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Vortex-based microfluidics has received significant attention for its unique characteristics of high efficiency, flexible control, and label-free properties for the past decades. Herein, we present a vortex-based acousto-inertial chip that allows both fluid and particle manipulation within a significantly wider flow range and lower excitation voltage. Composed of contraction–expansion array structures and vibrating microstructures combined with bubbles and sharp edges, such a configuration results in more vigorous vortical fluid motions. The overall improvement in device performance comes from the synergistic effect of acoustics and inertia, as well as the positive feedback loop formed by vibrating bubbles and sharp edges. We characterize flow patterns in the microchannels by fluorescence particle tracer experiments and uncover single- and double-vortex modes over a range of sample flow rates and excitation voltages. On this basis, the ability of rapid and efficient sample homogenization up to a flow rate of 200 μL/min under an excitation voltage of 15 Vppis verified by a two-fluid fluorescence mixing experiment. Moreover, the recirculation motion of particles in microvortices is investigated by using a high-speed imaging system. We also quantitatively measure the particle velocity variation on the trajectory and illustrate the capturing mechanism, which results from the interaction of the microvortices, particle dynamics, and composite microstructure perturbations. Further utilizing the shear forces derived by microvortices, our acousto-inertial chip is demonstrated to lysis red blood cells (RBCs) in a continuous, reagent-free manner. The high controllability and multifunction of this technology allow for the development of multistep miniaturized “lab-on-chip” analytical systems, which could significantly broaden the application of microvortex technology in biological, chemical, and clinical applications.

Tissue engineering raised a high requirement to control cell distribution in defined materials and structures. In “ink”-based bioprintings, such as 3D printing and photolithography, cells were associated with inks for spatial orientation; the conditions suitable for one ink are hard to apply on other inks, which increases the obstacle in their universalization. The Magneto-Archimedes effect based (Mag-Arch) strategy can modulate cell locomotion directly without impelling inks. In a paramagnetic medium, cells were repelled from high magnetic strength zones due to their innate diamagnetism, which is independent of substrate properties. However, Mag-Arch has not been developed into a powerful bioprinting strategy as its precision, complexity, and throughput are limited by magnetic field distribution. By controlling the paramagnetic reagent concentration in the medium and the gaps between magnets, which decide the cell repelling scope of magnets, we created simultaneously more than a hundred micrometer scale identical assemblies into designed patterns (such as alphabets) with single/multiple cell types. Cell patterning models for cell migration and immune cell adhesion studies were conveniently created by Mag-Arch. As a proof of concept, we patterned a tumor/endothelial coculture model within a covered microfluidic channel to mimic epithelial-mesenchymal transition (EMT) under shear stress in a cancer pathological environment, which gave a potential solution to pattern multiple cell types in a confined space without any premodification. Overall, our Mag-Arch patterning presents an alternative strategy for the biofabrication and biohybrid assembly of cells with biomaterials featured in controlled distribution and organization, which can be broadly employed in tissue engineering, regenerative medicine, and cell biology research.

Previous research has found that components of the natural and built environment play an important role in regulating ambient temperature. However, existing research regarding the association between these environmental characteristics and thermal exposure has focused mainly at the macro level, leaving this relationship at the individual level underexplored. It remains unknown how the environment functions differently in determining thermal exposure among various types of trips and how this mechanism differs by gender. Using GPS walking trajectory data collected in Nanjing, China, this study examines the extent to which male and female pedestrians experience different levels of thermal exposure, and how the thermal exposure determinants work differently between utilitarian and recreational trips. Descriptive analysis shows that men experience higher per-minute thermal exposure than women, and both male and female pedestrians face higher thermal exposure per minute during utilitarian walks compared to recreational walks. Generalized linear mixed model results indicate that green spaces significantly reduce thermal exposure for both male and female pedestrians during utilitarian walking trips, but this effect only works among women regarding recreational walking. We also identified a negative relationship between water bodies and thermal exposure during recreational walks, but this correlation only occurs among women. Our study suggests that the natural environment’s mitigating effect on thermal exposure differs by gender among different types of walking trips. Policymakers should consider these disparities to avoid exacerbating gender inequality in the arena of thermal exposure and health.

Since there has been a huge amount of transport infrastructure projects being proposed, planned and constructed over the past decades in China, this article aims to reveal the substantial dynamics of China’s rapid development of urban mega-projects. It analyzes Nantong’s metro project to use it as a case study – how it was being justified, approved and implemented, and what were the key driving forces within the whole process through official justifications and key informant interview materials. The urban metro system is supposedly an approach to achieve urban development objectives, a tool for growth and a way to a better urban life. We find inter-city competition as an underlying driving force that initiates such urban mega-projects with certain weight given to economic indicators in project appraisals within a largely local government-led and public-invested process. Furthermore, domestic economic performance and changing policy interventions also exert significant influence on project approval and long-term project development. Our findings echo some Western literature on mega-projects development and urban competition, while revealing other features and emerging issues relating to project initiation, proposal examination and implementation specific to the Chinese context.

Lysine acetylation is a dynamic post-translational modification of proteins. Extensive studies have revealed that the acetylation modulated by histone acetyltransferases and histone deacetylases (HDACs) plays a crucial role in regulating protein function. However, there has been limited focus on how HDACs regulate jasmonic acid (JA) biosynthesis in plants. Here, we uncover that the protein stability of OsLOX14, a critical enzyme involved in JA biosynthesis, is regulated by a histone deacetylase, OsHDA706, and is hindered by a viral protein. Our results show that OsHDA706 deacetylates OsLOX14 and enhances the stability of OsLOX14, leading to JA accumulation and an improved broad-spectrum rice antiviral defense. Furthermore, we found that the viral protein P2, encoded by the destructive rice stripe virus, disrupts the association of OsHDA706-OsLOX14, promoting viral infection. Overall, our findings reveal how HDAC manipulates the interplay of deacetylation and protein stability of a JA biosynthetic enzyme to enhance plant antiviral responses.

AbstractBased on the inadequacies and neglect of the equity of refuge resources, refuge demands and the evacuation allocation of traditional methodologies, this study put forwards the multi-objectives layout optimization model of shelters which firstly realizes the maximum equity of shelter location. Our approach has the objectives of maximizing equity, minimizing overall egress time and minimizing the quantity of new shelters. The high-precision population is established through mobile signaling data, while the optimization model adopts a circular circulatory allocation rule derived from a gravity model. The shorter the evacuation time, the larger the shelter capacity and thus more refugees are allocated to the shelter. The evacuation time is determined by the application programming interface (API) of the Baidu Map open platform with Python, which exhibits the authentic evacuation paths and real-time traffic conditions. This study designs a three-stage algorithm ‘genetic algorithm-exhaustive method-evaluation’. The first process of algorithm calculates the minimum quantity of new shelters; the second process selects the feasible layout schemes and determines Pareto optimum solutions; and the third stage evaluates the Pareto optimum solution based on the shelter construction cost and the accessibility from shelters to emergency supply storage points to determine the best location scheme. This study regards Xin Jiekou district in Nanjing as a case area to demonstrate reliability and availability of the proposed methodology.

Pepper mild mottle virus (PMMoV) is a devastating viral pathogen of pepper (Capsicum annuum) but it is unclear whether and how peppers protect against PMMoV infection. The expression of the chloroplast outer membrane protein 24 (OMP24) of C. annuumwas upregulated under PMMoV infection and it interacted with PMMoV coat protein (CP). Silencing of OMP24in either C. annuumor Nicotiana benthamianafacilitated PMMoV infection, whereas overexpression of N. benthamiana OMP24in transgenic plants inhibited PMMoV infection. Both C. annuumOMP24 (CaOMP24) and N. benthamianaOMP24 (NbOMP24) localized to the chloroplast and have a moderately hydrophobic transmembrane domain that is necessary for their localization. Overexpression of CaOMP24induced stromules, perinuclear chloroplast clustering, and accumulation of reactive oxygen species (ROS), the typical defense responses of chloroplasts transferring the retrograde signaling to the nucleus to regulate resistance genes. The expression of PR1and PR2was also upregulated significantly in plants overexpressing OMP24. Self-interaction of OMP24 was demonstrated and was required for OMP24-mediated plant defense. Interaction with PMMoV CP interfered with the self-interaction of OMP24 and impaired OMP24-induced stromules, perinuclear chloroplast clustering and ROS accumulation. The results demonstrate the defense function of OMP24 in pepper during viral infection and suggest a possible mechanism by which PMMoV CP modulates the plant defense to facilitate viral infection.

Soil microbial communities are critical to plant health and productivity. Crop-associated microbial diversity may exhibit spatial specificity across regions and soil compartments. However, we lack sound evidence for the impact of variation in soil microbial diversity on plant productivity caused by regional differences. The main aims of this study are to explore the structure and functionality of the belowground (potato tuber surface and rhizosphere) microbial communities in three compartments and assess whether these communities contribute to potato productivity. Significant differences in alpha and beta diversities of belowground microbiota were detected in different compartments and regions, mainly due to differences in available soil nutrients and pH. Changes to microbial diversity between bulk soil and rhizosphere or tuber surface soil were significantly negatively correlated with potato yield and nutrient content and positively correlated with starch content. We further found some bacterial (Mucilaginibacter, Dokdonella, and Salinispora) and fungal (Solicoccozyma, Scytalidium, and Humicola) genera closely associated with potato yield and quality. Aggregated boosted tree prediction revealed that soil physicochemical properties and microbial diversity of tuber surface soil contributed more to potato yield; tuber surface soil bacterial contributed more to potato starch and nutrient content. Our findings provide experimental evidence that the significant differences in soil microbial diversity and specific microbial taxa enrichment may potentially influence crop productivity under soil physicochemical property change scenarios in the agricultural ecosystem.

ABSTRACTAutophagy, a bulk degradation system conserved among most eukaryotes, is also involved in responses to viral infection in plant. In our previous study, a new host factor P3IP was identified to interact with RSV (rice stripe virus) p3 and mediate its autophagic degradation to limit the viral infection. Here, we further discovered that P3IP of Nicotiana benthamiana(NbP3IP) participated in regulation of autophagy. Overexpression of NbP3IP induced autophagy and down-regulation of NbP3IP reduced autophagy. Combined the functions of autophagy-mediated plant defense against plant virus and regulation autophagy, we indicate that P3IP participates in the regulation of autophagy.