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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.
61

Dispersal and mating behaviour of Queensland fruit fly, Bactrocera tryoni(Froggatt) (Diptera: Tephritidae): Implicationsfor population establishment and control.

Weldon, Christopher William January 2005 (has links)
The Queensland fruit fly, Bactrocera tryoni (Froggatt) (Diptera: Tephritidae), a major pest of horticulture in eastern Australia, is a relatively poor coloniser of new habitat. This thesis examines behavioural properties that might limit the ability of B. tryoni to establish new populations. As the potential for B. tryoni to establish an outbreak population may be most directly limited by mechanisms associated with dispersal and mating behaviour, these two factors were the focus of this research project. The relevance of dispersal and mating behaviour for control of outbreak populations was assessed. Dispersal (i) Dispersal patterns of males and females are not different. Dispersal of post-teneral male B. tryoni from a point within an orchard near Richmond, New South Wales, was monitored following temporally replicated releases. Application of sterile insect technique (SIT) requires knowledge of dispersal from a release point so that effective release rates can be determined. In addition, dispersal following introduction to new habitat can lead to low or negative population growth and an Allee effect. In Spring and Autumn, 2001 � 2003, three different strains of B. tryoni were released: (1) wild flies reared from infested fruit collected in the Sydney Basin; (2) a laboratory-reared strain with a colour mutation (white marks); and (3) sterile flies obtained by gamma-irradiation of a mass-reared strain. Dispersal was monitored using a grid of traps baited with the male attractant, cuelure. During the majority of releases, flies were massmarked using a self-marking technique and fluorescent pigment powder to enable identification of recaptured flies. A preliminary study found that fluorescent pigment marks had no effect on adult survival and marks did not fade significantly in the laboratory over a period of five weeks after eclosion. As cuelure repels inseminated sexually mature female B. tryoni, unbaited, coloured flat sticky traps, and black and yellow sticky sphere traps baited with a food lure (protein autolysate solution) were used to supplement traps baited with cuelure. The effectiveness of these two sticky trap types was assessed, and recaptures used to compare patterns of dispersal from a release point by male and female B. tryoni. Fluorescent yellow (chartreuse), green, and clear unbaited flat sticky traps were relatively ineffective for monitoring dispersal of sterile male and female B. tryoni, recapturing only 0.1% of released sterile flies. Monitoring dispersal with sticky ball traps baited with protein autolysate solution was more successful, with yellow spheres and black spheres recapturing 1.7% and 1.5%, respectively. Trap colour had no effect on recaptures on flat sticky traps or sticky spheres. Equal recapture rates on yellow and black sticky sphere traps suggests that the odour of yeast autolysate solution was more important than colour for attraction of post-teneral flies to traps. Using the results of recaptures on odoriferous black and yellow sticky sphere traps within one week of release, regression equations of male and female recaptures per trap were found to be similar (Figure 4-3). This is the first study to clearly indicate that post-teneral dispersal patterns of male and female B. tryoni released from a point do not differ, enabling the use of existing models to predict density of both sexes of B. tryoni following post-teneral dispersal. (ii) Males disperse further in Spring than in Autumn, but this is not temperature-related. Analysis of replicated recaptures in traps baited with cuelure revealed that dispersal of male B. tryoni in an orchard near Richmond, New South Wales, was higher in Spring than in Autumn (Figure 5-6). As the maximum daily temperature was significantly higher in Spring than in Autumn this result was unexpected, since earlier studies have found that B. tryoni disperse at the onset of cool weather in search of sheltered over-wintering sites. Dispersal of post-teneral B. tryoni may have been affected by habitat suitability; it was found that seasonal trends in dispersal could have been influenced by local habitat variables. Low mean dispersal distances in Autumn may be explained by the presence of fruiting hosts in the orchard, or the availability of resources required by over-wintering flies. There was no significant correlation between temperature and mean dispersal distance, suggesting that higher rates of dispersal cannot be explained by temperature-related increases in activity. Recapture rate per trap was significantly negatively correlated with increasing daily maximum and average temperature. This may have consequences for detection of B. tryoni outbreaks in quarantine areas due to reduced cuelure trap efficiency. (iii) Maturity and source variation affect dispersal and response to cuelure. This research indicated that most male and female B. tryoni do not disperse far from a release point, suggesting that an invading propagule would not spread far in the first generation. However, there is considerable variation in flight capability among individuals. Comparison of wild, laboratory-reared white marks, and gamma-irradiated sterile male B. tryoni indicated that mean dispersal distance and redistribution patterns were not significantly affected by fly origin. Despite no difference in dispersal distance from the release point, recaptures of wild and sterile males per Lynfield trap baited with cuelure were highest within one week after release, whereas recaptures of white marks males per trap increased in the second week. This result may offer evidence to support the hypothesis that sterile male B. tryoni respond to cuelure at an earlier age. Rearing conditions used to produce large quantities of males for sterilisation by gamma-irradiation may select for earlier sexual maturity. Mating Behaviour (i) Density and sex ratio do not affect mating, except at low densities. Demographic stochasticity in the form of sex ratio fluctuations at low population density can lead to an observed Allee effect. The effect of local group density and sex ratio on mating behaviour and male mating success of a laboratory-adapted strain of B. tryoni was examined in laboratory cages. In the laboratory-adapted strain of B. tryoni used in this study, a group of one female and one male was sufficient for a good chance of mating success. The proportion of females mated and male mating success was not significantly affected by density or sex ratio, although variability in male mating success was higher at low density. This could indicate that mating success of B. tryoni can be reduced when local group density is low owing to decreased frequency in encounters between males and females. (ii) Mass-reared males exhibit aberrant mating behaviour, but this does not reduce mating success. Strong artificial selection in mass-rearing facilities may lead to decreased competitiveness of sterile males released in SIT programs as a result of alteration or loss of ecological and behavioural traits required in the field. The effects of domestication and irradiation on the mating behaviour of males of B. tryoni were investigated by caging wild, mass-reared and sterile (mass-reared and gammairradiated) males with wild females. Mating behaviour of mass-reared males was different from that of wild males, but behaviour of wild and sterile males was similar. Mass-reared males were found to engage in mounting of other males much more frequently than wild and sterile males, and began calling significantly earlier before darkness. Male calling did not appear to be associated with female choice of mating partners, although this does not exclude the possibility that calling is a cue used by females to discriminate between mating partners. Conditions used to domesticate and rear large quantities of B. tryoni for SIT may select for an alternative male mating strategy, with mass-reared males calling earlier and exercising less discrimination between potential mating partners. Despite differences in behaviour of wild, mass-reared and sterile males, frequency of successful copulations and mating success were similar. (iii) Pheromone-calling by males was increased in larger aggregations but this did not result in significantly more female visits. Finally, large laboratory cages with artificial leks were used to investigate the importance in B. tryoni of male group size for female visitation at lek sites and initiation of male pheromone-calling. Calling propensity of male B. tryoni was increased by the presence of conspecific males. Females visited the largest lek more frequently than single males, but there was no correlation between lek size and female visitation. Female B. tryoni had a limited capacity to perceive a difference between the number of calling males; female visitation at leks was only weakly associated with male calling, suggesting that lek size and the number of pheromone-calling males may not be the only factor important in locating mates in B. tryoni. The weak, but positive correlation between male calling and female visitation may indicate that passive attraction maintains lek-mating in B. tryoni. Further studies are essential on mating behaviour of B. tryoni, including identification of male mating aggregations in the field, measurement of habitat variables associated with male aggregations, the influence of density on wild B. tryoni mating success, and the role of pheromone-calling, in order to optimise use of SIT for control of this pest.
62

Recherche d'un neutrino stérile avec l'expérience STEREO : construction du veto à muons et estimation du bruit de fond corrélé / Search for a sterile neutrino with the STEREO experiment : construction of a muon veto and estimation of the correlated background

Zsoldos, Stephane 30 September 2016 (has links)
La réévaluation théorique du flux d'antineutrinos émis par les réacteurs nucléaires a révélé un déficit de 6% entre le flux observé et le flux attendu. Cette anomalie des antineutrinos de réacteur est significative à 2.7 σ, et une possible interprétation de ce résultat est l'existence d'un état stérile léger du neutrino vers lequel les neutrinos pourraient osciller à très courte distance. Le projet STEREO présenté dans ce manuscrit a pour objectif de prouver ou d'infirmer l'existence d'une telle oscillation.L'expérience est installée près (~10 m) du cœur compact du réacteur de recherche de l'Institut Laue-Langevin (ILL) à Grenoble, France, qui produit un important flux d'antineutrinos électroniques avec une énergie comprise entre 1 et 10 MeV. Le volume utile du détecteur STEREO consiste en une structure de 2 m3 segmentée en six cellules identiques remplies de scintillateur liquide dopé au gadolinium et alignées dans la direction du cœur. La détection s'effectue à l'aide de la réaction beta-inverse.Cette configuration offre une excellente sensibilité à une éventuelle oscillation à courte distance en mesurant la distorsion relative du spectre des antineutrinos dans chaque cellule en fonction de l'énergie et de la distance.Les lignes expérimentales de faisceaux de neutrons de l'ILL produisent un fort bruit de fond qui a été caractérisé à l'occasion de plusieurs campagnes de mesure. Leur analyse a permis de valider le design des lourds blindages passifs installés autour du détecteur et de la zone d'installation pour modérer leurs effets sur l’expérience STEREO.De plus, un détecteur supplémentaire est installé au-dessus de STEREO pour signaler la présence d'un muon issu du rayonnement cosmique et définir un veto aux mesures physiques. Ces muons, lors de leur passage à travers les blindages du détecteur, peuvent produire des neutrons rapides capables d’imiter le signal attendu par les antineutrinos. Il est donc essentiel de définir un veto qui soit le plus efficace et homogène possible.Il prend la forme d'une cuve de 2.5 m3 remplie d'eau dont la détection est basée sur l’effet Tcherenkov. Cette lumière émise par le passage des muons est récoltée sur 20 tubes photomultiplicateurs répartis au-dessus de la cuve et un additif est rajouté dans l'eau pour améliorer la collection de lumière sur les photomultiplicateurs.Ce veto à muons couvre complètement le détecteur STEREO ainsi que ces blindagesL'étude de plusieurs configurations de ce veto à muons sous la forme de prototypes avant la construction de l'instrument final a permis de définir une méthode de déclenchement du signal pour les muons extrêmement efficace tout en conservant une sensibilité réduite aux autres particules. Ces nombreux tests ont par ailleurs permis la validation et l'optimisation de l'électronique développée pour l'expérience au LPSC qui est la même pour le détecteur STEREO et pour le veto à muons.Après avoir caractérisé le flux de muons sur place et l'efficacité du veto à muons, une simulation a été développée et a permis d'évaluer le nombre de faux événements dus à ces neutrons. Ainsi, ce résultat a confirmé les prérequis scientifiques de l'expérience, à savoir la capacité à sonder l'anomalie des antineutrinos de réacteur en 300 jours de données réacteur.Le détecteur est actuellement en place sur site et prévoit de livrer ses premiers résultats fin 2016. / The re-evaluation of the theoretical antineutrino flux emitted by nuclear reactors revealed a deficit of about 6% between the observed flux and the expected one. This so-called reactor antineutrino anomaly has a statistical significance of 2.7σ, and one possible explanation to this deficit could be the existence of a light sterile neutrino state into which reactor antineutrino oscillate at very short distances. The STEREO project, which will be presented in this thesis, aims to find an evidence of such oscillation.The measurement will take place at only few meters (~10 m) from the compact core of the Institut Laue-Langevin (ILL) research reactor in Grenoble, France, which provides a large flux of electron antineutrinos with an energy range from 1 to 10 MeV. The sensitive volume of the STEREO detector is 2m3 of organic liquid scintillator doped with Gadolinium, consisting of 6 cells stacked along the direction of the core and detecting anti-neutrinos via inverse beta decay.This setup will provide excellent sensitivity to short-baseline oscillations effects by precisely measuring any relative distortion of the antineutrino spectrum as a function of both energy and baseline.Close proximity to the reactor yield a high background environment from nearby experiments that is managed through heavy shielding surrounding the detector. Many measurements campaign has been performed to characterized this background and had allowed the improvement of the passive shielding design installed on-site.Moreover, an additional detector is settled above STEREO to tag the presence of an incoming cosmic muon and define a muon veto. These muons will produce fast neutrons during their interaction through the shieldings of STEREO and these neutrons can mimick the expected antineutrino signal. Therefore it is crucial to define the most efficient and homogenous veto to these muons.It consists of a tank of 2.5m3 of water detecting muons by their Cerenkov radiation. The light emitted is collected thanks to 20 photomultipliers positionned at the top of the tank and a chemical compound is added into the water to improve the light collection on the photomultipliers.This muon veto fully covers the STEREO detector along with its shieldings.Several configurations of the muon veto system using prototypes before the final instrumental has allowed to define a trigger system which allows an excellent efficiency to cosmic muons regarding a little sensitivity to others particles. These numerous tests were also used to check and optimize the dedicated electronics builded at LPSC, which is the same for both the STEREO detector and muon veto.After characterization of the muon flux on site and with respect to the muon veto efficiency, a simulation has been developped to evaluate the rate of fake antineutrino event expected from the muon-induced fast neutrons. Thus, this result has confirmed the scientific requirements of the experience, which is the ability to probe the reactor antineutrino anomaly in 300 days of reactor data.STEREO is at the moment being comissionned and will deliver his first results at the end of 2016.
63

Recherche de neutrino stérile par l'expérience STEREO : optimisation du blindage et calibration de l'échelle d'énergie / Search for a sterile neutrino with the STEREO experiment : shielding optimisation and energy calibration

Kandzia, Felix 11 December 2017 (has links)
La recherche de neutrinos stériles et légers est, à l’heure actuelle, l’un des enjeux majeurs de laphysique des neutrinos. Une indication de leur existence résulte de l’anomalie des antineutrinosde réacteur, qui découle du déficit de 6% entre les taux prédits et les taux observéspar les expériences à courte distance de réacteurs. Ce déficit peut être interprété comme uneoscillation à courte distance des neutrinos. L’objectif de l’expérience STEREO, situé auprès duréacteur de recherche de l’Institut Laue Langevin (ILL), à Grenoble, France, est d’étudier cetteoscillation. La cible du détecteur de neutrinos est placée entre 8,9 et 11,1m du coeur compactdu réacteur d’ILL. Le détecteur consiste d’environ 2t d’un scintillateur liquide, dopé avec duGd. Le volume actif est séparé dans le sens de la longueur en six cellules. Les antineutrinos sontdétectés par la désintégration bêta inverse, où ils interagissent avec un proton libre (ion H+) etproduisent un positron et un neutron. Les deux particules sont détectées dans le scintillateurpar une coïncidence retardée où le positron crée un signal prompt et le neutron est capturéaprès un temps de modération. La lumière produite par le scintillateur est mesurée par lesphotomultiplicateurs (PM). Le détecteur est complété par un“gamma catcher” qui entoure la cible et par un veto à muons.Ce manuscrit présente des études concernant la préparation et la mise en exploitation del’expérience STEREO. La conception du blindage magnétique des PM a été menée sur la basede simulations par éléments finis afin d’examiner différentes options, d’étudier en détail lesperformances de l’option retenue ainsi que de déterminer la qualité nécessaire des matériauxutilisés. Sur la base de ces études, la collaboration a retenu un plan de blindage en deuxcouches: une couche de fer doux à l’extérieur, couvrant le détecteur et le veto à muons, et unecouche de mu-métal autour de la cible. Ce blindage réduit les champs magnétiques externes à laposition des PM de la cible à moins de 60μT pour toutes les configurations connues de champsexternes. Ceci réduit à moins de 2% une variation de l’amplification des PM induite par deschangements des champs magnétiques.D’autre part, des études du bruit de fond sur le site de STEREO ont été menées. Unecartographie du bruit de fond du rayonnement gamma a été effectuée avec des détecteurs augermanium et un scintillateur NaI, afin de valider l’efficacité du blindage installé. Uneestimation du taux de bruit de fond est présentée et comparée au taux mesuré avec STEREO.Dans l’état actuel de l’analyse des données, le bruit de fond de coïncidences fortuites est inférieurau bruit de fond corrélé induit par les muons cosmiques. Après une première phase d’exploitationde STEREO, un “doigt de gant” en fin de vie situé à l’avant de STEREO a dû être retiré.Un bouchon était adapté à l’extrémité de ce doigt de gant afin de réduire le bruit du fondpour STEREO. Ce dispositif n’ayant pas pu être réinstallé à la suite l’enlèvement du doigt degant, un nouveau blindage a été proposé par l’ILL. Une série des simulations neutroniques etphotoniques (MCNP) a été effectué pour étudier l’effet de ce changement sur le bruit de fondautour de STEREO et pour décider si le blindage proposé était suffisant. Les deux scénariosavant et après l’enlèvement ont été comparés et selon cette simulation, la situation du bruit defond devrait être améliorée.Enfin une procédure a été proposée et appliquée pour analyser les données de calibration del’échelle d’énergie de STEREO. La procédure a été élaborée pour être applicable pour toutes lessources de calibration disponibles et pour minimiser les incertitudes systématiques. Le résultatpeut être utilisé pour ajuster les paramètres de la simulation Geant4 du détecteur développée parla collaboration, par comparaison avec des données mesurées et après pour déterminer l’échellede l’énergie avec la précision requise de < 2%. / Light sterile neutrinos are currently a topic actively discussed in neutrino physics. Oneindication of their possible existence and their participation in neutrino oscillations is the ReactorAntineutrino Anomaly, which states a deficit of about 6% between predicted and observedantineutrino fluxes in short baseline reactor neutrino experiments. The STEREO experimentaddresses this anomaly by searching for neutrino oscillations at baselines of 8.9-11.1m from thecompact core of the research reactor of the Institut Laue Langevin (ILL), Grenoble, France. Forthis purpose a Gd-loaded liquid scintillator detector was designed with an active target massof about 2 t. The target volume is subdivided in six optically separated cells along the line ofpropagation of the neutrinos. The electron antineutrinos emitted from the reactor are detectedvia the inverse beta decay on hydrogen nuclei, where a positron and a neutron are created. Thesetwo particles are detected in the scintillator in delayed coincidence, with the prompt signal fromthe positron and a delayed signal from neutron capture. The scintillation light created in theprocesses is read out by photomultiplier tubes (PMTs) on top of the detector cells. The detectoris completed by a gamma catcher and a muon veto.This manuscript covers parts of the preparation and the commissioning of the STEREOexperiment. As basis for the design process of the magnetic shielding for STEREO’s PMTsa series of finite element simulations was performed. The studies of different general layoutsand required material qualities as well as of details of the final design are summarised. Underconsideration of these studies the collaboration opted for a shielding design, a double layer setupwith an outer soft iron and inner mumetal layer, which has the required shielding efficiency toreduce the magnetic field at the position of the detector PMTs below 60 μT for all known externalmagnetic field configurations. This limits the maximum PMT gain change due to variations ofthe external magnetic fields to < 2%.Furthermore different studies have been performed concerning the on-site background situation.A mapping of the-ray background was conducted with high purity germanium detectorsand a NaI scintillator detector, in order to validate the efficiency of the installed shielding. Thefocus lied on the characterisation of the count rate in the neutron capture energy window. Anestimation of the background rate is presented and compared to the rate obtained in STEREO.At the current state of the analysis the background of accidental coincidences in STEREO is aminor contribution compared to the muon induced correlated background. In addition a seriesof MCNP simulations was performed to determine the impact of a beamtube removal in thevicinity of STEREO on the overall reactor-related background situation. The beamtube wasclosed by a dedicated shielding, optimised for background reduction for STEREO, which couldnot be reinstalled after removal of the tube. A new shielding at the end of the former beamtubewas proposed by the ILL. Its shielding effect was studied with MCNP and compared tothe previous configuration in order to assess whether the new shielding suffices or needs to beimproved. According to these simulations the background situation is expected to improve.Finally a procedure is proposed and applied for the analysis of the energy calibration ofthe STEREO detector. The procedure is designed to be applicable to all available calibrationsources and to minimise systematic uncertainties. It can be used to adjust parameters in theexisting Geant4-based simulation of the detector, developed by the collaboration, by comparisonto measured data and later to determine the energy scale with the required precision of < 2%.
64

Análise técnica da substituição parcial e total do agregado graúdo por estéril escalpado de mineração destinado a fabricação de concreto / Technical analysis of the partial and total replacement of the grass aggregate by sterile mining for the manufacture of concrete

Lopes, Diego Faleiros 27 June 2018 (has links)
Submitted by Ana Caroline Costa (ana_caroline212@hotmail.com) on 2018-11-30T19:42:24Z No. of bitstreams: 2 Dissertação - Diego Faleiros Lopes - 2018.pdf: 15702568 bytes, checksum: 1e255d577ff34d84d1e9b5da95955fbc (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2018-12-03T13:19:06Z (GMT) No. of bitstreams: 2 Dissertação - Diego Faleiros Lopes - 2018.pdf: 15702568 bytes, checksum: 1e255d577ff34d84d1e9b5da95955fbc (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-12-03T13:19:06Z (GMT). No. of bitstreams: 2 Dissertação - Diego Faleiros Lopes - 2018.pdf: 15702568 bytes, checksum: 1e255d577ff34d84d1e9b5da95955fbc (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-06-27 / Fundação de Amparo à Pesquisa do Estado de Goiás - FAPEG / Although construction in Brazil faces an economic recession since 2014, there is still a high demand for raw materials for construction, such as gravel and sand. The price of materials has increased in recent years, especially when basic products are used for the agriculture industry, since 70 to 80% of the volume of concrete is composed of aggregates of gravel and sand. In 2014, 740 million tons of gravel and sand were consumed in Brazil in construction, while in 2015 the consumption was reduced by 519 million tons. To achieve sustainability it is very important to adopt innovative raw materials, with high quality, low price and environmental impact in your production chain. Mining, in its process of mineral processing, is responsible for generating large quantities of waste without utility and economic value, are highly productive and cause environmental impacts. CMOC International, located in southeastern Goiás, is responsible for producing an approximate volume of 2800 t / day of scalp sterile, excavated materials, generated by the activities of extraction (or tilling) without undercutting of the mine. Thus, the objective was to conduct characterization tests, according to ABNT NBR 7211/2009 of the scaled sterile material of the niobium ore processing industry, and of the aggregate by sterile scalpel and to search for new replacement paths for materials in the production of concrete, with this the amount of environmental resources and the commercialization of a new product through an economic analysis. The classes were classified by means of different types of concrete data molding during the abatement phase, 25, 50, 75 and 100% substitution for the evaluation of productivity, compression and traction, immersion absorption, voids index, mass specific, alkali-aggregate verification. The concretes obtained promising results in the tests, reaching them with the intention, because the material presented characteristics. / Embora a construção civil no Brasil enfrente uma rigorosa recessão econômica desde 2014, ainda há alta demanda por matérias-primas para a fabricação de concreto, como brita e areia. O preço destes materiais tem aumentado nos últimos anos, principalmente porque são considerados produtos básicos para a indústria da construção, uma vez que 70 a 80% do volume de concreto é composto por agregados brita e areia. Em 2014, 740 milhões de toneladas de cascalho e areia foram consumidas no Brasil em construção civil, enquanto em 2015 o consumo foi reduzido em 519 milhões de toneladas. Para alcançar a sustentabilidade é importante adotar matérias-primas inovadoras, com alta qualidade, baixo preço e reduzir impactos ambientais em sua cadeia produtiva. A mineração, no seu processo de beneficiamento mineral, é responsável por gerar grandes quantidades de resíduos sem utilidade e sem valor econômico, causando, muitas vezes, impactos ambientais. A CMOC International, situada no sudeste goiano, é responsável por produzir um volume aproximado de 2800 t/dia de estéril escalpado, materiais escavados, gerados pelas atividades de extração (ou lavra) no decapeamento da mina. Sendo assim, o objetivo foi realizar testes de caracterização, de acordo com a ABNT NBR 7211/2009 do material estéril escalpado, proveniente da usina de processamento de minério de nióbio, assim pôde-se estudar o desempenho mecânico e estatístico de concretos moldados com substituição parcial e total de agregado graúdo por estéril escalpado e buscar novos caminhos de aproveitamento de resíduos em substituição de matérias-primas utilizadas na fabricação de concreto. Com isso, tem-se a diminuição de passivos ambientais, incentivando a comercialização de um novo produto através de uma análise econômica. As amostras foram classificadas por meios de ensaios de caracterização físicas e químicas, segundo a agência reguladora brasileira ABNT, para em seguida realizar a moldagem de concretos nas proporções de 0, 25, 50, 75 e 100% de substituição para a avaliação da trabalhabilidade, resistência mecânica à compressão e tração, absorção por imersão, índice de vazios, massa específica, reação álcali-agregado. Os concretos obtiveram resultados promissores nos testes, alcançando o objetivo proposto nesta pesquisa, pois o material apresentou características de um agregado graúdo e resultados favoráveis no concreto tanto no seu estado fresco como endurecido.
65

Avaliação in vitro da citotoxicidade de instrumentos cirúrgicos enxaguados com diferentes qualidades de água. / Assessment of in vitro cytotoxicity of surgical instruments rinsed with different qualities of water

Rafael Queiroz de Souza 16 July 2014 (has links)
Introdução: O Centro de Material e Esterilização (CME) deve garantir a remoção completa de resíduos orgânicos e inorgânicos, sobretudo detergentes e endotoxinas, dos produtos críticos para saúde por meio do enxágue suficiente com água de qualidade. Com base nos recentes relatos de síndromes tóxicas do segmento anterior ocular, que foram associadas às más práticas de processamento do instrumental de oftalmologia, especialmente, a qualidade da água utilizada em seu enxágue final, esta Tese teceu a hipótese de que quanto mais pura for a qualidade da água do último enxágue, menor será a citotoxicidade encontrada nos produtos para saúde. Objetivo: Avaliar a citotoxicidade de cânulas de hidrodissecção submetidas à contaminação desafio, limpeza automatizada com enxágue final em diferentes qualidades de água: de torneira, tratada por deionizador, por destilação, por osmose reversa e por ultrapurificação. Métodos: 130 cânulas de hidrodissecção foram usadas, 26 por grupo experimental, caracterizados, de acordo com a água utilizada no último enxágue. As amostras foram submetidas à contaminação desafio interna e externamente por uma solução contendo 20% sangue de carneiro desfibrinado e 80% de Cloreto de Sódio a 0,9%, para simular um cenário desafiador de sujidade no material cirúrgico oftalmológico, sendo em seguida processadas, de acordo com um procedimento operacional padrão validado para este tipo de cânula, variando-se apenas a qualidade de água no enxágue final. Como controle positivo, foram utilizadas três cânulas descartáveis, que foram submetidas ao mesmo procedimento de contaminação desafio, imersas em uma solução contendo água de torneira e detergente enzimático que, após a evaporação da solução, foram esterilizadas. Para o controle negativo, foram usadas três cânulas das mesmas utilizadas nos grupos experimentais, com o mínimo de manipulação e na forma como foram fornecidas pelo fabricante, tendo sido apenas esterilizadas. Adicionalmente, foi incluído um grupo comparativo, no qual três amostras foram processadas em condições idênticas às dos grupos experimentais, enxaguadas com água de torneira, porém, sem secagem. Sequencialmente, procedeu-se a realização do teste de citotoxicidade pela incorporação do corante vital vermelho neutro para a obtenção da média da viabilidade celular de cada grupo experimental. Resultados: Ausência de citotoxicidade nos extratos das amostras, independente da diluição considerada na análise, sendo 83% a porcentagem média de viabilidade celular mínima obtida no extrato das amostras enxaguadas com água tratada por destilação na diluição de 12,5%. Conclusão: As cânulas de hidrodissecção não demonstraram citotoxicidade, independentemente da qualidade de água utilizada no último enxágue. Os resultados apresentados puderam ser alcançados unicamente por meio do uso de um procedimento operacional padrão de limpeza validado, baseado em literatura científica, em recomendações oficiais e na legislação relacionada. / Introduction: The Central Sterile Supply Department (CSSD) must guarantee the complete removal of organic and inorganic waste, especially detergents and endotoxins, from critical medical devices through sufficient rinsing with good-quality water. Based on recent reports of toxic anterior segment syndromes, which were associated with poor processing practices of ophthalmology instruments, particularly the quality of water used in the final rinse, this thesis has raised the hypothesis that the better the quality of the water used in the last rinse, the lower the cytotoxicity found in medical devices. Objective: To evaluate the cytotoxicity of hydrodissection cannulas, that were submitted to contamination challenge and then automated cleaning with final rinse in different qualities of water: tap water, water treated by a deionizer device, by distillation, by reverse osmosis and by ultrapurification. Methods: 130 hydrodissection cannulas were used, 26 per experimental group, characterized according to the last rinse water used. The samples were submitted to internal and external contamination challenge using a solution containing 20% defibrinated sheep blood and 80% Sodium Chloride at 0.9%, to simulate a challenging scenario of soiled ophthalmic surgical material, which was then processed, according to a validated standard operating procedure for this type of cannula, changing only the quality of water at the final rinse. Three disposable cannulas were used as positive controls, being submitted to the same contamination challenge procedure, then immersed in a solution containing tap water and enzymatic detergent, and then sterilized after evaporation of the solution. Three cannulas, identical to those used in the experimental groups, were used as negative controls, after minimum handling and exactly as they were supplied by the manufacturer, having only been sterilized. Additionally, a comparison group was included, from which three samples were processed under conditions identical to the experimental groups, rinsed with tap water, but without drying. Sequentially, the cytotoxicity assay was performed by incorporating the neutral red vital dye to obtain mean cell viability from each experimental group. Results: We observed absence of cytotoxicity in the sample extracts, regardless of the dilution considered in the analysis, with 83% of minimal cell viability obtained in the sample extract rinsed with distilled water at 12.5% dilution. Conclusion: Hydrodissection cannulas showed no cytotoxicity, regardless of the quality of water used in the final rinse. The results shown here were achieved by using a validated cleaning standard operating procedure based on scientific literature, official recommendations and related legislation.
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O eixo LTB4/MYD88 na inflamação estéril e na sepse em modelos experimentais de diabetes. / The LTB4/MyD88 axis in sterile inflammation and sepsis in experimental models of diabetes.

Luciano Filgueiras Ribeiro Junior 18 August 2014 (has links)
A diabetes tipo 1 (DT1) está associada `a inflamação estéril (IE) e maior susceptibilidade a sepse. A sepse induz a síndrome da resposta inflamatória sistêmica (SIRS) e a inflamação pulmonar aguda (ALI). O leucotrieno (LT) B4 produzido condições inflamatórias induz a expressão de MyD88 em macrófagos (MA). Hipotetizamos que a DT1 induz a síntese de LTB4 promovendo a IE e isto contribui para SIRS, susceptibilidade a sepse e ALI. Os diabéticos apresentaram níveis elevados de LTB4 e IL-1b no soro e seu MA expressaram mais MyD88/STAT-1. A expressão de STAT-1 foi induzida por c-Jun de forma dependente de LTB4. O tratamento com insulina restaurou os níveis de LTB4 e STAT-1/MyD88 e a inibição de LTB4 restaurou os níveis de MyD88 e IL-1b. Na sepse, a inibição de 5LO prolongou a sobrevida dos diabéticos e diminuiu a SIRS menos IL-1b e IL-10 no soro e TNF-a e IL-1b na cavidade peritoneal. O pulmão dos diabéticos apresentaram ALI menos intensa que se correlacionou com um altos níveis de SOCS-1, baixos níveis de MyD88 e falha na ativação de NFkB nos macrófagos alveolares. / Type 1 diabetes (T1D) is associated with sterile inflammation (SI) and increased sepsis susceptibility. Sepsis induces Systemic Inflammatory Response Syndrome (SIRS) and Acute Lung Injury (ALI). Leukotriene (LT) B4 is produced in inflammatory conditions and induces MyD88 expression in macrophages (MA). We hypothesized that T1D induce LB4 that promotes SI contributing to SIRS, sepsis susceptibility and ALI. Diabetics presented higher levels of LTB4 and e IL-1b in the serum and MA expressed more MyD88/STAT-1. STAT-1 expression was induced by c-Jun on LTB4 dependent manner. Insulin treatment restored LTB4 and STAT-1/MyD88 levels and inhibition of LTB4 restored MyD88 and IL-1b levels. During sepsis, 5LO inhibition increased diabetics survival and inhibited SIRS- lower levels of IL-1b and IL-10 in the serum and TNF-a and IL-1b in the peritoneal cavity. Lungs from diabetics presented milder ALI that correlated with high levels of SOCS-1, low levels of MyD88 and impaired NFkB activation in alveolar macrophages.
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Método para dimensionamento de pessoal de enfermagem em Centro de Matéria e Esterilização (CME) / Method to calculate nursing staff requirements in the Sterile Processing Department (SPD)

Janaina Anchieta Costa 28 September 2015 (has links)
Introdução: A insuficiência de métodos de dimensionamento que considerem a especificidade do processo de trabalho desenvolvido nas unidades de Centro de Material e Esterilização (CME) tem dificultado a provisão adequada de profissionais de enfermagem na área. Objetivo: Propor um método para o dimensionamento de profissionais de enfermagem em CME, a partir das atividades validadas no estudo de Costa(1). Método: Trata-se de um estudo de natureza quantitativa, do tipo desenvolvimento metodológico, realizado em quatro CMEs de instituições hospitalares públicas e privadas, de grande porte, da cidade de São Paulo. Participaram da pesquisa os profissionais que executaram ações relacionadas ao processamento de materiais nos CMEs, durante a coleta de dados. A pesquisa foi desenvolvida em quatro etapas: mapeamento das atividades em posições de trabalho; determinação do tempo padrão de processamento dos materiais em cada posição de trabalho; estabelecimento da carga média diária de trabalho em cada posição de trabalho; cálculo do quantitativo de profissionais de enfermagem em CME. Resultados: As atividades foram mapeadas em 15 posições de trabalho relacionadas à cinco áreas de trabalho do CME. Para a obtenção do valor médio de tempo de cada posição de trabalho foram mensuradas 1315 amostras de ciclos de trabalho. O tempo padrão de processamento de materiais em cada posição de trabalho foi determinado a partir do resultado do tempo médio de processamento dos kits, acrescentando-se os valores correspondentes ao ritmo do trabalhador e de tolerância para o atendimento das necessidades pessoais e de fadiga. No CME I a carga média de trabalho diária obtida foi de 217,4 horas; no CME II o resultado foi de 294,0 horas; no CME III obteve-se um valor de 123,1 horas e no CME IV a carga média de trabalho foi de 189,1 horas. Para comparar o quadro de pessoal esperado, obtido por meio do método e dos parâmetros propostos, com o quadro de pessoal observado nos CMEs, foi realizado o teste do Qui quadrado (C2) ao nível de significância de 5%. O resultado desse teste possibilitou afirmar que o valor calculado não difere do valor observado em todas as unidades de CME. Conclusão: A presente investigação possibilitou propor, além de parâmetros de tempo para determinação da carga de trabalho, um método para o dimensionamento de pessoal em CMEs, e apresenta-se como um importante referencial que poderá auxiliar as enfermeiras na elaboração e justificativa de propostas consistentes para o planejamento, alocação e distribuição de profissionais de enfermagem nessas unidades / Introductions: The paucity of quantification methods that take into consideration the specificity of the work process carried out in Sterile Processing Departments (SPD) has hindered the adequate staffing with nursing professionals in this area. Objective: to propose a method to calculate requirements of nursing professionals in the SPD based on the activities validated in the study by Costa(1). Method: This is a quantitative study for methodological development, carried out in four Sterile Processing Departments of large public and private hospitals in the city of São Paulo. Professionals performing all tasks related to the processing of materials in the SPDs participated in data collection. The study was carried out in four stages: mapping of activities in work positions, quantification of standard time for processing of materials in each work position, determination of average daily workload in each position, calculation of the nursing professionals requirements in the SPD. Results - Activities were defined in 15 work positions related to the five work areas of the SPD. To obtain the average time necessary for each work position, 1315 work cycle samples were measured. Standard time for processing materials in each work position was based on average processing time of kits, in addition to the values referring to worker rhythm and tolerance for personal needs and fatigue. In SPD I average daily workload was 217.4 hours, in SPD II it was 294.0 hours, in SPD III it was 123.1 hours and SPD IV the average workload was 189.1 hours. Chi-square test, with significance of 5%, was used in order to compare the estimated staff requirements, obtained according to the proposed methodology and parameters, to the actual staff. Test results show that estimated values are not different from actual values found in SPDs studied. Conclusion: The present study allowed us to propose time parameters to determine workload, as well as a method to calculate staffing requirements in SPDs and represents an important reference to help nurses to design and justify consistent proposals to estimate, allocate and distribute nursing professionals in these departments
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Recherche de neutrinos lourds avec l'expérience T2K / Search for heavy neutrinos with the T2K experiment

Lamoureux, Mathieu 26 June 2018 (has links)
La masse non-nulle des neutrinos rend nécessaire l'introduction de nouvelle physique pour expliquer celle-ci. Par exemple, l'ajout de neutrinos lourds avec une masse de l'ordre du GeV permettrait d'expliquer à la fois la masse des neutrinos et l'asymétrie matière-antimatière dans l'Univers, comme cela est proposé dans le modèle nuMSM.Un domaine de masse particulièrement intéressant pour ces nouvelles particules est celui entre 140 et 493 MeV/c^2, qui est accessible avec les expériences actuelles, en particulier avec le détecteur proche ND280 de l'expérience T2K, expérience d'oscillation des neutrinos située au Japon.L'analyse vise à isoler un échantillon de désintégrations de neutrinos lourds dans ND280, après leur production dans la désintégration de kaons chargés dans le faisceau de T2K. Le bruit de fond provenant d'interactions de neutrinos a été réduit à quelques événements dans l'ensemble des données de T2K (2010-2017), ce qui permet de contraindre l'espace des paramètres des neutrinos lourds de manière compétitive par rapport aux expériences dédiées comme PS191.Une des étapes importantes de l'analyse consiste à valider les algorithmes de reconstruction et les simulations du bruit de fond attendu, ce qui a nécessité d'étudier les interactions de neutrinos actifs dans les murs des TPCs; Cet échantillon a également pu être utilisé pour des études de physique.Un dernier travail effectué durant cette thèse concerne la mise à niveau du détecteur ND280, prévue d'ici 2021, dans le but d'augmenter la précision des mesures de section efficace d'interaction des neutrinos afin d'améliorer les analyses des oscillations. / Non-zero neutrino mass requires the introduction of new physic beyond the Standard Model. For instance, the nuMSM (Neutrino Minimal Standard Model) predicts the existence of new heavy neutrinos, with masses at GeV-scale, that would explain both neutrino masses and baryon asymmetry in the Universe.A particularly interesting mass domain is between 140 and 493 MeV/c^2, which is accessible to current experiments, in particular with the near detector ND280 of the T2K experiment, which is a long baseline neutrino oscillation experiment located in Japan.The analysis aims at the selection of a sample containing heavy neutrino decays, after they have been produced in kaon decays along the standard T2K neutrino beam. Background coming from standard neutrino interactions has been reduced to few events in the current dataset (2010-2017), which allow to constrain heavy neutrino parameter space quite well with respect to dedicated experiments such as PS191.An important step in the analysis consists in the validation of the reconstruction algorithms and of the expected background. It has been done with the study of active neutrino interactions in the walls of the TPCs. This sample is also interesting per se for physics.A last topic in this thesis concerns the upgrade of the near detector, that is scheduled for 2021. The goal is to improve neutrino cross-section measurements in order to get more precise determination of oscillation parameters.
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Evaluation of genetic engineering and genome editing tools to develop multifactorial reproductive sterility or killing sperm systems for the improvement of the Sterile Insect Technique

Eckermann, Kolja Neil 19 October 2021 (has links)
No description available.
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Characterization of sterile tassel silky earl: A Homeotic B-Class Gene Involved in Specification of Floral Organ Identity In Zea mays

Williams, Steven Keith 12 December 2012 (has links) (PDF)
Specification of floral organ identity in angiosperm flowers is accomplished by the coordinated activity of A-, B-, C-, and E-class MADS-box genes. In the eudicots, B-class genes specify petal and stamen identity. This eudicot B-class function depends on the simultaneous expression of genes from two paralogous B-class lineages (the DEFICIENS/APETALA3 lineage and the GLOBOSA/PISTILLATA lineage). Proteins produced by genes from these two lineages interact as obligate heterodimers and together regulate the transcription of various downstream targets. These obligate heterodimers also positively regulate the transcription of the B-class genes themselves, thereby mediating a unique B-class autoregulatory feedback loop. There is compelling evidence that B-class function at the phenotypic and molecular level is highly conserved among the eudicots. The degree to which B-class homeotic function, obligate heterodimerization, and autoregulation are conserved in non-eudicot, however, remains a topic of debate. Here we describe loss of function in Sterile tassel silky ear1 (Sts1) a maize ortholog of GLOBOSA/PISTILLATA formerly known as Zmm16. Mutation in Sts1 results in homeotic transformation of lodicules and stamens into bract-like organs in male inflorescences. Female inflorescences are affected in a similar manner. Stamens in these inflorescences are, however, transformed into carpels instead of into bract-like organs. This mutant phenotype suggests that Sts1 has a B-class homeotic function. Using qRT-PCR we also demonstrate that Sts1 participates in positive transcriptional regulation of all of the maize B-class genes. These findings suggest a high degree of B-class functional conservation between the monocots and the eudicots. Analysis of tasselseed1/sts1 and grassy tillers1/sts1 double mutants suggests that maize B-class genes also play a role in the sex determination process.

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