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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.
91

Reconstruction theories of non-ideal games

Wei, Mo 28 November 2006 (has links)
No description available.
92

Analyzing Reservoir Thermal Behavior By Using Thermal Simulation Model (sector Model In Stars)

Samadov, Hidayat 01 June 2011 (has links) (PDF)
It is observed that the flowing bottom-hole temperature (FBHT) changes as a result of production, injection or shutting the well down. Variations in temperature mainly occur due to geothermal gradient, injected fluid temperature, frictional heating and the Joule-Thomson effect. The latter is the change of temperature because of expansion or compression of a fluid in a flow process involving no heat transfer or work. CMG STARS thermal simulation sector model developed in this study was used to analyze FBHT changes and understand the reasons. Twenty three main and five additional cases that were developed by using this model were simulated and relation of BHT with other parameters was investigated. Indeed the response of temperature to the change of some parameters such as bottom-hole pressure and gas-oil ratio was detected and correlation was tried to set between these elements. Observations showed that generally FBHT increases when GOR decreases and/or flowing bottom-hole pressure (FBHP) increases. This information allows estimating daily gas-oil ratios from continuously measured BHT. Results of simulation were compared with a real case and almost the same responses were seen. The increase in temperature after the start of water and gas injection or due to stopping of neighboring production wells indicated interwell communications. Additional cases were run to determine whether there are BHT changes when initial temperature was kept constant throughout the reservoir. Different iteration numbers and refined grids were used during these runs to analyze iteration errors / however no significant changes were observed due to iteration number differences and refined grids. These latter cases showed clearly that variations of temperature don&rsquo / t occur only due to geothermal gradient, but also pressure and saturation changes. On the whole, BHT can be used to get data ranging from daily gas-oil ratios to interwell connection if analyzed correctly.
93

Synthesis of Metallic Nanowires Using Integrated DNA Molecules as Templates

Erler, Christiane 24 March 2010 (has links) (PDF)
The DNA double helix is inherently a nanoscale wire-like object, possessing a 2 nm diameter as well as a remarkable capability for molecular recognition and the interaction with other chemical compounds, thus making it an attractive material for biologically driven assembly of artificial nanostructures. In this work methods for the construction of functional electronic networks from single DNA molecules are presented. For this, (i) the generation of patterns of distinct interconnects between micro-fabricated contact pads are explored by stretching end-specifically thiol-functionalized, single-tethered DNA molecules using hydrodynamic flow as well as an electric field-induced thermal flow. (ii) These networks then serve as a template for a selective in-situ photoinduced nucleation and growth of platinum clusters of 4 nm diameter along the DNA molecules. In the synthesis exclusively platinum ions from an aqueous platinum nitrate solution bonded electrostatically to the backbone of the immobilized DNA can be reduced upon irradiation with UV light, while background metallization is inhibited. Furthermore, the metallization scheme is applied to DNA nanotubes and another photochemical deposition process is used to tune the interparticle gap space in a discontinuous platinum cluster chain to form conducting nanowires. The "process toolbox'' presented in this work offers a versatile alternative for the hierarchical patterning and incorporation of biotemplated nanomaterials into micro-/nanofabrication schemes. / Ein doppelhelikaler DNA-Strang besitzt mit seinem hohen Aspektverhältnis von Natur aus Ähnlichkeit mit einem Kabel. Zusammen mit seinen einzigartigen Selbstassemblierungseigenschaften sowie der Fähigkeit, mit einer Vielzahl von chemischen Stoffen eine Verbindung einzugehen, macht dies ihn zu einem aussichtsreichen Baumaterial für den Aufbau von künstlichen Nanostrukturen. In dieser Arbeit werden deshalb verschiedene Methoden für den Bau von elektronischen Schaltkreisen aus einzelnen DNA-Strängen demonstriert. Dazu wird (i) die Herstellung von Verdrahtungsmustern zwischen lithographisch gefertigten Kontaktstrukturen untersucht. Endständig mit Thiolgruppen funktionalisierte DNA-Moleküle, die an nur einem Ende mit der Oberfläche verknüpft sind, werden mittels Strömung oder eines elektrothermisch induzierten Flusses zwischen Elektroden gespannt. (ii) Diese Netzwerke dienen im Weiteren als Vorlage für ein selektives, lichtinduziertes Wachstum von Platinpartikeln mit Durchmessern von 4 nm lokal entlang der DNA-Moleküle. Dabei werden unter UV-Bestrahlung nur solche Platinionen reduziert, die aus einer Platinnitrat-Lösung elektrostatisch an die immobilisierte DNA angebunden haben. Partikelwachstum in der umgebenden Lösung wird weitgehend verhindert. Darüber hinaus wird dieses Verfahren auch auf DNA-Nanoröhren angewendet und ein weiterer photochemischer Abscheideprozess eingesetzt, um unterbrochene Clusterkettern zusammenzuwachsen, mit dem Ziel, elektrisch leitfähige Nanodrähte zu erhalten. Die vorgestellten Verfahren stellen eine vielseitige Alternative zu herkömmlichen, hierarchischen Fabrikationsschemen der Mikro- und Nanotechnologie dar.
94

OBSERVATIONS OF THE SPACE-TIME STRUCTURE OF FLOW, VORTICITY AND STRESS OVER ORBITAL-SCALE RIPPLES

Hare, Jenna 28 May 2013 (has links)
The spatial and temporal structure of the flow, vorticity and stress over equilibrium orbital-scale sand ripples are investigated at turbulence-resolving scales with a wide-band coherent Doppler profiler (MFDop) in an oscillating tray apparatus. The oscillation period and horizontal excursion were 10 s and 0.5 m. Velocity profiles were acquired with 3 mm vertical resolution and at a 42 Hz sampling rate. Ripple wavelength and amplitude were 25 cm and 2.2 cm. The MFDop measurements are used to investigate the development of the lee vortex as a function of phase, and the co-evolution of turbulent kinetic energy, Reynolds stress and turbulence production. Shear stress is determined from the vertically-integrated vorticity equation and using the double-averaging approach. Friction factors obtained from the two methods are comparable and range from 0.1 to 0.2.
95

SUPPLIER SUSTAINABILITY EVALUATION UTILIZING MULTI ATTRIBUTE UTILITY MODELING

Ladd, Scott E. 01 January 2013 (has links)
Conventionally, the focus during supplier evaluation has been to assess cost, quality and delivery effectiveness due to their impact on profitability. In recent years, there has been increased emphasis on promoting more sustainable business practices that focus on reducing environmental impact and improve societal well-being, in addition to economic benefits. However, most of the existing supplier evaluation methods in literature as well as those used by leading companies fall short of comprehensively assessing suppliers from a Triple Bottom Line (TBL) perspective. TBL defined as holistically looking at the economic, environmental, and societal aspects of an entity. This paper presents a review and selection of metrics for economic, environmental and societal sustainability evaluation. In addition, this work proposes a methodology for combining the scores into a comprehensive score that can be used to compare two entities performance relative to the TBL.
96

Perspektiv på goodwill : En studie om användningen av teoretiska begrepp i praktiken / Goodwill perspectives : A study of the practical use of theoretical concepts

Larsson, Therese, Pettersson, Louise January 2014 (has links)
Det finns två typer av goodwill, den första typen är internt upparbetad goodwill och den andra typen är goodwill som uppkommer vid förvärv av företag. Fokus i denna uppsats kommer att ligga på den förvärvade goodwill, som kan upplevas som en svart låda då det kan vara oklart vad posten faktiskt består av. Förvärvad goodwill kan definieras på olika sätt av företagen, i den akademiska världen har främst två perspektiv identifierats, top-downperspektivet och bottom-upperspektivet. Ur den första synvinkeln ses goodwill som en restpost och ur den andra synvinkeln kan goodwill ses som en summa av de komponenter som posten består av. Genom att betrakta dessa perspektiv är tanken att få en inblick i hur företagen väljer att redovisa sin goodwill. Det kan vara lättare sagt än gjort, teori och praktik går inte alltid hand i hand. Det finns ett glapp mellan hur praktiker jobbar med goodwill och teoretikers åsikt om posten. Varför det finns meningsskiljaktigheter växer successivt fram under studiens gång. Det finns än så länge bara ett fåtal studier som behandlar själva begreppet goodwill och dess olika perspektiv samt hur företagen ser på goodwill. För att försöka bidra till ökad förståelse på detta område, har vi i denna uppsats undersökt om teorin och praktiken kommit varandra närmare. Det främsta syftet med studien är att ta reda på om företag inom bemanningsbranschen definierar sin goodwill olika i sina årsredovisningar. För att undersöka detta på ett begripligt sätt har tre professionella respondenter intervjuats i ett försök att klargöra komplexiteten av posten.   Slutsatsen är att det inte går att identifiera vilket perspektiv som används i en årsredovisning på grund av att dessa är väldigt standardiserade, vilket gör att det blir svårt för intressenten att utläsa särskilt mycket information om goodwillposten.  Det alternativ som kändes mest relevant att använda och som skulle hjälpa oss att kunna få klarhet i vår frågeställning, var att vända sig till en urvalsgrupp av representanter på området. Den analys som efterföljde resulterade i att vi kunde konstatera att samtliga svarande på det praktiska området såg goodwillposten mer eller mindre som en restpost. Ingen värdering eller starkare reflektion gjordes kring det andra teoretiska perspektivet. Sammanfattningsvis vågar vi påstå att det inte skett någon märkbar förändring som gjort att teori och praktik närmat sig varandra. / There is two ways to understand goodwill. Number one, internally generated goodwill and number two, acquired purchase goodwill. The main topic for this research is acquired purchase goodwill. Many people believe that goodwill is a sort of black box.  It is unclear what goodwill actually is. There is no limit on how you can define acquired purchase goodwill. In academia we talk about two perspectives, top-down perspective and bottom-up perspective. The first perspective sees goodwill as a residual and the second perspective sees goodwill as a sum of its components. When you put on these two glasses, the idea is that you may be able to see how businesses account for their goodwill. It is easier said than done, many times theory and practice does not get along. There is a big space between the theories on how you work with goodwill in the reality. Only a few have studied the definition of goodwill. Because of that we really wanted to investigate this phenomenon. We have analyzed if the gap between theory and reality has been reduced. The purpose of this study is to investigate if the staffing companies define goodwill different in their annual reports. The tool we have used is to interview professional accountants to get their opinion. The conclusion is that the annual report is quite standardized which means it is difficult to understand what goodwill actually is. Everybody we interviewed have the same opinion, that goodwill is a residual. They made no reflections or additions on that subject. In summary, we know now that after our study, no big change has been made between theory and practice.
97

Evolution of Seabed Pockmarks in Penobscot Bay, Maine

Gontz, Allen M January 2002 (has links) (PDF)
No description available.
98

Distribuição espacial do pico e ultraplâncton na plataforma continental e talude entre Cabo Frio (RJ) e Ubatuba (SP) e sua relação com a hidrodinâmica local: inverno de 2010 / Spatial distribution of pico and ultraplankton on the continental shelf and slope between Cabo Frio (RJ) and Ubatuba(SP) and its relationship with the local hydrodynamics: Winter 2010

Nathália Oliveira de Castro 27 April 2012 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O picoplâncton (0,2 - 2,0 m) e ultraplâncton (> 2,0 - 5,0 m) despertam interesse por utilizarem ativamente a matéria orgânica dissolvida, estabelecendo a alça microbiana. Responsáveis por 50-80% da produção primária em águas oligotróficas, essas frações apresentam elevadas eficiência luminosa e razão superfície/volume que as permitem alcançar alto desenvolvimento mesmo sob baixas luminosidade e disponibilidade de nutrientes. Buscando relacionar a distribuição espacial e composição da comunidade pico e ultraplanctônica aos controles bottom-up na plataforma continental e talude ao largo dos Estados do Rio de Janeiro e São Paulo (22S a 26S), foram coletadas amostras de água em 39 estações oceanográficas e utilizadas as imagens dos sensores MODIS Terra e Aqua, bem como dados de hidrografia, para a descrição dos fenômenos oceanográficos de mesoescala. A abundância total de ambas as frações de tamanho, assim como a dominância do picoplâncton, reduziu em função do distanciamento da costa. Os organismos autotróficos foram em média (102 cél.mL-1 a 104 cél.mL-1 ) majoritariamente uma ordem de grandeza inferiores aos heterotróficos (103 cél.mL-1 a 105 cél.mL-1). A Água Central do Atlântico Sul (ACAS) e as plumas das baías de Guanabara e Sepetiba (RJ) permaneceram na plataforma interna favorecendo o aumento na concentração dos macronutrientes e refletindo na mudança da estrutura da comunidade através do aumento da contribuição de autótrofos no centro da plataforma, principalmente do ultraplâncton à superfície (cerca de 21%) e na profundidade do máximo de clorofila (44%). O transporte de águas costeiras carreadas por uma corrente de origem sul gerou o vórtice de plataforma identificado nas imagens de satélite para a região da plataforma interna de Ubatuba (SP), onde concentrações mais elevadas de amônio (0,28 M) e fosfato (9,64 M) a partir dos 50 m sustentaram maior densidade do ultra autótrofo (2,89 x 103 cél.mL-1) que superou a densidade de heterótrofos (2,50 x 103 cél.mL-1) no máximo de clorofila. Os resultados destacaram um forte gradiente nerítico-oceânico na distribuição dos organismos. Sugerem ainda a predominância do metabolismo heterotrófico na maior parte das águas oligotróficas da plataforma e talude entre o Rio de Janeiro e São Paulo, bem como a presença de caráter autotrófico naquelas regiões influenciadas por feições de mesoescala, como plumas estuarinas e vórtices de plataforma. / The picoplankton (0.2 2.0 m) and ultraplankton (>2.0 5.0 m) arouse interest because they actively use the dissolved organic matter and establishe the microbial loop. Responsible for 50-80% of primary production in oligotrophic waters, these fractions have high luminous efficiency and high surface/volume ratio that enable them to achieve high development even under low light and low nutrient availability. Seeking to relate the spatial distribution and composition of pico and ultraplanktonic community to the bottom-up control and mesoscale oceanographic features in the Brazilian continental shelf and slope off Rio de Janeiro and São Paulo (22S to 26S), water samples were taken in 39 oceanographic stations and images of MODIS Terra and Aqua sensors, toghether with hidrography, were employed to decribe the mesoscale oceanographic features.The total abundance of both size fractions, as well as the dominance of picoplankton, decreased as a function of distance from the coast. Autotrophic organisms were, predominantly, on average (102 cell.mL-1 to 104 cell.mL-1) one order of magnitude lower than the heterotrophic (103 cell.mL-1 to 105 cell.mL-1). The South Atlantic Central Water (SACW) and the plumes of Guanabara and Sepetiba bays (RJ) remained in the inner shelf favoring an increase in macronutrients concentration and reflecting changes in community structure by the increase of autotrophs contribution, especially in the central portion of the shelf, mainly ultraplankton at surface (21%) and in maximum chlorophyll depth (44%). The transport of coastal waters carried by a current from south caused the shelf eddy identified by water colour/chlorophyll images for the region of Ubatuba inner shelf (SP), where high concentrations of ammonium (0,28 M) and phosphate (9,64 M) near the depth of 50 m supported higher density of autotrophic ultraplankton (2.89 x 103 cells.mL-1) which exceeded the density of heterotrophs at the chlorophyll maximum (2.19 x 103 cells.mL-1). Our results highlighted a strong neritic-oceanic gradient in the distribution of these organisms. They also suggest the predominance of the heterotrophic metabolism in the majority of the oligotrophic waters of the shelf and slope between Rio de Janeiro and São Paulo, as well as the presence of an autotrophic nature in those regions influenced by mesoscale features, such as estuarine plumes and shelf eddies.
99

Distribuição espacial do pico e ultraplâncton na plataforma continental e talude entre Cabo Frio (RJ) e Ubatuba (SP) e sua relação com a hidrodinâmica local: inverno de 2010 / Spatial distribution of pico and ultraplankton on the continental shelf and slope between Cabo Frio (RJ) and Ubatuba(SP) and its relationship with the local hydrodynamics: Winter 2010

Nathália Oliveira de Castro 27 April 2012 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O picoplâncton (0,2 - 2,0 m) e ultraplâncton (> 2,0 - 5,0 m) despertam interesse por utilizarem ativamente a matéria orgânica dissolvida, estabelecendo a alça microbiana. Responsáveis por 50-80% da produção primária em águas oligotróficas, essas frações apresentam elevadas eficiência luminosa e razão superfície/volume que as permitem alcançar alto desenvolvimento mesmo sob baixas luminosidade e disponibilidade de nutrientes. Buscando relacionar a distribuição espacial e composição da comunidade pico e ultraplanctônica aos controles bottom-up na plataforma continental e talude ao largo dos Estados do Rio de Janeiro e São Paulo (22S a 26S), foram coletadas amostras de água em 39 estações oceanográficas e utilizadas as imagens dos sensores MODIS Terra e Aqua, bem como dados de hidrografia, para a descrição dos fenômenos oceanográficos de mesoescala. A abundância total de ambas as frações de tamanho, assim como a dominância do picoplâncton, reduziu em função do distanciamento da costa. Os organismos autotróficos foram em média (102 cél.mL-1 a 104 cél.mL-1 ) majoritariamente uma ordem de grandeza inferiores aos heterotróficos (103 cél.mL-1 a 105 cél.mL-1). A Água Central do Atlântico Sul (ACAS) e as plumas das baías de Guanabara e Sepetiba (RJ) permaneceram na plataforma interna favorecendo o aumento na concentração dos macronutrientes e refletindo na mudança da estrutura da comunidade através do aumento da contribuição de autótrofos no centro da plataforma, principalmente do ultraplâncton à superfície (cerca de 21%) e na profundidade do máximo de clorofila (44%). O transporte de águas costeiras carreadas por uma corrente de origem sul gerou o vórtice de plataforma identificado nas imagens de satélite para a região da plataforma interna de Ubatuba (SP), onde concentrações mais elevadas de amônio (0,28 M) e fosfato (9,64 M) a partir dos 50 m sustentaram maior densidade do ultra autótrofo (2,89 x 103 cél.mL-1) que superou a densidade de heterótrofos (2,50 x 103 cél.mL-1) no máximo de clorofila. Os resultados destacaram um forte gradiente nerítico-oceânico na distribuição dos organismos. Sugerem ainda a predominância do metabolismo heterotrófico na maior parte das águas oligotróficas da plataforma e talude entre o Rio de Janeiro e São Paulo, bem como a presença de caráter autotrófico naquelas regiões influenciadas por feições de mesoescala, como plumas estuarinas e vórtices de plataforma. / The picoplankton (0.2 2.0 m) and ultraplankton (>2.0 5.0 m) arouse interest because they actively use the dissolved organic matter and establishe the microbial loop. Responsible for 50-80% of primary production in oligotrophic waters, these fractions have high luminous efficiency and high surface/volume ratio that enable them to achieve high development even under low light and low nutrient availability. Seeking to relate the spatial distribution and composition of pico and ultraplanktonic community to the bottom-up control and mesoscale oceanographic features in the Brazilian continental shelf and slope off Rio de Janeiro and São Paulo (22S to 26S), water samples were taken in 39 oceanographic stations and images of MODIS Terra and Aqua sensors, toghether with hidrography, were employed to decribe the mesoscale oceanographic features.The total abundance of both size fractions, as well as the dominance of picoplankton, decreased as a function of distance from the coast. Autotrophic organisms were, predominantly, on average (102 cell.mL-1 to 104 cell.mL-1) one order of magnitude lower than the heterotrophic (103 cell.mL-1 to 105 cell.mL-1). The South Atlantic Central Water (SACW) and the plumes of Guanabara and Sepetiba bays (RJ) remained in the inner shelf favoring an increase in macronutrients concentration and reflecting changes in community structure by the increase of autotrophs contribution, especially in the central portion of the shelf, mainly ultraplankton at surface (21%) and in maximum chlorophyll depth (44%). The transport of coastal waters carried by a current from south caused the shelf eddy identified by water colour/chlorophyll images for the region of Ubatuba inner shelf (SP), where high concentrations of ammonium (0,28 M) and phosphate (9,64 M) near the depth of 50 m supported higher density of autotrophic ultraplankton (2.89 x 103 cells.mL-1) which exceeded the density of heterotrophs at the chlorophyll maximum (2.19 x 103 cells.mL-1). Our results highlighted a strong neritic-oceanic gradient in the distribution of these organisms. They also suggest the predominance of the heterotrophic metabolism in the majority of the oligotrophic waters of the shelf and slope between Rio de Janeiro and São Paulo, as well as the presence of an autotrophic nature in those regions influenced by mesoscale features, such as estuarine plumes and shelf eddies.
100

Interações ecológicas associadas a Ipomoea carnea subs. fistulosa (Martius e Choise) (convolvulaceae) em uma área de caatinga no Nordeste do Brasil

MARTINS, Joanny Kelly Silva dos Santos 21 July 2015 (has links)
Submitted by (ana.araujo@ufrpe.br) on 2016-08-23T12:05:53Z No. of bitstreams: 1 Joanny Kelly Silva dos Santos Martins.pdf: 1467107 bytes, checksum: 51dc871b39b7f000a36a8445217f21da (MD5) / Made available in DSpace on 2016-08-23T12:05:54Z (GMT). No. of bitstreams: 1 Joanny Kelly Silva dos Santos Martins.pdf: 1467107 bytes, checksum: 51dc871b39b7f000a36a8445217f21da (MD5) Previous issue date: 2015-07-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The objective of this study was to survey the richness and abundance of pollinators, herbivores, ants and other predators associated to Ipomoea carnea subs. fistulosa, addition to assessing the indirect effects of florivory and the influence of patrolling ants associated with extrafloral nectaries on pollinators. The study was conducted durig eight months (August/2014 – March/2015) at the Fazenda Tamanduá, municipality of Santa Terezinha, Paraíba state, Brazil. It was quantified the number of pollinator visits in flowers with and without patrolling ants and flowers with simulated florivory. The number of herbivores per inflorescence and the occurrence of florivory were recorded in an experiment conducted from 5 am to 5 pm. Arthropods were collected monthly to record the richness and abundance. The temporal variation of florivory and production of buds, flowers and fruits were recorded monthly. The results of the effect of the damage and the presence of floral ants showed that both cause a decrease in the total number of visits. This can be explained by the fact that the floral damage was the loss of important floral attributes. Additionally, bees can evaluate the pattern of flower symmetry distance and detect predators corroborating the hypothesis that predators such as ants, remove pollinators of plant-pollinator systems. These effects may be considered risky for Ipomoea carnea subs. fistulosa, since it is a self-incompatible species and depends on the activity of pollinators for its fertilization. The composition of the arthropod fauna associated with plant species under study was represented by five groups: Araneae, Coleoptera, Hymenoptera, Diptera and Hemiptera. The highest abundance of herbivores occurred in months with low rainfall. The florivory rates were high, and more severe in the dry season. The number of ants associated to extrafloral nectaries increased directly with the abundance of herbivores over months. The multitrophic system studied showed complex, featuring a high richness of associated arthropods and various guilds among the trophic levels. During the dry season in the caatinga, Ipomoea carnea subs. fistulosa is one of the few species that persist with leaves and flowers, this enables the populations of I. carnea constitute major indicator spots resources for present herbivores. This may have been one of the main causes for the abundance of herbivores and floral herbivory rate was higher in the months with less precipitation. Overall the data suggest that abundance of herbivores was related to the quality and availability of plant resources, reflecting on other trophic levels as in a bottom-up model of trophic cascade. / O objetivo deste trabalho foi realizar um levantamento da riqueza e abundância dos polinizadores, herbívoros, formigas e predadores de insetos associados a Ipomoea carnea subs. fistulosa, bem como avaliar os efeitos indiretos da florivoria e a influência do patrulhamento de formigas associadas aos nectários extraflorais sobre os polinizadores. Este trabalho foi realizado em oito meses de coleta (agosto de 2014 a março de 2015) na Fazenda Tamanduá, no município de Santa Terezinha, PB. Foi quantificado o numero de visitas de polinizadores em flores com e sem patrulhamento de formigas e em flores com florivoria simulada. O número de herbívoros por inflorescência e a ocorrência de florivoria foi registrado em um experimento realizado das 5h às 17h. Os artrópodes foram coletados mensalmente para registro da riqueza e abundância. E a variação temporal da florivoria e produção de botões, flores e frutos foi registrada mensalmente. Os resultados do efeito do dano floral e presença de formigas mostraram que ambos provocam decréscimo no número de visitas totais. Isso pode ser justificado pelo fato de que o dano floral consistiu na perda de atributos florais importantes. Adicionalmente abelhas podem avaliar o padrão de simetria da flor à distância e detectar predadores corroborando com a hipótese de que predadores, tal como formigas, retiram polinizadores dos sistemas planta-polinizador. Estes efeitos para Ipomoea carnea subs. fistulosa podem ser considerados de risco, uma vez que é um espécie autoincompatível e depende da atividade dos polinizadores para que a sua fecundação ocorra. A composição da fauna de artrópodes associados a espécie vegetal em estudo foi representada por cinco grupos: Araneae, Coleoptera, Hymenoptera, Diptera e Hemiptera. O sistema multitrófico estudado se mostrou complexo, apresentando uma grande riqueza de artrópodes associados e variadas guildas dentre os níveis tróficos. Durante a estação seca na caatinga Ipomoea carnea subs. fistulosa, é uma das poucas espécies que persistem com folhas e flores, fato que faz com que as populações de I. carnea constituam grandes manchas indicadoras de recursos para os herbívoros presentes. Esta pode ter sido uma das principais causas para que a abundância de herbívoros e taxa de herbivoria floral tenha sido mais alta nos meses com menor precipitação. De maneira geral os dados sugerem que abundância de herbívoros respondeu a qualidade e disponibilidade dos recursos vegetais, refletindo nos demais níveis tróficos como em um modelo bottom-up de cascata trófica.

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