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Cylindrical polymer brushes with different iRGD conjugation densities were synthesized and iRGD density effects on their biological properties were obtained.

Timely lysosome escape is of paramount importance for endocytosed nanomedicines to avoid premature degradation under the acidic and hydrolytic conditions in lysosomes. Herein, we report an exciting finding that phenylboronic acid (PBA) modification can greatly facilitate the lysosome escape of cylindrical polymer brushes (CPBs). On the basis of our experimental results, we speculate that the mechanism is associated with the specific interactions of the PBA groups with lysosomal membrane proteins and hot shock proteins. The featured advantage of the PBA modification over the known lysosome escape strategies is that it does not cause significant adverse effects on the properties of the CPBs; on the contrary, it enhances remarkably their tumor accumulation and penetration. Furthermore, doxorubicin was conjugated to the PBA-modified CPBs with a drug loading content larger than 20%. This CPBs-based prodrug could eradicate the tumors established in mice by multiple intravenous administrations. This work provides a novel strategy for facilitating the lysosome escape of nanomaterials and demonstrates that PBA modification is an effective way to improve the overall properties of nanomedicines including the tumor therapeutic efficacy.

Aggregation-induced emission (AIE) fluorophores with second near-infrared window (NIR-II) fluorescence are very promising for in vivo imaging because they emit fluorescence in an aggregated state and provide desirable imaging resolution and depth. Up to now, only a limited number of NIR-II AIE fluorophores have been developed. Therefore, synthesizing novel NIR-II AIE fluorophores and investigating structural effects on their photophysical properties are very important for the development of AIE probes. In this work, we synthesized two donor-acceptor-donor-type NIR fluorophores with emissions extending into the NIR-II window named DPTQ-PhPTZ and DPTQ-PhPXZ with phenothiazine (PTZ) and phenoxazine (PXZ) derivatives as the electron donors, respectively, and studied their photophysical properties via theoretical and experimental approaches as well as the properties in NIR-II in vivo imaging. The PTZ and PXZ moieties provided typical AIE characteristics. Despite the very similar chemical structures of PTZ and PXZ, DPTQ-PhPTZ and DPTQ-PhPXZ exhibited rather different photophysical properties, for example, compared to DPTQ-PhPTZ, DPTQ-PhPXZ had higher quantum yield (QY) both in solution and in the aggregated state and its QY was less sensitive to solvent polarity. After being coated with an amphiphilic copolymer F-127, the fluorophores maintained fluorescence, and the formed fluorescent polymer nanoparticles (NPs) had satisfactory tumor accumulation and biocompatibility, implying that they are applicable for in vivo tumor detection.

Traditional organic fluorophores generally have hydrophobic conjugated backbones and exhibit an aggregation-caused quenching emission property, which limits greatly their applications in the biological field. Aggregation-induced emission (AIE) fluorophores can breakthrough this shortcoming and are more promising in biological imaging. In this paper, we synthesized three novel donor-acceptor-donor-type second near-infrared (NIR-II) fluorophores and studied their geometric and electronic structures and photophysical properties by both theoretical and experimental studies. All the three fluorophores had typical AIE characteristics, and their emission wavelength spanned the traditional near-infrared and NIR-II regions. They exhibited much stronger fluorescence after being encapsulated in polymer nanoparticles (NPs) than in solutions, and the fluorophore-loaded NPs had desirable biosafety and significant tumor accumulation, indicating that they have great application potentials in tumor detection.

Building the rail transit photovoltaic power station (RTPPS) to improve the utilization rate of renewable energy has become an effective way to reduce carbon emissions. Unlike the photovoltaic power stations built in the wide area, the urban rail transit in the big city must consider the demand of landscape, the nearby utilization of electric energy and the impact of light pollution on residents. Hence selecting a reasonable RTPPS plan is important, but it is still the research gap. There are still some problems encountered in the RTPPS plan selection. First, there is lack of an effective decision index system of RTPPS plan selection; second, the existing decision model cannot effectively balance three kind relationships: ①the expression convenience of decision preference and ability to deal with uncertainty; ② the subjectivity and objectivity of the criteria weights in the linguistic environment; ③ the overall effectiveness and local disadvantages of the RTPPS plan. Therefore, the proposed decision index system is established from five aspects: economic performance, rationality of photovoltaic integrated design, effectiveness of light pollution control, energy efficiency and support degree. Meanwhile, according to the principle of probabilistic linguistic term set, combination weighting method and VIKOR model, the corresponding model was proposed to balance tha above relationships. It has the following characteristics：① it improves the ability to deal with uncertain information without changing the expression habit of expert decision preference; ② The weight of decision criterion not only reflects the subjective intention of decision-makers, but also avoids too subjective decision-making; ③ The local disadvantages of the plan are considered in the final result, so as to ensure that the optimal alternative will not be abandoned because of the local disadvantages. The proposed decision index system and decision model jointly construct the optimal plan selection framework of RTPPS to improve the plan selection rationality. The effectiveness of this framework is proved by a China case study.

Cyclic polymers have an intriguing endless architecture and exhibit unique biological properties. However, the reported cyclic polymers either adopt loosely curled conformations or exist in closely packed states, and thus their distinct biological properties are mostly attributed to their endless feature or different packing behaviors and not directly related to the ringlike morphology. Up to now, the biological properties of the polymers with a ringlike morphology still remain unknown. Herein, for the first time, we investigate the in vitro and in vivo properties of the cyclic cylindrical polymer brushes (CPBs) with a ringlike morphology and present an important finding that cyclic CPBs are more prone to non-specific protein adsorption than their linear counterparts with the same chemical composition and contour length due to their lower flexibility. This finding can explain the fact that although cyclic CPBs have lower cellular uptake in different cell lines and lower phagocytosis in macrophage cells than linear CPBs, they exhibit relatively shorter blood circulation and higher liver and spleen uptake, which further leads to lower tumor accumulation. Additionally, we also found that the endless character of cyclic CPBs imparted to them lower tumor permeability. Even so, the cyclic CPBs still exhibited excellent passive tumor targeting ability and their tumor uptake reached about 8.2% of the injected dose per gram of tissue (ID/g) after a single intravenous administration. These fundamental findings have important implications not only for a deeper understanding of cyclic polymers but also for guiding the design of biomaterials.

To enhance the water solubility of α-cyclodextrin (CD) polyrotaxanes (PRs) and achieve effective drug loading, we polymerized 2-hydroxyethyl methacrylate and 2-tert-butoxy-N-(2-(methacryloyloxy)ethyl)-N,N-dimethyl-2-oxoethanaminium successively from a α-CD-PR-based macroinitiator by a two-step ATRP followed by cleaving the tert-butyl ester groups, providing a α-CD-PR-cored multiarm copolymer. The multiarm copolymer had reactive hydroxyl pendant groups in the inner block of the arms, which were used to incorporate antitumor agent paclitaxel (PTX). The outer block of the arms was zwitterionic poly(carboxybetaine) and had high hydrophilicity and zero net electric charge in a neutral environment. This feature endowed the PTX-loaded multiarm copolymer with high water solubility and prolonged blood circulation. The blood circulation half-life of the PTX-loaded multiarm copolymer was determined to be about 7.7 h versus 18.8 ± 1.5 min of the reported blood circulation half-life of the PTX injected as commercial T...

The satisfaction degree with the hotel practice base not only embodies the quality of teaching, but also reflects the management level of hotel to some extent. Applying SPSS19.0 statistical software technology, by bias analysis and reliability and validity test, The paper makes analysis on the survey data about satisfaction degree with practice hotels for students of grades 2009 and 2010 majored in tourism management in Hefei University by means of mathematical models on reliability analysis, validity analysis and difference test etc. comes to the conclusion that University-enterprise cooperation has obtained the greatest satisfaction and Satisfaction degree of students has obtained the least satisfaction among the factors affecting the satisfaction with the practice base of students. In addition, the internship satisfaction of students varies greatly with hotels of different cooperation degrees, different levels of hotels and different departments.

This paper applies Application of Count Data Models based on Data Ming technology by the index of Familiarity Degree of Scenic Destination and the index of Competitive State to carry out quantitative analysis on the inbound tourism market of Jiangxi Province in 2001-2012. The results show that: Most inbound tourism source markets are with low familiarity degree or strong unfamiliarity degree. The inter-annual variability of the familiarity degree of inbound tourism source markets shows three concurrent trends of high-position oscillation, middle- position volatility, and low-position coexistence, with significant disparities among source markets; competitive state of the tourist source markets mainly concentrates in Skinny-Dog Market and Children Market. These indicate there are considerable spatial disparities among the inbound tourism source markets of Jiangxi Province, the overall development situation is not optimistic, and it is necessary to carry out further strengthened development and study on the tourism source markets of the Jiangxi province in order to further improve the development of inbound tourism and realize its goal to build a competitive tourism in Jiangxi province.