单宁酸仿生修饰及多元胺可控接枝表面改性超高分子量聚乙烯纤维

首先利用单宁酸-金属离子络合物对超高分子量聚乙烯(UHMWPE)纤维进行表面涂覆改性,在纤维表面引入单宁酸,进而以单宁酸为过渡层,利用氰尿酰氯和间苯二胺进行可控接枝,从而引入氨基基团,以提高纤维与树脂间的结合力。结果表明,UHMWPE纤维表面可控接枝大量氨基官能团,纤维表面粗糙度明显增加,纤维与树脂之间的界面剪切强度增强,其中接枝次数为3次后的UHMWPE纤维与环氧树脂界面剪切强度达到1.40 MPa,与原始纤维相比较提高了89.98%。

pH敏感性智能水凝胶的设计及其应用

水凝胶是一种交联的三维网状亲水性聚合物材料,具有与生物组织相似的特点并且能够吸收大量的水分。作为智能水凝胶的一种,pH敏感性水凝胶因其结构中含有大量碱性或酸性基团从而具有一定的pH敏感性。凭借这些特性,近年来pH敏感性水凝胶在生物、医学、物理、环境、纺织等众多研究领域备受关注。本文围绕pH敏感性水凝胶的响应机制、分类以及应用三个方面进行综述。在响应机制上,本文从响应过程、影响因素和溶胀扩散模型三方面进行综述;在分类上,根据水凝胶敏感性的不同分为溶胀-收缩类和溶胶-凝胶类两类,并进一步根据pH作用范围的不同将溶胀-收缩类细分为阴离子类、阳离子类以及两性离子类,溶胀-收缩类细分为硼酸酯类、酰腙类以及亚胺类;在应用研究上,本文总结了其在医学、环境、生物、智能检测、功能材料等热门领域的研究情况。最后,对pH敏感性水凝胶的未来的发展方向进行了展望。

Oblique angle deposition and its applications in plasmonics

Plasmonics based on localized surface plasmon resonance （LSPR） has found many exciting appli- cations recently. Those applications usually require a good morphological and structural control of metallic nanostructures. Oblique angle deposition （OAD） has been demonstrated as a powerful technique for various plasmonic applications due to its advantages in controlling the size, shape, and composition of metallic nanostructures. In this review, we focus on the fabrication of metallic nanostructures by OAD and their applications in plasmonics. After a brief introduction to OAD technique, recent progress of applying OAD in fabricating noble metallic nanostructures for LSPR sensing, surface-enhanced Raman scattering, surface-enhanced infrared absorption, metal-enhanced fluorescence, and metamaterials, and their corresponding properties are reviewed. The future requirements for OAD plasmonics applications are also discussed.

In-chain functionalization through the combination of ring opening copolymerization and oxime "Click" reaction towards X-ray opaque polylactide copolymers

X-ray imaging functionalization of biodegradable polyesters is a great demand and challenge in biomedical applications.In this work,a strategy of in-chain functionalization through the combination of ring opening copolymerization and oxime "Click" postfunctionalization was developed towards X-ray opaque polylactide copolymers.A functionalized cyclic carbonate was first synthesized and used as comonomer of polylactide copolymers,which were subjected to postfunctionalization of oxime "Click" reaction towards iodinated polylactide copolymers.The chemical structure and physical properties of the target products were traced and confirmed.In vitro cytotoxicity evaluation with 3T3-Swiss albino by Alamar blue demonstrated a low cytotoxicity.The X-ray radiopacity was analyzed by Micro-CT and quantified by Hounsfield Units value,which could be tailorable by the feedstock.It is a promising X-ray visible implantable biomaterial in biomedical applications.

MyWAL:performance optimization by removing redundant input/output stack in key-value store

Based on a log-structured merge(LSM)tree,the key-value(KV)storage system can provide high reading performance and optimize random writing performance.It is widely used in modern data storage systems like e-commerce,online analytics,and real-time communication.An LSM tree stores new KV data in the memory and flushes to disk in batches.To prevent data loss in memory if there is an unexpected crash,RocksDB appends updating data in the write-ahead log(WAL)before updating the memory.However,synchronous WAL significantly reduces writing performance.In this paper,we present a new WAL mechanism named MyWAL.It directly manages raw devices(or partitions)instead of saving data on a traditional file system.These can avoid useless metadata updating and write data sequentially on disks.Experimental results show that MyWAL can significantly improve the data writing performance of RocksDB compared to the traditional WAL for small KV data on solid-state disks(SSDs),as much as five to eight times faster.On non-volatile memory express soild-state drives(NVMe SSDs)and non-volatile memory(NVM),MyWAL can improve data writing performance by 10%–30%.Furthermore,the results of YCSB(Yahoo!Cloud Serving Benchmark)show that the latency decreased by 50%compared with SpanDB.

Inherently radiopaque polyurethane beads as potential multifunctional embolic agent in hepatocellular carcinoma therapy

The aim of the current study is to report an inherently radiopaque drug-eluted beads(DEBs)as promising embolic materials for TACE techniques.Firstly,the synthesized radiopaque iodinated polycaprolactonepolyurethanes(I-PCLUs)are synthesized by chain-extending method by using 4,4-′isopropylidinedi-(2,6-diiodophenol)(IBPA)as the radiopacifying agent.Then,doxorubicin(Dox)is introduced as a chemotherapeutic agent into I-PCLU beads via a double emulsification(W/O/W)method.The drug loading and controlled release behavior of two ratios of I-PCLU/Dox are found to be dependent upon the internal porous microstructure,and the radiopacity is well-retained after four weeks drug release.Besides,the I-PCLU/Dox beads exhibit positive in vitro anti-tumor effect.The in vivo intramuscular implantation and liver embolization results demonstrate that I-PCLU beads have good histocompatibility,occlusion effect and X-ray traceability.Furthermore,the drug-loaded I-PCLU beads are performed into a VX2 rabbit hepatocellular carcinoma(HCC)model using a micro-catheter,form embolization of hepatic arteries and inhibit the tumor growth after one week post-injection.Hence,this polymeric system provides a potential radiopaque chemoembolization candidate for HCC and other cancer therapies,which could bring opportunities to the next generation of multifunctional embolic agents.

Legumain-induced intracerebrally crosslinked vesicles for suppressing efflux transport of Alzheimer’s disease multi-drug nanosystem

Brain barrier is both a protective permeability hurdle and a limitation site where therapeutic agents are excluded to enter the target region.Designing drug vehicle to overcome this notorious barrier bottle is challenging.Herein,we construct a stimuli-responsive self-assembled nanovesicle that delivers water-soluble drugs to prevent the efflux transport of brain barriers by responding to the endogenously occurring signals in Alzheimer’s disease(AD)brain microenvironment.Once stimuli-responsive vesicles are accumulated in intracerebrally,the intrinsically occurring legumain endopeptidase cleaves the Ac-Ala-Ala-Asn-Cys-Asp(AK)short peptide on the drug vesicles to expose the 1,2 thiol amino group to cyclize with the cyano groups on 2-cyano-6-aminobenzothiazole(CABT)of the chaperone vesicles,thus triggering the formation of cross-linked micrometre-scale vesicles.Such a structural alteration completely prevents further brain barriers efflux.The superior neuroprotective capacity of cross-linked vesicles is validated in senescence accelerated mouse prone 8(SAMP8).This smart multi-drug delivery vesicle is promising to serve as a powerful system for AD treatment and can be adapted for the therapy of other central nervous system(CNS)disorders.

IRF7 and CTSS are pivotal for cutaneous wound healing and may serve as therapeutic targets

Dear Editor,Adult cutaneous wounds typically result in deficient regenera-tion due to abnormal fibro-proliferative responses.1 The scarring,while conducive to preventing extended infection and loss of nutrients at the injury site,can be troublesome.2 In contrast,wound healing in embryos showes lower levels of inflammation and a remarkable capacity for remodeling.3 Interestingly,the capability of fetal scarless healing is age-dependent.As contrasted with the near-normal healing after the injury that occurs in the early gestational period(embryonic day 16,E16),wound healing in late gestation(embryonic day 18,E18)has prominent fibrosis.The mechanisms responsible for this transition are largely unknown.