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Sample records for killing disease-transmitting mosquitoes

  1. Attracting, trapping and killing disease-transmitting mosquitoes using odor-baited stations - The Ifakara Odor-Baited Stations

    Directory of Open Access Journals (Sweden)

    John Alex N

    2010-03-01

    Full Text Available Abstract Background To accelerate efforts towards control and possibly elimination of mosquito-borne diseases such as malaria and lymphatic filariasis, optimally located outdoor interventions could be used to complement existing intradomicilliary vector control methods such as house spraying with insecticides and insecticidal bednets. Methods We describe a new odor-baited station for trapping, contaminating and killing disease-transmitting mosquitoes. This device, named the 'Ifakara Odor-baited Station' (Ifakara OBS, is a 4 m3 hut-shaped canvas box with seven openings, two of which may be fitted with interception traps to catch exiting mosquitoes. It is baited with synthetic human odors and may be augmented with contaminants including toxic insecticides or biological agents. Results In field trials where panels of fabric were soaked in 1% pirimiphos-methyl solution and suspended inside the Ifakara OBS, at least 73.6% of Anopheles arabiensis, 78.7% of Culex and 60% of Mansonia mosquitoes sampled while exiting the OBS, died within 24 hours. When used simply as a trap and evaluated against two existing outdoor traps, Ifakara Tent trap and Mosquito Magnet-X®, the OBS proved more efficacious than the Ifakara Tent trap in catching all mosquito species found (P ®, it was equally efficacious in catching An. arabiensis (P = 0.969, but was less efficacious against Culex (P Mansonia species (P Conclusion The Ifakara OBS is efficacious against disease-carrying mosquitoes including the malaria vector, An. arabiensis and Culicine vectors of filarial worms and arboviruses. It can be used simultaneously as a trap and as a contamination or killing station, meaning most mosquitoes which escape trapping would leave when already contaminated and die shortly afterwards. This technique has potential to complement current vector control methods, by targeting mosquitoes in places other than human dwellings, but its effectiveness in the field will require cheap, long-lasting and easy-to-use mosquito lures.

  2. Common host-derived chemicals increase catches of disease-transmitting mosquitoes and can improve early warning systems for rift valley fever virus

    Science.gov (United States)

    Rift Valley fever (RVF), a mosquito-borne zoonosis, is a major public health problem in sub-Saharan Africa. The emergence and re-emergence of the disease in the last 20 years especially in East Africa, poses a looming health threat which is likely to spread to beyond Africa. This threat is exacerbat...

  3. Surplus Killing by Predatory Larvae of Corethrella appendiculata: Prepupal Timing and Site-Specific Attack on Mosquito Prey

    OpenAIRE

    Lounibos, L. P.; Makhni, S.; Alto, B. W.; Kesavaraju, B.

    2008-01-01

    Surplus or ‘wasteful’ killing of uneaten prey has been documented in the fourth larval instar of various species of the mosquito genus Toxorhynchites that occur in treeholes and other phytotelmata. Here we document surplus killing by the predatory midge Corethrella appendiculata, which in Florida cohabits treeholes and artificial containers with larvae of Toxorhynchites rutilus. Provided with a surfeit of larval mosquito prey, surplus killing was observed only in the fourth instar of C. a...

  4. Mass production of Coelomomyes, a fungus that kills mosquitoes.

    Science.gov (United States)

    Couch, J N

    1972-08-01

    In work on the control of mosquitoes by the fungus Coelomomyces, the main problem is a source of inoculum since the fungus has not been cultured artificially with production of sporangia. We reared the larvae of Anopheles quadrimaculatus in algal water instead of in water with soil. By addition of inoculum once or twice in small amounts, the larvae become infected, and many grow to large fourth instars whose bodies are filled with sporangia. Such larvae are perfect for inoculum. If inoculum is added in much larger amounts and so timed that sporangia will be discharging spores during the first, second, and third ecdyses up to 100%, infection occurs, most of the larvae dying as late second or early third instars. This type of infection is good for extermination of mosquitoes but not for production of inoculum. Crude field tests have averaged 60% infection. PMID:4506071

  5. Mass Production of Coelomomyces, a Fungus That Kills Mosquitoes

    Science.gov (United States)

    Couch, J. N.

    1972-01-01

    In work on the control of mosquitoes by the fungus Coelomomyces, the main problem is a source of inoculum since the fungus has not been cultured artificially with production of sporangia. We reared the larvae of Anopheles quadrimaculatus in algal water instead of in water with soil. By addition of inoculum once or twice in small amounts, the larvae become infected, and many grow to large fourth instars whose bodies are filled with sporangia. Such larvae are perfect for inoculum. If inoculum is added in much larger amounts and so timed that sporangia will be discharging spores during the first, second, and third ecdyses up to 100%, infection occurs, most of the larvae dying as late second or early third instars. This type of infection is good for extermination of mosquitoes but not for production of inoculum. Crude field tests have averaged 60% infection. Images PMID:4506071

  6. MAN, MOSQUITOES AND MICROBES.

    Science.gov (United States)

    SCHOONOVER, ROBERT A.

    THE CONTROL OF MOSQUITOES IS A MATTER OF INCREASING CONCERN IN THE STATE OF FLORIDA. A BRIEF DESCRIPTION OF THE LIFE CYCLE, VARIOUS SPECIES, CONTROL, AND DESCRIPTION OF DISEASES TRANSMITTED BY THE MOSQUITO WAS PRESENTED. THE ARTICLE CONCLUDED THAT MOSQUITO CONTROL IS NOT ONLY A HEALTH PROBLEM, BUT ALSO A MATTER OF IMPROVED ECONOMICS IN RELATION TO…

  7. [Diseases transmitted by ticks locally and abroad].

    Science.gov (United States)

    Gétaz, L; Loutan, L; Mezger, N

    2012-05-01

    This article provides a brief overview of some diseases transmitted by ticks. These vectors do not transmit only Lyme disease and tickborne-encephalitis, even in Switzerland. Several tick-borne diseases cause nonspecific flu-like symptoms. Nevertheless sometimes severe, some of these diseases can be treated with specific treatments. Repellents, appropriate clothes impregnated with permethrine and prompt removal of the tick are effective preventive measures to limit the risk of infection. There is an effective vaccine which protects against tick-borne encephalitis. PMID:22662624

  8. Mosquitoes

    Science.gov (United States)

    0000-00-00

    This tutorial is part of a series of entomological tutorials and covers the general biology and ecology of mosquitoes. The tutorial has 100 questions (50 in each of 2 tutorials); incorrect answers lead to additional information describing the correct answers. Covers all mosquito genera and their habitats, identification, life cycle, biology, and economic importance. Requires Windows. MAC is not supported. The cost for the tutorial CD is $15.

  9. What does not kill them makes them stronger: larval environment and infectious dose alter mosquito potential to transmit filarial worms.

    Science.gov (United States)

    Breaux, Jennifer A; Schumacher, Molly K; Juliano, Steven A

    2014-07-01

    For organisms with complex life cycles, larval environments can modify adult phenotypes. For mosquitoes and other vectors, when physiological impacts of stressors acting on larvae carry over into the adult stage they may interact with infectious dose of a vector-borne pathogen, producing a range of phenotypes for vector potential. Investigation of impacts of a common source of stress, larval crowding and intraspecific competition, on adult vector interactions with pathogens may increase our understanding of the dynamics of pathogen transmission by mosquito vectors. Using Aedes aegypti and the nematode parasite Brugia pahangi, we demonstrate dose dependency of fitness effects of B. pahangi infection on the mosquito, as well as interactions between competitive stress among larvae and infectious dose for resulting adults that affect the physiological and functional ability of mosquitoes to act as vectors. Contrary to results from studies on mosquito-arbovirus interactions, our results suggest that adults from crowded larvae may limit infection better than do adults from uncrowded controls, and that mosquitoes from high-quality larval environments are more physiologically and functionally capable vectors of B. pahangi. Our results provide another example of how the larval environment can have profound effects on vector potential of resulting adults. PMID:24827444

  10. The Effect of Virus-Blocking Wolbachia on Male Competitiveness of the Dengue Vector Mosquito, Aedes aegypti

    OpenAIRE

    Segoli, Michal; Hoffmann, Ary A.; Lloyd, Jane; Omodei, Gavin J.; Ritchie, Scott A

    2014-01-01

    Dengue is a tropical, potentially lethal disease transmitted by mosquitoes. A new control method involves the release of mosquitoes infected by the bacterium Wolbachia that blocks the transmission of the dengue virus to humans. However, possible negative effects of Wolbachia on mosquito reproductive success could substantially slow the spread of this bacterium in mosquito populations, reducing the feasibility of this method. We found that male mosquitoes infected by Wolbachia are equally succ...

  11. Mosquito Control

    Science.gov (United States)

    ... Share Facebook Twitter Google+ Pinterest Contact Us Mosquito Control About Mosquitoes General Information Life Cycle Information on ... is Right for You DEET Pesticides for Mosquito Control Larvicides Adulticides Misting Systems Getting Help with Mosquito ...

  12. The Plasmodium bottleneck: malaria parasite losses in the mosquito vector

    OpenAIRE

    Smith, Ryan C.; Vega-rodri?guez, Joel; Jacobs-lorena, Marcelo

    2014-01-01

    Nearly one million people are killed every year by the malaria parasite Plasmodium. Although the disease-causing forms of the parasite exist only in the human blood, mosquitoes of the genus Anopheles are the obligate vector for transmission. Here, we review the parasite life cycle in the vector and highlight the human and mosquito contributions that limit malaria parasite development in the mosquito host. We address parasite killing in its mosquito host and bottlenecks in pa...

  13. Wash resistance and repellent properties of Africa University mosquito blankets against mosquitoes

    Directory of Open Access Journals (Sweden)

    M. Zimba

    2013-04-01

    Full Text Available The effect of permethrin-treated Africa University (AU mosquito blankets on susceptible female Anopheles gambiae sensu lato mosquitoes was studied under laboratory conditions at Africa University Campus in Mutare, Zimbabwe. Wash resistance (ability to retain an effective dose that kills ?80% of mosquitoes after a number of washes and repellence (ability to prevent ?80% of mosquito bites properties were studied. The AU blankets were wash resistant when 100% mortality was recorded up to 20 washes, declining to 90% after 25 washes. Untreated AU blankets did not cause any mortality on mosquitoes. However, mosquito repellence was 96%, 94%, 97.9%, 87%, 85% and 80.7% for treated AU blankets washed 0, 5, 10, 15, 20 and 25 times, respectively. Mosquito repellence was consistently above 80% from 0-25 washes. In conclusion, AU blankets washed 25 times were effective in repelling and killing An. gambiae sl mosquitoes under laboratory conditions.

  14. Wash resistance and repellent properties of Africa University mosquito blankets against mosquitoes

    OpenAIRE

    Zimba, M.; Mutambu, S. L.; Chiwade, T.; Makuwaza, A.; Lukwa, N.; Munosiyei, P.

    2013-01-01

    The effect of permethrin-treated Africa University (AU) mosquito blankets on susceptible female Anopheles gambiae sensu lato mosquitoes was studied under laboratory conditions at Africa University Campus in Mutare, Zimbabwe. Wash resistance (ability to retain an effective dose that kills ?80% of mosquitoes after a number of washes) and repellence (ability to prevent ?80% of mosquito bites) properties were studied. The AU blankets were wash resistant when 100% mortality was recorded up t...

  15. HERBAL CONTROL OF MOSQUITO LARVAE

    OpenAIRE

    Chaudhari Priyanka S, Chaudhari Sv Jangam Sampada

    2013-01-01

    Mosquitoes are the vectors for the dreadful diseases of mankind. For control of larval stages of mosquito, herbal plant extracts/ botanical insecticides are being tried. In the present study aqueous extract of some traditional medicinal herbal plants i.e. Neem (Azadirechta indica), Tobacco (Nicotiana tabacum), Turmeric (Curcuma longa), Tulasi (Ocimum santum), and Ginger (Zingiber officinale) were tested for their Larvicidal activity. The successful attempt is made to kill the larvae, the prem...

  16. Entomopathogenic fungi for mosquito control: A review

    OpenAIRE

    Ernst-Jan Scholte; Knols, Bart G. J.; Samson, Robert A.; Willem Takken

    2004-01-01

    Fungal diseases in insects are common and widespread and can decimate their populations in spectacular epizootics. Virtually all insect orders are susceptible to fungal diseases, including Dipterans. Fungal pathogens such as Lagenidium, Coelomomyces and Culicinomyces are known to affect mosquito populations, and have been studied extensively. There are, however, many other fungi that infect and kill mosquitoes at the larval and/or adult stage. The discovery, in 1977, of the selective mosquito...

  17. Malaria Mosquitoes Attracted by Fatal Fungus

    OpenAIRE

    George, Justin; Jenkins, Nina E.; Blanford, Simon; Thomas, Matthew B.; Baker, Thomas C.

    2013-01-01

    Insect-killing fungi such as Beauveria bassiana are being evaluated as possible active ingredients for use in novel biopesticides against mosquito vectors that transmit malaria. Fungal pathogens infect through contact and so applications of spores to surfaces such as walls, nets, or other resting sites provide possible routes to infect mosquitoes in and around domestic dwellings. However, some insects can detect and actively avoid fungal spores to reduce infection risk. If true for mosquitoes...

  18. Sheep skin odor improves trap captures of mosquito vectors of Rift Valley fever

    OpenAIRE

    Tchouassi, David P.; Sang, Rosemary; Sole, Catherine L.; Bastos, Armanda D. S.; Mithoefer, Klaus; Torto, Baldwyn

    2012-01-01

    In recent years, the East African region has seen an increase in arboviral diseases transmitted by blood-feeding arthropods. Effective surveillance to monitor and reduce incidence of these infections requires the use of appropriate vector sampling tools. Here, trapped skin volatiles on fur from sheep, a known preferred host of mosquito vectors of Rift Valley fever virus (RVFV), were used with a standard CDC light trap to improve catches of mosquito vectors. We tested the standard CDC light tr...

  19. Oral toxicity of Bacillus thuringiensis subsp. israelensis to adult mosquitoes.

    OpenAIRE

    Klowden, M J; Bulla, L. A.

    1984-01-01

    The solubilized entomotoxin of Bacillus thuringiensis subsp. israelensis killed adult male and female mosquitoes of several genera and of various physiological states when it was administered orally. Adult mosquito mortality was further influenced when the preparation was contained in sucrose solution. The potential implication for the control of adult mosquitoes is discussed.

  20. Mosquito Modifications: New Approaches to Controlling Malaria

    Science.gov (United States)

    Sharon Levy (; )

    2007-11-01

    This article from the November 2007 issue of BioScience examines the historical and current methods to control Malaria.Malaria kills about one million people each year, but efforts to destroy disease-carrying mosquitoes have succeeded only in breeding tougher bugs. Researchers have begun to look for ways to create malaria-resistant mosquitoes. One approach is to bioengineer transgenic mosquitoes that, when released into the wild, would lead to a new race of malaria-proof young. Another approach uses mosquitoes' natural resistance to Plasmodium infection.

  1. Entomopathogenic fungi for mosquito control: a review.

    Science.gov (United States)

    Scholte, Ernst-Jan; Knols, Bart G J; Samson, Robert A; Takken, Willem

    2004-01-01

    Fungal diseases in insects are common and widespread and can decimate their populations in spectacular epizootics. Virtually all insect orders are susceptible to fungal diseases, including Dipterans. Fungal pathogens such as Lagenidium, Coelomomyces and Culicinomyces are known to affect mosquito populations, and have been studied extensively. There are, however, many other fungi that infect and kill mosquitoes at the larval and/or adult stage. The discovery, in 1977, of the selective mosquito-pathogenic bacterium Bacillus thuringiensis Berliner israelensis (Bti) curtailed widespread interest in the search for other suitable biological control agents. In recent years interest in mosquito-killing fungi is reviving, mainly due to continuous and increasing levels of insecticide resistance and increasing global risk of mosquito-borne diseases. This review presents an update of published data on mosquito-pathogenic fungi and mosquito-pathogen interactions, covering 13 different fungal genera. Notwithstanding the potential of many fungi as mosquito control agents, only a handful have been commercialized and are marketed for use in abatement programs. We argue that entomopathogenic fungi, both new and existing ones with renewed/improved efficacies may contribute to an expansion of the limited arsenal of effective mosquito control tools, and that they may contribute in a significant and sustainable manner to the control of vector-borne diseases such as malaria, dengue and filariasis. PMID:15861235

  2. Entomopathogenic fungi for mosquito control: A review

    Directory of Open Access Journals (Sweden)

    Ernst-Jan Scholte

    2004-06-01

    Full Text Available Fungal diseases in insects are common and widespread and can decimate their populations in spectacular epizootics. Virtually all insect orders are susceptible to fungal diseases, including Dipterans. Fungal pathogens such as Lagenidium, Coelomomyces and Culicinomyces are known to affect mosquito populations, and have been studied extensively. There are, however, many other fungi that infect and kill mosquitoes at the larval and/or adult stage. The discovery, in 1977, of the selective mosquito-pathogenic bacterium Bacillus thuringiensis Berliner israelensis (Bti curtailed widespread interest in the search for other suitable biological control agents. In recent years interest in mosquito-killing fungi is reviving, mainly due to continuous and increasing levels of insecticide resistance and increasing global risk of mosquito-borne diseases. This review presents an update of published data on mosquito-pathogenic fungi and mosquito-pathogen interactions, covering 13 different fungal genera. Notwithstanding the potential of many fungi as mosquito control agents, only a handful have been commercialized and are marketed for use in abatement programs. We argue that entomopathogenic fungi, both new and existing ones with renewed/improved efficacies may contribute to an expansion of the limited arsenal of effective mosquito control tools, and that they may contribute in a significant and sustainable manner to the control of vector-borne diseases such as malaria, dengue and filariasis.

  3. The Plasmodium bottleneck: malaria parasite losses in the mosquito vector

    Scientific Electronic Library Online (English)

    Ryan C, Smith; Joel, Vega-Rodríguez; Marcelo, Jacobs-Lorena.

    2014-08-01

    Full Text Available Nearly one million people are killed every year by the malaria parasite Plasmodium. Although the disease-causing forms of the parasite exist only in the human blood, mosquitoes of the genus Anopheles are the obligate vector for transmission. Here, we review the parasite life cycle in the vector and [...] highlight the human and mosquito contributions that limit malaria parasite development in the mosquito host. We address parasite killing in its mosquito host and bottlenecks in parasite numbers that might guide intervention strategies to prevent transmission.

  4. The Plasmodium bottleneck: malaria parasite losses in the mosquito vector.

    Science.gov (United States)

    Smith, Ryan C; Vega-Rodríguez, Joel; Jacobs-Lorena, Marcelo

    2014-08-01

    Nearly one million people are killed every year by the malaria parasite Plasmodium. Although the disease-causing forms of the parasite exist only in the human blood, mosquitoes of the genus Anopheles are the obligate vector for transmission. Here, we review the parasite life cycle in the vector and highlight the human and mosquito contributions that limit malaria parasite development in the mosquito host. We address parasite killing in its mosquito host and bottlenecks in parasite numbers that might guide intervention strategies to prevent transmission. PMID:25185005

  5. HERBAL CONTROL OF MOSQUITO LARVAE

    Directory of Open Access Journals (Sweden)

    Chaudhari Priyanka S, Chaudhari SV* Jangam Sampada, Shinde JS, Wankhede Sneha

    2013-04-01

    Full Text Available Mosquitoes are the vectors for the dreadful diseases of mankind. For control of larval stages of mosquito, herbal plant extracts/ botanical insecticides are being tried. In the present study aqueous extract of some traditional medicinal herbal plants i.e. Neem (Azadirechta indica, Tobacco (Nicotiana tabacum, Turmeric (Curcuma longa, Tulasi (Ocimum santum, and Ginger (Zingiber officinale were tested for their Larvicidal activity. The successful attempt is made to kill the larvae, the premature stage of mosquitoes by using safe and socio-economical herbal plant extract mixtures. Ginger+Tobacco, Neem+Tobbaco and Ginger Neem, Turmeric, Tobacco and Tulasi showed highest larvicidal activity. The results obtained show that this plant material exhibited larvicidal activity and could be considered as potent natural larvicidal agent without any toxic effects.

  6. Toxicity of Bacillus sphaericus crystal toxin to adult mosquitoes.

    OpenAIRE

    Stray, J E; Klowden, M J; Hurlbert, R. E.

    1988-01-01

    Adult Culex quinquefasciatus mosquitoes were killed by alkaline-solubilized Bacillus sphaericus toxin when it was introduced by enema into the midgut of the insect but not when it was administered orally. Adult Aedes aegypti mosquitoes were not affected by the toxin.

  7. Evaluation of selected South African ethnomedicinal plants as mosquito repellents against the Anopheles arabiensis mosquito in a rodent model

    OpenAIRE

    Folb Peter I; Bhagwandin Niresh; Newmarch Marion; Crouch Neil R; Maharaj Vinesh; Maharaj Rajendra; Pillay Pamisha; Gayaram Reshma

    2010-01-01

    Abstract Background This study was initiated to establish whether any South African ethnomedicinal plants (indigenous or exotic), that have been reported to be used traditionally to repel or kill mosquitoes, exhibit effective mosquito repellent properties. Methods Extracts of a selection of South African taxa were tested for repellency properties in an applicable mosquito feeding-probing assay using unfed female Anopheles arabiensis. Results Although a water extract of the roots of Chenopodiu...

  8. Natural Plant Sugar Sources of Anopheles Mosquitoes Strongly Impact Malaria Transmission Potential

    OpenAIRE

    GU, WEIDONG; Müller, Günter; Schlein, Yosef; Novak, Robert J; Beier, John C.

    2011-01-01

    An improved knowledge of mosquito life history could strengthen malaria vector control efforts that primarily focus on killing mosquitoes indoors using insecticide treated nets and indoor residual spraying. Natural sugar sources, usually floral nectars of plants, are a primary energy resource for adult mosquitoes but their role in regulating the dynamics of mosquito populations is unclear. To determine how the sugar availability impacts Anopheles sergentii populations, mark-release-recapture ...

  9. PERCEPTIONS REGARDING MOSQUITO BORNE DISEASES IN AN URBAN AREA OF RAJKOT CITY

    Directory of Open Access Journals (Sweden)

    Amul B. Patel

    2011-04-01

    Full Text Available Background: Mosquito borne diseases is a growing urban problem because of unplanned urbanization, industrialization and excessive population growth coupled with rural to urban migration. For developing a suitable and effective health education strategy, it is inevitable to understand the level of knowledge of the community, their attitude and practices regarding mosquito borne diseases. Materials and Methods: The present study was carried out in an urban field practice area of Urban Health Centre in Rajkot city. Total 500 houses were selected for study by systematic random sampling. Data was collected using a semi-structured questionnaire during transmission season of vector borne diseases. The results were analyzed using the SPSS 17 software. Results: 90% respondents agreed that mosquitoes are a problem. 30.4% didn?t know breeding sites of mosquitoes. Only 11.6% of people associated clean water collections with mosquito breeding. Regarding diseases transmitted by mosquito, 62% answered malaria, 37.4% were not aware and 8.8% people mentioned about Filariasis, Dengue or Japanese encephalitis. 4.7% granted mosquito control as responsibility of community. 61.4 % were using repellents for prevention against mosquito bites and 39% not taking any preventive measure. 67.8% consulted private practitioner for treatment. Conclusion: Intensified efforts towards creating public awareness and mobilizing the community regarding the preventive measures they can take are needed. [National J of Med Res 2011; 1(2.000: 45-47

  10. Mosquito, egg raft (image)

    Science.gov (United States)

    Mosquitoes of the Culex species lay their eggs in the form of egg rafts that float in ... feed on micro-organisms before developing into flying mosquitoes. (Image courtesy of the Centers for Disease Control ...

  11. Transgenic mosquitoes for malaria control: progresses and challenges / Mosquitos transgênicos para o controle da malária: progressos e desafios

    Scientific Electronic Library Online (English)

    Luciano A., Moreira; Marcelo, Jacobs-Lorena.

    2003-12-01

    Full Text Available A malária mata milhões de pessoas a cada ano e as estratégias atuais de controle da doença, como inseticidas e drogas não têm sido tão eficientes. Por este motivo, novos meios para o combate à malária são de extrema importância. Avanços no estudo do mosquito vetor e sua interação com o parasito da m [...] alária fizeram os cientistas pensarem que é possível a manipulação genética dos mosquitos para torná-los vetores ineficientes. Neste artigo, revisamos os avanços na introdução de genes exógenos na linhagem germinativa de mosquitos, a caracterização de promotores específicos de certos tecidos, a identificação de produtos gênicos que bloqueiam o parasita no mosquito, bem como discutimos a recente geração de mosquitos transgênicos, menos eficientes na transmissão de malária. Enquanto muitos progressos foram obtidos, muitos anos de pesquisa são ainda necessários para que mosquitos transgênicos possam ser utilizados na natureza. Abstract in english Malaria kills millions of people every year and the current strategies to control the disease, such as insecticides and drugs have not been completely efficient. Because of that, novel means to fight against malaria are of utmost importance. Advances in the study of the mosquito vector and its inter [...] actions with the malaria parasite made scientists think that it is possible to genetically manipulate the mosquitoes to make them inefficient vectors. Here we review the advances on the introduction of foreign genes into the mosquito germ line, the characterization of tissue-specific promoters, the identification of gene products that block development of the parasite in the mosquito, and we discuss the recent generation of transgenic mosquitoes impaired for malaria transmission. While much progress has been made, many years of research are still needed before transgenic mosquitoes can be used in the field.

  12. Pesticides and Mosquito Control

    Science.gov (United States)

    This factsheet from the Environmental Protection Agency includes several summary documents on the problem of mosquito-borne diseases and the pesticides used to control mosquitoes. The resources cover issues from mosquito biology through the EPA's recent findings on the negative health impacts of Malathion.

  13. Target product profile choices for intra-domiciliary malaria vector control pesticide products: repel or kill?

    Directory of Open Access Journals (Sweden)

    Moore Sarah J

    2011-07-01

    Full Text Available Abstract Background The most common pesticide products for controlling malaria-transmitting mosquitoes combine two distinct modes of action: 1 conventional insecticidal activity which kills mosquitoes exposed to the pesticide and 2 deterrence of mosquitoes away from protected humans. While deterrence enhances personal or household protection of long-lasting insecticidal nets and indoor residual sprays, it may also attenuate or even reverse communal protection if it diverts mosquitoes to non-users rather than killing them outright. Methods A process-explicit model of malaria transmission is described which captures the sequential interaction between deterrent and toxic actions of vector control pesticides and accounts for the distinctive impacts of toxic activities which kill mosquitoes before or after they have fed upon the occupant of a covered house or sleeping space. Results Increasing deterrency increases personal protection but consistently reduces communal protection because deterrent sub-lethal exposure inevitably reduces the proportion subsequently exposed to higher lethal doses. If the high coverage targets of the World Health Organization are achieved, purely toxic products with no deterrence are predicted to generally provide superior protection to non-users and even users, especially where vectors feed exclusively on humans and a substantial amount of transmission occurs outdoors. Remarkably, this is even the case if that product confers no personal protection and only kills mosquitoes after they have fed. Conclusions Products with purely mosquito-toxic profiles may, therefore, be preferable for programmes with universal coverage targets, rather than those with equivalent toxicity but which also have higher deterrence. However, if purely mosquito-toxic products confer little personal protection because they do not deter mosquitoes and only kill them after they have fed, then they will require aggressive "catch up" campaigns, with behaviour change communication strategies that emphasize the communal nature of protection, to achieve high coverage rapidly.

  14. Metarhizium anisopliae Pathogenesis of Mosquito Larvae: A Verdict of Accidental Death

    OpenAIRE

    Butt, Tariq M.; Greenfield, Bethany P. J.; Greig, Carolyn; Maffeis, Thierry G. G.; Taylor, James W. D.; Piasecka, Justina; Dudley, Ed; Abdulla, Ahmed; Dubovskiy, Ivan M.; Garrido-jurado, Inmaculada; Quesada-moraga, Enrique; Penny, Mark W.; Eastwood, Daniel C.

    2013-01-01

    Metarhizium anisopliae, a fungal pathogen of terrestrial arthropods, kills the aquatic larvae of Aedes aegypti, the vector of dengue and yellow fever. The fungus kills without adhering to the host cuticle. Ingested conidia also fail to germinate and are expelled in fecal pellets. This study investigates the mechanism by which this fungus adapted to terrestrial hosts kills aquatic mosquito larvae. Genes associated with the M. anisopliae early pathogenic response (proteinases Pr1 and Pr2, and a...

  15. Activation of Akt Signaling Reduces the Prevalence and Intensity of Malaria Parasite Infection and Lifespan in Anopheles stephensi Mosquitoes

    OpenAIRE

    Corby-Harris, Vanessa; Drexler, Anna; Watkins de Jong, Laurel; Antonova, Yevgeniya; Pakpour, Nazzy; Ziegler, Rolf; Ramberg, Frank; Lewis, Edwin E.; Brown, Jessica M.; Luckhart, Shirley; Riehle, Michael A.

    2010-01-01

    Malaria (Plasmodium spp.) kills nearly one million people annually and this number will likely increase as drug and insecticide resistance reduces the effectiveness of current control strategies. The most important human malaria parasite, Plasmodium falciparum, undergoes a complex developmental cycle in the mosquito that takes approximately two weeks and begins with the invasion of the mosquito midgut. Here, we demonstrate that increased Akt signaling in the mosquito midgut disrupts parasite ...

  16. Killing Mosquitoes and Keeping Practice: Teacher Education as Sustaining Paradox

    Science.gov (United States)

    Keiser, David Lee

    2013-01-01

    The moral and ethical charge of teaching and teacher education includes sustaining equanimity and paradox, and maintaining poise amongst contradicting policies and interests. This paper draws upon the wisdom of the Tao Te Ching to address some paradoxes in education and teacher preparation. Specifically, the article looks at four chapters of the…

  17. Sensory and behavioural responses of the malaria mosquito Anopheles gambiae to human odours

    OpenAIRE

    Qiu, Y.T.

    2005-01-01

    Malaria is one of the most serious human diseases, affecting between 300 and 600 million people per year and killing, on average, two children per minute. In tropicalAfricathe mosquito Anopheles gambiae Giles sensu stricto is responsible for much of the transmission of malaria parasites between humans. This mosquito species preferably feeds on human blood, rests inside human houses and breeds close to human dwellings, making it an effective malaria vector. The major cues guiding Anopheles gam...

  18. Toxicity of Bacillus thuringiensis subsp. israelensis to adult Aedes aegypti mosquitoes.

    OpenAIRE

    Klowden, M J; Held, G. A.; Bulla, L. A.

    1983-01-01

    Adult female Aedes aegypti mosquitoes were killed by the parasporal crystals of Bacillus thuringiensis subsp. israelensis (ONR-60A) when the crystals were introduced into the insect midgut as an enema. The 50% lethal dose for intact parasporal crystals was 0.21 microgram/mg of mosquito (wet weight), and for solubilized crystals the 50% lethal dose was 0.04 microgram/mg. These values were compared with 50% lethal concentrations in a free-feeding larval mosquito bioassay of 0.018 and 1.28 micro...

  19. Evaluation of selected South African ethnomedicinal plants as mosquito repellents against the Anopheles arabiensis mosquito in a rodent model

    Directory of Open Access Journals (Sweden)

    Folb Peter I

    2010-10-01

    Full Text Available Abstract Background This study was initiated to establish whether any South African ethnomedicinal plants (indigenous or exotic, that have been reported to be used traditionally to repel or kill mosquitoes, exhibit effective mosquito repellent properties. Methods Extracts of a selection of South African taxa were tested for repellency properties in an applicable mosquito feeding-probing assay using unfed female Anopheles arabiensis. Results Although a water extract of the roots of Chenopodium opulifolium was found to be 97% as effective as DEET after 2 mins, time lag studies revealed a substantial reduction in efficacy (to 30% within two hours. Conclusions None of the plant extracts investigated exhibited residual repellencies >60% after three hours.

  20. Assessing the efficacy of candidate mosquito repellents against the background of an attractive source that mimics a human host.

    Science.gov (United States)

    Menger, D J; Van Loon, J J A; Takken, W

    2014-12-01

    Mosquito repellents are used around the globe to protect against nuisance biting and disease-transmitting mosquitoes. Recently, there has been renewed interest in the development of repellents as tools to control the transmission of mosquito-borne diseases. We present a new bioassay for the accurate assessment of candidate repellent compounds, using a synthetic odour that mimics the odour blend released by human skin. Using DEET (N,N-diethyl-meta-toluamide) and PMD (p-menthane-3,8-diol) as reference compounds, nine candidate repellents were tested, of which five showed significant repellency to the malaria mosquito Anopheles gambiae sensu stricto (Diptera: Culicidae). These included: 2-nonanone; 6-methyl-5-hepten-2-one; linalool; ?-decalactone, and ?-undecalactone. The lactones were also tested on the yellow fever mosquito Aedes aegypti (Stegomyia aegypti) (Diptera: Culicidae), against which they showed similar degrees of repellency. We conclude that the lactones are highly promising repellents, particularly because these compounds are pleasant-smelling, natural products that are also present in human food sources. PMID:24797537

  1. The entomopathogenic fungus Beauveria bassiana reduces instantaneous blood feeding in wild multi-insecticide-resistant Culex quinquefasciatus mosquitoes in Benin, West Africa

    OpenAIRE

    Howard Annabel FV; N'guessan Raphael; Koenraadt Constantianus JM; Asidi Alex; Farenhorst Marit; Akogbéto Martin; Thomas Matthew B; Knols Bart GJ; Takken Willem

    2010-01-01

    Abstract Background Mosquito-borne diseases are still a major health risk in many developing countries, and the emergence of multi-insecticide-resistant mosquitoes is threatening the future of vector control. Therefore, new tools that can manage resistant mosquitoes are required. Laboratory studies show that entomopathogenic fungi can kill insecticide-resistant malaria vectors but this needs to be verified in the field. Methods The present study investigated whether these fungi will be effect...

  2. Efficacy of Australian quarantine procedures against the mosquito Aedes aegypti.

    Science.gov (United States)

    Ritchie, S A

    2001-06-01

    Methods employed by Australian quarantine officers to control Aedes mosquitoes in containers were tested against all stages of Aedes aegypti. Saltwater emersion killed all larvae but not pupae or eggs that were briefly exposed. Swimming pool chlorine, methyl bromide fumigation, and permethrin (2% active ingredient) spray provided 100% mortality of eggs, larvae, and pupae. Aerosol sprays incorporating synthetic pyrethrins are practical and also provide effective control of adults. PMID:11480817

  3. Study of mosquito attractants for photo catalytic mosquito trap

    OpenAIRE

    Dewi Tristantini; Slamet -; Angela Jessica Stephanie

    2014-01-01

    Photo catalytic mosquito trap is made of TiO2-Activated Carbon (AC) with a certain composition of AC. Research concerns on the heat spectrum which is produced by combination process of existing CO2 and humid air. The purpose of performance testing is to observe capability of this device in trapping mosquitoes related to the air temperature profile for heat spectrum is play important role for attracting mosquitoes. Result shows photo catalytic mosquito trap is more effective than devices which...

  4. Prallethrin-induced excitation increases contact between sprayed ultra-low-volume droplets and flying mosquitoes (Diptera: Culicidae) in a wind tunnel

    Science.gov (United States)

    Mosquitoes are important in the United States due to their roles as pestiferous biters and vectors of diseases such as West Nile Virus and Dengue. Conventional applications of pesticides in spray clouds are often limited by their ability to contact and kill mosquitoes that may be resting or hiding ...

  5. Perspectives in the control of infectious diseases by transgenic mosquitoes in the post-genomic era: a review

    Directory of Open Access Journals (Sweden)

    Márcia Aparecida Sperança

    2007-06-01

    Full Text Available Arthropod-borne diseases caused by a variety of microorganisms such as dengue virus and malaria parasites afflict billions of people worldwide imposing major economic and social burdens. Despite many efforts, vaccines against diseases transmitted by mosquitoes, with the exception of yellow fever, are not available. Control of such infectious pathogens is mainly performed by vector management and treatment of affected individuals with drugs. However, the numbers of insecticide-resistant insects and drug-resistant parasites are increasing. Therefore, inspired in recent years by a lot of new data produced by genomics and post-genomics research, several scientific groups have been working on different strategies to control infectious arthropod-borne diseases. This review focuses on recent advances and perspectives towards construction of transgenic mosquitoes refractory to malaria parasites and dengue virus transmission.

  6. Perspectives in the control of infectious diseases by transgenic mosquitoes in the post-genomic era: a review

    Scientific Electronic Library Online (English)

    Márcia Aparecida, Sperança; Margareth Lara, Capurro.

    2007-06-01

    Full Text Available Arthropod-borne diseases caused by a variety of microorganisms such as dengue virus and malaria parasites afflict billions of people worldwide imposing major economic and social burdens. Despite many efforts, vaccines against diseases transmitted by mosquitoes, with the exception of yellow fever, ar [...] e not available. Control of such infectious pathogens is mainly performed by vector management and treatment of affected individuals with drugs. However, the numbers of insecticide-resistant insects and drug-resistant parasites are increasing. Therefore, inspired in recent years by a lot of new data produced by genomics and post-genomics research, several scientific groups have been working on different strategies to control infectious arthropod-borne diseases. This review focuses on recent advances and perspectives towards construction of transgenic mosquitoes refractory to malaria parasites and dengue virus transmission.

  7. Hey! A Mosquito Bit Me!

    Science.gov (United States)

    ... world. There are thousands of different kinds of mosquitoes in many different sizes and colors. The female ... a spine) to lay eggs and produce more mosquitoes. She has a special part of her mouth ...

  8. Null Killing vectors

    International Nuclear Information System (INIS)

    Space-times admitting a null Killing vector are studied, using the Newman-Penrose spin coefficient formalism. The properties of the eigenrays (principal null curves of the Killing bivector) are shown to be related to the twist of the null Killing vector. Among the electrovacs, the ones containing a null Maxwell field turn out to belong to the twistfree class. An electrovac solution is obtained for which the null Killing vector is twisting and has geodesic and shearfree eigenrays. This solution is parameterless and appears to be the field of a zero-mass, spinning and charged source. (author)

  9. Mosquitoes, models, and dengue.

    Science.gov (United States)

    Lifson, A R

    1996-05-01

    In the last 10 years dengue has spread markedly through Latin America and the Caribbean (Dominican Republic, Jamaica, Barbados, Mexico, Guatemala, El Salvador, Honduras, Nicaragua, Costa Rica, Panama, Ecuador, Colombia, Venezuela, and Brazil). The mosquito Aedes aegypti has taken advantage of increased urbanization and crowding to transmit the dengue virus. The mosquito infests tires, cans, and water jars near dwellings. The female mosquito practices multiple, interrupted feeding. Thus, mosquito infesting and feeding practices facilitate dengue transmission in crowded conditions. Factors contributing to the spread of dengue include numbers of infected and susceptible human hosts, strain of dengue virus, size of mosquito population, feeding habits, time from infection to ability to transmit virus for both vector and host, likelihood of virus transmission from human to mosquito to human, and temperature (which affects vector distribution, size, feeding habits, and extrinsic incubation period). Public health models may use simulation models to help them plan or evaluate the potential impact of different intervention strategies and/or of environmental changes (e.g., global warming). Other factors contributing to the dengue epidemic are international travel, urbanization, population growth, crowding, poverty, a weakened public health infrastructure, and limited support for sustained disease control programs. Molecular epidemiology by nucleic acid sequence analysis is another sophisticated technique used to study infectious diseases. It showed that dengue type 3 isolated from Panama and Nicaragua in 1994 was identical to that responsible for the major dengue hemorrhagic fever epidemics in Sri Lanka and India in the 1980s. Public health officials must remember three priorities relevant to dengue and other emerging infections: the need to strengthen surveillance efforts, dedicated and sustained involvement in prevention and control needs at the local level, and a strong public health infrastructure at the international, national, and local levels to maintain support for surveillance and control activities. PMID:8622446

  10. Flavivirus-Mosquito Interactions

    Directory of Open Access Journals (Sweden)

    Yan-Jang S. Huang

    2014-11-01

    Full Text Available The Flavivirus genus is in the family Flaviviridae and is comprised of more than 70 viruses. These viruses have a broad geographic range, circulating on every continent except Antarctica. Mosquito-borne flaviviruses, such as yellow fever virus, dengue virus serotypes 1–4, Japanese encephalitis virus, and West Nile virus are responsible for significant human morbidity and mortality in affected regions. This review focuses on what is known about flavivirus-mosquito interactions and presents key data collected from the field and laboratory-based molecular and ultrastructural evaluations.

  11. Study of mosquito attractants for photo catalytic mosquito trap

    Directory of Open Access Journals (Sweden)

    Dewi Tristantini

    2014-01-01

    Full Text Available Photo catalytic mosquito trap is made of TiO2-Activated Carbon (AC with a certain composition of AC. Research concerns on the heat spectrum which is produced by combination process of existing CO2 and humid air. The purpose of performance testing is to observe capability of this device in trapping mosquitoes related to the air temperature profile for heat spectrum is play important role for attracting mosquitoes. Result shows photo catalytic mosquito trap is more effective than devices which only consist of UV light or stream of CO2 and the humid air. A number of mosquitoes trapped by the photo catalyst coated panel configuration and UV lamps were lit proved far more effective because the heat production from recombination process. A little difference in temperature can be detected by mosquito.   Keywords: Photo Catalytic, Mosquito, Recombination.

  12. Remove Mosquito Habitats

    Science.gov (United States)

    ... monitor standing water sources. Get rid of standing water in rain gutters, old tires, buckets, plastic covers, toys or ... where mosquitoes can breed. Empty and change the water in bird baths, fountains, wading pools, rain barrels and potted plant trays at least once ...

  13. Anopheles arabiensis egg treatment with dieldrin for sex separation leaves residues in male adult mosquitoes that can bioaccumulate in goldfish (Carassius auratus auratus).

    Science.gov (United States)

    Yamada, Hanano; Jandric, Zora; Chhem-Kieth, Sorivan; Vreysen, Marc J B; Rathor, Mohammad N; Gilles, Jeremie R L; Cannavan, Andrew

    2013-12-01

    The sterile insect technique (SIT) is a biological control tactic that is used as a component of area-wide integrated pest management (AW-IPM) programs. The SIT can only be applied against disease-transmitting mosquitoes when only sterile male mosquitoes are released, and the blood-sucking and potentially disease-transmitting females are eliminated from the production line. For Anopheles arabiensis, a potent vector of malaria, a genetic sexing strain was developed whereby females can be eliminated by treating the eggs or larvae with the insecticide dieldrin. To evaluate the presence of dieldrin residues in male mosquitoes designated for SIT releases, a simple, sensitive, and accurate gas chromatography-electron capture detector (GC-ECD) method was developed. In addition, bioaccumulation and food chain transfer of these residues to fish after feeding with treated mosquitoes was demonstrated. The overall recovery from method validation studies was 77.3?±?2.2% (mean?±?relative standard deviation [RSD]) for the mosquitoes, and 99.1?±?4.4% (mean?±?RSD) for the fish. The average dieldrin concentration found in adult male An. arabiensis was 28.1?±?2.9?µg/kg (mean?±?standard deviation [SD]). A range of 23.9?±?1.1?µg/kg to 73.9?±?5.2?µg/kg (mean?±?SD) of dieldrin was found in the fish samples. These findings indicate the need to reassess the environmental and health implications of control operations with a SIT component against An. arabiensis that involves using persistent organochlorines in the sexing process. PMID:23983078

  14. TRANSMISSION MODEL OF CHIKUNGUNYA FEVER IN THE PRESENCE OF TWO SPECIES OF AEDES MOSQUITOES

    Directory of Open Access Journals (Sweden)

    Surapol Naowarat

    2013-01-01

    Full Text Available In 2008 there was a large outbreak of Chikungunya fever in the south of Thailand. Chikungunya fever is a febrile disease transmitted to humans by the bite of infected Aedes mosquitoes. The symptoms of this disease are a sudden onset of a fever, chills, headache, nausea, vomiting, joint pain with or without swelling, low back pain and rash. In this study we study the effects of there being two species of Aedes mosquito (Aedes aegypti and Aedes albopictus present. In this study, we assume that both the human and mosquito populations are constant. A dynamical model of Chikungunya fever is proposed and analyzed. The Routh-Hurwitz criteria are used to determine the stability of the model. The conditions which would lead to either the disease free equilibrium state or the disease endemic equilibrium state to exist is determined. The numerical simulations are done in order to illustrate the behaviors of transmission of disease for different values of parameters. It is shown that the destruction of breeding sites could be an effective method to control this disease.

  15. Cloning, killing, and identity.

    OpenAIRE

    Mcmahan, J.

    1999-01-01

    One potentially valuable use of cloning is to provide a source of tissues or organs for transplantation. The most important objection to this use of cloning is that a human clone would be the sort of entity that it would be seriously wrong to kill. I argue that entities of the sort that you and I essentially are do not begin to exist until around the seventh month of fetal gestation. Therefore to kill a clone prior to that would not be to kill someone like you or me but would be only to preve...

  16. Internecine War Killings

    OpenAIRE

    Fabre, C.

    2012-01-01

    In his recent book Killing in War, McMahan develops a powerful argument for the view that soldiers on opposite sides of a conflict are not morally on a par once the war has started: whether they have the right to kill depends on the justness of their war. In line with just war theory in general, McMahan scrutinizes the ethics of killing the enemy. In this article, I accept McMahan's account, but bring it to bear on the entirely neglected, but nevertheless interesting, issue of what the milita...

  17. Screening of selected ethnomedicinal plants from South Africa for larvicidal activity against the mosquito Anopheles arabiensis

    OpenAIRE

    Maharaj Rajendra; Maharaj Vinesh; Crouch Neil R; Bhagwandin Niresh; Folb Peter I; Pillay Pamisha; Gayaram Reshma

    2012-01-01

    Abstract Background This study was initiated to establish whether any South African ethnomedicinal plants (indigenous or exotic), that have been reported to be used traditionally to repel or kill mosquitoes, exhibit effective mosquito larvicidal properties. Methods Extracts of a selection of plant taxa sourced in South Africa were tested for larvicidal properties in an applicable assay. Thirty 3rd instar Anopheles arabiensis larvae were exposed to various extract types (dichloromethane, dichl...

  18. Radiation biology of mosquitoes

    OpenAIRE

    Gj, Knols Bart; Parker Andrew G; Eh, Helinski Michelle

    2009-01-01

    Abstract There is currently renewed interest in assessing the feasibility of the sterile insect technique (SIT) to control African malaria vectors in designated areas. The SIT relies on the sterilization of males before mass release, with sterilization currently being achieved through the use of ionizing radiation. This paper reviews previous work on radiation sterilization of Anopheles mosquitoes. In general, the pupal stage was irradiated due to ease of handling compared to the adult stage....

  19. A simple non-powered passive trap for the collection of mosquitoes for arbovirus surveillance.

    Science.gov (United States)

    Ritchie, Scott A; Cortis, Giles; Paton, Christopher; Townsend, Michael; Shroyer, Donald; Zborowski, Paul; Hall-Mendelin, Sonja; Van Den Hurk, Andrew F

    2013-01-01

    Mosquitoes often are collected as part of an arbovirus surveillance program. However, trapping and processing of mosquitoes for arbovirus detection is often costly and difficult in remote areas. Most traps, such as the gold standard Center for Disease control light trap, require batteries that must be charged and changed overnight. To overcome this issue we have developed several passive traps for collection of mosquitoes that have no power requirements. The passive traps capture mosquitoes as they follow a CO2 plume up a polyvinyl chloride pipe leading to a clear chamber consisting of a plastic crate. We believe the translucent, clear windows created by the crate inhibits escape. Once inside the crate mosquitoes readily feed on honey-treated Flinders Technology Associates cards that then can be processed by polymerase chain reaction for viral ribonucleic acid. Of the two designs tested, the box or crate-based passive trap (passive box trap, PBT) generally caught more mosquitoes than the cylinder trap. In Latin square field trials in Cairns and Florida, PBTs collected mosquitoes at rates of 50 to 200% of Center for Disease Control model 512 light traps. Mosquito collections by PBTs can be increased by splitting the CO2 gas line so it services two traps, or by placing an octenol lure to the outside of the box. Very large collections can lead to crowding at honey-treated cards, reducing feeding rates. Addition of fipronil to the honey killed mosquitoes and did not impact feeding rates nor the ability to detect Kunjin viral ribonucleic acid by polymerase chain reaction; this could be used to minimize crowding affects on feeding caused by large collections. The passive traps we developed are made from inexpensive, commonly available materials. Passive traps may thus be suitable for collection of mosquitoes and potentially other hematophagous dipterans for pathogen surveillance. PMID:23427669

  20. A Visit to Florida's Mosquito Man

    Science.gov (United States)

    This radio broadcast features an interview with George O'Meara, the world's foremost expert on mosquitoes, who studies mosquito biology and dispenses fun facts (such as: only female mosquitoes bite). There are descriptions of the most aggressive mosquito species, how to tell female mosquitoes from males, and a discussion of landing rates of mosquitoes in the Everglades National Park. The clip is 5 minutes and 30 seconds in length.

  1. Wolbachia surface protein induces innate immune responses in mosquito cells

    Directory of Open Access Journals (Sweden)

    Pinto Sofia B

    2012-01-01

    Full Text Available Abstract Background Wolbachia endosymbiotic bacteria are capable of inducing chronic upregulation of insect immune genes in some situations and this phenotype may influence the transmission of important insect-borne pathogens. However the molecules involved in these interactions have not been characterized. Results Here we show that recombinant Wolbachia Surface Protein (WSP stimulates increased transcription of immune genes in mosquito cells derived from the mosquito Anopheles gambiae, which is naturally uninfected with Wolbachia; at least two of the upregulated genes, TEP1 and APL1, are known to be important in Plasmodium killing in this species. When cells from Aedes albopictus, which is naturally Wolbachia-infected, were challenged with WSP lower levels of upregulation were observed than for the An. gambiae cells. Conclusions We have found that WSP is a strong immune elicitor in a naturally Wolbachia-uninfected mosquito species (Anopheles gambiae while a milder elicitor in a naturally-infected species (Aedes albopictus. Since the WSP of a mosquito non-native (nematode Wolbachia strain was used, these data suggest that there is a generalized tolerance to WSP in Ae. albopictus.

  2. Development of briquettes from natural products for knockdown of mosquitoes

    Directory of Open Access Journals (Sweden)

    Thuku L. Nyakeru

    2012-05-01

    Full Text Available Malaria is a major death cause in many parts of the world. This necessitates the development of alternative ways of curbing the problem. This study focused on the development of briquettes that would knockdown (KD mosquitoes in the course of burning. The briquettes were developed using jatropha seed husks (source of energy, cow dung (binder and pyrethrin (insecticide, which were then tested for their ability to knockdown and kill mosquitoes at Kenya Pyrethrum Board laboratory. The results were analysed using the analysis-of-variance (ANOVA tool. The results showed that a hand pressed mixture of jatropha seed husks, pyrethrin and cow dung (binder in the ratio of 3 g: 0.5 ml: 2 g respectively can cause a 100 % mosquito knockdown within 10 min. and mortality of 97.50 % within 24 hr when burnt indoors. The percentage mosquito knockdown and percentage mortality rate were found to vary significantly with the amount of pyrethrin used. It is expected that the findings of this study will generate new knowledge on briquette development and also contribute to waste management. The research findings will also contribute towards reducing the death rate resulting from malaria.

  3. 33 CFR 117.801 - Newtown Creek, Dutch Kills, English Kills and their tributaries.

    Science.gov (United States)

    2010-07-01

    ... false Newtown Creek, Dutch Kills, English Kills and their tributaries. 117...801 Newtown Creek, Dutch Kills, English Kills and their tributaries. (a...bridges across Newtown Creek, Dutch Kills, English Kills, and their tributaries:...

  4. How killer cells kill.

    Science.gov (United States)

    Young, J D; Cohn, Z A

    1988-01-01

    Killer lymphocytes, the commandos of the immune system, attack tumor cells and cells infected by viruses. They kill by secreting protein molecules that link to form pores in target cells; the cells promptly leak to death. Study of the process may make it possible to improve the killers' efficiency in fighting cancer and such viral infections as AIDS. PMID:3051347

  5. Children Who Kill.

    Science.gov (United States)

    Natale, Jo Anna

    1999-01-01

    Two recent books, "When Good Kids Kill," by Michael D. Kelleher, and "Lost Boys," by James Garbarino, explore how children become killers and suggest ways to reduce our high-pressure society's epidemic levels of youth violence. Physically or psychologically distant parents and unaffirmative media messages are negative influences. (MLH)

  6. Shallow gas blowout kill operations

    International Nuclear Information System (INIS)

    Shallow gas blowouts, as a general class, are the most difficult type of blowout to kill. This paper discusses current industry myths about shallow gas, typical results from a shallow gas blowout that affect the kill operation, kill options and selection criteria, rig selection criteria, and well killing guidelines. The new kill technique of vertical intervention is discussed relative to shallow gas blowouts. Also, a new technique for using horizontal wells in combination with the reservoir flood technique for killing shallow gas, cratered blowouts is explained

  7. Mosquitoes: A Resource Book for the Classroom.

    Science.gov (United States)

    Gillmor, Mary S.; And Others

    This booklet was written for anyone interested in growing mosquitoes and experimenting with them. There are three major sections: (1) rationale for studying mosquitoes, (2) raising mosquitoes, and (3) some scientific findings. The first section describes basic information about mosquitoes. The second section includes information about materials,…

  8. Interspecific killing among mammalian carnivores

    OpenAIRE

    Palomares, Francisco; Caro, T.M.

    1999-01-01

    Interspecific killing among mammalian carnivores is common in nature and accounts for up to 68% of known mortalities in some species. Interactions may be symmetrical (both species kill each other) or asymmetrical (one species kills the other), and in some interactions adults of one species kill young but not adults of the other. There is a positive significant relationship between the body masses of solitary killer species and body masses of their victim species, and grouping species ...

  9. How lymphocytes kill.

    Science.gov (United States)

    Young, L H; Liu, C C; Joag, S; Rafii, S; Young, J D

    1990-01-01

    Cytotoxic T lymphocytes and natural killer cells are potent killers of target cells. These lymphocytes have large cytoplasmic granules containing cytotoxic peptides and other factors. Several of these molecules have been isolated and their functions elucidated. These molecules may be directly involved in the killing of virus-infected and transformed cells as well as in the development of cell-mediated autoimmune disorders. PMID:2184743

  10. Mosquito age and dengue transmission

    Science.gov (United States)

    The Grand Challenges in Global Health Initiative

    This online portal features a research project funded by The Grand Challenges in Global Health Initiative to develop new strategies to control mosquitoes that transmit human disease. Specifically, the project is focused on a method to reduce dengue transmission using naturally occurring bacterial symbionts that reduce mosquito life span. The site includes a background of this work, participating research programs and researchers, project publications, current progress, news and events, and FAQs.

  11. PCR detection of malaria parasites in desiccated Anopheles mosquitoes is uninhibited by storage time and temperature

    Directory of Open Access Journals (Sweden)

    Rider Mark A

    2012-06-01

    Full Text Available Abstract Background Reliable methods to preserve mosquito vectors for malaria studies are necessary for detecting Plasmodium parasites. In field settings, however, maintaining a cold chain of storage from the time of collection until laboratory processing, or accessing other reliable means of sample preservation is often logistically impractical or cost prohibitive. As the Plasmodium infection rate of Anopheles mosquitoes is a central component of the entomological inoculation rate and other indicators of transmission intensity, storage conditions that affect pathogen detection may bias malaria surveillance indicators. This study investigated the effect of storage time and temperature on the ability to detect Plasmodium parasites in desiccated Anopheles mosquitoes by real-time polymerase chain reaction (PCR. Methods Laboratory-infected Anopheles stephensi mosquitoes were chloroform-killed and stored over desiccant for 0, 1, 3, and 6 months while being held at four different temperatures: 28, 37, -20 and -80°C. The detection of Plasmodium DNA was evaluated by real-time PCR amplification of a 111 base pair region of block 4 of the merozoite surface protein. Results Varying the storage time and temperature of desiccated mosquitoes did not impact the sensitivity of parasite detection. A two-way factorial analysis of variance suggested that storage time and temperature were not associated with a loss in the ability to detect parasites. Storage of samples at 28°C resulted in a significant increase in the ability to detect parasite DNA, though no other positive associations were observed between the experimental storage treatments and PCR amplification. Conclusions Cold chain maintenance of desiccated mosquito samples is not necessary for real-time PCR detection of parasite DNA. Though field-collected mosquitoes may be subjected to variable conditions prior to molecular processing, the storage of samples over an inexpensive and logistically accessible desiccant will likely ensure accurate assessment of malaria parasite presence without diminishing PCR-detection of parasites in mosquitoes stored for at least six months.

  12. Infection of adult mosquitoes by the entomopathogenic fungus Erynia conica (Entomophthorales: Entomophthoraceae).

    Science.gov (United States)

    Cuebas-Incle, E L

    1992-12-01

    The infection of adult mosquitoes by the entomopathogenic fungus Erynia conica is presented for the first time. Adult Aedes aegypti were exposed to conidial showers from field-collected chaoborid, tipulid and chironomid cadavers for 24 h under conditions of 100% RH and 15 degrees C. Up to 24% of the adults were killed by the mycosis. Cadavers of Ae. aegypti produced conidia that were infective to other adult Ae. aegypti; however, rates of infection were never more than 12%. Nevertheless, Ae. aegypti served as the laboratory host for E. conica via mosquito-to-mosquito serial passages for up to 6 months. Adult Culex restuans were also susceptible to infection by E. conica. PMID:1474381

  13. A new resting trap to sample fungus-infected mosquitoes, and the pathogenicity of Lecanicillium muscarium to culicid adults.

    Science.gov (United States)

    Luz, Christian; Mnyone, Ladslaus L; Sangusangu, Robert; Lyimo, Issa N; Rocha, Luiz F N; Humber, Richard A; Russell, Tanya L

    2010-10-01

    Some soil-dwelling entomopathogenic fungi that are widely used in pest control are also able to reduce the survival of adult mosquito vectors under laboratory conditions. However, there is still little information about the naturally occurring fungal pathogens affecting culicid mosquitoes. As such, we hypothesized that fungi that already kill mosquitoes in realistic domestic environments could be effective against these vectors in human habitations. A simple, inexpensive, handmade, cylindrical kiln-fired clay pot (30 cm height, 24 cm inner diameter, 0.8-1cm wall thickness) was modified into a trapping device for resting adult mosquitoes and to sample fungus-infected moribund and dead individuals. The entomopathogenic fungus Lecanicillium muscarium was isolated from a dead culicid mosquito collected with this trap in southeastern Tanzania. This isolate is the first L. muscarium reported to occur naturally on adult culicids in Tanzania and was found to be pathogenic also to adults of Aedes aegypti, Anopheles arabiensis and Culex quinquefasciatus under laboratory conditions. The trapping device confirmed its efficacy to sample mosquito-specific fungi in domestic locations and that the isolated fungus might have potential for mosquito control. PMID:20452324

  14. Use of Expanded Polystyrene (EPS and Shredded Waste Polystyrene (SWAP Beads for Control of Mosquitoes

    Directory of Open Access Journals (Sweden)

    A Soltani

    2008-12-01

    Full Text Available Background: Mosquitoes transmit several diseases to human. There are several measures for control of larvae. As part of Integrated Vector Management (IVM program, the utility of floating layers of polystyrene beads (EPS is a po­ten­tial alternative in habitats of mosquito larva. EPS beads prevent oviposition of mosquito as well as killing the im­ma­ture stages by forming a tick layer on the water surface.  They are cheap, environmentally safe and do not need fre­quent application and remain on the surface of water for long time. The objective of the current study was to asses the effectiveness of two types of polystyrene beads of (EPS and (SWAP for control of mosquito larvae under labo­ra­tory conditions."nMethods: Anopheles stephensi and Culex quinquefasciatus were used for experimental purposes. In each tray 250 lar­vae of late 3rd and early 4th instars were introduced. The experiment was conducted on 4 replicates for An. ste­phensi, Cu. quinquefasciatus and combination of both. Emerging of adult mosquitoes were calculated every day until the end of experiments."nResults: Mortality rate and Inhibition of Emerge (IE for Cu. quinquefasciatus, An. stephensi and combination of both spe­cies was 97.8%, 100% and 99.07%, respectively using EPS. In average, EPS was able to kill 98.9% of lar­vae. The fig­ures with SWAP were 63%, 91.05% and 72.65%, respectively. The average mortality for mosquitoes was 75.57%"nConclusion: EPS and SWAP beads can be very effective and practical for elimination of An. stephensi and Cx. quinquefas­ciatus under the laboratory conditions.

  15. Analysis of mosquito larvicidal potential exhibited by vegetative cells of Bacillus thuringiensis subsp. israelensis.

    OpenAIRE

    Walther, C J; Couche, G A; Pfannenstiel, M A; Egan, S. E.; Bivin, L A; Nickerson, K. W.

    1986-01-01

    Vegetative Bacillus thuringiensis subsp. israelensis cells (6 X 10(5)/ml) achieved 100% mortality of Aedes aegypti larvae within 24 h. This larvicidal potential was localized within the cells; the cell-free supernatants did not kill mosquito larvae. However, they did contain a heat-labile hemolysin which was immunologically distinct from the general cytolytic (hemolytic) factor released during solubilization of B. thuringiensis subsp. israelensis crystals. The larvicidal potential of the vege...

  16. Control of pyrethroid-resistant Anopheles gambiae and Culex quinquefasciatus mosquitoes with chlorfenapyr in Benin

    OpenAIRE

    N Guessan, R.; Boko, P.; Odjo, A.; Knols, B. G. J.; Akogbeto, M.; Rowland, M.

    2009-01-01

    Objective To compare the efficacy of chlorfenapyr applied on mosquito nets and as an indoor residual spray against populations of Anopheles gambiae and Culex quinquefasciatus in an area of Benin that shows problematic levels of pyrethroid resistance. Method Eight-week trial conducted in experimental huts. Results Indoor residual spraying killed 82.9% of An. gambiae overall (mean mortality: 79.5%) compared to 53.5% overall (mean mortality: 61.7%) in the hut containing the lower dosed ITN. Anal...

  17. Killing spinor initial data sets

    OpenAIRE

    Gómez-Lobo, Alfonso García-Parrado; Kroon, Juan A. Valiente

    2007-01-01

    A 3+1 decomposition of the twistor and valence-2 Killing spinor equation is made using the space spinor formalism. Conditions on initial data sets for the Einstein vacuum equations are given so that their developments contain solutions to the twistor and/or Killing equations. These lead to the notions of twistor and Killing spinor initial data. These notions are used to obtain a characterisation of initial data sets whose development are of Petrov type N or D.

  18. "The Killing Fields" of Innovation : How to Kill Ideas

    DEFF Research Database (Denmark)

    Ingerslev, Karen

    2014-01-01

    This paper points to seemingly contradicted processes of framing innovation, idea generation and killing ideas. It reports from a yearlong innovation project, where health care professionals explored problems and tested ideas for solutions, regarding a future downsizing of the case hospital. Theories in various ways describe the opening and closing phases of innovation. Exploration and idea generation opens a field of interest, which is then closed by making choices of ideas to further explore in the next opening phase. These choices deliberately kill a lot of ideas. In the innovation project, however, substantial amounts of relevant ideas got killed during opening phases, where the purpose of activities was framed as idea generation. These ideas were either verbally or silently killed, and some in rather contradicted ways: The design and facilitation of brain storming processes lead to clustering of ideas, a design strategy which seemed to kill unique ideas. The reframing of innovation as a radical endeavor killed learning from others for being not innovative. The findings of this paper supplement theories of deliberate killing of ideas by suggesting framing, design and facilitation of innovation as more subtle ways of killing ideas during opening phases.

  19. Inhibition of malaria parasite development in mosquitoes by anti-mosquito-midgut antibodies.

    OpenAIRE

    Lal, A A; Schriefer, M E; Sacci, J.B.; Goldman, I F; Louis-Wileman, V; Collins, W.E.; Azad, A F

    1994-01-01

    The mosquito midgut plays a central role in the development and subsequent transmission of malaria parasites. Using a rodent malaria parasite, Plasmodium berghei, and the mosquito vector Anopheles stephensi, we investigated the effect of anti-mosquito-midgut antibodies on the development of malaria parasites in the mosquito. In agreement with previous studies, we found that mosquitoes that ingested antimidgut antibodies along with infectious parasites had significantly fewer oocysts than mosq...

  20. Killing Spinors -- Beyond Supergravity

    CERN Document Server

    Palomo-Lozano, Alberto

    2012-01-01

    This is a doctoral thesis on the application of techniques originally developed in the programme of characterisation of supersymmetric solutions to Supergravity theories, to finding alternative backgrounds. We start by discussing the concept of a Killing spinor, and how these are paramount to the process of classifying of these aforementioned supersymmetric solutions. Moreover, these geometric objects also have applications when considered in different scenarios (the 'beyond' in the title). In particular, techniques based on a parallelising rule for a spinorial field can be used for obtaining solutions to Einstein-Maxwell-De Sitter theories, as well as a (partial) classification of Lorentzian Einstein-Weyl manifolds, a problem of geometrical interest. The annexe contain an introduction and summary in Spanish language. The appendices discuss the tensorial and spinorial conventions employed, some relevant geometrical information on the scalar manifolds for the matter contents of interest, as well as for the nul...

  1. New Innovations in Biological Control of Mosquitoes.

    Science.gov (United States)

    Biological control of mosquitoes is a component of an integrated pest management strategy and includes general predators, parasites and pathogens. Pathogens of mosquitoes include bacteria, viruses, fungi and protists. The most successful group for applied mosquito control include the bacteria Baci...

  2. Radiation biology of mosquitoes

    Directory of Open Access Journals (Sweden)

    Knols Bart GJ

    2009-11-01

    Full Text Available Abstract There is currently renewed interest in assessing the feasibility of the sterile insect technique (SIT to control African malaria vectors in designated areas. The SIT relies on the sterilization of males before mass release, with sterilization currently being achieved through the use of ionizing radiation. This paper reviews previous work on radiation sterilization of Anopheles mosquitoes. In general, the pupal stage was irradiated due to ease of handling compared to the adult stage. The dose-response curve between the induced sterility and log (dose was shown to be sigmoid, and there was a marked species difference in radiation sensitivity. Mating competitiveness studies have generally been performed under laboratory conditions. The competitiveness of males irradiated at high doses was relatively poor, but with increasing ratios of sterile males, egg hatch could be lowered effectively. Males irradiated as pupae had a lower competitiveness compared to males irradiated as adults, but the use of partially-sterilizing doses has not been studied extensively. Methods to reduce somatic damage during the irradiation process as well as the use of other agents or techniques to induce sterility are discussed. It is concluded that the optimal radiation dose chosen for insects that are to be released during an SIT programme should ensure a balance between induced sterility of males and their field competitiveness, with competitiveness being determined under (semi- field conditions. Self-contained 60Co research irradiators remain the most practical irradiators but these are likely to be replaced in the future by a new generation of high output X ray irradiators.

  3. Chitosan/Interfering RNA nanoparticle mediated gene silencing in disease vector mosquito larvae.

    Science.gov (United States)

    Zhang, Xin; Mysore, Keshava; Flannery, Ellen; Michel, Kristin; Severson, David W; Zhu, Kun Yan; Duman-Scheel, Molly

    2015-01-01

    Vector mosquitoes inflict more human suffering than any other organism-and kill more than one million people each year. The mosquito genome projects facilitated research in new facets of mosquito biology, including functional genetic studies in the primary African malaria vector Anopheles gambiae and the dengue and yellow fever vector Aedes aegypti. RNA interference- (RNAi-) mediated gene silencing has been used to target genes of interest in both of these disease vector mosquito species. Here, we describe a procedure for preparation of chitosan/interfering RNA nanoparticles that are combined with food and ingested by larvae. This technically straightforward, high-throughput, and relatively inexpensive methodology, which is compatible with long double stranded RNA (dsRNA) or small interfering RNA (siRNA) molecules, has been used for the successful knockdown of a number of different genes in A. gambiae and A. aegypti larvae. Following larval feedings, knockdown, which is verified through qRT-PCR or in situ hybridization, can persist at least through the late pupal stage. This methodology may be applicable to a wide variety of mosquito and other insect species, including agricultural pests, as well as other non-model organisms. In addition to its utility in the research laboratory, in the future, chitosan, an inexpensive, non-toxic and biodegradable polymer, could potentially be utilized in the field. PMID:25867635

  4. Pharmacological Validation of an Inward-Rectifier Potassium (Kir) Channel as an Insecticide Target in the Yellow Fever Mosquito Aedes aegypti

    Science.gov (United States)

    Rouhier, Matthew F.; Raphemot, Rene; Denton, Jerod S.; Piermarini, Peter M.

    2014-01-01

    Mosquitoes are important disease vectors that transmit a wide variety of pathogens to humans, including those that cause malaria and dengue fever. Insecticides have traditionally been deployed to control populations of disease-causing mosquitoes, but the emergence of insecticide resistance has severely limited the number of active compounds that are used against mosquitoes. Thus, to improve the control of resistant mosquitoes there is a need to identify new insecticide targets and active compounds for insecticide development. Recently we demonstrated that inward rectifier potassium (Kir) channels and small molecule inhibitors of Kir channels offer promising new molecular targets and active compounds, respectively, for insecticide development. Here we provide pharmacological validation of a specific mosquito Kir channel (AeKir1) in the yellow fever mosquito Aedes aegypti. We show that VU590, a small-molecule inhibitor of mammalian Kir1.1 and Kir7.1 channels, potently inhibits AeKir1 but not another mosquito Kir channel (AeKir2B) in vitro. Moreover, we show that a previously identified inhibitor of AeKir1 (VU573) elicits an unexpected agonistic effect on AeKir2B in vitro. Injection of VU590 into the hemolymph of adult female mosquitoes significantly inhibits their capacity to excrete urine and kills them within 24 h, suggesting a mechanism of action on the excretory system. Importantly, a structurally-related VU590 analog (VU608), which weakly blocks AeKir1 in vitro, has no significant effects on their excretory capacity and does not kill mosquitoes. These observations suggest that the toxic effects of VU590 are associated with its inhibition of AeKir1. PMID:24959745

  5. Mosquito and Blackfly Category Manual.

    Science.gov (United States)

    Bowman, James S.; And Others

    This manual provides information needed to meet the standards for pesticide applicator certification. Section one is concerned with the morphology, life cycle and breeding areas of mosquitoes and the diseases resulting from their presence. The second section covers similar categories in relation to the black fly population. Calculation methods and…

  6. How electroshock weapons kill!

    Science.gov (United States)

    Lundquist, Marjorie

    2010-03-01

    Growing numbers of law enforcement officers now carry an electroshock weapon (ESW). Over 500 U.S. deaths have followed ESW use in the past 26 years; over 450 of these deaths followed use of an electromuscular disruptor in the past 9 years. Most training courses teach that ESWs are safe; that they can kill only by the direct effect of electric current on the heart; and that a death following use of an ESW always has some other cause. All these teachings are false! The last was disproved by Lundquist.^1 Williams^2 ruled out direct electrical effects as a cause of almost all the 213 deaths he studied, leaving disruption of normal physiological processes as the only alternative explanation. Careful study of all such deaths identifies 4 different ways that death has or could have been brought about by the ESW: kidney failure following rhabdomyolysis [rare]; cardiac arrest from hyperkalemia following rhabdomyolysis [undocumented]; lactic acid-induced ventricular fibrillation [conclusive proof impossible]; and [most common] anoxia from so much lactic acid in the circulating blood that it acts as an oxygen scavenger, continuously depleting the blood of oxygen until most of the lactate has been metabolized. ^1M. Lundquist, BAPS 54(1) K1.270(2009). ^2Howard E. Williams, Taser Electronic Control Devices and Sudden In-Custody Death, 2008.

  7. Evaluation of indoor residual spraying with the pyrrole insecticide chlorfenapyr against pyrethroid-susceptible Anopheles arabiensis and pyrethroid-resistant Culex quinquefasciatus mosquitoes.

    Science.gov (United States)

    Oxborough, R M; Kitau, J; Matowo, J; Mndeme, R; Feston, E; Boko, P; Odjo, A; Metonnou, C G; Irish, S; N'guessan, R; Mosha, F W; Rowland, M W

    2010-10-01

    Chlorfenapyr is a pyrrole insecticide with a unique non-neurological mode of action. Laboratory bioassays of chlorfenapyr comparing the mortality of pyrethroid-susceptible and -resistant Anopheles gambiae s.s. and Culex quinquefasciatus mosquitoes indicated that operational cross-resistance is unlikely to occur (resistance ratio ranged between 0 and 2.1). Three trials of chlorfenapyr indoor residual spraying were undertaken in experimental huts in an area of rice irrigation in northern Tanzania that supports breeding of A. arabiensis. Daily mosquito collections were undertaken to assess product performance primarily in terms of mortality. In the second trial, 250mg/m(2) and 500mg/m(2) chlorfenapyr were tested for residual efficacy over 6 months. Both dosages killed 54% of C. quinquefasciatus, whilst for A. arabiensis 250mg/m(2) killed 48% compared with 41% for 500mg/m(2); mortality was as high at the end of the trial as at the beginning. In the third trial, 250mg/m(2) chlorfenapyr was compared with the pyrethroid alpha-cypermethrin dosed at 30mg/m(2). Chlorfenapyr performance was equivalent to the pyrethroid against A. arabiensis, with both insecticides killing 50% of mosquitoes. Chlorfenapyr killed a significantly higher proportion of pyrethroid-resistant C. quinquefasciatus (56%) compared with alpha-cypermethrin (17%). Chlorfenapyr has the potential to be an important addition to the limited arsenal of public health insecticides for indoor residual control of A. arabiensis and pyrethroid-resistant species of mosquito. PMID:20850003

  8. The unexpected importance of mosquito oviposition behaviour for malaria: non-productive larval habitats can be sources for malaria transmission

    Directory of Open Access Journals (Sweden)

    Flahault Antoine

    2005-05-01

    Full Text Available Abstract Background Mosquitoes commute between blood-meal hosts and water. Thus, heterogeneity in human biting reflects underlying spatial heterogeneity in the distribution and suitability of larval habitat as well as inherent differences in the attractiveness, suitability and distribution of blood-meal hosts. One of the possible strategies of malaria control is to identify local vector species and then attack water bodies that contain their larvae. Methods Biting and host seeking, not oviposition, have been the focus of most previous studies of mosquitoes and malaria transmission. This study presents a mathematical model that incorporates mosquito oviposition behaviour. Results The model demonstrates that oviposition is one potential factor explaining heterogeneous biting and vector distribution in a landscape with a heterogeneous distribution of larval habitat. Adult female mosquitoes tend to aggregate around places where they oviposit, thereby increasing the risk of malaria, regardless of the suitability of the habitat for larval development. Thus, a water body may be unsuitable for adult mosquito emergence, but simultaneously, be a source for human malaria. Conclusion Larval density may be a misleading indicator of a habitat's importance for malaria control. Even if mosquitoes could be lured to oviposit in sprayed larval habitats, this would not necessarily mitigate – and might aggravate – the risk of malaria transmission. Forcing mosquitoes to fly away from humans in search of larval habitat may be a more efficient way to reduce the risk of malaria than killing larvae. Thus, draining, fouling, or filling standing water where mosquitoes oviposit can be more effective than applying larvicide.

  9. Free flight of the mosquito Aedes aegypti

    OpenAIRE

    Iams, S. M.

    2012-01-01

    High speed video observations of free flying male Aedes aegypti mosquitoes, the dengue and yellow fever vector, along with custom measurement methods, enable measurement of wingbeat frequency, body position and body orientation of mosquitoes during flight. We find these mosquitoes flap their wings at approximately 850 Hz. We also generate body yaw, body pitch and wing deviation measurements with standard deviations of less than 1 degree and find that sideways velocity and ac...

  10. North American Wetlands and Mosquito Control

    Directory of Open Access Journals (Sweden)

    Gabrielle E. Sakolsky-Hoopes

    2012-12-01

    Full Text Available Wetlands are valuable habitats that provide important social, economic, and ecological services such as flood control, water quality improvement, carbon sequestration, pollutant removal, and primary/secondary production export to terrestrial and aquatic food chains. There is disagreement about the need for mosquito control in wetlands and about the techniques utilized for mosquito abatement and their impacts upon wetlands ecosystems. Mosquito control in wetlands is a complex issue influenced by numerous factors, including many hard to quantify elements such as human perceptions, cultural predispositions, and political climate. In spite of considerable progress during the last decades, habitat protection and environmentally sound habitat management still remain inextricably tied to politics and economics. Furthermore, the connections are often complex, and occur at several levels, ranging from local businesses and politicians, to national governments and multinational institutions. Education is the key to lasting wetlands conservation. Integrated mosquito abatement strategies incorporate many approaches and practicable options, as described herein, and need to be well-defined, effective, and ecologically and economically sound for the wetland type and for the mosquito species of concern. The approach will certainly differ in response to disease outbreaks caused by mosquito-vectored pathogens versus quality of life issues caused by nuisance-biting mosquitoes. In this contribution, we provide an overview of the ecological setting and context for mosquito control in wetlands, present pertinent information on wetlands mosquitoes, review the mosquito abatement options available for current wetlands managers and mosquito control professionals, and outline some necessary considerations when devising mosquito control strategies. Although the emphasis is on North American wetlands, most of the material is applicable to wetlands everywhere.

  11. North American Wetlands and Mosquito Control

    OpenAIRE

    Gabrielle E. Sakolsky-Hoopes; Laderman, Aimlee D.; Joe Berg; Sheila M. O'Connell; C. Roxanne Connelly; Roger J. Wolfe; Walton, William E.; Rey, Jorge R.

    2012-01-01

    Wetlands are valuable habitats that provide important social, economic, and ecological services such as flood control, water quality improvement, carbon sequestration, pollutant removal, and primary/secondary production export to terrestrial and aquatic food chains. There is disagreement about the need for mosquito control in wetlands and about the techniques utilized for mosquito abatement and their impacts upon wetlands ecosystems. Mosquito control in wetlands is a complex issue influenced ...

  12. Wolbachia-a foe for mosquitoes

    OpenAIRE

    Guruprasad, Nadipinayakanahalli Munikrishnappa; Jalali, Sushil Kumar; Puttaraju, Hosagavi Puttegowda

    2014-01-01

    Mosquitoes act as vectors for a wide range of viral and parasitic infectious diseases such as malaria, dengue, Chickungunya, lymphatic filariasis, Japanese encephalitis and West Nile virus in humans as well as in animals. Although a wide range of insecticides are used to control mosquitoes, it has only resulted in development of resistance to such insecticides. The evolution of insecticide resistance and lack of vaccines for many mosquito-borne diseases have made these arthropods highly harmf...

  13. Ecological immunology of mosquito–malaria interactions

    OpenAIRE

    Tripet, Fre?de?ric; Aboagye-antwi, Fred; Hurd, Hilary

    2008-01-01

    More than a century after the discovery of the complex life cycle of its causative agent, malaria remains a major health problem. Understanding mosquito–malaria interactions could lead to breakthroughs in malaria control. Novel strategies, such as the design of transgenic mosquitoes refractory to Plasmodium, or design of human vaccines emulating mosquito resistance to the parasite, require extensive knowledge of processes involved in immune responses and of microevolutionary mechanisms that...

  14. Do malaria parasites manipulate mosquitoes?

    OpenAIRE

    Cator, Lauren J; Lynch, Pennelope A.; Read, Andrew F.; Matthew B. Thomas

    2012-01-01

    Malaria parasites have been suggested to alter the behavior of mosquito vectors to increase the likelihood of transmission. Some empirical evidence supports this hypothesis, yet the role of manipulation is ignored in most epidemiological models, and behavioral differences between infected and uninfected females are not considered in the development or implementation of control measures. We suggest that this disconnect exists because the link between behavioral alteration and actual transmissi...

  15. Genetically Modified Mosquito: Myth and Reality

    Directory of Open Access Journals (Sweden)

    Teh Su Yean

    2013-02-01

    Full Text Available Sterile Insect Technique (SIT has been applied successfully in some agricultural pest control programs in the past, but in many cases, success has not been sustainable in the long run. Various attempts have been made to duplicate this limited success SIT application in agriculture to other areas of applications, particularly in vector control. For example, a recent mosquito control program has been initiated in Malaysia to eliminate dengue-mosquitoes Aedes aegypti by releasing large amount of genetically modified GM male mosquitoes into the field to outcompete the wild male mosquitoes. Field experimental data that has been made available in the literature is limited, rendering it difficult to make independent assessment on its short-term efficacy and long-term sustainability of this GM control strategy. This paper presents a preliminary assessment of the effectiveness of GM mosquito in controlling dengue mosquito population by means of model simulations via DEER (Dengue Encephalitis Eradication Routines. Preliminary results indicate negative conclusion regarding the effectiveness of GM mosquitoes in controlling wild A. aegypti population over the long-term. Essentially, significant reduction of wild mosquito population is possible only if large over-flooding ratios are applied. Further, repeated releases must be maintained over an infinite time horizon to continue to sustain low population of mosquitoes. Major difficulty remains to be resolved. In particular, in-depth costbenefit analysis on this control program is essential to ensure long-term institutional and social support.

  16. Estudio de un brote de enfermedades trasmitidas por alimentos en una instalación hotelera. Municipio Varadero. 2009 / Study of an outbreak of diseases transmitted by food in a hotel. Varadero, 2009

    Scientific Electronic Library Online (English)

    Milvian, Morales Cardona; Dayami, Núñez González; Beatriz, Guerra González; Tamara, Parra Rodríguez; Osvaldo, Morales Hernández.

    2011-02-01

    Full Text Available Las enfermedades transmitidas por alimentos constituyen un problema cada vez más importante a nivel internacional. Según la Organización Mundial de la Salud, entre un 70 y un 80 % de los casos de diarrea que se producen se deben a la ingestión de agua y alimentos contaminados, constituyendo actualme [...] nte un desafío, puesto que se desconoce su real incidencia. Motivados por la necesidad de incrementar la vigilancia de los brotes de estas enfermedades y de realizar un adecuado estudios de los mismos, se realizó una investigación epidemiológica observacional descriptiva de un brote de enfermedades transmitidas por alimentos, ocurrido en una instalación hotelera en Varadero, en agosto de 2009. La muestra estuvo constituida por 58 turistas: 29 sanos e igual número de enfermos, a los que se le aplicó la encuesta validada para estudiar estos eventos; de ella se obtuvo la información. Se calculó la Mediana para determinar período de incubación, haciéndolo corresponder con el posible agente etiológico. Se halló la tasa de ataque específica, la cual indicó el alimento sospechoso. Se realizó estudios de laboratorio a muestras de alimentos, especímenes y a manipuladores de alimentos. Se demostró que la no aplicación de las buenas prácticas de manufactura de los alimentos, unido al deterioro del cuadro higiénico de la instalación, fue la causa directa del brote; el agente causal la Samonella D, aislada en el revoltillo y en los especímenes. Abstract in english The diseases transmitted by food are a more and more important problem at the international level. According to the World Health Organization, between the 70 and the 80 % of the diarrheic cases are due to the ingestion of contaminated water and food, being a challenge nowadays, because its real inci [...] dence is unknown. Motivated for the necessity of increasing the surveillance of these diseases outbreaks and adequately studying them, we carried out the descriptive, observational, epidemiologic survey of an outbreak of diseases transmitted by foods that took place in a hotel in Varadero, in August 2009. The sample was formed by 59 tourists: 28 healthy and the same number of sick. They applied a survey validated to study these events; the information was taken from it. The media was calculated to determine the incubation period, making it correspond with the possible etiologic agent. We calculated the specific attack rate, indicating the suspecting food. We made laboratory studies of food samples, specimens and food manipulators. It was showed that not applying good practices of food elaboration, together with the worsening of the health situation of the installation, was the direct cause of the outbreak; the causal agent was the Salmonella D, isolated in the scrambled eggs and the specimens.

  17. Estudio de un brote de enfermedades trasmitidas por alimentos en una instalación hotelera. Municipio Varadero. 2009 Study of an outbreak of diseases transmitted by food in a hotel. Varadero, 2009

    Directory of Open Access Journals (Sweden)

    Milvian Morales Cardona

    2011-02-01

    Full Text Available Las enfermedades transmitidas por alimentos constituyen un problema cada vez más importante a nivel internacional. Según la Organización Mundial de la Salud, entre un 70 y un 80 % de los casos de diarrea que se producen se deben a la ingestión de agua y alimentos contaminados, constituyendo actualmente un desafío, puesto que se desconoce su real incidencia. Motivados por la necesidad de incrementar la vigilancia de los brotes de estas enfermedades y de realizar un adecuado estudios de los mismos, se realizó una investigación epidemiológica observacional descriptiva de un brote de enfermedades transmitidas por alimentos, ocurrido en una instalación hotelera en Varadero, en agosto de 2009. La muestra estuvo constituida por 58 turistas: 29 sanos e igual número de enfermos, a los que se le aplicó la encuesta validada para estudiar estos eventos; de ella se obtuvo la información. Se calculó la Mediana para determinar período de incubación, haciéndolo corresponder con el posible agente etiológico. Se halló la tasa de ataque específica, la cual indicó el alimento sospechoso. Se realizó estudios de laboratorio a muestras de alimentos, especímenes y a manipuladores de alimentos. Se demostró que la no aplicación de las buenas prácticas de manufactura de los alimentos, unido al deterioro del cuadro higiénico de la instalación, fue la causa directa del brote; el agente causal la Samonella D, aislada en el revoltillo y en los especímenes.The diseases transmitted by food are a more and more important problem at the international level. According to the World Health Organization, between the 70 and the 80 % of the diarrheic cases are due to the ingestion of contaminated water and food, being a challenge nowadays, because its real incidence is unknown. Motivated for the necessity of increasing the surveillance of these diseases outbreaks and adequately studying them, we carried out the descriptive, observational, epidemiologic survey of an outbreak of diseases transmitted by foods that took place in a hotel in Varadero, in August 2009. The sample was formed by 59 tourists: 28 healthy and the same number of sick. They applied a survey validated to study these events; the information was taken from it. The media was calculated to determine the incubation period, making it correspond with the possible etiologic agent. We calculated the specific attack rate, indicating the suspecting food. We made laboratory studies of food samples, specimens and food manipulators. It was showed that not applying good practices of food elaboration, together with the worsening of the health situation of the installation, was the direct cause of the outbreak; the causal agent was the Salmonella D, isolated in the scrambled eggs and the specimens.

  18. Novel Methods for Mosquito Control using RNAi.

    Science.gov (United States)

    The discovery and development of novel insecticides for vector control is a primary focus of toxicology research conducted at the Mosquito and Fly Research Unit, Gainesville, FL. Targeting critical genes/proteins in mosquitoes using RNA interference (RNAi) is being investigated as a method to devel...

  19. Free flight of the mosquito Aedes aegypti

    CERN Document Server

    Iams, S M

    2012-01-01

    High speed video observations of free flying male Aedes aegypti mosquitoes, the dengue and yellow fever vector, along with custom measurement methods, enable measurement of wingbeat frequency, body position and body orientation of mosquitoes during flight. We find these mosquitoes flap their wings at approximately 850 Hz. We also generate body yaw, body pitch and wing deviation measurements with standard deviations of less than 1 degree and find that sideways velocity and acceleration are important components of mosquito motion. Rapid turns involving changes in flight direction often involve large sideways accelerations. These do not correspond to commensurate changes in body heading, and the insect's flight direction and body heading are decoupled during flight. These findings call in to question the role of yaw control in mosquito flight. In addition, using orientation data, we find that sideways accelerations are well explained by roll-based rotation of the lift vector. In contrast, the insect's body pitch...

  20. Ecology of vector mosquitoes in Sri Lanka--suggestions for future mosquito control in rice ecosystems.

    Science.gov (United States)

    Yasuoka, Junko; Levins, Richard

    2007-07-01

    Mosquito-borne diseases are a major public health threat in Asia. To explore effective mosquito control strategies in rice ecosystems from the ecological point of view, we carried out ecological analyses of vector mosquitoes in Sri Lanka. During the 18-month study period, 14 Anopheles, 11 Culex, 5 Aedes, 2 Mansonia, and 1 Armigeres species were collected, most of which are disease vectors for malaria, filariasis, Japanese encephalitis, or dengue in Sri Lanka and elsewhere in Asia. The density and occurrence of Anopheles and Culex species were the highest in seepage pools and paddy fields, where the majority of niche overlaps between larval mosquito and aquatic insect species were observed. All 7 aquatic insect species, which are larval mosquito predators, overlapped their niche with both Anopheles and Culex larvae. This suggests that conserving these aquatic insect species could be effective in controlling mosquito vectors in the study site. Correlations between several climatic factors and mosquito density were also analyzed, and weather conditions, including higher temperature, lower relative humidity, and higher wind velocity, were found to affect mosquito oviposition, propagation, and survival. These findings deepen our understanding of mosquito ecology and will strengthen future mosquito control strategies in rice ecosystems in Asia. PMID:17883002

  1. Ecology of mosquitoes of Midwestern Nigeria

    Directory of Open Access Journals (Sweden)

    Godwin R.A. Okogun, Jude C. Anosike, Anthony N. Okere & Bethran E.B. Nwoke

    2005-03-01

    Full Text Available Background & objectives: The ecology and distribution of various mosquito species is important inthe determination of mosquito vector abundance and associated diseases prevalence. The distributionof various mosquito genera in natural and artificial habitats and their relative species abundancewas studied between August 2002 and July 2003 in three foci (Uromi, Ekpoma and Auchi comprisingthe Esan and Etsako regions of Midwestern Nigeria.Methods: Sampling was carried out by the method of Hopkins (1952 by dipping using a pipette orladle depending on container types. Pooled contents of smaller containers were sampled with a pondnet. All breeding sources of mosquito larvae were grouped into five (5 depending on their nature,constitution and the physiochemical properties. Artificial mosquito cultures were also carried out infour different container types; plastics, metal cans, earthenware pots and bamboo strips, in parts oftwo different macro habitats subdivided into area of high human activities (AHHA and areas ofderived/secondary vegetation (ADSV. Environmental temperatures, rainfall and relative humiditywere monitored during the study.Results: The present study revealed 17 mosquito species belonging to three genera (Anopheles,Culex and Aedes which are potential vectors of four human diseases in the areas surveyed. A total of736 mosquito larvae were encountered in artificial sources and 568 larvae were harvested from naturalsources. Pools, plastics and metal cans were the predominant artificial sources of mosquito larvae.Conclusion: The contribution of human activities and increasing environmental modification to thebreeding of human disease vector mosquitoes is of importance and selective vector control measuresincluding larviciding are recommended particularly before onset of rainy season

  2. Malaria Parasites Produce Volatile Mosquito Attractants

    Science.gov (United States)

    Kelly, Megan; Su, Chih-Ying; Schaber, Chad; Crowley, Jan R.; Hsu, Fong-Fu; Carlson, John R.

    2015-01-01

    ABSTRACT The malaria parasite Plasmodium falciparum contains a nonphotosynthetic plastid organelle that possesses plant-like metabolic pathways. Plants use the plastidial isoprenoid biosynthesis pathway to produce volatile odorants, known as terpenes. In this work, we describe the volatile chemical profile of cultured malaria parasites. Among the identified compounds are several plant-like terpenes and terpene derivatives, including known mosquito attractants. We establish the molecular identity of the odorant receptors of the malaria mosquito vector Anopheles gambiae, which responds to these compounds. The malaria parasite produces volatile signals that are recognized by mosquitoes and may thereby mediate host attraction and facilitate transmission. PMID:25805727

  3. Can mosquitoes fly in the rain?

    CERN Document Server

    Dickerson, Andrew; Madhavan, Nihar; Hu, David

    2011-01-01

    Collisions with raindrops are one of many obstacles insects face during flight. In this fluid dynamics video, we present a series of high-speed films of impacts between mosquitoes and raindrops. We also present drop impacts upon insect mimics, which are unsupported styrofoam balls of the same mass as mosquitoes. High-speed videography and particle tracking during collision are employed to determine the insect position versus time. We determine the magnitude of acceleration by considering the momentum transfer and impact duration. Experiments with live mosquitoes indicate a surprising ability to quickly recover flight post-collision, despite accelerations of 30-300 gravities over durations of 1 ms.

  4. WOMEN'S RIGHTS VIOLATION: HONOUR KILLINGS

    Directory of Open Access Journals (Sweden)

    CRISTINA OTOVESCU FRASIE

    2011-04-01

    Full Text Available In this study I have presented the domestic violence concept and the situation regarding the observing of woman’s rights in Syria. We have also evidenced the juridical aspects regarding the honor killing directed against women after the modification of the article 548 from the Penal Code changed by the President al-Asad on July the 1st 2009. The data offered by NGOs have been of great help for the elaboration of the study as also the statistic data presented in Thara E-Magazine regarding the cities where had been done the honor killings and their number, the instrument of the murder, the age of the victim, and the motives for the murders. It must be noticed that, lately, the Government fought for the observing of the woman’s rights and promoted he gender equality by appointing women in leading positions, including the vice-president one.

  5. Evolution equations for Killing fields

    International Nuclear Information System (INIS)

    The problem of finding necessary and sufficient conditions on the Cauchy data for Einstein equations which insure the existence of Killing fields in a neighborhood of an initial hypersurface has been considered recently by Berezdivin, Coll, and Moncrief. Nevertheless, it can be shown that the evolution equations obtained in all these cases are of nonstrictly hyperbolic type, and, thus, the Cauchy data must belong to a special class of functions. We prove here that, for the vacuum and Einstein--Maxwell space--times and in a coordinate independent way, one can always choose, as evolution equations for the Killing fields, a strictly hyperbolic system: The above theorems can be thus extended to all Cauchy data for which the Einstein evolution problem has been proved to be well set

  6. Rapid nectar-meal effects on a predator's capacity to kill mosquitoes.

    Science.gov (United States)

    Carvell, Georgina E; Kuja, Josiah O; Jackson, Robert R

    2015-05-01

    Using Evarcha culicivora, an East African jumping spider (Salticidae), we investigate how nectar meals function in concert with predation specifically at the juvenile stage between emerging from the egg sac and the first encounter with prey. Using plants and using artificial nectar consisting of sugar alone or sugar plus amino acids, we show that the plant species (Lantana camara, Ricinus communis, Parthenium hysterophorus), the particular sugars in the artificial nectar (sucrose, fructose, glucose, maltose), the concentration of sugar (20%, 5%, 1%) and the duration of pre-feeding fasts (3 days, 6 days) influence the spider's prey-capture proficiency on the next day after the nectar meal. However, there were no significant effects of amino acids. Our findings suggest that benefits from nectar feeding are derived primarily from access to particular sugars, with fructose and sucrose being the most beneficial, glucose being intermediate and maltose being no better than a water-only control. PMID:26064651

  7. Fog spontaneously folds mosquito wings

    Science.gov (United States)

    Dickerson, Andrew K.; Liu, Xing; Zhu, Ting; Hu, David L.

    2015-02-01

    The flexibility of insect wings confers aerodynamic benefits, but can also present a hazard if exposed to fog or dew. Fog can cause water to accumulate on wings, bending them into tight taco shapes and rendering them useless for flight. In this combined experimental and theoretical study, we use high-speed video to film the spontaneous folding of isolated mosquito wings due to the evaporation of a water drop. We predict shapes of the deformed wing using two-dimensional elastica theory, considering both surface tension and Laplace pressure. We also recommend fold-resistant geometries for the wings of flapping micro-aerial vehicles. Our work reveals the mechanism of insect wing folding and provides a framework for further study of capillarity-driven folding in both natural and biomimetic systems at small scales.

  8. Mosquito transcriptome changes and filarial worm resistance in Armigeres subalbatus

    Directory of Open Access Journals (Sweden)

    Chen Cheng-Chen

    2007-12-01

    Full Text Available Abstract Background Armigeres subalbatus is a natural vector of the filarial worm Brugia pahangi, but it rapidly and proficiently kills Brugia malayi microfilariae by melanotic encapsulation. Because B. malayi and B. pahangi are morphologically and biologically similar, the Armigeres-Brugia system serves as a valuable model for studying the resistance mechanisms in mosquito vectors. We have initiated transcriptome profiling studies in Ar. subalbatus to identify molecular components involved in B. malayi refractoriness. Results These initial studies assessed the transcriptional response of Ar. subalbatus to B. malayi at 1, 3, 6, 12, 24, 48, and 72 hrs after an infective blood feed. In this investigation, we initiated the first holistic study conducted on the anti-filarial worm immune response in order to effectively explore the functional roles of immune-response genes following a natural exposure to the parasite. Studies assessing the transcriptional response revealed the involvement of unknown and conserved unknowns, cytoskeletal and structural components, and stress and immune responsive factors. The data show that the anti-filarial worm immune response by Ar. subalbatus to be a highly complex, tissue-specific process involving varied effector responses working in concert with blood cell-mediated melanization. Conclusion This initial study provides a foundation and direction for future studies, which will more fully dissect the nature of the anti-filarial worm immune response in this mosquito-parasite system. The study also argues for continued studies with RNA generated from both hemocytes and whole bodies to fully expound the nature of the anti-filarial worm immune response.

  9. The entomopathogenic fungus Beauveria bassiana reduces instantaneous blood feeding in wild multi-insecticide-resistant Culex quinquefasciatus mosquitoes in Benin, West Africa

    Directory of Open Access Journals (Sweden)

    Howard Annabel FV

    2010-09-01

    Full Text Available Abstract Background Mosquito-borne diseases are still a major health risk in many developing countries, and the emergence of multi-insecticide-resistant mosquitoes is threatening the future of vector control. Therefore, new tools that can manage resistant mosquitoes are required. Laboratory studies show that entomopathogenic fungi can kill insecticide-resistant malaria vectors but this needs to be verified in the field. Methods The present study investigated whether these fungi will be effective at infecting, killing and/or modifying the behaviour of wild multi-insecticide-resistant West African mosquitoes. The entomopathogenic fungi Metarhizium anisopliae and Beauveria bassiana were separately applied to white polyester window netting and used in combination with either a permethrin-treated or untreated bednet in an experimental hut trial. Untreated nets were used because we wanted to test the effect of fungus alone and in combination with an insecticide to examine any potential additive or synergistic effects. Results In total, 1125 female mosquitoes were collected during the hut trial, mainly Culex quinquefasciatus Say. Unfortunately, not enough wild Anopheles gambiae Giles were collected to allow the effect the fungi may have on this malaria vector to be analysed. None of the treatment combinations caused significantly increased mortality of Cx. quinquefasciatus when compared to the control hut. The only significant behaviour modification found was a reduction in blood feeding by Cx. quinquefasciatus, caused by the permethrin and B. bassiana treatments, although no additive effect was seen in the B. bassiana and permethrin combination treatment. Beauveria bassiana did not repel blood foraging mosquitoes either in the laboratory or field. Conclusions This is the first time that an entomopathogenic fungus has been shown to reduce blood feeding of wild mosquitoes. This behaviour modification indicates that B. bassiana could potentially be a new mosquito control tool effective at reducing disease transmission, although further field work in areas with filariasis transmission should be carried out to verify this. In addition, work targeting malaria vector mosquitoes should be carried out to see if these mosquitoes manifest the same behaviour modification after infection with B. bassiana conidia.

  10. Slow Death by Many Mosquito Bites

    CERN Document Server

    Redner, S

    2014-01-01

    We study the dynamics of a single diffusing particle (a "man") with diffusivity $D_M$ that is attacked by another diffusing particle (a "mosquito") with fixed diffusivity $D_m$. Each time the mosquito meets and bites the man, the diffusivity of the man is reduced by a fixed amount, while the diffusivity of the mosquito is unchanged. The mosquito is also displaced by a small distance $\\pm a$ with respect to the man after each encounter. The man is defined as dead when $D_M$ reaches zero. At the moment when the man dies, his probability distribution of displacements $x$ is given by a Cauchy form, which asymptotically decays as $x^{-2}$, while the distribution of times $t$ when the man dies asymptotically decays as $t^{-3/2}$, which has the same form as the one-dimensional first-passage probability.

  11. Can mosquitoes fly in the rain?

    OpenAIRE

    Dickerson, Andrew; Shankles, Peter; Madhavan, Nihar; Hu, David

    2011-01-01

    Collisions with raindrops are one of many obstacles insects face during flight. In this fluid dynamics video, we present a series of high-speed films of impacts between mosquitoes and raindrops. We also present drop impacts upon insect mimics, which are unsupported styrofoam balls of the same mass as mosquitoes. High-speed videography and particle tracking during collision are employed to determine the insect position versus time. We determine the magnitude of acceleration b...

  12. Aedes Mosquito Species in Western Saudi Arabia

    OpenAIRE

    Alikhan, Masroor; Ghamdi, Khalid Al; Mahyoub, Jazem Abdullah

    2014-01-01

    The Aedes Meigen (Diptera: Culicidae) mosquito species populations in the western region of Saudi Arabia, especially in and around Jeddah, are increasing, therefore increasing susceptibility of humans to the dengue virus. An extensive survey was carried out for one year, and four species were identified with the help of different pictorial keys available. The identification was based on morphological characteristics of adult female Aedes mosquitoes.

  13. Genetically Modified Mosquito: Myth and Reality

    OpenAIRE

    Teh Su Yean; Koh Hock Lye; Yeap Kiew Lee

    2013-01-01

    Sterile Insect Technique (SIT) has been applied successfully in some agricultural pest control programs in the past, but in many cases, success has not been sustainable in the long run. Various attempts have been made to duplicate this limited success SIT application in agriculture to other areas of applications, particularly in vector control. For example, a recent mosquito control program has been initiated in Malaysia to eliminate dengue-mosquitoes Aedes aegypti by releasing large amount o...

  14. Killing(-Yano) Tensors in String Theory

    CERN Document Server

    Chervonyi, Yuri

    2015-01-01

    We construct the Killing(-Yano) tensors for a large class of charged black holes in higher dimensions and study general properties of such tensors, in particular, their behavior under string dualities. Killing(-Yano) tensors encode the symmetries beyond isometries, which lead to insights into dynamics of particles and fields on a given geometry by providing a set of conserved quantities. By analyzing the eigenvalues of the Killing tensor, we provide a prescription for constructing several conserved quantities starting from a single object, and we demonstrate that Killing tensors in higher dimensions are always associated with ellipsoidal coordinates. We also determine the transformations of the Killing(-Yano) tensors under string dualities, and find the unique modification of the Killing-Yano equation consistent with these symmetries. These results are used to construct the explicit form of the Killing(-Yano) tensors for the Myers-Perry black hole in arbitrary number of dimensions and for its charged version.

  15. Chikungunya virus and its mosquito vectors.

    Science.gov (United States)

    Higgs, Stephen; Vanlandingham, Dana

    2015-04-01

    Chikungunya virus (CHIKV), a mosquito-borne alphavirus of increasing public health significance, has caused large epidemics in Africa and the Indian Ocean basin; now it is spreading throughout the Americas. The primary vectors of CHIKV are Aedes (Ae.) aegypti and, after the introduction of a mutation in the E1 envelope protein gene, the highly anthropophilic and geographically widespread Ae. albopictus mosquito. We review here research efforts to characterize the viral genetic basis of mosquito-vector interactions, the use of RNA interference and other strategies for the control of CHIKV in mosquitoes, and the potentiation of CHIKV infection by mosquito saliva. Over the past decade, CHIKV has emerged on a truly global scale. Since 2013, CHIKV transmission has been reported throughout the Caribbean region, in North America, and in Central and South American countries, including Brazil, Columbia, Costa Rica, El Salvador, French Guiana, Guatemala, Guyana, Nicaragua, Panama, Suriname, and Venezuela. Closing the gaps in our knowledge of driving factors behind the rapid geographic expansion of CHIKV should be considered a research priority. The abundance of multiple primate species in many of these countries, together with species of mosquito that have never been exposed to CHIKV, may provide opportunities for this highly adaptable virus to establish sylvatic cycles that to date have not been seen outside of Africa. The short-term and long-term ecological consequences of such transmission cycles, including the impact on wildlife and people living in these areas, are completely unknown. PMID:25674945

  16. Repelentes electrónicos contra mosquitos: propaganda y realidad

    Directory of Open Access Journals (Sweden)

    Frank Coro

    1998-08-01

    Full Text Available Se presenta una revisión bibliográfica acerca del uso de dispositivos electroacústicos con supuesta acción repelente sobre las hembras de diferentes especies de mosquitos hematófagos. Se dan 15 referencias directas y 2 indirectas, en todas se concluye que estos dispositivos no protegen a quienes los portan de las picadas de los mosquitos. Se dan los nombres de 9 de los dispositivos probados, así como de 16 de las principales especies de mosquitos presentes en las pruebas de campo. Estas pruebas de campo se han realizado en condiciones ecológicas muy diferentes, que van desde alaska hasta el África Ecuatorial. También se menciona el efecto potencialmente dañino al hombre de los dispositivos que emiten frecuencias a alta intensidad.A bibliographic review about the use of electroacustic devices with a supposed repellent action on the females of different species of hematophagous mosquitoes is presented. 15 direct references and 2 indirect ones are given, in which it is concluded that these devices do not protect those who have them from the stings of mosquitoes. The names of 9 of the tested devices as well as of 16 of the main species of mosquitoes present in the field tests are mentioned. These tests have been carried out in very different ecological conditions from Alaska to Equatorial Africa. It is also stressed that the high intensity ultrasonic frequencies emitted by these devices produces a potentially harmful effect on man.

  17. Loss of protection with insecticide-treated nets against pyrethroid-resistant Culex quinquefasciatus mosquitoes once nets become holed: an experimental hut study

    Directory of Open Access Journals (Sweden)

    Irish SR

    2008-06-01

    Full Text Available Abstract Background An important advantage of pyrethroid-treated nets over untreated nets is that once nets become worn or holed a pyrethroid treatment will normally restore protection. The capacity of pyrethroids to kill or irritate any mosquito that comes into contact with the net and prevent penetration of holes or feeding through the sides are the main reasons why treated nets continue to provide protection despite their condition deteriorating over time. Pyrethroid resistance is a growing problem among Anopheline and Culicine mosquitoes in many parts of Africa. When mosquitoes become resistant the capacity of treated nets to provide protection might be diminished, particularly when holed. An experimental hut trial against pyrethroid-resistant Culex quinquefasciatus was therefore undertaken in southern Benin using a series of intact and holed nets, both untreated and treated, to assess any loss of protection as nets deteriorate with use and time. Results There was loss of protection when untreated nets became holed; the proportion of mosquitoes blood feeding increased from 36.2% when nets were intact to between 59.7% and 68.5% when nets were holed to differing extents. The proportion of mosquitoes blood feeding when treated nets were intact was 29.4% which increased to 43.6–57.4% when nets were holed. The greater the number of holes the greater the loss of protection regardless of whether nets were untreated or treated. Mosquito mortality in huts with untreated nets was 12.9–13.6%; treatment induced mortality was less than 12%. The exiting rate of mosquitoes into the verandas was higher in huts with intact nets. Conclusion As nets deteriorate with use and become increasingly holed the capacity of pyrethroid treatments to restore protection is greatly diminished against resistant Culex quinquefasciatus mosquitoes.

  18. Immunopathological Features Developing in the Mosquito Midgut after Feeding on Anopheles gambiae Mucin-1 / Interleukin-12 cDNA Immunized Mice / Desarrollo de Características Inmunopatológicas en el Intestino Medio del Mosquito Después de Alimentarse de Ratones Inmunizados con Mucina-1 / Interleucina-12 ADNc de Anopheles gambiae

    Scientific Electronic Library Online (English)

    Wilfred E, Injera; Elphantus W, Kabiru; Michael M, Gicheru; John I, Githure; John C, Beier.

    2013-03-01

    Full Text Available El intestino medio es el órgano al cual pasa la sangre consumida por el mosquito y donde, mediante una membrana peritrófica secretada por el epitelio, esta sangre es mantenida durante la digestión y absorción. El intestino del mosquito está revestido por microvellosidades llenas de actina que son ex [...] puestas a las complejas condiciones en torno a la luz intestinal, tales como la abrasión producida por partículas de alimentos, hidrolasas digestivas y el ataque de patógenos y parásitos que son tomados en la sangre consumida. Estas microvellosidades se protegen de estos efectos mediante la matriz peritrófica, el glicocálix y las proteínas de mucina que revisten las superficies epiteliales. La inmunización con AgMUC1/IL-12 ADNc en ratones BALB/c ha demostrado ser útil para matar los mosquitos cuando se alimentan de estos ratones. La mucina es una de las proteínas producidas en el intestino medio del mosquito después de consumir sangre. La fina estructura del epitelio del intestino interactúa con factores inmunes tales como anticuerpos o células inmunes es de especial importancia para interpretar los eventos tempranos en la interacción entre el revestimiento del intestino medio y los componentes inmunológicos específicos presentes en la sangre de ratones BALB/c inmunizados con AgMUC1/IL-12 cDNA. Después de observar mediante microscopías de luz, electrónica de barrido y de transmisión las características de secciones del intestino medio del mosquito Anopheles gambiae alimentado de ratones BALB/c inmunizados con AgMUC1/IL-12 cDNA, mecanismos inmunes mediados por citotoxicidad celular dependiente de anticuerpos (ADCC) podrían ser los responsables de matar a los mosquitos. Los procesos necróticos y apoptóticos que pueden ser la causa de la muerte del mosquito tienen lugar en las células que recubren el epitelio del intestino medio. Abstract in english The mosquito midgut is the organ into which the blood meal passes and in which, within a peritrophic membrane secreted by the epithelium, the blood is retained during digestion and absorption. The mosquito midgut is lined with an actin filled microvilli that are exposed to the harsh environment of t [...] he gut lumen such as food particle abrasion, digestive hydrolases and attack by pathogens and parasites that are taken in by the blood meal. These microvilli are protected them these effects by the peritrophic matrix, the glycocalyx and the mucin proteins that line their epithelial surfaces. Immunization of BALB/c mice with AgMUC1/IL-12 cDNA has been shown to kill mosquitoes when fed on these mice. Mucin is one of the proteins produced in the mosquito midgut after a blood meal. The fine structure of the mosquito midgut epithelium interacting with immune factors such as antibodies or immune cells is of special significance for interpreting early events in the interaction between the mosquito midgut lining and the specific immune components present in the blood of AgMUC1/IL-12 cDNA immunized BALB/c mice. Following bright light microscopy, scanning electron and transmission electron microscopic observations of the features seen in mosquito midgut sections from An. gambiae mosquitoes fed on BALB/c mice immunized with AgMUC1/IL-12 cDNA, the most likely immune mechanisms responsible for mosquito killing could be cell mediated, most likely antibody dependent cellular cytotoxicity. Both necrotic and apoptotic processes that could be the cause of mosquito death were seen to take place in the cells lining the midgut epithelium.

  19. Attract-and-kill strategy. Laboratory studies on hatched larvae of Culex pipiens.

    Science.gov (United States)

    Michaelakis, Antonios; Mihou, Anastasia P; Koliopoulos, George; Couladouros, Elias A

    2007-10-01

    The attract-and-kill strategy is a new pest management technique that presupposes the intelligent combination of an attracting agent (e.g. pheromone) and a killing agent (e.g. insecticide). In the present study, the potential combination of the microencapsulated synthetic oviposition pheromone 6-acetoxy-5-hexadecanolide with an insecticide has been tested. Initially, polyurea microcapsules containing 6-acetoxy-5-hexadecanolide, the synthetic mixture of diastereomers of the oviposition pheromone of the mosquito species Culex quinquefasciatus Say (Diptera: Culicidae), were studied. Laboratory bioassays were performed to confirm the bioactivity of the microencapsulated pheromone on the oviposition activity of Culex pipiens L. biotype molestus Førskal (Diptera: Culicidae) with the aim of determining the optimum dose for oviposition response. Its effect was dose dependent, revealing an optimum dose of 300 mg of dried microcapsules. Attractancy over time was also studied. The microencapsulated pheromone was found to be sufficiently attractive to gravid female mosquitoes for a period of 40 days. Finally, the combination of the synthetic pheromone with the control agent temephos showed both an acceptable oviposition activity and sufficient larvicidal effect. PMID:17708518

  20. Prospects for the mosquito baculovirus CuniNPV as a tool for mosquito control.

    Science.gov (United States)

    Becnel, James J

    2006-09-01

    CuniNPV is a pathogen of Culex mosquitoes, vectors of West Nile virus and other forms of encephalitis. Successful development of CuniNPV requires an efficient production system and formulated product that incorporates magnesium, an essential component for transmission. It may be possible to develop mosquito baculoviruses as a new type of biopesticide by microencapsulating the virus and magnesium into formulations that would be effective regardless of the water quality. In addition, this new insight on transmission may facilitate the discovery and development of additional baculoviruses for the control of other important mosquito vectors. Biological mining of the CuniNPV genome and investigations to understand virus-mosquito interactions at the molecular level offer exciting possibilities for the development of novel mosquito control strategies and tools. Understanding the molecular mechanisms of infection will provide the opportunity to devise new control strategies, for example, compromising the defensive systems of the mosquito (proteases for the peritrophic matrix) or exploiting receptors used by the virus to specifically deliver toxins to mosquito larvae via the midgut. As additional baculovirus genomes become available, comparative genomics could lead to a more informed understanding of how the virus exploits its host as well as the factors responsible for the genus-specific host range of most known mosquito baculoviruses. PMID:17067056

  1. WOMEN'S RIGHTS VIOLATION: HONOUR KILLINGS

    OpenAIRE

    CRISTINA OTOVESCU FRASIE

    2011-01-01

    In this study I have presented the domestic violence concept and the situation regarding the observing of woman’s rights in Syria. We have also evidenced the juridical aspects regarding the honor killing directed against women after the modification of the article 548 from the Penal Code changed by the President al-Asad on July the 1st 2009. The data offered by NGOs have been of great help for the elaboration of the study as also the statistic data presented in Thara E-Magazine regarding th...

  2. How To Kill a Penguin

    OpenAIRE

    Haisch, U

    2007-01-01

    Within constrained minimal-flavor-violation the large destructive flavor-changing Z-penguin managed to survive eradication so far. We give a incisive description of how to kill it using the precision measurements of the Z -> b anti-b pseudo observables. The derived stringent range for the non-standard contribution to the universal Inami-Lim function C leads to tight two-sided limits for the branching ratios of all Z-penguin dominated flavor-changing K- and B-decays.

  3. Optimization and synthesis of silver nanoparticles using Isaria fumosorosea against human vector mosquitoes.

    Science.gov (United States)

    Banu, A Najitha; Balasubramanian, C

    2014-10-01

    The efficacy of silver generated larvicide with the help of entomopathogenic fungi, Isaria fumosorosea (Ifr) against major vector mosquitoes Culex quinquefasciatus and Aedes aegypti. The Ifr-silver nanoparticles (AgNPs) were characterized structurally and functionally using UV-visible spectrophotometer followed by scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) spectroscopy and Fourier transform infrared (FTIR) spectra. The optimum pH (alkaline), temperature (30 °C) and agitation (150 rpm) for AgNP synthesis and its stability were confirmed through colour change. Ae. aegypti larvae (I-IV instars) were found highly susceptible to synthesized AgNPs than the larvae of Cx. quinquefasciatus. However, the mortality rate was indirectly proportional to the larval instar and the concentration. The lethal concentration that kills 50% of the exposed larvae (LC50) and lethal concentration that kills 90% of the exposed larvae (LC90) values of the tested concentration are 0.240, 0 0.075.337, 0.430, 0.652 and 1.219, 2.210, 2.453, 2.916; 0.065, 0.075, 0.098, 0.137 and 0.558, 0.709, 0.949, 1.278 ppm with respect to 0.03 to 1.00 ppm of Ifr-AgNPs against first, second, third and fourth instars of Cx. quinquefasciatus and Ae. aegypti, respectively. This is the first report for synthesis of AgNPs using Ifr against human vector mosquitoes. Hence, Ifr-AgNPs would be significantly used as a potent mosquito larvicide. PMID:25085201

  4. Repellent, Irritant and Toxic Effects of 20 Plant Extracts on Adults of the Malaria Vector Anopheles gambiae Mosquito

    Science.gov (United States)

    Deletre, Emilie; Martin, Thibaud; Campagne, Pascal; Bourguet, Denis; Cadin, Andy; Menut, Chantal; Bonafos, Romain; Chandre, Fabrice

    2013-01-01

    Pyrethroid insecticides induce an excito-repellent effect that reduces contact between humans and mosquitoes. Insecticide use is expected to lower the risk of pathogen transmission, particularly when impregnated on long-lasting treated bednets. When applied at low doses, pyrethroids have a toxic effect, however the development of pyrethroid resistance in several mosquito species may jeopardize these beneficial effects. The need to find additional compounds, either to kill disease-carrying mosquitoes or to prevent mosquito contact with humans, therefore arises. In laboratory conditions, the effects (i.e., repellent, irritant and toxic) of 20 plant extracts, mainly essential oils, were assessed on adults of Anopheles gambiae, a primary vector of malaria. Their effects were compared to those of DEET and permethrin, used as positive controls. Most plant extracts had irritant, repellent and/or toxic effects on An. gambiae adults. The most promising extracts, i.e. those combining the three types of effects, were from Cymbopogon winterianus, Cinnamomum zeylanicum and Thymus vulgaris. The irritant, repellent and toxic effects occurred apparently independently of each other, and the behavioural response of adult An. gambiae was significantly influenced by the concentration of the plant extracts. Mechanisms underlying repellency might, therefore, differ from those underlying irritancy and toxicity. The utility of the efficient plant extracts for vector control as an alternative to pyrethroids may thus be envisaged. PMID:24376515

  5. Hyperthermic cell killing and radiosensitization

    International Nuclear Information System (INIS)

    Hyperthermic inhibition of DNA repair may not only cause radiosensitization, but might also play a substantial role in the mechanism of cell killing by heat alone, e.g. by the inhibition of post-replication repair. If cell survival after hyperthermia or a combined heat plus radiation treatment is determined by the impairment of only one specific step of DNA repair, the degree of impairment has to correlate with survival after heat alone or in combination with radiation, under a variety of conditions that alter cell survival. The protective effect of thermotolerance and erythritol, and sensitization by step-down heating and procaine were used as tools to study whether such a correlation could be found for the inhibition of strand-break repair or DNA polymerase inactivation. During this study a small number of DNA strand breaks (or alkali-labile lesions) was observed to arise from hyperthermia alone. The relationship of these lesions to hyperthermic cell killing was further investigated. 524 refs.; 59 figs.; 15 tabs

  6. Does mosquito control have an effect on mosquito-borne disease? The case of Ross River virus disease and mosquito management in Queensland, Australia.

    Science.gov (United States)

    Tomerini, Deanna M; Dale, Pat E; Sipe, Neil

    2011-03-01

    We examined the relationship between types of mosquito control programs and the mosquito-borne Ross River virus (RRV) disease in Queensland, Australia. Mosquito control information was collected through a survey of the responsible agencies (local governments), and RRV disease notification data were provided by the Queensland state health authority. The study developed a typology of mosquito control programs, based on the approaches used. Based on the analysis of data on RRV disease rates between mosquito control types within 4 climatic regions, each region had different combinations of mosquito control strategies in their programs; there were also general similarities in the relationship between program types and RRV rates between the regions. The long-term RRV disease rates were lower in areas where the mosquito control program included pre-emptive (rather than reactive) surveillance based on an extensive (rather than incomplete) knowledge of mosquito habitats, and where treatment of both saltwater and freshwater habitats (compared to only saltwater habitats, in coastal areas) occurred. The data indicate that mosquito control is an effective public health intervention to reduce mosquito-borne disease; hence, climate change adaptation strategies should ensure that adequate resources are available for effective vector control so as to manage the risk of mosquito-borne diseases. PMID:21476446

  7. The trial detection of malaria sporozoit in field-collected mosquito by immunoradiometric assay in Thailand

    International Nuclear Information System (INIS)

    The sporozoite rate, species of parasite and vector are important in the epidemiology of malaria. The investigation of sporozoite by dissection and examination under a microscope is time-consuming and it could be done only on freshly killed mosquitoes. Immunoradiometric assay (IRMA) that can detect, identify and quantify malaria sporozoite (Zavala et al., 1982) was therefore applied to detect sporozoite in laboratory-maintained Anopheles dirus and wild-caught mosquitoes. Study on P. falciparum-infected An. dirus showed that the circumsporozoite (CS) antigen was first found in the abdomen on the 10th day post-infection, whilst the sporozoites were examined in salivary glands from day 15 onwards. The malaria infection in wild-caught mosquitoes were investigated in Anopheles spp collected by human baites from three endemic areas in Thailand. Since the sporozoite rate refers to the presence of sporozoite in the salivary gland, then only head-thorax part of the specimens were detected by IRMA to prevent an exaggeration over the true results. It was found that none of mosquitoes collected from Phrae was positive for malaria. Four out of 1243 An. dirus among eight species collected from Chantaburi were positive for P. falciparum with sporozoites ranged from 270 to 3875. Of all ten species collected from Kanchanaburi, two and one out of 3123 An. minimus were positive for P. falciparum and P. vivax with sporozoites found in head-thorax portions were 1880, 2380 and 1026 respectively. It is evident that the IRMA is suitable for the investigation of malaria sporozoites in this region. The application of this technique in the further epidemiological study is in progress

  8. Male-killing in African butterflies

    OpenAIRE

    Sami Saeed M. Hassan; Eihab Idris

    2013-01-01

    Female-biased sex ratios occur in many insect species as a consequence of infection by maternally-inherited male-killing bacterial endosymbionts. In this paper, we revise the research conducted on the phenomenon of male-killing in African nymphalid butterflies, with special focus on the cases of Danaus chrysippus, Acraea encedon and Acraea encedana. The evolution of male-killing in each case was addressed, together with the phylogeny of male-killers that were identified from this group. Moreo...

  9. Fish Kills in Ireland in 1989

    OpenAIRE

    Moriarty, C.

    1990-01-01

    The final estimate for the number of fish kills in 1989 was 111. The increase in 1989 is largely accounted for by the exceptional warm weather conditions which prevailed. Details of all the incidents are given in the following pages. When these are analysed some very significant facts emerge. The number of fish kills while higher than in 1988 (50 kills) was about nine percent lower than in 1987 (122 kills). Low water due to dry weather conditions was the most important factor in 1989 raising ...

  10. A kill curve for Phanerozoic marine species

    Science.gov (United States)

    Raup, D. M.

    1991-01-01

    A kill curve for Phanerozoic species is developed from an analysis of the stratigraphic ranges of 17,621 genera, as compiled by Sepkoski. The kill curve shows that a typical species' risk of extinction varies greatly, with most time intervals being characterized by very low risk. The mean extinction rate of 0.25/m.y. is thus a mixture of long periods of negligible extinction and occasional pulses of much higher rate. Because the kill curve is merely a description of the fossil record, it does not speak directly to the causes of extinction. The kill curve may be useful, however, to li inverted question markmit choices of extinction mechanisms.

  11. Do topical repellents divert mosquitoes within a community?

    OpenAIRE

    Maia Marta; Sangoro Peter; Thele Max; Turner Elizabeth; Moore Sarah

    2012-01-01

    Repellents are compounds which interfere with the mosquito’s olfactory system hindering them to identify their hosts and succeeding in taking a blood-meal [1]. However, repellents do not eliminate the host-seeking mosquitoes, they simply reduce human-vector contact. Consequently, there is a possibility that individuals, who do not use repellents, experience more bites than usual because mosquitoes are diverted from the repellent users. The objective of this study was to measure if diversion...

  12. The role of mosquito behaviour on parasite transmission

    OpenAIRE

    Ma, Brian Oh-bong

    2010-01-01

    I use a combination of theory and experiments to explore the role of various aspects of mosquito behaviour on the ability of mosquitoes to transmit parasites. Special focus is given to the mosquito Anopheles gambiae s.s., the principal vector for Plasmodium falciparum, a parasite that causes human malaria. Female mosquitoes require host blood for egg production, but also use sugar from nectar sources; however, the extent of sugar use is poorly understood. Sugar can be used to fuel somatic mai...

  13. Conditioning Individual Mosquitoes to an Odor: Sex, Source, and Time

    OpenAIRE

    Michelle R. Sanford; Tomberlin, Jeffery K

    2011-01-01

    Olfactory conditioning of mosquitoes may have important implications for vector-pathogen-host dynamics. If mosquitoes learn about specific host attributes associated with pathogen infection, it may help to explain the heterogeneity of biting and disease patterns observed in the field. Sugar-feeding is a requirement for survival in both male and female mosquitoes. It provides a starting point for learning research in mosquitoes that avoids the confounding factors associated with the observer b...

  14. Enhanced Survival of Plasmodium-Infected Mosquitoes during Starvation

    OpenAIRE

    Zhao, Yang O; Kurscheid, Sebastian; Zhang, Yue; Liu, Lei; Zhang,Lili; Loeliger, Kelsey; FIKRIG, EROL

    2012-01-01

    Plasmodium spp. are pathogenic to their vertebrate hosts and also apparently, impose a fitness cost on their insect vectors. We show here, however, that Plasmodium-infected mosquitoes survive starvation significantly better than uninfected mosquitoes. This survival advantage during starvation is associated with higher energy resource storage that infected mosquitoes accumulate during period of Plasmodium oocyst development. Microarray analysis revealed that the metabolism of sated mosquitoes ...

  15. Aedes Mosquito Saliva Modulates Rift Valley Fever Virus Pathogenicity

    OpenAIRE

    Le Coupanec, Alain; Babin, Divya; Fiette, Laurence; Jouvion, Gre?gory; Ave, Patrick; Misse, Dorothee; Bouloy, Michèle; Choumet, Valerie

    2013-01-01

    BACKGROUND: Rift Valley fever (RVF) is a severe mosquito-borne disease affecting humans and domestic ruminants. Mosquito saliva contains compounds that counteract the hemostatic, inflammatory, and immune responses of the host. Modulation of these defensive responses may facilitate virus infection. Indeed, Aedes mosquito saliva played a crucial role in the vector's capacity to effectively transfer arboviruses such as the Cache Valley and West Nile viruses. The role of mosquito saliva in the tr...

  16. Mosquito larvicidal activity of thymol from essential oil of Coleus aromaticus Benth. against Culex tritaeniorhynchus, Aedes albopictus, and Anopheles subpictus (Diptera: Culicidae).

    Science.gov (United States)

    Govindarajan, Marimuthu; Sivakumar, Rajamohan; Rajeswary, Mohan; Veerakumar, Kaliyan

    2013-11-01

    Diseases transmitted by blood-feeding mosquitoes, such as dengue fever, dengue hemorrhagic fever, Japanese encephalitis, malaria, and filariasis, are increasing in prevalence, particularly in tropical and subtropical zones. To control mosquitoes and mosquito-borne diseases, which have a worldwide health and economic impacts, synthetic insecticide-based interventions are still necessary, particularly in situations of epidemic outbreak and sudden increases of adult mosquitoes. However, the indiscriminate use of conventional insecticides is fostering multifarious problems like widespread development of insecticide resistance, toxic hazards to mammals, undesirable effects on nontarget organisms, and environmental pollution. The aim of this research was to evaluate the toxicity of mosquito larvicidal activity of essential oil from Coleus aromaticus and its pure isolated constituent thymol against larvae of Culex tritaeniorhynchus, Aedes albopictus, and Anopheles subpictus. The chemical composition of the essential oil was analyzed using gas chromatography-mass spectroscopy. A total of 14 components of the essential oil of C. aromaticus were identified. The major chemical components identified were thymol (82.68%), terpinen-4-ol (3.2%), and trans-Caryophyllene (3.18%). Twenty-five early third instar larvae of C. tritaeniorhynchus, A. albopictus, and A. subpictus were exposed and assayed in the laboratory. Thymol and essential oil were tested in concentrations of 10, 20, 30, 40, and 50 and 30, 60, 90, 120, and 150 ppm, respectively. The larval mortality was observed after 24 h of treatment. The thymol had a significant toxic effect against early third-stage larvae of C. tritaeniorhynchus, A. albopictus, and A. subpictus with an LC50 values of 28.19, 24.83, and 22.06 ?g/mL respectively, whereas the essential oil of C. aromaticus had an LC50 values of 72.70, 67.98, and 60.31 ?g/mL, respectively. No mortality was observed in controls. The Chi-square values were significant at p < 0.05 level. The result indicated that the essential oil of C. aromaticus and the isolated constituent have a potential for use in control of C. tritaeniorhynchus, A. albopictus, and A. subpictus larvae and could be useful in search of newer, safer, and more effective natural compounds as larvicides. PMID:23933878

  17. 75 FR 62469 - Drawbridge Operation Regulations; Newtown Creek, Dutch Kills, English Kills, and Their...

    Science.gov (United States)

    2010-10-12

    ...Coast Guard 33 CFR Part 117 [Docket No. USCG-2010-0907] Drawbridge Operation Regulations; Newtown Creek, Dutch Kills, English Kills, and Their Tributaries, NY, Maintenance AGENCY: Coast Guard, DHS. ACTION: Notice of temporary deviation from...

  18. 75 FR 30299 - Drawbridge Operation Regulations; Newtown Creek, Dutch Kills, English Kills, and Their...

    Science.gov (United States)

    2010-06-01

    ...Coast Guard 33 CFR Part 117 [Docket No. USCG-2010-0355] Drawbridge Operation Regulations; Newtown Creek, Dutch Kills, English Kills, and Their Tributaries, NY, Maintenance AGENCY: Coast Guard, DHS. ACTION: Notice of temporary deviation from...

  19. The biology of malarial parasite in the mosquito: a review

    Directory of Open Access Journals (Sweden)

    Amauri Braga Simonetti

    1996-10-01

    Full Text Available The purpose of this review is to summarize the biology of Plasmodium in the mosquito including recent data to contribute to better understanding of the developmental interaction between mosquito and malarial parasite. The entire sporogonic cycle is discussed taking into consideration different parasite/vector interactions and factors affecting parasite development to the mosquito.

  20. Molecular Perspectives on the Genetics of Mosquitoes

    International Nuclear Information System (INIS)

    Mosquitoes have been a focus of scientific study since the turn of the century, when they were first linked with human diseases. This review concentrates on the three most intensely studied genera, Anopheles, Culex, and Aedes. These genera include the principal vectors of three major groups of human pathogens: malaria parasites of the genus Plasmodium, filarial worms of the genera Wuchereria and Brugia, and numerous arboviruses. Anophelines are the only mosquitoes known to transmit human malaria parasites, a group of organisms that may be responsible for more morbidity and mortality worldwide than any other human pathogen. Anophelines also transmit filarial worms, as do Culex and Aedes species. Among the 14 or more different mosquito genera known to harbor arboviruses (Mattingly, 1973), the most important are Culex and Aedes, which include the principal vectors of yellow fever, dengue, and most encephalitis-causing arboviruses.

  1. Evaluation of botanicals as repellents against mosquitoes

    Directory of Open Access Journals (Sweden)

    N.G. Das, I. Baruah, P.K. Talukdar & S.C. Das

    2003-03-01

    Full Text Available Repellent properties of three plant extracts—essential oil (steam distillate of Zanthoxylumlimonella (fruits, Citrus aurantifolia (leaf and petroleum ether extract of Z. limonella (fruitswere evaluated as repellent against Aedes (S. albopictus mosquitoes in mustard (Dhara and coconut(Parachute oil base under laboratory conditions. Three concentrations—10, 20 and 30% of therepellents were evaluated. Repellents in mustard oil afforded longer protection time against thebites of Aedes (S. albopictus mosquitoes than those in coconut oil. At 30% concentration, 296–304 min protection time was achieved by the test repellents in mustard oil base while repellents incoconut oil exhibited 223.5–245 min protection time at the same concentration. Oil of Z. limonellagave the highest protection time against the bites of Aedes (S. albopictus mosquitoes at all theconcentrations than other herbal repellents tested both in mustard and coconut oil.

  2. The Influence of Diet on the Use of Near-Infrared Spectroscopy to Determine the Age of Female Aedes aegypti Mosquitoes.

    Science.gov (United States)

    Liebman, Kelly; Swamidoss, Isabel; Vizcaino, Lucrecia; Lenhart, Audrey; Dowell, Floyd; Wirtz, Robert

    2015-05-01

    Interventions targeting adult mosquitoes are used to combat transmission of vector-borne diseases, including dengue. Without available vaccines, targeting the primary vector, Aedes aegypti, is essential to prevent transmission. Older mosquitoes (? 7 days) are of greatest epidemiological significance due to the 7-day extrinsic incubation period of the virus. Age-grading of female mosquitoes is necessary to identify post-intervention changes in mosquito population age structure. We developed models using near-infrared spectroscopy (NIRS) to age-grade adult female Ae. aegypti. To determine if diet affects the ability of NIRS models to predict age, two identical larval groups were fed either fish food or infant cereal. Adult females were separated and fed sugar water ± blood, resulting in four experimental groups. Females were killed 1, 4, 7, 10, 13, or 16 days postemergence. The head/thorax of each mosquito was scanned using a near-infrared spectrometer. Scans from each group were analyzed, and multiple models were developed using partial least squares regression. The best model included all experimental groups, and positively predicted the age group (diets can affect the ability of NIRS models to accurately assign age categories to female Ae. aegypti. PMID:25802436

  3. NO BUG: biobased mosquitoes repellent textiles

    OpenAIRE

    Ciera, Lucy Wanjiru; Nierstrasz, Vincent; Clerck, Karen; Van Langenhove, Lieva

    2011-01-01

    This research work is part of the FP7 No-Bug project (Novel release system and biobased utilities for insect repellent textiles). The main interest of the project is personal protective textiles against insects (mosquitoes) for application not only in tropical areas where vector borne diseases are a major threat to the public health but also in European countries where the presence of mosquitoes can be nuisance. Malaria and dengue fever are well known diseases that cause a lot of deaths in th...

  4. FIELD EVALUATION OF CDC AND MOSQUITO MAGNET® X TRAPS BAITED WITH DRY ICE, CO2 SACHET, AND OCTENOL AGAINST MOSQUITOES

    Science.gov (United States)

    CDC light traps and Mosquito Magnet® X (MMX) traps baited with dry ice, octenol, and a new formulation of CO2 (granular) were evaluated against mosquitoes in the field. The results showed that the MMX traps (68.6%) baited with dry ice collected more mosquitoes, compared to the CDC light traps (32.4%...

  5. Building a Better Mosquito: Identifying the Genes Enabling Malaria and Dengue Fever Resistance in A. gambiae and A. aegypti Mosquitoes

    OpenAIRE

    Dimopoulos, George

    2007-01-01

    In this interview, George Dimopoulos focuses on the physiological mechanisms used by mosquitoes to combat Plasmodium falciparum and dengue virus infections. Explanation is given for how key refractory genes, those genes conferring resistance to vector pathogens, are identified in the mosquito and how this knowledge can be used to generate transgenic mosquitoes that are unable to carry the malaria parasite or dengue virus.

  6. Cambio climático en España y riesgo de enfermedades infecciosas y parasitarias transmitidas por artrópodos y roedores / Climate Change in Spain and Risk of Infectious and Parasitic Diseases Transmitted by Arthropods and Rodents

    Scientific Electronic Library Online (English)

    Rogelio, López-Vélez; Ricardo, Molina Moreno.

    2005-04-01

    Full Text Available Por la proximidad con el continente africano, siendo lugar de tránsito obligado de aves migratorias y personas, y por las condiciones climáticas, cercanas a las de zonas donde hay transmisión de enfermedades vectoriales, España es un país en el que este tipo de enfermedades podrían verse potenciadas [...] por el cambio climático. El posible riesgo vendría por extensión geográfica de vectores ya establecidos o por la importación e instalación de vectores sub-tropicales adaptados a sobrevivir en climas menos cálidos y más secos. Hipotéticamente, las enfermedades vectoriales susceptibles de ser influidas por el cambio climático en España serían aquellas transmitidas por dípteros como dengue, encefalitis del Nilo occidental, fiebre del valle del Rift, malaria y leishmaniosis; las transmitidas por garrapatas como la fiebre de Congo Crimea, encefalitis por garrapata, enfermedad de Lyme, fiebre botonosa y fiebre recurrente endémica; y las transmitidas por roedores. Pero la mayor y más factible amenaza sería la instauración del mosquito Aedes albopictus, que sería capaz de transmitir enfermedades virales como la del Nilo occidental o el dengue. Pero para el establecimiento de auténticas áreas de endemia se necesitaría la conjunción de otros factores, tales como el aflujo masivo y simultáneo de reservorios animales o humanos y el deterioro de las condiciones socio-sanitarias y de los servicios de Salud Pública. Abstract in english Due to Spain's being located near Africa, being a stopping-off point for migrating birds and individuals and due to its climate conditions, nearing those of areas where there are vector-borne diseases, this is a country where this type of diseases could taken on greater importance due to the climate [...] change. The possible risk would result from the geographical spread of already established vectors or due to subtropical vectors adapted to surviving in cooler, dried climates being imported and taking up residence. Hypothetically, the vector-borne diseases subject to be influenced by the climate change in Spain would be those transmitted by dipterans, such as dengue fever, West Nile encephalitis, Rift Valley fever, malaria and leishmaniasis; tick-transmitted diseases, such as Crimean-Congo hemorrhagic fever, tick-borne encephalitis, Lyme disease, spotted fever and endemic relapsing fever; and rodent-transmitted diseases. But the greatest, most viable threat would be the Aedes albopictus mosquito, which would be capable of transmitting viral diseases such as West Nile encephalitis or dengue fever, taking up residence. But, for actual areas of endemia being established, a combination of other factors, such as the massive, simultaneous influx of animal or human reservoirs and the deterioration of the social healthcare conditions and of the Public Health services.

  7. Hypersurface homogeneous Killing spinor space–times

    International Nuclear Information System (INIS)

    I present a complete list of hypersurface homogeneous space–times admitting a non-null valence two Killing spinor, including a new class admitting only exceptional Killing tensors. A connection is established with the classification of locally rotationally symmetric or boost symmetric space–times. (paper)

  8. Larvicidal and phytochemical properties of Callistemon rigidus R. Br. (Myrtaceae leaf solvent extracts against three vector mosquitoes

    Directory of Open Access Journals (Sweden)

    Danga Yinyang Simon Pierre

    2014-08-01

    Full Text Available Background & objectives: Due to ever-growing insecticide resistance in mosquito vectors and environmental contamination by synthetic insecticides, plants may be a source of alternative agents for mosquito control. Therefore, the present investigation involved the determination of larvicidal and phytochemical properties of Callistemon rigidus leaf extracts against Anopheles gambiae, Aedes aegypti and Culex quinquefasciatus. Methods: The standard protocol of WHO was used for larval tests. Twenty five IV instar larvae were exposed to various concentrations from 125-1000 ppm for methanol crude extract (MCE, hexane (HF, chloroform (CF, ethyl acetate (EAF and methanol (MF fractions, from 250-2000 ppm for aqueous extract (AE and 2500 ppm for Diclorvos. The mortality was observed 24 h post-exposure. The LC50 and LC90 values were determined by Probit analysis. Results: The phytochemical analysis revealed that the presence of alkaloids, steroids, saponins, terpenoids, tannins and phenolic compounds, lipids, fats and fixed oils in MCE; terpenoids, steroids, lipids, fats and fixed oils in HF; terpenoids in CF; tannins and phenolic compounds in EAF and alkaloids, tannins, saponins and phenolic compounds in MF. Against Ae. aegypti, HF was the most active fraction with LC50 of 56.25 ppm. Against An. gambiae, HF demonstrated its potential mosquito larvicide killing relatively all exposed larvae at all concentrations with LC50 of 17.11 ppm. Against Cx. quinquefasciatus, only MCE and HF exhibited larvicidal activity with LC50 of 447.38 and 721.95 ppm, respectively. Interpretation & conclusion: Callistemon rigidus exhibited some promising larvicidal activity against medically important vector mosquitoes. Studies are indicated to identify the active compounds from this plant for developing mosquito larvicides

  9. An orbivirus of mosquitoes which induces CO2 sensitivity in mosquitoes and is lethal for rabbits.

    OpenAIRE

    Vazeille, M C; Rosen, L.; Guillon, J C

    1988-01-01

    An orbivirus, JKT-7400, isolated from Culex mosquitoes in Indonesia, replicated to a high titer and induced cytopathic effects in Aedes albopictus cell cultures. The virus produced lethal sensitivity to carbon dioxide in Culex and Aedes mosquitoes as well as in Drosophila melanogaster fruit flies but was not the agent of the hereditary sensitivity to carbon dioxide previously described for Culex quinquefasciatus. When injected intravenously in high doses, JKT-7400 virus was lethal for rabbits...

  10. Periodic dynamic systems for infected hosts and mosquitoes Sistemas dinâmicos periódicos para hospedeiros e mosquitos infectados

    Directory of Open Access Journals (Sweden)

    W. M. Oliva

    1996-06-01

    Full Text Available A mathematical model for the purpose of analysing the dynamic of the populations of infected hosts anf infected mosquitoes when the populations of mosquitoes are periodic in time is here presented. By the computation of a parameter lambda (the spectral radius of a certain monodromy matrix one can state that either the infection peters out naturally (lambda 1 the infection becomes endemic. The model generalizes previous models for malaria by considering the case of periodic coefficients; it is also a variation of that for gonorrhea. The main motivation for the consideration of this present model was the recent studies on mosquitoes at an experimental rice irrigation system, in the South-Eastern region of Brazil.Desenvolveu-se um modelo matemático para analisar a dinâmica das populações de indivíduos e mosquitos infectados quando as populações de mosquitos são periódicas no tempo. Pela determinação de um parâmetro lambda (o raio espectral de uma matriz de monodromia pode-se estabelecer que a infecção termina naturalmente (lambda 1 que a infecção torna-se endêmica. O modelo generaliza, para o caso de coeficientes periódicos, modelos anteriores para malária; como também é uma variação de modelo para a gonorréia. A principal motivação para a consideração do modelo proposto foram os recentes estudos sobre mosquitos numa estação experimental de arroz irrigado, na região Sudeste do Brasil.

  11. Why humans are attractive to malaria mosquitoes

    OpenAIRE

    Smallegange, R. C.; Qiu, Y.T.; Galimard, A.M.S.; Posthumus, M A; van Beek, T. A.; Loon, J.A., van; Takken, W.

    2003-01-01

    Malaria mosquitoes use host odours to find their blood sources, but little is known about the semiochemicals that mediate this behaviour. A combined study is undertaken to identify the volatile human-specific compounds that are used in the host-seeking behaviour of the females of Anopheles gambiae

  12. Musings on Sketches, Artists, and Mosquito Nets

    Centers for Disease Control (CDC) Podcasts

    2014-09-23

    Byron Breedlove reads his essay Musings on Sketches, Artists, and Mosquito Nets about the art of James Whistler and the transmission of vector borne diseases.  Created: 9/23/2014 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 10/20/2014.

  13. Influence of trap construction on mosquito capture.

    Czech Academy of Sciences Publication Activity Database

    Šebesta, Old?ich; Peško, Juraj; Gelbi?, Ivan

    2012-01-01

    Ro?. 6, ?. 2 (2012), s. 209-215. ISSN 1934-7391 R&D Projects: GA MŠk 2B08003 Institutional research plan: CEZ:AV0Z50070508 Institutional support: RVO:68081766 ; RVO:60077344 Keywords : CDC miniature light traps * baited lard-can traps * mosquitoes Subject RIV: EG - Zoology

  14. PARTICULARS IN KILLING GAS PRODUCTION WELLS

    Directory of Open Access Journals (Sweden)

    Davorin Matanovi?

    1994-12-01

    Full Text Available To kill a production well means to perform some technical and technological processes for establishing the static hydraulic balance in the well with no additional surface pressures. The standard procedure of the well killing process as adopted in Croatia, is described. Further, the procedures of how to locate the spot where there is a leakage on production equipment and how to determine the levcl of fluid in tubing or an-nulus is explained. Finally, the aim of this paper is also to point out the importance in selection of killing fluids considering a possibility of formation damage.

  15. [Killing of cattle via electrical stunning].

    Science.gov (United States)

    Maurer, B; Forster, S

    2007-04-01

    For disease control in the case of epidemics killing of cattle via electrical stunning is a method of choice. The official veterinarian is responsible for monitoring the adhesion to animal welfare principles during electrical stunning and killing. This requires specialised knowledge and experience as the symptoms of effective stunning are quite variable in cattle. Signs of effective and ineffective stunning are described below. In addition to suitable technical equipment, restraint of the animals and correct use of the equipment, neurophysiological processes have to be considered. Calm handling of the animals avoiding stress is a prerequisite for ensuring animal welfare and minimising pain especially when killing cattle using electrical methods. PMID:17484500

  16. The Killing : Urban topographies of a crime

    DEFF Research Database (Denmark)

    Agger, Gunhild

    2013-01-01

    This article tracks the uncanny locations of The Killing (2007–2012), relating them to place, space and atmosphere, putting bits and pieces from the topographic puzzle together with cues from the symbolic space in order to see how they fit into the overall pattern of Nordic Noir. In The Killing, the abstract level of space and atmosphere meets the concrete level of place, both influencing the notion of location. This meeting, I suggest, has contributed towards the simultaneous domestic and international appeal of The Killing.

  17. Homefucking is Killing Prostitution / Taavi Eelmaa

    Index Scriptorium Estoniae

    Eelmaa, Taavi, 1971-

    2008-01-01

    Mis jääb vaatajale teatrietendusest meelde? Ilmus Kris Moori raamat "Homefucking is Killing Prostitution". Raamat sisaldab tekste ja Erki Lauri fotosid Von Krahli Teatri samanimelisest etendusest, mida kordagi ei mängitud

  18. Male-killing in African butterflies

    Directory of Open Access Journals (Sweden)

    Sami Saeed M. Hassan

    2013-02-01

    Full Text Available Female-biased sex ratios occur in many insect species as a consequence of infection by maternally-inherited male-killing bacterial endosymbionts. In this paper, we revise the research conducted on the phenomenon of male-killing in African nymphalid butterflies, with special focus on the cases of Danaus chrysippus, Acraea encedon and Acraea encedana. The evolution of male-killing in each case was addressed, together with the phylogeny of male-killers that were identified from this group. Moreover, the potential impacts that male-killers might impose on the evolution of their butterfly hosts were thoroughly investigated. In the end of this review, we present a number of unanswered questions to be targeted by future research work on the male-killing in these butterflies.

  19. Killing Spinor Equations from Nonlinear Realisations

    OpenAIRE

    Miemiec, Andre; Schnakenburg, Igor

    2004-01-01

    Starting from a nonlinear realisation of eleven dimensional supergravity based on the group G11, whose generators appear as low level generators of E11, we present a super extended algebra, which leads to a covariant derivative of spinors identical to the Killing spinor equation of this theory. A similar construction leads to the Killing spinor equation of N=1 pure supergravity in ten dimensions.

  20. Cryptococcus neoformans modulates extracellular killing by neutrophils

    Directory of Open Access Journals (Sweden)

    AsfiaQureshi

    2011-09-01

    Full Text Available We recently established a key role for host sphingomyelin synthase (SMS in the regulation of the killing activity of neutrophils against Cryptococcus neoformans. In this work, we studied the effect of C. neoformans on the killing activity of neutrophils and whether SMS would still be a player against C. neoformans in immunocompromised mice lacking T and NK cells (Tg?26 mice. To this end, we analyzed whether C. neoformans would have any effect on neutrophil survival and killing in vitro and in vivo. We show that unlike C. albicans, neither the presence nor the capsule size of C. neoformans cells have any effect on neutrophil viability. Interestingly, melanized C. neoformans cells totally abrogated the killing activity of neutrophils. Next, we monitored how exposure of neutrophils to C. neoformans cells would interfere with any further killing activity of the medium and found that pre-incubation with live but not “heat-killed” fungal cells significantly inhibits further killing activity of the medium. We next studied whether activation of SMS at the site of C. neoformans infection is dependent on T and NK cells. Using matrix-assisted laser desorption-ionization (MALDI tissue imaging in infected lung we found that similarly to previous observations in the isogenic wild type CBA/J mice, SM 16:0 levels are significantly elevated at the site of infection in mice lacking T and NK cells but only at early time points. This study highlights that C. neoformans may negatively regulate the killing activity of neutrophils and that SMS activation in neutrophils appears to be partially independent of T and/or NK cells.

  1. Dirac operators and Killing spinors with torsion

    International Nuclear Information System (INIS)

    On a Riemannian spin manifold with parallel skew torsion, we use the twistor operator to obtain an eigenvalue estimate for the Dirac operator with torsion. We consider the equality case in dimensions four and six. In odd dimensions we describe Sasaki manifolds on which equality in the estimate is realized by Killing spinors with torsion. In dimension five we characterize all Killing spinors with torsion and obtain certain naturally reductive spaces as exceptional cases.

  2. Law of Policy of Targeted Killing

    OpenAIRE

    Blum, Gabriella; Heymann, Philip B.

    2010-01-01

    This is a chapter from our forthcoming book, 'Laws, Outlaws, and Terrorists: Lessons from the War on Terrorism', (MIT Press, September 2010). This chapter addresses the legal, ethical, and strategic aspects of targeted killings as a counterterrorism measure, drawing on the American and Israeli experience. We argue that since terrorism is neither a traditional war nor a traditional crime, its non-traditional nature must affect how, where, and when we employ targeted killings. Specifically, we ...

  3. Accounting for killing: accountability for death

    OpenAIRE

    SARGIACOMO, MASSIMO; SERVALLI, STEFANIA; Carnegie, Garry D.

    2012-01-01

    Accounting and the conscious secretive killing of humans are rarely concurrently examined in the contemporary and historical literature. Based on examinations of a rare and formerly highly secretive surviving written record found in the Venice State Archive, and other surviving primary records, as well as secondary sources, this novel study outlines evidence of “accounting for killing” of the enemies of the Venetian State during the sixteenth century as a means of rendering the individuals wh...

  4. Predictors of mosquito net use in Ghana

    Directory of Open Access Journals (Sweden)

    Baume Carol A

    2011-09-01

    Full Text Available Abstract Background During the past decade the malaria control community has been successful in dramatically increasing the number of households that own mosquito nets. However, as many as half of nets already in households go unused. This study examines the factors associated with use of nets owned in Ghana. Methods The data come from an August 2008 survey in Ghana of households with a pregnant woman or a guardian of a child under five, conducted during the rainy season. 1796 households were included in this analysis, which generated a sample of 1,852 mosquito nets. Using each net owned as the unit of analysis, multivariate logistic regression was used to examine the relationship of net used last night with 23 potentially explanatory variables having to do with characteristics of the household, of the respondent, and of the net. Odds Ratios, p-values, and confidence intervals were calculated for each variable to develop an explanatory model. Results The final multivariate model consisted of 10 variables statistically associated with whether or not the net was used the prior night: rural location, lower SES, not using coils for mosquito control, fewer nets in the household, newer nets and those in better condition, light blue colour, higher level of education of the guardian of the child under five, knowing that mosquitoes transmit malaria, and paying for the net instead of obtaining it free of charge. Conclusions The results of this study suggest that net use would increase in Ghana if coloured nets were made available in mass distributions as well as in the commercial market; if programmes emphasize that malaria is caused only by night-biting mosquitoes, and that nets protect against mosquitoes better than coils and need to be used even if coils are burning; if donated nets are replaced more frequently so that households have nets that are in good condition; and if there were support for the commercial market so that those who can afford to purchase a net and want to choose their own nets can do so.

  5. Isolation and characterization of larvicidal components against mosquito larvae (Aedes aegypti Linn. from calodendrum capense Thunb

    Directory of Open Access Journals (Sweden)

    A.K. Kiprop

    2005-06-01

    Full Text Available Chromatographic analysis of air-dried root barks and seeds of Calodendrum capense Thunb led to the isolation of calodendrolide (1, limonin (2 and limonin diosphenol (3 whose structures were elucidated using physical and spectroscopic techniques. The compounds and the crude extract were then tested against mosquito 2nd instar larvae of the species Aedes aegypti Linn senso stricto, a yellow fever vector at concentrations of 25, 50, 75, and 100 ppm. Calodendrolide (1 was the most toxic as it killed all the larvae even at the lower concentration of 25 ppm. In addition, concentrations of 15, 10, 5 and 1 ppm of this compound retained moderate efficacy. Calodendrolide (1, C. capense root bark crude, limonin (2, and limonin diosphenol (3 had LC50 values of 13.1, 29.2, 71.6 and 217.1 ppm, respectively.

  6. Rift Valley Fever Virus (RVFv Dissemination inside Mosquitoes and Investigation of the Influence of Climate on Mosquitoes Abundance

    Directory of Open Access Journals (Sweden)

    Rania Ali El Hadi Mohamed

    2013-10-01

    Full Text Available One year surveys were conducted at two sites in Khartoum State capital of Sudan: Hellat Kuku and Soba West. The study was focused into two species of mosquitoes: Aedes vexans and Culex quinquefasciatus. This selection was based on previous investigations indicated their being positive for RVF. The study aimed to investigate on RVFv dissemination inside two species mosquitoes in Khartoum State (Sudan and investigation of the influence of climate on mosquitoes abundance. Weekly aspiration of wild mosquitoes has been conducted during 1st July 2011- 1st July 2012. The collected mosquitoes were identified by using classical keys. Data of climate were obtained from Sudan Meteorology Authorities. Males and females of the two mosquitoes species were divided into three cohorts: salivary glands, abdomen, and wings and legs. RVF Virus was therefore examined into twelve pools using Real- Time PCR technique. Results showed that Temperature, precipitation, and RH were significantly associated with the number of aspirated mosquitoes. The virus has been detected inside the pools of the abdomen and salivary glands of Ae. vexans mosquitoes. However, pools of salivary glands of Cx. quinquefasciatus were negative of the virus in spite of dissemination of the virus in the wings and legs. Based on these results it can be concluded that climatic factors affected on the number of aspirated mosquitoes during the study period. Ae. vexans mosquitoes exhibited an indicator of being competent to transmit the virus in contrast to Cx. quinquefasciatus.

  7. Is drought helping or killing dengue? Investigation of spatiotemporal relationship between dengue fever and drought

    Science.gov (United States)

    Lee, Chieh-Han; Yu, Hwa-Lung

    2015-04-01

    Dengue Fever is a vector-borne disease that is transmitted between human and mosquitos in tropical and sub-tropical regions. Previous studies have found significant relationship between the epidemic of dengue cases and climate variables, especially temperature and precipitation. Besides, the natural phenomena (e.g., drought) are considered that significantly drop the number of dengue cases by killing vector's breeding environment. However, in Kaohsiung City, Taiwan, there are evidences that the temporal pattern of dengue is correlated to drought events. Kaohsiung City experienced two main dengue outbreaks in 2002 and 2014 that both years were confirmed with serious drought. Especially in 2014, Kaohsiung City was suffered from extremely dengue outbreak in 2014 that reported the highest number of dengue cases in the history. This study constructs the spatiotemporal model of dengue incidences and index of drought events (Standardized Precipitation Index, SPI) based on the distributed lag nonlinear model (DLNM). Other meteorological measures are also included in the analysis.

  8. Screening of selected ethnomedicinal plants from South Africa for larvicidal activity against the mosquito Anopheles arabiensis

    Directory of Open Access Journals (Sweden)

    Maharaj Rajendra

    2012-09-01

    Full Text Available Abstract Background This study was initiated to establish whether any South African ethnomedicinal plants (indigenous or exotic, that have been reported to be used traditionally to repel or kill mosquitoes, exhibit effective mosquito larvicidal properties. Methods Extracts of a selection of plant taxa sourced in South Africa were tested for larvicidal properties in an applicable assay. Thirty 3rd instar Anopheles arabiensis larvae were exposed to various extract types (dichloromethane, dichloromethane/methanol (1:1, methanol and purified water of each species investigated. Mortality was evaluated relative to the positive control Temephos (Mostop; Agrivo, an effective emulsifiable concentrate larvicide. Results Preliminary screening of crude extracts revealed substantial variation in toxicity with 24 of the 381 samples displaying 100% larval mortality within the seven day exposure period. Four of the high activity plants were selected and subjected to bioassay guided fractionation. The results of the testing of the fractions generated identified one fraction of the plant, Toddalia asiatica as being very potent against the An. arabiensis larvae. Conclusion The present study has successfully identified a plant with superior larvicidal activity at both the crude and semi pure fractions generated through bio-assay guided fractionation. These results have initiated further research into isolating the active compound and developing a malaria vector control tool.

  9. Acute larvicidal activity against mosquitoes and oxygen consumption inhibitory activity of dihydroguaiaretic acid derivatives.

    Science.gov (United States)

    Nishiwaki, Hisashi; Tabara, Yoshimi; Kishida, Taro; Nishi, Kosuke; Shuto, Yoshihiro; Sugahara, Takuya; Yamauchi, Satoshi

    2015-03-11

    (-)-Dihydroguaiaretic acid (DGA) and its derivatives having 3-hydroxyphenyl (3-OH-DGA) and variously substituted phenyl groups instead of 3-hydroxy-4-methoxyphenyl groups were synthesized to measure their larvicidal activity against the mosquito Culex pipiens Linnaeus, 1758 (Diptera: Culicidae). Compared with DGA and 3-OH-DGA (LC50 (M), 3.52 × 10(-5) and 4.57 × 10(-5), respectively), (8R,8'R)-lignan-3-ol (3) and its 3-Me (10), 2-OH (12), 3-OH (13), and 2-OMe (15) derivatives showed low potency (ca. 6-8 × 10(-5) M). The 4-Me derivative (11) showed the lowest potency (12.1 × 10(-5) M), and the 2-F derivative (4) showed the highest (2.01 × 10(-5) M). All of the synthesized compounds induced an acute toxic symptom against mosquito larvae, with potency varying with the type and position of the substituents. The 4-F derivative (6), which killed larvae almost completely within 45 min, suppressed the O2 consumption of the mitochondrial fraction, demonstrating that this compound inhibited mitochondrial O2 consumption contributing to a respiratory inhibitory activity. PMID:25669766

  10. Infection of the malaria mosquito, Anopheles gambiae, with two species of entomopathogenic fungi: effects of concentration, co-formulation, exposure time and persistence

    Directory of Open Access Journals (Sweden)

    Lwetoijera Dickson W

    2009-12-01

    Full Text Available Abstract Background Entomopathogenic fungi Metarhizium anisopliae and Beauveria bassiana isolates have been shown to infect and reduce the survival of mosquito vectors. Methods Here four different bioassays were conducted to study the effect of conidia concentration, co-formulation, exposure time and persistence of the isolates M. anisopliae ICIPE-30 and B. bassiana I93-925 on infection and survival rates of female Anopheles gambiae sensu stricto. Test concentrations and exposure times ranged between 1 × 107 - 4 × 1010 conidia m-2 and 15 min - 6 h. In co-formulations, 2 × 1010 conidia m-2 of both fungus isolates were mixed at ratios of 4:1, 2:1, 1:1,1:0, 0:1, 1:2 and 1:4. To determine persistence, mosquitoes were exposed to surfaces treated 1, 14 or 28 d previously, with conidia concentrations of 2 × 109, 2 × 1010 or 4 × 1010. Results Mosquito survival varied with conidia concentration; 2 × 1010 conidia m-2 was the concentration above which no further reductions in survival were detectable for both isolates of fungus. The survival of mosquitoes exposed to single and co-formulated treatments was similar and no synergistic or additive effects were observed. Mosquitoes were infected within 30 min and longer exposure times did not result in a more rapid killing effect. Fifteen min exposure still achieved considerable mortality rates (100% mortality by 14 d of mosquitoes, but at lower speed than with 30 min exposure (100% mortality by 9 d. Conidia remained infective up to 28 d post-application but higher concentrations did not increase persistence. Conclusion Both fungus isolates are effective and persistent at low concentrations and short exposure times.

  11. Arctic Health Research Center report no. 101: Combating mosquitoes in arctic Alaska

    US Fish and Wildlife Service, Department of the Interior — This report covers combating mosquitoes in Arctic Alaska. The physiology and biology of mosquitoes is discussed, followed by techniques to combated mosquitoes.

  12. The cell biology of mosquito vitellogenesis

    Scientific Electronic Library Online (English)

    Alexander S., Raikhel.

    Full Text Available Insect vitellogenesis involves coordinated activities of the fat body and oocytes. We have studied these activities at the cellular level in the mosquito. During each vitellogenic cycle, the fat body undergoes three successive stages: 1) proliferation of biosynthetic organelles, 2) vitellogenin synt [...] hesis, 3) termination of vitellogenin synthesis and degradation of biosynthetic organelles by lysosomes. Analysis with monoclonal antibodies and radiolabelling demonstrated that the mosquito yolk protein consists of two subunits (200-kDa and 65-kDa). Both subunits are glycosylated, their carbohydrate moieties are composed of high-mannose oligosaccharides. The yolk protein subunits are derived from a single 220 kDa precursor detected by an in vitro translation. Oocytes become competent to internalize proteins as a result of juvenile hormone-mediated biogenesis of endocytotic organelles. The yolk protein is then accumulated by receptor-mediated endocytosis. A pathway of the yold protein and factors determining its routing in the oocyte have been studied.

  13. Spatial Heterogeneity, Host Movement and Mosquito-Borne Disease Transmission

    OpenAIRE

    Acevedo, Miguel A.; Prosper, Olivia; Lopiano, Kenneth; Ruktanonchai, Nick; Caughlin, T. Trevor; Martcheva, Maia; Osenberg, Craig W.; Smith, David L.

    2015-01-01

    Mosquito-borne diseases are a global health priority disproportionately affecting low-income populations in tropical and sub-tropical countries. These pathogens live in mosquitoes and hosts that interact in spatially heterogeneous environments where hosts move between regions of varying transmission intensity. Although there is increasing interest in the implications of spatial processes for mosquito-borne disease dynamics, most of our understanding derives from models that assume spatially h...

  14. Wolbachia-Associated Bacterial Protection in the Mosquito Aedes aegypti

    OpenAIRE

    Ye, Yixin H; WOOLFIT, MEGAN; Rancès, Edwige; O'Neill, Scott L; McGraw, Elizabeth A

    2013-01-01

    Wolbachia is a commonly occurring bacterium or symbiont that lives inside the cells of insects. Recently, Wolbachia was artificially introduced into the mosquito vector dengue virus that was naturally Wolbachia-free. Wolbachia limits the growth of a range of pathogens transmitted to humans, including viruses, bacteria and parasites inside the mosquito. This “pathogen protection” forms the basis of field trials to determine if releasing Wolbachia into wild mosquito populations could reduce...

  15. Preliminary evaluation of mosquito larvicidal efficacy of plant extracts

    OpenAIRE

    N.G. Das, D. Goswami & B. Rabha

    2007-01-01

    Mosquitoes are the most important single group ofinsects in terms of public health importance, whichtransmit a number of diseases, such as malaria, filariasis,dengue, Japanese encephalitis, etc. causing millionsof deaths every year. Repeated use of syntheticinsecticides for mosquito control has disrupted naturalbiological control systems and led to resurgencesin mosquito populations. It has also resulted in thedevelopment of resistance1, undesirable effects onnon-target organisms and fostered...

  16. Advances in methods for colour marking of mosquitoes

    OpenAIRE

    Verhulst, N.O.; Loonen, J.A.C.M.; Takken, W.

    2013-01-01

    Background: Different techniques are available for colour marking insects and each technique may be suitable for different insect species. Mosquitoes can be marked to determine population size, distribution and flight distance or distinguish closely related species. In this study, two methods of colour marking mosquitoes were described in detail and the impact of both methods on the survival and host-seeking behaviour of the malaria mosquito Anopheles gambiae sensu stricto was investigated. M...

  17. Vector Competence of New Zealand Mosquitoes for Selected Arboviruses

    OpenAIRE

    Kramer, Laura D.; Chin, Pam; Cane, Rachel P.; Kauffman, Elizabeth B.; Mackereth, Graham

    2011-01-01

    New Zealand (NZ) historically has been free of arboviral activity with the exception of Whataroa virus (Togaviridae: Alphavirus), which is established in bird populations and is transmitted by local mosquitoes. This naive situation is threatened by global warming, invasive mosquitoes, and tourism. To determine the threat of selected medically important arboviruses to NZ, vector competence assays were conducted using field collected endemic and introduced mosquito species. Four alphaviruses (T...

  18. Evaluation of botanicals as repellents against mosquitoes

    OpenAIRE

    N G Das, I. Baruah

    2003-01-01

    Repellent properties of three plant extracts—essential oil (steam distillate) of Zanthoxylumlimonella (fruits), Citrus aurantifolia (leaf) and petroleum ether extract of Z. limonella (fruits)were evaluated as repellent against Aedes (S.) albopictus mosquitoes in mustard (Dhara) and coconut(Parachute) oil base under laboratory conditions. Three concentrations—10, 20 and 30% of therepellents were evaluated. Repellents in mustard oil afforded longer protection time against thebites of Aedes ...

  19. Crab Hole Mosquito Bluesâ??The Story

    Centers for Disease Control (CDC) Podcasts

    2011-05-12

    This podcast reports on a humorous song that takes a look at a very serious human and equine disease. Written and performed by the MARU Health Angels Band, Bill Dietz, director of the Division of Nutrition, Physical Activity and Obesity at CDC, talks about the song, "Crab Hole Mosquito Blues", and the history behind it.  Created: 5/12/2011 by National Center for Emerging Zoonotic and Infectious Diseases (NCEZID).   Date Released: 5/23/2011.

  20. Climate change and mosquito-borne disease.

    OpenAIRE

    Reiter, P.

    2001-01-01

    Global atmospheric temperatures are presently in a warming phase that began 250--300 years ago. Speculations on the potential impact of continued warming on human health often focus on mosquito-borne diseases. Elementary models suggest that higher global temperatures will enhance their transmission rates and extend their geographic ranges. However, the histories of three such diseases--malaria, yellow fever, and dengue--reveal that climate has rarely been the principal determinant of their pr...

  1. Forkhead transcription factors regulate mosquito reproduction.

    Science.gov (United States)

    Hansen, Immo A; Sieglaff, Douglas H; Munro, James B; Shiao, Shin-Hong; Cruz, Josefa; Lee, Iris W; Heraty, John M; Raikhel, Alexander S

    2007-09-01

    Forkhead-box (Fox) genes encode a family of transcription factors defined by a 'winged helix' DNA-binding domain. In this study we aimed to identify Fox factors that are expressed within the fat body of the yellow fever mosquito Aedes aegypti, and determine whether any of these are involved in the regulation of mosquito yolk protein gene expression. The Ae. aegypti genome contains 18 loci that encode putative Fox factors. Our stringent cladistic analysis has profound implications for the use of Fox genes as phylogenetic markers. Twelve Ae. aegypti Fox genes are expressed within various tissues of adult females, six of which are expressed within the fat body. All six Fox genes expressed in the fat body displayed dynamic expression profiles following a blood meal. We knocked down the 'fat body Foxes' through RNAi to determine whether these 'knockdowns' hindered amino acid-induced vitellogenin gene expression. We also determined the effect of these knockdowns on the number of eggs deposited following a blood meal. Knockdown of FoxN1, FoxN2, FoxL, and FoxO, had a negative effect on amino acid-induced vitellogenin gene expression and resulted in significantly fewer eggs laid. Our analysis stresses the importance of Fox transcription factors in regulating mosquito reproduction. PMID:17681238

  2. Manipulating insulin signaling to enhance mosquito reproduction

    Directory of Open Access Journals (Sweden)

    Rasgon Jason L

    2009-08-01

    Full Text Available Abstract Backgrond In the mosquito Aedes aegypti the insulin/insulin growth factor I signaling (IIS cascade is a key regulator of many physiological processes, including reproduction. Two important reproductive events, steroidogenesis in the ovary and yolk synthesis in the fat body, are regulated by the IIS cascade in mosquitoes. The signaling molecule phosphatase and tensin homolog (PTEN is a key inhibitor of the IIS cascade that helps modulate the activity of the IIS cascade. In Ae. aegypti, six unique splice variants of AaegPTEN were previously identified, but the role of these splice variants, particularly AaegPTEN3 and 6, were unknown. Results Knockdown of AaegPTEN or its specific splice variant AaegPTEN6 (the splice variant thought to regulate reproduction in the ovary and fat body using RNAi led to a 15–63% increase in egg production with no adverse effects on egg viability during the first reproductive cycle. Knockdown of AaegPTEN3, expressed predominantly in the head, had no effect on reproduction. We also characterized the protein expression patterns of these two splice variants during development and in various tissues during a reproductive cycle. Conclusion Previous studies in a range of organisms, including Drosophila melanogaster and Caenorhabditis elegans, have demonstrated that disruption of the IIS cascade leads to decreased reproduction or sterility. In this study we demonstrate that knockdown of the IIS inhibitor PTEN can actually increase reproduction in the mosquito, at least during the first reproductive cycle.

  3. Lista dos mosquitos da Bolívia: (Diptera, Culicidae

    Directory of Open Access Journals (Sweden)

    N. L. Cerqueira

    1943-08-01

    Full Text Available Em quinze gêneros, cento e vinte e seis espécies de mosquitos foram constatadas no material capturado pelo Servicio de Fiebre Amarilla desde 1933 até 1942. Êste número, três vezes mais elevado do que o existente na literatura para o país, seria ainda maior se possível fôsse identificar sem o auxílio de machos inúmeras fêmeas das espécies de Culex. Tôdas as espécies estudadas apresentavam suas distribuições geográficas nos departamentos e províncias onde casos de Febre Amarela foram observados. Algumas cosiderações foram feitas em torno de espécies que não correspondiam exatamente com as descrições existentes, assim como descrições de outras foram dadas, cujos sexos opostos apenas eram conhecidos.One hundred and twenty-six species of mosquitoes, corresponding fifteen genera, have been found in material collected by the Bolivian Yellow Fever Service between 1933 and 1942. This number is three times that given for the country in existing literature and would be even largar if it were possible to identify a consierable group of Culex mosquitoes composed principally of female specimens. All species studied come from Departmetns and Provinces where cases of yellow fever have been found. Consideration has been given to certain species which do not agree exactly with existing descriptions, and supplementary descriptions have been made for the male or female of two additional species for which only description of the opposite sex had existed.

  4. Introduction and control of three invasive mosquito species in the Netherlands, July-October 2010

    OpenAIRE

    Scholte, E.J.; Den Hartog, W; Dik, M; Schoelitsz, B; Brooks, M.; Schaffner, F.; Foussadier, R; Braks, M; Beeuwkes, J.

    2010-01-01

    In July 2010, during routine mosquito surveillance inspections at companies that import used tires, three invasive species were found at five locations in the Netherlands: the yellow fever mosquito (Aedes aegypti), the Asian tiger mosquito (Ae. albopictus), and the American rock-pool mosquito (Ae. atropalpus). This is the first time that Ae. aegypti is reported from the Netherlands. Mosquito control was initiated one week after the first invasive mosquito was found, ...

  5. Venereal Transmission of Chikungunya Virus by Aedes aegypti Mosquitoes (Diptera: Culicidae)

    OpenAIRE

    Mavale, Mangala; Parashar, Deepti; Sudeep, Anakkathil; Gokhale, Mangesh; Ghodke, Youwaraj; Geevarghese, Geevarghese; Arankalle, Vidya; Mishra, Akhilesh Chandra

    2010-01-01

    Experiments were conducted to demonstrate the role of male Aedes aegypti mosquitoes in the maintenance and transmission of chikungunya virus (CHIKV) to female mosquitoes. We demonstrated that infected male mosquitoes are capable of infecting females during mating. The infection rate in female mosquitoes was 11% when virgin female mosquitoes were allowed to coinhabit with infected males. The body suspension of venereally infected female mosquitoes induced illness in infant Swiss albino mice, w...

  6. DsRed2 transient expression in Culex quinquefasciatus mosquitoes

    Scientific Electronic Library Online (English)

    Andre Barretto Bruno, Wilke; Sarah, Scaife; Luke, Alphey; Mauro Toledo, Marrelli.

    2013-06-01

    Full Text Available Culex quinquefasciatus mosquitoes have been successfully genetically modified only once, despite the efforts of several laboratories to transform and establish a stable strain. We have developed a transient gene expression method, in Culex, that delivers plasmid DNA directly to the mosquito haemoly [...] mph and additional tissues. We were able to express DsRed2 fluorescent protein in adult Cx. quinquefasciatus mosquitoes by injecting plasmids directly into their thorax. The expression of DsRed2 in adult Cx. quinquefasciatus mosquitoes is an important stepping stone to genetic transformation and the potential use of new control strategies and genetic interactions.

  7. Potential Use of Mosquito’s Salivary Components as Novel Target for The Development of Transmission Blocking Vaccine (TBV)

    OpenAIRE

    KARTIKA SENJARINI

    2013-01-01

    Mosquito-borne diseases are rampant in most tropical regions of the world, especially rural, forested, and coastal areas such as Indonesia. Despite long-standing chemotherapeutic intercession and vector control programs, mosquito-borne diseases exact a heavy burden on human health in Indonesia. Two major public health problems transmitted by mosquito in Indonesia are malaria and dengue haemorrhagic fever (DHF), causing millions of clinical episodes occurring annu...

  8. Rift Valley Fever Virus (RVFv) Dissemination inside Mosquitoes and Investigation of the Influence of Climate on Mosquitoes Abundance

    OpenAIRE

    Rania Ali El Hadi Mohamed; Emadeldin Hassan Konozy; El Amin El Rayah

    2013-01-01

    One year surveys were conducted at two sites in Khartoum State capital of Sudan: Hellat Kuku and Soba West. The study was focused into two species of mosquitoes: Aedes vexans and Culex quinquefasciatus. This selection was based on previous investigations indicated their being positive for RVF. The study aimed to investigate on RVFv dissemination inside two species mosquitoes in Khartoum State (Sudan) and investigation of the influence of climate on mosquitoes abundance. Weekly aspiration of w...

  9. Genetic Control of Mosquitoes: population suppression strategies Controle genético de mosquitos: estratégias de supressão de populações

    Directory of Open Access Journals (Sweden)

    André Barretto Bruno Wilke

    2012-10-01

    Full Text Available Over the last two decades, morbidity and mortality from malaria and dengue fever among other pathogens are an increasing Public Health problem. The increase in the geographic distribution of vectors is accompanied by the emergence of viruses and diseases in new areas. There are insufficient specific therapeutic drugs available and there are no reliable vaccines for malaria or dengue, although some progress has been achieved, there is still a long way between its development and actual field use. Most mosquito control measures have failed to achieve their goals, mostly because of the mosquito's great reproductive capacity and genomic flexibility. Chemical control is increasingly restricted due to potential human toxicity, mortality in no target organisms, insecticide resistance, and other environmental impacts. Other strategies for mosquito control are desperately needed. The Sterile Insect Technique (SIT is a species-specific and environmentally benign method for insect population suppression, it is based on mass rearing, radiation mediated sterilization, and release of a large number of male insects. Releasing of Insects carrying a dominant lethal gene (RIDL offers a solution to many of the drawbacks of traditional SIT that have limited its application in mosquitoes while maintaining its environmentally friendly and species-specific utility. The self-limiting nature of sterile mosquitoes tends to make the issues related to field use of these somewhat less challenging than for self-spreading systems characteristic of population replacement strategies. They also are closer to field use, so might be appropriate to consider first. The prospect of genetic control methods against mosquito vectored human diseases is rapidly becoming a reality, many decisions will need to be made on a national, regional and international level regarding the biosafety, social, cultural and ethical aspects of the use and deployment of these vector control methods.Ao longo das duas últimas décadas, morbidade e mortalidade da malária e dengue e outros patógenos tem se tornado cada vez mais um problema de Saúde Pública. O aumento na distribuição geográfica de seus respectivos vetores é acompanhada pela emergência de doenças em novas áreas. Não estão disponíveis drogas específicas suficientes e não há vacinas específicas para imunizar as populações alvo. As medidas de controle de mosquitos atuais falharam em atingir os objetivos propostos, principalmente devido à grande capacidade reprodutiva dos mosquitos e alta flexibilidade genômica. O controle químico se torna cada vez mais restrito devido a sua potencial toxicidade aos seres humanos, mortalidade de organismos não alvos, resistência a inseticida além de outros impactos ambientais. Novas estratégias de controle são necessárias. A técnica do inseto estéril (SIT é um método de supressão populacional espécie específico e ambientalmente amigável, baseia-se na criação em massa, esterilização mediante irradiação e liberação de um grande número de insetos machos. Liberar insetos carregando um gene letal dominante (RIDL oferece uma solução a muitas limitações impostas pela técnica do inseto estéril (SIT que limitaram sua aplicação em mosquitos e ainda assim mantém suas características de ambientalmente amigável e espécie específica. A natureza auto-limitante de mosquitos estéreis tende a deixar alguns empecilhos para uso no campo, de certa forma, menos desafiadores quando comparados a sistemas auto-propagação, característicos de estratégias de substituição de população. Sistemas auto-limitantes estão mais próximos para uso no campo, portanto pode ser apropriado considerá-lo primeiro. A perspectiva de métodos de controle genéticos contra mosquitos vetores de doenças que acometem humanos está rapidamente se tornando uma realidade, muitas decisões terão de ser tomadas em âmbito nacional, regional e internacional com relação a aspectos étnicos, sociais, culturais e de biossegurança para o uso e liberação

  10. Genetic Control of Mosquitoes: population suppression strategies / Controle genético de mosquitos: estratégias de supressão de populações

    Scientific Electronic Library Online (English)

    André Barretto Bruno, Wilke; Mauro Toledo, Marrelli.

    2012-10-01

    Full Text Available Ao longo das duas últimas décadas, morbidade e mortalidade da malária e dengue e outros patógenos tem se tornado cada vez mais um problema de Saúde Pública. O aumento na distribuição geográfica de seus respectivos vetores é acompanhada pela emergência de doenças em novas áreas. Não estão disponíveis [...] drogas específicas suficientes e não há vacinas específicas para imunizar as populações alvo. As medidas de controle de mosquitos atuais falharam em atingir os objetivos propostos, principalmente devido à grande capacidade reprodutiva dos mosquitos e alta flexibilidade genômica. O controle químico se torna cada vez mais restrito devido a sua potencial toxicidade aos seres humanos, mortalidade de organismos não alvos, resistência a inseticida além de outros impactos ambientais. Novas estratégias de controle são necessárias. A técnica do inseto estéril (SIT) é um método de supressão populacional espécie específico e ambientalmente amigável, baseia-se na criação em massa, esterilização mediante irradiação e liberação de um grande número de insetos machos. Liberar insetos carregando um gene letal dominante (RIDL) oferece uma solução a muitas limitações impostas pela técnica do inseto estéril (SIT) que limitaram sua aplicação em mosquitos e ainda assim mantém suas características de ambientalmente amigável e espécie específica. A natureza auto-limitante de mosquitos estéreis tende a deixar alguns empecilhos para uso no campo, de certa forma, menos desafiadores quando comparados a sistemas auto-propagação, característicos de estratégias de substituição de população. Sistemas auto-limitantes estão mais próximos para uso no campo, portanto pode ser apropriado considerá-lo primeiro. A perspectiva de métodos de controle genéticos contra mosquitos vetores de doenças que acometem humanos está rapidamente se tornando uma realidade, muitas decisões terão de ser tomadas em âmbito nacional, regional e internacional com relação a aspectos étnicos, sociais, culturais e de biossegurança para o uso e liberação destes métodos de controle de vetores. Abstract in english Over the last two decades, morbidity and mortality from malaria and dengue fever among other pathogens are an increasing Public Health problem. The increase in the geographic distribution of vectors is accompanied by the emergence of viruses and diseases in new areas. There are insufficient specific [...] therapeutic drugs available and there are no reliable vaccines for malaria or dengue, although some progress has been achieved, there is still a long way between its development and actual field use. Most mosquito control measures have failed to achieve their goals, mostly because of the mosquito's great reproductive capacity and genomic flexibility. Chemical control is increasingly restricted due to potential human toxicity, mortality in no target organisms, insecticide resistance, and other environmental impacts. Other strategies for mosquito control are desperately needed. The Sterile Insect Technique (SIT) is a species-specific and environmentally benign method for insect population suppression, it is based on mass rearing, radiation mediated sterilization, and release of a large number of male insects. Releasing of Insects carrying a dominant lethal gene (RIDL) offers a solution to many of the drawbacks of traditional SIT that have limited its application in mosquitoes while maintaining its environmentally friendly and species-specific utility. The self-limiting nature of sterile mosquitoes tends to make the issues related to field use of these somewhat less challenging than for self-spreading systems characteristic of population replacement strategies. They also are closer to field use, so might be appropriate to consider first. The prospect of genetic control methods against mosquito vectored human diseases is rapidly becoming a reality, many decisions will need to be made on a national, regional and international level regarding the biosafety, social, cultural a

  11. Honor Killing in Pakistan: An Islamic Perspective

    OpenAIRE

    Niaz Muhammad; Mufti. Muhammad Mushtaq Ahmed; Abdullah Abdullah; Fazle Omer; Naqeeb Hussain Shah

    2012-01-01

    Islamic Republic of Pakistan is considered as one of the most dangerous and unsafe country for women in the world, because of the increasing rate of crimes against women in the shape of honor killing and honor related violence. Which are known as assaults committed against women for what is considered immoral behavior. Some researchers and Islamic scholars links act of honor killing with Islam, they tried to justify this crime with some general sayings of Prophet Peace be upon him. In this pa...

  12. Cytotoxic Killing and Immune Evasion by Repair

    Science.gov (United States)

    Chan, Cliburn; George, Andrew J. T.; Stark, Jaroslav

    2007-07-01

    The interaction between the immune system and pathogens is a complex one, with pathogens constantly developing new ways of evading destruction by the immune system. The immune system's task is made even harder when the pathogen in question is an intra-cellular one (such as a virus or certain bacteria) and it is necessary to kill the infected host cell in order to eliminate the pathogen. This causes damage to the host, and such killing therefore needs to be carefully controlled, particularly in tissues with poor regenerative potential, or those involved in the immune response itself. Host cells therefore possess repair mechanisms which can counteract killing by immune cells. These in turn can be subverted by pathogens which up-regulate the resistance of infected cells to killing. In this paper, we explore the hypothesis that this repair process plays an important role in determining the efficacy of evasion and escape from immune control. We model a situation where cytotoxic T lymphocytes (CTL) and natural killer (NK) cells kill pathogen-infected and tumour cells by directed secretion of preformed granules containing perforin and granzymes. Resistance to such killing can be conferred by the expression of serine protease inhibitors (serpins). These are utilized by several virally infected and tumour cells, as well as playing a role in the protection of host bystander, immune and immuneprivileged cells. We build a simple stochastic model of cytotoxic killing, where serpins can neutralize granzymes stoichiometrically by forming an irreversible complex, and the survival of the cell is determined by the balance between serpin depletion and replenishment, which in its simplest form is equivalent to the well known shot noise process. We use existing analytical results for this process, and additional simulations to analyse the effects of repair on cytotoxic killing. We then extend the model to the case of a replicating target cell population, which gives a branching process coupled to shot noise. We show how the process of repair can have a major impact on the dynamics of pathogen evasion and escape of tumour cells from immune surveillance

  13. Mothers who killed or attempted to kill their child: life circumstances, childhood abuse, and types of killing.

    Science.gov (United States)

    Haapasalo, J; Petäjä, S

    1999-01-01

    The objectives of the present study were to examine the life circumstances, childhood abuse, and types of homicidal acts of 48 mothers who killed/attempted to kill their child(ren) under age 12 between 1970-96 in Finland. Data on the mothers'life stresses, psychological problems, and childhood abuse were collected from mental state examination (MSE) reports. The cases were divided into 15 neonaticides and 33 mothers who killed an older child. Childhood abuse was documented in 63% of the mothers' MSE reports. Qualitative analysis identified neonaticides,joint homicide-suicide attempts, impulsive aggression, psychotic acts, postpartum depression, and abusive acts. Nonlinear principal components analysis showed that different variables were related to the neonaticide and non-neonaticide cases. We concluded that despite differences in the psychosocial profiles of neonaticides and other maternal homicidal acts the cycle of violence perspective can be applied to both cases, even though it may not be a sufficient explanation for maternal child killings. PMID:10606431

  14. MOSQUITO MAGNETS AS BARRIER TREATMENTS AGAINST SALT MARSH MOSQUITOES AROUND RESIDENTIAL HOUSES IN MARSH AREA

    Science.gov (United States)

    In recent years, more residential homes have been built around the marsh areas located on the Intra-Coastal Waterway (ICW) and brought more complaints about marsh mosquitoes. Many homeowner associations have created policies and regulations that forbid the spraying of pesticides. The new challenge h...

  15. ATTRACTION OF CULEX MOSQUITOES TO COMPOUNDS IDENTIFIED FROM BIRDS

    Science.gov (United States)

    Although birds play a critical role in the maintenance and amplification of mosquito populations and as reservoirs of disease, little is known about the cues used by mosquitoes to locate birds. Most attractants for traps have been developed for anthropophilic species such as Aedes aegypti using cue...

  16. Isolation and Molecular Characterization of Banna Virus from Mosquitoes, Vietnam

    OpenAIRE

    Nabeshima, Takeshi; Nga, Phan Thi; Guillermo, Posadas; Del Carmen Parquet, Maria; Yu, Fuxun; Thuy, Nguyen Thanh; Trang, Bui Minh; Hien, Nguyen Tran; Nam, Vu Sinh; Inoue, Shingo; Hasebe, Futoshi; Morita, Kouichi

    2008-01-01

    We isolated and characterized a Banna virus from mosquitoes in Vietnam; 5 strains were isolated from field-caught mosquitoes at various locations; Banna virus was previously isolated from encephalitis patients in Yunnan, China, in 1987. Together, these findings suggest widespread distribution of this virus throughout Southeast Asia.

  17. Crowdsourcing for large-scale mosquito (Diptera: Culicidae) sampling

    Science.gov (United States)

    Sampling a cosmopolitan mosquito (Diptera: Culicidae) species throughout its range is logistically challenging and extremely resource intensive. Mosquito control programmes and regional networks operate at the local level and often conduct sampling activities across much of North America. A method f...

  18. NEW TRAPS FOR MOSQUITO POPULATION SURVEILLANCE AND CONTROL

    Science.gov (United States)

    In 1989 there were two basic traps available for mosquito surveillance, the Centers for Disease Control (CDC) and the New Jersey (NJ) light trap. These traps were not considered to be useful for population control. Bug Zappers were the only available device marketed for mosquito control. Since 1...

  19. Aedes aegypti Mosquitoes Imported into the Netherlands, 2010

    OpenAIRE

    BROWN, JULIA E.; Scholte, Ernst-Jan; Dik, Marian; Den Hartog, Wietse; Beeuwkes, Jacob; POWELL, JEFFREY R.

    2011-01-01

    During summer 2010, Aedes aegypti mosquitoes were discovered in the Netherlands. Using genetic markers, we tracked the origin of these mosquitoes to a tire shipment from Miami, Florida, USA. Surveillance of tire exports from the United States should be included as part of a comprehensive surveillance system.

  20. Protocol for RNAi Assays in Adult Mosquitoes (A. gambiae)

    OpenAIRE

    Garver, Lindsey; Dimopoulos, George

    2007-01-01

    Reverse genetic approaches have proven extremely useful for determining which genes underly resistance to vector pathogens in mosquitoes. This video protocol illustrates a method used by the Dimopoulos lab to inject dsRNA into Anopheles gambiae mosquitoes, which harbor the malaria parasite. The technique manipulating the injection setup and injecting dsRNA into the thorax is illustrated.

  1. UV light and urban pollution: Bad cocktail for mosquitoes?

    International Nuclear Information System (INIS)

    Highlights: •Mosquito tolerance to temephos is induced by PAHs and UV exposure. •Toxicity of fluoranthene for mosquito Malpighian tubules cells is induced by UV. •Fluoranthene crystallizes in mosquito Malpighian tubules upon UV exposure. •Mixture of two PAHs is less toxic for mosquitoes than each PAHs separately. •Combination of abiotic parameters (PAHs and UV) affect mosquito physiology. -- Abstract: Mosquito breeding sites consist of water pools, which can either be large open areas or highly covered ponds with vegetation, thus with different light exposures combined with the presence in water of xenobiotics including polycyclic aromatic hydrocarbons (PAHs) generated by urban pollution. UV light and PAHs are abiotic factors known to both affect the mosquito insecticide resistance status. Nonetheless, their potential combined effects on the mosquito physiology have never been investigated. The present article aims at describing the effects of UV exposure alongside water contamination with two major PAH pollutants (fluoranthene and benzo[a]pyrene) on a laboratory population of the yellow fever mosquito Aedes aegypti. To evaluate the effects of PAH exposure and low energetic UV (UV-A) irradiation on mosquitoes, different parameters were measured including: (1) The PAH localization and its impact on cell mortality by fluorescent microscopy; (2) The detoxification capacities (cytochrome P450, glutathione-S-transferase, esterase); (3) The responses to oxidative stress (Reactive Oxygen Species–ROS) and (4) The tolerance of mosquito larvae to a bioinsecticide (Bacillus thuringiensis subsp. israelensis–Bti) and to five chemical insecticides (DDT, imidacloprid, permethrin, propoxur and temephos). Contrasting effects regarding mosquito cell mortality, detoxification and oxidative stress were observed as being dependent on the pollutant considered, despite the fact that the two PAHs belong to the same family. Moreover, UV is able to modify pollutant effects on mosquitoes, including tolerance to three insecticides (imidacloprid, propoxur and temephos), cell damage and response to oxidative stress. Taken together, our results suggest that UV and pollution, individually or in combination, are abiotic parameters that can affect the physiology and insecticide tolerance of mosquitoes; but the complexity of their direct effect and of their interaction will require further investigation to know in which condition they can affect the efficacy of insecticide-based vector control strategies in the field

  2. UV light and urban pollution: Bad cocktail for mosquitoes?

    Energy Technology Data Exchange (ETDEWEB)

    Tetreau, Guillaume, E-mail: guillaume.tetreau@gmail.com [Laboratoire d’Ecologie Alpine, LECA-UMR 5553, Université de Grenoble 1, BP 53, 38041 Grenoble cedex 09 (France); Department of Entomology, Cornell University, New York State Agricultural Experiment Station, Geneva, NY 14456 (United States); Chandor-Proust, Alexia; Faucon, Frédéric; Stalinski, Renaud; Akhouayri, Idir; Prud’homme, Sophie M.; Régent-Kloeckner, Myriam; Raveton, Muriel; Reynaud, Stéphane [Laboratoire d’Ecologie Alpine, LECA-UMR 5553, Université de Grenoble 1, BP 53, 38041 Grenoble cedex 09 (France)

    2014-01-15

    Highlights: •Mosquito tolerance to temephos is induced by PAHs and UV exposure. •Toxicity of fluoranthene for mosquito Malpighian tubules cells is induced by UV. •Fluoranthene crystallizes in mosquito Malpighian tubules upon UV exposure. •Mixture of two PAHs is less toxic for mosquitoes than each PAHs separately. •Combination of abiotic parameters (PAHs and UV) affect mosquito physiology. -- Abstract: Mosquito breeding sites consist of water pools, which can either be large open areas or highly covered ponds with vegetation, thus with different light exposures combined with the presence in water of xenobiotics including polycyclic aromatic hydrocarbons (PAHs) generated by urban pollution. UV light and PAHs are abiotic factors known to both affect the mosquito insecticide resistance status. Nonetheless, their potential combined effects on the mosquito physiology have never been investigated. The present article aims at describing the effects of UV exposure alongside water contamination with two major PAH pollutants (fluoranthene and benzo[a]pyrene) on a laboratory population of the yellow fever mosquito Aedes aegypti. To evaluate the effects of PAH exposure and low energetic UV (UV-A) irradiation on mosquitoes, different parameters were measured including: (1) The PAH localization and its impact on cell mortality by fluorescent microscopy; (2) The detoxification capacities (cytochrome P450, glutathione-S-transferase, esterase); (3) The responses to oxidative stress (Reactive Oxygen Species–ROS) and (4) The tolerance of mosquito larvae to a bioinsecticide (Bacillus thuringiensis subsp. israelensis–Bti) and to five chemical insecticides (DDT, imidacloprid, permethrin, propoxur and temephos). Contrasting effects regarding mosquito cell mortality, detoxification and oxidative stress were observed as being dependent on the pollutant considered, despite the fact that the two PAHs belong to the same family. Moreover, UV is able to modify pollutant effects on mosquitoes, including tolerance to three insecticides (imidacloprid, propoxur and temephos), cell damage and response to oxidative stress. Taken together, our results suggest that UV and pollution, individually or in combination, are abiotic parameters that can affect the physiology and insecticide tolerance of mosquitoes; but the complexity of their direct effect and of their interaction will require further investigation to know in which condition they can affect the efficacy of insecticide-based vector control strategies in the field.

  3. Control of mosquitoes by the sterile male technique

    International Nuclear Information System (INIS)

    Field tests on the applicability of SIT to mosquito control have been conducted since the late 1950s. Early field experiments were conducted by releasing radiation-sterilized males. Methods of chemically sterilizing mosquitoes were also developed. Genetically altered strains which are partially sterile were also developed, studied and then used in field experiments. The earliest release experiments with mosquitoes were unsuccessful in introducing sterility into natural populations or reducing insect density, but identified problems and developed methodology. A summary of the releases conducted since the 1950s is given as background and then recent tests are reviewed in more detail where population control was achieved. The advances made in understanding the dynamics of field populations of mosquitoes when subjected to SIT are also reviewed. The problems associated with SIT for mosquito control - absolute density, growth rate, migration and others - are also discussed. (author)

  4. Mosquito transmission of the rodent malaria parasite Plasmodium chabaudi

    Directory of Open Access Journals (Sweden)

    Spence Philip J

    2012-12-01

    Full Text Available Abstract Background Serial blood passage of Plasmodium increases virulence, whilst mosquito transmission inherently regulates parasite virulence within the mammalian host. It is, therefore, imperative that all aspects of experimental malaria research are studied in the context of the complete Plasmodium life cycle. Methods Plasmodium chabaudi chabaudi displays many characteristics associated with human Plasmodium infection of natural mosquito vectors and the mammalian host, and thus provides a unique opportunity to study the pathogenesis of malaria in a single infection setting. An optimized protocol that permits efficient and reproducible vector transmission of P. c. chabaudi via Anopheles stephensi was developed. Results and conclusions This protocol was utilized for mosquito transmission of genetically distinct P. c. chabaudi isolates, highlighting differential parasite virulence within the mosquito vector and the spectrum of host susceptibility to infection initiated via the natural route, mosquito bite. An apposite experimental system in which to delineate the pathogenesis of malaria is described in detail.

  5. How Mosquitoes Can Fly in the Rain

    Science.gov (United States)

    MIT BLOSSOMS

    2012-10-29

    In this lesson, we learn how insects can fly in the rain. The objective is to calculate the impact forces of raindrops on flying mosquitoes. Students will gain experience with using Newton's laws, gathering data from videos and graphs, and most importantly, the utility of making approximations. No calculus will be used in this lesson, but familiarity with torque and force balances is suggested. No calculators will be needed, but students should have pencil and paper to make estimations and, if possible, copies of the graphs provided with the lesson. Between lessons, students are recommended to discuss the assignments with their neighbors.

  6. Killing Hitler: A Writer's Journey and Angst.

    Science.gov (United States)

    Thaler, Paul

    2002-01-01

    Describes the author's experiences in preparing a talk that "evokes the specter" of Adolf Hitler and in writing an historical account of a British plot to kill Hitler. Address the question of why the British allowed him to live that final year of the war. Muses on why scholars write, and the impact of violence and terrorism. (SG)

  7. School Shootings; Standards Kill Students and Society

    Science.gov (United States)

    Angert, Betsy L.

    2008-01-01

    School shootings have been in the news of late. People ponder what occurs in classrooms today. Why would a young person wish to take a life? Within educational institutions, the killings are a concern. In our dire attempt to teach the children and ensure student success, it seems many of our offspring are lost. Some students feel separate from…

  8. Cytoplasmic actin is an extracellular insect immune factor which is secreted upon immune challenge and mediates phagocytosis and direct killing of bacteria, and is a Plasmodium Antagonist.

    Science.gov (United States)

    Sandiford, Simone L; Dong, Yuemei; Pike, Andrew; Blumberg, Benjamin J; Bahia, Ana C; Dimopoulos, George

    2015-02-01

    Actin is a highly versatile, abundant, and conserved protein, with functions in a variety of intracellular processes. Here, we describe a novel role for insect cytoplasmic actin as an extracellular pathogen recognition factor that mediates antibacterial defense. Insect actins are secreted from cells upon immune challenge through an exosome-independent pathway. Anopheles gambiae actin interacts with the extracellular MD2-like immune factor AgMDL1, and binds to the surfaces of bacteria, mediating their phagocytosis and direct killing. Globular and filamentous actins display distinct functions as extracellular immune factors, and mosquito actin is a Plasmodium infection antagonist. PMID:25658622

  9. Dirac operators and Killing spinors with torsion; Dirac-Operatoren und Killing-Spinoren mit Torsion

    Energy Technology Data Exchange (ETDEWEB)

    Becker-Bender, Julia

    2012-12-17

    On a Riemannian spin manifold with parallel skew torsion, we use the twistor operator to obtain an eigenvalue estimate for the Dirac operator with torsion. We consider the equality case in dimensions four and six. In odd dimensions we describe Sasaki manifolds on which equality in the estimate is realized by Killing spinors with torsion. In dimension five we characterize all Killing spinors with torsion and obtain certain naturally reductive spaces as exceptional cases.

  10. Prevent Tipping Furniture from Injuring or Killing Young Children

    Science.gov (United States)

    Prevent Tipping Furniture from Injuring or Killing Young Children The nation’s emergency physicians handle tragic situations too often, but few things ... a child — killed by a piece of a furniture, appliance or a television falling on them. “It ...

  11. 9 CFR 113.205 - Newcastle Disease Vaccine, Killed Virus.

    Science.gov (United States)

    2010-01-01

    ...false Newcastle Disease Vaccine, Killed Virus. 113.205 Section 113.205 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.205 Newcastle...

  12. 9 CFR 113.201 - Canine Distemper Vaccine, Killed Virus.

    Science.gov (United States)

    2010-01-01

    ...false Canine Distemper Vaccine, Killed Virus. 113.201 Section 113.201 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.201 Canine...

  13. 9 CFR 113.204 - Mink Enteritis Vaccine, Killed Virus.

    Science.gov (United States)

    2010-01-01

    ...false Mink Enteritis Vaccine, Killed Virus. 113.204 Section 113.204 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.204 Mink...

  14. 9 CFR 113.212 - Bursal Disease Vaccine, Killed Virus.

    Science.gov (United States)

    2010-01-01

    ...false Bursal Disease Vaccine, Killed Virus. 113.212 Section 113.212 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.212 Bursal...

  15. 9 CFR 113.206 - Wart Vaccine, Killed Virus.

    Science.gov (United States)

    2010-01-01

    ...2010-01-01 false Wart Vaccine, Killed Virus. 113.206 Section 113.206 Animals...INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS...VECTORS STANDARD REQUIREMENTS Killed Virus Vaccines § 113.206 Wart...

  16. Towards the genetic manipulation of mosquito disease vectors

    International Nuclear Information System (INIS)

    Our research is aimed at developing the technologies necessary to undertake the genetic manipulation of insect vector genomes. In the longer term, we wish to explore the potential that this technology may have for developing novel strategies for the control of vector-borne diseases. The focus of our current research has been to: i) identify and characterise endogenous transposable elements in the genomes of mosquito vectors -research has focussed on identifying both Class I and Class 11 elements and determining their structure and distribution within mosquito genomes; ii) develop and use transfection systems for mosquito cells in culture as a test bed for transformation vectors and promoters - transfection techniques, vector constructs and different promoters driving reporter genes have been utilised to optimise the transformation of both Aedes aegypti and Anopheles gambiae cells in culture; iii) identify putative promoter sequences which are induced in the female mosquito midgut when it takes a blood meal - the Anopheles gambiae trypsin gene locus has been cloned and sequenced and the intergenic regions assessed for their ability to induce reporter gene expression in mosquito gut cells. The progress we have made in each of these areas will be described and discussed in the context of our longer term aim which is to introduce genes coding for antiparasitic agents into mosquito genomes in such a way that they are expressed in the mosquito midgut and disrupt transmission of the malaria parasite. (author)

  17. Identification of mosquito repellent odours from Ocimum forskolei

    Directory of Open Access Journals (Sweden)

    Glinwood Robert

    2011-09-01

    Full Text Available Abstract Background Native mosquito repellent plants have a good potential for integrated mosquito control in local settings. Ocimum forskolei, Lamiaceae, is used in Eritrea as a spatial mosquito repellent inside houses, either through crushing fresh plants or burning dry plants. We verified whether active repellent compounds could be identified using gas-chromatography coupled electroantennogram recordings (GC-EAD with headspace extracts of crushed plants. Results EAD active compounds included (R-(--linalool, (S-(+-1-octen-3-ol, trans-caryophyllene, naphthalene, methyl salicylate, (R-(--?-copaene, methyl cinnamate and (E-ocimene. Of these compounds (R-(--linalool, methyl cinnamate and methyl salicylate reduced landing of female Aedes aegypti on human skin-odor baited tubes. The latter two are novel mosquito repellent compounds. Conclusions The identification of mosquito repellent compounds contributes to deciphering the mechanisms underlying repulsion, supporting the rational design of novel repellents. The three mosquito repellent compounds identified in this study are structurally dissimilar, which may indicate involvement of different sensory neurons in repulsion. Repulsion may well be enhanced through combining different repellent plants (or their synthetic mimics, and can be a locally sustainable part in mosquito control efforts.

  18. Human skin emanations in the host-seeking behaviour of the malaria mosquito Anopheles gambiae

    OpenAIRE

    Braks, M.A.H.

    1999-01-01

    Malaria is an infectious disease caused by a parasite ( Plasmodium spp.) that is transmitted between human individuals by mosquitoes, belonging to the order of insects, Diptera, family of Culicidae (mosquitoes) and genus of Anopheles (malaria mosquitoes). Mosquitoes feed on humans (and other animals) because they need blood for their reproduction. Like most other haematophagous insects, only the female mosquitoes bite and use the protein-rich blood meal for egg development. Whilst feeding on ...

  19. Dispersal of Culex Mosquitoes (Diptera: Culicidae) From a Wastewater Treatment Facility

    OpenAIRE

    Ciota, Alexander T.; Drummond, Cori L.; Ruby, Meghan A.; Drobnack, Jason; EBEL, GREGORY D.; KRAMER, LAURA D.

    2012-01-01

    A mark-recapture project examined dispersal and flight distances of Culex mosquitoes from a wastewater treatment plant in Albany, NY, during 2007 and 2008. A self-marking device was constructed to mark egressing mosquitoes with fluorescent marking powder. Mosquitoes were recaptured using 30 CDC miniature light traps located within a 2.0 km radius of the marking site. A total of 13 and 10 marked Culex mosquitoes were recaptured in 2007 and 2008, respectively. Culex mosquitoes traveled a minimu...

  20. UV light and urban pollution: bad cocktail for mosquitoes?

    Science.gov (United States)

    Tetreau, Guillaume; Chandor-Proust, Alexia; Faucon, Frédéric; Stalinski, Renaud; Akhouayri, Idir; Prud'homme, Sophie M; Régent-Kloeckner, Myriam; Raveton, Muriel; Reynaud, Stéphane

    2014-01-01

    Mosquito breeding sites consist of water pools, which can either be large open areas or highly covered ponds with vegetation, thus with different light exposures combined with the presence in water of xenobiotics including polycyclic aromatic hydrocarbons (PAHs) generated by urban pollution. UV light and PAHs are abiotic factors known to both affect the mosquito insecticide resistance status. Nonetheless, their potential combined effects on the mosquito physiology have never been investigated. The present article aims at describing the effects of UV exposure alongside water contamination with two major PAH pollutants (fluoranthene and benzo[a]pyrene) on a laboratory population of the yellow fever mosquito Aedes aegypti. To evaluate the effects of PAH exposure and low energetic UV (UV-A) irradiation on mosquitoes, different parameters were measured including: (1) The PAH localization and its impact on cell mortality by fluorescent microscopy; (2) The detoxification capacities (cytochrome P450, glutathione-S-transferase, esterase); (3) The responses to oxidative stress (Reactive Oxygen Species-ROS) and (4) The tolerance of mosquito larvae to a bioinsecticide (Bacillus thuringiensis subsp. israelensis-Bti) and to five chemical insecticides (DDT, imidacloprid, permethrin, propoxur and temephos). Contrasting effects regarding mosquito cell mortality, detoxification and oxidative stress were observed as being dependent on the pollutant considered, despite the fact that the two PAHs belong to the same family. Moreover, UV is able to modify pollutant effects on mosquitoes, including tolerance to three insecticides (imidacloprid, propoxur and temephos), cell damage and response to oxidative stress. Taken together, our results suggest that UV and pollution, individually or in combination, are abiotic parameters that can affect the physiology and insecticide tolerance of mosquitoes; but the complexity of their direct effect and of their interaction will require further investigation to know in which condition they can affect the efficacy of insecticide-based vector control strategies in the field. PMID:24275062

  1. Biocontrol of larval mosquitoes by Acilius sulcatus (Coleoptera: Dytiscidae

    Directory of Open Access Journals (Sweden)

    Banerjee Siddhartha S

    2008-10-01

    Full Text Available Abstract Background Problems associated with resistant mosquitoes and the effects on non-target species by chemicals, evoke a reason to find alternative methods to control mosquitoes, like the use of natural predators. In this regard, aquatic coleopterans have been explored less compared to other insect predators. In the present study, an evaluation of the role of the larvae of Acilius sulcatus Linnaeus 1758 (Coleoptera: Dytiscidae as predator of mosquito immatures was made in the laboratory. Its efficacy under field condition was also determined to emphasize its potential as bio-control agent of mosquitoes. Methods In the laboratory, the predation potential of the larvae of A. sulcatus was assessed using the larvae of Culex quinquefasciatus Say 1823 (Diptera: Culicidae as prey at varying predator and prey densities and available space. Under field conditions, the effectiveness of the larvae of A. sulcatus was evaluated through augmentative release in ten cemented tanks hosting immatures of different mosquito species at varying density. The dip density changes in the mosquito immatures were used as indicator for the effectiveness of A. sulcatus larvae. Results A single larva of A. sulcatus consumed on an average 34 IV instar larvae of Cx. quinquefasciatus in a 24 h period. It was observed that feeding rate of A. sulcatus did not differ between the light-on (6 a.m. – 6 p.m., and dark (6 p.m. – 6 a.m. phases, but decreased with the volume of water i.e., space availability. The prey consumption of the larvae of A. sulcatus differed significantly (P A. sulcatus larvae, while with the withdrawal, a significant increase (p A. sulcatus in regulating mosquito immatures. In the control tanks, mean larval density did not differ (p > 0.05 throughout the study period. Conclusion the larvae of the dytiscid beetle A. sulcatus proved to be an efficient predator of mosquito immatures and may be useful in biocontrol of medically important mosquitoes.

  2. Aedes Mosquito Saliva Modulates Rift Valley Fever Virus Pathogenicity

    Science.gov (United States)

    Le Coupanec, Alain; Babin, Divya; Fiette, Laurence; Jouvion, Grégory; Ave, Patrick; Misse, Dorothee; Bouloy, Michèle; Choumet, Valerie

    2013-01-01

    Background Rift Valley fever (RVF) is a severe mosquito-borne disease affecting humans and domestic ruminants. Mosquito saliva contains compounds that counteract the hemostatic, inflammatory, and immune responses of the host. Modulation of these defensive responses may facilitate virus infection. Indeed, Aedes mosquito saliva played a crucial role in the vector's capacity to effectively transfer arboviruses such as the Cache Valley and West Nile viruses. The role of mosquito saliva in the transmission of Rift Valley fever virus (RVFV) has not been investigated. Objective Using a murine model, we explored the potential for mosquitoes to impact the course of RVF disease by determining whether differences in pathogenesis occurred in the presence or absence of mosquito saliva and salivary gland extract. Methods C57BL/6NRJ male mice were infected with the ZH548 strain of RVFV via intraperitoneal or intradermal route, or via bites from RVFV-exposed mosquitoes. The virus titers in mosquitoes and mouse organs were determined by plaque assays. Findings After intraperitoneal injection, RVFV infection primarily resulted in liver damage. In contrast, RVFV infection via intradermal injection caused both liver and neurological symptoms and this route best mimicked the natural infection by mosquitoes. Co-injections of RVFV with salivary gland extract or saliva via intradermal route increased the mortality rates of mice, as well as the virus titers measured in several organs and in the blood. Furthermore, the blood cell counts of infected mice were altered compared to those of uninfected mice. Interpretation Different routes of infection determine the pattern in which the virus spreads and the organs it targets. Aedes saliva significantly increases the pathogenicity of RVFV. PMID:23785528

  3. Killing Vector Fields of Standard Static Space-times

    OpenAIRE

    Dobarro, Fernando; Unal, Bulent

    2008-01-01

    We consider Killing vector fields on standard static space-times and obtain equations for a vector field on a standard static space-time to be Killing. We also provide a characterization of Killing vector fields on standard static space-times with compact Riemannian parts.

  4. How blood-derived odor influences mate-choice decisions by a mosquito-eating predator

    OpenAIRE

    Cross, Fiona R.; JACKSON, ROBERT R.; Pollard, Simon D.

    2009-01-01

    Evarcha culicivora (Araneae, Salticidae) feeds indirectly on vertebrate blood by choosing, as preferred prey, bloodcarrying female mosquitoes. Mutual mate-choice behavior is also pronounced in this species. Here we show that, when E. culicivora feeds indirectly on blood, it acquires a diet-related odor that makes it more attractive to the opposite sex. The mate-choice decisions of the adults of both sexes were investigated in a series of experiments based on comparing how long the test spider...

  5. Potential Use of Mosquito’s Salivary Components as Novel Target for The Development of Transmission Blocking Vaccine (TBV

    Directory of Open Access Journals (Sweden)

    KARTIKA SENJARINI

    2013-11-01

    Full Text Available Mosquito-borne diseases are rampant in most tropical regions of the world, especially rural, forested, and coastal areas such as Indonesia. Despite long-standing chemotherapeutic intercession and vector control programs, mosquito-borne diseases exact a heavy burden on human health in Indonesia. Two major public health problems transmitted by mosquito in Indonesia are malaria and dengue haemorrhagic fever (DHF, causing millions of clinical episodes occurring annually. Malaria is now recognized as a serious re-emerging threat to public health. DHF cases were first observed in 1968; since then, the incidence has been constantly increasing and the disease is now one of the principal causes of child lethality. It has been widely observed that saliva of mosquito that transmits the diseases contains several factors that could enhance pathogen infection. Therefore, it should be possible to control pathogen transmission by vaccinating the host against the molecule(s in saliva that potentiate the infection. However, specific component as a potential target for TBV in mosquito vectors of malaria & dengue, i.e. Anopheles and Aedes aegypti, has not been identified so far. This paper wanted to elaborate the potential role of salivary component from mosquitoes, particularly from Indonesian vectors as molecular target for developing TBV against two major Mosquito borne-diseases in Indonesia i.e. malaria and DHF.

  6. Bacterial Killing by Dry Metallic Copper Surfaces?

    OpenAIRE

    Santo, Christophe Espírito; Lam, Ee Wen; Elowsky, Christian G.; Quaranta, Davide; Domaille, Dylan W.; Chang, Christopher J.; Grass, Gregor

    2010-01-01

    Metallic copper surfaces rapidly and efficiently kill bacteria. Cells exposed to copper surfaces accumulated large amounts of copper ions, and this copper uptake was faster from dry copper than from moist copper. Cells suffered extensive membrane damage within minutes of exposure to dry copper. Further, cells removed from copper showed loss of cell integrity. Acute contact with metallic copper surfaces did not result in increased mutation rates or DNA lesions. These findings are important fir...

  7. Emotion, gender and genre : Investigating The Killing

    DEFF Research Database (Denmark)

    Agger, Gunhild

    2011-01-01

    Traditionally, Scandinavian TV crime fiction has been regarded as a public arena for critical exhibition of and debate about salient features in contemporary social development. To explain the acknowledged impact of this kind of crime fiction, it is necessary to involve the notions of emotion and gender in combination with the mixing of genres, as especially the thriller and the melodrama have invaded the police procedural. This is demonstrated in an analysis of The Killing.

  8. Deprivations, futures and the wrongness of killing

    OpenAIRE

    Marquis, D.

    2001-01-01

    In my essay, Why abortion is immoral, I criticised discussions of the morality of abortion in which the crucial issue is whether fetuses are human beings or whether fetuses are persons. Both argument strategies are inadequate because they rely on indefensible assumptions. Why should being a human being or being a person make a moral difference? I argued that the correct account of the morality of abortion should be based upon a defensible account of why killing children and adults is wrong. I...

  9. Aparelho de sucção tipo aspirador para captura de mosquitos A "vacuum-cleaner" type of suction apparatus for the collection of mosquitoes

    Directory of Open Access Journals (Sweden)

    Délsio Natal

    1984-10-01

    Full Text Available É feita a descrição de aparelho portátil de sucção tipo aspirador, para captura de mosquitos Culicidae. São sugeridas adaptações para coletas em diferentes situações. São feitos comentários sobre sua aplicação em pesquisa de mosquitos.A portable suction apparatus, which functions like a vacuum cleaner used for the collection of Culicidae mosquitoes is described. Adaptations for collecting in differents situations are suggested and some comments about its application in mosquitoes surveys are made.

  10. Genetic Methods for Control of Mosquitoes

    International Nuclear Information System (INIS)

    This summary of past experiments and pilot projects on the genetic control of mosquitoes is not intended to be an exhaustive review. Emphasis has been placed on: 1) successful research efforts on the use of the sterile insect technique (SIT) and the synthesis of useful heritable chromosomal aberrations, 2) the technical limitations in our present ability to use SIT, 3) the need for genetic evaluation of the structure of natural populations, and 4) a look at the future impact of recombinant DNA methods on genetic control. A generally optimistic point of view of the current and future situations from the author's perspective will be expressed, with emphasis on successful research efforts. Past failures will not be ignored, but neither will they be presented as irrefutable evidence of doom for genetic control.

  11. Mosquitoes actively remove drops deposited by fog and dew.

    Science.gov (United States)

    Dickerson, Andrew K; Hu, David L

    2014-12-01

    We report mosquito behaviors for removing accumulated drops of water which would otherwise increase the energy expended during takeoff and free flight. These techniques take advantage of the insect's small size and great structural strength. To dry their wings before takeoff, mosquitoes employ a flutter stroke, at double the wingbeat frequency of normal flight, generating nearly 2500 gravities of acceleration. Mosquitoes may also remove drops by the respective accelerations associated with takeoff and collision with the ground. We correlate the accelerations and size of drops ejected using a simple model involving the drop's inertial force and surface tension. We note mosquitoes may use similar techniques to remove synthetic drops, making our observations applicable for understanding the resistance of insects to insecticides. PMID:24876192

  12. Comparative repellency of 38 essential oils against mosquito bites.

    Science.gov (United States)

    Trongtokit, Yuwadee; Rongsriyam, Yupha; Komalamisra, Narumon; Apiwathnasorn, Chamnarn

    2005-04-01

    The mosquito repellent activity of 38 essential oils from plants at three concentrations was screened against the mosquito Aedes aegypti under laboratory conditions using human subjects. On a volunteer's forearm, 0.1 mL of oil was applied per 30 cm2 of exposed skin. When the tested oils were applied at a 10% or 50% concentration, none of them prevented mosquito bites for as long as 2 h, but the undiluted oils of Cymbopogon nardus (citronella), Pogostemon cablin (patchuli), Syzygium aromaticum (clove) and Zanthoxylum limonella (Thai name: makaen) were the most effective and provided 2 h of complete repellency. From these initial results, three concentrations (10%, 50% and undiluted) of citronella, patchouli, clove and makaen were selected for repellency tests against Culex quinquefasciatus and Anopheles dirus. As expected, the undiluted oil showed the highest protection in each case. Clove oil gave the longest duration of 100% repellency (2-4 h) against all three species of mosquito. PMID:16041723

  13. Dirofilaria repens microfilariae in Aedes vexans mosquitoes in Slovakia.

    Czech Academy of Sciences Publication Activity Database

    Bocková, E.; Rudolf, Ivo; Ko?išová, A.; Betášová, Lenka; Venclíková, Kristýna; Mendel, Jan; Hubálek, Zden?k

    2013-01-01

    Ro?. 112, ?. 10 (2013), s. 3465-3470. ISSN 0932-0113 Institutional support: RVO:68081766 Keywords : Dirofilaria * mosquitoes * Aedes vexans Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 2.327, year: 2013

  14. Gradual diffusive capture: slow death by many mosquito bites

    International Nuclear Information System (INIS)

    We study the dynamics of a single diffusing particle (a ‘man’) with diffusivity DM that is attacked by another diffusing particle (a ‘mosquito’) with fixed diffusivity Dm. Each time the mosquito meets and bites the man, the diffusivity of the man is reduced by a fixed amount, while the diffusivity of the mosquito is unchanged. The mosquito is also displaced by a small distance ±a with respect to the man after each encounter. The man is defined as dead when DM reaches zero. At the moment when the man dies, his probability distribution of displacements x is given by a Cauchy form, which asymptotically decays as x?2, while the distribution of times t when the man dies decays asymptotically as t?3/2, which has the same form as the one-dimensional first-passage probability. (paper)

  15. Microinjection of A. aegypti Embryos to Obtain Transgenic Mosquitoes

    OpenAIRE

    Jasinskiene, Nijole; Juhn, Jennifer; JAMES, ANTHONY A.

    2007-01-01

    In this video, Nijole Jasinskiene demonstrates the methodology employed to generate transgenic Aedes aegypti mosquitoes, which are vectors for dengue fever. The techniques for correctly preparing microinjection needles, dessicating embryos, and performing microinjection are demonstrated.

  16. Vector competence of New Zealand mosquitoes for selected arboviruses.

    Science.gov (United States)

    Kramer, Laura D; Chin, Pam; Cane, Rachel P; Kauffman, Elizabeth B; Mackereth, Graham

    2011-07-01

    New Zealand (NZ) historically has been free of arboviral activity with the exception of Whataroa virus (Togaviridae: Alphavirus), which is established in bird populations and is transmitted by local mosquitoes. This naive situation is threatened by global warming, invasive mosquitoes, and tourism. To determine the threat of selected medically important arboviruses to NZ, vector competence assays were conducted using field collected endemic and introduced mosquito species. Four alphaviruses (Togaviridae): Barmah Forest virus, Chikungunya virus, Ross River virus, and Sindbis virus, and five flaviviruses (Flaviviridae): Dengue virus 2, Japanese encephalitis virus, Murray Valley encephalitis virus, West Nile virus, and Yellow fever virus were evaluated. Results indicate some NZ mosquito species are highly competent vectors of selected arboviruses, particularly alphaviruses, and may pose a threat were one of these arboviruses introduced at a time when the vector was prevalent and the climatic conditions favorable for virus transmission. PMID:21734146

  17. Toxicity of a plant based mosquito repellent/killer

    OpenAIRE

    Singh, Bhoopendra; Singh, Prakash Raj; Mohanty, Manoj Kumar

    2012-01-01

    The mission to make humans less attractive to mosquitoes has fuelled decades of scientific research on mosquito behaviour and control. The search for the perfect topical insect repellent/killer continues. This analysis was conducted to review and explore the scientific information on toxicity produced by the ingredients/contents of a herbal product. In this process of systemic review the following methodology was applied. By doing a MEDLINE search with key words of selected plants, plant base...

  18. Transcriptome Analysis of Aedes aegypti Transgenic Mosquitoes with Altered Immunity

    OpenAIRE

    Zou, Zhen; Souza-neto, Jayme; Xi, Zhiyong; Kokoza, Vladimir; Shin, Sang Woon; Dimopoulos, George; Raikhel, Alexander

    2011-01-01

    The mosquito immune system is involved in pathogen-elicited defense responses. The NF-?B factors REL1 and REL2 are downstream transcription activators of Toll and IMD immune pathways, respectively. We have used genome-wide microarray analyses to characterize fat-body-specific gene transcript repertoires activated by either REL1 or REL2 in two transgenic strains of the mosquito Aedes aegypti. Vitellogenin gene promoter was used in each transgenic strain to ectopically express either REL1 (REL...

  19. The basic rules and methods of mosquito rearing (Aedes aegypti)

    OpenAIRE

    Imam, Hashmat; Zarnigar; Sofi, Ghulamuddin; Seikh, Aziz

    2014-01-01

    The rearing of Aedes mosquitoes is complex and demanding for several reasons. Aedes larvae are affected by temperature, density and available nutrition, mating is not necessarily accomplished naturally and females need a blood meal to develop eggs. The climate chambers where the mosquitoes are kept are warm and sweaty. Due to these tropical conditions the larvae develop fast and need to be cared for daily. The Laboratory of Entomology in National Institute of Malaria Research Bangalore has cu...

  20. Fungal infection counters insecticide resistance in African malaria mosquitoes

    OpenAIRE

    Farenhorst, M.; J. C. Mouatcho; Kikankie, C.K.; Brooke, B.D.; Hunt, R.H.; M. B. Thomas; Koekemoer, L. L.; Knols, B G J; M. Coetzee

    2009-01-01

    The evolution of insecticide resistance in mosquitoes is threatening the effectiveness and sustainability of malaria control programs in various parts of the world. Through their unique mode of action, entomopathogenic fungi provide promising alternatives to chemical control. However, potential interactions between fungal infection and insecticide resistance, such as cross-resistance, have not been investigated. We show that insecticide-resistant Anopheles mosquitoes remain susceptible to inf...

  1. EFFICACY OF AGERATUM CONYZOIDES AGAINST THE CONTROL OF MOSQUITOES

    OpenAIRE

    Neetu Arya et al.

    2011-01-01

    Mosquitoes transmit serious human diseases causing millions of deaths every year. Phytochemistry has proven that there are potential mosquito control agents and also alternatives to synthetic insecticides. The present paper reports Ageratum conyzoides commonly known as Kubhi in Hindi of family Astereacae. The plant after proper identification was collected shade dried and powdered to the fine mesh size. 5 different concentrations were used against IInd and IVth instar of Anapheles stephensi. ...

  2. Statics and dynamics of malaria infection in Anopheles mosquitoes

    OpenAIRE

    Ellis McKenzie F; Smith David L

    2004-01-01

    Abstract The classic formulae in malaria epidemiology are reviewed that relate entomological parameters to malaria transmission, including mosquito survivorship and age-at-infection, the stability index (S), the human blood index (HBI), proportion of infected mosquitoes, the sporozoite rate, the entomological inoculation rate (EIR), vectorial capacity (C) and the basic reproductive number (R0). The synthesis emphasizes the relationships among classic formulae and reformulates a simple dynamic...

  3. Pesticides and public health: integrated methods of mosquito management.

    OpenAIRE

    Rose, R. I.

    2001-01-01

    Pesticides have a role in public health as part of sustainable integrated mosquito management. Other components of such management include surveillance, source reduction or prevention, biological control, repellents, traps, and pesticide-resistance management. We assess the future use of mosquito control pesticides in view of niche markets, incentives for new product development, Environmental Protection Agency registration, the Food Quality Protection Act, and improved pest management strate...

  4. Malaria Situation and Anopheline Mosquitoes in Qom Province, Central Iran

    OpenAIRE

    MR Abai; Saghafipour, A; B Farzinnia

    2010-01-01

    "nAbstract "nBackground: The aims of this study was to analysis the current situation of malaria and to find the distribution of anopheline mosquitoes, as probable vectors of the disease, in Qom Province, central Iran. "nMethods: This study was carried out in two parts. First stage was data collection about malaria cases using recorded documents of patients in the Province health center, during 2001–2008. The second stage was entomological survey conducted by mosquito...

  5. Nature or nurture in mosquito resistance to malaria?

    OpenAIRE

    Hurd, Hilary

    2007-01-01

    The genetic basis of mosquito resistance to malaria parasites is well established and currently receives a lot of attention. However this is not the sole determinant of the success or failure of an infection. In a recent article, Lambrechts and colleagues report the influence of the quality of the external environment of a mosquito on infection. They indicate that external variations could substantially reduce the importance of resistance genes in determining infection by malaria parasites. F...

  6. Factors influencing stakeholders attitudes toward genetically modified aedes mosquito.

    Science.gov (United States)

    Amin, Latifah; Hashim, Hasrizul

    2015-06-01

    Dengue fever is a debilitating and infectious disease that could be life-threatening. It is caused by the dengue virus which affects millions of people in the tropical area. Currently, there is no cure for the disease as there is no vaccine available. Thus, prevention of the vector population using conventional methods is by far the main strategy but has been found ineffective. A genetically modified (GM) mosquito is among the favoured alternatives to curb dengue fever in Malaysia. Past studies have shown that development and diffusion of gene technology products depends heavily upon public acceptance. The purpose of this study is to identify the relevant factors influencing stakeholders' attitudes toward the GM Aedes mosquito and to analyse the relationships between all the factors using the structural equation model. A survey was carried out on 509 respondents from various stakeholder groups in the Klang Valley region of Malaysia. Results of the survey have confirmed that public perception towards complex issues such as gene technology should be seen as a multi-faceted process. The perceived benefit-perceived risk balance is very important in determining the most predominant predictor of attitudes toward a GM mosquito. In this study the stakeholders perceived the benefit of the GM mosquito as outweighing its risk, translating perceived benefit as the most important direct predictor of attitudes toward the GM mosquito. Trust in key players has a direct influence on attitudes toward the GM mosquito while moral concern exhibited an indirect influence through perceived benefits. Other factors such as attitudes toward technology and nature were also indirect predictors of attitudes toward the GM mosquito while religiosity and engagement did not exhibited any significant roles. The research findings serve as a useful database to understand public acceptance and the social construct of public attitudes towards the GM mosquito to combat dengue. PMID:24906652

  7. Energy Metabolism During Diapause in Culex pipiens Mosquitoes

    OpenAIRE

    Zhou, Guoli; Miesfeld, Roger L

    2008-01-01

    Diapause in overwintering adult female Culex pipiens mosquitoes plays an important role in the transmission of West Nile and other encephalitis-inducing flaviviruses. To investigate the dynamic metabolic processes that control Cx. pipiens diapause, we used radioactive tracer techniques with [14C]-glucose to investigate the metabolic fate and flux of glucose in adult mosquitoes reared under diapause (18°C, short day) and nondiapause (27°C, long day) conditions. We found that by 72 hours post...

  8. Species Composition and Relative Abundance of Mosquitoes in Swat, Pakistan

    Directory of Open Access Journals (Sweden)

    Ikram Ilahi

    2013-04-01

    Full Text Available A comprehensive survey of mosquitoes (Diptera: Culicidae was conducted in Swat Pakistan, from April to September during 2000. The survey involved the sampling of both, adult and immature stages of mosquitoes, and recovered a total of 21 species in five genera. Sampling of adult mosquitoes involved Pyrethrum spray collections, Man-biting collections, and Animal-biting collection. Immature stages of mosquitoes were collected from variety of habitats including springs, irrigation channels, rice fields, marshes, temporary pools, construction pools, agriculture pools, river margins, ditches, waste water drains, wells and tree holes. During the study most of the species built up their populations in June, July and August, while a few increased their populations in September. During the survey of immature stages, from a total of 138 samples taken, Cx. quinquefasciatus showed maximum frequency of occurrence (recovered from 48 samples followed by An. maculatus (17 samples, Cx. pseudovishnui (14 samples, An. annularis and An. stephensi (13 samples each, Cx. bitaeniorhynchus (11 samples, An. splendidus (5 samples and Cx. theileri (4 samples. The rest of the species occurred infrequently. The observations on habitat specificity of different species of mosquitoes showed the rice fields as the most favorable site for mosquito breeding (harboring 12 species followed by river margins (five species and temporary pools and springs (four species each. During this study Ae. aegypti was recovered from tyres in Mingora; it was not reported earlier from Swat.

  9. Mosquito larvicidal and ovicidal activity of puffer fish extracts against Anopheles stephensi, Culex quinquefasciatus and Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Samidurai, Kaliyaperumal; Mathew, Nisha

    2013-03-01

    The extracts of liver (LE), ovary (OE), skin (SE) and muscle (ME) tissues of four species of puffer fishes viz., Arothron hispidus, Lagocephalus inermis, Lagocephalus scleratus and Chelonodon patoca were evaluated against larvae and eggs of three mosquito vectors, Anopheles stephensi, Culex quinquefasciatus and Aedes aegypti. The LC50 values were 1194.26, 1382.73 (LE); 1421.42, 1982.73 (OE); 7116.86, 15038.98 (ME) and 10817.8 ppm (SE) for An. stephensi and Cx. quinquefasciatus respectively for A. hispidus. In the case of L. inermis, the LC50 values were 1163.83, 1556.1 and 2426.38 (LE); 1653.53, 2734.74 (OE); 6067.47 (ME) and 10283.04 ppm (SE) for An. stephensi, Cx. quinquefasciatus and Ae. aegypti respectively. The LC50 values were 1509.98, 1608.69 (LE) and 1414.9, 2278.69 ppm (OE) for An. stephensi and Cx. quinquefasciatus respectively for the extracts of L. scleratus. In the case C. patoca extracts the LC50 values were 1182.29, 1543.00, 2441.03 (LE) and 1076.13, 2582.11 ppm (OE) for An. stephensi, Cx. quinquefasciatus and Ae. aegypti respectively. OE and LE of all puffer fishes exhibited zero percent egg hatchability from 600 to 1000 ppm against eggs of An. stephensi and Cx. quinquefasciatus. This study shows that puffer toxins are effective in killing the larvae and eggs of mosquitoes. PMID:23665705

  10. 3-Oxoisoxazole-2(3H)-carboxamides and isoxazol-3-yl carbamates: Resistance-breaking acetylcholinesterase inhibitors targeting the malaria mosquito, Anopheles gambiae.

    Science.gov (United States)

    Verma, Astha; Wong, Dawn M; Islam, Rafique; Tong, Fan; Ghavami, Maryam; Mutunga, James M; Slebodnick, Carla; Li, Jianyong; Viayna, Elisabet; Lam, Polo C-H; Totrov, Maxim M; Bloomquist, Jeffrey R; Carlier, Paul R

    2015-03-15

    To identify potential selective and resistance-breaking mosquitocides against the African malaria vector Anopheles gambiae, we investigated the acetylcholinesterase (AChE) inhibitory and mosquitocidal properties of isoxazol-3-yl dimethylcarbamates (15), and the corresponding 3-oxoisoxazole-2(3H)-dimethylcarboxamide isomers (14). In both series, compounds were found with excellent contact toxicity to wild-type susceptible (G3) strain and multiply resistant (Akron) strain mosquitoes that carry the G119S resistance mutation of AChE. Compounds possessing good to excellent toxicity to Akron strain mosquitoes inhibit the G119S mutant of An. gambiae AChE (AgAChE) with ki values at least 10- to 600-fold higher than that of propoxur, a compound that does not kill Akron mosquitoes at the highest concentration tested. On average, inactivation of WT AgAChE by dimethylcarboxamides 14 was 10-20 fold faster than that of the corresponding isoxazol-3-yl dimethylcarbamates 15. X-ray crystallography of dimethylcarboxamide 14d provided insight into that reactivity, a finding that may explain the inhibitory power of structurally-related inhibitors of hormone-sensitive lipase. Finally, human/An. gambiae AChE inhibition selectivities of these compounds were low, suggesting the need for additional structural modification. PMID:25684426

  11. Micro-sociology of mass rampage killings.

    Science.gov (United States)

    Collins, Randall

    2014-01-01

    Spectacular but very rare violent events such as mass killings by habitual non-criminals cannot be explained by factors which are very widespread, such as possession of firearms, being a victim of bullying, an introvert, or a career failure. A stronger clue is clandestine preparation of attack by one or two individuals, against randomly chosen representatives of a hated collective identity. Mass killers develop a deep back-stage, obsessed with planning their attack, overcoming social inferiority and isolation by an emotion of clandestine excitement. PMID:25179819

  12. Surface gravities for non-Killing horizons

    International Nuclear Information System (INIS)

    There are many logically and computationally distinct characterizations of the surface gravity of a horizon, just as there are many logically rather distinct notions of horizon. Fortunately, in standard general relativity, for stationary horizons, these characterizations are degenerate. However, in modified gravity, or in analogue spacetimes, horizons may be non-Killing or even non-null, and hence these degeneracies can be lifted. We present a brief overview of the key issues, specifically focusing on horizons in analogue spacetimes and universal horizons in modified gravity. (paper)

  13. A review of mixed malaria species infections in anopheline mosquitoes

    Directory of Open Access Journals (Sweden)

    Day Nicholas PJ

    2011-08-01

    Full Text Available Abstract Background In patients with malaria mixed species infections are common and under reported. In PCR studies conducted in Asia mixed infection rates often exceed 20%. In South-East Asia, approximately one third of patients treated for falciparum malaria experience a subsequent Plasmodium vivax infection with a time interval suggesting relapse. It is uncertain whether the two infections are acquired simultaneously or separately. To determine whether mixed species infections in humans are derived from mainly from simultaneous or separate mosquito inoculations the literature on malaria species infection in wild captured anopheline mosquitoes was reviewed. Methods The biomedical literature was searched for studies of malaria infection and species identification in trapped wild mosquitoes and artificially infected mosquitoes. The study location and year, collection methods, mosquito species, number of specimens, parasite stage examined (oocysts or sporozoites, and the methods of parasite detection and speciation were tabulated. The entomological results in South East Asia were compared with mixed infection rates documented in patients in clinical studies. Results In total 63 studies were identified. Individual anopheline mosquitoes were examined for different malaria species in 28 of these. There were 14 studies from Africa; four with species evaluations in individual captured mosquitoes (SEICM. One study, from Ghana, identified a single mixed infection. No mixed infections were identified in Central and South America (seven studies, two SEICM. 42 studies were conducted in Asia and Oceania (11 from Thailand; 27 SEICM. The proportion of anophelines infected with Plasmodium falciparum parasites only was 0.51% (95% CI: 0.44 to 0.57%, for P. vivax only was 0.26% (95% CI: 0.21 to 0.30%, and for mixed P. falciparum and P. vivax infections was 0.036% (95% CI: 0.016 to 0.056%. The proportion of mixed infections in mosquitoes was significantly higher than expected by chance (P Conclusions There are relatively few data on mixed infection rates in mosquitoes from Africa. Mixed species malaria infections may be acquired by simultaneous inoculation of sporozoites from multiply infected anopheline mosquitoes but this is relatively unusual. In South East Asia, where P. vivax infection follows P. falciparum malaria in one third of cases, the available entomological information suggests that the majority of these mixed species malaria infections are acquired from separate inoculations.

  14. Response of the mosquito protein interaction network to dengue infection

    Directory of Open Access Journals (Sweden)

    Pike Andrew D

    2010-06-01

    Full Text Available Abstract Background Two fifths of the world's population is at risk from dengue. The absence of effective drugs and vaccines leaves vector control as the primary intervention tool. Understanding dengue virus (DENV host interactions is essential for the development of novel control strategies. The availability of genome sequences for both human and mosquito host greatly facilitates genome-wide studies of DENV-host interactions. Results We developed the first draft of the mosquito protein interaction network using a computational approach. The weighted network includes 4,214 Aedes aegypti proteins with 10,209 interactions, among which 3,500 proteins are connected into an interconnected scale-free network. We demonstrated the application of this network for the further annotation of mosquito proteins and dissection of pathway crosstalk. Using three datasets based on physical interaction assays, genome-wide RNA interference (RNAi screens and microarray assays, we identified 714 putative DENV-associated mosquito proteins. An integrated analysis of these proteins in the network highlighted four regions consisting of highly interconnected proteins with closely related functions in each of replication/transcription/translation (RTT, immunity, transport and metabolism. Putative DENV-associated proteins were further selected for validation by RNAi-mediated gene silencing, and dengue viral titer in mosquito midguts was significantly reduced for five out of ten (50.0% randomly selected genes. Conclusions Our results indicate the presence of common host requirements for DENV in mosquitoes and humans. We discuss the significance of our findings for pharmacological intervention and genetic modification of mosquitoes for blocking dengue transmission.

  15. Elizabethkingia anophelis: molecular manipulation and interactions with mosquito hosts.

    Science.gov (United States)

    Chen, Shicheng; Bagdasarian, Michael; Walker, Edward D

    2015-03-01

    Flavobacteria (members of the family Flavobacteriaceae) dominate the bacterial community in the Anopheles mosquito midgut. One such commensal, Elizabethkingia anophelis, is closely associated with Anopheles mosquitoes through transstadial persistence (i.e., from one life stage to the next); these and other properties favor its development for paratransgenic applications in control of malaria parasite transmission. However, the physiological requirements of E. anophelis have not been investigated, nor has its capacity to perpetuate despite digestion pressure in the gut been quantified. To this end, we first developed techniques for genetic manipulation of E. anophelis, including selectable markers, reporter systems (green fluorescent protein [GFP] and NanoLuc), and transposons that function in E. anophelis. A flavobacterial expression system based on the promoter PompA was integrated into the E. anophelis chromosome and showed strong promoter activity to drive GFP and NanoLuc reporter production. Introduced, GFP-tagged E. anophelis associated with mosquitoes at successive developmental stages and propagated in Anopheles gambiae and Anopheles stephensi but not in Aedes triseriatus mosquitoes. Feeding NanoLuc-tagged cells to A. gambiae and A. stephensi in the larval stage led to infection rates of 71% and 82%, respectively. In contrast, a very low infection rate (3%) was detected in Aedes triseriatus mosquitoes under the same conditions. Of the initial E. anophelis cells provided to larvae, 23%, 71%, and 85% were digested in A. stephensi, A. gambiae, and Aedes triseriatus, respectively, demonstrating that E. anophelis adapted to various mosquito midgut environments differently. Bacterial cell growth increased up to 3-fold when arginine was supplemented in the defined medium. Furthermore, the number of NanoLuc-tagged cells in A. stephensi significantly increased when arginine was added to a sugar diet, showing it to be an important amino acid for E. anophelis. Animal erythrocytes promoted E. anophelis growth in vivo and in vitro, indicating that this bacterium could obtain nutrients by participating in erythrocyte lysis in the mosquito midgut. PMID:25595771

  16. MosquitoMap and the Mal-area calculator: new web tools to relate mosquito species distribution with vector borne disease

    Directory of Open Access Journals (Sweden)

    Christensen Jamie

    2010-02-01

    Full Text Available Abstract Background Mosquitoes are important vectors of diseases but, in spite of various mosquito faunistic surveys globally, there is a need for a spatial online database of mosquito collection data and distribution summaries. Such a resource could provide entomologists with the results of previous mosquito surveys, and vector disease control workers, preventative medicine practitioners, and health planners with information relating mosquito distribution to vector-borne disease risk. Results A web application called MosquitoMap was constructed comprising mosquito collection point data stored in an ArcGIS 9.3 Server/SQL geodatabase that includes administrative area and vector species x country lookup tables. In addition to the layer containing mosquito collection points, other map layers were made available including environmental, and vector and pathogen/disease distribution layers. An application within MosquitoMap called the Mal-area calculator (MAC was constructed to quantify the area of overlap, for any area of interest, of vector, human, and disease distribution models. Data standards for mosquito records were developed for MosquitoMap. Conclusion MosquitoMap is a public domain web resource that maps and compares georeferenced mosquito collection points to other spatial information, in a geographical information system setting. The MAC quantifies the Mal-area, i.e. the area where it is theoretically possible for vector-borne disease transmission to occur, thus providing a useful decision tool where other disease information is limited. The Mal-area approach emphasizes the independent but cumulative contribution to disease risk of the vector species predicted present. MosquitoMap adds value to, and makes accessible, the results of past collecting efforts, as well as providing a template for other arthropod spatial databases.

  17. The eyeball killer: serial killings with postmortem globe enucleation.

    Science.gov (United States)

    Coyle, Julie; Ross, Karen F; Barnard, Jeffrey J; Peacock, Elizabeth; Linch, Charles A; Prahlow, Joseph A

    2015-05-01

    Although serial killings are relatively rare, they can be the cause of a great deal of anxiety while the killer remains at-large. Despite the fact that the motivations for serial killings are typically quite complex, the psychological analysis of a serial killer can provide valuable insight into how and why certain individuals become serial killers. Such knowledge may be instrumental in preventing future serial killings or in solving ongoing cases. In certain serial killings, the various incidents have a variety of similar features. Identification of similarities between separate homicidal incidents is necessary to recognize that a serial killer may be actively killing. In this report, the authors present a group of serial killings involving three prostitutes who were shot to death over a 3-month period. Scene and autopsy findings, including the unusual finding of postmortem enucleation of the eyes, led investigators to recognize the serial nature of the homicides. PMID:25682709

  18. Fate of blood meal iron in mosquitoes.

    Science.gov (United States)

    Zhou, Guoli; Kohlhepp, Pete; Geiser, Dawn; Frasquillo, Maria Del Carmen; Vazquez-Moreno, Luz; Winzerling, Joy J

    2007-11-01

    Iron is an essential element of living cells and organisms as a component of numerous metabolic pathways. Hemoglobin and ferric-transferrin in vertebrate host blood are the two major iron sources for female mosquitoes. We used inductively coupled plasma mass spectrometry (ICP-MS) and radioisotope labeling to quantify the fate of iron supplied from hemoglobin or as transferrin in Aedes aegypti. At the end of the first gonotrophic cycle, approximately 87% of the ingested total meal heme iron was excreted, while 7% was distributed into the eggs and 6% was stored in different tissues. In contrast, approximately 8% of the iron provided as transferrin was excreted and of that absorbed, 77% was allocated to the eggs and 15% distributed in the tissues. Further analyses indicate that of the iron supplied in a blood meal, approximately 7% appears in the eggs and of this iron 98% is from hemoglobin and 2% from ferric-transferrin. Whereas, of iron from a blood meal retained in body of the female, approximately 97% is from heme and transferrin. Evaluation of iron-binding proteins in hemolymph and egg following intake of (59)Fe-transferrin revealed that ferritin is iron loaded in these animals, and indicate that this protein plays a critical role in meal iron transport and iron storage in eggs in A. aegypti. PMID:17689557

  19. Lyme disease assay which detects killed Borrelia burgdorferi.

    OpenAIRE

    Callister, S. M.; Schell, R F; Lovrich, S D

    1991-01-01

    We developed an in vitro assay showing that Borrelia burgdorferi organisms were killed by serum from patients with Lyme disease. Twenty of 20 Lyme disease serum samples caused B. burgdorferi killing in a range of 36 to 99% compared with the mean number of viable spirochetes when sera from 10 healthy individuals were used. The percentage of killing of B. burgdorferi increased with convalescent serum from patients with early Lyme disease. The borreliacidal activity was detectable in some sera d...

  20. Targeted killing, unmanned aerial vehicles and EU policy

    OpenAIRE

    Bhuta, Nehal; Kreß, Claus; Seiderman, Ian; Heyns, Christof; Melzer, Nils; Scheinin, Martin; Benvenisti, Eyal; Dworkin, Anthony

    2013-01-01

    This paper collects 7 expert memoranda prepared for the Global Governance Program's High-Level Policy Seminar on Targeted Killing, Unmanned Aerial Vehicles and EU Policy. In these memoranda, noted experts address the legality of the US policy of targeted killings under the international law of self-defence, international humanitarian law and international human rights law. Also addressed is the comparative example of Israel, and its legal framework regulating targeted killing. The concluding ...

  1. Killing sections and sigma models with Lie algebroid targets

    CERN Document Server

    Bruce, Andrew James

    2015-01-01

    We define and examine the notion of a Killing section of a Riemannian Lie algebroid as a natural generalisation of a Killing vector field. We show that the various expression for a vector field to be Killing naturally generalise to the setting of Lie algebroids. As an application we examine the internal symmetries of a class of sigma models for which the target space is a Riemannian Lie algebroid. Critical points of these sigma models are interpreted as generalised harmonic maps.

  2. Birkhoff theorem and conformal Killing-Yano tensors

    CERN Document Server

    Ferrando, Joan Josep

    2015-01-01

    We analyze the main geometric conditions imposed by the hypothesis of the Jebsen-Birkhoff theorem. We show that the result (existence of an additional Killing vector) does not necessarily require a three-dimensional isometry group on two-dimensional orbits but only the existence of a conformal Killing-Yano tensor. In this approach the (additional) isometry appears as the known invariant Killing vector that the ${\\cal D}$-metrics admit.

  3. European Surveillance for West Nile Virus in Mosquito Populations

    Directory of Open Access Journals (Sweden)

    Nicholas Johnson

    2013-10-01

    Full Text Available A wide range of arthropod-borne viruses threaten both human and animal health either through their presence in Europe or through risk of introduction. Prominent among these is West Nile virus (WNV, primarily an avian virus, which has caused multiple outbreaks associated with human and equine mortality. Endemic outbreaks of West Nile fever have been reported in Italy, Greece, France, Romania, Hungary, Russia and Spain, with further spread expected. Most outbreaks in Western Europe have been due to infection with WNV Lineage 1. In Eastern Europe WNV Lineage 2 has been responsible for human and bird mortality, particularly in Greece, which has experienced extensive outbreaks over three consecutive years. Italy has experienced co-circulation with both virus lineages. The ability to manage this threat in a cost-effective way is dependent on early detection. Targeted surveillance for pathogens within mosquito populations offers the ability to detect viruses prior to their emergence in livestock, equine species or human populations. In addition, it can establish a baseline of mosquito-borne virus activity and allow monitoring of change to this over time. Early detection offers the opportunity to raise disease awareness, initiate vector control and preventative vaccination, now available for horses, and encourage personal protection against mosquito bites. This would have major benefits through financial savings and reduction in equid morbidity/mortality. However, effective surveillance that predicts virus outbreaks is challenged by a range of factors including limited resources, variation in mosquito capture rates (too few or too many, difficulties in mosquito identification, often reliant on specialist entomologists, and the sensitive, rapid detection of viruses in mosquito pools. Surveillance for WNV and other arboviruses within mosquito populations varies between European countries in the extent and focus of the surveillance. This study reviews the current status of WNV in mosquito populations across Europe and how this is informing our understanding of virus epidemiology. Key findings such as detection of virus, presence of vector species and invasive mosquito species are summarized, and some of the difficulties encountered when applying a cost-effective surveillance programme are highlighted.

  4. Antibacterial activity of silver-killed bacteria: the "zombies" effect

    Science.gov (United States)

    Wakshlak, Racheli Ben-Knaz; Pedahzur, Rami; Avnir, David

    2015-04-01

    We report a previously unrecognized mechanism for the prolonged action of biocidal agents, which we denote as the zombies effect: biocidally-killed bacteria are capable of killing living bacteria. The concept is demonstrated by first killing Pseudomonas aeruginosa PAO1 with silver nitrate and then challenging, with the dead bacteria, a viable culture of the same bacterium: Efficient antibacterial activity of the killed bacteria is observed. A mechanism is suggested in terms of the action of the dead bacteria as a reservoir of silver, which, due to Le-Chatelier's principle, is re-targeted to the living bacteria. Langmuirian behavior, as well as deviations from it, support the proposed mechanism.

  5. Toxicity of a plant based mosquito repellent/killer

    Science.gov (United States)

    Singh, Prakash Raj; Mohanty, Manoj Kumar

    2012-01-01

    The mission to make humans less attractive to mosquitoes has fuelled decades of scientific research on mosquito behaviour and control. The search for the perfect topical insect repellent/killer continues. This analysis was conducted to review and explore the scientific information on toxicity produced by the ingredients/contents of a herbal product. In this process of systemic review the following methodology was applied. By doing a MEDLINE search with key words of selected plants, plant based insect repellents/killers pertinent articles published in journals and authentic books were reviewed. The World Wide Web and the Extension Toxicity Network database (IPCS-ITOX) were also searched for toxicology data and other pertinent information. Repellents do not all share a single mode of action and surprisingly little is known about how repellents act on their target insects. Moreover, different mosquito species may react differently to the same repellent. After analysis of available data and information on the ingredient, of the product in relation to medicinal uses, acute and chronic toxicity of the selected medicinal plants, it can be concluded that the ingredients included in the herbal product can be used as active agents against mosquitoes. If the product which contains the powder of the above said plants is applied with care and safety, it is suitable fo use as a mosquito repellent/killer. PMID:23554562

  6. Malaria Mosquitoes Host-Locate and Feed upon Caterpillars

    Science.gov (United States)

    George, Justin; Blanford, Simon; Thomas, Matthew B.; Baker, Thomas C.

    2014-01-01

    Adult female mosquitoes need blood to develop their eggs and both sexes use nectar and honeydew as carbohydrate resources for flight, survival and to enhance reproduction. However, there are also a few reports in the literature of mosquitoes feeding on haemolymph of soft-bodied insects such as caterpillars. The frequency and significance of this entomophagous behavior is not well understood, but is thought to be a vestige of ancestral feeding behavior or an opportunistic behavior that has evolved over time. In our current paper we investigated the extent to which the malaria mosquito, Anopheles stephensi, is attracted to, and can successfully feed on, larvae of two common moth species, Manduca sexta and Heliothis subflexa. Using y-tube olfactometer assays we found that female An. stephensi readily flew upwind to and landed on the caterpillars of both moth species. The nature of the volatile cues used in host location remains unclear but respirometer studies suggest a possible role of CO2. Laboratory cage assays further showed that the female mosquitoes were able to actively feed on moth larvae and gain sufficient nutritional benefit to influence survival. The extent to which such an opportunistic behavior occurs in the field has yet to be explored but our results suggest that this haemolymph feeding behavior could play a role in malaria mosquito life history and could provide a novel mechanism for horizontal transmission of pathogens and other micro-organisms between hosts. PMID:25372720

  7. DNA barcodes can distinguish species of Indian mosquitoes (Diptera: Culicidae).

    Science.gov (United States)

    Kumar, N Pradeep; Rajavel, A R; Natarajan, R; Jambulingam, P

    2007-01-01

    Species identification of mosquitoes (Diptera: Culicidae) based on morphological characteristics remains often difficult in field-collected mosquito specimens in vector-borne disease surveillance programs. The use of DNA barcodes has been proposed recently as a tool for identification of the species in many diverse groups of animals. However, the efficacy of this tool for mosquitoes remains unexplored. Hence, a study was undertaken to construct DNA barcodes for several species of mosquitoes prevalent in India, which included major vector species. In total, 111 specimens of mosquitoes belonging to 15 genera, morphologically identified to be 63 species, were used. This number also included multiple specimens for 22 species. DNA barcode approach based on DNA sequences of mitochondrial cytochrome oxidase gene sequences could identify 62 species among these, in confirmation with the conventional taxonomy. However, two closely related species, Ochlerotatus portonovoensis (Tiwari & Hiriyan) and Ochlerotatus wardi (Reinert) could not be identified as separate species based on DNA barcode approach, their lineages indicating negligible genetic divergence (Kimura two-parameter genetic distance = 0.0043). PMID:17294914

  8. CCMR: How Mosquitoes Use Their Legs to Stabilize Flight

    Science.gov (United States)

    Reid, Candy

    2010-08-15

    Much can be learnt from insects, which, with only two flapping wings can perform maneuvers that produce both powerful forward speed like that of an airplane and hovering capabilities like those of a helicopter. With these things in mind, we study insects like the fruit fly and the mosquito. High speed cameras are used to film these insects performing maneuvers and their wing and body motions analyzed. Background work done by the Cornell Flight group sets up an avenue by which these subtle movements can be analyzed. Prior studies done on fruit flies show that they change the angle of their wings to produce changes in motion. Here, the flight of mosquitoes is examined. Upon examination, there was no sizeable correlation that indicated that mosquitoes use their legs to steer. Their legs were then removed and legless mosquito flight was analyzed. Legless mosquito flight was found to be quite stable with a noticeable oscillation in roll angle. The gravitational torque was found to be responsible for the period of oscillations, however, it was undeterminable as to how much of the damping that was observed was due to an active torque or a passive torque. Further analysis will be done with motion tracking to quantify these observations.

  9. Mosquito size and multiple transmission of avian malaria in the laboratory.

    Science.gov (United States)

    Kelly, R; Edman, J D

    1992-12-01

    Probing mosquitoes salivate before ingesting blood, and malaria sporozoites are transmitted during this phase of feeding. Large and small Aedes aegypti infected with Plasmodium gallinaceum were allowed to probe briefly on a series of 3 naive chicks. Large mosquitoes were more infective overall, but there was no difference in the ability of either size class to infect the first host. Large mosquitoes were more likely than small mosquitoes to infect more than one host during serial feeding. PMID:1474384

  10. Developmentally regulated infectivity of malaria sporozoites for mosquito salivary glands and the vertebrate host

    OpenAIRE

    1992-01-01

    Sporozoites are an invasive stage of the malaria parasite in both the mosquito vector and the vertebrate host. We developed an in vivo assay for mosquito salivary gland invasion by preparing Plasmodium gallinaceum sporozoites from infected Aedes aegypti mosquitoes under physiological conditions and inoculating them into uninfected female Ae. aegypti. Sporozoites from mature oocysts were isolated from mosquito abdomens 10 or 11 d after an infective blood meal. Salivary gland sporozoites were i...

  11. Satellite Microwave Remote Sensing for Environmental Modeling of Mosquito Population Dynamics

    OpenAIRE

    Chuang, Ting-wu; Henebry, Geoffrey M.; Kimball, John S.; Vanroekel-patton, Denise L.; Hildreth, Michael B.; Wimberly, Michael C.

    2012-01-01

    Environmental variability has important influences on mosquito life cycles and understanding the spatial and temporal patterns of mosquito populations is critical for mosquito control and vector-borne disease prevention. Meteorological data used for model-based predictions of mosquito abundance and life cycle dynamics are typically acquired from ground-based weather stations; however, data availability and completeness are often limited by sparse networks and resource availability. In contras...

  12. Mosquito-Host Interactions during and after an Outbreak of Equine Viral Encephalitis in Eastern Panama

    OpenAIRE

    Navia-gine, Wayra G.; Loaiza, Jose R.; Miller, Matthew J.

    2013-01-01

    Mosquito blood meals provide information about the feeding habits and host preference of potential arthropod-borne disease vectors. Although mosquito-borne diseases are ubiquitous in the Neotropics, few studies in this region have assessed patterns of mosquito-host interactions, especially during actual disease outbreaks. Based on collections made during and after an outbreak of equine viral encephalitis, we identified the source of 338 blood meals from 10 species of mosquitoes from Aruza Aba...

  13. Usage and Perceived Side Effects of Personal Protective Measures against Mosquitoes among Current Users in Delhi

    OpenAIRE

    Charu Kohli; Rajesh Kumar; G. S. Meena; Singh, M.M.; Jyotiranjan Sahoo; G. K. Ingle

    2014-01-01

    Background. Mosquito-borne diseases constitute an important cause of morbidity and mortality. The use of personal protective measures (PPM) like mats, bednets, screening, repellents, liquid vaporizers, mosquito coils, and so forth has been advocated as an effective tool in control of mosquito-borne diseases, but data about the safety profile of personal protective measures is still scarce. Objective. To study the usage and side effects of personal protective measures against mosquitoes among ...

  14. Transgenic malaria-resistant mosquitoes have a fitness advantage when feeding on Plasmodium-infected blood

    OpenAIRE

    Marrelli, Mauro T.; Li, Chaoyang; Rasgon, Jason L.; Jacobs-Lorena, Marcelo

    2007-01-01

    The introduction of genes that impair Plasmodium development into mosquito populations is a strategy being considered for malaria control. The effect of the transgene on mosquito fitness is a crucial parameter influencing the success of this approach. We have previously shown that anopheline mosquitoes expressing the SM1 peptide in the midgut lumen are impaired for transmission of Plasmodium berghei. Moreover, the transgenic mosquitoes had no noticeable fitness load compared with nontransgeni...

  15. Evaluation of mosquitoes, Aedes vexans, as biological vectors of porcine reproductive and respiratory syndrome virus

    OpenAIRE

    Otake, Satoshi; Dee, Scott A.; Moon, Roger D.; Rossow, Kurt D.; Trincado, Carlos; Pijoan, Carlos

    2003-01-01

    The objective of this study was to determine whether mosquitoes, Aedes vexans (Meigen), could serve as biological vectors of porcine reproductive and respiratory syndrome virus (PRRSV). Specifically, the study assessed the duration of viability and the site of PRRSV within mosquitoes, and evaluated whether PRRSV could be transmitted to a susceptible pig by mosquitoes following a 7- to 14-day incubation period after feeding on an infected pig. For the first experiment, a total of 100 mosquitoe...

  16. Quantitative Dynamics of Plasmodium yoelii Sporozoite Transmission by Infected Anopheline Mosquitoes

    OpenAIRE

    Medica, Darcy L.; Sinnis, Photini

    2005-01-01

    Malaria transmission begins with the injection of Plasmodium sporozoites into the skin of a vertebrate host by infected anopheline mosquitoes. Although the size of the sporozoite inoculum likely affects the course of the disease, the number of sporozoites injected by infected mosquitoes has not been determined in vivo. Using a quantitative PCR assay, we determined the number of sporozoites injected into mice by single mosquitoes. Analysis of 59 mosquito feedings showed that a single infected ...

  17. Low- and High-Tech Approaches to Control Plasmodium Parasite Transmission by Anopheles Mosquitoes

    OpenAIRE

    Cirimotich, Chris M; April M. Clayton; George Dimopoulos

    2011-01-01

    Current efforts have proven inadequate to stop the transmission of Plasmodium parasites, and hence the spread of malaria, by Anopheles mosquitoes. Therefore, a novel arsenal of strategies for inhibiting Plasmodium infection of mosquitoes is urgently needed. In this paper, we summarize research on two approaches to malaria control, a low-tech strategy based on parasite inhibition by the mosquito's natural microflora, and a high-tech strategy using genetic modification of mosquitoes that render...

  18. Stability of St. Louis encephalitis viral antigen detected by enzyme immunoassay in infected mosquitoes.

    OpenAIRE

    Tsai, T. F.; Happ, C. M.; Bolin, R A; Montoya, M; Campos, E.; Francy, D B; Hawkes, R. A.; Roehrig, J T

    1988-01-01

    The use of enzyme immunoassay to detect St. Louis encephalitis (SLE) viral antigen in vector mosquitoes enhances the effectiveness of surveillance because infected mosquitoes can be identified more rapidly than with conventional virus isolation systems and because it is a simple and accessible procedure. Infectivity among mosquitoes experimentally infected with SLE virus was lost within 24 h after the mosquitoes were stored at 27 degrees C and 80% relative humidity; however, viral antigen rem...

  19. Mosquito Heparan Sulfate and Its Potential Role in Malaria Infection and Transmission*

    OpenAIRE

    Sinnis, Photini; Coppi, Alida; Toida, Toshihiko; Toyoda, Hidenao; Kinoshita-toyoda, Akiko; Xie, Jin; Kemp, Melissa M.; Linhardt, Robert J.

    2007-01-01

    Heparan sulfate has been isolated for the first time from the mosquito Anopheles stephensi, a known vector for Plasmodium parasites, the causative agents of malaria. Chondroitin sulfate, but not dermatan sulfate or hyaluronan, was also present in the mosquito. The glycosaminoglycans were isolated, from salivary glands and midguts of the mosquito in quantities sufficient for disaccharide microanalysis. Both of these organs are invaded at different stages of the Plasmodium life cycle. Mosquito ...

  20. Mosquito and Drosophila entomobirnaviruses suppress dsRNA- and siRNA-induced RNAi

    OpenAIRE

    van Cleef, Koen W. R.; van Mierlo, Joël T.; Miesen, Pascal; Gijs J. Overheul; Fros, Jelke J.; Schuster, Susan; Marklewitz, Marco; Pijlman, Gorben P.; Junglen, Sandra; van Rij, Ronald P.

    2014-01-01

    RNA interference (RNAi) is a crucial antiviral defense mechanism in insects, including the major mosquito species that transmit important human viruses. To counteract the potent antiviral RNAi pathway, insect viruses encode RNAi suppressors. However, whether mosquito-specific viruses suppress RNAi remains unclear. We therefore set out to study RNAi suppression by Culex Y virus (CYV), a mosquito-specific virus of the Birnaviridae family that was recently isolated from Culex pipiens mosquitoes....

  1. Behavioural and insecticidal effects of organophosphate-, carbamate- and pyrethroid-treated mosquito nets against African malaria vectors.

    Science.gov (United States)

    Malima, R C; Oxborough, R M; Tungu, P K; Maxwell, C; Lyimo, I; Mwingira, V; Mosha, F W; Matowo, J; Magesa, S M; Rowland, M W

    2009-12-01

    Three insecticides - the pyrethroid deltamethrin, the carbamate carbosulfan and the organophosphate chlorpyrifos-methyl - were tested on mosquito nets in experimental huts to determine their potential for introduction as malaria control measures. Their behavioural effects and efficacy were examined in Anopheles gambiae Giles s.s. (Diptera: Culicidae) and Anopheles funestus Giles s.s. in Muheza, Tanzania, and in Anopheles arabiensis Patton and Culex quinquefasciatus Say in Moshi, Tanzania. A standardized dosage of 25 mg/m(2) plus high dosages of carbosulfan (50 mg/m(2), 100 mg/m(2) and 200 mg/m(2)) and chlorpyrifos-methyl (100 mg/m(2)) were used to compare the three types of insecticide. At 25 mg/m(2), the rank order of the insecticides for insecticide-induced mortality in wild An. gambiae and An. funestus was, respectively, carbosulfan (88%, 86%) > deltamethrin (79%, 78%) > chlorpyrifos-methyl (35%, 53%). The rank order of the insecticides for blood-feeding inhibition (reduction in the number of blood-fed mosquitoes compared with control) in wild An. gambiae and An. funestus was deltamethrin > chlorpyrifos-methyl > carbosulfan. Carbosulfan was particularly toxic to endophilic anophelines at 200 mg/m(2), killing 100% of An. gambiae and 98% of An. funestus that entered the huts. It was less effective against the more exophilic An. arabiensis (67% mortality) and carbamate-resistant Cx quinquefasciatus (36% mortality). Carbosulfan deterred anophelines from entering huts, but did not deter carbamate-resistant Cx quinquefasciatus. Deltamethrin reduced the proportion of insects engaged in blood-feeding, probably as a consequence of contact irritancy, whereas carbosulfan seemed to provide personal protection through deterred entry or perhaps a spatial repellent action. Any deployment of carbosulfan as an individual treatment on nets should be carried out on a large scale to reduce the risk of diverting mosquitoes to unprotected individuals. Chlorpyrifos-methyl was inferior to deltamethrin in terms of mortality and blood-feeding inhibition and would be better deployed on a net in combination with a pyrethroid to control insecticide-resistant mosquitoes. PMID:19941597

  2. Geometry of Killing spinors in neutral signature

    CERN Document Server

    Klemm, Dietmar

    2015-01-01

    We classify the supersymmetric solutions of minimal $N=2$ gauged supergravity in four dimensions with neutral signature. They are distinguished according to the sign of the cosmological constant and whether the vector field constructed as a bilinear of the Killing spinor is null or non-null. In neutral signature the bilinear vector field can be spacelike, which is a new feature not arising in Lorentzian signature. In the $\\Lambda0$ non-null case, the manifold is a fibration over a Lorentzian Gauduchon-Tod base space. Finally, in the $\\Lambda>0$ null class, the metric is contained in the Kundt family, and it turns out that the holonomy is reduced to ${\\rm Sim}(1)\\times{\\rm Sim}(1)$. There appear no self-dual solutions in the null class for either sign of the cosmological constant.

  3. Characterization of Anopheles gambiae (African Malaria Mosquito) Ferritin and the Effect of Iron on Intracellular Localization in Mosquito Cells.

    Science.gov (United States)

    Geiser, Dawn L; Conley, Zachary R; Elliott, Jamie L; Mayo, Jonathan J; Winzerling, Joy J

    2015-01-01

    Ferritin is a 24-subunit molecule, made up of heavy chain (HC) and light chain (LC) subunits, which stores and controls the release of dietary iron in mammals, plants, and insects. In mosquitoes, dietary iron taken in a bloodmeal is stored inside ferritin. Our previous work has demonstrated the transport of dietary iron to the ovaries via ferritin during oogenesis. We evaluated the localization of ferritin subunits inside CCL-125 [Aedes aegypti Linnaeus (Diptera: Culicidae), yellow fever mosquito] and 4a3b [Anopheles gambiae Giles (Diptera: Culicidae), African malaria mosquito] cells under various iron treatment conditions to further elucidate the regulation of iron metabolism in these important disease vectors and to observe the dynamics of the intracellular ferritin subunits following iron administration. Deconvolution microscopy captured 3D fluorescent images of iron-treated mosquito cells to visualize the ferritin HC and LC homologue subunits (HCH and LCH, respectively) in multiple focal planes. Fluorescent probes were used to illuminate cell organelles (i.e., Golgi apparatus, lysosomes, and nuclei) while secondary probes for specific ferritin subunits demonstrated abundance and co-localization within organelles. These images will help to develop a model for the biochemical regulation of ferritin under conditions of iron exposure, and to advance novel hypotheses for the crucial role of iron in mosquito vectors. PMID:26078302

  4. Field incidence of mosquito pathogens and parasites in central Alberta.

    Science.gov (United States)

    Goettel, M S

    1987-06-01

    Ten pools and ponds were monitored on a weekly basis for presence of mosquito pathogens and parasites over a three year period near Edmonton, Alberta. Acari, fungi, Microsporidia and Peritrichida were found associated with mosquitoes. Percentage of collections with pathogens and parasites (prevalence) followed by the mean percentage infection within the samples, in parentheses (estimated % incidence) for the three year period were as follows: Coelomomyces psorophorae var. psorophorae 0.9(0.01-0.02), Culicinomyces clavisporus 1.2(0.09-0.2), Saprolegniales 50.1(15), Smittium sp. 23.0(4), Microsporidia 10.9(0.6-1.4), Peritrichida 43.4(30) and Acari 3.2(0.04). The high incidence of Saprolegniales may be a result of attack on stressed individuals under laboratory conditions. Several host and country records are reported. It is concluded that pathogens and parasites generally had little effect on the mosquito populations. PMID:2904946

  5. A male-determining factor in the mosquito Aedes aegypti.

    Science.gov (United States)

    Hall, Andrew Brantley; Basu, Sanjay; Jiang, Xiaofang; Qi, Yumin; Timoshevskiy, Vladimir A; Biedler, James K; Sharakhova, Maria V; Elahi, Rubayet; Anderson, Michelle A E; Chen, Xiao-Guang; Sharakhov, Igor V; Adelman, Zach N; Tu, Zhijian

    2015-06-12

    Sex determination in the mosquito Aedes aegypti is governed by a dominant male-determining factor (M factor) located within a Y chromosome-like region called the M locus. Here, we show that an M-locus gene, Nix, functions as an M factor in A. aegypti. Nix exhibits persistent M linkage and early embryonic expression, two characteristics required of an M factor. Nix knockout with clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 resulted in largely feminized genetic males and the production of female isoforms of two key regulators of sexual differentiation: doublesex and fruitless. Ectopic expression of Nix resulted in genetic females with nearly complete male genitalia. Thus, Nix is both required and sufficient to initiate male development. This study provides a foundation for mosquito control strategies that convert female mosquitoes into harmless males. PMID:25999371

  6. Periodic dynamic systems for infected hosts and mosquitoes

    Directory of Open Access Journals (Sweden)

    Oliva W. M.

    1996-01-01

    Full Text Available A mathematical model for the purpose of analysing the dynamic of the populations of infected hosts anf infected mosquitoes when the populations of mosquitoes are periodic in time is here presented. By the computation of a parameter lambda (the spectral radius of a certain monodromy matrix one can state that either the infection peters out naturally (lambda 1 the infection becomes endemic. The model generalizes previous models for malaria by considering the case of periodic coefficients; it is also a variation of that for gonorrhea. The main motivation for the consideration of this present model was the recent studies on mosquitoes at an experimental rice irrigation system, in the South-Eastern region of Brazil.

  7. Statics and dynamics of malaria infection in Anopheles mosquitoes

    Directory of Open Access Journals (Sweden)

    Ellis McKenzie F

    2004-06-01

    Full Text Available Abstract The classic formulae in malaria epidemiology are reviewed that relate entomological parameters to malaria transmission, including mosquito survivorship and age-at-infection, the stability index (S, the human blood index (HBI, proportion of infected mosquitoes, the sporozoite rate, the entomological inoculation rate (EIR, vectorial capacity (C and the basic reproductive number (R0. The synthesis emphasizes the relationships among classic formulae and reformulates a simple dynamic model for the proportion of infected humans. The classic formulae are related to formulae from cyclical feeding models, and some inconsistencies are noted. The classic formulae are used to to illustrate how malaria control reduces malaria transmission and show that increased mosquito mortality has an effect even larger than was proposed by Macdonald in the 1950's.

  8. Adult mosquitoes parasitized by larval water mites in Pennsylvania.

    Science.gov (United States)

    Kirkhoff, Christopher J; Simmons, Thomas W; Hutchinson, Michael

    2013-02-01

    A survey of water mite larvae parasitizing adult mosquitoes was conducted throughout Pennsylvania. In total, 929,873 individuals and 46 species of mosquitoes were collected from 6,499 sites, and mites were examined from a subset of the parasitized mosquitoes. From 282 of the sites, 1,836 mosquitoes were parasitized by 4,769 mites, with a mean intensity of 2.6, ranging from 1 to 31. Twenty-one species of mosquitoes representing Aedes, Anopheles, Coquillettidia, Culex, Ochlerotatus, Orthopodomyia, and Psorophora were parasitized by 1 Parathyas sp., 7 Arrenurus spp., and 7 Arrenurus morphotypes. All mite species are documented from Pennsylvania for the first time. The largest numbers of hosts were Coquillettidia perturbans and Ochlerotatus trivittatus, and of parasites were Arrenurus danbyensis and Parathyas barbigera. Aedes spp., Ochlerotatus spp., and Psorophora ferox were mostly parasitized by P. barbigera, Anopheles spp. and Cq. perturbans mostly by Arrenurus spp., and Culex spp. by both P. barbigera and Arrenurus spp. Thirty-three different associations were observed, and 17 of these are new records. Parasitism of individual mosquitoes by more than 1 mite species was rare. Most P. barbigera individuals were attached on the pre-abdominal region of their hosts, and, when not in this position, they were attached anterior on the thorax, and less commonly on the cervix or abdomen. Most A. danbyensis and Arrenurus delawarensis individuals were attached to the cervix of Cq. perturbans. Arrenurus danbyensis on Cq. perturbans had mean and maximum intensities of 2.8 and 31, and showed a clear trend in attachment site distribution, with sequential progression from head to abdomen. PMID:22924904

  9. Plasmodium knowlesi in humans, macaques and mosquitoes in peninsular Malaysia

    Directory of Open Access Journals (Sweden)

    NorParina Ismail

    2008-08-01

    Full Text Available Abstract Background Since a large focus of human infection with Plasmodium knowlesi, a simian malaria parasite naturally found in long-tailed and pig tailed macaques, was reported in Sarawak, Malaysian Borneo, it was pertinent to study the situation in peninsular Malaysia. A study was thus initiated to screen human cases of Plasmodium malariae using molecular techniques, to determine the presence of P. knowlesi in non- human primates and to elucidate its vectors. Methods Nested polymerase chain reaction (PCR was used to identify all Plasmodium species present in the human blood samples sent to the Parasitology laboratory of Institute for Medical Research. At the same time, non-human primates were also screened for malaria parasites and nested PCR was carried out to determine the presence of P. knowlesi. Mosquitoes were collected from Pahang by human landing collection and monkey-baited-traps situated on three different levels. All mosquitoes were identified and salivary glands and midguts of anopheline mosquitoes were dissected to determine the presence of malaria parasites and nested PCR was carried out on positive glands. Sequencing of the csp genes were carried on P. knowlesi samples from humans, monkeys and mosquitoes, positive by PCR. Results and Discussion Plasmodium knowlesi was detected in 77 (69.37% of the 111 human samples, 10 (6.90% of the 145 monkey blood and in 2 (1.7% Anopheles cracens. Sequence of the csp gene clustered with other P. knowlesi isolates. Conclusion Human infection with Plasmodium knowlesi is occurring in most states of peninsular Malaysia. An. cracens is the main vector. Economic exploitation of the forest is perhaps bringing monkeys, mosquitoes and humans into increased contact. A single bite from a mosquito infected with P. knowlesi is sufficient to introduce the parasite to humans. Thus, this zoonotic transmission has to be considered in the future planning of malaria control.

  10. Kinetics of killing Listeria monocytogenes by macrophages: rapid killing accompanying phagocytosis

    International Nuclear Information System (INIS)

    The kinetics of bactericidal activity of activated macrophages can be precisely described by a mathematical model in which phagocytosis, killing, digestion, and release of degraded bacterial material are considered to occur continuously. To gain a better understanding of these events, I have determined the period of time between first contact of bacteria with macrophages and the onset of killing. Activated rat peritoneal macrophages were incubated for various times up to 15 min with Listeria monocytogenes previously labeled with 3H-thymidine and the unassociated bacteria removed by two centrifugations through a density interface. Both cell-associated radioactivity and cell-associated viable bacteria, determined as colony forming units after sonication of the cell pellet, increased with time of incubation. However, the specific viability of these bacteria, expressed as the ratio of number of viable bacteria per unit radioactivity declined with time, as an approximate inverse exponential, after a lag period of 2.9 +/- 0.8 min. Evidence is given that other possible causes for this decline in specific viability, other than death of the bacteria, such as preferential ingestion of dead Listeria, clumping of bacteria, variations in autolytic activity, or release of Listericidins are unlikely. I conclude therefore that activated macrophages kill Listeria approximately 3 min after the cell and the bacterium first make contactt

  11. Otters Lutra lutra killing Mountain Hares Lepus timidus

    Directory of Open Access Journals (Sweden)

    Conroy J.

    2000-04-01

    Full Text Available During the winter, otter Lutra lutra were found to kill mountain hares Lepus timidus in the Scottish highlands. The possible method of killing is discussed. Hares and other mammals are an important part of otter' diet during winter.

  12. Dimensional reduction in space-times admitting killing vectors

    International Nuclear Information System (INIS)

    We present a systematic method for performing dimensional reduction on theories constructed in (d + n)-dimensional space-times with torsion, which admit n Killing vectors. For one and two commuting Killing vectors, the field content of the corresponding (d + 1)- and (d + 2)-dimensional theories is completely worked out. (orig.)

  13. Killing of Bacteria by Copper Surfaces Involves Dissolved Copper?

    OpenAIRE

    Molteni, Cristina; Abicht, Helge K.; Solioz, Marc

    2010-01-01

    Bacteria are rapidly killed on copper surfaces. However, the mechanism of this process remains unclear. Using Enterococcus hirae, the effect of inactivation of copper homeostatic genes and of medium compositions on survival and copper dissolution was tested. The results support a role for dissolved copper ions in killing.

  14. PDE5 Inhibitors Enhance Celecoxib Killing in Multiple Tumor Types

    Science.gov (United States)

    BOOTH, LAURENCE; ROBERTS, JANE L.; CRUICKSHANKS, NICHOLA; TAVALLAI, SEYEDMEHRAD; WEBB, TIMOTHY; SAMUEL, PETER; CONLEY, ADAM; BINION, BRITTANY; YOUNG, HAROLD F.; POKLEPOVIC, ANDREW; SPIEGEL, SARAH; DENT, PAUL

    2015-01-01

    The present studies determined whether clinically relevant phosphodiesterase 5 (PDE5) inhibitors interacted with a clinically relevant NSAID, celecoxib, to kill tumor cells. Celecoxib and PDE5 inhibitors interacted in a greater than additive fashion to kill multiple tumor cell types. Celecoxib and sildenafil killed ex vivo primary human glioma cells as well as their associated activated microglia. Knock down of PDE5 recapitulated the effects of PDE5 inhibitor treatment; the nitric oxide synthase inhibitor L-NAME suppressed drug combination toxicity. The effects of celecoxib were COX2 independent. Over-expression of c-FLIP-s or knock down of CD95/FADD significantly reduced killing by the drug combination. CD95 activation was dependent on nitric oxide and ceramide signaling. CD95 signaling activated the JNK pathway and inhibition of JNK suppressed cell killing. The drug combination inactivated mTOR and increased the levels of autophagy and knock down of Beclin1 or ATG5 strongly suppressed killing by the drug combination. The drug combination caused an ER stress response; knock down of IRE1?/XBP1 enhanced killing whereas knock down of eIF2?/ATF4/CHOP suppressed killing. Sildenafil and celecoxib treatment suppressed the growth of mammary tumors in vivo. Collectively our data demonstrate that clinically achievable concentrations of celecoxib and sildenafil have the potential to be a new therapeutic approach for cancer. PMID:25303541

  15. PDE5 inhibitors enhance celecoxib killing in multiple tumor types.

    Science.gov (United States)

    Booth, Laurence; Roberts, Jane L; Cruickshanks, Nichola; Tavallai, Seyedmehrad; Webb, Timothy; Samuel, Peter; Conley, Adam; Binion, Brittany; Young, Harold F; Poklepovic, Andrew; Spiegel, Sarah; Dent, Paul

    2015-05-01

    The present studies determined whether clinically relevant phosphodiesterase 5 (PDE5) inhibitors interacted with a clinically relevant NSAID, celecoxib, to kill tumor cells. Celecoxib and PDE5 inhibitors interacted in a greater than additive fashion to kill multiple tumor cell types. Celecoxib and sildenafil killed ex vivo primary human glioma cells as well as their associated activated microglia. Knock down of PDE5 recapitulated the effects of PDE5 inhibitor treatment; the nitric oxide synthase inhibitor L-NAME suppressed drug combination toxicity. The effects of celecoxib were COX2 independent. Over-expression of c-FLIP-s or knock down of CD95/FADD significantly reduced killing by the drug combination. CD95 activation was dependent on nitric oxide and ceramide signaling. CD95 signaling activated the JNK pathway and inhibition of JNK suppressed cell killing. The drug combination inactivated mTOR and increased the levels of autophagy and knock down of Beclin1 or ATG5 strongly suppressed killing by the drug combination. The drug combination caused an ER stress response; knock down of IRE1?/XBP1 enhanced killing whereas knock down of eIF2?/ATF4/CHOP suppressed killing. Sildenafil and celecoxib treatment suppressed the growth of mammary tumors in vivo. Collectively our data demonstrate that clinically achievable concentrations of celecoxib and sildenafil have the potential to be a new therapeutic approach for cancer. PMID:25303541

  16. Mechanisms of Dendritic Cell Lysosomal Killing of Cryptococcus

    Science.gov (United States)

    Hole, Camaron R.; Bui, Hoang; Wormley, Floyd L.; Wozniak, Karen L.

    2012-10-01

    Cryptococcus neoformans is an opportunistic pulmonary fungal pathogen that disseminates to the CNS causing fatal meningitis in immunocompromised patients. Dendritic cells (DCs) phagocytose C. neoformans following inhalation. Following uptake, cryptococci translocate to the DC lysosomal compartment and are killed by oxidative and non-oxidative mechanisms. DC lysosomal extracts kill cryptococci in vitro; however, the means of antifungal activity remain unknown. Our studies determined non-oxidative antifungal activity by DC lysosomal extract. We examined DC lysosomal killing of cryptococcal strains, anti-fungal activity of purified lysosomal enzymes, and mechanisms of killing against C. neoformans. Results confirmed DC lysosome fungicidal activity against all cryptococcal serotypes. Purified lysosomal enzymes, specifically cathepsin B, inhibited cryptococcal growth. Interestingly, cathepsin B combined with its enzymatic inhibitors led to enhanced cryptococcal killing. Electron microscopy revealed structural changes and ruptured cryptococcal cell walls following treatment. Finally, additional studies demonstrated that osmotic lysis was responsible for cryptococcal death.

  17. Host-feeding patterns of mosquitoes (Diptera: Culicidae) from central Panama.

    Science.gov (United States)

    Christensen, H A; de Vasquez, A M; Boreham, M M

    1996-08-01

    A 10-year study of blood meal identification in mosquitoes collected at numerous sites over several ecosystems in central Panama was conducted from 1977 to 1987. The hosts for 4,391 mosquito blood meals, representing 30 species, were identified to the family level of specificity in most instances. The degree that individual mosquitoes had fed on animals of different classes and families within these classes was determined. Multiple feeding among several mosquito species was documented. The relationship between reservoir hosts of endemic arboviruses and a number of known and potential mosquito vectors was demonstrated as a result of the blood meal identifications. PMID:8780461

  18. Mosquito ingestion of antibodies against mosquito midgut microbiota improves conversion of ookinetes to oocysts for Plasmodium falciparum, but not P. yoelii

    OpenAIRE

    Noden, Bruce H.; Vaughan, Jefferson A.; Pumpuni, Charles B.; Beier, John C.

    2011-01-01

    The mosquito midgut is a site of complex interactions between the mosquito, the malaria parasite and the resident bacterial flora. In laboratory experiments, we observed significant enhancement of Plasmodium falciparum oocyst production when Anopheles gambiae (Diptera: Culicidae) mosquitoes were membrane-fed on infected blood containing gametocytes from in vitro cultures mixed with sera from rabbits immunized with A. gambiae midguts. To identify specific mechanisms, we evaluated whether the i...

  19. Integrating the Public in Mosquito Management: Active Education by Community Peers Can Lead to Significant Reduction in Peridomestic Container Mosquito Habitats

    OpenAIRE

    Healy, Kristen; Hamilton, George; Crepeau, Taryn; Healy, Sean; Unlu, Isik; Farajollahi, Ary; FONSECA, DINA M.

    2014-01-01

    Mosquito species that utilize peridomestic containers for immature development are commonly aggressive human biters, and because they often reach high abundance, create significant nuisance. One of these species, the Asian tiger mosquito Aedes albopictus, is an important vector of emerging infectious diseases, such as dengue, chikungunya, and Zika fevers. Integrated mosquito management (IMM) of Ae. albopictus is particularly difficult because it requires access to private yards in urban and s...

  20. Does Japanese encephalitis virus share the same cellular receptor with other mosquito-borne flaviviruses on the C6/36 mosquito cells?

    OpenAIRE

    Song Jianhua; Zhang Wei; Ding Tianbing; Ren Junping; Ma Wenyu

    2007-01-01

    Abstract Japanese encephalitis virus (JEV) is a member of mosquito-borne Flaviviridae. To date, the mechanisms of the early events of JEV infection remain poorly understood, and the cellular receptors are unidentified. There are evidences that the structure of the virus attachment proteins (VAP), envelope glycoprotein of mosquito-borne flaviviruses is very similar, and the vector-virus interaction of mosquito-borne flaviviruses is also very similar. Based on the studies previously demonstrate...

  1. A global assembly of adult female mosquito mark-release-recapture data to inform the control of mosquito-borne pathogens

    OpenAIRE

    Guerra, C.A.; Reiner Jr, R.C.; Perkins, T.A.; Lindsay, S.W.; Midega, J.T.; Brady, O.J.; Barker, C.M.; Reisen, W. K.; Harrington, L.C.; Takken, W.; Kitron, U.; Lloyd, A.L.; Hay, S I; Scott, T.W.; Smith, D. L.

    2014-01-01

    Background Pathogen transmission by mosquitos is known to be highly sensitive to mosquito bionomic parameters. Mosquito mark-release-recapture (MMRR) experiments are a standard method for estimating such parameters including dispersal, population size and density, survival, blood feeding frequency and blood meal host preferences. Methods We assembled a comprehensive database describing adult female MMRR experiments. Bibliographic searches were used to build a digital library of MMRR studies a...

  2. Francisella tularensis Subspecies holarctica Occurs in Swedish Mosquitoes, Persists Through the Developmental Stages of Laboratory-Infected Mosquitoes and Is Transmissible During Blood Feeding

    OpenAIRE

    Thelaus, J.; Andersson, A.; Broman, T.; Backman, S.; Granberg, M.; Karlsson, L.; Kuoppa, K.; Larsson, E.; Lundmark, E; Lundström, Jan O.; Mathisen, P.; Naslund, J; Schäfer, M.; Wahab, T.; Forsman, M.

    2014-01-01

    In Sweden, mosquitoes are considered the major vectors of the bacterium Francisella tularensis subsp. holarctica, which causes tularaemia. The aim of this study was to investigate whether mosquitoes acquire the bacterium as aquatic larvae and transmit the disease as adults. Mosquitoes sampled in a Swedish area where tularaemia is endemic (A-rebro) were positive for the presence of F. tularensis deoxyribonucleic acid throughout the summer. Presence of the clinically relevant F. tularensis subs...

  3. A Neuron-Specific Antiviral Mechanism Prevents Lethal Flaviviral Infection of Mosquitoes

    Science.gov (United States)

    Xiao, Xiaoping; Zhang, Rudian; Pang, Xiaojing; Liang, Guodong; Wang, Penghua; Cheng, Gong

    2015-01-01

    Mosquitoes are natural vectors for many etiologic agents of human viral diseases. Mosquito-borne flaviviruses can persistently infect the mosquito central nervous system without causing dramatic pathology or influencing the mosquito behavior and lifespan. The mechanism by which the mosquito nervous system resists flaviviral infection is still largely unknown. Here we report that an Aedes aegypti homologue of the neural factor Hikaru genki (AaHig) efficiently restricts flavivirus infection of the central nervous system. AaHig was predominantly expressed in the mosquito nervous system and localized to the plasma membrane of neural cells. Functional blockade of AaHig enhanced Dengue virus (DENV) and Japanese encephalitis virus (JEV), but not Sindbis virus (SINV), replication in mosquito heads and consequently caused neural apoptosis and a dramatic reduction in the mosquito lifespan. Consistently, delivery of recombinant AaHig to mosquitoes reduced viral infection. Furthermore, the membrane-localized AaHig directly interfaced with a highly conserved motif in the surface envelope proteins of DENV and JEV, and consequently interrupted endocytic viral entry into mosquito cells. Loss of either plasma membrane targeting or virion-binding ability rendered AaHig nonfunctional. Interestingly, Culex pipien pallens Hig also demonstrated a prominent anti-flavivirus activity, suggesting a functionally conserved function for Hig. Our results demonstrate that an evolutionarily conserved antiviral mechanism prevents lethal flaviviral infection of the central nervous system in mosquitoes, and thus may facilitate flaviviral transmission in nature. PMID:25915054

  4. A neuron-specific antiviral mechanism prevents lethal flaviviral infection of mosquitoes.

    Science.gov (United States)

    Xiao, Xiaoping; Zhang, Rudian; Pang, Xiaojing; Liang, Guodong; Wang, Penghua; Cheng, Gong

    2015-04-01

    Mosquitoes are natural vectors for many etiologic agents of human viral diseases. Mosquito-borne flaviviruses can persistently infect the mosquito central nervous system without causing dramatic pathology or influencing the mosquito behavior and lifespan. The mechanism by which the mosquito nervous system resists flaviviral infection is still largely unknown. Here we report that an Aedes aegypti homologue of the neural factor Hikaru genki (AaHig) efficiently restricts flavivirus infection of the central nervous system. AaHig was predominantly expressed in the mosquito nervous system and localized to the plasma membrane of neural cells. Functional blockade of AaHig enhanced Dengue virus (DENV) and Japanese encephalitis virus (JEV), but not Sindbis virus (SINV), replication in mosquito heads and consequently caused neural apoptosis and a dramatic reduction in the mosquito lifespan. Consistently, delivery of recombinant AaHig to mosquitoes reduced viral infection. Furthermore, the membrane-localized AaHig directly interfaced with a highly conserved motif in the surface envelope proteins of DENV and JEV, and consequently interrupted endocytic viral entry into mosquito cells. Loss of either plasma membrane targeting or virion-binding ability rendered AaHig nonfunctional. Interestingly, Culex pipien pallens Hig also demonstrated a prominent anti-flavivirus activity, suggesting a functionally conserved function for Hig. Our results demonstrate that an evolutionarily conserved antiviral mechanism prevents lethal flaviviral infection of the central nervous system in mosquitoes, and thus may facilitate flaviviral transmission in nature. PMID:25915054

  5. Cultured skin microbiota attracts malaria mosquitoes

    Directory of Open Access Journals (Sweden)

    Takken Willem

    2009-12-01

    Full Text Available Abstract Background Host-seeking of the African malaria mosquito, Anopheles gambiae sensu stricto, is guided by human odours. The precise nature of the odours, and the composition of attractive blends of volatiles, remains largely unknown. Skin microbiota plays an important role in the production of human body odours. It is hypothesized that host attractiveness and selection of An. gambiae is affected by the species composition, density, and metabolic activity of the skin microbiota. A study is presented in which the production and constituency of volatile organic compounds (VOCs by human skin microbiota is examined and the behavioural responses of An. gambiae to VOCs from skin microbiota are investigated. Methods Blood agar plates incubated with skin microbiota from human feet or with a reference strain of Staphylococcus epidermidis were tested for their attractiveness to An. gambiae in olfactometer bioassays and indoor trapping experiments. Entrained air collected from blood agar plates incubated with natural skin microbiota or with S. epidermidis were analysed using GC-MS. A synthetic blend of the compounds identified was tested for its attractiveness to An. gambiae. Behavioural data were analysed by a ?2-test and GLM. GC-MS results were analysed by fitting an exponential regression line to test the effect of the concentration of bacteria. Results More An. gambiae were caught with blood agar plates incubated with skin bacteria than with sterile blood agar plates, with a significant effect of incubation time and dilution of the skin microbiota. When bacteria from the feet of four other volunteers were tested, similar effects were found. Fourteen putative attractants were found in the headspace of the skin bacteria. A synthetic blend of 10 of these was attractive to An. gambiae. Conclusions The discovery that volatiles produced by human skin microorganisms in vitro mediate An. gambiae host-seeking behaviour creates new opportunities for the development of odour-baited trapping systems. Additionally, identification of bacterial volatiles provides a new method to develop synthetic blends, attractive to An. gambiae and possibly other anthropophilic disease vectors.

  6. Wolbachia infection does not alter attraction of the mosquito Aedes (Stegomyia) aegypti to human odours.

    Science.gov (United States)

    Turley, A P; Smallegange, R C; Takken, W; Zalucki, M P; O'Neill, S L; McGraw, E A

    2014-12-01

    The insect endosymbiont Wolbachia pipientis (Rickettsiales: Rickettsiaceae) is undergoing field trials around the world to determine if it can reduce transmission of dengue virus from the mosquito Stegomyia aegypti to humans. Two different Wolbachia strains have been released to date. The primary effect of the wMel strain is pathogen protection whereby infection with the symbiont limits replication of dengue virus inside the mosquito. A second strain, wMelPop, induces pathogen protection, reduces the adult mosquito lifespan and decreases blood feeding success in mosquitoes after 15 days of age. Here we test whether Wolbachia infection affects mosquito attraction to host odours in adults aged 5 and 15 days. We found no evidence of reduced odour attraction of mosquitoes, even for those infected with the more virulent wMelPop. This bodes well for fitness and competitiveness in the field given that the mosquitoes must find hosts to reproduce for the biocontrol method to succeed. PMID:24797695

  7. Mouse oocyte killing by neutrons: target considerations

    International Nuclear Information System (INIS)

    Highly radiosensitive primordial mouse oocytes, the principal cells at genetic risk in the female, have been studied using 0.43 MeV neutrons. Analysis of the survival curve (D37 = 0.055 Gy) indicates that the diameter of the radiosensitive target (assumed spherical and of unit density) is larger than that of the nucleus but not of the oocyte, implicating a non-nuclear but sub-cellular target. This is consistent with results from the 3H-thymidine incorporated in DNA. Efforts to identify the extraordinarily radiosensitive lethality target in these primordial oocytes suggest it is the plasma membrane. Monte Carlo calculations for 0.43 MeV neutrons show that at the D37 only a single proton recoil will traverse the plasma membrane, consistent with the observed exponential survival curve. A highly sensitive non-DNA target for mouse oocyte killing may importantly influence interpretations of genetic mutation data from mice and their use in estimating genetic risk in humans. (author)

  8. Novel innate cancer killing activity in humans

    Directory of Open Access Journals (Sweden)

    Lovato James

    2011-08-01

    Full Text Available Abstract Background In this study, we pilot tested an in vitro assay of cancer killing activity (CKA in circulating leukocytes of 22 cancer cases and 25 healthy controls. Methods Using a human cervical cancer cell line, HeLa, as target cells, we compared the CKA in circulating leukocytes, as effector cells, of cancer cases and controls. The CKA was normalized as percentages of total target cells during selected periods of incubation time and at selected effector/target cell ratios in comparison to no-effector-cell controls. Results Our results showed that CKA similar to that of our previous study of SR/CR mice was present in human circulating leukocytes but at profoundly different levels in individuals. Overall, males have a significantly higher CKA than females. The CKA levels in cancer cases were lower than that in healthy controls (mean ± SD: 36.97 ± 21.39 vs. 46.28 ± 27.22. Below-median CKA was significantly associated with case status (odds ratio = 4.36; 95% Confidence Interval = 1.06, 17.88 after adjustment of gender and race. Conclusions In freshly isolated human leukocytes, we were able to detect an apparent CKA in a similar manner to that of cancer-resistant SR/CR mice. The finding of CKA at lower levels in cancer patients suggests the possibility that it may be of a consequence of genetic, physiological, or pathological conditions, pending future studies with larger sample size.

  9. Mouse oocyte killing by neutrons: target considerations

    International Nuclear Information System (INIS)

    Highly radiosensitive primordial mouse oocytes, the principal cells at genetic risk in the female, have been studied using 0.43-MeV neutrons. Analysis of the survival curve (D37 = 0.055 Gy) indicates that the diameter of the radiosensitive target (assumed spherical and of unit density) is larger than that of the nucleus but not of the oocyte, implicating a non-nuclear but sub-cellular target. This is consistent with results from 3H-thymidine incorporated in DNA. Our efforts to identify the extraordinarily radiosensitive lethality target in these primordial oocytes suggest it is the plasma membrane. Monte Carlo calculations for 0.43-MeV neutrons show that at the D37 only a single proton recoil will traverse the plasma membrane, consistent with the observed exponential survival curve. A highly sensitive non-DNA target for mouse oocyte killing may importantly influence interpretations of genetic mutation data from mice and their use in estimating genetic risk in humans. 7 refs., 1 fig., 1 tab

  10. Susceptibility of various mosquitoes of California to subperiodic Brugia malayi.

    Science.gov (United States)

    Bangs, M J; Ash, L R; Barr, A R

    1995-08-01

    Laboratory experiments were conducted to determine the susceptibility of six species of mosquitoes, representing three genera, to subperiodic Brugia malayi. The black-eye, Liverpool strain of Aedes aegypti was the susceptible control. Mosquitoes were fed on microfilaremic jirds (Meriones unguiculatus). All mosquitoes, except wild caught Culex erythrothorax, were laboratory-reared and allowed to feed when 8 to 10 days old. Anopheles freeborni, Anopheles hermsi, and Culiseta inornata proved refractory. Both Anopheles species allowed invasion of flight muscle and development to the late first stage, after which larval growth ceased and melanization occurred. Culiseta inornata prevented any larval development. Culex tarsalis and Cx. erythrothorax proved highly susceptible to B. malayi infection. In all, 95.6% and 88.7% of the Cx. tarsalis harbored third-stage larvae after infective feedings of 15.7 and 81.8 mf/microliters of blood, respectively, while only 11.5% were found susceptible when microfilaremia was low (1.1 mf/microliters). Culex erythrothorax demonstrated a susceptibility rate of 82.3% with 17.0 mf/microliters. Both Culex species appear to be excellent experimental hosts for subperiodic B. malayi. This is the first conclusive evidence that mosquitoes of the genus Culex can naturally support the complete development of a stain of subperiodic B. malayi. PMID:8533667

  11. Yellow Fever Virus Infectivity for Bolivian Aedes aegypti Mosquitoes

    OpenAIRE

    Mutebi, John-paul; Gianella, Alberto; Travassos Da Rosa, Amelia; Tesh, Robert B.; Barrett, Alan D. T.; Higgs, Stephen

    2004-01-01

    The absence of urban yellow fever virus (YFV) in Bolivian cities has been attributed to the lack of competent urban mosquito vectors. Experiments with Aedes aegypti from Santa Cruz, Bolivia, demonstrated infection (100%), dissemination (20%), and transmission of a Bolivian YFV strain (CENETROP-322).

  12. Modelling parasitism and predation of mosquitoes by water mites.

    Science.gov (United States)

    Esteva, Lourdes; Rivas, Gerardo; Yang, Hyun Mo

    2006-10-01

    Parasitism and predation are two ecological interactions that can occur simultaneously between two species. This is the case of Culicidae (Insecta: Diptera) and water mites (Acari: Hydrachnidia). The larva mites are~parasites of aquatic and semiaquatic insects, and deutonymphs and adults are predators of insect larvae and eggs. Since several families of water mites are associated with mosquitoes there is an interest in the potential use of these mites as biological control agents. The aim of this paper is to use mathematical modelling and analysis to assess the impact of predation and parasitism in the mosquito population. We propose a system of ordinary differential equations to model the interactions among the larval and adult stages of mosquitoes and water mites. The model exhibits three equilibria: the first equilibrium point corresponds to the state where the two species are absent, the second one to the state where only mosquitoes are present (water mites need insects to complete their life cycle), and the third one is the coexistence equilibrium. We analyze conditions for the asymptotic stability of equilibria, supported by analytical and numerical methods. We discuss the different scenarios that appear when we change the parasitism and predation parameters. High rates of parasitism and moderate predation can drive two species to a stable coexistence. PMID:16897016

  13. DEVICE FOR FISH ADDITIONAL FEEDING ON MOSQUITO LARVAE ?????????? ??? ????????? ???? ????????? ???????

    Directory of Open Access Journals (Sweden)

    Gazalov V. S.

    2013-03-01

    Full Text Available The electro optical transducer with changeable emission color depending on air temperature, which is destined for fish additional feeding with mosquito larvae, has been designed. It is the effective device of electrotechnics of ecological fish additional feeding with live feed

  14. Formulas of components of citronella oil against mosquitoes (Aedes aegypti).

    Science.gov (United States)

    Hsu, Wey-Shin; Yen, Jui-Hung; Wang, Yei-Shung

    2013-01-01

    The mosquito Aedes aegypti is an epidemic vector of several diseases such as dengue fever and yellow fever. Several pesticides are used to control the mosquito population. Because of their frequent use, some mosquitoes have developed resistance. In this study, we used the Y-tube olfactometer to test essential oils of Cymbopogon species and screened specific formulas of components as repellents against Ae. aegypti. At 400 ?L, the extracted oil of citronella grass (Cymbopogon nardus) and myrcene produced a low-active response by inhibiting mosquito host-seeking activity. Citronella grass, lemon grass (Cymbopogon citratus), citral and myrcene also produced a low-treatment response to repellents, for more potential to affect host-seeking behavior. Furthermore, the mixture of citral, myrcene, and citronellal oil (C:M:Ci = 6:4:1) greatly affected and inhibited host-seeking behavior (76% active response; 26% treatment response with 40 ?L; 42.5%, 18% with 400 ?L; and 19%, 23% with 1000 ?L). As compared with the result for N,N-diethyl-3-methylbenzamide (DEET; 44%, 22% with 400 ?L), adjusting the composition formulas of citronella oil had a synergistic effect, for more effective repellent against Ae. aegypti. PMID:23998314

  15. Evaluation of a Stable Isotope Method to Mark Naturally-Breeding Larval Mosquitoes for Adult Dispersal Studies

    OpenAIRE

    Hamer, Gabriel L.; Donovan, Danielle J.; Hood-Nowotny, Rebecca; KAUFMAN, MICHAEL G.; GOLDBERG, TONY L.; WALKER, EDWARD D.

    2012-01-01

    Understanding mosquito dispersal is critically important for vector-borne disease control and prevention. Mark–release–recapture methods using various marking techniques have made substantial contributions to the study of mosquito biology. However, the ability to mark naturally breeding mosquitoes noninvasively and with life-long retention has remained problematic. Here, we describe a method to mark naturally breeding mosquitoes with stable isotopes. Culexpipiens f. molestus mosquitoes we...

  16. 40 CFR 180.1107 - Delta endotoxin of Bacillus thuringiensis variety kurstaki encapsulated into killed Pseudomonas...

    Science.gov (United States)

    2010-07-01

    ...variety kurstaki encapsulated into killed Pseudomonas fluorescens; exemption from the requirement...kurstaki encapsulated into killed Pseudomonas fluorescens; exemption from the requirement...kurstaki encapsulated into killed Pseudomonas fluorescens is exempt from the...

  17. 77 FR 1023 - Regulated Navigation Area; Arthur Kill, NY and NJ

    Science.gov (United States)

    2012-01-09

    ...Gulfport Reach in the Arthur Kill. Consult the first TIR for...operations began in the Arthur Kill on Tuesday, August 2, 2011...Order 12988), protection of children (Executive Order 13045...Regulated Navigation Area; Arthur Kill, NY and NJ. * * * * *...

  18. Evaluación de la trampa Mosquito Magnet® con y sin octenol para capturar mosquitos (Diptera: Culicidae) / Evaluation of the Mosquito Magnet® trap with and without octenol to collect mosquitoes (Diptera: Culicidae)

    Scientific Electronic Library Online (English)

    Yasmin, Rubio-Palis; Rodrigo, Ramírez Álvarez; Hernán, Guzmán; Yarys, Estrada.

    2014-06-01

    Full Text Available La eficiencia de la trampa Mosquito Magnet® Liberty Plus (MMLP) fue evaluada con y sin octenol para capturar mosquitos hembras adultas en Maracay, estado Aragua, Venezuela. Se realizaron capturas dos veces por semana entre las 3:00 pm y 10:00 am, un día con y otro sin octenol, durante ocho semanas e [...] ntre abril y mayo 2013 para un total de 152 horas de capturas para cada tratamiento. Se capturaron un total de 229 especímenes pertenecientes a 10 especies distribuidas en cinco géneros. En general, se capturó un número similar de mosquitos con y sin octenol. No se observaron diferencias significativas entre ambos tratamientos para las especies más abundantes (Anopheles pseudopunctipennis y Aedes angustivittatus) así como para el total de mosquitos capturados. Para ambos tratamientos se capturaron proporciones similares de hembras de Aedes aegypti y Ae. albopictus. Sin embargo, se capturaron significativamente más Culex quinquefasciatus sin octenol que con octenol. Los resultados sugieren que es factible prescindir del uso de octenol en trampas MMLP en futuros estudios de vigilancia entomológica para la prevención y control de la malaria, dengue y otros arbovirus, particularmente en áreas remotas. Sin embargo, es fundamental realizar más evaluaciones en áreas endémicas en épocas de alta abundancia de mosquitos a fin de obtener una mejor estimación de la eficacia de la trampa con y sin octenol. Abstract in english The efficiency of the Mosquito Magnet® Liberty Plus (MMLP) trap was evaluated with and without octenol for the capture of adult female mosquitoes in Maracay, Aragua state, Venezuela. Captures were carried out twice a week between 3:00 pm and 10:00 am, one day with octenol and the following without i [...] t, during 8 weeks between April and May, 2013 with a total of 152 hours of sampling effort per treatment. A total of 229 specimens belonging to 10 species distributed in 5 genera were caught. In general, similar numbers of mosquitoes were caught in traps both with and without octenol. No significant differences were observed between the two treatments for the two most abundant species (Anopheles pseudopunctipennis and Aedes angustivittatus) or for the total number of mosquitoes captured. Similar proportions of Aedes aegypti and Ae. albopictus females were also captured independent of the treatment used. However, significantly more Culex quinquefasciatus were caught in the traps without octenol. The results suggest that it is feasible to use the MMLP traps without octenol in future studies of entomological surveillance for the prevention and control of malaria, dengue and other arboviruses, especially in remote areas. Nevertheless, further evaluations in endemic areas should be done during periods of higher mosquito abundance in order to obtain a more precise estimate of the effectiveness of traps with and without octenol.

  19. [The pathogens of Taiwan mosquitoes--Coelomomyces species].

    Science.gov (United States)

    Lien, J C; Lin, Y N

    1990-07-01

    A brief mention was made of the history of world studies on the Coelomomyces fungi, the life cycle of the fungi, their importance as biological agents for mosquito control, and the known ecological information concerning the Taiwan mosquitoes parasitized by the fungi. Special accounts were made of the results of experiments infecting four mosquito species, Aedes aegypti, Ae. albopictus, Ae. triseriatus and Tripteroides aranoides with Coelomomyces stegomyiae var. chapmani, using the copepod, Phyllognathopus viguieri as an alternate host. The dead 4th instar larvae of Ae. albopictus containing sporangia were put together with healthy copepods for 10 days, then healthy 2nd instar mosquito larvae were added for a 1-day exposure. Then the larvae were transferred to clean water and subsequent examinations for signs of infection were made at 3-day intervals for a period of 21 days. The experiments demonstrated an infection rate of 59.7% and 90% respectively for Ae. albopictus and Ae. aegypti in the first trial, 18.5% and 23.3% in the 2nd trial, and none in the 3rd trial. The low infection rate in the 2nd trial and no infection in the 3rd trial were thought to be due to the extensive contamination of test water with algae. Therefore, in the 4th trial the rearing water was renewed with dechlorinated tap water and new copepods instroduced. The infection rate again rose to 41.1% and 56% respectively for the two species. Experiments with Ae. triseriatus and Tp. aranoides failed to produce signs of infection. Experimental infection of susceptible Ae. albopictus larvae with the sporangia stored at 8 degrees C showed that storage for one month produced an infection rate of 38.2%. However, storage for two months or longer produced no infection in the larvae of the same mosquito species. PMID:1976138

  20. Biodistribution and Trafficking of Hydrogel Nanoparticles in Adult Mosquitoes

    Science.gov (United States)

    Paquette, Cynthia C. H.; Phanse, Yashdeep; Perry, Jillian L.; Sanchez-Vargas, Irma; Airs, Paul M.; Dunphy, Brendan M.; Xu, Jing; Carlson, Jonathan O.; Luft, J. Christopher; DeSimone, Joseph M.; Bartholomay, Lyric C.; Beaty, Barry J.

    2015-01-01

    Background Nanotechnology offers great potential for molecular genetic investigations and potential control of medically important arthropods. Major advances have been made in mammalian systems to define nanoparticle (NP) characteristics that condition trafficking and biodistribution of NPs in the host. Such information is critical for effective delivery of therapeutics and molecules to cells and organs, but little is known about biodistribution of NPs in mosquitoes. Methodology/Principal Findings PRINT technology was used to construct a library of fluorescently labeled hydrogel NPs of defined size, shape, and surface charge. The biodistribution (organ, tissue, and cell tropisms and trafficking kinetics) of positively and negatively charged 200 nm x 200 nm, 80 nm x 320 nm, and 80 nm x 5000 nm NPs was determined in adult Anopheles gambiae mosquitoes as a function of the route of challenge (ingestion, injection or contact) using whole body imaging and fluorescence microscopy. Mosquitoes readily ingested NPs in sugar solution. Whole body fluorescence imaging revealed substantial NP accumulation (load) in the alimentary tracts of the adult mosquitoes, with the greatest loads in the diverticula, cardia and foregut. Positively and negatively charged NPs differed in their biodistribution and trafficking. Following oral challenge, negatively charged NPs transited the alimentary tract more rapidly than positively charged NPs. Following contact challenge, negatively charged NPs trafficked more efficiently in alimentary tract tissues. Following parenteral challenge, positively and negatively charged NPs differed in tissue tropisms and trafficking in the hemocoel. Injected NPs were also detected in cardia/foregut, suggesting trafficking of NPs from the hemocoel into the alimentary tract. Conclusions/Significance Herein we have developed a tool box of NPs with the biodistribution and tissue tropism characteristics for gene structure/function studies and for delivery of vector lethal cargoes for mosquito control. PMID:25996505

  1. Genetic methods for control of mosquitoes and biting flies

    International Nuclear Information System (INIS)

    The earliest research efforts on using genetic methods for the control of mosquitoes and biting flies concentrated on the evaluation of the sterile insect technique (SIT). Several successful, but generally small scale, research efforts with mosquitoes clearly documented that either chemosterilized or radiation sterilized males were effective in causing a level of genetic load that would be sufficient for the reduction or eradication of natural populations of several species. Genetic sexing strains of several species of mosquitoes have been assembled, and this aspect of breeding specialty strains is not a limiting factor in the implementation of SIT. In the largest field experiment, conducted with Anopheles albimanus in El Salvador during the 1970s, a genetic sexing strain was used operationally in a factory that produced one million sterile males per day over a one year period. Technical problems that would require extensive research of a practical nature before the implementation of SIT for mosquito control involve primarily better means for the rearing, sterilization and distribution of the insects. A successful experiment was conducted to eliminate the stable fly on the island of St. Croix, the United States Virgin Islands, and since this work in the 1970s, genetic sexing strains have been developed. A considerable amount of effort was expended on the synthesis of chromosome aberrations for the control of mosquitoes. Although the results of experimental trials indigh the results of experimental trials indicated that aberration bearing insects could effectively inject a genetic load into the natural population, no large scale tests have ever been conducted to evaluate fully the real effectiveness of induced chromosomal aberrations. More recently, most of the research work in genetic control has been aimed at the use of recombinant DNA techniques for the development of new technology. All of these topics and an assessment of their value are discussed. (author). 30 refs

  2. Maternally transmitted target antigen for unrestricted killing by NZB T lymphocytes

    OpenAIRE

    1980-01-01

    A new target antigen for unrestricted killing was defined by NZB T lymphocytes which were immunized and restimulated with H-2-identical BALB/c spleen cells. These effector cells killed nearly all target cells tested, irrespective of their H-2 type, but did not kill NZB target cells. The response was shown to have three major components: unrestricted killing specific for Qed-1b, H-2d-restricted killing specific for minor histocompatibility antigens, and unrestricted killing specific for a new ...

  3. HIV transcription is induced with some forms of cell killing

    International Nuclear Information System (INIS)

    Using HeLa cells stably transfected with an HIV-LTR-CAT construct', we demonstrated a peak in CAT induction that occurs in viable (but not necessarily cell-division-competent) cells 24 h following exposure to some cell-killing agents. ? rays were the only cell-killing agent which did not induce HIV transcription; this can be attributed to the fact that ?-ray-induced apoptotic death requires function p53, which is missing in HeLa cells. For all other agents, HIV-LTR induction was dose-dependent and correlated with the amount of cell killing that occurred in the culture

  4. Fish Kills in Ireland in 1994 and 1995

    OpenAIRE

    Moriarty, C.

    1996-01-01

    In 1994, the downward trend in numbers of fish kills continued, the total for the year being 32. However, in 1995 a long spell of dry weather greatly reduced the flow in rivers in all parts of Ireland and the number of fish kills rose to 84, the highest since 1989. In 1994, farmyard effluents, silage and slurry together accounted for one third of the fish kills. Industrial effluents and enrichment both caused 19% of the total. Storm water runoff and cement spillage in building operations w...

  5. Special Killing forms on toric Sasaki–Einstein manifolds

    International Nuclear Information System (INIS)

    In this paper we study the interplay between complex coordinates on the Calabi–Yau metric cone and the special Killing forms on the toric Sasaki–Einstein manifold. First, we give a procedure to locally construct the special Killing forms. Finally, we exemplify the general scheme in the case of the five-dimensional Yp,q spaces, identifying the additional special Killing 2-forms which were previously obtained using a different method by Visinescu (2012 Mod. Phys. Lett. A 27 1250217). (paper)

  6. Factors Affecting Zebra Mussel Kill by the Bacterium Pseudomonas fluorescens

    Energy Technology Data Exchange (ETDEWEB)

    Daniel P. Molloy

    2004-02-24

    The specific purpose of this research project was to identify factors that affect zebra mussel kill by the bacterium Pseudomonas fluorescens. Test results obtained during this three-year project identified the following key variables as affecting mussel kill: treatment concentration, treatment duration, mussel siphoning activity, dissolved oxygen concentration, water temperature, and naturally suspended particle load. Using this latter information, the project culminated in a series of pipe tests which achieved high mussel kill inside power plants under once-through conditions using service water in artificial pipes.

  7. Potential impacts of climate change on the ecology of dengue and its mosquito vector the Asian tiger mosquito (Aedes albopictus)

    Science.gov (United States)

    Erickson, R. A.; Hayhoe, K.; Presley, S. M.; Allen, L. J. S.; Long, K. R.; Cox, S. B.

    2012-09-01

    Shifts in temperature and precipitation patterns caused by global climate change may have profound impacts on the ecology of certain infectious diseases. We examine the potential impacts of climate change on the transmission and maintenance dynamics of dengue, a resurging mosquito-vectored infectious disease. In particular, we project changes in dengue season length for three cities: Atlanta, GA; Chicago, IL and Lubbock, TX. These cities are located on the edges of the range of the Asian tiger mosquito within the United States of America and were chosen as test cases. We use a disease model that explicitly incorporates mosquito population dynamics and high-resolution climate projections. Based on projected changes under the Special Report on Emissions Scenarios (SRES) A1fi (higher) and B1 (lower) emission scenarios as simulated by four global climate models, we found that the projected warming shortened mosquito lifespan, which in turn decreased the potential dengue season. These results illustrate the difficulty in predicting how climate change may alter complex systems.

  8. The effect of Mosquito Magnet Liberty Plus trap on the human mosquito biting rate under semi-field conditions.

    Science.gov (United States)

    Kitau, Jovin; Pates, Helen; Rwegoshora, Theophil R; Rwegoshora, Dionis; Matowo, Johnson; Kweka, Eliningaya J; Mosha, Franklin W; McKenzie, Karen; Magesa, Stephen M

    2010-09-01

    This study evaluated the efficacy of a commercially available mosquito trap, the Mosquito Magnet Liberty Plus (MM), in reducing human biting rates under semi-field conditions when used alone or with different types of repellents. The MM trap significantly reduced the human biting rate with both laboratory-reared Culex quinquefasciatus and Anopheles gambiae sensu stricto. The MM trap catch did not increase when a mosquito coil was burned but did significantly increase when a skin repellent was applied to the human bait. Microencapsulated repellent ankle bands did not increase the MM trap catch with either Cx. quinquefasciatus or An. gambiae s.s., although its combination with the trap was more effective at reducing bites by Cx. quinquefasciatus. The absence of the commercial attractant Lurex3 in traps significantly lowered the catch efficiency of Cx. quinquefasciatus even when the skin repellent was applied to volunteers. The results from this study showed that the use of a skin repellent and an attractant-baited trap can significantly reduce the human biting rate of both nuisance biting mosquitoes and malaria vectors. Further work is required to investigate how this push-pull system would work in a field environment. PMID:21033055

  9. Potential impacts of climate change on the ecology of dengue and its mosquito vector the Asian tiger mosquito (Aedes albopictus)

    International Nuclear Information System (INIS)

    Shifts in temperature and precipitation patterns caused by global climate change may have profound impacts on the ecology of certain infectious diseases. We examine the potential impacts of climate change on the transmission and maintenance dynamics of dengue, a resurging mosquito-vectored infectious disease. In particular, we project changes in dengue season length for three cities: Atlanta, GA; Chicago, IL and Lubbock, TX. These cities are located on the edges of the range of the Asian tiger mosquito within the United States of America and were chosen as test cases. We use a disease model that explicitly incorporates mosquito population dynamics and high-resolution climate projections. Based on projected changes under the Special Report on Emissions Scenarios (SRES) A1fi (higher) and B1 (lower) emission scenarios as simulated by four global climate models, we found that the projected warming shortened mosquito lifespan, which in turn decreased the potential dengue season. These results illustrate the difficulty in predicting how climate change may alter complex systems. (letter)

  10. Did Vertigo Kill America's Forgotten Astronaut?

    Science.gov (United States)

    Bendrick, Gregg A.; Merlin, Peter W.

    2007-01-01

    On November 15, 1967, U.S. Air Force test pilot Major Michael J. Adams was killed while flying the X-15 rocket-propelled research vehicle in a parabolic spaceflight profile. This flight was part of a joint effort with NASA. An electrical short in one of the experiments aboard the vehicle caused electrical transients, resulting in excessive workload by the pilot. At altitude Major Adams inappropriately initiated a flat spin that led to a series of unusual aircraft attitudes upon atmospheric re-entry, ultimately causing structural failure of the airframe. Major Adams was known to experience vertigo (i.e. spatial disorientation) while flying the X-15, but all X-15 pilots most likely experienced vertigo (i.e. somatogravic, or "Pitch-Up", illusion) as a normal physiologic response to the accelerative forces involved. Major Adams probably experienced vertigo to a greater degree than did others, since prior aeromedical testing for astronaut selection at Brooks AFB revealed that he had an unusually high degree of labyrinthine sensitivity. Subsequent analysis reveals that after engine burnout, and through the zenith of the flight profile, he likely experienced the oculoagravic ("Elevator") illusion. Nonetheless, painstaking investigation after the mishap revealed that spatial disorientation (Type II, Recognized) was NOT the cause, but rather, a contributing factor. The cause was in fact the misinterpretation of a dual-use flight instrument (i.e. Loss of Mode Awareness), resulting in confusion between yaw and roll indications, with subsequent flight control input that was inappropriate. Because of the altitude achieved on this flight, Major Adams was awarded Astronaut wings posthumously. Understanding the potential for spatial disorientation, particularly the oculoagravic illusion, associated with parabolic spaceflight profiles, and understanding the importance of maintaining mode awareness in the context of automated cockpit design, are two lessons that have direct application to the commercial space industry today.

  11. Fighting Arbovirus Transmission: Natural and Engineered Control of Vector Competence in Aedes Mosquitoes

    Directory of Open Access Journals (Sweden)

    Joy Kean

    2015-03-01

    Full Text Available Control of aedine mosquito vectors, either by mosquito population reduction or replacement with refractory mosquitoes, may play an essential role in the fight against arboviral diseases. In this review, we will focus on the development and application of biological approaches, both natural or engineered, to limit mosquito vector competence for arboviruses. The study of mosquito antiviral immunity has led to the identification of a number of host response mechanisms and proteins that are required to control arbovirus replication in mosquitoes, though more factors influencing vector competence are likely to be discovered. We will discuss key aspects of these pathways as targets either for selection of naturally resistant mosquito populations or for mosquito genetic manipulation. Moreover, we will consider the use of endosymbiotic bacteria such as Wolbachia, which in some cases have proven to be remarkably efficient in disrupting arbovirus transmission by mosquitoes, but also the use of naturally occurring insect-specific viruses that may interfere with arboviruses in mosquito vectors. Finally, we will discuss the use of paratransgenesis as well as entomopathogenic fungi, which are also proposed strategies to control vector competence.

  12. (M-theory-)Killing spinors on symmetric spaces

    CERN Document Server

    Hustler, Noel

    2015-01-01

    We show how the theory of invariant principal bundle connections for reductive homogeneous spaces can be applied to determine the holonomy of generalised Killing spinor covariant derivatives of the form $D= \

  13. Hidden symmetries and Killing tensors on curved spaces

    CERN Document Server

    Ianus, Stere; Vilcu, Gabriel-Eduard

    2008-01-01

    Higher order symmetries corresponding to Killing tensors are investigated. The intimate relation between Killing-Yano tensors and non-standard supersymmetries is pointed out. In the Dirac theory on curved spaces, Killing-Yano tensors generate Dirac type operators involved in interesting algebraic structures as dynamical algebras or even infinite dimensional algebras or superalgebras. The general results are applied to space-times which appear in modern studies. One presents the infinite dimensional superalgebra of Dirac type operators on the 4-dimensional Euclidean Taub-NUT space that can be seen as a twisted loop algebra. The existence of the conformal Killing-Yano tensors is investigated for some spaces with mixed Sasakian structures.

  14. Breath-Holding Games Are Killing Swimmers, CDC Warns

    Science.gov (United States)

    Breath-Holding Games Are Killing Swimmers, CDC Warns Even seasoned athletes are drowning because of dangerous underwater behaviors, agency says To ... warning about accidental drownings from underwater breath-holding games and exercises. Whether as horseplay or part of ...

  15. Fish Kill Investigations : St. Vincent National Wildlife Refuge

    US Fish and Wildlife Service, Department of the Interior — This memo summarizes an investigation that took place after a massive fish kill in 5 of the 6 ponds on St. Vincent National Wildlife Refuge. Two days of field...

  16. On Killing vectors and harmonic vectors at quantization of gravitation

    International Nuclear Information System (INIS)

    Attention is paid to two shortcomings occuring at quantization in the curved spacetime: mathematical shortcoming consisting in the killing vector absence in arbitrary Riemann space and physical one consisting in absence of energy-momentum tensor of the gravitational field. It is shown, that both shortcomings may be removed, if the killing vectors are replaced by harmonic vectors corresponding to shift generators of the Poincare group existing in arbitrary Riemann space

  17. Human polymorphonuclear neutrophils specifically recognize and kill cancerous cells

    OpenAIRE

    Yan, Jun; Kloecker, Goetz; Fleming, Chris; Bousamra, Michael; Hansen, Richard; Hu, Xiaoling; Ding, Chuanlin; Cai, Yihua; Xiang, Dong; Donninger, Howard; Eaton, John W.; Clark, Geoffrey J

    2014-01-01

    Polymorphonuclear neutrophils (PMNs), the main effectors of the innate immune system, have rarely been considered as an anticancer therapeutic tool. However, recent investigations using animal models and preliminary clinical studies have highlighted the potential antitumor efficacy of PMNs. In the current study, we find that PMNs from some healthy donors naturally have potent cancer-killing activity against 4 different human cancer cell lines. The killing activity appears to be cancer cell-sp...

  18. Conformal Killing vector fields and a virial theorem

    CERN Document Server

    Cariñena, José F; Martínez, Eduardo; Santos, Patrícia

    2014-01-01

    The virial theorem is formulated both intrinsically and in local coordinates for a Lagrangian system of mechanical type on a Riemann manifold. An import case studied in this paper is that of an affine virial function associated to a vector field on the configuration manifold. The special cases of a virial function associated to a Killing, a homothetic and a conformal Killing vector field are considered and the corresponding virial theorems are established for this type of functions.

  19. Conformal Killing vector fields and a virial theorem

    Science.gov (United States)

    Cariñena, José F.; Gheorghiu, Irina; Martínez, Eduardo; Santos, Patrícia

    2014-11-01

    The virial theorem is formulated both intrinsically and in local coordinates for a Lagrangian system of a mechanical type on a Riemann manifold. An important case studied in this paper is that of an affine virial function associated with a vector field on the configuration manifold. The special cases of a virial function associated with a Killing, a homothetic, and a conformal Killing vector field are considered and the corresponding virial theorems are established for these types of functions.

  20. Conformal Killing vector fields and a virial theorem

    International Nuclear Information System (INIS)

    The virial theorem is formulated both intrinsically and in local coordinates for a Lagrangian system of a mechanical type on a Riemann manifold. An important case studied in this paper is that of an affine virial function associated with a vector field on the configuration manifold. The special cases of a virial function associated with a Killing, a homothetic, and a conformal Killing vector field are considered and the corresponding virial theorems are established for these types of functions. (paper)

  1. Conformal Killing vector fields and a virial theorem

    OpenAIRE

    Cariñena, José F.; Gheorghiu, Irina; Martínez, Eduardo; Santos, Patrícia

    2014-01-01

    The virial theorem is formulated both intrinsically and in local coordinates for a Lagrangian system of mechanical type on a Riemann manifold. An import case studied in this paper is that of an affine virial function associated to a vector field on the configuration manifold. The special cases of a virial function associated to a Killing, a homothetic and a conformal Killing vector field are considered and the corresponding virial theorems are established for this type of fu...

  2. Pseudomonas aeruginosa PAO1 Kills Caenorhabditis elegans by Cyanide Poisoning

    OpenAIRE

    Gallagher, Larry A; Manoil, Colin

    2001-01-01

    In this report we describe experiments to investigate a simple virulence model in which Pseudomonas aeruginosa PAO1 rapidly paralyzes and kills the nematode Caenorhabditis elegans. Our results imply that hydrogen cyanide is the sole or primary toxic factor produced by P. aeruginosa that is responsible for killing of the nematode. Four lines of evidence support this conclusion. First, a transposon insertion mutation in a gene encoding a subunit of hydrogen cyanide synthase (hcnC) eliminated ne...

  3. Illegal killing for ivory drives global decline in African elephants

    OpenAIRE

    Wittemyer, George; Northrup, Joseph M.; Blanc, Julian; Douglas-hamilton, Iain; Omondi, Patrick; Burnham, Kenneth P.

    2014-01-01

    Illegal harvest for commercial trade has recently surged to become a major threat to some of the world’s most endangered and charismatic species. Unfortunately, the cryptic nature of illegal killing makes estimation of rates and impacts difficult. Applying a model based on field census of carcasses, to our knowledge we provide the first detailed assessment of African elephant illegal killing rates at population, regional, and continental scales. Illegal harvest for commercial trade in ivory...

  4. Special Killing forms on toric Sasaki-Einstein manifolds

    CERN Document Server

    Slesar, Vladimir; Vilcu, Gabriel Eduard

    2014-01-01

    In this paper we study the interplay between complex coordinates of the Calabi-Yau metric cone and the special Killing forms on the toric Sasaki-Einstein manifold. In the general case we give a procedure to locally construct the special Killing forms. In the final part we exemplify the general scheme in the case of the 5-dimensional $Y^{p,q}$ spaces.

  5. Registros de mayor altitud para mosquitos (Diptera: Culicidae) en Venezuela

    Scientific Electronic Library Online (English)

    Juan-Carlos, Navarro; Fabiola, Del Ventura; Adriana, Zorrilla; Jonathan, Liria.

    2010-03-01

    Full Text Available Los mosquitos (Diptera: Culicidae) son insectos holometábolos con estadios inmaduros acuáticos que utilizan una amplia variedad de hábitats larvales, desde cuerpos de agua en el suelo hasta Fitotelmata (depósitos de agua en las plantas) y depósitos artificiales. La disponibilidad de sitios de reprod [...] ucción a menudo determina el límite superior del ámbito de los mosquitos. Nosotros construimos una base de datos de 9 607 registros, 432 localidades, 19 géneros y 254 especies. La coordillera Andina posee el 77% de los registros con mayor altitud incluyendo Aedes euris con un registro a 3 300 m, seguido por tres especies de Anopheles -subgénero Kerteszia- con una altitud máxima de 2 680 m. Wyeomyia bicornis y Culex daumastocampa a 2 550 m fueron los registros de mayor altitud en la cordillera Costera- Central, mientras que el record más alto en Pantepui fue Wyeomyia zinzala a 2 252 m. El 60% de los registros de máxima altitud están representados por especies asociadas con fitotelmata (Bromeliaceae y Sarraceniaceae). Los límites superiores de Culex quinquefasciatus y Anopheles (Kerteszia) podría representar el límite teórico para la transmisión de filariasis o arbovirus, por Culex y malaria por Anopheles (Kerteszia) en Venezuela. Del mismo modo, un vector del dengue, Aedes aegypti, no ha sido registrado por encima de 2 000 m. Abstract in english Highest mosquito records (Diptera: Culicidae) in Venezuela. Mosquitoes (Diptera: Culicidae) are holometabolous insects with aquatic immature stages, which use a broad variety of larval habitats, from ground water bodies to Phytothelmata (water deposits in plants) and artificial deposits. The availab [...] ility of breeding sites often determines the upper limits of mosquito ranges. We built a database with 9 607 records with 432 localities, 19 genera and 254 species. The Andean mountains have 77% of the highest mosquito records including Aedes euris with record at 3 133 m, followed by three species of Anopheles -subgenera Kerteszia- with the upper limit of 2 680 m. Wyeomyia bicornis and Culex daumastocampa at 2 550 m were the highest records in the Central- Coastal cordillera, while the highest record in Pantepui was Wyeomyia zinzala at 2 252 m. The species associated with phytothelmata (Bromeliaceae and Sarraceniaceae) represent 60% of the records. The upper limits of Culex quinquefasciatus and Anopheles (Kerteszia) species could represent the theoretical limit for transmission of filariasis or arboviruses, by Culex, and malaria by Anopheles (Kerteszia) in Venezuela. Similarly, a vector of Dengue, Aedes aegypti, has not been not recorded above 2 000 m. Rev. Biol. Trop. 58 (1): 245-254. Epub 2010 March 01.

  6. Registros de mayor altitud para mosquitos (Diptera: Culicidae en Venezuela

    Directory of Open Access Journals (Sweden)

    Juan-Carlos Navarro

    2010-03-01

    Full Text Available Los mosquitos (Diptera: Culicidae son insectos holometábolos con estadios inmaduros acuáticos que utilizan una amplia variedad de hábitats larvales, desde cuerpos de agua en el suelo hasta Fitotelmata (depósitos de agua en las plantas y depósitos artificiales. La disponibilidad de sitios de reproducción a menudo determina el límite superior del ámbito de los mosquitos. Nosotros construimos una base de datos de 9 607 registros, 432 localidades, 19 géneros y 254 especies. La coordillera Andina posee el 77% de los registros con mayor altitud incluyendo Aedes euris con un registro a 3 300 m, seguido por tres especies de Anopheles -subgénero Kerteszia- con una altitud máxima de 2 680 m. Wyeomyia bicornis y Culex daumastocampa a 2 550 m fueron los registros de mayor altitud en la cordillera Costera- Central, mientras que el record más alto en Pantepui fue Wyeomyia zinzala a 2 252 m. El 60% de los registros de máxima altitud están representados por especies asociadas con fitotelmata (Bromeliaceae y Sarraceniaceae. Los límites superiores de Culex quinquefasciatus y Anopheles (Kerteszia podría representar el límite teórico para la transmisión de filariasis o arbovirus, por Culex y malaria por Anopheles (Kerteszia en Venezuela. Del mismo modo, un vector del dengue, Aedes aegypti, no ha sido registrado por encima de 2 000 m.Highest mosquito records (Diptera: Culicidae in Venezuela. Mosquitoes (Diptera: Culicidae are holometabolous insects with aquatic immature stages, which use a broad variety of larval habitats, from ground water bodies to Phytothelmata (water deposits in plants and artificial deposits. The availability of breeding sites often determines the upper limits of mosquito ranges. We built a database with 9 607 records with 432 localities, 19 genera and 254 species. The Andean mountains have 77% of the highest mosquito records including Aedes euris with record at 3 133 m, followed by three species of Anopheles -subgenera Kerteszia- with the upper limit of 2 680 m. Wyeomyia bicornis and Culex daumastocampa at 2 550 m were the highest records in the Central- Coastal cordillera, while the highest record in Pantepui was Wyeomyia zinzala at 2 252 m. The species associated with phytothelmata (Bromeliaceae and Sarraceniaceae represent 60% of the records. The upper limits of Culex quinquefasciatus and Anopheles (Kerteszia species could represent the theoretical limit for transmission of filariasis or arboviruses, by Culex, and malaria by Anopheles (Kerteszia in Venezuela. Similarly, a vector of Dengue, Aedes aegypti, has not been not recorded above 2 000 m. Rev. Biol. Trop. 58 (1: 245-254. Epub 2010 March 01.

  7. The cell biology of malaria infection of mosquito: advances and opportunities

    Science.gov (United States)

    Sinden, R E

    2015-01-01

    Recent reviews (Feachem et?al.; Alonso et?al.) have concluded that in order to have a sustainable impact on the global burden of malaria, it is essential that we knowingly reduce the global incidence of infected persons. To achieve this we must reduce the basic reproductive rate of the parasites to mosquitoes relative to the number of persons, the mosquito/human biting rate, the proportion of mosquitoes carrying infectious sporozoites, the daily survival rate of the infectious mosquito and the ability of malaria-infected persons to infect mosquito vectors. This paper focuses on our understanding of parasite biology underpinning the last of these terms: infection of the mosquito. The article attempts to highlight central issues that require further study to assist in the discovery of useful transmission-blocking measures. PMID:25557077

  8. [Omics of vector mosquitoes: a big data platform for vector biology and vector-borne diseases].

    Science.gov (United States)

    Wu, Yang; Xie, Li-Hua; Liu, Pei-Wen; Li, Xiao-Cong; Yan, Gui-Yun; Chen, Xiao-Guang

    2015-05-20

    Recently the studies on mosquito genomics, transcriptomics and small RNAomics developed rapidly with the novel biotechnologies of the next generation sequencing techniques. The genome sequences of several important vector mosquitoes including Anopheles gambiae, Culex quinquefasciatus, and Aedes aegypti have been published. The genome sizes vary among the different species of mosquitoes and are consistent with the number of the repeat regions. The released genome sequences facilitate gene cloning and identification as for OBP, OR and dsx genes. Transcriptomics provides a useful tool for functional analyses of the mosquito genes, and using this technique, the molecular basis of mosquito blooding, gland proteins and diapauses have been explored. Studies on small RNAomics suggest important roles of miRNAs and piRNAs in ovary development, blood digestion, and immunity against virus infection. The studies on mosquito omics have generated a big data platform for investigation of vector biology and vector-transmitted disease prevention. PMID:26018253

  9. The cell biology of malaria infection of mosquito: advances and opportunities.

    Science.gov (United States)

    Sinden, R E

    2015-04-01

    Recent reviews (Feachem et?al.; Alonso et?al.) have concluded that in order to have a sustainable impact on the global burden of malaria, it is essential that we knowingly reduce the global incidence of infected persons. To achieve this we must reduce the basic reproductive rate of the parasites to mosquitoes relative to the number of persons, the mosquito/human biting rate, the proportion of mosquitoes carrying infectious sporozoites, the daily survival rate of the infectious mosquito and the ability of malaria-infected persons to infect mosquito vectors. This paper focuses on our understanding of parasite biology underpinning the last of these terms: infection of the mosquito. The article attempts to highlight central issues that require further study to assist in the discovery of useful transmission-blocking measures. PMID:25557077

  10. Reciprocal Trophic Interactions and Transmission of Blood Parasites between Mosquitoes and Frogs

    Directory of Open Access Journals (Sweden)

    Todd G. Smith

    2012-04-01

    Full Text Available The relationship between mosquitoes and their amphibian hosts is a unique, reciprocal trophic interaction. Instead of a one-way, predator-prey relationship, there is a cyclical dance of avoidance and attraction. This has prompted spatial and temporal synchrony between organisms, reflected in emergence time of mosquitoes in the spring and choice of habitat for oviposition. Frog-feeding mosquitoes also possess different sensory apparatuses than do their mammal-feeding counterparts. The reciprocal nature of this relationship is exploited by various blood parasites that use mechanical, salivary or trophic transmission to pass from mosquitoes to frogs. It is important to investigate the involvement of mosquitoes, frogs and parasites in this interaction in order to understand the consequences of anthropogenic actions, such as implementing biocontrol efforts against mosquitoes, and to determine potential causes of the global decline of amphibian species.

  11. Screening of Rubiaceae and Apocynaceae extracts for mosquito larvicidal potential.

    Science.gov (United States)

    Suryawanshi, Rahul; Patil, Chandrashekhar; Borase, Hemant; Narkhede, Chandrakant; Patil, Satish

    2015-01-01

    Rubiaceae and Apocynaceae families are well known for the expression of cyclotides having insecticidal properties. Leaves and flowers extracts of plants from the families Rubiaceae (Ixora coccinea) and Apocynaceae (Allamanda violacea) were evaluated for mosquito larvicidal effect against early IVth instars of Aedes aegypti and Anopheles stephensi. Two forms of plant extracts, one untreated and the other treated with heat and proteolytic enzyme were used for assay. After primary assay, the extract showing more than 50% inhibition was further used for quantification purpose. LC50 and LC90 values of all the extracts were found to be reduced with the treated form. Phytochemical analysis of plant extracts was performed. Primary confirmation for the presence of cyclotides was done by Lowry test, thin layer chromatography and haemolytic assay. This novel approach merits use of plant extracts in mosquito control programmes. PMID:25317964

  12. [Observation on the effectiveness of repellent coating against mosquitoes].

    Science.gov (United States)

    Jiang, Z K; Zhao, X Z; Liu, D P; Ma, Y

    1992-01-01

    The present paper reports on the effectiveness of a repellent coating for the first time. The repellent coating was made by combining DETA (N,N-diethyl-meta-toluamide) with slow-releasing reagent. With this coating employed in the laboratory against Aedes aegypti, the rate of blood-sucking was 3.9-9.5% and the rate of protection was 88.9-95.3% for 1-720 days. During 1-77 days' field trial, the RPI (Relative Population Index) was 0-8.98% in the day-time and 0.74-17.15 during the night-time against Anopheles sinensis, Culex pipiens pallens and Culex tritaeniorhynchus. It is concluded that the repellent coating is effective against mosquitoes, safe and prolongs the protection time following exposure to mosquitoes. PMID:1307278

  13. Inhibition of Anopheles gambiae Odorant Receptor Function by Mosquito Repellents.

    Science.gov (United States)

    Tsitoura, Panagiota; Koussis, Konstantinos; Iatrou, Kostas

    2015-03-20

    The identification of molecular targets of insect repellents has been a challenging task, with their effects on odorant receptors (ORs) remaining a debatable issue. Here, we describe a study on the effects of selected mosquito repellents, including the widely used repellent N,N-diethyl-meta-toluamide (DEET), on the function of specific ORs of the African malaria vector Anopheles gambiae. This study, which has been based on quantitative measurements of a Ca(2+)-activated photoprotein biosensor of recombinant OR function in an insect cell-based expression platform and a sequential compound addition protocol, revealed that heteromeric OR (ORx/Orco) function was susceptible to strong inhibition by all tested mosquito repellents except DEET. Moreover, our results demonstrated that the observed inhibition was due to efficient blocking of Orco (olfactory receptor coreceptor) function. This mechanism of repellent action, which is reported for the first time, is distinct from the mode of action of other characterized insect repellents including DEET. PMID:25657000

  14. Larvicidal activity of neem oil (Azadirachta indica formulation against mosquitoes

    Directory of Open Access Journals (Sweden)

    Dua Virendra K

    2009-06-01

    Full Text Available Abstract Background Mosquitoes transmit serious human diseases, causing millions of deaths every year. Use of synthetic insecticides to control vector mosquitoes has caused physiological resistance and adverse environmental effects in addition to high operational cost. Insecticides of botanical origin have been reported as useful for control of mosquitoes. Azadirachta indica (Meliaceae and its derived products have shown a variety of insecticidal properties. The present paper discusses the larvicidal activity of neem-based biopesticide for the control of mosquitoes. Methods Larvicidal efficacy of an emulsified concentrate of neem oil formulation (neem oil with polyoxyethylene ether, sorbitan dioleate and epichlorohydrin developed by BMR & Company, Pune, India, was evaluated against late 3rd and early 4th instar larvae of different genera of mosquitoes. The larvae were exposed to different concentrations (0.5–5.0 ppm of the formulation along with untreated control. Larvicidal activity of the formulation was also evaluated in field against Anopheles, Culex, and Aedes mosquitoes. The formulation was diluted with equal volumes of water and applied @ 140 mg a.i./m2 to different mosquito breeding sites with the help of pre calibrated knapsack sprayer. Larval density was determined at pre and post application of the formulation using a standard dipper. Results Median lethal concentration (LC50 of the formulation against Anopheles stephensi, Culex quinquefasciatus and Aedes aegypti was found to be 1.6, 1.8 and 1.7 ppm respectively. LC50 values of the formulation stored at 26°C, 40°C and 45°C for 48 hours against Ae. aegypti were 1.7, 1.7, 1.8 ppm while LC90 values were 3.7, 3.7 and 3.8 ppm respectively. Further no significant difference in LC50 and LC90 values of the formulation was observed against Ae. aegypti during 18 months storage period at room temperature. An application of the formulation at the rate of 140 mg a.i./m2 in different breeding sites under natural field conditions provided 98.1% reduction of Anopheles larvae on day 1; thereafter 100% reduction was recorded up to week 1 and more than 80% reduction up to week 3, while percent reduction against Culex larvae was 95.5% on day 1, and thereafter 80% reduction was achieved up to week 3. The formulation also showed 95.1% and, 99.7% reduction of Aedes larvae on day 1 and day 2 respectively; thereafter 100% larval control was observed up to day 7. Conclusion The neem oil formulation was found effective in controlling mosquito larvae in different breeding sites under natural field conditions. As neem trees are widely distributed in India, their formulations may prove to be an effective and eco-friendly larvicide, which could be used as an alternative for malaria control.

  15. Identification of mosquito repellent odours from Ocimum forskolei

    OpenAIRE

    Glinwood Robert; Ghebru Maedot; Ignell Rickard; Dekker Teun; Hopkins Richard

    2011-01-01

    Abstract Background Native mosquito repellent plants have a good potential for integrated mosquito control in local settings. Ocimum forskolei, Lamiaceae, is used in Eritrea as a spatial mosquito repellent inside houses, either through crushing fresh plants or burning dry plants. We verified whether active repellent compounds could be identified using gas-chromatography coupled electroantennogram recordings (GC-EAD) with headspace extracts of crushed plants. Results EAD active compounds inclu...

  16. Larvicidal and mosquito repellent activities of Pine (Pinus longifolia, Family: Pinaceae) oil

    OpenAIRE

    M A Ansari, P. K. Mittal

    2005-01-01

    Background & objectives: Various plant-based products are safe and biodegradable alternatives tosynthetic chemicals for use against mosquitoes. Oil of Pinus longifolia is traditionally used forprotection against mosquitoes in some rural areas but there is no documented report of its use againstmosquitoes. The present study was undertaken to scientifically evaluate the activity of Pine oilagainst mosquitoes.Methods: The oil was procured from the market and its contents were chemically analysed...

  17. Perspectives of people in Mali toward genetically-modified mosquitoes for malaria control

    OpenAIRE

    Famenini Shannon; Traore Mohamed M; Touré Mahamoudou B; Marshall John M; Taylor Charles E

    2010-01-01

    Abstract Background Genetically-modified (GM) mosquitoes have been proposed as part of an integrated vector control strategy for malaria control. Public acceptance is essential prior to field trials, particularly since mosquitoes are a vector of human disease and genetically modified organisms (GMOs) face strong scepticism in developed and developing nations. Despite this, in sub-Saharan Africa, where the GM mosquito effort is primarily directed, very little data is available on perspectives ...

  18. Some environmental and biological factors influencing the activity of entomopathogenic Bacillus on mosquito larvae in Brazil

    Directory of Open Access Journals (Sweden)

    R. A. G. B Consoli

    1995-02-01

    Full Text Available The influence of environmental and biological factors on the efficacy of Bacillus thuringiensis serovar israelensis and B. sphaericus as mosquito larvicides are reviewed. The importance of strain dependence, cultivating media/methods, mosquito species/specificity, formulations and their relation to mosquito feeding habits, as well as temperature, solar exposure, larval density and concomitant presence of other aquatic organisms are addressed with reference to the present status of knowledge in Brazil.

  19. Intrinsic features of Aedes aegypti genes affect transcriptional responsiveness of mosquito genes to dengue virus infection

    OpenAIRE

    Behura, Susanta K.; Severson, David W.

    2012-01-01

    Dengue virus infection causes significant morbidity and mortality in humans world-wide. The Aedes aegypti mosquito is the major vector that spread dengue virus to humans. Interaction between dengue viruses and A. aegypti is a multi-factorial phenomena that is determined by both virus and mosquito genotypes. Although, studies have suggested significant association of mosquito vectorial capacity with population variation of dengue virus, specifications of the vector factors that may influence v...

  20. Relation between HLA genes, human skin volatiles and attractiveness of humans to malaria mosquitoes

    OpenAIRE

    Verhulst, N.O.; Beijleveld, H.; Qiu, Y.T.; Maliepaard, C.A.; Verduyn, W.; Haasnoot, G.W.; Claas, F. H. J.; Mumm, R.; Bouwmeester, H.J.; Takken, W.; Loon van, J.J.A.; Smallegange, R. C.

    2013-01-01

    Chemical cues are considered to be the most important cues for mosquitoes to find their hosts and humans can be ranked for attractiveness to mosquitoes based on the chemical cues they emit. Human leukocyte antigen (HLA) genes are considered to be involved in the regulation of human body odor and may therefore affect human attractiveness to mosquitoes, and hence, affect the force of malaria transmission. In the present study the correlations between HLA profiles, human skin volatiles and human...

  1. An insulin-like peptide regulates egg maturation and metabolism in the mosquito Aedes aegypti

    OpenAIRE

    Brown, Mark R.; Clark, Kevin D.; Gulia, Monika; Zhao, Zhangwu; Garczynski, Stephen F.; Crim, Joe W.; Suderman, Richard J.; Strand, Michael R.

    2008-01-01

    Ingestion of vertebrate blood is essential for egg maturation and transmission of disease-causing parasites by female mosquitoes. Prior studies with the yellow fever mosquito, Aedes aegypti, indicated blood feeding stimulates egg production by triggering the release of hormones from medial neurosecretory cells in the mosquito brain. The ability of bovine insulin to stimulate a similar response further suggested this trigger is an endogenous insulin-like peptide (ILP). A. aegypti encodes eight...

  2. Rationalizing Historical successes of malaria control in Africa in terms of mosquito resource availabilty management

    OpenAIRE

    Killeen, Gerry F.; Seyoum, Aklilu; KNOLS, BART G. J.

    2004-01-01

    Environmental management of mosquito resources is a promising approach with which to control malaria, but it has seen little application in Africa for more than half a century. Here we present a kinetic model of mosquito foraging for aquatic habitats and vertebrate hosts that allows estimation of malaria transmission intensity by defining the availability of these resources as the rate at which individual mosquitoes encounter and use them. The model captures historically observed responses of...

  3. Distribution of Ovary Ecdysteroidogenic Hormone I in the nervous system and gut of mosquitoes

    OpenAIRE

    Brown, Mark R.; Chun Cao

    2001-01-01

    Ovary ecdysteroidogenic hormone I (OEH I) is a gonadotropin in the female mosquito, Aedes aegypti. Whole-mount immunocytochemistry using OEH I antisera revealed an extensive distribution of immunostained cells in larvae and adults of this mosquito comparable to that observed in the African malaria mosquito, Anopheles gambiae. Medial neurosecretory cells were stained in brains of larvae and adult Ae. aegypti. In An gambiae the lateral neurosecretory cells were stained more often. In both speci...

  4. Molecular Xenomonitoring Using Mosquitoes to Map Lymphatic Filariasis after Mass Drug Administration in American Samoa

    OpenAIRE

    Schmaedick, Mark A.; Koppel, Amanda L.; Pilotte, Nils; Torres, Melissa; Williams, Steven A.; Dobson, Stephen L.; Lammie, Patrick J.; Won, Kimberly Y.

    2014-01-01

    Lymphatic filariasis (LF), a mosquito-borne parasitic disease, has been targeted for elimination in many countries since the introduction of mass drug administration (MDA) programs using two-drug combinations along with improved diagnostic methods. Sensitive molecular methods detecting parasite DNA in pools of mosquitoes, along with efficient mosquito collection methods, can help identify sites of continuing LF transmission that may require further treatment after MDA has eliminated transmiss...

  5. THE LARVICIDAL ACTIVITY OF INDIGOFERA ARRECTA LEAF EXTRACT AGAINST CULEX MOSQUITO LARVAE

    Directory of Open Access Journals (Sweden)

    Raheli Neema M, Ojunga M and Ramesh F*

    2014-12-01

    Full Text Available The present study was done to assess the larvicidal activity of the Java indigo plant against the larvae of culex mosquito. The plant leaves were extracted using methanol and water (9:1. After extraction a bioassay was conducted to test its activity in the larva of culex mosquito. The mortality data was subjected to probit analysis to determine the lethal concentration. The Java indigo leaf extract can be used as a natural insecticide control against the Culex mosquito larvae.

  6. Insecticide-Treated Nets Can Reduce Malaria Transmission by Mosquitoes Which Feed Outdoors

    OpenAIRE

    Govella, Nicodem J; Okumu, Fredros O.; Killeen, Gerry F.

    2010-01-01

    Insecticide treated nets (ITNs) represent a powerful means for controlling malaria in Africa because the mosquito vectors feed primarily indoors at night. The proportion of human exposure that occurs indoors, when people are asleep and can conveniently use ITNs, is therefore very high. Recent evidence suggests behavioral changes by malaria mosquito populations to avoid contact with ITNs by feeding outdoors in the early evening. We adapt an established mathematical model of mosquito behavior a...

  7. Interaction between host complement and mosquito-midgut-stage Plasmodium berghei.

    OpenAIRE

    Margos, G.; Navarette, S; Butcher, G.; Davies, A.; Willers, C; Sinden, RE; Lachmann, PJ

    2001-01-01

    After ingestion by mosquitoes, gametocytes of malaria parasites become activated and form extracellular gametes that are no longer protected by the red blood cell membrane against immune effectors of host blood. We have studied the action of complement on Plasmodium developmental stages in the mosquito blood meal using the rodent malaria parasite Plasmodium berghei and rat complement as a model. We have shown that in the mosquito midgut, rat complement components necessary to initiate the alt...

  8. Wolbachia Enhances West Nile Virus (WNV) Infection in the Mosquito Culex tarsalis

    OpenAIRE

    Dodson, Brittany L.; Grant L. Hughes; Paul, Oluwatobi; Matacchiero, Amy C; Kramer, Laura D; Rasgon, Jason L

    2014-01-01

    Novel strategies are required to control mosquitoes and the pathogens they transmit. One attractive approach involves maternally inherited endosymbiotic Wolbachia bacteria. After artificial infection with Wolbachia, many mosquitoes become refractory to infection and transmission of diverse pathogens. We evaluated the effects of Wolbachia (wAlbB strain) on infection, dissemination and transmission of West Nile virus (WNV) in the naturally uninfected mosquito Culex tarsalis, which is an importa...

  9. Some environmental and biological factors influencing the activity of entomopathogenic Bacillus on mosquito larvae in Brazil

    OpenAIRE

    R. A. G. B Consoli; C. J. Carvalho-Pinto; M. A. de Oliveira; B.S. Santos; M. A Lamounier; R. S. A Alves; C. M. B Silva; L. Rabinovitch

    1995-01-01

    The influence of environmental and biological factors on the efficacy of Bacillus thuringiensis serovar israelensis and B. sphaericus as mosquito larvicides are reviewed. The importance of strain dependence, cultivating media/methods, mosquito species/specificity, formulations and their relation to mosquito feeding habits, as well as temperature, solar exposure, larval density and concomitant presence of other aquatic organisms are addressed with reference to the present status of knowledge i...

  10. Some environmental and biological factors influencing the activity of entomopathogenic Bacillus on mosquito larvae in Brazil

    Scientific Electronic Library Online (English)

    R. A. G. B, Consoli; C. J, Carvalho-Pinto; M. A, Oliveira; B. S, Santos; M. A, Lamounier; R. S. A, Alves; C. M. B, Silva; L, Rabinovitch.

    1995-02-01

    Full Text Available The influence of environmental and biological factors on the efficacy of Bacillus thuringiensis serovar israelensis and B. sphaericus as mosquito larvicides are reviewed. The importance of strain dependence, cultivating media/methods, mosquito species/specificity, formulations and their relation to [...] mosquito feeding habits, as well as temperature, solar exposure, larval density and concomitant presence of other aquatic organisms are addressed with reference to the present status of knowledge in Brazil.

  11. Reciprocal Trophic Interactions and Transmission of Blood Parasites between Mosquitoes and Frogs

    OpenAIRE

    Smith, Todd G; Laura V. Ferguson

    2012-01-01

    The relationship between mosquitoes and their amphibian hosts is a unique, reciprocal trophic interaction. Instead of a one-way, predator-prey relationship, there is a cyclical dance of avoidance and attraction. This has prompted spatial and temporal synchrony between organisms, reflected in emergence time of mosquitoes in the spring and choice of habitat for oviposition. Frog-feeding mosquitoes also possess different sensory apparatuses than do their mammal-feeding counterparts. The reciproc...

  12. Ecological Niche Modeling of Potential West Nile Virus Vector Mosquito Species in Iowa

    OpenAIRE

    Larson, Scott R; DeGroote, John P.; Bartholomay, Lyric C.; Sugumaran, Ramanathan

    2010-01-01

    Ecological niche modeling (ENM) algorithms, Maximum Entropy Species Distribution Modeling (Maxent) and Genetic Algorithm for Rule-set Prediction (GARP), were used to develop models in Iowa for three species of mosquito — two significant, extant West Nile virus (WNV) vectors (Culex pipiens L and Culex tarsalis Coquillett (Diptera: Culicidae)), and the nuisance mosquito, Aedes vexans Meigen (Diptera: Culicidae), a potential WNV bridge vector. Occurrence data for the three mosquito species fro...

  13. Limited Dengue Virus Replication in Field-Collected Aedes aegypti Mosquitoes Infected with Wolbachia

    OpenAIRE

    Frentiu, Francesca D.; Zakir, Tasnim; Walker, Thomas; Popovici, Jean; Pyke, Alyssa T.; van den Hurk, Andrew; McGraw, Elizabeth A; O'Neill, Scott L

    2014-01-01

    Almost half of the world's population is at risk of contracting dengue virus, particularly in the tropics and sub-tropics. The virus is transmitted by the mosquito Aedes aegypti, a cosmopolitan species that has proved difficult to control using traditional methods. A new biocontrol strategy has been developed involving the release of mosquitoes infected with Wolbachia bacteria. Mosquitoes with the wMel strain of Wolbachia show dramatically reduced replication and transmission of dengue virus ...

  14. Detection of Porcine Circovirus Type 2 (PCV2) in Mosquitoes from Pig Farms by PCR

    OpenAIRE

    Xiaohong Yang, Lidan Hou, Jing Ye, Qigai He and Shengbo Cao*

    2012-01-01

    To investigate, whether mosquitoes could be potential vectors that maintain or transmit PCV2, 59 mosquito samples were collected from suspicious PCV2-infected pig farms in Hubei and Anhui province, China. Total DNA from these mosquitoes was extracted and then tested for presence of PCV2 nucleic acid by PCR. Four (6.78%) samples showed the positive result. Subsequently, the positive PCR product was cloned into pEASY-T1 vector and sequenced. Sequence analysis displayed that homology between the...

  15. Aedes triseriatus females transovarially-infected with La Crosse virus mate more efficiently than uninfected mosquitoes

    OpenAIRE

    Reese, Sara M; Beaty, Meaghan K; Gabitzsch, Elizabeth S.; Blair, Carol D; Barry J Beaty

    2009-01-01

    The mating efficiencies of field-collected and laboratory-colonized Aedes triseriatus (Say) (Diptera: Culicidae) female mosquitoes transovarially-infected or uninfected with La Crosse virus (LACV) were compared. The females were placed in cages with age-matched males, and the insemination rates were determined daily by detection of sperm in the spermathecae. LACV-infected mosquitoes typically mated more quickly than uninfected mosquitoes. LACV load was not correlated with increased insemination.

  16. Anopheles gambiae Circumsporozoite Protein–Binding Protein Facilitates Plasmodium Infection of Mosquito Salivary Glands

    OpenAIRE

    Wang, Jiuling; Zhang, Yue; Zhao, Yang O.; Li, Michelle W. M.; Zhang, Lili; Dragovic, Srdjan; Abraham, Nabil M.; Fikrig, Erol

    2013-01-01

    Malaria, a mosquito-borne disease caused by Plasmodium species, causes substantial morbidity and mortality throughout the world. Plasmodium sporozoites mature in oocysts formed in the mosquito gut wall and then invade the salivary glands, where they remain until transmitted to the vertebrate host during a mosquito bite. The Plasmodium circumsporozoite protein (CSP) binds to salivary glands and plays a role in the invasion of this organ by sporozoites. We identified an Anopheles salivary gland...

  17. Mosquitoes smell and avoid the insect repellent DEET

    Science.gov (United States)

    Syed, Zainulabeuddin; Leal, Walter S.

    2008-01-01

    The insect repellent DEET is effective against a variety of medically important pests, but its mode of action still draws considerable debate. The widely accepted hypothesis that DEET interferes with the detection of lactic acid has been challenged by demonstrated DEET-induced repellency in the absence of lactic acid. The most recent hypothesis suggests that DEET masks or jams the olfactory system by attenuating electrophysiological responses to 1-octen-3-ol. Our research shows that mosquitoes smell DEET directly and avoid it. We performed single-unit recordings from all functional ORNs on the antenna and maxillary palps of Culex quinquefasciatus and found an ORN in a short trichoid sensillum responding to DEET in a dose-dependent manner. The same ORN responded with higher sensitivity to terpenoid compounds. SPME and GC analysis showed that odorants were trapped in conventional stimulus cartridges upon addition of a DEET-impregnated filter paper strip thus leading to the observed reduced electrophysiological responses, as reported elsewhere. With a new stimulus delivery method releasing equal amounts of 1-octen-3-ol alone or in combination with DEET we found no difference in neuronal responses. When applied to human skin, DEET altered the chemical profile of emanations by a “fixative” effect that may also contribute to repellency. However, the main mode of action is the direct detection of DEET as indicated by the evidence that mosquitoes are endowed with DEET-detecting ORNs and corroborated by behavioral bioassays. In a sugar-feeding assay, both female and male mosquitoes avoided DEET. In addition, mosquitoes responding only to physical stimuli avoided DEET. PMID:18711137

  18. Mosquitoes smell and avoid the insect repellent DEET

    OpenAIRE

    Syed, Zainulabeuddin; Leal, Walter S.

    2008-01-01

    The insect repellent DEET is effective against a variety of medically important pests, but its mode of action still draws considerable debate. The widely accepted hypothesis that DEET interferes with the detection of lactic acid has been challenged by demonstrated DEET-induced repellency in the absence of lactic acid. The most recent hypothesis suggests that DEET masks or jams the olfactory system by attenuating electrophysiological responses to 1-octen-3-ol. Our research shows that mosquitoe...

  19. Elementary school pupils knowledge and attitudes toward butterflies and mosquitoes

    OpenAIRE

    Fakin, Tine

    2012-01-01

    To avoid further loss of biodiversity we should radicly change our antropocentric attitude toward environment. The best way to do this is to instill positive attitudes toward nature to children in school. One of the factors that influences attitude toward nature/organisms is knowledge. The main aim of this study is to find out, whether there are differences in knowledge about, and attitudes toward the “unpopular” mosquito and “popular” butterfly among elementary school students. We focused on...

  20. Genome engineering and gene drive in the mosquito aedes aegypti

    OpenAIRE

    St John, Oliver Tudor Lockhart; Sinkins, Steven; Alphey, Luke

    2012-01-01

    Genetic control strategies are a novel method for reducing populations of pest insects such as the yellow fever mosquito Aedes aegypti, a major vector of several important arboviral diseases. This thesis describes efforts to develop new tools to engineer the Ae. aegypti genome and to better understand existing tools, and furthermore to use these to engineer a gene drive system in Ae. aegypti. The piggyBac transposon was found to be extremely stable in the germline of Ae. aegypti, and transpos...

  1. Interpopulation divergence in competitive interactions of the mosquito Aedes albopictus

    OpenAIRE

    Leisnham, P. T.; Lounibos, L. P.; O’meara, G. F.; Juliano, S. A.

    2009-01-01

    Geographic variation in species interactions can have major effects on distributions. Effects of such variation can be particularly evident for invasive species, in which variation in competitive ability can influence invasive success and impacts. We tested the hypothesis that coexistence or exclusion of the resident mosquito Aedes aegypti results from variation among local populations of the invasive Aedes albopictus in competitive interactions with A. aegypti. We also examined the role of v...

  2. The population dynamics of Plasmodium within the mosquito

    OpenAIRE

    Dawes, Emma J.

    2011-01-01

    Malaria remains one of the world’s most devastating vector-borne parasitic diseases and existing control tools may not be enough to meet the challenge of eliminating malaria in areas of high transmission. Understanding the population dynamics of Plasmodium within the mosquito vector is essential for developing, optimising, and evaluating novel control measures aimed at reducing transmission by targeting this important interface. Malaria research and mathematical models of ...

  3. Origin of the Dengue Fever Mosquito, Aedes aegypti, in California

    OpenAIRE

    Gloria-soria, Andrea; Brown, Julia E.; Kramer, Vicki; Hardstone Yoshimizu, Melissa; Powell, Jeffrey R.

    2014-01-01

    Dengue fever is among the most widespread vector-borne infectious diseases. The primary vector of dengue is the Aedes aegypti mosquito. Ae. aegypti is prevalent in the tropics and sub-tropics and is closely associated with human habitats outside its native range of Africa. While long established in the southeastern United States of America where dengue is re-emerging, breeding populations have never been reported from California until the summer of 2013. Using 12 highly variable microsatellit...

  4. Insight into global mosquito biogeography from country species records.

    Science.gov (United States)

    Foley, Desmond H; Rueda, Leopoldo M; Wilkerson, Richard C

    2007-07-01

    To advance our limited knowledge of global mosquito biogeography, we analyzed country occurrence records from the Systematic Catalog of the Culicidae (http://www.mosquitocatalog. org/main.asp), and we present world maps of species richness and endemism. A latitudinal biodiversity gradient was observed, with species richness increasing toward the equator. A linear log-log species (y)-area (x) relationship (SAR) was found that we used to compare observed and expected species densities for each country. Brazil, Indonesia, Malaysia, and Thailand had the highest numbers of species, and Brazil also had the highest taxonomic output and number of type locations. Brazil, Australia, the Philippines, and Indonesia had the highest numbers of endemic species, but excluding small island countries, Panama, French Guiana, Malaysia, and Costa Rica had the highest densities of total species and endemic species. Globally, 50% of mosquito species are endemic. Island countries had higher total number of species and higher number of endemic species than mainland countries of similar size, but the slope of the SAR was similar for island and mainland countries. Islands also had higher numbers of publications and type locations, possibly due to greater sampling effort and/or species endemism on islands. The taxonomic output was lowest for some countries in Africa and the Middle East. A consideration of country estimates of past sampling effort and species richness and endemism is proposed to guide mosquito biodiversity surveys. For species groups, we show that the number of species of Anopheles subgenus Anopheles varies with those of subgenus Cellia in a consistent manner between countries depending on the region. This pattern is discussed in relation to hypotheses about the historical biogeography and ecology of this medically important genus. Spatial analysis of country species records offers new insight into global patterns of mosquito biodiversity and survey history. PMID:17695008

  5. Heat shock proteins contribute to mosquito dehydration tolerance

    OpenAIRE

    Benoit, Joshua B.; Lopez-Martinez, Giancarlo; Phillips, Zachary P.; Patrick, Kevin R.; DENLINGER, DAVID L.

    2009-01-01

    This study examines the responses of heat shock protein transcripts, Hsp70 and Hsp90, to dehydration stress in three mosquito species, Aedes aegypti, Anopheles gambiae and Culex pipiens. We first defined the water balance attributes of adult females of each species, monitored expression of the hsp transcripts in response to dehydration, and then knocked down expression of the transcripts using RNA interference (RNAi) to evaluate potential functions of the Hsps in maintenance of water balance....

  6. Identification of Wolbachia Strains in Mosquito Disease Vectors

    OpenAIRE

    Osei-Poku, Jewelna; Han, Calvin; Charles M. Mbogo; Jiggins, Francis M.

    2012-01-01

    Wolbachia bacteria are common endosymbionts of insects, and some strains are known to protect their hosts against RNA viruses and other parasites. This has led to the suggestion that releasing Wolbachia-infected mosquitoes could prevent the transmission of arboviruses and other human parasites. We have identified Wolbachia in Kenyan populations of the yellow fever vector Aedes bromeliae and its relative Aedes metallicus, and in Mansonia uniformis and Mansonia africana, which are vectors of ly...

  7. A Physical Map for an Asian Malaria Mosquito, Anopheles stephensi

    OpenAIRE

    Sharakhova, Maria V.; Xia, Ai; Tu, Zhijian; Shouche, Yogesh S.; Unger, Maria F.; Sharakhov, Igor V.

    2010-01-01

    Physical mapping is a useful approach for studying genome organization and evolution as well as for genome sequence assembly. The availability of polytene chromosomes in malaria mosquitoes provides a unique opportunity to develop high-resolution physical maps. We report a 0.6-Mb-resolution physical map consisting of 422 DNA markers hybridized to 379 chromosomal sites of the Anopheles stephensi polytene chromosomes. This makes An. stephensi second only to Anopheles gambiae in density of a phys...

  8. Alkalinization by chloride/bicarbonate pathway in larval mosquito midgut

    OpenAIRE

    Boudko, Dmitri Y.; Moroz, Leonid L.; Harvey, William R.; LINSER, PAUL J.

    2001-01-01

    The midgut of mosquito larvae maintains a specific lumen alkalinization profile with large longitudinal gradients (pH ? 3 units?mm?1) in which an extremely alkaline (pH ? 11) anterior midgut lies between near-neutral posterior midgut and gastric cecum (pH 7–8). A plasma membrane H+ V-ATPase energizes this alkalinization but the ion carriers involved are unknown. Capillary zone electrophoresis of body samples with outlet conductivity detection showed a spe...

  9. Mosquitoes of eastern Amazonian Ecuador: biodiversity, bionomics and barcodes

    Scientific Electronic Library Online (English)

    Yvonne-Marie, Linton; James E, Pecor; Charles H, Porter; Luke Brett, Mitchell; Andres, Garzon-Moreno; Desmond H, Foley; David Brooks, Pecor; Richard C, Wilkerson.

    Full Text Available Two snapshot surveys to establish the diversity and ecological preferences of mosquitoes (Diptera: Culicidae) in the terra firme primary rain forest surrounding the Tiputini Biodiversity Station in the UNESCO Yasuní Biosphere Reserve of eastern Amazonian Ecuador were carried out in November 1998 and [...] May 1999. The mosquito fauna of this region is poorly known; the focus of this study was to obtain high quality link-reared specimens that could be used to unequivocally confirm species level diversity through integrated systematic study of all life stages and DNA sequences. A total of 2,284 specimens were preserved; 1,671 specimens were link-reared with associated immature exuviae, all but 108 of which are slide mounted. This study identified 68 unique taxa belonging to 17 genera and 27 subgenera. Of these, 12 are new to science and 37 comprise new country records. DNA barcodes [658-bp of the mtDNA cytochrome c oxidase ( COI ) I gene] are presented for 58 individuals representing 20 species and nine genera. DNA barcoding proved useful in uncovering and confirming new species and we advocate an integrated systematics approach to biodiversity studies in future. Associated bionomics of all species collected are discussed. An updated systematic checklist of the mosquitoes of Ecuador (n = 179) is presented for the first time in 60 years.

  10. Plasmodium ookinetes coopt mammalian plasminogen to invade the mosquito midgut

    DEFF Research Database (Denmark)

    Ghosh, Anil K; Coppens, Isabelle

    2011-01-01

    Ookinete invasion of the mosquito midgut is an essential step for the development of the malaria parasite in the mosquito. Invasion involves recognition between a presumed mosquito midgut receptor and an ookinete ligand. Here, we show that enolase lines the ookinete surface. An antienolase antibody inhibits oocyst development of both Plasmodium berghei and Plasmodium falciparum, suggesting that enolase may act as an invasion ligand. Importantly, we demonstrate that surface enolase captures plasminogen from the mammalian blood meal via its lysine motif (DKSLVK) and that this interaction is essential for midgut invasion, because plasminogen depletion leads to a strong inhibition of oocyst formation. Although addition of recombinant WT plasminogen to depleted serum rescues oocyst formation, recombinant inactive plasminogen does not, thus emphasizing the importance of plasmin proteolytic activity for ookinete invasion. The results support the hypothesis that enolase on the surface of Plasmodium ookinetes plays a dual role in midgut invasion: by acting as a ligand that interacts with the midgut epithelium and, further, by capturing plasminogen, whose conversion to active plasmin promotes the invasion process.

  11. Susceptibility of adult mosquitoes to insecticides in aqueous sucrose baits.

    Science.gov (United States)

    Allan, Sandra A

    2011-06-01

    Mosquitoes characteristically feed on plant-derived carbohydrates and honeydew just after emergence and intermittently during their lives. Development of toxic baits focusing on this carbohydrate-seeking behavior may potentially contribute to localized control. In the present study, ten insecticides were fed to female Culex quinquefasciatus, Anopheles quadrimaculatus, and Aedes taeniorhynchus in a 10% sucrose solution. Active ingredients representative of five classes of insecticides (pyrethroids, phenylpyroles, pyrroles, neonicotinoids, and macrocyclic lactones) were selected for comparison with commercial formulations used to facilitate incorporation of active ingredients into aqueous sucrose solutions. Sucrose as a phagostimulant significantly enhanced mortality to toxicants. In general, the most effective active ingredients were fipronil, deltamethrin and imidacloprid, followed by spinosad, thiamethoxam, bifenthrin, permethrin, and cyfluthrin. The least effective ingredients were chlorfenapyr and ivermectin. For some of the ingredients tested, Cx. quinquefasciatus was the least susceptible species. One-day-old male Cx. quinquefasciatus were more susceptible than females; however, no differences existed between one- and seven-day-old mosquitoes. There were no differences in susceptibility between unfed and gravid ten-day-old female Cx. quinquefasciatus to bifenthrin. In conclusion, several pesticides from different classes of compounds have potential for use in development of toxic baits for mosquitoes. PMID:21635642

  12. Mosquito (Aedes taeniorhynchus) resistance to methoprene in an isolated habitat.

    Science.gov (United States)

    Dame, D A; Wichterman, G J; Hornby, J A

    1998-06-01

    Salt-marsh mosquitoes (Aedes taeniorhynchus), collected on 2 barrier islands in Lee County, Florida, that had been treated from 1989 to 1994 with 150-day methoprene briquets, were bioassayed with technical s-methoprene in the laboratory. Susceptibility of the indigenous Captiva strain (median lethal concentration [LC50] estimate, 6.71 ppb) collected from Captiva Island was 14.9-fold lower than the naive Flamingo strain (LC50 estimate, 0.45 ppb) from Everglades National Park. The Lover's Key strain (LC50 estimate, 6.66 ppb) was 14.8-fold less susceptible than the naive strain. Determinations of the susceptibility of nearby foci of the mainland mosquitoes exposed in the past several years to methoprene have not been completed, but probit analysis of laboratory exposures revealed that the only mainland strain tested (Burnt Store) was no less susceptible (1.06-fold) than the naive Flamingo strain. These findings support the theory that the observed resistance might be restricted to the barrier islands. The known resistance foci (generated with briquet formulations) are located west of the mainland where there is minimal likelihood of inflow of genome from the mainland. On the other hand, the mainland mosquitoes, which were exposed to liquid formulations of methoprene from 1987 to 1994, are believed to have substantial gene flow between exposed and nonexposed populations and thus a reduced likelihood of selection for resistance. PMID:9673923

  13. Evolution of mosquito-based arbovirus surveillance systems in Australia.

    Science.gov (United States)

    van den Hurk, Andrew F; Hall-Mendelin, Sonja; Johansen, Cheryl A; Warrilow, David; Ritchie, Scott A

    2012-01-01

    Control of arboviral disease is dependent on the sensitive and timely detection of elevated virus activity or the identification of emergent or exotic viruses. The emergence of Japanese encephalitis virus (JEV) in northern Australia revealed numerous problems with performing arbovirus surveillance in remote locations. A sentinel pig programme detected JEV activity, although there were a number of financial, logistical, diagnostic and ethical limitations. A system was developed which detected viral RNA in mosquitoes collected by solar or propane powered CO?-baited traps. However, this method was hampered by trap-component malfunction, microbial contamination and large mosquito numbers which overwhelmed diagnostic capabilities. A novel approach involves allowing mosquitoes within a box trap to probe a sugar-baited nucleic-acid preservation card that is processed for expectorated arboviruses. In a longitudinal field trial, both Ross River and Barmah Forest viruses were detected numerous times from multiple traps over different weeks. Further refinements, including the development of unpowered traps and use of yeast-generated CO?, could enhance the applicability of this system to remote locations. New diagnostic technology, such as next generation sequencing and biosensors, will increase the capacity for recognizing emergent or exotic viruses, while cloud computing platforms will facilitate rapid dissemination of data. PMID:22505808

  14. Temporal abundance of Aedes aegypti in Manaus, Brazil, measured by two trap types for adult mosquitoes

    Science.gov (United States)

    Degener, Carolin Marlen; de Ázara, Tatiana Mingote Ferreira; Roque, Rosemary Aparecida; Codeço, Cláudia Torres; Nobre, Aline Araújo; Ohly, Jörg Johannes; Geier, Martin; Eiras, Álvaro Eduardo

    2014-01-01

    A longitudinal study was conducted in Manaus, Brazil, to monitor changes of adult Aedes aegypti (L.) abundance. The objectives were to compare mosquito collections of two trap types, to characterise temporal changes of the mosquito population, to investigate the influence of meteorological variables on mosquito collections and to analyse the association between mosquito collections and dengue incidence. Mosquito monitoring was performed fortnightly using MosquiTRAPs (MQT) and BG-Sentinel (BGS) traps between December 2008-June 2010. The two traps revealed opposing temporal infestation patterns, with highest mosquito collections of MQTs during the dry season and highest collections of BGS during the rainy seasons. Several meteorological variables were significant predictors of mosquito collections in the BGS. The best predictor was the relative humidity, lagged two weeks (in a positive relationship). For MQT, only the number of rainy days in the previous week was significant (in a negative relationship). The correlation between monthly dengue incidence and mosquito abundance in BGS and MQT was moderately positive and negative, respectively. Catches of BGS traps reflected better the dynamic of dengue incidence. The findings help to understand the effects of meteorological variables on mosquito infestation indices of two different traps for adult dengue vectors in Manaus. PMID:25494470

  15. Analysis of post-blood meal flight distances in mosquitoes utilizing zoo animal blood meals

    OpenAIRE

    Greenberg, Jacob A.; DiMenna, Mark A.; Hanelt, Ben; Hofkin, Bruce V.

    2012-01-01

    We assessed the post-blood meal flight distance of four mosquito species in a unique environment using blood meal analysis. Mosquitoes were trapped at the Rio Grande Zoo in Albuquerque, NM, and the blood source of blood-engorged mosquitoes was identified. The distance from the enclosure of the animal serving as a blood source to the trap site was then determined. We found that mosquitoes captured at the zoo flew no more than 170 m with an average distance of 106.7 m after taking a blood meal....

  16. Intricate predatory decisions by a mosquito-specialist spider from Malaysia.

    Science.gov (United States)

    Jackson, Robert R; Li, Daiqin; Woon, Jeremy R W; Hashim, Rosli; Cross, Fiona R

    2014-10-01

    Paracyrba wanlessi is a southeast Asian jumping spider (Salticidae) that lives in the hollow internodes of fallen bamboo and preys on the larvae, pupae and adults of mosquitoes. In contrast to Evarcha culicivora, an East African salticid that is also known for actively targeting mosquitoes as preferred prey, there was no evidence of P. wanlessi choosing mosquitoes on the basis of species, sex or diet. However, our findings show that P. wanlessi chooses mosquitoes significantly more often than a variety of other prey types, regardless of whether the prey are in or away from water, and regardless of whether the mosquitoes are adults or juveniles. Moreover, a preference for mosquito larvae, pupae and adults is expressed regardless of whether test spiders are maintained on a diet of terrestrial or aquatic prey and regardless of whether the diet includes or excludes mosquitoes. Congruence of an environmental factor (in water versus away from water) with prey type (aquatic versus terrestrial mosquitoes) appeared to be important and yet, even when the prey were in the incongruent environment, P. wanlessi continued to choose mosquitoes more often than other prey. PMID:26064534

  17. Remote Sensing and Modeling of Mosquito Abundance and Habitats in Coastal Virginia, USA

    Directory of Open Access Journals (Sweden)

    A. Scott Bellows

    2011-12-01

    Full Text Available The increase in mosquito populations following extreme weather events poses a major threat to humans because of mosquitoes’ ability to carry disease-causing pathogens, particularly in low-lying, poorly drained coastal plains vulnerable to tropical cyclones. In areas with reservoirs of disease, mosquito abundance information can help to identify the areas at higher risk of disease transmission. Using a Geographic Information System (GIS, mosquito abundance is predicted across the City of Chesapeake, Virginia. The mosquito abundance model uses mosquito light trap counts, a habitat suitability model, and dynamic environmental variables (temperature and precipitation to predict the abundance of the species Culiseta melanura, as well as the combined abundance of the ephemeral species, Aedes vexans and Psorophora columbiae, for the year 2003. Remote sensing techniques were used to quantify environmental variables for a potential habitat suitability index for the mosquito species. The goal of this study was to produce an abundance model that could guide risk assessment, surveillance, and potential disease transmission. Results highlight the utility of integrating field surveillance, remote sensing for synoptic landscape habitat distributions, and dynamic environmental data for predicting mosquito vector abundance across low-lying coastal plains. Limitations of mosquito trapping and multi-source geospatial environmental data are highlighted for future spatial modeling of disease transmission risk.

  18. Molecular Epidemiology of Japanese Encephalitis Virus in Mosquitoes in Taiwan during 2005–2012

    OpenAIRE

    Su, Chien-Ling; Yang, Cheng-Fen; Teng, Hwa-Jen; Lu, Liang-Chen; Lin, Cheo; Tsai, Kun-Hsien; Chen, Yu-Yu; Chen, Li-Yu; Chang, Shu-Fen; Shu, Pei-Yun

    2014-01-01

    Japanese encephalitis (JE) is a mosquito-borne zoonotic disease caused by the Japanese encephalitis virus (JEV). Pigs and water birds are the main amplifying and maintenance hosts of the virus. In this study, we conducted a JEV survey in mosquitoes captured in pig farms and water bird wetland habitats in Taiwan during 2005 to 2012. A total of 102,633 mosquitoes were collected. Culex tritaeniorhynchus was the most common mosquito species found in the pig farms and wetlands. Among the 26 mosqui...

  19. Surveillance of mosquitoes in some selected parks and gardens of Dhaka city, Bangladesh.

    Directory of Open Access Journals (Sweden)

    Kabirul Bashar

    2014-03-01

    Full Text Available A yearlong (Jul-10 to June-11 intensive survey was conducted to document the diversity and density of different mosquito species, breeding habitats and their status at different park in Dhaka city. A total of 11 species of mosquito were identified from the six study areas. The recorded species were An. annularis, An. culicifacies, Ae. albopictus, Ae. aegypti, Ar. subalbatus, Cx. fuscocephala, Cx. quinquefasciatus, Cx. tritaeniorhynchus, Mn. annulifera, Mn. uniformis, Tx. splendidus. Aedes albopictus (38.18% and Ar. subalbatus (37.47% were the predominant mosquito species followed by Cx. quinquefasciatus. Others species were found in moderate percentage. Lowest density of Cx. fuscocephala (0.6% was recorded among the collected mosquito species from the different study area. The highest percentages of mosquito were found in Botanical garden (28.68% followed by Ramna park, Zia uddyan, Baldha garden, Suhrawardy uddyan, and Osmani uddyan (6.67%. Fifteen different larval habitats were found in the study areas. Majority of the mosquito species was found to breed in pond. High density of Ae. albopictus mosquito were found in all study areas, which is the secondary vector of dengue viruses. Principal dengue vector mosquito, Ae. aegypti were found only in Baldha garden. Ar. subalbatus was also a dominant mosquito species in the entire site.

  20. Mosquito-host interactions during and after an outbreak of equine viral encephalitis in Eastern Panama.

    Science.gov (United States)

    Navia-Gine, Wayra G; Loaiza, Jose R; Miller, Matthew J

    2013-01-01

    Mosquito blood meals provide information about the feeding habits and host preference of potential arthropod-borne disease vectors. Although mosquito-borne diseases are ubiquitous in the Neotropics, few studies in this region have assessed patterns of mosquito-host interactions, especially during actual disease outbreaks. Based on collections made during and after an outbreak of equine viral encephalitis, we identified the source of 338 blood meals from 10 species of mosquitoes from Aruza Abajo, a location in Darien province in eastern Panama. A PCR based method targeting three distinct mitochondrial targets and subsequent DNA sequencing was used in an effort to delineate vector-host relationships. At Aruza Abajo, large domesticated mammals dominated the assemblage of mosquito blood meals while wild bird and mammal species represented only a small portion of the blood meal pool. Most mosquito species fed on a variety of hosts; foraging index analysis indicates that eight of nine mosquito species utilize hosts at similar proportions while a stochastic model suggests dietary overlap among species was greater than would be expected by chance. The results from our null-model analysis of mosquito diet overlap are consistent with the hypothesis that in landscapes where large domestic animals dominate the local biomass, many mosquito species show little host specificity, and feed upon hosts in proportion to their biomass, which may have implications for the role of livestocking patterns in vector-borne disease ecology. PMID:24339965

  1. Temporal abundance of Aedes aegypti in Manaus, Brazil, measured by two trap types for adult mosquitoes

    Scientific Electronic Library Online (English)

    Carolin Marlen, Degener; Tatiana Mingote Ferreira de, Ázara; Rosemary Aparecida, Roque; Cláudia Torres, Codeço; Aline Araújo, Nobre; Jörg Johannes, Ohly; Martin, Geier; Álvaro Eduardo, Eiras.

    1030-10-01

    Full Text Available A longitudinal study was conducted in Manaus, Brazil, to monitor changes of adult Aedes aegypti (L.) abundance. The objectives were to compare mosquito collections of two trap types, to characterise temporal changes of the mosquito popu [...] lation, to investigate the influence of meteorological variables on mosquito collections and to analyse the association between mosquito collections and dengue incidence. Mosquito monitoring was performed fortnightly using MosquiTRAPs (MQT) and BG-Sentinel (BGS) traps between December 2008-June 2010. The two traps revealed opposing temporal infestation patterns, with highest mosquito collections of MQTs during the dry season and highest collections of BGS during the rainy seasons. Several meteorological variables were significant predictors of mosquito collections in the BGS. The best predictor was the relative humidity, lagged two weeks (in a positive relationship). For MQT, only the number of rainy days in the previous week was significant (in a negative relationship). The correlation between monthly dengue incidence and mosquito abundance in BGS and MQT was moderately positive and negative, respectively. Catches of BGS traps reflected better the dynamic of dengue incidence. The findings help to understand the effects of meteorological variables on mosquito infestation indices of two different traps for adult dengue vectors in Manaus.

  2. Epoxide hydrolase activities and epoxy fatty acids in the mosquito Culex quinquefasciatus.

    Science.gov (United States)

    Xu, Jiawen; Morisseau, Christophe; Yang, Jun; Mamatha, Dadala M; Hammock, Bruce D

    2015-04-01

    Culex mosquitoes have emerged as important model organisms for mosquito biology, and are disease vectors for multiple mosquito-borne pathogens, including West Nile virus. We characterized epoxide hydrolase activities in the mosquito Culex quinquefasciatus, which suggested multiple forms of epoxide hydrolases were present. We found EH activities on epoxy eicosatrienoic acids (EETs). EETs and other eicosanoids are well-established lipid signaling molecules in vertebrates. We showed EETs can be synthesized in vitro from arachidonic acids by mosquito lysate, and EETs were also detected in vivo both in larvae and adult mosquitoes by LC-MS/MS. The EH activities on EETs can be induced by blood feeding, and the highest activity was observed in the midgut of female mosquitoes. The enzyme activities on EETs can be inhibited by urea-based inhibitors designed for mammalian soluble epoxide hydrolases (sEH). The sEH inhibitors have been shown to play diverse biological roles in mammalian systems, and they can be useful tools to study the function of EETs in mosquitoes. Besides juvenile hormone metabolism and detoxification, insect epoxide hydrolases may also play a role in regulating lipid signaling molecules, such as EETs and other epoxy fatty acids, synthesized in vivo or obtained from blood feeding by female mosquitoes. PMID:25686802

  3. Nature, Nurture and Evolution of Intra-Species Variation in Mosquito Arbovirus Transmission Competence

    Directory of Open Access Journals (Sweden)

    Walter J. Tabachnick

    2013-01-01

    Full Text Available Mosquitoes vary in their competence or ability to transmit arthropod-borne viruses (arboviruses. Many arboviruses cause disease in humans and animals. Identifying the environmental and genetic causes of variation in mosquito competence for arboviruses is one of the great challenges in public health. Progress identifying genetic (nature and environmental (nurture factors influencing mosquito competence for arboviruses is reviewed. There is great complexity in the various traits that comprise mosquito competence. The complex interactions between environmental and genetic factors controlling these traits and the factors shaping variation in Nature are largely unknown. The norms of reaction of specific genes influencing competence, their distributions in natural populations and the effects of genetic polymorphism on phenotypic variation need to be determined. Mechanisms influencing competence are not likely due to natural selection because of the direct effects of the arbovirus on mosquito fitness. More likely the traits for mosquito competence for arboviruses are the effects of adaptations for other functions of these competence mechanisms. Determining these other functions is essential to understand the evolution and distributions of competence for arboviruses. This information is needed to assess risk from mosquito-borne disease, predict new mosquito-arbovirus systems, and provide novel strategies to mitigate mosquito-borne arbovirus transmission.

  4. Molecular Epidemiology of Japanese Encephalitis Virus in Mosquitoes during an Outbreak in China, 2013

    OpenAIRE

    Zexin Tao; Guifang Liu; Min Wang; Huanyu Wang; Xiaojuan Lin; Lizhi Song; Suting Wang; Haiyan Wang; Xiaodong Liu; Ning Cui; Yanyan Song; Aiqiang Xu

    2014-01-01

    Japanese encephalitis virus (JEV) can cause serious encephalitis and Culex mosquitoes are the primary vector. In 2013, a JE outbreak occurred in Shandong Province, China with 407 confirmed cases, including 11 deaths. An investigation on JEV in mosquitoes during the outbreak was conducted. A total of 14,719 mosquitoes were collected at 3 sites. For the 12,695 Culex tritaeniorhynchus mosquitoes, 88/201 pooled samples were positive by RT-PCR for the presence of the pre-membrane or envelope pr...

  5. The Role of Innate Immunity in Conditioning Mosquito Susceptibility to West Nile Virus

    Directory of Open Access Journals (Sweden)

    Abhishek N. Prasad

    2013-12-01

    Full Text Available Arthropod-borne viruses (arboviruses represent an emerging threat to human and livestock health globally. In particular, those transmitted by mosquitoes present the greatest challenges to disease control efforts. An understanding of the molecular basis for mosquito innate immunity to arbovirus infection is therefore critical to investigations regarding arbovirus evolution, virus-vector ecology, and mosquito vector competence. In this review, we discuss the current state of understanding regarding mosquito innate immunity to West Nile virus. We draw from the literature with respect to other virus-vector pairings to attempt to draw inferences to gaps in our knowledge about West Nile virus and relevant vectors.

  6. Mosquitos Culicidae como vetores emergentes de infecções Culicidae mosquitoes as emerging vectors of diseases

    Directory of Open Access Journals (Sweden)

    Oswaldo Paulo Forattini

    1998-12-01

    Full Text Available Apresenta-se sucinta revisão do relacionamento entre as chamadas infecções emergentes e o conceito de vetores emergentes. Estes são entendidos não apenas no que concerne aos que são descritos como tais, de forma nova, mas também aqueles com acentuadas mudanças de comportamento. Os fatores específicos que propiciam esse fenômeno identificam-se à poderosa influência humana sobre o ambiente. Assim, aquele construído pelo homem e conhecido como antrópico representa a função de pressão seletiva que induz as populações vetoras a se adaptarem às novas circunstâncias. Nelas inclui-se fatores ecológicos ambientais, ou demográficos, que incrementam o contato com os novos comportamentos vetoriais. Relata-se o encontro de criadouros anômalos de mosquitos Culicidae nas Américas. A interpretação desses encontros é feita visando à vigilância epidemiológica. O significado dessa emergência ou reemergência pode se traduzir no aparecimento de problemas epidemiológicos. Sugere-se que, em sendo assim, a vigilância epidemiológica deva ser feita em grau global.A review is presented of the relationships between the so-called emerging infectious diseases and what may be defined as emerging vectors. These include not only those that have recently appeared but also those that present remarkable behavioral changes. Specific factors leading to that emergence can be associated with the powerful human influence on the environment. So the man-made, i.e. anthropic environment, exercises a selective pressure inducing vector populations to adapt to new circumstances. These may arise from ecological, environmental, or demographic factors that increase contact with the new vector. With this in mind, data on anomalous Culicidae breeding places in the Americas are reported. An interpretation of these findings is offered in the light of epidemiological surveillance. The question is whether vector emergence or re-emergence may constitute an epidemiological problem. Thus it is suggested that plane for all inclusive surveillance be prepared.

  7. Mosquito population dynamic (diptera: culicidae in a eutrophised dam Dinâmica populacional de mosquitos em açude eutrofizado

    Directory of Open Access Journals (Sweden)

    ED. Wermelinger

    2012-11-01

    Full Text Available This study observed the mosquito population in a rural eutrophised dam. Larvae of L3 and L4 stages and pupae were dipped out during twelve month collections and the reared to the adult stage for identification. The collections were done along nine metres from the edge of the dam divided in three parts (P1, P2 and P3, each part being 3 m long. P1 did not have vegetation (grass along its edge,which would reach or sink into the water to promote some shade on the marginal water. A total of 217 adults of four species was identified with the following constancies and frequencies: Culex quinquefasciatus (Say, 1823 (83% and 40.6%, Anopheles (Nyssorhynchus evansae (Brèthes, 1926 (92% and 26.7%, Anopheles (Nyssorhynchus rangeli (Gabaldon, Cova Garcia and Lopez, 1940 (83% and 14.3% and Culex nigripalpus (Theobald, 1901 (33% and 18.4%. C. quinquefasciatus, A. evansae, A. rangeli and C. nigripalpus were more frequent in the quarters Nov./Dec./Jan. (85.7%, May/June/July (75%, Aug./Sept./Oct. (29.4% and Aug./Sept./Oct. (23.5% particularly in the months of December (88.4% Sept.tember (48.94, (38.3 and August (47.62 respectively. The presence of C. quinquefasciatus and the high incidence of Daphinia sp. and also the levels of Organic Nitrogen (0.28 mg/L and of total Phosphorus (0.02 mg/L are indications of the eutrophication of the dam. There was a difference regarding the total of Anopheles (A. avansae + A. rangeli and Culex species (C. quinquefasciatus + C. nigripalpis between P1 and P2 (?² = 0.0097, P1 and P3 (?² = 0.0005, but not between P2 and P3 (?² = 0.2045.The high C. quinquefasciatus constancy and frequency were confirmed to be a good biological indicator for a eutrophised environment and A. evansae showed a good potential for this environment. Vegetation can be an important factor for anopheline population dynamic also in eutrophic breeding sites.Este estudo observou a dinâmica populacional dos mosquitos em açude eutrofizado na área rural de Paraíba do Sul, Estado do Rio de Janeiro. Foram realizadas 12 coletas mensais de mosquitos imaturos pelo método da conchada em 9 m de borda, divididos em três postos (P1, P2 e P3, com 3 m de extensão cada. O posto P1 difere por não ter vegetação (capim, mato na margem, alcançando ou penetrando e promovendo alguma sombra na água. Larvas L3, L4 e pupas foram isoladas para a obtenção dos adultos e identificação. Foram identificados 217 espécimes adultos de quatro espécies, com as seguintes constâncias e frequências: Culex quinquefasciatus (Say, 1823 (83% e 40,6%, Anopheles (Nyssorhynchus evansae (Brèthes, 1926 (92% e 26,7%, Anopheles (Nyssorhynchus rangeli (Gabaldon, Cova Garcia e Lopez, 1940 (83% e 14,3% e Culex nigripalpus (Theobald, 1901 (33% e 18,4%, com maiores frequências nos trimestres nov./dez./jan. (85,7%, maio/jun./jul. (75%, ago./set./out. (29,4%, ago./set./out. (23,5% e, nos meses dezembro (88,4%, setembro (48,94, (38,3 e agosto (47,62, respectivamente. A presença do Culex quinquefasciatus (40% e a elevada incidência de Daphinia sp., juntamente com os níveis de Nitrogênio orgânico (0,28 mg/L e de Fósforo total (0,02 mg/L, indicam a eutrofização do açude. Houve diferença comparando os totais de anofelinos (A. avansae + A. rangeli com os totais de culicini (C. quinquefasciatus + C. nigripalpis entre P1 e P2 (?² = 0,0097, e entre P1 para P3 (?² = 0,0005, mas não entre P2 e P3 (?² = 0,2045. A elevada frequência e a constância de C. quinquefasciatus confirmam esta ser uma boa espécie bioindicadora para ambientes eutrofizados e A. evansae apresentou boa potencialidade nesse nível trófico. A vegetação pode influir na dinâmica populacional dos anofelinos também em ambientes eutróficos.

  8. Mosquito population dynamic (diptera: culicidae) in a eutrophised dam / Dinâmica populacional de mosquitos em açude eutrofizado

    Scientific Electronic Library Online (English)

    ED., Wermelinger; CV., Benigno; RNM., Machado; PH., Cabello; AM., Meira; AP., Ferreira; JC., Zanuncio.

    2012-11-01

    Full Text Available Este estudo observou a dinâmica populacional dos mosquitos em açude eutrofizado na área rural de Paraíba do Sul, Estado do Rio de Janeiro. Foram realizadas 12 coletas mensais de mosquitos imaturos pelo método da conchada em 9 m de borda, divididos em três postos (P1, P2 e P3), com 3 m de extensão ca [...] da. O posto P1 difere por não ter vegetação (capim, mato) na margem, alcançando ou penetrando e promovendo alguma sombra na água. Larvas L3, L4 e pupas foram isoladas para a obtenção dos adultos e identificação. Foram identificados 217 espécimes adultos de quatro espécies, com as seguintes constâncias e frequências: Culex quinquefasciatus (Say, 1823) (83% e 40,6%), Anopheles (Nyssorhynchus) evansae (Brèthes, 1926) (92% e 26,7%), Anopheles (Nyssorhynchus) rangeli (Gabaldon, Cova Garcia e Lopez, 1940) (83% e 14,3%) e Culex nigripalpus (Theobald, 1901) (33% e 18,4%), com maiores frequências nos trimestres nov./dez./jan. (85,7%), maio/jun./jul. (75%), ago./set./out. (29,4%), ago./set./out. (23,5%) e, nos meses dezembro (88,4%), setembro (48,94), (38,3) e agosto (47,62), respectivamente. A presença do Culex quinquefasciatus (40%) e a elevada incidência de Daphinia sp., juntamente com os níveis de Nitrogênio orgânico (0,28 mg/L) e de Fósforo total (0,02 mg/L), indicam a eutrofização do açude. Houve diferença comparando os totais de anofelinos (A. avansae + A. rangeli) com os totais de culicini (C. quinquefasciatus + C. nigripalpis) entre P1 e P2 (?² = 0,0097), e entre P1 para P3 (?² = 0,0005), mas não entre P2 e P3 (?² = 0,2045). A elevada frequência e a constância de C. quinquefasciatus confirmam esta ser uma boa espécie bioindicadora para ambientes eutrofizados e A. evansae apresentou boa potencialidade nesse nível trófico. A vegetação pode influir na dinâmica populacional dos anofelinos também em ambientes eutróficos. Abstract in english This study observed the mosquito population in a rural eutrophised dam. Larvae of L3 and L4 stages and pupae were dipped out during twelve month collections and the reared to the adult stage for identification. The collections were done along nine metres from the edge of the dam divided in three par [...] ts (P1, P2 and P3), each part being 3 m long. P1 did not have vegetation (grass) along its edge,which would reach or sink into the water to promote some shade on the marginal water. A total of 217 adults of four species was identified with the following constancies and frequencies: Culex quinquefasciatus (Say, 1823) (83% and 40.6%), Anopheles (Nyssorhynchus) evansae (Brèthes, 1926) (92% and 26.7%), Anopheles (Nyssorhynchus) rangeli (Gabaldon, Cova Garcia and Lopez, 1940) (83% and 14.3%) and Culex nigripalpus (Theobald, 1901) (33% and 18.4%). C. quinquefasciatus, A. evansae, A. rangeli and C. nigripalpus were more frequent in the quarters Nov./Dec./Jan. (85.7%), May/June/July (75%), Aug./Sept./Oct. (29.4%) and Aug./Sept./Oct. (23.5%) particularly in the months of December (88.4%) Sept.tember (48.94), (38.3) and August (47.62) respectively. The presence of C. quinquefasciatus and the high incidence of Daphinia sp. and also the levels of Organic Nitrogen (0.28 mg/L) and of total Phosphorus (0.02 mg/L) are indications of the eutrophication of the dam. There was a difference regarding the total of Anopheles (A. avansae + A. rangeli) and Culex species (C. quinquefasciatus + C. nigripalpis) between P1 and P2 (?² = 0.0097), P1 and P3 (?² = 0.0005), but not between P2 and P3 (?² = 0.2045).The high C. quinquefasciatus constancy and frequency were confirmed to be a good biological indicator for a eutrophised environment and A. evansae showed a good potential for this environment. Vegetation can be an important factor for anopheline population dynamic also in eutrophic breeding sites.

  9. Optimización de un procedimiento de extracción de ADN para mosquitos anofelinos Optimization of a DNA extraction procedure for anopheline mosquitoes

    Directory of Open Access Journals (Sweden)

    DORIS A ROSERO

    2010-12-01

    Full Text Available Se optimizó un protocolo para la extracción de ADN a partir de mosquitos anofelinos, evaluando varios tiempos de incubación de la muestra con el acetato de potasio (AcK. Los resultados evidenciaron que la mayor concentración de ADN y frecuencia de amplificación se obtuvieron al utilizar el tratamiento de 1 h, lo que sugiere que es posible reducir el tiempo de incubación con AcK sin afectar la cantidad y calidad del ADN extraído.A DNA extraction protocol for anopheline mosquitoes was optimized by the evaluation of various incubation times of the sample with Potassium acetate (KAc. The results showed that the highest DNA concentration and amplification frequency were obtained with the 1 h treatment, which suggests that is possible to reduce the incubation time with KAc without affecting the amount and quality of the DNA extracted.

  10. Optimización de un procedimiento de extracción de ADN para mosquitos anofelinos / Optimization of a DNA extraction procedure for anopheline mosquitoes

    Scientific Electronic Library Online (English)

    DORIS A, ROSERO; LINA A, GUTIÉRREZ; ASTRID V, CIENFUEGOS; LUZ M, JARAMILLO; MARGARITA M, CORREA.

    2010-12-01

    Full Text Available Se optimizó un protocolo para la extracción de ADN a partir de mosquitos anofelinos, evaluando varios tiempos de incubación de la muestra con el acetato de potasio (AcK). Los resultados evidenciaron que la mayor concentración de ADN y frecuencia de amplificación se obtuvieron al utilizar el tratamie [...] nto de 1 h, lo que sugiere que es posible reducir el tiempo de incubación con AcK sin afectar la cantidad y calidad del ADN extraído. Abstract in english A DNA extraction protocol for anopheline mosquitoes was optimized by the evaluation of various incubation times of the sample with Potassium acetate (KAc). The results showed that the highest DNA concentration and amplification frequency were obtained with the 1 h treatment, which suggests that is p [...] ossible to reduce the incubation time with KAc without affecting the amount and quality of the DNA extracted.

  11. Mosquitoes Put the Brake on Arbovirus Evolution: Experimental Evolution Reveals Slower Mutation Accumulation in Mosquito Than Vertebrate Cells

    OpenAIRE

    Vasilakis, Nikos; Deardorff, Eleanor R.; Kenney, Joan L.; Rossi, Shannan L.; Hanley, Kathryn A.; Weaver, Scott C.

    2009-01-01

    Like other arthropod-borne viruses (arboviruses), mosquito-borne dengue virus (DENV) is maintained in an alternating cycle of replication in arthropod and vertebrate hosts. The trade-off hypothesis suggests that this alternation constrains DENV evolution because a fitness increase in one host usually diminishes fitness in the other. Moreover, the hypothesis predicts that releasing DENV from host alternation should facilitate adaptation. To test this prediction, DENV was serially passaged in e...

  12. Evaluation of PermaNet 3.0 a deltamethrin-PBO combination net against Anopheles gambiae and pyrethroid resistant Culex quinquefasciatus mosquitoes: an experimental hut trial in Tanzania

    Directory of Open Access Journals (Sweden)

    Malima Robert

    2010-01-01

    Full Text Available Abstract Background Combination mosquito nets incorporating two unrelated insecticides or insecticide plus synergist are designed to control insecticide resistant mosquitoes. PermaNet 3.0 is a long-lasting combination net incorporating deltamethrin on the side panels and a mixture of deltamethrin and synergist piperonyl butoxide (PBO on the top panel. PBO is an inhibitor of mixed function oxidases implicated in pyrethroid resistance. Method An experimental hut trial comparing PermaNet 3.0, PermaNet 2.0 and a conventional deltamethrin-treated net was conducted in NE Tanzania using standard WHOPES procedures. The PermaNet arms included unwashed nets and nets washed 20 times. PermaNet 2.0 is a long-lasting insecticidal net incorporating deltamethrin as a single active. Results Against pyrethroid susceptible Anopheles gambiae the unwashed PermaNet 3.0 showed no difference to unwashed PermaNet 2.0 in terms of mortality (95% killed, but showed differences in blood-feeding rate (3% blood-fed with PermaNet 3.0 versus 10% with PermaNet 2.0. After 20 washes the two products showed no difference in feeding rate (10% with 3.0 and 9% with 2.0 but showed small differences in mortality (95% with 3.0 and 87% with 2.0. Against pyrethroid resistant Culex quinquefasciatus, mediated by elevated oxidase and kdr mechanisms, the unwashed PermaNet 3.0 killed 48% and PermaNet 2.0 killed 32% but after 20 washes there was no significant difference in mortality between the two products (32% killed by 3.0 and 30% by 2.0. For protecting against Culex PermaNet 3.0 showed no difference to PermaNet 2.0 when either unwashed or after 20 washes; both products were highly protective against biting. Laboratory tunnel bioassays confirmed the loss of biological activity of the PBO/deltamethrin-treated panel after washing. Conclusion Both PermaNet products were highly effective against susceptible Anopheles gambiae. As a long-lasting net to control or protect against pyrethroid resistant mosquitoes PermaNet 3.0 showed limited improvement over PermaNet 2.0 against Culex quinquefasciatus.

  13. The mosquitoes of Quintana Roo State, Mexico (Diptera: Culicidae) / Los mosquitos del estado de Quintana Roo, México (Diptera: Culicidae)

    Scientific Electronic Library Online (English)

    Aldo I., ORTEGA MORALES; Pedro, MIS AVILA; Armando, ELIZONDO-QUIROGA; Ralph E., HARBACH; Quetzaly K., SILLER-RODRÍGUEZ; Ildefonso, FERNÁNDEZ-SALAS.

    2010-04-01

    Full Text Available Un estudio de la distribución de los mosquitos del estado de Quintana Roo, México fue realizado por medio de colectas de estados inmaduros y adultos durante Septiembre y Octubre del 2006. Las colectas fueron realizadas en diferentes localidades de las tres provincias fisiográficas del estado: Carso [...] Yucateco, Carso, Lomeríos de Campeche y Costa Baja de Quintana Roo. Un total de 420 larvas, 294 pupas y 726 adultos fueron colectados representando 13 géneros y 41 especies. Dos géneros, tres subgéneros y 11 especies son nuevos registros estatales para Quintana Roo. Abstract in english A study on the distribution of the mosquitoes of Quintana Roo State of México was carried out by collecting immature and adult stages during September and October 2006. The collections were made from different locations in the three physiogeographical provinces of the state: Carso Yucateco, Carso, L [...] omeríos de Campeche, and Costa Baja de Quintana Roo. A total of 420 larvae, 294 pupae, and 726 adults representing 13 genera and 41 species were collected. Two genera, three subgenera, and 11 species are new to the mosquito fauna of Quintana Roo State. Collection and bionomical data are included for species collected during the study, and a checklist of species newly and previously recorded from the state is provided.

  14. Essential oils of Cupressus funebris, Juniperus communis, and J. chinensis (Cupressaceae) as repellents against ticks (Acari: Ixodidae) and mosquitoes (Diptera: Culicidae) and as toxicants against mosquitoes.

    Science.gov (United States)

    Carroll, John F; Tabanca, Nurhayat; Kramer, Matthew; Elejalde, Natasha M; Wedge, David E; Bernier, Ulrich R; Coy, Monique; Becnel, James J; Demirci, Betul; Ba?er, Kemal Husnu Can; Zhang, Jian; Zhang, Sui

    2011-12-01

    Juniperus communis leaf oil, J. chinensis wood oil, and Cupressus funebris wood oil (Cupressaceae) from China were analyzed by gas chromatography and gas chromatography-mass spectrometry. We identified 104 compounds, representing 66.8-95.5% of the oils. The major components were: ?-pinene (27.0%), ?-terpinene (14.0%), and linalool (10.9%) for J. communis; cuparene (11.3%) and ?-cadinene (7.8%) for J. chinensis; and ?-cedrene (16.9%), cedrol (7.6%), and ?-cedrene (5.7%) for C. funebris. The essential oils of C. funebris, J. chinensis, and J. communis were evaluated for repellency against adult yellow fever mosquitoes, Aedes aegypti (L.), host-seeking nymphs of the lone star tick, Amblyomma americanum (L.), and the blacklegged tick, Ixodes scapularis Say, and for toxicity against Ae. aegypti larvae and adults, all in laboratory bioassays. All the oils were repellent to both species of ticks. The EC(95) values of C. funebris, J. communis, and J. chinensis against A. americanum were 0.426, 0.508, and 0.917 mg oil/cm(2) filter paper, respectively, compared to 0.683 mg deet/cm(2) filter paper. All I. scapularis nymphs were repelled by 0.103 mg oil/cm(2) filter paper of C. funebris oil. At 4 h after application, 0.827 mg oil/cm(2) filter paper, C. funebris and J. chinensis oils repelled ?80% of A. americanum nymphs. The oils of C. funebris and J. chinensis did not prevent female Ae. aegypti from biting at the highest dosage tested (1.500 mg/cm(2) ). However, the oil of J. communis had a Minimum Effective Dosage (estimate of ED(99) ) for repellency of 0.029 ± 0.018 mg/cm(2) ; this oil was nearly as potent as deet. The oil of J. chinensis showed a mild ability to kill Ae. aegypti larvae, at 80 and 100% at 125 and 250 ppm, respectively. PMID:22129397

  15. Mosquitoes of the rice agroecosystem of Malaysia: species composition and their abundance in relation to rice farming

    International Nuclear Information System (INIS)

    Mosquito abundance in relation to rice farming was studied in the Muda and the Kerian Irrigation Schemes. Mosquito larvae were collected using dippers for several growing seasons. Adult mosquitoes were collected by using human bait and cow bait and net trap at nights. Culex, Mansonia and Anopheles were the three genera of mosquito found in the rice agroecosystem. Four species of Mansonia were found biting on human bait. Culex mosquitoes were caught biting on human and cow baits. Culex tritaeniorhynchus, C pseudovishnui, C vishnui, C gelidus and C bitaeniorhynchus were the most common Culex mosquitoes found. Anoheles sinensis and A. peditaeniatus were the most dominant panopheline mosquitoes. High abundance of larvae and adult mosquitoes were observed during ploughing, planting, and tillering stages of rice farming. (Author)

  16. Killing and Noether Symmetries of Plane Symmetric Spacetime

    CERN Document Server

    Shamir, M Farasat; Bhatti, Akhlaq Ahmad

    2015-01-01

    This paper is devoted to investigate the Killing and Noether symmetries of static plane symmetric spacetime. For this purpose, five different cases have been discussed. The Killing and Noether symmetries of Minkwoski spacetime in cartesian coordinates are calculated as a special case and it is found that Lie algebra of the Lagrangian is 10 and 17 dimensional respectively. The symmetries of Taub's universe, anti-deSitter universe, self similar solutions of in?finite kind for parallel perfect fluid case and self similar solutions of infinite kind for parallel dust case are also explored. In all the cases, the Noether generators are calculated in the presence of gauge term. All these examples justify the conjecture that Killing symmetries form a subalgebra of Noether symmetries [1].

  17. Inflatable kill packers used in working over Kuwaiti wells

    International Nuclear Information System (INIS)

    This paper reports on inflatable packers which are being used with great success in post-well capping workover operations in Kuwait oil fields. In mid-January, about one kill packer was being run per day. Use is expected to increase in March when a second post-capping crew arrives. Of several thousand unconventional ideas submitted to Kuwait Oil Co. (KOC) for controlling the well fires left in the aftermath of lst year's Gulf War, only about a dozen were actually used. Inflatable kill packers, designed and manufactured by Baker Service Tools and marketed by Baker Oil Tools, were one of the ideas that proved effective. The kill packers are modifications of Baker's inflatable packers that have successfully been used in capping producers on many blowouts throughout the world, including the Piper Alpha disaster in the North Sea and the Saga blowout offshore Norway

  18. Adenosine Receptor Antagonists Effect on Plasma Enhanced Killing

    Science.gov (United States)

    Bauzá, Gustavo; Moitra, Rituparna; Remick, Daniel

    2014-01-01

    Previous studies demonstrated that naïve plasma has inherent capabilities to enhance bacterial opsonization and phagocyte killing but not all plasma is equally effective. This raised the question of whether plasma constituents other than opsonins may play a role. Adenosine receptor antagonists have been shown to modulate cytokine response and survival in mice after a bacterial challenge. We investigated whether selective adenosine receptor blockade would influence the ability of naïve plasma to effectively control bacterial growth. Colonic bacteria, and thioglycollate elicited peritoneal macrophages and neutrophils were obtained from naïve mice. Stock murine plasma from naïve was purchased and categorized as having high plasma enhanced bacterial killing capacity using our previously described methods. Bacteria and plasma were incubated in order to allow for opsonization and then added to macrophages previously exposed to selected adenosine receptor antagonists; ZM 241385: A2A, MRS1754: A2B, DPCPX: A1, and MRS1220: A3. The final mixture was plated on blood agar plates in aerobic and anaerobic conditions and bacterial colony forming units quantified after 24 hours. This study demonstrated that exogenous adenosine was able to significantly decrease phagocyte killing of cecal bacteria. Blocking adenosine receptors with selective antagonists altered the bacterial killing capacity of plasma. Selectively blocking the A1,A2A, or A2B receptors proved most beneficial at reversing the effect of adenosine. Consistent with previous work, only macrophage killing of bacteria could be modulated by adenosine receptor blockade since neutrophils were unaffected. These data demonstrate that adenosine decreases macrophage killing of enteric bacteria and that this effect is mediated through the adenosine receptors. PMID:24089004

  19. From conformal Killing vector fields to boost-rotational symmetry

    Scientific Electronic Library Online (English)

    J, Estevez-Delgado; T, Zannias.

    2007-02-01

    Full Text Available Se discute la conexión entre variedades Riemannianas (?,) de dimension tres que admiten un campo vectorial de Killing conforme ? y espacios- tiempo estáticos asociados a sistemas en el vacío o no-vacío. Cualquiera de estas variedades [...] (?,) generan un espacio-tiempo (M, g) e igual generan un espacio-tiempo (M, g,?), donde (g, ?) satisfacen las ecuaciones para el campo escalar asociadas a los sistemas de Einstein-Klein-Gordon con acoplamiento mínimo o conforme. Los espacios-tiempo asociados resultantes admiten cuatro campos vectoriales de Killing o una simetría de "boost" y rotacional. Se argumenta como esta conexión va mas allá de los sistemas en el vacío o de los sistemas de campos escalares y esto puede ser visto como un mecanismo para generar soluciones de las ecuaciones de Einstein, que admitan un campo vectorial de Killing ortogonal a una hipersuperficie. Abstract in english We discuss a connection between three-dimensional Riemannian manifolds (?,) admitting a special conformal Killing vector field ? and static vacuum or non-vacuum spacetimes. Any such (?,[...] mf/v53s2/a5s2.jpg">) generates a vacuum spacetime (M,g) but it also generates a spacetime (M, g, ?), where (g, ?) satisfies the Einstein-Klein-Gordon massless minimally coupled gravity equations, or the Einstein-Conformal scalar field equations. The resulting spacetimes either admit four Killing vector fields or possess boost and rotational symmetry. We argue that this connection goes beyond the vacuum or Einstein-scalar field system and it should be viewed as a mechanism of generating solutions for the Einstein equations, admitting a hypersurface orthogonal Killing vector field.

  20. Laboratory evaluation of Mesocyclops annulatus (Wierzejski, 1892 (Copepoda: Cyclopidea as a predator of container-breeding mosquitoes in Argentina

    Directory of Open Access Journals (Sweden)

    María V Micieli

    2002-09-01

    Full Text Available In laboratory bioassays we tested the predatory capacity of the copepod Mesocyclops annulatus on Aedes aegypti and Culex pipiens larvae. A single adult female of M. annulatus caused 51.6% and 52.3% mortality of 50 first instar larvae of Ae. aegypti and Cx. pipiens respectively, in a 72 h test period. When alternative food was added to the containers, mortality rates declined to 16% and 10.3% for Ae. aegypti and Cx. pipiens respectively. When 50 first instar larvae of each of the two mosquito species tested were placed together with a single adult female of M. annulatus, mortality rates were 75.5% for Ae. aegypti larvae and 23.5% for Cx. pipiens larvae in a three day test period. Different density of adult females of M. annulatus ranged from 5 to 25 females produced mortality rates of Ae. aegypti first instar larvae from 50% to 100% respectively. When a single adult female of M. annulatus was exposed to an increasing number of first-instar Ae. aegypti larvae ranging from 10 to 100, 100% mortality was recorded from 1 to 25 larvae, then mortality declined to 30% with 100 larvae. The average larvae killed per 24 h period by a single copepod were 29.

  1. Infection and Killing of Multiple Myeloma by Adenoviruses

    OpenAIRE

    Senac, Julien S.; Doronin, Konstantin; Russell, Stephen J.; Jelinek, Diane F.; Greipp, Philip R.; Barry, Michael A.

    2009-01-01

    Oncolytic virotherapy makes use of the natural ability of viruses to infect and kill cancer cells. Adenovirus serotype 5 (Ad5) has been approved for use in humans as a therapy for solid cancers. In this study, we have tested whether Ad5 and low-seroprevalence adenoviruses can be used as oncolytics for multiple myeloma (MM). We show that Ad5 productively infects most myeloma cell lines, replicates to various degrees, and mediates oncolytic cell killing in vitro and in vivo. Comparison of Ad5 w...

  2. The enhancement of arbovirus transmission and disease by mosquito saliva is associated with modulation of the host immune response

    OpenAIRE

    Schneider, Bradley S.; Higgs, Stephen

    2008-01-01

    Arthropod-borne viruses have emerged as a major human health concern. Viruses transmitted by mosquitoes are the cause of the most serious and widespread arbovirus diseases worldwide and are ubiquitous in both feral and urban settings. Arboviruses, including dengue and West Nile virus are injected into vertebrates within mosquito saliva during mosquito feeding. Mosquito saliva contains anti-haemostatic, anti-inflammatory and immunomodulatory molecules that facilitate the acquisition of a blood...

  3. Hemolytic C-Type Lectin CEL-III from Sea Cucumber Expressed in Transgenic Mosquitoes Impairs Malaria Parasite Development

    OpenAIRE

    Yoshida, S.; Shimada, Y; Kondoh, D; Kouzuma, Y; Ghosh, AK (Anup); Jacobs-Lorena, M.; Sinden, RE

    2007-01-01

    The midgut environment of anopheline mosquitoes plays an important role in the development of the malaria parasite. Using genetic manipulation of anopheline mosquitoes to change the environment in the mosquito midgut may inhibit development of the malaria parasite, thus blocking malaria transmission. Here we generate transgenic Anopheles stephensi mosquitoes that express the C-type lectin CEL-III from the sea cucumber, Cucumaria echinata, in a midgut-specific manner. CEL-III has strong and ra...

  4. Differential Induction of Type I Interferon Responses in Myeloid Dendritic Cells by Mosquito and Mammalian-Cell-Derived Alphaviruses?

    OpenAIRE

    Shabman, Reed S.; Morrison, Thomas E.; Moore, Christopher; White, Laura; Suthar, Mehul S.; Hueston, Linda; Rulli, Nestor; Lidbury, Brett; Ting, Jenny P. -y; Mahalingam, Suresh; Heise, Mark T.

    2006-01-01

    Dendritic cells (DCs) are an important early target cell for many mosquito-borne viruses, and in many cases mosquito-cell-derived arboviruses more efficiently infect DCs than viruses derived from mammalian cells. However, whether mosquito-cell-derived viruses differ from mammalian-cell-derived viruses in their ability to induce antiviral responses in the infected dendritic cell has not been evaluated. In this report, alphaviruses, which are mosquito-borne viruses that cause diseases ranging f...

  5. Use of geographic information systems to depict and analyze mosquito population trends.

    Science.gov (United States)

    Mosquitoes transmit (vector) disease agents that cause malaria, yellow fever, dengue, West Nile fever, and encephalitis. Spread of these diseases is controlled by the management of mosquito population levels, changes in which are monitored in vector surveillance programs by the use of mechanical tr...

  6. Native Argentinean cyclopoids (Crustacea: Copepoda) as predators of Aedes aegypti and Culex pipiens (Diptera: Culicidae) mosquitoes

    Scientific Electronic Library Online (English)

    María C, Tranchida; María V, Micieli; Arnaldo, Maciá; Juan J, García.

    1059-10-01

    Full Text Available Se hizo una prospección de copépodos en La Plata, Argentina, con los objetivos de caracterizar la comunidad local de copépodos larvívoros en sitios de cría de mosquitos, e identificar nuevas especies depredadoras de los mosquitos de contenedores artificiales Aedes aegypti y Culex pipiens. La diversi [...] dad de ciclopoides larvívoros fue máxima en charcos permanentes. Se examinó la depredación por sexos y edad, la selectividad por especies de mosquito, y la tasa de depredación diaria durante cinco días en Acanthocyclops robustus, Diacyclops uruguayensis, Macrocyclops albidus y Mesocyclops longisetus. Los copépodos hembra presentaron la capacidad depredadora más alta. No se encontró preferencia por alguna especie de mosquito. De acuerdo al potencial de depredación en general, los copépodos se ordenan así: D. uruguayensis Abstract in english Copepods from La Plata, Argentina were investigated to characterize the local community of larvivorous copepods inhabiting mosquito breeding sites and to identify new predator species of the mosquitoes which occur in artificial containers, Aedes aegypti and Culex pipiens. Diversity of larvivorous cy [...] clopoids was highest in permanent pools. Predation by sex and age, selectivity on mosquito species, and daily predation rate during five days were studied for Acanthocyclops robustus, Diacyclops uruguayensis, Macrocyclops albidus and Mesocyclops longisetus. Female copepods presented the highest predatory capacity. No predatory preference for mosquito species was found. According to overall predation potential, copepods were ranked as follows: D. uruguayensis

  7. Response of adult mosquitoes to light emitting diodes placed in resting boxes and in the field.

    Science.gov (United States)

    Resting boxes are passive devices used to attract and capture mosquitoes seeking shelter. Increasing the attractiveness of these devices could improve their effectiveness. Light emitting diodes (LEDs) can be attractive to mosquitoes when used together with other trapping devices. Therefore restin...

  8. Vector competence of Aedes aegypti mosquitoes for filarial nematodes is affected by age and nutrient limitation.

    Science.gov (United States)

    Ariani, Cristina V; Juneja, Punita; Smith, Sophia; Tinsley, Matthew C; Jiggins, Francis M

    2015-01-01

    Mosquitoes are one of the most important vectors of human disease. The ability of mosquitoes to transmit disease is dependent on the age structure of the population, as mosquitoes must survive long enough for the parasites to complete their development and infect another human. Age could have additional effects due to mortality rates and vector competence changing as mosquitoes senesce, but these are comparatively poorly understood. We have investigated these factors using the mosquito Aedes aegypti and the filarial nematode Brugia malayi. Rather than observing any effects of immune senescence, we found that older mosquitoes were more resistant, but this only occurred if they had previously been maintained on a nutrient-poor diet of fructose. Constant blood feeding reversed this decline in vector competence, meaning that the number of parasites remained relatively unchanged as mosquitoes aged. Old females that had been maintained on fructose also experienced a sharp spike in mortality after an infected blood meal ("refeeding syndrome") and few survived long enough for the parasite to develop. Again, this effect was prevented by frequent blood meals. Our results indicate that old mosquitoes may be inefficient vectors due to low vector competence and high mortality, but that frequent blood meals can prevent these effects of age. PMID:25446985

  9. Using green fluorescent malaria parasites to screen for permissive vector mosquitoes

    Science.gov (United States)

    Frischknecht, Friedrich; Martin, Beatrice; Thiery, Isabelle; Bourgouin, Catherine; Menard, Robert

    2006-01-01

    Background The Plasmodium species that infect rodents, particularly Plasmodium berghei and Plasmodium yoelii, are useful to investigate host-parasite interactions. The mosquito species that act as vectors of human plasmodia in South East Asia, Africa and South America show different susceptibilities to infection by rodent Plasmodium species. P. berghei and P. yoelii infect both Anopheles gambiae and Anopheles stephensi, which are found mainly in Africa and Asia, respectively. However, it was reported that P. yoelii can infect the South American mosquito, Anopheles albimanus, while P. berghei cannot. Methods P. berghei lines that express the green fluorescent protein were used to screen for mosquitoes that are susceptible to infection by P. berghei. Live mosquitoes were examined and screened for the presence of a fluorescent signal in the abdomen. Infected mosquitoes were then examined by time-lapse microscopy to reveal the dynamic behaviour of sporozoites in haemolymph and extracted salivary glands. Results A single fluorescent oocyst can be detected in live mosquitoes and P. berghei can infect A. albimanus. As in other mosquitoes, P. berghei sporozoites can float through the haemolymph and invade A. albimanus salivary glands and they are infectious in mice after subcutaneous injection. Conclusion Fluorescent Plasmodium parasites can be used to rapidly screen susceptible mosquitoes. These results open the way to develop a laboratory model in countries where importation of A. gambiae and A. stephensi is not allowed. PMID:16569221

  10. Don't Let the Bugs Bite: Preventing Dengue and Other Diseases Spread by Mosquitoes

    Centers for Disease Control (CDC) Podcasts

    2007-12-10

    This year (2007) CDC is receiving a great many reports of cases of Dengue fever, which is spread by mosquitoes. This podcast discusses ways travelers to the tropics can protect themselves from mosquito bites.  Created: 12/10/2007 by National Center for the Prevention, Detection and Control of Infectious Diseases (NCPDCID).   Date Released: 12/10/2007.

  11. Using green fluorescent malaria parasites to screen for permissive vector mosquitoes

    Directory of Open Access Journals (Sweden)

    Martin Beatrice

    2006-03-01

    Full Text Available Abstract Background The Plasmodium species that infect rodents, particularly Plasmodium berghei and Plasmodium yoelii, are useful to investigate host-parasite interactions. The mosquito species that act as vectors of human plasmodia in South East Asia, Africa and South America show different susceptibilities to infection by rodent Plasmodium species. P. berghei and P. yoelii infect both Anopheles gambiae and Anopheles stephensi, which are found mainly in Africa and Asia, respectively. However, it was reported that P. yoelii can infect the South American mosquito, Anopheles albimanus, while P. berghei cannot. Methods P. berghei lines that express the green fluorescent protein were used to screen for mosquitoes that are susceptible to infection by P. berghei. Live mosquitoes were examined and screened for the presence of a fluorescent signal in the abdomen. Infected mosquitoes were then examined by time-lapse microscopy to reveal the dynamic behaviour of sporozoites in haemolymph and extracted salivary glands. Results A single fluorescent oocyst can be detected in live mosquitoes and P. berghei can infect A. albimanus. As in other mosquitoes, P. berghei sporozoites can float through the haemolymph and invade A. albimanus salivary glands and they are infectious in mice after subcutaneous injection. Conclusion Fluorescent Plasmodium parasites can be used to rapidly screen susceptible mosquitoes. These results open the way to develop a laboratory model in countries where importation of A. gambiae and A. stephensi is not allowed.

  12. Cold storage of the northern house mosquito, Culex pipiens, in the absence of diapause

    Science.gov (United States)

    One major obstacle in vector biology experimentation is the rearing of mosquitoes. Most mosquito colonies require substantial effort to maintain, including a blood meal at least once a month for optimal performance. While the induction of diapause can be used to reduce the amount of work required ...

  13. Field evaluation of boric acid and fipronil based bait stations against adult mosquitoes

    Science.gov (United States)

    The effectiveness of boric acid (1%) and fipronil (0.1%) bait stations in reducing the number of laboratory-reared female Aedes aegypti and Ochlerotatus taeniorhynchus mosquitoes released in outdoor screened cages was evaluated. Both toxicants reduced landing rates of the two mosquito species on a ...

  14. Insectos acuáticos biorreguladores de larvas de mosquito presentes en los "Pantanos de Villa", Lima, Perú

    Directory of Open Access Journals (Sweden)

    ISRAEL GARCÍA ÁVILA

    1996-12-01

    Full Text Available Se colectaron y determinaron los principales insectos acuáticos biorreguladores de larvas de mosquito presentes en distintos reservorios en los "Pantanos de Villa", Lima, Perú, donde encontramos larvas y pupas de mosquito de las especies Culex quinquefasciatus Say y Aedes scapularis Rondani, en acuatorios donde no observamos insectos acuáticos. En aquéllos donde estaban presentes estos efectivos biorreguladores de larvas de mosquito como fueron Ischnura ramburri (Selys, Ceratura capreola (Hagen, Erithrodiplax cleopatra Ris, Aeschna elsia Calvert, Tropisternus dorsalis Brullé, Thermonectes circunscripta Latr, Belostoma asiaticum (Mayr y Buenoa absidata Truxal, no encontramos larvas de mosquito. Se muestran las especies de insectos acuáticos colectados y las variables físico-químicas del agua en los reservorios investigados.The main aquatic insects bioregulators of mosquitoe larvae living in different reservoirs at the "Pantanos de Villa", Lima, Perú, were collected and determined. Mosquitoe larvae and pupas of the Culex quinquefasciatus Say and Aedes scapularis Rondani species were found in water reservoirs where aquatic insects are not observed. In those where there were these effective bioregulators of mosquitoe larvae such as Ischnura ramburii (Selys, Ceratura capreola (Hagen, Erithrodoplax cleopatra Ris, Aschna elsia Calvert, Tropisternus dorsalis Brullé, Thermonectes circunscripta Lart, Belostoma asiaticum (Mayr, and Buenos absidata Truxal, no mosquitoe larvae were found. The species of the aquatic insects collected in the reservoirs as well as the physical and chemical variables of the water are shown.

  15. Insectos acuáticos biorreguladores de larvas de mosquito presentes en los "Pantanos de Villa", Lima, Perú

    Scientific Electronic Library Online (English)

    ISRAEL, GARCÍA ÁVILA; RONALD, VIVAR GUZMÁN; JAIME, QUEZADA MÁRQUEZ; PEDRO, HUAMÁN MAYTA.

    1996-12-01

    Full Text Available Se colectaron y determinaron los principales insectos acuáticos biorreguladores de larvas de mosquito presentes en distintos reservorios en los "Pantanos de Villa", Lima, Perú, donde encontramos larvas y pupas de mosquito de las especies Culex quinquefasciatus Say y Aedes scapularis Rondani, en acua [...] torios donde no observamos insectos acuáticos. En aquéllos donde estaban presentes estos efectivos biorreguladores de larvas de mosquito como fueron Ischnura ramburri (Selys), Ceratura capreola (Hagen), Erithrodiplax cleopatra Ris, Aeschna elsia Calvert, Tropisternus dorsalis Brullé, Thermonectes circunscripta Latr, Belostoma asiaticum (Mayr) y Buenoa absidata Truxal, no encontramos larvas de mosquito. Se muestran las especies de insectos acuáticos colectados y las variables físico-químicas del agua en los reservorios investigados. Abstract in english The main aquatic insects bioregulators of mosquitoe larvae living in different reservoirs at the "Pantanos de Villa", Lima, Perú, were collected and determined. Mosquitoe larvae and pupas of the Culex quinquefasciatus Say and Aedes scapularis Rondani species were found in water reservoirs where aqua [...] tic insects are not observed. In those where there were these effective bioregulators of mosquitoe larvae such as Ischnura ramburii (Selys), Ceratura capreola (Hagen), Erithrodoplax cleopatra Ris, Aschna elsia Calvert, Tropisternus dorsalis Brullé, Thermonectes circunscripta Lart, Belostoma asiaticum (Mayr), and Buenos absidata Truxal, no mosquitoe larvae were found. The species of the aquatic insects collected in the reservoirs as well as the physical and chemical variables of the water are shown.

  16. Using a Near-Infrared Spectrometer to Estimate the Age of Anopheles Mosquitoes Exposed to Pyrethroids

    OpenAIRE

    Sikulu, Maggy T.; Majambere, Silas; Khatib, Bakar O; Ali, Abdullah S.; Hugo, Leon E.; Dowell, Floyd E

    2014-01-01

    We report on the accuracy of using near-infrared spectroscopy (NIRS) to predict the age of Anopheles mosquitoes reared from wild larvae and a mixed age-wild adult population collected from pit traps after exposure to pyrethroids. The mosquitoes reared from wild larvae were estimated as

  17. Blood Meal Analysis of Mosquitoes Involved in a Rift Valley fever Outbreak

    Science.gov (United States)

    Background: Rift Valley fever (RVF) is a zoonosis of domestic ruminants in Africa. Bloodfed mosquitoes collected during the 2006-2007 RVF outbreak in Kenya were analyzed to determine the virus infection status and animal source of the bloodmeals. Bloodmeals from individual mosquito abdomens were sc...

  18. Culex torrentium Mosquito Role as Major Enzootic Vector Defined by Rate of Sindbis Virus Infection, Sweden, 2009

    Science.gov (United States)

    Verner-Carlsson, Jenny; Larsson, Anders; Ahmed, Raija; Lundkvist, Åke; Lundström, Jan O.

    2015-01-01

    We isolated Sindbis virus (SINV) from the enzootic mosquito vectors Culex torrentium, Cx. pipiens, and Culiseta morsitans collected in an area of Sweden where SINV disease is endemic. The infection rate in Cx. torrentium mosquitoes was exceptionally high (36 infections/1,000 mosquitoes), defining Cx. torrentium as the main enzootic vector of SINV in Scandinavia. PMID:25898013

  19. Swarming mechanisms in the yellow fever mosquito: aggregation pheromones involved in the mating behavior of Aedes aegypti

    Science.gov (United States)

    Mosquitoes of various species mate in swarms comprised of tens to thousands flying males. Yet little information is known about mosquito swarming mechanism. Discovering chemical cues involved in mosquito biology leads to better adaptation of disease control interventions. In this study, we aimed ...

  20. BOOK CHAPTER: BIOMETRICS AND BEHAVIOR IN MOSQUITO REPELLENT ASSAY. FOR: INSECT REPELLENTS: PRINCIPLES, METHODS, AND USE. CRC PRESS, BOCA RATON.

    Science.gov (United States)

    The discovery and evaluation of mosquito repellents is made using a process called biological assay (bioassay). The identification of mosquito repellent activity in bioassays is complicated because many types of bioassay systems are used and because the methods for rearing and manipulating mosquito...

  1. Preliminary evaluation of mosquito larvicidal efficacy of plant extracts

    Directory of Open Access Journals (Sweden)

    N.G. Das, D. Goswami & B. Rabha

    2007-06-01

    Full Text Available Mosquitoes are the most important single group ofinsects in terms of public health importance, whichtransmit a number of diseases, such as malaria, filariasis,dengue, Japanese encephalitis, etc. causing millionsof deaths every year. Repeated use of syntheticinsecticides for mosquito control has disrupted naturalbiological control systems and led to resurgencesin mosquito populations. It has also resulted in thedevelopment of resistance1, undesirable effects onnon-target organisms and fostered environmental andhuman health concern2, which initiated a search foralternative control measures. Plants are considered asa rich source of bioactive chemicals3 and they may bean alternative source of mosquito control agents.Natural products of plant origin with insecticidalproperties have been tried in the recent past for controlof variety of insect pests and vectors. Essentialoils of leaf and bark of Cryptomeria japonica demonstratedhigh larvicidal activity against Aedesaegypti (Diptera: Culicidae larvae4. Insecticidalactivity of plant essential oils has been well-describedby Isman5. Azadiractin, the active ingredient of neemhas long been recognised for its mosquito larvicidalcapability. The extracts of Murraya koenigii, Coriandrumsativam, Ferula asafetida and Trigonella foenumgraceum were found to be effective and showedencouraging results against Ae. aegypti6 and Culex(Diptera: Culicidae mosquito larvae7. It is also reportedthat many compounds with insecticidal potentialhave been isolated from the genus Piper—Pipercide,isolated from Piper negrum (black piper hasbeen found to be just as active against adjuki beanweevils as the pyrethroides8. Phytochemicals derivedfrom plant sources can act as larvicide, insect growthregulators, repellent and ovipositor attractant andhave different activities observed by many researchers9–11. However, insecticides of plant origin havebeen extensively used on agricultural pests and to avery limited extent, against insect vectors of publichealth importance.Northeastern region of India is considered as a majorbiodiversity hot spot. The eastern Himalayas range,which extends all through the northern border ofAssam, is a rich treasure house of many promisingmedicinal and aromatic plants. In the present communication,an attempt has been made to evaluate themosquito larvicidal efficacy of methanol and ethanolextracts of different parts of five indigenous plantsagainst Ae. albopictus (Diptera: Culicidae and Culexquinquefasciatus larvae in laboratory conditions.Plant materials were collected from the foothill forestsof Sonitpur district, Assam bordering ArunachalPradesh during April and May 2005. They were segregatedas leaf, stem, bark, root and fruit/pericarp andair-dried in a shady place. Dried materials wereground in a table model grinder. The ground plant materialswere dipped in solvents (methanol and ethanolShort Research Communications146 J VECT BORNE DIS 44, JUNE 2007in tightly capped jars separately for 48 h. The solventsalong with extracts were drained out, filtered andsemisolid extracts were obtained in vacuum usingrotary evaporator. The semisolid extracts were lyophilisedto obtain solid extracts. Stock solutions of desiredconcentration were prepared in distilled waterusing 1 ppm teepol as emulsifying agent and subsequentdilutions were made as per requirement. Larvicidalbioassay was carried out as per standard WHOtechniques in 500 ml glass beakers containing 250 mlof water and 25 numbers of late III or early IV instarmosquito larvae for various concentrations. Threedifferent concentrations of each extract were tried outat a time with six replicates. One control was kept witheach set of experiment and mortality was recordedafter 24 h. Five sets of experiments were conductedfor each extract. Tests were carried out under controlledlaboratory conditions (temperature 27 ± 2oCagainst laboratory reared Ae. albopictus and Cx. quinquefasciatus(Diptera: Culicidae larvae. Values obtainedwere subjected to log probit regression analysisto obtain LC50 and LC90 values with 95% confidencel

  2. Large-scale control of mosquito vectors of disease

    International Nuclear Information System (INIS)

    By far the most important vector borne disease is malaria transmitted by Anopheles mosquitoes causing an estimated 300-500 million clinical cases per year and 1.4-2.6 million deaths, mostly in tropical Africa (WHO 1995). The second most important mosquito borne disease is lymphatic filariasis, but there are now such effective, convenient and cheap drugs for its treatment that vector control will now have at most a supplementary role (Maxwell et al. 1999a). The only other mosquito borne disease likely to justify large-scale vector control is dengue which is carried in urban areas of Southeast Asia and Latin America by Aedes aegypti L. which was also the urban vector of yellow fever in Latin America. This mosquito was eradicated from most countries of Latin America between the 1930s and 60s but, unfortunately in recent years, it has been allowed to re-infest and cause serious dengue epidemics, except in Cuba where it has been held close to eradication (Reiter and Gubler 1997). In the 1930s and 40s, invasions by An. gambiae Giles s.l., the main tropical African malaria vector, were eradicated from Brazil (Soper and Wilson 1943) and Egypt (Shousha 1947). It is surprising that greatly increased air traffic has not led to more such invasions of apparently climatically suitable areas, e.g., of Polynesia which has no anophelines and therefore no malaria. The above mentioned temporary or permanent eradications were achieved before the advent of DDT, using larvicidal methods (oadvent of DDT, using larvicidal methods (of a kind which would now be considered environmentally unacceptable) carried out by rigorously disciplined teams. MALARIA Between the end of the Second World War and the 1960s, the availability of DDT for spraying of houses allowed eradication of malaria from the Soviet Union, southern Europe, the USA, northern Venezuela and Guyana, Taiwan and the Caribbean Islands, apart from Hispaniola. Its range and intensity were also greatly reduced in China, India and South Africa and, at least temporarily, in Sri Lanka. In several Latin American countries much progress was made, but this has been reversed following the abandonment of DDT without any replacement being brought into use (Roberts et al. 1997). After eradication from the Soviet Union in the 1960s, malaria epidemics are now returning to Azerbaijan and Tadjikistan following the collapse of the health system and the descent into civil war (Nikolaeva 1996). In a few instances, unlooked-for eradication has been claimed to have occurred locally as a result of DDT house spraying of species which are strongly endophilic, i.e., with a strong tendency to rest in houses. There was much enthusiasm for SIT for mosquitoes in the 1960s and early 70s but it went into eclipse, largely for political reasons (Anonymous 1975). In the 70s, it was shown in various species of mosquito that chemically sterilised males, or males carrying translocations and a meiotic drive factor or cytoplasmically incompatible with the local population, could compete reasonably well for mates as shown by induction of sterility in the eggs laid by wild females (Lofgren et al. 1974, Grover et al. 1976a, b)

  3. Potency of Pandanus amaryllifolius and Notophanax scutellarium as Aedes albopictus Mosquito Repellent

    Directory of Open Access Journals (Sweden)

    Rina Marina

    2012-12-01

    Full Text Available Aedes aegypti and Ae. albopictus mosquitoes being the vector of Dengue Haemorrhagic Fever (DHF. Various effort have been done to control the mosquitoes, including using plant extract as repellent. Pandanus amaryllifolius and Notophanax scutellarium leaf were known to posses repellent activity for mosquito species. The study aimed to examine efJectiveness of P. amaryllifolius and N. scutellarium leaves as repellent for Ae. albopictus. The result study on 1 hr treatment showed that power protection of pandan leaves (N. scutellarium was 93.55%, while mangkokan leaves (P. amaryllifolius was 87.5%. Based on ANOVA analysis, there was not significantly different of power protection between N. scutellarium leaves and P. amaryllifolius leaves extracts against Ae. albopictus mosquitoes. Both of these test, plants has showed the potential to be a repellent and eliminate the emergence of Ae. albopictus mosquitoes, so it may effectively reduce contact between host and dengue vector.

  4. Human-to-mosquito transmission efficiency increases as malaria is controlled.

    Science.gov (United States)

    Churcher, Thomas S; Trape, Jean-François; Cohuet, Anna

    2015-01-01

    The efficiency of malaria transmission between human and mosquito has been shown to be influenced by many factors in the laboratory, although their impact in the field and how this changes with disease endemicity are unknown. Here we estimate how human-mosquito transmission changed as malaria was controlled in Dielmo, Senegal. Mathematical models were fit to data collected between 1990 and the start of vector control in 2008. Results show that asexual parasite slide prevalence in humans has reduced from 70 to 20%, but that the proportion of infectious mosquitoes has remained roughly constant. Evidence suggests that this is due to an increase in transmission efficiency caused by a rise in gametocyte densities, although the uneven distribution of mosquito bites between hosts could also contribute. The resilience of mosquito infection to changes in endemicity will have important implications for planning disease control, and the development and deployment of transmission-reducing interventions. PMID:25597498

  5. Mosquito surveillance and polymerase chain reaction detection of West Nile virus, New York State.

    Science.gov (United States)

    White, D J; Kramer, L D; Backenson, P B; Lukacik, G; Johnson, G; Oliver, J A; Howard, J J; Means, R G; Eidson, M; Gotham, I; Kulasekera, V; Campbell, S

    2001-01-01

    West Nile (WN) virus was detected in the metropolitan New York City (NYC) area during the summer and fall of 1999. Sixty-two human cases, 7 fatal, were documented. The New York State Department of Health initiated a departmental effort to implement a statewide mosquito and virus surveillance system. During the 2000 arbovirus surveillance season, we collected 317,676 mosquitoes, submitted 9,952 pools for virus testing, and detected 363 WN virus-positive pools by polymerase chain reaction (PCR). Eight species of mosquitoes were found infected. Our mosquito surveillance system complemented other surveillance systems in the state to identify relative risk for human exposure to WN virus. PCR WN virus-positive mosquitoes were detected in NYC and six counties in the lower Hudson River Valley and metropolitan NYC area. Collective surveillance activities suggest that WN virus can disperse throughout the state and may impact local health jurisdictions in the state in future years. PMID:11585526

  6. Detection of Porcine Circovirus Type 2 (PCV2 in Mosquitoes from Pig Farms by PCR

    Directory of Open Access Journals (Sweden)

    Xiaohong Yang, Lidan Hou, Jing Ye, Qigai He and Shengbo Cao*

    2012-01-01

    Full Text Available To investigate, whether mosquitoes could be potential vectors that maintain or transmit PCV2, 59 mosquito samples were collected from suspicious PCV2-infected pig farms in Hubei and Anhui province, China. Total DNA from these mosquitoes was extracted and then tested for presence of PCV2 nucleic acid by PCR. Four (6.78% samples showed the positive result. Subsequently, the positive PCR product was cloned into pEASY-T1 vector and sequenced. Sequence analysis displayed that homology between the PCR products and PCV2 strains were more than 94%. These results demonstrate that PCV2 nucleic acid exists in these mosquitoes, which suggests that mosquitoes could serve as mechanical transmission vectors of PCV2.

  7. Transfer of toxin genes to alternate bacterial hosts for mosquito control

    Scientific Electronic Library Online (English)

    Sergio, Orduz; Nora, Restrepo; Maria M, Patiño; William, Rojas.

    1995-02-01

    Full Text Available Mosquitoes are vector of serious human and animal diseases, such as malaria, dengue, yellow fever, among others. The use of biological control agents has provide an environmentally safe and highly specific alternative to the use of chemical insecticides in the control of vector borne diseases. Bacil [...] lus thuringiensis and B. sphaericus produce toxic proteins to mosquito larvae. Great progress has been made on the biochemical and molecular characterization of such proteins and the genes encoding them. Nevertheless, the low residuality of these biological insecticides is one of the major drawbacks. This article present some interesting aspects of the mosquito larvae feeding habits and review the attempts that have been made to genetically engineer microorganisms that while are used by mosquito larvae as a food source should express the Bacillus toxin genes in order to improve the residuality and stability in the mosquito breeding ponds.

  8. A mosquito lipoxin/lipocalin complex mediates innate immune priming in Anopheles gambiae.

    Science.gov (United States)

    Ramirez, Jose Luis; de Almeida Oliveira, Giselle; Calvo, Eric; Dalli, Jesmond; Colas, Romain A; Serhan, Charles N; Ribeiro, Jose M; Barillas-Mury, Carolina

    2015-01-01

    Exposure of Anopheles gambiae mosquitoes to Plasmodium infection enhances the ability of their immune system to respond to subsequent infections. However, the molecular mechanism that allows the insect innate immune system to 'remember' a previous encounter with a pathogen has not been established. Challenged mosquitoes constitutively release a soluble haemocyte differentiation factor into their haemolymph that, when transferred into Naive mosquitoes, also induces priming. Here we show that this factor consists of a Lipoxin/Lipocalin complex. We demonstrate that innate immune priming in mosquitoes involves a persistent increase in expression of Evokin (a lipid carrier of the lipocalin family), and in their ability to convert arachidonic acid to lipoxins, predominantly Lipoxin A4. Plasmodium ookinete midgut invasion triggers immune priming by inducing the release of a mosquito lipoxin/lipocalin complex. PMID:26100162

  9. Distribution of mosquito larvae in various breeding sites in National Zoo Malaysia.

    Science.gov (United States)

    Muhammad-Aidil, R; Imelda, A; Jeffery, J; Ngui, R; Wan Yusoff, W S; Aziz, S; Lim, Y A L; Rohela, M

    2015-03-01

    Mosquitoes are principal vectors of major vector-borne diseases. They are widely found throughout urban and rural areas in Malaysia. They are responsible for various vector-borne diseases such as dengue, malaria, filariasis and encephalitis. A total of 158 mosquito larvae specimens were collected from the National Zoo, Malaysia, from 11 types of breeding habitats during the study period from end of May 2007 to July 2007. Aedes albopictus was the predominant species (35.4%), followed by Tripteroides aranoides (26.6%), Lutzia halifaxii (11.4%), Aedes alboscutellatus (10.1%), Aedes caecus (8.9%), Armigeres spp. (4.4%), Malaya genurostris (2.5%) and Culex vishnui (0.6%). It is important to have a mosquito free environment in a public place like the zoo. Routine larval surveillance should be implemented for an effective mosquito control program in order to reduce mosquito population. PMID:25801269

  10. Transfer of toxin genes to alternate bacterial hosts for mosquito control

    Directory of Open Access Journals (Sweden)

    Sergio Orduz

    1995-02-01

    Full Text Available Mosquitoes are vector of serious human and animal diseases, such as malaria, dengue, yellow fever, among others. The use of biological control agents has provide an environmentally safe and highly specific alternative to the use of chemical insecticides in the control of vector borne diseases. Bacillus thuringiensis and B. sphaericus produce toxic proteins to mosquito larvae. Great progress has been made on the biochemical and molecular characterization of such proteins and the genes encoding them. Nevertheless, the low residuality of these biological insecticides is one of the major drawbacks. This article present some interesting aspects of the mosquito larvae feeding habits and review the attempts that have been made to genetically engineer microorganisms that while are used by mosquito larvae as a food source should express the Bacillus toxin genes in order to improve the residuality and stability in the mosquito breeding ponds.

  11. Novel Acetylcholinesterase Target Site for Malaria Mosquito Control

    OpenAIRE

    Pang, Yuan-Ping

    2006-01-01

    Current anticholinesterase pesticides were developed during World War II and are toxic to mammals because they target a catalytic serine residue of acetylcholinesterases (AChEs) in insects and in mammals. A sequence analysis of AChEs from 73 species and a three-dimensional model of a malaria-carrying mosquito (Anopheles gambiae) AChE (AgAChE) reported here show that C286 and R339 of AgAChE are conserved at the opening of the active site of AChEs in 17 invertebrate and four insect species, res...

  12. THE MOSQUITOES OF QUINTANA ROO STATE, MEXICO (DIPTERA: CULICIDAE

    Directory of Open Access Journals (Sweden)

    Aldo I. Ortega Morales

    2010-01-01

    Full Text Available Un estudio de la distribución de los mosquitos del estado de Quintana Roo, México fue realizado por medio de colectas de estados inmaduros y adultos durante Septiembre y Octubre del 2006. Las colectas fueron realizadas en diferentes localidades de las tres provincias fisiográficas del estado: Carso Yucateco, Carso, Lomeríos de Campeche y Costa Baja de Quintana Roo. Un total de 420 larvas, 294 pupas y 726 adultos fueron colectados representando 13 géneros y 41 especies. Dos géneros, tres subgéneros y 11 especies son nuevos registros estatales para Quintana Roo.

  13. Deforestation, Mosquitoes, and Ancient Rome: Lessons for Today

    Science.gov (United States)

    Lara O'Sullivan (University of Western Australia; )

    2008-09-01

    This article highlights the complex interactions between anthropogenic ecological change and mosquito-borne disease patterns. Ancient Rome provides a historical case study of the possible interplay between deforestation and an increasing malarial disease burden, and examples drawn from across the globe suggest that the experience of Rome is being repeated today. The evidence calls for careful management of agricultural clearing and for a multidisciplinary perspective in policy development on the issue, particularly in regions where there are already indications of escalating disease rates.

  14. A note on simple applications of the Killing spinor identities

    OpenAIRE

    Bellorín Romero, Jorge Alejandro; Ortín Miguel, Tomás

    2005-01-01

    We show how the Killing Spinor Identities (KSI) can be used to reduce the number of independent equations of motion that need to be checked explicitly to make sure that a supersymmetric configuration is a classical supergravity solution. We also show how the KSI can be used to compute BPS relations between masses and charges.

  15. Illegal killing for ivory drives global decline in African elephants.

    Science.gov (United States)

    Wittemyer, George; Northrup, Joseph M; Blanc, Julian; Douglas-Hamilton, Iain; Omondi, Patrick; Burnham, Kenneth P

    2014-09-01

    Illegal wildlife trade has reached alarming levels globally, extirpating populations of commercially valuable species. As a driver of biodiversity loss, quantifying illegal harvest is essential for conservation and sociopolitical affairs but notoriously difficult. Here we combine field-based carcass monitoring with fine-scale demographic data from an intensively studied wild African elephant population in Samburu, Kenya, to partition mortality into natural and illegal causes. We then expand our analytical framework to model illegal killing rates and population trends of elephants at regional and continental scales using carcass data collected by a Convention on International Trade in Endangered Species program. At the intensively monitored site, illegal killing increased markedly after 2008 and was correlated strongly with the local black market ivory price and increased seizures of ivory destined for China. More broadly, results from application to continental data indicated illegal killing levels were unsustainable for the species between 2010 and 2012, peaking to ? 8% in 2011 which extrapolates to ? 40,000 elephants illegally killed and a probable species reduction of ? 3% that year. Preliminary data from 2013 indicate overharvesting continued. In contrast to the rest of Africa, our analysis corroborates that Central African forest elephants experienced decline throughout the last decade. These results provide the most comprehensive assessment of illegal ivory harvest to date and confirm that current ivory consumption is not sustainable. Further, our approach provides a powerful basis to determine cryptic mortality and gain understanding of the demography of at-risk species. PMID:25136107

  16. Fish Kill in the Philippines—Déjà Vu

    OpenAIRE

    Gil Jacinto

    2011-01-01

    Almost ten years ago today, the country woke up toscreaming headlines— “Massive Fish Kill inPangasinan” or something akin to that. The fish killphenomenon, familiar to fishers in freshwater andcoastal bodies of water where fish farming was beingpursued, was suddenly manifested at a scale that hadheretofore not been experienced.

  17. Fish Kill in the Philippines—Déjà Vu

    Directory of Open Access Journals (Sweden)

    Gil Jacinto

    2011-12-01

    Full Text Available Almost ten years ago today, the country woke up toscreaming headlines— “Massive Fish Kill inPangasinan” or something akin to that. The fish killphenomenon, familiar to fishers in freshwater andcoastal bodies of water where fish farming was beingpursued, was suddenly manifested at a scale that hadheretofore not been experienced.

  18. Distorted Killing Horizons and Algebraic Classification of Curvature Tensors.

    Czech Academy of Sciences Publication Activity Database

    Pravda, Vojt?ch; Zaslavskii, O.B.

    Singapore : World Scientific, 2008 - (Kleinert, H.; Jantzen, R.; Ruffini, R.), s. 2231-2233 ISBN 978-981-283-426-3. [Marcel Grossmann Meeting on General Relativity /11./. Berlín (DE), 23.07.2006-29.07.2006] Institutional research plan: CEZ:AV0Z10190503 Keywords : curvature tensor * Petrov classification * Killing horizon Subject RIV: BA - General Mathematics

  19. Ricci-flat spacetimes admitting higher rank Killing tensors

    Science.gov (United States)

    Cariglia, Marco; Galajinsky, Anton

    2015-05-01

    Ricci-flat spacetimes of signature (2 , q) with q = 2 , 3 , 4 are constructed which admit irreducible Killing tensors of rank-3 or rank-4. The construction relies upon the Eisenhart lift applied to Drach's two-dimensional integrable systems which is followed by the oxidation with respect to free parameters. In four dimensions, some of our solutions are anti-self-dual.

  20. Higher Mosquito Production in Low-Income Neighborhoods of Baltimore and Washington, DC: Understanding Ecological Drivers and Mosquito-Borne Disease Risk in Temperate Cities

    Directory of Open Access Journals (Sweden)

    Danielle Bodner

    2013-04-01

    Full Text Available Mosquito-vectored pathogens are responsible for devastating human diseases and are (reemerging in many urban environments. Effective mosquito control in urban landscapes relies on improved understanding of the complex interactions between the ecological and social factors that define where mosquito populations can grow. We compared the density of mosquito habitat and pupae production across economically varying neighborhoods in two temperate U.S. cities (Baltimore, MD and Washington, DC. Seven species of mosquito larvae were recorded. The invasive Aedes albopictus was the only species found in all neighborhoods. Culex pipiens, a primary vector of West Nile virus (WNV, was most abundant in Baltimore, which also had more tire habitats. Both Culex and Aedes pupae were more likely to be sampled in neighborhoods categorized as being below median income level in each city and Aedes pupae density was also greater in container habitats found in these lower income neighborhoods. We infer that lower income residents may experience greater exposure to potential disease vectors and Baltimore residents specifically, were at greater risk of exposure to the predominant WNV vector. However, we also found that resident-reported mosquito nuisance was not correlated with our measured risk index, indicating a potentially important mismatch between motivation needed to engage participation in control efforts and the relative importance of control among neighborhoods.

  1. Evaluation of Electronic Mosquito-Repelling Devices Using Aedes albopictus (Skuse) (Diptera: Culicidae) / Avaliação de Aparelhos Eletrônicos Repelentes de Mosquitos Usando-se Aedes albopictus (Skuse) (Diptera: Culicidae)

    Scientific Electronic Library Online (English)

    CARLOS F.S., ANDRADE; VIRGÍNIA S., BUENO.

    2001-09-01

    Full Text Available Os aparelhos repelentes de mosquitos Anti-Pic®, Mosquito Repeller® DX-600 e Bye-Bye Mosquito® foram avaliados em caixas de experimentação expondo-se a mão humana a adultos de Aedes albopictus (Skuse). Foram realizados dois conjuntos de experimentos baseados em exposições por 15 min. No primeiro, amb [...] as mãos foram introduzidas na caixa, estando uma delas com o aparelho ligado. No segundo foi introduzida uma mão de cada vez, segurando o aparelho, ligado ou não. Os aparelhos falharam em mostrar eficiência em ambas as avaliações. Uma aparente proteção de 30,3% pelo Anti-Pic® no primeiro conjunto de experimentos não foi confirmada no conjunto seguinte. Discute-se o valor desse recurso na prevenção da dengue. Abstract in english The mosquito-repelling devices Anti-Pic®, Mosquito Repeller® DX-600 and Bye-Bye Mosquito® were evaluated in boxes for experimentation by exposing human hands to Aedes albopictus (Skuse) adults. Two sets of tests were performed based on 15 min. expositions. In the first set both hands were introduced [...] in the box, one of them holding the device on. In the second set only one hand was introduced each time, holdind the device on or off. The devices failed to show efficiency in both evaluations. A seemingly 30.3% repellency due to Anti-Pic® in the first set of experiments was not confirmed in the second set. It was discussed the value of such devices for dengue prevention.

  2. Screening of Bacillus thuringiensis strains effective against mosquitoes / Prospecção de estirpes de Bacillus thuringiensis efetivas contra mosquitos

    Scientific Electronic Library Online (English)

    Rose Gomes, Monnerat; Daniel Gerhein Souza, Dias; Silvania Ferreira da, Silva; Erica Soares, Martins; Colin, Berry; Rosana, Falcão; Ana Cristina Menezes Mendes, Gomes; Lilian Botelho, Praça; Carlos Marcelo Silveira, Soares.

    2005-02-01

    Full Text Available Neste trabalho foram realizados testes de patogenicidade com 210 estirpes de Bacillus thuringiensis contra larvas de Aedes aegypti e Culex quinquefasciatus, a fim de se determinar as mais eficazes. Estas estirpes foram isoladas de diversas regiões do Brasil e estão armazenadas na coleção de Bacillus [...] spp. da Embrapa Recursos Genéticos e Biotecnologia. As estirpes selecionadas foram caracterizadas por métodos morfológicos (microscopia), bioquímicos (SDS-PAGE 10%) e moleculares (Reação em Cadeia da Polimerase). Foram selecionadas seis estirpes entomopatogênicas de Bacillus thuringiensis. Nenhuma das estirpes de Bacillus thuringiensis apresentou produtos de PCR esperados para a detecção dos genes cry4, cry11 e cyt1A. A patogenicidade das estirpes não está associada à presença das toxinas Cry4, Cry11 ou Cyt, assim, essas estirpes poderão ser utilizadas para a formatação de um bioinseticida alternativo contra mosquitos. Abstract in english The objective of this work was to evaluate 210 Bacillus thuringiensis strains against Aedes aegypti and Culex quinquefasciatus larvae to select the most effective. These strains were isolated from different regions of Brazil and are stored in a Bacillus spp. collection at Embrapa Recursos Genéticos [...] e Biotecnologia, Brasília, Brazil. The selected strains were characterized by morphological (microscopy), biochemical (SDS-PAGE 10%) and molecular (PCR) methods. Six B. thuringiensis strains were identified as mosquito-toxic after the selective bioassays. None of the strains produced the expected PCR products for detection of cry4, cry11 and cyt1A genes. These results indicate that the activity of mosquitocidal Brazilian strains are not related with Cry4, Cry11 or Cyt proteins, so they could be used as an alternative bioinsecticide against mosquitoes.

  3. Screening of Bacillus thuringiensis strains effective against mosquitoes Prospecção de estirpes de Bacillus thuringiensis efetivas contra mosquitos

    Directory of Open Access Journals (Sweden)

    Rose Gomes Monnerat

    2005-02-01

    Full Text Available The objective of this work was to evaluate 210 Bacillus thuringiensis strains against Aedes aegypti and Culex quinquefasciatus larvae to select the most effective. These strains were isolated from different regions of Brazil and are stored in a Bacillus spp. collection at Embrapa Recursos Genéticos e Biotecnologia, Brasília, Brazil. The selected strains were characterized by morphological (microscopy, biochemical (SDS-PAGE 10% and molecular (PCR methods. Six B. thuringiensis strains were identified as mosquito-toxic after the selective bioassays. None of the strains produced the expected PCR products for detection of cry4, cry11 and cyt1A genes. These results indicate that the activity of mosquitocidal Brazilian strains are not related with Cry4, Cry11 or Cyt proteins, so they could be used as an alternative bioinsecticide against mosquitoes.Neste trabalho foram realizados testes de patogenicidade com 210 estirpes de Bacillus thuringiensis contra larvas de Aedes aegypti e Culex quinquefasciatus, a fim de se determinar as mais eficazes. Estas estirpes foram isoladas de diversas regiões do Brasil e estão armazenadas na coleção de Bacillus spp. da Embrapa Recursos Genéticos e Biotecnologia. As estirpes selecionadas foram caracterizadas por métodos morfológicos (microscopia, bioquímicos (SDS-PAGE 10% e moleculares (Reação em Cadeia da Polimerase. Foram selecionadas seis estirpes entomopatogênicas de Bacillus thuringiensis. Nenhuma das estirpes de Bacillus thuringiensis apresentou produtos de PCR esperados para a detecção dos genes cry4, cry11 e cyt1A. A patogenicidade das estirpes não está associada à presença das toxinas Cry4, Cry11 ou Cyt, assim, essas estirpes poderão ser utilizadas para a formatação de um bioinseticida alternativo contra mosquitos.

  4. Effect of Wolbachia on Replication of West Nile Virus in a Mosquito Cell Line and Adult Mosquitoes

    OpenAIRE

    Mazhar HUSSAIN; Lu, Guangjin; Torres, Shessy; Edmonds, Judith H.; Kay, Brian H.; Alexander A. Khromykh; Asgari, Sassan

    2013-01-01

    Wolbachia as an endosymbiont is widespread in insects and other arthropods and is best known for reproductive manipulations of the host. Recently, it has been shown that wMelpop and wMel strains of Wolbachia inhibit the replication of several RNA viruses, including dengue virus, and other vector-borne pathogens (e.g., Plasmodium and filarial nematodes) in mosquitoes, providing an alternative approach to limit the transmission of vector-borne pathogens. In this study, we tested the effect of W...

  5. EFFICACY OF AGERATUM CONYZOIDES AGAINST THE CONTROL OF MOSQUITOES

    Directory of Open Access Journals (Sweden)

    Neetu Arya et al.

    2011-12-01

    Full Text Available Mosquitoes transmit serious human diseases causing millions of deaths every year. Phytochemistry has proven that there are potential mosquito control agents and also alternatives to synthetic insecticides. The present paper reports Ageratum conyzoides commonly known as Kubhi in Hindi of family Astereacae. The plant after proper identification was collected shade dried and powdered to the fine mesh size. 5 different concentrations were used against IInd and IVth instar of Anapheles stephensi. Larvicidal and growth inhibitory activity of Ageratum conyzoides exhibited in the II and IVth instar larvae of the Anapheles stephensi. After 24 hours, LC50 value was determined using probit analysis method. It was notice that the LC50 value for IInd and IVth instar larvae were 238.65 and 228.54 ppm respectively. The result indicate that fourth instar larvae are more susceptible then second instar larvae .the result obtained suggest that bioactive compound of Ageratum conyzoides could be used in the search for new larvicidal compound of plant origin.

  6. Relative efficacy of various oils in repelling mosquitoes.

    Science.gov (United States)

    Ansari, M A; Razdan, R K

    1995-09-01

    Field studies were carried out to determine the relative efficacy of repellant action of vegetable, essential and chemical base oils against vector mosquitoes. Results revealed that essential oils viz. Cymbopogan martinii martinii var. Sofia (palmarosa), Cymbopogan citratus (lemon grass) and Cymbopogan nardus (citronella) oils are as effective as chemical base oil namely mylol. These oils provide almost complete protection against Anopheles culicifacies and other anopheline species. Per cent protection against Culex quinquefasciatus ranged between 95-96%. Camphor (C. camphora) oil also showed repellent action and provided 97.6% protection against An. culicifacies and 80.7% against Cx. quinquefasciatus. Vegetable oils namely mustard (B. compestris) and coconut (C. nucisera) showed repellent action, however the efficacy of these oils was not much pronounced against Cx. quinquefasciatus. Results of statistical analysis revealed significant difference between vegetable and essential oils (p < 0.01) against tested species of mosquitoes. Essential oils were found marginally superior in repellancy than camphor and mylol (p < 0.01) against An. culicifacies and Cx. quinquefasciatus. PMID:8936292

  7. On Killing vector fields of a homogeneous and isotropic universe in closed model

    OpenAIRE

    Sharipov, Ruslan

    2007-01-01

    Killing vector fields of a closed homogeneous and isotropic universe are studied. It is shown that in general case there is no time-like Killing vector fields in such a universe. Two exceptional cases are revealed.

  8. Barrier screens: a method to sample blood-fed and host-seeking exophilic mosquitoes

    Directory of Open Access Journals (Sweden)

    Burkot Thomas R

    2013-02-01

    Full Text Available Abstract Background Determining the proportion of blood meals on humans by outdoor-feeding and resting mosquitoes is challenging. This is largely due to the difficulty of finding an adequate and unbiased sample of resting, engorged mosquitoes to enable the identification of host blood meal sources. This is particularly difficult in the south-west Pacific countries of Indonesia, the Solomon Islands and Papua New Guinea where thick vegetation constitutes the primary resting sites for the exophilic mosquitoes that are the primary malaria and filariasis vectors. Methods Barrier screens of shade-cloth netting attached to bamboo poles were constructed between villages and likely areas where mosquitoes might seek blood meals or rest. Flying mosquitoes, obstructed by the barrier screens, would temporarily stop and could then be captured by aspiration at hourly intervals throughout the night. Results In the three countries where this method was evaluated, blood-fed females of Anopheles farauti, Anopheles bancroftii, Anopheles longirostris, Anopheles sundaicus, Anopheles vagus, Anopheles kochi, Anopheles annularis, Anopheles tessellatus, Culex vishnui, Culex quinquefasciatus and Mansonia spp were collected while resting on the barrier screens. In addition, female Anopheles punctulatus and Armigeres spp as well as male An. farauti, Cx. vishnui, Cx. quinquefasciatus and Aedes species were similarly captured. Conclusions Building barrier screens as temporary resting sites in areas where mosquitoes were likely to fly was an extremely time-effective method for collecting an unbiased representative sample of engorged mosquitoes for determining the human blood index.

  9. Understanding the DNA damage response in order to achieve desired gene editing outcomes in mosquitoes.

    Science.gov (United States)

    Overcash, Justin M; Aryan, Azadeh; Myles, Kevin M; Adelman, Zach N

    2015-02-01

    Mosquitoes are high-impact disease vectors with the capacity to transmit pathogenic agents that cause diseases such as malaria, yellow fever, chikungunya, and dengue. Continued growth in knowledge of genetic, molecular, and physiological pathways in mosquitoes allows for the development of novel control methods and for the continued optimization of existing ones. The emergence of site-specific nucleases as genomic engineering tools promises to expedite research of crucial biological pathways in these disease vectors. The utilization of these nucleases in a more precise and efficient manner is dependent upon knowledge and manipulation of the DNA repair pathways utilized by the mosquito. While progress has been made in deciphering DNA repair pathways in some model systems, research into the nature of the hierarchy of mosquito DNA repair pathways, as well as in mechanistic differences that may exist, is needed. In this review, we will describe progress in the use of site-specific nucleases in mosquitoes, along with the hierarchy of DNA repair in the context of mosquito chromosomal organization and structure, and how this knowledge may be manipulated to achieve precise chromosomal engineering in mosquitoes. PMID:25596822

  10. Molecular epidemiology of Japanese encephalitis virus in mosquitoes in Taiwan during 2005-2012.

    Science.gov (United States)

    Su, Chien-Ling; Yang, Cheng-Fen; Teng, Hwa-Jen; Lu, Liang-Chen; Lin, Cheo; Tsai, Kun-Hsien; Chen, Yu-Yu; Chen, Li-Yu; Chang, Shu-Fen; Shu, Pei-Yun

    2014-10-01

    Japanese encephalitis (JE) is a mosquito-borne zoonotic disease caused by the Japanese encephalitis virus (JEV). Pigs and water birds are the main amplifying and maintenance hosts of the virus. In this study, we conducted a JEV survey in mosquitoes captured in pig farms and water bird wetland habitats in Taiwan during 2005 to 2012. A total of 102,633 mosquitoes were collected. Culex tritaeniorhynchus was the most common mosquito species found in the pig farms and wetlands. Among the 26 mosquito species collected, 11 tested positive for JEV by RT-PCR, including Cx. tritaeniorhynchus, Cx. annulus, Anopheles sinensis, Armigeres subalbatus, and Cx. fuscocephala. Among those testing positive, Cx. tritaeniorhynchus was the predominant vector species for the transmission of JEV genotypes I and III in Taiwan. The JEV infection rate was significantly higher in the mosquitoes from the pig farms than those from the wetlands. A phylogenetic analysis of the JEV envelope gene sequences isolated from the captured mosquitoes demonstrated that the predominant JEV genotype has shifted from genotype III to genotype I (GI), providing evidence for transmission cycle maintenance and multiple introductions of the GI strains in Taiwan during 2008 to 2012. This study demonstrates the intense JEV transmission activity in Taiwan, highlights the importance of JE vaccination for controlling the epidemic, and provides valuable information for the assessment of the vaccine's efficacy. PMID:25275652

  11. Analysis of the metabolome of Anopheles gambiae mosquito after exposure to Mycobacterium ulcerans.

    Science.gov (United States)

    Hoxmeier, J Charles; Thompson, Brice D; Broeckling, Corey D; Small, Pamela; Foy, Brian D; Prenni, Jessica; Dobos, Karen M

    2015-01-01

    Infection with Mycobacterium ulcerans causes Buruli Ulcer, a neglected tropical disease. Mosquito vectors are suspected to participate in the transmission and environmental maintenance of the bacterium. However, mechanisms and consequences of mosquito contamination by M. ulcerans are not well understood. We evaluated the metabolome of the Anopheles gambiae mosquito to profile the metabolic changes associated with bacterial colonization. Contamination of mosquitoes with live M. ulcerans bacilli results in disruptions to lipid metabolic pathways of the mosquito, specifically the utilization of glycerolipid molecules, an affect that was not observed in mosquitoes exposed to dead M. ulcerans. These results are consistent with aberrations of lipid metabolism described in other mycobacterial infections, implying global host-pathogen interactions shared across diverse saprophytic and pathogenic mycobacterial species. This study implicates features of the bacterium, such as the putative M. ulcerans encoded phospholipase enzyme, which promote virulence, survival, and active adaptation in concert with mosquito development, and provides significant groundwork for enhanced studies of the vector-pathogen interactions using metabolomics profiling. Lastly, metabolic and survival data suggest an interaction which is unlikely to contribute to transmission of M. ulcerans by A. gambiae and more likely to contribute to persistence of M. ulcerans in waters cohabitated by both organisms. PMID:25784490

  12. The relevance and applicability of oocyst prevalence as a read-out for mosquito feeding assays

    Science.gov (United States)

    Stone, Will J. R.; Eldering, Maarten; van Gemert, Geert-Jan; Lanke, Kjerstin H. W.; Grignard, Lynn; van de Vegte-Bolmer, Marga G.; Siebelink-Stoter, Rianne; Graumans, Wouter; Roeffen, Will F. G.; Drakeley, Chris J.; Sauerwein, Robert W.; Bousema, Teun

    2013-12-01

    Mosquito feeding assays are important in evaluations of malaria transmission-reducing interventions. The proportion of mosquitoes with midgut oocysts is commonly used as an outcome measure, but in natural low intensity infections the effect of oocyst non-rupture on mosquito infectivity is unclear. By identifying ruptured as well as intact oocysts, we show that in low intensity P. falciparum infections i) 66.7-96.7% of infected mosquitoes experienced oocyst rupture between 11-21 days post-infection, ii) oocyst rupture led invariably to sporozoite release, iii) oocyst rupture led to salivary gland infections in 97.8% of mosquitoes, and iv) 1250 (IQR 313-2400) salivary gland sporozoites were found per ruptured oocyst. These data show that infectivity can be predicted with reasonable certainty from oocyst prevalence in low intensity infections. High throughput methods for detecting infection in whole mosquitoes showed that 18s PCR but not circumsporozoite ELISA gave a reliable approximation of mosquito infection rates on day 7 post-infection.

  13. Biological control of mosquitoes in scrap tires in Brownsville, Texas, USA and Matamoros, Tamaulipas, Mexico.

    Science.gov (United States)

    Uejio, Christopher K; Hayden, Mary H; Zielinski-Gutierrez, Emily; Lopez, Jose Luis Robles; Barrera, Roberto; Amador, Manuel; Thompson, Gregory; Waterman, Stephen H

    2014-06-01

    Dengue periodically circulates in southern Texas and neighboring Tamaulipas, Mexico; thus, a closer examination of human and vector ecology at the northern limits of North American transmission may improve prevention activities. Scrap tires produce large mosquito populations and increase the risk of dengue transmission. Some households choose not to pay tire disposal fees, and many tires are illegally dumped in residential areas. Biological control may provide low-cost and environmentally friendly mosquito control. This pilot study evaluated the ability of Mesocyclops longisetus to reduce mosquito populations in existing residential scrap tire piles. Mosquito populations were measured by the number of all mosquito pupae within tires or adult Aedes aegypti and Ae. albopictus near piles. Mesocyclops longisetus treated piles did not significantly reduce total mosquito pupae (P = 0.07) in Matamoros, Mexico. The study also evaluated the efficacy of native Toxorhynchites moctezuma which preferentially colonized tire piles under vegetation cover in Brownsville, TX. Toxorhynchites moctezuma larvae significantly reduced total mosquito pupae, but the strength of control diminished over time. PMID:25102598

  14. Influence of density on intraguild predation of aquatic Hemiptera (Heteroptera: implications in biological control of mosquito

    Directory of Open Access Journals (Sweden)

    S. Brahma

    2014-04-01

    Full Text Available The water bugs Diplonychus rusticus (Fabricius (Heteroptera: Belostomatidae and Anisops bouvieri (Kirkaldy (Heteroptera: Notonectidae co-occur in wetlands sharing mosquito larvae as prey. As a consequence, an asymmetrical intraguild predation (IGP involving D. rusticus as IG predator and A. bouvieri as IG prey can be possible, the outcome of which may vary with the relative density of interacting species. Based on this proposition density dependent effects on the IG prey and shared prey mortality were assessed in the laboratory using varying numbers of IG predator and shared prey (IV instar Culex quinquefasciatus larva. In contrast to single predator system, mosquito larvae were proportionately less vulnerable to predation in IGP, at low density of shared prey. An increase in density of mosquito decreased the mortality of IG prey (A. bouvieri, but the mean mortality of the IG prey increased with the density of IG predator, in IGP system. Increase in density of mosquito and D. rusticus enhanced risk to predation of mosquito while reducing the mortality of A. bouvieri. Interaction between D. rusticus and A. bouvieri as a part of IGP system provides a possible reason of coexistence of mosquito immature along with predators in wetlands. Biological regulation of mosquitoes may be affected, if appropriate predator numbers are not available in the habitats.

  15. Analysis of the metabolome of Anopheles gambiae mosquito after exposure to Mycobacterium ulcerans

    Science.gov (United States)

    Hoxmeier, J. Charles; Thompson, Brice D.; Broeckling, Corey D.; Small, Pamela; Foy, Brian D.; Prenni, Jessica; Dobos, Karen M.

    2015-01-01

    Infection with Mycobacterium ulcerans causes Buruli Ulcer, a neglected tropical disease. Mosquito vectors are suspected to participate in the transmission and environmental maintenance of the bacterium. However, mechanisms and consequences of mosquito contamination by M. ulcerans are not well understood. We evaluated the metabolome of the Anopheles gambiae mosquito to profile the metabolic changes associated with bacterial colonization. Contamination of mosquitoes with live M. ulcerans bacilli results in disruptions to lipid metabolic pathways of the mosquito, specifically the utilization of glycerolipid molecules, an affect that was not observed in mosquitoes exposed to dead M. ulcerans. These results are consistent with aberrations of lipid metabolism described in other mycobacterial infections, implying global host-pathogen interactions shared across diverse saprophytic and pathogenic mycobacterial species. This study implicates features of the bacterium, such as the putative M. ulcerans encoded phospholipase enzyme, which promote virulence, survival, and active adaptation in concert with mosquito development, and provides significant groundwork for enhanced studies of the vector-pathogen interactions using metabolomics profiling. Lastly, metabolic and survival data suggest an interaction which is unlikely to contribute to transmission of M. ulcerans by A. gambiae and more likely to contribute to persistence of M. ulcerans in waters cohabitated by both organisms. PMID:25784490

  16. Web mapping GIS: GPS under the GIS umbrella for Aedes species dengue and chikungunya vector mosquito surveillance and control

    Directory of Open Access Journals (Sweden)

    M. Palaniyandi

    2014-09-01

    Full Text Available The mosquito nuisance and the mosquito borne diseases have become major important challenging public health problems in India especially in the fast developing city like Pondicherry urban agglomeration. The Pondicherry government has been implemented full-fledged mosquito control measures, however, dengue and chikungunya epidemics was accelerating trend in Pondicherry for the recent years, and therefore, the directorate of public health, Pondicherry was requested vector control research centre (VCRC, to conduct a mosquito control evaluation survey. A team of field staff of VCRC headed by the author, Pondicherry, have conducted a detailed reconnaissance survey for collecting the site specifications of houses and the streetwise mosquito data for analyzing the density of vector mosquitoes in the wards / blocks and delineating the areas vulnerable to disease epidemics in the urban areas. The GPS GARMIN 12 XL was used to collect the field data. The ARC GIS 10.0 software was used to map the site locations (houses with mosquito’s data. The digital map of block boundary of Pondicherry was used for mapping purpose. A systematic grid sampling was applied to conduct a rapid survey for mapping Aedes species mosquito genic condition in the urban areas and the coordinates of sites of house information with breeding habitats positive in the grid sectors was collected using GPS, and the mean value of positive habitats was analyzed by quintiles method for mapping. The four blocks were selected for Aedes mosquito survey where the mosquito problem was identified as comparatively high, four numbers of wards were selected from each block, and the 40 number of houses was selected with 100 meter interval distance for mosquito breeding survey in the domestic and peripheral domestic areas in each wards. The problematic areas were identified, highlighted and recommended for web mapping GIS for Aedes mosquito surveillance continuously for monitoring the mosquito control measures in the Pondicherry urban areas and the other parts of the urban areas in the country.

  17. Spacetimes with Killing tensors. [for Einstein-Maxwell fields with certain spinor indices

    Science.gov (United States)

    Hughston, L. P.; Sommers, P.

    1973-01-01

    The characteristics of the Killing equation and the Killing tensor are discussed. A conformal Killing tensor is of interest inasmuch as it gives rise to a quadratic first integral for null geodesic orbits. The Einstein-Maxwell equations are considered together with the Bianchi identity and the conformal Killing tensor. Two examples for the application of the considered relations are presented, giving attention to the charged Kerr solution and the charged C-metric.

  18. Are U.S drone targeted killings within the confines of the law?

    OpenAIRE

    Chengeta, Thompson

    2011-01-01

    Equally discomforting is the PlayStation mentality that surrounds drone killings. Young military personnel raised on a diet of video games now kill real people remotely using joysticks. Far removed from the human consequences of their actions, how will this generation of fighters value the right to life? How will commanders and policy makers keep themselves immune from the deceptively antiseptic nature of drone killings? Will killing be a more attractive option than capture? Wi...

  19. Mechanism of electrical enhancement of efficacy of antibiotics in killing biofilm bacteria.

    OpenAIRE

    Costerton, J W; Ellis, B.; LAM, K; Johnson, F; Khoury, A E

    1994-01-01

    The bioelectric effect, in which electric fields are used to enhance the efficacy of biocides and antibiotics in killing biofilm bacteria, has been shown to reduce the very high concentrations of these antibacterial agents needed to kill biofilm bacteria to levels very close to those needed to kill planktonic (floating) bacteria of the same species. In this report, we show that biofilm bacteria are readily killed by an antibiotic on all areas of the active electrodes and on the surfaces of co...

  20. Space and the persistence of male-killing endosymbionts in insect populations.

    OpenAIRE

    Groenenboom, Maria A C; Hogeweg, Paulien

    2002-01-01

    Male-killing bacteria are bacteria that are transmitted vertically through the females of their insect hosts. They can distort the sex ratio of their hosts by killing infected male offspring. In nature, male-killing endosymbionts (male killers) often have a 100% efficient vertical transmission, and multiple male-killing bacteria infecting a single population are observed. We use different model formalisms to study these observations. In mean-field models a male killer with perfect transmissio...

  1. Trogocytosis by Entamoeba histolytica contributes to cell killing and tissue invasion

    OpenAIRE

    Ralston, Katherine S.; Solga, Michael D.; Mackey-Lawrence, Nicole M; Somlata,; Bhattacharya, Alok; Petri, William A

    2014-01-01

    Entamoeba histolytica is the causative agent of amoebiasis, a potentially fatal diarrheal disease in the developing world. The parasite was named “histolytica” for its ability to destroy host tissues, which is most likely driven by direct killing of human cells. The mechanism of human cell killing has been unclear, though the accepted model was that the parasites use secreted toxic effectors to kill cells prior to ingestion1. Here we report the surprising discovery that amoebae kill by biting...

  2. Role of magnesium and a phagosomal P-type ATPase in intracellular bacterial killing

    OpenAIRE

    Lelong-favre Alborini, Emmanuelle; Marchetti, Anna; Gueho, Aure?lie; Lima, Wanessa C.; Sattler, Natascha; Molmeret, Mae?lle; Hagedorn, Monica; Soldati, Thierry; Cosson, Pierre

    2011-01-01

    Bacterial ingestion and killing by phagocytic cells are essential processes to protect the human body from infectious microorganisms. However, only few proteins implicated in intracellular bacterial killing have been identified to date. We used Dictyostelium discoideum, a phagocytic bacterial predator, to study intracellular killing. In a random genetic screen we identified Kil2, a type V P-ATPase as an essential element for efficient intracellular killing of Klebsiella pneumoniae bacteria. I...

  3. Susceptibility of mosquito and lepidopteran cell lines to the mosquito iridescent virus (IIV-3) from Aedes taeniorhynchus.

    Science.gov (United States)

    Becnel, James J; Pridgeon, Julia W

    2011-09-01

    Mosquito iridescent viruses (MIV) are members of the genus Chloriridovirus that currently contains only the type IIV-3 from Aedestaeniorhynchus. The complete genome of invertebrate iridescent virus -3 (IIV-3) has been sequenced and the availability of a tissue culture system would facilitate functional genomic studies. This investigation, using quantitative PCR and electron microscopy, has determined that the mosquito cell lines Aedes aegypti (Aag2), Aedes albopictus (C6/36) and Anopheles gambiae (4a3A) as well as the lepidopteran cell line from Spodoptera frugiperda (SF9) are permissive to IIV-3 infection. However, IIV-3 infection remained longer in Aag2 and C6/36 cells. Virus produced in C6/36 cell line was infectious to larvae of A. taeniorhynchus by injection and per os. Ultrastructural examination of 4a3A and SF9 cells infected with IIV-3 revealed an unusual feature, where virions were localized to mitochondria. It is speculated that containment with mitochondria may play a role in the lack of persistence in these cell lines. PMID:21741386

  4. Observações sobre os mosquitos Culex da cidade de São Paulo, Brasil Observations on Culex mosquitoes of S. Paulo City, Brazil

    Directory of Open Access Journals (Sweden)

    Oswaldo Paulo Forattini

    1973-12-01

    Full Text Available São apresentados os resultados obtidos na coleta de mosquitos do gênero Culex na área urbana da cidade de São Paulo, Brasil. Foram empregadas armadilhas luminosas automáticas tipo "New Jersey 50". Os resultados revelaram a presença de outras populações representadas principalmente por Culex chidesteri, C. dolosus e C. bidens as quais, em conjunto, chegaram algumas vezes a sobrepujar a de Culex pipiens fatigans. O maior rendimento foi obtido em áreas com abastecimento de água mas sem rede de esgotos. As coletas intradomiciliares revelaram franca predominância de C. pipiens fatigans.With the use of New Jersey-50 light traps, a survey of Culex mosquitoes was made in the urban área of São Paulo City, Brazil. Beside Culex pipiens fatigans several other species were found, mainly represented by Culex chidesteri, C. dolosus and C. bidens. The combined incidence of these three populations follows nearly the fatigans one and frequently exceeding it. The most high levels of density were found at areas with water treatment but without sewage disposal. Domiciliary collections showed great Culex pipiens fatigans predominancy.

  5. 40 CFR 180.1108 - Delta endotoxin of Bacillus thuringiensis variety San Diego encapsulated into killed Pseudomonas...

    Science.gov (United States)

    2010-07-01

    ...variety San Diego encapsulated into killed Pseudomonas fluorescens; exemption from the requirement...San Diego encapsulated into killed Pseudomonas fluorescens; exemption from the requirement...San Diego encapsulated into killed Pseudomonas fluorescens is exempt from the...

  6. Mosquito feeding affects larval behaviour and development in a moth

    OpenAIRE

    Martel, Ve?ronique; Schlyter, Fredrik; Ignell, Rickard; Hansson, Bill S.; Anderson, Peter

    2011-01-01

    Organisms are attacked by different natural enemies present in their habitat. While enemies such as parasitoids and predators will kill their hosts/preys when they successfully attack them, enemies such as micropredators will not entirely consume their prey. However, they can still have important consequences on the performance and ecology of the prey, such as reduced growth, increased emigration, disease transmission. In this paper, we investigated the impact of a terrestrial micropredator, ...

  7. Landscape Effects on the Presence, Abundance and Diversity of Mosquitoes in Mediterranean Wetlands.

    Science.gov (United States)

    Roiz, David; Ruiz, Santiago; Soriguer, Ramon; Figuerola, Jordi

    2015-01-01

    Environment determines the distribution of mosquito-borne diseases in that it influences the vector-host-pathogen transmission cycle, including vector distribution, abundance and diversity. In this study, we analyse the relationship between environmental variables estimated by remote sensing and the spatial distribution (presence, abundance and diversity) of seven mosquito species vectors of West Nile and other pathogens (Usutu, avian malaria and dirofilariasis) in the Doñana Natural Park, Spain. Traps were distributed over an area of 54,984 ha divided into six ecological units: marshland, sand dunes, scrubland, ricefields, crops and fishponds. We collected mosquitoes once a month from up to 112 locations using BG-Sentinel traps baited with BG-lure and CO2 during March-November 2010. Hydroperiod, NDVI and Inundation surface were estimated at several resolution scales (100, 250, 500, 1000 and 2000 metres) from corrected and normalized Landsat Images. We sampled 972,346 female mosquitoes, the most abundant species being Culex theileri, Ochlerotatus caspius, Culex modestus, Culex perexiguus, Culex pipiens, Anopheles atroparvus and Ochlerotatus detritus. Our results suggest that: (1) hydroperiod, inundation surface and NDVI are strongly related to the spatial distribution of mosquitoes; (2) the spatial scales used to measure these variables affected quantification of these relationships, the larger scale being more informative; (3) these relationships are species-specific; (4) hydroperiod is negatively related to mosquito presence and richness; (5) Culex abundance is positively related to hydroperiod; (6) NDVI is positively related to mosquito diversity, presence and abundance, except in the case of the two salt marsh species (Oc. caspius and Oc. detritus); and (7) inundation surfaces positively condition the abundance and richness of most species except the salt marsh mosquitoes. Remote sensing data provided reliable information for monitoring mosquito populations. Landscape significantly affected mosquito distribution and abundance, and as a result may alter disease risk. These results suggest that while environmental conditions affect the distribution and abundance of mosquitoes, other factors such as human modification of landscapes may give rise to significant changes in mosquito populations and consequently disease risk. PMID:26086804

  8. Investigation of Mosquito Survival Associated with Bacillus thuringensis israelensis and Aquatic Plant, Lemna minor

    Directory of Open Access Journals (Sweden)

    Abdullah D. Altalhi

    2005-01-01

    Full Text Available This research was aimed to study the significance of the mixture from the aquatic plant, duck weed and Bacillus thuringensis israelensis as a potent deterrent factor limiting mosquito Culex pipiens populations in the field. C. pipiens mosquito appeared highly sensitivity for the higher concentrations (ppm of Bacillus thuringensis israelensis (Bti; 100% mortality was recorded in the third and fourth instar larvae after treated by 90 and 9 ppm, respectively. The third and fourth instar larvae were appeared high susceptible to the allelochemicals of duckweed, Lemna minor. Water half covered by duckweed increase the efficacy of Bti. on the third and fourth instar larvae of mosquito.

  9. Aromatic plant-derived essential oil: an alternative larvicide for mosquito control.

    Science.gov (United States)

    Pitasawat, B; Champakaew, D; Choochote, W; Jitpakdi, A; Chaithong, U; Kanjanapothi, D; Rattanachanpichai, E; Tippawangkosol, P; Riyong, D; Tuetun, B; Chaiyasit, D

    2007-04-01

    Five aromatic plants, Carum carvi (caraway), Apium graveolens (celery), Foeniculum vulgare (fennel), Zanthoxylum limonella (mullilam) and Curcuma zedoaria (zedoary) were selected for investigating larvicidal potential against mosquito vectors. Two laboratory-reared mosquito species, Anopheles dirus, the major malaria vector in Thailand, and Aedes aegypti, the main vector of dengue and dengue hemorrhagic fever in urban areas, were used. All of the volatile oils exerted significant larvicidal activity against the two mosquito species after 24-h exposure. Essential oil from mullilam was the most effective against the larvae of A. aegypti, while A. dirus larvae showed the highest susceptibility to zedoary oil. PMID:17337133

  10. Stochastic quantisation and killing symmetries of random systems

    International Nuclear Information System (INIS)

    Recent results about the supersymmetries of random systems governed by stochastic differential equations have classical analogues in terms of geometrical symmetries in the configuration space of commuting variables. The related results are: (1) The reversible drift velocity of a stationary stochastic process in a Killing vector of the diffusion metric; (2) the irreversible drift velocity is a geodesic tangent vector; (3) the stationary current conservation equation is a special case of the general result that scalar products of Killing vectors with geodesic tangent vectors are constants of the motion. The physical postulate is that microscopic reversibility is to the normality of time translation generators what time reversal invariance is to the hermiticity of hamiltonians. (orig.)

  11. An evaluation of sex-age-kill (SAK) model performance

    Science.gov (United States)

    Millspaugh, Joshua J.; Skalski, John R.; Townsend, Richard L.; Diefenbach, Duane R.; Boyce, Mark S.; Hansen, Lonnie P.; Kammermeyer, Kent

    2009-01-01

    The sex-age-kill (SAK) model is widely used to estimate abundance of harvested large mammals, including white-tailed deer (Odocoileus virginianus). Despite a long history of use, few formal evaluations of SAK performance exist. We investigated how violations of the stable age distribution and stationary population assumption, changes to male or female harvest, stochastic effects (i.e., random fluctuations in recruitment and survival), and sampling efforts influenced SAK estimation. When the simulated population had a stable age distribution and ? > 1, the SAK model underestimated abundance. Conversely, when ? Sex-age-kill estimates may be precise at large spatial scales, such as the state level, but less so at the individual management unit level. Alternative models, such as statistical age-at-harvest models, which require similar data types, might allow for more robust, broad-scale demographic assessments.

  12. A Research for Massive Fish Kills in Lake Bafa (Turkey

    Directory of Open Access Journals (Sweden)

    Murat Yabanl?

    2011-06-01

    Full Text Available As there were massive fish kills in Lake Bafa which is a lagoon situated in Southwestern Turkey in October, 2006, water and fish samples were taken from the region. Water samples were analysed physicochemically, toxicologically and microbiologically and fish samples were subjected to toxicological analysis. The analyses of lake water revealed on oxygen value of approximately 5.0 mg/L, salinity 16.2 ?, nitrogen from ammonia 0.1 mg/L, nitrogen nitrite 0.013 mg/L, and total organic carbon 13 mg/L. Total coliform count was 1100 MPN/100 ml and faecal coliform count was 28 MPN/100 ml. There was no detection of any pesticide residues in fish and water samples. Massive fish kills are thought to be due to the decrease in water quality.

  13. Scientific projection paper for mutagenesis, transformation and cell killing

    International Nuclear Information System (INIS)

    Our knowledge about mutagenesis, transformation, and cell killing by ionizing radiation consists of large bodies of data, which are potentially useful in terms of application to human risk assessment and to the constructive use of radiation, as in cancer treatment. The three end-points discussed above are united by at least five significant concepts in radiation research strategy: (1) The inter-relationships among the important end-points, mutation, carcinogenesis, and cell killing. Research on one is meaningful only in the context of information about the other two. (2) The interaction of radiations with other agents in producing these end-points. (3) The mechanisms of action of other environmental mutagenic, carcinogenic, and cytotoxic agents. (4) The use of repair deficient human mutant cells. (5) The study of radiation damage mechanisms. There is no better way to extrapolate laboratory data to the clinical and public worlds than to understand the underlying biological mechanisms that produced the data

  14. New Geometry with All Killing Vectors Spanning the Poincaré Algebra

    International Nuclear Information System (INIS)

    The new four-dimensional geometry whose Killing vectors span the Poincaré algebra is presented and its structure is analyzed. The new geometry can be regarded as the Poincaré-invariant solution of the degenerate extension of the vacuum Einstein field equations with a negative cosmological constant and provides a static cosmological spacetime with a Lobachevsky space. The motion of free particles in the spacetime is discussed. (general)

  15. Ozone production by amino acids contributes to killing of bacteria

    OpenAIRE

    Yamashita, Kouhei; Miyoshi, Takashi; Arai, Toshiyuki; Endo, Nobuyuki; Itoh, Hiroshi; Makino, Keisuke; Mizugishi, Kiyomi; Uchiyama, Takashi; Sasada, Masataka

    2008-01-01

    Reactive oxygen species produced by phagocytosing neutrophils are essential for innate host defense against invading microbes. Previous observations revealed that antibody-catalyzed ozone formation by human neutrophils contributed to the killing of bacteria. In this study, we discovered that 4 amino acids themselves were able to catalyze the production of an oxidant with the chemical signature of ozone from singlet oxygen in the water-oxidation pathway, at comparable level to antibodies. The ...

  16. Gauge-covariant extensions of Killing tensors and conservation laws

    CERN Document Server

    van Holten, J W

    2014-01-01

    In classical and quantum mechanical systems on manifolds with gauge-field fluxes, constants of motion are constructed from gauge-covariant extensions of Killing vectors and tensors. This construction can be carried out using a manifestly covariant procedure, in terms of covariant phase space with a covariant generalization of the Poisson brackets, c.q. quantum commutators. Some examples of this construction are presented.

  17. Gauge-covariant extensions of Killing tensors and conservation laws

    Science.gov (United States)

    van Holten, Jan-Willem

    2015-04-01

    In classical and quantum mechanical systems on manifolds with gauge-field fluxes, constants of motion are constructed from gauge-covariant extensions of Killing vectors and tensors. This construction can be carried out using a manifestly covariant procedure, in terms of covariant phase space with a covariant generalization of the Poisson brackets, c.q. quantum commutators. Some examples of this construction are presented.

  18. Entropy from near-horizon geometries of Killing horizons

    CERN Document Server

    Dreyer, Olaf; Ghosh, Avirup

    2014-01-01

    We derive black hole entropy based on the near-horizon symmetries of black hole space-times. To derive these symmetries we make use of an $(R,T)$-plane close to a Killing horizon. We identify a set of vector fields that preserves this plane and forms a Witt algebra. The corresponding algebra of Hamiltonians is shown to have a non-trivial central extension. Using the Cardy formula and the central charge we obtain the Bekenstein-Hawking entropy.

  19. Black holes with a single Killing vector field: black resonators

    OpenAIRE

    Dias, Oscar J. C.; Santos, Jorge E.; Way, Benson

    2015-01-01

    We numerically construct asymptotically anti-de Sitter (AdS) black holes in four dimensions that contain only a single Killing vector field. These solutions, which we coin black resonators, link the superradiant instability of Kerr-AdS to the nonlinear weakly turbulent instability of AdS by connecting the onset of the superradiance instability to smooth, horizonless geometries called geons. Furthermore, they demonstrate non-uniqueness of Kerr-AdS by sharing asymptotic charge...

  20. Estimation in discretely observed diffusions killed at a threshold

    OpenAIRE

    Bibbona, Enrico; Ditlevsen, Susanne

    2010-01-01

    Parameter estimation in diffusion processes from discrete observations up to a first-hitting time is clearly of practical relevance, but does not seem to have been studied so far. In neuroscience, many models for the membrane potential evolution involve the presence of an upper threshold. Data are modeled as discretely observed diffusions which are killed when the threshold is reached. Statistical inference is often based on the misspecified likelihood ignoring the presence ...