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[Display omitted] • Beauveria bassiana JN5R1W1 with high virulence against adult mosquitoes was formulated. • Formulation was prepared in the form of an inverted emulsion using soybean oil. • Applying the inverted emulsion on a net was effective to control adult mosquitoes. In this study, an effective control agent and control technology for adult mosquitoes using entomopathogenic fungi is proposed as a solution to the adverse effects of chemical insecticides used for mosquito control. A formulation study was conducted using Beauveria bassiana JN5R1W1 with high virulence against both Aedes albopictus and Culex pipiens adult mosquitoes. For the inverted emulsion formulation, three kinds of vegetable oils were used to evaluate the germination promotion, UV blocking effects, and adhesion rate of conidia. As a result, soybean oil was selected as the most effective vegetable oil, and the corresponding formulation was made. Direct contact treatment of the inverted emulsion by spraying resulted in a mortality rate of approximately 100 % for both species of adult mosquitoes. However, in reality, since it is difficult to directly apply fungal agent treatment against adult mosquitoes, we evaluated a control method by indirect contact with mosquitoes after applying the inverted emulsion on a net. As an indirect treatment method, the prepared inverted emulsion showed a mortality rate of approximately 93 % or 89 % against Ae. albopictus and Cx. pipiens adult mosquitoes, respectively. Therefore, these results suggested that the inverted emulsion using B. bassiana JN5R1W1 is an effective control agent for controlling adult mosquitoes. [ABSTRACT FROM AUTHOR]

Oil and gas exploration and production in deep and ultra-deep wells located in high pressure and high temperature zones (HP/HT) are increasing considerably to meet global energy demands. Exploration in HP/HT zones presents several challenges to the performance of drilling fluids to maintain wellbore stability during the drilling process. The rheological characterization of drilling fluids has been extensively investigated through experiments at atmospheric pressure; however, there are many open questions concerning high-pressure conditions. This work aims to perform a rheological characterization of inverted emulsion drilling fluid with measurements performed under a wide high-pressure range. The experiments were carried out in a rheometer coupled to the pressure cell system. The results show that the impact of the pressure is more relevant in the solid than in the liquid-like regime. Not only the viscosity, storage modulus, and yield stress tend to increase under pressure but also the material yield strain. The higher the applied pressure, the greater is the deformation that the material withstands in the solid regime. These findings can bring relevant information to the oil and gas field since the knowledge of the material gel strength under high pressures is fundamental for the drilling operation. [Display omitted] • The viscosity of drilling fluid is near independent of pressure up to a certain pressure. • Pressure effects are significant in the gel strength than in the material viscosity. • The yield stress increased with the pressure applied to the material. • The higher pressure, the greater the deformation the fluid withstand before the yield point. [ABSTRACT FROM AUTHOR]

To isolate and formulate a native strain of Zoophthora radicans naturally infecting larvae of diamondback moth, Plutella xylostella, existing in South Australia and to provide evidence that formulation of the fungus is effective against P. xylostella larvae, and therefore, it could be used as a tool in pest management of this insect. Dose-response bioassays using formulated and unformulated forms of the fungus strain were carried out against third instar larvae of P. xylostella. Results obtained have indicated a significant increase in the larval mortality when higher concentrations of a formulated form of the fungus strain were applied compared to the treatments with the unformulated form (85·0 vs 57·5% of larval mortality, respectively, at the top concentration of 10 conidia/ml). The median lethal concentration (LC50) for a formulated form was 100 times less than that of the unformulated form when they were applied against the third instar larvae of P. xylostella. In addition, the formulation used in the present bioassays has preserved the viability of introduced fungus conidia for longer time in comparison with the unformulated conidia. The effective application of a formulated fungus strain against P. xylostella larvae constitutes the first step towards its use in pest management of this insect. The formulated fungus in inverted emulsion could be used as an alternative tool to insecticides in pest management of P. xylostella larvae because of the development of resistance to insecticides in the treated larvae. [ABSTRACT FROM AUTHOR]

In the field of bottom-up synthetic biology, lipid vesicles provide an important role in the construction of artificial cells. Giant unilamellar vesicles (GUVs), due to their membrane's similarity to natural biomembranes, have been widely used as cellular mimics. So far, several methods exist for the production of GUVs with the possibility to encapsulate biological macromolecules. The inverted emulsion-based method is one such technique, which has great potential for rapid production of GUVs with high encapsulation efficiencies for large biomolecules. However, the lack of understanding of various parameters that affect production yields has resulted in sparse adaptation within the membrane and bottom-up synthetic biology research communities. Here, we optimize various parameters of the inverted emulsion-based method to maximize the production of GUVs. We demonstrate that the density difference between the emulsion droplets, oil phase, and the outer aqueous phase plays a crucial role in vesicle formation. We also investigated the impact that centrifugation speed/time, lipid concentration, pH, temperature, and emulsion droplet volume has on vesicle yield and size. Compared to conventional electroformation, our preparation method was not found to significantly alter the membrane mechanical properties. Finally, we optimize the parameters to minimize the time from workbench to microscope and in this way open up the possibility of time-sensitive experiments. In conclusion, our findings will promote the usage of the inverted emulsion method for basic membrane biophysics studies as well as the development of GUVs for use as future artificial cells., (© 2019 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)