Partner Achievements | |||||
Title | First Author | Journal | Abstract | DOI | |
1 | Wound microenvironment sensing and self-adjusting hydrogel with glucose, ROS, and MMP-9 responsiveness for improving microcirculation of diabetes foot ulcers | YUAN Yang | Chemical Engineering Journal | Improvements in microcirculation and neovascularization are critical to diabetic foot ulcer (DFU) healing. However, the adverse wound microenvironment hinders the healing process. Therefore, a wound microenvi-ronment sensing and self-adjusting hydrogel, with glucose, reactive oxygen species (ROS) and matrix metal-loproteinase 9 (MMP-9) responsiveness, was fabricated via boronic ester bonds between 3-carboxyphenylboronic acid-grafted chitosan (CS-BA) and epigallocatechin gallate (EGCG) and imine bonds between CS-BA and oxidized hyaluronic acid, in which deferoxamine-loaded gelatin microspheres was loaded. The multi-layer drug loading enabled the earlier release of EGCG for ROS scavenging and anti-inflammation by responding to ROS and hy-perglycemia, and the later release of deferoxamine to promote angiogenesis by responding to overexpressed MMP-9. The responsive degradation and responsive drug release enabled the hydrogel to sense the DFU microenvironment. Chicken embryo allantoic membrane test and tube formation revealed that the hydrogel had outstanding proangiogenic performance and improved the microcirculation. The hydrogel adjusted the DFU microenvironment to promote healing by eliminating ROS, diminishing inflammation and promoting vessel formation. In full-thickness skin defect models of diabetic rats feet, the hydrogel promoted the healing of diabetic foot wounds at a rate of 2.4 fold. This hydrogel might offer a potential therapeutic option for DFUs. | |
2 | Stochastic Velocity Prediction for Connected Vehicles Considering V2V Communication Interruption | WANG Lihua | IEEE Transactions on Intelligent Transportation Systems | Reliable and accurate velocity prediction can significantly contribute to the quality of connected vehicle control applications. Existing efforts focus on the velocity prediction without considering vehicle-to-vehicle (V2V) communication interruption. Hence, a stochastic velocity prediction method for connected vehicles considering V2V communication interruption is put forward for the first time. The missing V2V commu-nication data are addressed by the piece-wise cubic Hermitespline interpolation. Then, the processed data are used as the input variables of the best conditional linear Gaussian (CLG)prediction model. Specifically, the best CLG model is obtained by analyzing the influence of different input variables on the velocity prediction without V2V communication interruption. The results demonstrate that the prediction accuracy of CLG-based model is acceptable if the communication interruption time is less than 5s compared to the non-interrupted V2V communication case. The sensitivity study of the best CLG model under multiple vehicles scenario indicates that choosing appropriate historical data substantially improve the prediction accuracy. Furthermore,the CLG-based predictor is proved to be an effective method to achieve higher prediction accuracy in two test road networks when compared with the Back-propagation and Long Short-Term Memory network. | |
3 | Research on high temperature wear resistance mechanism of CrN_CrAlN multilayer coatings | WANG Di | Tribology International | In this paper, a 16 μm CrN/CrAlN multilayer coating is prepared on the titanium alloy surface via arc ion plating. Since titanium alloys are susceptible to wear in a high-temperature environment, high-temperature wear per-formance and mechanism after coating are investigated. The results show that the friction coefficient of the CrN/ CrAlN multilayer coating decreases with an increase in temperature during wear tests at room temperature, 300 °C, 500 °C, and 700 °C. Moreover, the friction coefficient decreases from 0.9 at room temperature to 0.4 at 700 °C. The wear rate increases with the temperature, more specifically from 1.32 ×105 mm3/(N⋅m) at room temperature to 6.45 ×105 mm3/(N⋅m) at 700 °C. | |
4 | A study of the structure and erosion properties of CrNx_CrAlN coatings with different modulation periods | WANG Di | Wear | In this study, we deposited CrNx/CrAlN multilayer coatings with different modulation periods on TC4 titanium alloy substrates via cathodic arc deposition. The effects of the different modulation periods on the microstruc-ture, mechanical properties, erosion resistance, and fracture failure mechanism of the coatings were studied. The results show that the multilayer coatings exhibit a dense structure, with the CrNx layer being mainly composed of the CrN (200) and Cr2N (111) phases and the CrAlN layer being mainly composed of the CrN (111) and CrN (200) phases. The comprehensive mechanical properties of the multilayer coating with a modulation period of 200 nm are the best: The hardness is 3306 HV, the bonding force is 50.0 N, the crack propagation resistance is 483, the residual stress is the smallest, and the erosion resistance is the best. In the process of coating fracture failure, the CrAlN hard layer is mainly wear-resistant, while the CrNx metal-rich ductile layer mainly absorbs the fracture stress and undergoes a ductile–brittle transition, which eventually results in brittle fracture and layered peeling failure. | |
5 | Pollution characteristics and mixture risk prediction of phenolic environmental estrogens in rivers of the Beijing–Tianjin–Hebei urban agglomeration, China | LEI Kai | Science of The Total Environment | Phenolic environmental estrogens (PEEs) are ubiquitous in most rivers worldwide and may cause potential endocrine-disrupting effects in aquatic organisms. Three typical PEEs (bisphenol A, BPA; 4-tert-octylphenol,4-t-OP; and nonylphenol, NP) were investigated in the rivers of the Beijing–Tianjin–Hebeiurban agglomeration, which is the most urbanized and industrialized area in Northern China. The target PEEs were detected in 100% of river water samples, and the concentrations ranged from 23 to 255 ng L−1.The concentrations of NP in most river sections were higher than those of BPA and 4-t-OP. The spatio temporal variations in PEEs indicated that both domestic and industrial wastewater were main sources of PEEs in river water. In addition, rainfall runoff might be an important source of PEEs in the receiving waters, especially in the wet season. The eco-toxicological risk assessment of individual PEE revealed a moderate to high risk for aquatic organisms at most sampling sites. The mixture risk prediction based on the concentration addition method indicated a potential cumulative risk of PEEs in the study area, highlighting the importance of mixture risk assessment in the aquatic environment. | |
6 | Could phenological records from Chinese poems of the Tang and Song dynasties (618–1279 CE) be reliable evidence of past climate changes? | LIU Yachen | Climate of the Past | Phenological records in historical documents have been proven to be of unique value for reconstructing past climate changes. As a literary genre, poetry reached its peak in the Tang and Song dynasties (618–1279 CE) in China. Sources from this period could provide abundant phenological records in the absence of phenological observations.However, the reliability of phenological records from poems,as well as their processing methods, remains to be comprehensively summarized and discussed. In this paper, after introducing the certainties and uncertainties of phenological information in poems, the key processing steps and methods for deriving phenological records from poems and using them in past climate change studies are discussed: (1) two principles, namely the principle of conservatism and the principle of personal experience, should be followed to reduce uncertainties; (2) the phenological records in poems need to be filtered according to the types of poems, background information, rhetorical devices, spatial representations, and human influence; (3) animals and plants are identified at the species level according to their modern distributions and the sequences of different phenophases; (4) phenophases in poems are identified on the basis of modern observation criteria; (5) the dates and sites for the phenophases in poems are confirmed from background information and related studies.As a case study, 86 phenological records from poems of the Tang Dynasty in the Guanzhong region in China were extracted to reconstruct annual temperature anomalies in specific years in the period between 600 and 900 CE. Followingthis, the reconstruction from poems was compared with relevant reconstructions in published studies to demonstrate the validity and reliability of phenological records from poems in studies of past climate changes. This paper reveals that the phenological records from poems could be useful evidence of past climate changes after being scientifically processed.This could provide an important reference for future studies in this domain, in both principle and methodology, pursuant of extracting and applying phenological records from poems for larger areas and different periods in Chinese history. | |
7 | Operator algebras associated with multiplicative convolutions of arithmetic functions | DONG Aiju | SCIENCE CHINA Mathematics | The action of ℕ on l2(ℕ) is studied in association with the multiplicative structure of ℕ. Then the maximal ideal space of the Banach algebra generated by ℕ is homeomorphic to the product of closed unit disks indexed by primes, which reflects the fundamental theorem of arithmetic. The C*-algebra generated by ℕ does not contain any non-zero projection of finite rank. This assertion is equivalent to the existence of infinitely many primes. The von Neumann algebra generated by ℕ is B(l2(ℕ)), the set of all bounded operators on l2(ℕ). Moreover, the differential operator on l2(ℕ, 1/n(n+1)) defined by ∇f = μ * f is considered, where μ is the Möbius function. It is shown that the spectrum σ(∇) contains the closure of {ζ(s)-1: Re(s) > 1}. Interesting problems concerning ∇ are discussed. | |
8 | Structural Determination of Niobium-Doped Silicon Clusters by Far-infrared Spectroscopy and Theory | LI Xiaojun | Physical Chemistry Chemical Physics | In this work, the structures of cationic SinNb+(n= 4–12) clusters are determined using the combination of infrared multiple photon dissociation (IR-MPD) and density functional theory (DFT) calculations. The experimental IR-MPD spectra of the argon complexes of SinNb+are assigned by comparison to the calculated IR spectra of low-energy structures of SinNb+that are identified using the stochastic ‘random kick’ algorithm in conjunction with the BP86 GGA functional. It is found that the Nb dopant tends to bind in an apex position of the Sinframework forn= 4–9 and in surface positions with high coordinationnumbers forn= 10–12. For the larger doped clusters, it is suggested that multiple isomers coexist and contribute to the experimental spectra. The structural evolution of SinNb+clusters is similar to V-dopedsilicon clusters (J.Am.Chem.Soc., 2010,132, 15589–15602), except for the largest size investigated(n= 12), since V takes an endohedral position in Si12V+. The interaction with a Nb atom, with its partiallyunfilled 4d orbitals leads to a significant stability enhancement of the Sinframework as reflected,e.g.by high binding energies and large HOMO–LUMO gaps. | |
9 | Ag(I)-Coordinated Supramolecular Metallogels Based on Schiff Base | XUE Min | Crystal Growth & Design | Three Schiff base ligands containing two pyridine rings, S1, S2, and S3, show strong gelation abilities with AgNO3 in several pure or mixed solvents at room temperature. 1H NMR and Fourier transform infrared spectroscopy measurements not only demonstrated the coordination interaction between silver ion and nitrogen atom of the pyridine ring of the S2 ligand in S2-Ag metallogel, but also showed that hydrogen bonding contributes to the formation of the metallogels.In particular, S2-Ag metallogel shows a super smart and fully reversible thixotropic property, which has been rarely reported before in metallogels. X-ray diffraction(XRD) analysis revealed that S2-Ag metallogel in DMF takes a mixture of hexagonal and tetragonal packing modes. On the basis of the results of XRD and mass spectrometry analysis, a possible structure evolution process for the gel was proposed. And this model was further demonstrated by the results of polarizing microscopy and thermogravimetric analysis of S2-Ag metallogel. | |
