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The dispute over the effect of cavitation heat on material surface intensifies the fuzziness of cavitation erosion (CE) mechanism and limits the development of protective materials. Here, an anti-CE Al

Silicon is considered as an ideal anode material for the next generation of lithium-ion batteries (LIBs) owing to its high specific capacity, low lithiation potential, and high natural abundance. H...

The two-dimensional surfaces have been fueled by the infinite possibility they offered for basic research, and for novel technologies in nanoelectronics. To realize many of these promises, the effective strategies were to design and control their surface chemistry, which plays a vital role in determining the chemical and physical properties. Macrocyclic host–guest chemistry with the reversible noncovalent interactions between macrocyclic hosts and suitable guests can be readily used for constructing multifunctional surfaces. Macrocyclic pillararenes, possessed the unique structure, have attracted the attentions of researchers in recent years. This feature article covers the recent development of pillararene-based two-dimensional interfaces, including the fabrication and function of the hybrid composite. The combination of pillararenes and materials platform exhibited the novel property because of the characteristic of cavity of macrocyclic host and confined spaces of surfaces. We anticipate that this review will be helpful to the researchers working in the fields of supramolecular chemistry and materials science.

A simplefuro [2,3-d]pyrimidinone-based Schiff base FPS was synthesized via aza-Wittig reaction and structure elucidation was carried out by spectroscopic studies FT-IR, 1H NMR, and 13C NMR and mass spectrometry. FPS showed weak fluorescence emission in methanol and the selectivity of FPS to different metal ions (Mn2+, Ca2+, Fe2+, Fe3+, Mg2+, Al3+, Ba2+, Ag+, Co2+, Na+, K+, Cu2+, Zn2+, Pb2+, Bi3+) were studied by absorption and fluorescence titration. The results show that FPS has selective fluorescence sensing behavior for Zn2+ ions and the limit of detection (LOD) was calculated to be 1.19 × 10–8 mol/L. Moreover, FPS-Zn2+ acts as a metal based highly selective and sensitive new chemosensor for Cu2+ ions and the LOD was calculated to be 2.25 × 10–7 mol/L. In accordance with the results and theoretical calculations, we suspected that the binding mechanisms of FPS to Zn2+ and Cu2+ were assigned to be the cooperative interaction of Zn2+(Cu2+)-N.

To describe both the global and local characteristics of a network more comprehensively, we propose the weighted K-order propagation number (WKPN) algorithm to extract the disease propagation based on the network topology to evaluate the node importance. Each node is set as the source of infection, and the total number of infected nodes is defined as the K-order propagation number after experiencing the propagation time K. The simulation of the symmetric network with bridge nodes indicated that the WKPN algorithm was more effective for evaluation of the algorithm features. A deliberate attack strategy, which indicated an attack on the network according to the node importance from high to low, was employed to evaluate the WKPN algorithm in real networks. Compared with the other methods tested, the results demonstrate the applicability and advancement that a lower number of nodes, with a higher importance calculated by the K-order propagation number algorithm, has to achieve full damage to the network structure.

In the life system, the biointerface plays an important role in cell adsorption, platelet adsorption and activation. Therefore, the study of protein adsorption on the biointerface is of great significance for understanding life phenomena and treatment in vitro. In this paper, a chiral biointerface was constructed by the virtue of host-guest interaction between a water-soluble pillar[5]arene (WP5) and phenethylamine (PEA) over a gold surface for adsorption of lysozyme proteins. From the experimental results it was identified that the host-guest biointerface has a high adsorption capacity and strong chiral selectivity. Furthermotre, it was identified that the host-guest interaction plays the decisive role in the enhancement of chirality of the interface, which was much beneficial for increasing protein adsorption and amplifying the capacity of chiral discrimination. Therefore, this work provides a new idea for the construction of biointerface materials with high protein adsorption capacity and high chiral selectivity through supramolecular interaction, which will have potential applications in the fields of biosensors, biocatalysts, biomaterials.

Inspired by glucose-sensitive ion channels, herein we describe a biomimetic glucose-enantiomer-driven ion gate via the introduction of the chiral pillar[6]arene-based host–guest systems into the artificial nanochannels. The chiral nanochannels show a high chiral-driven ionic gate for glucose enantiomers and can be switched “off” by d-glucose and be switched “on” by l-glucose. Remarkably, the chiral nanochannel also exhibited a good reversibility toward glucose enantiomers. Further research indicates that the switching behaviors differed due to the differences in binding strength between chiral pillar[6]arene and glucose enantiomers, which can lead to the different surface charge within nanochannel. Given these promising results, the studies of chiral-driven ion gates may not only give interesting insight for the research of biological and pathological processes caused by glucose-sensitive ion channels, but also help to understand the origin of the high stereoselectivity in life systems., Uptake and release of glucose is regulated by glucose-sensitive ion channels, but complexity of the system impedes investigation of the gating behavior under physiological conditions. Here the authors use a pillararene based artificial ion channel to mimic and investigate chirality driven switching of a glucose ion channel.

Modulating protein selective translocation is a significant process, which has great potential for mimicking and understanding complex biological activities. As such, how to construct a nanochannel that can accomplish well gating protein transport is vital and challenge. Herein, inspired by nature, we presented a robust strategy to construct a switchable nanochannel by introducing a pH responsive binary host-guest system into a nanochannel. Benefiting from the novel design of the pillar[5]arene as gatekeeper, the functional nanochannel can well facilitate histone transport. Under pH regulation, the host-guest assembled nanochannel is capable of switching "on" and "off" to manipulate the histone translocation process. This study exemplifies the importance of molecular switch mediated protein transport in this process and provides a new theoretical model for biological research, which will open a new avenue for better understanding of some physiological and pathological behaviors.

Hierarchically structured polymer fibers encompassing 1-D, 2-D, and 3-D structures with at least one dimension nano- to micro-meters in size have recently received an increasing amount of attention due to their vast potential in such applications as sensing, medicine, energy storage. This review summarizes advancements in the last ten years in the design and fabrication of hierarchically structured polymer fibers via electrospinning technologies, including a diversity of electrospinning devices and electrospinning parameters using various polymers. These well-defined, multilevel structures enable the fibers to be used more effectively in applications in the biomedical field, such as drug delivery, tissue engineering, and diagnostics. This review can provide a better understanding of the relationships between the structure and functionality of polymer fibers for further biomedical applications.

The capability of short message service (SMS) of Beidou navigation system (BDS) is an advantage over the GPS. Text-only SMS hinders the applicability of BDS. The global voice chat has been designed & tested over the BDS SMS, which can transmit voices of 2 seconds in a single 78-byte message. Field tests have been completed between two sites far apart over 2,500 km, one in the city of Xi'an and the other onboard a ship in the South China Sea. Results have shown that the voice chat over the BDS SMS is available to any subscriber even he cannot type a single word. More than 90% of interaction time is saved and authentication security is enhanced. The global voice chat is an effective supplement to the outdoor emergency communication systems nowadays.

The self-assembly of macroscopic droplets on interfaces has attracted much attention and shown promising potential in the field of materials as a sensing or delivery system. Herein, we reported a new strategy to construct a d-tartaric acid-functionalized pillar[5]arene (d-TP5) interface for macroscopic differentiation of histidine enantiomers. At the molecular level, it has been proved that d-TP5 has the ability to distinguish between l-Histidine and d-Histidine ( KL/ KD = 4.6). Furthermore, a functional d-TP5 surface was constructed by a click reaction and characterized by contact angle measurements and attenuated total reflection-Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy analyses. The d-TP5 surface exhibited the selective dynamic adhesion of l-His droplets on the tilted interface. It means that a d-TP5 surface can distinguish histidine enantiomers at a macrolevel. The amount of d/l-His absorbed by a d-TP5 surface and the morphology of His particles formed by removing the solvent have been investigated to prove that the self-assembly of His occurs on the d-TP5 surface. The possible mechanism has been discussed from host-guest interaction and chiral recognition. The proposed chiral material displays rapidly remarkable selectivity and is convenient to be utilized, which should be suitable for comprehending chiral recognition processing and applied to chiral recognition detection of histidine in a living body.

Populations of marine fishes are show relatively weak genetic differentiation due to the lack of geographical barriers and the potential for the strong diffusion ability favoring high levels of gene flow. The large yellow croaker (Larimichthys crocea) is a commercially important fish species with high gene flow, and its aquaculture production ranks first among all marine fishes cultured in China. To better understand the population structure of L. crocea, a total of 7161 quality-filtered SNP markers were identified in 120 individuals from five farmed and wild populations by using restriction site-associated DNA sequencing (RAD-seq). Our population genetic inferences suggest the existence of two genetic lineages of this croaker in the wild populations in the coastal waters of China. We suggested that an allopatric speciation mechanism is typically characterized by the formation of the Taiwan Strait between the South and East China Sea. The farmed and wild populations present in Ningde City exhibit similar genetic ancestry, which implies that the latter population may represent escaped farmed fish with a higher discharge frequency, rather than areal wild population.

N-acetylglucosamine analogues exist in nature as an important saccharide in human body and can regulate a variety of life activities captured through biological nanochannels. Herein we describe a biomimetic strategy via supramolecular host-guest chemistry for constructing artificial nanochannels to detect N-acetylglucosamine analogues. The functional nanochannels exhibited a high selectivity and good reversibility towards N-acetylglucosamine. Further studies indicate that the detecting behaviors was probably due to the multiple hydrogen bonding interactions and an appropriately fitting the functional and geometric requirements between the tryptophan-decorated pillararenes and N-acetylglucosamine, leading to the change of the surface charge and wettability within the nanochannels. These studies can give interesting insight for the research of biological processes caused by N-acetylglucosamine-sensitive ion channels, and also help to develop the platform for detecting N-acetylglucosamine in vitro.

Aiming at the problem of intelligent detection and location of marine VHF radio station fault machine,this paper studies BP neural network algorithm, analyzes the characteristics of VHF radio stations at sea,builds fault tree model, presents an intelligent detection method of VHF radio fault using L-M (Levenberg-Marquardt) intelligent algorithm to design L-M algorithm-based automatic fault detection model for VHF stations. The feasibility and efficiency of L-M algorithm in VHF fault detection are verified by simulation. The results show that: L-M algorithm can identify fault points more quickly and accurately among VHF radio station fault detection methods. Compared with the traditional manual detection, accuracy and efficiency of L-M algorithm are greatly improved.

Multiple drug resistance (MDR) of cancer cells is a major cause of chemotherapy failure. It is currently a great challenge to develop a direct and effective strategy for continuously inhibiting the P-glycoprotein (P-gp) drug pump of MDR tumor cells, thus enhancing the intracellular concentration of the therapeutic agent for effectively killing MDR tumor cells. Here, a new implantable hierarchical-structured ultrafine fiber device is developed via a microfluidic-electrospinning technology for localized codelivery of doxorubicin (DOX) and apatinib (AP). An extremely high encapsulation efficiency of ≈99% for the dual drugs is achieved through this strategy. The release of the loaded dual drugs can be controlled in a programmable release model with a rapid release of the micelles, while AP is slowly released. The sustained release of AP can continuously inhibit the P-gp drug pump of MDR tumor cells, increasing the intracellular DOX accumulation. The in vivo DOX biodistribution displays that the DOX accumulation in the tumor tissues achieves 17.82% after implanting the fiber device for 72 h, which is 6.36-fold higher than that of the intravenously injected DOX. Importantly, the fiber device shows an excellent antitumor effect on MDR tumor-bearing mice with low systemic toxicity.

Mixed excitation linear prediction (MELP) algorithm has good characteristics of high voice compression rate and optimize the quality of synthesized speech, the design of MELP vocoder voice communication system based on Beidou vocoder, this system mainly focuses on speech compression encoding MELP algorithm, firstly establish the channel model, the original speech feature parameters obtained by MELP encoding algorithm combining decoding algorithm and realize the reduction of synthetic speech, speech compression rate to 300bps algorithm, and combined with the Beidou communication protocol and the function design, realization of Beidou voice data communication function. The experimental data show that the very low bit rate speech compression algorithm is effective in Beidou data voice communication, and has high practical value.

In recent years, calixarene-based fluorescent chemosensors for mercury(II) are mushroom growth because of its intrinsic sensitivity. The design of the highly selective calixarene-based chemosensors towards mercury(II) is still a challenging task. In this paper, the progress of highly selective fluorescent sensor for mercury(II) based on calixarene derivatives is reviewed according to a mono-fluorophore chemosensor and a bi-fluorophore chemosensor. Some new developments such as calixarene-modified nanoparticles are also covered.

The light-controlled gating of ion transport across membranes is central to nature (e.g., in protein channels). Herein, inspired by channelrhodopsins, we introduce a facile non-covalent approach towards light-responsive biomimetic channelrhodopsin nanochannels using host–guest interactions between a negative pillararene host and a positive azobenzene guest. By switching between threading and dethreading states with alternating visible and UV light irradiation, the functional channels can be flexible to regulate the inner surface charge of the channels, which in turn was exploited to achieve different forms of ion transport, for instance, cation-selective transport and anion-selective transport. Additionally, the pillararene-azobenzene-based nanochannel system could be used to construct a light-activated valve for molecular transport. Given these promising results, we suggest that this system could not only provide a better understanding of some biological processes, but also be applied for drug delivery and various biotechnological applications., Light-controlled gating of ion transport across membranes occurs in nature via channelrhodopsin nanochannels. Here, the authors show facile non-covalent approach towards light-responsive biomimetic nanochannels using host–guest interactions between a negative pillararene host and a positive azobenzene guest.

A robust and efficient object tracking algorithm is required in a variety of computer vision applications. Although various modern trackers have impressive performance, some challenges such as occlusion and target scale variation are still intractable, especially in the complex scenarios. This paper proposes a robust scale adaptive tracking algorithm to predict target scale by a sequential Monte Carlo method and determine the target location by the correlation filter simultaneously. By analyzing the response map of the target region, the completeness of the target can be measured by the peak-to-sidelobe rate (PSR), i.e., the lower the PSR, the more likely the target is being occluded. A strict template update strategy is designed to accommodate the appearance change and avoid template corruption. If the occlusion occurs, a retained scheme is allowed and the tracker refrains from drifting away. Additionally, the feature integration is incorporated to guarantee the robustness of the proposed approach. The experimental results show that our method outperforms other state-of-the-art trackers in terms of both the distance precision and overlap precision on the publicly available TB-50 dataset.

Liquid quantum dots (QDs) have been used as a fluorescent films sensor. Constructing a macroscopic, responsive, liquid QD system for lysine (Lys) is a challenging task. To achieve a selective macroscopic response towards Lys, herein we present a new strategy for integrating host-guest chemistry into a liquid QD system. Water-soluble pillar[5]arene WP5 was designed and synthesized as a host. WP5 was introduced onto the surface of PEG1810-modified QDs by host-guest interactions to obtain liquid WP5-1810-QDs. The interaction between WP5 and Lys is stronger than that between WP5 and PEG-1810, causing WP5 to be released from the 1810-QDs surface in the presence of Lys, resulting in macroscopic fluorescence quenching. This smart material shows promise in amino acid sensing and separation.

Molecular switch systems, having been extensively studied in the solution phase, have the ability to perform with good controllability and rapid-responsiveness, making them ideally suited for the design of molecular devices for drug delivery, and information or sensing functions. Inspired by a wide range of objects with visual changes, like Mimosa pudica towards external stimuli, in order to understand molecular switches well, they must be interfaced with the macroscopic world so that they can be directly realized by visual detectable changes even observed by the naked eye. This can be critical for fabricating intelligent microfluidics and laboratory-on-chip devices, that may have wide applications in the fields of biology and materials science. But to realize this objective, especially for fabricating macroscopic surface switches, unveiling host–guest weak interactions to achieve visual phenomena is still the greatest thrill. Thankfully, surface contact angles provide us with a wonderful method to further investigate the microscopic origin of the macroscopic changes. Therefore, interfacial modification becomes a paramount process. Macrocyclic compounds, encompassing an innovative concept to deal with reversible noncovalent interactions between macrocyclic hosts and suitable guests, are good candidates for surface functionalization. In this feature article, we discuss recent developments in macroscopic contact angle switches formed by different macrocyclic hosts and highlight the properties of these new functional surfaces and their potential applications.

Molecular switch systems, having been extensively studied in the solution phase, have the ability to perform with good controllability and rapid-responsiveness, making them ideally suited for the design of molecular devices for drug delivery, and information or sensing functions. Inspired by a wide range of objects with visual changes, like Mimosa pudica towards external stimuli, in order to understand molecular switches well, they must be interfaced with the macroscopic world so that they can be directly realized by visual detectable changes even observed by the naked eye. This can be critical for fabricating intelligent microfluidics and laboratory-on-chip devices, that may have wide applications in the fields of biology and materials science. But to realize this objective, especially for fabricating macroscopic surface switches, unveiling host–guest weak interactions to achieve visual phenomena is still the greatest thrill. Thankfully, surface contact angles provide us with a wonderful method to further investigate the microscopic origin of the macroscopic changes. Therefore, interfacial modification becomes a paramount process. Macrocyclic compounds, encompassing an innovative concept to deal with reversible noncovalent interactions between macrocyclic hosts and suitable guests, are good candidates for surface functionalization. In this feature article, we discuss recent developments in macroscopic contact angle switches formed by different macrocyclic hosts and highlight the properties of these new functional surfaces and their potential applications.