scholarly journals Control effectiveness of APL formulation against dengue- and Zika-transmitting Aedes mosquitoes in Gia Lai province, Vietnam

2021 ◽  
Author(s):  
Phung Thi Kim Hue ◽  
Le Tri Vien ◽  
Dau Minh Nga ◽  
Le Van Truong ◽  
Hoang Ha ◽  
...  
Keyword(s):  
Mosquito Control ◽  
Mosquito Species ◽  
Larval Density ◽  
Ethanol Extract ◽  
Egg Hatching ◽  
Control Effectiveness ◽  
Cashew Nut ◽  
Aedes Mosquitoes ◽  
Cashew Nut Shell ◽  
Lime Peel

Background: Dengue fever and Zika are two of the Aedes-borne diseases. Despite being widely used, synthetic mosquitocides become abortive for the mosquito control due to growing resistance and environmental pollution. In Gia Lai province (dengue-endemic area), a huge amount of cashew nut shell waste with roughly 100,000 tons/year has been disposed of into the environment, potentiating a high risk of pollution. Methodology/Principal findings: To utilize it, anacardic acid was extracted and combined it with ethanol extract of the local lime peel, which contains limonene, to generate APL formulation. APL robustly exhibited inhibition of egg hatching, larvicidal effect, and repellent effect against female mosquitoes from oviposition sites in the laboratory and field. The results showed that, at a dose of 12.5 ppm, the APL formulation after 24 hours of treatment demonstrated oviposition deterrence against Ae. aegypti (43.6%) and Ae. albopictus (59.6%); inhibited egg hatching of Ae. aegypti (49.6%) and Ae. albopictus (59.6%); caused larval lethality in Ae. aegypti (LC 50 = 9.5 ppm, LC 90 = 21 ppm) and Ae. albopictus (LC 50 = 7.6 ppm, LC 90 = 18 ppm). Under natural field conditions, it showed a 100% reduction in larval density after 48 and 72 hours of the APL treatment at a tested concentration of 120 mg a.i./m 2 and maintained a mortality rate of 100% in the next 14 days. Conclusions/Significance: The APL formulation is promisingly to become an environmentally friendly and highly effective biological product for future management programs of dengue and Zika-transmitting vectors. Here offer prospects in controlling critical illnesses transmitted by several mosquito species in dengue-endemic areas.

Larvicidal Properties of Citrus hystrix DC Fruit (Taw-Shaut-Khar-Thee) Extracts against Aedes aegypti Larvae Collected from Different Townships of Yangon

2019 ◽  
Vol 31 (1) ◽  
pp. 23-29
Keyword(s):  
Mosquito Control ◽  
Ethanol Extract ◽  
Botanical Insecticides ◽  
Fruit Extract ◽  
Aedes Mosquitoes ◽  
Ethanol Extracts ◽  
Dry Fruit ◽  
Peel Extract ◽  
Lc50 And Lc90

The present study aimed to evaluate the larvicidal and ovicidal activities of ethanol extracts of dried fruits, internal fruit materials and peels of Citrus hystrix DC against Aedes aegtpti larvae from Dagon (North) and Hlinethaya Townships in Yangon Region from May 20l5 to December 2016. The 3rd and 4th stage larvae were exposed for 24 hours to various concentrations of ethanol extracts of different parts of the Citrus hystrix fruit. The dry fruit extract resulted in significantly higher mortality of 100% and 96.4% in Aedes larvae collected from Dagon (North) and Hlinethaya, respectively (P<0.05). The mortality of Aedes larvae in peel extract was found to be 92.5% in Hlinethaya and 94.4% in Dagon (North), respectively. The extract of Citrus hystrix DC fruit was very effective to kill Aedes larvae collected from Dagon (North). When compared with each other, slightly higher mortality of larvae from Dagon (North) was observed at 0.l5 g/100 m1 concentration of all extracts than that of larvae from Hlinethaya. Ovicidal test found 100% protection to lay their eggs at 0.0l25 g/l00 ml dose and persistency test found 100% mortality of 3rd and 4th instar Aedes larvae up to 6 days at a dose of 0.2 g/100 ml fruit extract. The LC50 and LC90 values of 0.0343 g, 0.0415 g, 0.0231 g, and 0.1256 g, 0.1584 g, 0.0742 g for peel, internal material and fruit extracts, respectively, on Aedes larvae from Dagon were found to be lower than 0.0396 g, 0.0552 g, 0.0280 g and 0.1408 g, 0.2322 g, 0.1060 g, respectively, from Hlinethaya. The findings of the present study revealed that the ethanol extract of the fruit of Citrus hystrix DC has strong larvicidal, ovicidal and long-term persistency activity on Aedes mosquitoes as a good source of preparations for mosquito control. The study may contribute to a reduction in the application of synthetic insecticides, which in turnincreases the opportunity for natural control of various medically important insects by botanical insecticides.

scholarly journals Modeling the effects of Aedes aegypti's larval environment on adult body mass at emergence

2021 ◽  
Author(s):  
Melody Walker ◽  
Karthikeyan Chandrasegaran ◽  
Clement Vinauger ◽  
Michael Robert ◽  
Lauren M. Childs
Keyword(s):  
Body Mass ◽  
Mosquito Species ◽  
Larval Density ◽  
Information Criterion ◽  
The Body ◽  
Control Measures ◽  
Model Complexity ◽  
Adult Body Mass ◽  
Aedes Mosquitoes ◽  
The Impact

Mosquitoes vector harmful pathogens that infect  millions  of people every year, and developing approaches to effectively control mosquitoes is a topic of great interest. However, the success of many control measures is highly dependent upon ecological, physiological, and life history traits of the mosquito species. The behavior of mosquitoes and their potential to vector pathogens can also be impacted by these traits. One trait of interest is mosquito body mass, which depends upon many factors associated with the environment in which juvenile mosquitoes develop. Our experiments examined the impact of larval density on the body mass of Aedes aegypti  mosquitoes, which are important vectors of dengue, Zika, yellow fever, and other pathogens. To investigate the interactions between the larval environment and mosquito body mass, we built a discrete time  mathematical model that incorporates body mass, larval density, and food availability and fit the model to our experimental data. We considered three categories of model complexity informed by data, and selected the best model within each category using Akaike's Information Criterion. We found that the larval environment is an important determinant of the body mass of mosquitoes upon emergence. Furthermore, we found that larval density has greater impact on body mass of adults at emergence than on development time, and that inclusion of density dependence in the survival of female aquatic stages in models is important.  We discuss the implications of our results for the control of Aedes  mosquitoes and on their potential to spread disease.

A Simple PCR Assay for Discrimination of Dengue Vectors from Nsukka LGA, Nigeria

2020 ◽  
Vol 10 (1) ◽  
pp. 67-77
Author(s):  
Amos Watentena ◽  
Ikem Chris Okoye ◽  
Ikechukwu Eugene Onah ◽  
Onwude Cosmas Ogbonnaya ◽  
Emmanuel Ogudu
Keyword(s):  
Aedes Aegypti ◽  
Aedes Albopictus ◽  
Mosquito Species ◽  
Public Health Problem ◽  
Major Public Health Problem ◽  
Mosquito Vector ◽  
Aedes Mosquitoes ◽  
Allele Specific ◽  
Arboviral Diseases ◽  
Dengue Vectors

Mosquitoes of Aedes species are vectors of several arboviral diseases which continue to be a major public health problem in Nigeria. This study among other things, morphologically identified Aedes mosquitoes collected from Nsukka LGA and used an allele specific PCR amplification for discrimination of dengue vectors. Larval sampling, BG-sentinel traps and modified human landing catches were used for mosquito sampling in two selected autonomous communities of Nsukka LGA (Nsukka and Obimo). A total of 124 Aedes mosquitoes consisting of five (5) different species were collected from April to June, 2019 in a cross-sectional study that covered 126 households, under 76 distinct geographical coordinates. Larvae was mainly collected from plastic containers 73% (n=224), metallic containers 14% (n=43), earthen pots 9% (n=29) and used car tyres 3% (n=9), reared to adult stage 69.35% (n=86), and all mosquitoes were identified using standard morphological keys. Five (5) Aedes mosquito species were captured; Aedes aegypti 83(66.94%), Aedes albopictus 33(26.61%), Aedes simpsoni (4.48%), Aedes luteocephalus (≤1%) and Aedes vittatus (≤1%). Nsukka autonomous community had higher species diversity than Obimo. Allele specific amplification confirmed dengue vectors, Aedes aegypti and Aedes albopictus species on a 2% agarose gel. Since the most recent re-emergence of arboviral diseases is closely associated with Aedes species, findings of this study, therefore, give further evidence about the presence of potential arboviral vectors in Nigeria and describe the role of a simple PCR in discriminating some. Further entomological studies should integrate PCR assays in mosquito vector surveillance.

scholarly journals Application of a cashew-based oxime in extracting Ni, Mn and Co from aqueous solution

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Chi M. Phan ◽  
Son A. Hoang ◽  
Son H. Vu ◽  
Hoang M. Nguyen ◽  
Cuong V. Nguyen ◽  
...  
Keyword(s):  
Organic Phase ◽  
Extraction Efficiency ◽  
Acidic Solution ◽  
Lithium Ion ◽  
Metal Extraction ◽  
Economic Potential ◽  
Cashew Nut ◽  
Valuable Metals ◽  
Loaded Organic Phase ◽  
Cashew Nut Shell

Abstract Background Cashew nut shell is a by-product of cashew (Anacardium occidentale) production, which is abundant in many developing countries. Cashew nut shell liquor (CNSL) contains a functional chemical, cardanol, which can be converted into a hydroxyoxime. The hydroxyoximes are expensive reagents for metal extraction. Methods CNSL-based oxime was synthesized and used to extract Ni, Co, and Mn from aqueous solutions. The extraction potential was compared against a commercial extractant (LIX 860N). Results All metals were successfully extracted with pH0.5 between 4 and 6. The loaded organic phase was subsequently stripped with an acidic solution. The extraction efficiency and pH0.5 of the CNSL-based extractant were similar to a commercial phenol-oxime extractant. The metals were stripped from the loaded organic phase with a recovery rate of 95% at a pH of 1. Conclusions Cashew-based cardanol can be used to economically produce an oxime in a simple process. The naturally-based oxime has the economic potential to sustainably recover valuable metals from spent lithium-ion batteries. Graphic abstract

Particleboard from Cashew Nut Shell Liquid

2007 ◽  
Vol 15 (1) ◽  
pp. 75-82 ◽  
Author(s):  
Lubi C. Mary ◽  
Eby Thomas Thachil
Keyword(s):  
Cashew Nut Shell Liquid ◽  
Cashew Nut ◽  
Cashew Nut Shell

scholarly journals At the tip of an iceberg: citizen science and active surveillance collaborating to broaden the known distribution of Aedes japonicus in Spain

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Roger Eritja ◽  
Sarah Delacour-Estrella ◽  
Ignacio Ruiz-Arrondo ◽  
Mikel A. González ◽  
Carlos Barceló ◽  
...  
Keyword(s):  
Citizen Science ◽  
Active Surveillance ◽  
Mosquito Control ◽  
Mosquito Species ◽  
Surveillance Systems ◽  
Northern Spain ◽  
Surveillance Strategy ◽  
Aedes Japonicus ◽  
Invasive Mosquito Species ◽  
Invasive Mosquito

Abstract Background Active surveillance aimed at the early detection of invasive mosquito species is usually focused on seaports and airports as points of entry, and along road networks as dispersion paths. In a number of cases, however, the first detections of colonizing populations are made by citizens, either because the species has already moved beyond the implemented active surveillance sites or because there is no surveillance in place. This was the case of the first detection in 2018 of the Asian bush mosquito, Aedes japonicus, in Asturias (northern Spain) by the citizen science platform Mosquito Alert. Methods The collaboration between Mosquito Alert, the Ministry of Health, local authorities and academic researchers resulted in a multi-source surveillance combining active field sampling with broader temporal and spatial citizen-sourced data, resulting in a more flexible and efficient surveillance strategy. Results Between 2018 and 2020, the joint efforts of administrative bodies, academic teams and citizen-sourced data led to the discovery of this species in northern regions of Spain such as Cantabria and the Basque Country. This raised the estimated area of occurrence of Ae. japonicus from < 900 km2 in 2018 to > 7000 km2 in 2020. Conclusions This population cluster is geographically isolated from any other population in Europe, which raises questions about its origin, path of introduction and dispersal means, while also highlighting the need to enhance surveillance systems by closely combining crowd-sourced surveillance with public health and mosquito control agencies’ efforts, from local to continental scales. This multi-actor approach for surveillance (either passive and active) shows high potential efficiency in the surveillance of other invasive mosquito species, and specifically the major vector Aedes aegypti which is already present in some parts of Europe. Graphical abstract

scholarly journals Mosquito Control Priorities in Florida—Survey Results from Florida Mosquito Control Districts

Pathogens ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 947
Author(s):  
Rishi Kondapaneni ◽  
Ashley N. Malcolm ◽  
Brian M. Vazquez ◽  
Eric Zeng ◽  
Tse-Yu Chen ◽  
...  
Keyword(s):  
State Government ◽  
Mosquito Control ◽  
Control Strategies ◽  
Mosquito Species ◽  
Research Priorities ◽  
Current Control ◽  
Control Programs ◽  
Common Control ◽  
Surveillance Programs ◽  
Research Questions

Florida lies within a subtropical region where the climate allows diverse mosquito species including invasive species to thrive year-round. As of 2021, there are currently 66 state-approved Florida Mosquito Control Districts, which are major stakeholders for Florida public universities engaged in mosquito research. Florida is one of the few states with extensive organized mosquito control programs. The Florida State Government and Florida Mosquito Control Districts have long histories of collaboration with research institutions. During fall 2020, we carried out a survey to collect baseline data on the current control priorities from Florida Mosquito Control Districts relating to (1) priority control species, (2) common adult and larval control methods, and (3) major research questions to address that will improve their control and surveillance programs. The survey data showed that a total of 17 distinct mosquito species were considered to be priority control targets, with many of these species being understudied. The most common control approaches included truck-mounted ultra-low-volume adulticiding and biopesticide-based larviciding. The districts held interest in diverse research questions, with many prioritizing studies on basic science questions to help develop evidence-based control strategies. Our data highlight the fact that mosquito control approaches and priorities differ greatly between districts and provide an important point of comparison for other regions investing in mosquito control, particularly those with similar ecological settings, and great diversity of potential mosquito vectors, such as in Florida. Our findings highlight a need for greater alignment of research priorities between mosquito control and mosquito research. In particular, we note a need to prioritize filling knowledge gaps relating to understudied mosquito species that have been implicated in arbovirus transmission.

Kinetic and structural changes during gasification of cashew nut shell char particles

2020 ◽  
Author(s):  
Hong Nam Nguyen ◽  
Duy Anh Khuong ◽  
Thi Thu Ha Vu ◽  
Thi Nga Mai ◽  
Toshiki Tsubota ◽  
...  
Keyword(s):  
Structural Changes ◽  
Cashew Nut ◽  
Cashew Nut Shell
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