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Many species of devastating insect pests have acquired a high degree of resistance to insecticides in the field during the last few decades. Spodoptera exigua, for example, is the most damaging pests of economic crops with a worldwide spread. In a present study, the comparative growth, reproduction, and detoxification enzyme activity were evaluated along with exposure to three insecticides at low lethal doses of lufenuron, indoxacarb, and spinosad as compared to the control. Results indicate that the larval developmental time was significantly extended on lufenuron (21.5 ± 29 days) followed by indoxacarb (20.28 ± 0.24 days) and spinosad (19.74 ± 0.23 days) as compared to that on the control (18.13 ± 0.13 days). Similarly, the lowest number of eggs of S. exigua females were recorded on lufenuron (328.75 ± 50.81 eggs) followed by spinosad (367 ± 36.4 eggs) and indoxacarb (411.58 ± 42.38 eggs) as compared to that on the control (560.2 ± 13.47). Interestingly, the lowest intrinsic rate of increase (r) (0.121 ± 0.009) and highest mean generation time (T) (36.2 ± 0.35 days) were observed when larvae were treated to a low lethal concentration (LC

Bradysia odoriphaga is a major insect pest that infests Chinese chive in northern China. Clothianidin is a second-generation neonicotinoid insecticide that is commonly used against B. odoriphaga. In this study, the effect of sublethal clothianidin concentrations (LC5 and LC10) on key biological characteristics of B. odoriphaga was investigated using an age-stage, two-sex life table method. Bioassays results showed that clothianidin exhibited high toxicity against B. odoriphaga with LC50 of 1.898 mg L−1 following 24 h exposure. The developmental duration of larvae was significantly increased when exposed to the LC5 (0.209 mg L−1) and LC10 (0.340 mg L−1) of clothianidin. No significant effects were observed on the pupal stage, adult pre-oviposition period (APOP), total pre-oviposition period (TPOP), and mean longevities of male and female. The oviposition period and fecundity of B. odoriphaga were reduced in clothianidin-treated groups. Moreover, key demographic parameters, including the intrinsic rate of increase (r), finite rate of increase (λ), and net reproductive rate (R0), were significantly decreased by the LC5 and LC10 of clothianidin, while no effects were noted on mean generation time (T). Overall, this study showed that sublethal concentrations of clothianidin have a detrimental effect on B. odoriphaga developmental period, fecundity, and life table parameters. Therefore, clothianidin has the potential to suppress the population of B. odoriphaga even at sublethal concentrations.

The nanofluid flows play a vital role in many engineering processes owing to their notable industrial usage and excessive heat transfer abilities. Lately, an advanced form of nanofluids namely “hybrid nanofluids” has swapped the usual nanofluid flows to further augment the heat transfer capabilities. The objective of this envisaged model is to compare the performance of two renowned hybrid nanofluid models namely Hamilton–Crosser and Yamada–Ota. The hybrid nanoliquid (TiO2-SiC/DO) flow model is comprised of Titanium oxide (TiO2) and Silicon carbide (SiC) nanoparticles submerged into Diathermic oil (DO). The subject flow is considered over a stretched surface and is influenced by the magnetic dipole. The uniqueness of the fluid model is augmented by considering the modified Fourier law instead of the traditional Fourier law and slip conditions at the boundary. By applying the suitable similarity transformations, the system of ordinary differential equations obtained from the leading partial differential equations is handled by the MATLAB solver bvp4c package to determine the numerical solution. It is divulged that the Yamada–Ota model performs considerably better than the Hamilton–Crosser flow model as far as heat transfer capabilities are concerned. Further, the velocity reduces on increasing hydrodynamic interaction and slip parameters. It is also noted that both temperature profiles increase for higher hydrodynamic interaction and viscous dissipation parameters. The envisioned model is authenticated when compared with an already published result in a limiting case.

The present study analyzes the comparison of the Xue and Yamada-Ota models for a hybrid nanoliquid flow in porous media occurring amidst a rotating channel with surface catalyzed reaction. Here, the hybrid nanofluid flow is studied under the effect of Cattaneo Christov (C–C) heat flux and homogenous heterogeneous (Homo-Hetero) chemical reaction with entropy generation minimization analysis. The assumptions of the viscosity of hybrid nanomaterial fluid and variable thermal conductivity are added characteristics to the inimitability of the flow model. Two kinds of nanoparticles, namely single-wall carbon nanotubes and multi-wall carbon nanotubes with ethylene glycol (EG) as the base fluid are considered. Carbon nanotubes possess diverse applications in daily life including energy storage, drug delivery, cancer treatment, tissue generation, platelet activation, magnetic force microscopy, and microwave absorption, etc. Similarity transformations are utilized to translate the modeled problem into the coupled ordinary differential equations. This system of ordinary differential equations is addressed numerically. The graphical outcomes are scrutinized by utilizing the MATLAB software bvp4c function. The results revealed that the velocity profile decreases for the higher rotation parameter while increases for the escalated slip parameter. Furthermore, the fluid concentration and temperature are on the decline for higher surface catalyzed reaction and thermal relaxation parameters respectively.

A mathematical model is designed to deliberate the flow of an MHD Jeffery nanofluid past a vertically inclined stretched cylinder near a stagnation point. The flow analysis is performed in attendance of thermal radiation, mixed convection and chemical reaction. Influence of thermal and solutal stratification with slip boundary condition is also considered. Apposite transformations are engaged to convert the nonlinear partial differential equations to differential equations with high nonlinearity. Convergent series solutions of the problem are established via the renowned Homotopy Analysis Method (HAM). Graphical illustrations are plotted to depict the effects of prominent arising parameters against all involved distributions. Numerically erected tables of important physical parameters like Skin friction, Nusselt and Sherwood numbers are also give. Comparative studies (with a previously examined work) are also included to endorse our results. It is noticed that the thermal stratification parameter has diminishing effect on temperature distribution. Moreover, the velocity field is a snowballing and declining function of curvature and slip parameters respectively.