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Sample records for american sand flies

  1. Habitat analysis of North American sand flies near veterans returning from leishmania-endemic war zones

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    Keep Lisa

    2008-12-01

    Full Text Available Abstract Background Nearly 1300 cases of leishmaniasis have been identified in American military personnel deployed to Iraq and Afghanistan. The symptoms of this disease can range from a mild, self-limiting cutaneous infection to a deadly visceral infection and are not prevented by chemoprophylaxis or immunization. Effective treatments, however, are available. The disease-causing parasite is spread through the bite of the female sand fly. Although the disease occurs in both the Old World and the New World, the parasite species differ between the hemispheres. The large number of cases in military veterans has caused some concern that Old World, temperate-adapted parasite species could be introduced into the native sand fly populations of American military facilities where veterans of the current conflicts return following their deployments. This paper reports part of a larger study to analyze the risk of such an accidental importation. Four potential habitats on two large Army facilities in the Southeast United States were surveyed to determine relative sand fly density. The National Land Cover Map was used to provide sand fly density prediction maps by habitat. Results Sand fly density was significantly higher in deciduous forest and even higher at the interface between forest and open grassland. The evergreen forest and agricultural fields supported very low densities. On Fort Campbell, KY, the percentage of land covered by suitable habitat was very high. A sand fly density prediction map identified large tracts of land where infected individuals would be at higher risk of exposure to sand fly bites, resulting in an increased risk of introducing the parasite to a native insect population. On Fort Bragg, NC, however, commercial farming of long leaf pine reduced the percentage of the land covered in vegetation suitable for the support of sand flies. The risk of introducing an exotic Leishmania spp. on Fort Bragg, therefore, is considered to be

  2. List of descriptions and other taxonomic proposals on american sand flies (Diptera, Psychodidae, Phlebotominae: 1975-1993

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    Carlos Brisóla Marcondes

    1995-01-01

    Full Text Available A check-list of new species, descriptions of other sex of previously described species, redescriptions, proposals of synonymy, and new status for species previously in synonymy or described as subspecies for american sand flies (Diptera, Psychodidae, Phlebotominae, for the period 1975-1993, and not included in the revision of Martins el at. (1978, are presented.

  3. Phlebotomine sand flies in Porteirinha, an area of American visceral leishmaniasis transmission in the State of Minas Gerais, Brazil

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    Ricardo Andrade Barata

    2004-08-01

    Full Text Available A study of the phlebotomine sand fly fauna was carried out in an endemic area of American visceral leishmaniasis (AVL in the municipality of Porteirinha, in the Brazilian state of Minas Gerais. Captures were performed with CDC light traps in 7 districts, 5 days per month, during 2 consecutive years (January 2000 to December 2001. A total of 3240 sand flies were captured and identified. Sixteen species were found, among which 15 belonged to the genus Lutzomyia and one to the genus Brumptomyia. Lutzomyia longipalpis, a proven vector of AVL, was the predominant species (71.85% throughout the time period. The interference of climatic factors (temperature, humidity, and rainfall over the populational dynamics of the sand flies was determined. Statistical analysis of the data showed a significant correlation among the number of phlebotomine sand flies collected, rainfall, and humidity, whereas the effect of temperature was negligible, in that particular region. The amount of collected phlebotomine, the number of human cases, and the prevalence of canine AVL in the districts of Porteirinha are discussed.

  4. Host preferences of the sand fly Lutzomyia longipalpis at an endemic focus of American visceral leishmaniasis in Colombia.

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    Morrison, A C; Ferro, C; Tesh, R B

    1993-07-01

    Blood meals from 579 Lutzomyia longipalpis (Diptera:Psychodidae), collected in an endemic focus of American visceral leishmaniasis in Colombia, were identified by precipitin test. Sand fly collections were made during a 16-month period from the inside walls of two houses, a pigpen, and rock crevices in a small community (El Callejon) within the endemic area. Feeding patterns of the sand flies varied with locality and date of collection. Overall, bovine feedings predominated, but feedings were also recorded on pigs, equines, humans, dogs, opossums, birds, and reptiles. Calculation of the forage ratios for each host species indicated that cows and pigs were the preferred hosts of Lu. longipalpis in El Callejon. Results of this study suggest that Lu. longipalpis is an opportunistic feeder and is not highly anthropophilic nor strongly attracted to dogs.

  5. Current and future niche of North and Central American sand flies (Diptera: psychodidae) in climate change scenarios.

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    Moo-Llanes, David; Ibarra-Cerdeña, Carlos N; Rebollar-Téllez, Eduardo A; Ibáñez-Bernal, Sergio; González, Camila; Ramsey, Janine M

    2013-01-01

    Ecological niche models are useful tools to infer potential spatial and temporal distributions in vector species and to measure epidemiological risk for infectious diseases such as the Leishmaniases. The ecological niche of 28 North and Central American sand fly species, including those with epidemiological relevance, can be used to analyze the vector's ecology and its association with transmission risk, and plan integrated regional vector surveillance and control programs. In this study, we model the environmental requirements of the principal North and Central American phlebotomine species and analyze three niche characteristics over future climate change scenarios: i) potential change in niche breadth, ii) direction and magnitude of niche centroid shifts, iii) shifts in elevation range. Niche identity between confirmed or incriminated Leishmania vector sand flies in Mexico, and human cases were analyzed. Niche models were constructed using sand fly occurrence datapoints from Canada, USA, Mexico, Guatemala and Belize. Nine non-correlated bioclimatic and four topographic data layers were used as niche components using GARP in OpenModeller. Both B2 and A2 climate change scenarios were used with two general circulation models for each scenario (CSIRO and HadCM3), for 2020, 2050 and 2080. There was an increase in niche breadth to 2080 in both scenarios for all species with the exception of Lutzomyia vexator. The principal direction of niche centroid displacement was to the northwest (64%), while the elevation range decreased greatest for tropical, and least for broad-range species. Lutzomyia cruciata is the only epidemiologically important species with high niche identity with that of Leishmania spp. in Mexico. Continued landscape modification in future climate change will provide an increased opportunity for the geographic expansion of NCA sand flys' ENM and human exposure to vectors of Leishmaniases.

  6. Current and future niche of North and Central American sand flies (Diptera: psychodidae in climate change scenarios.

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    David Moo-Llanes

    Full Text Available Ecological niche models are useful tools to infer potential spatial and temporal distributions in vector species and to measure epidemiological risk for infectious diseases such as the Leishmaniases. The ecological niche of 28 North and Central American sand fly species, including those with epidemiological relevance, can be used to analyze the vector's ecology and its association with transmission risk, and plan integrated regional vector surveillance and control programs. In this study, we model the environmental requirements of the principal North and Central American phlebotomine species and analyze three niche characteristics over future climate change scenarios: i potential change in niche breadth, ii direction and magnitude of niche centroid shifts, iii shifts in elevation range. Niche identity between confirmed or incriminated Leishmania vector sand flies in Mexico, and human cases were analyzed. Niche models were constructed using sand fly occurrence datapoints from Canada, USA, Mexico, Guatemala and Belize. Nine non-correlated bioclimatic and four topographic data layers were used as niche components using GARP in OpenModeller. Both B2 and A2 climate change scenarios were used with two general circulation models for each scenario (CSIRO and HadCM3, for 2020, 2050 and 2080. There was an increase in niche breadth to 2080 in both scenarios for all species with the exception of Lutzomyia vexator. The principal direction of niche centroid displacement was to the northwest (64%, while the elevation range decreased greatest for tropical, and least for broad-range species. Lutzomyia cruciata is the only epidemiologically important species with high niche identity with that of Leishmania spp. in Mexico. Continued landscape modification in future climate change will provide an increased opportunity for the geographic expansion of NCA sand flys' ENM and human exposure to vectors of Leishmaniases.

  7. Current and Future Niche of North and Central American Sand Flies (Diptera: Psychodidae) in Climate Change Scenarios

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    Moo-Llanes, David; Ibarra-Cerdeña, Carlos N.; Rebollar-Téllez, Eduardo A.; Ibáñez-Bernal, Sergio; González, Camila; Ramsey, Janine M.

    2013-01-01

    Ecological niche models are useful tools to infer potential spatial and temporal distributions in vector species and to measure epidemiological risk for infectious diseases such as the Leishmaniases. The ecological niche of 28 North and Central American sand fly species, including those with epidemiological relevance, can be used to analyze the vector's ecology and its association with transmission risk, and plan integrated regional vector surveillance and control programs. In this study, we model the environmental requirements of the principal North and Central American phlebotomine species and analyze three niche characteristics over future climate change scenarios: i) potential change in niche breadth, ii) direction and magnitude of niche centroid shifts, iii) shifts in elevation range. Niche identity between confirmed or incriminated Leishmania vector sand flies in Mexico, and human cases were analyzed. Niche models were constructed using sand fly occurrence datapoints from Canada, USA, Mexico, Guatemala and Belize. Nine non-correlated bioclimatic and four topographic data layers were used as niche components using GARP in OpenModeller. Both B2 and A2 climate change scenarios were used with two general circulation models for each scenario (CSIRO and HadCM3), for 2020, 2050 and 2080. There was an increase in niche breadth to 2080 in both scenarios for all species with the exception of Lutzomyia vexator. The principal direction of niche centroid displacement was to the northwest (64%), while the elevation range decreased greatest for tropical, and least for broad-range species. Lutzomyia cruciata is the only epidemiologically important species with high niche identity with that of Leishmania spp. in Mexico. Continued landscape modification in future climate change will provide an increased opportunity for the geographic expansion of NCA sand flys' ENM and human exposure to vectors of Leishmaniases. PMID:24069478

  8. Sand fly vectors (Diptera, Psychodidae) of American visceral leishmaniasis areas in the Atlantic Forest, State of Espírito Santo, southeastern Brazil.

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    Pinto, Israel de Souza; Ferreira, Adelson Luiz; Valim, Valéria; Carvalho, Felipe dos Santos; da Silva, Giovana Marques; Falcão, Alda Lima; Dietze, Reynaldo; Falqueto, Aloísio

    2012-06-01

    The aim of this study was to evaluate the sand fly fauna of American visceral leishmaniasis (AVL) endemic areas within the Central Atlantic Forest Biodiversity Corridor, State of Espírito Santo, southeastern Brazil. The sand fly captures were performed between January, 1989 and December, 2003 in localities where autochthonous cases of AVL were recorded, as well as in their boundary areas. Sand flies were collected from surrounding houses and domestic animal shelters using two to five CDC automatic light traps, and manual captures were also performed using mouth aspirators in one illuminated Shannon trap during the first four hours of the night. We used cladistic analysis to determine the geographic relationships among the collected sand fly species as well as the index species for the occurrence of other sand flies. A total of 62,469 sand flies belonging to 17 species and eight genera was collected in 164 localities from nine municipalities with AVL records. The richness (S=17) and diversity (H=0.971) of sand flies were lower than in conservation areas and similar to modified environments in the Atlantic Forest of Espírito Santo. Lutzomyia longipalpis was identified in 79 localities. The cladistic analysis identified Evandromyia lenti as the index species for Lutzomyia longipalpis. The latter seems to be the main vector of AVL in the Central Atlantic Forest Biodiversity Corridor due to its high abundance and distribution matching the disease occurrence. Therefore, Evandromyia lenti may be used as an index species for the occurrence of Lutzomyia longipalpis.

  9. Molecular detection of the blood meal source of sand flies (Diptera: Psychodidae) in a transmission area of American cutaneous leishmaniasis, Paraná State, Brazil.

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    Baum, Maurício; de Castro, Edilene Alcântara; Pinto, Mara Cristina; Goulart, Thais Marchi; Baura, Walter; Klisiowicz, Débora do Rocio; Vieira da Costa-Ribeiro, Magda Clara

    2015-03-01

    The feeding behavior of sand flies provides valuable information about the vector/host interactions and elucidates the epidemiological patterns of American cutaneous leishmaniasis (ACL) transmission. The aim of this study was to identify the blood meal sources of sand flies in endemic areas of leishmaniasis in Paraná State through polymerase chain reaction (PCR) amplification of a prepronociceptin (PNOC) gene fragment and its subsequent DNA sequencing. Moreover, molecular assays were conducted to evaluate the sensitivity and reproducibility of the PNOC gene amplification. Besides that, a time-course digestion test of the blood using sand flies that fed artificially on BALB/c mice was performed. Of 1263 female sand flies collected in the field, 93 (3.6%) specimens were engorged and 27 allowed efficient amplification of the PNOC gene. These flies had fed on equine (Equus caballus), porcine (Sus scrofa) and canine (Canis lupus familiaris) species. The results also showed that the identification of the blood meal sources of the sand flies using the molecular method was directly linked to the level of digestion of the blood (time-course) and not to the amount of blood that had been ingested or to the presence of inhibitors in the blood.

  10. A soil emergence trap for collections of phlebotomine sand flies

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    Casanova Cláudio

    2001-01-01

    Full Text Available The identification of breeding sites of sand flies is of great epidemiological interest. A soil emergence trap for investigating potential sand fly breeding sites is described. The trap was tested in two rural areas in the Mogi Guaçu River Valley where the American cutaneous leishmaniasis is an endemic disease. Seventy-three sand fly individuals of three species, Lutzomyia intermedia s. l., L. whitmani and L. pessoai, were collected on the forest floor and peridomicile.

  11. Natural Leishmania (Viannia) spp. infections in phlebotomine sand flies (Diptera: Psychodidae) from the Brazilian Amazon region reveal new putative transmission cycles of American cutaneous leishmaniasis.

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    de Souza, Adelson Alcimar Almeida; Dos Santos, Thiago Vasconcelos; Jennings, Yara Lúcia Lins; Ishikawa, Edna Aoba Yassui; Barata, Iorlando da Rocha; Silva, Maria das Graças Soares; Lima, José Aprígio Nunes; Shaw, Jeffrey; Lainson, Ralph; Silveira, Fernando Tobias

    2016-01-01

    In Amazonian Brazil the etiological agents of American cutaneous leishmaniasis (ACL) belong to at least seven Leishmania species but little is known about the putative phlebotomine sand fly vectors in different biomes. In 2002-2003 a survey of the phlebotomine fauna was undertaken in the "Floresta Nacional do Tapajós", Belterra municipality, in the lower Amazon region, western Pará State, Brazil, where we recently confirmed the presence of a putative hybrid parasite, L. (V.) guyanensis × L. (V.) shawi shawi. Sand flies were collected from Centers for Disease Control (CDC) light traps, Shannon traps and by aspiration on tree bases. Females were dissected and attempts to isolate any flagellate infections were made by inoculating homogenized midguts into Difco B(45) medium. Isolates were characterized by monoclonal antibodies and isoenzyme electrophoresis. A total of 9,704 sand flies, belonging to 68 species or subspecies, were collected. Infections were found in the following sand flies: L. (V.) naiffi with Psychodopygus hirsutus hirsutus (1) and Ps. davisi (2); and L. (V.) shawi shawi with Nyssomyia whitmani (3) and Lutzomyia gomezi (1). These results provide strong evidence of new putative transmission cycles for L. (V.) naiffi and L. (V.) s. shawi.

  12. Fauna of phlebotomine sand flies (Diptera, Psychodidae in areas with endemic American cutaneous leishmaniasis in the State of Mato Grosso do Sul, Brazil

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    Paulo Silva de Almeida

    2013-03-01

    Full Text Available Fauna of phlebotomine sand flies (Diptera, Psychodidae in areas with endemic American cutaneous leishmaniasis in the State of Mato Grosso do Sul, Brazil. The aim of this study was to investigate the ecological aspects of the main vectors of American cutaneous leishmaniasis (ACL in four monitoring stations situated in the municipalities of Naviraí, Nova Andradina, Novo Horizonte do Sul and Rio Verde de Mato Grosso. For each monitoring station, the captures of sand flies were undertaken each month from July 2008 to June 2010 using CDC and Shannon traps. The CDC traps were installed simultaneously for three consecutive nights in three collection sites: intradomicile, peridomicile and edge of the forest. A Shannon trap was installed from dusk to 10 pm, inside the forest, one night per month. A total of 7,651 sand flies belonging to nine genera and twenty-nine species were captured. Nyssomyia neivai (52.95%, Psathyromyia hermanlenti (10.91%, Psathyromyia runoides (9.16%, Nyssomyia whitmani (7.95%, Psathyromyia aragaoi (4. 89%, Nyssomyia antunesi (3.14% and Evandromyia bourrouli (2.20% were the most frequent species. Approximately 65% of the sand flies were collected in the forest environment. The municipalities presented significantly different indexes of species diversity. Naviraí presented the lowest species diversity index, however, it showed the highest abundance. Novo Horizonte do Sul had the highest species diversity index, but the lowest abundance (< 5%. It is noteworthy the occurrence of vector species of Leishmania in the areas studied, especially in Naviraí, where Ny. neivai presented high frequencies which may explain the increased number of ACL cases in this municipality.

  13. Phlebotominae sand flies (Diptera: Psychodidae: potential vectors of American cutaneous leishmaniasis agents in the area associated with the Santo Antônio Hydroelectric System in Western Amazonian Brazil

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    Allan Kardec Ribeiro Galardo

    2015-06-01

    Full Text Available INTRODUCTION: An entomological study was conducted as part of a vector-monitoring program in the area associated with the Santo Antônio hydroelectric system in State of Rondônia, Western Amazonian Brazil. METHODS: Fourteen sampling sites were surveyed to obtain data on the potential vectors of Leishmania spp. in the area. Sand flies were collected from 2011 to 2014 during the months of January/February (rainy season, May/June (dry season, and September/October (intermediary season using light traps arranged in three vertical strata (0.5, 1, and 20m. RESULTS : A total of 7,575 individuals belonging to 62 species/subspecies were collected. The five most frequently collected sand flies were Psychodopygus davisi (Root (36.67%, Trichophoromyia ubiquitalis (Mangabeira (8.51%, Nyssomyia umbratilis (Ward & Fraiha (6.14%, Bichromomyia flaviscutellata (Mangabeira (5.74%, and Psychodopygus complexus (Mangabeira (5.25%. These species have been implicated in the transmission of American cutaneous leishmaniasis agents in the Brazilian Amazon region and described as potential vectors of this disease in the study area. CONCLUSIONS: Additional surveillance is needed, especially in areas where these five species of sand fly are found.

  14. Acetylcholinesterase mutations and organophosphate resistance in sand flies and mosquitoes

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    The sand fly, Phlebotomus papatasi (Scopoli) is a major vector of Leishamnia major, the principle causative agent of human cutaneous leishmaniasis in the Middle East, southern Europe, northern Africa, and Southern Asia. Sand fly bites and leishmaniasis significantly impacted U.S. military operations...

  15. Distribution of phlebotomine sand flies (Diptera: Psychodidae) in a primary forest-crop interface, Salta, Argentina.

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    Quintana, M G; Salomón, O D; De Grosso, M S Lizarralde

    2010-11-01

    Disordered urbanization and deforestation are the main activities proposed as causal factors of re-emergence of American cutaneous leishmaniasis caused by Leishmania braziliensis. The purpose of this work was to investigate, in the hyperendemic area of Argentina, the distribution of Phlebotomine sand flies at the modified primary vegetation-crop interface, as one of the potential sites where the effects of changing landscape on sand fly populations may be manifested. Twenty samplings were made between June 2004 and August 2005. The traps to catch sand flies were set on two consecutive nights every month (except in 5 mo, where it became every 15 d). The relationship between sand fly abundance and meteorological and landscape variables was analyzed using non-metric multidimensional scaling and Kendall's correlation coefficients. Lutzomyia neivai (Pinto) was the most abundant species, followed by Lutzomyia migonei (França), Lutzomyia cortelezzii (Brèthes), Lutzomyia shannoni (Dyar), and Lutzomyia punctigeniculata (Floch and Abonnenc). Traps located close to modified areas collected the greatest numbers of sand flies, whereas traps located in the least modified area (adjacent to the primary vegetation) collected the fewest. There was a strong negative correlation between the abundance of sand flies and precipitation. This study shows that even small modifications in the landscape led to an increase in sand fly abundance, mainly Lu. neivai, a Leishmania braziliensis vector. This underscores the need for recommendations about the risk of American cutaneous leishmaniasis before any environmental intervention is done in an endemic area, as well as for the monitoring of sand fly population dynamics at the site of intervention, before, during, and after the process.

  16. Study of sand fly fauna in an endemic area of American cutaneous leishmaniasis and canine visceral leishmaniasis in the municipality of Espírito Santo do Pinhal, São Paulo, Brazil.

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    Colla-Jacques, Fernanda Elisa; Casanova, Cláudio; Prado, Angelo Pires do

    2010-03-01

    Canine American visceral leishmaniasis and American cutaneous leishmaniasis (ACL) cases have been recorded in Espírito Santo do Pinhal. The aim of this study was to gather knowledge of the sand fly community and its population ecology within the municipality. Captures were made weekly over a period of 15 months in the urban, periurban and rural areas of the municipality, using automatic light traps. A total of 5,562 sand flies were collected, comprising 17 species. The most abundant species were Nyssomyia whitmani and Pintomyia pessoai in the rural area, Lutzomyia longipalpis and Ny. whitmani in the periurban area and Lu. longipalpis in the urban area. The highest species richness and greatest index species diversity were found in the rural area. The similarity index showed that urban and periurban areas were most alike. Lu. longipalpis was found in great numbers during both dry and humid periods. The presence of dogs infected with Leishmania infantum chagasi in the urban area indicates a high risk for the establishment of the disease in the region. A high abundance of Ny. whitmani and Pi. pessoai in the rural and periurban areas indicates the possibility of new cases of ACL occurring in and spreading to the periurban area of Espírito Santo do Pinhal.

  17. Study of sand fly fauna in an endemic area of American cutaneous leishmaniasis and canine visceral leishmaniasis in the municipality of Espírito Santo do Pinhal, São Paulo, Brazil

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    Fernanda Elisa Colla-Jacques

    2010-03-01

    Full Text Available Canine American visceral leishmaniasis and American cutaneous leishmaniasis (ACL cases have been recorded in Espírito Santo do Pinhal. The aim of this study was to gather knowledge of the sand fly community and its population ecology within the municipality. Captures were made weekly over a period of 15 months in the urban, periurban and rural areas of the municipality, using automatic light traps. A total of 5,562 sand flies were collected, comprising 17 species. The most abundant species were Nyssomyia whitmani and Pintomyia pessoai in the rural area, Lutzomyia longipalpis and Ny. whitmani in the periurban area and Lu. longipalpis in the urban area. The highest species richness and greatest index species diversity were found in the rural area. The similarity index showed that urban and periurban areas were most alike. Lu. longipalpis was found in great numbers during both dry and humid periods. The presence of dogs infected with Leishmania infantum chagasi in the urban area indicates a high risk for the establishment of the disease in the region. A high abundance of Ny. whitmani and Pi. pessoai in the rural and periurban areas indicates the possibility of new cases of ACL occurring in and spreading to the periurban area of Espírito Santo do Pinhal.

  18. Sand flies (Diptera: Psychodidae) in the urban area of the municipality of Cianorte, Paraná State, Brazil.

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    Cerino, Daniela A; Teodoro, Ueslei; Silveira, Thaís G V

    2009-01-01

    The endemicity of American cutaneous leishmaniasis (ACL) in the Cianorte municipality, Paraná State the occurrence of human cases with the probable infection locus in the urban area, the presence of a permanently preserved modified native forest in the urban perimeter, and the lack of knowledge of the fauna of sand flies in the municipality provided the impetus for this study. The objective of this study was to assess the fauna, frequency and seasonality of the sand flies in the peridomicile, forest and urban area of this municipality. Sand flies were collected using Falcão light traps installed in the peridomicile and forest, from July 2005 to June 2006. A total of 755 sand flies were collected; Nyssomyia whitmani (Antunes & Coutinho) (84.0%), followed by Nyssomyia neivai (Pinto) (12.7%) were the predominant species. The number of sand flies collected in the peridomicile was significantly higher than in the forest (P = 0.0068). The small number of sand flies collected, especially in the forest, may be related to the modifications to the environment on the edge of the Parque Cinturão Verde, which surrounds the urban area of the municipality. Five species of sand flies were distinguished in the urban area of Cianorte, with greater frequencies found in the peridomicile, especially from November to April. Our data illustrate the necessity of maintaining the measures that contributed to reduce human contact with sand flies, thereby reducing the transmission risk of ACL.

  19. Control of Phlebotomine Sand Flies in Iran: A Review Article

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    Mohammad Reza Yaghoobi-Ershadi

    2016-10-01

    Full Text Available Leishmaniasis has long been known as a significant public health challenge in many parts of Iran. Phlebotomus pa­patasi and P. sergenti are the vectors of Zoonotic Cutaneous Leishmaniasis and Anthroponotic Cutaneous Leish­maniasis respectively, and 5 species of sand flies including P. kandelakii, P. neglectus, P. perfiliewi, P. keshishiani and P. alexandri are considered as probable vectors of Zoonotic visceral leishmaniasis. A literature search was per­formed of the relevant multiple databases from 1966 to 2013 to include studies on sand flies, vector control, leish­maniasis, Phlebotomus. Sand fly control in Iran began in 1966 by Iranian researchers, and long-term evaluation of its effects was completed in the study areas of the country. Herein, a review of vector control strategies in Iran to com­bat leishmaniasis including indoor residual spraying, application of chemicals in rodent burrows, impregnation of bed nets and curtains with insecticides, the use of insect repellents, impregnation of dog collars and the susceptibility of sand fly vectors to various insecticides has been summarized thus far. The investigation of the behavioral patterns of the adults of different sand fly species, introduction of biological insecticide agents, the use of insecticidal plants and other novel strategies for the control of sand fly populations have received much attention in the areas of studies, hence should be recommended and improved since they provide optimistic results.

  20. Phlebotomine sand flies (Diptera, Psychodidae) in an American tegumentary leishmaniasis transmission area in northern Espírito Santo State, Brazil Fauna de flebotomíneos (Diptera, Psychodidae) em área de transmissão de leishmaniose tegumentar americana no norte do Estado do Espírito Santo, Brasil

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    Thieres Marassati das Virgens; Claudiney Biral dos Santos; Israel de Souza Pinto; Kleber Silveira da Silva; Fernanda Cristina Leal; Aloísio Falqueto

    2008-01-01

    American tegumentary leishmaniasis is endemic to the Espírito Santo State, Brazil, where it is widely distributed. The composition of the phlebotomine sand fly fauna in an American tegumentary leishmaniasis focus was determined by monthly sampling, using Shannon light traps in an Atlantic Forest reserve and adjacent habitat that had been modified by human activity. Seasonal fluctuations in numbers of the most abundant species were also monitored from June 2004 to May 2006. Of the 6,176 specim...

  1. New records of phlebotomine sand flies (Diptera: Psychodidae from Ecuador

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    J. Bruce Alexander

    1992-03-01

    Full Text Available The plebotomine sand fly fauna of Ecuador was surveyed in two 3-month collecting trips made in 1988 and 1990. A total of 12 provinces were visited, including three (Bolivar, Loja and Morona Santiago from wich no previous records to phlebotomines existed. Forty-six species were collected, 13 of wich, together with 1 subspecies and 1 genus (Warileya represented new records for the country. This survey increases the known number of species in Ecuador to 60. The distribuition of Ecuadorian sand flies is discussed in the light of these new findings.

  2. Aluminium: a natural adjuvant in Leishmania transmission via sand flies?

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    Maingon, Rhayza; Khela, Amandeep; Sampson, Christopher; Ward, Richard; Walker, Karen; Exley, Christopher

    2008-11-01

    Genetically identical Leishmania chagasi/infantum parasites cause both atypical cutaneous leishmaniasis and visceral leishmaniasis. In this report we have tested the first part of a hypothesis that states that the form of this disease that is manifested depends upon the adjuvant-like activity of aluminium of dietary origin accumulated in the salivary gland of the sand fly vector. In sand flies fed aluminium-supplemented sucrose we have used histochemistry to qualitatively identify aluminium in their salivary glands and graphite furnace atomic absorption spectrometry to quantify the aluminium content of dissected salivary glands. Aluminium may be acting as a natural adjuvant in some forms of leishmaniasis.

  3. Bacteria of Phlebotominae Sand Flies Collected in Western Iran

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    Somayeh Rafatbakhsh-Iran

    2015-08-01

    Full Text Available Microorganisms particularly bacteria presenting in insects such as Phlebotominae may play an important role in the epidemiology of human infectious disease. Nowadays, because of vector implications, the routine methods of controlling and spraying have no more beneficial effects on vectors and reservoirs. Little knows about the prevalence and diversity of sand fly bacteria. The main objective of this study was to determine the presence of bacteria of phlebotominae sand flies collected in Hamadan, west of Iran. This information is important in order to development of vector control strategies. The microbial flora of Phlebotomus papatasi and P. sergenti the main vector of Cutaneous Leishmaniasis in the old world, were investigated. We characterized 8 bacteria, including 5 Gram-negative bacteria: Acinetobacter lwoffii, Pseudomonas aeruginosa, Enterobacter cloacae, Edvardsiela sp. and Proteus mirabilis and Gram-positive bacteria: Bacillus subtilis, Staphylococcus saprophyticus and Micrococcus luteus. Our study provides some data on the microbiota diversity of field-collected sand flies for the first time in Hamadan. Our results indicate that there is a range of variation of aerobic bacteria inhabiting sand fly, which possibly reflect the ecological condition of the habitat where the fly breeds. Microbiota is increasingly regarded as an important factor for modulating vector competence in insect vectors. So, mirobiota can be effects on the biology of phlebotominae and their roles in the sandfly-Leishmania interaction. Further experiments are required to clearly delineate the vectorial role of sand flies. Because it is probable that in the future, factors such as environmental changes, migration and urbanization can ease the transmission of leishmaniasis in this area.

  4. Sampling strategies for phlebotomine sand flies (Diptera: Psychodidae) in Europe.

    Science.gov (United States)

    Alten, B; Ozbel, Y; Ergunay, K; Kasap, O E; Cull, B; Antoniou, M; Velo, E; Prudhomme, J; Molina, R; Bañuls, A-L; Schaffner, F; Hendrickx, G; Van Bortel, W; Medlock, J M

    2015-12-01

    The distribution of phlebotomine sand flies is widely reported to be changing in Europe. This can be attributed to either the discovery of sand flies in areas where they were previously overlooked (generally following an outbreak of leishmaniasis or other sand fly-related disease) or to true expansion of their range as a result of climatic or environmental changes. Routine surveillance for phlebotomines in Europe is localized, and often one of the challenges for entomologists working in non-leishmaniasis endemic countries is the lack of knowledge on how to conduct, plan and execute sampling for phlebotomines, or how to adapt on-going sampling strategies for other haematophagous diptera. This review brings together published and unpublished expert knowledge on sampling strategies for European phlebotomines of public health concern in order to provide practical advice on: how to conduct surveys; the collection and interpretation of field data; suitable techniques for the preservation of specimens obtained by different sampling methods; molecular techniques used for species identification; and the pathogens associated with sand flies and their detection methods.

  5. Sand fly evolution and its relationship to Leishmania transmission

    Directory of Open Access Journals (Sweden)

    PD Ready

    2000-08-01

    Full Text Available The evolutionary relationships of sand flies and Leishmania are discussed in this report, which draws distinctions between co-association, co-evolution and co-speciation (or co-cladogenesis. Examples focus on Phlebotomus vectors of Le. infantum and Le. major in the Mediterranean subregion.

  6. Extraction of vanadium from athabasca tar sands fly ash

    Science.gov (United States)

    Gomez-Bueno, C. O.; Spink, D. R.; Rempel, G. L.

    1981-06-01

    The production of refinery grade oil from the Alberta tar sands deposits as currently practiced by Suncor (formally Great Canadian Oil Sands Ltd.—GCOS) generates a substantial amount of petroleum coke fly ash which contains appreciable amounts of valuable metals such as vanadium, nickel and titanium. Although the recovery of vanadium from petroleum ash is a well established commercial practice, it is shown in the present work that such processes are not suitable for recovery of vanadium from the GCOS fly ash. The fact that the GCOS fly ash behaves so differently when compared to other petroleum fly ash is attributed to its high silicon and aluminum contents which tie up the metal values in a silica-alumina matrix. Results of experiments carried out in this investigation indicate that such matrices can be broken down by application of a sodium chloride/water roast of the carbon-free fly ash. Based on results from a series of preliminary studies, a detailed investigation was undertaken in order to define optimum conditions for a vanadium extraction process. The process developed involves a high temperature (875 to 950 °C) roasting of the fly ash in the presence of sodium chloride and water vapor carried out in a rotary screw kiln, followed by dilute sodium hydroxide atmosphereic leaching (98 °C) to solublize about 85 pet of the vanadium originally present in the fly ash. It was found that the salt roasting operation, besides enhancing vanadium recovery, also inhibits silicon dissolution during the subsequent leaching step. The salt roasting treatment is found to improve vanadium recovery significantly when the fly ash is fully oxidized. This is easily achieved by burning off the carbon present in the “as received” fly ash under excess air. The basic leaching used in the new process selectively dissolves vanadium from the roasted ash, leaving nickel and titanium untouched.

  7. Molecular Diversity between Salivary Proteins from New World and Old World Sand Flies with Emphasis on Bichromomyia olmeca, the Sand Fly Vector of Leishmania mexicana in Mesoamerica

    Science.gov (United States)

    Townsend, Shannon; Pasos-Pinto, Silvia; Sanchez, Laura; Rasouli, Manoochehr; B. Guimaraes-Costa, Anderson; Aslan, Hamide; Francischetti, Ivo M. B.; Oliveira, Fabiano; Becker, Ingeborg; Kamhawi, Shaden; Ribeiro, Jose M. C.; Jochim, Ryan C.; Valenzuela, Jesus G.

    2016-01-01

    Background Sand fly saliva has been shown to have proteins with potent biological activities, salivary proteins that can be used as biomarkers of vector exposure, and salivary proteins that are candidate vaccines against different forms of leishmaniasis. Sand fly salivary gland transcriptomic approach has contributed significantly to the identification and characterization of many of these salivary proteins from important Leishmania vectors; however, sand fly vectors in some regions of the world are still neglected, as Bichromomyia olmeca (formerly known as Lutzomyia olmeca olmeca), a proven vector of Leishmania mexicana in Mexico and Central America. Despite the importance of this vector in transmitting Leishmania parasite in Mesoamerica there is no information on the repertoire of B. olmeca salivary proteins and their relationship to salivary proteins from other sand fly species. Methods and Findings A cDNA library of the salivary glands of wild-caught B. olmeca was constructed, sequenced, and analyzed. We identified transcripts encoding for novel salivary proteins from this sand fly species and performed a comparative analysis between B. olmeca salivary proteins and those from other sand fly species. With this new information we present an updated catalog of the salivary proteins specific to New World sand flies and salivary proteins common to all sand fly species. We also report in this work the anti-Factor Xa activity of Lofaxin, a salivary anticoagulant protein present in this sand fly species. Conclusions This study provides information on the first transcriptome of a sand fly from Mesoamerica and adds information to the limited repertoire of salivary transcriptomes from the Americas. This comparative analysis also shows a fast degree of evolution in salivary proteins from New World sand flies as compared with Old World sand flies. PMID:27409591

  8. Geographical distribution of cutaneous leishmaniasis and sand flies in Pakistan.

    Science.gov (United States)

    Shakila, Ashraf; Bilqees, Fatima Mujib; Salim, Azra; Moinuddin, Moinuddin

    2006-01-01

    Cutaneous leishmaniasis is found in all the four provinces of Pakistan; these are NWFP, Balochistan, Sindh and Punjab. In Balochistan the areas from where the patients came are Uthal, Quetta and Ormara. The highest number of patients came from Quetta and least from Ormara. The patients included in this study were from the Mangopir and Chakewara, areas of Karachi. The infection is endemic in this country and the recent epidemics in the Dadu District and Nawabshah indicate its importance in the locality. The sand fly vector is found in all four provinces of Pakistan that are listed here. It is quite obvious that presence of leishmaniasis indicates the presence of sand flies and cutaneous leishmaniasis is more common.

  9. Molecular identification of sand flies (Diptera: Psychodidae) in eastern North America by using PCR-RFLP.

    Science.gov (United States)

    Minter, Logan M; Yu, Tian; Florin, David A; Nukmal, Nismah; Brown, Grayson C; Zhou, Xuguo

    2013-07-01

    Sand flies (Diptera: Psychodidae) are small blood-feeding dipterans that are primary vectors of numerous human and livestock pathogens. Effective surveillance programs with accurate identification tools are critical in development and implementation of modern integrated pest management programs. Although morphological keys are available for North American species, identification can still be challenging owing to the nature of sample preparation and incompatibility with molecular or biochemical-based pathology assays. Further, the potential for introduction of Old World or other exotic species is not accounted for by current keys. Herein, we present the development and validation of a restriction fragment-length polymorphism-based molecular identification method. Specifically, cytochrome c oxidase subunit I, a mitochondrial DNA marker, was used to distinguish two species of adult sand flies indigenous to eastern North America with two exotic species not yet known to occur in the United States.

  10. Laboratory Validation of the Sand Fly Fever Virus Antigen Assay

    Science.gov (United States)

    2015-12-01

    sand flies (Lutzomyia longipalpis) or Cache Valley virus, a distantly related bunyavirus. Results from this laboratory evaluation suggest that this...longipalpis) or Cache Valley virus, a distantly related bunyavirus. Results from this laboratory evaluation suggest that this assay may be used as a rapid...REPORT DOCUMENTATION PAGE Form Approved OMB No. 0704-0188 Public reporting burden for this collection of information is estimated to average 1 hour

  11. Leishmania development in sand flies: parasite-vector interactions overview

    Directory of Open Access Journals (Sweden)

    Dostálová Anna

    2012-12-01

    Full Text Available Abstract Leishmaniases are vector-borne parasitic diseases with 0.9 – 1.4 million new human cases each year worldwide. In the vectorial part of the life-cycle, Leishmania development is confined to the digestive tract. During the first few days after blood feeding, natural barriers to Leishmania development include secreted proteolytic enzymes, the peritrophic matrix surrounding the ingested blood meal and sand fly immune reactions. As the blood digestion proceeds, parasites need to bind to the midgut epithelium to avoid being excreted with the blood remnant. This binding is strictly stage-dependent as it is a property of nectomonad and leptomonad forms only. While the attachment in specific vectors (P. papatasi, P. duboscqi and P. sergenti involves lipophosphoglycan (LPG, this Leishmania molecule is not required for parasite attachment in other sand fly species experimentally permissive for various Leishmania. During late-stage infections, large numbers of parasites accumulate in the anterior midgut and produce filamentous proteophosphoglycan creating a gel-like plug physically obstructing the gut. The parasites attached to the stomodeal valve cause damage to the chitin lining and epithelial cells of the valve, interfering with its function and facilitating reflux of parasites from the midgut. Transformation to metacyclic stages highly infective for the vertebrate host is the other prerequisite for effective transmission. Here, we review the current state of knowledge of molecular interactions occurring in all these distinct phases of parasite colonization of the sand fly gut, highlighting recent discoveries in the field.

  12. Do Permethrin-Treated Screens Repel Sand Flies from Entering Houses ?

    Directory of Open Access Journals (Sweden)

    Basimike, M.

    2000-01-01

    Full Text Available The effects of permethrin-treated screens on sand flies entering treated houses were evaluated in Marigat area of Baringo District, Kenya. Screens treated with 0.50 g/m2 a. i. of permethrin 20 % E.C. were fitted inside houses and retreated every 6 months from January 1992 to December 1993. In the treated village, 40.62 % sand flies were caught inside while 67.34 % sand flies were collected outside houses. In the control village, 32.66 % sand flies were collected inside while 59.38 % sand flies were caught outside houses. The number of sand flies collected outside houses in the treated village was higher than those collected inside houses in the same village (X2 = 30.97, df = 11, P = 0.001. Twelve species of sand flies were collected in the area, of which nine species of the Sergentomyia and three species of the Phlebotomus genera. Phlebotomus martini and P. duboscqi, vecfors of visceral and cutaneous leishmaniasis respectively were collected inside houses in both treated and control villages. Permethrin-treated screens fitted inside houses were effective against sand flies as they reduced the number of flies entering houses. However, the treated screens did not seem to have any effect on sand fly species composition. Permethrin-treated screens are an important tool for controlling sand flies in the communities.

  13. Ecological Aspects of Phlebotomine Sand Flies (Diptera, Psychodidae, Phlebotominae) in Areas of American Cutaneous Leishmaniasis, in the Municipality of Paraty, Rio de Janeiro, Brazil. I-Index of Abundance by Location and Type of Capture.

    Science.gov (United States)

    Vieira, V R; Azevedo, A C R; Alves, J R C; Guimarães, A E; Aguiar, G M

    2015-09-01

    The description of the first and autochthonous case of diffuse cutaneous leishmaniasis in the municipality of Paraty, State of Rio de Janeiro, brought the interest of this study. Sand flies were captured over a 3-yr period. Using manual suction tubes, sand flies were collected from the inner and outer walls of homes, in the living spaces of domestic animals, and in Shannon light traps, which were set up outside homes and in the forest. CDC light traps were installed inside homes, around the exterior of the houses, and along the divide and within the forest. A total of 102,937 sand flies were collected, representing 23 species--three from the genus Brumptomyia and 20 from the genus Lutzomyia. Of these, six species, Lutzomyia intermedia, Lutzomyia fischeri, Lutzomyia migonei, Lutzomyia whitmani, and Lutzomyia pessoai have already been recorded as being naturally infected by Leishmania braziliensis, and one species, Lutzomyia ayrozai, by Leishmania naiffi. Lu. intermedia is the vector of Le. braziliensis in the study area, particularly inside the homes and on the exterior of the houses. Lu. fischeri can also act as vector of Le. braziliensis in domestic environments and particularly in the wild. The third-ranked Lu. migonei was the most abundant in kennels, suggesting its canine affinity. Lu. whitmani, ranked fourth, still has characteristics indicative of the wild, but with a significant number located on the edge of the forest, suggesting a selection process of adaptation to the anthropic environment.

  14. Study on Type C Coal Fly ash as an Additive to Molding Sand for Steel Casting

    Science.gov (United States)

    Palaniappan, Jayanthi

    2017-04-01

    Study of physio-chemical properties studies such as granulometric analysis, moisture, X ray fluorescence etc. were performed with Type C coal—combustion fly ash to investigate their potential as a distinct option for molding sand in foundry, thereby reducing the dependency on latter. Technological properties study such as compressive strength, tensile strength, permeability and compaction of various compositions of fly ash molding sand (10, 20 and 30 % fly ash substitute to chemically bonded sand) were performed and compared with silica molding sand. Steel casting production using this fly ash molding sand was done and the casting surface finish and typical casting parameters were assessed. It was noted that a good quality steel casting could be produced using type C fly ash molding sand, which effectively replaced 20 % of traditional molding sand and binders thereby providing greater financial profits to the foundry and an effective way of fly ash utilization (waste management).

  15. Laboratory evaluation of the efficacy of fluorescent biomarkers for sugar-feeding sand flies (Diptera: Psychodidae).

    Science.gov (United States)

    Mascari, T M; Foil, L D

    2010-07-01

    The purpose of this study was to evaluate the use of four fluorescent dyes (rhodamine B, uranine O, auramine O, and erythrosin B) and two nonfluorescent dyes (carmoisine and indigotine) incorporated into sugar baits as biomarkers for phlebotomine sand flies. Each dye could be detected in sand flies fed baits with dye for 24 h when examined using bright field microscopy, although there was considerable variability in the marking produced; all sand flies that had ingested rhodamine B-treated sucrose solution were marked clearly. Sand flies that had ingested sucrose solution containing rhodamine B or uranine O at concentrations as low as 10 mg/L were consistently detected under fluorescence microscopy. None of the treatments in this study reduced the longevity of sand flies. All sand flies fed sucrose solution containing rhodamine B or uranine O were marked for at least 14 d, whereas only 20% of sand flies were marked 3 d after feeding on a carmoisine-treated solution. When rhodamine B and uranine O were combined in a single sucrose solution or when the dyes were fed sequentially to sand flies, both dyes could be detected in sand flies using fluorescence microscopy. We propose that rhodamine B- or uranine O-treated sucrose baits could be used in ecological studies or to identify portions of the adult sand fly population that could be targeted with insecticide-treated sugar baits.

  16. Efficacy of Permethrin Treated Bed Nets Against Leishmania major Infected Sand Flies.

    Science.gov (United States)

    Rowland, Tobin; Davidson, Silas A; Kobylinski, Kevin; Menses, Claudio; Rowton, Edgar

    2015-01-01

    Insecticide treated nets (ITNs) are a potential tool to help control sand flies and prevent Leishmaniasis. However, little is currently known about the response of Leishmania infected sand flies to ITNs. In this study, Phlebotomus duboscqi sand flies were infected with the parasite Leishmania major. Infected and noninfected sand flies were then evaluated against permethrin treated and untreated bed nets in a laboratory assay that required sand flies to pass through suspended netting material to feed on a mouse serving as an attractive host. The number of sand flies passing through the nets and blood feeding was recorded. There was not a significant difference in the ability of infected or noninfected sand flies to move through treated or untreated nets. Fewer sand flies entered the permethrin treated nets compared to the untreated nets, indicating that permethrin creates an effective barrier. The results show that in addition to reducing the nuisance bites of noninfected sand flies, ITNs also protect against Leishmania infected sand flies and therefore can play in key role in reducing the rates of Leishmaniasis. This study is important to the Department of Defense as it continues to develop and field new bed nets to protect service members.

  17. Study on phlebotomine sand fly (Diptera: Psychodidae) fauna in Belo Horizonte, state of Minas Gerais, Brazil.

    Science.gov (United States)

    Souza, Carina Margonari de; Pessanha, Jose Eduardo; Barata, Ricardo Andrade; Monteiro, Erika Michalsky; Costa, Daniela Carmargos; Dias, Edelberto Santos

    2004-12-01

    A study on the phlebotomine sand fly fauna in Belo Horizonte city, state of Minas Gerais, Brazil, was carried out. From April 2001 to March 2003, monthly systematic collections were performed in three houses from each of the nine regions of the city, using CDC light traps for four consecutive days. The traps were set into the houses and in peridomestic areas totaling 54 traps. A number of 3871 sand fly specimens of the genera Lutzomyia and Brumptomyia were collected. Sixty eight percent of the specimens were L. longipalpis and 16% L. whitmani, insect vectors of visceral and American cutaneous leishmaniasis, respectively. Environmental factors such as temperature, humidity, and frequency of precipitation suggest that the number of insects increases after rainy periods. During the same period mentioned above, seasonal captures were carried out in parks and green areas of Belo Horizonte, using Shannon trap. A total of 579 phlebotomine sand flies were collected from which 398 (68.7%) were females with the predominance of L. whitmani and L. monticola. Those specimens were used for natural infection examination, by polymerase chain reaction. No Leishmania DNA was present in any of the specimens tested.

  18. Study on phlebotomine sand fly (Diptera: Psychodidae fauna in Belo Horizonte, state of Minas Gerais, Brazil

    Directory of Open Access Journals (Sweden)

    Carina Margonari de Souza

    2004-12-01

    Full Text Available A study on the phlebotomine sand fly fauna in Belo Horizonte city, state of Minas Gerais, Brazil, was carried out. From April 2001 to March 2003, monthly systematic collections were performed in three houses from each of the nine regions of the city, using CDC light traps for four consecutive days. The traps were set into the houses and in peridomestic areas totaling 54 traps. A number of 3871 sand fly specimens of the genera Lutzomyia and Brumptomyia were collected. Sixty eight percent of the specimens were L. longipalpis and 16% L. whitmani, insect vectors of visceral and American cutaneous leishmaniasis, respectively. Environmental factors such as temperature, humidity, and frequency of precipitation suggest that the number of insects increases after rainy periods. During the same period mentioned above, seasonal captures were carried out in parks and green areas of Belo Horizonte, using Shannon trap. A total of 579 phlebotomine sand flies were collected from which 398 (68.7% were females with the predominance of L. whitmani and L. monticola. Those specimens were used for natural infection examination, by polymerase chain reaction. No Leishmania DNA was present in any of the specimens tested.

  19. American Las Vegas Sands Corp. Visiting Beijing

    Institute of Scientific and Technical Information of China (English)

    Li Yinghong; Liu Jinliang

    2006-01-01

    @@ On August 29, Wan Jifei, Chairman of CCPIT, meets the visiting delegation led by Sheldon G. Adelson,Chairman of the Board and principal owner of Las Vegas Sands Corp. in CCPIT. Zhao Zhenge, Vice Director of International Connection Department of CCPIT, Luo Guoxiong from Beijing China Exhibition Investment Company, Xu Jingyi, Assistant Director of American and Oceanian Affairs Division of CCPIT, also attended the meeting.

  20. Laboratory evaluation of rubidium as a long-lasting marker for bloodfeeding sand flies (Diptera: Psychodidae).

    Science.gov (United States)

    Mascari, T M; Stout, R W; Foil, L D

    2012-01-01

    The objective of this study was to evaluate the use of the trace element rubidium (Rb) as a long-lasting systemic biomarker for bloodfeeding females of the sand fly Phlebotomus papatasi Scopoli. Baits containing Rb chloride were found to be palatable to hamsters in this study. We were able to detect Rb using a portable X-ray fluorescence analyzer in all sand flies that fed on Rb-treated hamsters for at least 14 d postbloodmeal. We also detected Rb in sand flies that took a bloodmeal from hamsters up to 10 d after the hamsters were withdrawn from a Rb-treated diet. Results of this study constitute proof of concept for the incorporation of Rb chloride into rodent baits for marking bloodfeeding sand flies, and suggest that Rb marking could be used as a technique for evaluating rodent-targeted sand fly control methods and in ecological studies on sand flies.

  1. SPECIES DIVERSITY AND SEASONALITY OF PHLEBOTOMINE SAND FLIES (DIPTERA: PSYCHODIDAE) IN SATUN PROVINCE, THAILAND.

    Science.gov (United States)

    Panthawong, Amonrat; Chareonviriyaphap, Theeraphap; Phasuk, Jumnongjit

    2015-09-01

    Leishmaniasis is prevalent mainly in the southern provinces of Thailand where sand flies are considered to be an important vector. Sand flies were collected using Centers for Disease Control (CDC) light traps in Satun Province from June 2013 to July 2014. A total of 1,982 sand flies (1,228 females and 754 males) were collected. Only female sand flies were identified to the species level and were tested for Leishmania infection using polymerase chain reaction (PCR). Morphological identification revealed 2 genera and 9 species: Phlebotomus stantoni, P. argentipes, Sergentomyia gemmea, S. indica, S. barraudi, S. iyengari, S. bailyi, S. perturbans, and S. silvatica. S. gemmea (57.2%) was the most abundant species. The diversity of sand flies was highest in Thung Wa District. The sand flies were most abundant late in the hot season and early in the rainy season (April to June). The highest number of sand flies was collected in June. Significant correlations between the number of female sand flies and rainfall and between S. gemmea and rainfall were found. Of the female sand flies tested, none were positive for Leishmania spp.

  2. Feeding preferences of Lutzomyia longipalpis (Diptera: Psychodidae), the sand fly vector, for Leishmania infantum (Kinetoplastida: Trypanosomatidae).

    Science.gov (United States)

    Macedo-Silva, Virgínia P; Martins, Daniella R A; De Queiroz, Paula Vivianne Souza; Pinheiro, Marcos Paulo G; Freire, Caio C M; Queiroz, José W; Dupnik, Kathryn M; Pearson, Richard D; Wilson, Mary E; Jeronimo, Selma M B; Ximenes, Maria De Fátima F M

    2014-01-01

    Leishmania infantum, the causative agent of visceral leishmaniasis (VL) in Brazil, is spread mostly by the bite of the sand fly Lutzomyia longipalpis (Lutz & Neiva). We trapped sand flies in endemic neighborhoods near Natal, Brazil, where cases of human and dog VL were documented. Amplification of species-specific cytochrome b (Cyt b) genes by polymerase chain reaction revealed that sand flies from rural and periurban areas harbored blood from different sources. The most common source ofbloodmeal was human, but blood from dog, chicken, and armadillo was also present. We tested the preference for a source of bloodmeal experimentally by feeding L. longipalpis F1 with blood from different animals. There were significant differences between the proportion of flies engorged and number of eggs laid among flies fed on different sources, varying from 8.4 to 19 (P sand fly oviposition, but human blood also supported sand fly oviposition well. No sand flies fed on cats, and sand flies feeding on the opossum Monodelphis domestica Wagner produced no eggs. These data support the hypothesis that L. longipalpis is an eclectic feeder, and humans are an important source of blood for this sand fly species in periurban areas of Brazil.

  3. Breeding sites of Phlebotomus sergenti, the sand fly vector of cutaneous leishmaniasis in the Judean Desert.

    Directory of Open Access Journals (Sweden)

    Aviad Moncaz

    Full Text Available Phlebotomine sand flies transmit Leishmania, phlebo-viruses and Bartonella to humans. A prominent gap in our knowledge of sand fly biology remains the ecology of their immature stages. Sand flies, unlike mosquitoes do not breed in water and only small numbers of larvae have been recovered from diverse habitats that provide stable temperatures, high humidity and decaying organic matter. We describe studies designed to identify and characterize sand fly breeding habitats in a Judean Desert focus of cutaneous leishmaniasis. To detect breeding habitats we constructed emergence traps comprising sand fly-proof netting covering defined areas or cave openings. Large size horizontal sticky traps within the confined spaces were used to trap the sand flies. Newly eclosed male sand flies were identified based on their un-rotated genitalia. Cumulative results show that Phlebotomus sergenti the vector of Leishmania tropica rests and breeds inside caves that are also home to rock hyraxes (the reservoir hosts of L. tropica and several rodent species. Emerging sand flies were also trapped outside covered caves, probably arriving from other caves or from smaller, concealed cracks in the rocky ledges close by. Man-made support walls constructed with large boulders were also identified as breeding habitats for Ph. sergenti albeit less important than caves. Soil samples obtained from caves and burrows were rich in organic matter and salt content. In this study we developed and put into practice a generalized experimental scheme for identifying sand fly breeding habitats and for assessing the quantities of flies that emerge from them. An improved understanding of sand fly larval ecology should facilitate the implementation of effective control strategies of sand fly vectors of Leishmania.

  4. Midgut morphological changes and autophagy during metamorphosis in sand flies.

    Science.gov (United States)

    Malta, Juliana; Heerman, Matthew; Weng, Ju Lin; Fernandes, Kenner M; Martins, Gustavo Ferreira; Ramalho-Ortigão, Marcelo

    2017-03-11

    During metamorphosis, holometabolous insects undergo significant remodeling of their midgut and become able to cope with changes in dietary requirements between larval and adult stages. At this stage, insects must be able to manage and recycle available food resources in order to develop fully into adults, especially when no nutrients are acquired from the environment. Autophagy has been previously suggested to play a crucial role during metamorphosis of the mosquito. Here, we investigate the overall morphological changes of the midgut of the sand fly during metamorphosis and assess the expression profiles of the autophagy-related genes ATG1, ATG6, and ATG8, which are associated with various steps of the autophagic process. Morphological changes in the midgut start during the fourth larval instar, with epithelial degeneration followed by remodeling via the differentiation of regenerative cells in pre-pupal and pupal stages. The changes in the midgut epithelium are paired with the up-regulation of ATG1, ATG6 and ATG8 during the larva-adult transition. Vein, a putative epidermal growth factor involved in regulating epithelial midgut regeneration, is also up-regulated. Autophagy has further been confirmed in sand flies via the presence of autophagosomes residing within the cytoplasmic compartment of the pupal stages. An understanding of the underlying mechanisms of this process should aid the future management of this neglected tropical vector.

  5. Species composition and relative abundance of sand flies of the genus Lutzomyia (Diptera: Psychodidae) at an endemic focus of visceral leishmaniasis in Colombia.

    Science.gov (United States)

    Ferro, C; Morrison, A C; Torres, M; Pardo, R; Wilson, M L; Tesh, R B

    1995-07-01

    Ecological studies on the sand fly Lutzomyia longipalpis (Lutz & Neiva) were conducted during 1990-1993 at a small rural community in Colombia where American visceral leishmaniasis is endemic. Weekly sand fly collections were made from pigpens, houses, and natural resting sites, using hand-held aspirators, sticky (oiled) paper traps, and opossum-baited Disney traps. In total, 263,094 sand flies were collected; L. longipalpis predominated (86.1%), followed by L. trinidadensis (11.0%), L. cayennensis (2.7%), and 8 other Lutzomyia species. The species composition and sex ratio of these sand flies varied among sites and by collection method. L. longipalpis were captured most efficiently by direct aspiration from animal bait. Conversely, sticky paper traps, especially inside houses and at rock resting sites, collected a greater diversity of species, but a lower relative abundance of L. longipalpis.

  6. Relative potency of various insecticides for use in ATSBs against mosquitoes and sand flies

    Science.gov (United States)

    Mosquitoes and sand flies are important throughout the world as nuisance pests and vectors of a variety of human and livestock diseases. Control efforts are limited often to adulticide sprays and larvicides, however, environmental concerns restrict their use. Both mosquitoes and sand flies need to...

  7. Evaluation of ULV applications against Old World sand fly (Diptera: Psychodidae) species in equatorial Kenya

    Science.gov (United States)

    Reducing populations of phlebotomine sand flies in areas prevalent for human leishmaniases is of ongoing importance to US military operations and civilian populations in endemic regions. Collateral reduction of sand flies or human cases of leishmaniases during pesticide campaigns against vectors of ...

  8. The search for sand fly adults in a village in southern Egypt

    Science.gov (United States)

    There are several good papers in the literature describing methods for collecting adult phlebotomine sand flies from habitats putatively used for resting sites. The published data from such searches demonstrate that finding adult sand flies can be quite difficult even when using established methods....

  9. DNA barcoding for the identification of sand fly species (Diptera, Psychodidae, Phlebotominae) in Colombia.

    Science.gov (United States)

    Contreras Gutiérrez, María Angélica; Vivero, Rafael J; Vélez, Iván D; Porter, Charles H; Uribe, Sandra

    2014-01-01

    Sand flies include a group of insects that are of medical importance and that vary in geographic distribution, ecology, and pathogen transmission. Approximately 163 species of sand flies have been reported in Colombia. Surveillance of the presence of sand fly species and the actualization of species distribution are important for predicting risks for and monitoring the expansion of diseases which sand flies can transmit. Currently, the identification of phlebotomine sand flies is based on morphological characters. However, morphological identification requires considerable skills and taxonomic expertise. In addition, significant morphological similarity between some species, especially among females, may cause difficulties during the identification process. DNA-based approaches have become increasingly useful and promising tools for estimating sand fly diversity and for ensuring the rapid and accurate identification of species. A partial sequence of the mitochondrial cytochrome oxidase gene subunit I (COI) is currently being used to differentiate species in different animal taxa, including insects, and it is referred as a barcoding sequence. The present study explored the utility of the DNA barcode approach for the identification of phlebotomine sand flies in Colombia. We sequenced 700 bp of the COI gene from 36 species collected from different geographic localities. The COI barcode sequence divergence within a single species was sand flies from Colombia.

  10. Evaluation of ULV applications against Old World sand fly species in equatorial Kenya

    Science.gov (United States)

    Reducing populations of phlebotomine sand flies in areas prevalent for leishmaniases is of ongoing importance to U.S. military operations. Collateral reduction of sand flies or human cases of leishmaniases during pesticide campaigns against vectors of malaria indicate that residuals like DDT can be ...

  11. The immune response to sand fly salivary proteins and its influence on Leishmania immunity

    Directory of Open Access Journals (Sweden)

    Regis eGomes

    2012-05-01

    Full Text Available Leishmaniasis is a vector-borne disease transmitted by bites of phlebotomine sand flies. During Leishmania transmission, sand fly saliva is co-inoculated with parasites into the skin of the mammalian host. Sand fly saliva consists of roughly thirty different salivary proteins, many with known roles linked to blood feeding facilitation. Apart from the anti-hemostatic capacity of saliva, several sand fly salivary proteins have been shown to be immunogenic upon multiple contacts with a mammalian host. Immunization with single immunogenic salivary proteins or exposure to uninfected bites can produce protective immune responses against leishmaniasis. These sand fly salivary proteins induce cellular immune responses and/or antibodies. Antibodies to saliva are not required for protection in a mouse model against leishmaniasis. A strong body of evidence points to the role for saliva-specific T cells producing IFN-γ in the form of a delayed-type hypersensitivity reaction at the bite site as the main protective response. Herein, we review immunity to sand fly salivary proteins in the context of its vector-parasite-host combinations and vaccine potential, as well as some recent advances to shed light on the mechanism of how an immune response to sand fly saliva protects against leishmaniasis.

  12. Laboratory evaluation of insecticide-treated sugar baits for control of phlebotomine sand flies (Diptera: Psychodidae).

    Science.gov (United States)

    Mascari, T M; Foil, L D

    2010-12-01

    The purpose of this study was to evaluate the use of boric acid, imidacloprid, ivermectin, or abamectin incorporated into sugar baits as oral toxicants for adult phlebotomine sand flies. Variable toxicity of insecticide-sugar bait solutions to adult male and female sand flies was demonstrated, based on male female median lethal concentration values of 0.10-0.08, 6.13-9.53, and 9.03-18.11 mg/liter of imidacloprid, ivermectin, and abamectin, respectively. Complete control of sand flies could not be achieved with as high as 40 g/liter of boric acid in sugar bait solution; concentrations >40 g/liter were found repellent to the sand flies. Uranine O (a fluorescent tracer dye that can be used to measure the ingestion of sugar baits by sand flies) did not interact negatively with imidacloprid, ivermectin, or abamectin when it was combined with the insecticides in a sugar bait. Also, incorporation of imidacloprid, ivermectin, or abamectin into sugar baits did not reduce the effect whether adult male and female sand flies fed on these sugar baits. We propose that imidacloprid, ivermectin, or abamectin could be used to control adult sand fly populations with targeted use of insecticide-treated sugar baits.

  13. Fly-ash-amended sand as filter media in bioretention cells to improve phosphorus removal.

    Science.gov (United States)

    Zhang, Wei; Brown, Glenn O; Storm, Daniel E; Zhang, Hailin

    2008-06-01

    This study identified material with high phosphorus sorption suitable for bioretention filter media. Materials examined were fly ash, two expanded shales, peat moss, limestone, and two common Oklahoma soils--Teller loam and Dougherty sand. The peat moss was a phosphorus source, while the two soils, limestone, and one expanded shale had only modest sorption capacity. One expanded shale and the fly ash had significant phosphorus sorption. Fly ash is unsuitable for use in a pure form, as a result of its low permeability, but phosphorus sorption on the sand was increased significantly with the incorporation of small amounts of fly ash. Column leaching experiments found that the sand with 2.5 and 5% fly ash and the better expanded shale had linear, non-equilibrium transport retardation factors of 272, 1618, and 185, with first-order rate coefficients of 0.153, 0.0752, and 0.113 hour(-1), respectively. Desorption experiments showed that the phosphorus sorption on the sand/fly ash mixture is largely nonreversible. Transport simulation assuming a 1-m-deep sand/fly ash treatment layer, with 5% of the watershed area, showed that the sand/fly ash filter media could effectively treat 1 mg/L influent for 12 years in a paved watershed and 34 years in a grassed watershed before exceeding Oklahoma's scenic rivers' phosphorus criterion of 0.037 mg/L. Significant phosphorus removal would continue for over 100 years.

  14. Investigation of the bacterial communities associated with females of Lutzomyia sand fly species from South America.

    Directory of Open Access Journals (Sweden)

    Mauricio R V Sant'Anna

    Full Text Available Phlebotomine sand flies are vectors of Leishmania that are acquired by the female sand fly during blood feeding on an infected mammal. Leishmania parasites develop exclusively in the gut lumen during their residence in the insect before transmission to a suitable host during the next blood feed. Female phlebotomine sand flies are blood feeding insects but their life style of visiting plants as well as animals, and the propensity for larvae to feed on detritus including animal faeces means that the insect host and parasite are exposed to a range of microorganisms. Thus, the sand fly microbiota may interact with the developing Leishmania population in the gut. The aim of the study was to investigate and identify the bacterial diversity associated with wild adult female Lutzomyia sand flies from different geographical locations in the New World. The bacterial phylotypes recovered from 16S rRNA gene clone libraries obtained from wild caught adult female Lutzomyia sand flies were estimated from direct band sequencing after denaturing gradient gel electrophoresis of bacterial 16 rRNA gene fragments. These results confirm that the Lutzomyia sand flies contain a limited array of bacterial phylotypes across several divisions. Several potential plant-related bacterial sequences were detected including Erwinia sp. and putative Ralstonia sp. from two sand fly species sampled from 3 geographically separated regions in Brazil. Identification of putative human pathogens also demonstrated the potential for sand flies to act as vectors of bacterial pathogens of medical importance in addition to their role in Leishmania transmission.

  15. Comparative efficacy of three suction traps for collecting phlebotomine sand flies (Diptera: Psychodidae) in open habitats.

    Science.gov (United States)

    Faiman, Roy; Cuño, Ruben; Warburg, Alon

    2009-06-01

    The efficacy of three suction traps for trapping phlebotomine sand flies (Diptera: Psychodidae) was compared. Traps were baited with Co(2) and used without any light source. CO(2)-baited CDC traps were evaluated either in their standard downdraft orientation or inverted (iCDC traps). Mosquito Magnet-X (MMX) counterflow geometry traps were tested in the updraft orientation only. Both updraft traps (iCDC and MMX) were deployed with their opening ∼10 cm from the ground while the opening of the downdraft (CDC) trap was ∼40 cm above ground. Comparisons were conducted in two arid locations where different sand fly species prevail. In the Jordan Valley, 3,367 sand flies were caught, 2,370 of which were females. The predominant species was Phlebotomus (Phlebotomus) papatasi, Scopoli 1786 (>99%). The updraft-type traps iCDC and MMX caught an average of 118 and 67.1 sand flies per trap night, respectively. The CDC trap caught 32.9 sand flies on average per night, significantly less than the iCDC traps. In the Judean desert, traps were arranged in a 3 × 3 Latin square design. A total of 565 sand flies were caught, 345 of which were females. The predominant species was P. (Paraphlebotomus) sergenti Parrot 1917 (87%). The updraft traps iCDC and MMX caught an average of 25.6 and 17.9 sand flies per trap per night, respectively. The CDC trap caught 7.8 sand flies on average per night, significantly less than the iCDC traps. The female to male ratio was 1.7 on average for all trap types. In conclusion, updraft traps deployed with their opening close to the ground are clearly more effective for trapping sand flies than downdraft CDC traps in open habitats.

  16. Radiation of the Oriental phlebotomine sand flies (Diptera: Psychodidae)

    Institute of Scientific and Technical Information of China (English)

    Kandan llango

    2011-01-01

    The historical biogeography ofphlebotomine sand fly taxa Hertigia, Warileya,Phlebotomus (Idiophlebotomus), P. (Spelaeophlebotonus), P (Anaphlebotomus), and P.(Euphlebotomus) and the Phlebotomus (Euphlebotomus) argentipes species complex was investigated using phylogenetic inference from comparative genital morphology, distribution of ancestral taxa, fossil evidence and geological age. Idiophlebotomus and Euphlebotomus occur in the Oriental region with one species from northeast Australia, whereas Anaphlebotomus occurs both in the Afro-tropical and Oriental regions. These disjunct distribution patterns across the Oriental region and the present day distribution are likely to be vicariance due to break of Gondwanaland. Fossil records, extant taxa distribution,phylogenetic analysis of the Old World Phlebotominae and paleogeography suggest that ancestors ofIdiophlebotomus and Euphlebotomus originated apparently in the Cimmerian continent of northern margin of Gondwanaland in the early Permian (290 million years ago, MYA) and subsequently radiated in the Mesozoic by tectonic vicariance. The Phlebotomus argentipes species complex occurs in the South and South-east Asian countries and transmits the protozoan parasite Leishmania donovani that causes visceral leishmaniasis (Kala-azar) in India, Bangladesh and Nepal. The phylogeography ofP. argentipes was caused through vicariance followed by dispersal events from 5O MYA (the Eocene) until the Recent era.

  17. [Rearing immature horse flies (Diptera: Tabanidae) by using a substrate of bryophytes and sand].

    Science.gov (United States)

    Ferreira, Ruth L M; Rafael, José A

    2006-01-01

    A new method for rearing immature horse flies by using a substrate of bryophytes and sand is described and the advantages of such substrate for maintenance of species with long development periods are discussed.

  18. Phylogenetics of the Phlebotomine Sand Fly Group Verrucarum (Diptera: Psychodidae: Lutzomyia)

    Science.gov (United States)

    Cohnstaedt, Lee W.; Beati, Lorenza; Caceres, Abraham G.; Ferro, Cristina; Munstermann, Leonard E.

    2011-01-01

    Within the sand fly genus Lutzomyia, the Verrucarum species group contains several of the principal vectors of American cutaneous leishmaniasis and human bartonellosis in the Andean region of South America. The group encompasses 40 species for which the taxonomic status, phylogenetic relationships, and role of each species in disease transmission remain unresolved. Mitochondrial cytochrome c oxidase I (COI) phylogenetic analysis of a 667-bp fragment supported the morphological classification of the Verrucarum group into series. Genetic sequences from seven species were grouped in well-supported monophyletic lineages. Four species, however, clustered in two paraphyletic lineages that indicate conspecificity—the Lutzomyia longiflocosa–Lutzomyia sauroida pair and the Lutzomyia quasitownsendi–Lutzomyia torvida pair. COI sequences were also evaluated as a taxonomic tool based on interspecific genetic variability within the Verrucarum group and the intraspecific variability of one of its members, Lutzomyia verrucarum, across its known distribution. PMID:21633028

  19. Seasonal distribution of phlebotomine sand flies (Diptera: Psychodidae) in Tham Phra Phothisat temple, Saraburi province, Thailand.

    Science.gov (United States)

    Polseela, R; Apiwathnasorn, C; Samung, Y

    2011-08-01

    Phlebotomine sand flies have long been incriminated as vectors of leishmaniasis in various parts of both the Old and New World. Prompted by recent indigenous cases of leishmaniasis in Thailand, a bionomic study of sand flies was undertaken in Tham Phra Phothisat temple, Saraburi province. In this study, sand flies were collected using Centers for Disease Control (CDC) light traps, to clarify the activity patterns and species composition of the sand flies. Traps were laid from August 2005 to July 2006. The insects were collected monthly between 1800-0600 hours. A total of 8,131 sand flies were collected with a female:male ratio of 1.9:1. Sixteen species were identified, of which 5 belonged to the genus Phlebotomus, 9 to Sergentomyia and 1 to Chinius. Species comprised the abundant species (Sergentomyia silvatica 35.6%, Sergentomyia barraudi 18.1%, Sergentomyia anodontis, 17.1%, Sergentomyia iyengari 11.9%, and Sergentomyia gemmea 11.2%); the less common species (sand fly prevalence, with the highest peak in July. Soil samples collected were characterized by alkaline (pH 7.6).

  20. Caspar-like gene depletion reduces Leishmania infection in sand fly host Lutzomyia longipalpis.

    Science.gov (United States)

    Telleria, Erich L; Sant'Anna, Maurício R V; Ortigão-Farias, João R; Pitaluga, André N; Dillon, Viv M; Bates, Paul A; Traub-Csekö, Yara M; Dillon, Rod J

    2012-04-13

    Female phlebotomine sand flies Lutzomyia longipalpis naturally harbor populations of the medically important Leishmania infantum (syn. Leishmania chagasi) parasite in the gut, but the extent to which the parasite interacts with the immune system of the insect vector is unknown. To investigate the sand fly immune response and its interaction with the Leishmania parasite, we identified a homologue for caspar, a negative regulator of immune deficiency signaling pathway. We found that feeding antibiotics to adult female L. longipalpis resulted in an up-regulation of caspar expression relative to controls. caspar was differentially expressed when females were fed on gram-negative and gram-positive bacterial species. caspar expression was significantly down-regulated in females between 3 and 6 days after a blood feed containing Leishmania mexicana amastigotes. RNA interference was used to deplete caspar expression in female L. longipalpis, which were subsequently fed with Leishmania in a blood meal. Sand fly gut populations of both L. mexicana and L. infantum were significantly reduced in caspar-depleted females. The prevalence of L. infantum infection in the females fell from 85 to 45%. Our results provide the first insight into the operation of immune homeostasis in phlebotomine sand flies during the growth of bacterial and Leishmania populations in the digestive tract. We have demonstrated that the activation of the sand fly immune system, via depletion of a single gene, can lead to the abortion of Leishmania development and the disruption of transmission by the phlebotomine sand fly.

  1. Caspar-like Gene Depletion Reduces Leishmania Infection in Sand Fly Host Lutzomyia longipalpis*

    Science.gov (United States)

    Telleria, Erich L.; Sant'Anna, Maurício R. V.; Ortigão-Farias, João R.; Pitaluga, André N.; Dillon, Viv M.; Bates, Paul A.; Traub-Csekö, Yara M.; Dillon, Rod J.

    2012-01-01

    Female phlebotomine sand flies Lutzomyia longipalpis naturally harbor populations of the medically important Leishmania infantum (syn. Leishmania chagasi) parasite in the gut, but the extent to which the parasite interacts with the immune system of the insect vector is unknown. To investigate the sand fly immune response and its interaction with the Leishmania parasite, we identified a homologue for caspar, a negative regulator of immune deficiency signaling pathway. We found that feeding antibiotics to adult female L. longipalpis resulted in an up-regulation of caspar expression relative to controls. caspar was differentially expressed when females were fed on Gram-negative and Gram-positive bacterial species. caspar expression was significantly down-regulated in females between 3 and 6 days after a blood feed containing Leishmania mexicana amastigotes. RNA interference was used to deplete caspar expression in female L. longipalpis, which were subsequently fed with Leishmania in a blood meal. Sand fly gut populations of both L. mexicana and L. infantum were significantly reduced in caspar-depleted females. The prevalence of L. infantum infection in the females fell from 85 to 45%. Our results provide the first insight into the operation of immune homeostasis in phlebotomine sand flies during the growth of bacterial and Leishmania populations in the digestive tract. We have demonstrated that the activation of the sand fly immune system, via depletion of a single gene, can lead to the abortion of Leishmania development and the disruption of transmission by the phlebotomine sand fly. PMID:22375009

  2. Spatial Distribution of Phlebotomine Sand Fly Species (Diptera: Psychodidae) in Qom Province, Central Iran.

    Science.gov (United States)

    Saghafipour, Abedin; Vatandoost, Hassan; Zahraei-Ramazani, Ali Reza; Yaghoobi-Ershadi, Mohammad Reza; Rassi, Yavar; Shirzadi, Mohammad Reza; Akhavan, Amir Ahmad

    2017-01-01

    Zoonotic cutaneous leishmaniasis (ZCL) is transmitted to humans by phlebotomine sand fly bites. ZCL is a major health problem in Iran, where basic knowledge gaps about sand fly species diversity persist in some ZCL-endemic areas. This paper describes the richness and spatial distribution of sand fly species, collected with sticky traps, in Qom province, a ZCL-endemic area in central Iran, where sand fly fauna has been poorly studied. Collected species were mapped on urban and rural digital maps based on a scale of 1/50,000. All analyses were undertaken with rural- and urban-level precision, i.e., rural and urban levels were our basic units of analysis. After identifying the sand flies, high-risk foci were determined. For spatial analysis of vector species population, the entomological sampling sites were geo-referenced using GPS. Arc GIS 9.3 software was used to determine the foci with leishmaniasis vector species. Following the analyses, two genera (Phlebotomus and Sergentomyia) and 14 species were identified. Based on the mapping and sand fly dispersion analysis, the rural districts were categorized into three groups-infection reported, without infection, and no report. Based on Geographical Information System analyses, Kahak and Markazi districts were identified as high-risk foci with leishmaniasis vector species. These findings can act as a help guide to direct active control measures to the identified high-risk foci and, eventually, lead to reduction in incidence of the disease.

  3. DISTRIBUTION OF PHLEBOTOMINE SAND FLIES (DIPTERA:PSYCHODIDAE) IN LIMESTONE CAVES, KHAO PATHAWI, UTHAI THANI PROVINCE, THAILAND.

    Science.gov (United States)

    Polseela, R; Vitta, A; Apiwathnasorn, C

    2015-05-01

    This study investigated the species composition and density of the sand flies found inside four limestone caves at Khao Pathawi, Thap Than District, Uthai Thani Province. Sand flies were collected using Centers for Disease Control (CDC) light traps from October 2012 to September 2013. The sand flies were captured between 06:00 PM - 06:00 AM. A total of 11,817 sand flies were collected with a male:female ratio of 1.0:1.2 (5,325:6,492). The specimens were identified as eight species belonging to three genera Phlebotomus, Sergentomyia, Chinius, and comprised of S. anodontis, P. argentipes, P. stantoni, S. barraudi, S. silvatica, S. gemmea, S. indica, and C. barbazani. Sergentomyia anodontis (55.0%) was the predominant species followed by P. argentipes (33.6%) and others. Five species of sand fly were found throughout the year in this area: P. argentipes, P. stantoni, S. anodontis, S. barraudi and S. gemmea. The highest average density of sand flies was found in Ratree cave (35.0 sand flies per trap per night) and lowest in Bandai cave (29.0 sand flies per trap per night). The population of sand fly fluctuated from the highest peak in December (28.5%) to the lowest peak in May (2.3%). The distribution of sand fly species in attraction areas is important for the control program of infection risk of leishmaniasis.

  4. Effects of fly ash on the properties of Silicafume concrete by using Robo sand

    Energy Technology Data Exchange (ETDEWEB)

    Rao, Y.B.; Rafeeq, M. [Andhra Pradesh Engineering Research Lab., Hyderabad (India)

    2003-07-01

    The paper describes experiments to study the effects of fly ash from coal-fired power plants on the compressive and flexural strength, durability and permeability of typical high strength Silicafume concrete by using Robo sand (a synthetic sand). Tests results found there were improvements to some of the properties of the concrete when fly ash partly replaced Portland cement to an amount equal to 30% by mass of the cementitious materials. Fly ash enhances the workability of the Silicafume concrete but has a detrimental effect on its permeability. Further experiments are needed to obtain factual data for assessing design and economical consideration. 15 refs., 4 tabs.

  5. Assessing Insecticide Susceptibility of Laboratory Lutzomyia longipalpis and Phlebotomus papatasi Sand Flies (Diptera: Psychodidae: Phlebotominae).

    Science.gov (United States)

    Denlinger, David S; Lozano-Fuentes, Saul; Lawyer, Phillip G; Black, William C; Bernhardt, Scott A

    2015-09-01

    Chemical insecticides are effective for controlling Lutzomyia and Phlebotomus sand fly (Diptera: Psychodidae) vectors of Leishmania parasites. However, repeated use of certain insecticides has led to tolerance and resistance. The objective of this study was to determine lethal concentrations (LCs) and lethal exposure times (LTs) to assess levels of susceptibility of laboratory Lutzomyia longipalpis (Lutz and Nieva) and Phlebotomus papatasi (Scopoli) to 10 insecticides using a modified version of the World Health Organization (WHO) exposure kit assay and Centers for Disease Control and Prevention (CDC) bottle bioassay. Sand flies were exposed to insecticides coated on the interior of 0.5-gallon and 1,000-ml glass bottles. Following exposure, the flies were allowed to recover for 24 h, after which mortality was recorded. From dose-response survival curves for L. longipalpis and P. papatasi generated with the QCal software, LCs causing 50, 90, and 95% mortality were determined for each insecticide. The LCs and LTs from this study will be useful as baseline reference points for future studies using the CDC bottle bioassays to assess insecticide susceptibility of sand fly populations in the field. There is a need for a larger repository of sand fly insecticide susceptibility data from the CDC bottle bioassays, including a range of LCs and LTs for more sand fly species with more insecticides. Such a repository would be a valuable tool for vector management.

  6. Study of phlebotomine sand flies (Diptera: Psychodidae) collected in a Leishmania-endemic area of the metropolitan region of Belo Horizonte, Brazil.

    Science.gov (United States)

    Carvalho, Gustavo M L; Gontijo, Célia M F; Falcão, Alda L; Andrade Filho, José D

    2010-11-01

    Phlebotomine sand flies are distributed across nearly all faunal regions of the world, represented by over 800 species, of which many are important vectors of human pathogens. Brazil is currently faced with the expansion and urbanization of leishmaniases, with an increase in the numbers of human cases and seropositive dogs in various medium-sized to large cities. The objective of the current study was to survey the phlebotomine sand fly species in an area endemic for American cutaneous leishmaniasis (ACL) and American visceral leishmaniasis (AVL), i.e., the municipal district of Santa Luzia, lying within the metropolitan region of Belo Horizonte in the Brazilian State of Minas Gerais. Sand flies were collected monthly in 2004-2005 using modified Falcão light traps hung in the peridomiciles of houses and surrounding wooded areas in the district of Baronesa. A total of 1,552 sand flies belonging to seven species was collected, and an interesting pattern of the distribution of the most abundant species relative to the sampling locality was revealed. In the wooded areas Lutzomyia whitmani (Antunes & Coutinho) predominated, whereas in the urban area Lutzomyia longipalpis (Lutz & Neiva) was the most abundant species. These results indicate two possible epidemiological patterns of Leishmania transmission in Santa Luzia: one for American cutaneous leishmaniasis associated predominantly with wooded areas, and another for AVL, with transmission principally occurring around human habitations.

  7. Spatial and temporal distributions of phlebotomine sand flies (Diptera: Psychodidae), vectors of leishmaniasis, in Iran.

    Science.gov (United States)

    Karimi, Ameneh; Hanafi-Bojd, Ahmad Ali; Yaghoobi-Ershadi, Mohammad Reza; Akhavan, Amir Ahmad; Ghezelbash, Zahra

    2014-04-01

    Leishmaniasis is a major vector-borne disease and health problem in Iran. Studies on sand flies, as the vectors of the disease, began in the Northern and Western parts of the country in 1930 and have been continued up to now. Concerning many published information in the field of sand flies, providing a digital database for the country will help the public health authorities to make more correct and prompt decisions for planning leishmaniasis control programs as well as modeling and forecasting of transmission potential across the country. All published data on phlebotomine sand flies of Iran were collected. A database was then designed in Excel format, including all available information regarding sand flies. The valid data were transferred to ArcGIS9.3 to prepare the first spatial database of sand flies of Iran. The IrSandflybase includes 131 papers, 2 abstracts and 71 PhD/MSc theses, reporting studies conducted during 1930-2012. This database contains different available data covering all aspects of ecology and biology of 50 sand fly species in two genera of Phlebotomus and Sergentomyia in the country. The temporal activity of sand flies is reported 9 months in warm regions of the southern part, while it may reduce to 7-8 months in central plateau or 4-5 months in cold areas of the northwest. Occasional studies reported rare species from the borderlines of Iran. It seems that changing the climate due to global warming may affect the spatial distribution of different species and expand it into the country, the issue that can be followed by an updated database.

  8. Phlebotomine Sand Flies (Diptera: Psychodidae) in Iran and their Role on Leishmania Transmission.

    Science.gov (United States)

    Yaghoobi-Ershadi, Mr

    2012-01-01

    Sand fly research has a long history in Iran beginning with the work of Adler, Theodor and Lourie in 1930 and followed by Mesghali's foundational taxonomic work on sand flies in 1943. Since then, research has been continued unabated throughout the country and official publications report the existence of at least 44 species of sand flies (26 of the genus Phlebotomus and 18 of genus Sergentomyia) in Iran. So far, seven Phlebotomus species and one Sergentomyia species have been collected and described by Iranian researchers for the first time. Natural promastigote infections have been repeatedly found in 13 species of sand flies and modern molecular techniques are used routinely to characterize Leishmania parasite isolates from endemic areas of cutaneous and visceral leishmaniasis. Because of anthropogenic environmental modifications or human population movements, data on phlebotomine sand flies should be regularly updated and verified at least every five years by fieldwork and taxonomy in foci of leishmaniasis, to incriminate vector species of relevance to the ecology of transmission and to support development and implementation of control programs.

  9. Phlebotomine Sand Flies (Diptera: Psychodidae in Iran and their Role on Leishmania Transmission

    Directory of Open Access Journals (Sweden)

    MR Yaghoobi-Ershadi

    2012-06-01

    Full Text Available Sand fly research has a long history in Iran beginning with the work of Adler, Theodor and Lourie in 1930 and followed by Mesghali’s foundational taxonomic work on sand flies in 1943. Since then, research has continued unabated throughout the country and official publications report the existence of at least 44 species of sand flies (26 of the genus Phlebotomus and 18 of genus Sergentomyia in Iran. So far, seven Phlebotomus species and one Sergentomyia species have been collected and described by Iranian researchers for the first time. Natural promastigote infection have been repeatedly found in 13 species of sand flies and modern molecular techniques are used routinely to characterize Leishmania parasite isolates from endemic areas of cutaneous and visceral leishmaniasis. Because of anthropogenic environmental modifications or human population movements, data on phlebotomine sand flies should be regularly updated and verified at least every five years by fieldwork and taxonomy in foci of leishmaniasis, to incriminate vector species of relevance to the ecology of transmission and to support development and implementation of control programs

  10. Phleboviruses associated with sand flies in arid bio-geographical areas of Central Tunisia.

    Science.gov (United States)

    Dachraoui, K; Fares, W; Bichaud, L; Barhoumi, W; Beier, J C; Derbali, M; Cherni, S; Lamballerie, X de; Chelbi, I; Charrel, R N; Zhioua, E

    2016-06-01

    An entomological investigation was carried out in 2014 at two sites located in Central Tunisia, one irrigated and another non-irrigated situated in arid bio-geographical areas. Sand flies of the subgenus Larroussius namely Phlebotomus perfiliewi, Phlebotomus perniciosus, and Phlebotomus longicuspis are the most abundant sand fly species in the irrigated site. However, in the non-irrigated site, Phlebotomus papatasi of the Phlebotomus genus is the most abundant species. A total of 3191 sand flies were collected and pooled with up to 30 specimens per pool based on sex, trapping location and collection date, were tested for the presence of phleboviruses by nested reverse transcriptase polymerase chain reaction in the polymerase gene and sequenced. Of a total of 117 pools, 4 were positive, yielding a minimum infection rate of sand flies with phleboviruses of 0.12%. Phylogenetic analysis performed using partial nucleotide and amino acid sequence in the polymerase gene showed that these phleboviruses belonged to four different clusters corresponding to Toscana virus (TOSV), Saddaguia virus (SADV), Sandfly Fever Sicilian Virus (SFSV) and Utique virus (UTIV). This study provides more evidence that the abundance of P. perfiliewi is associated with the development of irrigation in arid bio-geographical areas of Central Tunisia which may have led to the emergence of phleboviruses. We report the first detection of TOSV from sand flies collected from Central Tunisia.

  11. Strength Properties of Fly Ash Based Geopolymer Concrete with Sea Sand

    Directory of Open Access Journals (Sweden)

    B. H. Shinde

    2016-07-01

    Full Text Available The production of every ton of cement contributes to production of one ton of CO2. With the development of infra activities, the power sector activities are also increasing. The coal based power plant produces huge quantity of fly ash, which creates its disposal problems. However to some extent, the fly ash is used as partial substitution to cement. The alkali activated fly ash concrete (Geopolymer Concrete proposed by Devidovits, shows considerable promise for application in construction industry as an alternative to the portland cement for precast concrete. Day by day the scarcity of river sand is big problem arrising to construction industry. On the other hand the sea sand is availibile in huge quantity, but the presence of salt and chloride affects strength and durability of cement concrete. In present experimental work the sea sand (Treated and untreated is used as an alternative to river sand and studied the properties of cement concrete and geopolymer concrete. The results show that the untreated sea sand affects the compressive strength in geopolymer concrete same as cement concrete but treated sea sand gives similar results as of river sand concrete

  12. Sand fly fauna in Chapare, Bolivia: an endemic focus of Leishmania (Viannia) braziliensis.

    Science.gov (United States)

    Bustamante, Marinely; Diaz, Mery; Espinoza, Jorge; Parrado, Rudy; Reithinger, Richard; García, Ana Lineth

    2012-09-01

    Data on the distribution and abundance of Lutzomyia spp. (Diptera: Psychodidae) in Bolivia is scarce. Sand flies from an area of Leishmania (Viannia) braziliensis endemicity in the Isiboro-Secure National Park in the Department of Cochabamba were captured and identified to species. In total, 945 sand flies (789 females and 156 males) belonging to 15 species were collected from the four collection points in two study villages in 2007. With 549 (58.1%) specimens, Lutzomyia shawi was the most abundant species, followed by Lutzomyia (Trichophoromyia) sp. (22.2%), Lutzomyia llanosmartinsi (8.3%), Lutzomyia antunesi (4.3%), and Lutzomyia olmeca (2.1%). Abundance and species composition varied between rainy and dry seasons, with 99.3% of all sand flies being collected outdoors. Because of species abundance and confirmed Leishmania infection in previous entomological collections, we believe Lu. shawi is the vector of L. (Viannia) braziliensis in Isiboro-Secure National Park.

  13. Synanthropy of mosquitoes and sand flies near the Aimorés hydroelectric power plant, Brazil.

    Science.gov (United States)

    Barata, R A; Ursine, R L; Nunes, F P; Morais, D H; Araújo, H S

    2012-12-01

    The environmental changes resulting from the construction of hydroelectric dams may affect the fauna of insect vectors and consequently the epidemiology of the diseases they transmit. This work examined the mosquito and sand fly fauna in the area of the Aimorés hydroelectric power plant, analyzing the seasonal distribution and the degree of species synanthropy in different ecotopes. Between November, 2008 and September, 2009, entomological captures were performed with the help of HP light traps in the rural, urban, and forest areas of Aimorés, Ituêta, Resplendor, and Baixo Guandu counties. The fauna proved to be quite diversified. Twenty-two species of mosquitoes and 11 species of sand flies were found. Culex quinquefasciatus was predominant among mosquitoes (76.7%), while Lutzomyia intermedia prevailed among sand flies (34.5%). Some of the captured species have medical interest. Supported by the high degree of synanthropy, those species reinforce the need for epidemiological surveillance.

  14. The First Report of Eustigmaeus Johnstoni (Acari: Stigmaeidae Parasitic Mite of Phlebotominae Sand Flies from Iran

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    Mehdi Badakhshan

    2013-03-01

    Full Text Available Background: Stigmaeids mites have been recorded only on Phlebotominae sand flies up to now. Five species of Eustigmaeus, and three of Stigmaeus were reported on infested sandflies in different country up to the present.Methods: Sand flies collection was done using CDC light trap and sticky paper. The mites were isolated from in­fested specimens, mounted in Puri’s medium and identified using reliable keys.Results: A mite infested Phlebotomus papatasi was observed during a study on sandflies of one of the southern provinces of Iran, near to the Persian Gulf. Several scars resulting from mite attachment were found on abdominal tergites of this female sand fly. The mites were identified as Eustigmaeus johnstoni.Conclusion: This parasitic mite is one of the eyeless species, which has a great distribution over the world, reported from Tunisia, Saudi Arabia, Pakistan, Yemen, Cyprus and Palestine. But, this is the first record of this species from Iran.

  15. Oral treatment of rodents with insecticides for control of sand flies (Diptera: Psychodidae) and the fluorescent tracer technique (FTT) as a tool to evaluate potential sand fly control methods.

    Science.gov (United States)

    Mascari, T M; Clark, J; Gordon, S; Mitchell, M A; Rowton, E D; Stout, R; Foil, L D

    2011-03-01

    In laboratory studies, insecticides (diflubenzuron, novaluron, methoprene and, pyriproxyfen) that have been incorporated into rodent diets were effective as feed-throughs against sand fly larvae. Novaluron also was effective against sand fly larvae at low concentrations and under simulated field conditions. Ivermectin has been shown to be effective as a systemic insecticide, killing 100% of blood-feeding sand flies for up to seven d after rodents were treated. The fluorescent tracer technique (FTT) is the use of certain fluorescent dyes (rhodamine B or uranine O) as feed-through transtadial biomarkers for phlebotomine sand flies, systemic biomarkers for blood-feeding sand flies, and permanent markers for nectar-feeding sand flies. The results of these laboratory studies provide proof of concept for the FTT and indicate that the FTT could be used to delineate specific foci with rodent/sand fly associations that would be susceptible to control by using feed-through or systemic insecticides, or foci where insecticide-treated sugar baits could be used against sand flies.

  16. Comparison of LAMP and PCR for molecular mass screening of sand flies for Leishmania martiniquensis infection

    Science.gov (United States)

    Tiwananthagorn, Saruda; Kato, Hirotomo; Yeewa, Ranchana; Muengpan, Amontip; Polseela, Raxsina; Leelayoova, Saovanee

    2017-01-01

    BACKGROUND Leishmaniasis caused by Leishmania martiniquensis infection has been reported in human and domestic animals of Martinique Island, Germany, Switzerland, USA, Myanmar and Thailand. The peculiar clinical features of disseminated cutaneous and visceral forms co-existence render the urgent need of specific diagnostic tool to identify the natural sand fly vectors for effective prevention and control strategies. Loop-mediated isothermal amplification (LAMP) of 18S rRNA gene as well as polymerase chain reaction (PCR) of minicircle kinetoplast DNA gene (PCR-mkDNA) have never been applied to detect L. martiniquensis and L. siamensis in sand fly vectors. OBJECTIVE The present study was aimed to validate malachite green-LAMP (MG-LAMP) and PCR-mkDNA techniques to detect L. martiniquensis in sand fly vectors, compared with the conventional PCR of internal transcribed spacer 1 (PCR-ITS1). METHODS We compared the validity of LAMP of 18S rRNA gene and PCR-mkDNA, to PCR-ITS1 in simulation model of L. martiniquensis infection in Sergentomyia gemmea sand flies. Attributable to the sensitivity and specificity, PCR-mkDNA was consecutively applied to detect L. martiniquensis in 380 female sand fly individuals captured in the newly identified affected region of Lamphun Province, Thailand. FINDINGS AND MAIN CONCLUSIONS Results showed that PCR-mkDNA could detect at least one promastigote per sand fly, which was 10-time superior to LAMP and PCR-ITS1. In addition, PCR-mkDNA was more specific, able to differentiate L. martiniquensis from other viscerotropic Leishmania species, such as L. siamensis, L. (L.) donovani, and L. (L.) infantum. Consecutively, mass screening of L. martiniquensis in 380 female sand fly individuals by PCR-mkDNA was implemented in a new affected area of Thailand where a patient with leishmaniasis/HIV co-infection resides; however Leishmania DNA was undetected. In conclusion, PCR-mkDNA is a promising tool for molecular mass screening of L. martiniquensis

  17. Acetylcholinesterase of the Sand Fly Phlebotomus papatasi (Scopoli): cDNA Sequence, Baculovirus Expression and Biochemical Properties

    Science.gov (United States)

    Millions of people and domestic animals around the world are affected by leishmaniasis, a disease caused by various species of flagellated protozoans in the genus Leishmania that are transmitted by several sand fly species. Insecticides are widely used for sand fly population control to try to reduc...

  18. Description of Pintomyia (Pifanomyia falcaorum sp. n. (Diptera: Psychodidae: Phlebotominae, a Fossil Sand Fly from Dominican Amber

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    Reginaldo Peçanha Brazil

    2002-06-01

    Full Text Available A new species of sand fly, Pintomyia (Pifanomyia falcaorum is described from an amber originated from the northern mountain range of Dominican Republic. The male sand fly specimen is well preserved and most features used in Phlebotominae taxonomy are seen with remarkable clarity.

  19. Natural breeding places for phlebotomine sand flies (Diptera: psychodidae) in a semiarid region of bahia state, Brazil.

    Science.gov (United States)

    Sangiorgi, Bruno; Miranda, Daniel Neves; Oliveira, Diego Ferreira; Santos, Edivaldo Passos; Gomes, Fernanda Regis; Santos, Edna Oliveira; Barral, Aldina; Miranda, José Carlos

    2012-01-01

    Few microhabitats have been previously identified as natural breeding places for phlebotomine sand flies so far, and little is known about the influence of climate variables in their density. The present study was conducted in a dry region with a semiarid climate, where visceral leishmaniasis occurs in humans and dogs. The occurrence of breeding places in specific microhabitats was investigated in soil samples collected from five houses, which were also the location used for sampling of adults. All the microhabitats sampled by our study were identified as natural breeding places due to the occurrence of immature forms of sand flies. On a weekly basis, the number of adult sand flies captured was positively correlated with the mean temperature from preceding weeks. These results, in addition to promoting an advance in the knowledge of sand flies biology, may furnish a tool for optimizing the control of the sand flies, by indicating the most suitable periods and microhabitats for the application of insecticides.

  20. Modification of Disney trap for capture of sand flies (Diptera: Psychodidae: Phlebotominae

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    Maria Elizabeth C Dorval

    2007-11-01

    Full Text Available This paper describes the modifications made to the original model of the Disney trap, with a view to easier handling of the same, greater practicability in the collection of sand flies, protection of the animal bait and durability of the trap in the field.

  1. Insecticide Treated Camouflage Sceening Reduces Sand Fly Numbers in Leishmania-Endemic Regions in Kenya

    Science.gov (United States)

    Current U.S. military operations in deserts face persistent threats from sand flies that transmit human Leishmania. In this study we investigated the efficacy of artificial barriers treated with residual insecticide to potentially reduce the risk of human infection from leishmaniasis by reducing the...

  2. Richness and diversity of sand flies (Diptera, Psychodidae) in an Atlantic rainforest reserve in southeastern Brazil.

    Science.gov (United States)

    Pinto, Israel Souza; Dos Santos, Claudiney Biral; Ferreira, Adelson Luiz; Falqueto, Aloísio

    2010-12-01

    Our objective was to study and evaluate the richness and diversity of Phlebotominae fauna in the Duas Bocas Biological Reserve (DBBR) in the state of Espírito Santo, in southeastern Brazil. Sand fly collections were carried out during four consecutive nights each month between August 2007 and July 2008 at DBBR by using CDC automatic light traps and an illuminated Shannon trap. Specific richness (S) and Shannon diversity index (H) was calculated for each trap. We collected 18,868 sand flies belonging to 29 species and 13 genera. Nyssomyia yuilli yuilli was the most abundant species followed by Psychodopygus ayrozai, Ps. hirsutus, Psathyromyia pascalei, and Ps. matosi. We recorded Brumptomyia cardosoi, Br. troglodytes, and Ps. geniculatus for the first time in the state of Espírito Santo. We discuss the differences in diversity and richness of the sand flies in both traps and in relation to other Brazilian localities and biomes. We also discuss the possibility of wild transmission of Leishmania in the DBBR and the influence of the sand fly species in leishmaniasis transmission to the adjacent areas of the reserve.

  3. Phlebotomine sand flies (Diptera: Psychodidae) transmitting visceral leishmaniasis and their geographical distribution in China: a review.

    Science.gov (United States)

    Guan, Li-Ren; Zhou, Zheng-Bin; Jin, Chang-Fa; Fu, Qing; Chai, Jun-Jie

    2016-02-23

    After the existence of phlebotomine sand flies was first reported in China in 1910, the distribution of different species and their role in the transmission of visceral leishmaniasis (VL) have been extensively studied. Up until 2008, four species have been verified as vectors of VL, namely, Phlebotomus chinensis (Ph. sichuanensis), Ph. longiductus (Ph. chinensis longiductus), Ph. wui (Ph. major wui), and Ph. alexandri. The sand fly species vary greatly depending on the natural environments in the different geographic areas where they are endemic. Ph. chinensis is euryecious and adaptable to different ecologies, and is thus distributed widely in the plain, mountainous, and Loess Plateau regions north of the Yangtze River. Ph. longiductus is mainly distributed in ancient oasis areas south of Mt. Tianshan in the Xinjiang Uygur autonomous region. Ph. wui is the predominant species in deserts with Populus diversifolia and Tamarix vegetation in Xinjiang and the western part of the Inner Mongolia autonomous region. Finally, Ph. alexandri is steroecious and found only in stony desert areas, such as at the foot of the mountains in Xinjiang and the western Hexi Corridor, in Gansu province. This review summarized the relationship between the geographic distribution pattern of the four sand fly species and their geographical landscape in order to foster research on disease distribution and sand fly control planning. Furthermore, some problems that remained to be solved about vectors of VL in China were discussed.

  4. Sand Fly Surveillance and Control on Camp Ramadi, Iraq, as Part of a Leishmaniasis Control Program

    Science.gov (United States)

    2013-12-01

    Santos De-Marco et al. 2002). Moon illumination and other environmental factors, such as temperature and wind speed, also affect sand fly behavior...the U.S. government as part of that person’s official duties. REFERENCES CITED Alexander, B. 2000. Sampling methods for phlebotomine sandflies . Med

  5. The seasonal abundance of phlebotomine sand flies, Lutzomyia species in Florida.

    Science.gov (United States)

    Mann, Rajinder S; Kaufman, Phillip E

    2010-03-01

    The seasonality of phlebotomine sand flies was studied in Florida, utilizing colored light-emitting diode- and attractant-baited Mosquito Magnet MM-X traps from September 2006 to September 2008 at San Felasco Hammock Preserve State Park, Gainesville, FL. A total of 6,278 sand flies were collected from 314 actual nights and 1,692 total trap-nights, yielding 3.7 sand flies per trap-night. Lutzomyia shannoni was the predominant species, constituting 55% to 80% of the total sand fly populations collected during the studies. Both L. shannoni and L. vexator populations were highly seasonal and were moderately influenced by weather factors. Lutzomyia shannoni populations peaked in May and showed reduced activity during December, January, and February. This species was active throughout the year and showed positive and negative correlations with average monthly temperature and relative humidity, respectively. Lutzomyia vexator showed peak activity during August and October with an activity lull from December to March. This species showed a positive correlation with average monthly temperature. No correlations were observed with either species for average daily, weekly, or 1- to 8-wk-lagging precipitation, number of rainy days, wind speed, or lunar phases. Lutzomyia shannoni abundance was weakly correlated to L. vexator abundance. No other Lutzomyia spp. were collected during the study.

  6. The effect of temperature on Leishmania (Kinetoplastida: Trypanosomatidae) development in sand flies.

    Science.gov (United States)

    Hlavacova, J; Votypka, J; Volf, P

    2013-09-01

    The spread of leishmaniasis to areas where it was previously considered nonendemic has been recently found in the New and Old Worlds, and climate changes are suspected as a crucial factor responsible for this spread. Ambient temperature is known to significantly affect the metabolism of sand flies and their developmental times, but little is known about the effect of temperature on the Leishmania life cycle in vectors. This study assesses the effect of temperature on the development of two closely related New World Viannia species, Leishmania braziliensis and Leishmania peruviana, in the permissive vector Lutzomyia longipalpis, and on the development of New and Old World Leishmania infantum in its natural vectors Lu. longipalpis and Phlebotomus perniciosus, respectively. The mountain species L. peruviana developed well in sand fly females kept at 20 degrees C, whereas at 26 degrees C, most infections were lost during the defecation ofbloodmeal remains; this suggests an adaptation to the slower metabolism of sand flies living at lower ambient temperature. On the contrary, L. infantum and L. braziliensis developed well at both temperatures tested; heavy late-stage infections were observed in a majority of sand fly females maintained at 20 degrees C as well 26 degrees C. Frequent fully developed infections of L. infantum and L. braziliensis at 20 degrees C suggest a certain risk of the spread of these two Leishmania species to higher latitudes and altitudes.

  7. Infectivity of seropositive dogs, showing different clinical forms of leishmaniasis, to Lutzomyia longipalpis phlebotomine sand flies.

    Science.gov (United States)

    Michalsky, Erika Monteiro; Rocha, Marília Fonseca; da Rocha Lima, Ana Cristina Vianna Mariano; França-Silva, João Carlos; Pires, Marize Quinhone; Oliveira, Fernanda Santos; Pacheco, Raquel Silva; dos Santos, Sara Lopes; Barata, Ricardo Andrade; Romanha, Alvaro José; Fortes-Dias, Consuelo Latorre; Dias, Edelberto Santos

    2007-06-20

    Visceral leishmaniasis (VL) is a growing zoonosis with an increasing number of new cases and a rapid geographical spreading of the disease. In the present study, a canine survey was carried out in the city of Montes Claros (320,000 inhabitants), an endemic area of American visceral leishmaniasis in the state of Minas Gerais, Brazil. A total number of 4795 dogs were examined by serology, which showed a rate of seropositivity of 5%. Isoenzymatic analysis confirmed Leishmania infantum chagasi as the local aetiological agent of CVL. Canine tissues were assayed for the presence of Leishmania parasite DNA using different techniques. The infectivity of asymptomatic, oligosymptomatic and symptomatic seropositive dogs was tested by xenodiagnosis using laboratory reared Lutzomyia longipalpis. Rates of infection of 5.4%, 5.1% and 28.4% were found for the phlebotomine sand flies that fed in asymptomatic, oligosymptomatic and symptomatic dogs, respectively. Our results indicate that, under experimental conditions, symptomatic dogs are about four times more infective to VL vectors than oligosymptomatic or asymptomatic animals. The lower infectivity rates of dogs displaying any of the last two clinical forms of leishmaniasis, however, must be taken into account in the epidemiology of CVL.

  8. Xenodiagnosis on dogs with visceral leishmaniasis: Canine and sand fly aspects related to the parasite transmission.

    Science.gov (United States)

    Magalhães-Junior, Jairo Torres; Mota, Tiago Feitosa; Porfirio-Passos, Gabriela; Larangeira, Daniela Farias; Franke, Carlos Roberto; Barrouin-Melo, Stella Maria

    2016-06-15

    One of the main limitations for the effective control of canine leishmaniasis in endemic areas is the difficulty in identifying infectious dogs. The objective of this study was to determine factors, related to dogs and to parasite detection in sand flies, which are associated with the positive xenodiagnosis of Leishmania infantum using the vector Lutzomyia longipalpis. The xenodiagnosis was performed in 50 owned dogs residing in endemic areas, which were divided into three different groups: G1-26 dogs proved to be infected and classified by severity of VL clinical signs on physical examination; G2-15 dogs proved to be infected and classified by severity of clinical signs and intensity of laboratory abnormalities; G3-nine dogs that were seropositive for anti-Leishmania IgG in ELISA tests. Parasite search in the sand flies after having fed on dogs in the xenodiagnosis was performed by both methodologies, PCR and dissection followed by microscopy. In G1, 58% (15/26) of dogs were able to transmit Leishmania to the vector, when parasite detection in sand flies were performed by PCR technique, 5 days after blood meal, whereas in G2, 53% (8/15) transmitted the parasite to the vector, however, confirmation was performed by direct observation of parasite through optical miscroscopy held 10 days after blood meal. Rate of infectiousness of dogs to sand flies was positively associated to severity of disease (p=0.042 and p=0.040), regardless the method used for clinical classification or for parasite detection in sand flies after xenodiagnosis. In G1 30% (3/10) of dogs with subclinical infection were infectious to the vector, while 80% (12/16) of dogs with clinical disease were also infectious. Even more, 17% (1/6) of dogs that had moderate disease were infectious to the sand flies, while 78% (7/9) of dogs with severe disease were infectious in G2. Still in G2, the proportion of sand flies infected (grade of infectiousness) was significantly lower (p=0.0098) when they fed on

  9. Natural infections of man-biting sand flies by Leishmania and Trypanosoma species in the northern Peruvian Andes.

    Science.gov (United States)

    Kato, Hirotomo; Gomez, Eduardo A; Cáceres, Abraham G; Vargas, Franklin; Mimori, Tatsuyuki; Yamamoto, Kento; Iwata, Hiroyuki; Korenaga, Masataka; Velez, Lenin; Hashiguchi, Yoshihisa

    2011-05-01

    The natural infection of sand flies by Leishmania species was studied in the Andean areas of Peru where cutaneous leishmaniasis caused by Leishmania (Viannia) peruviana is endemic. Sand flies were captured by human bait and Center for Disease Control (CDC) light trap catches at Nambuque and Padregual, Department of La Libertad, Peru, and morphologically identified. Among 377 female sand flies dissected, the two dominant man-biting species were Lutzomyia (Helcocyrtomyia) peruensis (211 flies) and Lutzomyia (Helcocyrtomyia) caballeroi (151 flies). Another sand fly species captured by light trap was Warileya phlebotomanica (15 flies). The natural infection of sand flies by flagellates was detected in 1.4% of Lu. (H.) peruensis and 2.6% of Lu. (H.) caballeroi, and the parasite species were identified as Le. (V.) peruviana and Trypanosoma avium, respectively, by molecular biological methods. The results indicated that the vector species responsible for the transmission of leishmaniasis in the study areas is Lu. (H.) peruensis. In addition, the presence of Trypanosoma in man-biting sand fly species means that more careful consideration is necessary for vector research in areas of Andean Peru where leishmaniasis is endemic.

  10. Sand fly fauna (Diptera: Psychodidae: Phlebotominae) in an area of leishmaniasis transmission in the municipality of Rio Branco, state of Acre, Brazil

    OpenAIRE

    de Araujo-Pereira, Thais; Fuzari, Andressa A; Filho, José Dilermado Andrade; de Pita-Pereira, Daniela; Britto, Constança; Reginaldo P Brazil

    2014-01-01

    Background Notifications concerning American Cutaneous Leishmaniasis have increased in recent years in the state of Acre, Brazil. Despite identification of distinct Leishmania species isolated from cutaneous lesions, there are still no records of visceral leishmaniasis in the state. However, studies on the sand fly fauna in this region are still limited. Findings Insects were collected from April 2011 to April 2012, using HP light traps distributed in four residential areas and one recreation...

  11. Optimization of fly ash as sand replacement materials (SRM) in cement composites containing coconut fiber

    Science.gov (United States)

    Nadzri, N. I. M.; Jamaludin, S. B.; Mazlee, M. N.; Jamal, Z. A. Z.

    2016-07-01

    The need of utilizing industrial and agricultural wastes is very important to maintain sustainability. These wastes are often incorporated with cement composites to improve performances in term of physical and mechanical properties. This study presents the results of the investigation of the response of cement composites containing coconut fiber as reinforcement and fly ash use as substitution of sand at different hardening days. Hardening periods of time (7, 14 and 28 days) were selected to study the properties of cement composites. Optimization result showed that 20 wt. % of fly ash (FA) is a suitable material for sand replacement (SRM). Meanwhile 14 days of hardening period gave highest compressive strength (70.12 MPa) from the cement composite containing 9 wt. % of coconut fiber and fly ash. This strength was comparable with the cement without coconut fiber (74.19 MPa) after 28 days of curing.

  12. Insecticide resistance in the sand fly, Phlebotomus papatasi from Khartoum State, Sudan

    Directory of Open Access Journals (Sweden)

    Hassan Mo'awia

    2012-03-01

    Full Text Available Abstract Background Phlebotomus papatasi the vector of cutaneous leishmaniasis (CL is the most widely spread sand fly in Sudan. No data has previously been collected on insecticide susceptibility and/or resistance of this vector, and a first study to establish a baseline data is reported here. Methods Sand flies were collected from Surogia village, (Khartoum State, Rahad Game Reserve (eastern Sudan and White Nile area (Central Sudan using light traps. Sand flies were reared in the Tropical Medicine Research Institute laboratory. The insecticide susceptibility status of first progeny (F1 of P. papatasi of each population was tested using WHO insecticide kits. Also, P. papatasi specimens from Surogia village and Rahad Game Reserve were assayed for activities of enzyme systems involved in insecticide resistance (acetylcholinesterase (AChE, non-specific carboxylesterases (EST, glutathione-S-transferases (GSTs and cytochrome p450 monooxygenases (Cyt p450. Results Populations of P. papatasi from White Nile and Rahad Game Reserve were sensitive to dichlorodiphenyltrichloroethane (DDT, permethrin, malathion, and propoxur. However, the P. papatasi population from Surogia village was sensitive to DDT and permethrin but highly resistant to malathion and propoxur. Furthermore, P. papatasi of Surogia village had significantly higher insecticide detoxification enzyme activity than of those of Rahad Game Reserve. The sand fly population in Surogia displayed high AChE activity and only three specimens had elevated levels for EST and GST. Conclusions The study provided evidence for malathion and propoxur resistance in the sand fly population of Surogia village, which probably resulted from anti-malarial control activities carried out in the area during the past 50 years.

  13. Efficacy of commercial mosquito traps in capturing phlebotomine sand flies (Diptera: Psychodidae) in Egypt.

    Science.gov (United States)

    Hoel, D F; Kline, D L; Hogsette, J A; Bernier, U R; El-Hossary, S S; Hanafi, H A; Watany, N; Fawaz, E Y; Furman, B D; Obenauer, P J; Szumlas, D E

    2010-11-01

    Four types of commercial mosquito control traps, the Mosquito Magnet Pro (MMP), the Sentinel 360 (S360), the BG-Sentinel (BGS), and the Mega-Catch Ultra (MCU), were compared with a standard Centers for Disease Control and Prevention (CDC) light trap for efficacy in collecting phlebotomine sand flies (Diptera: Psychodidae) in a small farming village in the Nile River Valley 10 km north of Aswan, Egypt. Each trap was baited with either carbon dioxide (CO2) from combustion of butane gas (MMP), dry ice (CDC and BGS traps), light (MCU and S360), or dry ice and light (CDC). Traps were rotated through five sites in a5 x 5 Latin square design, repeated four times during the height of the sand fly season (June, August, and September 2007) at a site where 94% of sand flies in past collections were Phlebotomus papatasi (Scopoli). A total of 6,440 sand flies was collected, of which 6,037 (93.7%) were P. papatasi. Of the CO2-baited traps, the BGS trap collected twice as many P. papatasi as the MMP and CDC light traps, and at least three times more P. papatasi than the light-only MCU and S360 traps (P MMP 56.8 (+/- 9.0) > CDC 52.3 (+/- 6.1) > MCU 38.2 (+/- 6.4) > S360 12.6 (+/- 1.8). Results indicate that several types of commercial traps are suitable substitutes for the CDC light trap in sand fly surveillance programs.

  14. Diversity of phlebotomine sand flies (Diptera: Psychodidae) in Ibitipoca State Park, Minas Gerais, Brazil.

    Science.gov (United States)

    Carvalho, Gustavo Mayr de Lima; De Vasconcelos, Fernanda Bernardes; Da Silva, Daniela Gonçalves; Botelho, Helbert Antônio; Filho, José Dilermando Andrade

    2011-07-01

    Leishmaniasis is a complex of zoonotic diseases that are endemic to many Brazilian states. They are transmitted to the vertebrates by the bite of the hematophagous female sand fly (Diptera: Psychodidae) vectors. Despite the increasing occurrence of visceral and cutaneous leishmaniasis cases in large urban centers, their transmission continues to occur primarily in a wild environment and may be associated with professional activities, ecotourism activities, or both. This study investigates the ecological parameters of the sand flies present in Ibitipoca State Park, Minas Gerais, Brazil. During 2009, systematic collections of sand flies were made monthly using HP light traps installed at five sites, including three natural settings (a cave, riparian vegetation, and a rain forest), the tourist and researchers' accommodations, and a surrounding domestic livestock area. In total, 161 sand flies (seven species) were collected, the most abundant, particularly in the surrounding domestic livestock area, being Lutzomyia (Psychodopygus) lloydi (Antunes, 1937). Furthermore, a previously unidentified Lutzomyia (Sciopemyia) sp. was prevalent in the cave environment. There are no existing records of the occurrence of leishmaniasis in Ibitipoca State Park; however, the some species of the subgenus Psychodopygus are known vectors of Leishmania spp in Brazil. Hence, the presence of a species of this genus in areas surrounding the park may represent a risk to ecotourism and the local inhabitants. Our study shows the importance of regular monitoring of the various areas used by humans to determine the distribution and spread of sand fly vectors for preventive management to forestall potential risk to health and consequent effect on ecotourists.

  15. SandflyMap: leveraging spatial data on sand fly vector distribution for disease risk assessments

    Directory of Open Access Journals (Sweden)

    Desmond H. Foley

    2012-09-01

    Full Text Available We feature SandflyMap (www.sandflymap.org, a new map service within VectorMap (www.vectormap.org that allows free public online access to global sand fly, tick and mosquito collection records and habitat suitability models. Given the short home range of sand flies, combining remote sensing and collection point data give a powerful insight into the environmental determinants of sand fly distribution. SandflyMap is aimed at medical entomologists, vector disease control workers, public health officials and health planners. Data are checked for geographical and taxonomic errors, and are comprised of vouchered specimen information, and both published and unpublished observation data. SandflyMap uses Microsoft Silverlight and ESRI’s ArcGIS Server 10 software platform to present disease vector data and relevant remote sensing layers in an online geographical information system format. Users can view the locations of past vector collections and the results of models that predict the geographic extent of individual species. Collection records are searchable and downloadable, and Excel collection forms with drop down lists, and Excel charts to country, are available for data contributors to map and quality control their data. SandflyMap makes accessible, and adds value to, the results of past sand fly collecting efforts. We detail the workflow for entering occurrence data from the literature to SandflyMap, using an example for sand flies from South America. We discuss the utility of SandflyMap as a focal point to increase collaboration and to explore the nexus between geography and vector-borne disease transmission.

  16. Laboratory Validation of the Sand Fly Fever Virus Antigen Assay

    Science.gov (United States)

    2015-12-01

    TOSV), sandfly fever Sicilian virus (SFSV), sandfly fever Naples virus (SFNV), and Punta Toro virus (Tesh 1988, Alkan et al. 2013). These viruses pose a...SFFVA against arthropod- borne phleboviruses that are not members of the SF virus group (Heartland viruses ) or are members of the SF virus group but not...less virus in wild infected flies. The proprietary grinding solution provided with the kit will inactivate most arbo- viruses , preventing them

  17. 76 FR 26654 - Movement of Hass Avocados From Areas Where Mediterranean Fruit Fly or South American Fruit Fly Exist

    Science.gov (United States)

    2011-05-09

    ... Avocados From Areas Where Mediterranean Fruit Fly or South American Fruit Fly Exist AGENCY: Animal and... from Mediterranean fruit fly quarantined areas in the United States with a certificate if the fruit is... quarantine regulations to remove trapping requirements for Mediterranean fruit fly for Hass avocados...

  18. 76 FR 18419 - Movement of Hass Avocados From Areas Where Mediterranean Fruit Fly or South American Fruit Fly Exist

    Science.gov (United States)

    2011-04-04

    ... Movement of Hass Avocados From Areas Where Mediterranean Fruit Fly or South American Fruit Fly Exist AGENCY... Mediterranean fruit fly quarantined areas in the United States with a certificate if the fruit is safeguarded... quarantine regulations to remove trapping requirements for Mediterranean fruit fly for Hass avocados......

  19. 76 FR 43804 - Movement of Hass Avocados From Areas Where Mediterranean Fruit Fly or South American Fruit Fly Exist

    Science.gov (United States)

    2011-07-22

    ... Avocados From Areas Where Mediterranean Fruit Fly or South American Fruit Fly Exist AGENCY: Animal and... Mediterranean fruit fly quarantined areas in the United States with a certificate if the fruit is safeguarded... regulations to remove trapping requirements for Mediterranean fruit fly for Hass avocados imported from...

  20. Seasonal occurrence of phlebotominae sand flies (Phlebotominae: Diptera) and it's correlation with Kala-Azar in eastern Uttar Pradesh, India.

    Science.gov (United States)

    Singh, N S; Singh, Doris Phillips

    2009-05-01

    In this investigation, the species composition of sand flies, and their seasonality, nocturnal activity, sex ratio, and resting site, for implementation of future control measures, were surveyed in eastern (Gonda and Basti) Uttar Pradesh, India. Adult sand flies (2,893) were collected from internal and external sites by sticky and light traps. The sand flies were captured using light traps hung at different heights in trees and in peridomiciliary and extradomiciliary areas of a forest during both dry and rainy months. The traps were kept out between sunset and sunrise of the following day. In the extradomiciliary environment, the traps were installed at 1, 3 and 5 m above the ground. In this investigation, a total of 5 species were obtained: Phlebotomus papatasi, P. sergenti, Sergentomyia sintoni, S. punjabensis and S. dentata. The number of sand flies peaked in September and declined by December. The maximum and minimum numbers were found at 8:00 PM and 5:00 to 6:00 AM, respectively. The female to male ratio of the phlebotominae sand flies varied from a high in October to a low in June. The number of sand flies in the external regions was significantly more (p sand flies. Using the results of this investigation, health workers in this area may be better able to control and prevent leishmaniasis.

  1. Impact of Phlebotomine Sand Flies on U.S. Military Operations at Tallil Air Base, Iraq: 4. Detection and Identification of Leishmania Parasites in Sand Flies

    Science.gov (United States)

    2009-05-01

    l ofAEbufferwas added, followed by incubation at room temperature for 5 min and centrifugion at 8,000 rpm for 1 min in a microcentrifuge. An...additional 50 l of AE buffer was added to the QIAamp Spin Column, followed by in- cubation at room temperature for 5 min and centri- fugion at 8,000 rpm for...FLIES 653 addition, DNA from three species of phlebotomine sand ßies Lutzomyia longipalpis (Lutz and Neiva), P. papatasi, and Phlebotomus argentipes

  2. Natural breeding sites of phlebotomine sand flies (Diptera: Psychodidae) on Marambaia Island, Rio de Janeiro State, Brazil.

    Science.gov (United States)

    Souza, T L; Figueiredo, F B; Almeida, A B; Benigno, C V; Pontes, C S; Souza, M B

    2014-08-01

    Immature phlebotomine sand flies develop in soils with essential and ideal characteristics for their life cycle, such as organic matter, humidity, temperature and low levels of light. Information regarding the potential breeding places of these dipterans is fundamental to understand the epidemiology and ecology of leishmaniasis, in addition to its importance to control them. In the present study, we aimed to find natural breeding sites of sand flies on Marambaia Island with the aid of emergence traps and direct search of immature forms using the flotation technique with saturated sugar solution in organic substrates of the region. Both methods were effective, with a total of 42 specimens of six different species - including some species that participate in the transmission cycle of American Tegumentary Leishmaniasis - collected by the emergence traps, and five immature forms obtained by floatation technique. However, further studies are still necessary, mainly with respect to the ecology and biology of immature sandfly stages, so that control measures focused on breeding sites can produce positive sustainable results in natural environments.

  3. Differential Midgut Attachment of Leishmania (Viannia braziliensis in the Sand Flies Lutzomyia (Nyssomyia whitmani and Lutzomyia (Nyssomyia intermedia

    Directory of Open Access Journals (Sweden)

    Rodrigo P. Soares

    2010-01-01

    Full Text Available The interaction between Leishmania and sand flies has been demonstrated in many Old and New World species. Besides the morphological differentiation from procyclic to infective metacyclic promastigotes, the parasite undergoes biochemical transformations in its major surface lipophosphoglycan (LPG. An upregulation of β-glucose residues was previously shown in the LPG repeat units from procyclic to metacyclic phase in Leishmania (Viannia braziliensis, which has not been reported in any Leishmania species. LPG has been implicated as an adhesion molecule that mediates the interaction with the midgut epithelium of the sand fly in the Subgenus Leishmania. These adaptations were explored for the first time in a species from the Subgenus Viannia, L. (V. braziliensis with its natural vectors Lutzomyia (Nyssomyia intermedia and Lutzomyia (Nyssomyia whitmani. Using two in vitro binding techniques, phosphoglycans (PGs derived from procyclic and metacyclic parasites were able to bind to the insect midgut and inhibit L. braziliensis attachment. Interestingly, L. braziliensis procyclic parasite attachment was ∼11-fold greater in the midgut of L. whitmani than in L. intermedia. The epidemiological relevance of L. whitmani as a vector of American Cutaneous Leishmaniasis (ACL in Brazil is discussed.

  4. Molecular Detection of Leishmania in Sand Flies (Diptera: Psychodidae: Phlebotominae) Collected in the Caititu Indigenous Reserve of the Municipality of Lábrea, State of Amazonas, Brazil.

    Science.gov (United States)

    Silva, T R R; Assis, M D G; Freire, M P; Rego, F D; Gontijo, C M F; Shimabukuro, P H F

    2014-11-01

    Phlebotominae sand flies are of medical importance because they are vectors of human pathogens, such as protozoa of the genus Leishmania Ross, etiological agent of American cutaneous leishmaniasis (ACL). In Lábrea, a municipality in the state of Amazonas, Brazil, ACL is primarily associated with subsistence activities, such as collection and extraction of forest products, undertaken by both indigenous and nonindigenous people. Data on ACL in indigenous populations are scarce, such that there is little information on the identity of the etiologic agent(s), reservoir host(s) and insect vector(s). The aim of this work was to study the sand fly fauna collected during an 8-d surveillance of different habitats in the Indigenous Reserve Caititu, Lábrea. In total, 1,267 sand flies were collected in different habitats for eight consecutive days, of which 819 (64.6%) were females and 448 (35.4%) males, from 10 genera and 32 species. The most abundant genera were Psychodopygus (34.3%), Trichophoromyia (22.9%), and Nyssomyia (15.3%). The most abundant species were Trichophoromyia ubiquitalis (Mangabeira) (n = 235, 18.5%), Psychodopygus davisi (Root) (n = 228, 18.0%) and Nyssomyia antunesi (Coutinho) (n = 135, 10.7%). Direct sequencing of polymerase chain reaction products demonstrated the presence of Leishmania (Leishmania) amazonensis and Leishmania (Viannia) braziliensis in the following species of sand flies: Evandromyia apurinan (Shimabukuro, Silveira, & Silva), Nyssomyia umbratilis (Ward & Fraiha), Nyssomyia yuilli yuilli (Young & Porter), Ps. davisi, Sciopemyia servulolimai (Damasceno & Causey), and Th. ubiquitalis. The presence of natural infection by Leishmania detected in the sand fly species investigated in this study suggests their possible role in the transmission cycle of ACL in the studied area.

  5. The development of Leishmania turanica in sand flies and competition with L. major

    Directory of Open Access Journals (Sweden)

    Chajbullinova Alsu

    2012-10-01

    Full Text Available Abstract Background In Central Asian foci of zoonotic cutaneous leishmaniases, mixed infections of Leishmania turanica and L. major have been found in a reservoir host (the great gerbil, Rhombomys opimus as well as in the sand fly vector Phlebotomus papatasi, but hybrids between these two Leishmania species have never been reported. In addition, the role of sand fly species other than P. papatasi in L. turanica circulation is not clear. Methods In this work we compared the development of L. turanica in three sand fly species belonging to different subgenera. In addition, we studied experimental co-infections of sand flies by both Leishmania species using GFP transfected L. turanica (MRHO/MN/08/BZ18(GFP+ and RFP transfected L. major (WHOM/IR/-/173-DsRED(RFP+. The possibility of Leishmania genetic exchange during the vectorial part of the life cycle was studied using flow cytometry combined with immunofluorescent microscopy. Results Late-stage infections of L. turanica with frequent colonization of the stomodeal valve were observed in the specific vector P. (Phlebotomus papatasi and in the permissive vector P. (Adlerius arabicus. On the other hand, in P. sergenti (the specific vector of L. tropica, L. turanica promatigotes were present only until the defecation of bloodmeal remnants. In their natural vector P. papatasi, L. turanica and L. major developed similarly, and the spatiotemporal dynamics of localization in the sand fly gut was the same for both leishmania species. Fluorescence microscopy in combination with FACS analyses did not detect any L. major / L. turanica hybrids in the experimental co-infection of P. papatasi and P. duboscqi. Conclusion Our data provide new insight into the development of different leishmania parasite species during a mixed infection in the sand fly gut. Despite the fact that both Leishmania species developed well in P. papatasi and P. duboscqi and did not outcompete each other, no genetic exchange was found

  6. Species composition and activity patterns of sand flies (Psycodidae: Phlebotomine) in four tehsils of Dir Districts, Khyber Pakhtunkhwa, Pakistan.

    Science.gov (United States)

    Ali, Naheed; Khan, Khurshaid; Wahid, Sobia; Khan, Nazma Habib; Shah, Safeer Ullah

    2016-04-01

    The present study reports sand flies species composition, fauna diversity and seasonal variations from four tehsils of Dir Districts, Khyber Pakhtunkhwa, Pakistan. Collection was made using sticky traps, flit method and aspiration where highest number of sand flies was captured through sticky traps. Digitalized sand flies distribution maps were produced using geographic information system ArcGIS. A total of 7292 specimens were captured between January to December 2014, comprised of 11 Sergentomyia and 9 Phlebotomus. Phlebotomus salengensis was the most abundant species followed by Phlebotomus sergenti. Overall, male to female ratio observed was 3:1 and species diversity varied among the studied tehsils. Highest abundance was recorded in July and August, whereas the flies disappeared in the colder months (November-April) of the year. Information about insect vector behaviour in natural setting is required to understand the status of disease caused by them. This study is a thorough account of biodiversity of sand flies in the region and provides a useful insight in to identifying potential breeding preferences of sand flies and recognition of active and potential vector species in the Dir districts. Further large scale studies are needed to determine the behaviour, infection rate, and the natural reservoir hosts of sand fly vectors in the region.

  7. DNA Barcoding of Neotropical Sand Flies (Diptera, Psychodidae, Phlebotominae): Species Identification and Discovery within Brazil.

    Science.gov (United States)

    Pinto, Israel de Souza; Chagas, Bruna Dias das; Rodrigues, Andressa Alencastre Fuzari; Ferreira, Adelson Luiz; Rezende, Helder Ricas; Bruno, Rafaela Vieira; Falqueto, Aloisio; Andrade-Filho, José Dilermando; Galati, Eunice Aparecida Bianchi; Shimabukuro, Paloma Helena Fernandes; Brazil, Reginaldo Peçanha; Peixoto, Alexandre Afranio

    2015-01-01

    DNA barcoding has been an effective tool for species identification in several animal groups. Here, we used DNA barcoding to discriminate between 47 morphologically distinct species of Brazilian sand flies. DNA barcodes correctly identified approximately 90% of the sampled taxa (42 morphologically distinct species) using clustering based on neighbor-joining distance, of which four species showed comparatively higher maximum values of divergence (range 4.23-19.04%), indicating cryptic diversity. The DNA barcodes also corroborated the resurrection of two species within the shannoni complex and provided an efficient tool to differentiate between morphologically indistinguishable females of closely related species. Taken together, our results validate the effectiveness of DNA barcoding for species identification and the discovery of cryptic diversity in sand flies from Brazil.

  8. SAND FLY SPECIES COMPOSITION (DIPTERA: PSYCHODIDAE: PHLEBOTOMINAE IN THE MUNICIPALITY OF CANTAGALO , AN AREA WITH SPORADIC CASES OF HUMAN CUTANEOUS LEISHMANIASIS IN RIO DE JANEIRO STATE, BRAZIL

    Directory of Open Access Journals (Sweden)

    Quezia Nunes PERES-DIAS

    2016-01-01

    Full Text Available SUMMARY The municipality of Cantagalo is an area with sustained transmission of American Cutaneous Leishmaniasis (ACL. Monthly sand fly collections were performed for three years (June 2012 - May 2015 using a CDC light trap. A total of 3,310 specimens belonging to 12 species were trapped: Nyssomyia intermedia, Nyssomyia whitmani, Migonemyia migonei, Evandromyia lenti, Evandromyia cortelezzii, Micropygomyia quinquefer, Brumptomyia brumpti, Psathyromyia aragaoi, Micropygomyia schreiberi, Pintomyia fischeri, Sciopemyia sordellii, and Evandromyia edwardsi. The last seven species have not been previously recorded in this area. The highest abundance of species occurred between October and March. October was the month with the highest number of captured sand flies, one month before the peak in the summer rainfall. In October the highest number of Ny. intermedia, Ny. whitmani and Mg. migonei, were also collected, the three epidemiologically most important species. The high abundance of species with epidemiological importance for ACL transmission might explain the sporadic occurrence of the disease in the area.

  9. Ivermectin as a Rodent Feed-Through Insecticide for Control of Immature Sand Flies (Diptera: Psychodidae)

    Science.gov (United States)

    2008-01-01

    humidity and is protected from extreme temperatures . Adult sand flies live in close proximity to sources of blood (from the rodents living within the... temperature for 7 days and then were stored at 270uC until used. In each experiment, the body weight and daily food intake of hamsters in the 4 diet groups were...LN, Mamigonova RI, Sabatov EA. 1983. Use of D-20 aerosol insecticide smoke pots in controlling burrow sandflies . Med Parazitol Parazit Bolezni 4:78

  10. Influence of the Microenvironment in the Transcriptome of Leishmania infantum Promastigotes: Sand Fly versus Culture.

    Science.gov (United States)

    Alcolea, Pedro J; Alonso, Ana; Domínguez, Mercedes; Parro, Víctor; Jiménez, Maribel; Molina, Ricardo; Larraga, Vicente

    2016-05-01

    Zoonotic visceral leishmaniasis is a vector-borne disease caused by Leishmania infantum in the Mediterranean Basin, where domestic dogs and wild canids are the main reservoirs. The promastigote stage replicates and develops within the gut of blood-sucking phlebotomine sand flies. Mature promastigotes are injected in the dermis of the mammalian host and differentiate into the amastigote stage within parasitophorous vacuoles of phagocytic cells. The major vector of L. infantum in Spain is Phlebotomus perniciosus. Promastigotes are routinely axenized and cultured to mimic in vitro the conditions inside the insect gut, which allows for most molecular, cellular, immunological and therapeutical studies otherwise inviable. Culture passages are known to decrease infectivity, which is restored by passage through laboratory animals. The most appropriate source of promastigotes is the gut of the vector host but isolation of the parasite is technically challenging. In fact, this option is not viable unless small samples are sufficient for downstream applications like promastigote cultures and nucleic acid amplification. In this study, in vitro infectivity and differential gene expression have been studied in cultured promastigotes at the stationary phase and in promastigotes isolated from the stomodeal valve of the sand fly P. perniciosus. About 20 ng RNA per sample could be isolated. Each sample contained L. infantum promastigotes from 20 sand flies. RNA was successfully amplified and processed for shotgun genome microarray hybridization analysis. Most differentially regulated genes are involved in regulation of gene expression, intracellular signaling, amino acid metabolism and biosynthesis of surface molecules. Interestingly, meta-analysis by hierarchical clustering supports that up-regulation of 22.4% of the differentially regulated genes is specifically enhanced by the microenvironment (i.e. sand fly gut or culture). The correlation between cultured and naturally

  11. Phlebotomine sand flies (Diptera, Psychodidae from Rio de Janeiro State, Brazil: species distribution and potential vectors of leishmaniases

    Directory of Open Access Journals (Sweden)

    Bruno Moreira Carvalho

    2014-03-01

    Full Text Available Phlebotomine sand flies (Diptera, Psychodidae from Rio de Janeiro State, Brazil: Species distribution and potential vectors of leishmaniases. Rio de Janeiro State, in Brazil, has endemic areas of both cutaneous and visceral leishmaniases. In these areas, entomologic surveillance actions are highly recommended by Brazil's Ministry of Health. The present work describes the results of sand fly captures performed by the Health Department of Rio de Janeiro State between 2009 and 2011 in several municipalities. An updated species list and distribution of phlebotomine sand flies in the state are provided based on an extensive literature review. Currently, the sand fly fauna of Rio de Janeiro State has 65 species, belonging to the genera Brumptomyia (8 spp. and Lutzomyia (57 spp.. Distribution maps of potential leishmaniases vector species Lutzomyia (Nyssomyia intermedia, L. migonei, L. (N. whitmani, L. (N. flaviscutellata and L. (Lutzomyia longipalpis are provided and their epidemiological importance is discussed.

  12. Phlebotomine sand flies (Diptera: Psychodidae: Phlebotominae) in urban rainforest fragments, Manaus -- Amazonas State, Brazil.

    Science.gov (United States)

    da Rocha, Liliane Coelho; de Freitas, Rui Alves; Franco, Antonia Maria Ramos

    2013-05-01

    The non-flooded upland rainforest fragment in the Federal University of Amazonas Campus is considered one of the world's largest urban tropical woodland areas and Brazil's second largest one in an urban setting. It is located in the city of Manaus, State of Amazonas at 03° 04' 34″ S, 59° 57' 30″ W, in an area covering nearly 800 hectares. Forty-one (41) sand fly species belonging to genus Lutzomyia were found attaining a total of 4662 specimens collected. Lutzomyia umbratilis was the dominant species at all heights, followed by Lutzomyia anduzei and Lutzomyia claustrei. The fauna alpha diversity index showed to be 6.4, which is not much lower than that reported for areas of continuous forest in this Amazonian region. This data provides additional evidence on Phlebotomine sand flies found to transmit Leishmania and other trypanosomatids to humans and other animals circulating in this area. This is the first study being reported on sand flies collected in an urban rainforest fragment in Amazonia.

  13. Acoustic signals in the sand fly Lutzomyia (Nyssomyia intermedia (Diptera: Psychodidae

    Directory of Open Access Journals (Sweden)

    Peixoto Alexandre A

    2011-05-01

    Full Text Available Abstract Background Acoustic signals are part of the courtship of many insects and they often act as species-specific signals that are important in the reproductive isolation of closely related species. Here we report the courtship songs of the sand fly Lutzomyia (Nyssomyia intermedia, one of the main vectors of cutaneous leishmaniasis in Brazil. Findings Recordings were performed using insects from three localities from Eastern Brazil: Posse and Jacarepaguá in Rio de Janeiro State and Corte de Pedra in Bahia State. The three areas have remnants of the Brazilian Atlantic forest, they are endemic for cutaneous leishmaniasis and L. intermedia is the predominant sand fly species. We observed that during courtship L. intermedia males from all populations produced pulse songs consisting of short trains. No significant differences in song parameters were observed between the males of the three localities. Conclusions L. intermedia males produce acoustic signals as reported for some other sand flies such as the sibling species of the Lutzomyia longipalpis complex. The lack of differences between the males from the three localities is consistent with previous molecular studies of the period gene carried out in the same populations, reinforcing the idea that L. intermedia is not a species complex in the studied areas and that the three populations are likely to have similar vectorial capacities.

  14. Changes of Sand Fly Populations and Leishmania infantum Infection Rates in an Irrigated Village Located in Arid Central Tunisia.

    Science.gov (United States)

    Barhoumi, Walid; Fares, Wasfi; Cherni, Saifedine; Derbali, Mohamed; Dachraoui, Khalil; Chelbi, Ifhem; Ramalho-Ortigao, Marcelo; Beier, John C; Zhioua, Elyes

    2016-03-16

    The current spread of zoonotic visceral leishmaniasis (ZVL) throughout arid areas of Central Tunisia is a major public health concern. The main objective of this study is to investigate whether the development of irrigation in arid bio-geographical areas in Central Tunisia have led to the establishment of a stable cycle involving sand flies of the subgenus Larroussius and Leishmania infantum, and subsequently to the emergence of ZVL. Sand flies were collected from the village of Saddaguia, a highly irrigated zone located within an arid bio-geographical area of Central Tunisia by using modified Centers for Diseases Control (CDC) light traps. Morphological keys were used to identify sand flies. Collected sand flies were pooled with up to 30 specimens per pool according to date and tested by nested Polymerase Chain Reaction (PCR) DNA sequencing from positive pools was used to identify Leishmania spp. A total of 4915 sand flies (2422 females and 2493 males) were collected from Saddaguia in September and in October 2014. Morphological identification confirmed sand flies of the subgenus Larroussius to be predominant. PCR analysis followed by DNA sequencing indicated that 15 pools were infected with L. infantum yielding an overall infection rate of 0.6%. The majority of the infected pools were of sand fly species belonging to subgenus Larroussius. Intense irrigation applied to the arid bio-geographical areas in Central Tunisia is at the origin of the development of an environment capable of sustaining important populations of sand flies of the subgenus Larroussius. This has led to the establishment of stable transmission cycles of L. infantum and subsequently to the emergence of ZVL.

  15. Man-biting sand fly species and the natural infetion with Leishmania promastigote in leishmaniasis-endemic areas of Ecuador.

    OpenAIRE

    Hashiguchi, Yoshihisa

    2014-01-01

    A countrywide surveillance of sand flies was performed to obtain information on their geographical distribution and natural infection by Leishmania protozoa in Ecuador. A total of 18,119 sand flies were collected by human landing collections during 32 years from 1982 to 2014, and 29 species were recognized. The most prevalent 10 species were Lutzomyia gomezi, Lu. robusta, Lu. hartmanni, Lu. shannoni, Lu. trapidoi, Lu. panamensis, Lu. maranonensis, Lu. ayacuchensis, Lu. tortura and Lu. yuilli ...

  16. Acetylcholinesterase of the sand fly, Phlebotomus papatasi (Scopoli): cDNA sequence, baculovirus expression, and biochemical properties

    OpenAIRE

    Temeyer, Kevin B; Brake, Danett K; Tuckow, Alexander P; Li, Andrew Y.; Pérez deLeón, Adalberto A

    2013-01-01

    Background Millions of people and domestic animals around the world are affected by leishmaniasis, a disease caused by various species of flagellated protozoans in the genus Leishmania that are transmitted by several sand fly species. Insecticides are widely used for sand fly population control to try to reduce or interrupt Leishmania transmission. Zoonotic cutaneous leishmaniasis caused by L. major is vectored mainly by Phlebotomus papatasi (Scopoli) in Asia and Africa. Organophosphates comp...

  17. Relative attraction of the sand fly Phlebotomus papatasi to local flowering plants in the Dead Sea region.

    Science.gov (United States)

    Müller, Günter C; Revay, Edita E; Schlein, Yosef

    2011-03-01

    Sugar is the main source of energy for the daily activities of sand flies. Considering its importance, there is surprisingly little information on sugar meal specific sources and sand fly attraction to plants, particularly in the field. In this study, we first needed to develop an effective sand fly trap that would be suitable for mass screening of potentially attractive flowering plants. Next, we used this trap to screen a total of 56 different flowering plant species and five plant species soiled with different types of honeydew. The plant baited traps together caught 21,978 P. papatasi. Out of the 56 types of flowering plants which were tested, 13 were shown to bait significantly more female sand flies, and 11 baited more male sand flies than the control. Based on an attraction index, the top three attractive plants in this study were the flowering plants Ochradenus baccatus, Prosopis farcta, and Tamirix nilotica. We believe that plants and phyto-chemicals have untapped potentials to attract sand flies. These could be used for control and, in combination with simple glue traps, as an alternative for existing monitoring systems.

  18. Oral treatment of rodents with fipronil for feed-through and systemic control of sand flies (Diptera: Psychodidae).

    Science.gov (United States)

    Mascari, T M; Stout, R W; Foil, L D

    2013-01-01

    The sand fly Phlebotomus papatasi Scopoli is the vector of Leishmania major (Yakimoff & Schokhor), which is maintained in populations of burrowing rodents. The purpose of this study was to conduct a laboratory study to determine the efficacy of oral treatment of rodents with fipronil for control of sand flies that feed on rodent feces as larvae or on rodent blood as adults. We determined through larval bioassays that fipronil was eliminated in feces of orally-treated hamsters at a level that was significantly toxic to sand fly larvae for 21 d after the hamsters had been withdrawn from a fipronil-treated diet. Through bloodfeeding bioassays, we also found that fipronil was present in the peripheral blood of hamsters at a concentration that was significantly toxic to bloodfeeding adult female sand flies for 49 d after the hamsters had been withdrawn from their treated diet. The results of this study suggest that fipronil acts as well as or better than feed-through or systemic insecticides that previously have been measured against sand flies, and is particularly promising because this single compound acts against both larvae and bloodfeeding adults. An area-wide approach using rodent baits containing a fipronil could suppress vector populations that originate in the vicinity of rodent reservoirs, and could be used to eliminate the most epidemiologically important part of the vector population: female sand flies that take bloodmeals on rodent reservoirs.

  19. Current knowledge of sand fly fauna (Diptera: Psychodidae) of northwestern Yemen and how it relates to leishmaniasis transmission.

    Science.gov (United States)

    El Sawaf, Bahira M; Kassem, Hala A; Mogalli, Nabil M; El Hossary, Shabaan S; Ramadan, Nadia F

    2016-10-01

    This report presents the results of the first entomological survey of the sand fly fauna in northwestern Yemen. Sand flies were collected using sticky paper traps and CDC light traps from Hajjah governorate, a cutaneous leishmaniasis focus due to Leishmania tropica. Six Phlebotomus species: P. alexandri, P. arabicus. P. bergeroti, P. orientalis, P. papatasi, P. sergenti and ten Sergentomyia species: S. africana, S. antennata, S. christophersi, S. dolichopa, S. dreyfussi, S. fallax, S. multidens, S. taizi, S. tiberiadis, S. yusafi were identified. P. alexandri was the most predominant Phlebotomus species and P. papatasi was a scarce species. S. fallax was the principal Sergentomyia species and S. dolichopa was the least species encountered. The diversity of the sand fly fauna within and among three altitudinal ranges using Simpson index and Jaccard's diversity coefficient respectively were measured. High species diversity was found in all altitude ranges. There seemed to be more association between sand fly fauna in higher altitudes with fauna from moderate altitudes. Sand fly seasonal activity showed a mono-modal trend in the lowland and a confluent bimodal trend in the highlands. Leishmania DNA could not be detected from 150 Phlebotomus females using PCR-RFLP. A possible zoonotic cutaneous transmission cycle due to Leishmania tropica in northwestern Yemen would involve P. arabicus as the sand fly vector and the rock hyrax as the reservoir host. The vector competence for P. alexandri as a vector of visceral leishmaniasis in Hajjah governorate is discussed.

  20. Recombinant acetylcholinesterase 1 of the sand fly Phlebotomus papatasi (Scopoli): expression, biochemical properties, and insensitivity to organophosphate inhibition

    Science.gov (United States)

    Phlebotomine sand flies are small hematophagous vectors of human and zoonotic leishmaniases present throughout tropical and subtropical areas of the world. These flies present serious problems for military operations and resident populations in the Middle East and other areas where they are endemic....

  1. Expression and Biochemical Properties of a Recombinant Acetylcholinesterase 1 of the Sand Fly, Phlebotomus papatasi (Scopoli) Insensitive to Organophosphate Inhibition

    Science.gov (United States)

    Phlebotomine sand flies are small hematophagous flies present throughout tropical and subtropical areas of the world and are vectors of human and zoonotic leishmaniases. Human cutaneous leishmaniasis is a debilitating disease presenting major problems for U.S. military operations in the Middle East,...

  2. Applied technique of the cemented fill with fly ash and fine-sands

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Traditional stabilization of backfilling material is done by using Portland cement. However, the high price of cement forced mining engineers to seek cheaper binding materials. Fly ash, which is the industrial waste from thermal power plant, possess the potential activity of jellification, and can be used in cemented fill as a partial substitute for cement to reduce the fill cost. Tests were done during the past few years in Xinqiao Pyrite Mine and Phoenix Copper Mine to determine the technology parameters and the suitable content of fly ash. Specimens with different cement/fly/ash tailings (sands) ratios were tested to obtain the strength values of the fill mass based on the analyses of both the chemical composition and physical and mechanical properties of fly ash. The compressive strength of specimens with a ratio of 1: 2: 8 (cement to fly ash to tailings)can reach 2 MPa after 90 d curing, totally meeting the requirement of artificial pillar and reducing the fill cost by 20%-30%.

  3. Dispersal pattern of the sand fly Lutzomyia neivai (Diptera: Psychodidae in a cutaneous leishmaniasis endemic rural area in Southeastern Brazil

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    Cláudio Casanova

    2005-11-01

    Full Text Available The dispersal pattern of the sand fly Lutzomyia neivai was studied through mark-release-recapture experiments in an American cutaneous leishmaniasis endemic rural area in Southeastern Brazil. Over 6500 specimens were marked with fluorescent powder and released in forest edge and peridomicile habitats from August to November 1999, February and April 2000. Recapture attempts were made using Shannon and CDC traps up to eight successive nights after releases. A total of 493 (7.58% specimens were recaptured. The number of recaptured males and females of L. neivai in CDC traps was not affected by the distance between the trap and the release points. Approximately 90% of males and females recaptured in CDC traps were caught up to 70 m from the release points. The maximum female flight range recorded was 128 m. The average flight range per day was less than 60 m for males and females. Of the flies released in forest edge, approximately 16% of the recaptured females were caught in Shannon traps in the peridomicile habitat. The results indicate that the movements of L. neivai are spatially focal and the possibility of dispersion from forest to peridomicile habitat may be an important way of contracting leishmaniasis in dwellings.

  4. Seasonal Dynamics of Phlebotomine Sand Fly Species Proven Vectors of Mediterranean Leishmaniasis Caused by Leishmania infantum

    Science.gov (United States)

    Alten, Bulent; Maia, Carla; Afonso, Maria Odete; Campino, Lenea; Jiménez, Maribel; González, Estela; Molina, Ricardo; Bañuls, Anne Laure; Prudhomme, Jorian; Vergnes, Baptiste; Toty, Celine; Cassan, Cécile; Rahola, Nil; Thierry, Magali; Sereno, Denis; Bongiorno, Gioia; Bianchi, Riccardo; Khoury, Cristina; Tsirigotakis, Nikolaos; Dokianakis, Emmanouil; Antoniou, Maria; Christodoulou, Vasiliki; Mazeris, Apostolos; Karakus, Mehmet; Ozbel, Yusuf; Arserim, Suha K.; Erisoz Kasap, Ozge; Gunay, Filiz; Oguz, Gizem; Kaynas, Sinan; Tsertsvadze, Nikoloz; Tskhvaradze, Lamzira; Gramiccia, Marina; Volf, Petr; Gradoni, Luigi

    2016-01-01

    Background The recent geographical expansion of phlebotomine vectors of Leishmania infantum in the Mediterranean subregion has been attributed to ongoing climate changes. At these latitudes, the activity of sand flies is typically seasonal; because seasonal phenomena are also sensitive to general variations in climate, current phenological data sets can provide a baseline for continuing investigations on sand fly population dynamics that may impact on future scenarios of leishmaniasis transmission. With this aim, in 2011–2013 a consortium of partners from eight Mediterranean countries carried out entomological investigations in sites where L. infantum transmission was recently reported. Methods/Principal Findings A common protocol for sand fly collection included monthly captures by CDC light traps, complemented by sticky traps in most of the sites. Collections were replicated for more than one season in order to reduce the effects of local weather events. In each site, the trapping effort was left unchanged throughout the survey to legitimate inter-seasonal comparisons. Data from 99,000 collected specimens were analyzed, resulting in the description of seasonal dynamics of 56,000 sand flies belonging to L. infantum vector species throughout a wide geographical area, namely P. perniciosus (Portugal, Spain and Italy), P. ariasi (France), P. neglectus (Greece), P. tobbi (Cyprus and Turkey), P. balcanicus and P. kandelakii (Georgia). Time of sand fly appearance/disappearance in collections differed between sites, and seasonal densities showed variations in each site. Significant correlations were found between latitude/mean annual temperature of sites and i) the first month of sand fly appearance, that ranged from early April to the first half of June; ii) the type of density trend, varying from a single peak in July/August to multiple peaks increasing in magnitude from May through September. A 3-modal trend, recorded for P. tobbi in Cyprus, represents a novel

  5. Seasonal Dynamics of Phlebotomine Sand Fly Species Proven Vectors of Mediterranean Leishmaniasis Caused by Leishmania infantum.

    Directory of Open Access Journals (Sweden)

    Bulent Alten

    2016-02-01

    Full Text Available The recent geographical expansion of phlebotomine vectors of Leishmania infantum in the Mediterranean subregion has been attributed to ongoing climate changes. At these latitudes, the activity of sand flies is typically seasonal; because seasonal phenomena are also sensitive to general variations in climate, current phenological data sets can provide a baseline for continuing investigations on sand fly population dynamics that may impact on future scenarios of leishmaniasis transmission. With this aim, in 2011-2013 a consortium of partners from eight Mediterranean countries carried out entomological investigations in sites where L. infantum transmission was recently reported.A common protocol for sand fly collection included monthly captures by CDC light traps, complemented by sticky traps in most of the sites. Collections were replicated for more than one season in order to reduce the effects of local weather events. In each site, the trapping effort was left unchanged throughout the survey to legitimate inter-seasonal comparisons. Data from 99,000 collected specimens were analyzed, resulting in the description of seasonal dynamics of 56,000 sand flies belonging to L. infantum vector species throughout a wide geographical area, namely P. perniciosus (Portugal, Spain and Italy, P. ariasi (France, P. neglectus (Greece, P. tobbi (Cyprus and Turkey, P. balcanicus and P. kandelakii (Georgia. Time of sand fly appearance/disappearance in collections differed between sites, and seasonal densities showed variations in each site. Significant correlations were found between latitude/mean annual temperature of sites and i the first month of sand fly appearance, that ranged from early April to the first half of June; ii the type of density trend, varying from a single peak in July/August to multiple peaks increasing in magnitude from May through September. A 3-modal trend, recorded for P. tobbi in Cyprus, represents a novel finding for a L. infantum vector

  6. Multilocus molecular and phylogenetic analysis of phlebotomine sand flies (Diptera: Psychodidae) from southern Italy.

    Science.gov (United States)

    Latrofa, Maria Stefania; Dantas-Torres, Filipe; Weigl, Stefania; Tarallo, Viviana Domenica; Parisi, Antonio; Traversa, Donato; Otranto, Domenico

    2011-08-01

    This study reports a combined analysis of mitochondrial and ribosomal DNA target regions of phlebotomine sand flies (Diptera: Psychodidae) from the Mediterranean region. A ∼900 bp long fragment of the mitochondrial DNA encompassing regions within cytb and nd1 gene and the complete ITS2 ribosomal region (∼500 bp) were sequenced and characterized for Phlebotomus perniciosus, Phlebotomus perfiliewi, Phlebotomus neglectus, Phlebotomus papatasi, and Sergentomyia minuta, captured in two sites of southern Italy. From one to eight mitochondrial haplotypes and from one to three ITS2 sequence types were found for the examined specimens according to the different sand fly species. The mean interspecific difference in the mitochondrial sequences was of 16.1%, with an overall intraspecific nucleotide variation from 0.1 to 2.8%. A higher interspecific difference (mean 25.1%) was recorded for the ITS2 sequence, with an overall intraspecific nucleotide variation up to 4.9%. The sequence types alignment of ITS2 region showed that all phlebotomine specimens possessed a split 5.8S rRNA, consisting of a mature 5.8S rRNA and a 2S rRNA separated by a short transcribed spacer. Phylogenetic analysis of the Phlebotomus spp. sequences, herein determined and of those available in GenBank™ were concordant in clustering P. neglectus, P. perfiliewi and P. papatasi with the same species collected from different geographic areas of the Mediterranean basin in four main clades for mtDNA and ITS2, respectively. This study demonstrates the utility of multilocus sequencing, provides a dataset for the molecular identification of the most prevalent phlebotomine sand flies in southern Europe and defines the phylogenetic relationships among species examined.

  7. Species structure of sand fly (Diptera: Psychodidae fauna in the Brazilian western Amazon

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    Luiz Herman Soares Gil

    2009-11-01

    Full Text Available We surveyed areas of the state of Rondônia in western Amazon for phlebotomine, which are potential vectors of leishmaniasis. A total of 5,998 specimens were captured, resulting in the identification of 48 species within the Lutzomyia (99.98% and Brumptomyia (0.02% genera. The predominant species was Lutzomyia davisi, followed by Lutzomyia umbratilis, Lutzomyia llanosmartinsi, Lutzomyia c. carrerai, Lutzomyia dendrophyla, Lutzomyia nevesi and Lutzomyia whitmani. All sand flies identified as vectors for cutaneous leishmaniasis in Brazil, i.e., Lu. davisi, Lu. umbratilis, Lu. c. carrerai and Lu. whitmani, were found in the surveyed areas.

  8. Evaluation of rhodamine B as an orally delivered biomarker for rodents and a feed-through transtadial biomarker for phlebotomine sand flies (Diptera: Psychodidae).

    Science.gov (United States)

    Mascari, T M; Foil, L D

    2009-09-01

    The purpose of this study was to evaluate the use of rhodamine B as an orally delivered biomarker for rodents and a feed-through transtadial biomarker for phlebotomine sand flies (Diptera: Psychodidae). Rhodamine B-treated hamsters were visibly marked for up to 8 wk, and their feces were fluorescent when examined under a fluorescence microscope. The development and survival of sand fly larvae fed feces of rhodamine B-treated hamsters were not significantly different from control sand flies. Adult male and female sand flies, that had been fed as larvae the feces of rhodamine B-treated hamsters, were fluorescent when examined using fluorescent microscopy and could be distinguished from control sand flies. Adult female sand flies that took bloodmeals from rhodamine B-treated hamsters were fluorescent when examined immediately after feeding. Rhodamine B incorporated rodent baits could be used to detect adult male and female sand flies that fed on the feces of baited rodents as larvae, or adult female sand flies that have taken a bloodmeal from bait-fed rodents. This would allow the delineation of specific foci with rodent-sand fly associations that would be susceptible to control by using feed-through or systemic insecticides.

  9. Laboratory evaluation of oral treatment of rodents with systemic insecticides for control of bloodfeeding sand flies (Diptera: Psychodidae).

    Science.gov (United States)

    Mascari, Thomas Michael; Stout, Rhett W; Foil, Lane D

    2012-08-01

    The purpose of this study was to evaluate the efficacy of oral treatment of rodents with diets containing the systemic insecticides ivermectin, abamectin, imidacloprid, or spinosad, to control bloodfeeding sand flies. We found that diets containing concentrations higher than 10 mg/kg abamectin were not palatable to rodents, and that a diet containing 10 mg/kg abamectin (a palatable concentration) did not cause 100% mortality of bloodfeeding sand flies. Treatment of rodents with imidacloprid was effective for less than 3 days post-treatment. Treatment of rodents with diets containing 20 mg/kg ivermectin or 5000 mg/kg spinosad caused 100% mortality of bloodfeeding sand flies for at least 1 week. The efficacy of ivermectin and spinosad also were not reduced when combined with the fluorescent tracer dye rhodamine B in a single diet. We also did not observe significant benefits by increasing the feeding period of the rodents from 3 to 6 or 9 days. We conclude that ivermectin and spinosad are effective as rodent systemic insecticides against bloodfeeding sand flies, and suggest that weekly treatment of wild rodent reservoirs of Leishmania major with bait containing one of these systemic insecticides could be a useful tool as part of a sand fly control program.

  10. Environmental factors underlying spatial patterns of sand flies (Diptera: Psychodidae) associated with leishmaniasis in southern Sinai, Egypt.

    Science.gov (United States)

    Kassem, Hala A; Siri, Jose; Kamal, Hany A; Wilson, Mark L

    2012-07-01

    Although Leishmania major is endemic in parts of the Sinai of Egypt, the ecology and distribution of Leishmania sand fly vectors in southern Sinai has not been well characterized. Accordingly, additional sand fly samples were obtained at 41 sites in the southern Sinai region during 1996-1997, and analyzed to improve the characterization of risk of sand fly-borne pathogens. Using a Geographic Information System (GIS), species-specific spatial distributions that might suggest zoonotic cutaneous leishmaniasis (ZCL) risk areas were determined in relation to contextual environmental factors, including geology, hydrogeology, climate variables and elevation. Southern Sinai was characterized by a diverse sand fly fauna (eight Phlebotomus species), probably attributable to highly variable landscape and environmental factors. Phlebotomus alexandri, Phlebotomus kazeruni and Phlebotomus sergenti were widespread and abundant, Phlebotomus papatasi and Phlebotomus bergeroti were less frequent, and Phlebotomus arabicus, Phlebotomus major and Phlebotomus orientalis had highly restricted distributions. Logistic regression models indicated that elevation and climatic conditions were limiting determinants for the distributions of sand flies in southern Sinai. Based on the predicted distribution of P. papatasi, a recognized vector of L. major, about one-quarter of southern Sinai may be at high risk of ZCL. Risk areas for the suspected ZCL vector P. bergeroti had a more patchy distribution. Results suggest that future studies should include other factors related to vector abundance, vector competence, human population, and parasite and reservoir host(s) to produce more comprehensive ZCL transmission risk maps, thus helping in planning effective prevention and control strategies.

  11. Exosome Secretion by the Parasitic Protozoan Leishmania within the Sand Fly Midgut

    Directory of Open Access Journals (Sweden)

    Vanessa Diniz Atayde

    2015-11-01

    Full Text Available Despite several studies describing the secretion of exosomes by Leishmania in vitro, observation of their formation and release in vivo has remained a major challenge. Herein, we show that Leishmania constitutively secretes exosomes within the lumen of the sand fly midgut through a mechanism homologous to the mammalian pathway. Through egestion experiments, we demonstrate that Leishmania exosomes are part of the sand fly inoculum and are co-egested with the parasite during the insect’s bite, possibly influencing the host infectious process. Indeed, co-inoculation of mice footpads with L. major plus midgut-isolated or in-vitro-isolated L. major exosomes resulted in a significant increase in footpad swelling. Notably, co-injections produced exacerbated lesions through overinduction of inflammatory cytokines, in particular IL-17a. Our data indicate that Leishmania exosomes are an integral part of the parasite’s infectious life cycle, and we propose to add these vesicles to the repertoire of virulence factors associated with vector-transmitted infections.

  12. SALO, a novel classical pathway complement inhibitor from saliva of the sand fly Lutzomyia longipalpis

    Science.gov (United States)

    Ferreira, Viviana P.; Fazito Vale, Vladimir; Pangburn, Michael K.; Abdeladhim, Maha; Ferreira Mendes-Sousa, Antonio; Coutinho-Abreu, Iliano V.; Rasouli, Manoochehr; Brandt, Elizabeth A.; Meneses, Claudio; Lima, Kolyvan Ferreira; Nascimento Araújo, Ricardo; Horácio Pereira, Marcos; Kotsyfakis, Michalis; Oliveira, Fabiano; Kamhawi, Shaden; Ribeiro, Jose M. C.; Gontijo, Nelder F.; Collin, Nicolas; Valenzuela, Jesus G.

    2016-01-01

    Blood-feeding insects inject potent salivary components including complement inhibitors into their host’s skin to acquire a blood meal. Sand fly saliva was shown to inhibit the classical pathway of complement; however, the molecular identity of the inhibitor remains unknown. Here, we identified SALO as the classical pathway complement inhibitor. SALO, an 11 kDa protein, has no homology to proteins of any other organism apart from New World sand flies. rSALO anti-complement activity has the same chromatographic properties as the Lu. longipalpis salivary gland homogenate (SGH)counterparts and anti-rSALO antibodies blocked the classical pathway complement activity of rSALO and SGH. Both rSALO and SGH inhibited C4b deposition and cleavage of C4. rSALO, however, did not inhibit the protease activity of C1s nor the enzymatic activity of factor Xa, uPA, thrombin, kallikrein, trypsin and plasmin. Importantly, rSALO did not inhibit the alternative or the lectin pathway of complement. In conclusion our data shows that SALO is a specific classical pathway complement inhibitor present in the saliva of Lu. longipalpis. Importantly, due to its small size and specificity, SALO may offer a therapeutic alternative for complement classical pathway-mediated pathogenic effects in human diseases. PMID:26758086

  13. Infection of sand flies collected from different bio-geographical areas of Tunisia with phleboviruses.

    Science.gov (United States)

    Fares, W; Charrel, R N; Dachraoui, K; Bichaud, L; Barhoumi, W; Derbali, M; Cherni, S; Chelbi, I; de Lamballerie, X; Zhioua, E

    2015-01-01

    An entomological investigation performed in 2013 covering different bio-geographical areas varying from humid in the north to the arid in the center showed that sand flies of the subgenus Larroussius including Phlebotomus perniciosus, Phlebotomus perfiliewi, and Phlebotomus longicuspis are abundant and widely distributed in Tunisia. A total of 3992 collected and pooled with up to 30 specimens per pool based on sex, trapping location and collection data were tested for the presence of phleboviruses by nested reverse transcriptase polymerase chain reaction and sequencing. Of a total of 135 pools, 23 were positive, yielding and minimum infection rate of 0.6%. Phylogenetic analysis performed using partial amino acid sequence in the polymerase gene showed that all these phleboviruses were grouped in one cluster clearly distinct from but closely related to Massilia virus and Granada virus. This putative novel virus, tentatively called Saddaguia virus (SADV), is widely distributed in Tunisia. Together with Toscana, Punique, and Utique viruses, SADV is the fourth recognized phlebovirus to be transmitted by sand flies in Tunisia. The medical and public health interest of SADV remains to be investigated.

  14. Phlebotominae sand flies associated with a tegumentary leishmaniasis outbreak, Tucumán Province, Argentina.

    Science.gov (United States)

    Salomón, Oscar Daniel; Quintana, María Gabriela; Flores, Isolina; Andina, Ana María; Molina, Silvia; Montivero, Lucía; Rosales, Isabel

    2006-01-01

    The distribution of sand flies and cases of tegumentary leishmaniasis in the area surrounding JB Alberd city, and the proximities of Catamarca province were studied, after an increase of reported cases from JB Alberdi, Tucumán province, in 2003. Of 14 confirmed cases, 57% were females and 57% were less than 15 years old, suggesting peridomestic transmission. However, 86% of them lived close to the Marapa river forest gallery and related wooded areas. Over 1,013 sand flies were collected; Lutzomyia neivai (Pinto, 1926) was prevalent at all the sites (92.3%), while Lutzomyia migonei (França, 1920) (6.7%) and Lu. cortelezzii (Brèthes, 1923) (1%) were also found. The spatial distribution of Lu. neivai overlapped that of the cases, with higher abundance in microfocal hot spots close to the river in stable vegetated habitats or modified habitats with shadow and animal blood sources. The cumulative outcome of anthropic, ecological and climatic factors could have contributed to the onset of the outbreak.

  15. First Human Cases of Leishmania (Viannia) lainsoni Infection and a Search for the Vector Sand Flies in Ecuador.

    Science.gov (United States)

    Kato, Hirotomo; Bone, Abdon E; Mimori, Tatsuyuki; Hashiguchi, Kazue; Shiguango, Gonzalo F; Gonzales, Silvio V; Velez, Lenin N; Guevara, Angel G; Gomez, Eduardo A; Hashiguchi, Yoshihisa

    2016-05-01

    An epidemiological study of leishmaniasis was performed in Amazonian areas of Ecuador since little information on the prevalent Leishmania and sand fly species responsible for the transmission is available. Of 33 clinical specimens from patients with cutaneous leishmaniasis (CL), causative parasites were identified in 25 samples based on cytochrome b gene analysis. As reported previously, Leishmania (Viannia) guyanensis and L. (V.) braziliensis were among the causative agents identified. In addition, L. (V.) lainsoni, for which infection is reported in Brazil, Bolivia, Peru, Suriname, and French Guiana, was identified in patients with CL from geographically separate areas in the Ecuadorian Amazon, corroborating the notion that L. (V.) lainsoni is widely distributed in South America. Sand flies were surveyed around the area where a patient with L. (V.) lainsoni was suspected to have been infected. However, natural infection of sand flies by L. (V.) lainsoni was not detected. Further extensive vector searches are necessary to define the transmission cycle of L. (V.) lainsoni in Ecuador.

  16. Diversity of sand flies (Diptera, Psychodidae) in southwest Iran with emphasis on synanthropy of Phlebotomus papatasi and Phlebotomus alexandri.

    Science.gov (United States)

    Jahanifard, Elham; Yaghoobi-Ershadi, Mohammad Reza; Akhavan, Amir Ahmad; Akbarzadeh, Kamran; Hanafi-Bojd, Ahmad Ali; Rassi, Yavar; Sedaghat, Mohammad Mehdi; Shirzadi, Mohammad Reza; Karimi, Ameneh

    2014-12-01

    Zoonotic Cutaneous Leishmaniasis (ZCL) is still a serious health problem in Iran. The objective of the study was to determine the differences in sand fly biodiversity in Shush (plain) and Khorramshahr (littoral) Counties, Khuzestan Province, southwest Iran. Sand flies were collected using sticky paper traps from urban, semi urban, agricultural and natural ecotypes. Alpha and beta diversity were calculated using Shannon-Weiner index and Jaccard's and Sorensen's coefficients, respectively. Synanthropic index was determined for the first time for Phlebotomus papatasi and Phlebotomus alexandri in different land use categories in Iran. Totally 11213 specimens, 68.47% in Shush and 31.53% in Khorramshahr, were collected. Eleven species of sand flies including, 2 of genus Phlebotomus and 9 of genus Sergentomyia were identified. Sergentomyia christophersi was found as a new record. Dominant species were P. papatasi and Sergentomyia sintoni. Shannon-Weiner index, richness and evenness in semi urban area of Shush County were more than other habitats. The analysis of α biodiversity showed that agricultural ecosystem of Khorramshahr County had the highest diversity due to maximal richness and diversity and also relatively high evenness. Comparison of similarity of the sand flies population composition between Shush and Khorramshahr indicated the maximum similarity between the urban area of Shush and the semi urban area of Khorramshahr (Sj=75% and Ss=86%). Synanthropic index of P. papatasi and P. alexandri were calculated to be -83.34 and -91.18, respectively in Shush County. Estimated synanthropic indices for P. papatasi and P. alexandri in three habitats (natural, semi urban and urban) of Khorramshahr County were -69.84 and -85.89, in the same order. The factors for having high diversity of sand flies in the plain area studied may be due to higher annual precipitation, the related land use and land cover. The changes on the composition of sand flies are perhaps due to human

  17. Entomological study of sand flies (Diptera:Psychodidae:Phlebotominae) in Asalouyeh, the heartland of an Iranian petrochemical industry

    Institute of Scientific and Technical Information of China (English)

    Hamzeh Alipour; Hossien Darabi; Tahere Dabbaghmanesh; Mehdi Bonyani

    2014-01-01

    Objective: To investigate the fauna and seasonal activity of different species of sand flies (Diptera:Psychodidae: Phlebotominae) in Asalouyeh, the heartland of an Iranian petrochemical industry, Southern Iran, as a oil rich district. Sand flies are the vectors of at least three different kinds of disease, the most important of which is leishmaniasis, and it is a major public health problem in Iran with increased annual occurrence of clinical episodes.Methods:cleared in puris medium and identified morphologically, twice a month from April to March 2008.Results:A total of 3 497 sand flies of rural regions were collected by sticky traps fixed, and Sinton, 1928, Phlebotomus papatasi Scopoli, 1910, Phlebotomus bergeroti Parrot and Phlebotomus sergenti Parrot) and one of genus Sergentomyia (Sergentomyia tiberiadis Alder, Theodor & Lourie, 1930). The most prevalent species was Phlebotomus papatasi, presented 56.4% of the identified flies. The others were Phlebotomus sergenti (22.5%), Phlebotomus alexandri (4.5%), Phlebotomusbergeroti Predominant species included four of genus Phlebotomus (Phlebotomus alexandri than that of males (32%). The abundance of sand flies represented two peaks of activity; one in early May and the other one in the first half of September in the region. (12%) and Sergentomyia tiberiadis (5%) as well. The percentage of females (68%) was more Conclusion: Phlebotomus papatasi is the probable vector of zoonotic cutaneous leishmaniasis in the region. Further molecular studies are needed to determine the definite vector of the region.

  18. Evaluation of insecticides and repellents for the control of the sand fly Phlebotomus papatasi to protect deployed U.S. Military personnel

    Science.gov (United States)

    Phlebotomine sand flies, including Phlebotomus papatasi, are important blood feeders and vectors that transmit the disease agents (Leishmania) that cause Leishmaniasis. Deployed U.S. Military Personnel in Iraq and Afghanistan suffered from sand fly bites and the disease they transmit. A USDA-DoD joi...

  19. Ground ULV and thermal fog applications against Phlebotomine sand fly vectors of Leishmania in a hot arid environment in western Kenya

    Science.gov (United States)

    Phlebotomine sand fly vectors of Leishmania continue to threaten US military operations in Africa, Southwest Asia, and the Middle East. Ultra-low volume (ULV) and/or thermal fog pesticide dispersal are potentially effective against sand flies, but operational guidance is thinly based on mosquito con...

  20. Description of a new phlebotomine species (Diptera: Psychodidae, Phlebotominae) and new records of sand flies from the State of Acre, northern Brazil.

    Science.gov (United States)

    Teles, Carolina Bioni Garcia; Freitas, Rui Alves; De Oliveira, Arley Faria José; Ogawa, Guilherme Maerschner; De Araújo, Edicarlos André Cavalcante; Medeiros, Jansen Fernandes; Pessoa, Felipe Arley Costa; Camargo, Luís Marcelo Aranha

    2013-01-25

    Groundbreaking studies of phlebotomine sand fly populations in Assis Brasil, State of Acre, Brazil, resulted in the collection of 13 new records of phlebotomine sand flies and one previously undescribed species. Lutzomyia naiffi sp. nov. is described here. The new species is similar to Lutzomyia columbiana (Ristorcelli & Van Ty) in measurements and other morphological characters.

  1. Direct Multiplex PCR (dmPCR) for the Identification of Six Phlebotomine Sand Fly Species (Diptera: Psychodidae), Including Major Leishmania Vectors of the Mediterranean

    Science.gov (United States)

    Sand flies (Diptera: Psychodidae, subfamily Phlebotominae) are haematophagous insects that are known to transmit several anthroponotic and zoonotic diseases. Reliable identification of sand flies at species level is crucial for their surveillance, the detection and spread of their pathogens and the ...

  2. Phlebotomine Sand Fly Fauna and Leishmania Infection in the Vicinity of the Serra do Cipó National Park, a Natural Brazilian Heritage Site

    Directory of Open Access Journals (Sweden)

    Rosana Silva Lana

    2015-01-01

    Full Text Available In the New World, the leishmaniases are primarily transmitted to humans through the bites of Leishmania-infected Lutzomyia (Diptera: Psychodidae phlebotomine sand flies. Any or both of two basic clinical forms of these diseases are endemic to several cities in Brazil—the American cutaneous leishmaniasis (ACL and the American visceral leishmaniasis (AVL. The present study was conducted in the urban area of a small-sized Brazilian municipality (Jaboticatubas, in which three cases of AVL and nine of ACL have been reported in the last five years. Jaboticatubas is an important tourism hub, as it includes a major part of the Serra do Cipó National Park. Currently, no local data is available on the entomological fauna or circulating Leishmania. During the one-year period of this study, we captured 3,104 phlebotomine sand flies belonging to sixteen Lutzomyia species. In addition to identifying incriminated or suspected vectors of ACL with DNA of the etiological agent of AVL and vice versa, we also detected Leishmania DNA in unexpected Lutzomyia species. The expressive presence of vectors and natural Leishmania infection indicates favorable conditions for the spreading of leishmaniases in the vicinity of the Serra do Cipó National Park.

  3. Phlebotomine sand fly fauna and leishmania infection in the vicinity of the Serra do Cipó National Park, a natural Brazilian heritage site.

    Science.gov (United States)

    Lana, Rosana Silva; Michalsky, Érika Monteiro; Fortes-Dias, Consuelo Latorre; França-Silva, João Carlos; Lara-Silva, Fabiana de Oliveira; Lima, Ana Cristina Vianna Mariano da Rocha; Moreira de Avelar, Daniel; Martins, Juliana Cristina Dias; Dias, Edelberto Santos

    2015-01-01

    In the New World, the leishmaniases are primarily transmitted to humans through the bites of Leishmania-infected Lutzomyia (Diptera: Psychodidae) phlebotomine sand flies. Any or both of two basic clinical forms of these diseases are endemic to several cities in Brazil--the American cutaneous leishmaniasis (ACL) and the American visceral leishmaniasis (AVL). The present study was conducted in the urban area of a small-sized Brazilian municipality (Jaboticatubas), in which three cases of AVL and nine of ACL have been reported in the last five years. Jaboticatubas is an important tourism hub, as it includes a major part of the Serra do Cipó National Park. Currently, no local data is available on the entomological fauna or circulating Leishmania. During the one-year period of this study, we captured 3,104 phlebotomine sand flies belonging to sixteen Lutzomyia species. In addition to identifying incriminated or suspected vectors of ACL with DNA of the etiological agent of AVL and vice versa, we also detected Leishmania DNA in unexpected Lutzomyia species. The expressive presence of vectors and natural Leishmania infection indicates favorable conditions for the spreading of leishmaniases in the vicinity of the Serra do Cipó National Park.

  4. Flagellate infections of Brazilian sand flies (Diptera: Psychodidae): isolation in vitro and biochemical identification of Endotrypanum and Leishmania.

    Science.gov (United States)

    Arias, J R; Miles, M A; Naiff, R D; Povoa, M M; de Freitas, R A; Biancardi, C B; Castellon, E G

    1985-11-01

    Flagellate infections were found in 1,063 of 18,895 sand flies collected in the states of Amazonas, Pará, Rondonia and Acre, Brazil. Infection rates were 13.4% (species group Shannoni); 7.5% (subgenus Nyssomyia); 6.7% (subgenus Lutzomyia series Cruciata); 0.5% (genus Psychodopygus) and 3.1% for other sand flies (various subgenera). Leishmania braziliensis guyanensis and L. mexicana amazonensis were isolated, respectively, from the known vectors, Lutzomyia umbratilis and L. flaviscutellata. Single stocks of L. braziliensis-like and L. mexicana-like organisms were isolated, respectively, from L. whitmani and L. yuilli. Thirty-eight flagellate stocks, isolated by direct culture from sand flies were characterized in detail by morphology in culture, behavior in hamsters and mice and by enzyme profiles. Sixteen stocks from Lutzomyia sp. (Shannoni group) were identified as Endotrypanum schaudinni; 8 stocks from Lutzomyia sp. (Shannoni group) were identified as Endotrypanum sp.; 7 stocks from Psychodopygus ayrozai and P. paraensis were identified as Leishmania sp. previously isolated from the armadillo, Dasypus novemcinctus; 2 stocks of Trypanosoma rangeli were isolated from recently fed Lutzomyia sp. (Shannoni group) sand flies; the remaining 5 stocks from L. umbratilis and L. yuilli could not be identified. Observations suggested that Shannoni group sand flies were the natural vectors of Endotrypanum. Leishmania sp. infections in the man-biting flies P. ayrozai and P. paraensis were restricted to the midgut and associated with recent bloodmeals. Unidentified flagellates in L. umbratilis and L. yuilli were distributed throughout the digestive tract with no trace of bloodmeals.

  5. Leishmania major survival in selective Phlebotomus papatasi sand fly vector requires a specific SCG-encoded lipophosphoglycan galactosylation pattern.

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    Deborah E Dobson

    Full Text Available Phlebotomine sand flies that transmit the protozoan parasite Leishmania differ greatly in their ability to support different parasite species or strains in the laboratory: while some show considerable selectivity, others are more permissive. In "selective" sand flies, Leishmania binding and survival in the fly midgut typically depends upon the abundant promastigote surface adhesin lipophosphoglycan (LPG, which exhibits species- and strain-specific modifications of the dominant phosphoglycan (PG repeat units. For the "selective" fly Phlebotomus papatasi PpapJ, side chain galactosyl-modifications (scGal of PG repeats play key roles in parasite binding. We probed the specificity and properties of this scGal-LPG PAMP (Pathogen Associated Molecular Pattern through studies of natural isolates exhibiting a wide range of galactosylation patterns, and of a panel of isogenic L. major engineered to express similar scGal-LPG diversity by transfection of SCG-encoded β1,3-galactosyltransferases with different activities. Surprisingly, both 'poly-scGal' and 'null-scGal' lines survived poorly relative to PpapJ-sympatric L. major FV1 and other 'mono-scGal' lines. However, survival of all lines was equivalent in P. duboscqi, which naturally transmit L. major strains bearing 'null-scGal'-LPG PAMPs. We then asked whether scGal-LPG-mediated interactions were sufficient for PpapJ midgut survival by engineering Leishmania donovani, which normally express unsubstituted LPG, to express a 'PpapJ-optimal' scGal-LPG PAMP. Unexpectedly, these "L. major FV1-cloaked" L. donovani-SCG lines remained unable to survive within PpapJ flies. These studies establish that midgut survival of L. major in PpapJ flies is exquisitely sensitive to the scGal-LPG PAMP, requiring a specific 'mono-scGal' pattern. However, failure of 'mono-scGal' L. donovani-SCG lines to survive in selective PpapJ flies suggests a requirement for an additional, as yet unidentified L. major-specific parasite

  6. Ecology of sand flies in a low-density residential rural area, with mixed forest/agricultural exploitation, in north-eastern Brazil.

    Science.gov (United States)

    Miranda, Débora Elienai de Oliveira; Sales, Kamila Gaudêncio da Silva; Faustino, Maria Aparecida da Gloria; Alves, Leucio Câmara; Brandão-Filho, Sinval Pinto; Dantas-Torres, Filipe; de Carvalho, Gílcia Aparecida

    2015-06-01

    Cutaneous leishmaniasis caused by Leishmania braziliensis is endemic in Brazil, where Lutzomyia whitmani is the most important vector involved in the transmission to humans, particularly in the peridomestic environment. Herein, we assessed the ecology of sand flies, including Lu. whitmani, in a low-density residential rural area with mixed forest/agricultural exploitation in north-eastern Brazil, where cutaneous leishmaniasis is endemic. Particularly, we hypothesized that sand fly abundance was correlated with climatic variables. Sand fly collections were carried out monthly from August 2013 to August 2014, using seven CDC light traps, for three consecutive nights, in three kinds of environments: indoor, peridomicile and forest. Collected sand flies were identified based on morphology and females of Lu. whitmani (n=169), Lu. amazonensis (n=134) and Lu. complexa (n=21) were selected and tested by PCR for Leishmania (Viannia) spp. In total, 5167 sand flies belonging to 19 species were identified, being that Lu. choti (43.2%) was the most frequent species, followed by Lu. amazonensis (16.6%), Lu. whitmani (15.8%), Lu. sordellii (10.7%) and Lu. quinquefer (5.8%), which together represented over 90% of the collected sand flies. All females tested by PCR were negative. The number of sand flies collected daily was positively correlated with temperature and negatively correlated with rainfall and relative humidity. Furthermore, there was a positive correlation between daily number of sand flies and daily average saturation deficit. This study points out that the number of sand flies captured daily is correlated to climatic variables, including saturation deficit, which may represent a useful parameter for monitoring sand fly populations in leishmaniasis-endemic areas.

  7. Lutzomyia (Trichophoromyia pastazaensis, a new species of phlebotomine sand fly (Diptera: Psychodidae: Phlebotominae from the Peruvian Amazon

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    R. Fernandez

    1993-12-01

    Full Text Available The phlebotomine sand fly Lutzomyia pastazaensis n. sp. is described and illustrated from specimens collected from the edge of primary forest near Andoas, Department of Loreto, Peru (03º00'S, 76º05'W. This species appears to belong to the subgenus Trichophoromyia Barreto 1962, whose members are generally restricted to the Amazon Basin.

  8. Lutzomyia (Trichophoromyia) pastazaensis, a new species of phlebotomine sand fly (Diptera: Psychodidae: Phlebotominae) from the Peruvian Amazon

    OpenAIRE

    R. Fernandez; Carbajal,F.; Alexander, B; J. T. Need

    1993-01-01

    The phlebotomine sand fly Lutzomyia pastazaensis n. sp. is described and illustrated from specimens collected from the edge of primary forest near Andoas, Department of Loreto, Peru (03º00'S, 76º05'W). This species appears to belong to the subgenus Trichophoromyia Barreto 1962, whose members are generally restricted to the Amazon Basin.

  9. Survey of sand flies (Diptera: Psychodidae) in an environmentally protected area in Brazil.

    Science.gov (United States)

    Saraiva, Lara; Silva Reis, Alanna; Marteleto Nunes Rugani, Jeronimo; Sampaio Pereira, Agnes Antônia; Rêgo, Felipe Dutra; Vianna Mariano da Rocha Lima, Ana Cristina; Gontijo, Célia Maria Ferreira; Andrade Filho, José Dilermando

    2015-01-01

    Brazil is one of the most important endemic areas for leishmaniasis worldwide. Protected areas that are tourist attractions likely present an important risk of transmission of cutaneous leishmaniasis (CL). Furthermore, with the geographical expansion of visceral leishmaniasis (VL), several studies have recorded the occurrence of its vector, Lutzomyia longipalpis, and cases of human and canine VL in such tourist areas. The Parque Estadual do Sumidouro is an environmentally protected area located in the Brazilian Cerrado biome and in an important area endemic for leishmaniasis in the state of Minas Gerais. The purpose of this study was to monitor the sand fly fauna in areas of tourist activity in the park. Sampling was performed every month, from September 2011 to August 2013, using CDC light traps at six sites of differing environmental characteristics. Sampled specimens were identified following Galati (2003), and females were submitted to molecular techniques for the detection and identification of Leishmania DNA. A total of 4,675 sand fly specimens of 25 species belonging to nine genera were collected. The most abundant species were Micropygomyia quinquefer, Lutzomyia renei and Pintomyia pessoai, although only Pi. pessoai is implicated in the transmission of Leishmania braziliensis. The species accumulation curve reached saturation on the 16th sampling event. Species richness, diversity and evenness differed among the sampled areas. The seasonal curve was not determined by a single unique species, and no single species was the most abundant in all environments sampled. The main vector of Leishmania (Leishmania) infantum, Lutzomyia longipalpis, accounted for only 5.35% of the specimens collected. Proven or suspected vectors of Leishmania (Viannia) braziliensis were recorded, and one female of the cortellezzii complex tested positive for Le. braziliensis DNA. Even with a low infection rate (0.62%), these data indicate the circulation of the parasite and reinforce

  10. Survey of Sand Flies (Diptera: Psychodidae) in an Environmentally Protected Area in Brazil

    Science.gov (United States)

    Silva Reis, Alanna; Marteleto Nunes Rugani, Jeronimo; Sampaio Pereira, Agnes Antônia; Rêgo, Felipe Dutra; Vianna Mariano da Rocha Lima, Ana Cristina

    2015-01-01

    Brazil is one of the most important endemic areas for leishmaniasis worldwide. Protected areas that are tourist attractions likely present an important risk of transmission of cutaneous leishmaniasis (CL). Furthermore, with the geographical expansion of visceral leishmaniasis (VL), several studies have recorded the occurrence of its vector, Lutzomyia longipalpis, and cases of human and canine VL in such tourist areas. The Parque Estadual do Sumidouro is an environmentally protected area located in the Brazilian Cerrado biome and in an important area endemic for leishmaniasis in the state of Minas Gerais. The purpose of this study was to monitor the sand fly fauna in areas of tourist activity in the park. Sampling was performed every month, from September 2011 to August 2013, using CDC light traps at six sites of differing environmental characteristics. Sampled specimens were identified following Galati (2003), and females were submitted to molecular techniques for the detection and identification of Leishmania DNA. A total of 4,675 sand fly specimens of 25 species belonging to nine genera were collected. The most abundant species were Micropygomyia quinquefer, Lutzomyia renei and Pintomyia pessoai, although only Pi. pessoai is implicated in the transmission of Leishmania braziliensis. The species accumulation curve reached saturation on the 16th sampling event. Species richness, diversity and evenness differed among the sampled areas. The seasonal curve was not determined by a single unique species, and no single species was the most abundant in all environments sampled. The main vector of Leishmania (Leishmania) infantum, Lutzomyia longipalpis, accounted for only 5.35% of the specimens collected. Proven or suspected vectors of Leishmania (Viannia) braziliensis were recorded, and one female of the cortellezzii complex tested positive for Le. braziliensis DNA. Even with a low infection rate (0.62%), these data indicate the circulation of the parasite and reinforce

  11. Survey of sand flies (Diptera: Psychodidae in an environmentally protected area in Brazil.

    Directory of Open Access Journals (Sweden)

    Lara Saraiva

    Full Text Available Brazil is one of the most important endemic areas for leishmaniasis worldwide. Protected areas that are tourist attractions likely present an important risk of transmission of cutaneous leishmaniasis (CL. Furthermore, with the geographical expansion of visceral leishmaniasis (VL, several studies have recorded the occurrence of its vector, Lutzomyia longipalpis, and cases of human and canine VL in such tourist areas. The Parque Estadual do Sumidouro is an environmentally protected area located in the Brazilian Cerrado biome and in an important area endemic for leishmaniasis in the state of Minas Gerais. The purpose of this study was to monitor the sand fly fauna in areas of tourist activity in the park. Sampling was performed every month, from September 2011 to August 2013, using CDC light traps at six sites of differing environmental characteristics. Sampled specimens were identified following Galati (2003, and females were submitted to molecular techniques for the detection and identification of Leishmania DNA. A total of 4,675 sand fly specimens of 25 species belonging to nine genera were collected. The most abundant species were Micropygomyia quinquefer, Lutzomyia renei and Pintomyia pessoai, although only Pi. pessoai is implicated in the transmission of Leishmania braziliensis. The species accumulation curve reached saturation on the 16th sampling event. Species richness, diversity and evenness differed among the sampled areas. The seasonal curve was not determined by a single unique species, and no single species was the most abundant in all environments sampled. The main vector of Leishmania (Leishmania infantum, Lutzomyia longipalpis, accounted for only 5.35% of the specimens collected. Proven or suspected vectors of Leishmania (Viannia braziliensis were recorded, and one female of the cortellezzii complex tested positive for Le. braziliensis DNA. Even with a low infection rate (0.62%, these data indicate the circulation of the parasite

  12. Sand flies (Diptera, Psychodidae, Phlebotominae from Central Amazonia and four new records for the Amazonas state, Brazil

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    Veracilda R. Alves

    2012-06-01

    Full Text Available Sand flies from Central Amazonia and four new records for the Amazonas state, Brazil. A survey was conducted in May and June 2008 to study the fauna of insects in Central Amazonia, Brazil. As part of the survey, we report here that sixty species of phlebotomine were identified, totaling 13,712 specimens from 13 genera. The collection sites were located at the border between the states of Pará and Amazonas, comprising three municipalities from the Amazonas state (Borba, Maués, and Nhamundá. Malaise, CDC and Shannon traps were used to collect the insects. Most of the sand flies were collected by CDC traps (89.5%, while Malaise and Shannon traps collected 7% and 3.5%, respectively. The most abundant genera, representing 97.1% of the total sand flies identified were: Trichopygomyia Barretto, 1962 (47.6%, Psathyromyia Barretto, 1962 (17.9%, Psychodopygus Mangabeira, 1941 (17.5% and Trichophoromyia Barretto, 1962 (14.3%. The genera with the largest number of species identified were: Psychodopygus (14, Psathyromyia (10, Evandromyia Mangabeira, 1941 (7, Trichophoromyia (5 and Trichopygomyia (5. The most abundant species was Trichopygomyia trichopyga (Floch & Abonnenc, 1945, which represented 29% of the total sand flies identified. Here we also report new records for four species in the Amazonas state: Ps. complexus (Mangabeira, 1941, Ps. llanosmartinsi Fraiha & Ward, 1980, Ty. pinna (Feliciangeli, Ramirez-Pérez & Ramirez, 1989, and Th. readyi (Ryan, 1986. The results of this study provide new, additional information on the distribution of sand flies in the Amazon and increase the number of species in the Amazonas state from 127 to 131.

  13. Irrigation in the arid regions of Tunisia impacts the abundance and apparent density of sand fly vectors of Leishmania infantum.

    Science.gov (United States)

    Barhoumi, Walid; Qualls, Whitney A; Archer, Reginald S; Fuller, Douglas O; Chelbi, Ifhem; Cherni, Saifedine; Derbali, Mohamed; Arheart, Kristopher L; Zhioua, Elyes; Beier, John C

    2015-01-01

    The distribution expansion of important human visceral leishmaniasis (HVL) and sporadic cutaneous leishmaniasis (SCL) vector species, Phlebotomus perfiliewi and P. perniciosus, throughout central Tunisia is a major public health concern. This study was designed to investigate if the expansion of irrigation influences the abundance of sand fly species potentially involved in the transmission of HVL and SCL located in arid bioclimatic regions. Geographic and remote sensing approaches were used to predict the density of visceral leishmaniasis vectors in Tunisia. Entomological investigations were performed in the governorate of Sidi Bouzid, located in the arid bioclimatic region of Tunisia. In 2012, sand flies were collected by CDC light traps located at nine irrigated and nine non-irrigated sites to determine species abundance. Eight species in two genera were collected. Among sand flies of the subgenus Larroussius, P. perfiliewi was the only species collected significantly more in irrigated areas. Trap data were then used to develop Poisson regression models to map the apparent density of important sand fly species as a function of different environmental covariates including climate and vegetation density. The density of P. perfiliewi is predicted to be moderately high in the arid regions. These results highlight that the abundance of P. perfiliewi is associated with the development of irrigated areas and suggests that the expansion of this species will continue to more arid areas of the country as irrigation sites continue to be developed in the region. The continued increase in irrigated areas in the Middle East and North Africa region deserves attention, as it is associated with the spread of L. infantum vector P. perfiliewi. Integrated vector management strategies targeting irrigation structures to reduce sand fly vector populations should be evaluated in light of these findings.

  14. Diversity of the bacterial and fungal microflora from the midgut and cuticle of phlebotomine sand flies collected in North-Western Iran.

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    Mohammad Akhoundi

    Full Text Available BACKGROUND: Phlebotomine sand flies are the vectors of the leishmaniases, parasitic diseases caused by Leishmania spp. Little is known about the prevalence and diversity of sand fly microflora colonizing the midgut or the cuticle. Particularly, there is little information on the fungal diversity. This information is important for development of vector control strategies. METHODOLOGY/PRINCIPAL FINDINGS: FIVE SAND FLY SPECIES: Phlebotomus papatasi, P. sergenti, P. kandelakii, P. perfiliewi and P. halepensis were caught in Bileh Savar and Kaleybar in North-Western Iran that are located in endemic foci of visceral leishmaniasis. A total of 35 specimens were processed. Bacterial and fungal strains were identified by routine microbiological methods. We characterized 39 fungal isolates from the cuticle and/or the midgut. They belong to six different genera including Penicillium (17 isolates, Aspergillus (14, Acremonium (5, Fusarium (1, Geotrichum (1 and Candida (1. We identified 33 Gram-negative bacteria: Serratia marcescens (9 isolates, Enterobacter cloacae (6, Pseudomonas fluorescens (6, Klebsiella ozaenae (4, Acinetobacter sp. (3, Escherichia coli (3, Asaia sp. (1 and Pantoea sp. (1 as well as Gram-positive bacteria Bacillus subtilis (5 and Micrococcus luteus (5 in 10 isolates. CONCLUSION/SIGNIFICANCE: Our study provides new data on the microbiotic diversity of field-collected sand flies and for the first time, evidence of the presence of Asaia sp. in sand flies. We have also found a link between physiological stages (unfed, fresh fed, semi gravid and gravid of sand flies and number of bacteria that they carry. Interestingly Pantoea sp. and Klebsiella ozaenae have been isolated in Old World sand fly species. The presence of latter species on sand fly cuticle and in the female midgut suggests a role for this arthropod in dissemination of these pathogenic bacteria in endemic areas. Further experiments are required to clearly delineate the vectorial

  15. Man-biting sand fly species and natural infection with the Leishmania promastigote in leishmaniasis-endemic areas of Ecuador.

    Science.gov (United States)

    Gomez, Eduardo A; Kato, Hirotomo; Hashiguchi, Yoshihisa

    2014-12-01

    A countrywide surveillance of sand flies was performed to obtain information on their geographical distribution and natural infection by Leishmania protozoa in Ecuador. A total of 18,119 sand flies were collected by human landing collections during 32 years from 1982 to 2014, and 29 species were recognized. The most prevalent 10 species were Lutzomyia gomezi, Lu. robusta, Lu. hartmanni, Lu. shannoni, Lu. trapidoi, Lu. panamensis, Lu. maranonensis, Lu. ayacuchensis, Lu. tortura and Lu. yuilli yuilli, and their topographical and vertical distributions were identified. Among all the sand flies, only 197 (1.09%) flies of four Lutzomyia species, Lu. gomezi, Lu. trapidoi, Lu. tortura and Lu. ayacuchensis, were positive for Leishmania. Endotrypanum, a flagellate parasite not pathogenic to humans, were detected in five Lutzomyia species, Lu. robusta, Lu. hartmanni, Lu. trapidoi, Lu. panamensis and Lu. yuilli yuilli, suggesting wide vector-ranges of Endotrypanum species. These data on the genus Lutzomyia and their natural infections with Leishmania and Endotrypanum will be useful for transmission studies and surveillance of leishmaniasis.

  16. Colonization of Lutzomyia verrucarum and Lutzomyia longipalpis Sand Flies (Diptera: Psychodidae by Bartonella bacilliformis, the Etiologic Agent of Carrion's Disease.

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    James M Battisti

    Full Text Available Bartonella bacilliformis is a pathogenic bacterium transmitted to humans presumably by bites of phlebotomine sand flies, infection with which results in a bi-phasic syndrome termed Carrión's disease. After constructing a low-passage GFP-labeled strain of B. bacilliformis, we artificially infected Lutzomyia verrucarum and L. longipalpis populations, and subsequently monitored colonization of sand flies by fluorescence microscopy. Initially, colonization of the two fly species was indistinguishable, with bacteria exhibiting a high degree of motility, yet still confined to the abdominal midgut. After 48 h, B. bacilliformis transitioned from bacillus-shape to a non-motile, small coccoid form and appeared to be digested along with the blood meal in both fly species. Differences in colonization patterns became evident at 72 h when B. bacilliformis was observed at relatively high density outside the peritrophic membrane in the lumen of the midgut in L. verrucarum, but colonization of L. longipalpis was limited to the blood meal within the intra-peritrophic space of the abdominal midgut, and the majority of bacteria were digested along with the blood meal by day 7. The viability of B. bacilliformis in L. longipalpis was assessed by artificially infecting, homogenizing, and plating for determination of colony-forming units in individual flies over a 13-d time course. Bacteria remained viable at relatively high density for approximately seven days, suggesting that L. longipalpis could potentially serve as a vector. The capacity of L. longipalpis to transmit viable B. bacilliformis from infected to uninfected meals was analyzed via interrupted feeds. No viable bacteria were retrieved from uninfected blood meals in these experiments. This study provides significant information toward understanding colonization of sand flies by B. bacilliformis and also demonstrates the utility of L. longipalpis as a user-friendly, live-vector model system for studying this

  17. Application of RFLP-PCR-Based Identification for Sand Fly Surveillance in an Area Endemic for Kala-Azar in Mymensingh, Bangladesh

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    Mohammad Shafiul Alam

    2012-01-01

    Full Text Available Mymensingh is the most endemic district for kala-azar in Bangladesh. Phlebotomus argentipes remains the only known vector although a number of sand fly species are prevalent in this area. Genotyping of sand flies distributed in a VL endemic area was developed by a PCR and restriction-fragment-length polymorphism (RFLP of 18S rRNA gene of sand fly species. Using the RFLP-PCR analysis with AfaI and HinfI restriction enzymes, P. argentipes, P. papatasi, and Sergentomyia species could be identified. Among 1,055 female sand flies successfully analyzed for the species identification individually, 64.4% flies was classified as Sergentomyia species, whereas 35.6% was identified as P. argentipes and no P. papatasi was found. Although infection of Leishmania within the sand flies was individually examined targeting leishmanial minicircle DNA, none of the 1,055 sand flies examined were positive for Leishmania infection. The RFLP-PCR could be useful tools for taxonomic identification and Leishmania infection monitoring in endemic areas of Bangladesh.

  18. Phlebotomine sand flies (Diptera: Psychodidae) associated with changing patterns in the transmission of the human cutaneous leishmaniasis in French Guiana.

    Science.gov (United States)

    Fouque, Florence; Gaborit, Pascal; Issaly, Jean; Carinci, Romuald; Gantier, Jean-Charles; Ravel, Christophe; Dedet, Jean-Pierre

    2007-02-01

    Between March 2000 and December 2001 a survey of the sand flies (Diptera: Phlebotominae) of French Guiana was carried out during 14 nights of captures with CDC light-traps and Malaise traps, and resulted in the collection of 2245 individuals of 38 species. The most abundant species were Lutzomyia (Trichophoromyia) ininii Floch & Abonnenc, Lu.(Psychodopygus) squamiventris maripaensis Floch & Abonnenc, and Lu .(Nyssomyia) flaviscutellata Mangabeira. Half of the collected sand flies females were dissected under field conditions and five species were found harboring Leishmania-like parasites. The Leishmania (Kinetoplastidae: Trypanosomatidae) species were identified by molecular typing, and for the first time Lu. (Nys.) flaviscutellata was found harboring Leishmania (Viannia) guyanensis and Lu. (Tri) ininii harboring unknown Leishmania. The first record for French Guiana of Lu. (Psy.) squamiventris maripaensis harboring L. (V.) naiffi, was also reported. The patterns of diversification of the human cutaneous leishmaniasis transmission in French Guiana are discussed.

  19. Phlebotomine sand flies (Diptera: Psychodidae associated with changing patterns in the transmission of the human cutaneous leishmaniasis in French Guiana

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    Florence Fouque

    2007-02-01

    Full Text Available Between March 2000 and December 2001 a survey of the sand flies (Diptera: Phlebotominae of French Guiana was carried out during 14 nights of captures with CDC light-traps and Malaise traps, and resulted in the collection of 2245 individuals of 38 species. The most abundant species were Lutzomyia (Trichophoromyia ininii Floch & Abonnenc, Lu.(Psychodopygus squamiventris maripaensis Floch & Abonnenc, and Lu .(Nyssomyia flaviscutellata Mangabeira. Half of the collected sand flies females were dissected under field conditions and five species were found harboring Leishmania-like parasites. The Leishmania (Kinetoplastidae: Trypanosomatidae species were identified by molecular typing, and for the first time Lu. (Nys. flaviscutellata was found harboring Leishmania (Viannia guyanensis and Lu. (Tri ininii harboring unknown Leishmania. The first record for French Guiana of Lu. (Psy. squamiventris maripaensis harboring L. (V. naiffi, was also reported. The patterns of diversification of the human cutaneous leishmaniasis transmission in French Guiana are discussed.

  20. Records and Distribution of New World Phlebotomine Sand Flies (Psychodidae, Diptera), With Special Emphasis on Primary Types and Species Diversity.

    Science.gov (United States)

    Rueda, Leopoldo M; Foley, Desmond H; Pecor, David; Wolkoff, Matthew

    2015-01-01

    This article includes the records and distribution of Phlebotomine sand flies (Psychodidae, Diptera) in the New World based on the specimen collections housed in 2 repositories, the US National Museum of Natural History and the Museum of Entomology, Florida State Collection of Arthropods. Approximately 128 species have primary types housed in the 2 repositories, including holotypes (47 species, 3 subspecies), "types" (7 species), allotypes (52 species, 6 subspecies), lectotypes (4 species), paratypes (93 species, 10 subspecies), and neoallotype (1 species), mounted on slides, with a total of 1,107 type slides. For species diversity, collection data from 24 countries in the sand fly database were analyzed according to the number of species present, specimen records, decade of collections, and countries where collections were conducted.

  1. Lutzomyia sand flies (Diptera: Psychodidae) from middle and lower Putumayo Department, Colombia, with new records to the country.

    Science.gov (United States)

    Barreto, M; Burbano, M E; Barreto, P

    2000-01-01

    A total of 4,840 phlebotomine sand flies from 54 localities in Putumayo department (=state), in the Colombian Amazon region, were collected in Shannon traps, CDC light traps, resting places and from human baits. At least 42 Lutzomyia species were registered for the first time to the department. Psychodopygus and Nyssomyia were the subgenera with the greatest number of taxa, the most common species being L. (N.) yuilli and L. (N.) pajoti. They were sympatric in a wide zone of Putumayo, indicating that they should be treated as full species (new status). Among the anthropophilic sand flies, L. gomezi and L. yuilli were found in intradomiciliar, peridomestic, urban or forest habitats. L. richardwardi, L. claustrei, L. nocticola and L. micropyga are reported for the first time in the Colombian Amazon basin. L. pajoti, L. sipani and L. yucumensis are new records for Colombia.

  2. Lutzomyia sand flies (Diptera: Psychodidae from middle and lower Putumayo department, Colombia, with new records to the country

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    Mauricio Barreto

    2000-10-01

    Full Text Available A total of 4,840 phlebotomine sand flies from 54 localities in Putumayo department (=state, in the Colombian Amazon region, were collected in Shannon traps, CDC light traps, resting places and from human baits. At least 42 Lutzomyia species were registered for the first time to the department. Psychodopygus and Nyssomyia were the subgenera with the greatest number of taxa, the most common species being L. (N. yuilli and L. (N. pajoti. They were sympatric in a wide zone of Putumayo, indicating that they should be treated as full species (new status. Among the anthropophilic sand flies, L. gomezi and L. yuilli were found in intradomiciliar, peridomestic, urban or forest habitats. L. richardwardi, L. claustrei, L. nocticola and L. micropyga are reported for the first time in the Colombian Amazon basin. L. pajoti, L. sipani and L. yucumensis are new records for Colombia.

  3. Leishmaniasis in Central Morocco: Seasonal Fluctuations of Phlebotomine Sand Fly in Aichoun Locality, from Sefrou Province

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    Fatima Zahra Talbi

    2015-01-01

    Full Text Available Cutaneous leishmaniases (CL are endemic in Morocco. They are common in the human population in different localities such as Aichoun in Sefrou province, Morocco. This study was carried out in Aichoun locality from April to October 2012 in order to study the spatiotemporal trends of the main Leishmania phlebotomine vectors in this focus. Overall, 1171 sand flies, belonging to four species, were collected by sticky traps. Phlebotomus sergenti was the predominant species (78.4% followed by Ph. perniciosus (10.5%, Ph. papatasi (7.94%, and Ph. longicuspis (3.16%. Sandflies were active during 6 months (May–October. Ph. sergenti, Ph. perniciosus, and Ph. papatasi displayed a bimodal distribution with a first peak in July and a second peak in September, while Ph. longicuspis showed a monophasic trend with a peak in August. The high abundance and the lengthy period of activity of Ph. sergenti and Ph. perniciosus, vectors of L. tropica and L. infantum, respectively, are a cause for concern as they indicate the high potential risk of Leishmania transmission in the studied areas.

  4. Nestedness patterns of sand fly (Diptera: Psychodidae) species in a neotropical semi-arid environment.

    Science.gov (United States)

    Chaves, Luis Fernando; Añez, Nestor

    2016-01-01

    A common pattern in neotropical Leishmania spp. transmission is the co-occurrence of several sand fly (SF) species at endemic foci. We collected 13 SF spp. by direct aspiration in natural resting places (NRP) and 10 SF spp. with Shannon traps (ST), totaling 15 spp. with both methods, at 6 locations within a semi-arid region with endemic visceral leishmaniasis transmission in Falcón State, Northwestern Venezuela. We used null model testing of species co-occurrence and nestedness metrics estimated with our field data to ask whether SF species composition was segregated/aggregated, and if aggregated whether there was nestedness, i.e., whether species composition across sampling locations could be described by ordered subsets of species from the most species rich location in a landscape. Results showed that SF species were aggregated (Pspecies were present in species rich locations. Similarly, SF species were significantly nested (Pspecies nestedness might be partially shaped by dispersal limitation. Our data showed that three species of medical importance were common across the sampling locations: Lutzomyia gomezi, Lutzomyia panamensis and Lutzomyia evansi, suporting that vector species do not turnover in the studied setting.

  5. Posterior spiracles of fourth instar larvae of four species of phlebotomine sand flies (Diptera: Psychodidae under scanning electron microscopy

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    Pessoa Felipe Arley Costa

    2000-01-01

    Full Text Available In the present study, posterior spiracles of laboratory-reared fourth instar larvae of Lutzomyia longipalpis, L. migonei, L. lenti, and L. whitmani (Diptera: Psychodidae of the State of Ceará, Brazil, were examined under scanning electron microscopy. The number of papillae of spiracles examined varied according to the species examined, but no intraspecific differences were found. The importance of this structure to sand fly larva identification and phylogeny is commented.

  6. Risk Zones of Human Leishmaniases in the Western Mediterranean Basin: Correlations between Vector Sand Flies, Bioclimatology and Phytosociology

    OpenAIRE

    Rispail Philippe; Dereure Jacques; Jarry Daniel

    2002-01-01

    Correspondence analysis was applied to sand fly sampling in 865 stations from the Western Mediterranean basin. The position of each of 24 species was determined with respect to the bioclimatic belts. Thus, the multidimensional analyses manifest clear correlations between bioclimatic belts and their expression in the area, the phytosociological groupings, and vector species of visceral and cutaneous leishmaniases. The transfer of these data to usual maps allows to delimit the geographical dist...

  7. Report on a collection of Lutzomyia sand flies (Diptera: Psychodidae) from the middle Solimões (Amazonas, Brazil)

    OpenAIRE

    Toby Vincent Barrett; Rui Alves de Freitas; Maria Ivonei Carvalho Albuquerque; José Camilo Hurtado Guerrero

    1996-01-01

    Fifty-two species of Lutzomyia sand flies were identified in contemporaneous samples totalling only 1875 individuals, collected at the same site in tall primary terra-firme rainforest, near the south bank of the Solimões River. The most abundant species belonged to the subgenera Trichophoromyia and Nyssomyia. The subgenera Psathyromyia, Nyssomyia and Psychodopygus represented the greatest number of species. A new, aberrant species of the subgenus Psathyromyia (L. cultellata) and the female of...

  8. Lutzomyia sand flies (Diptera: Psychodidae) from middle and lower Putumayo department, Colombia, with new records to the country

    OpenAIRE

    Mauricio Barreto; María Elena Burbano; Pablo Barreto

    2000-01-01

    A total of 4,840 phlebotomine sand flies from 54 localities in Putumayo department (=state), in the Colombian Amazon region, were collected in Shannon traps, CDC light traps, resting places and from human baits. At least 42 Lutzomyia species were registered for the first time to the department. Psychodopygus and Nyssomyia were the subgenera with the greatest number of taxa, the most common species being L. (N.) yuilli and L. (N.) pajoti. They were sympatric in a wide zone of Putumayo, indicat...

  9. Response of Phlebotomine Sand Flies to Light-Emitting Diode-Modified Light Traps in Southern Egypt

    Science.gov (United States)

    2007-04-01

    over incandescent light bulbs include greatly reduced power consumption, cooler operating temperatures , extended operational life, less susceptibility...or two stories high and covered with thatch or brick roofs. Summers are very hot with daily temperatures typically ranging from 24 to 45 C; it seldom...light. Only one study has been performed on a New World sand fly ( Lutzomyia Iongipalpis) measuring spectral sensitivity with an electroretinogram

  10. First report of phlebotomine sand flies (Diptera: Psychodidae) in Kansas and Missouri, and a PCR method to distinguish Lutzomyia shannoni from Lutzomyia vexator.

    Science.gov (United States)

    Weng, Ju-Lin; Young, Samantha L; Gordon, David M; Claborn, David; Petersen, Christine; Ramalho-Ortigao, Marcelo

    2012-11-01

    Sand flies Lutzomyia (Psathyromyia) shannoni (Dyar) and Lu. (Helcocyrtomyia) vexator (Coquillet) were collected for the first time in southwest Missouri and southeast Kansas, expanding the known range of these species in North America. Altogether, 680 sand flies (356 males and 324 females) were collected during trapping from May through October 2011 and identified using morphological characters. Of the total sand flies collected, 315 were identified as Lu. shannoni, with 181 individuals (or 26.6% of all sand flies) trapped in Missouri and 134 individuals (or 19.7%) trapped in Kansas. Whereas 358 Lu. vexator were identified from southwest Missouri, only a single specimen was trapped in southeast Kansas. One male Lu. vexator with asymmetric gonostyli was trapped in Missouri. We also developed a polymerase chain reaction protocol to consistently and accurately distinguish Lu. shannoni from Lu. vexator based on presence or absence of a 416 bp fragment from the cytochrome oxidase c subunit 1 gene.

  11. Impact of Phlebotomine Sand Flies on U.S. Military Operations at Tallil Air Base, Iraq: 3. Evaluation of Surveillance Devices for the Collection of Adult Sand Flies

    Science.gov (United States)

    2007-03-01

    18 attached to a 20- by 7-cm “ cockroach ” sticky trap (Fig. 1). Carbon dioxide or other supplemental attractants were not used. Evaluations were...theMiddle East, it is critical that preventive medicine andvector control personnelmaximize their ability to monitor sand ßy populations, evaluate...Surveillance Monthly Report, U.S. Army Center for Health Promotion and Pre- ventive Medicine 10: 2Ð5. Lewis, D. J. 1971. Phlebotomid sand ßies. Bull

  12. Lipophosphoglycans from Leishmania amazonensis Strains Display Immunomodulatory Properties via TLR4 and Do Not Affect Sand Fly Infection

    Science.gov (United States)

    Nogueira, Paula M.; Assis, Rafael R.; Torrecilhas, Ana C.; Saraiva, Elvira M.; Pessoa, Natália L.; Campos, Marco A.; Marialva, Eric F.; Ríos-Velasquez, Cláudia M.; Pessoa, Felipe A.; Secundino, Nágila F.; Rugani, Jerônimo N.; Nieves, Elsa; Turco, Salvatore J.; Melo, Maria N.

    2016-01-01

    The immunomodulatory properties of lipophosphoglycans (LPG) from New World species of Leishmania have been assessed in Leishmania infantum and Leishmania braziliensis, the causative agents of visceral and cutaneous leishmaniasis, respectively. This glycoconjugate is highly polymorphic among species with variation in sugars that branch off the conserved Gal(β1,4)Man(α1)-PO4 backbone of repeat units. Here, the immunomodulatory activity of LPGs from Leishmania amazonensis, the causative agent of diffuse cutaneous leishmaniasis, was evaluated in two strains from Brazil. One strain (PH8) was originally isolated from the sand fly and the other (Josefa) was isolated from a human case. The ability of purified LPGs from both strains was investigated during in vitro interaction with peritoneal murine macrophages and CHO cells and in vivo infection with Lutzomyia migonei. In peritoneal murine macrophages, the LPGs from both strains activated TLR4. Both LPGs equally activate MAPKs and the NF-κB inhibitor p-IκBα, but were not able to translocate NF-κB. In vivo experiments with sand flies showed that both stains were able to sustain infection in L. migonei. A preliminary biochemical analysis indicates intraspecies variation in the LPG sugar moieties. However, they did not result in different activation profiles of the innate immune system. Also those polymorphisms did not affect infectivity to the sand fly. PMID:27508930

  13. Entomological survey of phlebotomine sand flies (Diptera: Psychodidae in a focus of visceral leishmaniasis in central Iran

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    Mohammad Motovali Emami

    2008-02-01

    Full Text Available Background & objectives: Visceral leishmaniasis (VL is a major vector-borne disease in Iran. A focus of VL is present in Shahreza county, Isfahan province, central Iran. The main objective of this study was to determine the probable vectors in this area. Methods: Sand flies were collected biweekly using sticky paper traps, CDC light-traps, and aspirators from outdoors as well as indoors. All female sand flies were dissected and identified. Promastigotes were inoculated to hamsters and detected by Nested PCR. Approximately 7528 sand flies representing 12 species were collected from April 2003 to October 2004. Phlebotomus (Phlebotomus papatasi Scopoli, Phlebotomus (Larroussious major Annandale and Sergentomyia (Sergentomyia sintoni Pringle were the predominant species. Two percent of P. major was found with natural promastigote infections. Interpretation & conclusion: This is the first report of natural promastigote infection in P. major in central Iran. The activity of P. major started from April and ended in October with a peak in September. The parasites were identified as Leishmania infantum using standard PCR. P. major is a possible vector of leishmaniasis and is susceptible to DDT in this area.

  14. Molecular characterization of leishmania infection from naturally infected sand flies caught in a focus of cutaneous leishmaniasis (eastern iran.

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    Mohammad Akhoundi

    2013-12-01

    Full Text Available Cutaneous leishmaniasis due to Leishmania major is a serious and increasing problem affecting many rural areas of 17 out of 31 provinces in Iran. Little is known about sand fly fauna and leishmaniases in Eastern Iran and no study has been carried out in Sarbisheh County. The aim of this study was to determine sand flies composition and probable Leishmania infection to find the probable vectors of leishmaniasis in Sarbisheh district.Sand flies were caught using both sticky papers and CDC light traps in August 2010. They were identified morphologically and analyzed for Leishmania infection by amplification of ITS-rDNA.Totally, 842 specimens were caught and 8 species recorded. They belonged to the genera Phlebotomus and Sergentomyia: P. (Phlebotomus papatasi, P. (Paraphlebotomus sergenti, P. (Pa. caucasicus, P. (Pa. mongolensis, P. (Pa. jacusieli, S. (Sergentomyia dentata, S. (Se. sintoni and S. (Sintonius clydei. All collected females were processed for Leishmania DNA detection by PCR amplifying of Internal Transcribed Spacer1 (partial sequence, 5.8S (complete sequence and ITS2 (partial sequence fragments. Thirteen females were positive for Leishmania DNA. The sequencing of the 430 bp amplicons indicated that 9 P. papatasi and 3 females belonging to the Caucasicus group carried L. major DNA whereas one P. sergenti carried L. tropica DNA.Phlebotomus papatasi and P. sergenti are, like in several places, the probable vectors of cutaneous leishmaniases in this emerging or unknown focus of cutaneous leishmaniases.

  15. First Human Cases of Leishmania (Viannia) lainsoni Infection and a Search for the Vector Sand Flies in Ecuador

    Science.gov (United States)

    Kato, Hirotomo; Bone, Abdon E.; Mimori, Tatsuyuki; Hashiguchi, Kazue; Shiguango, Gonzalo F.; Gonzales, Silvio V.; Velez, Lenin N.; Guevara, Angel G.; Gomez, Eduardo A.; Hashiguchi, Yoshihisa

    2016-01-01

    An epidemiological study of leishmaniasis was performed in Amazonian areas of Ecuador since little information on the prevalent Leishmania and sand fly species responsible for the transmission is available. Of 33 clinical specimens from patients with cutaneous leishmaniasis (CL), causative parasites were identified in 25 samples based on cytochrome b gene analysis. As reported previously, Leishmania (Viannia) guyanensis and L. (V.) braziliensis were among the causative agents identified. In addition, L. (V.) lainsoni, for which infection is reported in Brazil, Bolivia, Peru, Suriname, and French Guiana, was identified in patients with CL from geographically separate areas in the Ecuadorian Amazon, corroborating the notion that L. (V.) lainsoni is widely distributed in South America. Sand flies were surveyed around the area where a patient with L. (V.) lainsoni was suspected to have been infected. However, natural infection of sand flies by L. (V.) lainsoni was not detected. Further extensive vector searches are necessary to define the transmission cycle of L. (V.) lainsoni in Ecuador. PMID:27191391

  16. First Human Cases of Leishmania (Viannia lainsoni Infection and a Search for the Vector Sand Flies in Ecuador.

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    Hirotomo Kato

    2016-05-01

    Full Text Available An epidemiological study of leishmaniasis was performed in Amazonian areas of Ecuador since little information on the prevalent Leishmania and sand fly species responsible for the transmission is available. Of 33 clinical specimens from patients with cutaneous leishmaniasis (CL, causative parasites were identified in 25 samples based on cytochrome b gene analysis. As reported previously, Leishmania (Viannia guyanensis and L. (V. braziliensis were among the causative agents identified. In addition, L. (V. lainsoni, for which infection is reported in Brazil, Bolivia, Peru, Suriname, and French Guiana, was identified in patients with CL from geographically separate areas in the Ecuadorian Amazon, corroborating the notion that L. (V. lainsoni is widely distributed in South America. Sand flies were surveyed around the area where a patient with L. (V. lainsoni was suspected to have been infected. However, natural infection of sand flies by L. (V. lainsoni was not detected. Further extensive vector searches are necessary to define the transmission cycle of L. (V. lainsoni in Ecuador.

  17. Ecuador Paraiso Escondido Virus, a New Flavivirus Isolated from New World Sand Flies in Ecuador, Is the First Representative of a Novel Clade in the Genus Flavivirus

    OpenAIRE

    Alkan, Cigdem; Zapata, Sonia; Bichaud, Laurence; Moureau, Grégory; Lemey, Philippe; Firth, Andrew E; Tamara S Gritsun; Gould, Ernest A.; de Lamballerie, Xavier; Depaquit, Jérôme; Charrel, Rémi N.

    2015-01-01

    ABSTRACT A new flavivirus, Ecuador Paraiso Escondido virus (EPEV), named after the village where it was discovered, was isolated from sand flies (Psathyromyia abonnenci, formerly Lutzomyia abonnenci) that are unique to the New World. This represents the first sand fly-borne flavivirus identified in the New World. EPEV exhibited a typical flavivirus genome organization. Nevertheless, the maximum pairwise amino acid sequence identity with currently recognized flaviviruses was 52.8%. Phylogeneti...

  18. Efficacy of Different Sampling Methods of Sand Flies (Diptera: Psychodidae in Endemic Focus of Cutaneous Leishmaniasis in Kashan District, Isfahan Province, Iran.

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    Marzieh Hesam-Mohammadi

    2014-12-01

    Full Text Available The aim of the study was to evaluate and compare the efficiency and practicality of seven trapping methods for adult phlebotominae sand flies. The results of this investigation provide information to determine the species composition and nocturnal activity pattern of different sand fly species.The study was carried out in both plain region (about 5km far from northeast and mountainous region (about 40km far from southwest of Kashan City. Seven traps were selected as sampling methods and sand flies were collected during 5 interval times starting July to September 2011 and from 8:00PM to 6:00AM in outdoors habitats. The traps include: sticky traps (4 papers for 2 hours, Disney trap, Malaise, CDC and CO2 light traps, Shannon traps (black and white nets and animal-baited trap.A total of 1445 sand flies belonging to 15 species of Phlebotomus spp. and five of Sergentomyia spp. were collected. Females and males comprised 44.91% and 55.09% of catches, respectively. Of the collected specimens, Se. sintoni was found to be the most prevalent (37.86% species, while Ph. papatasi, accounted for 31.76% of the sand flies.Disney trap and sticky traps exhibited the most productivity than other traps. In addition, in terms of the efficiency of sampling method, these two trapping methods appeared to be the most productive for both estimating the number of sand flies and the species composition in the study area.

  19. Efficacy of light and nonlighted carbon dioxide-baited traps for adult sand fly (Diptera: Psychodidae) surveillance in three counties of Mesrata, Libya.

    Science.gov (United States)

    Obenauer, P J; Annajar, B B; Hanafi, H A; Abdel-Dayem, M S; El-Hossary, S S; Villinski, J

    2012-09-01

    ABSTRACT. Sand flies are important vectors of cutaneous leishmaniasis, especially along coastal towns of northwestern Libya where an estimated 20,000 cases have occurred from 2004 to 2009. Host-seeking traps are an important tool for sampling sand fly populations and surveying the incidence of Leishmania major and L. tropica within a given population. We evaluated the capture efficiency of CO2-baited BG-Sentinel, Centers for Disease Control and Prevention (CDC) light, CDC ultraviolet light, and nonbaited CO2 CDC light traps in 3 coastal townships during June, August, September, and November 2010. A total of 3,248 sand flies, representing 8 species from 2 genera, were collected; most sand flies were identified as either Phlebotomus papatasi or P. longicuspis. Three of the traps captured significantly more sand flies compared to the BG-Sentinel baited with CO2 (P < 0.001). Three of 456 DNA pools extracted from sand flies were positive for Leishmania DNA, indicating a minimum estimated infection rate of 0.83% and 0.47% for P. papatasi and P. longicuspis, respectively.

  20. Immunity to distinct sand fly salivary proteins primes the anti-Leishmania immune response towards protection or exacerbation of disease.

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    Fabiano Oliveira

    Full Text Available BACKGROUND: Leishmania parasites are transmitted in the presence of sand fly saliva. Together with the parasite, the sand fly injects biologically active salivary components that favorably change the environment at the feeding site. Exposure to bites or to salivary proteins results in immunity specific to these components. Mice immunized with Phlebotomus papatasi salivary gland homogenate (SGH or pre-exposed to uninfected bites were protected against Leishmania major infection delivered by needle inoculation with SGH or by infected sand fly bites. Immunization with individual salivary proteins of two sand fly species protected mice from L. major infection. Here, we analyze the immune response to distinct salivary proteins from P. papatasi that produced contrasting outcomes of L. major infection. METHODOLOGY/PRINCIPAL FINDINGS: DNA immunization with distinct DTH-inducing salivary proteins from P. papatasi modulates L. major infection. PpSP15-immunized mice (PpSP15-mice show lasting protection while PpSP44-immunized mice (PpSP44-mice aggravate the infection, suggesting that immunization with these distinct molecules alters the course of anti-Leishmania immunity. Two weeks post-infection, 31.5% of CD4(+ T cells produced IFN-gamma in PpSP15-mice compared to 7.1% in PpSP44-mice. Moreover, IL-4-producing cells were 3-fold higher in PpSP44-mice. At an earlier time point of two hours after challenge with SGH and L. major, the expression profile of PpSP15-mice showed over 3-fold higher IFN-gamma and IL-12-Rbeta2 and 20-fold lower IL-4 expression relative to PpSP44-mice, suggesting that salivary proteins differentially prime anti-Leishmania immunity. This immune response is inducible by sand fly bites where PpSP15-mice showed a 3-fold higher IFN-gamma and a 5-fold lower IL-4 expression compared with PpSP44-mice. CONCLUSIONS/SIGNIFICANCE: Immunization with two salivary proteins from P. papatasi, PpSP15 and PpSP44, produced distinct immune profiles that

  1. Stage-specific adhesion of Leishmania promastigotes to sand fly midguts assessed using an improved comparative binding assay.

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    Raymond Wilson

    Full Text Available BACKGROUND: The binding of Leishmania promastigotes to the midgut epithelium is regarded as an essential part of the life-cycle in the sand fly vector, enabling the parasites to persist beyond the initial blood meal phase and establish the infection. However, the precise nature of the promastigote stage(s that mediate binding is not fully understood. METHODOLOGY/PRINCIPAL FINDINGS: To address this issue we have developed an in vitro gut binding assay in which two promastigote populations are labelled with different fluorescent dyes and compete for binding to dissected sand fly midguts. Binding of procyclic, nectomonad, leptomonad and metacyclic promastigotes of Leishmania infantum and L. mexicana to the midguts of blood-fed, female Lutzomyia longipalpis was investigated. The results show that procyclic and metacyclic promastigotes do not bind to the midgut epithelium in significant numbers, whereas nectomonad and leptomonad promastigotes both bind strongly and in similar numbers. The assay was then used to compare the binding of a range of different parasite species (L. infantum, L. mexicana, L. braziliensis, L. major, L. tropica to guts dissected from various sand flies (Lu. longipalpis, Phlebotomus papatasi, P. sergenti. The results of these comparisons were in many cases in line with expectations, the natural parasite binding most effectively to its natural vector, and no examples were found where a parasite was unable to bind to its natural vector. However, there were interesting exceptions: L. major and L. tropica being able to bind to Lu. longipalpis better than L. infantum; L. braziliensis was able to bind to P. papatasi as well as L. major; and significant binding of L. major to P. sergenti and L. tropica to P. papatasi was observed. CONCLUSIONS/SIGNIFICANCE: The results demonstrate that Leishmania gut binding is strictly stage-dependent, is a property of those forms found in the middle phase of development (nectomonad and leptomonad

  2. Courtship behaviour of Phlebotomus papatasi the sand fly vector of cutaneous leishmaniasis

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    Chelbi Ifhem

    2012-08-01

    Full Text Available Abstract Background The sand fly Phlebotomus papatasi is an Old World vector of Leishmania major, the etiologic agent of zoonotic cutaneous leishmaniasis. This study describes the courtship behaviour of P. papatasi and compares it with that of Lutzomyia longipalpis, the New World vector of visceral leishmaniasis. Understanding the details of courtship behaviour in P. papatasi may help us to understand the role of sex pheromones in this important vector. Results P. papatasi courtship was found to start with the female touching the male, leading him to begin abdomen bending and wing flapping. Following a period of leg rubbing and facing, the male flaps his wings while approaching the female. The female then briefly flaps her wings in response, to indicate that she is willing to mate, thereby signaling the male to begin copulation. Male P. papatasi did not engage in parading behaviour, which is performed by male L. longipalpis to mark out individual territories during lekking (the establishment and maintenance of mating aggregations, or wing-flap during copulation, believed to function in the production of audio signals important to mate recognition. In P. papatasi the only predictor of mating success for males was previous copulation attempts and for females stationary wing-flapping. By contrast, male L. longipalpis mating success is predicted by male approach-flapping and semi-circling behaviour and for females stationary wing-flapping. Conclusions The results show that there are important differences between the mating behaviours of P. papatasi and L. longipalpis. Abdomen bending, which does not occur in L. longipalpis, may act in the release of sex pheromone from an as yet unidentified site in the male abdomen. In male L. longipalpis wing-flapping is believed to be associated with distribution of male pheromone. These different behaviours are likely to signify significant differences in how pheromone is used, an observation that is consistent

  3. Effects of timber harvest on phlebotomine sand flies (Diptera: Psychodidae in a production forest: abundance of species on tree trunks and prevalence of trypanosomatids

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    Felipe Arley Costa Pessoa

    2007-08-01

    Full Text Available The Amazon forest is being exploited for timber production. The harvest removes trees, used by sand flies as resting sites, and decreases the canopy, used as refuges by some hosts. The present study evaluated the impact of the timber harvest, the abundance of sand flies, and their trypanosomatid infection rates before and after selective logging. The study was accomplished in terra-firme production forest in an area of timber harvest, state of Amazonas, Brazil. Sand fly catches were carried out in three areas: one before and after the timber harvest, and two control areas, a nature preservation area and a previously exploited area. The flies were caught by aspiration on tree trunks. Samples of sand flies were dissected for parasitological examination. In the site that suffered a harvest, a larger number of individuals was caught before the selective extraction of timber, showing significant difference in relation to the number of individuals and their flagellate infection rates after the logging. The other two areas did not show differences among their sand fly populations. This fact is suggestive of a fauna sensitive to the environmental alterations associated with selective logging.

  4. First Evidence of a Hybrid of Leishmania (Viannia) braziliensis/L. (V.) peruviana DNA Detected from the Phlebotomine Sand Fly Lutzomyia tejadai in Peru

    Science.gov (United States)

    Hashiguchi, Yoshihisa

    2016-01-01

    The natural infection of sand flies by Leishmania was examined in the Department of Huanuco of Peru, where cutaneous leishmaniasis caused by a hybrid of Leishmania (Viannia) braziliensis/L. (V.) peruviana is endemic. A total of 2,997 female sand flies were captured by CDC light traps and Shannon traps, of which 2,931 and 66 flies were identified as Lutzomyia tejadai and Lu fischeri, respectively. Using crude DNA extracted from individual sand flies as a template, Leishmania DNA was detected from one Lu. tejadai. The parasite species was identified as a hybrid of L. (V.) braziliensis/L. (V.) peruviana on the basis of cytochrome b and mannose phosphate isomerase gene analyses. The result suggested that Lu. tejadai is responsible for the transmission of the hybrid Leishmania circulating in this area. PMID:26735142

  5. First Evidence of a Hybrid of Leishmania (Viannia) braziliensis/L. (V.) peruviana DNA Detected from the Phlebotomine Sand Fly Lutzomyia tejadai in Peru.

    Science.gov (United States)

    Kato, Hirotomo; Cáceres, Abraham G; Hashiguchi, Yoshihisa

    2016-01-01

    The natural infection of sand flies by Leishmania was examined in the Department of Huanuco of Peru, where cutaneous leishmaniasis caused by a hybrid of Leishmania (Viannia) braziliensis/L. (V.) peruviana is endemic. A total of 2,997 female sand flies were captured by CDC light traps and Shannon traps, of which 2,931 and 66 flies were identified as Lutzomyia tejadai and Lu fischeri, respectively. Using crude DNA extracted from individual sand flies as a template, Leishmania DNA was detected from one Lu. tejadai. The parasite species was identified as a hybrid of L. (V.) braziliensis/L. (V.) peruviana on the basis of cytochrome b and mannose phosphate isomerase gene analyses. The result suggested that Lu. tejadai is responsible for the transmission of the hybrid Leishmania circulating in this area.

  6. Evaluation of a metofluthrin fan vaporizer device against phlebotomine sand flies (Diptera: Psychodidae) in a cutaneous leishmaniasis focus in the Judean Desert, Israel.

    Science.gov (United States)

    Zollner, Gabriela; Orshan, Laor

    2011-03-01

    The OFF! Clip-On fan vaporizer device releasing metofluthrin was evaluated against phletobomine sand flies in the Judean Desert, Israel, in October, 2009. A total of 76,400 sand flies was collected, with male flies representing 98.3%Phlebotomus sergenti and 1.7%P. papatasi. Females comprised 43.0% of the total catch and included 6.7% blood-fed females. Similar proportions of flies were collected in both suction and sticky traps. In trials with unbaited suction traps, similar numbers of sand flies were collected in traps with a metofluthrin device, blank device, or no device (i.e., suction only). In suction traps baited with CO(2) , higher numbers of P. sergenti males and blood-fed females were collected in traps with a blank device compared to traps with a metofluthrin device. In sticky traps baited with CO(2) , there were no significant differences between catches in traps with a metofluthrin device, blank device, or no device. The results suggest metofluthrin from the device is not repellent against sand flies in a field environment despite showing insecticidal activity against flies collected in suction traps.

  7. Entomological studies of phlebotomine sand flies (Diptera: Psychodidae) in relation to cutaneous leishmaniasis transmission in Al Rabta, North West of Libya.

    Science.gov (United States)

    Dokhan, Mostafa Ramahdan; Kenawy, Mohamed Amin; Doha, Said Abdallah; El-Hosary, Shabaan Said; Shaibi, Taher; Annajar, Badereddin Bashir

    2016-02-01

    Al Rabta in the North-West of Libya is a rural area where cutaneous leishmaniasis (CL) is endemic for long time. Few reports are available on sand flies in this area which is an important focus of CL. Therefore, this study aimed at updating the species composition, and monthly fluctuation of sand flies in this area. Sand flies were biweekly collected by CDC light traps from June to November 2012 and April to November 2013 in two villages, Al Rabta East (RE) and Al Rabta West (RW). Nine species (6 Phlebotomus and 3 Sergentomyia) were reported in the two villages. A total of 5605 and 5446 flies were collected of which Phlebotomus represented 59.30 and 56.63% in RE and RW, respectively. Sergentomyia minuta and Phlebotomus papatasi were the abundant species. Generally, more males were collected than females for all species. The overall ratios (males: females) for most of species were not deviated from the expected 1:1 ratio (Chi-squared, P>0.05). Sand fly abundance (fly/trap) is directly related to the temperature and RH (P0.05). Flies were active from April to November with increased activity from June to October. Prominent peaks were in September and June. The abundance of P. papatasi and Phlebotomus sergenti, vectors of CL (August-October) coincided with the reported higher numbers of CL cases (August- November). The obtained results could be important for the successful planning and implementation of leishmaniasis control programs.

  8. Molecular detection of Leishmania in phlebotomine sand flies (Diptera: Psychodidae) from a cutaneous leishmaniasis focus atXakriabá Indigenous Reserve, Brazil.

    Science.gov (United States)

    Rêgo, Felipe Dutra; Rugani, Jeronimo Marteleto Nunes; Shimabukuro, Paloma Helena Fernandes; Tonelli, Gabriel Barbosa; Quaresma, Patrícia Flávia; Gontijo, Célia Maria Ferreira

    2015-01-01

    Autochthonous cases of American cutaneous leishmaniasis (ACL) have been reported since 2001 in the Xakriabá Indigenous Reserve located in the municipality of São João das Missões in northern Minas Gerais state, Brazil. In order to study the presence of Leishmania DNA in phlebotomine sand flies, six entomological collections were carried out from July 2008 through July 2009, using 40 light traps placed in peridomicile areas of 20 randomly selected houses. From October 2011 through August 2012, another six collections were carried out with 20 light traps distributed among four trails (five traps per trail) selected for a previous study of wild and synanthropic hosts of Leishmania. A total of 4,760 phlebotomine specimens were collected belonging to ten genera and twenty-three species. Single female specimens or pools with up to ten specimens of the same locality, species and date, for Leishmania detection by molecular methods. Species identification of parasites was performed with ITS1 PCR-RFLP using HaeIII enzyme and genetic sequencing for SSU rRNA target. The presence of Leishmania DNA was detected in eleven samples from peridomicile areas: Lu. longipalpis (two), Nyssomyia intermedia (four), Lu. renei (two), Lu. ischnacantha, Micropygomyia goiana and Evandromyia lenti (one pool of each specie). The presence of Leishmania DNA was detected in twelve samples from among the trails: Martinsmyia minasensis (six), Ny. intermedia (three), Mi. peresi (two) and Ev. lenti (one). The presence of Leishmania infantum DNA in Lu. longipalpis and Leishmania braziliensis DNA in Ny. intermediasupport the epidemiological importance of these species of sand flies in the cycle of visceral and cutaneous leishmaniasis, respectively. The results also found other species associated with Leishmania DNA, such as Mt. minasensis and Ev. lenti, which may participate in a wild and/or synanthropic cycle of Leishmania transmission in the studied area.

  9. Identification of Sand flies of the Subgenus Larroussius based on Molecular and Morphological Characters in North Western Iran

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    A Absavaran

    2009-12-01

    Full Text Available Background: The adult female sand flies (Diptera: Psychodidae of the subgenus Larroussius are important vectors of Leishmania infantum (Kinetoplastida: Tripanosomatidae in Meshkinshahr district, Northwest of Iran. Four Phle­boto­mus (Larroussius species are present in this area, i.e. Phlebotomus (Larroussius kandelakii, P. (La. major, P. (La. perfiliewi and P. (La. tobbi. The objective of the present study was to identify and distinguish the females of P. per­filiewi, P. major and P. tobbi, in this district.Methods: Adult sand flies were collected with sticky papers, CDC light traps, and aspirator in 2006. Individual sand flies of this four species from thirty different locations were characterized morphologically and by comparative DNA se­quences analyses of a fragment of mitochondrial gene Cytochrome b (Cyt b and nuclear gene Elongation Factor 1- al­pha (EF-1α. PCR amplification was carried out for all three species P. major, P. perfiliewi and P. tobbi in the sub­ge­nus Larroussius.Results: Phylogenetic analyses of P. major populations in this study displayed two different populations and genetic di­ver­sity. Spermathecal segment number, pharyngeal armature and other morphological characters of these three spe­cies were examined and found to present consistent interspecific differences.Conclusion: According to our findings, the phylogeny of Cyt b and EF-1α haplotypes confirms the relationships be­tween P. major, P. tobbi and P. perfiliewi as already defined by their morphological similarities.

  10. Enhanced protective efficacy of nonpathogenic recombinant leishmania tarentolae expressing cysteine proteinases combined with a sand fly salivary antigen.

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    Farnaz Zahedifard

    2014-03-01

    Full Text Available BACKGROUND: Novel vaccination approaches are needed to prevent leishmaniasis. Live attenuated vaccines are the gold standard for protection against intracellular pathogens such as Leishmania and there have been new developments in this field. The nonpathogenic to humans lizard protozoan parasite, Leishmania (L tarentolae, has been used effectively as a vaccine platform against visceral leishmaniasis in experimental animal models. Correspondingly, pre-exposure to sand fly saliva or immunization with a salivary protein has been shown to protect mice against cutaneous leishmaniasis. METHODOLOGY/PRINCIPAL FINDINGS: Here, we tested the efficacy of a novel combination of established protective parasite antigens expressed by L. tarentolae together with a sand fly salivary antigen as a vaccine strategy against L. major infection. The immunogenicity and protective efficacy of different DNA/Live and Live/Live prime-boost vaccination modalities with live recombinant L. tarentolae stably expressing cysteine proteinases (type I and II, CPA/CPB and PpSP15, an immunogenic salivary protein from Phlebotomus papatasi, a natural vector of L. major, were tested both in susceptible BALB/c and resistant C57BL/6 mice. Both humoral and cellular immune responses were assessed before challenge and at 3 and 10 weeks after Leishmania infection. In both strains of mice, the strongest protective effect was observed when priming with PpSP15 DNA and boosting with PpSP15 DNA and live recombinant L. tarentolae stably expressing cysteine proteinase genes. CONCLUSION/SIGNIFICANCE: The present study is the first to use a combination of recombinant L. tarentolae with a sand fly salivary antigen (PpSP15 and represents a novel promising vaccination approach against leishmaniasis.

  11. Enhanced Protective Efficacy of Nonpathogenic Recombinant Leishmania tarentolae Expressing Cysteine Proteinases Combined with a Sand Fly Salivary Antigen

    Science.gov (United States)

    Taheri, Tahereh; Taslimi, Yasaman; Doustdari, Fatemeh; Seyed, Negar; Torkashvand, Fatemeh; Meneses, Claudio; Papadopoulou, Barbara; Kamhawi, Shaden; Valenzuela, Jesus G.; Rafati, Sima

    2014-01-01

    Background Novel vaccination approaches are needed to prevent leishmaniasis. Live attenuated vaccines are the gold standard for protection against intracellular pathogens such as Leishmania and there have been new developments in this field. The nonpathogenic to humans lizard protozoan parasite, Leishmania (L) tarentolae, has been used effectively as a vaccine platform against visceral leishmaniasis in experimental animal models. Correspondingly, pre-exposure to sand fly saliva or immunization with a salivary protein has been shown to protect mice against cutaneous leishmaniasis. Methodology/Principal Findings Here, we tested the efficacy of a novel combination of established protective parasite antigens expressed by L. tarentolae together with a sand fly salivary antigen as a vaccine strategy against L. major infection. The immunogenicity and protective efficacy of different DNA/Live and Live/Live prime-boost vaccination modalities with live recombinant L. tarentolae stably expressing cysteine proteinases (type I and II, CPA/CPB) and PpSP15, an immunogenic salivary protein from Phlebotomus papatasi, a natural vector of L. major, were tested both in susceptible BALB/c and resistant C57BL/6 mice. Both humoral and cellular immune responses were assessed before challenge and at 3 and 10 weeks after Leishmania infection. In both strains of mice, the strongest protective effect was observed when priming with PpSP15 DNA and boosting with PpSP15 DNA and live recombinant L. tarentolae stably expressing cysteine proteinase genes. Conclusion/Significance The present study is the first to use a combination of recombinant L. tarentolae with a sand fly salivary antigen (PpSP15) and represents a novel promising vaccination approach against leishmaniasis. PMID:24675711

  12. Strength Properties of Fly Ash Based Geopolymer Concrete with Sea Sand

    OpenAIRE

    2016-01-01

    The production of every ton of cement contributes to production of one ton of CO2. With the development of infra activities, the power sector activities are also increasing. The coal based power plant produces huge quantity of fly ash, which creates its disposal problems. However to some extent, the fly ash is used as partial substitution to cement. The alkali activated fly ash concrete (Geopolymer Concrete) proposed by Devidovits, shows considerable promise for application in construction in...

  13. A Sand Fly Salivary Protein Vaccine Shows Efficacy Against Vector-Transmitted Cutaneous Leishmaniasis in Nonhuman Primates

    Science.gov (United States)

    2015-06-03

    8-98) Prescribed by ANSI Std Z39-18 21 days. Most NHP (63%) developed a delayed type hypersensitivity (DTH) re sponse showing a marked recruitment...and penicillin /streptomycin (2 mg/ml). Cells were cultured in 96 well plates at 1 × 106 cells/ml in a final volume of 200 ml and incubated with...Sissoko, R. M. Fairhurst, M. P. Fay, J. M. Anderson, S. Doumbia, S. Kamhawi, J. G. Valenzuela, Delayed type hypersensitivity to sand fly saliva in

  14. Risk zones of human Leishmaniases in the Western Mediterranean basin: correlations between vector sand flies, bioclimatology and phytosociology.

    Science.gov (United States)

    Rispail, Philippe; Dereure, Jacques; Jarry, Daniel

    2002-06-01

    Correspondence analysis was applied to sand fly sampling in 865 stations from the Western Mediterranean basin. The position of each of 24 species was determined with respect to the bioclimatic belts. Thus, the multidimensional analyses manifest clear correlations between bioclimatic belts and their expression in the area, the phytosociological groupings, and vector species of visceral and cutaneous leishmaniases. The transfer of these data to usual maps allows to delimit the geographical distribution of these diseases in the Western Mediterranean basin and contributes to the determination, in a rational manner, of the high risk zones.

  15. Report on a collection of Lutzomyia sand flies (Diptera: Psychodidae from the middle Solimões (Amazonas, Brazil

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    Toby Vincent Barrett

    1996-02-01

    Full Text Available Fifty-two species of Lutzomyia sand flies were identified in contemporaneous samples totalling only 1875 individuals, collected at the same site in tall primary terra-firme rainforest, near the south bank of the Solimões River. The most abundant species belonged to the subgenera Trichophoromyia and Nyssomyia. The subgenera Psathyromyia, Nyssomyia and Psychodopygus represented the greatest number of species. A new, aberrant species of the subgenus Psathyromyia (L. cultellata and the female of Lu. souzacastroi are described. The Phlebotominae are proposed as a suitable indicator group for biogeographic and diversity studies.

  16. Molecular characterization of Leishmania infection in sand flies from Al-madinah Al-munawarah province, western Saudi Arabia.

    Science.gov (United States)

    El-Beshbishy, Hesham A; Al-Ali, Khalil H; El-Badry, Ayman A

    2013-06-01

    Cutaneous leishmaniasis (CL) is caused by various species of the genus Leishmania. The disease is considered a major health problem in different areas of Saudi Arabia including Al-madinah Al-munawarah province. We aimed to identify Leishmania species isolated from sand fly vectors by molecular analysis. Sand fly sampling was carried out from May 2010 to October 2010 in province of Al-madinah Al-munawarah from four different localities. Female sand flies collected were subjected to DNA extraction followed by molecular analysis using the semi-nested PCR and conventional PCR protocols, respectively, against minicircle kDNA and ribosomal internal transcribed spacer 1 (ITS1-rDNA). The PCR positive specimens against ITS1-rDNA locus were digested for further confirmation of species identification. A total of 2910 sand flies were collected. Phlebotomus papatasi accounted for 93.8% (1673 males and 1057 females), however, the number of Phlebotomus sergenti was only 180 (109 males and 71 females). Sixty-two out of 250 (23.7%) female P. papatasi tested for Leishmania parasite were positive for Leishmania major using the semi-nested PCR method against kDNA. All of the 62 positive specimens produced a band size 650 bp. A 31% of female P. sergenti were positive against kDNA of Leishmania tropica and produced a 720 bp band. These positive P. sergenti for L. tropica DNA produced ITS1-PCR-RFLP profile showed two bands of ∼200 bp and 57 bp which are specific for L. tropica, confirming the presence of L. tropica in P. sergenti. However, the ITS1-PCR-RFLP profile showed two bands of ∼203 bp and 132 bp which are specific for L. major in P. papatasi. We concluded that, the semi-nested PCR method against kDNA and the ITS1-PCR-RFLP analysis are useful tools for molecular identification of both L. major and L. tropica. A multicenter study is necessary in order to evaluate the extent of the disease and functional analysis of new Leishmania genes.

  17. Temporal distribution and behaviour of sand flies (Diptera: Psychodidae) in a cutaneous leishmaniasis focus of the Kani Tribe settlements in the Western Ghats, India.

    Science.gov (United States)

    Srinivasan, R; Jambulingam, P; Kumar, N Pradeep; Selvakumar, M; Edwin, B; Kumar, T Dilip

    2015-08-01

    The temporal distribution of sand flies in relation to environmental factors was studied in the Kani tribe settlements located on the southernmost part of the Western Ghats, Kerala, India, between June 2012 and May 2013. This area is known for occurrence of cutaneous leishmaniasis (CL) cases. Employing hand-held aspirator, light trap and sticky-trap collection methods, a total of 7874 sand fly specimens, comprising 19 species was collected. Sergentomyia baghdadis was predominant species, followed by Phlebotomus argentipes. Sand fly abundance was significantly higher indoors (χ(2)=9241.8; p=0.0001) than outdoors. Mean density of P. argentipes in human dwellings, cattle sheds and outdoors was 7.2±2.9, 27.33±21.1 and 0.64±0.2 females/per man-hour (MHR), respectively. No sand fly species other than P. argentipes was obtained from cattle sheds. Although, sand fly populations were prevalent throughout the year, their abundance fluctuated with seasonal changes. Multiple regression analysis with backward elimination indicated that the increase in precipitation and relative humidity contributed to a significant positive association with the increase in sand fly abundance, while the increase in temperature showed no association. Fully engorged female sand flies tested for blood meal source showed multiple host-blood feeding. Analysis of resting populations of sand flies collected from human shelters indicated that the populations were found maximum on interior walls at 6-8 and >8 ft height, including ceiling during summer (F=83.7, df=6, p=0.001) and at the lower half of the wall at 0 and 0-2 ft height, during monsoon season (F=41.4, df=6, p=0.001). In cooler months, no preference to any height level (F=1.67, df=6, p=0.2) was observed. Proportion of females sand flies with Sella's classification of abdominal stages, namely full-fed, half-gravid and gravid females did not vary significantly (t=1.98, p=0.13827) indoors, confirming their endophilic behaviour. Risk of CL

  18. A summary of the evidence for the change in European distribution of phlebotomine sand flies (Diptera: Psychodidae) of public health importance.

    Science.gov (United States)

    Medlock, Jolyon M; Hansford, Kayleigh M; Van Bortel, Wim; Zeller, Herve; Alten, Bulent

    2014-06-01

    The phlebotomine sand flies (Diptera: Psychodidae, Phlebotominae) are vectors of several infectious pathogens. The presence of a sand fly vector is considered to be a risk factor for the emergence of leishmaniasis in temperate Europe. Hence, the occurrence of phlebotomine sand flies and any changes in their distribution is important in determining the potential change in distribution of leishmaniasis in Europe. Therefore, published evidence for a changing distribution of the important phlebotomine sand fly vectors of leishmaniasis and phlebovirus infection in Europe is reviewed. This paper presents evidence of an increasing risk of establishment by sand fly species, especially for the Atlantic Coast and inland parts of Germany, Switzerland, and Austria. In addition to detection in potentially appropriate areas, the findings show areas of potential future establishment of the species. The most important and urgent necessity within the community of entomologists working on phlebotomines is the need to record the extremes of distribution of each species and obtain data on their regional presence/absence along with increased sharing of the data throughout European projects.

  19. Study on Sand Flies as a Vector(s of Cutaneous Leishmaniasis by Nested PCR in Rural Areas of Damghan District, Semnan Province

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    Y. Rasi

    2012-01-01

    Full Text Available Introduction & Objective: Cutaneous Leishmaniasis is caused by obligatory intracellular parasite of genus Lieshmania. The disease is reported from more than half of Iran's provinces. Various species of sand flies are vector of the disease. Determination of vectors and gaining knowledge about them are important for devising of control program. Materials & Methods: This survey was performed as a cross-sectional study in order to determine the vector(s of cutaneous leishmaniasis in Damghan district during 2008-2009. Sand flies were collected from indoors and outdoors by sticky traps twice in month from April to November. Head and last abdominal segments of the samples were removed and mounted in a drop of Puri’s medium and identified. The rest of the sand flies' bodies was subjected to DNA extraction for molecular detection of Leishmania parasite by Nested PCR using specific primers of minicircle kinetoplast DNAResults: Totally, 6110 sand flies in 8 species were collected. P. papatasi had high density (46.7%. Examination of 280 female sand flies by Nested PCR showed that 28 sand flies (10%include 24 specimens P.papatasi (85.7% and 4 specimens P.caucasicus(14.3%were found naturally infected with L.major. The highest rate of infected sandflies were observed in rodents burrow (42.9%. Maximum rate of sand fly infection was in September (89.3%. Conclusion: With respect to high density of P.papatasi and isolation of L.major from it, this species was the main vector of the disease. Detection of L.major from P.caucasicus shows that this species was the secondary vector in rodent burrow. The highest rate of sand leis infected was in September, so personal protection in this month is very important and necessary. Regarding to the high density of vectors and high infection rate of them taking actions to decrease the sand fly abundance and prevention of human biting are suggested.(Sci J Hamadan Univ Med Sci 2012;18(4:47-52

  20. MOLECULAR DETECTION OF Leishmania IN PHLEBOTOMINE SAND FLIES IN A CUTANEOUS AND VISCERAL LEISHMANIASIS ENDEMIC AREA IN NORTHEASTERN BRAZIL

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    Vanessa Cristina Fitipaldi Veloso Guimarães

    2014-07-01

    Full Text Available Several phlebotomine sand fly species have been regarded as putative or proven vectors of parasites of the genus Leishmania in Brazil, but data for the northeastern region remains incipient. In this study, a total of 600 phlebotomine sand flies were grouped in pools of 10 specimens each and tested by a Leishmania genus-specific PCR and by a PCR targeting Leishmania (Leishmania infantum. Fourteen out of 60 pools were positive by the genus-specific PCR, being five pools of L. migonei, seven of L. complexa, one of L. sordellii and one of L. naftalekatzi, which correspond to a minimal infection rate of 2.3% (14/600. Our results, associated with their known anthropophily and their abundance, suggest the participation of L. migonei and L. complexa as vectors of Leishmania in northeastern Brazil. Remarkably, this is the first time in this country that the detection of Leishmania DNA in L. sordellii and L. naftalekatzi has been reported, but future studies are necessary to better understand the significance of these findings.

  1. SAND FLIES (DIPTERA: PSYCHODIDAE) IN AN ENDEMIC AREA OF LEISHMANIASIS IN AQUIDAUANA MUNICIPALITY, PANTANAL OF MATO GROSSO DO SUL , BRAZIL

    Science.gov (United States)

    de FIGUEIREDO, Helen Rezende; SANTOS, Mirella Ferreira da Cunha; CASARIL, Aline Etelvina; INFRAN, Jucelei Oliveira de Moura; RIBEIRO, Leticia Moraes; FERNANDES, Carlos Eurico dos Santos; de OLIVEIRA, Alessandra Gutierrez

    2016-01-01

    SUMMARY The Aquidauana municipality is considered an endemic area of leishmaniasis and an important tourist site in Mato Grosso do Sul State. The aim of this study was to investigate the sand fly fauna in the city of Aquidauana. Captures were carried out twice a month, from April 2012 to March 2014 with automatic light traps and active aspiration, in the peridomicile and domicile of six residences. A total of 9,338 specimens were collected, 3,179 and 6,159 using light traps and active aspiration, respectively. The fauna consisted of: Brumptomyia brumpti, Evandromyia aldafalcaoae, Ev. evandroi, Ev. lenti, Ev. orcyi, Ev. sallesi, Ev. termitophila, Ev. walkeri, Lutzomyia longipalpis and Psathyromyia bigeniculata. The most abundant species captured was Lutzomyia longipalpis, present in all the ecotopes, predominantly in peridomicile areas, and mainly males. Leishmania DNA was not detected in the insects. It was observed the abundance of the sand fly fauna in the region, as well as the high frequency of Lu. longipalpis, the main vector of L. infantum. The results of this study show the need to increase the monitoring and more effective control measures. It is noteworthy that the studied region presents several activities related to tourism and recreation, increasing the risk of transmission of leishmaniasis to this particular human population. PMID:27982353

  2. High stenghth concrete with high cement substitution by adding fly ash, CaCO3, silica sand, and superplasticizer

    Science.gov (United States)

    Wicaksono, Muchammad Ridho Sigit; Qoly, Amelia; Hidayah, Annisaul; Pangestuti, Endah Kanti

    2017-03-01

    Concrete is a mixture of cement, fine aggregate, coarse aggregate and water with or without additives. Concrete can be made with substitution of cement with materials like Fly Ash, CaCO3 and silica sand that can increase the binding on pasta and also increase the compressive strength of concrete. The Superplasticizer on a mixture is used to reduce the high water content, improve concrete durability, low permeability concrete by making it more resilient, and improve the quality of concrete. The combination between Fly Ash (30% of cement required), CaCO3 (10% of cement required) and silica sand (5% of cement required) with added MasterGlenium ACE 8595 as much as 1,2% from total cement will produces compressive strength of up to 1080 kN/cm2 or 73,34 Mpa when the concrete is aged at 28 day. By using this technique and innovation, it proves that the cost reduction is calculated at 27%, which is much more efficient. While the strength of the concrete is increased at 5% compared with normal mixture.

  3. Rotation of the external genitalia in male Phlebotomine sand flies (Diptera, Psychodidae) in laboratory conditions and in captured specimens in Algarve, Portugal.

    Science.gov (United States)

    Ferrolho, J; Maia, C; Gomes, J; Alves-Pires, C; Cristóvão, J M; Campino, L; Afonso, M O

    2015-10-01

    Protozoal parasites are the causative agents of many insect-borne infectious diseases worldwide with impact on human and animal health. Leishmaniasis is caused by Leishmania spp. and transmitted by female Phlebotomine sand flies. In Portugal, two species of Phlebotomus (Larroussius), namely Phlebotomus perniciosus and Phlebotomus ariasi are the proven vectors of Leishmania infantum. Phlebotomine females and males rest and breed in the same sites; and these locations can be predicted according to the male external genitalia maturation. Therefore, this study aimed to determine the timing of complete rotation of the male external genitalia in laboratory conditions and to characterize the external genitalia rotation in field captured males to predict the male and female sand fly breeding and resting sites. This knowledge can be applied in the design and implementation of integrated sand fly control strategies targeting these sites.

  4. Lutzomyia sand fly diversity and rates of infection by Wolbachia and an exotic Leishmania species on Barro Colorado Island, Panama.

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    Jorge Azpurua

    Full Text Available BACKGROUND: Sand flies (Diptera, Psychodidae, Phlebotominae in the genus Lutzomyia are the predominant vectors of the protozoan disease leishmaniasis in the New World. Within the watershed of the Panama Canal, the cutaneous form of leishmaniasis is a continuous health threat for residents, tourists and members of an international research community. Here we report the results of screening a tropical forest assemblage of sand fly species for infection by both Leishmania and a microbe that can potentially serve in vector population control, the cytoplasmically transmitted rickettsia, Wolbachia pipientis. Knowing accurately which Lutzomyia species are present, what their evolutionary relationships are, and how they are infected by strains of both Leishmania and Wolbachia is of critical value for building strategies to mitigate the impact of this disease in humans. METHODOLOGY AND FINDINGS: We collected, sorted and then used DNA sequences to determine the diversity and probable phylogenetic relationships of the Phlebotominae occurring in the understory of Barro Colorado Island in the Republic of Panama. Sequence from CO1, the DNA barcoding gene, supported 18 morphology-based species determinations while revealing the presence of two possible "cryptic" species, one (Lu. sp. nr vespertilionis within the Vespertilionis group, the other (Lu. gomezi within the Lutzomyia-cruciata series. Using ITS-1 and "minicircle" primers we detected Leishmania DNA in 43.3% of Lu. trapidoi, 26.3% of Lu. gomezi individuals and in 0% of the other 18 sand fly species. Identical ITS-1 sequence was obtained from the Leishmania infecting Lu. trapidoi and Lu. gomezi, sequence which was 93% similar to Leishmania (viannia naiffi in GenBank, a species previously unknown in Panama, but recognized as a type of cutaneous leishmaniasis vectored broadly across northern and central South America. Distinct strains of the intracellular bacterium Wolbachia were detected in three of 20

  5. Chicken blood provides a suitable meal for the sand fly Lutzomyia longipalpis and does not inhibit Leishmania development in the gut

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    Cavalcante Reginaldo R

    2010-01-01

    Full Text Available Abstract Background The aim of this study was to address the role of chickens as bloodmeal sources for female Lutzomyia longipalpis and to test whether chicken blood is harmful to Leishmania parasite development within the sand flies. Bloodmeal ingestion, excretion of urate, reproduction, fecundity, as well as Leishmania infection and development were compared in sand flies fed on blood from chickens and different mammalian sources. Results Large differences in haemoglobin and protein concentrations in whole blood (dog>human>rabbit> chicken did not correlate with differences in bloodmeal protein concentrations (dog = chicken>human>rabbit. This indicated that Lu. longipalpis were able to concentrate bloodmeals taken from different hosts using prediuresis and this was confirmed by direct observation. Sand flies fed on chickens or dogs produced significantly more eggs than those fed on human blood. Female Lu. longipalpis retained significantly more urate inside their bodies when fed on chicken blood compared to those fed on rabbit blood. However, when the amounts of urate excreted after feeding were measured, sand flies fed on rabbit blood excreted significantly more than those fed on chicken blood. There was no difference in female longevity after feeding on avian or mammalian blood. Sand flies infected via chicken blood produced Leishmania mexicana infections with a similar developmental pattern but higher overall parasite populations than sand flies infected via rabbit blood. Conclusions The results of this study help to define the role that chickens play in the epidemiology of leishmaniasis. The present study using a Lu. longipalpis/L. mexicana model indicates that chickens are suitable hosts to support a Lu. longipalpis population and that chicken blood is likely to support the development of transmissible Leishmania infections in Lu. longipalpis.

  6. Phenology and population dynamics of sand flies in a new focus of visceral leishmaniasis in Eastern Azarbaijan Province, North western of Iran

    Institute of Scientific and Technical Information of China (English)

    Teimour Hazratian; Yavar Rassi; Mohammad Ali Oshaghi; Mohammad Reza Yaghoobi-Ershadi; Esmael Fallah; Mohammad Reza Shirzadi; Sina Rafizadeh

    2011-01-01

    Objective:To investigate species composition, density, accumulated degree-day and diversity of sand flies during April to October2010in Azarshahr district, a new focus of visceral leishmaniasis in north western Iran.Methods: Sand flies were collected using sticky traps biweekly and were stored in96% ethanol. All specimens were mounted in Puri's medium for species identification using valid keys of sandflies. The density was calculated by the formula: number of specimens/m2 of sticky traps and number of specimens/ number of traps. Degree-day was calculated as follows: (Maximum temperature + Minimum temperature)/2-Minimum threshold. Diversity indices of the collected sand flies within different villages were estimated by s the Shannon- weaver formula (H'=ΣPilogePi i=1 ).Results:Totally5 557 specimens comprising 16Species (14Phlebotomus, and 2Sergentomyia) were indentified. The activity of the species extended from April to October. Common sand-flies in resting places werePhlebotomus papatasi, Phlebotomus sergenti andPhlebotomus mongolensis. The monthly average density was 37.6, 41.1, 40.23, 30.38 and30.67 for Almalodash, Jaragil, Segaiesh, Amirdizaj and Germezgol villages, respectively. Accumulated degree-day from early January to late May was approximately289 degree days. The minimum threshold temperature for calculating of accumulated degree-day was17.32℃. According on the Shannon-weaver (H'), diversity of sand flies within area study were estimated as0.917, 1.867, 1.339, 1.673, and1.562in Almalodash, Jaragil, Segaiesh, Amirdizaj and Germezgol villages, respectively.Conclusions: This study is the first detailed research in terms of species composition, density, accumulated degree-day and diversity of sand flies in an endemic focus of visceral leishamaniasis in Azarshahr district. The population dynamics of sand flies in Azarshahr district were greatly affected by climatic factors. According to this study the highest activity of the collected sand fly species

  7. Opening Ceremony of American Flying Tiger Guilin Heritage Park Held

    Institute of Scientific and Technical Information of China (English)

    Li; Sanghua; Ba; Cuicui; Jin; Hanghang

    2015-01-01

    On March 28,Chinese Vice Premier Liu Yandong attended the opening of the Flying Tiger Guilin Heritage Park in Guilin,southwest China’s Guangxi Zhuang Autonomous Region whose construction started in July 2011.Located at the former site of Yang Tang Airport,it has such historical relics as the Command Post

  8. Identification of Sand flies of the Subgenus Larroussius based on Molecular and Morphological Characters in North Western Iran

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    A Absavaran

    2009-12-01

    Full Text Available Background: The adult female sand flies (Diptera: Psychodidae of the subgenus Larroussius are important vectors of Leishmania infantum (Kinetoplastida: Tripanosomatidae in Meshkinshahr district, Northwest of Iran. Four Phle­boto­mus (Larroussius species are present in this area, i.e. Phlebotomus (Larroussius kandelakii, P. (La. major, P. (La. perfiliewi and P. (La. tobbi. The objective of the present study was to identify and distinguish the females of P. per­filiewi, P. major and P. tobbi, in this district."nMethods: Adult sand flies were collected with sticky papers, CDC light traps, and aspirator in 2006. Individual sand flies of this four species from thirty different locations were characterized morphologically and by comparative DNA se­quences analyses of a fragment of mitochondrial gene Cytochrome b (Cyt b and nuclear gene Elongation Factor 1- al­pha (EF-1α. PCR amplification was carried out for all three species P. major, P. perfiliewi and P. tobbi in the sub­ge­nus Larroussius."nResults: Phylogenetic analyses of P. major populations in this study displayed two different populations and genetic di­ver­sity. Spermathecal segment number, pharyngeal armature and other morphological characters of these three spe­cies were examined and found to present consistent interspecific differences."nConclusion: According to our findings, the phylogeny of Cyt b and EF-1α haplotypes confirms the relationships be­tween P. major, P. tobbi and P. perfiliewi as already defined by their morphological similarities.                                                                                  Keywords: Phlebotomus, Larroussius, Cytochrome b, Elongation Factor-1α, Morphology, Iran                 

  9. Sand Flies of the Subgenus Adlerius (Diptera: Psychodidae in an Endemic Focus of Visceral Leishmaniasis and Introduction of Phlebotomus (Adlerius comatus as a New Record for Iran.

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    Ali Reza Zahraei-Ramazani

    2013-06-01

    Full Text Available Sand flies of subgenus Adlerius has a wide geographical distribution in Iran and are mostly found in wild form in mountainous areas. They are always considered as probable vectors of visceral leishmaniasis. The objective of this study was to determine the Adlerius species and its composition in an endemic focus of zoonotic visceral leishmaniasis in northwest of the country.Sand flies were collected from 6 different areas of Azarbaijan-e-Sharqi Province using sticky paper traps from August to September which is active season for sand flies in this area, in 2009. The flies were mounted and identified. The length of third antennal segments, ascoid, labrum, coxite, surstyle, style, aedeagus, genital filament, genital pump, width of style, and the end of aedeagus were measured and the number of costal hairs group was also counted as the morphological characters.A total of 30 adult sand flies, (26 males and 4 females including Phlebotomus halepensis (46.8%, P. longiductus (13.3%, P. balcanicus (23.3%, P. comatus (3.3%, and Adlerius spp. (13.3% belong to subgenus Adlerius were identified respectively in 6 counties. One P. comatus male was captured in front of a cave located in the hillside of a mountain covered with the vegetation in Varzeqan area.The presence of at least 5 species of the subgenus Adlerius in Azarbaijan-e-Sharqi Province, an endemic focus of zoonotic visceral leishmaniasis in Iran, shows that the risk of parasite transmission among man and reservoir animals is high during the active season of sand flies. P. comatus is a new record for Iran and needs to be added to the list of Iranian phlebotomines of subgenus Adlerius.

  10. Landscape associations of the sand fly, Lutzomyia (Heleocyrtomyia) apache (Diptera: Psychodidae), in the southwestern United States: a geographic information system analysis.

    Science.gov (United States)

    Herrero, M V; Yarnell, W E; Schmidtmann, E T

    2004-12-01

    Landscape associations of the sand fly, Lutzomyia apache, Young and Perkins, in the southwestern U.S. were investigated by light/suction trap sampling and the development of a GIS-generated distribution map. In the mid-Rio Grande River valley, N.M., female and male L. apache were captured in updraft light/suction traps set in desert shrubland, irrigation levee, and bosque vegetation communities. Small numbers of flies were captured, but the presence of males and females in spatially separate and diverse plant communities at two locations suggest that L. apache are dispersed among available vegetation types. These data, along with 22 previously published collection site records, were used with a suite of physiographic features to characterize the biogeographic conditions suitable for L. apache. Suitable conditions encompass three life zones: the Rocky Mountain steppe province, the Colorado semi-plateau province, and the American semi-desert province, all within the dry domain region of the western U.S. The potential range of L. apache was then estimated based on elevation, mean and max - min temperature, precipitation, wet days, and relative humidity. The estimated range includes large contiguous areas in north-central Colorado, east-central New Mexico and west Texas, the lower mid-Rio Grande River valley, and southern Arizona, along with smaller, patchy, areas in northern Arizona, California, Nevada, Utah, and central Idaho. The spatial relationship between the estimated distribution of L. apache and the location of livestock exposed to vesicular stomatitis virus at the onset of recent outbreaks is presented.

  11. Efficacy of Commercial Mosquito Traps in Capturing Phlebotomine Sand Flies (Diptera: Psychodidae) in Egypt

    Science.gov (United States)

    2010-01-01

    baited trap, carbondioxide ,BG-Sentinel trap,MosquitoMagnetPro trap,Phlebotomus papatasi Disease-carrying phlebotomine sand ßies cause an es- timated... strip supplied with the trap was not used because octenol has not been shown to be attractive to P. papatasi in Egypt (Beavers et al. 2004). The MCU trap

  12. Effect of Lures and Trap Placement on Sand Fly and Mosquito Traps

    Science.gov (United States)

    2008-01-01

    Phlebotomus guggisbergi, a vector of Leishmania tropica in Kenya. Med. Vet. Entomol. 7:216-218. Killick-Kendrick, R. 1999. The biology and control...Acta Tropica 101:106-114. Hoel, D.E, Butler, J.F., Fawaz, E.Y., Watany, N., El-Hossary, S.S., and Villinski, J. 2007. Response of phlebotomine sand

  13. [An updated checklist of Phlebotomine sand flies (Diptera: Psychodidae: Phlebotominae) from the Colombian Andean coffee-growing region].

    Science.gov (United States)

    Contreras-Gutiérrez, María Angélica; Vélez, Iván Darío; Porter, Charles; Uribe, Sandra Inés

    2014-01-01

    An updated list of phlebotomine sand flies species in coffee growing areas in the Colombian Andean region is presented. Fifty three species were reported from 12 departments. In addition, species distribution in the region was derived from specimens obtained during intensive field work in five departments, from previously published studies and from the taxonomic revision of specimens in the entomological collection of the Programa de Estudio y Control de Enfermedades Tropicales (PECET). The list includes the genera Brumptomyia (2 species), Lutzomyia (50 species) and Warileya (1 species). The updated list contains eleven new records in the region under study, including Lutzomyia panamensis , a species of medical importance not recorded previously in this zone. Eighteen of the species are considered to be anthropophilic, and many of them have been implicated in the transmission of leishmaniasis.

  14. Notes on the Phlebotomine Sand Flies from the Peruvian Southeast : I. Description of Lutzomyia (Helcocyrtomyia adamsi n. sp. (Diptera: Psychodidae

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    Fernandez R

    1998-01-01

    Full Text Available A new species of phlebotomine sand fly, Lutzomyia adamsi n. sp., is described and illustrated from specimens collected during August 1994, in Sandia, Department of Puno-Peru. According to the Oficina Nacional de Evaluacion de Recursos Naturales(ONERN 1976, this locality is situated in the life zone known as humid, mountain, low tropical forest (bh-MBT. Many areas in the northern part of Puno, mainly in the Inambari and Tambopata basins, are endemic to leishmaniasis. These areas are the continuation of others, largely known as "leishmaniasic" in the departments of Cusco and Madre de Dios. The morphological characteristics indicated that this species belongs to the genus Lutzomyia, subgenus Helcocyrtomyia Barretto, 1962

  15. Impact of phlebotomine sand flies on U.S. Military operations at Tallil Air Base, Iraq: 1. background, military situation, and development of a "Leishmaniasis Control Program".

    Science.gov (United States)

    Coleman, Russell E; Burkett, Douglas A; Putnam, John L; Sherwood, Van; Caci, Jennifer B; Jennings, Barton T; Hochberg, Lisa P; Spradling, Sharon L; Rowton, Edgar D; Blount, Keith; Ploch, John; Hopkins, Grady; Raymond, Jo-Lynne W; O'Guinn, Monica L; Lee, John S; Weina, Peter J

    2006-07-01

    One of the most significant modern day efforts to prevent and control an arthropod-borne disease during a military deployment occurred when a team of U.S. military entomologists led efforts to characterize, prevent, and control leishmaniasis at Tallil Air Base (TAB), Iraq, during Operation Iraqi Freedom. Soon after arriving at TAB on 22 March 2003, military entomologists determined that 1) high numbers of sand flies were present at TAB, 2) individual soldiers were receiving many sand fly bites in a single night, and 3) Leishmania parasites were present in 1.5% of the female sand flies as determined using a real-time (fluorogenic) Leishmania-generic polymerase chain reaction assay. The rapid determination that leishmaniasis was a specific threat in this area allowed for the establishment of a comprehensive Leishmaniasis Control Program (LCP) over 5 mo before the first case of leishmaniasis was confirmed in a U.S. soldier deployed to Iraq. The LCP had four components: 1) risk assessment, 2) enhancement of use of personal protective measures by all personnel at TAB, 3) vector and reservoir control, and 4) education of military personnel about sand flies and leishmaniasis. The establishment of the LCP at TAB before the onset of any human disease conclusively demonstrated that entomologists can play a critical role during military deployments.

  16. First detection of Leishmania tropica DNA and Trypanosoma species in Sergentomyia sand flies (Diptera: Psychodidae from an outbreak area of cutaneous leishmaniasis in Ghana.

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    Chukwunonso O Nzelu

    2014-02-01

    Full Text Available BACKGROUND: Leishmania major and an uncharacterized species have been reported from human patients in a cutaneous leishmaniasis (CL outbreak area in Ghana. Reports from the area indicate the presence of anthropophilic Sergentomyia species that were found with Leishmania DNA. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we analyzed the Leishmania DNA positive sand fly pools by PCR-RFLP and ITS1 gene sequencing. The trypanosome was determined using the SSU rRNA gene sequence. We observed DNA of L. major, L. tropica and Trypanosoma species to be associated with the sand fly infections. This study provides the first detection of L. tropica DNA and Trypanosoma species as well as the confirmation of L. major DNA within Sergentomyia sand flies in Ghana and suggests that S. ingrami and S. hamoni are possible vectors of CL in the study area. CONCLUSIONS/SIGNIFICANCE: The detection of L. tropica DNA in this CL focus is a novel finding in Ghana as well as West Africa. In addition, the unexpected infection of Trypanosoma DNA within S. africana africana indicates that more attention is necessary when identifying parasitic organisms by PCR within sand fly vectors in Ghana and other areas where leishmaniasis is endemic.

  17. Blood-meal identification in phlebotomine sand flies (Diptera: Psychodidae) from Valle Hermoso, a high prevalence zone for cutaneous leishmaniasis in Ecuador.

    Science.gov (United States)

    Anaguano, David F; Ponce, Patricio; Baldeón, Manuel E; Santander, Stephanie; Cevallos, Varsovia

    2015-12-01

    Cutaneous leishmaniasis is a neglected tropical disease transmitted by phlebotomine sand flies of the genus Lutzomyia. In South America, cutaneous leishmaniasis is endemic in the majority of countries. There are no previous reports of phlebotomine sand fly host feeding sources in Ecuador. We identified blood meal sources for phlebotomine sand fly species in Valle Hermoso, a hyper endemic area for leishmaniasis in Ecuador. Phlebotomine sand fly collections were carried out during the dry and rainy seasons. PCR and multiplex PCR were performed from DNA extracted from the abdomens of blood-fed females to specifically identify the avian and mammalian blood meal sources. Avian-blood (77%), mammalian-blood (16%) and mixed avian-mammalian blood (7%) were found in the samples. At the species level, blood from chickens (35.5%), humans (2.8%), cows (2.8%) and dogs (1.9%) was specifically detected. Nyssomyia trapidoi was the most common species of Lutzomyia found that fed on birds. The present results may aid the development of effective strategies to control leishmaniasis in Ecuador.

  18. Spatial distribution of sand fly species (Psychodidae: Phlebtominae), ecological niche, and climatic regionalization in zoonotic foci of cutaneous leishmaniasis, southwest of Iran.

    Science.gov (United States)

    Ebrahimi, Sahar; Bordbar, Ali; Rastaghi, Ahmad R Esmaeili; Parvizi, Parviz

    2016-06-01

    Cutaneous leishmaniasis (CL) is a complex vector-borne disease caused by Leishmania parasites that are transmitted by the bite of several species of infected female phlebotomine sand flies. Monthly factor analysis of climatic variables indicated fundamental variables. Principal component-based regionalization was used for recognition of climatic zones using a clustering integrated method that identified five climatic zones based on factor analysis. To investigate spatial distribution of the sand fly species, the kriging method was used as an advanced geostatistical procedure in the ArcGIS modeling system that is beneficial to design measurement plans and to predict the transmission cycle in various regions of Khuzestan province, southwest of Iran. However, more than an 80% probability of P. papatasi was observed in rainy and temperate bio-climatic zones with a high potential of CL transmission. Finding P. sergenti revealed the probability of transmission and distribution patterns of a non-native vector of CL in related zones. These findings could be used as models indicating climatic zones and environmental variables connected to sand fly presence and vector distribution. Furthermore, this information is appropriate for future research efforts into the ecology of Phlebotomine sand flies and for the prevention of CL vector transmission as a public health priority.

  19. Species composition, activity patterns and blood meal analysis of sand fly populations (Diptera: Psychodidae) in the metropolitan region of Thessaloniki, an endemic focus of canine leishmaniasis

    Science.gov (United States)

    Species composition, activity patterns and blood meal analysis of sand fly populations were investigated in the metropolitan region of Thessaloniki, North Greece from May to October 2011. Sampling was conducted weekly in 3 different environments (animal facilities, open fields, residential areas) al...

  20. Diversity and Dynamics of Sand Flies (Diptera: Psychodidae of Two Cutaneous Leishmaniasis Foci in the Fes-Boulemane Region of Northern Morocco

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    Fatima Zahra Talbi

    2015-01-01

    Full Text Available Cutaneous leishmaniasis (CL is an infectious disease caused by various species of Leishmania and transmitted by several species of sand flies (Diptera: Psychodidae. In order to evaluate the risk of leishmaniasis transmission in Fes-Boulemane, an investigation was carried out in two localities, Aichoun and Bouasseme, during 2011. From January to December, 1120 specimens were collected in Aichoun comprising six species belonging to two genera: Phlebotomus sergenti (76.07%, Phlebotomus longicuspis (9.01%, Phlebotomus perniciosus (8.48%, Phlebotomus papatasi (4.82%, Sergentomyia minuta, and Sergentomyia fallax. For Bouasseme, seven species were identified with Phlebotomus sergenti (60.39% dominating, followed by Phlebotomus perniciosus (20% and Phlebotomus longicuspis (12.15%. The remaining species, Phlebotomus papatasi, Phlebotomus ariasi, Sergentomyia minuta, and Sergentomyia fallax, were less prevalent. The activity of sand flies in both localities is marked by the dominance of Ph. sergenti with two peaks occurring in June and September. In order to obtain a better understanding of sand fly diversity among their species, results were analyzed by the ecological indices determinant: specific richness, the relative abundance, and Shannon-Weiner index (H′. Further studies of sand fly diversity should employ statistical tests and molecular analyses. This study can be useful in the implementation of appropriate future control measures.

  1. Efficacy and duration of three residual insecticides on cotton duck and vinyl tent surfaces for control of the sand fly Phlebotomus papatasi (Diptera: Psychodidae)

    Science.gov (United States)

    Many military tents are made of vinyl and cotton duck. Because it is useful to treat exterior tent surfaces to manage phlebotomine sand flies, DoD and ARS scientists evaluated the efficacy of 3 residual insecticides on both tent fabrics. P. papatasi was effectively killed by shade-stored and sun-exp...

  2. Phlebotomine sand flies (Diptera: Psychodidae) in the municipality of Várzea Grande: an area of transmission of visceral leishmaniasis in the state of Mato Grosso, Brazil.

    Science.gov (United States)

    Missawa, Nanci Akemi; Dias, Edelberto Santos

    2007-12-01

    Visceral leishmaniasis (VL) has been naturally transmitted in periurban areas due to the emergence and reemergence of its vectors in such areas. Aimed to further knowledge on ecological aspects affecting the occurrence of phlebotomine sand flies in VL transmission areas in the municipality of Várzea Grande, state of Mato Grosso (MT), Brazil, sand fly captures were carried out. Monthly collections of sand flies were undertaken with CDC light-traps, which were left in both intradomiciliary and peridomiciliary areas of ten residences during four consecutive days between January 2004 and June 2006. Twenty-two species of genus Lutzomyia and one of Brumptomyia were captured. The most abundant species was Lutzomyia longipalpis (65.23%), followed by L. evandroi (16.26%), L. lenti (7.69%), L. whitmani (4.92%), L. sallesi (2.34%) and L. termitophila (1.32%). The highest density of the main VL vector, L. longipalpis, was found in peridomiciliary areas, mostly males. No significant correlation was found between environment (temperature, air relative humidity and rain fall) and phlebotomine density; although a slight increase in sand fly density has been observed in the period following rainfalls, particularly L. longipalpis. No correlation was observed between distribution and density of L. longipalpis, prevalence of human VL cases and the presence of serologically positive dogs. The presence of infected dogs, increased vector density, susceptibility rate and interruption of epidemiological surveillance may raise the risk of VL transmission to man in Várzea Grande.

  3. Phlebotomine sand flies (Diptera: Psychodidae in the municipality of Várzea Grande: an area of transmission of visceral leishmaniasis in the state of Mato Grosso, Brazil

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    Nanci Akemi Missawa

    2007-12-01

    Full Text Available Visceral leishmaniasis (VL has been naturally transmitted in periurban areas due to the emergence and reemergence of its vectors in such areas. Aimed to further knowledge on ecological aspects affecting the occurrence of phlebotomine sand flies in VL transmission areas in the municipality of Várzea Grande, state of Mato Grosso (MT, Brazil, sand fly captures were carried out. Monthly collections of sand flies were undertaken with CDC light-traps, which were left in both intradomiciliary and peridomiciliary areas of ten residences during four consecutive days between January 2004 and June 2006. Twenty-two species of genus Lutzomyia and one of Brumptomyia were captured. The most abundant species was Lutzomyia longipalpis (65.23%, followed by L. evandroi (16.26%, L. lenti (7.69%, L. whitmani (4.92%, L. sallesi (2.34% and L. termitophila (1.32%. The highest density of the main VL vector, L. longipalpis, was found in peridomiciliary areas, mostly males. No significant correlation was found between environment (temperature, air relative humidity and rain fall and phlebotomine density; although a slight increase in sand fly density has been observed in the period following rainfalls, particularly L. longipalpis. No correlation was observed between distribution and density of L. longipalpis, prevalence of human VL cases and the presence of serologically positive dogs. The presence of infected dogs, increased vector density, susceptibility rate and interruption of epidemiological surveillance may raise the risk of VL transmission to man in Várzea Grande.

  4. Seasonality of sand flies (Diptera: Psychodidae) and Leishmania DNA detection in vector species in an area with endemic visceral leishmaniasis

    Science.gov (United States)

    Saraiva, Lara; Leite, Camila Gonçalves; Lima, Ana Cristina Vianna Mariano da Rocha; de Carvalho, Luiz Otávio Alves; Pereira, Agnes Antônia Sampaio; Rugani, Jerônimo Marteleto Nunes; Rego, Felipe Dutra; Gontijo, Célia Maria Ferreira; Andrade, José Dilermando

    2017-01-01

    BACKGROUND Leishmaniases are a serious health problem in southeast Brazil, including the city of Belo Horizonte (BH), Minas Gerais state (MG), where there are high rates of incidence and mortality due to visceral leishmaniases. BH is divided into nine sanitary districts (SD) of which one, the Venda Nova SD, was selected for this study because it has high rates of positivity for canine leishmaniasis and high incidence of human leishmaniasis. OBJECTIVES This study aimed to survey the sand fly fauna in Venda Nova SD from August 2011 to July 2013 and perform a descriptive analysis of the vector population. METHODS The sampling was carried out using automatic HP light traps at all covered areas of the Venda Nova SD, in a total of eighteen light traps. Sampled specimens were identified following Galati (2003), and females were submitted to molecular techniques for the detection and identification of Leishmania DNA. A simple environmental description was done for it area and Kernel estimation was used to infer vector density for each study site. FINDINGS A total of 2,427 sand fly specimens belonging to eight species and five genera were collected of which 95.3% were Lutzomyia longipalpis. The seasonal variation curve was delineated by this species. Lu. longipalpis was the most abundant at all collection points and in all months of the study, and exhibited a natural infection rate of 1.01% for Leishmania infantum and 1.77% for Leishmania braziliensis. MAIN CONCLUSIONS The results show the presence and adaptation of Lu. longipalpis to the anthropic environment of BH and reinforces its role as the main vector of L. infantum in the region. PMID:28327794

  5. Evidence for anthropophily in five species of phlebotomine sand flies (Diptera: Psychodidae) from northern Colombia, revealed by molecular identification of bloodmeals.

    Science.gov (United States)

    Paternina, Luís E; Verbel-Vergara, Daniel; Romero-Ricardo, Luís; Pérez-Doria, Alveiro; Paternina-Gómez, Margaret; Martínez, Lily; Bejarano, Eduar E

    2016-01-01

    Identification of the bloodmeal sources of phlebotomine sand flies is fundamental to determining which species are anthropophilic and understanding the transmission of Leishmania parasites in natural epidemiological settings. The objective of this study was to identify sand fly bloodmeals in the mixed leishmaniasis focus of the department of Sucre, northern Colombia. In all 141 engorged female sand flies were analyzed, after being captured in intradomiciliary, peridomiciliary and extradomiciliary habitats with Shannon and CDC traps and by active searching in diurnal resting sites. Bloodmeals were identified by sequencing and analysis of a 358bp fragment of the mitochondrial gene Cytochrome b (CYB) and a 330bp fragment of the nuclear gene prepronociceptin (PNOC). Using both genes 105 vertebrate bloodmeals were identified, with an efficiency of 72% for CYB but only 7% for PNOC. Ten species of vertebrates were identified as providing bloodmeal sources for 8 sand fly species: Homo sapiens (Lutzomyia evansi, Lutzomyia panamensis, Lutzomyia micropyga, Lutzomyia shannoni and Lutzomyia atroclavata), Equus caballus (L. evansi, L. panamensis and Lutzomyia cayennensis cayennensis), Equus asinus (L. evansi and L. panamensis), Bos taurus (L. evansi, L. panamensis and L. c. cayennensis), Tamandua mexicana (L. shannoni and Lutzomyia trinidadensis), Proechimys guyanensis (L. evansi, L. panamensis and L. c. cayennensis), Mabuya sp. (Lutzomyia micropyga), Anolissp. (L. micropyga), Sus scrofa (L. evansi and Lutzomyia gomezi) and Gallus gallus (L. evansi). Cattle, donkeys, humans and pigs were significantly more important than other animals (P=0.0001) as hosts of L. evansi, this being the most abundant sand fly species. The five Lutzomyia species in which blood samples of human origin were detected included L. micropyga and L. atroclavata, constituting the first evidence of anthropophily in both species.

  6. A phylogenetic lineage of closely related trypanosomes (Trypanosomatidae, Kinetoplastida) of anurans and sand flies (Psychodidae, Diptera) sharing the same ecotopes in brazilian amazonia.

    Science.gov (United States)

    Ferreira, Robson C; De Souza, Adelson A; Freitas, Rui A; Campaner, Marta; Takata, Carmem S A; Barrett, Toby V; Shaw, Jeffrey J; Teixeira, Marta M G

    2008-01-01

    Analysis of the phylogenetic relationships among trypanosomes from vertebrates and invertebrates disclosed a new lineage of trypanosomes circulating among anurans and sand flies that share the same ecotopes in Brazilian Amazonia. This assemblage of closely related trypanosomes was determined by comparing whole SSU rDNA sequences of anuran trypanosomes from the Brazilian biomes of Amazonia, the Pantanal, and the Atlantic Forest and from Europe, North America, and Africa, and from trypanosomes of sand flies from Amazonia. Phylogenetic trees based on maximum likelihood and parsimony corroborated the positioning of all new anuran trypanosomes in the aquatic clade but did not support the monophyly of anuran trypanosomes. However, all analyses always supported four major clades (An01-04) of anuran trypanosomes. Clade An04 is composed of trypanosomes from exotic anurans. Isolates in clades An01 and An02 were from Brazilian frogs and toads captured in the three biomes studied, Amazonia, the Pantanal and the Atlantic Forest. Clade An01 contains mostly isolates from Hylidae whereas clade An02 comprises mostly isolates from Bufonidae; and clade An03 contains trypanosomes from sand flies and anurans of Bufonidae, Leptodactylidae, and Leiuperidae exclusively from Amazonia. To our knowledge, this is the first study describing morphological and growth features, and molecular phylogenetic affiliation of trypanosomes from anurans and phlebotomines, incriminating these flies as invertebrate hosts and probably also as important vectors of Amazonian terrestrial anuran trypanosomes.

  7. Colonization of Lutzomyia verrucarum and Lutzomyia longipalpis Sand Flies (Diptera: Psychodidae) by Bartonella bacilliformis, the Etiologic Agent of Carrión's Disease.

    Science.gov (United States)

    Battisti, James M; Lawyer, Phillip G; Minnick, Michael F

    2015-01-01

    Bartonella bacilliformis is a pathogenic bacterium transmitted to humans presumably by bites of phlebotomine sand flies, infection with which results in a bi-phasic syndrome termed Carrión's disease. After constructing a low-passage GFP-labeled strain of B. bacilliformis, we artificially infected Lutzomyia verrucarum and L. longipalpis populations, and subsequently monitored colonization of sand flies by fluorescence microscopy. Initially, colonization of the two fly species was indistinguishable, with bacteria exhibiting a high degree of motility, yet still confined to the abdominal midgut. After 48 h, B. bacilliformis transitioned from bacillus-shape to a non-motile, small coccoid form and appeared to be digested along with the blood meal in both fly species. Differences in colonization patterns became evident at 72 h when B. bacilliformis was observed at relatively high density outside the peritrophic membrane in the lumen of the midgut in L. verrucarum, but colonization of L. longipalpis was limited to the blood meal within the intra-peritrophic space of the abdominal midgut, and the majority of bacteria were digested along with the blood meal by day 7. The viability of B. bacilliformis in L. longipalpis was assessed by artificially infecting, homogenizing, and plating for determination of colony-forming units in individual flies over a 13-d time course. Bacteria remained viable at relatively high density for approximately seven days, suggesting that L. longipalpis could potentially serve as a vector. The capacity of L. longipalpis to transmit viable B. bacilliformis from infected to uninfected meals was analyzed via interrupted feeds. No viable bacteria were retrieved from uninfected blood meals in these experiments. This study provides significant information toward understanding colonization of sand flies by B. bacilliformis and also demonstrates the utility of L. longipalpis as a user-friendly, live-vector model system for studying this severely neglected

  8. Molecular typing of sand fly species (Diptera, Psychodidae, Phlebotominae) from areas endemic for Leishmaniasis in Ecuador by PCR-RFLP of 18S ribosomal RNA gene.

    Science.gov (United States)

    Terayama, Yoshimi; Kato, Hirotomo; Gomez, Eduardo A; Uezato, Hiroshi; Calvopiña, Manuel; Iwata, Hiroyuki; Hashiguchi, Yoshihisa

    2008-09-01

    Surveillance of the distribution of sand fly species is important for prediction of the risk and expansion of Leishmania infection in endemic and surrounding areas. In the present study, a simple and reliable method of typing New World Lutzomyia species circulating in endemic areas in Ecuador was established by using polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) technique. PCR-RFLP of 18S ribosomal RNA (rRNA) genes with the restriction enzyme AfaI and subsequently HinfI successfully identified seven sand fly species in nine endemic areas in Ecuador. Although intraspecific genetic-diversity affecting the RFLP-patterns was detected in a species, the patterns were species specific. The method promises to be a powerful tool for the classification of New World Lutzomyia species.

  9. Assessment of sand fly (Diptera, Psychodidae) control using cypermethrin in an endemic area for visceral leishmaniasis, Montes Claros, Minas Gerais State, Brazil.

    Science.gov (United States)

    Barata, Ricardo Andrade; Michalsky, Erika Monteiro; Fujiwara, Ricardo Toshio; França-Silva, João Carlos; Rocha, Marília Fonseca; Dias, Edelberto Santos

    2011-11-01

    Montes Claros in Minas Gerais State, Brazil, was considered an intense transmission area for visceral leishmaniasis. This study evaluated sand fly fauna after insecticide application. Captures were performed in 10 districts from September 2005 to August 2006 with CDC light traps inside and outside each residence. Cypermethrin was sprayed in two cycles during November/2005 and May/2006. The 636 specimens collected, belonging to 10 species, were predominantly Lutzomyia longipalpis (79%), and most frequently males (70%). The highest percentage of specimens were captured in areas surrounding domiciles (85.8%). The main species were observed to be sensitive to treatment with the insecticide. The results showed a reduction in the number of sand flies collected after use of cypermethrin in homes and annexes, and with residual effect lasting from two to four months.

  10. A Cross-Sectional Survey of Knowledge, Attitude and Practices Related to Cutaneous Leishmaniasis and Sand Flies in Punjab, Pakistan.

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    Ayesha Akram

    Full Text Available Recent outbreaks of cutaneous leishmaniasis make the disease a public health concern in Punjab, Pakistan. The knowledge of how the population perceives the disease and its vector is essential in order to design an effective management strategy, but such studies are rare in Pakistan.The present study was based on a cross-sectional self-administered survey comprising 250 household samples collected from five localities including Bhawalpur, Multan, Jhang, Faisalabad and Lahore. The results revealed that the respondents had a poor knowledge of the vector and disease. Few of the respondents were aware about the identification of sand flies, their breeding place, biting time, transmission of leishmaniasis and control measures. Skin infection and sandflies as the main disease symptom and vector of the disease, respectively, were known to some of the respondents. Some believed that summer was the main peak incidence of the disease and it could be transmitted from man to man via contact. However, most of the respondents believed that the disease could be cured. Admission to hospitals, cleanliness and use of bed nets were the treatment measures for the disease in suspected patients, whereas some thought that the use of bed nets could be helpful in preventing leishmaniasis infection.Poor knowledge of the disease and its vector in the study population emphasize the need to initiate health education and awareness campaigns to minimize the risks of cutaneous leishmaniasis outbreaks in the future.

  11. Study of sand flies (Diptera: Psychodidae) in visceral and cutaneous leishmaniasis areas in the central-western state of Minas Gerais, Brazil.

    Science.gov (United States)

    Nascimento, Bruno Warlley Leandro; Saraiva, Lara; Neto, Rafael Gonçalves Teixeira; Meira, Paula Cavalcante Lamy Serra e; Sanguinette, Cristiani de Castilho; Tonelli, Gabriel Barbosa; Botelho, Helbert Antônio; Belo, Vinícius Silva; Silva, Eduardo Sérgio da; Gontijo, Célia Maria Ferreira; Filho, José Dilermando Andrade

    2013-03-01

    The transmission of Leishmania involves several species of sand flies that are closely associated with various parasites and reservoirs, with differing transmission cycles in Brazil. A study on the phlebotomine species composition has been conducted in the municipality of Divinópolis, Minas Gerais, Brazil, an endemic area for cutaneous leishmaniasis (CL), which has intense occurrence of visceral leishmaniasis (VL) cases. In order to study the sand flies populations and their seasonality, CDC light traps (HP model) were distributed in 15 houses which presented at least one case of CL or VL and in five urban parks (green areas). Collections were carried out three nights monthly from September 2010 to August 2011. A total of 1064 phlebotomine specimens were collected belonging to two genera and seventeen species: Brumptomyia brumpti, Lutzomyia bacula, Lutzomyia cortelezzii, Lutzomyia lenti, Lutzomyia sallesi, Lutzomyia longipalpis, Lutzomyia migonei, Lutzomyia intermedia, Lutzomyia neivai, Lutzomyia whitmani, Lutzomyia christenseni, Lutzomyia monticola, Lutzomyia pessoai, Lutzomyia aragaoi, Lutzomyia brasiliensis, Lutzomyia lutziana, and Lutzomyia sordellii. L. longipalpis, the main vector of Leishmania infantum in Brazil, was the most frequent species, accounting for 76.9% of the total, followed by L. lenti with 8.3%, this species is not a proven vector. Green and urban areas had different sand flies species composition, whereas the high abundance of L. longipalpis in urban areas and the presence of various vector species in both green and urban areas were also observed. Our data point out to the requirement of control measures against phlebotomine sand flies in the municipality of Divinópolis and adoption of strategies aiming entomological surveillance.

  12. Application of Flumethrin Pour-On on Reservoir Dogs and Its Efficacy against Sand Flies in Endemic Focus of Visceral Leishmaniasis, Meshkinshahr, Iran

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    MohammadReza Jalilnavaz

    2015-10-01

    Full Text Available Background: Visceral leishmaniasis (VL is one of the most important parasitic zoonotic diseases in the world. Do­mestic dogs are the main domestic reservoirs of VL in endemic foci of Iran. Various methods, including vaccination, treatment of dogs, detection and removal of infected dogs have different results around the world. General policy on control of canine visceral leishmaniasis is protection of them from sand fly bites. The aim of this study was evalua­tion of pour-on application of flumethrin on dogs against blood-feeding and mortality of field-caught sand flies.Methods: Once every 20 days from May untill September 2013, the treated and control dogs were exposed with field caught sandflies for 2 hours under bed net traps. After the exposure time, both alive and dead sand flies were trans­ferred in netted cups to the laboratory. The mortality rate of them was assessed after 24 hours. The blood-fed or un­fed conditions were determined 2 hours after exposure to the dogs under stereomicroscope.Results: The blood feeding index was varied from 12.0 to 25.0 % and 53.0 to 58.0 % for treated and control dogs respectively (P< 0.0001. The blood feeding inhibition was 75.0–87.0 % and 41.0–46.0 % for the control and treated dogs (P< 0.0001, respectively.The total mortality rate was 94.0–100 % and 19.0–58.0 % respectively for the treated and control groups (P< 0.001.Conclustion: Application of pour-on flumethrin on dogs caused 90–100 % mortality until 2.5 month and inhibited the blood-feeding of sand flies

  13. The sand fly fauna (Diptera: Psychodidae: Phlebotominae) of a focus of cutaneous leishmaniasis in Ilhéus, state of Bahia, Brazil

    OpenAIRE

    Alfredo CR de Azevedo; Maurício L. Vilela; Nataly A Souza; Claudia A Andrade-Coelho; Barbosa,André F; Antônio LS Firmo; Elizabeth F. Rangel

    1996-01-01

    The municipality of Ilhéus, State of Bahia, has a focus of cutaneous leishmaniasis where entomological studies were carried out to determine the sand fly species and their habits. Lutzomyia migonei, L. sallesi, L. tupynambai, L. schreiberi, L. intermedia, L. whitmani, L. yuilli yuilli, L. fischeri, L. pessoai, L. shannoni and L. misionensis were identified. Lutzomyia whitmani was the predominant species. Specimens were collected indoors, at peridomestic sites, in the cocoa plantations and in ...

  14. Breeding sites of phlebotomine sand flies (Diptera: Psychodidae) and efficiency of extraction techniques for immature stages in terra-firme forest in Amazonas State, Brazil.

    Science.gov (United States)

    Alencar, Ronildo Baiatone; de Queiroz, Raul Guerra; Barrett, Toby Vincent

    2011-06-01

    Information on natural breeding sites of phlebotomine sand flies is scanty, due to the difficulties of isolation of immatures from the soil where they occur. The present study investigated breeding sites in several microhabitats in a "terra-firme" forest in Pitinga, Amazonas State, Brazil. Results on the efficacy of different extraction techniques used for isolating sand flies, and the temperature and the pH of the samples collected, are presented. Samples of soil and organic matter from different microhabitats, processed by floatation-sieving, direct examination, Berlese-Tullgren, and emergence cages, revealed, for the first time in Amazonas, breeding sites in five microhabitats (tree bases, unsheltered forest floor, soil from under fallen logs, soil from under roots, and palm-tree bases). Overall, 138 immatures and 29 newly emerged adults were recovered from these microhabitats. The abundance of immatures in samples close to tree bases was significantly higher than in more open sites not adjacent to tree bases. Floatation-sieving and direct examination were the most effective techniques for immature extraction and survival, respectively. Eleven species of the genus Lutzomyia s.l. were identified, with Lutzomyia monstruosa (Floch & Abonnenc) and Lutzomyia georgii Freitas & Barrett being the most abundant. Differences in the specific composition and relative abundance of the immature and adult sand flies on tree bases suggest that breeding sites may be distant from resting or aggregation sites of adults. The pH, which revealed a slightly acidic soil, as well as the temperature, did not show any significant correlation with the number of immature sand flies collected.

  15. Orientation of colonized sand flies Phlebotomus papatasi, P. duboscqi, and Lutzomyia longipalpis (Diptera: Psychodidae) to diverse honeys using a 3-chamber in-line olfactometer.

    Science.gov (United States)

    Wasserberg, G; Kirsch, P; Rowton, E D

    2014-06-01

    A 3-chamber in-line olfactometer designed for use with sand flies is described and tested as a high-throughput method to screen honeys for attractiveness to Phlebotomus papatasi (four geographic isolates), P. duboscqi (two geographic isolates), and Lutzomyia longipalpis maintained in colonies at the Walter Reed Army Institute of Research. A diversity of unifloral honey odors were evaluated as a proxy for the natural floral odors that sand flies may use in orientation to floral sugar sources in the field. In the 3-chamber in-line olfactometer, the choice modules come directly off both sides of the release area instead of angling away as in the Y-tube olfactometer. Of the 25 honeys tested, five had a significant attraction for one or more of the sand fly isolates tested. This olfactometer and high-throughput method has utility for evaluating a diversity of natural materials with unknown complex odor blends that can then be down-selected for further evaluation in wind tunnels and/or field scenarios.

  16. Environmental Niche Modelling of Phlebotomine Sand Flies and Cutaneous Leishmaniasis Identifies Lutzomyia intermedia as the Main Vector Species in Southeastern Brazil

    Science.gov (United States)

    Meneguzzi, Viviane Coutinho; dos Santos, Claudiney Biral; Leite, Gustavo Rocha; Fux, Blima; Falqueto, Aloísio

    2016-01-01

    Cutaneous leishmaniasis (CL) is caused by a protozoan of the genus Leishmania and is transmitted by sand flies. The state of Espírito Santo (ES), an endemic area in southeast Brazil, has shown a considerably high prevalence in recent decades. Environmental niche modelling (ENM) is a useful tool for predicting potential disease risk. In this study, ENM was applied to sand fly species and CL cases in ES to identify the principal vector and risk areas of the disease. Sand flies were collected in 466 rural localities between 1997 and 2013 using active and passive capture. Insects were identified to the species level, and the localities were georeferenced. Twenty-one bioclimatic variables were selected from WorldClim. Maxent was used to construct models projecting the potential distribution for five Lutzomyia species and CL cases. ENMTools was used to overlap the species and the CL case models. The Kruskal–Wallis test was performed, adopting a 5% significance level. Approximately 250,000 specimens were captured, belonging to 43 species. The area under the curve (AUC) was considered acceptable for all models. The slope was considered relevant to the construction of the models for all the species identified. The overlay test identified Lutzomyia intermedia as the main vector of CL in southeast Brazil. ENM tools enable an analysis of the association among environmental variables, vector distributions and CL cases, which can be used to support epidemiologic and entomological vigilance actions to control the expansion of CL in vulnerable areas. PMID:27783641

  17. [Leishmania major Yakimoff et Schokhor, 1914 (Kinetoplastida: Trypanosomatidae) in Meriones shawi Duvernoy, 1842 (Rodentia: Gerbillidae): persistence of the infection in meriones and its infectivity for the sand fly vector (Phlebotomus) papatasi Scopoli, 1786 (Diptera: Psychodidae).

    OpenAIRE

    Derbali, M.; Chelbi, I.; Ben Hadj Ahmed, S.; Zhioua, E.

    2012-01-01

    International audience; The ability of the sand fly Phlebotomus papatasi to transmit Leishmania major, the etiologic agent of zoonotic cutaneous leishmaniasis, to Meriones shawi, the natural reservoir host of this parasite, was studied under laboratory conditions. Sand flies became infected with L. major after feeding on a lesion of needle-inoculated M. shawi. Moreover, P. papatasi, previously infected with L. major, transmitted the parasite to M. shawi by bite during a second bloodmeal. Two ...

  18. Efficacy and duration of three residual insecticides on cotton duck and vinyl tent surfaces for control of the sand fly Phlebotomus papatasi (Diptera: Psychodidae).

    Science.gov (United States)

    Zayed, Abdel Baset B; Hoel, David F; Tageldin, Reham A; Fawaz, Emaldeldin Y; Furman, Barry D; Hogsette, Jerome A; Bernier, Ulrich R

    2013-01-01

    This study evaluated the toxicity and duration of 3 residual insecticides against the Old World sand fly, Phlebotomus papatasi, an important vector of cutaneous leishmaniasis, on 2 types of tent material used by the US military in Afghanistan and the Middle East. Vinyl and cotton duck tent surfaces were treated at maximum labeled rates of lambda-cyhalothrin (Demand CS, Zeneca Inc, Wilmington, DE), bifenthrin (Talstar P Professional, FMC Corporation, Philadelphia, PA) and permethrin (Insect Repellent, Clothing Application, 40%), then subsequently stored in indoor, shaded spaces at room temperature (60%-70% relative humidity (RH), 22°C-25°C), and under sunlight and ambient air temperatures outdoors (20%-30% RH, 29°C-44°C). Insecticide susceptible colony flies (F110) obtained from the insectary of US Naval Medical Research Unit No. 3, Cairo, Egypt, were exposed to treated tent surfaces for 30-minute periods twice monthly for up to 5 months, then once monthly thereafter, using the World Health Organization cone assay. Lambda-cyhalothrin treated cotton duck tent material stored indoors killed P. papatasi for 8 months, while the complementary sun-exposed cotton duck material killed adult flies for 1 month before the efficacy dropped to less than 80%. Sand fly mortality on permethrin- and bifenthrin-treated cotton duck decreased below 80% after 2 weeks exposure to sunlight. Shade-stored permethrin and bifenthrin cotton duck material killed more than 80% of test flies through 5 months before mortality rates decreased substantially. Vinyl tent material provided limited control (less than 50% mortality) for less than 1 month with all treatment and storage regimes. Lambda-cyhalothrin-treated cotton duck tent material provided the longest control and produced the highest overall mortalities (100% for 8 months (shaded), more than 90% for 1 month (sunlight-exposed)) of both cotton duck and vinyl tents.

  19. Ecology of phlebotomine sand flies in the rural community of Mont Rolland (Thies region, Senegal: area of transmission of canine leishmaniasis.

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    Massila W Senghor

    Full Text Available BACKGROUND: Different epidemiological studies previously indicated that canine leishmaniasis is present in the region of Thiès (Senegal. However, the risks to human health, the transmission cycle and particularly the implicated vectors are unknown. METHODOLOGY/PRINCIPAL FINDINGS: To improve our knowledge on the population of phlebotomine sand flies and the potential vectors of canine leishmaniasis, sand flies were collected using sticky traps, light traps and indoor spraying method using pyrethroid insecticides in 16 villages of the rural community of Mont Rolland (Thiès region between March and July 2005. The 3788 phlebotomine sand flies we collected (2044 males, 1744 females were distributed among 9 species of which 2 belonged to the genus Phlebotomus: P. duboscqi (vector of cutaneous leishmaniasis in Senegal and P. rodhaini. The other species belonged to the genus Sergentomyia: S. adleri, S. clydei, S. antennata, S. buxtoni, S. dubia, S. schwetzi and S. magna. The number of individuals and the species composition differed according to the type of trap, suggesting variable, species-related degrees of endophily or exophily. The two species of the genus Phlebotomus were markedly under-represented in comparison to the species of the genus Sergentomyia. This study also shows a heterogeneous spatial distribution within the rural community that could be explained by the different ecosystems and particularly the soil characteristics of this community. Finally, the presence of the S. dubia species appeared to be significantly associated with canine leishmaniasis seroprevalence in dogs. CONCLUSIONS/SIGNIFICANCE: Our data allow us to hypothesize that the species of the genus Sergentomyia and particularly the species S. dubia and S. schwetzi might be capable of transmitting canine leishmaniasis. These results challenge the dogma that leishmaniasis is exclusively transmitted by species of the genus Phlebotomus in the Old World. This hypothesis should be

  20. Effect of night time-intervals, height of traps and lunar phases on sand fly collection in a highly endemic area for canine leishmaniasis.

    Science.gov (United States)

    Gaglio, Gabriella; Brianti, Emanuele; Napoli, Ettore; Falsone, Luigi; Dantas-Torres, Filipe; Tarallo, Viviana D; Otranto, Domenico; Giannetto, Salvatore

    2014-05-01

    The activity of phlebotomine sand flies was monitored in a sub-urban area of Sicily in order to acquire data on seasonality and to elucidate the effect of the night time-intervals, height of traps from ground and lunar phases on the abundance of the capture. The study was conducted in the farm of the University of Messina (Italy). Light traps were placed as in the following: biweekly, from dusk to dawn, and from May to November; for three consecutive nights from 18:00 to 6:00, with the net bag being changed every 2h; for 30 days, at different heights from 18:00 to 6:00. A total of five species (i.e., Phlebotomus perniciosus, Phlebotomus neglectus, Phlebotomus sergenti, Phlebotomus perfiliewi, and Sergentomyia minuta), three of which are proven vectors of Leishmania infantum, were captured. The most abundant species was P. perniciosus (73.3%) followed by S. minuta (23.3%). The highest number of phlebotomine sand flies was collected in August and September with a peak of collection recorded in the evening (i.e., from 20:01 to 22.00). The number of phlebotomine sand flies collected at 50cm above the ground was significantly higher (P=0.041) than that captured at 150cm. Results of this study shed light on the ecology of main phlebotomine species in the Mediterranean area, and on the influence of some factors, such as time and height of traps, on the light trap capture efficiency.

  1. Vertical stratification and development aspects of phlebotomine sand flies (Diptera: Psychodidae) in an area of Atlantic Forest tree species in a metropolitan region in northeastern Brazil.

    Science.gov (United States)

    Cortez, A M; Silva, V P M; Queiroz, P V S; Andrade, H T A; Loiola, M I B; Ximenes, M F F M

    2007-12-01

    In the state of Rio Grande do Norte in northeast Brazil, cases of visceral leishmaniasis (VL) occur mainly in the periurban areas of the city of Natal. Lutzomyia longipalpis Lutz & Neiva 1912 (Diptera: Psychodidae), a vector of Leishmania chagasi (Protozoa: Trypanosomatidae) to humans, is found throughout the state. Flora and fauna influence the distribution of sand fly species, whose horizontal or vertical stratification can be used as a parameter for identifying potential vectors, considering the presence of vertebrate hosts in the area. The purpose of this study was to obtain information about the vertical stratification of phlebotomine sand flies in an endemic area of leishmaniasis in Rio Grande do Norte, and associate it with the presence of other animals in the peridomiciliary environment as well as to analyze, under laboratory conditions, aspects of L. longipalpis reproduction in wild females. The sand flies were captured with light traps hung at different heights in species of Atlantic Forest trees and in a peridomiciliary environment in animal shelters. The traps were placed between 17:30 and 6:00 of the following day, in a peridomiciliary and extradomiciliary area of a forest fragment in both dry and rainy months. In the extradomiciliary environment, the traps were installed at 1, 3 and 5 m above the ground. The biological cycle of L. longipalpis was followed from the eggs of 200 wild females. Specimens of L. lenti, L. walkeri, and L. migonei were captured. The comparison and statistical analysis showed that L. longipalpis is more abundant at a height of 3 m and L. evandroi at 1 m. In the animal shelters (chickens, horses, and armadillos), we captured mainly specimens of L. longipalpis and L. evandroi. The duration of the biological cycle of L. longipalpis was approximately 38 days at a temperature of 28 degrees C.

  2. IMPROVING MASS REARING TECHNOLOGY FOR SOUTH AMERICAN FRUIT FLY (DIPTERA:TEPHRITIDAE

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    Raimundo Braga Sobrinho

    2006-01-01

    Full Text Available Studies on availability of suitable and economic diets for adults and larvae of the South American fruit fly Anastrepha fraterculus (Wiedemann, 1830 were carried out at the Entomology Unit of the FAO/IAEA Agriculture and Biotechnology Laboratories in Seibersdorf, Austria with the aim to find the best diets to fit in a large scale mass rearing production. The best diet for adult was the combination of Hydrolysate Corn Protein + Yeast Hydrolysate Enzymatic + Sugar (3:1:3. This diet resulted in the highest numbers of egg/female/day, spermatozoid in the spermathecae, percentages of egg hatch, the lowest mortality rate of adults and the highest average mating duration compared with the standard adult diet based on Yeast Hydrolysate Enzymatic + Sugar (1:3. Among eleven larval diets tested, diets based on sugarcane and sugarbeet bagases plus 7% brewer yeast, 8% sugar, 0.2% sodium benzoate, 0.8% of hydrochloric acid and 60% water (adjusted, yielded the highest percentages of egg hatching, pupal recovery, pupal weight and adult emergence. There was no statistical difference with the standard larval diet based on wheat germ 3%, corncob 15%, corn flower 8%, brewer yeast 6%, sugar 8%, sodium benzoate 0.23%, hydrochloric acid 0.63%, nipagin 0.14% and water 59% (adjusted. The significant performance of these adult and larval diets open discussion for future researches on improvement of rearing techniques required for the establishment of sterile insect technique (SIT program focused on the South American fruit fly.

  3. Feeding preference of the sand flies Lutzomyia umbratilis and L. spathotrichia (diptera: Psychodidae, Phlebotominae in an urban forest patch in the city of Manaus, Amazonas, Brazil

    Directory of Open Access Journals (Sweden)

    Liliane Coelho da Rocha

    2004-10-01

    Full Text Available Precipitin tests were performed on blood meals of 199 sand flies (161 Lutzomyia umbratilis, 34 L. spathotrichia, two Lutzomyia of group shannoni, one L. anduzei in a non-flooded upland forest on the Campus of the Universidade Federal do Amazonas. This is the second largest forest fragment in an urban setting in Brazil. Results on L. umbratilis, which is considered to be the principal leishmaniasis vector in this region, indicated rodents as its predominant blood source in contrast to previous reports in which blood meal analysis indicated that this species fed principally on Xenarthra (particularly sloths

  4. Detection of Leishmania DNA and blood meal sources in phlebotomine sand flies (Diptera: Psychodidae) in western of Spain: Update on distribution and risk factors associated.

    Science.gov (United States)

    Bravo-Barriga, D; Parreira, R; Maia, C; Afonso, M O; Blanco-Ciudad, J; Serrano, F J; Pérez-Martín, J E; Gómez-Gordo, L; Campino, L; Reina, D; Frontera, E

    2016-12-01

    Leishmaniosis caused by Leishmania infantum is present in Mediterranean countries, with high prevalence in areas of the center and south of Spain. However, in some regions such as Extremadura (in southwest of Spain), data has not been updated since 1997. The aim of this work was (i) to provide information about the distribution of phlebotomine sand fly species in western of Spain (Extremadura region), (ii) to determine risk factors for the presence of sand fly vectors and (iii) to detect Leishmania DNA and identify blood meal sources in wild caught females. During 2012-2013, sand flies were surveyed using CDC miniature light-traps in 13 of 20 counties in Extremadura. Specimens were identified morphologically and females were used for molecular detection of Leishmania DNA by kDNA, ITS-1 and cyt-B. In addition, blood meals origins were analyzed by a PCR based in vertebrate cyt b gene. A total of 1083 sand flies of both gender were captured and identified. Five species were collected, Phlebotomus perniciosus (60.76%), Sergentomyia minuta (29.92%), P. ariasi (7.11%), P. papatasi (1.48%) and P. sergenti (0.74%). The last three species constitute the first report in Badajoz, the most southern province of Extremadura region. Leishmania DNA was detected in three out of 435 females (one P. pernicious and two S. minuta). Characterization of obtained DNA sequences by phylogenetic analyses revealed close relatedness with Leishmania tarentolae in S. minuta and L. infantum in P. perniciosus. Haematic preferences showed a wide range of hosts, namely: swine, humans, sheep, rabbits, horses, donkeys and turkeys. The simultaneous presence of P. perniciosus and P. ariasi vectors, the analysis of blood meals, together with the detection of L. infantum and in S. minuta of L. tarentolae, confirms the ideal conditions for the transmission of this parasitosis in the western of Spain. These results improve the epidemiological knowledge of leishmaniosis and its vectors in this part of Spain

  5. Serological markers of sand fly exposure to evaluate insecticidal nets against visceral leishmaniasis in India and Nepal: a cluster-randomi trial

    DEFF Research Database (Denmark)

    Gidwani, K; Picado, A; Rijal, S

    2011-01-01

    Background: Visceral leishmaniasis is the world’ second largest vector-borne parasitic killer and a neglected tropical disease, prevalent in poor communities. Long-lasting insecticidal nets (LNs) are a low cost proven vector intervention method for malaria control; however, their effectiveness...... against visceral leishmaniasis (VL) is unknown. This study quantified the effect of LNs on exposure to the sand fly vector of VL in India and Nepal during a two year community intervention trial. Methods: As part of a paired-cluster randomized controlled clinical trial in VL-endemic regions of India...

  6. Horizontal stratification of the sand fly fauna (Diptera: Psychodidae) in a transitional vegetation between caatinga and tropical rain forest, state of Bahia, Brazil.

    Science.gov (United States)

    Dias-Lima, Artur Gomes; Guedes, Maria Lenise Silva; Sherlock, Italo A

    2003-09-01

    A study about the horizontal stratification of the sand fly fauna in two distinct ecosystems, caatinga area, endemic for visceral leishmaniasis, and the tropical rain forest area, endemic for cutaneous leishmaniasis, was performed in the state of Bahia, Brazil. Lutzomyia longipalpis was predominant in the caatinga, and following it came the species L. capixaba and L. oswaldoi. In the tropical rain forest other species were found, such as L. intermedia, L. migonei, L. whitmani, L. yuilli, L.fischeri, L. damascenoi, L. evandroi, L. monticola, and L. lenti. It was found that the geographical limits of the vector species of visceral and cutaneous leishmaniasis are clearly defined by the biological and phytogeographic characteristics.

  7. The sand fly fauna (Diptera: Psychodidae: Phlebotominae) of a focus of cutaneous leishmaniasis in Ilhéus, State of Bahia, Brazil.

    Science.gov (United States)

    Azevedo, A C; Vilela, M L; Souza, N A; Andrade-Coelho, C A; Barbosa, A F; Firmo, A L; Rangel, E F

    1996-01-01

    The municipality of Ilhéus, State of Bahia, has a focus of cutaneous leishmaniasis where entomological studies were carried out to determine the sand fly species and their habits. Lutzomyia migonei, L. sallesi, L. tupynambai, L. schreiberi, L. intermedia, L. whitmani, L. yuilli yuilli, L. fischeri, L. pessoai, L. shannoni and L. misionensis were identified. Lutzomyia whitmani was the predominant species. Specimens were collected indoors, at peridomestic sites, in the cocoa plantations and in other types of collections. Females fed readily on humans and were attracted to domestic animals. Our evidence suggests that L. whitmani is a probable vector.

  8. The sand fly fauna (Diptera: Psychodidae: Phlebotominae of a focus of cutaneous leishmaniasis in Ilhéus, state of Bahia, Brazil

    Directory of Open Access Journals (Sweden)

    Alfredo CR Azevedo

    1996-02-01

    Full Text Available The municipality of Ilhéus, State of Bahia, has a focus of cutaneous leishmaniasis where entomological studies were carried out to determine the sand fly species and their habits. Lutzomyia migonei, L. sallesi, L. tupynambai, L. schreiberi, L. intermedia, L. whitmani, L. yuilli yuilli, L. fischeri, L. pessoai, L. shannoni and L. misionensis were identified. Lutzomyia whitmani was the predominant species. Specimens were collected indoors, at peridomestic sites, in the cocoa plantations and in other types of collections. Females fed readily on humans and were attracted to domestic animals. Our evidence suggests that L. whitmani is a probable vector.

  9. Laboratory Evaluation of Diflubenzuron as a Feed-Through for Control of Immature Sand Flies (Diptera: Psychodidae)

    Science.gov (United States)

    2007-03-01

    Phlebotomine sand ßies are the vectors of the proto- zoan parasites that cause leishmaniasis. Sand ßies also are vectors of the disease agents Bartonella ...terrestrial larvae of several species of Diptera, including house ßies, Musca domestica L.; face ßies, Musca autumnalis De Geer; stable ßies, Stomoxys cal

  10. North American Oil Sands: History of Development, Prospects for the Future

    Science.gov (United States)

    2008-01-17

    mixture of sand, bitumen (a heavy crude that does not flow naturally), and water, can be mined or the oil can be extracted in-situ using thermal recovery...quartz sand, bitumen , and water that can either be mined or extracted in-situ5 using thermal recovery techniques. Typically, oil sands contain about...different technology for bitumen extraction than that used for Alberta’s water-wetted deposits. Oil sands are characterized as having a wet interface

  11. New Insights Into the Transmissibility of Leishmania infantum From Dogs to Sand Flies: Experimental Vector-Transmission Reveals Persistent Parasite Depots at Bite Sites

    Science.gov (United States)

    Aslan, Hamide; Oliveira, Fabiano; Meneses, Claudio; Castrovinci, Philip; Gomes, Regis; Teixeira, Clarissa; Derenge, Candace A.; Orandle, Marlene; Gradoni, Luigi; Oliva, Gaetano; Fischer, Laurent; Valenzuela, Jesus G.; Kamhawi, Shaden

    2016-01-01

    Canine leishmaniasis (CanL) is a chronic fatal disease of dogs and a major source of human infection through propagation of parasites in vectors. Here, we infected 8 beagles through multiple experimental vector transmissions with Leishmania infantum–infected Lutzomyia longipalpis. CanL clinical signs varied, although live parasites were recovered from all dog spleens. Splenic parasite burdens correlated positively with Leishmania-specific interleukin 10 levels, negatively with Leishmania-specific interferon γ and interleukin 2 levels, and negatively with Leishmania skin test reactivity. A key finding was parasite persistence for 6 months in lesions observed at the bite sites in all dogs. These recrudesced following a second transmission performed at a distal site. Notably, sand flies efficiently acquired parasites after feeding on lesions at the primary bite site. In this study, controlled vector transmissions identify a potentially unappreciated role for skin at infectious bite sites in dogs with CanL, providing a new perspective regarding the mechanism of Leishmania transmissibility to vector sand flies. PMID:26768257

  12. Experimental effect of feeding on Ricinus communis and Bougainvillea glabra on the development of the sand fly Phlebotomus papatasi (Diptera: Psychodidae) from Egypt.

    Science.gov (United States)

    Kaldas, Rania M; El Shafey, Azza S; Shehata, Magdi G; Samy, Abdallah M; Villinski, Jeffrey T

    2014-04-01

    Plants are promising sources of agents useful for the control of vectors of human diseases including leishmaniasis. The effect of Ricinus communis (Euphorbiaceae) and Bougainvillea glabra (Nyctaginaceae), on transmission of leishmaniasis was investigated using them as diets for Phlebotomus papatasi to monitor their effect on life-history traits. P. papatasi were allowed to feed separately on both plants then offered a blood-meal. Fed-females were observed daily for egg-laying and subsequent developmental stages. P. papatasi was able to feed on B. glabra (29.41% females and 46.30% males) and R. communis (5.80% females and 10.43% males). 34.28% of females died within 24-48 hours post-feeding on R. communis, whereas, it was 16.5% in females fed on B. glabra. Overall fecundity of surviving females was reduced compared to controls, reared on standard laboratory diet; however there was no effect on the sex ratio of progeny. Female P. papatasi in the control group had significantly longer life span compared to plant-fed group. Feeding on these plants not only decreased sand fly survival rates but incurred negative effects on fecundity. Findings indicate that planting high densities of R. communis and B. glabra in sand flies-endemic areas will reduce population sizes and reduce the risk of Leishmania major infections.

  13. Monthly Distribution of Phlebotomine Sand Flies, and Biotic and Abiotic Factors Related to Their Abundance, in an Urban Area to Which Visceral Leishmaniasis Is Endemic in Corumbá, Brazil

    Science.gov (United States)

    Casaril, Aline Etelvina; Fernandes, Wagner Souza; Ravanelli, Michelle de Saboya; Paranhos Filho, Antônio Conceição; Oshiro, Elisa Teruya; de Oliveira, Alessandra Gutierrez

    2016-01-01

    The monthly distribution and abundance of sand flies are influenced by both biotic and abiotic factors. The present study aimed to evaluate the seasonal distribution of sand flies and the relation between their abundance and environmental parameters, including vegetation and climate. This study was conducted over a 2-year period (April 2012 to March 2014). Monthly distribution was evaluated through the weekly deployment of CDC light traps in the peridomicile area of 5 residences in an urban area of the municipality of Corumbá in the State of Mato Grosso do Sul, Brazil. Meteorological data were obtained from the Mato Grosso do Sul Center for Weather, Climate, and Water Resources. The spectral indices were calculated based on spatial resolution images (GeoEye) and the percentage of vegetal coverage. Differences in the abundance of sand flies among the collection sites were assessed using the Kruskal-Wallis test, and the strength of correlations between environmental variables was determined by calculating Spearman’s correlation coefficients. Lutzomyia cruzi, Lu. forattinii, and Evandromyia corumbaensis were the most frequently found species. Although no significant association was found among these sand fly species and the tested environmental variables (vegetation and climate), high population peaks were found during the rainy season, whereas low peaks were observed in the dry season. The monthly distribution of sand flies was primarily determined by Lu. cruzi, which accounted for 93.94% of the specimens collected each month throughout the experimental period. The fact that sand flies were detected year-round indicates a continuous risk of infection to humans, demonstrating the need for targeted management and education programs. PMID:27783667

  14. Comparative Field Evaluation of Different Traps for Collecting Adult Phlebotomine Sand Flies (Diptera: Psychodidae) in an Endemic Area of Cutaneous Leishmaniasis in Quintana Roo, Mexico.

    Science.gov (United States)

    Rodríguez-Rojas, Jorge J; Arque-Chunga, Wilfredo; Fernández-Salas, Ildefonso; Rebollar-Téllez, Eduardo A

    2016-06-01

    Phlebotominae are the vectors of Leishmania parasites. It is important to have available surveillance and collection methods for the sand fly vectors. The objectives of the present study were to evaluate and compare traps for the collection of sand fly species and to analyze trap catches along months and transects. Field evaluations over a year were conducted in an endemic area of leishmaniasis in the state of Quintana Roo, Mexico. A randomized-block design was implemented in study area with tropical rainforest vegetation. The study design utilized 4 transects with 11 trap types: 1) Centers for Disease Control and Prevention (CDC) light trap with incandescent bulb (CDC-I), 2) CDC light trap with blue light-emitting diodes (LEDs) (CDC-B), 3) CDC light trap with white LEDs (CDC-W), 4) CDC light trap with red LEDs (CDC-R), 5) CDC light trap with green LEDs (CDC-G), 6) Disney trap, 7) Disney trap with white LEDs, 8) sticky panels, 9) sticky panels with white LEDs, 10) delta-like trap, and 11) delta-like trap with white LEDs. A total of 1,014 specimens of 13 species and 2 genera (Lutzomyia and Brumptomyia) were collected. There were significant differences in the mean number of sand flies caught with the 11 traps; CDC-I was (P  =  0.0000) more effective than the other traps. Other traps exhibited the following results: CDC-W (17.46%), CDC-B (15.68%), CDC-G (14.89%), and CDC-R (14.30%). The relative abundance of different species varied according to trap types used, and the CDC-I trap attracted more specimens of the known vectors of Leishmania spp., such as like Lutzomyia cruciata, Lu. shannoni, and Lu. ovallesi. Disney trap captured more specimens of Lu. olmeca olmeca. Based on abundance and number of species, CDC light traps and Disney traps appeared to be good candidates for use in vector surveillance programs in this endemic area of Mexico.

  15. [Occurrence of sand flies (Diptera, Psychodidae) in leishmaniasis foci in an ecotourism area around the Lençóis Maranhenses National Park, Brazil].

    Science.gov (United States)

    Rebêlo, José Manuel Macário; Assunção Júnior, Antonildes Nascimento; Silva, Orleans; Moraes, Jorge Luiz Pinto

    2010-01-01

    The distribution and relative abundance of sand fly species were studied in the municipality of Barreirinhas, Maranhão State, Brazil, around the Lençóis Maranhenses National Park, from January to June 2005, August 2004, July 2005, and September/2008. A total of 6,658 specimens were captured. The most frequent species were Lutzomyia whitmani (46.6%), L. longipalpis (29.9%), L. evandroi (17.1%), and L. lenti (4.8%), while L. termitophila, L. flaviscutellata, L. migonei, L. infraspinosa, L. sordellii, L. wellcomei, L. antunesi, and L. trinidadensis represented 1.6%. The presence of Leishmania vector species explains the high detection rate for tegumentary leishmaniasis in 2000 (308.2), 2001 (310.9), 2002 (338.2), and 2005 (313.6) and active foci of human visceral leishmaniasis in the municipality of Barreirinhas.

  16. External morphology of sensory structures of fourth instar larvae of neotropical species of phlebotomine sand flies (Diptera: Psychodidae under scanning electron microscopy

    Directory of Open Access Journals (Sweden)

    Pessoa Felipe Arley Costa

    2001-01-01

    Full Text Available In the present study, some morphological structures of antennae, maxillary palps and caudal setae of fourth instar larvae of laboratory-reared phlebotomine sand flies (Lutzomyia longipalpis, L. migonei, L. evandroi, L. lenti, L. sericea, L. whitmani and L. intermedia of the State of Ceará, Brazil, were examined under scanning electron microscopy. The antennal structures exhibited considerable variation in the morphology and position. A prominent digitiform distal segment has been observed only on the antenna of species of the subgenus Nyssomyia. The taxonomic relevance of this and other antennal structure is discussed. The papiliform structures found in the maxillae and the porous structures of the caudal setae of all species examined may have chemosensory function. Further studies with transmission electron microscopy are needed to better understand the physiological function of these external structures.

  17. Correlation of male genital filaments and female spermathecal ducts in New World sand flies of the Lutzomyia intermedia species complex (Diptera: Psychodidae, Phlebotominae

    Directory of Open Access Journals (Sweden)

    Marcondes Carlos Brisola

    2003-01-01

    Full Text Available The lengths of the male genital filaments and female spermathecal ducts were measured in phlebotomine sand flies of the Lutzomyia intermedia species complex and the ratios between these characters calculated. Ratios for L. intermedia s. s. from Northeast vs Southeast Brazil (Espírito Santo and Minas Gerais, Espírito Santo/Minas Gerais vs Rio de Janeiro/São Paulo and L. intermedia vs L. neivai were significantly different at P < 0.1, 0.05 and 0.01 respectively when compared using ANOVA. The spermathecal ducts and genital filaments of L. intermedia were significantly longer than those of L. neivai (P < 0.01 and could be used to differentiate these species. The taxonomic and biological significance of these differences is discussed.

  18. The Development of Leishmania tropica in Sand Flies (Diptera: Psychodidae): A Comparison of Colonies Differing in Geographical Origin and a Gregarine Coinfection.

    Science.gov (United States)

    Jancarova, Magdalena; Hlavacova, Jana; Volf, Petr

    2015-11-01

    Phlebotomus sergenti Parrot, 1917 is the main vector of Leishmania tropica; however, its broad geographical range and molecular heterogeneity suggest possible variability in vector competence. We infected laboratory-reared P. sergenti originating from Turkey and Israel to compare their susceptibility to L. tropica. In both tested groups, heavy late-stage infections with the presence of metacyclic forms and colonization of the stomodeal valve were observed. The similar development of Leishmania in both sand fly colonies indicates that the different geographical origin of P. sergenti is not reflected by a different vector competence to L. tropica. Additionally, we tested the effect of the gregarine Psychodiella sergenti on L. tropica coinfections; no apparent differences were found between P. sergenti infected or not infected by gregarines.

  19. Notes on the phlebotomine sand flies from the Peruvian southeast--I. Description of Lutzomyia (Helcocyrtomyia) adamsi n. sp. (Diptera: Psychodidae).

    Science.gov (United States)

    Fernandez, R; Galati, E B; Carbajal, F; Wooster, M T; Watts, D M

    1998-01-01

    A new species of phlebotomine sand fly, Lutzomyia adamsi n. sp., is described and illustrated from specimens collected during August 1994, in Sandia, Department of Puno-Peru. According to the Oficina Nacional de Evaluacion de Recursos Naturales(ONERN 1976), this locality is situated in the life zone known as humid, mountain, low tropical forest (bh-MBT). Many areas in the northern part of Puno, mainly in the Inambari and Tambopata basins, are endemic to leishmaniasis. These areas are the continuation of others, largely known as "leishmaniasic" in the departments of Cusco and Madre de Dios. The morphological characteristics indicated that this species belongs to the genus Lutzomyia, subgenus Helcocyrtomyia Barretto, 1962.

  20. Horizontal stratification of the sand fly fauna (Diptera: Psychodidae in a transitional vegetation between caatinga and tropical rain forest, state of Bahia, Brazil

    Directory of Open Access Journals (Sweden)

    Dias-Lima Artur Gomes

    2003-01-01

    Full Text Available A study about the horizontal stratification of the sand fly fauna in two distinct ecosystems, caatinga area, endemic for visceral leishmaniasis, and the tropical rain forest area, endemic for cutaneous leishmaniasis, was performed in the state of Bahia, Brazil. Lutzomyia longipalpis was predominant in the caatinga, and following it came the species L. capixaba and L. oswaldoi. In the tropical rain forest other species were found, such as L. intermedia, L. migonei, L. whitmani, L. yuilli, L.fischeri, L. damascenoi, L. evandroi, L. monticola, and L. lenti. It was found that the geographical limits of the vector species of visceral and cutaneous leishmaniasis are clearly defined by the biological and phytogeographic characteristics.

  1. Evidence for community structure and habitat partitioning in coastal dune stiletto flies at the Guadalupe-Nipomo dunes system, California

    OpenAIRE

    Holston, Kevin C.

    2005-01-01

    This study provides empirical evidence for habitat selection by North American species of stiletto flies (Diptera: Therevidae), based on local distributions of adults and immatures, and the first hypothesis of community assemblages proposed for a stiletto fly community. Sites at three localities within the Guadalupe-Nipomo dune system were sampled for stiletto flies in 1997 and 2001 by sifting sand, malaise trapping, and hand netting. Nine species were collected from four ecological zones and...

  2. Flebotomíneos de Timóteo, Estado de Minas Gerais, Brasil (Diptera: Psychodidae Sand flies in Timóteo, Minas Gerais, Brazil (Diptera: Psychodidae

    Directory of Open Access Journals (Sweden)

    José Dilermando Andrade Filho

    1997-10-01

    Full Text Available Casos esporádicos de leishmaniose tegumentar têm ocorrido no Município de Timóteo, Minas Gerais, basicamente na população rural. Para conhecer a fauna de flebotomíneos da região, foram instaladas sete armadilhas luminosas de New Jersey na cidade, em sete diferentes bairros. As coletas foram realizadas no período de junho a outubro de 1994, dezembro de 1994 e janeiro a março de 1995, com um total de 3.240 horas por armadilha. Foram capturados 4.396 flebotomíneos, distribuídos em dois gêneros e vinte espécies: Brumptomyia cunhai, Brumptomyia nitzulescui, Lutzomyia (Nyssomyia whitmani, Lutzomyia (Nyssomyia intermedia, Lutzomyia quinquefer, Lutzomyia lenti, Lutzomyia (Pintomyia fischeri, Lutzomyia migonei, Lutzomyia sallesi, Lutzomyia termitophila, Lutzomyia aragaoi, Lutzomyia borgmeieri, Lutzomyia (Psathyromyia lutziana, Lutzomyia (Sciopemyia sordellii, Lutzomyia (Pintomyia pessoai, Lutzomyia (Trichopygomyia longispina, Lutzomyia misionensis, Lutzomyia (Psychodopygus davisi, Lutzomyia lanei, Lutzomyia (Pressatia sp. A espécie L. (N. whitmani foi a mais freqüente com 52,12%, seguida de L. (N. intermedia com 34,10%, e ambas podem estar participando da transmissão de leishmaniose cutânea na região.Sporadic cases of tegumentary leishmaniasis have occurred in Timóteo, Minas Gerais State, basically among the rural population. In order to study the region's sand fly population, New Jersey light traps were set in seven different neighborhoods. Specimens were gathered from June through October 1994, December 1994, and January through March 1995, with a total of 3,240 hours per trap. A total of 4,396 sand flies were captured, distributed among two genera and twenty species: Brumptomyia cunhai, Brumptomyia nitzulescui, Lutzomyia (Nyssomyia whitmani, Lutzomyia (Nyssomyia intermedia, Lutzomyia quinquefer, Lutzomyia lenti, Lutzomyia (Pintomyia fischeri, Lutzomyia migonei, Lutzomyia sallesi, Lutzomyia termitophila, Lutzomyia aragaoi, Lutzomyia

  3. Influence of fly ash and desert Sand content on the compressive strength of high strength concrete%掺粉煤灰、沙漠砂高强混凝土抗压强度研究

    Institute of Scientific and Technical Information of China (English)

    陈云龙; 马菊荣; 刘海峰; 宋建夏

    2014-01-01

    The orthogonal experiment was designed to analyze the influence of water-binder ratio,fly ash content,sand ratio and desert sand replacement ratio on the compressive strength of high strength concrete at the different age.The optimum mix ratio of desert sand high-strength concrete was also given out.Experimental result showed that it is practical to use the desert sand from Mu Us desert sand to mix high strength concrete,the optimum mix ratio of which was that water-binder ratio,fly ash dosage,sand ratio and desert sand replace-ment ratio were 0.24,10%,30% and 30%,respectively.%通过正交试验,分析了水胶比、粉煤灰掺量、砂率、沙漠砂取代率对不同龄期高强混凝土抗压强度影响,并给出了配制高强混凝土的最优配合比。研究结果表明:用沙漠砂替代中砂配制高强混凝土是可行的;综合考虑各阶段的抗压强度,高强混凝土的最优配合比为水胶比0.24、粉煤灰掺量10%、砂率30%、沙漠砂取代率30%。

  4. Intradomiciliary and peridomiciliary captures of sand flies (Diptera: Psychodidae) in the leishmaniasis endemic area of Chapare province, tropic of Cochabamba, Bolivia.

    Science.gov (United States)

    Ballart, C; Vidal, G; Picado, A; Cortez, M R; Torrico, F; Torrico, M C; Godoy, R E; Lozano, D; Gállego, M

    2016-02-01

    In South America, cutaneous leishmaniasis is the most frequent clinical form of leishmaniasis. Bolivia is one of the countries with higher incidence, with 33 cases per 100,000 individuals, and the disease is endemic in 70% of the territory. In the last decade, the number of cases has increased, the age range has expanded, affecting children under 5 years old, and a similar frequency between men and women is found. An entomological study with CDC light traps was conducted in three localities (Chipiriri, Santa Elena and Pedro Domingo Murillo) of the municipality of Villa Tunari, one of the main towns in the Chapare province (Department of Cochabamba, Bolivia). A total of 16 specimens belonging to 6 species of the genus Lutzomyia were captured: Lu. aragaoi, Lu. andersoni, Lu. antunesi, Lu. shawi, Lu. yuilli yuilli and Lu. auraensis. Our results showed the presence of two incriminated vectors of leishmaniasis in an urbanized area and in the intradomicile. More entomological studies are required in the Chapare province to confirm the role of vector sand flies, the intradomiciliary transmission of the disease and the presence of autochthonous cases of cutaneous leishmaniasis.

  5. Influence of fly ash dosage and desert sand replacement ratio on the mechanical properties of desert sand concrete%粉煤灰掺量和沙漠砂替代率对沙漠砂混凝土力学性能影响

    Institute of Scientific and Technical Information of China (English)

    付杰; 马菊荣; 刘海峰

    2015-01-01

    为了研究粉煤灰掺量和沙漠砂替代率对沙漠砂混凝土力学性能影响,进行不同粉煤灰掺量和沙漠砂替代率的沙漠砂混凝土28 d抗压强度和28 d劈裂拉伸强度试验研究,分析粉煤灰掺量和沙漠砂替代率对沙漠砂混凝土28 d的抗压强度和劈裂拉伸强度的影响规律。实验结果表明:随着沙漠砂替代率增加,沙漠砂混凝土抗压强度和劈裂拉伸强度均呈现先增大后减小趋势,沙漠砂替代率为20%时,沙漠砂混凝土抗压强度和劈裂拉伸强度均达到最大值;随着粉煤灰掺量增加,沙漠砂混凝土抗压强度和劈裂拉伸强度先增大后减小,粉煤灰掺量为10%时,沙漠砂混凝土抗压强度和劈裂拉伸强度达到最大值。试验结果可为沙漠砂在工程中的应用提供指导和借鉴。%In order to study the influence of fly ash dosage and desert sand replacement ratio on the mechanical properties of desert sand concrete, experiments on the 28 d compressive strength and splitting tensile strength of desert sand concrete with different fly ash dosage and desert sand replace-ment ratio were conducted. The influence of fly ash dosage and desert sand replacement ratio on the 28 d compressive strength and splitting tensile strength of desert sand concrete was analyzed. Experi-ment results show that with the increase of desert sand replacement ratio, the 28 d compressive strength and splitting tensile strength of desert sand concrete increase first and then decline. When desert sand replacement ratio amounts to 20%, the 28 d compressive strength and splitting tensile strength of desert sand concrete reaches the maximum. With the enhancement of fly ash dosage, the 28 d compressive strength and splitting tensile strength of desert sand concrete also increase first and then decline. When fly ash dosage amounts to 10%, the 28 d compressive strength and splitting ten-sile strength of desert sand concrete reaches the maximum

  6. Molten salt reactors and the oil sands: odd couple or key to north american energy independence?

    Energy Technology Data Exchange (ETDEWEB)

    LeBlanc, D., E-mail: d_leblanc@rogers.com [Ottawa Valley Research Associates Ltd., Ottawa, Ontario (Canada); Quesada, M.; Popoff, C.; Way, D. [Penumbra Energy, Calgary, Alberta (Canada)

    2012-07-01

    The use of nuclear power to aid oil sands development has often been proposed largely due to the virtual elimination of natural gas use and thus a large reduction in GHG emissions. Nuclear power can replace natural gas for process steam production (SAGD) and electricity generation but also potentially for hydrogen production to upgrade bitumen for pipeline transit, synthetic crude production and even at the final refinery stage. Prior candidates included CANDU and gas cooled Pebble Bed Reactors. The case for CANDU use can be shown to be marginally economic with a proven technology but with an uncertainty of current construction costs and too large a unit size (~2400 MWth). PBRs offered modest theoretical cost savings, smaller unit size and the ability to offer higher temperatures needed for thermochemical hydrogen production from water. Interest in PBRs however has greatly waned with the cancellation of their major South African development program which highlighted the severe challenges of helium as a coolant and TRISO fuel manufacturing. More recently, Small Modular Reactors based on scaled down light water reactor technology have attracted interest but are unlikely to compete economically outside of niche applications. However, a 'new' reactor option, the Molten Salt Reactor, has been rapidly gaining momentum over the past decade. This 'new' technology was actually developed over 50 years ago as a thorium breeder reactor to compete with the sodium cooled fast breeder reactor (U-Pu cycle). During this time two molten salt test reactors were constructed. A modern version however would likely be a simpler converter design using Low Enriched Uranium but needing only a small fraction the uranium resources of LWRs or CANDUs. Besides resource sustainability, these unique designs offer large potential improvements in the areas of capital costs, safety and nuclear waste. This presentation will explain the unique attributes and advantages of these

  7. Wind tunnel experimental study on sand-fixing effect of fly ash and polyacrylamide%粉煤灰和聚丙烯酰胺固沙效果的风洞试验

    Institute of Scientific and Technical Information of China (English)

    杨凯; 唐泽军; 赵智; 封建章; 郭平; 丁涛

    2012-01-01

    寻找经济高效的固沙措施对于防治风沙危害具有重要意义.该文采用室内风洞试验,研究了不同粉煤灰施用率(10%,20%和30%)的固沙效果及在粉煤灰最佳施用率的基础上不同聚丙烯酰胺(PAM)施用率(0.05%和0.1%)对其的强化作用.试验研究结果表明,沙土施加粉煤灰后起动风速显著提高,施加PAM进一步小幅提高其起动风速;粉煤灰施用率为20%的沙土可以最有效地抵御8m/s净风和风沙流历时10 min的吹蚀;施加粉煤灰的沙土在14 m/s净风和风沙流历时10 min的吹蚀条件下发生中度风蚀,其风蚀率随着粉煤灰施用率的增大而呈逐步降低的趋势;施加粉煤灰和PAM的沙土可以有效地抵御14 m/s风沙流历时30 min的吹蚀;从经济意义上考虑,推荐粉煤灰施用率为20%和PAM施用率为0.05%的用量水平处理用于风蚀防治.%Searching for an effective and economical sand fixation measure has important significance in wind erosion control. Wind tunnel experiments were conducted to study the sand-fixing effect of fly ash at three different application rates (10%, 20% and 30%) and the intensifying action of polyacrylamide (PAM) at two different application rates (0.05% and 0.1%) on it on the basis of the optimum fly ash application rate. The results indicated that fly ash increased the threshold wind speed of the treated soil significantly, which was further increased by PAM slightly. The soil treated with 20% fly ash could most effectively withstand pure wind and sand-carrying wind with a wind speed of 8 m/s for 10 min respectively. Moderate wind erosion occurred after exposure to pure wind and sand-carrying wind with a wind speed of 14 m/s for 10 min respectively, and there was a decline in the wind erosion rate with the increase of fly ash application rate. The soil treated with 20% fly ash and PAM could effectively withstand sand-carrying wind with a wind speed of 14 m/s for 30 min. 20% fly ash

  8. Studies in Phlebotomine Sand Flies.

    Science.gov (United States)

    1982-06-30

    species of Lutzomyia ( Trichophoromyia ) as well as L. ayrozai, an anthropophilic species previously unreported in Ecuador. The specimens were given to...NOTATION 17. COSATI CODES 18. SUBJECT TERMS (Continue on reverse if necessary and identify by block number) FIELD GROUP SUB-GROUP Lutzomyia ...paper describing the previously unknown male of Sergentomyia blossi from Kenya was completed. The eggs of 5 Lutzomyia species were compared with the

  9. Studies of Phlebotomine Sand Flies.

    Science.gov (United States)

    1980-08-31

    World visceral -4- Leishmania , in Oklahoma in dogs (LTC Larry Hendricks, personal comm.), indicates that the successful establishment of an imported...Lainson and Shaw (1968) and Ward et al. (1973, 1977) incriminated Lu. flaviscutellata (Mangabeira)as the vector of Leishmania mexicana amazonensis in...excessive larval mortality caused by fungal growth, improper diet or moisture, disease and/or other factors (Killick-Kendrick, R. 1978. Acta Tropica 35:297

  10. Studies of Phlebotomine Sand Flies.

    Science.gov (United States)

    1981-05-01

    1953, Hils (UF). Panama . 1 e, Santa Clara, Volcan de Chiriqui, tree trunk in coffee plantation, 11-IV-1955, Hartmann (UF). Previous distribution...Soc. Wash. 8:102. -~ Coquillett, D.W. 1907. Discovery of blood-sucking Psychodidae in America. Ent. News 18:101-102. *de Le6n, J.R. 1971. Contribucion ...Fairchild, G.B. and M. Hertig. 1956. Notes on the Phlebotomus of Panama (Diptera: Psychodidae). XII. The group anthophorus, with descriptions of four new

  11. 球铁飞轮的铁型覆砂铸造生产及缺陷防止%Production of Ductile Iron Fly Wheel by Permanent Mold with Coated Sand and its Defects Elimination

    Institute of Scientific and Technical Information of China (English)

    张春明

    2012-01-01

    主要讲述了球铁飞轮的铁型覆砂铸造工艺的基本要求及生产过程控制,并对该生产工艺中可能出现的各种缺陷及其预防措施进行了总结.%The primary technological characteristics of permanent mold coated sand casting ductile iron fly wheel and its process control were described. Meanwhile, the defects possible encountered in production and countermeasures were presented.

  12. Preparation and Performance of Specified Density Concrete of Pottery Sand Made from Fly Ash%粉煤灰陶砂次轻混凝土的制备与性能

    Institute of Scientific and Technical Information of China (English)

    钱伟; 樊传刚; 冉松林; 李家茂; 郭万金

    2012-01-01

    Specified density concrete (SDC) specimens of different fine aggregate composition were prepared with gravel, ordinary sand, and pottery sand made from fly ash. Their mechanical properties and thennal properties were studied. Compared with ordinary aggregate concrete (OAC), when 25% (volume fraction)ordinary sand was replaced by pottery sand as fine aggregate, the compressive strength of SDC is increased and SDC showed ideallight-weight and high-strength characteristics. The above phenomenon is attributed to reasons that the composite fine aggregate particle size matched well, and micro pump maintenance effect ofpottery sand, as well as the pottery surface potentially active substances reacted volcano ash,which reinforced interfacial strength between ceramic sand and cement paste,which made SDC of potteU(volume fraction of 25%) have highest strength in various ages among all as-prepared specimens.Compared with OAC, the thermal conducting coefficient of SDC (volume fraction of 25%) can be decreased by 42%, namely a small amount of replacement of ordinary sand by pottery sand can result in apparent improvement of heat insulation.%用碎石、粉煤灰陶砂和河砂作为混合集料配制不同细集料组成的次轻混凝土试样,研究它们的力学性能和热学性能.与普通混凝土相比,掺人少量粉煤灰陶砂(陶砂体积分数为25%)的次轻混凝土抗压强度得到提高,表现出较为理想的轻质高强特性.上述现象归功于混合细集料中大小颗粒搭配较好,陶砂的微泵内养护效应以及陶砂表面具有潜在活性物质参加火山灰反应,强化了陶砂与水泥石的界面强度,使掺人体积分数为25%陶砂的次轻混凝土在各龄期具有最高的强度.与普通混凝土相比,当次轻混凝土中陶砂体积分数为25%时,其导热系数可降低42%,即掺入适量陶砂可明显提高混凝土的保温隔热性能.

  13. Preferência alimentar sanguínea de flebotomíneos da Amazônia do Maranhão, Brasil Feeding preference of sand flies in the Amazon, Maranhão State, Brazil

    Directory of Open Access Journals (Sweden)

    Yrla Nívea Oliveira-Pereira

    2008-09-01

    Full Text Available O objetivo deste estudo foi determinar as fontes alimentares sanguíneas de flebotomíneos por meio da reação da precipitina, em Buriticupu, na Amazônia maranhense, Brasil, de julho de 2002 a junho de 2004. Foram detectadas reações simples (87,6%, duplas (8% e não reagentes (4,4%. A presença de flebotomíneos alimentados com sangue humano (6,7% e de possíveis reservatórios de Leishmania no peridomicílio ajuda a explicar a ocorrência de casos autóctones de leishmaniose tegumentar no Município de Buriticupu.The objective of this study was to determine the blood feeding sources for sand flies based on the precipitin test in Buriticupu, Amazon Region, Maranhão State, Brazil, from July 2002 to June 2004. Single (87.6% and double (8% reactions and non-reactive samples (4.4% were found. The presence of sand flies fed on human blood (6.7% and blood of animals that are possible peridomiciliary Leishmania reservoirs helps explain the reporting of autochthonous tegumentary leishmaniasis cases in Buriticupu.

  14. Recent observations on the sand fly (Diptera: Psychodidae fauna of the State of Rondônia, Western Amazônia, Brazil: the importance of Psychdopygus davisi as a vector of zoonotic cutaneous leishmaniasis

    Directory of Open Access Journals (Sweden)

    Gil Luis HS

    2003-01-01

    Full Text Available Sand flies were collected in the central region of the state of Rondônia (W 64º30' to 63º00' and S 10º00'to 11º00' using Shannon and CDC light traps from October 1997 to August 2000. A total of 85,850 specimens representing 78 named species were captured. Of these 14 were new records for Rondônia. The proportion of males/females was 1/1.131. Trypanosomatids, that are presently being identified, were detected in 11 species. Leishmania (Viannia naiffi was recorded from Psychodopygus davisi and P. hirsutus. In the present study the dominant species was P. davisi (39.6% followed by Lutzomyia whitmani (13.1%, P. carrerai (11.6%, and P. hirsutus (10.2%. The importance of P. davisi as a vector of zoonotic cutaneous leishmaniasis is discussed.

  15. The Effective Superiority of I Grade Fly Ash and Effects on the Strength of Cement Sand Mortar in Sanxia Engineering%三峡工程用Ⅰ级粉煤灰效应优势及其对水泥砂浆强度贡献

    Institute of Scientific and Technical Information of China (English)

    朱蓓蓉; 张树青; 吴学礼; 黄士元

    2001-01-01

    研究了三峡工程用Ⅰ级粉煤灰效应优势及其对水泥砂浆强度的贡献。结果表明:相比于Ⅱ级粉煤灰,Ⅰ级粉煤灰的火山灰活性未必更高,但Ⅰ级粉煤灰颗粒形态效应上的优势导致了其对水泥砂浆强度产生更明显的影响。%This paper studies the effective superiority of Ⅰ grade fly ash and effects on the strength of cement sand mortar in Sanxia engineering.The results show that compared with Ⅱ grade fly ash,Ⅰ grade fly ash is not certainly good in chemical reactivity,but its  advantage in shape effect is obvious to the strength of cement sand mortar.

  16. Study on Effect of shrinkage Test of steel fiber, rubber powder, fly ash on desert sand Concrete%钢纤维、橡胶粉、粉煤灰对沙漠砂混凝土收缩影响研究

    Institute of Scientific and Technical Information of China (English)

    冯娜

    2015-01-01

    本文利用对比试验的方法,与混凝土强度等性能测定相同的配比,研究了掺钢纤维粉煤灰沙漠砂混凝土(粉煤灰15%+钢纤维1.5%+沙漠砂20%)及掺橡胶粉粉煤灰沙漠砂混凝土(粉煤灰15%+橡胶粉3%+沙漠砂20%)的收缩。钢纤维、粉煤灰的加入对于减小混凝土的干缩值极为有益,尤其是钢纤维掺入以后,对于混凝土早期的干燥收缩值降低效果显著,而从最终干缩综合来看,掺钢纤维粉煤灰沙漠砂混凝土总收缩率最低,60d收缩率较掺橡胶粉粉煤灰沙漠砂混凝土组及基准组分别降低了17.2%和52.6%。%Using the method of comparative tests, and the ratio of performance measurement of the same strength of concrete mixing steel fiber is studied in this desert sand fly ash concrete (fly ash 15% + steel fiber 1.5% + desert sand20%) and desert sand mixing rubber powder fly ash concrete (fly ash 15% + rubber powder 3% + desert sand20% ) of the contract. The addition of steel fiber and fly ash to reduce the drying shrinkage of concrete value is extremely useful, especially steel fiber after incorporation, the drying shrinkage of concrete value to reduce the effect is remarkable, and from the final drying shrinkage together with steel fiber total shrinkage rate lowest desert sand fly ash concrete, 60 d shrinkage of the desert sand mixing rubber powder ash concrete and benchmark group was reduced by 17.2% and 17.2% respectively.

  17. Phlebotominae sand flies associated with a tegumentary leishmaniasis outbreak, Tucumán Province, Argentina Flebotomíneos associados com surto de leishmaniose tegumentar, na Província de Tucumán, Argentina

    Directory of Open Access Journals (Sweden)

    Oscar Daniel Salomón

    2006-08-01

    Full Text Available The distribution of sand flies and cases of tegumentary leishmaniasis in the area surrounding JB Alberd city, and the proximities of Catamarca province were studied, after an increase of reported cases from JB Alberdi, Tucumán province, in 2003. Of 14 confirmed cases, 57% were females and 57% were less than 15 years old, suggesting peridomestic transmission. However, 86% of them lived close to the Marapa river forest gallery and related wooded areas. Over 1,013 sand flies were collected; Lutzomyia neivai (Pinto, 1926 was prevalent at all the sites (92.3%, while Lutzomyia migonei (França, 1920 (6.7% and Lu. cortelezzii (Brèthes, 1923 (1% were also found. The spatial distribution of Lu. neivai overlapped that of the cases, with higher abundance in microfocal hot spots close to the river in stable vegetated habitats or modified habitats with shadow and animal blood sources. The cumulative outcome of anthropic, ecological and climatic factors could have contributed to the onset of the outbreak.Após um aumento nos casos notificados na cidade de JB Alberdi, Provincia de Tucumán, no ano de 2003, foram estudados a distribuição de flebotomíneos e casos de leishmaniose tegumentar nos arredores de JB Alberdi, e na área próxima à Província de Catamarca. De 14 casos confirmados, 57% foram mulheres e 57% tinham menos de 15 anos de idade, sugerindo transmissão peridomiciliar. Contudo, 86% dos casos residiam perto da galeria florestal do rio Marapa e perto de ilhas de vegetacão residual. De 1.013 flebotomíneos coletados, Lutzomyia neivai (Pinto, 1926 foi a espécie dominante em todos os sítios (92,3%. Também, se capturaram Lutzomyia migonei (França, 1920 (6,7% e Lutzomyia cortelezzii (Brèthes, 1923 (1%. A distribuicão espacial de Lu. neivai se sobrepõe com a dos casos com alta abundância em pontos quentes microfocais próximos ao rio, em habitats estáveis com vegetação, ou habitats modificados com sombras e fonte de sangue animal. O

  18. "A Fly in the Ointment": African American Male Preservice Teachers' Experiences with Stereotype Threat in Teacher Education

    Science.gov (United States)

    Scott, Sonya V.; Rodriguez, Louie F.

    2015-01-01

    This study draws from a larger phenomenological study on African American academic persistence and career aspirations in education. This article highlights three African American males' experiences with concentrated forms of stereotype threat in teacher education. Their voices revealed dimensions of how power and privilege operate in teacher…

  19. Fauna de flebotomíneos (Diptera: Psychodidae em fragmentos de floresta ao redor de conjuntos habitacionais na cidade de Manaus, Amazonas, Brasil. I. Estratificação Vertical Sand flies fauna (Diptera: Psychodidae in forest fragments around housing complexes in the Manaus municipality, state of Amazonas, Brazil. I. Vertical Stratification

    Directory of Open Access Journals (Sweden)

    Marlisson Augusto Costa Feitosa

    2006-12-01

    Full Text Available No período de janeiro a agosto de 1999 foram realizadas coletas de flebotomíneos (Diptera: Psychodidae em duas áreas de floresta residual (Estrada do Turismo e Cidade de Deus, na periferia da cidade de Manaus (AM, tendo o objetivo de verificar as espécies e a estratificação vertical. Foram utilizadas armadilhas luminosas tipo CDC, colocadas nos fragmentos de florestas a um e dez metros de altura. Foram capturados 7.516 flebotomíneos distribuídos em 45 espécies; 4.836 espécimes, de 36 espécies, na estrada de Turismo e 2.680 exemplares, de 40 espécies, na Cidade de Deus. Predominaram na Estrada do Turismo Lutzomyia umbratilis e L. ubiquitalis e na Cidade de Deus, L. umbratilis e L. anduzei. A presença de algumas espécies, apenas em certas áreas, indica a adaptabilidade destes flebotomíneos em áreas sobre ação antrópica.Between January and August of 1999, a study was carried out on the phlebotomine (Diptera: Psychodidae sand flies occurrence in two areas of residual forest (Estrada do Turismo and Cidade de Deus, in the periphery of Manaus, AM. The objective of this study was to verify the Phlebotominae sand fly fauna and vertical stratification. CDC light traps were placed in the forests, one to ten meters in height. A total of 7.516 sand flies, distributed in 45 species, were captured: 4.836 specimens of 36 species in the Estrada do Turismo and 2.680 individuals of 40 species in the Cidade de Deus.Predominant in the Estrada do Turismo were the species Lutzomyia umbratilis and L. ubiquitalis were as L. umbratilis and L. anduzei prevailed in the Cidade de Deus. Different Phlebotominae sand fly species in certain areas, showed an adaptation of these sand flies to areas of human activity.

  20. Intradermal Immunization of Leishmania donovani Centrin Knock-Out Parasites in Combination with Salivary Protein LJM19 from Sand Fly Vector Induces a Durable Protective Immune Response in Hamsters.

    Directory of Open Access Journals (Sweden)

    Jacqueline Araújo Fiuza

    2016-01-01

    Full Text Available Visceral leishmaniasis (VL is a neglected tropical disease and is fatal if untreated. There is no vaccine available against leishmaniasis. The majority of patients with cutaneous leishmaniasis (CL or VL develop a long-term protective immunity after cure from infection, which indicates that development of an effective vaccine against leishmaniasis is possible. Such protection may also be achieved by immunization with live attenuated parasites that do not cause disease. We have previously reported a protective response in mice, hamsters and dogs with Leishmania donovani centrin gene knock-out parasites (LdCen-/-, a live attenuated parasite with a cell division specific centrin1 gene deletion. In this study we have explored the effects of salivary protein LJM19 as an adjuvant and intradermal (ID route of immunization on the efficacy of LdCen-/- parasites as a vaccine against virulent L. donovani.To explore the potential of a combination of LdCen-/- parasites and salivary protein LJM19 as vaccine antigens, LdCen-/- ID immunization followed by ID challenge with virulent L. donovani were performed in hamsters in a 9-month follow up study. We determined parasite burden (serial dilution, antibody production (ELISA and cytokine expression (qPCR in these animals. Compared to controls, animals immunized with LdCen-/- + LJM19 induced a strong antibody response, a reduction in spleen and liver parasite burden and a higher expression of pro-inflammatory cytokines after immunization and one month post-challenge. Additionally, a low parasite load in lymph nodes, spleen and liver, and a non-inflamed spleen was observed in immunized animals 9 months after the challenge infection.Our results demonstrate that an ID vaccination using LdCen-/-parasites in combination with sand fly salivary protein LJM19 has the capability to confer long lasting protection against visceral leishmaniasis that is comparable to intravenous or intracardial immunization.

  1. Intradermal Immunization of Leishmania donovani Centrin Knock-Out Parasites in Combination with Salivary Protein LJM19 from Sand Fly Vector Induces a Durable Protective Immune Response in Hamsters

    Science.gov (United States)

    Fiuza, Jacqueline Araújo; Dey, Ranadhir; Davenport, Dwann; Abdeladhim, Maha; Meneses, Claudio; Oliveira, Fabiano; Kamhawi, Shaden; Valenzuela, Jesus G.; Gannavaram, Sreenivas; Nakhasi, Hira L.

    2016-01-01

    Background Visceral leishmaniasis (VL) is a neglected tropical disease and is fatal if untreated. There is no vaccine available against leishmaniasis. The majority of patients with cutaneous leishmaniasis (CL) or VL develop a long-term protective immunity after cure from infection, which indicates that development of an effective vaccine against leishmaniasis is possible. Such protection may also be achieved by immunization with live attenuated parasites that do not cause disease. We have previously reported a protective response in mice, hamsters and dogs with Leishmania donovani centrin gene knock-out parasites (LdCen-/-), a live attenuated parasite with a cell division specific centrin1 gene deletion. In this study we have explored the effects of salivary protein LJM19 as an adjuvant and intradermal (ID) route of immunization on the efficacy of LdCen-/- parasites as a vaccine against virulent L. donovani. Methodology/Principal Findings To explore the potential of a combination of LdCen-/- parasites and salivary protein LJM19 as vaccine antigens, LdCen-/- ID immunization followed by ID challenge with virulent L. donovani were performed in hamsters in a 9-month follow up study. We determined parasite burden (serial dilution), antibody production (ELISA) and cytokine expression (qPCR) in these animals. Compared to controls, animals immunized with LdCen-/- + LJM19 induced a strong antibody response, a reduction in spleen and liver parasite burden and a higher expression of pro-inflammatory cytokines after immunization and one month post-challenge. Additionally, a low parasite load in lymph nodes, spleen and liver, and a non-inflamed spleen was observed in immunized animals 9 months after the challenge infection. Conclusions Our results demonstrate that an ID vaccination using LdCen-/-parasites in combination with sand fly salivary protein LJM19 has the capability to confer long lasting protection against visceral leishmaniasis that is comparable to intravenous or

  2. Leishmaniose visceral: estudo de flebotomíneos e infecção canina em Montes Claros, Minas Gerais Visceral leishmaniasis: a study on phlebotomine sand flies and canine infection in Montes Claros, State of Minas Gerais

    Directory of Open Access Journals (Sweden)

    Érika Michalsky Monteiro

    2005-04-01

    Full Text Available A leishmaniose visceral no Brasil estava inicialmente associada a áreas rurais, mas devido às diversas alterações no ambiente como, desmatamentos, urbanização e intenso processo migratório, ocorreu a expansão das áreas endêmicas, levando à urbanização da doença, principalmente nas regiões Sudeste e Centro Oeste do país. No município de Montes Claros, situado ao norte de Minas Gerais, foi feito um estudo para verificação da situação da LV. No ano de 2002 foi realizado inquérito sorológico canino e no período de setembro de 2002 a agosto de 2003 foi feito levantamento entomológico, utilizando armadilhas luminosas de CDC. A prevalência da LV canina apresentou taxa média de infecção em torno de 5%. A fauna de flebotomíneos estimada foi de 16 espécies, totalizando 1043 exemplares. Lutzomyia longipalpis foi a espécie predominante com 74%, o que sugere a sua participação na transmissão de LV em Montes Claros.Visceral leishmaniasis in Brazil was initially associated with rural areas. However, due to several environmental modifications such as deforestation, urbanization and intense migratory processes, there has been an expansion of endemic areas, leading to urbanization of the disease, mainly in the central and northeastern regions of Brazil. In the municipality of Montes Claros, located in the north of the state of Minas Gerais, an epidemiological survey on VL was carried out. A canine serological inquiry was carried out in 2002 and an entomological survey, using luminous CDC traps, was performed from September 2002 to August 2003. Canine VL prevalence showed an average infection rate of approximately 5%. An estimated 16 species comprised the phlebotomine sand fly fauna, based on a total of 1043 specimens. The predominant species was Lutzomyia longipalpis with a rate of 74%, suggesting its participation in the transmission of VL in the municipality of Montes Claros.

  3. Construction procedures using self hardening fly ash

    Science.gov (United States)

    Thornton, S. I.; Parker, D. G.

    1980-07-01

    Fly ash produced in Arkansas from burning Wyoming low sulfur coal is self-hardening and can be effective as a soil stabilizing agent for clays and sands. The strength of soil-self hardening fly ash develops rapidly when compacted immediately after mixing. Seven day unconfined compressive strengths up to 1800 psi were obtained from 20% fly ash and 80% sand mixtures. A time delay between mixing the fly ash with the soil and compaction of the mixture reduced the strength. With two hours delay, over a third of the strength was lost and with four hours delay, the loss was over half. Gypsum and some commercial concrete retarders were effective in reducing the detrimental effect of delayed compaction. Adequate mixing of the soil and fly ash and rapid compaction of the mixtures were found to be important parameters in field construction of stabilized bases.

  4. Experimental Study of Preparation of C70 Manufactured Sand High Strength Concrete with Ultra-Fine Fly Ash%超细粉煤灰制备C70机制砂高强混凝土的试验研究

    Institute of Scientific and Technical Information of China (English)

    黄肖颖

    2013-01-01

    通过对超细粉煤灰掺量、水胶比、集料和胶凝材料体系等配合比参数进行设计和分析,利用超细粉煤灰制备出 C70机制砂高强混凝土,解决了机制砂高强混凝土拌合物黏度大的问题,并对混凝土耐久性能和收缩性能进行了评价。结果表明,该混凝土具有良好的工作性能、力学性能和耐久性能。%C70 manufactured sand high strength concrete was prepared by using ultra-fine fly ash, based on design and analysis of the mix proportion parameters of the ultra-fine fly ash content, water to binder ratio, aggregates and cmentitious materials. The problem of high viscosity of manufactured sand high strength concrete resolved. The performances of durability and shrinkage of concrete were evaluated. The results showed that the concrete had good workability,mechanical and durability properties.

  5. Geographical distribution of American cutaneous leishmaniasis and its phlebotomine vectors (Diptera: Psychodidae in the state of São Paulo, Brazil

    Directory of Open Access Journals (Sweden)

    Baton Luke

    2010-12-01

    Full Text Available Abstract Background American cutaneous leishmaniasis (ACL is a re-emerging disease in the state of São Paulo, Brazil. It is important to understand both the vector and disease distribution to help design control strategies. As an initial step in applying geographic information systems (GIS and remote sensing (RS tools to map disease-risk, the objectives of the present work were to: (i produce a single database of species distributions of the sand fly vectors in the state of São Paulo, (ii create combined distributional maps of both the incidence of ACL and its sand fly vectors, and (iii thereby provide individual municipalities with a source of reference material for work carried out in their area. Results A database containing 910 individual records of sand fly occurrence in the state of São Paulo, from 37 different sources, was compiled. These records date from between 1943 to 2009, and describe the presence of at least one of the six incriminated or suspected sand fly vector species in 183/645 (28.4% municipalities. For the remaining 462 (71.6% municipalities, we were unable to locate records of any of the six incriminated or suspected sand fly vector species (Nyssomyia intermedia, N. neivai, N. whitmani, Pintomyia fischeri, P. pessoai and Migonemyia migonei. The distribution of each of the six incriminated or suspected vector species of ACL in the state of São Paulo were individually mapped and overlaid on the incidence of ACL for the period 1993 to 1995 and 1998 to 2007. Overall, the maps reveal that the six sand fly vector species analyzed have unique and heterogeneous, although often overlapping, distributions. Several sand fly species - Nyssomyia intermedia and N. neivai - are highly localized, while the other sand fly species - N. whitmani, M. migonei, P. fischeri and P. pessoai - are much more broadly distributed. ACL has been reported in 160/183 (87.4% of the municipalities with records for at least one of the six incriminated or

  6. Impact of Phlebotomine Sand Flies on U.S. Military Operations at Tallil Air Base, Iraq: 1. Background, Military Situation, and Development of a ’Leishmaniasis Control Program’

    Science.gov (United States)

    2006-07-01

    tissue kit (QIAGEN, Valencia, CA). Complete details on this Leishmania - generic assay as well as L. major-, L. tropica -, and L. donovani–L. infantum...deployed to the Persian Gulf during operations Desert Shield and Desert Storm. Clin. Infect. Dis. 20: 1497Ð1504. Jacobson, R. L. 2003. Leishmania tropica ...individual soldiers were receiving many sand ßy bites in a single night, and 3) Leishmania parasites were present in 1.5% of the female sand ßies as

  7. Susceptibility of low-chill blueberry cultivars to Mediterranean fruit fly, oriental fruit fly, and melon fly (Diptera: Tephritidae).

    Science.gov (United States)

    Follett, Peter A; Zee, Francis T; Hamasaki, Randall T; Hummer, Kim; Nakamoto, Stuart T

    2011-04-01

    No-choice tests were conducted to determine whether fruit of southern highbush blueberry, Vaccinium corymbosum L., hybrids are hosts for three invasive tephritid fruit flies in Hawaii. Fruit of various blueberry cultivars was exposed to gravid female flies of Bactrocera dorsalis Hendel (oriental fruit fly), Ceratitis capitata (Wiedemann) (Mediterranean fruit fly), or Bactrocera cucurbitae Coquillet (melon fly) in screen cages outdoors for 6 h and then held on sand in the laboratory for 2 wk for pupal development and adult emergence. Each of the 15 blueberry cultivars tested were infested by oriental fruit fly and Mediterranean fruit fly, confirming that these fruit flies will oviposit on blueberry fruit and that blueberry is a suitable host for fly development. However, there was significant cultivar variation in susceptibility to fruit fly infestation. For oriental fruit fly, 'Sapphire' fruit produced an average of 1.42 puparia per g, twice as high as that of the next most susceptible cultivar 'Emerald' (0.70 puparia per g). 'Legacy', 'Biloxi', and 'Spring High' were least susceptible to infestation, producing only 0.20-0.25 oriental fruit fly puparia per g of fruit. For Mediterranean fruit fly, 'Blue Crisp' produced 0.50 puparia per g of fruit, whereas 'Sharpblue' produced only 0.03 puparia per g of fruit. Blueberry was a marginal host for melon fly. This information will aid in development of pest management recommendations for blueberry cultivars as planting of low-chill cultivars expands to areas with subtropical and tropical fruit flies. Planting of fruit fly resistant cultivars may result in lower infestation levels and less crop loss.

  8. Effect of Dosage of Fly Ash and Blast Furnace Slag on Performance of Concrete Prepared with Poorly Graded Sand%粉煤灰矿渣掺量对劣级配砂配制混凝土性能的影响

    Institute of Scientific and Technical Information of China (English)

    李茂红; 张雨杰; 陈航; 赵菊梅

    2015-01-01

    为生产优质的劣级配砂配制混凝土,通过调节粉煤灰矿渣掺量配制了6组劣级配砂配制混凝土,用Andreasen方程评价砂石堆积效应,并测试混凝土坍落度和抗压强度,研究粉煤灰矿渣掺量差异对劣级配砂配制混凝土工作性和抗压强度的影响。研究结果发现,劣级配砂与石混合仍可获得较紧密堆积,复掺40%粉煤灰、矿渣的混凝土及单掺30%粉煤灰的混凝土工作性满足泵送要求;各组混凝土56 d抗压强度均满足强度等级要求,且随粉煤灰含量增加混凝土抗压强度减小。可推断矿渣粉煤灰掺量对虽为劣级配砂配制但具有较紧密堆积混凝土工作性和抗压强度的影响,与对正常级配砂配制混凝土工作性和抗压强度的影响一致。%In order to fabricate high quality concrete using poorly graded sand,six groups of concrete with poor sand gradation were prepared with different dosages of fly ash (FA)and blast furnace slag (BFS). The sand and stone compactness of the concrete was evaluated using the Andreasen equation, and the slump and compressive strength of the concrete were tested to study the effect of the dosage of fly ash and blast furnace slag on the workability and compressive strength of the concrete prepared with poor sand gradation. The results showed that the poorly graded sand and crushed stones had an adequately dense packing;both the concrete groups with 40% FA +BFS replacement and 30% FA replacement satisfied the pumping requirement;the concrete compressive strength in each group at 56 d satisfied the requirement of the strength grade,and decreased with the increasing of the dosage of fly ash. Therefore,the effect of the FA and BFS dosage on the workability and compressive strength of the concrete with poor sand gradation and dense packing is similar to that on the concrete with normal sand gradation.

  9. Flying Scared

    DEFF Research Database (Denmark)

    Dal Sie, Marco; Josiassen, Alexander

    service quality expectations and fear of flying affect travellers' flight choices on long-haul flights. The study was set in Bangkok and primary data were obtained from a large sample of travelers departing from Suvarnabhumi Airport. While service quality emerged as a relevant factor, fear of flying didn...

  10. Phlebotomine sand flies and canine infection in areas of human visceral leishmaniasis, Cuiabá, Mato Grosso Flebotomíneos e infecção canina em áreas de leishmaniose visceral humana, Cuiabá, Mato Grosso

    Directory of Open Access Journals (Sweden)

    Gustavo Leandro da Cruz Mestre

    2011-09-01

    Full Text Available Visceral leishmaniasis is a systemic infectious disease that can cause to a severe, potentially life-threatening chronic condition in humans. Risk factors for infection in urban areas have been associated with poor living conditions, the presence of sand fly vectors and infected pets. This study aimed to describe sand fly and canine infection in the neighborhoods of human visceral leishmaniasis occurrence in the city of Cuiabá, Mato Grosso State, central-western Brazil, reported between January 2005 and December 2006. A total of 1,909 sand flies were collected. They were predominantly males and the most frequent species were Lutzomyia cruzi (81.25%, Lutzomyia whitmani (13.88% and Lutzomyia longipalpis (2.62%. The sand fly density was not significantly correlated with the variation of environmental factors. The prevalence of canine visceral leishmaniasis in the neighborhoods studied was 26.82% and it was found that areas with high density of vectors coincided with areas of high prevalence of dogs and those with the highest rates of human cases. The study of vectors and other potential hosts are essential for a good understanding of visceral leishmaniasis and the related public health concerns, aiming at the prevention and control of leishmaniasis in the city of Cuiabá, Mato Grosso State.A leishmaniose visceral é uma doença infecciosa sistêmica, de evolução crônica grave, potencialmente fatal para o homem. Os fatores de risco para a infecção em áreas urbanas têm sido associados às precárias condições de moradia, à presença de flebotomíneos vetores e de animais domésticos infectados. O presente trabalho objetivou descrever a fauna flebotomínica e infecção canina nos bairros de ocorrência da leishmaniose visceral humana no município de Cuiabá, Mato Grosso, notificados no período de janeiro de 2005 a dezembro de 2006. Foram coletados 1.909 flebotomíneos, as espécies mais frequentes foram Lutzomyia cruzi (81,25%, Lutzomyia

  11. The cumulative effects of using fine particles and cyanobacteria for rehabilitation of disturbed active sand dunes

    Science.gov (United States)

    Zaady, Eli; Katra, Itzhak; Barkai, Daniel; Knoll, Yaakov; Sarig, Shlomo

    2016-04-01

    One of the main problems in desertified lands worldwide is active wind-borne sand dunes, which lead to covering of fertile soils and agricultural fields. In regions with more than 100 mm of annual rainfall, sand dunes may be naturally stabilized by biocrusts (biological soil crusts). One of the main restraints of biocrust development is the typical lack of fine particles in sand dunes. Our study investigated the combined application of fine particles [coal fly-ash <100 micrometer] and bio-inoculant of filamentous cyanobacteria, isolated from nearby natural stabilized sand dunes, on the soil surface of active sands for increasing resistance to wind erosion. Boundary-layer wind tunnel experiments were conducted in experimental plots within a greenhouse for examining the effects of adding coal fly-ash and bio-inoculant to active sands. The biocrust development was evaluated via several physical and bio-physiological variables. In all the physical measurements and the bio-physiological variables, the treatment of "sand+inoculum+coal fly-ash" showed significant differences from the "sand-control". The combination led to the best results of surface stabilization in boundary-layer wind tunnel experiments, with the lowest sand fluxes. The filamentous cyanobacteria use the fine particles of the coal fly-ash as bridges for growing toward and adhering to the large sand particles. The cumulative effects of biocrusts and coal fly-ash enhance soil surface stabilization and may allow long-term sustainability.

  12. Tar sand

    Energy Technology Data Exchange (ETDEWEB)

    McLendon, T.R.; Bartke, T.C.

    1990-01-01

    Research on tar sand is briefly discussed. The research program supported by the US Department of Energy (DOE) includes a variety of surface extraction schemes. The University of Utah has process development units (PDU) employing fluidized bed, hot, water-assisted, and fluidized-bed/heat-pipe, coupled combustor technology. Considerable process variable test data have been gathered on these systems: (1) a rotary kiln unit has been built recently; (2) solvent extraction processing is being examined; and (3) an advanced hydrogenation upgrading scheme (hydropyrolysis) has been developed. The University of Arkansas, in collaboration with Diversified Petroleum, Inc., has been working on a fatty acid, solvent extraction process. Oleic acid is the solvent/surfactant. Solvent is recovered by adjusting processing fluid concentrations to separate without expensive operations. Western Research Institute has a PDU-scale scheme called the Recycle Oil Pyrolysis and Extraction (ROPE) process, which combines solvent (hot recycle bitumen) and pyrolytic extraction. 14 refs., 19 figs.

  13. Geological behavior of wet outflow deposition fly ash

    Institute of Scientific and Technical Information of China (English)

    周德泉; 赵明华; 刘宏利; 周毅; 严聪

    2008-01-01

    The geological behaviors of wet outflow deposition fly ash were investigated, including the feature of in-situ single and even bridge cone penetration test (CPT) curves, the change of the penetration parameters and vane strength with the increase of depth and the difference of the penetration resistance on and down the water level. Drilling, CPT and vane shear test were carried out in silty clay, fine sand, and fly ash of the ash-dam. The CPT curves of the fly ash do not show a critical depth. The cone resistance (qc) of the fly ash is smaller than that of silty clay or sand; the friction resistance is smaller than that of filling silty clay, similar to that of deposition silty clay or more than that of fine sand; the friction ratio is smaller than that of filling silty clay, or more than that of deposition silty clay or much more than that of fine sand. The specific penetration resistance (ps) is similar to that of filling silty clay, or more than that of deposition silty clay. There is a clear interface effect between the deposition fly ash and the clay. Interface effect of ps-h curve at the groundwater table is clear, and ps of the fly ash reduces significantly under the table. The vane strength of the fly ash increases as the depth increases. The deposition fly ash with wet outflow is similar to silt in the geological behavior.

  14. It's in the sand

    OpenAIRE

    Mitchell, Clive

    2016-01-01

    Sand is sand isn’t it? Sand gets everywhere but rather than a nuisance it is a valuable, high-purity raw material. Clive Mitchell, Industrial Minerals Specialist at the British Geological Survey (BGS), talks us through what sand is, what it can be used for and how to find it. His exploration of sand takes us from the deserts of Arabia to the damp sand pits of Mansfield!

  15. Sequence variation in the melanocortin-1 receptor (MC1R pigmentation gene and its role in the cryptic coloration of two South American sand lizards

    Directory of Open Access Journals (Sweden)

    Josmael Corso

    2012-01-01

    Full Text Available In reptiles, dorsal body darkness often varies with substrate color or temperature environment, and is generally presumed to be an adaptation for crypsis or thermoregulation. However, the genetic basis of pigmentation is poorly known in this group. In this study we analyzed the coding region of the melanocortin-1-receptor (MC1R gene, and therefore its role underlying the dorsal color variation in two sympatric species of sand lizards (Liolaemus that inhabit the southeastern coast of South America: L. occipitalis and L. arambarensis. The first is light-colored and occupies aeolic pale sand dunes, while the second is brownish and lives in a darker sandy habitat. We sequenced 630 base pairs of MC1R in both species. In total, 12 nucleotide polymorphisms were observed, and four amino acid replacement sites, but none of them could be associated with a color pattern. Comparative analysis indicated that these taxa are monomorphic for amino acid sites that were previously identified as functionally important in other reptiles. Thus, our results indicate that MC1R is not involved in the pigmentation pattern observed in Liolaemus lizards. Therefore, structural differences in other genes, such as ASIP, or variation in regulatory regions of MC1R may be responsible for this variation. Alternatively, the phenotypic differences observed might be a consequence of non-genetic factors, such as thermoregulatory mechanisms.

  16. Time flies

    DEFF Research Database (Denmark)

    Wit, Janneke

    , the LS fly might be able to spend energy more generously on different tasks. Therefor, the capacity of LS and C lines to locate resources in a natural environment was tested. It turns out that LS flies are less likely to find food than C flies in such a setting, yet that as they age, their ability...... to locate food decreases slower than that of C lines. Gene expression of 10 candidate genes for longevity was quantified in two types of C and LS lines at three different ages. One of these genes, CG32638, indeed appears to be involved in life span determination in both males and females, regardless...... of mating status. Generalising studies on ageing in D. melanogaster can be cumbersome, especially in light of discrepancy between correlated responses between studies. To elucidate which mechanisms might be conserved due to evolutionary constraints, life span of 13 species of Drosophila was determined...

  17. 风积砂质高浓度胶凝充填材料性能与粉煤灰掺量关系分析%RELATIONSHIP BETWEEN ENGINEERING PERFORMANCE AND MIX PROPORTION OF FLY ASH FOR CEMENTED AND HIGH CONCENTRATION BACKFILL MATERIAL WITH WIND-BLOWN SAND AS AGGREGATE

    Institute of Scientific and Technical Information of China (English)

    王晓东

    2016-01-01

    In coal mining with backfill,backfill material dominates the benefit,efficiency and effect.In order to get the characteristics varying pattern of cemented and high concentration backfill material with wind-blown sand as aggregate,fly ash is selected as variables to test and analyze the characteristics varying pattern of backfill material with the mix proportion of fly ash.The results show that,as the mix proportion of fly ash increases in a proper range in backfill material,the compressive strength increases,the bleeding rate decreases in general,the layered degree declines by linear pattern,the coagulation time grows up by exponential pattern,and the slump is growing consecutively.But,with the higher mix proportion of fly ash,the compressive strength and slump will drop comparatively.When the mix proportion of fly ash is in proper range,the fly ash optimizes the particle size gradient of backfill material,and makes water and cement distribution uniform in backfill material.As a result,the strength characteristic and rheological performance can be improved.However,some characteristics will degenerate with higher mix proportion of fly ash.%充填材料是决定煤炭充填开采效益、效率、效果的最主要因素.为了掌握风积砂质高浓度胶凝充填材料的性能变化规律,本文以粉煤灰的质量掺入比作为变量,试验研究和理论分析了粉煤灰对该充填材料性能的影响规律.结果表明,粉煤灰的适量添加可以提高充填材料的强度,大掺量导致强度相对降低;泌水率随着粉煤灰掺量的增大总体上呈减小趋势,较大掺量试样泌水速率相对较低;分层度随着粉煤灰掺量的增大线性降低;凝结时间随着粉煤灰掺量增大呈现指数增大;坍落度总体上随粉煤灰掺量的升高而增大,但大掺量会使其出现相对降低.分析认为,适量粉煤灰的掺入,使风积砂质高浓度胶凝充填材料的颗粒粒度、水分分布和水泥分散均匀,而使材

  18. Industrial sand and gravel

    Science.gov (United States)

    Dolley, T.P.

    2013-01-01

    Domestic production of industrial sand and gravel in 2012 was about 49.5 Mt (55 million st), increasing 13 percent compared with that of 2011. Some important end uses for industrial sand and gravel include abrasives, filtration, foundry, glassmaking, hydraulic fracturing sand (frac sand) and silicon metal applications.

  19. Assessment of sand fly (Diptera, Psychodidae control using cypermethrin in an endemic area for visceral leishmaniasis, Montes Claros, Minas Gerais State, Brazil Avaliação do controle de flebotomíneos (Diptera, Psychodidae usando cipermetrina em área endêmica para leishmaniose visceral, Montes Claros, Minas Gerais, Brasil

    Directory of Open Access Journals (Sweden)

    Ricardo Andrade Barata

    2011-11-01

    Full Text Available Montes Claros in Minas Gerais State, Brazil, was considered an intense transmission area for visceral leishmaniasis. This study evaluated sand fly fauna after insecticide application. Captures were performed in 10 districts from September 2005 to August 2006 with CDC light traps inside and outside each residence. Cypermethrin was sprayed in two cycles during November/2005 and May/2006. The 636 specimens collected, belonging to 10 species, were predominantly Lutzomyia longipalpis (79%, and most frequently males (70%. The highest percentage of specimens were captured in areas surrounding domiciles (85.8%. The main species were observed to be sensitive to treatment with the insecticide. The results showed a reduction in the number of sand flies collected after use of cypermethrin in homes and annexes, and with residual effect lasting from two to four months.Montes Claros foi considerada área de transmissão intensa para leishmaniose visceral no Estado de Minas Gerais, Brasil. Este trabalho avaliou a fauna de flebotomíneos após a aplicação do inseticida. Entre setembro de 2005 e agosto de 2006, foram realizadas capturas com 20 armadilhas luminosas CDC em 10 bairros do município, no intra e no peridomicílio de cada residência. Dois ciclos de borrifação com cipermetrina foram realizados nos meses de novembro/2005 e maio/2006. Coletou-se 636 exemplares pertencentes a 10 espécies, com predominância de Lutzomyia longipalpis (79%. Machos foram coletados com maior frequência (70%. O peridomicílio apresentou a maior porcentagem dos espécimens capturados (85,8%. Observou-se que as principais espécies foram sensíveis ao tratamento com o inseticida. Os resultados mostraram uma redução do número de flebotomíneos coletados devido ao uso de cipermetrina nos domicílios e seus anexos, mas com efeito residual atuante entre dois e quatro meses.

  20. Flebotomíneos de várzea do rio Aguapeí, região noroeste do Estado de São Paulo, Brasil Sand flies in the Aguapeí river floodplain, northwest area of State of São Paulo, Brazil

    Directory of Open Access Journals (Sweden)

    Rosa M F N Odorizzi

    2007-08-01

    Full Text Available OBJETIVO: Investigar a sazonalidade de flebotomíneos de acordo com sua ocorrência e densidade. MÉTODOS: A pesquisa for realizada em área de várzea do rio Aguapeí, do município de Mirandópolis, Estado de São Paulo. Os flebotomíneos foram capturados mensalmente com armadilhas automáticas luminosas, instaladas das 18:00 às 7:00 horas, durante um ano (2004-2005, em dois locais: varanda de um rancho de pesca e mata. Utilizou-se a média de Williams para o cálculo da sazonalidade dos flebotomíneos e teste de qui-quadrado para comparação. RESULTADOS: Foram capturados 35.995 flebotomíneos. Cinco espécimes eram Brumptomyia avellari, um Psathyromyia (Xiphomyia hermanlenti e os demais Nyssomyia neivai, que apresentou freqüência mais elevada no inverno. É o primeiro registro de Ps. hermanlenti no Estado. CONCLUSÕES: A alta densidade de Nyssomyia neivai, um dos vetores suspeitos de transmitir a leishmaniose tegumentar americana, aponta o risco de transmissão dessa doença no local, principalmente nos períodos mais secos do ano.OBJECTIVE: To investigate the seasonal variation of sand flies regarding their occurrences and densities. METHODS: The study was conducted in the Aguapeí river floodplain in the state of São Paulo, southeastern Brazil. Sand flies were monthly captured with automatic light traps set up between 18:00 and 7:00 hours, over a period of one year (2004-2005, at two sites: veranda of a domicile and in a forest on the banks of Aguapeí River. The Williams' average was used for estimating the seasonal variation and the Chi-square test for comparison. RESULTS: A total of 35,995 specimens were captured: five Brumptomyia avellari, one Psathyromyia (Xiphomyia hermanlenti and the rest Nyssomyia neivai, which had the highest frequency during the winter. Ps. hermanlenti is first recorded in state of São Paulo. CONCLUSIONS: The high density of Nyssomyia neivai, a suspected vector of cutaneous leishmaniasis, points out to the

  1. Flying Cities

    DEFF Research Database (Denmark)

    Herbelin, Bruno; Lasserre, Sebastien; Ciger, Jan

    2008-01-01

    Flying Cities is an artistic installation which generates imaginary cities from the speech of its visitors. Thanks to an original interactive process analyzing people's vocal input to create 3D graphics, a tangible correspondence between speech and visuals opens new possibilities of interaction. ...... and a potential application. We believe that it could become a new medium for creativity, and a way to visually perceive a vocal performance in the context of the rehabilitation of people with reduced mobility or language impairments....

  2. The transmission of suprapylarian Leishmania by bite of experimentally infected sand flies (Diptera: Psychodidae A trasnmissão de Leishmania suprapilária pela picada do flebotomíneo infectado experimentalmente

    Directory of Open Access Journals (Sweden)

    L. Ryan

    1987-09-01

    Full Text Available Lutzomyia furcata transmitted Leishmania chagasi to a hamster 10 days after being experimentally fed on an infected spleen. An individual female Psychodopygus carrerai carrerai that had fed on a hamster lesion caused by Leishmania mexicana amazonensis transmitted this parasite 6 days later to another hamster. Transmission electron microscopy of this fly's head revealed a small number of degenerate promastigotes in the foregut, but only a few were attached.O protozoário Leishmania (L. chagasi foi transmitido experimentalmente a um hamster pela picada do flebotomíneo Lutzomyia furcata. Os insetos foram infectados através de uma membrana (pele de pinto, utilizando-se formas amastigotas provenientes do baço de um hamster infectado. O baço foi triturado em sangue de coelho. A L. (L. amazonensis foi transmitida a um hamster pela picada do flebotomíneo Psychodopygus c. carrerai, previamente alimentado em lesão de pele de um outro hamster infectado com o parasita. O exame desse flebotomíneo, através de microscópio eletrônico, revelou um número pequeno de flagelados degenerados, livres no lumen do intestino anterior.

  3. Influence green sand system by core sand additions

    OpenAIRE

    N. Špirutová; J. Beňo; V. Bednářová; J. Kříž; M. Kandrnál

    2012-01-01

    Today, about two thirds of iron alloys casting (especially for graphitizing alloys of iron) are produced into green sand systems with usually organically bonded cores. Separation of core sands from the green sand mixture is very difficult, after pouring. The core sand concentration increase due to circulation of green sand mixture in a closed circulation system. Furthermore in some foundries, core sands have been adding to green sand systems as a replacement for new sands. The goal of this co...

  4. Flying Cities

    DEFF Research Database (Denmark)

    Ciger, Jan

    2006-01-01

    of providing a tangible correspondence between the two spaces. This interaction mean has proved to suit the artistic expression well but it also aims at providing anyone with a pleasant and stimulating feedback from speech activity, a new medium for creativity and a way to visually perceive a vocal performance....... As the feedback we have received when presenting Flying Cities was very positive, our objective now is to cross the bridge between art and the potential applications to the rehabilitation of people with reduced mobility or for the treatment of language impairments....

  5. Flying Fortress

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    当欧洲的年轻人想到关于德国的两种熊,一个是传统的布娃娃熊,另一个就是充满欧洲街头墙上的Teddy熊涂鸦,而这个涂鸦熊的创作者就是著名的涂鸦艺术家“Flying Fortress”,他称这些熊军队为“Teddy Tmops”。

  6. Studies on the Feeding Habits of Lutzomyia (Lutzomyia longipalpis (Lutz & Neiva, 1912 (Diptera: Psychodidae: Phlebotominae Populations from Endemic Areas of American Visceral Leishmaniasis in Northeastern Brazil

    Directory of Open Access Journals (Sweden)

    Margarete Martins dos Santos Afonso

    2012-01-01

    Full Text Available The aim of this study was to identify potential blood feeding sources of L. (L. longipalpis specimens from populations in Northeastern Brazil, endemic areas of American Visceral Leishmaniasis (AVL and its correlation with the transmission of L. (L. i. chagasi. The ELISA technique was applied using bird, dog, goat, opossum, equine, feline, human, sheep, and rodent antisera to analyze 609 females, resulting in an overall positivity of 60%. In all municipalities, females showed higher positivity for bird followed by dog antiserum and sand fly specimens were also positive for equine, feline, human, sheep, goat, opossum, and rodent antisera. The finding for 17 combinations of two or three types of blood in some females corroborates the opportunistic habit of this sand fly species. The results demonstrating the association between L. (L. longipalpis and opossum suggest the need for further evaluation of the real role of this synanthropic mammal in the eco-epidemiology of AVL.

  7. Phlebotominae fauna in a recent deforested area with American tegumentary leishmaniasis transmission (Puerto Iguazú, Misiones, Argentina): seasonal distribution in domestic and peridomestic environments.

    Science.gov (United States)

    Fernández, María Soledad; Lestani, Eduardo Ariel; Cavia, Regino; Salomón, Oscar Daniel

    2012-04-01

    Phlebotominae sand flies have been involved as vectors of Leishmania. In Argentina, Nyssomyia neivai and Nyssomyia whitmani are involved as the main vectors of American Tegumentary Leishmaniasis (ATL). In the northeastern border of the country, an outbreak of ATL during 2004-2005 was associated with deforestation and subsequent settlement of farmers close to the edge of the forest. The aim of this work was to study the community composition of sand flies along time in farms located near primary and secondary forest in two environments: houses and pigsties. The association of abundance with temperature and precipitation was also evaluated for the most prevalent species. A total of 23,659 Phlebotominae belonging to the genera Nyssomyia, Migonemyia, Pintomyia, Evandromyia, Micropygomyia, Sciopemyia, Dampfomyia, Psathyromyia and Brumptomyia were captured. Ny. whitmani, which was the most abundant species, and Migonemyia migonei, which was the second most abundant species, were present throughout the year. Both species were positively associated with temperature, mostly up to 31-47 days, and with precipitation at 31 days before the sampling day. The abundance was higher in pigsties than in houses, but the time pattern was positively associated between both environments. These results confirm that Ny. whitmani is the dominant species in the study area and its presence throughout the year indicates a potential long period of ATL transmission. The presence of Mg. migonei as the second species in abundance is relevant, because it has been described as a secondary vector of the parasites of ATL and a putative vector of the agent of American Visceral Leishmaniasis. We discuss the role of the pigsty as the environment that attract more sandflies, taking into account the number of sand flies captured there, the distance from the home, and the association of sand fly abundance with each of the two environments.

  8. Simulating and understanding sand wave variation: A case study of the Golden Gate sand waves

    Science.gov (United States)

    Sterlini, F.; Hulscher, S.J.M.H.; Hanes, D.M.

    2009-01-01

    In this paper we present a detailed comparison between measured features of the Golden Gate sand wave field and the results of a nonlinear sand wave model. Because the Golden Gate sand waves exhibit large variation in their characteristics and in their environmental physics, this area gives us the opportunity to study sand wave variation between locations, within one well-measured, large area. The nonlinear model used in this paper is presently the only tool that provides information on the nonlinear evolution of large-amplitude sand waves. The model is used to increase our understanding of the coupling between the variability in environmental conditions and the sand wave characteristics. Results show that the model is able to describe the variation in the Golden Gate sand waves well when both the local oscillating tidal current and the residual current are taken into account. Current and water depth seem to be the most important factors influencing sand wave characteristics. The simulation results give further confidence in the underlying model hypothesis and assumptions. Copyright 2009 by the American Geophysical Union.

  9. Flying High

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ Eric Ransdell looks at the world through a softerfocus lens these days. The former war correspondent made his name interviewing machine-gun-toting rebels in Africa.Nowadays,the 44-year-old American is more likely to be found shooting corporate promotional videos in Shanghai.

  10. Evaluation of fly ash as a component of potting substrates

    Energy Technology Data Exchange (ETDEWEB)

    Menzies, N.W.; Aitken, R.L. [University of Queensland, St. Lucia, Qld. (Australia). Dept. of Agriculture

    1996-11-01

    A series of laboratory and glasshouse experiments were undertaken to assess the potential for incorporating fly ash in soilless potting substrates. Since fly ash is available at low cost and can be successfully substituted for a considerable portion of the expensive peat component in the peat:sand mix, its use at low application rates in potting substrates may be desirable from an economic viewpoint.

  11. Influence green sand system by core sand additions

    Directory of Open Access Journals (Sweden)

    N. Špirutová

    2012-01-01

    Full Text Available Today, about two thirds of iron alloys casting (especially for graphitizing alloys of iron are produced into green sand systems with usually organically bonded cores. Separation of core sands from the green sand mixture is very difficult, after pouring. The core sand concentration increase due to circulation of green sand mixture in a closed circulation system. Furthermore in some foundries, core sands have been adding to green sand systems as a replacement for new sands. The goal of this contribution is: “How the green sand systems are influenced by core sands?”This effect is considered by determination of selected technological properties and degree of green sand system re-bonding. From the studies, which have been published yet, there is not consistent opinion on influence of core sand dilution on green sand system properties. In order to simulation of the effect of core sands on the technological properties of green sands, there were applied the most common used technologies of cores production, which are based on bonding with phenolic resin. Core sand concentration added to green sand system, was up to 50 %. Influence of core sand dilution on basic properties of green sand systems was determined by evaluation of basic industrial properties: moisture, green compression strength and splitting strength, wet tensile strength, mixture stability against staling and physical-chemistry properties (pH, conductivity, and loss of ignition. Ratio of active betonite by Methylene blue test was also determined.

  12. Flowable fill using waste foundry sand: A substitute for compacted or stabilized soil

    Energy Technology Data Exchange (ETDEWEB)

    Bhat, S.T.; Lovell, C.W. [Purdue Univ., West Lafayette, IN (United States). School of Civil Engineering

    1997-12-31

    Flowable fill is generally a mixture of sand, fly ash, a small amount of cement, and water. Sand is the major component of most flowable fill mixes; consequently, using a waste material as a substitute for natural sand results in the beneficial use of the waste material. Waste foundry sand (WFS) was used as a fine aggregate in this study. Three green sands from ferrous foundries and two class F fly ashes were used. The flow behavior, hardening characteristics, ultimate strength behavior, and permeability characteristics of flowable fill were investigated. The penetration resistance necessary to sustain walkability as the fresh flowable fill hardens was determined. The pH of pore solution of hardened flowable fill indicated that the potential for corrosivity is low. The toxicity tests indicated that some WFSs are environmentally safe.

  13. Estimating Orientation of Flying Fruit Flies.

    Directory of Open Access Journals (Sweden)

    Xi En Cheng

    Full Text Available The recently growing interest in studying flight behaviours of fruit flies, Drosophila melanogaster, has highlighted the need for developing tools that acquire quantitative motion data. Despite recent advance of video tracking systems, acquiring a flying fly's orientation remains a challenge for these tools. In this paper, we present a novel method for estimating individual flying fly's orientation using image cues. Thanks to the line reconstruction algorithm in computer vision field, this work can thereby focus on the practical detail of implementation and evaluation of the orientation estimation algorithm. The orientation estimation algorithm can be incorporated into tracking algorithms. We rigorously evaluated the effectiveness and accuracy of the proposed algorithm by running experiments both on simulation data and on real-world data. This work complements methods for studying the fruit fly's flight behaviours in a three-dimensional environment.

  14. Baskarp Sand No. 15

    DEFF Research Database (Denmark)

    Ibsen, Lars Bo; Bødker, Lars Bødker

    The Soil Mechanics Laboratory has started performing tests with a new sand, Baskarp No 15. Baskarp No 15 is a graded sand from Sweden. The shapes of the largest grains are round, while the small grains have sharp edges. The main part of of Baskarp No 15 is quarts, but it also contains feldspar...

  15. Sands cykliske styrke

    DEFF Research Database (Denmark)

    Ibsen, Lars Bo

    1992-01-01

    Sands cykliske styrke kan beskrives ved Cyclic Liquefaction, Mobilisering, Stabilization og Instant Stabilization. I artiklen beskrives hvorfor Stabilization og Instant Stabilization ikke observeres, når sands udrænede styrke undersøges i triaxial celler, der anvender prøver med dobbelt prøvehøjde....

  16. Flying insects and Campylobacter

    DEFF Research Database (Denmark)

    Hald, Birthe; Sommer, Helle Mølgaard; Skovgård, Henrik

    to broiler houses may be counted in thousands per broiler rotation during summer periods, even a low prevalence of Campylobacter positive flies constitute a risk of introduction of Campylobacter to the chickens. M. domestica – the house fly is the most important vector fly for Campylobacter transmission...... organisms, which may collect on their bodies or survive passage through the fly gut. Campylobacter and other pathogens are then easily transferred to other surfaces, for instance peoples food – or to broiler houses where they may be swallowed by chickens or contaminate the environment. On a large material...... of several species of flies collected outside broiler houses, merely ~1% of the flies were found Campylobacter positive. However, the prevalence varied considerably with fly species, time of the year, and availability of Campylobacter sources. Influx of flies to broiler houses As the influx of flies...

  17. Biofuel Combustion Fly Ash Influence on the Properties of Concrete

    Directory of Open Access Journals (Sweden)

    Aurelijus Daugėla

    2016-02-01

    Full Text Available Cement as the binding agent in the production of concrete can be replaced with active mineral admixtures. Biofuel combustion fly ash is one of such admixtures. Materials used for the study: Portland cement CEM I 42.5 R, sand of 0/4 fraction, gravel of 4/16 fraction, biofuel fly ash, superplasticizer, water. Six compositions of concrete were designed by replacing 0%, 5%, 10%, 15% 20%, and 25% of cement with biofuel fly ash. The article analyses the effect of biofuel fly ash content on the properties of concrete. The tests revealed that the increase of biofuel fly ash content up to 20% increases concrete density and compressive strength after 7 and 28 days of curing and decreases water absorption, with corrected water content by using plasticizing admixture. It was found that concrete where 20% of cement is replaced by biofuel ash has higher frost resistance.

  18. Chronic Ingestion of Coal Fly-Ash Contaminated Prey and Its Effects on Health and Immune Parameters in Juvenile American Alligators (Alligator mississippiensis).

    Science.gov (United States)

    Finger, John W; Hamilton, Matthew T; Metts, Brian S; Glenn, Travis C; Tuberville, Tracey D

    2016-10-01

    Coal-burning power plants supply approximately 37 % of the electricity in the United States. However, incomplete combustion produces ash wastes enriched with toxic trace elements that have historically been disposed of in aquatic basins. Organisms inhabiting such habitats may accumulate these trace elements; however, studies investigating the effects on biota have been primarily restricted to shorter-lived, lower-trophic organisms. The American alligator (Alligator mississippiensis), a long-lived, top-trophic carnivore, has been observed inhabiting these basins, yet the health or immune effects of chronic exposure and possible accumulation remains unknown. In this study, we investigated how chronic dietary ingestion of prey contaminated with coal combustion wastes (CCWs) for 25 months, and subsequent accumulation of trace elements present in CCWs, affected juvenile alligator immune function and health. Alligators were assigned to one of four dietary-treatment groups including controls and those fed prey contaminated with CCWs for one, two, or three times a week. However, no effect of Dietary Treatment (p > 0.05) was observed on any immune parameter or hematological or plasma analyte we tested. Our results suggest that neither exposure to nor accumulation of low doses of CCWs had a negative effect on certain aspects of the immune and hematological system. However, future studies are required to elucidate this further.

  19. Courtship song genes and speciation in sand flies

    Directory of Open Access Journals (Sweden)

    Oliveira SG

    2001-01-01

    Full Text Available Lutzomyia longipalpis (Lutz & Neiva, 1912 (Diptera: Psychodidae: Phlebotominae is a vector of visceral leishmaniasis in the Americas and it might represent a complex of sibling species. Reproductive isolation between closely related species often involves differences in courtship behaviour. cacophony (cac and period (per are two Drosophila genes that control features of the "lovesong" males produce during courtship that has been implicated in the sexual isolation between closely related species. We are using gene fragments from L. longipalpis' homologues of these two genes to study the speciation process in this putative species complex.

  20. Insecticide-Treated Rodent Baits for Sand Fly Control

    Science.gov (United States)

    2013-04-28

    Louisiana State University Agricultural Center, Department of Entomology , Baton Rouge, LA, USA b Louisiana State University School of Veterinary Medicine...Sciences, Bethesda, MD, USA dWalter Reed Army Institute of Research, Silver Spring, MD, USA eUS Army Medical Research Unit-Kenya, Unit 8900, Box 6801...State University Agricultural Center, Agricultural Experiment Station, Department of Entomology , 402 Life Sciences, Baton Rouge, LA 70803, USA. Fax: +1

  1. Sand and Gravel Deposits

    Data.gov (United States)

    Vermont Center for Geographic Information — This dataset is a statewide polygon coverage of sand, gravel, and stone resources. This database includes the best data available from the VT Agency of Natural...

  2. Applications of fly ash in synthesizing low-cost MMCs for automotive and other applications

    Science.gov (United States)

    Rohatgi, P. K.; Weiss, D.; Gupta, Nikhil

    2006-11-01

    This paper summarizes attempts to incorporate fly ash into aluminum castings to decrease the energy content, material content, cost, and weight of selected industrial components, while also improving selected properties. It is shown that fly ash can be incorporated into an aluminum-alloy matrixusing stir casting and pressure infiltration techniques. The sand and permanent mold castings, which included differential vovers, intake manifolds brake drums, and outdoor equipment castings including post caps, demonstrate adequate castability of aluminum melts containing up to 10 vol.% fly-ash particles. The potential cost, energy, and pollution savings as a result of incorporation of fly ash in aluminum are discussed in the paper.

  3. Bituminous sands : tax issues

    Energy Technology Data Exchange (ETDEWEB)

    Patel, B. [PricewaterhouseCoopers LLP, Calgary, AB (Canada)

    2004-07-01

    This paper examined some of the tax issues associated with the production of bitumen or synthetic crude oil from oil sands. The oil sands deposits in Alberta are gaining more attention as the supplies of conventional oil in Canada decline. The oil sands reserves located in the Athabasca, Cold Lake and Peace River areas contain about 2.5 trillion barrels of highly viscous hydrocarbons called bitumen, of which nearly 315 billion barrels are recoverable with current technology. The extraction method varies for each geographic area, and even within zones and reservoirs. The two most common extraction methods are surface mining and in-situ extraction such as cyclic steam stimulation (CSS); low pressure steam flood; pressure cycle steam drive; steam assisted gravity drainage (SAGD); hot water flooding; and, fire flood. This paper also discussed the following general tax issues: bituminous sands definition; bituminous sands leases and Canadian development expense versus Canadian oil and gas property expense (COGPE); Canadian exploration expense (CEE) for surface mining versus in-situ methods; additional capital cost allowance; and, scientific research and experimental development (SR and ED). 15 refs.

  4. Fly ash carbon passivation

    Science.gov (United States)

    La Count, Robert B; Baltrus, John P; Kern, Douglas G

    2013-05-14

    A thermal method to passivate the carbon and/or other components in fly ash significantly decreases adsorption. The passivated carbon remains in the fly ash. Heating the fly ash to about 500 and 800 degrees C. under inert gas conditions sharply decreases the amount of surfactant adsorbed by the fly ash recovered after thermal treatment despite the fact that the carbon content remains in the fly ash. Using oxygen and inert gas mixtures, the present invention shows that a thermal treatment to about 500 degrees C. also sharply decreases the surfactant adsorption of the recovered fly ash even though most of the carbon remains intact. Also, thermal treatment to about 800 degrees C. under these same oxidative conditions shows a sharp decrease in surfactant adsorption of the recovered fly ash due to the fact that the carbon has been removed. This experiment simulates the various "carbon burnout" methods and is not a claim in this method. The present invention provides a thermal method of deactivating high carbon fly ash toward adsorption of AEAs while retaining the fly ash carbon. The fly ash can be used, for example, as a partial Portland cement replacement in air-entrained concrete, in conductive and other concretes, and for other applications.

  5. Mosquito and filth fly control in desert and temperate environments with a synergized pesticide mister and barrier treatment

    Science.gov (United States)

    U.S. military operations face significant negative impacts on mission readiness from disease-vector and nuisance filth flies, mosquitoes, and sand flies. Through the Deployed War Fighter Protection Program (DWFP) we previously developed small scale 9 ft by 3 ft pesticide-treated perimeters enhanced ...

  6. Lund Sand No 0

    DEFF Research Database (Denmark)

    Ibsen, Lars Bo; Jakobsen, Finn Rosendal

    During the last 15 years the Geotechnical Engineering Group (GEG) at Aalborg University has performed triaxial tests with a sand called Lund No 0. Lund No 0 is a graded sand from a gravel pit near Horsens in Denmark. For the classification of the sand the following tests have been performed: Sieve...... test, Grain density, ds, Maximum, emax, and minimum, emin, void ratio. The strength parameters of Lund No 0 are detennined by some drained and undrained triaxial tests in the Danish Triaxial Cell. The Danish Triaxial Cell prescribes smooth pressure heads and specimens with equal height and diameter....... Four series with Id equal to 0.92, 0.87 0.76 and 0.55 have been performed....

  7. UK Frac Sand Resources

    OpenAIRE

    Mitchell, C J

    2015-01-01

    Although still just a glimmer in the gas man’s eye, the prospect of shale hydrocarbon (oil and gas) development in the UK has many companies thinking about the industrial minerals it will require. Chief amongst these is silica sand which is used as a ‘proppant’ in the hydraulic fracturing, or ‘fracking’, of shales to help release the gas. The UK has large resources of sand and sandstone, of which only a small proportion have the necessary technical properties that classify them as ‘silica san...

  8. Suspension mechanism and application of sand-suspended slurry for coalmine fire prevention

    Institute of Scientific and Technical Information of China (English)

    Xu Yongliang; Wang Lanyun; Chu Tingxiang; Liang Donglin

    2014-01-01

    North and west China has abundant coal resources, however, such resources make these regions prone to serious mine fire disasters. Although the copious sand and fly ash resources found in these areas can be used as fire-fighting materials, conventional grouting is expensive because of water shortage and loess particles. A new compound material (i.e., a sand-suspended colloid), which comprises a mineral inorganic gel and an organic polymer, is developed in the current study to improve the quality of sand injection and reduce water wastage when grouting. The new material can steadily suspend the sand, through the addi-tion of a small amount of colloid yielding steady sand-suspended slurry. The process of producing the slurry is convenient and quick, overcoming the shortage of sand-suspending thickeners which need heat and are difficult to produce. The space work model based on the theory of the double-electric layer is established to study the suspended mechanism of the solid particles in the sand-suspended colloid. The dispersion effect of the sand-suspended colloid is demonstrated by the incorporation of the electro-static effect by the double-electric layer and the steric hindrance effect on the sand particles, ensuring the stability of the colloid system and the steady suspension of sand particles in the sand-suspended colloid. Mechanical analysis indicates that the sand is suspended steadily under the condition that the rock sand particles stress on the lower part of the fluid is less than the yield stress of the colloid. Finally, the fire-prevention technology of sand suspension was applied and tested in the Daliuta Coal Mine, achieving suc-cessful results.

  9. Building with Sand

    Science.gov (United States)

    Ashbrook, Peggy

    2010-01-01

    Children playing in damp sand invariably try to make a tower or a tunnel. By providing experiences with a variety of materials, alone and together, teachers set up the conditions for children to learn through their senses and ensure that a class approaches a topic with a common set of experiences to build on. Learning about the properties of…

  10. Speleothems and Sand Castles

    Science.gov (United States)

    Hance, Trevor; Befus, Kevin

    2015-01-01

    The idea of building sand castles evokes images of lazy summer days at the beach, listening to waves crash, enjoying salty breezes, and just unplugging for a while to let our inner child explore the wonderful natural toys beneath our feet. The idea of exploring caves might evoke feelings and images of claustrophobia or pioneers and Native…

  11. X-Ray Diffraction and SEM Investigation of Solidification/ Stabilization of Nickel and Chromium Using Fly ash

    Directory of Open Access Journals (Sweden)

    Ranjana A. Patil

    2011-01-01

    Full Text Available The main thrust of the paper is mechanism of immobilization of nickel(Ni and chromium(Cr metal sludge by solidification/stabilization using lime fly ash and sand (LFAS. The mineralogy of fly ash used for the study has been determined on the basis of x- ray diffraction analysis (XRD. Attempts have been made to investigate the consequences of interaction of heavy metal ion with constituents of lime fly ash sand composite on the basis of XRD studies and scanning electron microscopy (SEM, except chromium.

  12. Erosion phenomena in sand moulds

    Directory of Open Access Journals (Sweden)

    A. Chojecki

    2008-03-01

    Full Text Available Authors studicd the erosion phcnorncna in sand moulds pured with cast iron. Thc study comprises an evaluation of erosionresistance of thc three sands: grccn sand. sand bondcd with inorganic or organic bindcr. It was concluded that thc most resistant is [heclassic green sand with thc addition of 5 B coal dust. Resistance of the sand with organic binder is generally weak and dcvnds onkind of used raisin. Spccinl nztcntion was paid to the sands with no organic bindcr watcr glass and phospha~c. It was Sound that thcirrcsistance depends on dehydratation conditions. When the mould is stored in law humidity of atmosphcrc the very strong crosion canbe expected. It rcsul ts hrn thc micro fractures in the bridges of binders, joining the grains of the sable. This phcnomcna facilitates thetearing away of fragments of sand [tom the surface

  13. New uses of gas in Canada : oil sands gas demand

    Energy Technology Data Exchange (ETDEWEB)

    Camarta, N. [Shell Canada Ltd., Calgary, AB (Canada)

    2003-07-01

    The relationship between the price of natural gas and the development of oil sands in northern Alberta was discussed with reference to Shell Canada's Athabasca Oil Sands Project (AOSP), its resource base and plans for future expansion. Several graphs were presented, depicting world scale resources, Canadian oil production, and the North American oil market. Graphs depicting future projections for oil sands natural gas demand and cogeneration capacity showed that the trend for both demand and capacity is steadily increasing. The AOSP is a large high quality reserve with low overburden. The project utilizes advanced bitumen clean-up technology and the site is equipped with a highly integrated refinery that exploits infrastructure synergies. Some of the risk factors associated with oil sand development were described as being capital costs, operating costs, commodity prices, labour supply, and the Kyoto Protocol. 24 figs.

  14. Ever Fly a Tetrahedron?

    Science.gov (United States)

    King, Kenneth

    2004-01-01

    Few things capture the spirit of spring like flying a kite. Watching a kite dance and sail across a cloud spotted sky is not only a visually appealing experience it also provides a foundation for studies in science and mathematics. Put simply, a kite is an airfoil surface that flies when the forces of lift and thrust are greater than the forces of…

  15. On Pluvial Compaction of Sand

    DEFF Research Database (Denmark)

    Jacobsen, Moust

    At the Institute of Civil Engineering in Aalborg model tests on dry sand specimens have been carried out during the last five years. To reduce deviations in test results, the sand laying technique has been carefully studied, and the sand mass spreader constructed. Preliminary results have been...

  16. Sand hazards on tourist beaches.

    Science.gov (United States)

    Heggie, Travis W

    2013-01-01

    Visiting the beach is a popular tourist activity worldwide. Unfortunately, the beach environment is abundant with hazards and potential danger to the unsuspecting tourist. While the traditional focus of beach safety has been water safety oriented, there is growing concern about the risks posed by the sand environment on beaches. This study reports on the death and near death experience of eight tourists in the collapse of sand holes, sand dunes, and sand tunnels. Each incident occurred suddenly and the complete burial in sand directly contributed to the victims injury or death in each case report.

  17. Experimental study of optimal self compacting concrete with spent foundry sand as partial replacement for M-sand using Taguchi approach

    Science.gov (United States)

    Nirmala, D. B.; Raviraj, S.

    2016-06-01

    This paper presents the application of Taguchi approach to obtain optimal mix proportion for Self Compacting Concrete (SCC) containing spent foundry sand and M-sand. Spent foundry sand is used as a partial replacement for M-sand. The SCC mix has seven control factors namely, Coarse aggregate, M-sand with Spent Foundry sand, Cement, Fly ash, Water, Super plasticizer and Viscosity modifying agent. Modified Nan Su method is used to proportion the initial SCC mix. L18 (21×37) Orthogonal Arrays (OA) with the seven control factors having 3 levels is used in Taguchi approach which resulted in 18 SCC mix proportions. All mixtures are extensively tested both in fresh and hardened states to verify whether they meet the practical and technical requirements of SCC. The quality characteristics considering "Nominal the better" situation is applied to the test results to arrive at the optimal SCC mix proportion. Test results indicate that the optimal mix satisfies the requirements of fresh and hardened properties of SCC. The study reveals the feasibility of using spent foundry sand as a partial replacement of M-sand in SCC and also that Taguchi method is a reliable tool to arrive at optimal mix proportion of SCC.

  18. PROCESSING OF MONAZITE SAND

    Science.gov (United States)

    Calkins, G.D.; Bohlmann, E.G.

    1957-12-01

    A process for the recovery of thorium, uranium, and rare earths from monazite sands is presented. The sands are first digested and dissolved in concentrated NaOH, and the solution is then diluted causing precipitation of uranium, thorium and rare earth hydroxides. The precipitate is collected and dissolved in HCl, and the pH of this solution is adjusted to about 6, precipitating the hydroxides of thorium and uranium but leaving the rare earths in solution. The rare earths are then separated from the solution by precipitation at a still higher pH. The thorium and uranium containing precipitate is redissolved in HNO/sub 3/ and the two elements are separated by extraction into tributyl phosphate and back extraction with a weakly acidic solution to remove the thorium.

  19. Moving sand dunes

    CERN Document Server

    Sparavigna, Amelia Carolina

    2011-01-01

    In several desert areas, the slow motion of sand dunes can be a challenge for modern human activities and a threat for the survival of ancient places or archaeological sites. However, several methods exist for surveying the dune fields and estimate their migration rate. Among these methods, the use of satellite images, in particular of those freely available on the World Wide Web, is a convenient resource for the planning of future human settlements and activities.

  20. Booming Sand Dunes

    Science.gov (United States)

    Vriend, Nathalie

    "Booming" sand dunes are able to produce low-frequency sound that resembles a pure note from a music instrument. The sound has a dominant audible frequency (70-105 Hz) and several higher harmonics and may be heard from far distances away. A natural or induced avalanche from a slip face of the booming dune triggers the emission that may last for several minutes. There are various references in travel literature to the phenomenon, but to date no scientific explanation covered all field observations. This thesis introduces a new physical model that describes the phenomenon of booming dunes. The waveguide model explains the selection of the booming frequency and the amplification of the sound in terms of constructive interference in a confined geometry. The frequency of the booming is a direct function of the dimensions and velocities in the waveguide. The higher harmonics are related to the higher modes of propagation in the waveguide. The experimental validation includes quantitative field research at the booming dunes of the Mojave Desert and Death Valley National Park. Microphone and geophone recordings of the acoustic and seismic emission show a variation of booming frequency in space and time. The analysis of the sensor data quantifies wave propagation characteristics such as speed, dispersion, and nonlinear effects and allows the distinction between the source mechanism of the booming and the booming itself. The migration of sand dunes results from a complicated interplay between dune building, wind regime, and precipitation. The morphological and morphodynamical characteristics of two field locations are analyzed with various geophysical techniques. Ground-penetrating radar images the subsurface structure of the dunes and reveal a natural, internal layering that is directly related to the history of dune migration. The seismic velocity increases abruptly with depth and gradually increases with downhill position due to compaction. Sand sampling shows local

  1. Significance and survival of Enterococci during the house fly development.

    Science.gov (United States)

    Ghosh, Anuradha; Akhtar, Mastura; Holderman, Chris; Zurek, Ludek

    2014-01-01

    House flies are among the most important nonbiting insect pests of medical and veterinary importance. Larvae develop in decaying organic substrates and their survival strictly depends on an active microbial community. House flies have been implicated in the ecology and transmission of enterococci, including multi-antibiotic-resistant and virulent strains of Enterococcus faecalis. In this study, eight American Type Culture Collection type strains of enterococci including Enterococcus avium, Enterococcus casseliflavus, Enterococcus durans, Enterococcus hirae, Enterococcus mundtii, Enterococcus gallinarum, Enterococcusfaecalis, and Enterococcusfaecium were evaluated for their significance in the development of house flies from eggs to adults in bacterial feeding assays. Furthermore, the bacterial colonization of the gut of teneral flies as well as the importance of several virulence traits of E. faecalis in larval mortality was assessed. Overall survival of house flies (egg to adult) was significantly higher when grown with typically nonpathogenic enterococcal species such as E. hirae (76.0% survival), E. durans (64.0%), and E. avium (64.0%) compared with that with clinically important species E. faecalis (24.0%) and E. faecium (36.0%). However, no significant differences in survival of house fly larvae were detected when grown with E. faecalis strains carrying various virulence traits, including isogenic mutants of the human clinical isolate E. faecalis V583 with in-frame deletions of gelatinase, serine protease, and capsular polysaccharide serotype C. Enterococci were commonly detected in fly puparia (range: 75-100%; concentration: 103-105 CFU/puparium);however, the prevalence of enterococci in teneral flies varied greatly: from 25.0 (E. casseliflavus) to 89.5% (E. hirae). In conclusion, depending on the species, enterococci variably support house fly larval development and colonize the gut of teneral adults. The human pathogenic species, E. faecalis and E. faecium

  2. Recyclability of Concrete Pavement Incorporating High Volume of Fly Ash

    Directory of Open Access Journals (Sweden)

    Isamu Yoshitake

    2015-08-01

    Full Text Available Recyclable concrete pavement was made from fly ash and crushed limestone sand and gravel as aggregates so that the concrete pavement could be recycled to raw materials for cement production. With the aim to use as much fly ash as possible for the sustainable development of society, while achieving adequate strength development, pavement concrete having a cement-replacement ratio of 40% by mass was experimentally investigated, focusing on the strength development at an early age. Limestone powder was added to improve the early strength; flexural strength at two days reached 3.5 MPa, the minimum strength for traffic service in Japan. The matured fly ash concrete made with a cement content of 200 kg/m3 achieved a flexural strength almost equal to that of the control concrete without fly ash. Additionally, Portland cement made from the tested fly ash concrete was tested to confirm recyclability, with the cement quality meeting the Japanese classification of ordinary Portland cement. Limestone-based recyclable fly ash concrete pavement is, thus, a preferred material in terms of sustainability.

  3. Sediment mathematical model for sand ridges and sand waves

    Institute of Scientific and Technical Information of China (English)

    LI Daming; WANG Xiao; WANG Xin; LI Yangyang

    2016-01-01

    A new theoretical model is formulated to describe internal movement mechanisms of the sand ridges and sand waves based on the momentum equation of a solid-liquid two-phase flow under a shear flow. Coupling this equation with two-dimensional shallow water equations and wave reflection-diffraction equation of mild slope, a two-dimensional coupling model is established and a validation is carried out by observed hydrogeology, tides, waves and sediment. The numerical results are compared with available observations. Satisfactory agreements are achieved. This coupling model is then applied to the Dongfang 1-1 Gas Field area to quantitatively predict the movement and evolution of submarine sand ridges and sand waves. As a result, it is found that the sand ridges and sand waves movement distance increases year by year, but the development trend is stable.

  4. Flying in North America

    Directory of Open Access Journals (Sweden)

    Jaromír Procházka

    2013-01-01

    Full Text Available Flying all over the world is very challenging and demanding. Although ICAO is covering every specific detail by rules, there are some personal experiences which cannot be substituted. Some of them are point out in the article.

  5. Phlebotominae (Diptera: Psychodidae de Lagoas, município de Buriticupu, Amazônia Maranhense. I - Riqueza e abundância relativa das espécies em área de colonização recente Sand flies (Diptera: Psychodidae of Lagoas, municipal district of Buriticupu, Amazonia of Maranhão. I - Richness and relative abundance of the species in area of recent colonisation

    Directory of Open Access Journals (Sweden)

    José Manuel Macário Rebêlo

    2000-02-01

    Full Text Available Este estudo determinou a riqueza de espécies e a abundância relativa dos flebotomíneos da comunidade de Lagoas, em Buriticupu, na Amazônia Maranhense. O estudo consistiu na captura de formas adultas com auxílio de armadilhas luminosas tipo CDC e armadilha de Shannon, das 18 às 6 horas, uma vez por mês, de dezembro/95 a janeiro/97, em ambiente florestal e extraflorestal (peri e intradomicílios. No total, capturou-se 9.392 espécimens (4.302 machos e 5.090 fêmeas distribuídos em 38 espécies (1 Brumptomyia e 37 Lutzomyia. A riqueza e abundância de espécies foram maiores na mata, seguida do peri e intradomicílio. Na mata, as espécies mais freqüentes foram Lutzomyia whitmani (64,9%, L. migonei (27% e L. serrana (3,6%. No peridomicílio, predominaram L. evandroi (55,4%, L. whitmani (33,4% e L. migonei (6,4% e no intra, L. evandroi (97,9%. O predomínio no ambiente silvestre resulta das potencialidades ainda encontradas nas glebas remanescentes da floresta tão explorada pelas atividades madeireira e agropecuária. Por outro lado, a peridomiciliação de 7,7% das espécies reverteu-se de grande importância epidemiológica, haja visto a existência de pacientes com leishmanioses que julgam ter adquirido a infecção nas proximidades de suas habitações.In this study the diversity of the species and relative abundance of the sand flies in the Amazonian community of Lagoas, in Buriticupu, Maranhão State, was determined. The study consisted of adult sandflies captured with CD light-traps, Shannon-trap and manual aspiration tube, between 18 PM and 6 AM, once a month, from December/95 to January/97, in a forest fragment and in the domestic environment (peri and intra. In all, 9,393 specimens were captured (4,302 males and 5,140 females distributed among 38 species (1 Brumptomyia and 37 Lutzomyia. The diversity and abundance of species was higher in the forest, followed by the peri and intra. The predominance in the wild ambient is a

  6. Elastic properties of fly ash-stabilized mixes

    Directory of Open Access Journals (Sweden)

    Sanja Dimter

    2015-12-01

    Full Text Available Stabilized mixes are used in the construction of bearing layers in asphalt and concrete pavement structures. Two nondestructive methods: resonant frequency method and ultrasonic pulse velocity method, were used for estimation of elastic properties of fly ash–stabilized mixes. Stabilized mixes were designed containing sand from the river Drava and binder composed of different share of cement and fly ash. The aim of the research was to analyze the relationship between the dynamic modulus of elasticity determined by different nondestructive methods. Data showed that average value of elasticity modulus obtained by the ultrasound velocity method is lower than the values of elasticity modulus obtained by resonant frequency method. For further analysis and enhanced discussion of elastic properties of fly ash stabilized mixes, see Dimter et al. [1].

  7. The Fly Printer - Extended

    DEFF Research Database (Denmark)

    Beloff, Laura; Klaus, Malena

    2016-01-01

    Artist talk / Work-in-progress What is the purpose of a machine or an artifact, like the Fly Printer, that is dislocated, that produces images that have no meaning, no instrumentality, that depict nothing in the world? The biological and the cultural are reunited in this apparatus as a possibilit...... the results. The extended version of the Fly Printer containing the technological perception and DNNs is a collaboration between Laura Beloff and Malene Theres Klaus...

  8. Process parameter optimization for fly ash brick by Taguchi method

    Energy Technology Data Exchange (ETDEWEB)

    Prabir Kumar Chaulia; Reeta Das [Central Mechanical Engineering Research Institute, Durgapur (India)

    2008-04-15

    This paper presents the results of an experimental investigation carried out to optimize the mix proportions of the fly ash brick by Taguchi method of parameter design. The experiments have been designed using an L9 orthogonal array with four factors and three levels each. Small quantity of cement has been mixed as binding materials. Both cement and the fly ash used are indicated as binding material and water binder ratio has been considered as one of the control factors. So the effects of water/binder ratio, fly ash, coarse sand, and stone dust on the performance characteristic are analyzed using signal-to-noise ratios and mean response data. According to the results, water/binder ratio and stone dust play the significant role on the compressive strength of the brick. Furthermore, the estimated optimum values of the process parameters are corresponding to water/binder ratio of 0.4, fly ash of 39%, coarse sand of 24% and stone dust of 30%. The mean value of optimal strength is predicted as 166.22 kg.cm{sup -2} with a tolerance of 10.97 kg.cm{sup -2}. The confirmatory experimental result obtained for the optimum conditions is 160.17 kg.cm{sup -2}. 13 refs., 3 figs., 7 tabs.

  9. Sand Storms Trigger Alarm

    Institute of Scientific and Technical Information of China (English)

    LI LI

    2010-01-01

    @@ After an unusually humid winter with at least 10 snowfalls in Beijing, a severe andstorm blown by strong winds bringing with it thousands of tons of desert sand took many residents of the city by surprise.On the morning of March 20, Beijingers woke up to see clouds of yellow dust in the air and a sky that was an ominous orange in color.The loose soil and dust that had traveled htmdreds of miles from deserts in Mongolia and China's northwest blanketed Beijing's streets, covering parked vehicles, bikes, roofs and even plant life,as well as making its way into people's homes.

  10. Fortune Cookie Sand Dunes

    Science.gov (United States)

    2003-01-01

    MGS MOC Release No. MOC2-432, 25 July 2003This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a field of small barchan sand dunes in the north polar region near 71.7oN, 51.3oW. Some of them are shaped like fortune cookies. The message these dunes provide: winds blow through this region from the lower right toward the upper left. The steep slip face slopes of these dunes, which point toward the upper left, indicate the wind direction. The scene is illuminated by sunlight from the upper right. The image is 3 km (1.9 mi) wide.

  11. Sand dollar sites orogenesis

    Science.gov (United States)

    Amos, Dee

    2013-04-01

    The determinology of the humble sand dollars habitat changing from inception to the drastic evolution of the zone to that of present day. Into the cauldron along the southern Californian 'ring of fire' lithosphere are evidence of geosynclinals areas, metasedimentary rock formations and hydrothermal activity. The explanation begins with 'Theia' and the Moon's formation, battles with cometary impacts, glacial ages, epochs with evolutionary bottlenecks and plate tectonics. Fully illustrated the lecture includes localised diagrams and figures with actual subject photographic examples of plutonic, granitic, jade and peridodite. Finally, the origins of the materials used in the lecture are revealed for prosecution by future students and the enjoyment of interested parties in general.

  12. Compressive behavior of fine sand.

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Bradley E. (Air Force Research Laboratory, Eglin, FL); Kabir, Md. E. (Purdue University, West Lafayette, IN); Song, Bo; Chen, Wayne (Purdue University, West Lafayette, IN)

    2010-04-01

    The compressive mechanical response of fine sand is experimentally investigated. The strain rate, initial density, stress state, and moisture level are systematically varied. A Kolsky bar was modified to obtain uniaxial and triaxial compressive response at high strain rates. A controlled loading pulse allows the specimen to acquire stress equilibrium and constant strain-rates. The results show that the compressive response of the fine sand is not sensitive to strain rate under the loading conditions in this study, but significantly dependent on the moisture content, initial density and lateral confinement. Partially saturated sand is more compliant than dry sand. Similar trends were reported in the quasi-static regime for experiments conducted at comparable specimen conditions. The sand becomes stiffer as initial density and/or confinement pressure increases. The sand particle size become smaller after hydrostatic pressure and further smaller after dynamic axial loading.

  13. Triaxial tests in Fontainebleau sand

    DEFF Research Database (Denmark)

    Latini, Chiara; Zania, Varvara

    2016-01-01

    The purpose of this internal report is to examine the influence of relative density on the strength and deformation characteristics of Fontainebleau sand. Compression triaxial tests were performed on saturated sand samples with different densities and initial confining pressure. Note that the tes......The purpose of this internal report is to examine the influence of relative density on the strength and deformation characteristics of Fontainebleau sand. Compression triaxial tests were performed on saturated sand samples with different densities and initial confining pressure. Note...... that the testing procedure and the data processing were carried out according to the specifications of ETCS-F1.97....

  14. Influence of Biofuel Combustion Fly Ash on the Properties of Concrete

    Directory of Open Access Journals (Sweden)

    Nagrockienė Džigita

    2015-12-01

    Full Text Available Cement as the binding agent in the production of concrete can be replaced with active mineral admixtures. Biofuel combustion fly ash is one of such admixtures. Materials used for the study include Portland cement CEM I 42.5 R, sand of 0/4 fraction, gravel of 4/16 fraction, biofuel fly ash, superplasticizer, and water. Six compositions of concrete were designed by replacing 0 %, 5 %, 10 %, 15 % 20 %, and 25 % of cement with biofuel fly ash. The article analyses the effect of biofuel fly ash content on the properties of concrete. The tests revealed that the increase of biofuel fly ash content up to 20 % increases concrete density and compressive strength after 7 and 28 days of curing and decreases water absorption, with corrected water content by using plasticizing admixture. It has been found that concrete where 20 % of cement is replaced by biofuel ash has higher frost resistance.

  15. A sand wave simulation model

    NARCIS (Netherlands)

    Nemeth, A.A.; Hulscher, S.J.M.H.; Damme, van R.M.J.

    2003-01-01

    Sand waves form a prominent regular pattern in the offshore seabeds of sandy shallow seas. A two dimensional vertical (2DV) flow and morphological numerical model describing the behaviour of these sand waves has been developed. The model contains the 2DV shallow water equations, with a free water su

  16. Sand swimming lizard: sandfish

    CERN Document Server

    Maladen, Ryan D; Kamor, Adam; Goldman, Daniel I

    2009-01-01

    We use high-speed x-ray imaging to reveal how a small (~10cm) desert dwelling lizard, the sandfish (Scincus scincus), swims within a granular medium [1]. On the surface, the lizard uses a standard diagonal gait, but once below the surface, the organism no longer uses limbs for propulsion. Instead it propagates a large amplitude single period sinusoidal traveling wave down its body and tail to propel itself at speeds up to ~1.5 body-length/sec. Motivated by these experiments we study a numerical model of the sandfish as it swims within a validated soft sphere Molecular Dynamics granular media simulation. We use this model as a tool to understand dynamics like flow fields and forces generated as the animal swims within the granular media. [1] Maladen, R.D. and Ding, Y. and Li, C. and Goldman, D.I., Undulatory Swimming in Sand: Subsurface Locomotion of the Sandfish Lizard, Science, 325, 314, 2009

  17. Use of coal ash for enhancing biocrust development in stabilizing sand dunes

    Science.gov (United States)

    Zaady, Eli; Katra, Itzhak; Sarig, Shlomo

    2015-04-01

    In dryland environments, biocrusts are considered ecosystem engineers since they play significant roles in ecosystem processes. In the successional pathway of crust communities, the new areas are colonized after disturbance by pioneers such as filamentous cyanobacteria - Microcoleus spp. This stage is followed by colonization of green algae, mosses, and lichens. Aggregation of soil granules is caused by metabolic polysaccharides secreted by cyanobacteria and green algae, gluing the soil particles to form the crust layer. It was suggested that incorporating dust into the biocrusts encourages the growth of cyanobacteria, leading to a strengthening of the biocrusts' cohesion. Moreover, biocrusts cover a larger portion of the surface when the soil contains finer particles, and it was observed that at least 4-5% of clay and silt is required to support a measurable biocrust. While natural and undisturbed sand dunes are generally stabilized by biocrusts in the north-western Negev desert, stabilization of disturbed and movable sand dunes is one of the main problems in this desertified land, as in vast areas in the world. Daily breezes and seasonal wind storms transport sand particles to populated and agricultural areas causing damages to field crops and livelihood. Moving sand dunes consist of relatively coarse grains (250-2000 μm) with a low percent of clay and silt. This phenomenon negatively affects cyanobacterial colonization rate, even in relatively wet desert areas (100-250 mm rainfalls). In order to face the problem it was suggested to enrich the dune surface by using coal fly-ash. The research was conducted in two stages: first, examining the feasibility in Petri-dishes in laboratory conditions and in Experimental Aeolian Greenhouse conditions. The results showed that adding coal fly-ash and biocrust inoculum increased aggregate stability, penetration resistance and shear strength, as opposed to the control-sand plot. Using mobile wind-tunnel simulations, sand

  18. 2010 oil sands performance report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-01

    With the depletion of traditional energy resources and the rising demand for energy, oil sands have become an important energy resource for meeting energy needs. Oil sands are a mixture of water, sand, clay and bitumen which is recovered either through open pit mining or in situ drilling techniques. The bitumen is then converted into syncrude or sold to refineries for the production of gasoline, diesel or other products. Shell has oil sands operations in Alberta and the aim of this report is to present its 2010 performance in terms of CO2, water, tailings, land, and reclamation and engagement. This document covers several of Shell's operations in the Muskeg River and Jackpine mines, Scotford upgrader, Peace River, Orion, Seal, Cliffdale and Chipmunk. It provides useful information on Shell's oil sands performance to governments, environmental groups, First Nations, local communities and the public.

  19. ANALYSIS OF FLYING BIKE

    OpenAIRE

    Momin Irfan Ali Nasir Husain *1, Shah mohd. Rafique rahmatullah *2, Naumanulhaq Barkatullah Shaikh *3, Khatib Mohd. Azimuddin Najimuddin *4, Ansari Mohammad Naasir Shamsudduha *5, Ansari Mohammad Parvez Abdul Qayyum*6, Momin Mohammad Rayyan Mohammad Shakeel*7, Ansari Peer Mohammed Munna *8, Prof. Mohd. Musharraf Aamir

    2016-01-01

    Flying Bike vertical take-off and landing (VTOL) type machine which also follows Newton’s third law. It is thought of as a conventional type of aircraft with special features added to enable it to rise vertically during take-off and to land from a vertical descent.  It flies with two propellers located at front and back side. These propellers are having hovering abilities. The vehicle is controlled by tilting the propellers by using lever mechanism. Rotation is carried out by diffe...

  20. Sand harm in taklimakan Desert highway and sand control

    Institute of Scientific and Technical Information of China (English)

    HANZhiwen; WANGTao; SUNQingwei; DONGZhibao; WANGXunming

    2003-01-01

    Reputed as a wonderful achievement of the world’s highway construction history,the Taklimakan Desert highway is nor facing serious sand drift encroachment problems due to its 447-km-long passage of sand sea consisting of crescent dunes,barchan chains,compound transverse dune ridges and complex megadunes.To solve some technical problems in the protection of the highway from sang drift encroachment,desert experts have been conducting the theoretical and applied studies on sand movement laws;causes,severities and time-space differentiation of sand drift damages;and control ways including mechanical,chemical and biological measures.In this paper the authors give an overall summry on the research contents and recent progress in the control of sand drift damages in China and hold that the theoretical researc results and practices in the prevention of sand drift encroachment on the cross-desert highway represnt a breakthrough and has an cpoch-making significance.Since the construction of protective forest along the cross-desert highway requires large amount of ground water,what will be its environmental consequence and whether it can effectively halt sand drift encroachment on the highway forever are the questions to be studied urgently.

  1. Non-standard tests for process control in chemically bonded sands

    Directory of Open Access Journals (Sweden)

    S. Ramrattan

    2016-01-01

    Full Text Available Chemically bonded sand cores and molds are more commonly referred to as precision sand systems in the high production automotive powertrain sector. Their behavior in contact with molten metal can lead to casting defects. Consequently, the interaction is of great interest and an important part of metal casting technology. The American Foundry Society (AFS sand testing is based on physical, mechanical, thermal and chemical properties of the sand system. Foundry engineers have long known that certain AFS sand tests provide limited information regarding control of molding and casting quality. The inadequacy is due to the fact that sand casting processes are inherently thermo-mechanical, thermo-chemical and thermo-physical. Non-standard foundry sand testing has proven useful for laboratory measurement of these characteristics in foundry sand using a disc-shaped specimen. Similarly, the equivalent disc-shaped specimens are used for casting trials. In order to accomplish near-net-shape casting with minimal defects, it is necessary to understand both the properties of the sand system, as well as the interface of molten metal when different binders, additives and/or refractory coatings are used. The methodology for the following non-standard chemically bonded sand tests is described: (1 disc transverse; (2 impact; (3 modified permeability; (4 abrasion; (5 thermal distortion; (6 quick loss on ignition. The data related to the non-standard sand tests were analyzed and interpreted. The test results indicate that there is relatively lower test-to-test variability with the disc-shaped specimens. The non-standard tests were able to discriminate between the chemically bonded polyurethane cold box sand specimens. Further studies should be conducted on various other sand and binder systems as well as on different specimen thicknesses.

  2. Kite-Flying Fun

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    China’s kite capital welcomes flying enthusiasts from across the world to its annual carnival Tens of thousands of kite enthusiast from all over the world gathered under the growing swarm of brightly colored kites. Some of the floating and billowing forms had been fashioned into

  3. Sand engine quells the coast's hunger for sand

    NARCIS (Netherlands)

    Van Dijk, T.

    2012-01-01

    An artificial peninsula at Ter Heijde is designed to feed the coast with sediment. Scientists are investigating whether this kind of sand engine could be the Netherlands’ answer to rising sea levels.

  4. Research on Application of Manufactured Sand and Manufactured Sand Concrete%机制砂及机制砂混凝土应用与探讨

    Institute of Scientific and Technical Information of China (English)

    杨声检

    2015-01-01

    为了保护环境并且节约成本,河砂的开采必须得到遏制,取而代之的机制砂生产已迫在眉睫。对机制砂的主要成分以及机制砂混凝土的性能进行了介绍。在多条机制砂生产线实地考察和调研的基础上,重点采用河砂以及机制砂试配了 C30水下桩基混凝土与 C25隧道二衬防水混凝土,得到了机制砂的物理性能以及两种混凝土的性能指标,试验同时考虑了掺粉煤灰的影响。试验结果表明,机制砂的物理性能以及试配的两种混凝土的性能均达到同等级河砂混凝土的性能标准,适用于水下桩基混凝土与隧道二衬防水混凝土的应用。%With the aims of environmental protection and cost-cutting,exploitation of the river sand must be stopped and the manufacture of manufactured sand is becoming urgently needed.In this article,the main compo-nent of the manufactured sand and the mechanical performance of manufactured sand concrete have been intro-duced.On the basis of the investigation on several production lines of manufactured sand,emphasis is put on the experiment of C30 underwater concrete and C25 tunnel lining waterproof concrete by manufactured sand and river sand respectively,the physical property of the manufactured sand and the performance of concrete by these two kinds of sand have been obtained,and the effect of fly ash has also been taken into account in the experiments. The results show that both the physical property of the manufactured sand and the performance of manufactured sand concrete meet the requirements as the river sand concrete,and the manufactured sand can be used in the manufacture of underwater pile foundation concrete and tunnel lining waterproof concrete.

  5. Effect of fly ash calcination in geopolymer synthesis

    Science.gov (United States)

    Samadhi, Tjokorde Walmiki; Jatiningrum, Mirna; Arisiani, Gresia

    2015-12-01

    Geopolymer, a largely amorphous class of inorganic polymer consisting of aluminosilicate repeat units, is an environmentally attractive engineering material due to its ability to consume aluminosilicate waste as raw materials. This work studies the effect of the calcination temperature of a coal fly ash generated by a low-efficiency boiler on the mechanical strength of geopolymer mortar synthesized using a mixture of the fly ash, potassium hydroxide as the alkali activator, and locally available sand as the filler aggregate. The calcination temperature is varied between 500-700 °C, with a calcination period of 2 hours in an electric furnace. Two sand samples with different particle size distributions are used. The key response variable is the compressive strength at room temperature, measured after curing at 80 °C for 7 and 14 days. Uncalcined ash, with a carbon content of approximately 31.0%, is not amenable for geopolymer synthesis. Analysis of experimental data using the ANOVA method for general factorial design identifies significant main effects for all three experimental variables. Two-way interactions are significant, except that between sand type and curing period. Higher calcination temperature significantly improves the strength of the mortar. However, the strength of the obtained geopolymer mortars are still significantly lower than that of ordinary Portland cement mortar.

  6. Use of fly ash for the production of mineral wool; Utilisation de cendres volantes pour la production de laine minerale

    Energy Technology Data Exchange (ETDEWEB)

    Simovic, I. [Institut des Mines (Yugoslavia); Micevic, Z. [Energoprojekt, Belgrade (Yugoslavia); Djekic, S. [EPS, Belgrade (Yugoslavia)

    2001-03-01

    Yugoslavian power plants generate about 7.5 Mt of fly ash per year. Today, only 15% of this ash is used by different industries. A technology has been developed which allows to produce mineral wool from fly ash and quartz sand. Physical, chemical and mineralogical studies have confirmed the good quality of the fibers in terms of homogeneity and structure. Abstract only. (J.S.)

  7. An annotated checklist of the horse flies, deer flies, and yellow flies (Diptera: Tabanidae) of Florida

    Science.gov (United States)

    The family Tabanidae includes the horse flies, deer flies, and yellow flies and is considered a significant pest of livestock throughout the United States, including Florida. Tabanids can easily become a major pest of man, especially salt marsh species which are known to readily feed on humans and o...

  8. Reclaimability of the spent sand mixture – sand with bentonite – sand with furfuryl resin

    Directory of Open Access Journals (Sweden)

    J. Dańko

    2011-04-01

    Full Text Available Introduction of new binding materials and new technologies of their hardening in casting moulds and cores production requires theapplication of reclamation methods adequate to their properties as well as special devices realizing tasks. The spent sands circulationsystem containing the same kind of moulding and core sands is optimal from the point of view of the expected reclamation results.However, in the face of a significant variability of applied technologies and related to them various reclamation methods, the need - of theobtained reclamation products assessment on the grounds of systematic criteria and uniform bases – arises, with a tendency of indicatingwhich criteria are the most important for the given sand system. The reclaimability results of the mixture of the spent moulding sand withGeko S bentonite and the spent core sand with the Kaltharz 404U resin hardened by acidic hardener 100 T3, are presented in the paper.Investigations were performed with regard to the estimation of an influence of core sands additions (10 –25% on the reclaimed materialquality. Dusts and clay content in the reclaim, its chemical reaction (pH and ignition loss were estimated. The verification of the reclaiminstrumental assessment was performed on the basis of the technological properties estimation of moulding sand with bentonite, where the reclaimed material was used as a matrix.

  9. Management recommendations: Sand Lake Complex

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document is a review of land management practices at the Sand Lake National Wildlife Refuge, by a land use specialist. Recommendations, time frame and...

  10. Flying Saucer? Aliens?

    Science.gov (United States)

    1961-01-01

    No, it's not a flying saucer, it is the domed top to a 70 foot long vacuum tank at the Lewis Research Center's Electric Propulsion Laboratory, Cleveland, Ohio. The three technicians shown here in protective clothing had just emerged from within the tank where they had been cleaning in the toxic mercury atmosphere, left after ion engine testing in the tank. Lewis has since been renamed the John H. Glenn Research Center.

  11. Myiasis with Lund's fly (Cordylobia rodhaini) in travelers.

    Science.gov (United States)

    Tamir, Jeremy; Haik, J; Schwartz, Eli

    2003-01-01

    Myiasis is an infestation of human tissue by the larvae of certain flies. There are many forms of myiasis, including localized furuncular myiasis, creeping dermal myiasis and wound and body cavity myiasis.1 Cordylobia anthropophaga (the Tumbu fly) and Dermatobia hominis (the human botfly) are the most common causes of myiasis in Africa and tropical America respectively. The genus Cordylobia also contains two less common species, C. ruandae and C. rodhaini. The usual hosts of C. rodhaini are various mammals (particularly rodents), and and humans are accidentally infested. Figure 1 shows the life cycle of C. rodhaini, which occurs over 55 to -67 days.3 The female fly deposits her eggs on dry sand polluted with the excrement of animals or on human clothing. In about 3 days, the larva is activated by the warm body of the host, hatches and invades the skin. As the larva matures, it induces a furuncular swelling. In 12 to -15 days, the larva reaches a length of about 23 mm, exits the skin and falls to the ground to pupate. The adult fly emerges in 23 to -26 days, and the life cycle resumes. In humans, the skin lesion starts as a red papule that gradually enlarges and develops into a furuncle. In the center of the lesion an opening forms, through which the larva breaths and discharges its serosanguinous feces. The lesion is associated with increasing pain until the larva exits the skin. The disease is usually uncomplicated and self-limiting.

  12. Disturbance of the inclined inserting-type sand fence to wind-sand flow fields and its sand control characteristics

    Science.gov (United States)

    Cheng, Jian-jun; Lei, Jia-qiang; Li, Sheng-yu; Wang, Hai-feng

    2016-06-01

    The inclined inserting-type sand fence is a novel sand retaining wall adopted along the Lanxin High-Speed Railway II in Xinjiang for controlling and blocking sand movement. To verify the effectiveness of the new fence structure for sand prevention, a wind tunnel test was used for flow field test simulation of the sand fence. The results indicate that the inclined inserting-type sand fence was able to deflect the flow of the sand and was able to easily form an upward slant acceleration zone on the leeward side of the sand fence. As shown by the percentage change in sand collection rates on the windward side and the leeward side of the sand fence, the sand flux per unit area at 4 m height in the slant upward direction increased on the leeward side of the inclined inserting-type sand fence. By comparing the flow fields, this site is an acceleration zone, which also reaffirms the correspondence of wind-sand flow fields with the spatial distribution characteristic of the wind-carried sand motion. The field sand collection data indicates that under the effects of the inclined inserting-type sand fence, the sandy air currents passing in front and behind the sand fence not only changed in quality, but the grain composition and particle size also significantly changed, suggesting that the inclined inserting-type sand fence has a sorting and filtering effect on the sandy air currents that passed through. The fence retained coarse particulates on the windward side and fine particulates within the shade of the wind on the leeward side.

  13. Sand fly captures with Disney traps in area of occurrence of Leishmania (Leishmania) amazonensis in the state of Mato Grosso do Sul, mid-western Brazil Capturas de flebotomíneos com armadilhas de Disney em área de ocorrência de Leishmania (Leishmania) amazonensis no estado de Mato Grosso do Sul, região Centro-Oeste do Brasil

    OpenAIRE

    Maria Elizabeth Cavalheiros Dorval; Tulia Peixoto Alves; Geucira Cristaldo; Hilda Carlos da Rocha; Murilo Andrade Alves; Elisa Teruya Oshiro; Alessandra Gutierrez de Oliveira; Reginaldo Peçanha Brazil; Eunice Aparecida Bianchi Galati; Rivaldo Venancio da Cunha

    2010-01-01

    INTRODUCTION: The work was conducted to study phlebotomine fauna (Diptera: Psychodidae) and aspects of American cutaneous leishmaniasis transmission in a forested area where Leishmania (Leishmania) amazonensis occurs, situated in the municipality of Bela Vista, State of Mato Grosso do Sul, Brazil. METHODS: The captures were conducted with modified Disney traps, using hamster (Mesocricetus auratus) as bait, from May 2004 to January 2006. RESULTS: Ten species of phlebotomine sandflies were capt...

  14. Effects of Manufactured-sand on Dry Shrinkage and Creep of High-strength Concrete

    Institute of Scientific and Technical Information of China (English)

    ZHOU Mingkai; WANG Jiliang; ZHU Lide; HE Tusheng

    2008-01-01

    The influences of natural sand, manufactured-sand (MS) and stone-dust (SD) in the manufactured-sand on workability, compressive strength, elastic modulus, drying shrinkage and creep properties of high-strength concrete (HSC) were tested and compared. The results show that the reasonable content (7%-10.5%) of SD in MS will not deteriorate the workability of MS-HSC. It could even improve the workability. Moreover, the compressive strength increases gradually with the increasing SD content,and the MS-HSC with low SD content (smaller than 7%) has the elastic modulus which approaches that of the natural sand HSC, but the elastic modulus reduces when the SD content is high. The influence of the SD content on drying shrinkage performance of MS-HSC is closely related to the hydration age. The shrinkage rate of MS-HSC in the former 7 d age is higher than that of the natural sand HSC, but the difference of the shrinkage rate in the late age is not marked. Meanwhile the shrinkage rate reduces as the fly ash is added; the specific creep and creep coefficient of MS-HSC with 7% SD are close to those of the natural sand HSC.

  15. Dielectric properties of fly ash

    Indian Academy of Sciences (India)

    S C Raghavendra; R L Raibagkar; A B Kulkarni

    2002-02-01

    This paper reports the dielectric properties of fly ash. The dielectric measurements were performed as a function of frequency and temperature. The sample of fly ash shows almost similar behaviour in the frequency and temperature range studied. The large value of dielectric constant in the typical frequency range is because of orientation polarization and tight binding force between the ions or atoms in the fly ash. The sample of fly ash is of great scientific and technological interest because of its high value of dielectric constant (104).

  16. Sands at Gusev Crater, Mars

    Science.gov (United States)

    Cabrol, Nathalie A.; Herkenhoff, Kenneth E.; Knoll, Andrew H.; Farmer, Jack D.; Arvidson, Raymond E.; Grin, E.A.; Li, Ron; Fenton, Lori; Cohen, B.; Bell, J.F.; Yingst, R. Aileen

    2014-01-01

    Processes, environments, and the energy associated with the transport and deposition of sand at Gusev Crater are characterized at the microscopic scale through the comparison of statistical moments for particle size and shape distributions. Bivariate and factor analyses define distinct textural groups at 51 sites along the traverse completed by the Spirit rover as it crossed the plains and went into the Columbia Hills. Fine-to-medium sand is ubiquitous in ripples and wind drifts. Most distributions show excess fine material, consistent with a predominance of wind erosion over the last 3.8 billion years. Negative skewness at West Valley is explained by the removal of fine sand during active erosion, or alternatively, by excess accumulation of coarse sand from a local source. The coarse to very coarse sand particles of ripple armors in the basaltic plains have a unique combination of size and shape. Their distribution display significant changes in their statistical moments within the ~400 m that separate the Columbia Memorial Station from Bonneville Crater. Results are consistent with aeolian and/or impact deposition, while the elongated and rounded shape of the grains forming the ripples, as well as their direction of origin, could point to Ma'adim Vallis as a possible source. For smaller particles on the traverse, our findings confirm that aeolian processes have dominated over impact and other processes to produce sands with the observed size and shape patterns across a spectrum of geologic (e.g., ripples and plains soils) and aerographic settings (e.g., wind shadows).

  17. Flying over decades

    Science.gov (United States)

    Hoeller, Judith; Issler, Mena; Imamoglu, Atac

    Levy flights haven been extensively used in the past three decades to describe non-Brownian motion of particles. In this presentation I give an overview on how Levy flights have been used across several disciplines, ranging from biology to finance to physics. In our publication we describe how a single electron spin 'flies' when captured in quantum dot using the central spin model. At last I motivate the use of Levy flights for the description of anomalous diffusion in modern experiments, concretely to describe the lifetimes of quasi-particles in Josephson junctions. Finished PhD at ETH in Spring 2015.

  18. Vision in flying insects.

    Science.gov (United States)

    Egelhaaf, Martin; Kern, Roland

    2002-12-01

    Vision guides flight behaviour in numerous insects. Despite their small brain, insects easily outperform current man-made autonomous vehicles in many respects. Examples are the virtuosic chasing manoeuvres male flies perform as part of their mating behaviour and the ability of bees to assess, on the basis of visual motion cues, the distance travelled in a novel environment. Analyses at both the behavioural and neuronal levels are beginning to unveil reasons for such extraordinary capabilities of insects. One recipe for their success is the adaptation of visual information processing to the specific requirements of the behavioural tasks and to the specific spatiotemporal properties of the natural input.

  19. Recycling of municipal solid waste incinerator fly ash by using hydrocyclone separation.

    Science.gov (United States)

    Ko, Ming-Sheng; Chen, Ying-Liang; Wei, Pei-Shou

    2013-03-01

    The municipal solid waste incinerators (MSWIs) in Taiwan generate about 300,000 tons of fly ash annually, which is mainly composed of calcium and silicon compounds, and has the potential for recycling. However, some heavy metals are present in the MSWI fly ash, and before recycling, they need to be removed or reduced to make the fly ash non-hazardous. Accordingly, the purpose of this study was to use a hydrocyclone for the separation of the components of the MSWI fly ash in order to obtain the recyclable portion. The results show that chloride salts can be removed from the fly ash during the hydrocyclone separation process. The presence of a dense medium (quartz sand in this study) is not only helpful for the removal of the salts, but also for the separation of the fly ash particles. After the dense-medium hydrocyclone separation process, heavy metals including Pb and Zn were concentrated in the fine particles so that the rest of the fly ash contained less heavy metal and became both non-hazardous and recyclable.

  20. Fly ash quality and utilization

    Energy Technology Data Exchange (ETDEWEB)

    Barta, L.E.; Lachner, L.; Wenzel, G.B. [Inst. for Energy, Budapest (Hungary); Beer, M.J. [Massachusetts Inst. of Technology, Cambridge, MA (United States)

    1995-12-01

    The quality of fly ash is of considerable importance to fly ash utilizers. The fly ash puzzolanic activity is one of the most important properties that determines the role of fly ash as a binding agent in the cementing process. The puzzolanic activity, however is a function of fly ash particle size and chemical composition. These parameters are closely related to the process of fly ash formation in pulverized coal fired furnaces. In turn, it is essential to understand the transformation of mineral matter during coal combustion. Due to the particle-to-particle variation of coal properties and the random coalescence of mineral particles, the properties of fly ash particles e.g. size, SiO{sub 2} content, viscosity can change considerably from particle to particle. These variations can be described by the use of the probability theory. Since the mean values of these randomly changing parameters are not sufficient to describe the behavior of individual fly ash particles during the formation of concrete, therefore it is necessary to investigate the distribution of these variables. Examples of these variations were examined by the Computer Controlled Scanning Electron Microscopy (CCSEM) for particle size and chemical composition for Texas lignite and Eagel Butte mineral matter and fly ash. The effect of combustion on the variations of these properties for both the fly ash and mineral matter were studied by using a laminar flow reactor. It is shown in our paper, that there are significant variations (about 40-50% around the mean values) of the above-listed properties for both coal samples. By comparing the particle size and chemical composition distributions of the mineral matter and fly ash, it was possible to conclude that for the Texas lignite mineral matter, the combustion did not effect significantly the distribution of these properties, however, for the Eagel Butte coal the combustion had a major impact on these mineral matter parameters.

  1. A new species, new immature stages, and new synonymy in Australian Dasybasis flies (Diptera: Tabanidae: Diachlorini).

    Science.gov (United States)

    Ferguson, David J; Yeates, David K

    2015-04-09

    Australian beach sand is a productive habitat for lower brachyceran fly larvae but often overlooked by collectors. We collected two species of tabanid larvae from coastal beach sand in southern New South Wales in August 2013. Both species belong to the Dasybasis macrophthalma species-group of Mackerras (1959), one a new species, and the other D. exulans (Erichson, 1842). We describe both new immature stages and the new species adult as Dasybasis rieki sp. nov. (Diptera: Tabanidae: Diachlorini). Trojan (1994b) elevated the D. macrophthalma species group to the genus Sznablius. We review the evidence for the generic status of Sznablius, and synonymize it with Dasybasis.

  2. Physics of flying

    Science.gov (United States)

    Vetrone, Jim

    2015-05-01

    Column editor's note: As the school year comes to a close, it is important to start thinking about next year. One area that you want to consider is field trips. Many institutions require that teachers plan for a field trip well in advance. Keeping that in mind, I asked Jim Vetrone to write an article about the fantastic field trip he takes his AP Physics students on. I had the awesome opportunity to attend a professional development day that Jim arranged at iFLY in the Chicago suburbs. The experience of "flying" in a wind tunnel was fabulous. Equally fun was watching the other physics teachers come up with experiments to have the professional "flyers" perform in the tube. I could envision my students being similarly excited about the experience and about the development of their own experiments. After I returned to school, I immediately began the process of trying to get this field trip approved for the 2015-16 school year. I suggest that you start your process as well if you hope to try a new field trip next year. The key to getting the approval, in my experience, is submitting a proposal early that includes supporting documentation from sources. Often I use NGSS or state standards as justifications for my field trips. I have also quoted College Board expectations for AP Physics 1 and 2 in my documents when requesting an unusual field trip.quote>

  3. DPTM simulation of aeolian sand ripple

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Aeolian sand ripple and its time evolution are simulated by the discrete particle tracing method (DPTM) presented in this paper. The difference between this method and the current methods is that the former can consider the three main factors relevant to the formation of natural aeolian sand ripples,which are the wind-blown sand flux above the sand bed formed by lots of sand particles with different di-ameters,the particle-bed collision and after it the rebound and ejection of sand particles in the sand bed,the saltation of high-speed sand particles and the creep of low-speed sand particles,respectively. The simulated aeolian sand ripple is close to the natural sand ripple not only in basic shape and characteristic,particle size segregation and stratigraphy,but also in formation stages. In addition,three important speeds can be obtained by this method,which are the propagation speed of the saturated aeolian sand ripple and the critical frictional wind speeds of emergence and disappearance of sand ripple.

  4. DPTM simulation of aeolian sand ripple

    Institute of Scientific and Technical Information of China (English)

    ZHENG XiaoJing; BO TianLi; XIE Li

    2008-01-01

    Aeolian sand ripple and its time evolution are simulated by the discrete particle tracing method (DPTM) presented in this paper.The difference between this method and the current methods is that the former can consider the three main factors relevant to the formation of natural aeolian sand ripples, which are the wind-blown sand flux above the sand bed formed by lots of sand particles with different di-ameters, the particle-bed collision and after it the rebound and ejection of sand particles in the sand bed, the saltation of high-speed sand particles and the creep of low-speed sand particles, respectively.The simulated aeolian sand ripple is close to the natural sand ripple not only in basic shape and characteristic, particle size segregation and stratigraphy, but also in formation stages.In addition, three important speeds can be obtained by this method, which are the propagation speed of the saturated aeolian sand ripple and the critical frictional wind speeds of emergence and disappearance of sand ripple.

  5. Dry reusing and wet reclaiming of used sodium silicate sand

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Based on the characteristics of used sodium silicate sand and the different use requirements for recycled sand, "dry reusing and wet reclaiming of used sodium silicate sand" is considered as the most suitable technique for the used sand. When the recycled sand is used as support sand, the used sand is only reused by dry process including breaking, screening, dust-removal, etc., and it is not necessary that the used sand is reclaimed with strongly rubbing and scraping method, but when the recycled sand is used as facing sand (or single sand), the used sand must be reclaimed by wet method for higher removal rate of the residual binders. The characteristics and the properties of the dry reused sand are compared with the wet reclaimed sand after combining the different use requirements of support sand and facing sand (or single sand), and above the most adaptive scheme has also been validated.

  6. Sand and Water Table Play

    Science.gov (United States)

    Wallace, Ann H.; White, Mary J.; Stone, Ryan

    2010-01-01

    The authors observed preschoolers engaged at the sand and water table to determine if math could be found within their play. Wanting to understand how children interact with provided materials and what kinds of math ideas they explore during these interactions, the authors offer practical examples of how such play can promote mathematical…

  7. UK silica sand resources for fracking

    OpenAIRE

    Mitchell, Clive

    2013-01-01

    UK silica sand resources for fracking Clive Mitchell, Industrial Minerals Specialist, British Geological Survey, Keyworth, Nottingham, NG12 5GG Email: Silica sand is high purity quartz sand that is mainly used for glass production, as foundry sand, in horticulture, leisure and other industrial uses. One specialist use is as a ‘proppant’ to enhance oil and gas recovery. This presentation will focus on this application, particularly for shale gas recovery where it is mo...

  8. Moonlight and blood-feeding behaviour of Lutzomyia intermedia and Lutzomyia whitmani (Diptera:Psychodidae:Phlebotominae, vectors of American cutaneous leishmaniasis in Brazil

    Directory of Open Access Journals (Sweden)

    Nataly A Souza

    2005-02-01

    Full Text Available Lutzomyia intermedia (Lutz & Neiva, 1912 and L. whitmani (Antunes & Coutinho, 1939 (Diptera: Psychodidae: Phlebotominae, two important vectors of American cutaneous leishmaniasis in Brazil, occur in sympatry in the locality of Posse county, Petrópolis municipality, state of Rio de Janeiro, Brazil. We investigated the influence of the lunar cycle on the frequency of specimens of the two species caught while attempting to bite the collectors and in CDC light traps. Analysis of the numbers of sand flies captured in different lunar phases for two consecutive years in the peridomestic site and forest shows that there is a significant positive correlation between moonlight intensity and the numbers of L. intermedia and L. whitmani females collected while blood-feeding, whereas the opposite was observed for the CDC traps.

  9. Autogenous shrinkage prediction on high-performance concrete of fly ash based on BP neural network

    Science.gov (United States)

    Wang, Baomin; Zhang, Wenping; Wang, Lijiu

    2006-11-01

    The article adopts test data of neural network for autogenous shrinkage to train and predict on the data which doesn't join training. The article's prediction is on the basis of common medium sand, 5-31.5mm limestone rubble, second class fly-ash, P.O42.5 silicate cement, considering factors include five ones such as ratio of water and cement, sand rate, content of cement, content of fly ash, etc.By adjusting various parameters of neural network structure, it obtains three optimized results of neural network simulation. The error between concrete autogtenous shrinkage value of neural network prediction and trial value is within 3%, which can meet requirement of the concrete engineering.

  10. Treating tar sands formations with karsted zones

    Energy Technology Data Exchange (ETDEWEB)

    Vinegar, Harold J. (Bellaire, TX); Karanikas, John Michael (Houston, TX)

    2010-03-09

    Methods for treating a tar sands formation are described herein. The tar sands formation may have one or more karsted zones. Methods may include providing heat from one or more heaters to one or more karsted zones of the tar sands formation to mobilize fluids in the formation. At least some of the mobilized fluids may be produced from the formation.

  11. Current Methods to Detoxify Fly Ash from Waste Incineration

    Energy Technology Data Exchange (ETDEWEB)

    Hallgren, Christine; Stroemberg, Birgitta [TPS Termiska Processer AB, Nykoeping (Sweden)

    2004-07-01

    Fly ash from waste incineration contains large amounts of heavy metals and dioxins, which will cause a significant disposal problem within the coming years. The amount of fly ash produced in Sweden is currently approximately 60,000 tons/y. New technological options for the decontamination and/or inertization of incinerator fly ash are being developed with the objective of rendering a product that can be reused or, at least, be deposited at standard landfill sites with no risk. Many of these technologies have been tested at industrial scale or in pilot projects. The proposed alternatives include: Thermal treatments; Immobilization/stabilization by cement based techniques; Wet chemical treatments (extractions, immobilizations); Microbiological treatments. Of these, thermal treatments are the most promising solution. Depending on the temperature thermal treatments are classified in two main types: 1) low temperature (below 600 deg C) thermal treatments and 2) high temperature (above 1200 deg C) thermal treatments (vitrification). Most dioxins can be successfully destroyed at temperatures up to 400 deg C under oxygen deficient conditions and at temperatures up to 600 deg C under oxidising conditions. However most heavy metals remain in the fly ash after low temperature treatment. At a temperature of 900 deg C most heavy metals can also be removed in a 10% HCl atmosphere by forming volatile metal chlorides (CT-Fluapur process). During vitrification processes the fly ash melts and forms an inert glassy slag. The product does not leach any significant amount of heavy metals and is free from dioxin. The volume of the fly ash is significantly reduced. The product can be land filled at low costs or used as construction material. The properties of the product depend on the cooling process and on additives such as sand, limestone or waste glass. A series of vitrification methods at industrial size or in pilot scale using different furnaces are studied. Among these, plasma

  12. Sand Waves. Report 1. Sand Wave Shoaling in Navigation Channels

    Science.gov (United States)

    1992-09-01

    heights range from 0.8 m in the Minas Basin, Bay of Fundy (Dalrymple 1984) to 6.0 m in the Bahia Blanca Estuary, Argentina (Aliotta and Perillo 1987...26 PART IV: SITE-SPECIFIC SAND WAVE SHOALING PROBLEMS .. ........ 30 Columbia River Navigation Channel ........ ............... .. 30 Panama ...problem location discussed in this report is at St. Andrew Bay near Panama City, Florida. A relatively short section of the jettied inlet channel requires

  13. Impact of Phlebotomine Sand Flies on U.S. Military Operations at Tallil Air Base, Iraq: 2. Temporal and Geographic Distribution of Sand Flies

    Science.gov (United States)

    2007-01-01

    be important vectors of Leish- mania in Iraq. P. sergenti and P. papatasi are almost certainly the primary vectors of Leishmania tropica (Wright...acterization of two of the Leishmania isolates indi- cated that they were unlike L. infantum, L. donovani, L. tropica , L. majo, or L. aethiopica. In 1985, Sukkar...Lane. 1988. Phlebotomus sergenti, a vec- tor of Leishmania tropica in Saudi Arabia. Trans. R. Soc. Trop. Med. Hyg. 82: 416. Azizi, K., Y. Rassi, E

  14. American Religion

    Institute of Scientific and Technical Information of China (English)

    田甜

    2008-01-01

    It is said that American religion,as a great part of American culture,plays an important role in American culture. It is hoped that some ideas can be obtained from this research paper,which focuses on analyzing the great impact is produced to American culture by American religion. Finally, this essay gives two useful standpoints to English learners:Understunding American religion will help understand the American history, culture and American people,and help you to communic.ate with them better. Understanding American religion will help you understand English better.

  15. Roll Control in Fruit Flies

    CERN Document Server

    Beatus, Tsevi; Cohen, Itai

    2014-01-01

    Due to aerodynamic instabilities, stabilizing flapping flight requires ever-present fast corrective actions. Here we investigate how flies control body roll angle, their most susceptible degree of freedom. We glue a magnet to each fly, apply a short magnetic pulse that rolls it in mid-air, and film the corrective maneuver. Flies correct perturbations of up to $100^{\\circ}$ within $30\\pm7\\mathrm{ms}$ by applying a stroke-amplitude asymmetry that is well described by a linear PI controller. The response latency is $\\sim5\\mathrm{ms}$, making the roll correction reflex one of the fastest in the animal kingdom.

  16. METHOD OF PROCESSING MONAZITE SAND

    Science.gov (United States)

    Welt, M.A.; Smutz, M.

    1958-08-26

    A process is described for recovering thorium, uranium, and rare earth values from monazite sand. The monazite sand is first digested with sulfuric acid and the resulting "monazite sulfate" solution is adjusted to a pH of between 0.4 and 3.0, and oxalate anions are added causing precipitation of the thorium and the rare earths as the oxalates. The oxalate precipitate is separated from the uranium containing supernatant solution, and is dried and calcined to the oxides. The thorium and rare earth oxides are then dissolved in nitric acid and the solution is contacted with tribntyl phosphate whereby an organic extract phase containing the cerium and thorium values is obtained, together with an aqueous raffinate containing the other rare earth values. The organic phase is then separated from the aqueous raffinate and the cerium and thorium are back extracted with an aqueous medium.

  17. Thermal Properties of oil sand

    Science.gov (United States)

    LEE, Y.; Lee, H.; Kwon, Y.; Kim, J.

    2013-12-01

    Thermal recovery methods such as Cyclic Steam Injection or Steam Assisted Gravity Drainage (SAGD) are the effective methods for producing heavy oil or bitumen. In any thermal recovery methods, thermal properties (e.g., thermal conductivity, thermal diffusivity, and volumetric heat capacity) are closely related to the formation and expansion of steam chamber within a reservoir, which is key factors to control efficiency of thermal recovery. However, thermal properties of heavy oil or bitumen have not been well-studied despite their importance in thermal recovery methods. We measured thermal conductivity, thermal diffusivity, and volumetric heat capacity of 43 oil sand samples from Athabasca, Canada, using a transient thermal property measurement instrument. Thermal conductivity of 43 oil sand samples varies from 0.74 W/mK to 1.57 W/mK with the mean thermal conductivity of 1.09 W/mK. The mean thermal diffusivity is 5.7×10-7 m2/s with the minimum value of 4.2×10-7 m2/s and the maximum value of 8.0×10-7 m2/s. Volumetric heat capacity varies from 1.5×106 J/m3K to 2.11×106 J/m3K with the mean volumetric heat capacity of 1.91×106 J/m3K. In addition, physical and chemical properties (e.g., bitumen content, electric resistivity, porosity, gamma ray and so on) of oil sand samples have been measured by geophysical logging and in the laboratory. We are now proceeding to investigate the relationship between thermal properties and physical/chemical properties of oil sand.

  18. Formation of Craters in Sand

    Directory of Open Access Journals (Sweden)

    Vanissra Boonyaleepun

    2007-06-01

    Full Text Available The diameter of craters formed by spheres of varying mass dropped into sand at low speed was studied. The relationship between the diameter of the crater formed and the kinetic energy of the projectile at impact was found to be of the same general form as that for planetary meteor craters. The relationship is shown to be a power law with exponent 0.17.

  19. Silo model tests with sand

    DEFF Research Database (Denmark)

    Munch-Andersen, Jørgen

    Tests have been carried out in a large silo model with Leighton Buzzard Sand. Normal pressures and shear stresses have been measured during tests carried out with inlet and outlet geometry. The filling method is a very important parameter for the strength of the mass and thereby the pressures...... as well as the flow pattern during discharge of the silo. During discharge a mixed flow pattern has been identified...

  20. Courtship dances in the flies of the genus Lispe (Diptera: Muscidae): from the fly's viewpoint.

    Science.gov (United States)

    Frantsevich, Leonid; Gorb, Stanislav

    2006-05-01

    Two predatory fly species, Lispe consanguinea Loew, 1858 and L. tentaculata DeGeer, 1776, inhabit the supralittoral zone at the shore of a fresh-water reservoir. Both species look alike and possess similar "badges," reflective concave silvery scales on the face. Flies occupy different lek habitats. Males of the first species patrol the bare wet sand on the beach just above the surf. Males of the second species reside on the more textured heaps of algae and stones. Courtship and aggressive behaviour of males was video-recorded and analysed frame by frame. Visual stimuli provided by the conspecific partner were computed in the body-fixed space of a fly observer. Males of L. consanguinea perform long pedestrian dances of pendulating circular arcs (frequency 2 s(-1), median radius 2.5 cm, linear velocity 0.130 m/s). Right and left side runs are equally probable. Circular runs are interrupted by standby intervals of average duration 0.35 s. The female views the male as a target covering 2 by 2 ommatidia, moving abruptly with the angular velocity over 200 degrees/s in a horizontal direction down the path of about 50 degrees till the next standpoint. Dancing is evenly distributed around the female. On the contrary, the male fixates the image of the female within the narrow front sector (median +/-10 degrees); the target in his view has 6-7 times less angular velocity and angular span of oscillations, and its image in profile overlays 6-8 by 2 ommatidia. If the female walks, the male combines tracking with voluntary circular dances. Rival males circle about one another at a distance shorter than 15 mm, but not in close contact. Males of L. tentaculata are capable of similar circular courting dances, but do so rarely. Usually they try to mount any partner immediately. In the latter species, male combat consists of fierce wrestling. Flies of both species often walk sideward and observe the partner not in front but at the side.

  1. Spread Across Liquids Continues to Fly

    Science.gov (United States)

    Miller, Fletcher J.

    2001-01-01

    The physics and behavior of a flame spreading across a flammable liquid is an active area of research at the NASA Glenn Research Center. Spills of fuels and other liquids often result in considerable fire hazards, and much remains unknown about the details of how a flame, once ignited, moves across a pool. The depth of the liquid or size of the spill, the temperature, and wind, if any, can all complicate the combustion processes. In addition, with the advent of the International Space Station there may be fire hazards associated with cleaning, laboratory, or other fluids in space, and it is essential to understand the role that gravity plays in such situations. The Spread Across Liquids (SAL) experiment is an experimental and computational effort dedicated to understanding the detailed mechanisms of flame spread across a flammable liquid initially below its flashpoint temperature. The experimental research is being carried out in-house by a team of researchers from Glenn, the National Center for Microgravity Combustion, and Zin Technologies, with computer modeling being provided via a grant with the University of California, Irvine. Glenn's Zero Gravity Facility is used to achieve short microgravity periods, and normal gravity testing is done in the Space Experiments Laboratory. To achieve longer periods of microgravity, the showcase SAL hardware flies aboard a sounding rocket launched from White Sands Missile Range, New Mexico, approximately once per year. In addition to extended microgravity, this carrier allows the use of detailed diagnostics that cannot be employed in a drop tower.

  2. An experimental investigation into the trapping model core pillars with reinforced fly ash composites

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, M.K. [National Inst. of Technology, Rourkela (India); Karanam, U.M. [Indian Inst. of Technology, Kharagpur (India)

    2008-06-15

    This paper presented details of a study which examined the use of fly ash composite materials for backfilling mine voids in room-and-pillar mining techniques. The study examined the load deformation characteristics of model core pillars confined by wire mesh reinforced fly ash composite materials. Anhydrous chemical-grade lime and gypsum were added in various quantities to class F fly ash samples. The model core pillars were 57 mm in diameter and 200 mm in length. The engineering properties of the model core pillars were then determined using unconfined compressive strength and Brazilian indirect tensile strength tests. The experimental investigations showed that the percentage increases in the strength of the trapped model core pillars varied with the different types of composite materials, and was also influenced by the length of the curing period and the ratio of the annular thickness of the fill area to the model core pillar radius. Results demonstrated that the addition of excess lime to fly ash composites was not beneficial. Maximum strength gains of 14 per cent were achieved with model cores of a cement-sand ratio of 1:2.5 for fly ash composites containing 15 per cent lime and 5 per cent gypsum. It was concluded that suitable fly ash composites reinforced with wire ropes can enhance the strength of the load bearing element and alter the post-peak characteristics of trapped cores.

  3. Subtropical Fruit Fly Invasions into Temperate Fruit Fly Territory in California's San Joaquin Valley

    Science.gov (United States)

    Subtropical fruit fly species including peach fruit fly, Bactrocera zonata (Saunders); melon fly, B. cucurbitae (Coquillett); oriental fruit fly, B. dorsalis (Hendel); and Mediterranean fruit fly, Ceratitis capitata Weidemann, have been detected in the past decade in the San Joaquin Valley of Califo...

  4. Managing the Fruit Fly Experiment.

    Science.gov (United States)

    Jeszenszky, Arleen W.

    1997-01-01

    Describes a sophisticated version of the fruit fly experiment for teaching concepts about genetics to biology students. Provides students with the opportunity to work with live animals over an extended period. (JRH)

  5. Quantitative proteomics on the fly

    NARCIS (Netherlands)

    Gouw, J.W.

    2009-01-01

    The development of multicellular organisms is characterized by complex processes that progressively transform essentially a single cell into a creature with complicated structures and highly specialized functions. The fruit fly Drosophila melanogaster provides an excellent model system to investigat

  6. Fly ash. Quality recycling material

    Energy Technology Data Exchange (ETDEWEB)

    Blomster, D.; Leisio, C.

    1996-11-01

    Imatran Voima`s coal-fired power plants not only generate power and heat but also produce fly ash which is suitable raw material for recycling. This material for recycling is produced in the flue gas cleaning process. It is economical and, thanks to close quality control, is suitable for use as a raw material in the building materials industry, in asphalt production, and in earthworks. Structures made from fly ash are also safe from an environmental point of view. (orig.)

  7. Substitution of the clayey mineral component by lignite fly ash in portland cement clinker synthesis

    Directory of Open Access Journals (Sweden)

    Jovanović Nataša

    2006-01-01

    Full Text Available Fly ash from four power plants in Serbia (PP "Morava" - Svilajnac, PP "Kolubara" - Veliki Grijani, PP "Kostolac" - units B1 and B2 - Kostolac and PP "Nikola Tesla" - units A and B - Obrenovac was utilized as the starting raw component for Portland cement clinker synthesis. Limestone and quartz sand from the "Holcim - Serbia, a.d." cement factory were the other two starting raw components. Based on the chemical composition of the raw components and from the projected cement moduli, the amounts of raw components in the raw mixtures were calculated. Six different raw mixtures were prepared - each one consisted of limestone, sand and different fly ash. A raw mixture from the industrial production of the "Holcim - Serbia, a.d." cement factory was used as the reference material. The prepared raw mixtures were sintered in a laboratory furnace at 1400°C. The chemical and mineralogical compositions of the synthesized clinkers were determined. The characteristics of clinkers, based on fly ash, were compared to the characteristics of the industrial Portland cement clinker from the "Holcim - Serbia, a.d." cement factory. The results of the investigation showed that fly ash from power plants in Serbia can be suitable for Portland cement clinker synthesis.

  8. Flying in Two Dimensions

    CERN Document Server

    Prakash, Manu

    2011-01-01

    Diversity and specialization of behavior in insects is unmatched. Insects hop, walk, run, jump, row, swim, glide and fly to propel themselves in a variety of environments. We have uncovered an unusual mode of propulsion of aerodynamic flight in two dimensions in Waterlilly Beetles \\emph{(Galerucella)}. The adult beetles, often found in water lilly ponds, propel themselves strictly in a two-dimensional plane on the surface of water via flapping wing flight. Here we analyze the aerodynamics of this peculiar flight mode with respect to forces exerted on the organism during flight. The complexity of 2-D flight is captured by accounting for additional forces beyond gravitational, thrust, lift and drag, exerted on the insect body in 3D flight. Understanding this constrained propulsion mode requires accounting for viscous drag, surface tension, buoyancy force, and capillary-wave drag. Moreover, dramatic differences exist in the magnitude of the resultant forces in 2D vs. 3D flight. Here, in this fluid dynamics video...

  9. Sand deposit-detecting method and its application in model test of sand flow

    Institute of Scientific and Technical Information of China (English)

    黎伟; 房营光; 莫海鸿; 谷任国; 陈俊生

    2013-01-01

    Against the background of the sand-flow foundation treatment engineering of Guangzhou Zhoutouzui variable cross-section immersed tunnel, a kind of sand deposit-detecting method was devised on the basis of full-scale model test of sand-flow method. The real-time data of sand-deposit height and radius were obtained by the self-developed sand-deposit detectors. The test results show that the detecting method is simple and has high precision. In the use of sand-flow method, the sand-carrying capability of fluid is limited, and sand particles are all transported to the sand-deposit periphery through crater, gap and chutes after the sand deposit formed. The diffusion range of the particles outside the sand-deposit does not exceed 2.0 m. Severe sorting of sand particles is not observed because of the unique oblique-layered depositing process. The temporal and spatial distributions of gap and chutes directly affect the sand-deposit expansion, and the expansion trend of the average sand-deposit radius accords with quadratic time-history curve.

  10. Sand fly captures with Disney traps in area of occurrence of Leishmania (Leishmania amazonensis in the state of Mato Grosso do Sul, mid-western Brazil Capturas de flebotomíneos com armadilhas de Disney em área de ocorrência de Leishmania (Leishmania amazonensis no estado de Mato Grosso do Sul, região Centro-Oeste do Brasil

    Directory of Open Access Journals (Sweden)

    Maria Elizabeth Cavalheiros Dorval

    2010-10-01

    Full Text Available INTRODUCTION: The work was conducted to study phlebotomine fauna (Diptera: Psychodidae and aspects of American cutaneous leishmaniasis transmission in a forested area where Leishmania (Leishmania amazonensis occurs, situated in the municipality of Bela Vista, State of Mato Grosso do Sul, Brazil. METHODS: The captures were conducted with modified Disney traps, using hamster (Mesocricetus auratus as bait, from May 2004 to January 2006. RESULTS: Ten species of phlebotomine sandflies were captured: Brumptomyia avellari, Brumptomyia brumpti, Bichromomyia flaviscutellata, Evandromyia bourrouli, Evandromyia lenti, Lutzomyia longipalpis, Psathyromyia campograndensis, Psathyromyia punctigeniculata, Psathyromyia shannoni and Sciopemyia sordellii. The two predominant species were Ev bourrouli (57.3% and Bi flaviscutellata (41.4%, present at all sampling sites. Two of the 36 hamsters used as bait presented natural infection with Leishmania. The parasite was identified as Leishmania (Leishmania amazonensis. CONCLUSIONS: Analysis of the results revealed the efficiency of Disney traps for capturing Bichromomyia flaviscutellata and the simultaneous presence of both vector and the Leishmania species transmitted by the same can be considered a predictive factor of the occurrence of leishmaniasis outbreaks for the human population that occupies the location.INTRODUÇÃO: O estudo foi realizado com o objetivo de estudar a fauna de flebotomíneos (Diptera: Psychodidae e aspectos ligados à transmissão da leishmaniose tegumentar americana em uma área florestal com ocorrência de Leishmania (Leishmania amazonensis, situada no município de Bela Vista, Estado do Mato Grosso do Sul, Brasil. MÉTODOS: As capturas de flebotomíneos foram realizadas utilizando-se armadilhas tipo Disney modificadas, com isca roedor, Mesocricetus auratus, no período de maio de 2004 a janeiro de 2006. RESULTADOS: As coletas resultaram na identificação de 10 espécies de Phlebotominae

  11. MANUAL. Fly ash in civil engineering, Gravel roads; HANDBOK. Flygaska i mark- och vaegbyggnad, Grusvaegar

    Energy Technology Data Exchange (ETDEWEB)

    Munde, Hanna; Svedberg, Bo; Macsik, Josef; Maijala, Aino; Lahtinen, Pentti; Ekdahl, Peter; Neren, Jens [Vattenfall AB, Stockholm (Sweden). Vaerme Norden

    2006-01-15

    Fly ash based on biofuels or coal has been used as construction material for a long time in roads and other civil engineering applications. Some example, where it has been used in roadbase and subbase of gravel roads, are in the counties of Uppsala, Soedermanland, Vaestmanland and in Finland. The use of fly ash has contributed to good function for example as bearing capacity, thaw and frost capacity and good durability. This has also reduced costs for maintenance. The objective of this project was to develop a manual to provide a base for contemporary use of fly ash in road constructions. In the manual experience from studies, field tests and regulations has been compiled. The manual handles fly ash as base for products to be used in base and subbase in gravel roads. Future user of the guidelines are mainly consultant engineers and contractors. However the aim of the manual is to also support road administrators, environmental authorities and industry. The project has been carried out parallel to another ongoing national project titled 'Guidelines, Use of alternative materials in civil engineering'. The objective of that project is to establish a base for handling of alternative materials in Sweden. Fly ash in gravel roads are mainly used in two typical applications, one without any additive in a single layer and one with fly ash mixed with gravel. The use of flyash provides functional properties such as increased stiffness, stability and enhanced frost and thaw capacity for the road construction in total. Furthermore the products based on fly ash will have low permeability and good frost and thaw durability. These properties are for example related to fly ash quality, design and construction and are in general expected to be better than for traditional constructions using, for example, sand or gravel. The properties can be enhanced further by using binders such as cement and Merit. Fly ash should always be used above the ground water table with

  12. Creep Behavior of Frozen Sand.

    Science.gov (United States)

    1981-06-01

    temperature and stress range. There was a 2strong stress dependance to S (r =0.95) for saturated Manchester Fine Sand which does not agree with RPT. The...Curves at High Stress 161 Ratio D/Du = 0.505 for Frozen HF’S at w=10% IV-20 Minimum Strain Rate Dependance on Stress 162 Ratio for Frozen MFS IV-21 Minimum...Strain Rate Dependance on Relative 163 Density for Frozen MFS IV-22 Temperature Stage Test on Frozen Saturated 164 MFS under a Load of D=9.24MPa Fig

  13. Liquefaction of Sand under Low Confining Pressure

    Institute of Scientific and Technical Information of China (English)

    YANG Shaoli; Rolf Sandven; Lars Grande

    2003-01-01

    Undrained behaviour of sand under low cell pressure was studied in static and cyclic triaxial tests. It was found that very loose sand liquefies under static loading with the relative density being a key parameter for the undrained behaviour of sand. In cyclic triaxial tests, pore water pressures built up during the cyclic loading and exceeded the confining cell pressure. This process was accompanied by a large sudden increase in axial deformation. The necessary number of cycles to obtain liquefaction was related to the confining cell pressure, the amplitude of cyclic loading and the relative density of sand.In addition, the patterns of pore water pressure response are different from those of sand samples with different relative densities. The test results are very useful for expounding scour mechanism around coastal structures since they relate to the low stress behaviour of the sand.

  14. Recent advances in waterglass sand technologies

    Institute of Scientific and Technical Information of China (English)

    ZHU Chun-xi

    2007-01-01

    This paper reports some new understandings and advances in waterglass sand technologies. The multiple chemical modification process can increase the binding strength of the waterglass sand by up to 50%-70%.Therefore, the additions of the modified waterglass can be decreased to 3.0%-4.0% for CO2 process and to 2.0%-2.5% for organic ester hardening process, and greatly improve the collapsibility and reclaimability of the sand. Based on the new understandings and experimental results reported in this paper, several original ideas, such as nano modification, have been proposed to promote advances of waterglass sand technologies,

  15. PROSPECTS FIXATION DRIFT SANDS PHYSICOCHEMICAL METHOD

    Directory of Open Access Journals (Sweden)

    Maujuda MUZAFFAROVA

    2016-09-01

    Full Text Available This article is based on the theoretical foundations of secure mobile sand being considered for reducing the negative impact of one of the manifestations of exogenous plains on such an important natural-technical system as a railroad. It suggests practical measures to build a system of design protection against sand drifts. The article also suggests ways to conserve resources and rational use of machinery and performers as well as the consolidation of mobile sand wet with water soluble waste of local production of waste dextrin. Consolidation is exposed on dry and wet sand.

  16. Fly-in/Fly-out: Implications for Community Sustainability

    Directory of Open Access Journals (Sweden)

    Keith Storey

    2010-04-01

    Full Text Available “Fly-in/fly-out” is a form of work organization that has become the standard model for new mining, petroleum and other types of resource development in remote areas. In many places this “no town” model has replaced that of the “new town.” The work system has both beneficial and adverse implications for the sustainability of both existing communities near new resource developments and for the more distant communities from which workers are drawn. This paper explores these outcomes drawing upon examples from North America and Australia.

  17. Escherichia coli fliAZY operon.

    OpenAIRE

    Mytelka, D S; Chamberlin, M J

    1996-01-01

    We have cloned the Escherichia coli fliAZY operon, which contains the fliA gene (the alternative sigma factor sigma F) and two novel genes, fliZ and fliY. Transcriptional mapping of this operon shows two start sites, one of which is preceded by a canonical E sigma F-dependent consensus and is dependent on sigma F for expression in vivo and in vitro. We have overexpressed and purified sigma F and demonstrated that it can direct core polymerase to E sigma F-dependent promoters. FliZ and FliY ar...

  18. Evaluation of genotoxicity of coal fly ash in Allium cepa root cells by combining comet assay with the Allium test.

    Science.gov (United States)

    Chakraborty, Rajarshi; Mukherjee, Ashit Kumar; Mukherjee, Anita

    2009-06-01

    Fly ash is a by-product of coal-fired electricity generation plants. Its utilization and disposal is of utmost importance. Using onion (Allium cepa) root tip system, the present study was carried out to evaluate the potential toxic and genotoxic effects of fly ash, collected from a thermal power plant in West Bengal, India. Prior to testing, the collected fly ash sample was mixed with sand in different proportions. Allium bulbs were allowed to germinate directly in fly ash and after five days the germinating roots were processed for the Allium test. Additionally, the Allium test was adapted for detecting DNA damage through comet assay. The results from the Allium test indicate that fly ash at 100% concentration inhibits root growth and mitotic indices; induces binucleated cells as a function of the proportion, but is not toxic at very low concentration. In the comet assay, a statistical increase for DNA strand breaks was found only at higher concentrations. The sample was analyzed by flame atomic absorption spectrometer for Zn, Pb, Cu, Ni, Cd and As, whose presence could partly be responsible for the toxicity of fly ash. The study concludes that the classical Allium test can give a more comprehensive data when done in combination with the comet assay, which is faster, simpler and independent of mitosis. Also when fly ash is used for other purposes in combination with soils, it should be judiciously used at very low concentrations in order to protect the ecosystem health from any potential adverse effects.

  19. Sand Failure Mechanism and Sanding Parameters in Niger Delta Oil Reservoirs

    OpenAIRE

    Sunday Isehunwa,; Andrew Farotade

    2010-01-01

    Sand production is a major issue during oil and gas production from unconsolidated reservoirs. In predicting the onset of sand production, it is important to accurately determine the failure mechanism and the contributing parameters. The aim of this study was to determine sand failure mechanism in the Niger-Delta, identify themajor contributing parameters and evaluate their effects on sanding.Completion and production data from 78 strings completed on 22 reservoirs in a Niger Delta oil Field ...

  20. Fiber optics that fly

    Science.gov (United States)

    Wilcox, Michael J.; Thelen, Donald C., Jr.

    1996-11-01

    The need for autonomous systems to work under unanticipated conditions requires the use of smart sensors. High resolution systems develop tremendous computational loads. Inspiration from animal vision systems can guide us in developing preprocessing approaches implementable in real time with high resolution and deduced computational load. Given a high quality optical path and a 2D array of photodetectors, the resolution of a digital image is determined by the density of photodetectors sampling the image. In order to reconstruct an image, resolution is limited by the distance between adjacent detectors. However, animal eyes resolve images 10-100 times better than either the acceptance angle of a single photodetector or the center-to-center distance between neighboring photodetectors. A new model of the fly's visual system emulates this improved performance, offering a different approach to subpixel resolution. That an animal without a cortex is capable of this performance suggests that high level computation is not involved. The model takes advantage of a photoreceptor cell's internal structure for capturing light. This organelle is a waveguide. Neurocircuitry exploits the waveguide's optical nonlinearities, namely in the shoulder region of its gaussian sensitivity-profile, to extract high resolution information from the visual scene. The receptive fields of optically disparate inputs overlap in space. Photoreceptor input is continuous rather than discretely sampled. The output of the integrating module is a signal proportional to the position of the target within the detector array. For tracking a point source, resolution is 10 times better than the detector spacing. For locating absolute position and orientation of an edge, the model performs similarly. Analog processing is used throughout. Each element is an independent processor of local luminance. Information processing is in real time with continuous update. This processing principle will be reproduced in an

  1. The Effect of Variation of Molarity of Alkali Activator and Fine Aggregate Content on the Compressive Strength of the Fly Ash: Palm Oil Fuel Ash Based Geopolymer Mortar

    Directory of Open Access Journals (Sweden)

    Iftekhair Ibnul Bashar

    2014-01-01

    Full Text Available The effect of molarity of alkali activator, manufactured sand (M-sand, and quarry dust (QD on the compressive strength of palm oil fuel ash (POFA and fly ash (FA based geopolymer mortar was investigated and reported. The variable investigated includes the quantities of replacement levels of M-sand, QD, and conventional mining sand (N-sand in two concentrated alkaline solutions; the contents of alkaline solution, water, POFA/FA ratio, and curing condition remained constant. The results show that an average of 76% of the 28-day compressive strength was found at the age of 3 days. The rate of strength development from 3 to 7 days was found between 12 and 16% and it was found much less beyond this period. The addition of 100% M-sand and QD shows insignificant strength reduction compared to mixtures with 100% N-sand. The particle angularity and texture of fine aggregates played a significant role in the strength development due to the filling and packing ability. The rough texture and surface of QD enables stronger bond between the paste and the fine aggregate. The concentration of alkaline solution increased the reaction rate and thus enhanced the development of early age strength. The use of M-sand and QD in the development of geopolymer concrete is recommended as the strength variation between these waste materials and conventional sand is not high.

  2. Pathogens and bionomics of Lutzomyia apache (Diptera: Psychodidae) from Wyoming, USA

    Science.gov (United States)

    Phlebotomine sand flies are vectors of bacteria, parasites, and viruses. Lutzomyia apache, a North American sand fly, was incriminated as a vector of vesicular stomatitis viruses (VSV) due to overlapping ranges of the sand fly and recent outbreaks of VSV. We report on the discovery of two population...

  3. Dermatobia, the neotropical warble fly.

    Science.gov (United States)

    Sancho, E

    1988-09-01

    The neotropical warble fly, Dermatobia hominis (Fig. 1), has plagued neotropical America since preColombian times, and has become an economically important pest causing substantial losses to the meat, milk and leather industries from northern Mexico down to northern Argentina. Its life cycle (Box 1) is astonishingly complex, requiring another insect as a phoretic carrier of its eggs to the skin of its mammal hosts. Here Eugenio Sancho discusses factors that contribute to the current economic and public health importance of this myiasis-causing fly.

  4. Study of Black Sand Particles from Sand Dunes in Badr, Saudi Arabia Using Electron Microscopy

    Directory of Open Access Journals (Sweden)

    Haider Abbas Khwaja

    2015-08-01

    Full Text Available Particulate air pollution is a health concern. This study determines the microscopic make-up of different varieties of sand particles collected at a sand dune site in Badr, Saudi Arabia in 2012. Three categories of sand were studied: black sand, white sand, and volcanic sand. The study used multiple high resolution electron microscopies to study the morphologies, emission source types, size, and elemental composition of the particles, and to evaluate the presence of surface “coatings or contaminants” deposited or transported by the black sand particles. White sand was comprised of natural coarse particles linked to wind-blown releases from crustal surfaces, weathering of igneous/metamorphic rock sources, and volcanic activities. Black sand particles exhibited different morphologies and microstructures (surface roughness compared with the white sand and volcanic sand. Morphological Scanning Electron Microscopy (SEM and Laser Scanning Microscopy (LSM analyses revealed that the black sand contained fine and ultrafine particles (50 to 500 nm ranges and was strongly magnetic, indicating the mineral magnetite or elemental iron. Aqueous extracts of black sands were acidic (pH = 5.0. Fe, C, O, Ti, Si, V, and S dominated the composition of black sand. Results suggest that carbon and other contaminant fine particles were produced by fossil-fuel combustion and industrial emissions in heavily industrialized areas of Haifa and Yanbu, and transported as cloud condensation nuclei to Douf Mountain. The suite of techniques used in this study has yielded an in-depth characterization of sand particles. Such information will be needed in future environmental, toxicological, epidemiological, and source apportionment studies.

  5. Fruit Flies Help Human Sleep Research

    Science.gov (United States)

    Skip Navigation Bar Home Current Issue Past Issues Fruit Flies Help Human Sleep Research Past Issues / Summer 2007 ... courtesy of NIGMS Neuroscientist Chiara Cirelli uses experimental fruit flies to study sleep. Although it may be tough ...

  6. Silica sand resources in the Netherlands

    NARCIS (Netherlands)

    Meulen, M.J. van der; Westerhoff, W.E.; Menkovic, A.; Gruijters, S.H.L.L.; Dubelaar, C.W.; Maljers, D.

    2009-01-01

    Silica sand, (almost) pure quartz sand, is a valuable and scarce mineral resource within the shallow Dutch subsurface. High-grade deposits are exploited in the southeastemmost part of the country, as raw material for the glass, ceramic, chemical and other process industries. Dutch land-use policy re

  7. Understanding Colombian Amazonian white sand forests

    NARCIS (Netherlands)

    Peñuela-Mora, M.C.

    2014-01-01

    Although progress has been made in studies on white sand forests in the Amazon, there is still a considerable gap in our knowledge of the unique species composition of white sand forests and their structure and dynamics, especially in Western Amazon. This thesis aims to fill this gap by addressing t

  8. Pilot Project Sand Groynes Delfland Coast

    NARCIS (Netherlands)

    Hoekstra, R.; Walstra, D.J.R.; Swinkels, C.S.

    2012-01-01

    In October and November 2009 a pilot project has been executed at the Delfland Coast in the Netherlands, constructing three small sandy headlands called Sand Groynes. Sand Groynes are nourished from the shore in seaward direction and anticipated to redistribute in the alongshore due to the impact of

  9. Sand transportation and reverse patterns over leeward face of sand dune

    Science.gov (United States)

    Jiang, Hong; Dun, Hongchao; Tong, Ding; Huang, Ning

    2017-04-01

    Sand saltation has complex interactions with turbulent flow and dune form. Most models of wind-blown sand consider ideal circumstances such as steady wind velocity and a flat surface, and the bulk of data on wind flow and sand transport over an individual dune has focused mostly on the influence of dune shape or inter-dune space on the wind flow, neglecting the effect of morphology on sand saltation, particularly airflow and sand transportation over the leeward slope. Wind flow structures over the leeward slope of sand dunes have a fundamental influence on the organization of sand dunes. In order to understand sand dune dynamics, lee face airflow and sediment transportation should be paid more attention. Previous field observations could not measure turbulent flow structure well because of the limited observation points and the influence of experiment structure on wind field. In addition, the reverse sand particles over leeward face could not be collected by sand trap in field. Numerous field observations could not measure turbulent flow structure because of the limited observation points and the influence of experimental structures on the wind field. In addition, the reverse transport of sand particles over leeward face could not be collected by sand traps in field. Therefore, this paper aims to investigate the turbulent flow structure and sand transport pattern over the leeward slope. A numerical model of sand saltation over slope terrain is constructed, which also considers the coupling effects between air flow and sand particles. The large eddy simulation method is used to model turbulent flow. Sand transport is simulated by tracking the trajectory of each sand particle. The results show that terrain significantly alters the turbulent air flow structure and wind-blown sand movement, especially over the leeward slope. Here, mass flux increases initially and then decreases with height in the reversed flow region in the direction of wind flow, and the mass flux

  10. Immobilization of cesium in alkaline activated fly ash matrix

    Science.gov (United States)

    Fernandez-Jimenez, A.; Macphee, D. E.; Lachowski, E. E.; Palomo, A.

    2005-11-01

    The immobilization potential of alkaline activated fly ash (AAFA) matrices for cesium has been investigated. The presence of Cs in the AAFA pastes, prepared using 8M NaOH solution as activator, showed no significant adverse effects on mechanical strength or microstructure, nor were significant quantities of Cs leached following application of the Toxic Characteristic Leaching Procedure (TCLP) and American Nuclear Society (ANS) 16.1 leaching protocols. Microstructural analysis shows Cs associated with the main reaction product in the AAFA suggesting that cesium is chemically bound rather than physically encapsulated. It is proposed that cesium is incorporated into the alkaline aluminosilicate gel, a precursor for zeolite formation.

  11. Investigation on Leaching Behaviour of Fly Ash and Bottom Ash Replacement in Self-Compacting Concrete

    Science.gov (United States)

    Kadir, Aeslina Abdul; Ikhmal Haqeem Hassan, Mohd; Bakri Abdullah, Mohd Mustafa Al

    2016-06-01

    Fly ash and bottom ash are some of the waste generated by coal-fired power plants, which contains large quantities of toxic and heavy metals. In recent years, many researchers have been interested in studying on the properties of self-compacting concrete incorporated with fly ash and bottom ash but there was very limited research from the combination of fly ash and bottom ash towards the environmental needs. Therefore, this research was focused on investigating the leachability of heavy metals of SCC incorporated with fly ash and bottom ash by using Toxicity Characteristic Leaching Procedure, Synthetic Precipitation Leaching Procedure and Static Leaching Test. The samples obtained from the coal-fired power plant located at Peninsula, Malaysia. In this study, the potential heavy metals leached out from SCC that is produced with fly ash as a replacement for Ordinary Portland Cement and bottom ash as a substitute for sand with the ratios from 10% to 30% respectively were designated and cast. There are eight heavy metals of concern such as As, Cr, Pb, Zn, Cu, Ni, Mn and Fe. The results indicated that most of the heavy metals leached below the permissible limits from the United States Environmental Protection Agency and World Health Organization limit for drinking water. As a conclusion, the minimum leaching of the heavy metals from the incorporation of fly ash and bottom ash in self-compacting concrete was found in 20% of fly ash and 20% of bottom ash replacement. The results also indicate that this incorporation could minimize the potential of environmental problems.

  12. FliO Regulation of FliP in the Formation of the Salmonella enterica Flagellum

    OpenAIRE

    Barker, Clive S.; Meshcheryakova, Irina V.; Kostyukova, Alla S.; Samatey, Fadel A.

    2010-01-01

    The type III secretion system of the Salmonella flagellum consists of 6 integral membrane proteins: FlhA, FlhB, FliO, FliP, FliQ, and FliR. However, in some other type III secretion systems, a homologue of FliO is apparently absent, suggesting it has a specialized role. Deleting the fliO gene from the chromosome of a motile strain of Salmonella resulted in a drastic decrease of motility. Incubation of the ΔfliO mutant strain in motility agar, gave rise to pseudorevertants containing extrageni...

  13. Sand Failure Mechanism and Sanding Parameters in Niger Delta Oil Reservoirs

    Directory of Open Access Journals (Sweden)

    Sunday Isehunwa,

    2010-05-01

    Full Text Available Sand production is a major issue during oil and gas production from unconsolidated reservoirs. In predicting the onset of sand production, it is important to accurately determine the failure mechanism and the contributing parameters. The aim of this study was to determine sand failure mechanism in the Niger-Delta, identify themajor contributing parameters and evaluate their effects on sanding.Completion and production data from 78 strings completed on 22 reservoirs in a Niger Delta oil Field were evaluated. Sand failure mechanisms and contributing parameters were identified and compared with published profiles. The results showed that cohesive stress is the predominant sand failure mechanism. Water cut, bean size and gas oil ratio (GOR impact sand production in the Niger Delta.

  14. Flies and Campylobacter infection of broiler flocks

    DEFF Research Database (Denmark)

    Hald, Birthe; Skovgård, Henrik; Bang, Dang Duong;

    2004-01-01

    A total of 8.2% of flies caught outside a broiler house in Denmark had the potential to transmit Campylobacter jejuni to chickens, and hundreds of flies per day passed through the ventilation system into the broiler house. Our study suggests that flies may be an important source of Campylobacter...

  15. Louse flies on birds of Baja California.

    Science.gov (United States)

    Tella, J L; Rodríguez-Estrella, R; Blanco, G

    2000-01-01

    Louse flies were collected from 401 birds of 32 species captured in autumn of 1996 in Baja California Sur (Mexico). Only one louse fly species (Microlynchia pusilla) was found. It occurred in four of the 164 common ground doves (Columbina passerina) collected. This is a new a host species for this louse fly.

  16. DURABILITY OF HARDENED FLY ASH PASTE

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    The mechanical properties and durability ( mainly frost-resistance and carbonation resistance ) of fly ash-CaO-CaSO4 .2H2O hardened paste are studied. The relationship among durability of harden ed fly ash paste, the quantity and distribution of hydrates and the initial p aste texture of hardened fly ash paste is presented.

  17. The Spider and the Fly

    Science.gov (United States)

    Mellinger, Keith E.; Viglione, Raymond

    2012-01-01

    The Spider and the Fly puzzle, originally attributed to the great puzzler Henry Ernest Dudeney, and now over 100 years old, asks for the shortest path between two points on a particular square prism. We explore a generalization, find that the original solution only holds in certain cases, and suggest how this discovery might be used in the…

  18. Acetylcholinesterases of blood-feeding flies and ticks.

    Science.gov (United States)

    Temeyer, Kevin B; Tuckow, Alexander P; Brake, Danett K; Li, Andrew Y; Pérez de León, Adalberto A

    2013-03-25

    Acetylcholinesterase (AChE) is the biochemical target of organophosphate (OP) and carbamate pesticides for invertebrates, vertebrate nerve agents, and AChE inhibitors used to reduce effects of Alzheimer's disease. Organophosphate pesticides (OPs) are widely used to control blood-feeding arthropods, including biting flies and ticks. However, resistance to OPs in pests affecting animal and human health has compromised control efficacy. OP resistance often results from mutations producing an OP-insensitive AChE. Our studies have demonstrated production of OP-insensitive AChEs in biting flies and ticks. Complementary DNA (cDNA) sequences encoding AChEs were obtained for the horn fly, stable fly, sand fly, and the southern cattle tick. The availability of cDNA sequences enables the identification of mutations, expression and characterization of recombinant proteins, gene silencing for functional studies, as well as in vitro screening of novel inhibitors. The southern cattle tick expresses at least three different genes encoding AChE in their synganglion, i.e. brain. Gene amplification for each of the three known cattle tick AChE genes and expression of multiple alleles for each gene may reduce fitness cost associated with OP-resistance. AChE hydrolyzes the neurotransmitter, acetylcholine, but may have additional roles in physiology and development. The three cattle tick AChEs possess significantly different biochemical properties, and are expressed in neural and non-neural tissues, which suggest separation of structure and function. The remarkable complexity of AChEs in ticks suggested by combining genomic data from Ixodes scapularis with our genetic and biochemical data from Rhipicephalus microplus is suggestive of previously unknown gene duplication and diversification. Comparative studies between invertebrate and vertebrate AChEs could enhance our understanding of structure-activity relationships. Research with ticks as a model system offers the opportunity to

  19. FliO Regulation of FliP in the Formation of the Salmonella enterica Flagellum

    Science.gov (United States)

    Barker, Clive S.; Meshcheryakova, Irina V.; Kostyukova, Alla S.; Samatey, Fadel A.

    2010-01-01

    The type III secretion system of the Salmonella flagellum consists of 6 integral membrane proteins: FlhA, FlhB, FliO, FliP, FliQ, and FliR. However, in some other type III secretion systems, a homologue of FliO is apparently absent, suggesting it has a specialized role. Deleting the fliO gene from the chromosome of a motile strain of Salmonella resulted in a drastic decrease of motility. Incubation of the ΔfliO mutant strain in motility agar, gave rise to pseudorevertants containing extragenic bypass mutations in FliP at positions R143H or F190L. Using membrane topology prediction programs, and alkaline phosphatase or GFPuv chimeric protein fusions into the FliO protein, we demonstrated that FliO is bitopic with its N-terminus in the periplasm and C-terminus in the cytoplasm. Truncation analysis of FliO demonstrated that overexpression of FliO43–125 or FliO1–95 was able to rescue motility of the ΔfliO mutant. Further, residue leucine 91 in the cytoplasmic domain was identified to be important for function. Based on secondary structure prediction, the cytoplasmic domain, FliO43–125, should contain beta-structure and alpha-helices. FliO43–125-Ala was purified and studied using circular dichroism spectroscopy; however, this domain was disordered, and its structure was a mixture of beta-sheet and random coil. Coexpression of full-length FliO with FliP increased expression levels of FliP, but coexpression with the cytoplasmic domain of FliO did not enhance FliP expression levels. Overexpression of the cytoplasmic domain of FliO further rescued motility of strains deleted for the fliO gene expressing bypass mutations in FliP. These results suggest FliO maintains FliP stability through transmembrane domain interaction. The results also demonstrate that the cytoplasmic domain of FliO has functionality, and it presumably becomes structured while interacting with its binding partners. PMID:20941389

  20. FliO regulation of FliP in the formation of the Salmonella enterica flagellum.

    Directory of Open Access Journals (Sweden)

    Clive S Barker

    2010-09-01

    Full Text Available The type III secretion system of the Salmonella flagellum consists of 6 integral membrane proteins: FlhA, FlhB, FliO, FliP, FliQ, and FliR. However, in some other type III secretion systems, a homologue of FliO is apparently absent, suggesting it has a specialized role. Deleting the fliO gene from the chromosome of a motile strain of Salmonella resulted in a drastic decrease of motility. Incubation of the ΔfliO mutant strain in motility agar, gave rise to pseudorevertants containing extragenic bypass mutations in FliP at positions R143H or F190L. Using membrane topology prediction programs, and alkaline phosphatase or GFPuv chimeric protein fusions into the FliO protein, we demonstrated that FliO is bitopic with its N-terminus in the periplasm and C-terminus in the cytoplasm. Truncation analysis of FliO demonstrated that overexpression of FliO₄₃-₁₂₅ or FliO₁-₉₅ was able to rescue motility of the ΔfliO mutant. Further, residue leucine 91 in the cytoplasmic domain was identified to be important for function. Based on secondary structure prediction, the cytoplasmic domain, FliO₄₃-₁₂₅, should contain beta-structure and alpha-helices. FliO₄₃-₁₂₅-Ala was purified and studied using circular dichroism spectroscopy; however, this domain was disordered, and its structure was a mixture of beta-sheet and random coil. Coexpression of full-length FliO with FliP increased expression levels of FliP, but coexpression with the cytoplasmic domain of FliO did not enhance FliP expression levels. Overexpression of the cytoplasmic domain of FliO further rescued motility of strains deleted for the fliO gene expressing bypass mutations in FliP. These results suggest FliO maintains FliP stability through transmembrane domain interaction. The results also demonstrate that the cytoplasmic domain of FliO has functionality, and it presumably becomes structured while interacting with its binding partners.

  1. Visceral leishmaniasis in border areas: clustered distribution of phlebotomine sand flies in Clorinda, Argentina

    Directory of Open Access Journals (Sweden)

    Oscar D Salomón

    2009-08-01

    Full Text Available Three years after the first report of Lutzomyia longipalpis in Clorinda, Argentina, a border city near Asunción, Paraguay, the city was surveyed again. Lu. longipalpis was found clustered in the same neighbourhoods in 2007 as in 2004, even though the scattered distribution of canine visceral leishmaniasis was more related to the traffic of dogs through the border.

  2. Visceral leishmaniasis in border areas: clustered distribution of phlebotomine sand flies in Clorinda, Argentina.

    Science.gov (United States)

    Salomón, Oscar D; Quintana, María G; Bruno, Mario R; Quiriconi, Ricardo V; Cabral, Viviana

    2009-08-01

    Three years after the first report of Lutzomyia longipalpis in Clorinda, Argentina, a border city near Asunción, Paraguay, the city was surveyed again. Lu. longipalpis was found clustered in the same neighbourhoods in 2007 as in 2004, even though the scattered distribution of canine visceral leishmaniasis was more related to the traffic of dogs through the border.

  3. Mild-Vectolysis: A nondestructive DNA extraction method for vouchering sand flies and mosquitoes

    Science.gov (United States)

    Nondestructive techniques allow the isolation of genomic DNA, without damaging the morphological features of the specimens. Though such techniques are available for numerous insect groups, they have not been applied to any member of the medically important families of mosquitoes (Diptera: Culicidae)...

  4. Discovery of Diurnal Resting Sites of Phlebotomine Sand Flies in a Village in Southern Egypt

    Science.gov (United States)

    2008-01-01

    e.g., Leishmania spp., Bartonella bacilliformis, and several arboviruses. Management of phleboto- mine populations has been difficult because little is...Hanafi HA, Beavers GM, Dykstra EA. 2001. New record of Phlebotomus sergenti, the vector of Leish- mania tropica , in the southern Nile valley of Egypt. J

  5. Phlebotomine sand flies (Diptera: Psychodidae: Phlebotominae) of Alagoas state, northeast of Brazil.

    Science.gov (United States)

    Andrade Filho, José D; Brazil, Reginaldo P

    2009-01-01

    The phlebotomine sandflies of the state of Alagoas are poorly known, with more than 40 years since the last report on sandflies in the state. In here, Psathyromyia brasiliensis (Costa Lima), Micropygomyia quinquefer (Dyar,) and Evandromyia termitophila (Martins, Falcão & Silva) are registered for the first time in Alagoas. This report increases to nine the number of species collected in the state, including Lutzomyia longipalpis (Lutz & Neiva), Migonemyia migonei (França), Nyssomyia whitmani (Antunes & Coutinho) and Nyssomyia intermedia (Lutz & Neiva), all vectors of Leishmania in Brazil.

  6. Imidacloprid as a Potential Agent for the Systemic Control of Sand Flies

    Science.gov (United States)

    2011-03-01

    reporting burden for the collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching ...2007a, 2007b, 2008) demonstrated the feed-through effectiveness of several insecticides (diflubenzuron, novaluron, and ivermectin ) in...Diptera : Psychodidae). J. Med. Entomol. 44: 171-174. Mascari, T.M., M.A. Mitchell, E.D. Rowton, and L.D. Foil. 2008. Ivermectin as a

  7. Ecological and Control Techniques for Sand Flies (Diptera: Psychodidae) Associated with Rodent Reservoirs of Leishmaniasis

    Science.gov (United States)

    2013-09-12

    Nutrition International, Brentwood, MO). Samples of the diets and the feces of rabbits and hamsters were collected, air-dried at room temperature ...leishman- iasis in Iranian soldiers. J Clin Pharm Ther 28: 175–178. 4. Feliciangeli MD (2004) Natural breeding places of phlebotomine sandflies . Med...Psychodidae). Bull Soc Pathol Exot 106:54– 58. 16. Singh R, Lal S, Saxena VK, Breeding ecology of visceral leishmaniasis vector sandfly in Bihar state of

  8. Dissociation between vasodilation and Leishmania infection-enhancing effects of sand fly saliva and maxadilan

    Directory of Open Access Journals (Sweden)

    Fábio Castro-Sousa

    2001-10-01

    Full Text Available In this study, the ability of maxadilan and Lutzomyia longipalpis salivary gland lysate to enhance the infection of CBA mice by Leishmania major and of BALB/c mice by L. braziliensis was tested. No difference was observed between sizes of lesion in CBA mice infected with L. major and treated or not with salivary gland lysate or maxadilan, although they were injected in concentrations that induced cutaneous vasodilation. Although parasites were more frequently observed in foot pads and spleens of animals treated with maxadilan than in the animals treated with salivary gland lysate or saline, the differences were small and not statistically significant. The lesions in BALB/c mice infected with L. braziliensis and treated with maxadilan were slightly larger than in animals that received Leishmania alone. Such differences disappeared 14 weeks after infection, and were statistically significant only in one of two experiments.

  9. Detection of Bartonella bacilliformis by Real-Time PCR in Naturally Infected Sand Flies

    Science.gov (United States)

    2007-11-02

    infectious disease is found commonly in medically-underserved communities in the Andes Mountains regions of Peru, Ecuador and Colombia (Alexander...bartonellosis in Ecuador and Colombia, Am. J. Trop. Med. Hyg. 52:354-359. Alexander B. and Marolli M. 2003. Control of phlebotomine sandflies...Med Vet Entomol. Mar; 17(1): 1-18. Barbian K.D. and Minnick M.F. 2000. A bacteriophage-like particle from Bartonella bacilliformis. Microbiology

  10. Sand Flies (Diptera: Psychodidae: Phlebotominae): Significance, Surveillance, and Control in Contingency Operations

    Science.gov (United States)

    2015-01-01

    Vietnam, Laos and Indonesia . Bionomics: This species is a competent vector of Leishmania donovani, the agent of classic VL. In parts of India...abdomen and squeeze the gut out of the abdomen like you would toothpaste out of a tube. Often the diverticulum (crop) breaks off and you must “ fish ...are scarce or absent. An ATSB bait station with boric acid has been registered with EPA but has not yet been marketed in the USA, although it is

  11. New Insecticides and Repellents For Use on Mosquitoes and Sand Flies

    Science.gov (United States)

    The major emphasis of our research is on the discovery and development of new insecticides for personal protection. The insecticide discovery effort involves structure-activity modeling to correlate molecular structure and electronic properties with repellent and/or insecticidal activity. Models a...

  12. Aerodynamics of the Smallest Flying Insects

    CERN Document Server

    Miller, Laura A; Hedrick, Ty; Robinson, Alice; Santhanakrishnan, Arvind; Lowe, Audrey

    2011-01-01

    We present fluid dynamics videos of the flight of some of the smallest insects including the jewel wasp, \\textit{Ampulex compressa}, and thrips, \\textit{Thysanoptera} spp. The fruit fly, \\textit{Drosophila melanogaster}, is large in comparison to these insects. While the fruit fly flies at $Re \\approx 120$, the jewel wasp flies at $Re \\approx 60$, and thrips flies at $Re \\approx 10$. Differences in the general structures of the wakes generated by each species are observed. The differences in the wakes correspond to changes in the ratio of lift forces (vertical component) to drag forces (horizontal component) generated.

  13. Critical State of Sand Matrix Soils

    Directory of Open Access Journals (Sweden)

    Aminaton Marto

    2014-01-01

    Full Text Available The Critical State Soil Mechanic (CSSM is a globally recognised framework while the critical states for sand and clay are both well established. Nevertheless, the development of the critical state of sand matrix soils is lacking. This paper discusses the development of critical state lines and corresponding critical state parameters for the investigated material, sand matrix soils using sand-kaolin mixtures. The output of this paper can be used as an interpretation framework for the research on liquefaction susceptibility of sand matrix soils in the future. The strain controlled triaxial test apparatus was used to provide the monotonic loading onto the reconstituted soil specimens. All tested soils were subjected to isotropic consolidation and sheared under undrained condition until critical state was ascertain. Based on the results of 32 test specimens, the critical state lines for eight different sand matrix soils were developed together with the corresponding values of critical state parameters, M, λ, and Γ. The range of the value of M, λ, and Γ is 0.803–0.998, 0.144–0.248, and 1.727–2.279, respectively. These values are comparable to the critical state parameters of river sand and kaolin clay. However, the relationship between fines percentages and these critical state parameters is too scattered to be correlated.

  14. Critical state of sand matrix soils.

    Science.gov (United States)

    Marto, Aminaton; Tan, Choy Soon; Makhtar, Ahmad Mahir; Kung Leong, Tiong

    2014-01-01

    The Critical State Soil Mechanic (CSSM) is a globally recognised framework while the critical states for sand and clay are both well established. Nevertheless, the development of the critical state of sand matrix soils is lacking. This paper discusses the development of critical state lines and corresponding critical state parameters for the investigated material, sand matrix soils using sand-kaolin mixtures. The output of this paper can be used as an interpretation framework for the research on liquefaction susceptibility of sand matrix soils in the future. The strain controlled triaxial test apparatus was used to provide the monotonic loading onto the reconstituted soil specimens. All tested soils were subjected to isotropic consolidation and sheared under undrained condition until critical state was ascertain. Based on the results of 32 test specimens, the critical state lines for eight different sand matrix soils were developed together with the corresponding values of critical state parameters, M, λ, and Γ. The range of the value of M, λ, and Γ is 0.803-0.998, 0.144-0.248, and 1.727-2.279, respectively. These values are comparable to the critical state parameters of river sand and kaolin clay. However, the relationship between fines percentages and these critical state parameters is too scattered to be correlated.

  15. Adsorption of dyes on Sahara desert sand.

    Science.gov (United States)

    Varlikli, Canan; Bekiari, Vlasoula; Kus, Mahmut; Boduroglu, Numan; Oner, Ilker; Lianos, Panagiotis; Lyberatos, Gerasimos; Icli, Siddik

    2009-10-15

    Sahara desert sand (SaDeS) was employed as a mineral sorbent for retaining organic dyes from aqueous solutions. Natural sand has demonstrated a strong affinity for organic dyes but significantly lost its adsorption capacity when it was washed with water. Therefore, characterization of both natural and water washed sand was performed by XRD, BET, SEM and FTIR techniques. It was found that water-soluble kyanite, which is detected in natural sand, is the dominant factor affecting adsorbance of cationic dyes. The sand adsorbs over 75% of cationic dyes but less than 21% for anionic ones. Among the dyes studied, Methylene Blue (MB) demonstrated the strongest affinity for Sahara desert sand (Q(e)=11.98 mg/g, for initial dye solution concentration 3.5 x 10(-5)mol/L). The effects of initial dye concentration, the amount of the adsorbent, the temperature and the pH of the solution on adsorption capacity were tested by using Methylene Blue as model dye. Pseudo-first-order, pseudo-second-order and intraparticle diffusion models were applied. It was concluded that adsorption of Methylene Blue on Sahara desert sand followed pseudo-second order kinetics. Gibbs free energy, enthalpy change and entropy change were calculated and found -6411 J/mol, -30360 J/mol and -76.58 J/mol K, respectively. These values indicate that the adsorption is an exothermic process and has a spontaneous nature at low temperatures.

  16. Study on Machining Properties of Eucalyptus urophylla × E. Grandis: Ⅰ. Planing and Sanding Properties

    Institute of Scientific and Technical Information of China (English)

    HOU Xinyi; JIANG Xiaomei; GAO Jianmin; YIN Yafang

    2006-01-01

    The research method in this paper is based on the standard of American Society for Testing and Materials (ASTM), Planing and sanding are selected to study the machining properties of E. Urophylla × E. Grandis plantation wood. Moreover, the reasons for machining defects are analyzed. The results show E. Urophylla × E. Grandis planted in south China is a good species with a great potential for solid wood utilization.

  17. Invasive plants on disturbed Korean sand dunes

    Science.gov (United States)

    Kim, Kee Dae

    2005-01-01

    The sand dunes in coastal regions of South Korea are important ecosystems because of their small size, the rare species found in this habitat, and the beautiful landscapes they create. This study investigated the current vegetative status of sand dunes on three representative coasts of the Korean peninsula, and on the coasts of Cheju Island, and assessed the conditions caused by invasive plants. The relationships between the degree of invasion and 14 environmental variables were studied. Plots of sand dunes along line transects perpendicular to the coastal lines were established to estimate vegetative species coverage. TWINSPAN (Two-Way Indicator Species Analysis), CCA (Canonical Correspondence Analysis), and DCCA (Detrended Canonical Correspondence Analysis) were performed to classify communities on sand dunes and assess species composition variation. Carex kobomugi, Elymus mollis, and Vitex rotundifolia were found to be the dominant species plotted on the east, the west, and the peripheral coasts of Cheju Island, respectively. Vegetation on the south coast was totally extinct. The 19 communities, including representative C. kobomugi, C. kobomugi- Ixeris repens, C. kobomugi- Oenothera biennis, E. mollis, Lolium multiflorum- Calystegia soldanella, and V. rotundifolia- C. kobomugi, were all classified according to TWINSPAN. Oenothera biennis and L. multiflorum were exotics observed within these native communities. CCA showed that invasive native and exotic species distribution was segregated significantly, according to disturbance level, exotic species number, gravel, sand and silt contents, as well as vegetation size. It further revealed that human disturbance can strongly favor the settlement of invasive and exotic species. Restoration options to reduce exotic plants in the South Korean sand dune areas were found to be the introduction of native plant species from one sand dune into other sand dune areas, prohibition of building and the introduction of exotic

  18. Formation mechanism of cracks in saturated sand

    Institute of Scientific and Technical Information of China (English)

    Xiaobing Lu; Zhemin Zheng; Yongren Wu

    2006-01-01

    The formation mechanism of "water film" (or crack) in saturated sand is analyzed theoretically and numerically.The theoretical analysis shows that there will be no stable "water film" in the saturated sand if the strength of the skeleton is zero and no positions are choked.It is shown by numerical simulation that stable water films initiate and grow if the choking state keeps unchanged once the fluid velocities decrease to zero in the liquefied sand column.The developments of "water film" based on the model presented in this paper are compared with experimental results.

  19. Lund Sand No 0:part 2

    OpenAIRE

    Ibsen, Lars Bo; Jakobsen, Finn Rosendal

    1996-01-01

    During the last 15 years the Geotechnical Engineering Group (GEG) at Aalborg University has performed triaxial tests with a sand called Lund No 0. Lund No 0 is a graded sand from a gravel pit near Horsens in Denmark. For the classification of the sand the following tests have been performed: Sieve test, Grain density, ds, Maximum, emax, and minimum, emin, void ratio. The strength parameters of Lund No 0 are detennined by some drained and undrained triaxial tests in the Danish Triaxial Cell. T...

  20. Lund Sand No 0:part 1

    OpenAIRE

    Ibsen, Lars Bo; Jakobsen, Finn Rosendal

    1996-01-01

    During the last 15 years the Geotechnical Engineering Group (GEG) at Aalborg University has performed triaxial tests with a sand called Lund No 0. Lund No 0 is a graded sand from a gravel pit near Horsens in Denmark. For the classification of the sand the following tests have been performed: Sieve test, Grain density, ds, Maximum, emax, and minimum, emin, void ratio. The strength parameters of Lund No 0 are detennined by some drained and undrained triaxial tests in the Danish Triaxial Cell. T...

  1. Biodegradable materials as foundry moulding sands binders

    Directory of Open Access Journals (Sweden)

    K. Major - Gabryś

    2015-07-01

    Full Text Available The aim of this article is to show the possibility of using biodegradable materials as part of the composition of foundry moulding and core sand binders. Research shows that moulding sands with biodegradable materials selected as binders are not only less toxic but are also better suited to mechanical reclamation than moulding sands with phenol-furfuryl resin. The use of biodegradable materials as additives to typical synthetic resins can result in their decreased toxicity and improved ability to reclamation as well as in accelerated biodegradation of binding material leftovers of mechanical reclamation.

  2. Binocular interactions underlying the classic optomotor responses of flying flies

    Directory of Open Access Journals (Sweden)

    Brian J Duistermars

    2012-02-01

    Full Text Available In response to imposed course deviations, the fast optomotor reactions of animals reduce motion blur and facilitate the maintenance of stable body posture. In flies, the monocular front-to-back (progressive and back-to-front (regressive visual motion components generated by horizontal rotation are selectively encoded, respectively, by homo and heterolateral motion sensitive circuits in the third optic ganglion, the lobula plate. To investigate the strength of such inter-ocular interactions and their role in compensatory sensory-motor transformations, we utilize a virtual reality flight simulator to record optomotor reactions by tethered flying flies in response to imposed binocular and monocular visual rotation. With stimulus parameters generating large contrast insensitive optomotor responses to binocular rotation, we find that responses to monocular progressive motion are larger than those to panoramic rotation but contrast sensitive. Conversely, responses to monocular regressive motion are slower than those to rotation and peak at the lowest tested contrast. Together our results suggest that contrast insensitive optomotor responses to binocular rotation result from the dynamic interplay of contralateral inhibitory as well as excitatory circuit interactions and serve to maintain a stable optomotor equilibrium across a range of visual contrasts.

  3. Watching Faults Grow in Sand

    Science.gov (United States)

    Cooke, M. L.

    2015-12-01

    Accretionary sandbox experiments provide a rich environment for investigating the processes of fault development. These experiments engage students because 1) they enable direct observation of fault growth, which is impossible in the crust (type 1 physical model), 2) they are not only representational but can also be manipulated (type 2 physical model), 3) they can be used to test hypotheses (type 3 physical model) and 4) they resemble experiments performed by structural geology researchers around the world. The structural geology courses at UMass Amherst utilize a series of accretionary sandboxes experiments where students first watch a video of an experiment and then perform a group experiment. The experiments motivate discussions of what conditions they would change and what outcomes they would expect from these changes; hypothesis development. These discussions inevitably lead to calculations of the scaling relationships between model and crustal fault growth and provide insight into the crustal processes represented within the dry sand. Sketching of the experiments has been shown to be a very effective assessment method as the students reveal which features they are analyzing. Another approach used at UMass is to set up a forensic experiment. The experiment is set up with spatially varying basal friction before the meeting and students must figure out what the basal conditions are through the experiment. This experiment leads to discussions of equilibrium and force balance within the accretionary wedge. Displacement fields can be captured throughout the experiment using inexpensive digital image correlation techniques to foster quantitative analysis of the experiments.

  4. Effect of Additives on Green Sand Molding Properties using Design of Experiments and Taguchi's Quality Loss Function - An Experimental Study

    Science.gov (United States)

    Desai, Bhagyashree; Mokashi, Pavani; Anand, R. L.; Burli, S. B.; Khandal, S. V.

    2016-09-01

    The experimental study aims to underseek the effect of various additives on the green sand molding properties as a particular combination of additives could yield desired sand properties. The input parameters (factors) selected were water and powder (Fly ash, Coconut shell and Tamarind) in three levels. Experiments were planned using design of experiments (DOE). On the basis of plans, experiments were conducted to understand the behavior of sand mould properties such as compression strength, shear strength, permeability number with various additives. From the experimental results it could be concluded that the factors have significant effect on the sand properties as P-value found to be less than 0.05 for all the cases studied. The optimization based on quality loss function was also performed. The study revealed that the quality loss associated with the tamarind powder was lesser compared to other additives selected for the study. The optimization based on quality loss function and the parametric analysis using ANOVA suggested that the tamarind powder of 8 gm per Kg of molding sand and moisture content of 7% yield better properties to obtain sound castings.

  5. An airborne assessment of atmospheric particulate emissions from the processing of Athabasca oil sands

    Directory of Open Access Journals (Sweden)

    S. G. Howell

    2013-08-01

    Full Text Available During the Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS campaign, two NASA research aircraft, a DC-8 and a P-3B, were outfitted with extensive trace gas (the DC-8 and aerosol (both aircraft instrumentation. Each aircraft spent about a half hour sampling air around the oil sands mining and upgrading facilities near Ft. McMurray, Alberta, Canada. The DC-8 circled the area, while the P-3B flew directly over the upgrading plants, sampling close to the exhaust stacks, then headed downwind to monitor the aerosol as it aged. At short range, the plume from the oil sands is a complex mosaic of freshly nucleated ultrafine particles from a SO2 and NO2-rich plume, fly ash and soot from industrial processes, and dust from dirt roads and mining operations. Shortly downwind, organic aerosol appears in quantities that rival SO4=, either as volatile organic vapors condense or as they react with the H2SO4. The DC-8 pattern allowed us to integrate total flux from the oil sands facilities within about a factor of two uncertainty that spanned values consistent with 2008 estimates from reported SO2 and NO2 emissions. In contrast, CO fluxes exceeded reported regional emissions, due either to variability in production or sources missing from the emissions inventory. The conversion rate of SO2 to aerosol SO4= of ~6% per hour is consistent with earlier reports, though OH concentrations are insufficient to accomplish this. Other oxidation pathways must be active. Altogether, organic aerosol and black carbon emissions from the oil sands operations are small compared with the forest fires present in the region during the summer. The oil sands do contribute significant sulfate and exceed fire production of SO2 by an order of magnitude.

  6. Effect of Chromite-Silica Sands Characteristics on Performance of Ladle Filler Sands for Continuous Casting

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Free opening rate is mainly determined by the performance of the ladle filler sand. High free opening rates of ladles are required in steel making to improve steel quality. Chromite ladle filler sands are one of the most widely used ladle filler sand. Several operative variables and materials characteristics affect the performance of the sands. Three sets of chromite ladle filler sands were selected and researches were focused on the sintering hehaviour and per- formance of the sands under operative conditions. The effect of particle size distribution on sintering, microstruc- ture, flowability, and permeability were presented. In all cases, the particle size varies from 0.1 to 1.5 mm corre- sponding to free flowing powders. One of the samples has higher permeability factor in comparison with others due to low particle size distribution. The other sample presents very good free opening due to its very good flowability and permeability factor.

  7. "Fly me to the moon"

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ China's first lunar probe Chang'e-I, named after a mythical Chinese goddess who, according to legend, made her home on the moon, blasted off on 24 October from the Xichang Satellite Launch Center in the southwestern province of Sichuan. In addition to making the dream cherished by Chinese people to fly to the moon come true, it is the first step into China's ambitious threestage moon mission, marking a new milestone in the country's space exploration history.

  8. Electrodialytic treatment of fly ash

    DEFF Research Database (Denmark)

    Jensen, Pernille Erland; Pedersen, Anne Juul; Kirkelund, Gunvor Marie;

    Heavy metals are removed from the fly ashes by an electrodialytic treatment with the aim of up-grading the ashes for reuse in stead of disposal in landfill.A great potential for upgrading of bio- and waste incineration ashes by electrodialytic treatment exists. In the future, the applicability...... of the treated products for reuse in construction or farming sectors should be explored further, as should the possibility of recycling of valuable, extracted elements in the metallurgical industry....

  9. Notes on flying and dying.

    Science.gov (United States)

    Meyer, B C

    1983-07-01

    Focused on selected details in the lives and creative works of Samuel Johnson, Edgar Allan Poe, and Houdini, this paper explores a seeming antinomy between claustrophobic annihilation and aviation. At first glance the latter appears as an antidote to the threat of entrapment and death. On a deeper level the distinction fades as the impression arises that in the examples cited, flying may represent an unconscious expression of a wish for death and ultimate reunion.

  10. Fly Ash as a Time Marker for Anthropocene Alluvial Sedimentation

    Science.gov (United States)

    Bettis, E. A., III; Grimley, D. A.; Anders, A. M.; Bates, B.; Hannan, E.

    2014-12-01

    Human land use has transformed the landscapes, ecosystems and hydrology of the North American Midcontinent. One widespread impact of this transformation is increased runoff and accelerated soil erosion, which, along with direct human channel modifications and artificial drainage, have dramatically altered hydrologic and ecological conditions in streams and rivers with far-reaching results. A legacy of this change in streams and rivers is preserved on floodplains throughout the region in sediment known as post-settlement alluvium (PSA). Documenting the spatial and temporal pattern of historic floodplain sedimentation in the drainage network is part of a larger effort to understand decadal and century-scale sediment routing through the drainage system and the role of floodplain sedimentation in carbon sequestration. Fly ash, a product of high-temperature coal combustion, began to accumulate on the landscape in the early historic period (c.a.1840-1850 in Iowa and Illinois) as coal-burning technology such as steam engines came into use after 1850; prior to which no source of fly ash was present. Release of fly ash from coal burning in power plants and steam locomotives likely peaked in the early-mid 20th century. Fly ash particles (~ 1 to 10 % magnetic) are identified by their spheroidal shape and range in size from coarse clay to silt (~1-63µ). By identifying the percentage of fly ash spheroids in the magnetic separate (10 - 60µ size range) of a soil or sediment profile, the pre-fly ash Historic surface could be discerned. Application of this technique in selected localities in eastern Iowa (Clear Creek drainage) and central Illinois (Sangamon River drainage) resulted in successful demarcation of the PSA contact in areas where the boundary was physically evident. Bolstered by this success we were able to confidently demark the PSA contact in other settings where the boundary was not as physically evident. This relatively easy to implement, inexpensive tool will

  11. Bioaugmentation of flow-through sand filters

    DEFF Research Database (Denmark)

    Samuelsen, Elin Djurhuus

    Global applications of pesticides in agricultural production have led to the detection of trace amounts of pesticides in groundwater resources in levels exceeding the EU threshold limit for drinking water of 0.1 µg L-1. Pesticide-polluted groundwater may be remediated by inoculating waterworks sand...... for degradation performances in flow-through sand columns, with the aim of identifying a suitable inoculant strain for future environmental applications. Another aim was to identify a suitable genetic marker to monitor phenoxy acid degradation in strain Sphingobium sp. PM2. We were not able to link motility...... and biofilm formation to the strains´ ability to adhere to sand. Nevertheless, a correlation was found between cell surface hydrophobicity and adhesion and overall degradation performances in flow-through sand columns. We identified S phingobium sp. PM2 as a promising inoculant strain, displaying efficient...

  12. Petrophysical Analysis of Oil Sand in Athabasca

    Science.gov (United States)

    cheong, S.; Lee, H.

    2013-12-01

    Oil sands are the major unconventional energy sources which have great reserves in Alberta, Canada. Recovery techniques such as CSS (Cyclic Steam Stimulation) and SAGD (Steam Assisted Gravity Drainage) enabled to develop deeper bitumen about several hundred meter depth. Before applying CSS and SAGD, reservoir heterogeneity of mud barriers or shale breccias should be clarified to establish injection and production wells successfully. We conducted the integrated petro-physical analysis for oil sands deposits in Athabasca by correlating well logs with seismic data. From 33 well logs and 3D seismic, we have made P-wave impedance by recursive inversion. Target formations of our analysis were the top of Wabiskaw member. Using inverted impedance and multi-attributes, porosity volume was derived at a target depth. Porosity of time slice 375 ms ranged 20 ~ 40 % stretching porous sand body from NE to SW direction. Characteristics of porosity distribution may be useful to design optimum oil sands recovery in Athabasca.

  13. Carbon cycle: New pathways in the sand

    Science.gov (United States)

    Rao, Alexandra

    2017-01-01

    Organic carbon decomposition in anoxic marine sediments was thought to be dominated by bacteria, but experimental data and microbial culture studies now show that microalgae buried in coastal sands may also play an important role in carbon turnover.

  14. Sand Lake WMD vegetation mapping project update

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Final report on the vegetation mapping project at Sand Lake Wetland Management District. This project is being completed by the use of SPRING software and ground...

  15. Treating tar sands formations with dolomite

    Energy Technology Data Exchange (ETDEWEB)

    Vinegar, Harold J.; Karanikas, John Michael

    2010-06-08

    Methods for treating a tar sands formation are described herein. The tar sands formation may include dolomite and hydrocarbons. Methods may include providing heat at less than the decomposition temperature of dolomite from one or more heaters to at least a portion of the formation. At least some of the hydrocarbon fluids are mobilized in the formation. At least some of the hydrocarbon fluids may be produced from the formation.

  16. Laboratory evaluation of selected tar sand asphalts

    Energy Technology Data Exchange (ETDEWEB)

    Button, J.W.; Epps, J.A.; Gallaway, B.M.

    1980-12-01

    Three tar sand asphalts of similar grades prepared from one syncrude by three different refining methods were characterized by tests commonly used to specify paving asphalts together with certain special tests. Asphalt-aggregate mixtures were prepared using these asphalts and tested in the laboratory to determine strength stiffness stability, tensile properties, temperature effects and water susceptibility. Comparison of the tar sand asphalt properties to conventional petroleum asphalt properties reveal no striking differences.

  17. CRADE OF SAND AND DUST STORM WEATHER

    Institute of Scientific and Technical Information of China (English)

    Niu Ruoyun; Tian Cuiying; Bi Baogui; Yang Keming; Wang Youheng; Tuo Ya; Ding Haifang; Zhang Tairen

    2011-01-01

    Background Sand and dust storm,as one of the main disastrous weathers that affect northern China,not only affect the people health and normal life,but cause the short-term climatic changes due to the direct and indirect radiation of the earth-atmosphere system through the dust floating in the sky.The sand end dust weather and its potential harm on the national economy,ecological environment,social activities and other aspects have aroused worldwide concern.

  18. Identifying glass compositions in fly ash

    Directory of Open Access Journals (Sweden)

    Katherine eAughenbaugh

    2016-01-01

    Full Text Available In this study, four Class F fly ashes were studied with a scanning electron microscope; the glassy phases were identified and their compositions quantified using point compositional analysis with k-means clustering and multispectral image analysis. The results showed that while the bulk oxide contents of the fly ashes were different, the four fly ashes had somewhat similar glassy phase compositions. Aluminosilicate glasses (AS, calcium aluminosilicate glasses (CAS, a mixed glass, and, in one case, a high iron glass were identified in the fly ashes. Quartz and iron crystalline phases were identified in each fly ash as well. The compositions of the three main glasses identified, AS, CAS, and mixed glass, were relatively similar in each ash. The amounts of each glass were varied by fly ash, with the highest calcium fly ash containing the most of calcium-containing glass. Some of the glasses were identified as intermixed in individual particles, particularly the calcium-containing glasses. Finally, the smallest particles in the fly ashes, with the most surface area available to react in alkaline solution, such as when mixed with portland cement or in alkali-activated fly ash, were not different in composition than the large particles, with each of the glasses represented. The method used in the study may be applied to a fly ash of interest for use as a cementing material in order to understand its potential for reactivity.

  19. Analysis of sand particles' lift-off and incident velocities in wind-blown sand flux

    Institute of Scientific and Technical Information of China (English)

    Tian-Li Bo; Xiao-Jing Zheng; Shao-Zhen Duan; Yi-Rui Liang

    2013-01-01

    In the research of windblown sand movement,the lift-off and incident velocities of saltating sand particles play a significant role in bridging the spatial and temporal scales from single sand particle's motion to windblown sand flux.In this paper,we achieved wind tunnel measurements of the movement of sand particles near sand bed through improving the wind tunnel experimental scheme of paticle image velocimetry (PIV) and data processing method.And then the influence of observation height on the probability distributions of lift-off and incident velocities of sand particles was analyzed.The results demonstrate that the observation height has no obvious influence on the distribution pattern of the lift-off and incident velocities of sand particles,i.e.,the probability distribution of horizontal and vertical velocities of lift-off and incident sand particles follow a Gaussian distribution and a negative exponential distribution,respectively.However,it influences the center of the Gaussian distribution,the decay constant and the amplitude of the negative exponential distribution.

  20. Discrete particle simulation of mixed sand transport

    Institute of Scientific and Technical Information of China (English)

    Fengjun Xiao; Liejin Guo; Debiao Li; Yueshe Wang

    2012-01-01

    An Eulerian/Lagrangian numerical simulation is performed on mixed sand transport.Volume averaged Navier-Stokes equations are solved to calculate gas motion,and particle motion is calculated using Newton's equation,involving a hard sphere model to describe particle-to-particle and particle-to-wall collisions.The influence of wall characteristics,size distribution of sand particles and boundary layer depth on vertical distribution of sand mass flux and particle mean horizontal velocity is analyzed,suggesting that all these three factors affect sand transport at different levels.In all cases,for small size groups,sand mass flux first increases with height and then decreases while for large size groups,it decreases exponentially with height and for middle size groups the behavior is in-between.The mean horizontal velocity for all size groups well fits experimental data,that is,increasing logarithmically with height in the middle height region.Wall characteristics greatly affects particle to wall collision and makes the flat bed similar to a Gobi surface and the rough bed similar to a sandy surface.Particle size distribution largely affects the sand mass flux and the highest heights they can reach especially for larger particles.

  1. Layers, Landslides, and Sand Dunes

    Science.gov (United States)

    2003-01-01

    [figure removed for brevity, see original site] Released 27 October 2003This image shows the northern rim of one of the Valles Marineris canyons. Careful inspection shows many interesting features here. Note that the spurs and gullies in the canyon wall disappear some distance below the top of the canyon wall, indicating the presence of some smooth material here that weathers differently from the underlying rocks. On the floor of the canyon, there are remains from a landslide that came hurtling down the canyon wall between two spurs. Riding over the topography of the canyon floor are many large sand dunes, migrating generally from the lower right to upper left.Image information: VIS instrument. Latitude -14.1, Longitude 306.7 East (53.3 West). 19 meter/pixel resolution.Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time. NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  2. Jarosite added concrete along with fly ash: Properties and characteristics in fresh state

    Directory of Open Access Journals (Sweden)

    Priyansha Mehra

    2016-09-01

    Full Text Available This paper presents the results of different properties and characteristics of jarosite added concrete along with fly ash during its fresh state. Jarosite is an industrial by product from zinc manufacturing industry obtained through hydrometallurgical process from its sulphide ore. It has been tried to incorporate jarosite in concrete as sand replacement. Different concrete mixtures have been prepared for three water–cement ratios (0.40, 0.45 and 0.50 and 5 jarosite replacement levels (0, 5, 10, 15, 20 and 25%. Cement has been partially replaced (25% by fly ash in all the concrete mixtures. Density, workability and setting & hardening of fresh concrete has been evaluated and analyzed. Keeping the environmental suitability of concrete in mind, toxicity leaching characteristic potential test has been performed on raw jarosite and concrete samples.

  3. Predicting the occurrence of sand banks in the North Sea

    NARCIS (Netherlands)

    Veen, van der Henriët H.; Hulscher, Suzanne J.M.H.

    2009-01-01

    Sand banks have a wavelength between 1 and 10 km, and they are up to several tens of meters high. Also, sand banks may have an impact on large-scale human activities that take place in the North Sea like sand mining, shipping, offshore wind farms, etc. Therefore, it is important to know where sand b

  4. Alberta's economic development of the Athabasca oil sands

    Science.gov (United States)

    Steinmann, Michael

    innovations to achieve economic oil sands productivity, the oil companies have responded successfully to declining rates of American conventional oil production. With respect to North American hinterlands, implications for development theory center on connections among established and changing political coalitions, capacities for technological innovations, and responses to dynamic world conditions.

  5. Thermal treatment and utilization of Al-rich waste in high calcium fly ash geopolymeric materials

    Science.gov (United States)

    Chindaprasirt, Prinya; Rattanasak, Ubolluk; Vongvoradit, Pimdao; Jenjirapanya, Supichart

    2012-09-01

    The Al-rich waste with aluminium and hydrocarbon as the major contaminant is generated at the wastewater treatment unit of a polymer processing plant. In this research, the heat treatment of this Al-rich waste and its use to adjust the silica/alumina ratio of the high calcium fly ash geopolymer were studied. To recycle the raw Al-rich waste, the waste was dried at 110°C and calcined at 400 to 1000°C. Mineralogical analyses were conducted using X-ray diffraction (XRD) to study the phase change. The increase in calcination temperature to 600, 800, and 1000°C resulted in the phase transformation. The more active alumina phase of active γ-Al2O3 was obtained with the increase in calcination temperature. The calcined Al-rich waste was then used as an additive to the fly ash geopolymer by mixing with high calcium fly ash, water glass, 10 M sodium hydroxide (NaOH), and sand. Test results indicated that the calcined Al-rich waste could be used as an aluminium source to adjust the silica/alumina ratio and the strength of geopolymeric materials. The fly ash geopolymer mortar with 2.5wt% of the Al-rich waste calcined at 1000°C possessed the 7-d compressive strength of 34.2 MPa.

  6. Development of the Gran Desierto sand sea, northwestern Mexico

    Science.gov (United States)

    Blount, Grady; Lancaster, Nicholas

    1990-08-01

    Three major eolian sand populations can be recognized in the Gran Desierto sand sea of northwestern Mexico by using spectral data from the Landsat thematic mapper in conjunction with textural and mineralogical studies of surface sands. Each sand population has distinct textural, mineralogic, and spectral properties that can be related to sand-dune morphology and position with reference to source areas and transport paths of the sands. The oldest eolian sediment in the sand sea was derived from the early to middle Pleistocene Colorado River that flowed through the area of the western Gran Desierto. Subsequent inputs of eolian sands came from the area of the present Colorado River valley and the coast south of the sand sea. The spatial and temporal pattern of eolian deposition in the region has been controlled by Quaternary tectonic and climatic changes, resulting in the episodic input and deposition of sand.

  7. Ultrasonic vocalizations emitted by flying squirrels.

    Directory of Open Access Journals (Sweden)

    Meghan N Murrant

    Full Text Available Anecdotal reports of ultrasound use by flying squirrels have existed for decades, yet there has been little detailed analysis of their vocalizations. Here we demonstrate that two species of flying squirrel emit ultrasonic vocalizations. We recorded vocalizations from northern (Glaucomys sabrinus and southern (G. volans flying squirrels calling in both the laboratory and at a field site in central Ontario, Canada. We demonstrate that flying squirrels produce ultrasonic emissions through recorded bursts of broadband noise and time-frequency structured frequency modulated (FM vocalizations, some of which were purely ultrasonic. Squirrels emitted three types of ultrasonic calls in laboratory recordings and one type in the field. The variety of signals that were recorded suggest that flying squirrels may use ultrasonic vocalizations to transfer information. Thus, vocalizations may be an important, although still poorly understood, aspect of flying squirrel social biology.

  8. Effects of advanced oxidation on green sand properties via iron casting into green sand molds.

    Science.gov (United States)

    Wang, Yujue; Cannon, Fred S; Voigt, Robert C; Komarneni, Sridhar; Furness, J C

    2006-05-01

    The effects of advanced oxidation (AO) processing on the properties of green sand were studied via pouring cast iron into green sand molds. Upon cooling, the green sand molds were autopsied at various distances from the metal-sand interface. Autopsy green sand samples collected from a mold that incorporated AO water were characterized and compared to controlled samples collected from a similar autopsied mold made with conventional tap water (TAP). It was found that the AO processing removed a coating of coal pyrolysis products from the clay surface that typically accumulated on the clay surface. As a result, the AO-conditioned green sand retained 10-15% more active clay as measured bythe standard ultrasonic methylene blue titration than did the TAP-conditioned green sand. The AO processing also nearly doubled the generation of activated carbon from the normalized amount of coal composition of the green sand during the casting process. The AO-enhanced activated carbon generation and the AO-incurred clay surface cleaning provided the AO-conditioned green sand with higher normalized pore volume, and thus higher normalized m-xylene adsorption capacity, i.e., relative to before-metal-pouring conditions. Furthermore, mathematical analysis indicated that the AO-conditioned green sand better retained its important properties after pouring than did the TAP-conditioned green sand. Effectively, this meant after metal pouring, the AO-conditioned sample offered about the same net properties as the TAP-conditioned sample, even though the AO-conditioned sample contained less clay and coal before metal pouring. These results conformed to the full-scale foundry empirical finding that when AO is used, foundries need less makeup clay and coal addition through each casting cycle, and they release less air emissions.

  9. Contribution of laser altimetry images to the geomorphology of the Late Holocene inland drift sands of the European Sand Belt

    NARCIS (Netherlands)

    Jungerius, P.D.; Riksen, M.J.P.M.

    2010-01-01

    The paper explores the possibilities of applying the analysis of laser altimetry images to Dutch drift sands. All along the European Sand Belt, which stretches from Great Britain to the Ural Mountains, Late Glacial cover sands, river dunes and other ice-age deposits were reactivated as drift sand du

  10. Contribution of laser altimetry images to the geomorphology of the Late Holocene inland drift sands of the European Sand Belt

    NARCIS (Netherlands)

    Jungerius, P.D.; Riksen, M.J.P.M.

    2010-01-01

    The paper explores the possibilities of applying the analysis of laser altimetry images to Dutch drift sands. All along the European Sand Belt, which stretches from Great Britain to the Ural Mountains, Late Glacial cover sands, river dunes and other ice–age deposits were reactivated as drift sand du

  11. Review of the Bat Flies of Honduras, Central America (Diptera: Streblidae

    Directory of Open Access Journals (Sweden)

    Carl W. Dick

    2013-01-01

    Full Text Available Streblid bat flies are obligate and host-specific blood-feeding ectoparasites of bats. While the bat flies of some American countries are well studied (e.g., Panama, Venezuela, little is known about Honduran Streblidae. Accumulation of substantial numbers of specimens, from several different collections, has enabled a relatively thorough treatment of the fauna. This study is based on 2,236 specimens representing 17 genera and 43 species of Streblidae. Of those presently reported, 11 genera and 32 species are new records for Honduras, increasing the number of known genera and species by 65% and 74%, respectively. Collection and host data are listed for all known Honduran streblid bat fly species. Comments regarding host associations and specificity, geographic distribution, and taxonomic problems are given in the species accounts.

  12. Revised irradiation doses to control melon fly, Mediterranean fruit fly, and oriental fruit fly (Diptera: Tephritidae) and a generic dose for tephritid fruit flies.

    Science.gov (United States)

    Follett, Peter A; Armstrong, John W

    2004-08-01

    Currently approved irradiation quarantine treatment doses for Bactrocera cucurbitae (Coquillet), melon fly; Ceratitis capitata (Wiedemann), Mediterranean fruit fly; and Bactrocera dorsalis (Hendel), oriental fruit fly, infesting fruits and vegetables for export from Hawaii to the continental United States are 210, 225, and 250 Gy, respectively. Irradiation studies were initiated to determine whether these doses could be reduced to lower treatment costs, minimize any adverse effects on quality, and support a proposed generic irradiation dose of 150 Gy for fruit flies. Dose-response tests were conducted with late third instars of wild and laboratory strains of the three fruit fly species, both in diet and in fruit. After x-ray irradiation treatment, data were taken on adult emergence, and adult female fecundity and fertility. Melon fly was the most tolerant of the three species to irradiation, and oriental fruit fly was more tolerant than Mediterranean fruit fly. Laboratory and wild strains of each species were equally tolerant of irradiation, and larvae were more tolerant when irradiated in fruit compared with artificial diet. An irradiation dose of 150 Gy applied to 93,666 melon fly late third instars in papayas resulted in no survival to the adult stage, indicating that this dose is sufficient to provide quarantine security. Irradiation doses of 100 and 125 Gy applied to 31,920 Mediterranean fruit fly and 55,743 oriental fruit fly late third instars, respectively, also resulted in no survival to the adult stage. Results support a proposed generic irradiation quarantine treatment dose of 150 Gy for all tephritid fruit flies.

  13. Oil shale, tar sand, coal research advanced exploratory process technology, jointly sponsored research

    Energy Technology Data Exchange (ETDEWEB)

    Speight, J.G.

    1992-01-01

    Accomplishments for the past quarter are presented for the following five tasks: oil shale; tar sand; coal; advanced exploratory process technology; and jointly sponsored research. Oil shale research covers oil shale process studies. Tar sand research is on process development of Recycle Oil Pyrolysis and Extraction (ROPE) Process. Coal research covers: coal combustion; integrated coal processing concepts; and solid waste management. Advanced exploratory process technology includes: advanced process concepts;advanced mitigation concepts; and oil and gas technology. Jointly sponsored research includes: organic and inorganic hazardous waste stabilization; CROW field demonstration with Bell Lumber and Pole; development and validation of a standard test method for sequential batch extraction fluid; PGI demonstration project; operation and evaluation of the CO[sub 2] HUFF-N-PUFF Process; fly ash binder for unsurfaced road aggregates; solid state NMR analysis of Mesaverde Group, Greater Green River Basin, tight gas sands; flow-loop testing of double-wall pipe for thermal applications; characterization of petroleum residue; shallow oil production using horizontal wells with enhanced oil recovery techniques; surface process study for oil recovery using a thermal extraction process; NMR analysis of samples from the ocean drilling program; in situ treatment of manufactured gas plant contaminated soils demonstration program; and solid state NMR analysis of naturally and artificially matured kerogens.

  14. Cemented backfilling technology with unclassified tailings based on vertical sand silo

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    A new technology characterized by rapidly non-mechanical settlement of unclassified tailings was developed based on a large number of tests,and dynamic settlement and continual slurry preparation without hardening in vertical sand silo were eventually realized by the addition of an effective flocculating agent (NPA).The results show that the sedimentation velocity of interface between unclassified tailings and water after the addition of NPA increases by 10-20 times,the sedimentation mass fraction of unclassified tailings at the bottom of vertical sand silo is up to 64%,the solid particle content of waste water meets the national standard,and the side influences of NPA can be removed by the addition of fly ash.The industrial test result shows that the system,the addition manner and the equipments are rational,and the vertical sand silo is used efficiently.This developed system is simple with large throughput,and the processing cost is 2.2 yuan(RMB)/m3,only 10%-20% of that by mechanical settlement.

  15. Flying qualities criteria and flight control design

    Science.gov (United States)

    Berry, D. T.

    1981-01-01

    Despite the application of sophisticated design methodology, newly introduced aircraft continue to suffer from basic flying qualities deficiencies. Two recent meetings, the DOD/NASA Workshop on Highly Augmented Aircraft Criteria and the NASA Dryden Flight Research Center/Air Force Flight Test Center/AIAA Pilot Induced Oscillation Workshop, addressed this problem. An overview of these meetings is provided from the point of view of the relationship between flying qualities criteria and flight control system design. Among the items discussed are flying qualities criteria development, the role of simulation, and communication between flying qualities specialists and control system designers.

  16. Research on the mechanical properties of desert sand high strength concrete%沙漠砂高强混凝土力学性能研究

    Institute of Scientific and Technical Information of China (English)

    杨维武; 陈云龙; 刘海峰; 马菊荣; 韩莉; 宋建夏

    2014-01-01

    The orthogonal experiment is carried out to analyze the influence of water-binder ratio,fly ash content,sand ratio and desert sand replacement ratio on the 7,28 d compressive strength and 28 d splitting tensile strength of desert sand high strength concrete.The opti-mum mix ratio of desert sand high strength concrete is also given out.On the basis of the optimal mixture ratio from orthogonal experi-ment,single factor experiment is carried out to study the influence of concrete compressive strength under different desert sand replace-ment ratio.Experimental result showed that it was practical to use the desert sand from Mu Us desert to mix desert sand high strength con-crete.The optimum desert sand replacement ratio of desert sand high strength concrete was from 0 to 40%.%通过正交试验,分析了沙漠砂替代率、粉煤灰掺量、砂率和水胶比对沙漠砂高强混凝土7、28 d抗压强度和28 d劈裂抗拉强度的影响;在正交试验基础上,通过单因素试验,进一步研究不同沙漠砂替代率对沙漠砂高强混凝土抗压强度的影响规律。研究结果表明:用沙漠砂替代中砂配制高强混凝土是可行的;综合考虑正交试验和单因素试验的研究成果,沙漠砂高强混凝土中沙漠砂的最佳替代率0~40%。

  17. Pretreatment of turkey fat-containing wastewater in coarse sand and gravel/coarse sand bioreactors.

    Science.gov (United States)

    Gaur, Rashmi Singh; Cai, Ling; Tuovinen, Olli H; Mancl, Karen M

    2010-02-01

    Fat, oil and grease in wastewater can be difficult to treat because of their slow decomposition. Traditional pretreatment facilities to remove fat, oil and grease from wastewater are increasingly costly. The hypothesis in this study was that pretreatment of animal fat-containing wastewater in sand and sand/gravel filters facilitates the conversion of slowly degradable organic matter measured as the difference between chemical oxygen demand (COD) and 5-day biochemical oxygen demand (BOD(5)) for subsequent biological treatment. The pretreatment was evaluated using simulated turkey-processing wastewater and coarse sand and sand/gravel filters at a constant hydraulic loading rate of 132L/m(2)/day. Two types of fixed media reactors were employed: (i) one set with a varying depth of coarse sand, and (ii) the second was similar but with an additional pea gravel cap. The results indicated that the relative removal of COD was slightly improved in the sand bioreactors with a pea gravel cap irrespective of the depth of coarse sand, but partial conversion to BOD(5) was not consistently demonstrated. Pea gravel may act as a sieve to entrap organic matter including fat globules from the wastewater. Multiple dosing at the same daily loading rate slightly improved the treatment efficiency of the sand bioreactors. The ratios of influent-COD/effluent-COD were always greater than 1.0 following a change in the dosing frequency after a rest period, suggesting that organic matter, specifically fat globules in this case, was retained by the column matrix.

  18. Probability of rebound and eject of sand particles in wind-blown sand movement

    Institute of Scientific and Technical Information of China (English)

    Li Xie; Xiaojing Zheng

    2007-01-01

    When incident particles impact into a sand bed in wind-blown sand movement, rebound of the incident particles and eject of the sand particles by the incident particles affect directly the development of wind sand flux. In order to obtain rebound and eject lift-off probability of the sand particles, we apply the particle-bed stochastic collision model presented in our pervious works to derive analytic solutions of velocities of the incident and impacted particles in the postcollision bed. In order to describe randomness inherent in the real particle-bed collision, we take the incident angle, theimpact position and the direction of resultant action of sand particles in sand bed on the impacted sand particle as random variables, and calculate the rebound and eject velocities,angles and coefficients (ratio of rebound and eject velocity to incident velocity). Numerical results are found in accordance with current experimental results. The rebound and eject lift-off probabilities versus the incident and creeping velocities are predicted.

  19. MORPHOMETRIC CHARACTERIZATION OF THE SAND FRACTION IN A SAND GRAIN IMAGE CAPTURE SYSTEM1

    Directory of Open Access Journals (Sweden)

    Lucimar Arruda Viana

    Full Text Available ABSTRACT Morphology studies assume significant importance in analysis of phenomena of granular systems packaging, in particular with a view to the use of the technique of soil stabilization named particle size correction in forest roads. In this context, this study aimed to develop and operationalize a Sand Grain Image Capture System and, hereby, determine the morphological indices of the sand fractions of two sandy soils called João Pinheiro (JP and Cachoeira da Prata (CP. Soil samples, air-dried, were sieved (2.0 mm nominal mesh size for removal of gravels. The materials that passed through the sieve were subjected to dispersion, washing in 0.053 mm nominal mesh size sieve, removal of organic matter and iron oxides to obtain the clean sand fractions. Subsequently, each soil sample was sieved for separation into twelve classes, between the diameters of 0.149 mm and 1.190 mm, using a Rotap shaker. Next, tests were carried out to characterize the morphometric attributes of the twelve classes of sand fractions of the soils studied. For validation of the performance of the Sand Grain Image Capture System, the results were compared to those obtained using a standard procedure for image analysis. The analysis of the results led to the following conclusions: (i the sand fraction of the JP soil presented higher values for the morphometric indices roundness, elongation and compactness compared to sand fraction of the CP soil; and (ii the Sand Grain Image Capture System worked properly, with practicality.

  20. Bright sand/dark dust: The identification of active sand surfaces on the Earth and Mars

    Science.gov (United States)

    Blount, H. G., II; Greeley, R.; Christensen, P. R.; Arvidson, R.

    1987-05-01

    Field studies and analysis of LANDSAT Thematic Mapper data in the Gran Desierto, Mexico may shed light on a technique to distinguish active from inactive (relict) sand surfaces. Active sand bodies in the study area are consistently brighter (by an average of 20%) at visual and near infrared wavelengths and darker at thermal infrared wavelengths than compositionally similar inactive sands. The reasons for the albedo difference between active and inactive sands are reviewed and the mixing model of Johnson et al. is examined for tracing the provenance of sands based on albedo and spectral variations. Portions of the wavelengths covered by the Mars Orbiter correspond to the Thematic Mapper data. The identification of active sands on Earth, with a priori knowledge of bulk composition and grain size distribution, may allow the remote mapping of active sand surfaces on Mars. In conjuction with thermal infrared remote sensing for composition, it may also provide a method for the remote determination of grain size distributions within sand/silt mixtures.