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Improvement in thermal stability is especially important for the oxide/oxide composites, which are widely applied at high temperatures. Herein, the continuous alumina fiber reinforced alumina matrix (Al 2 O 3 /Al 2 O 3) composites were fabricated at 1200–1400 °C using Al 2 O 3 powders with a mean size of 0.6 μm. The Al 2 O 3 /Al 2 O 3 composite fabricated at 1300 °C achieved a high flexural strength of 392.9 ± 20.1 MPa and a high interlaminar shear strength of 20.6 ± 1.0 MPa. After exposure at 1000 °C for 100 h and 1400 °C for 10 min, the 1300 °C fabricated Al 2 O 3 /Al 2 O 3 composite showed no significant reduction in mechanical properties. A slight decrease in mechanical properties was observed after aging at 1200 °C for 100 h. The high strength retention after the heat treatment benefited from the coarse Al 2 O 3 powders, which could not be easily sintered at high temperatures. This work can expand the selection of the Al 2 O 3 /Al 2 O 3 composites for potential applications at service temperatures as high as 1400 °C for a short term. [ABSTRACT FROM AUTHOR]

In recent years, two-dimensional van der Waals (2D vdWs) heterostructures have attracted great research interest due to their great potential in fundamental physics research and spintronic devices (such as MTJs). Due to its excellent scalability, controllable magnetism and out-of-plane anisotropy, the compact nonvolatile memory controller (NV-MC) based on spintronics is expected to solve the memory bottle-neck problem. At present, a series of in-depth studies have been conducted on advanced 2D vdWs materials, such as MoS2, WSe2, and Fe3GeTe2 (FGT). The results show that the 2D vdWs materials have great TMR value and high SOT switching efficiency, both theoretically reported and experimentally verified. In the paper, a novel MTJ device based on the FGT/WTe2 heterostructure is proposed. In the absence of an external magnetic field, the magnetization direction of the MTJ free layer can still be reversed with certainty when the unipolar write current reaches about 5 mA. Moreover, the DMI effect generated between 2-D material/FM interfaces is also considered, which can promote the performance of SOT-MTJ without the external field. The reading reliability of SOT-MRAM is improved in comparison with the traditional CoFeB-based MTJ device. [ABSTRACT FROM AUTHOR]

Inevitable process variations (PVT) brought by both the magnetic tunneling junction (MTJ) and MOSFET based on the complementary metal-oxide semiconductor (CMOS) technology become a major obstacle for the mass production of spin transfer torque magnetic random access memory (STT-MRAM). The detriment of the process variations leads to a serious degradation in the fundamental yield with the shrinkage of the technology nodes. However, the conventional data-cell-variation-tolerant (DCVT) sense scheme cannot get the target read yield due to the limited sense margin (SM). To resolve this problem, a DCVT triple sampling non-destructive self-reference sensing scheme (TSNS) is proposed in the paper, which doubles the SM, with lower power consumption and better SM compared with the conventional DCVT sense scheme. Monte Carlo simulation with industry-compatible 65-nm model parameters results show that the proposed sensing scheme shows over 2.5 times higher SM and less power consumption compared to the previous self-reference circuit. The proposed sensing scheme can get the target read yield with lower power consumption. [ABSTRACT FROM AUTHOR]

With the development of electronic technology, semiconductor memory is gradually shifting toward smaller area with less power consumption. SOT-MRAM is one of the competitive substitutes for DRAM and SRAM due to its superior endurance and switching speed. In contrast to STT-MRAM, the separation of read and write routes allows SOT-MRAM to have a lower error rate and higher lifetime, but this comes at the expense of the memory density. In recent years, vertical integrated circuits have relied on TSV to complete 3D stacking to ease the pressure of Moore's Law on scaling circuits. SOT-MRAM can take advantage of 3D stacking to reduce power and latency. More importantly, the density of SOT-MRAM can be improved at the same time. In the paper, simulation is conducted based on DESTINY, with the TSV model supplemented to NVSIM to evaluate the performance of MRAM 3D structures. The 3D SOT-MRAM structure in DESTINY can be implemented with a bus layer and interconnect structure between layers, which greatly reduces the expense of area. However, the 3D structure requires a more complex interconnect structure to truly meet the requirements of high density. For this reason, 3D model of unit interconnection using TSV is presented in the paper. Memory has several components, of which the memory array is the one with the largest area share. This paper explores the spatial structure of the array and proposes a new model which allows more complex interconnect structures to be accomplished on the same area. [ABSTRACT FROM AUTHOR]

With the rapid development of portable computing devices and users' demand for high-quality graphics rendering, embedded Graphics Processing Units (GPU) systems for graphics processing are increasingly turning into a key component of computer architecture to enhance computability. The cache system based on traditional static random access memory (SRAM) plays a crucial role in GPUs. But high leakage, low lifetime and poor integration problems deeply plague the science and engineering field. In the paper, a novel magnetic random access memory (MRAM) based cache architecture of GPU systems is proposed for highly efficient graphics processing and computing accelerating, with the merits of high speed, long endurance, strong interference resistance, and ultra-low power consumption. Spin transfer torque-MRAM and spin orbit torque-MRAM are utilized in off-chip and on-chip caches, respectively. A controller design scheme with prefetching modules and optimized cache coherency protocols are adopted. After testing and evaluating with multiple loads, neural network models and datasets, the simulation results show that the proposed system can achieve up to 28%, 56%, and 66.45% optimizations mostly in terms of speed, energy and leakage power, respectively. [ABSTRACT FROM AUTHOR]

With the development of Artificial Intelligence (AI) in recent years, the fields of computer, biology, medicine, and aerospace have demanded higher requirements for the processing and storage of information. In this paper, a novel Magnetic Tunnel Junction (MTJ) based Spin-Orbital Torque Magnetic Random Access Memory (SOT-MRAM) composed of Fe3GeTe2 (FGT) is employed as a storage medium in the computer architecture. On the basis of the analysis of the fundamentals, model configuration, characteristics and performance advantages of the FGT based SOT device, a hybrid storage (L1, L2, Last Level Cache) is constructed, with FGT-SOT-MRAM, conventional SOT-MRAM and STT-MRAM replacing the original static random access memory (SRAM) in the novel triple-level CPU cache architecture. This can override the increasing leakage problem of SRAM, while opening up the application of two-dimensional van der Waals ferromagnets in computer systems at the L1 cache level. Meanwhile, an innovative cache optimization scheme is put forward for magnetic memory to better match the performance of FGT-SOT-MRAM to CPU. The simulation results demonstrate that the FGT-based MRAM can achieve up to 38.03% IPC optimization and 53.41% power optimization in the CPU cache system in contrast to the conventional ones. [ABSTRACT FROM AUTHOR]

In this paper, the magnetic immunity model of STT-MRAM is established. The influence of the external magnetic field on the effective energy barrier of STT-MRAM is investigated, which is the crucial issue to influence the reliability of STT-MRAM cells in the standby, active read and active write modes. The influence factors on the magnetic immunity of STT-MRAM array are also discussed in the paper, such as the electrode, package material, insert layer and array spacing, etc. Moreover, the magnetic shield models in the BGA and QFP packages are designed and analyzed for the enhancement of the magnetic immunity of STT-MRAM, whose shielding efficiency is up to 98.2%. [ABSTRACT FROM AUTHOR]

Electrically driven magnetization switch has attracted much attention in the new spintronic memory, especially for spin–orbit torque (SOT)-based magnetic random access memory (MRAM). However, the published models are facing limitations with the continuous shrinkage of the feature size down to nanoscale. Also, the thermal effect caused by switching operation is non-negligible. Therefore, an effective model is needed to represent the switching dynamic of the device concerning the influences of the nanoscale and the thermal effect. In the paper, a compact model of three-terminal SOT-driven switching is established. The influence of the voltage-controlled magnetic anisotropy (VCMA) and spin transfer torque (STT) effect induced by bias voltage on the field-free SOT-driven switching is considered by numerically solving the LLG equations. Furthermore, a 3D model of the SOT-MTJ device is established by finite element method to trace the thermoelectric behavior inside the device. The thermoelectric behavior is integrated into the compact model to show the influence of the temperature on the switching behavior, highlighting the importance of the thermal effect for the realistic modelling of SOT-driven switching. Finally, a novel voltage pulse scheme is proposed, which can effectively shorten the switching time and improve the reliability of the device. The established model could provide strategies and guidelines for next-generation memory design and application. [ABSTRACT FROM AUTHOR]

In the paper, novel multi-bit parallel pipeline circuit design of STT-MRAM is proposed to improve the read and write efficiency. The shift register is utilized to change the series data into the parallel ones. Combined with the corresponding sense amplifier (SA) circuit and the write drive circuit, 4-bit data can be read or written in parallel in single cycle. With the 32 Kbit data test, the efficiencies of the read and the write operations of the proposed pipeline circuit are increased by 72.3% and 74.4%, separately, with the comparison of the incumbent series operations. The proposed strategy has potential application in the embedded high speed STT-MRAM. [ABSTRACT FROM AUTHOR]

Spin-transfer-torque magnetic random access memory (STT-MRAM) based on magnetic tunnel junction (MTJ) device has attracted significant attention from academics and industries. Nevertheless, the thermal effect under bias operation affects the overall performance and stability of a device. To evaluate the thermal phenomenon in MTJ devices accurately, the non-equilibrium effect between the electron and the phonon near the electrode-barrier interface cannot be ignored. The existence of the interface leads to additional thermal resistance hindering the heat conduction of tunnel junction. Therefore, an effective equivalent model concerning the interface effect is necessary to represent the heat transportation of the device. In this article, a nanoscale thermal transport model of the MTJ device is proposed. The influence of the thermal conductivity of the nano-oxide layer on the temperature distribution is discussed. The interface energy balance transport model is used to clarify the non-equilibrium relationship between the phonon and the electron at the CoFeB/MgO/CoFeB interfaces. A parameterization study is conducted to illustrate the temperature distribution in the nanoscale thermal transport model. Furthermore, the phonon-electron coupling distance ($\delta$) based on the thermal conductivity of the phonon ($\kappa _{p}$) and the electron ($\kappa _{e}$) of the device is implemented to construct the effective equivalent model using finite element modeling (FEM), which could realistically reflect the thermal transport under working conditions. The established equivalent model has a guiding role in exploring the thermal transportation in the nanoscale MTJ device. [ABSTRACT FROM AUTHOR]

Current-induced domain wall motion (CIDWM) shows promising prospects with low power, high density, high speed, and so on. Recent studies have demonstrated that magnetic tunnel junction (MTJ) based on CIDWM has great potential in mimicking a non-volatile artificial neuron and synapse. By combining the effect of the interfacial Dzyaloshinskii–Moriya interaction (DMI) to stabilize the Néel-type domain wall (DW) and the high-speed low-power advantages of spin orbit torque (SOT), the novel MTJ device is experimentally demonstrated with low threshold current and high propagation speed, which shows potential applications in the field of the artificial neuron and synapse. In this article, a compact model for CIDWM-MTJ based on SOT and DMI is presented. The model integrates the SOT mechanism for magnetization reversal and DW nucleation, CIDWM behaviors, and tunnel resistance theory of MTJ nanopillar. The micromagnetic simulation and the temporal evolution of the DW position are implemented by solving the Landau–Lifshitz–Gilbert (LLG) equation and the 1-D model. Based on the developed model, a hybrid CIDWM-MTJ/CMOS circuit is simulated for verification. The presented model combines the CIDWM dynamics and the MTJ magnetic dynamics, showing potential application for the simulation of all-spin artificial neural network (ANN). [ABSTRACT FROM AUTHOR]

A fast writing strategy of spin transfer torque (STT) magnetic random access memory (STT-MRAM) combined with pipeline architecture and early write termination (EWT) technology is proposed in this article. Both the writing speed and the writing power consumption of STT-MRAM are optimized. First, based on the proposed pipeline structure, the writing operation can be conducted within a single clock cycle, much decreasing the writing time. Second, the EWT technology is adopted in the writing operation. In the traditional operation of STT-MRAM, the same data are repeatedly written to the memory cell, which wastes the writing power consumption and the writing operation time. In this article, combined with the EWT technology and the pipeline architecture, the unnecessary writing power is reduced by 92.8%, while the necessary writing power is increased by 19.8%. Taking 32 kb data for the writing operation, the operation speed of the new writing strategy is increased by 67.4% compared with the incumbent writing technology. The proposed strategy has potential application in the embedded STT-MRAM acting as cache memory in the computer system. [ABSTRACT FROM AUTHOR]

A novel CMOS hexaferrite circulator with a Y-junction structure is designed and fabricated, which is compatible with standard CMOS technology. The spin-coating approach is adopted during the fabrication, in which the photoresist is mixed with nano-hexaferrite powder for preparation of a magnetic thin film in the device. Compared with the traditional circulator with an external permanent magnet for operation, the novel circulator can utilize the spin-coating magnetic film and is compatible with CMOS technology. The remanent magnetization of the adopted hexaferrite thin film can provide the required magnetic field for reciprocity properties. The optimization of impedance matching and the improvements in the related parameters are demonstrated on the novel CMOS circulator. The CMOS circulator exhibits the merits of small volume and easy integration while keeping its promising non-reciprocity properties. The fabrication is conducted based on the standard 180-nm CMOS technology. S-parameter measurements on the circulator show that the device has an isolation of 20 dB over 520 MHz bandwidth at 26.2 GHz. The minimum insertion loss is 1.81 dB. The novel CMOS-compatible circulator has potential application in 5G wireless communication systems. [ABSTRACT FROM AUTHOR]

A predictive algorithm for accurately determining the crosstalk peaks caused by SiC MOSFETs is proposed in this article, which is very important to better design the drive and protect circuits of SiC MOSFETs. Compared to the conventional algorithm of crosstalk peaks, the nonlinearity of gate-drain capacitance (Cgd) is first considered in the proposed algorithm. In detail, the differential expression of the crosstalk peaks is deduced, in which, the main factors affecting crosstalk peaks are all included. Following, the execution flow of the predictive algorithm is provided according to the differential expression. To verify the accuracy of the proposed algorithm with considering the nonlinearity of Cgd, the simulation and experiment platforms are established and verified by using Kelvin packaged SiC MOSFET IMZ120R045M1 (1200 V/52 A). The calculation results of the proposed algorithm are compared with the conventional algorithm without considering the nonlinearity of Cgd under different working conditions of SiC MOSFET. Finally, the calculation results, the simulation, and experiment results show that the proposed algorithm is effective and has better accuracy. Therefore, the predictive algorithm proposed in this article provides a theoretical reference to better design the drive and protect circuits of SiC MOSFETs. [ABSTRACT FROM AUTHOR]

The emergence and growing maturity of spintronics present new ideas and methods for low-power integrated circuit design. Spin-transfer torque magnetic tunnel junction (STT-MTJ) device is one of the spintronic candidates for future promising non-volatile memory. In this paper, a compact model for the STT-MTJ device in nanoscale is presented. By analyzing the influence of the device scale on its properties, the scale effect of the MTJ device is included. The thermal stability factor is trimmed to reflect the error rate of the scale effect of the device. Based on the compact model, the simulation is conducted with different device sizes to present the influence of the scale effect on the device characteristics, including the resistance, the critical current, the switching time, the write error rate, and other characteristics. [ABSTRACT FROM AUTHOR]

Accurate segmentation of choroidal thickness (CT) and vasculature is important to better analyze and understand the choroid-related ocular diseases. In this paper, we proposed and implemented a novel and practical method based on the deep learning algorithms, residual U-Net, to segment and quantify the CT and vasculature automatically. With limited training data and validation data, the residual U-Net was capable of identifying the choroidal boundaries as precise as the manual segmentation compared with an experienced operator. Then, the trained deep learning algorithms was applied to 217 images and six choroidal relevant parameters were extracted, we found high intraclass correlation coefficients (ICC) of more than 0.964 between manual and automatic segmentation methods. The automatic method also achieved great reproducibility with ICC greater than 0.913, indicating good consistency of the automatic segmentation method. Our results suggested the deep learning algorithms can accurately and efficiently segment choroid boundaries, which will be helpful to quantify the CT and vasculature. [ABSTRACT FROM AUTHOR]

There is increasing evidence showing that the dynamic changes in the gut microbiota can alter brain physiology and behavior. Cognition was originally thought to be regulated only by the central nervous system. However, it is now becoming clear that many non-nervous system factors, including the gut-resident bacteria of the gastrointestinal tract, regulate and influence cognitive dysfunction as well as the process of neurodegeneration and cerebrovascular diseases. Extrinsic and intrinsic factors including dietary habits can regulate the composition of the microbiota. Microbes release metabolites and microbiota-derived molecules to further trigger host-derived cytokines and inflammation in the central nervous system, which contribute greatly to the pathogenesis of host brain disorders such as pain, depression, anxiety, autism, Alzheimer's diseases, Parkinson's disease, and stroke. Change of blood-brain barrier permeability, brain vascular physiology, and brain structure are among the most critical causes of the development of downstream neurological dysfunction. In this review, we will discuss the following parts: Overview of technical approaches used in gut microbiome studiesMicrobiota and immunityGut microbiota and metabolitesMicrobiota-induced blood-brain barrier dysfunctionNeuropsychiatric diseases ■ Stress and depression■ Pain and migraine■ Autism spectrum disordersNeurodegenerative diseases ■ Parkinson's disease■ Alzheimer's disease■ Amyotrophic lateral sclerosis■ Multiple sclerosisCerebrovascular disease ■ Atherosclerosis■ Stroke■ Arteriovenous malformationConclusions and perspectives. [ABSTRACT FROM AUTHOR]

Micro direct methanol fuel cells (μDMFCs) are a promising power source for microelectronic devices and systems. As the operating state and performance of a μDMFC is generally determined by both electrochemical polarization and methanol crossover, it is important to monitor the methanol concentration in μDMFCs. Here, we design and fabricate a microwave sensor and integrate it with a μDMFC for the online detection of methanol concentration in a nonintrusive way. The sensing area is set at the bottom of the anode chamber of a μDMFC which exhibits a maximum output power density of 28.8 mW cm−2 at 30 °C. With a square ring structure, the dual-mode microwave sensor shows a sensitivity of 9.5 MHz mol−1 L. Furthermore, the importance of methanol concentration monitoring is demonstrated in the long term. A relatively smooth methanol decline curve was obtained, which indicated a normal and stable operating status of the μDMFC. Derived from real-time recording data, fuel utilization was additionally calculated as 28.5%. [ABSTRACT FROM AUTHOR]

Abstract We have investigated two solid-state phase transformations-nitriding of the ternary alloy FeCuB ribbons and martensitic phase transformation in the FeCuBN ribbons using x-ray diffraction, Auger Electron spectroscopy, and scanning electron microscopy. We also studied the diffusion kinetics of nitrogen in FeCuB ribbons and found the activation energy of N to diffuse in the FeCuB matrix and the diffusion coefficient of N at different temperatures. We investigated the evolution of the microstructure during nitriding process and found a layered growth of iron nitride in the FeCuB matrix. Finally, the martensitic phase transformation of the FeCuBN ribbons was also optimized, and the optimizing parameters for the martensitic phase transformation of FeCuB ribbons were reported. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

A novel synthesis approach is developed to prepare nanocrystalline γ'-Fe4N in this paper. High energy cryomilling approach in liquid nitrogen is used to prepare the sample. A FexN amorphous state with a degree of metastable supersaturation of N into Fe is obtained. The crystalline size after higher energy cryomilling approach is characterized to be 40 ∼ 80 nm. A post-annealing among 200 ∼ 300 °C for 10 minutes results in phase transformation from α-iron into γ'-Fe4N. Its magnetic properties and structures are characterized, showing good soft magnetic material with ultralow coercivity (0.7 Oe). It shows high electrical resistivity (375 μΩ·m) at room temperature. The feasibility of the ball milling synthesis approach in liquid nitrogen is verified, suggesting a novel approach for the soft magnetic material preparation. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs) have attracted wide attention because of their unique structure and properties. However, the prepared CNTs often present agglomeration state, which destroys the excellent properties of single carbon nanotubes and seriously affects the application of carbon nanotubes. How to effectively disperse carbon nanotubes has become an urgent problem to be solved. There are many factors affecting the dispersion of carbon nanotubes. In this paper, the effects of three aspects of surfactant, ultrasonic oscillation and centrifugation on the dispersion of carbon nanotubes and fiscal policies for the development of nano high-tech industry are mainly studied. [ABSTRACT FROM AUTHOR]

To evaluate the relationship between exposure to air pollutants and respiratory emergency room visits, a generalized additive model (GAM) was used to analyze the exposure-effect relationship between air pollutants and respiratory emergency room visits. The results showed that NO, SO, and PM have positive relationships with respiratory disease. Concentration increases of 10 μg/m in NO, SO, and PM corresponded to 3.90% (95%CI 3.56-4.25), 0.81% (95%CI −0.09-1.72), and 0.64% (95%CI 0.55-0.74) increases in respiratory emergency room visits. In addition, there is a strong synergic effect of PM and NO on respiratory diseases. The threshold values of the national standard grade II limits used in Beijing should be adjusted. An appropriate standard could effectively promote a significant decline in respiratory room visits and would eventually be beneficial to air quality management in residential areas. [ABSTRACT FROM AUTHOR]

With the rapid growth of big data information and the continuous iteration progress of CPU architecture, the implementation of a new memory-based cache architecture is urgent and challenging. In the paper, a CPU cache architecture system based on MRAM is built. Firstly, the performance of SRAM, STT-MRAM and SOT-MRAM as caches from 8 kb to 32 Mb is evaluated. Secondly, by summarizing the performance of SRAM and MRAM in different cache levels, a new quad-core CPU cache architecture design scheme with SOT-MRAM as the first level of cache and STT-MRAM as the second level of cache is determined. Thirdly, the built cache system is simulated. A non-inclusive strategy is proposed to replace the inclusive strategy in order to solve the problem of high dynamic energy of STT-MRAM at the second level. The idea of having a quad-core CPU dynamically share the second-level cache is proposed in the paper. Finally, the caching system in the paper is compared with the other previous works, showing up to 60.78% energy consumption advantage and 33.22% leakage power advantage. The proposed MRAM-based CPU cache system and the corresponding cache strategy have potential application with the benefits of low power and less area. [ABSTRACT FROM AUTHOR]

Abstract: The rhenium (I) complex [Re(CH3CN)3Br2(NO)] catalyzes the homogeneous hydrosilylation of a variety of substituted acrylonitriles, which were converted into the corresponding silyl-substituted alkanes with high regioselectivity of up to 94%. The products were analyzed by 1H NMR and GC–MS. A rhenium specific mechanism is proposed for the hydrosilylation of olefins. [Copyright &y& Elsevier]

A magnetic tunnel junction-based register with separate read and write paths is proposed in this paper. Analysis of the operation of the circuit is performed, and methods for determining the key parameters of the device are presented. The simulation of the circuit is performed in Verilog-A, and the simulation results demonstrate the operational characteristics of the circuit. This new spin-based flip flop offers a 23% reduction in the number of devices and a 23.6% reduction in its dissipated power when compared with a pure CMOS implementation with the added benefit of nonvolatility. A 4-b shifter based on the proposed spin register is presented, too. [ABSTRACT FROM PUBLISHER]

As a new clean renewable energy, Perovskite solar cells (PSC) has become a research hotspot. The multi-step diffusion method can effectively control the composition and proportion of the precursor liquid, regulate the crystallization process and the final morphology of the perovskite film, thereby obtaining a smooth and dense high-quality perovskite film; The introduction of micro-Mg element makes the Fermi energy level of TiO 2 electron transport layer move up, enhances conductivity, and reduces surface defect states. Correspondingly, after Mg doping, the series resistance of planar perovskite battery decreases, the electron transmission speed becomes faster, and the charge collection efficiency is improved under high bias voltage; In the process of deposition of perovskite film by one-step inverse solvent method, polystyrene (PS) is introduced to cover the surface of polycrystalline perovskite film and fill the grain boundary to form a protective layer covering single grain. On the one hand, PS coating can effectively inhibit the volatilization and phase separation of organic components in perovskite films at high temperature, and maintain the stability of film components and phase, on the other hand, PS coating can effectively prevent the corrosion of perovskite film by water, and improve the moisture stability and self-repair ability of the film. In addition, since the self-adhesive porous carbon has good flexibility, compressibility, and adhesion to the electrode, it can be applied to perovskite solar cells. After the pressure is transferred, the carbon counter electrode can form an excellent interface contact with the hole transport layer, which promote the interface charge extraction and solve the interface contact problem existing in carbon-based perovskite batteries for a long time. The purpose of the paper is to provide the basis for exploring the technology of PSCs preparation on a large scale. [ABSTRACT FROM AUTHOR]

The current economic growth model has changed from efficiency development to innovation development. Ecological environment and other problems are still very prominent, the industry is lack of close integration, universities and scientific research institutions lack a sound science and technology service system. The purpose of this study is to explore the functions of eco-innovation ecosystem based on smart city blockchain, put forward relevant policy recommendations, and provide theoretical and practical guidance for the development of an innovation ecosystem. Through the methods of network survey, macro cluster analysis and typical case analysis, present study analyzes the development of derivative products and the research status of an innovation ecosystem. Blockchain can be regarded as a trusted distributed database. Four core mechanisms, namely P2P network communication mechanism, blockchain account book storage mechanism, password mechanism and consensus mechanismare used to ensure the distributed, tamper-proof and non-repudiation characteristics of the system, which makes the blockchain system "honest" and "transparent". It has the characteristics of a wide range, cross-subject, high efficiency and low cost in application. Taking the city as an example, this paper investigates the development of the green building industry and the relationship between the innovation ecosystem. The results showed that the α coefficient reliability index of all variables was above 0.8 in terms of ecological reliability and validity, which proved that all the scales in this study had good reliability, KM0 values were more than 0.7, and the degree of freedom was high, and all the scales had high convergence validity. Among the research objects associated with the ecosystem, "technological innovation" accounts for the largest proportion of 28% in the region, and the lowest proportion is 5% of high-tech enterprises. [ABSTRACT FROM AUTHOR]

Adapting to climate change is critical to building sustainable and resilient agricultural systems. Understanding farmers' perceptions of climate change has become the key to the effective implementation of climate change adaptation policies. This research draws multidisciplinary attention to how farmers participate in decision-making on adaptation behaviors and provides useful insights for realizing synergies between environmental change and agricultural production. In this work, we conducted a meta-analysis of 63 quantitative studies on Chinese farmers' adaptation to climate change to assess the relationship between motivational factors and adaptation behavior. Our analysis highlights that farmers' perceptions of precipitation changes are often inaccurate; however, other psychological factors, such as perception, experience, and risk attitude, significantly positively impact their adaptation behavior. In addition, different climate regions are the main source of high heterogeneity in inter-study comparisons of climate change perception, and the effect of climate regions may therefore constitute a moderating factor that weakens the positive relationship between climate change perception and adaptive behavior. Furthermore, this study highlights the need to intervene at the household level to enhance farmers' adaptability to climate change, which includes providing support through income diversification, early warning information services, training, assistance, credit, subsidies, and other resources. In the future, research on how perception, experience, and risk interact to affect adaptive behavior should be strengthened. • Provides a quantitative summary of the literature on smallholders' climate change adaptation behavior. • Farmers' perceptions of precipitation changes were often inaccurate. • Paying attention to farmers' psychological characteristics is important to explain climate change adaptation behavior. • Both informal and formal institutional interventions can exert positive effects on smallholder adaptation to climate change. [ABSTRACT FROM AUTHOR]

Fine particulate matter (PM 2.5) exposure is associated with stroke incidence and mortality. However, the global distribution and trends of stroke burden and mortality attributable to PM 2.5 are rarely studied. We estimated the spatial patterns and temporal trends of PM 2.5 -attributable stroke burden in 195 countries and territories from 1990 to 2017. Detailed data on stroke burden attributable to PM 2.5 were extracted from the Global Burden of Disease Study (GBD) 2017. The numbers and age-standardized rates of stroke disability-adjusted life years (DALYs) and mortality (ASDR and ASMR) were estimated by age, sex, subtype, region, and country. Temporal trends in ASDR and ASMR were analyzed using estimated annual percentage change (EAPC). Globally, in 2017, 10.5 million DALYs and 0.4 million deaths related to stroke were attributable to PM 2.5. The corresponding ASDR and ASMR increased with age, were highest in males and for intracerebral hemorrhage, and varied greatly across countries, with the largest burden in high-middle sociodemographic index (SDI) regions and East Asia. The global ASDR and ASMR decreased by 7.2% and 12.2% from 1990 to 2017, with EAPCs of −0.42 (95% confidence interval [CI]: -0.55, −0.28) and −0.57 (95% CI: -0.72, −0.42), respectively. Age-specific stroke burden rates declined significantly, except in the middle-aged population. The decrease was more pronounced in women and for subarachnoid hemorrhage, while proportions of ischemic stroke burden increased globally and in all SDI regions. Most geographic regions achieved significant declines in ASDR and ASMR since 1990; however, Asia and approximately 30% of countries and territories, especially in low-income countries, showed undesirable increasing trends. The patterns and trends were heterogeneous across countries. Strengthened and tailored approaches for stroke prevention and air pollution management are still needed to reduce the disease burden associated with PM 2.5 , particularly in males, middle-age populations, and low-income countries and for ischemic stroke. • Stroke burden attributable to PM 2.5 varied greatly across countries. • The age-standardized rate (ASR) of PM 2.5 -attributable stroke burden were decreased in most regions. • The reduction in the ASR was more pronounced in women and for subarachnoid hemorrhage. • Ischemic stroke burden attributable to PM 2.5 significantly increased since 1990. • Asia and about 30% of countries showed increased trends in ASR, especially in low-income countries. [ABSTRACT FROM AUTHOR]

Smoking is a well-defined modifiable risk factor for dementia. Understanding national temporal trends of dementia deaths due to smoking is critical for prioritizing action for the global prevention of dementia, as well as smoking prevention. We aimed to estimate the patterns and temporal trends of smoking-attributable dementia-related deaths for 195 countries from 1990 to 2017. Detailed data on dementia deaths attributable to smoking were obtained from the Global Burden of Disease Study 2017. The estimated annual percentage change (EAPC) was used to quantify the temporal trends in the age-standardized mortality rate (ASMR) of dementia attributable to smoking by age, sex, region, and country. In 2017, approximately 2.51 million deaths attributable to dementia occurred globally; among them, 317,747 dementia-related deaths were attributable to smoking. The corresponding ASMR decreased by 31.1% from 6.33 per 100,000 population in 1990 to 4.36 per 100,000 population in 2017, with an EAPC of −1.43 (95% CI -1.48, −1.37). The reduction in the ASMR in women (EAPC = −2.13; 95% CI -2.18, −2.08) was more pronounced than that in men (EAPC = −1.26; 95% CI -1.32, −1.20). Most geographic region have achieved significant declines in ASMRs since 1990; however, Central Asia and 24 countries and territories showed increased trends in ASMRs over the same period. Despite large reductions in the ASMRs of dementia attributable to smoking over the past three decades, the corresponding number of deaths has steadily increased due to population growth and aging. The ASMR trend patterns were heterogeneous across countries, and there were undesirable increases in the dementia ASMR in some countries. Strengthened efforts for tobacco prevention are still needed to reduce the disease burden due to smoking, particularly in countries where the dementia ASMR is increasing. • Trends of dementia deaths attributable to smoking for 195 countries were estimated. • Globally, the ASMR of dementia attributable to smoking were decreased. • The reduction in the ASMR in women was more pronounced than that in men. • Most geographic region have achieved significant declines in ASMRs since 1990. • Central Asia and 24 countries and territories showed increased trends in ASMRs. [ABSTRACT FROM AUTHOR]

Objectives An altered microbiota, which can be described quantitatively, has been identified as playing a pivotal role in host vascular physiology, and it may contribute to various diseases. The aim of this study was to better understand the role of the gut microbiota in vascular physiology in a subclinical elderly population, and to investigate how lifestyle affects the composition of host gut microbiota to further impact the pathogenesis of vascular diseases. Methods We performed a population-based faecal metagenomic study over 569 elderly asymptomatic subclinical individuals in rural China. An association network was built based on clinical measurements and detailed epidemiologic questionnaires, including blood chemistry, arterial stiffness, carotid ultrasonography, and metagenomic datasets. Results By analyzing the breadth, depth and impact of each node of the association network, we found carotid arterial atherosclerosis indices, including intima-media thickness (IMT), were essential in the network, and were significantly associated with living habits, socio-economic status, and diet. Using mediation analysis, we found that higher frequency of eating fresh fruits and vegetables, and more exercise significantly reduced carotid atherosclerosis in terms of IMT, peak systolic velocity and end-diastolic velocity values through the mediation of Alistepes , Oligella and Prevotella. Gut microbes explained 16.5% of the mediation effect of lifestyle on the pathogenesis of carotid atherosclerosis. After adjustment, Faecalicatena [odds ratio (OR) = 0.12 ∼0.65] was shown to be protective against the formation of carotid atherosclerosis, independently, while Libanicoccus (OR = 1.46 ∼4.20) was associated with increased carotid arterial IMT. KEGG/KO Kyoto Encyclopedia of Genes and Genomes/ KEGG Orthology (KEGG/KO) analyses revealed a loss of anti-inflammation function in IMT subjects. Conclusion Our study revealed a Chinese population–wide phenotype–metagenomic association network and a mediation effect of gut microbiota on carotid artery atherosclerosis, hinting at potential therapeutic and preventive uses for microbiota in vascular diseases. [ABSTRACT FROM AUTHOR]

This mediation analysis aimed to investigate the associations among areal bone mineral density, mobility-related brain atrophy, and specific gait patterns. A total of 595 participants from the Taizhou Imaging Study, who underwent both gait and bone mineral density measurements, were included in this cross-sectional analysis. We used a wearable gait tracking device to collect quantitative gait parameters and then summarized them into independent gait domains with factor analysis. Bone mineral density was measured in the lumbar spine, femoral neck, and total hip using dual-energy X-ray absorptiometry. Magnetic resonance images were obtained on a 3.0-Tesla scanner, and the volumes of brain regions related to mobility were computed using FreeSurfer. Lower bone mineral density was found to be associated with higher gait variability, especially at the site of the lumbar spine (β = 0.174, FDR = 0.001). Besides, higher gait variability was correlated with mobility-related brain atrophy, like the primary motor cortex (β = 0.147, FDR = 0.006), sensorimotor cortex (β = 0.153, FDR = 0.006), and entorhinal cortex (β = 0.106, FDR = 0.043). Bidirectional mediation analysis revealed that regional brain atrophy contributed to higher gait variability through the low lumbar spine bone mineral density (for the primary motor cortex, P = 0.018; for the sensorimotor cortex, P = 0.010) and the low lumbar spine bone mineral density contributed to higher gait variability through the primary motor and sensorimotor cortices (P = 0.026 and 0.010, respectively). [ABSTRACT FROM AUTHOR]

A three-dimensional (3D) printable chipless radio frequency identification (RFID) tag, with high density and sensitivity, is proposed and fulfilled on insulator substrates. By printing a rectangular slot ring and designing specific geometry on the substrate, the printed structure shows high sensitivity in a resonant manner, with the benefits of high density and low cost. Considering the multiple rectangular rings with different sizes in a concentric distribution, a bit coding sequence can be observed in frequency spectra because of the corresponding different resonant frequencies aroused by the printed slots. In this way, the 3D printable chipless RFID tag can be fulfilled by adopting the structure of the rectangular slot ring on the insulated substrates. The main characteristics of the designed rectangular slot rings are verified on both flexible and solid substrates. A 12-bit chipless tag based on the slot ring structures is designed and implemented. The simulation and experiment results show good agreement on its characteristics. The frequency response reveals the fact that the 2th, 3th and 4th harmonic do not exist, which is a unique merit for improving the encoding capacity and the sensitivity of the corresponding reader. The electric field direction of the electromagnetic wave of the reader excitation tag is demonstrated to be wide, up to 90° on the tag horizontal plane, 30° on the vertical direction. [ABSTRACT FROM AUTHOR]

Background: Predictions of primary liver cancer (PLC) incidence rates and case numbers are critical to understand and plan for PLC disease burden.Methods: Data on PLC incidence rates and case numbers from 1990 to 2017 were retrieved from the Global Burden of Disease database. The estimated average percentage change (EAPC) was calculated to quantify the trends of PLC age-standardized incidence rates (ASRs). Bayesian age-period-cohort models were constructed to project PLC incidence rates and case numbers through 2030.Results: Globally, the PLC case number doubled from 472 300 in 1990 to 953 100 in 2017. The case number will further increase to 1 571 200 in 2030, and the ASR will increase from 11.80 per 100 000 in 2018 to 14.08 per 100 000 in 2030. The most pronounced increases are observed in people afflicted by non-alcoholic steatohepatitis (NASH) and in older people. The trends of PLC incidence rates between 1990 and 2030 are heterogeneous among countries and can be summarized as five scenarios: (i) 46 countries that have and will continue to experience a persistent increase (e.g. Australia); (ii) 21 countries that experienced an initial decrease (or remained stable) but are predicted to increase (e.g. China); (iii) 7 countries that experienced an initial increase but are predicted to remain stable (e.g. USA); (iv) 29 countries that experienced an initial increase but are predicted to decrease (e.g. Egypt); and (v) 82 countries that have and will continue to experience a persistent decrease (e.g. Japan).Conclusion: PLC incidence rates and case numbers are anticipated to increase at the global level through 2030. The increases in people afflicted by NASH and among older people suggest a dearth of attention for these populations in current prevention strategies and highlight their priority in future schedules for global control of PLC. [ABSTRACT FROM AUTHOR]

Background Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 infection, has been spreading globally. We aimed to develop a clinical model to predict the outcome of patients with severe COVID-19 infection early. Methods Demographic, clinical and first laboratory findings after admission of 183 patients with severe COVID-19 infection (115 survivors and 68 non-survivors from the Sino-French New City Branch of Tongji Hospital, Wuhan) were used to develop the predictive models. Machine learning approaches were used to select the features and predict the patients' outcomes. The area under the receiver operating characteristic curve (AUROC) was applied to compare the models' performance. A total of 64 with severe COVID-19 infection from the Optical Valley Branch of Tongji Hospital, Wuhan, were used to externally validate the final predictive model. Results The baseline characteristics and laboratory tests were significantly different between the survivors and non-survivors. Four variables (age, high-sensitivity C-reactive protein level, lymphocyte count and d-dimer level) were selected by all five models. Given the similar performance among the models, the logistic regression model was selected as the final predictive model because of its simplicity and interpretability. The AUROCs of the external validation sets were 0.881. The sensitivity and specificity were 0.839 and 0.794 for the validation set, when using a probability of death of 50% as the cutoff. Risk score based on the selected variables can be used to assess the mortality risk. The predictive model is available at [ https://phenomics.fudan.edu.cn/risk%5fscores/]. Conclusions Age, high-sensitivity C-reactive protein level, lymphocyte count and d-dimer level of COVID-19 patients at admission are informative for the patients' outcomes. [ABSTRACT FROM AUTHOR]

Spin transfer magnetoresistive random access memory (STT-MRAM) shows potential applications with the properties of non-volatility, low power consumption and high write/read speed. With the maturity of the STT-MRAM process, it has gradually entered the mass production stage. Reliability will be an important factor limiting the development of this device. Error correction technology is highly required to be developed on this specific memory circuit. In this paper, a combination of low density parity check (LDPC) is used on STT-MRAM, in which the encoding constructs a no 4-girth check matrix. In its fulfillment, the decoded method combines soft decision and hard decision. The simulation results demonstrate that the LDPC shows promising application scenario for STT-MRAM error correction, especially for large-capacity storage arrays. [ABSTRACT FROM AUTHOR]

Background: Liver cancer is a commonly diagnosed malignancy in China. The etiologies of liver cancer are widely known, although studies on temporal trends in liver cancer caused by specific etiologies are rare. Methods: Data on the incidence and mortality of liver cancer were retrieved from the Global Burden of Diseases Study 2017. The estimated annual percentage change (EAPC) was used to quantify temporal trends in the age‐standardized incidence rate (ASIR) and the age‐standardized mortality rate (ASMR) of liver cancer from 1990 to 2017. Results: Nationwide, the number of incident cases of liver cancer increased from 258 000 in 1990 to 515 900 in 2017. The ASIR decreased from 27.16 per 100 000 to 26.04 per 100 000 during this period, with an EAPC of −0.64 (95% confidence interval [CI] −0.84, −0.44). The number of deaths increased from 245 300 in 1990 to 418 200 in 2017, and the ASMR decreased from 26.72 to 21.30 (EAPC = −1.16, 95% CI −1.35, −0.97). The most pronounced decreases in the ASIR and ASMR were observed in liver cancer due to hepatitis B and in people aged 15‐49 years. Conclusions: Since the extensive efforts for prevention of hepatitis B virus infection, the incidence of liver cancer due to hepatitis B has significantly decreased. However, liver cancer due to hepatitis C, NASH, and other causes remains a major public health concern. Additional preventive strategies tailored to liver cancer are needed to further reduce its disease burden in China. [ABSTRACT FROM AUTHOR]

Background: Studies have examined the effect of weight change on osteoporosis, but the results were controversial. Among them, few had looked at weight change over the life span. This study aimed to fill this gap and investigate the association between lifetime body mass index (BMI) trajectories and bone loss. Methods: In this cross-sectional study, participants at age 50 and above were selected from the National Health and Nutrition Examination Survey (NHANES) 2005–2018. Dual-energy X-ray Absorptiometry was used to measure the bone mineral density at the femoral neck and lumbar spine. Standard BMI criteria were used, with < 25 kg/m2 for normal, 25–29.9 kg/m2 for overweight, and ≥ 30 kg/m2 for obesity. The latent class trajectory model (LCTM) was used to identify BMI trajectories. Multinomial logistic regression models were fitted to evaluate the association between different BMI trajectories and osteoporosis or osteopenia. Results: For the 9,706 eligible participants, we identified four BMI trajectories, including stable (n = 7,681, 70.14%), slight increase (n = 1253, 12.91%), increase to decrease (n = 195, 2.01%), and rapid increase (n = 577, 5.94%). Compared with individuals in the stable trajectory, individuals in the rapid increase trajectory had higher odds of osteoporosis (OR = 2.25, 95% CI 1.19–4.23) and osteopenia (OR = 1.49, 95% CI 1.02–2.17). This association was only found in the lumbar spine (OR = 2.11, 95% CI 1.06–4.2) but not in the femoral neck. In early-stage (age 25–10 years ago) weight change, staying an obesity and stable weight seemed to have protective effects on osteoporosis (OR = 0.26, 95% CI 0.08–0.77) and osteopenia (OR = 0.46, 95% CI 0.25–0.84). Meanwhile, keeping an early-stage stable and overweight was related to lower odds of osteopenia (OR = 0.53, 95% CI 0.34–0.83). No statistically significant association between recent (10 years ago to baseline) weight change and osteoporosis was found. Conclusions: Rapid and excess weight gain during adulthood is associated with a higher risk of osteoporosis. But this association varies by skeletal sites. Maintaining stable overweight and obesity at an early stage may have potentially beneficial effects on bone health. [ABSTRACT FROM AUTHOR]

Integrated circuits operated in the near-threshold region exhibit specific merit with high energy efficiency. A near-threshold model is highly required for the circuit design. In this paper, a near-threshold drain current model is proposed based on the surface inversion layer charge model for analyzing digital circuits. The short-channel effect in deep submicrometer is also included in the model. Moreover, the delay and energy parts based on the near-threshold drain current model are derived and integrated in the model. Two process design kits (PDKs) are used for parameter extraction to demonstrate the feasibility of the proposed model. The results show that the proposed model can be used for the near-threshold circuit calculation, with the benefit of high accuracy. [ABSTRACT FROM AUTHOR]

Background: Defects in DNA damage repair (DDR) pathways lead to genomic instability and oncogenesis. DDR deficiency is prevalent in esophageal squamous cell carcinoma (ESCC), but the effects of DDR alterations on mutational processes and tumor immune microenvironment in ECSS remain unclear. Methods: Whole‐exome and transcriptome sequencing data of 45 ESCC samples from Taizhou, China, were used to identify genomic variations, gene expression modulation in DDR pathways, and the abundance of tumor‐infiltrating immune cells. Ninety‐six ESCC cases from The Cancer Genome Atlas (TCGA) project were used for validation. Results: A total of 57.8% (26/45) of the cases in the Taizhou data and 70.8% (68/96) of the cases in the TCGA data carried at least one functional impact DDR mutation. Mutations in the DDR pathways were associated with a high tumor mutation burden. Several DDR deficiency‐related mutational signatures were discovered and were associated with immune cell infiltration, including T cells, monocytes, dendritic cells, and mast cells. The expression levels of two DDR genes, HFM1 and NEIL1, were downregulated in ESCC tumor tissues and had an independent effect on the infiltration of mast cells. In the Taizhou data, increased expression of HFM1 was associated with a poor prognosis, and the increased expression of NEIL1 was associated with a good outcome, but no reproducible correlation was observed in the TCGA data. Conclusion: This research demonstrated that DDR alterations could impact mutational processes and immune cell infiltration in ESCC. The suppression of HFM1 and NEIL1 could play a crucial role in ESCC progression and may also serve as prognostic markers. [ABSTRACT FROM AUTHOR]

A broadband circularly polarized (CP) printed monopole antenna which fed by coplanar waveguide (CPW) is proposed in the paper. The structure of the novel antenna includes a quarter circular disc radiating monopole, a coupled circular patch, and a bent L-shaped microstrip stub line. The L-shaped microstrip stub line is used to widen the impedance bandwidth and generate a horizontal component of the electromagnetic wave. The adoption of the asymmetric ground coplanar waveguide structure with the single-feed technology and the coupled circular patch, simultaneously achieve wide impedance bandwidth and wide axial ratio (AR) bandwidth. The structure parameters and the surface current of the designed antenna are analysed. The simulation and the measurement are conducted, showing good characterizations of the designed antenna. The 10-dB impedance bandwidth is 7.57 GHz, the fractional bandwidth from 6.05 to 13.62 GHz is 76.9%, the 3-dB axial ratio bandwidth is 3.01 GHz, and the fractional bandwidth from 6.05 to 9.06 GHz is 39.8%. The antenna can generate right/left hand circularly polarized waves in the direction of ± z axis. The designed antenna has wide applications in the fields of Internet of Things (IoT), broadband dual-CP communication systems and polarization diversity systems, wireless personal area network and other advanced communication systems. [ABSTRACT FROM AUTHOR]

A dual-mode control scheme is proposed in this letter to control a boost power factor correction (PFC) converter. The scheme combines both continuous and critical conduction modes and has the merits of simple control, high efficiency in a light-load condition, and being fit for personal computer (PC) power applications. The dual mode control circuit can be easily implemented into IC. The operating principles and control scheme are analyzed and discussed in detail. A 300 W boost power PFC prototype is implemented to verify the feasibility of the proposed scheme. The results prove to be satisfactory. [ABSTRACT FROM AUTHOR]

A micromachined thermopile infrared sensor is designed and optimized with high detective sensitivity in the article. A matched chopper operational amplifier with good linearity is implemented for signal processing. Optimizations of the sensor’s structure are proposed by the adjustment of the length of the thermocouple pairs and the filling of the back-etched cavity based on the adopted thermocouple materials. A passivation layer is implemented to minimize the flicker noise of the sensor. Based on the requirement of the optimized thermopile sensor system, both the flicker noise and the low-frequency noise of the system are suppressed for achieving high sensitivity. The chopper operational amplifier circuit with a single-ended closed-loop diagram is specifically designed for signal amplification and noise suppression. The fabricated device shows improved characterizations, with the responsivity of 182.72 V/W, detectivity of $2.47\times 10^{{8}}$ cmHz1/2/W, time constant of 10 ms, and total resistance of 270 $\text{k}\Omega $. The sensitivity of the designed system, including the sensor and the amplifier, is about 15 mV/°C, when the gain is 40 dB and the sensor-target distance is 3 cm. The system shows wide applications in the fields of noncontact temperature measurement and other special applications. [ABSTRACT FROM AUTHOR]

Spin-Torque-Transfer Magnetic Tunnel Junction (STT-MTJ) device shows wide applications in many important scenarios, including magnetic random access memory (MRAM), logic design, and high-frequency application. Its characterizations at the high frequency are studied intensively recently. In this article, the high-frequency properties of the STT-MTJ device are investigated thoroughly, including a de-embedding approach followed by an extraction procedure for removing the influences from the environment and the package. The de-embedding approach is performed on the STT-MTJ device operated at a high frequency, which can be used to calibrate its electrical characteristics by eliminating the environmental influence. After the calibration, the equivalent circuit for the MTJ device at high frequency can be set up, followed by the extraction procedure of the parasitic parameters of the high-frequency-equivalent-circuit. Combined with the extracted parameters, the equivalent circuit can be used for the simulation work with the MTJ device involved in the high-frequency operation. [ABSTRACT FROM AUTHOR]

The gut microbiota is reportedly involved in neurodegenerative disorders, and exploration of differences in the gut microbiota in different cognitive status could provide clues for early detection and intervention in cognitive impairment. Here, we used data from the Taizhou Imaging Study (N = 516), a community-based cohort, to compare the overall structure of the gut microbiota at the species level through metagenomic sequencing, and to explore associations with cognition. Interestingly, bacteria capable of producing short-chain fatty acids (SCFAs), such as Bacteroides massiliensis , Bifidobacterium pseudocatenulatum , Fusicatenibacter saccharivorans and Eggerthella lenta , that can biotransform polyphenols, were positively associated with better cognitive performance (p < 0.05). Although Diallister invisus and Streptococcus gordonii were not obviously related to cognition, the former was dominant in individuals with mild cognitive impairment (MCI), while the later was more abundant in cognitively normal (CN) than MCI groups, and positively associated with cognitive performance (p < 0.05). Functional analysis further supported a potential role of SCFAs and lactic acid in the association between the gut microbiota and cognition. The significant associations persisted after accounting for dietary patterns. Collectively, our results demonstrate an association between the gut microbiota and cognition in the general population, indicating a potential role in cognitive impairment. The findings provide clues for microbiome biomarkers of dementia, and insight for the prevention and treatment of dementia. • Associations between gut microbiota and cognition were assessed in a community population. • Six gut taxonomic features are associated with cognition. • SCFAs and lactic acid may correlate with better cognitive performance. • The significant associations persisted after accounting for dietary patterns. [ABSTRACT FROM AUTHOR]

Asymptomatic brain abnormalities are common incidental findings on brain MRI in the elderly population and can be regarded as imaging markers of early stroke and dementia. We initiated the Taizhou Imaging Study (TIS) to examine the prevalence and correlates of incidental findings using brain MRI among an elderly population residing in a rural area of China. A total of 562 individuals, at the age of 55 to 65 years, participated in the TIS study with a response rate of 90%. The prevalence of lacunes, white matter hyperintensity (WMH), cerebral microbleeds (CMB), perivascular space, and intracranial arterial stenosis was 26.69%, 10.68%, 18.51%, 27.76%, and 12.81%, respectively. Age and hypertension were the major correlates of these incidental findings. Per each year increase in age, the risks of WMH and CMB increased by 15% and 14%. Compared to individuals with normal blood pressure, individuals with hypertension had an increased risk of all incidental findings, with the adjusted odds ratios of 2.28 to 5.45. Correlations of age, gender and body mass index with brain gray matter fraction were also observed. The high prevalence of these findings indicates a need of preventative strategy to help prevent future stroke and dementia in this population. [ABSTRACT FROM AUTHOR]