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A facile strategy for efficient and continuous fabrication of monodisperse gas-core microcapsules with controllable sizes and excellent ultrasound-induced burst performances is developed based on droplet microfluidics and interfacial polymerization. Monodisperse gas-in-oil-in-water (G/O/W) double emulsion droplets with a gas core and monomer-contained oil layer are fabricated in the upstream of a microfluidic device as templates, and then water-soluble monomers are added into the aqueous continuous phase in the downstream to initiate rapid interfacial polymerization at the O/W interfaces to prepare monodisperse gas-in-oil-in-solid (G/O/S) microcapsules with gas cores. The sizes of both microbubbles and G/O/W droplet templates can be precisely controlled by adjusting the gas supply pressure and the fluid flow rates. Due to the very thin shells of G/O/S microcapsules fabricated via interfacial polymerization, the sizes of the resultant G/O/S microcapsules are almost the same as those of the G/O/W droplet templates, and the microcapsules exhibit excellent deformable properties and ultrasound-induced burst performances. The proposed strategy provides a facile and efficient route for controllably and continuously fabricating monodisperse microcapsules with gas cores, which are highly desired for biomedical applications. [ABSTRACT FROM AUTHOR]

A stretchable conductive Janus hydrogel with controllable porous structures is developed for highly sensitive monitoring of human motion. The Janus porous structure of the hydrogel is fabricated using patterned single‐layer droplets produced by microfluidics as pore‐forming templates. The hydrogel possess dual‐crosslinked polymeric networks to achieve good stretchability (480%), which allows fully cover the stretching range of human skin (usually <200%). Meanwhile, the hydrogel possess controllable Janus porous structures with local strain/stress enhancement to achieve high sensitivity (GF = 5.2) for strain‐sensing. The Janus hydrogel shows fast response for stretching (175 ms) and recovery (170 ms), and good durability (200 cycles at 50% strain). The conductive Janus hydrogel with high sensitivity and good mechanical properties are promising for developing soft wearable sensors in fields such as human health monitoring and human motion detection. [ABSTRACT FROM AUTHOR]

Significant achievements have been made in membrane‐based nanofiltration to combat global micropollutant contamination in aquatic environments, but the current water purification membranes have been constrained by the inherent limitations of substantial operating pressure gradients. Here, a novel solution inspired by natural guttation process observed in plants is presented. This biomimetic guttation feature is realized in the 2D hydrotalcite membranes composed of layered double hydroxides (LDHs), which spontaneously exhibit water seepage, akin to the expulsion of excess liquid from plant leaves in nature. This self‐sustaining water permeation is attributed to the surface force‐pore flow mechanism. Unlike conventional membranes requiring external operating pressure, the guttation flux positively correlates with LDH membrane thickness up to a threshold point. Further demonstration shows the potential of the membrane by achieving over 99% rejection of small molecular weight organic dyes, for addressing micropollutant challenges. Leveraging the guttation feature, steric effects related to the d‐spacing, and the chemical safety of LDH, the finding opens multiple opportunities for self‐sustaining nanofiltration and forward osmosis applications, such as pharmaceuticals (e.g., protein purification) and food processing (e.g., fruit juice or milk concentration) standing to benefit significantly from this innovative technology. [ABSTRACT FROM AUTHOR]

The precise, controllable, and safe application of pesticides can effectively reduce pesticide consumption and minimize chemical pollution at the source. Here, a light‐responsive controlled‐release system with flexible control, precise release, easy recovery, and suitability for future pesticide application in aquatic environments is proposed. The system precisely controls the release of pesticides through a light‐responsive composite nanochannel membrane (CTC@SNM/PET) with reactive coumarin derivatives (CTC) as gating molecules. The prepared nanochannel membrane has an ultrathin thickness of 67.5 nm and well‐ordered vertical nanochannels with a uniform size of 1.9 nm, providing a prerequisite for precise molecular gating and high permeability for mass transport. CTC monomers can realize cycloaddition/cyclocracking and nanochannel closing/opening to control the release of pesticides by controlling 365/254 nm ultraviolet light irradiation. As a proof of concept, the light‐responsive controlled‐release system based on CTC@MSF/PET against Saprolegnia parasitica achieves an inhibition rate of more than 95% and reduces pesticide residues by 56.5% compared to the control group. The proposed membrane system has great application potential to easily enable remote, quantitative, timed, and positioned pesticide application, thereby reducing pesticide residues and providing a prospective approach to reducing environmental and human risks. [ABSTRACT FROM AUTHOR]

Controllable mass production of monodisperse droplets plays a key role in numerous fields ranging from scientific research to industrial application. Microfluidic ladder networks show great potential in mass production of monodisperse droplets, but their design with uniform microflow distribution remains challenging due to the lack of a rational design strategy. Here an effective design strategy based on backstepping microflow analysis (BMA) is proposed for the rational development of microfluidic ladder networks for mass production of controllable monodisperse microdroplets. The performance of our BMA rule for rational microfluidic ladder network design is demonstrated by using an existing analogism-derived rule that is widely used for the design of microfluidic ladder networks as the control group. The microfluidic ladder network designed by the BMA rule shows a more uniform flow distribution in each branch microchannel than that designed by the existing rule, as confirmed by single-phase flow simulation. Meanwhile, the microfluidic ladder network designed by the BMA rule allows mass production of droplets with higher size monodispersity in a wider window of flow rates and mass production of polymeric microspheres from such highly monodisperse droplet templates. The proposed BMA rule provides new insights into the microflow distribution behaviors in microfluidic ladder networks based on backstepping microflow analysis and provides a rational guideline for the efficient development of microfluidic ladder networks with uniform flow distribution for mass production of highly monodisperse droplets. Moreover, the BMA method provides a general analysis strategy for microfluidic networks with parallel multiple microchannels for rational scale-up. [ABSTRACT FROM AUTHOR]

A mesocosm experiment was conducted in Wuyuan Bay (Xiamen), China, to investigate the effects of elevated pCO2 on the phytoplankton species Phaeodactylum tricornutum (P. tricornutum), Thalassiosira weissflogii (T. weissflogii) and Emiliania huxleyi (E. huxleyi) and their production ability of dimethylsulfide (DMS), dimethylsulfoniopropionate (DMSP), as well as four halocarbon compounds, bromodichloromethane (CHBrCl2), methyl bromide (CH3Br), dibromomethane (CH2Br2) and iodomethane (CH3I). Over a period of 5 weeks, P. tricornuntum outcompeted T. weissflogii and E. huxleyi, comprising more than 99% of the final biomass. During the logarithmic growth phase (phase I), mean DMS concentration in high pCO2 mesocosms (1000 μatm) was 28% lower than that in low pCO2 mesocosms (400 μatm). Elevated pCO2 led to a delay in DMSP-consuming bacteria concentrations attached to T. weissflogii and P. tricornutum and finally resulted in the delay of DMS concentration in the high pCO2 treatment. Unlike DMS, the elevated pCO2 did not affect DMSP production ability of T. weissflogii or P. tricornuntum throughout the 5-week culture. A positive relationship was detected between CH3I and T. weissflogii and P. tricornuntum during the experiment, and there was a 40% reduction in mean CH3I concentration in the high pCO2 mesocosms. CHBrCl2, CH3Br, and CH2Br2 concentrations did not increase with elevated chlorophyll a (Chl a/ concentrations compared with DMS(P) and CH3I, and there were no major peaks both in the high pCO2 or low pCO2 mesocosms. In addition, no effect of elevated pCO2 was identified for any of the three bromocarbons. [ABSTRACT FROM AUTHOR]

The theory of human body in Yilin Gaicuo (Correction on Errors in Medical Classics) by Wang Qingren in late Qing Dynasty is different from that of traditional Chinese Medicine and that of anatomy of western medicine. However, the prescriptions recorded in Yilin Gaicuo (Correction on Errors in Medical Classics) are indeed effective clinically. The paradox of "Fallacious theory, effective prescription" suggests that the theories of Wang Qingren are not superficial in anatomy. By carefully analyzing the concept of zang-fu organs and concept of qi and blood as well as the theory of human body in Yilin Gaicuo (Correction on Errors in Medical Classics), although many viewpoints of theories of Wang Qingren deviates from that of traditional Chinese Medicine, they inherits the qi and blood concept, the core theory of Chinese Medicine. Therefore, the theories belong to the theoretical scope of Chinese Medicine. The root of "Fallacious theory, effective prescription" is in the heritage of the qi and blood concept. The set view of Wang Qingren in criticizing the theories of traditional Chinese Medicine and establishing new theories revealed in this process possesses the significance of revelation to the contemporary Chinese Medicine.