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We introduce an acoustic microfluidic platform that efficiently traps and selectively releases individual cells using spherical air cavities embedded in a polydimethylsiloxane (PDMS) substrate for large scale manipulation. 

Because of the increasing demand, high-power, high-rate energy storage devices based on electrode materials have attracted immense attention. However, challenges remain to be addressed to improve the concentration-dependent kinetics of ionic diffusion and understand phase transformation, interfacial reactions, and capacitive behaviors that vary with particle morphology and scanning rates. It is valuable to understand the microscopic origins of ion transport in electrode materials. In this review, we discuss the microscopic transport phenomena and their dependence on ion concentration in the cathode materials, by comparing dozens of well-studied transition metal oxides, sulfides, and phosphates, and in the anode materials, including several carbon species and carbides. We generalize the kinetic effects on the microscopic ionic transport processes from the phenomenological points of view based on the well-studied systems. The dominant kinetic effects on ion diffusion varied with ion concentration, and the pathway- and morphology-dependent diffusion and capacitive behaviors affected by the sizes and boundaries of particles are demonstrated. The important kinetic effects on ion transport by phase transformation, transferred electrons, and water molecules are discussed. The results are expected to shed light on the microscopic limiting factors of charging/discharging rates for developing new intercalation and conversion reaction systems. 

Effective communication is essential for students in construction management and relevant fields. Nevertheless, very little emphasis on communication practices has been placed in the construction management curriculum, and limited communication skills are still widely found among students. Ideal construction site visits not only supplement traditional learning in the classrooms but also provide opportunities to communicate with professionals onsite. However, challenges exist that limit the application of site visits and ultimately reduce such opportunities to practice communication skills with experts on the jobsites. This research aims to help overcome the barriers by proposing a novel approach that leverages 360-degree digital sites with virtual human as conversational partners on site (iVisit-Communicate). In this paper, the design and development processes of iVisit-Communicate were described in detail, followed by a case study of its implementation on a digital site visit to a mechanical room. It was found that most students agreed that iVisit-Communicate provided them an opportunity to practice communication skills. 

Field trips are widely recognized as an essential educational component to connect classrooms with the real world. When students don’t have access to real field trips, virtual ones have been developed by educators and researchers. Pedagogical agents have been applied to serve as a tour guide and educational tool that facilitate students learning in a virtual learning environment. Such agents are computer software generated and controlled entities that replicate or emulate humans. Previous studies have found that adding anthropomorphic traits to pedagogical agents in learning environments has significantly improved students’ learning experience; however, this area has yet been explored in the context of a virtual construction field trip. In this study, a virtual field trip to a complex mechanical room was developed using 360-degree panoramas and a pedagogical agent was employed to lead the tour. This study focuses on one single anthropomorphic trait - deictic gestures, which are pointing gestures used to refer to specific objects – and explores how such trait affects students’ quantitative learning outcomes and feedbacks on four aspects of the agent, including facilitating learning, credibility, human-like, and engaging. It was found that deictic gestures can improve students’ learning performance and attitudes on multiple aspects of the agent.