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71.
In Burkina Faso, we assessed the efficacy of treating cattle with a footbath containing aqueous formulations of pyrethroids to control two tsetse-fly species, Glossina tachinoides Westwood, 1850 (Diptera, Glossinidae) and Glossina palpalis gambiensis Vanderplank 1949. Legs were the most targeted parts of the body for tsetse-fly blood meals: 81% (95% CI: 73, 89) for G. tachinoides and 88% (81, 95) for G. palpalis.

The in-stable efficacy of footbath treatments was compared with manual full spraying with a 0.005% alphacypermethrin (Dominex, FMC, Philadelphia, USA) formulation (250 mL versus 2 L). The proportions of knocked-down flies were the same with footbath and full spray but the latter was more protective against fly bites. In field use, the efficacy of both methods should be similar given the recommended treatment frequency: 3 days for footbath versus 7 days for full spray.

Among 96 cattle drinking at the same water point in Dafinso (Burkina Faso), 68 (71%) were treated with a footbath containing a 0.005% deltamethrin formulation (Vectocid, CEVA SA, Libourne, France). We observed the effect of this live-bait technique on the one hand on released cohorts of reared, irradiated flies, and on the other hand on wild tsetse flies. In both cases, the footbath treatment was associated with a reduction of the apparent fly density probably related to an increased mortality.  相似文献   

72.

BACKGROUND

Aerial treatments for invasive species management are now common, but we are unaware of any work published in the scientific literature quantifying how the interplay of numerous factors affects flight time and therefore operational costs. Here, we analyse aerial treatment data collected from two ant-eradication programmes, quantifying how the relationships between flight time and area are influenced by numerous aircraft/delivery system/bait/flight speed combinations.

RESULTS

For bait dispersal by helicopters, and when swath widths are equivalent, side-mounted Isolair was significantly more efficient than the simultaneous use of two underslung buckets, and use of two buckets was slightly but not significantly more efficient than one bucket. In this scenario, delivery by Isolair was, on average, 39.8% and 31.5% more efficient than the use of one or two buckets, respectively. However, when the swath width used with Isolair was halved to 10 m and flight speed was increased slightly, flight time was significantly greater compared to the other configurations. For bait dispersed by drone, flights conducted using an upgraded Flight Management System (FMS) and greater flight speed but smaller swath width were significantly more efficient than flights using the older FMS and lower flight speed. Over 10 and 50 ha the helicopter was 2.87 and 4.82 times more time efficient than the drone.

CONCLUSION

We encourage practitioners to publish data from their aerial treatments, and to try new methods, to accelerate improvements in efficiency and reduce the costs of aerial treatments. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.  相似文献   
73.
Hydrolysis and Condensation of Silane Agent for Metallic Surface Treatment   总被引:1,自引:0,他引:1  
Novel surface treatment technique by silane film is developing for metallic anti corrosion and coat improvement. The key points, hydrolysis and condensation, for the stability of the Silane agent(SA) solution is investigated, and the effective factors of stability for silane agent solution and the relative rule are discussed. It is found that stability of SA solution is related to the temperature, pH, solvents, SA concentration and additive by studying the state of the solution and the conductivity-time curve of SA solution. Meanwhile, controlling factors and improving methods for SA stability are proposed to guide the practical application of metallic surface anti-corrosion treatment by SA.  相似文献   
74.
There are several methods to cope with the common problem of the uneven subsidence of foundation. The reason for uneven settlement of foundation of the frame structure was analyzed in this paper. Considering the limitation of the construction site and the principle of consolidation, a feasible reinforcement measure was taken. Meanwhile, a practical construction pattern was chosen upon the comparison of the reinforcement technology analysis and the construction method. The observation of the settlement result after consolidation of the structure shows that the result of this reinforcement treatment pattern is effective.  相似文献   
75.
With the development of the economy, the demand forhabitation is enhanced and the sewage and industrial waster water must be disposed before outlet. Today, most of the sewage treatment plants are built on the aboveground without discussing the underground. Therefore, by the comparative analysis of the property and cost of the underground sewage treatment plant and the ground, the underground sewage treatment plant have merits in save the city land and improvement environment.The Chongqing citypossess a lot of advantages in using the space of underground with the analysis of the physiognomy and geology condition of the Chongqing city. Therefore, the development of underground sewage treatment plant is feasible in the Chongqing city.  相似文献   
76.
Flowing dynamic characteristics and its temperature dynamic characteristics of a three-level sewage pipe network in Chongqing were analyzed. A mall's building whole year load was simulated. In the adverse condition of wastewater flow, the market construction peak discharge heat was compared with the sewage heat load, the balance between the most adverse flow and the building demand was found. Explored supply and demand matching method between urban sewage and city building load in flow adverse condition to take full advantage of the urban sewage cold and hot resources. the composite system was adeptcd to make up the most unfavorable flow time of sewage average heat load and the construction load difference; it also puts forward principle of load sharing and control strategy aimed at compound system.  相似文献   
77.
Based on introducing fieldbus and fieldbus control system, in this paper, a distributed monitoring system for city wastewater treatment network based on LonWorks is given, the construction, function and character of this network are analyzed.  相似文献   
78.
79.
光皮桦超干种子回湿方法研究   总被引:3,自引:0,他引:3  
方莹  周坚 《种子》2007,26(2):36-38
超干处理的光皮桦种子直接吸胀会引起种子活力下降,回湿处理可以减轻吸胀过程所造成的损伤.本试验以超干储藏1年的光皮桦种子,分别经回湿处理中湿度、温度和时间三因素组合的30种预先回湿处理.结果表明:湿度、温度和时间三因素是回湿处理的主要因素;30种处理中有6种处理的发芽率、发芽指数和高于对照,以30℃60%RH回湿4 d显著高于对照,效果最佳.  相似文献   
80.
硝酸钙在底泥修复中的作用机理及   总被引:11,自引:0,他引:11  
受污染底泥的修复已经成为水环境修复中的重要组成部分,在底泥中注入硝酸钙则是近十多年来发展起来的一种污染底泥原位处理技术。全面分析了硝酸钙在底泥修复中去除有机物、抑制磷的释放以及消除水体黑臭现象的机理,并介绍了这一技术在国内外的研究和应用状况。研究成果表明:在底泥中注入硝酸钙的技术已从实验室和中试研究阶段发展到了实际的工程动作阶段,并且在有机物PAHS的降解和硫化物的去除方面已经得到了很好的效果。  相似文献   
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