Conspectus Due to the complexity of biological systems and samples, specific capture and targeting of certain biomolecules is critical in much biological research and many applications. ...cis-Diol-containing biomolecules, a large family of important compounds including glycoproteins, saccharides, nucleosides, nucleotides, and so on, play essential roles in biological systems. As boronic acids can reversibly bind with cis-diols, boronate affinity materials (BAMs) have gained increasing attention in recent years. However, real-world applications of BAMs are often severely hampered by three bottleneck issues, including nonbiocompatible binding pH, weak affinity, and difficulty in selectivity manipulation. Therefore, solutions to these issues and knowledge about the factors that influence the binding properties are of significant importance. These issues have been well solved by our group in past years. Our solutions started from the synthesis and screening of boronic acid ligands with chemical moieties favorable for binding at neutral and acidic pH. To avoid tedious synthesis routes, we proposed a straightforward strategy called teamed boronate affinity, which permitted facile preparation of BAMs with strong binding at neutral pH. To enhance the affinity, we confirmed that multivalent binding could significantly enhance the affinity toward glycoproteins. More interestingly, we observed that molecular interactions could be significantly enhanced by confinement within nanoscale spaces. To improve the selectivity, we investigated interactions that govern the selectivity and their interplays. We then proposed a set of strategies for selectivity manipulation, which proved to be useful guidelines for not only the design of new BAMs but also the selection of binding conditions. Applications in metabolomic analysis, glycoproteomic analysis, and aptamer selection well demonstrated the great potential of the prepared BAMs. Molecular imprinting is an important methodology for creating affinity materials with antibody-like binding properties. Boronate affinity-based covalent imprinting is a pioneering approach in molecular imprinting, but only a few cases of successful imprinting of glycoproteins by this method were reported. With sound understanding of boronate affinity, we developed two facile and generally applicable boronate affinity-based molecular imprinting approaches. The resulting boronate affinity molecularly imprinted polymers (MIPs) exhibited dramatically improved binding properties, including biocompatible binding pH range, enhanced affinity, improved specificity, and superb tolerance to interference. In terms of nanoconfinement effect, we explained why the binding pH range was widened and why the affinity was enhanced. The excellent binding properties made boronate affinity MIPs appealing alternatives to antibodies in promising applications such as disease diagnosis, cancer-cell targeting, and single-cell analysis. In this Account, we survey the key aspects of BAMs, the efforts we made to solve these issues, and the connections between imprinted and nonimprinted BAMs. Through this survey, we wish to pave a sound fundamental basis of the dependence of binding properties of BAMs on the nature and structure of the ligands and the supporting materials, which can facilitate the development and applications of BAMs. We also briefly sketch remaining challenges and directions for future development.
Gold-thiol contacts are ubiquitous across the physical and biological sciences in connecting organic molecules to surfaces. When thiols bind to gold in self-assembled monolayers (SAMs) the fate of ...the hydrogen remains a subject of profound debate-with implications for our understanding of their physical properties, spectroscopic features and formation mechanism(s). Exploiting measurements of the transmission through a molecular junction, which is highly sensitive to the nature of the molecule-electrode contact, we demonstrate here that the nature of the gold-sulfur bond in SAMs can be probed via single-molecule conductance measurements. Critically, we find that SAM measurements of dithiol-terminated molecular junctions yield a significantly lower conductance than solution measurements of the same molecule. Through numerous control experiments, conductance noise analysis and transport calculations based on density functional theory, we show that the gold-sulfur bond in SAMs prepared from the solution deposition of dithiols does not have chemisorbed character, which strongly suggests that under these widely used preparation conditions the hydrogen is retained.
Rural population has continually declined in response to the rapid urbanization process occurring in China, and the related negative socioeconomic impacts on rural development have attracted ...considerable attention from scholars. Currently, few studies have investigated the eco-environmental impact of rural population decline. By employing remote-sensing data, including land-use and normalized difference vegetation index (NDVI) data, this study proposed a method based on the eco-environmental quality index (EQI) to measure the changes in the rural eco-environmental quality (REQ) at the prefectural level from 2000 to 2020. Then, we examined the impacts of rural population decline on REQ variations. We found that (1) most of the research units experienced continuous rural population decline during the research period, with the rural population density declining more than 25% from 2010 to 2020 in approximately half of the research units; (2) the REQ improved in most of the units, especially in the western region, but there were still many units that experienced a decline in the REQ, which were primarily concentrated in the coastal and central regions; (3) rural population decline improved the REQ, but its impacts varied regionally; and (4) rural population density, natural factors, and eco-environmental protection programs had significant influences on REQ variations. These findings may provide a reference for sustainable-development policies in rural China and other developing countries.
Boronate affinity materials, as unique sorbents, have emerged as important media for the selective separation and molecular recognition of cis-diol-containing compounds. With the introduction of ...boronic acid functionality, boronate affinity materials exhibit several significant advantages, including broad-spectrum selectivity, reversible covalent binding, pH-controlled capture/release, fast association/desorption kinetics, and good compatibility with mass spectrometry. Because cis-diol-containing biomolecules, including nucleosides, saccharides, glycans, glycoproteins and so on, are the important targets in current research frontiers such as metabolomics, glycomics and proteomics, boronate affinity materials have gained rapid development and found increasing applications in the last decade. In this review, we critically survey recent advances in boronate affinity materials. We focus on fundamental considerations as well as important progress and new boronate affinity materials reported in the last decade. We particularly discuss on the effects of the structure of boronate ligands and supporting materials on the properties of boronate affinity materials, such as binding pH, affinity, selectivity, binding capacity, tolerance for interference and so on. A variety of promising applications, including affinity separation, proteomics, metabolomics, disease diagnostics and aptamer selection, are introduced with main emphasis on how boronate affinity materials can solve the issues in the applications and what merits boronate affinity materials can provide.
Inconel 718 superalloy has been fabricated by selective laser melting technology (SLM). Its microstructure and mechanical properties were studied under solution+aging (SA) standard heat treatment, ...homogenization+solution+aging (HSA) standard heat treatment and as-fabricated conditions. Precipitated phases and microstructures were examined using OM, SEM, TEM and X-ray analysis methods. The fine dendrite structures with an average dendrite arm spacing of approximately 698nm accompanying some interdendritic Laves phases and carbide particles can be observed in the as-fabricated materials. After standard heat treatments, dendrite microstructures are substituted by recrystallization grains, and Laves phases also dissolve into the matrix to precipitate strengthening phases and δ particles. The test values of all specimens meet Aerospace Material Specification for cast Inconel 718 alloy, and the transgranular ductile fracture mode exists for the three conditions. The strength and hardness of heat-treated SLM materials increase and are comparable with wrought Inconel 718 alloy, whereas their ductility decreases significantly compared with the as-fabricated material. This is because of the precipitation of fine γˊ and γ〞strengthening phases and needle-like δ phases. For the as-fabricated alloy, the formation of finer dislocated cellular structures that develop into a ductile dimple fracture shows excellent ductility. Due to dislocation pinning from γˊ and γ〞strengthening phases and the impediment of dislocation motion caused by the needle-like δ phases, the ductility of the SA materials decreases and causes a transgranular fracture, compared with the as-fabricated samples.
Molecularly imprinted polymers (MIPs), as inexpensive and stable substitutes of antibodies, have shown great promise in immunoassays. Glycoproteins are of significant diagnostic value. To facilitate ...the application of MIPs in clinical diagnostics, a general and facile imprinting method toward glycoproteins oriented for an enzyme-linked immunosorbent assay (ELISA) in the form of a 96-well microplate is essential but has not been fully explored yet. In this study, a new method called boronate affinity-based oriented surface imprinting was proposed for facile preparation of glycoprotein-imprinted microplates. A template glycoprotein was first immobilized by a boronic acid-modified microplate through boronate affinity binding, and then, a thin layer of polyaniline was formed to cover the microplate surface via in-water self-copolymerization. After the template was removed by an acidic solution, 3D cavities that can rebind the template were fabricated on the microplate surface. Using horseradish peroxidase (HRP) as a model target, the effects of imprinting conditions as well as the properties and performance of the prepared MIPs were investigated. α-Fetoprotein (AFP)-imprinted microplate was then prepared, and thereby, a MIP-based ELISA method was established. The prepared MIPs exhibited several highly favorable features, including excellent specificity, widely applicable binding pH, superb tolerance for interference, high binding strength, fast equilibrium kinetics, and reusability. The MIP-based ELISA method was finally applied to the analysis of AFP in human serum. The result was in good agreement with that by radioimmunoassay, showing a promising prospect of the proposed method in clinical diagnostics.
The study focuses on examining the impact of R&D and industrialization on green economic growth. Financial assistance for environmentally friendly initiatives, the advancement of new technologies, ...and the growth of a green economy may all be achieved via green financing. Because of this, it is a key driver of green economic development and industrial structural change. This investigates the impact of renewable energy, R&D, and industrialization on the green economic growth of the South Asian region from 2008 to 2020. The endogeneity of this connection is addressed using a two-step ordinary least square (O.L.S.). The findings show that upgrading industries and R&D reduce carbon emissions and achieve green economic recovery. As a result, 33.4% of the energy was saved, and 35.2% of the emissions were reduced. The partial mediation impact findings show the policy's affecting framework. The empirical results showed that technology spillover had the most responsibility to minimize tiers of CO2 emissions, accompanied by improvements in industrial structure change. Our findings suggest that developing nations gain more from the industrialization initiative than developed countries because of the stronger economic impacts of the strategy.
•There is a dire need to measure the relationship between green finance and renewable energy.•The development of green economic growth, R & D and green finance has been measured.•The green economic growth rate reduces for every unit increase in green finance.•The latent variables account for more than half of the natural variation in all relevant variables.
This article presents a modified equivalent-input-disturbance (MEID) approach that actively rejects exogenous disturbances. A dynamic compensator is newly introduced in a conventional ...equivalent-input-disturbance (EID) estimator to further suppress the disturbances. The mechanism of the MEID approach to improving disturbance rejection is analyzed based on the transfer characteristic from the EID to the output of the system, and a stability condition of the MEID control system is presented and is used to design the parameters of the system. A comparison with the conventional EID approach and the disturbance-observer method through experiments demonstrates the validity of the presented method.
Liver fibrosis is a reversible pathological overreaction during the self‐repair of liver injuries, and it is the common period of chronic liver diseases induced by different pathogenesis progress ...into cirrhosis and even hepatocellular carcinoma. Pyroptosis, a novel form of programmed cell death, is reported to take part in the pathogenesis and progression of acute or chronic liver diseases and liver fibrosis. Caspase‐1 dependent canonical pathway and caspase‐4/‐5/‐11 mediated noncanonical pathway are the two signalling pathways to induce pyroptosis. The activation of inflammasomes under the stimulation of pathogenic microorganisms and danger signals can initiate the pyroptotic pathway and release large amounts of proinflammatory and profibrotic cytokines. This article comprehensively summarizes recent researches focused on the mechanism of pyroptosis and its role in major hepatic cells, which can provide potential therapeutic strategies for liver fibrosis.
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