This paper develops a numerical simulation model to research the deformable particleparticle interactions caused by dielectrophoresis (DEP) under AC electric fields. The DEP force is calculated by using Maxwell stress tensor method, and the hydrodynamic force is obtained by calculating the hydrodynamic stress tensor. Simulation results show that the DEP interactive motion will facilitate the particles forming particle chains that are parallel to the electric field, and the particles with low shear modulus present a lower x-component velocity. Also, the electric field intensity and particles radius have some effects on the DEP motions, and for different particles, smaller particles with larger electric field intensity easily reach a larger velocity. The numerical research may provide universal guidance for biological cells manipulation and assembly.

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The dielectrophoretic (DEP) choking phenomenon is revisited for Janus particles that are transported electrokinetically through a microchannel constriction by a direct‐current (DC) electric field. The negative DEP force that would block a particle with a diameter significantly smaller than that of the constriction at its inlet is seen to be relaxed by the rotation of the Janus particle in a direction that minimizes the magnitude of the DEP force. This allows the particle to pass through the constriction completely. An arbitrary Lagrangian‐Eulerian (ALE) numerical method is used to solve the nonlinearly coupled electric field, flow field, and moving particle, and the DEP force is calculated by the Maxwell stress tensor (MST) method. The results show how Janus particles with non‐uniform surface potentials overcome the DEP force and present new conditions for the DEP choking by a parametric study. Particle transportation through microchannel constrictions is ubiquitous, and particle surface properties are more likely to be non‐uniform than not in practical applications. This study provides new insights of importance for non‐uniform particles transported electrokinetically in a microdevice.

The adversities of a changing climate in developing countries and the related impact on agriculture are directly dependent on the adaptive behavior of local farmers towards climate change events. The perception of farmers as basic executers of agricultural production plays a crucial role in their adaptation decisions. Through a field survey of 200 farmers in Hainan, China, this study covers the methodological gap in determining the reactive adaptations for coping with the changing climate and the underlying factors of farmers’ adaptive behavior. The results indicated that the smallholder farmers are well aware of climate change, and the majority of them are taking adaptive measures such as following up on weather forecast, changing crop varieties, conserving agriculture through soil conservation and/or agroforestry, modifying different farm operations, increasing investment in infrastructure, increasing non-agricultural income of household, switching to new genetically modified cultivars, and engaging in water conservation methods. A binary logistic regression analysis was performed to study the determinants of farmers’ adaptive behavior, and the results highlighted 10 significant factors affecting farmers’ adaptations, including the age and gender of the farmer, non-agricultural income, training, credit access, policy demand, and perceived changes in climate change events. Our results are in line with the extant literature. The percentage of consistency (POC) was also calculated to evaluate the BLR results, and the overall POC was 60.7%. On the policy front, several suggestions are made based on derived conclusions, such as arranging training programs as a supplement to policymaking, incorporating significant factors for the development of high protection capacity, accounting for gender differences, and supporting crop insurance via subsidies.

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