O gerenciamento dos recursos hídricos em bacias de regiões semi-áridas requer a compatibilização da oferta crítica de água com a demanda. Este problema assume caráter especialmente relevante quando se trata de bacias com solos férteis, submetidas a demanda de água para irrigação. A bacia do rio Mosquito, afluente do Verde Grande, no norte de Minas Gerais se insere nesta problemática. A região, por suas características hidroclimáticas, econômicas e sociais é incluída no polígono das secas. Possui uma economia altamente dependente da agricultura que aproveita os solos geralmente férteis. O desenvolvimento não planejado da irrigação trouxe conflitos de uso que se constituem em um dos principais entraves ao desenvolvimento da bacia. Este trabalho descreve os estudos realizados visando a compatibilização da oferta da água com a demanda. No que tange à oferta de água o estudo foi orientado ao dimensionamento e operação de reservatórios de regularização. A limitação das disponibilidades hídricas levou à necessidade de se gerenciar demanda através de duas abordagens: limitando-a, através de um valor máximo de área irrigável, e administrando-a em anos extremamente secos através de esquemas de racionamentos. Um resultado interessante é que na maioria das vezes a necessidade de racionamento pode ser estabelecida no início da estação seca, permitindo teoricamente que os irrigantes dimensionem a área a ser irrigada nesta estação de acordo com as disponibilidades de água. A adoção desta sistemática requer, entretanto, a crição de uma estrutura organizacional e legal que é comentada e discutida. / Water resource management in · basins in semi-arid regions requires compatibilization between critical supply of water and demand. This problem is especially relevant when it involves basins with fertile soils, where there is a demand for irrigation water. This problem occurs in basin of the river Mosquito, a tributary of Verde Grande, in the north of the state of Minas Gerais. Due to its hydroclimatic, economic and social conditions, this region is part of the polygon of droughts. Its economy is highly dependent on agriculture which uses the generally fertile soils. Unplanned development of irrigation caused conflicts of use which are one of the main barriers to basin development. This work describes the studies performed to compatibilize water supply and demand. As regards water supply, the study was oriented toward the sizing and operation of regulation reservoirs. The limitation of water availability led to need of managing demand by means of rationing schemes. An interesting result is that, generally, the need for rationing can be determined at the beginning of the dry season, and theoretically allows the irrigators to size the area to be irrigated during this season, according to water available. The use of this system, however, requires setting up an organizational and legal structure which is examined and discussed.

Introdução: O estudo dos insetos em virtude da nocividade ou benefício que oferecem ao homem é objeto da entomologia aplicada. No Brasil, a incorporação da entomologia pela saúde pública vem ocorrendo de forma gradual até os dias de hoje. A vigilância entomológica surge como uma ferramenta que possibilita sistematizar informações sobre os insetos, com a finalidade de conhecer aspectos biológicos e ecológicos que permitam definir o papel vetorial, predizer o risco de exposição da população humana aos vetores e fornecer bases técnicas para ações de controle das espécies de interesse. Embora existam meios legais para tornar a Vigilância Entomológica uma prática contínua e abrangente, essa ainda não é uma realidade no Rio Grande do Sul. Objetivo: Demonstrar a importância da entomologia em saúde pública, através das práticas de Vigilância Entomológica de mosquitos (Diptera, Culicidae), vinculadas à rotina da Vigilância Ambiental em Saúde. Métodos: Entre dezembro de 2006 e dezembro de 2008 foram realizados estudos mensais, abordando aspectos ecológicos da fauna em uma área de Mata Atlântica do litoral norte do Estado, empregando armadilhas CDC e aspirador de Nasci. Em novembro de 2008, no noroeste, foram realizadas investigações entomológicas em áreas com circulação de vírus da febre amarela, utilizando rede entomológica associada a aspirador tipo frasco e, em julho de 2006, ações de monitoramento do vírus do Nilo Ocidental em refúgio de aves migratórias no sul do Estado, com uso de aspirador de Nasci. Resultados: O trabalho possibilitou detectar 23 novos registros de mosquitos para o Rio Grande do Sul. As coletas continuadas mostraram uma distribuição sazonal das espécies, sendo o período de outubro a maio o mais indicado para atividades de levantamento e monitoramento da fauna. O papel vetorial de Haemagogus leucocelaenus foi comprovado já que o vírus da febre amarela foi novamente detectado nessa espécie. Outra importante contribuição foi o primeiro isolamento do vírus da febre amarela em Aedes serratus, sugerindo o papel dessa espécie como 5 vetor secundário do vírus. Conclusões: A Vigilância Entomológica forneceu informações e indicadores que ampliam as perspectivas sobre a capacidade e competência vetorial de algumas espécies de mosquitos do Rio Grande do Sul, evidenciando a importância dessa ferramenta / Introduction: The study of insects, due to the damage or benefit they give to humans, is an object of applied entomology. In Brazil, the incorporation of entomology by public health has been occurring gradually until today. The Entomological Surveillance appears as a tool that provides the organization of information about the insects, aiming to know biological and ecological aspects that allow the definition of the role of vectors, the prediction of the risk of exposure of the human population to the vectors, and the provision of technical foundation in the control of key species. Although there are legal ways to turn the Entomological Surveillance in a continuous and broad practice, this is not real in Rio Grande do Sul. Objective: To demonstrate the importance of the entomology in public health through the practice of Entomological Surveillance of mosquitoes (Diptera, Culicidae), linked to the routine of the Health Environmental Surveillance. Methods: Between December 2006 and December 2008 systematic studies were carried out and focused on ecological aspects of the fauna in an Atlantic Forest area on the north coast of the state, using CDC traps and Nasci vacuum. In November 2008, in the northwestern region, entomological investigations were performed in areas with circulation of the yellow fever virus, using an entomological net associated with a bottle-type vacuum. In July 2006, monitoring of the West Nile virus in a refuge of migratory birds was carried out using a Nasci vacuum. Results: The study promoted the detection of 23 new records of mosquitoes for Rio Grande do Sul State. Systematic sampling demonstrated a seasonal distribution of the species, with the period between October and May adequate to activities related to fauna surveying and monitoring. The role of Haemagogus leucocelaenus as a vector was demonstrated since the yellow fever virus was again detected in this species. Another important contribution was the discovery of the first isolate of the virus in Aedes serratus, suggesting a role of this 7 species as secondary vector of the virus. Conclusions: The Entomological Surveillance gave information and indicators that broadened perspectives on the vector capacity and competency of determined mosquito species in Rio Grande do Sul, highlighting the importance of this tool

DeKalb and Fulton Counties, which share the metropolitan Atlanta area, have seen an increase in West Nile infected vector mosquitoes; the increase is associated with close proximity to combined sewer overflow facilities. Despite completion of the remediation system in 2008, the mosquito population testing positive for West Nile virus has increased each year from 2010 through 2012. Guided by the Geographical Information System framework and using spatial analysis and regression analyses, this study described and quantified the relationship between sewer system overflows and amplification of vector mosquitoes; an additional goal was to investigate their proximity to human cases of West Nile VIrus (WNV) infections. Comparing the prominence of all WNV vectors revealed how different mosquito species occupy the area. The Culex species was not detected in adult surveillance in 2012; however, the infection rate of mosquito pools increased by 15% and the human infection more than doubled. The influence of sewer system overflows became pronounced when this study analysis also identified that a proportion of West Nile-virus positive mosquito pools was significantly higher in approximately 58% of trap sites within 1 km of sewer overflow events and 30% over 1 km distance from sewer overflow events. Thus, the research contributes to shared information both in support of previous findings and considering novel sources that contribute to the proliferation of WNV. This research can help reduce the rate of WNV infection and decrease the resources needed to protect the public.

Runnelling is a popular method of physical habitat modification employed on saltmarshes to control pest mosquito populations. The runnelling method involves linking the tidal source to isolated mosquito breeding pools via shallow channels that enable slow water movement of low amplitude tides. Increased tidal flushing inhibits mosquito development. The range of organisms which inhabit saltmarsh are likely to be influenced by altered tidal conditions as they exhibit specific physicochemical requirements for feeding, burrowing or growth. The dynamic nature of saltmarsh may mean that changes to the tidal frequency of a particular region of the saltmarsh promotes extension of marine-like conditions. Because runnels increase the frequency of flooding tidal events in specific regions of the saltmarsh this study predicted that resulting changes would be evident in the physical conditions of saltmarsh substrate, in the transport of buoyant vegetative propagules, in the population characteristics of surface grazing snails and in the density and aperture of crab burrows after flooding and non-flooding tidal events. The physical impacts of runnelling were determined at three marshes which appeared similar in terms of topography, substrate and tidal conditions. Soil water content and consolidation were measured using two sampling protocols: a) comparisons between modified and unmodified shores; and, b) comparisons with increasing lateral distance across the shore from the runnel edge. At one marsh, moisture levels were significantly higher at runnelled than at unrunnelled sites when tides filled the runnels, but this pattern was not found at the other marshes. Soil consolidation was greater at higher shore heights, but was not different between runnelled and unrunnelled shores. Measurements at different lateral distances from runnels demonstrated higher moisture levels and lower consolidation up to 5 m from the edge but not further away. Groups of marked Avicennia marina propagules were released at the three runnelled saltmarshes during flooding and non-flooding tidal events. Groups of propagules released within 10 m of a runnel were always transported significantly further from the starting position and further up the saltmarsh shore after both flooding and non-flooding tides than any other groups. In addition, the pattern of stranding on saltmarsh for significantly different groups was closely associated with the path of runnel construction so that propagules were located either in the runnel or in depressions linked to the runnel that had been isolated mosquito-breeding pools prior to runnelling. It is likely that altered physical soil conditions significantly affected the distribution and size structures of Salinator solida and Ophicardelus spp. snails recorded at the three saltmarshes. The interaction of tidal period and the presence of a runnel contributed to patterns with significant differences between runnelled and unrunnelled regions of the marsh. Generally, the runnel population of snails exhibited flood-like features even during non-flood periods. The distribution and size classes of snails did not differ with lateral distance from runnels. The burrow characteristics of the crab Helograpsus haswellianus were compared to increase the accuracy of estimating abundance from burrow counts. Including only those burrows which were obviously maintained by resident crabs significantly increased the confidence limits of estimating crab abundance using only burrow density counts. This method was applied to runnelled and unrunnelled sites to assess any changes in the density of burrows associated with the presence of runnels. Again, it is likely that physical soil conditions resulting from increased tidal frequency at the runnel did influence crab burrowing with fewer small burrows being found at the runnelled site, low on the shore. In addition, mid- and large-sized burrows tended to dominate close to the runnel edge. Site-specific soil characteristics may help to explain the lack of continuity in patterns associated with runnel effects on non-target saltmarsh resources. While the runnel may increase the soil water content of clayey substrates at some sites it could also result in de-watering of porous sandy soils at other shores. This was evident in the structure of the snail population and distribution of crab burrows which appeared to reflect altered soil physical characteristics associated with the runnel. Runnelling does affect non-target organisms in saltmarsh. However, the scale of impact was usually locally restricted (< 10 m from the runnel edge). The fact that patterns were not recorded at all sites suggests that the influence of runnels is variable and limited by substrate and some biological conditions. Given the efficiency and popularity of runnelling as a physical control method for reducing pest vector mosquito habitat, this study found no evidence to suggest that its use should be discontinued on any ecological basis measured.

Giralang Pond was a water body, with little emergent or submerged vegetation, designed to trap fine sediment and buffer input of rising water to Ginninderra Wetland downstream. Ginninderra Wetland was designed to retain and use sediment nutrients and other potential hazardous materials in urban run-off. Water in the Wetland was more turbid and had lower magnesium concentration, redox potentials and dissolved oxygen concentration than did Giralang Pond. Water temperature was a minimum of 4 °C in the winter and reached a summer maximum of 30 °C Giralang Pond had more organisms but fewer taxa than Ginninderra Wetland. The greatest abundance in the pond resulted principally from high numbers of two numerically dominant species Calamoecia sp. and Micronecta sp.. More organisms were found in vegetated habitats of Ginninderra Wetland than open water habitats. The number of invertebrates and the number of taxa found in Typha domingensis did not differ significantly from similar estimates for Schoenplectus validus, Gambusia qffinis was the dominant predator in both water bodies. On one occasion, G. qffinis reached population densities of 35 individuals per m-2 . G. qffinis was five times more abundant in Gininnderra Wetland than in Giralang Pond and also showed a preference for vegetated areas. G. qffinis over-grazed it's prey on several occasions. G. qffinis, invertebrate predators and prey followed a pattern of a community in a stable predator-prey cycle. Prey in early spring increased population numbers and then decreased when G. qffinis and other predators increased their numbers. The pattern was further strengthened by occurring in both areas of open water and vegetated habitat types.

This thesis undertakes analysis of members of the neighborhood anti-mosquito volunteer team which was co-established by the Kaohsiung City Gushan District Office and the Department of Health and finds members of the team have, for the most part, not sufficiently encouraged others to join or participate in dengue fever vector mosquito prevention. In addition, these team members lack proper concepts concerning individual prevention of dengue fever carrying mosquitoes. This study therefore advises anti-mosquito volunteers that anti-mosquito teams must emphasize education concerning environmental behavior, as well as increase public awareness of vector mosquito prevention and measures for individual prevention. In order to make dengue fever vector prevention more effective, it is necessary to start with environmental behavior. In addition to advocating for proper environmental behavior, education and information dissemination concerning environmental behavior must be strengthened so as to increase the effectiveness of the anti-mosquito volunteer workers in dengue fever vector prevention and allow them to attain better results. The possibility of a dengue fever epidemic is an annual threat to the health of the citizens in Southern Taiwan¡¦s Kaohsiung City. The most important tasks in creating a new precedent with respect to mosquito control are to determine how to utilize community and neighborhood anti-mosquito volunteer team resources, to increase efforts to instruct neighborhood citizens to rid their home environments of objects which can retain water, to rid communities of breading sites, to improve environmental sanitary conditions, and to continue advocating neighborhood environmental health works in order to lower vector density for dengue fever and reach the goal of having cleaner and healthier home environments. Needless to say, this type of policy requires the selfless contributions and enthusiastic participation of the community¡¦s citizens. With this in mind, we must ask whether assistance the government provides in can facilitate the effectiveness of anti-mosquito volunteer teams. In addition, we should inquire into what impressions anti-mosquito volunteers have concerning dengue fever vector prevention. This thesis examines the extent to which anti-mosquito volunteer team members¡¦ cognition of environmental literacy influences the effectiveness of dengue fever vector prevention through an analysis which examines the interaction between anti-mosquito volunteer team attributes, members¡¦ environmental literacy, and dengue fever vector prevention results. This study uses the questionnaire survey method and various statistics in compiling data and utilizes various statistical techniques to understand the relationship between these factors, find a clear policy direction, and make this work less arduous and more productive.

In the yellow fever mosquito, Aedes aegypti (L.), hemolymph-circulating diuretic hormones act upon the renal organs (Malpighian tubules) to regulate primary urine composition and secretion rate; however, the molecular endocrine mechanisms underlying rapid water elimination upon adult eclosion and blood feeding are not fully understood. Bioinformatic analysis of the current Aedes aegypti genome assembly reveals only a single predicted corticotropin releasing factor (CRF)-like diuretic hormone 44 (DH44) gene, but two DH44 receptor genes. The tissue expression profiles of the DH44 receptor(s), and specifically the identity of the DH44 receptor(s) in the Malpighian tubule, are undetermined in any mosquito species. This dissertation shows that Vectorbase gene ID AAEL008292 encodes a DH44 receptor (AaegGPRdih1) transcribed in Malpighian tubules. Sequence analysis and transcript localization indicate that AaegGPRdih1 is the co-ortholog of the Drosophila melanogaster DH44 receptor (CG12370-PA). The presence of conserved amino acid residues between AaegGPRdih1 and vertebrate CRF receptors suggests this mosquito receptor modulates multiple G protein-dependent intracellular signaling pathways. Quantitative PCR analysis of a time course of Malpighian tubule cDNA reveals AaegGPRdih1 abundance increases paralleling periods of observed urination. This suggests that target tissue receptor biology is linked to the known periods of release of diuretic hormones from the nervous system, pointing to a common up-stream regulatory mechanism. Higher relative abundance of AaegGPRdih1 transcript in female Malpighian tubules 24 hours after blood feeding suggests a role for AaegGPRdih1 in the excretion of nitrogen waste. RNA-mediated silencing to establish the significance of AaegGPRdih1 to mosquito Malpighian tubule physiology was inconclusive.

Malaria incidence in the province of KwaZulu-Natal is influenced by seasonal climatic variations, drug and insecticide resistance, and population mobility within the region. Current control methods are directed at the malaria vector, the Anopheles arabiensis mosquito, through indoor residual spraying. Control of the dominant malaria parasite, Plasmodium falciparum, is done by treatmenting the symptomatic and asymptomatic parasite carriers with prophylactic medications of. A ceiling of effectiveness with current control efforts have been reached, necessitating the search for supplementary methods. The study area is located in the Ingwavuma District of northern of KwaZulu-Natal which adjoins the Mozambique border to the north, and includes the malaria areas of Ndumu and Makanisdrift. Homestead location coordinates were obtained with Global Positioning System (GPS) receivers and linked to malaria case records through homestead numbers which have been allocated to all homes in the area. The study includes the cases reported during 1993 and 1994 as this was the only data available when the project commenced in 1995. A geographic information system was used to undertake the spatial analysis to test the hypothesis that the malaria vector, Anopheles arabiensis, is localised to certain breeding sites during the winter months in northern KwaZulu-Natal. Identification of these winter 'seed point' breeding sites from which the onset of transmission spreads during the following malaria season, will allow them to be targeted for winter larval control measures. This will contribute to limiting the distribution and lowering the levels of malaria intensity in the region as a whole. The analysis also provided evidence of the maximum likely flight distance of the female mosquito given an adequate host supply in close proximity, thereby identifying those areas requiring additional prevention and control activities. Understanding the local epidemiology of the disease was necessary to determine which monthly malaria cases to include in order to identify the winter breeding sites, due to seasonal variations in the length of the mosquitoes life cycle. Medical geography, as a sub-discipline of geography, combines investigating spatial patterns with the epidemiological principles of medicine and zoology through scientific methods. It is traditionally divided into two approaches, the first being the geography of disease, under which this research falls, and the second being the geography of health care. The integration of the two disciplines allowed the results of the analysis to be presented in maps, graphs and tables in order to describe, interpret, test and explain possible associations between the location of the potential breeding sites and the homesteads at which the malaria cases were reported. The potential breeding sites consisted of the perennial pans, non-perennial pans and dams. Zones were created in the GIS at one kilometre intervals from these sites up to a distance of four kilometres, and the number of cases within each zone determined and corrected for the population at risk per 1000 people for comparative purposes. This spatial analysis was followed by the statistical analysis of the results to verify the findings. The results of the spatial and statistical analysis indicated that the perennial pans were used as the winter 'seed point' breeding sites, and that the maximum likely flight distance of the female mosquito, given an adequate host supply in close proximity, is 4 kilometres. The results will be made available to the local malaria research and control community who will assess the feasibility of implementing supplementary control measures. / Thesis (M.Sc.)-University of Natal, Durban, 2001.

The evolution of the blood feeding adaptation has required precise coordination of multiple physiological processes in the insect, such as reproduction, behavior, digestion and diuresis. These processes are under careful synchronous hormonal control. For rapid excretion, multiple diuretic hormones are known. Although originally described based on their ability to stimulate hindgut contractions, the Aedes kinins have been shown to stimulate fluid secretion in female mosquitoes of Aedes aegypti. Aedes kinins are leucokinin-like neuropeptides released from neurosecretory cells in the brain and abdominal ganglia. They act by binding to the Aedes kinin receptor, a G proteincoupled receptor (GPCR). The Aedes kinin receptor has been cloned, sequenced, functionally characterized, and immunolocalized to stellate cells in the Malpighian tubules of Ae. aegypti. In addition to their myotropic and diuretic roles, leucokinin-like peptides and/or their receptors have been also been discovered in the nervous, digestive, and reproductive systems of other arthropod species. Therefore, the Aedes kinins have the potential to function in several simultaneous physiological processes that are stimulated by blood feeding. This thesis aims to understand better their role in the whole mosquito by investigating the Aedes kinin receptor's global expression as well as its in vivo contribution to post-prandial diuresis. Presence of the Aedes kinin receptor was investigated in the head, posterior midgut (stomach), hindgut, ovaries, and Malpighian tubules of both non blood-fed and blood-fed females by western blot using anti-receptor antibodies. The receptor was then immunolocalized in the posterior midgut and rectum. Finally, RNAi was employed to knock down kinin receptor expression, followed by measurement of in vivo urine excretion post blood feeding in a precision humidity chamber. Transcript and protein knockdown were confirmed by qPCR and immunohistochemistry, respectively. Results indicate widespread expression of the Aedes kinin receptor protein in organs novel for hematophagous insects and demonstrate the receptor's fundamental role in rapid diuresis. These findings strongly point to the Aedes kinins as integrative signaling molecules that could coordinate multiple physiological systems. The Aedes kinins could therefore have contributed to the success of the blood feeding adapation in mosquitoes.

The role of odorant binding proteins in the olfaction of mosquitoes, the primary mechanism of human host recognition, has been an important focus of biological research in the field of infectious disease transmission by these insects. This thesis provides an in depth knowledge of these proteins in three mosquito species Anopheles gambiae, Aedes aegypti and Culex quinquefasciatus. A large scale analysis on these genomes has been carried out towards the identification of the odorant binding proteins in the mosquito genomes. Identification of many new OBP members, in particular in the Aedes aegypti and Culex quinquefasciatus species, and an extensive phylogenetic analysis presenting a novel classification of the OBP subfamilies of these mosquito species has been proposed. This results further demonstrates the extraordinary multiplicity and diversity of the OBP gene repertoire in these three mosquito genomes and highlights the striking sequence features that are nevertheless highly conserved across all mosquito OBPs. Owing to the availability of homologous structures from mosquitoes or related species, the 3D structure modelling of all the Classic OBPs from the three genomes (representing in total 137 structures) has been performed. This was completed by large scale docking studies on these structures by screening a large set of compounds that are known to be mosquito attractants or repellents. These provide many exciting new insights into the structural and functional aspects towards understanding the efficacy of some repellents and of some attractants from human emanations. Through molecular dynamics simulation, the structural changes observed in an OBP bounded to an odorant when pH conditions are modified were characterized and the probable mechanism of ligand binding and release is presented. This work provides the first insights to many of the long awaited questions on the genomic, structural and functional characterization of mosquito OBPs and can be viewed as a reliable starting point for further experimental research focussed on these aspects.