Aggregation‐caused quenching (ACQ) is a general phenomenon that is faced by traditional fluorescent polymers. Aggregation‐induced emission (AIE) is exactly opposite to ACQ. AIE molecules are almost ...nonemissive in their molecularly dissolved state, but they can be induced to show high fluorescence in the aggregated or solid state. Incorporation of AIE phenomenon into polymer design has yielded various polymers with AIE characteristics. In this review, the recent progress of AIE polymers for biological applications is summarized.
Aggregation induced emission (AIE) polymers are a series of polymers that display enhanced emission upon transforming from isolated molecular state to aggregated state. The recent progress of AIE polymers is summarized from the perspectives of their synthesis, properties, and biological applications.
Exogenous contrast‐agent‐assisted NIR‐II optical‐resolution photoacoustic microscopy imaging (ORPAMI) holds promise to decipher wide‐field 3D biological structures with deep penetration, large ...signal‐to‐background ratio (SBR), and high maximum imaging depth to depth resolution ratio. Herein, NIR‐II conjugated polymer nanoparticle (CP NP) assisted ORPAMI is reported for pinpointing cerebral and tumor vasculatures. The CP NPs exhibit a large extinction coefficient of 48.1 L g−1 at the absorption maximum of 1161 nm, with an ultrahigh PA sensitivity up to 2 µg mL−1. 3D ORPAMI of wide‐field mice ear allows clear visualization of regular vasculatures with a resolution of 19.2 µm and an SBR of 29.3 dB at the maximal imaging depth of 539 µm. The margin of ear tumor composed of torsional dense vessels among surrounding normal regular vessels can be clearly delineated via 3D angiography. In addition, 3D whole‐cortex cerebral vasculatures with large imaging area (48 mm2), good resolution (25.4 µm), and high SBR (22.3 dB) at a depth up to 1001 µm are clearly resolved through the intact skull. These results are superior to the recently reported 3D NIR‐II fluorescence confocal vascular imaging, which opens up new opportunities for NIR‐II CP‐NP‐assisted ORPAMI in various biomedical applications.
An NIR‐II conjugated polymer is synthesized and formulated into uniform nanoparticles via microfluidics. The nanoparticles exhibit strong light absorbance, high photoacoustic sensitivity, excellent photoacoustic stability, and good biocompatibility, which facilitate 3D wide‐field deciphering of tumor margins and brain vasculatures with deep penetration to millimeter, large signal‐to‐background ratio, and high maximum imaging depth to depth resolution ratio.
Two‐photon fluorescence imaging allows in vivo study of biological structures and activities in deep tissues, in which bright fluorophores with high photostability and good biocompatibility are ...highly desirable. Herein, a small‐molecule fluorogen with aggregation‐induced emission (AIEgen) is complexed with fetal bovine serum (FBS) proteins to develop a protein‐sized AIEgen–protein hybrid nanocomposite (TPEPy‐FBS) with bright far‐red/near‐infrared (NIR) emission, excellent photostability, and low phototoxicity for deep and high‐resolution in vivo two‐photon brain vasculature imaging. Upon complexation with FBS, the fluorescence of TPEPy is greatly intensified and a sixfold enhancement is observed with 10% FBS in aqueous media. The yielded TPEPy‐FBS shows good physical stability in aqueous media and the phototoxicity of TPEPy is dramatically inhibited after complexation with FBS. Moreover, TPEPy‐FBS exhibits bright two‐photon fluorescence in far‐red/NIR region and good photostability upon femtosecond laser excitation, which facilitates high performance in vivo imaging. A large imaging depth of 656 µm is obtained in brain vasculature network imaging with a high signal‐to‐background ratio of 234, where a small blood capillary of 1.05 µm can be resolved at an imaging depth of 656 µm. Highlighted is a simple and versatile strategy to develop efficient two‐photon probes for in vivo biological imaging.
A biocompatible protein‐sized two‐photon probe of aggregation‐induced emission fluorogen‐protein nanocomposite with bright far‐red/near‐infrared emission and good water solubility is developed for deep in vivo brain imaging. A large imaging depth of 656 µm of brain vasculature network with resolution as high as 1.05 µm is demonstrated.
Polymeric nanoparticles play important roles in the delivery of a multitude of therapeutic and imaging contrast agents. Although these nanomaterials have shown tremendous potential in disease ...diagnosis and therapy, there have been many reports on the failure of these nanoparticles in realizing their intended objectives due to an individual or a combination of factors, which have collectively challenged the merit of nanomedicine for disease theranostics. Herein, we investigate the interactions of polymeric nanoparticles with biological entities from molecular to organism levels. Specifically, the protein corona formation,
endothelial uptake, and
circulation time of these nanoparticles are systematically probed. We identify the crucial role of nanocarrier lipophilicity, zeta-potential, and size in controlling the interactions between nanoparticles and biological systems and propose a two-step framework in formulating a single nanoparticle system to regulate multiple biological effects. This study provides insight into the rational design and optimization of the performance of polymeric nanoparticles to advance their theranostic and nanomedicine applications.
•The mechanical property of the uncorroded part of steel bars remains unchanged.•The probabilistic models of the minimum effective cross-section area of corroded bars.•The relationship between the ...artificial simulation and the natural environment.•The non-uniform corrosion of the steel bars may change the failure mode of a RC beam.
In general, the corroded reinforced concrete members is induced by the natural environment in existing buildings or by the two artificial accelerated corrosion such as electrochemical method and artificial simulated environment. The deterioration of yield strength of corroded steel bars is mainly caused by the decrease of the effective cross-section area, the randomness and the variability of the corrosion. The position of the yield point occurs at the minimum effective cross-section area. Through the statistical analysis of 1706 groups of experimental data on yield strength of corroded steel bars, the relationship between the minimum effective cross-section area of non-uniform corroded steel bars and the average corrosion ratio under three corrosion conditions has been established. After that, a probabilistic model of minimum effective cross-section area of corroded steel bars has been proposed and, meanwhile, a correction coefficient is suggested to adjust the deviation of the yield strength between the average corrosion ratios of artificial accelerated corrosion and natural environment corrosion. Based on the presented probabilistic model, a reinforced concrete beam member under natural environment was analyzed. It is found that the flexure-shear competition happened during its service life, that is, the failure mode may change because of the non-uniform corrosion. Therefore, the non-uniform corrosion of the corroded RC members should be taken into account seriously in structural design.
A hollow Cu@ZrO2 catalysts was prepared through pyrolysis of Cu-loaded Zr-MOF and the balanced Cu0/Cu+ sites and the abundant Cu-ZrO2 interface enhanced the CO2 conversion to methanol.
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•Hollow Cu@ZrO2 catalysts prepared through pyrolysis of Cu-loaded Zr-MOF for CO2 hydrogenation to methanol.•The highly Cu dispersion and the optimal ratio of Cu0/Cu+ is of significance for methanol production.•Cu-ZrO2 interface as the active region and the surface basic sites enhanced the absorption and activation of CO2.•The CO2 hydrogenation to methanol followed a formate intermediate pathway.
The development of a highly efficient catalyst for CO2 activation and selective conversion to methanol is critical to address the issues associated with the high thermal stability of CO2 and controllable synthesis of methanol. Cu-based catalysts have been widely studied because of the low cost and excellent performance in mild conditions. However, the improvement of catalytic activity and selectivity remains challenging. Herein, we prepared hollow Cu@ZrO2 catalysts through pyrolysis of Cu-loaded Zr-MOF for CO2 hydrogenation to methanol. Low-temperature pyrolysis generated highly dispersed Cu nanoparticles with balanced Cu0/Cu+ sites, larger amounts of surface basic sites and abundant Cu-ZrO2 interface in the hollow structure, contributing to enhanced catalytic capacity for adsorption/activation of CO2 and selective hydrogenation to methanol. In situ Fourier Transform Infrared Spectroscopy revealed the methanol formation followed the formate-intermediated pathway. This work would provide a guideline for the design of high-performance catalysts and the understanding of the mechanism and active sites for CO2 hydrogenation to methanol.
Linguistic q-rung orthopair fuzzy numbers (Lq-ROFNs) are composed of a set of q-rung orthopair fuzzy numbers (q-ROFNs) with membership and nonmembership degrees of linguistic variables, which can be ...regarded as an extension of linguistic intuitionistic fuzzy numbers (LIFNs) and linguistic Pythagorean fuzzy numbers (LPFNs). Compared with LIFNs and LPFNs, Lq-ROFNs have a wider range of applicability because the value of q can have a wider range, thus allowing to handle more multiattribute group decision making (MAGDM) problems. Based on Lq-ROFS, this paper first proposes the Chebyshev distance metric, then develops the Chebyshev distance entropy for deriving objective solution of decision makers’ (DMs’) weight vector and attribute weight vector by combining the metric and entropy measure. The TODIM method has been widely valued by the society and has achieved good results in many MAGDM problems. Subsequently, the TODIM decision method in Lq-ROFS is presented and combined with the Chebyshev distance entropy model as a new decision method (CDE-TODIM) to solve the MAGDM problems. This method process is objective and direct and takes into account the decision maker’s preferences, and the decision results are more persuasive. Finally, the effectiveness and rationality of this MAGDM method are illustrated by a case as well as comparisons.
The belief rule base is crucial in expert systems for intelligent diagnosis of equipment. However, in the belief rule base for fault diagnosis, multiple antecedent attributes are often initially ...determined by domain experts. Multiple fault symptoms related to multiple antecedent attributes are different when an actual fault occurs. This leads to multiple antecedent attributes matching with multiple fault symptoms non-simultaneously, thereby resulting in a fault diagnosis lacking timeliness and accuracy. To address this issue, this paper proposes a method for belief rule-based optimization based on Naive Bayes theory. First, a fault sample is taken in a long enough window and divided into several interval samples, making the analysis samples approximate the overall samples. Second, using Gaussian mixture clustering and Naive Bayes optimization, iteration is performed over the threshold and limit values of fault symptoms in the belief rule base based on the requirements of the timeliness and accuracy of fault diagnosis results. Finally, the belief rule base is optimized. Using fault samples from high-pressure heaters and condensers, the validation results show that there is a there is a significant improvement in the timeliness and accuracy of fault diagnosis with the optimal belief rule base.
Superhydrophobic coating is widely used due to its waterproof and self-cleaning properties. Carbon soot (CS) nanoparticles are naturally superhydrophobic and non-toxic which are superior to other ...superhydrophobic coating. However, the weak binding force of the CS nanoparticle layers hinders their practical application. In this study, micro-nanostructured PET-CS superhydrophobic coatings were prepared by a simple method. The obtained coatings presented durable superhydrophobicity and underwater stability, which are superior to PDMS-CS coatings and CS layers. The coating surfaces demonstrated superhydrophobicity under a water pressure of 13.72 kPa for up to 16 days. The surface could withstand water flush for more than 15 min. The coatings also demonstrated good mechanical stability and maintained superhydrophobicity after an abrasion length of 8 m. The stable long-lasting underwater superhydrophobic surface is of great importance for marine applications.
The warm-temperate regions of the globe characterized by dry summers and wet winters (Mediterranean climate; MED) are especially vulnerable to climate change. The potential impact on water resources, ...ecosystems and human livelihood requires a detailed picture of the future changes in this unique climate zone. Here we apply a probabilistic approach to quantitatively address how and why the geographic distribution of MED will change based on the latest-available climate projections for the 21st century. Our analysis provides, for the first time, a robust assessment of significant northward and eastward future expansions of MED over both the Euro-Mediterranean and western North America. Concurrently, we show a significant 21st century replacement of the equatorward MED margins by the arid climate type. Moreover, future winters will become wetter and summers drier in both the old and newly established MED zones. Should these projections be realized, living conditions in some of the most densely populated regions in the world will be seriously jeopardized.
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