The Hengduan Mountains region of south-west China is a noted biodiversity,hotspot, but the geographic origins and historical assembly of its rich endemic flora, including the sky-island species ofSolms-laubachia Musch...The Hengduan Mountains region of south-west China is a noted biodiversity,hotspot, but the geographic origins and historical assembly of its rich endemic flora, including the sky-island species ofSolms-laubachia Muschl. （Brassicaceae）, have been little studied. Previous molecular studies on the phylogeny of Solms-laubachia showed it to be paraphyletic, leading to considerable expansion not only of its taxonomic limits, but also its geographic range, with the inclusion of taxa from outside the Hengduan region. However, these studies provided little resolution of interspecific relationships, preventing inferences about historical biogeography within the clade. In the present study, new sequence data from two nuclear genes （LEAFY and G3pdh） and two chloroplast intergenic spacers （petN-psbM and psbM-trnD） were combined with existing markers to increase phylogenetic signals. Phaeonychium villosum （Maxim.） Al-Shehbaz was found to be nested within Solms-laubachia s.l. In general, phylogenetic relationships appear to be a good predictor of geography, with the Hengduan Mountain endemics embedded in a paraphyletic grade of species from the western Himalayas and central Asia, but they also imply morphological homoplasy, lncongruence was detected between the nuclear and chloroplast gene trees, perhaps resulting from incomplete lineage sorting of ancestral polymorphisms. The crown age ofSolms-laubachia s.l. was estimated to be approximately 1.42-3.68 mya, using Bayesian relaxed molecular clock analysis. Historical biogeographic analysis using a parametric dispersalextinction-cladogenesis model inferred central Asia and the western Himalayas as most probable ancestral range of Solms-laubachia s.l., and estimated higher rates of eastward expansion than westward during the diversification of descendant lineages. In summary, our results suggest that Solms-laubachia s.l. originated during the Pliocene in central Asia, and subsequently migrated eastward into the Hengduan Mountains, colonizing sky-island, alpine scree-slope habitats that may have provided novel ecological opportunity and accelerated speciation, ultimately establishing this region as the present center of diversity of the genus.展开更多
The standard methods for regression analyses of clustered riverine larval habitat data of Simulium damnosum s.l.a major black-fly vector of onchoceriasis,postulate models relating observational ecological-sampled para...The standard methods for regression analyses of clustered riverine larval habitat data of Simulium damnosum s.l.a major black-fly vector of onchoceriasis,postulate models relating observational ecological-sampled parameter estimators to prolific habitats without accounting for residual intra-cluster error correlation effects.Generally,this correlation comes from two sources:(1)the design of the random effects and their assumed covariance from the multiple levels within the regression model and(2)the correlation structure of the residuals.Unfortunately,inconspicuous errors in residual intracluster correlation estimates can overstate precision in forecasted S.damnosum s.l.riverine larval habitat explanatory attributes regardless how they are treated(e.g.independent,autoregressive,Toeplitz,etc.).In this research,the geographical locations for multiple riverine-based S.damnosum s.l.larval ecosystem habitats sampled from two preestablished epidemiological sites in Togo were identified and recorded from July 2009 to June 2010.Initially,the data were aggregated into PROC GENMOD.An agglomerative hierarchical residual cluster-based analysis was then performed.The sampled clustered study site data was then analyzed for statistical correlations using monthly biting rates(MBR).Euclidean distance measurements and terrain-related geomorphological statistics were then generated in ArcGIS.A digital overlay was then performed also in ArcGIS using the georeferenced ground coordinates of high and low density clusters stratified by annual biting rates(ABR).The data was overlain onto multitemporal sub-meter pixel resolution satellite data(i.e.QuickBird 0.61m wavbands).Orthogonal spatial filter eigenvectors were then generated in SAS/Geographic Information Systems(GIS).Univariate and nonlinear regression-based models(i.e.logistic,Poisson,and negative binomial)were also employed to determine probability distributions and to identify statistically significant parameter estimators from the sampled data.Thereafter,Durbin–Watson statistics were used to test the null hypothesis that the regression residuals were not autocorrelated against the alternative that the residuals followed an autoregressive process in AUTOREG.Bayesian uncertainty matrices were also constructed employing normal priors for each of the sampled estimators in PROC MCMC.The residuals revealed both spatially structured and unstructured error effects in the high and low ABR-stratified clusters.The analyses also revealed that the estimators,levels of turbidity,and presence of rocks were statistically significant for the high-ABR-stratified clusters,while the estimators distance between habitats and floating vegetation were important for the low-ABR-stratified cluster.Varying and constant coefficient regression models,ABRstratified GIS-generated clusters,sub-meter resolution satellite imagery,a robust residual intra-cluster diagnostic test,MBR-based histograms,eigendecomposition spatial filter algorithms,and Bayesian matrices can enable accurate autoregressive estimation of latent uncertainity affects and other residual error probabilities(i.e.heteroskedasticity)for testing correlations between georeferenced S.damnosum s.l.riverine larval habitat estimators.The asymptotic distribution of the resulting residual adjusted intra-cluster predictor error autocovariate coefficients can thereafter be established while estimates of the asymptotic variance can lead to the construction of approximate confidence intervals for accurately targeting productive S.damnosum s.l.habitats based on spatiotemporal field-sampled count data.展开更多
A molecular phylogenetic analysis of the genus Corchorus(Grewioideae,Malvaceae s.l.)is presented,based on sequences of the nuclear ribosomal DNA internal transcribed spacer(ITS)region for 144 accessions representing 4...A molecular phylogenetic analysis of the genus Corchorus(Grewioideae,Malvaceae s.l.)is presented,based on sequences of the nuclear ribosomal DNA internal transcribed spacer(ITS)region for 144 accessions representing 47 species.Several other genera from the subfamily Grewioideae,namely Pseudocorchorus,Triumfetta,Sparrmannia,Entelea,and Grewia,were included as outgroups.The monophyly of the genus was well supported by all phylogenetic analyses(maximum likelihood,Bayesian approaches,and parsimony),and Corchorus was divided into four major clades.The majority of African species formed a statistically highly supported and distinct clade separated from the other pantropically distributed species.Several endemic species from Australia,New Caledonia,and tropical America were nested within this distinct clade,indicating dispersal from Africa to the rest of the pantropics.Based on the taxa included in this study,the two cultivated species(C.olitorius and C.capsularis)shared a common ancestry with wild species of C.africanus,C.brevicornatus,C.pseudocapsularis,C.pseudo-olitorius,C.urticifolius,C.pilosus,C.orinocensis,and C.cunninghamii.Pseudocorchorus,previously considered an accepted genus,was nested within the genus Corchorus and shared a common ancestry especially with C.depressus and C.siliquosus.Based on morphological and anatomical similarity as well as the results of the present molecular findings,inclusion of the six Pseudocorchorus species into Corchorus is proposed,with Pseudocorchorus as a synonym of Corchorus.Of the included outgroup taxa,Triumfetta is the closest sister to Corchorus,while the common ancestor of Corchorus/Pseudocorchorus,Triumfetta,Sparrmannia,and Entelea is Grewia.A further phylogenetic study with more taxa mainly from Australia,together with additional molecular markers and morphological investigation,would help to test the hypothesis on the biogeography and growth form evolution of the genus Corchorus.展开更多
Using a geographic information system (GIS), the relations between a georeferenced data set of Culex pipiens s.l. collected in Portugal mainland during seven years (2006-2012) and meteorological and physiographic para...Using a geographic information system (GIS), the relations between a georeferenced data set of Culex pipiens s.l. collected in Portugal mainland during seven years (2006-2012) and meteorological and physiographic parameters are evaluated. This work is one of the results of a long-term surveillance program of pernicious insects that act as vectors of various diseases;its focus is on the possibility of prevention that can be achieved with abundance data. The focus on Culex pipiens is justified by its abundance and its competence as a vector for numerous health issues. The cumulative distribution of monthly captures by each meteorological parameter allows to compute thresholds corresponding to mosquito massive presence related to 90% of the captures. Using the weather parameters measured in the network of weather stations across the country, a monthly average of each parameter of interest (temperature, humidity, etc.) is computed and an interpolation of the results is made to produce raster maps corresponding to each month. The previously obtained thresholds are applied to each map, producing spatial masks with the relevant zones for each parameter. The intersection of the various masks for each month shows the most densely populated area of Culex, and the ensemble allows us to observe the evolution of mosquito presence through the critical season, which is from May to October at these latitudes. In parallel, mosquito abundance data are related to physiographic parameters. The relative distribution of female mosquitoes across land cover types in each month allows identifying which classes and seasons are most relevant. Orthometric altitude related to the presence of 90% of the catches shows the limits reached by mosquitoes in each month. The results are applied to the previously obtained climate envelopes, delimiting critical areas where the level of risk of transmission of the pathogens for which Culex pipiens is a competent vector is high and countermeasures should be concentrated, allowing its planning, and targeting on a monthly basis. The described procedure can be used with other relevant vectors in any region of the world, whenever abundance data is available.展开更多
<strong>Background: </strong><span><span><span><span>With the rapid expansion of insecticide resistance limiting the effectiveness of insecticide-based vector control interventions,...<strong>Background: </strong><span><span><span><span>With the rapid expansion of insecticide resistance limiting the effectiveness of insecticide-based vector control interventions, integrated control strategies associating larviciding could be appropriate to improve current control efforts. The present experimental study assesses laboratory and field efficacy of the larvicide </span></span></span></span><span><span><span><span>VectoMax</span></span></span></span><span><span><span><span style="color:#111111;font-family:Roboto, sans-serif;font-size:16px;white-space:normal;background-color:#FFFFFF;"><sup>®</sup></span></span></span></span><span><span><span><span>G</span></span></span></span><span><span><span><span> on <i>Anopheline</i> and <i>Culicine</i> larval stages in Yaoundé. <strong>Methods:</strong> The effect of the larvicide </span></span></span></span><span><span><span><span>VectoMax</span></span></span></span><span><span><span><span style="color:#111111;font-family:Roboto, sans-serif;font-size:16px;white-space:normal;background-color:#FFFFFF;"><sup>®</sup></span></span></span></span><span><span><span><span>G,</span></span></span></span><span><span><span><span> a combination of <i>Bacillus</i><span> <i>thuringiensis</i> var. <i>israelensis</i> </span>(<i>Bti</i>) </span></span></span></span><span><span><span><span>and <i>Bacillus</i> <i>sphaericus</i> (<i>Bs</i>),</span></span></span></span><span><span><span><span> on larval development was assessed during both laboratory and open field trial experiments. Laboratory experiments permitted the evaluation of five different concentrations with four replicates/experiments. Laboratory experiments were conducted with <i>Anopheles</i> <i>coluzzii</i> “Ngousso” and <i>Culex</i> <i>quinquefasciatus</i> laboratory strains. Open field trials were conducted using </span></span></span></span><span><span><span><span>sixteen plastic containers with a diameter of 0.31 m buried in an array of four rows with 4 containers each. Distance between rows and between containers in a row was 1 meter. This experiment permitted to </span></span></span></span><span><span><span><span>test the effect of the microbial larvicide </span></span></span></span><span><span><span><span>VectoMax</span></span></span></span><span><span><span><span style="color:#111111;font-family:Roboto, sans-serif;font-size:16px;white-space:normal;background-color:#FFFFFF;"><sup>®</sup></span></span></span></span><span><span><span><span>G</span></span></span></span><span><span><span><span> under operational application conditions on field mosquito populations. <strong>Results:</strong> <span>The time to induce 100% mortality after exposure to serial concentrations of the larvicide varied according to the dose from 4 - 12 hours for <i>An.</i> <i>coluzzii</i> and 6 - 9 hours for <i>Cx.</i> <i>quinquefasciatus</i> in laboratory experiments. Measurements of the</span> residual activity indicated that all </span></span></span></span><span><span><span><span>VectoMax</span></span></span></span><span><span><span><span style="color:#111111;font-family:Roboto, sans-serif;font-size:16px;white-space:normal;background-color:#FFFFFF;"><sup>®</sup></span></span></span></span><span><span><span><span>G</span></span></span></span><span><span><span><span> concentrations were still active after 35 days and killed 86</span></span></span></span><span><span><span><span>% </span></span></span></span><span><span><span><span>-</span></span></span></span><span><span><span><span> </span></span></span></span><span><span><span><span>100% of larvae. Lethal dose of </span></span></span></span><span><span><span><span>VectoMax</span></span></span></span><span><span><span><span style="color:#111111;font-family:Roboto, sans-serif;font-size:16px;white-space:normal;background-color:#FFFFFF;"><sup>®</sup></span></span></span></span><span><span><span><span>G</span></span></span></span><span><span><span><span> killing 50% of larvae was estimated at 5.24 × 10<sup>-8</sup> mg/m<sup>2</sup> for <i>An.</i> <i>coluzzii</i> and 1.25 × 10<sup>-8</sup> mg/m<sup>2</sup> for <i>Cx.</i> <i>quinquefasciatus</i>. The lethal concentration inducing 95% mortality was estimated at 3.13 × 10<sup>-7</sup> mg/m<sup>2</sup> for <i>An.</i> <i>coluzzii</i> and 2.5 × 10<sup>-8</sup> <span>mg/m<sup>2</sup> for <i>Cx.</i> <i>quinquefasciatus</i>. Open field trials tests indicated that </span>sub-lethal concentrations of </span></span></span></span><span><span><span><span>VectoMax</span></span></span></span><span><span><span><span style="color:#111111;font-family:Roboto, sans-serif;font-size:16px;white-space:normal;background-color:#FFFFFF;"><sup>®</sup></span></span></span></span><span><span><span><span>G</span></span></span></span><span><span><span><span> successfully killed 100% <i>An.</i> <i>gambiae</i> s.l. larvae within 24 hours, while with <i>Culex</i> spp. larvae, 100% mortality was recorded after 48 hours post-treatment. Natural recolonization of water containers by larvae was recorded between 3 and 6 days respectively after the treatment with sublethal doses. Late instar larvae were recorded 5 and 6 days after treatment. When the jars were treated with reference dosage or supra doses of </span></span></span></span><span><span><span><span>VectoMax</span></span></span></span><span><span><span><span style="color:#111111;font-family:Roboto, sans-serif;font-size:16px;white-space:normal;background-color:#FFFFFF;"><sup>®</sup></span></span></span></span><span><span><span><span>G,</span></span></span></span><span><span><span><span> recolonization of water containers was observed six days after treatments. No pupae of both species were found 6 and 7 days post-treatment. <strong>Conclusions:</strong> The study indicated high efficacy of the microbial larvicide </span></span></span></span><span><span><span><span>VectoMax</span></span></span></span><span><span><span><span style="color:#111111;font-family:Roboto, sans-serif;font-size:16px;white-space:normal;background-color:#FFFFFF;"><sup>®</sup></span></span></span></span><span><span><span><span>G</span></span></span></span><span><span><span><span> against <i>Anopheline</i> and <i>Culex</i> larvae. Microbial larvicides such as </span></span></span></span><span><span><span><span>VectoMax</span></span></span></span><span><span><span><span style="color:#111111;font-family:Roboto, sans-serif;font-size:16px;white-space:normal;background-color:#FFFFFF;"><sup>®</sup></span></span></span></span><span><span><span><span>G</span></span></span></span><span><span><span><span> could be appropriate for controlling mosquito population particularly in areas experiencing high insecticide resistance or outdoor biting mosquitoes.</span></span></span></span>展开更多
Mosquitoes are an interesting topic due to their medical importance, as they play an active role in the transmission of many pathogens and parasites, acting as vectors for various pathologies that are deadly to humans...Mosquitoes are an interesting topic due to their medical importance, as they play an active role in the transmission of many pathogens and parasites, acting as vectors for various pathologies that are deadly to humans, such as dengue, yellow fever, chikungunya, West Nile virus, encephalitis and malaria, among many others that are less common. In terms of morbidity and mortality caused by vector-borne diseases, mosquitoes are the most dangerous animals for humanity and, although they also play a role in the ecosystem as a food source for other organisms, their importance for public health cannot be overlooked. As highly efficient vectors, they put more than three billion people at risk, mainly in tropical and subtropical regions as well as in Europe, since heat waves and flooding are becoming more frequent and severe, and summers are getting longer and warmer, accelerating mosquito development, biting rates, and the incubation of the pathogens within their bodies. Female mosquitoes bite to acquire proteins for the development of their ovaries and eggs and, in the process, acquire pathogens and/or parasites from one vertebrate host and transmit them to another, usually after a short period of replication. Three of their four life stages are lived in still freshwater, so it is crucial to understand their range of action when they reach adulthood and leave the water, in order to plan and implement local prevention measures. A set of georeferenced abundance data collected in mainland Portugal over seven years was linked to cartographed water bodies in a geographic information system to estimate the distances at which Culex pipiens s.l. had a significant presence, with criteria based on the size of the catches. The result allows for an estimate of the fly range of those mosquitoes, which can be used to focus countermeasures.展开更多
In this paper Clematis sect. Aspidanthera s.l. is revised. Seventy_ two species and 15 varieties are recognized. They are keyed, described, and in most cases illustrated, and are classified into six subsections. Of th...In this paper Clematis sect. Aspidanthera s.l. is revised. Seventy_ two species and 15 varieties are recognized. They are keyed, described, and in most cases illustrated, and are classified into six subsections. Of them, on e series, five species, and two varieties are described as new, and two new rank s are proposed. Brief taxonomic history and geographical distribution of the sec tion are given, the evolutionary trends of several important morphological characters observed are e numerated, and the relationships of its subsections are discussed. As a resul t, subsect. Dioicae, which shows striking resemblance in both habit an d floral structure to sect. Clematis subsect. Clematis, is regar ded as t he primitive group, while subsect. Insidiosae, bearing pistillate flower wit h erect sepals and no staminodes, is regarded as the advanced group within the s ection.展开更多
基金supported by the Chinese National Natural Science Foundation (grants no.30625004,40771073 to HS)the Yunnan Natural Science Foundation (2008CC013 to HS)+4 种基金the US National Science Foundation (grant no. DEB-0321846,to DEB)the John D. and Catherine T. MacArthur Foundation (grant to JW,RR,and GM)the Innovation Project of the Chinese Academy of Sciences (KSCX2-YW-Z-030)a Mercer Fellowship from the Arnold Arboretum (to JPY)supported by the National Geographic Society (grant no.7405-03)
文摘The Hengduan Mountains region of south-west China is a noted biodiversity,hotspot, but the geographic origins and historical assembly of its rich endemic flora, including the sky-island species ofSolms-laubachia Muschl. （Brassicaceae）, have been little studied. Previous molecular studies on the phylogeny of Solms-laubachia showed it to be paraphyletic, leading to considerable expansion not only of its taxonomic limits, but also its geographic range, with the inclusion of taxa from outside the Hengduan region. However, these studies provided little resolution of interspecific relationships, preventing inferences about historical biogeography within the clade. In the present study, new sequence data from two nuclear genes （LEAFY and G3pdh） and two chloroplast intergenic spacers （petN-psbM and psbM-trnD） were combined with existing markers to increase phylogenetic signals. Phaeonychium villosum （Maxim.） Al-Shehbaz was found to be nested within Solms-laubachia s.l. In general, phylogenetic relationships appear to be a good predictor of geography, with the Hengduan Mountain endemics embedded in a paraphyletic grade of species from the western Himalayas and central Asia, but they also imply morphological homoplasy, lncongruence was detected between the nuclear and chloroplast gene trees, perhaps resulting from incomplete lineage sorting of ancestral polymorphisms. The crown age ofSolms-laubachia s.l. was estimated to be approximately 1.42-3.68 mya, using Bayesian relaxed molecular clock analysis. Historical biogeographic analysis using a parametric dispersalextinction-cladogenesis model inferred central Asia and the western Himalayas as most probable ancestral range of Solms-laubachia s.l., and estimated higher rates of eastward expansion than westward during the diversification of descendant lineages. In summary, our results suggest that Solms-laubachia s.l. originated during the Pliocene in central Asia, and subsequently migrated eastward into the Hengduan Mountains, colonizing sky-island, alpine scree-slope habitats that may have provided novel ecological opportunity and accelerated speciation, ultimately establishing this region as the present center of diversity of the genus.
基金This work was produced by the US National Institute of Health/Fogarty International Center under SR01TW008508.
文摘The standard methods for regression analyses of clustered riverine larval habitat data of Simulium damnosum s.l.a major black-fly vector of onchoceriasis,postulate models relating observational ecological-sampled parameter estimators to prolific habitats without accounting for residual intra-cluster error correlation effects.Generally,this correlation comes from two sources:(1)the design of the random effects and their assumed covariance from the multiple levels within the regression model and(2)the correlation structure of the residuals.Unfortunately,inconspicuous errors in residual intracluster correlation estimates can overstate precision in forecasted S.damnosum s.l.riverine larval habitat explanatory attributes regardless how they are treated(e.g.independent,autoregressive,Toeplitz,etc.).In this research,the geographical locations for multiple riverine-based S.damnosum s.l.larval ecosystem habitats sampled from two preestablished epidemiological sites in Togo were identified and recorded from July 2009 to June 2010.Initially,the data were aggregated into PROC GENMOD.An agglomerative hierarchical residual cluster-based analysis was then performed.The sampled clustered study site data was then analyzed for statistical correlations using monthly biting rates(MBR).Euclidean distance measurements and terrain-related geomorphological statistics were then generated in ArcGIS.A digital overlay was then performed also in ArcGIS using the georeferenced ground coordinates of high and low density clusters stratified by annual biting rates(ABR).The data was overlain onto multitemporal sub-meter pixel resolution satellite data(i.e.QuickBird 0.61m wavbands).Orthogonal spatial filter eigenvectors were then generated in SAS/Geographic Information Systems(GIS).Univariate and nonlinear regression-based models(i.e.logistic,Poisson,and negative binomial)were also employed to determine probability distributions and to identify statistically significant parameter estimators from the sampled data.Thereafter,Durbin–Watson statistics were used to test the null hypothesis that the regression residuals were not autocorrelated against the alternative that the residuals followed an autoregressive process in AUTOREG.Bayesian uncertainty matrices were also constructed employing normal priors for each of the sampled estimators in PROC MCMC.The residuals revealed both spatially structured and unstructured error effects in the high and low ABR-stratified clusters.The analyses also revealed that the estimators,levels of turbidity,and presence of rocks were statistically significant for the high-ABR-stratified clusters,while the estimators distance between habitats and floating vegetation were important for the low-ABR-stratified cluster.Varying and constant coefficient regression models,ABRstratified GIS-generated clusters,sub-meter resolution satellite imagery,a robust residual intra-cluster diagnostic test,MBR-based histograms,eigendecomposition spatial filter algorithms,and Bayesian matrices can enable accurate autoregressive estimation of latent uncertainity affects and other residual error probabilities(i.e.heteroskedasticity)for testing correlations between georeferenced S.damnosum s.l.riverine larval habitat estimators.The asymptotic distribution of the resulting residual adjusted intra-cluster predictor error autocovariate coefficients can thereafter be established while estimates of the asymptotic variance can lead to the construction of approximate confidence intervals for accurately targeting productive S.damnosum s.l.habitats based on spatiotemporal field-sampled count data.
基金the German Academic Exchange Service (DAAD)the Leibniz Institute of Plant Genetics and Crop Research (IPK),Germany
文摘A molecular phylogenetic analysis of the genus Corchorus(Grewioideae,Malvaceae s.l.)is presented,based on sequences of the nuclear ribosomal DNA internal transcribed spacer(ITS)region for 144 accessions representing 47 species.Several other genera from the subfamily Grewioideae,namely Pseudocorchorus,Triumfetta,Sparrmannia,Entelea,and Grewia,were included as outgroups.The monophyly of the genus was well supported by all phylogenetic analyses(maximum likelihood,Bayesian approaches,and parsimony),and Corchorus was divided into four major clades.The majority of African species formed a statistically highly supported and distinct clade separated from the other pantropically distributed species.Several endemic species from Australia,New Caledonia,and tropical America were nested within this distinct clade,indicating dispersal from Africa to the rest of the pantropics.Based on the taxa included in this study,the two cultivated species(C.olitorius and C.capsularis)shared a common ancestry with wild species of C.africanus,C.brevicornatus,C.pseudocapsularis,C.pseudo-olitorius,C.urticifolius,C.pilosus,C.orinocensis,and C.cunninghamii.Pseudocorchorus,previously considered an accepted genus,was nested within the genus Corchorus and shared a common ancestry especially with C.depressus and C.siliquosus.Based on morphological and anatomical similarity as well as the results of the present molecular findings,inclusion of the six Pseudocorchorus species into Corchorus is proposed,with Pseudocorchorus as a synonym of Corchorus.Of the included outgroup taxa,Triumfetta is the closest sister to Corchorus,while the common ancestor of Corchorus/Pseudocorchorus,Triumfetta,Sparrmannia,and Entelea is Grewia.A further phylogenetic study with more taxa mainly from Australia,together with additional molecular markers and morphological investigation,would help to test the hypothesis on the biogeography and growth form evolution of the genus Corchorus.
文摘Using a geographic information system (GIS), the relations between a georeferenced data set of Culex pipiens s.l. collected in Portugal mainland during seven years (2006-2012) and meteorological and physiographic parameters are evaluated. This work is one of the results of a long-term surveillance program of pernicious insects that act as vectors of various diseases;its focus is on the possibility of prevention that can be achieved with abundance data. The focus on Culex pipiens is justified by its abundance and its competence as a vector for numerous health issues. The cumulative distribution of monthly captures by each meteorological parameter allows to compute thresholds corresponding to mosquito massive presence related to 90% of the captures. Using the weather parameters measured in the network of weather stations across the country, a monthly average of each parameter of interest (temperature, humidity, etc.) is computed and an interpolation of the results is made to produce raster maps corresponding to each month. The previously obtained thresholds are applied to each map, producing spatial masks with the relevant zones for each parameter. The intersection of the various masks for each month shows the most densely populated area of Culex, and the ensemble allows us to observe the evolution of mosquito presence through the critical season, which is from May to October at these latitudes. In parallel, mosquito abundance data are related to physiographic parameters. The relative distribution of female mosquitoes across land cover types in each month allows identifying which classes and seasons are most relevant. Orthometric altitude related to the presence of 90% of the catches shows the limits reached by mosquitoes in each month. The results are applied to the previously obtained climate envelopes, delimiting critical areas where the level of risk of transmission of the pathogens for which Culex pipiens is a competent vector is high and countermeasures should be concentrated, allowing its planning, and targeting on a monthly basis. The described procedure can be used with other relevant vectors in any region of the world, whenever abundance data is available.
文摘<strong>Background: </strong><span><span><span><span>With the rapid expansion of insecticide resistance limiting the effectiveness of insecticide-based vector control interventions, integrated control strategies associating larviciding could be appropriate to improve current control efforts. The present experimental study assesses laboratory and field efficacy of the larvicide </span></span></span></span><span><span><span><span>VectoMax</span></span></span></span><span><span><span><span style="color:#111111;font-family:Roboto, sans-serif;font-size:16px;white-space:normal;background-color:#FFFFFF;"><sup>®</sup></span></span></span></span><span><span><span><span>G</span></span></span></span><span><span><span><span> on <i>Anopheline</i> and <i>Culicine</i> larval stages in Yaoundé. <strong>Methods:</strong> The effect of the larvicide </span></span></span></span><span><span><span><span>VectoMax</span></span></span></span><span><span><span><span style="color:#111111;font-family:Roboto, sans-serif;font-size:16px;white-space:normal;background-color:#FFFFFF;"><sup>®</sup></span></span></span></span><span><span><span><span>G,</span></span></span></span><span><span><span><span> a combination of <i>Bacillus</i><span> <i>thuringiensis</i> var. <i>israelensis</i> </span>(<i>Bti</i>) </span></span></span></span><span><span><span><span>and <i>Bacillus</i> <i>sphaericus</i> (<i>Bs</i>),</span></span></span></span><span><span><span><span> on larval development was assessed during both laboratory and open field trial experiments. Laboratory experiments permitted the evaluation of five different concentrations with four replicates/experiments. Laboratory experiments were conducted with <i>Anopheles</i> <i>coluzzii</i> “Ngousso” and <i>Culex</i> <i>quinquefasciatus</i> laboratory strains. Open field trials were conducted using </span></span></span></span><span><span><span><span>sixteen plastic containers with a diameter of 0.31 m buried in an array of four rows with 4 containers each. Distance between rows and between containers in a row was 1 meter. This experiment permitted to </span></span></span></span><span><span><span><span>test the effect of the microbial larvicide </span></span></span></span><span><span><span><span>VectoMax</span></span></span></span><span><span><span><span style="color:#111111;font-family:Roboto, sans-serif;font-size:16px;white-space:normal;background-color:#FFFFFF;"><sup>®</sup></span></span></span></span><span><span><span><span>G</span></span></span></span><span><span><span><span> under operational application conditions on field mosquito populations. <strong>Results:</strong> <span>The time to induce 100% mortality after exposure to serial concentrations of the larvicide varied according to the dose from 4 - 12 hours for <i>An.</i> <i>coluzzii</i> and 6 - 9 hours for <i>Cx.</i> <i>quinquefasciatus</i> in laboratory experiments. Measurements of the</span> residual activity indicated that all </span></span></span></span><span><span><span><span>VectoMax</span></span></span></span><span><span><span><span style="color:#111111;font-family:Roboto, sans-serif;font-size:16px;white-space:normal;background-color:#FFFFFF;"><sup>®</sup></span></span></span></span><span><span><span><span>G</span></span></span></span><span><span><span><span> concentrations were still active after 35 days and killed 86</span></span></span></span><span><span><span><span>% </span></span></span></span><span><span><span><span>-</span></span></span></span><span><span><span><span> </span></span></span></span><span><span><span><span>100% of larvae. Lethal dose of </span></span></span></span><span><span><span><span>VectoMax</span></span></span></span><span><span><span><span style="color:#111111;font-family:Roboto, sans-serif;font-size:16px;white-space:normal;background-color:#FFFFFF;"><sup>®</sup></span></span></span></span><span><span><span><span>G</span></span></span></span><span><span><span><span> killing 50% of larvae was estimated at 5.24 × 10<sup>-8</sup> mg/m<sup>2</sup> for <i>An.</i> <i>coluzzii</i> and 1.25 × 10<sup>-8</sup> mg/m<sup>2</sup> for <i>Cx.</i> <i>quinquefasciatus</i>. The lethal concentration inducing 95% mortality was estimated at 3.13 × 10<sup>-7</sup> mg/m<sup>2</sup> for <i>An.</i> <i>coluzzii</i> and 2.5 × 10<sup>-8</sup> <span>mg/m<sup>2</sup> for <i>Cx.</i> <i>quinquefasciatus</i>. Open field trials tests indicated that </span>sub-lethal concentrations of </span></span></span></span><span><span><span><span>VectoMax</span></span></span></span><span><span><span><span style="color:#111111;font-family:Roboto, sans-serif;font-size:16px;white-space:normal;background-color:#FFFFFF;"><sup>®</sup></span></span></span></span><span><span><span><span>G</span></span></span></span><span><span><span><span> successfully killed 100% <i>An.</i> <i>gambiae</i> s.l. larvae within 24 hours, while with <i>Culex</i> spp. larvae, 100% mortality was recorded after 48 hours post-treatment. Natural recolonization of water containers by larvae was recorded between 3 and 6 days respectively after the treatment with sublethal doses. Late instar larvae were recorded 5 and 6 days after treatment. When the jars were treated with reference dosage or supra doses of </span></span></span></span><span><span><span><span>VectoMax</span></span></span></span><span><span><span><span style="color:#111111;font-family:Roboto, sans-serif;font-size:16px;white-space:normal;background-color:#FFFFFF;"><sup>®</sup></span></span></span></span><span><span><span><span>G,</span></span></span></span><span><span><span><span> recolonization of water containers was observed six days after treatments. No pupae of both species were found 6 and 7 days post-treatment. <strong>Conclusions:</strong> The study indicated high efficacy of the microbial larvicide </span></span></span></span><span><span><span><span>VectoMax</span></span></span></span><span><span><span><span style="color:#111111;font-family:Roboto, sans-serif;font-size:16px;white-space:normal;background-color:#FFFFFF;"><sup>®</sup></span></span></span></span><span><span><span><span>G</span></span></span></span><span><span><span><span> against <i>Anopheline</i> and <i>Culex</i> larvae. Microbial larvicides such as </span></span></span></span><span><span><span><span>VectoMax</span></span></span></span><span><span><span><span style="color:#111111;font-family:Roboto, sans-serif;font-size:16px;white-space:normal;background-color:#FFFFFF;"><sup>®</sup></span></span></span></span><span><span><span><span>G</span></span></span></span><span><span><span><span> could be appropriate for controlling mosquito population particularly in areas experiencing high insecticide resistance or outdoor biting mosquitoes.</span></span></span></span>
文摘Mosquitoes are an interesting topic due to their medical importance, as they play an active role in the transmission of many pathogens and parasites, acting as vectors for various pathologies that are deadly to humans, such as dengue, yellow fever, chikungunya, West Nile virus, encephalitis and malaria, among many others that are less common. In terms of morbidity and mortality caused by vector-borne diseases, mosquitoes are the most dangerous animals for humanity and, although they also play a role in the ecosystem as a food source for other organisms, their importance for public health cannot be overlooked. As highly efficient vectors, they put more than three billion people at risk, mainly in tropical and subtropical regions as well as in Europe, since heat waves and flooding are becoming more frequent and severe, and summers are getting longer and warmer, accelerating mosquito development, biting rates, and the incubation of the pathogens within their bodies. Female mosquitoes bite to acquire proteins for the development of their ovaries and eggs and, in the process, acquire pathogens and/or parasites from one vertebrate host and transmit them to another, usually after a short period of replication. Three of their four life stages are lived in still freshwater, so it is crucial to understand their range of action when they reach adulthood and leave the water, in order to plan and implement local prevention measures. A set of georeferenced abundance data collected in mainland Portugal over seven years was linked to cartographed water bodies in a geographic information system to estimate the distances at which Culex pipiens s.l. had a significant presence, with criteria based on the size of the catches. The result allows for an estimate of the fly range of those mosquitoes, which can be used to focus countermeasures.
文摘In this paper Clematis sect. Aspidanthera s.l. is revised. Seventy_ two species and 15 varieties are recognized. They are keyed, described, and in most cases illustrated, and are classified into six subsections. Of them, on e series, five species, and two varieties are described as new, and two new rank s are proposed. Brief taxonomic history and geographical distribution of the sec tion are given, the evolutionary trends of several important morphological characters observed are e numerated, and the relationships of its subsections are discussed. As a resul t, subsect. Dioicae, which shows striking resemblance in both habit an d floral structure to sect. Clematis subsect. Clematis, is regar ded as t he primitive group, while subsect. Insidiosae, bearing pistillate flower wit h erect sepals and no staminodes, is regarded as the advanced group within the s ection.
