, està tecnologia permet augmentar el rendiment del anàlisi mitjançant el disseny d'arrays de ressonadors en un mateix substrat (Monolithic HFF-QCMD). En aquest document es presenta el disseny d'un array de 24 sensors HFF-QCMD, juntament amb un cartutx de microfluídica que estableix diversos microcanals sobre els diferents elements sensors, als quals fa arribar la mostra de mel diluïda a analitzar. El cartutx actua també com a interfície per a realitzar la connexió entre l'array de ressonadors i l'instrument de caracterització d'aquests. Per a traure el màxim partit a l'array dissenyat, es desenvolupa un mètode de mesura robust i fiable que permet elevar la taxa d'adquisició de dades per a facilitar la presa de registres elèctrics d'un elevat nombre de ressonadors de manera simultània, i fins i tot en diversos harmònics del mode fonamental de ressonància. La gran sensibilitat de la tecnologia HFF-QCMD als esdeveniments bioquímics a caracteritzar s'estén també a un altre tipus esdeveniments externs, com són els canvis de temperatura o pressió, la qual cosa és necessari minimitzar amb la finalitat de reduir l'impacte que aquestes pertorbacions no desitjades provoquen en l'estabilitat i fiabilitat de la mesura. A aquest efecte, es desenvolupa un algorisme de processament de senyal basat en la Discrete Transform Wavelet (DTW). Finalment, tots els desenvolupaments tecnològics realitzats es validen mitjançant la implementació d'un immunoassaig per a la detecció simultània, en mostres de mel reals, de residus químics de naturalesa química molt diferent, a saber, el fungicida tiabendazol i l'antibiòtic sulfatiazol. / [EN] Currently, society demands greater control over the safety and quality of the food consumed. This concern is reflected in the different states and European plans for scientific research, which establish the necessity to innovate and develop new analytical techniques that meet current requirements. This document addresses the problem of the presence of chemical residues in honey. Its origin is fundamentally due to the veterinary treatments against diseases and parasites in bees, and also to the agricultural treatments with which the bees come into contact when they collect the nectar in crops close to the hives. The European Food Safety Agency (EFSA) confirms this reality by notifying numerous health alerts in honey. In recent years, analysis methods based on piezoelectric immunosensors have been positioned as the basis of a very promising screening technique, which can be used as a complementary technique to the classic chromatography, thanks to its simplicity, speed and low cost. High-Fundamental Frequency Quartz Crystal Microbalance with Dissipation (HFF-QCMD) resonator technology combines direct real-time detection, high sensitivity and selectivity with easy handling and low cost compared to other techniques. In addition, this technology allows increasing the performance of the analysis through the design of resonator arrays on the same substrate (Monolithic HFF-QCMD). This document presents the design of an array of 24 HFF-QCMD sensors, together with a microfluidic cartridge that establish various microchannels on the different sensor elements, to provide them the diluted honey sample to be analyzed. The cartridge also acts as an interface to make the connection between the array of resonators and the characterization instrument. To get the most out of the designed array, a robust and reliable measurement method has been developed that allows increasing the data acquisition rate to facilitate electrical parameters readout from a high number of resonators simultaneously, and even in several harmonics of the fundamental resonance mode. The great sensitivity of the HFF-QCMD technology to the biochemical events to be characterized also is extended to other types of external events, such as changes in temperature or pressure, which must be minimized in order to reduce the impact that these unwanted disturbances cause in the stability and reliability of the measurement. To this end, a signal processing algorithm based on the Discrete Transform Wavelet (DTW) is developed. Finally, all the technological developments carried out are validated through the implementation of an immunoassay for the simultaneous detection, in real honey samples, of chemical residues of very different chemical nature, namely, the fungicide thiabendazole and the antibiotic sulfathiazole. / The authors would also like to thank Jorge Martínez from the Laboratory of High Frequency Circuits (LCAF) of the Universitat Politècnica de València (UPV) for assistance with profilometry, and Manuel Planes, José Luis Moya, Mercedes Tabernero, Alicia Nuez and Joaquin Fayos from the Electron Microscopy Services of the UPV for helping with the AFM, and SEM measurements. M.Calero is the recipient of the doctoral fellowship BES-2017-080246 from the Spanish Ministry of Economy, Industry and Competitiveness (Madrid, Spain). This research was funded by Spanish Ministry of Economy and Competitiveness with FEDER funds (AGL 2016-77702-R) and European Commission Horizon 2020 Programme (Grant Agreement number H2020-FETOPEN-2016-2017/737212-CATCH-U-DNA - Capturing non-Amplified Tumor Circulating DNA with Ultrasound Hydrodynamics) for which the authors are grateful. Román Fernández is with the Center for Research and Innovation in Bioengineering (Ci2B), Universitat Politècnica de València, València, Spain and with Advanced Wave Sensors S.L., Paterna, València, Spain. (e-mail: rfernandez@awsensors.com); Yolanda Jiménez, Antonio Arnau and María Calero are with the Center for Research and Innovation in Bioengineering (Ci2B), Universitat Politècnica de València, València, Spain; Ilya Reiviakine is with Advanced Wave Sensors S.L., Paterna, Valencia, Spain and with the Department of Bioengineering, University of Washington, Seattle, WA, 98150 USA; María Isabel Rocha-Gaso and José Vicente García are with Advanced Wave Sensors S.L., Paterna, València, Spain. / Calero Alcarria, MDS. (2022). Development of a novel high resolution and high throughput biosensing technology based on a Monolithic High Fundamental Frequency Quartz Crystal Microbalance (MHFF-QCM). Validation in food control [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/182652 / TESIS / Compendio
419

Regionální trh vybranými bio komoditami: bio maso / Market of selected organic commodities (organic meat)

LEŠTINOVÁ, Iva January 2014 (has links)
This thesis deals with the organic livestock production in South Bohemian region. The aim of the thesis was to analyze the South Bohemian organic meat production, production of eggs and honey and distribution of the biocommodities. Through the processing of data from the database IAEI and questionnaire survey, conducted at the level of organic farmers farming in the South Bohemian region with a valid certificate for meat production, development and the current market situation of organic meat production were assessed in the South Bohemian region.
420

Off-Host Biology and Ecology of Immature Gulf Coast Ticks (Amblyomma Maculatum Koch) in Mississippi

Portugal, Jose Santos 06 May 2017 (has links)
Little is understood about off-host behavior and ecology of immature Amblyomma maculatum Koch (Gulf Coast tick). A more complete understanding of this tick is essential to protect human and animal health. My research focused on seasonality and distribution of immatures in Mississippi, potential suitability of some insect and human hosts to larvae, and aspects of nymphal questing behavior. A single larva was collected (third off-host collection reported) when sampling A. maculatum habitat using a novel device. Collection of this larva in November expands the stage’s known seasonality and confirmed a prediction concerning seasonality of larval A. maculatum. Low frequency of immatures (8.3%) confirmed that they’re incredibly difficult to collect off-host. Nymphal collections peaked in March, and known seasonality was extended for both nymphs and adults. I examined known records, elucidating seasonality and distribution of A. maculatum in Mississippi. Either multiple generations per year or diapause are responsible for observed bi-modal distribution of immature collections. Additionally, I compiled the most extensive host record of immature A. maculatum in Mississippi and investigated seasonality patterns using USDA plant hardiness zones. I compiled the most complete record of ticks found on arthropods. Amblyomma americanum and A. maculatum were both confirmed to crawl onto arthropods, giving support to occasional, unintentional dispersal by phoresy. There was no conclusive evidence that larval A. maculatum feed on arthropods, however data supported feeding by larval A. americanum. These results have interesting implications regarding evolution of pathogens/endosymbionts. I provided the first evidence that larval A. maculatum can attach to humans. Rickettsia parkeri, a human pathogen transmitted by this species has recently been shown to be capable of transovarial transmission. Therefore, larval A. maculatum may provide another avenue of transmission. I have demonstrated that A. maculatum are difficult to collect off-host in part because they prefer to quest low to the ground. In choice studies, 5-cm-tall stems were most likely to be occupied by nymphs released into an array of stems. Low vapor pressure deficit encouraged questing, while higher VPD and warmer temperature increased questing height. These results may have implications in understanding host-seeking behavior in other tick species as well.

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