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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.
81

Controle da mancha preta dos frutos cítricos mediante manejo cultural

Bellotte, José Antônio Miranda [UNESP] 31 March 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:28:32Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-03-31Bitstream added on 2014-06-13T20:18:19Z : No. of bitstreams: 1 bellotte_jam_me_jabo.pdf: 523569 bytes, checksum: 592afd8fed1a89998777898d47c64765 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O presente estudo foi desenvolvido em pomares de citros localizados em propriedade comercial na região de Rio Claro-SP e teve como objetivo a determinação do efeito de práticas culturais na redução das fontes de inóculo e, conseqüente diminuição da severidade da mancha preta dos frutos cítricos, causada por Guignardia citricarpa. Desenvolveram-se dois experimentos em áreas distintas. No primeiro ensaio, testou-se a influência de cultivos intercalares, amendoim forrageiro e capim coastcross e posterior roçagem da massa formada sob a copa de laranjeiras 'Natal', na flutuação populacional de ascósporos e na severidade da doença, enquanto que no segundo, foi avaliado o efeito de diferentes tratamentos [(1) uréia 12,5 g/litro; (2) nitrato de cálcio 12,5 g/litro; (3) calcário dolomítico 2 t/ha; (4) microrganismos eficazes 1% do produto ativado; (5) combinação dos produtos comerciais Stuble Aid® + Compostaid® 0,75 mL/litro + 0,75 g/litro e (6) Testemunha] na aceleração da decomposição de folhas de limoeiros 'Siciliano' caídas sob a copa das plantas e na severidade da doença. Concluiu-se que o capim coastcross foi a espécie mais eficiente na supressão da liberação de ascósporos, com conseqüente redução da severidade da doença. No segundo ensaio, os tratamentos representados pela adição de microrganismos foram os mais eficientes na aceleração da decomposição de folhas de limoeiro, porém quanto à severidade da doença, todos os tratamentos apresentaram o mesmo comportamento, com reduções significativas em relação à testemunha. / The present research was developed in citrus orchards located in commercial property in Rio Claro - SP region and it had as an objective the determination of the effect of cultural practice in the reduction of the source of inoculum and, consequently the reduction of strictness black spots in citric fruit, caused by Guignardia citricarpa. Two experiments in distinct areas were developed. In the first one, the influence of intercalary culture (peanut and coastcross grass) and later the skim of the a dough formed on the orange trees top 'Natal', in the floating of ascospores and in the strictness of the disease, while in the second experiment, the effect of different treatments were evaluated [(1) urea 12,5 g/liter; (2) calcium nitrate 12,5 g/liter; (3) dolomitic calcareous 2t/ha; (4) efficient microrganisms 1% from the active product; (5) the combination of the commercial products Stuble Aid® + Compostaid® 0,75 mL/liter + 0,75 g/liter and (6) Control] in the acceleration of the 'Siciliano' lemon trees leaves decomposition fallen down on the top trees and in the severity of the disease. It was concluded that the coastcross grass was the most efficient species in the supression of the discharge of the ascospores and in the decrease of the severity disease. In the second experiment, the treatments represented by the addition of microorganisms were the most efficient in the acceleration of the lemon trees leaves decomposition, however as for the severity of the disease, all the treatments presented the same performance, with statistically significative decreases in relation to control.
82

Homossexualidades e homossociabilidades : hierarquização e relações de poder entre Homossexuais masculinos que freqüentam dispositivos de socialização de sexualidades Glbttt /

Nascimento, Márcio Alessandro Neman. January 2007 (has links)
Orientador: Fernando Silva Teixeira Filho / Banca: Wiliam Siqueira Peres / Banca: Paulo Roberto de Carvalho / Resumo: Este trabalho problematiza a questão dos modos de subjetivação e as relações hierárquicas e de exercício de poder que gravitam em torno das homossexualidades masculinas, freqüentadores de dispositivos (lugares) de socialização de sexualidades GLBTTT. Descrições históricas indicam que desde a Grécia Antiga, sanções às práticas homoeróticas são recorrentes, porém, é com o surgimento do personagem homossexual no século XIX que as injúrias e perseguições se direcionaram para o sujeito homossexual. Ainda que, ambientes freqüentados para encontros homoeróticos sempre existiram, é apontado pela história que, a partir do século XIV, idéias eugenistas, higienistas e heteronormativas enfocaram na segregação de lugares e programas familiares em contraposição a lugares onde se aglutinavam as escórias da sociedade, os quais deveriam ser tratados com diferenciação e violência. Partindo do exposto, surgem os dispositivos de socialização freqüentados também por homossexuais, os chamados popularmente, por esses freqüentadores, guetos gays. No entanto, é fato que a violência sofrida pelos homossexuais, sugere um novo caráter expressivo e crescente - a relação de poder e hierarquização entre os próprios homossexuais. O objetivo deste trabalho é descrever as relações estabelecidas entre os homossexuais que freqüentam estes dispositivos e o sentido que estes lugares tiveram e vêm adquirindo ao longo de suas existências, partindo dos pressupostos teóricos dos estudos culturais e de gênero de autores pós-estruturalistas. Para tal pesquisa, realizaram-se observações etnográficas nestes locais em um município do interior paranaense, assim como se realizaram entrevistas prolongadas com freqüentadores selecionados e que ocasionaram em análises das narrativas de histórias de vida ...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This study problematizes the ways of subjection and hierarchical relations and also the power actions that surround male homosexulaties, attenders of GLBTTT sexualities socialization spots (places). Historical descriptions show that since Ancient Greece, punishments for homoerotic practices were carried out, nevertheless, it was with the appearance of the homosexual character from the XIX century that those injuries and persecutions headed towards the homosexual character. Even though spots attended by homoerotic meetings have always existed, it is shown through history that, since the XIV century, eugenistic, hygienistic and heteronormative ideas focused on the segregation of places and family programs and also in opposition to places where the society mob gathered, which should be tread with differentiation and violence. Due to the aforementioned, socialization spots also attended by homosexuals are creaated, the popularly so-called, by these attenders, gay ghettos. However, it is a fact that the violence faced by these homosexuals suggests a new expressive and growing character - a power and hierarchy relation among the homosexuals themselves. The objective of this study is to describe the relations established among homosexuals who attend these spots and the meaning that these environments have had and are acquiring through their existence, based on cultural and gender studies from post-structuralist authors. In order to perform such research, ethnographic observations were carried out in those places in an inland town from Parana State, as well as long interviews with selected attenders what resulted in analyses of these characters-participants' lifetime narratives. The analyses of the ...(Complete abstract, click electronic access below) / Mestre
83

On the vegetation front dynamics generated by strong versus weak nonlocal interactions

Fernández Oto, Cristian 22 November 2016 (has links)
Dans cette thèse, nous étudions différentes structures de végétation issues de l’auto-organisation spatiale. Ce phénomène est visible dans des zones (semi-)arides où le potentiel d’évaporotranspiration dépasse sensiblement la moyenne des précipitations annuelles. Ce déficit hydrique freine le développement des plantes individuelles et, au niveau communautaire, stimule des comportements de « clustering » même si la topographie est isotrope. Dans ce contexte, nous adoptons une approche basée sur l’équation F-KPP non-locale permettant de formuler ces hypothèses en termes de propriétés des plantes individuelles.Une partie importante de cette thèse concerne l’étude d’un exemple de structure de végétation localisée bien connu dans la littérature, les cercles de fées. Les cercles de fées ont été découverts dans le désert de Namibie. Cependant, ces dernières années, ils ont aussi été observés en Australie. Plusieurs hypothèses ont été proposées dans la littérature. Nous proposons la compétition non-locale forte entre plantes individuelles (en utilisant un noyau de type Lorentzien) comme ingrédient principal pour expliquer la formation des cercles de fées. Le couplage non-local fort influence l’interaction entre fronts dans le régime bistable (loin de toute forme d’instabilité briseuse de symétrie). Dans le cas d’un couplage non-local faible, par exemple dans un noyau Gaussien, l’interaction entre fronts est toujours attractive. Par conséquent, les structures localisées qui résultent de l’interaction des fronts sont instables. Le couplage non-local fort peut induire la stabilisation de structures localisées que nous interprétons comme étant des cercles de fées. Notre mécanisme permet d’expliquer les principales caractéristiques des cercles de fées, comme la relation entre leur diamètre et la disponibilité des ressources. De plus, nous avons appliqué ces résultats à d’autres modèles de végétation. Nos résultats concordent avec les observations sur le terrain.Nous avons analysé la formation de « spots » de végétation dans la région Andine en Bolivie. Nous avons étudié comment un modèle standard d’interaction-redistribution génère des « spots », de longueur d’onde d'approximativement 1.36m, via une instabilité qui brise la symétrie. En considérant des paramètres réalistes, nos résultats concordent avec les observations sur le terrain.Enfin, nous avons étudié la formation de structure en forme de spirale dans un système qui couple la végétation et les herbivores dans un modèle proie-prédateur. Nous avons trouvé que le mécanisme qui induit la formation de spirales est l’excitabilité. Nos observations sur le terrain et nos résultats numériques du modèle montrent que les spirales de végétation ont une profondeur de quelques centimètres et une longueur de quelques mètres. En ce qui concerne l'échelle de temps, nos estimations donnent une période de rotation de l’ordre de 10 ans. / Option Physique du Doctorat en Sciences / info:eu-repo/semantics/nonPublished
84

Reducing Alcohol-Related Crashes by Improving Patrols Through Development and Verification of Hot Spot Route Optimization Models

Buser, Lauren 31 August 2018 (has links)
No description available.
85

Metody predikce aktivních míst v proteinech / Prediction methods of protein hot spots

Duras, Jan January 2012 (has links)
This master's thesis deals with prediction of hot spots in proteins. The theorethical part describes compositions of proteins interfaces and hot spots. There are mentioned basic principles of hot spots prediction. In the practical part is selected method, using the S-Transform, designed to pseudocode and then implmented to Matlab software. Created program is tested on a sample of data and compared with available methods.
86

Identifikace možných vad a jejich prevence ve výrobě kompozitních dílů / Identification of possible defects and their prevention in the composite components manufacturing

Rusek, Jan January 2016 (has links)
A subject of the thesis is the usage of methods of FMEA and application of results on a making process of the Composite Components inc. In the theoretical part, the application of methods of FMEA are discussed, depending on its usage. The research part is about analysis of current situation of the working process of the Composite Components inc. The acquired data are written into PFMEA form. The corrective precautions leading to decreasing defects are designed and evaluated.
87

Experimental Study of a Low-Voltage Pulsed Plasma Thruster for Nanosatellites

Patrick M Gresham (12552244) 17 June 2022 (has links)
<p>The commercial CubeSat industry has experienced explosive growth recently, and with falling  costs  and  growing  numbers  of  launch  providers,  the  trend  is  likely  to  continue.  The scientific missions CubeSats could complete are expanding, and this has resulted in a demand for reliable  high  specific  impulse  nanosatellite  propulsion  systems.  Interest  in  liquid-fed  pulsed plasma thrusters (LF-PPTs) to fulfill this role has grown lately. Prior work on a nanosatellite LF-PPT was done in the Purdue Electric Propulsion and Plasma Laboratory, but its high operational voltage and electrode size would be disadvantageous for integration on a CubeSat, which have strict volume limitations and provide only tens of Watts in power at low voltages. This work aims to address those disadvantages and further advance the development of a nanosatellite LF-PPT by reducing the operating voltage and removing long plate electrodes to prevent energy losses on components other than the expelled plasma sheet. Two major objectives are pursued: to construct a  coaxial  pulsed  plasma  thruster  operating  with  10s  to  100s  of  volts  and  to  characterize  the temporal evolution of the discharge parameters in this low-voltage operation scenario. </p> <p>It  took  three  experimental  design  iterations,  all  of  which  used  a  260  <em>uF</em> ,  400 <em>V</em> film capacitor, to arrive at a functional coaxial pulsed plasma thruster. First, a button gun was tested. It produced  a  peak  current  of ~16<em> kA</em>,  which  serves  as  the  expected  maximum  for  the  later experiments. Due to the presence of parasitic arcing, it revealed that electrical lines needed to be removed from vacuum chamber to enable testing at a wide range of pressures. Second, a coaxial PPT was designed, built, and tested. This design confirmed operation at discharge voltages <100 <em>V</em> across the plasma, achieving one of the project’s aims, and produced a peak current of 7.4 <em>kA</em>. However,  necessity  to  better  align  the  cathode and  provide  an  unobstructed  camera  view  for observation of the discharge column attachment to the cathode surface forced additional system redesign. Third, a revised coaxial PPT was built and tested. Using air as a propellant, the discharge generated a peak current of 10.4 <em>kA</em> at a mass flow rate of 2 mgs. The PPT cathode was imaged with an ICCD camera over a wide range of pressures, and the photos indicated “spotless” diffuse arc attachment to the cathode, which serves as evidence to expect low erosion rates. The direct measurements of the cathode erosion rate are planned for future. </p>
88

Crime Concentration in Sweden : An Explorative Test of a Criminological Law

Breski, Robert January 2021 (has links)
According to the law of crime concentration, a certain percentage of crime is predicted to be concentrated at a certain percentage of microgeographic units, and relatively large amounts of crime are predicted to be accounted for by a small percentage of places. Given the lack of research testing the law in a Swedish context and for a whole country, this study set out to examine the concentration of crime at all densely populated areas in Sweden. Analyzing national grid net data, where all densely built-up areas of Sweden were divided into 250 x 250 meter pixels with added police recorded crime data, the study aimed to examine how many percent of the pixels are required to account for 25, 50 and 80% of the crimes in all densely populated areas; how the concentrations differ between small, medium-sized and big cities; how the concentrations differ between violent and property crimes in all of the country; and how an observed crime concentration compares to a counterfactual, randomized concentration. The results indicated a crime concentration that is stronger than the ones observed in most previous studies, with just 0.4, 2.3 and 10.2% of the pixels accounting for 25, 50 and 80% of all crimes in all densely populated areas, respectively. In line with previous research, the results also showed that crime is more strongly concentrated in smaller cities compared to the big ones, that violent crime is more strongly concentrated than property crime, and that the observed concentration of violent crime is considerably stronger than a counterfactual, randomized concentration in the form of a Poisson distribution. Further research on crime concentration in Sweden is requested to build on these findings.
89

Structural stability and lipid interactions in the misfolding of human apolipoprotein A-I: what makes the protein amyloidogenic?

Das, Madhurima 09 March 2017 (has links)
High-density lipoproteins and their major protein, apolipoprotein A-I (apoA-I), remove excess cellular cholesterol and protect against atherosclerosis. However, in acquired amyloidosis, non-variant full-length apoA-I deposits as fibrils in arteries contributing to atherosclerosis. In hereditary amyloidosis (AApoAI), a potentially fatal disease, N-terminal fragments of variant apoA-I deposit in vital organs and damage them. There is no cure for apoA-I amyloidosis and its structural basis is unknown. Previously, AApoAI mutations were mapped on the crystal structure of the human C-terminally truncated Δ(185-243)apoA-I. The results suggested that the mutation-induced destabilization of the lipid-free protein initiates β-aggregation. Our biophysical studies showed that amyloidogenic mutations G26R, W50R, F71Y and L170P did not necessarily destabilize the native structure, prompting us to search for additional triggers of apoA-I misfolding. We mapped residue segments predicted to promote β-aggregation (termed amyloid hot spots) on the atomic structure of ∆(185-243)apoA-I. The results suggested that perturbed packing of these hot spots, particularly residues 14-22, triggers amyloidosis. This enabled us to propose the first molecular mechanism of apoA-I misfolding. To explore a potential mechanism, we combined structural, stability, dynamics and functional studies of several amyloidogenic mutants and a non-amyloidogenic control, L159R. All mutants reduced structural protection of the segment 14-22, supporting our hypothesis that increased dynamics of this segment triggers AApoAI. The non-amyloidogenic mutant showed helical unfolding near the mutation site indicating susceptibility to proteolysis. We propose that the major factors that make apoA-I amyloidogenic are reduced protection of the major amyloidogenic segments combined with the structural integrity of the four-helix bundle to facilitate protein aggregation. Together, our results suggest that the fate of apoA-I in vivo depends on the balance between its misfolding, proteolysis, and protective protein-lipid interactions. Our structural and bioinformatics analysis of other members of the apolipoprotein family (A-II, A-IV, A-V, B, C-I, C-II, C-III, E, SAA) showed that apolipoproteins’ propensity to form amyloid is rooted in the proteins’ hydrophobicity, which is key to the lipid binding ability. The overlap of functional and pathologic interfaces suggests competition between normal protein function and misfolding. Therefore, increasing apolipoprotein retention on the lipid surface provides a potential therapeutic strategy against amyloidosis.
90

Ecology of Xanthomonas campestris pv. vitians in relation to development of bacterial leaf spot of lettuce by Vicky Toussaint.

Toussaint, Vicky. January 2001 (has links)
No description available.

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