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Brain-inspired computing is an emerging field, which intends to extend the capabilities of information technology beyond digital logic. The progress of the field relies on artificial synaptic devices as the building block for brainlike computing systems. Here, we report an electronic synapse based on a ferroelectric tunnel memristor, where its synaptic plasticity learning property can be controlled by nanoscale interface engineering. The effect of the interface engineering on the device performance was studied. Different memristor interfaces lead to an opposite virgin resistance state of the devices. More importantly, nanoscale interface engineering could tune the intrinsic band alignment of the ferroelectric/metal-semiconductor heterostructure over a large range of 1.28 eV, which eventually results in different memristive and spike-timing-dependent plasticity (STDP) properties of the devices. Bidirectional and unidirectional gradual resistance modulation of the devices could therefore be controlled by tuning the band alignment. This study gives useful insights on tuning device functionalities through nanoscale interface engineering. The diverse STDP forms of the memristors with different interfaces may play different specific roles in various spike neural networks.

Traffic signal control is widely used at intersection to improve its operation efficiency. However, the existing signal control systems cannot satisfy the control requirements under unsaturated, saturated, and oversaturated conditions, which will induce queue spillover, even network deadlock. A signal Cooperative Control method with traffic Supply and Demand (CCSD) on a single intersection is put forward to maximize the efficiency and avoid queue spillover by the cooperation between traffic supply and demand. A general CCSD control framework is constructed by the control relationship description and discrete-time state-space equations. Furthermore, the uniform matrix description of CCSD is put forward under the framework to fast solve the problem by matrix calculation. An artificial intelligence planning model on CCSD is established by an objective function compromising between throughput and fairness to satisfy the control requirements under dynamic unknown traffic environment. CCSD is compared with the Webster method and capacity-aware back-pressure (CABP) control in the experiments by both the simulation data and investigation data under unsaturated, saturated, and oversaturated conditions. The results show that CCSD is superior to CABP control and the Webster method in the throughput, the number of stops, and stop time, and can avoid the queue spillover. Accordingly, CCSD can be used to improve the efficiency and avoid queue spillover at intersection under all traffic conditions.

Arsenite (As(III)) is more toxic and difficult to remove than arsenate (As(V)). In this study, an S-doped Cu-La bimetallic oxide (S-CuLaO) decorated with metal-organic framework (MOF) composite (S-CuLaO@UIO-66) was synthesized and applied for the adsorption of As(III). The maximum adsorption capacity of As(III) by S-CuLaO@UIO-66 was as high as 171 mg/g, which was much higher compared with other MOF compounds reported to date. The UIO-66 support improved the dispersion and reduced the size of the S-CuLaO particles, which increased the number of exposed adsorption reactive sites. Study of the mechanism revealed that the synchronous oxidation and adsorption significantly increased the removal of As(III). O2∙- was produced by the receiving electron from the dissolved oxygen from Cu(I) in S-CuLaO, which converted As(III) to As(V). Furthermore, the stability and reusability S-CuLaO@UIO-66 (without regeneration) was investigated at a low As(III) concentration (approximately 1000 µg/L) in deionized water and well water. The residual arsenic concentration ranged from 0.8 to 2.8 μg/L in deionized water and 3–58.2 μg/L in well water within 240 min during three cycles. Generally, this study suggests that combining an optimal oxide with a stable MOF is a promising approach for the fabrication of composite adsorbents.

Nonvolatile stateful logic through RRAM is a promising route to build in-memory computing architecture. In this letter, a logic methodology based on 1T1R structure has been proposed to implement functionally complete Boolean logics. Arbitrary logic functions could be realized in two steps: initialization and writing. An additional read step is required to read out the logic result, which is in situ stored in the nonvolatile resistive state of the memory. Cascade problem in building larger logic circuits is also discussed. Our 1T1R logic device and operation method could be beneficial for massive integration and practical application of RRAM-based logic.

Resistive random access memory (RRAM) based reconfigurable logic provides a temporal programmable dimension to realize Boolean logic functions and is regarded as a promising route to build non-von Neumann computing architecture. In this work, a reconfigurable operation method is proposed to perform nonvolatile sequential logic in a HfO2-based RRAM array. Eight kinds of Boolean logic functions can be implemented within the same hardware fabrics. During the logic computing processes, the RRAM devices in an array are flexibly configured in a bipolar or complementary structure. The validity was demonstrated by experimentally implemented NAND and XOR logic functions and a theoretically designed 1-bit full adder. With the trade-off between temporal and spatial computing complexity, our method makes better use of limited computing resources, thus provides an attractive scheme for the construction of logic-in-memory systems.

Nonvolatile stateful logic computing in memristors is a promising paradigm with which to realize the unity of information storage and processing in the same physical location that has shown great feasibility for breaking the von Neumann bottleneck in traditional computing architecture. How to reduce the computational complexity of memristor-based logic functions is a matter of concern. Here, based on a general logic expression, we proposed a method to implement the arbitrary logic of complete 16 Boolean logic in two steps with one memristor in the crossbar architecture. A representative functional complete NAND logic is successfully experimentally demonstrated in the filamentary Ag-AgGeTe-Ta memristors to prove the validity of our method. We believe our work may promote the development of the revolutionary logic in memory architectures.

Owing to the capability of integrating the information storage and computing in the same physical location, in-memory computing with memristors has become a research hotspot as a promising route for non von Neumann architecture. However, it is still a challenge to develop high performance devices as well as optimized logic methodologies to realize energy-efficient computing. Herein, filamentary Cu/GeTe/TiN memristor is reported to show satisfactory properties with nanosecond switching speed ( 104 cycles) and good retention (>104 s @85 °C). It is revealed that the charge carrier conduction mechanisms in high resistance and low resistance states are Schottky emission and hopping transport between the adjacent Cu clusters, respectively, based on the analysis of current-voltage behaviors and resistance-temperature characteristics. An intuitive picture is given to describe the dynamic processes of resistive switching. Moreover, based on the basic material implication (IMP) logic circuit, we proposed a reconfigurable logic method and experimentally implemented IMP, NOT, OR, and COPY logic functions. Design of a one-bit full adder with reduction in computational sequences and its validation in simulation further demonstrate the potential practical application. The results provide important progress towards understanding of resistive switching mechanism and realization of energy-efficient in-memory computing architecture.

RRAM is a promising candidate to construct in-memory computing architecture which can break through the von Neumann bottleneck. Taking advantage of the CMOS compatible 1T1R RRAM, functionally complete Boolean logics can be realized within two steps in a single unit that can suppress sneak pass problem and avoid cascading problem partially. In addition, an 8-bit pre- calculation adder with low computation complexity is designed and demonstrated experimentally to verify the feasibility and efficiency of 1T1R based in-memory computing architecture, which is applicable to future energy-efficient information processing systems.

Resistive random access memory (RRAM) based reconfigurable logic provides a temporal programmable dimension to realize Boolean logic functions and is regarded as a promising route to build non-von Neumann computing architecture. In this work, a reconfigurable operation method is proposed to perform nonvolatile sequential logic in a HfO

Memristive stateful logic has emerged as a promising next-generation in-memory computing paradigm to address escalating computing-performance pressures in traditional von Neumann architecture. Here, we present a nonvolatile reprogrammable logic method that can process data between different rows and columns in a memristive crossbar array based on material implication (IMP) logic. Arbitrary Boolean logic can be executed with a reprogrammable cell containing four memristors in a crossbar array. In the fabricated Ti/HfO2/W memristive array, some fundamental functions, such as universal NAND logic and data transfer, were experimentally implemented. Moreover, using eight memristors in a 2 × 4 array, a one-bit full adder was theoretically designed and verified by simulation to exhibit the feasibility of our method to accomplish complex computing tasks. In addition, some critical logic-related performances were further discussed, such as the flexibility of data processing, cascading problem and bit error rate. Such a method could be a step forward in developing IMP-based memristive nonvolatile logic for large-scale in-memory computing architecture.

Memristors are attracting considerable interest for their prospective applications in nonvolatile memory, neuromorphic computing, and in-memory computing. However, the nature of resistance switching is still under debate, and current fluctuation in memristors is one of the critical concerns for stable performance. In this work, random telegraph noise (RTN) as the indication of current instabilities in distinct resistance states of the Pt/Ti/HfO2/W memristor is thoroughly investigated. Standard two-level digital-like RTN, multilevel current instabilities with non-correlation/correlation defects, and irreversible current transitions are observed and analyzed. The dependence of RTN on the resistance and read bias reveals that the current fluctuation depends strongly on the morphology and evolution of the conductive filament composed of oxygen vacancies. Our results link the current fluctuation behaviors to the evolution of the conductive filament and will guide continuous optimization of memristive devices.

A sulfone-functionalized metal-organic framework (MOF), USTC-253, has been synthesized that exhibits a much higher CO2 uptake capacity (168-182 %) than the corresponding unfurnished MOFs. The introduction of trifluoroacetic acid (TFA) during the synthesis of USTC-253 affords defect-containing USTC-253-TFA with exposed metal centers, which has an increased CO2 uptake (167 %) compared to pristine USTC-253. USTC-253-TFA exhibits a very high ideal adsorption solution theory selectivity (S=75) to CO2 over N2 at 298 K. In addition, USTC-253-TFA demonstrates good catalytic activity and recyclability in the cycloaddition of CO2 and epoxide at room temperature under 1 bar CO2 pressure as a result of the presence of Lewis and Bronsted acid sites, which were evaluated by diffuse reflectance infrared Fourier transform spectroscopy with a CO probe molecule. We propose that the CO2 adsorption capability has a positive correlation with the catalytic performance toward CO2 conversion.

For the remediation of oil spills and organic solvent leakage into water, it is desirable to develop not only advanced sorbents with a high adsorption capability but also labor- and time-saving apparatuses that can work continuously without human intervention. In this work, we synthesized a novel and highly stable porous coordination polymer (PCP, also called metal-organic framework), University of Science and Technology of China-6 (USTC-6), with a corrugated -CF3 surface that features high hydrophobicity. The uniform growth of USTC-6 throughout a graphene oxide (GO)-modified sponge was achieved and yielded a macroscopic USTC-6@GO@sponge sorbent, which repels water and exhibits a superior adsorption capacity for diverse oils and organic solvents. Remarkably, the sorbent can be further assembled with tubes and a self-priming pump to build a model apparatus that affords consecutive and efficient oil recovery from water. The easy and fast recovery of oils/organic solvents from water based on such an apparatus indicates that it has great potential for future water purification and treatment. A non-stick coordination polymer coating helps sponges absorb and recover up to 40 times their own weight in oil under extreme temperatures. Using passive sorbents to clean up toxic spills normally requires specially engineered materials, such as biomimetic surfaces with nanoscale rough features, to repel water molecules and attract oil particles. Now, Hai-Long Jiang from the University of Science and Technology of China and co-workers have developed a way to achieve these properties using porous coordination polymers containing copper ions and fluorinated organic ligands. After dipping a commercial sponge in graphene oxide to enhance copper binding, the team grew their coordination polymer coating in situ and found it yielded a corrugated surface with high hydrophobicity. Intriguingly, a prototype assembled from the coated sponge and a self-priming pump enabled labor-free cleanup of oil spills from water. A hydrophobic porous coordination polymer (PCP) has been synthesized and its growth throughout the graphene oxide (GO)-modified sponge yields a macroscopic PCP@GO@sponge sorbent, which repels water and exhibits superior adsorption for diverse oils. Remarkably, the sorbent is further assembled with tubes and a self-priming pump to build a model apparatus that can afford consecutive and efficient oil recovery from water.

To observe the expression of receptor activator of NF-κB ligand (RANKL) and its decoy receptor osteoprotegerin (OPG) during unloading period of dental implants.An animal model of dental implants was established in Beagle dogs. Bone remodeling was tested at 3, 7, 15, 30, 60 and 90 days after the placement of implants. RANKL and OPG mRNA expression were quantified by real-time PCR. Then mandibular bones were resected and some sections were observed.The most prominent period of bone remodeling occurred at 7 day after the placement of implants (OPG/RANKL mRNA, 2.15 ± 0.1). The expression of RANKL and OPG increased in a time-dependent manner in both soft and hard tissue. After 7 days they gradually decreased.Both OPG and RANKL were expressed in peri-implant tissues, and the changing tendency of RANKL and OPGmRNA was consistent with the change of bone remodeling. The active stage for bone remodelling in peri-implant tissues during unloading period is about 7 days after implantation.

Laccase is a copper-containing polyphenol oxidase that has great potential in industrial and biotechnological applications. Previous research has suggested that fungal laccase may be involved in the defense against oxidative stress, but there is little direct evidence supporting this hypothesis, and the mechanism by which laccase protects cells from oxidative stress also remains unclear. Here, we report that the expression of the laccase gene from white rot fungus in Pichia pastoris can significantly enhance the resistance of yeast to H(2)O(2)-mediated oxidative stress. The expression of laccase in yeast was found to confer a strong ability to scavenge intracellular H(2)O(2) and to protect cells from lipid oxidative damage. The mechanism by which laccase gene expression increases resistance to oxidative stress was then investigated further. We found that laccase gene expression in Pichia pastoris could increase the level of glutathione-based antioxidative activity, including the intracellular glutathione levels and the enzymatic activity of glutathione peroxidase, glutathione reductase, and γ-glutamylcysteine synthetase. The transcription of the laccase gene in Pichia pastoris was found to be enhanced by the oxidative stress caused by exogenous H(2)O(2). The stimulation of laccase gene expression in response to exogenous H(2)O(2) stress further contributed to the transcriptional induction of the genes involved in the glutathione-dependent antioxidative system, including PpYAP1, PpGPX1, PpPMP20, PpGLR1, and PpGSH1. Taken together, these results suggest that the expression of the laccase gene in Pichia pastoris can enhance the resistance of yeast to H(2)O(2)-mediated oxidative stress by stimulating the glutathione-based antioxidative system to protect the cell from oxidative damage.

To evaluate the clinical effectiveness and the satisfaction on aesthetic effectiveness of application of guided bone regeneration (GBR) technique in maxillary lateral incisor implant site.Ninety patients were selected who only lost maxillary lateral incisor and placed with 101 implants(the implant systems were 3i, Osstem, ITI, Ankylos, BLB). The final restorations were porcelain-fused-to-metal crowns. Clinical and X-ray examinations were conducted and esthetic results were observed at 3, 6,12 months after dental implant prosthetics.The follow-up time was 12 months, all patients achieved successful implantation and good osseointegration around the implant. The esthetic results were perfect .Among the 90 cases, 90.7%, 92.8% and 95.5% of the patients were satisfied with the final outcomes 3,6,12 months after prosthetics.Good clinical effectiveness and satisfaction on aesthetic effectiveness can be obtained with GBR technique applied in maxillary lateral incisor implant site. Appropriate use of GBR technique is the solution of bone defect of maxillary lateral incisor implant site.