Three-dimensional nano-biointerface has been emerging as an important topic for chemistry, nanotechnology, and life sciences in recent years. Understanding the exchanges of materials, signals, and ...energy at biological interfaces has inspired and helped the serial design of three-dimensional nano-biointerfaces. The intimate interactions between cells and nanostructures bring many novel properties, making three-dimensional nano-biointerfaces a powerful platform to guide cell fate in a controllable and accurate way. These advantages and capabilities endow three-dimensional nano-biointerfaces with an indispensable role in developing advanced biological science and technology. This tutorial review is mainly focused on the recent progress of three-dimensional nano-biointerfaces and highlights the new explorations and unique phenomena of three-dimensional nano-biointerfaces for cell-related fundamental studies and biomedical applications. Some basic bio-inspired principles for the design and creation of three-dimensional nano-biointerfaces are also delivered in this review. Current and further challenges of three-dimensional nano-biointerfaces are finally addressed and proposed.
To explore the impact mechanism of principals’ transformational leadership on students’ modernity, this study adopted the structural equation model to test the multiple mediating effects of school ...climate, teacher quality, and effective teaching on the relationship between principals’ transformational leadership and students’ modernity. Results showed that there was a positive correlation between principals’ transformational leadership and students’ modernity; school climate, teacher quality, and effective teaching fully mediated the relationship between principals’ transformational leadership and students’ modernity, totally accounting for 64.37% of all the indirect effects; the mediating effects of school climate, teacher quality, and effective teaching, respectively, accounted for 30.20%, 52.29%, and 17.51%. According to these results, principal should adopt the approach of transformational leadership, promote the constructing of a fair, inclusive and innovative school climate, emphasize the improvement of teachers’ social, emotional, and innovative qualities, and encourage teachers to reflect their teaching and conduct rational practices to improve students’ modernity.
•A novel layered Ta doped NiFe LDH for electrochemical water splitting catalysis.•Intrinsic electron transfer from Fe to Ta was observed in Ta-NiFe LDH.•The increased activity of OER is due to the ...low coordination state at the Ta-doping site.
Structural manipulation of electrocatalyst via doping strategy has always held great interests for developing advanced and stable non-noble metal electrocatalyst for oxygen evolution reaction (OER). Herein, a high-valence state tantalum (Ta) was incorporated into the pristine NiFe layered double hydroxide (LDH) by hydrothermal method. Interestingly, as revealed by structural characterizations, Ta doping causes the lattice expansion of LDH and electronic structure modification through electron transfer from Fe to Ta. DFT calculations further verified that the modulated electronic structure among Ni, Fe and Ta and the modified eg orbital of Ta induced by charge transfer are beneficial for the adsorption of OH species on Ta site in Ta-doped NiFe LDH and increasing the intrinsic metallic property of NiFe LDH. Consequently, the Ta site has lower overpotential compared with other sites on NiFe LDH including the pristine oxygen vacancies, which can improve the electrocatalytic activity for OER. Furthermore, the optimized Ta-NiFe LDH (0.5:6:1.5) exhibited a superior OER activity in contrast to bimetallic LDH, with a low overpotential of 260 mV to drive the current density of 50 mA·cm−2 and a small Tafel slope of 58.95 mV·dec-1. This work provides the theoretical basis for the enhancement of electrochemical OER activity by doping LDH with high-valence state foreign metal.
In nature, many organisms are able to accommodate a complex living environment by developing biological wet adhesive surfaces with unique functions such as fixation and predation. Significantly, most ...of these outstanding functions originate from the specialized micro/nanostructures and/or chemical components of these natural organisms. To design artificial surfaces with remarkable wet adhesive properties, the underlying mechanisms of the fascinating adhesion phenomena are further explored and summarized to provide continuous inspiration. Herein, a systematic overview of biological wet adhesive surfaces and the corresponding artificial counterparts from the perspective of surface micro/nanostructures is provided. First, the research progress of the typical biological wet adhesive surfaces such as the octopus, tree frogs, and mayfly larvae is introduced. Then, the fundamental models of surface adhesion in natural organisms and the commonly used instruments for measuring adhesion force are discussed. Later, the corresponding artificial wet adhesive surfaces inspired by these representative organisms are highlighted. After that, the typical methods for fabricating these surfaces are briefly introduced. Finally, future challenges and opportunities to develop bioinspired multiscaled wet adhesive surfaces with controlled adhesion are presented.
Bioinspired wet adhesive surfaces have been arousing great attention in various fields. The current advances of the typical wet adhesive surfaces are summarized from the perspective of micro/nanostructures, followed by a discussion of fundamental models and characterizations. The corresponding artificial surfaces and typical fabrication methods are then introduced. Finally, future challenges and opportunities for developing multiscale adhesive surfaces are presented.
Inspired by the swimming of natural microorganisms, synthetic micro‐/nanomachines, which convert energy into movement, are able to mimic the function of these amazing natural systems and help ...humanity by completing environmental and biological tasks. While offering autonomous propulsion, conventional micro‐/nanomachines usually rely on the decomposition of external chemical fuels (e.g., H2O2), which greatly hinders their applications in biologically relevant media. Recent developments have resulted in various micro‐/nanomotors that can be powered by biocompatible fuels. Fuel‐free synthetic micro‐/nanomotors, which can move without external chemical fuels, represent another attractive solution for practical applications owing to their biocompatibility and sustainability. Here, recent developments on fuel‐free micro‐/nanomotors (powered by various external stimuli such as light, magnetic, electric, or ultrasonic fields) are summarized, ranging from fabrication to propulsion mechanisms. The applications of these fuel‐free micro‐/nanomotors are also discussed, including nanopatterning, targeted drug/gene delivery, cell manipulation, and precision nanosurgery. With continuous innovation, future autonomous, intelligent and multifunctional fuel‐free micro‐/nanomachines are expected to have a profound impact upon diverse biomedical applications, providing unlimited opportunities beyond one's imagination.
Fuel‐free synthetic micro‐/nanomachines powered by external stimuli are able to swim efficiently in biologically relevant environments. Tremendous progress made in the past decade to develop different synthesis strategies for designing and fabricating fuel‐free micro‐/nanomotors with different functionalities is reviewed. These artificial nanomachines can achieve predetermined tasks in biomedical applications.
Superwetting surfaces in air, such as superhydrophobic and superoleophobic surfaces that are governed by surface chemical compositions and surface topographies, are one of the most extensively ...studied topics in this field. However, it is not well‐understood how surface topographies affect the behaviors of immiscible liquids and gases under other kinds of media, although it is significant in diverse fields. The main aim of this work is to systematically investigate the wetting behaviors of liquids (water and oil) and gas (air) on silicon surfaces with different topographies (i.e., smooth, micro, nano, and micro‐/nanostructures) under various media (i.e., air, water, and oil). The contact angles, as well as contact‐angle hysteresis, sliding angles, and adhesive forces, were utilized to evaluate the wettability of these surfaces. As a result, the microstructured surfaces typically exhibit high contact‐angle hysteresis, high sliding angles, and high adhesive forces, whereas the micro‐/nanostructured surfaces display low contact‐angle hysteresis, low sliding angles, and low adhesive forces, even if they have high (>150°) and similar contact angles. Furthermore, when transferring the same surface from one kind of medium to another, different superwetting states can be reversibly switched.
Regulating the surface topographies (i.e., smooth, micro, nano, and micro‐/nanostructures), the static and dynamic behaviors of liquids (water and oil) and air on the surfaces, as well as the transition of wetting states under various media (i.e., air, water, and oil) can be easily controlled.
This study aimed to determine the mediating effects of school climate on the relationship between school heads’ transformational leadership and students’ modernity. We asked teachers to report on ...their school heads’ transformational leadership, school climates, and students’ modernity. Data were collected from 378 teachers from 42 middle and primary schools in five provinces in mainland China. Structural equation modeling (SEM) was adopted to test multiple mediating effects. Results indicated that school climates, including affiliation climate, innovation climate, and justice climate, were significantly affected by school heads’ transformational leadership. All these three school climates had positive effects on students’ modernity, and partially mediated the relationship between school heads’ transformational leadership and students’ modernity. These three mediating variables accounted for 35.1% of the total indirect effects; the innovation climate accounted for 15.6% of the total indirect effects, followed by justice climate (11.7%) and affiliation climate (7.8%). Results suggest that school climates are important factors that need special attention when school heads wish to develop students’ modernity. In the implementation of transformational leadership, the combination of school climates and the establishment of innovation, justice, and affiliation climates should be emphasized.
•Biochar, peat bog and zeolite addition for composting were studied.•Biochar addition showed most significantly effect on composting.•The data provide valuable information for improving composting ...maturity.
A batch composting study was performed to evaluate effects of biochar addition on dynamics of microbial community and changes of key physic-chemical properties during composting of tomato stalk and chicken manure. As a comparison, two amendments of peat bog and zeolite were selected. The results indicated that biochar addition for composting showed a shorter time to enter thermophilic phase (3 d) and a higher temperature (56°C) and longer duration of thermophilic phase compared to that of peat bog addition, zeolite addition and raw composts. The highest C/N ratio and volatile fatty acids’ concentration with biochar addition were obtained. Biochar addition also showed more influence on bacterial community changes than that of peat bog and zeolite. Thus, biochar addition could significantly affect physic-chemical process and microbial community diversity on tomato stalk and chicken manure composting. This study provides valuable information for improving composting and a better understanding of biodegradation processes.
A novel superhydrophilic and underwater superoleophobic polyacrylamide (PAM) hydrogel‐coated mesh is successfully fabricated in an oil/water/solid three‐phase system. Compared to traditional ...oleophilic materials, the as‐prepared hydrogel‐coated meshes can selectively separate water from oil/water mixtures with the advantages of high efficiency, resistance to oil fouling, and easy recyclability.
Cell adhesion behaviors of stimuli-responsive surfaces have attracted significant attention for their potential biomedical applications. Distinct from temperature and pH stimuli, photoswitching ...avoids the extra input of thermal energy or chemicals. Herein, we designed a novel reusable cyclodextrin (CD)-modified surface to realize photoswitched specific cell release utilizing host–guest interactions between CD and azobenzene. The azobenzene-grafted specific cell capture agent was assembled onto the CD-modified surface to form a smart surface controlling cell adhesion by light radiation. After UV light irradiation, the azobenzene switched from trans- to cis-isomers, and the cis-azobenzene was not recognized by CD due to the unmatched host–guest pairs; thus, the captured MCF-7 cells could be released. Light-triggered specific cancer cell release with high efficiency may afford a smart surface with significant potential applications for the isolation and analysis of circulating tumor cells.
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