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Ana Cristina R Vitta - One of the best experts on this subject based on the ideXlab platform.
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the metasternal and brindley s glands of triatoma brasiliensis neiva hemiptera reduviidae
Neotropical Entomology, 2009Co-Authors: Ana Cristina R Vitta, Eraldo R Lima, Jose Eduardo Serrao, Evaldo F VillelaAbstract:Triatoma brasiliensis Neiva is the most important vector of the Chagas' disease in the Semiarid Zones of North-eastern Brazil. Adult bugs have two main pairs of exocrine glands, the metasternal and the Brindley's glands, which release volatiles possibly with defense, alarm and/or mating functions. To date, anatomical and histological studies of the metasternal and the Brindley's glands in the genus Triatoma are scarce and, considering the relevance of these exocrine glands, the present work aimed at studying their morphology in T. brasiliensis. The metasternal and the Brindley's glands of T. brasiliensis consist of glandular units similar to those described for Rhodnius prolixus Stal and Panstrongylus megistus Burmeister, comprising a secretory apparatus, saccule and collector duct.
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systematics morphology and physiology the metasternal and brindley s glands of triatoma brasiliensis neiva hemiptera reduviidae
2009Co-Authors: Ana Cristina R Vitta, Eraldo R Lima, Jose Eduardo Serrao, Evaldo F VilelaAbstract:Triatoma brasiliensis Neiva is the most important vector of the Chagas’ disease in the Semiarid Zones of Northeastern Brazil. Adult bugs have two main pairs of exocrine glands, the metasternal and the Brindley’s glands, which release volatiles possibly with defense, alarm and/or mating
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the use of aggregation signals by triatoma brasiliensis heteroptera reduviidae
Acta Tropica, 2007Co-Authors: Ana Cristina R Vitta, Lileia Diotaiuti, T R P Mota, Marcelo G LorenzoAbstract:Triatoma brasiliensis is considered the main vector of Chagas disease in the Semiarid Zones of North-eastern Brazil. In this work, we describe the spatial pattern of defecation in T. brasiliensis and the spatial relationship of faeces with the shelters of these bugs. Afterwards, we analyse the attraction response of T. brasiliensis larvae to potential odour cues present in their dry faeces, to substances present in their cuticule (footprints) and to the dry faeces of Triatoma pseudomaculata. We show that faecal spots are deposited in a larger density inside the shelter than in the remaining area available for the bugs. T. brasiliensis larvae were significantly attracted towards their own faeces, and also to those of T. pseudomaculata. In contrast to other triatomine species, footprints did not promote attraction in T. brasiliensis. The potential use of communication signals of T. brasiliensis as tools for helping control this species is discussed.
F. Francés - One of the best experts on this subject based on the ideXlab platform.
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A conceptual dynamic vegetation-soil model for arid and Semiarid Zones
Hydrology and Earth System Sciences Discussions, 2007Co-Authors: D. I. Quevedo, F. FrancésAbstract:Plant ecosystems in arid and Semiarid Zones show high complexity from the point of view of water resources, since they depend on water availability to carry out their vital processes. In these climates, water stress is the main factor controlling vegetation development. The available water in the system results from a water balance where the soil, vegetation and the atmosphere are the key issues; but it is the vegetation which modulates (to a great extent) the total balance of water and the mechanisms of the feedback between soil and atmosphere, being the knowledge about soil moisture quite relevant for assessing available water and, as a consequence, for growth and plants maintenance and the final water balance in the system. A conceptual dynamic vegetation-soil model (CDVSM) for arid and Semiarid Zones was developed. This model based in a tank type conceptualization represents in a suitable way, for Mediterranean climate, the vegetation responses to soil moisture fluctuations. Two tanks interconnected were considered using the water balance equation and the appropriate dynamic equation for all considered fluxes. The first one corresponds to the interception process done by the vegetation. The second one models the upper soil moisture determination. In this tank parameters are based on soil and vegetation properties. The transpiration of the vegetation is a function of the soil moisture, the vegetation type and the biomass. Once all water state variables are evaluated at each time step, the modifications in the biomass are made as a function of transpiration rate and water stress. Simulations for monoculture of Quercus Coccifera L. were carried out. Results shows that CDVSM is able to represent the vegetation dynamic, reflecting how the monoculture is stabilized around 0.7 of relative biomass, with adaptation to the soil moisture fluctuations in the long term. The model shows the vegetation adaptation to the variability of the climatic conditions, demonstrating how either in the presence or shortage of water, the vegetation regulates its biomass as well as its rate of transpiration trying to minimize the total water stress.
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a conceptual dynamic vegetation soil model for arid and Semiarid Zones
Hydrology and Earth System Sciences, 2007Co-Authors: D. I. Quevedo, F. FrancésAbstract:Plant ecosystems in arid and Semiarid climates show high complexity, since they depend on water availabil- ity to carry out their vital processes. In these climates, water stress is the main factor controlling vegetation development and its dynamic evolution. The available water-soil content results from the water bal- ance in the system, where the key issues are the soil, the veg- etation and the atmosphere. However, it is the vegetation, which modulates, to a great extent, the water fluxes and the feedback mechanisms between soil and atmosphere. Thus, soil moisture content is most relevant for plant growth main- tenance and final water balance assessment. A conceptual dynamic vegetation-soil model (called HO- RAS) for arid and semi-arid Zones has been developed. This conceptual model, based on a series of connected tanks, rep- resents in a way suitable for a Mediterranean climate, the vegetation response to soil moisture fluctuations and the ac- tual leaf biomass influence on soil water availability and evapotranspiration. Two tanks were considered using at each of them the water balance and the appropriate dynamic equa- tion for all considered fluxes. The first one corresponds to the interception process, whereas the second one models the evolution of moisture by the upper soil. The model parame- ters were based on soil and vegetation properties, but reduced their numbers. Simulations for dominant species, Quercus coccifera L., were carried out to calibrate and validate the model. Our re- sults show that HORAS succeeded in representing the vege- tation dynamics and, on the one hand, reflects how following a fire this monoculture stabilizes after 9 years. On the other hand, the model shows the adaptation of the vegetation to the variability of climatic and soil conditions, demonstrating that in the presence or shortage of water, the vegetation regulates
D. I. Quevedo - One of the best experts on this subject based on the ideXlab platform.
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A conceptual dynamic vegetation-soil model for arid and Semiarid Zones
Hydrology and Earth System Sciences Discussions, 2007Co-Authors: D. I. Quevedo, F. FrancésAbstract:Plant ecosystems in arid and Semiarid Zones show high complexity from the point of view of water resources, since they depend on water availability to carry out their vital processes. In these climates, water stress is the main factor controlling vegetation development. The available water in the system results from a water balance where the soil, vegetation and the atmosphere are the key issues; but it is the vegetation which modulates (to a great extent) the total balance of water and the mechanisms of the feedback between soil and atmosphere, being the knowledge about soil moisture quite relevant for assessing available water and, as a consequence, for growth and plants maintenance and the final water balance in the system. A conceptual dynamic vegetation-soil model (CDVSM) for arid and Semiarid Zones was developed. This model based in a tank type conceptualization represents in a suitable way, for Mediterranean climate, the vegetation responses to soil moisture fluctuations. Two tanks interconnected were considered using the water balance equation and the appropriate dynamic equation for all considered fluxes. The first one corresponds to the interception process done by the vegetation. The second one models the upper soil moisture determination. In this tank parameters are based on soil and vegetation properties. The transpiration of the vegetation is a function of the soil moisture, the vegetation type and the biomass. Once all water state variables are evaluated at each time step, the modifications in the biomass are made as a function of transpiration rate and water stress. Simulations for monoculture of Quercus Coccifera L. were carried out. Results shows that CDVSM is able to represent the vegetation dynamic, reflecting how the monoculture is stabilized around 0.7 of relative biomass, with adaptation to the soil moisture fluctuations in the long term. The model shows the vegetation adaptation to the variability of the climatic conditions, demonstrating how either in the presence or shortage of water, the vegetation regulates its biomass as well as its rate of transpiration trying to minimize the total water stress.
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a conceptual dynamic vegetation soil model for arid and Semiarid Zones
Hydrology and Earth System Sciences, 2007Co-Authors: D. I. Quevedo, F. FrancésAbstract:Plant ecosystems in arid and Semiarid climates show high complexity, since they depend on water availabil- ity to carry out their vital processes. In these climates, water stress is the main factor controlling vegetation development and its dynamic evolution. The available water-soil content results from the water bal- ance in the system, where the key issues are the soil, the veg- etation and the atmosphere. However, it is the vegetation, which modulates, to a great extent, the water fluxes and the feedback mechanisms between soil and atmosphere. Thus, soil moisture content is most relevant for plant growth main- tenance and final water balance assessment. A conceptual dynamic vegetation-soil model (called HO- RAS) for arid and semi-arid Zones has been developed. This conceptual model, based on a series of connected tanks, rep- resents in a way suitable for a Mediterranean climate, the vegetation response to soil moisture fluctuations and the ac- tual leaf biomass influence on soil water availability and evapotranspiration. Two tanks were considered using at each of them the water balance and the appropriate dynamic equa- tion for all considered fluxes. The first one corresponds to the interception process, whereas the second one models the evolution of moisture by the upper soil. The model parame- ters were based on soil and vegetation properties, but reduced their numbers. Simulations for dominant species, Quercus coccifera L., were carried out to calibrate and validate the model. Our re- sults show that HORAS succeeded in representing the vege- tation dynamics and, on the one hand, reflects how following a fire this monoculture stabilizes after 9 years. On the other hand, the model shows the adaptation of the vegetation to the variability of climatic and soil conditions, demonstrating that in the presence or shortage of water, the vegetation regulates
Lileia Diotaiuti - One of the best experts on this subject based on the ideXlab platform.
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feeding performance of triatoma brasiliensis hemiptera reduviidae on habitual hosts thrichomys laurentius rodentia echimyidae and humans
Vector-borne and Zoonotic Diseases, 2011Co-Authors: Alessandra A Guarneri, Lileia Diotaiuti, Nelder F Gontijo, Ricardo N Araujo, Marcos H PereiraAbstract:Abstract Triatoma brasiliensis is an important vector of Trypanosoma cruzi in the Semiarid Zones of Northeastern Brazil where it is commonly found in human dwellings, peridomiciliary areas, and the wild environments. To better understand features that may be influencing the interaction of T. brasiliensis with its hosts, in the present work we compared the feeding performance of sylvatic and domestic populations of T. brasiliensis on humans and on Thrichomys laurentius, a wild rodent found in the natural ecotopes of T. brasiliensis. The analyses were performed using the electronic monitoring of the cibarial pump. The blood sources considerably affected the feeding parameters. Insects fed on T. laurentius had lower ingestion rate, gained less weight, had longer interruption time, remained less time in contact with the host, and had the contractions of the pump in a lower frequency during the feeding process in comparison to insects fed on humans. These results indicate that humans are better blood sources f...
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the use of aggregation signals by triatoma brasiliensis heteroptera reduviidae
Acta Tropica, 2007Co-Authors: Ana Cristina R Vitta, Lileia Diotaiuti, T R P Mota, Marcelo G LorenzoAbstract:Triatoma brasiliensis is considered the main vector of Chagas disease in the Semiarid Zones of North-eastern Brazil. In this work, we describe the spatial pattern of defecation in T. brasiliensis and the spatial relationship of faeces with the shelters of these bugs. Afterwards, we analyse the attraction response of T. brasiliensis larvae to potential odour cues present in their dry faeces, to substances present in their cuticule (footprints) and to the dry faeces of Triatoma pseudomaculata. We show that faecal spots are deposited in a larger density inside the shelter than in the remaining area available for the bugs. T. brasiliensis larvae were significantly attracted towards their own faeces, and also to those of T. pseudomaculata. In contrast to other triatomine species, footprints did not promote attraction in T. brasiliensis. The potential use of communication signals of T. brasiliensis as tools for helping control this species is discussed.
Marcelo G Lorenzo - One of the best experts on this subject based on the ideXlab platform.
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the use of aggregation signals by triatoma brasiliensis heteroptera reduviidae
Acta Tropica, 2007Co-Authors: Ana Cristina R Vitta, Lileia Diotaiuti, T R P Mota, Marcelo G LorenzoAbstract:Triatoma brasiliensis is considered the main vector of Chagas disease in the Semiarid Zones of North-eastern Brazil. In this work, we describe the spatial pattern of defecation in T. brasiliensis and the spatial relationship of faeces with the shelters of these bugs. Afterwards, we analyse the attraction response of T. brasiliensis larvae to potential odour cues present in their dry faeces, to substances present in their cuticule (footprints) and to the dry faeces of Triatoma pseudomaculata. We show that faecal spots are deposited in a larger density inside the shelter than in the remaining area available for the bugs. T. brasiliensis larvae were significantly attracted towards their own faeces, and also to those of T. pseudomaculata. In contrast to other triatomine species, footprints did not promote attraction in T. brasiliensis. The potential use of communication signals of T. brasiliensis as tools for helping control this species is discussed.
