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We propose a complete hardware-based architecture of multilayer neural networks (MNNs), including electronic synapses, neurons, and periphery circuitry to implement supervised learning (SL) algorithm of extended remote supervised method (ReSuMe). In this system, complementary (a pair of n- and p-type) memtransistors (C-MTs) are used as an electrical synapse. By applying the learning rule of spike-timing-dependent plasticity (STDP) to the memtransistor connecting presynaptic neuron to the output one whereas the contrary anti-STDP rule to the other memtransistor connecting presynaptic neuron to the teacher one, extended ReSuMe with multiple layers is realized without the usage of those complicated supervising modules in previous approaches. In this way, both the C-MT-based chip area and power consumption of the learning circuit for weight updating operation are drastically decreased comparing with the conventional single memtransistor (S-MT)-based designs. Two typical benchmarks, the linearly nonseparable benchmark XOR problem and Mixed National Institute of Standards and Technology database (MNIST) recognition have been successfully tackled using the proposed MNN system while impact of the nonideal factors of realistic devices has been evaluated.

A quad-band metamaterial absorber operating in the terahertz region is demonstrated in this paper. The basic cell of the device consists of three metallic strips (forming an asymmetric I-type resonator) placed on both layers of an insulating medium slab and a metallic ground plane. The asymmetric I-type resonator can interact strongly with the incident beam, resulting in four distinct absorption peaks with nearly 100% absorbance. The underlying mechanism of the quad-band absorption is investigated with the aid of their near-field distributions resulting from the calculation results of the numerical simulation. Results further prove that the four distinct absorption peaks exhibit large dependence on the dimension changes of the asymmetric I-type resonator (or three metallic strips). Based on this, we design a kind of terahertz metamaterial absorber which can effectively control the number of absorption peaks by replacing one of the metallic strips with photosensitive silicon. It is revealed that the number of absorption peaks can be adjusted from the dual-band to the quad-band when an external stimulus changes the conductivity of the photosensitive silicon. These absorption properties should have great application prospects in terms of thermal imaging, Raman enhancement, sensing and detection, etc.

Strain engineering is a promising method for tuning the electronic properties of two-dimensional (2D) materials, which are capable of sustaining enormous strain thanks to their atomic thinness. However, applying a large and homogeneous strain on these 2D materials, including the typical semiconductor MoS2, remains cumbersome. Here we report on a facile strategy for the fabrication of highly strained MoS2 via chalcogenide substitution reaction (CSR) of MoTe2 with lattice inheritance. The MoS2 resulting from the sulfurized MoTe2 sustains ultra large in-plane strain (approaching its strength limit ~10%) with great homogeneity. Furthermore, the strain can be deterministically and continuously tuned to ~1.5% by simply varying the processing temperature. Thanks to the fine control of our CSR process, we demonstrate a heterostructure of strained MoS2/MoTe2 with abrupt interface. Finally, we verify that such a large strain potentially allows the modulation of MoS2 bandgap over an ultra-broad range (~1 eV). Our controllable CSR strategy paves the way for the fabrication of highly strained 2D materials for applications in devices.

Along with the rapid development of flexible and wearable electronic devices, there have been a strong demand for flexible power sources, which has in turn triggered considerable efforts on the research and development of flexible batteries. An ideal flexible battery would have not only just high electrochemical performance but also excellent mechanical deformabilities. Therefore, battery constituent components, chemistry systems, device configurations, and practical applications are all pivotal aspects that should be thoroughly considered. Herein, we systematically and comprehensively review the fundamentals and recent progresses of flexible batteries in terms of these important aspects. Specifically, we first discuss the requirements for constituent components, including the current collector, electrolyte, and separator, in flexible batteries. We then elucidate battery chemistry systems that have been studied for various flexible batteries, including lithium-ion batteries, non-lithium-ion batteries, and high-energy metal batteries. This is followed by discussions on the device configurations for flexible batteries, including one-dimensional fiber-shaped, two-dimensional film-shaped, and three-dimensional structural batteries. Finally, we summarize recent efforts in exploring practical applications for flexible batteries. Current challenges and future opportunities for the research and development of flexible batteries are also discussed.

Greening of the railway energy supply chain is an irreversible trend, and photovoltaics (PVs) provide the most suitable type of renewable energy to integrate with railways. The integration of variable and uncertain PV power generation with the dynamic loads on a railway increases the flexibility needed to maintain load-generation balance. A new evolutionary model of a railway energy supply system (RESS) for railway PV integration systems (RPISs) is proposed by constructing a three-in-one “traction-storage-information integrated station” (TSIIS). A flexibility evaluation approach is proposed to estimate the system flexibility of both the individual TSIIS and the banded featured microgrid group through energy storage capacity configuration and dynamic scheduling via a multileader multifollower Stackelberg game. Finally, the Lanzhou-Xinjiang Railway is taken as an example to calculate the emission reduction and flexibility. The results show that through application of the storage configuration and scheduling strategy to the TSIIS network, the flexibility index of the Lanzhou-Xinjiang Railway increased by 8.40%, which promoted a corresponding decrease in carbon dioxide emissions and increase in PV permeability. In addition, with the gradual construction of PV and energy storage systems, an RPIS can basically achieve self-consistent energy utilization, offering environmental benefits and strong flexibility.

In order to improve the stock price prediction effect, based on the improved PSO algorithm, this paper constructs a stock price prediction model through neural network. Based on the idea of avoiding particles falling into the same local solution as much as possible and always keeping the particles with a certain diversity, in order to improve the global search ability of the algorithm in the early stage of evolution and the local search ability in the later stage of the evolution, the adaptive adjustment of inertial weight is proposed, and the algorithm is improved by combining with neural network. In addition, on the basis of the improved algorithm, this paper constructs a stock price prediction system based on neural network. Finally, this paper designs experiments to verify the function of the model from the perspectives of stock data collection and processing, and stock price prediction accuracy, and draw statistical graphs based on the statistical research results. The results of the research show that the system constructed in this paper has a certain practical effect.

The freezing pipe fracture can cause freezing wall to thaw and even lead to major accidents such as mine flooding easily, which seriously threatens the safety in construction. Therefore, scientific and effective comprehensive risk assessment for freezing pipe fracture is of great significance. In this work, a risk assessment method is put forward based on improved AHP-Cloud model with 19 evaluation indicators. First, the multi-dimension evaluation index system and evaluation model are established, on the basis of in-depth analysis of the risk factors that may lead to accidents. Second, synthesizing the normalization process and the improved analytic hierarchy process (AHP), the evaluation grade cloud and comprehensive evaluation cloud of freezing pipe fracture can be acquired by using the forward cloud generator. Finally, According to the max-subjection principle and the comprehensive evaluation method, we obtain the risk level of freezing pipe fracture. The model is applied to Yangcun Coal Mine. It has been verified that the risk assessment problem of freezing pipe fracture in freezing sinking can be successfully solved by the model we proposed. Above all, the study offers a new research idea for the risk management of freezing pipe fracture in freeze sinking.

BACKGROUND At present, the value of lipid indicators in evaluating the prognosis of colorectal cancer is still relatively limited. AIM To evaluate the value of a novel parameter for colorectal cancer (CRC) prognosis scoring based on preoperative serum lipid levels. METHODS Four key serum lipid factors, namely, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), apolipoprotein A1 (ApoA1), and apolipoprotein B (ApoB), were detected. Two representative ratios, HDL-C-LDL-C ratio (HLR) and ApoA1-ApoB ratio (ABR) were calculated. The relationship of these parameters with the prognosis of CRC patients including progression-free survival (PFS) and overall survival (OS) was analyzed by Kaplan-Meier plot and Cox proportional hazards regression. A novel lipoprotein cholesterol-apolipoprotein (LA) score based on HLR and ABR was established and its value in prognosis evaluation for CRC patients was explored. RESULTS Multivariate Cox proportional hazards regression analysis of PFS and OS showed that HDL-C, ApoA1, HLR, and ABR were positively associated with the prognosis of CRC patients. LA score was independently associated with a good prognosis in resectable CRC patients. Data processing of a dummy variable showed that the prognosis of patients with higher LA scores is better than that with lower LA scores. CONCLUSION The newly established LA score might serve as a better predictor of the prognosis of resectable CRC patients.

Miniaturized or microscale generators that can effectively convert weak and random mechanical energy into electricity have significant potential to provide solutions for the power supply problem of distributed devices. However, owing to the common occurrence of friction and wear, all such generators developed so far have failed to simultaneously achieve sufficiently high current density and sufficiently long lifetime, which are crucial for real-world applications. To address this issue, we invent a microscale Schottky superlubric generator (S-SLG), such that the sliding contact between microsized graphite flakes and n-type silicon is in a structural superlubric state (an ultra-low friction and wearless state). The S-SLG not only generates high current (~210 Am−2) and power (~7 Wm−2) densities, but also achieves a long lifetime of at least 5,000 cycles, while maintaining stable high electrical current density (~119 Am−2). No current decay and wear are observed during the experiment, indicating that the actual persistence of the S-SLG is enduring or virtually unlimited. By excluding the mechanism of friction-induced excitation in the S-SLG, we further demonstrate an electronic drift process during relative sliding using a quasi-static semiconductor finite element simulation. Our work may guide and accelerate the future use of S-SLGs in real-world applications., It is difficult to achieve high current density and long lifetime for micro generators owing to the common friction and wear. Here the authors invent a microscale Schottky superlubric generator to tackle this issue, reporting not only high current and power densities but also long lifetime of at least 5,000 cycles.

With the rapid development from traditional machine learning (ML) to deep learning (DL) and reinforcement learning (RL), dialog system equipped with learning mechanism has become the most effective solution to address human-machine interaction problems. The purpose of this article is to provide a comprehensive survey on learning-based human-machine dialog systems with a focus on the various dialog models. More specifically, we first introduce the fundamental process of establishing a dialog model. Second, we examine the features and classifications of the system dialog model, expound some representative models, and also compare the advantages and disadvantages of different dialog models. Third, we comb the commonly used database and evaluation metrics of the dialog model. Furthermore, the evaluation metrics of these dialog models are analyzed in detail. Finally, we briefly analyze the existing issues and point out the potential future direction on the human-machine dialog systems.

Background Anastomosis-related complications are common after the radical resection of colon cancer. Among such complications, severe stenosis or completely occluded anastomosis (COA) are uncommon in clinical practice, and the separation of the anastomosis is even rarer. For such difficult problems as COA or anastomotic separation, clinicians tend to adopt surgical interventions, and few clinicians try to solve them through endoscopic operations. Case presentation In this article, we present a case of endoscopic treatment of anastomotic closure and separation after radical resection for sigmoid carcinoma. After imaging examination and endoscopic evaluation, we found that the patient had a COA accompanied by a 3–4 cm anastomotic separation. With the aid of fluoroscopy, we attempted to use the titanium clip marker as a guide to perform an endoscopic incision and successfully achieved recanalization. We used a self-expanding covered metal stent to bridge the intestinal canal to resolve the anastomotic separation. Finally, the patient underwent ileostomy takedown, and the postoperative recovery was smooth. The follow-up evaluation results showed that the anastomotic stoma was unobstructed. Conclusions We reported the successful application of endoscopic technique in a rare case of COA and separation after colon cancer surgery, which is worth exploring and verifying through more clinical studies in the future.

Person identification plays a critical role in a large range of applications. Recently, RF based person identification becomes a hot research topic due to the contact-free nature of RF sensing that is particularly appealing in current COVID-19 pandemic. However, existing systems still have multiple limitations: i) heavily rely on the gait patterns of users for identification; ii) require a large amount of data to train the model and also extensive retraining for new users and iii) require a large frequency bandwidth which is not available on most commodity RF devices for static person identification. This paper proposes RF-Identity, an RFID-based identification system to address the above limitations and the contribution is threefold. First, by integrating walking pattern features with unique body shape features (e.g., height), RF-Identity achieves a high accuracy in person identification. Second, RF-Identity develops a data augmentation scheme to expand the size of the training data set, thus reducing the human effort in data collection. Third, RF-Identity utilizes the tag diversity in spatial domain to identify static users without a need of large frequency bandwidth. Extensive experiments show an identification accuracy of 94.2% and 95.9% for 50 dynamic and static users, respectively.

Vienna rectifiers are widely used because of their advantages of high power-factor, low voltage stress on the power semiconductor switches, high power density, stable output voltage, low current harmonic content, and good economics. And gradually applied to the front stage AC/DC part of the electric vehicle charger. Traditional Vienna rectifier control methods include double closed-loop control, hysteresis current control, and Sliding mode variable structure control strategy, but all strategies usually regulate DC-Voltage and keep the unity power factor. However, if it is used for the interface part of the electric vehicle charger with frequent load switching, it is necessary not only to ensure the stability of the output voltage and low THD of the current, but also to be able to respond to the fluctuation of the voltage and frequency of the power system and improve the inertia and damping at the interface. Thereby, the stability of the power grid is improved to a certain extent, and fast-charging is ensured while being grid-friendly. Therefore, this paper proposes to apply the virtual synchronous motor control to the Vienna rectifier to improve the adaptability of the grid to the large-scale access of electric vehicles. Build the topology of the Vienna rectifier in simlink and the modulation method using SVPWM to build a complete model on the basis of VSM.

In recent years, flexible/stretchable batteries have gained considerable attention as advanced power sources for the rapidly developing wearable devices. In this article, we present a critical and timely review on recent advances in the development of flexible/stretchable batteries and the associated integrated devices. We first provide an overview on the requirements for flexible or stretchable batteries. This is followed by the design and development strategies for free-standing flexible/stretchable electrodes. We then summarize the recent developments of flexible/stretchable electrolytes and separators as the key battery components as well as various flexible/stretchable batteries and their integrated devices. Finally, the current challenges and future perspectives in this emerging field of flexible/stretchable batteries are also discussed.

China has been the main source of global energy consumption growth for 18 years in a row. Railways account for a large proportion of China's energy consumption, and the greening of railway energy supply systems will be an irreversible trend over time. Using a SWOT analysis approach, the authors investigate the internal strengths and weaknesses and the external opportunities and threats for orchestrated development of a solar railway system in China. After discussing countermeasures and suggestions for integrated development of a solar railway system in China, the conclusion is drawn that the railway power system will be green, resilient, self-contained and sustainable by utilising the existing space in the railway system for photovoltaic power generation, using hybrid energy storage facilities and energy internet technologies to balance power supply and railway energy demands, and grasping the strategic opportunity for domestic and foreign construction projects.

Summary Smoking is mainly sustained by nicotine dependence (ND), which varies across ethnic groups principally due to genetic as well as environmental factors. The Fagerström Test for Nicotine Dependence (FTND) and biomarkers of tobacco exposure are two important approaches to assess ND. However, the relationship between ND and FTND of Chinese smokers has not been studied. The aim of this study was to assess the relationship between FTND scores and nicotine, cotinine, 3′-hydroxycotinine (3HC) and nicotine metabolite ratio (NMR, the concentration ratio of 3HC to cotinine) in Chinese smokers. FTND was carried out and general characteristics were collected using a self-administered smoking questionnaire with 289 smokers. Nicotine, cotinine and 3HC in urine were simultaneously determined by liquid chromatography–mass spectrometry/mass spectrometry (LC-MS/MS). The concentrations of nicotine, cotinine and 3HC in the urine of smokers with a high FTND score were higher than in the urine of those with a low FTND score. There were significant correlations between urinary biomarker and FTND scores. Except for FTND item 2 (difficulty to refrain), the other items showed significant associations with the urinary biomarkers. No relationship was found between the nicotine metabolite ratio (NMR, 3′-hydroxycotinine/cotinine) and FTND scores or general characteristics of the participants. In conclusion, biomarkers of tobacco exposure levels are significantly associated with FTND scores. However, FTND Item 2 and NMR were not found to be associated with nicotine dependence in Chinese smokers.

For the immense requirement on agriculture and animal husbandry, application of pesticides and veterinary drugs had become a normal state in the farming and ranching areas. However, to intently pursue the yields, large quantities of residues of pesticides and veterinary drugs have caused serious harm to both the environment and the food industry. To control and solve such an issue, a variety of novel techniques were developed in recent years. In this review, the development and features about point-of-care-testing (POCT) detection on the residues of pesticides and veterinary drugs, such as, electrochemistry (EC), enzyme-linked immunosorbent assay (ELISA) and nano-techniques, were systematically introduced. For each topic, we first interpreted the strategies and detailed account of such technical contributions on detection and assessment of the residues. Finally, the advantages and perspectives about mentioned techniques for ultrasensitive assessment and sensing on pesticides and veterinary drugs were summarized.

BACKGROUND The stromal vascular fraction can improve volume retention after fat grafting, but the optimal stromal vascular fraction extraction method remains controversial. This study investigated the effect of mechanical vibration on stromal vascular fraction activity and explored the efficacy of vibration as a new extraction method compared to centrifugation, enzyme digestion, and nanoemulsion methods. METHODS Twenty-four rabbits were divided into three groups, and adipose tissue was harvested from the scapular region of each rabbit. In the first group, stromal vascular fraction was extracted from adipose tissue by vibration with different frequencies and durations. Cell counts and colony formation were assessed to determine the optimal vibration parameters. In the second group, stromal vascular fraction was extracted by the four methods, and the cell counts, proliferation, and adipogenic capabilities were observed in vitro. In the third group, adipose tissue mixed with stromal vascular fraction extracted by means of the four methods was grafted into rabbit ears. Volume retention and histologic changes were evaluated over 24 weeks. RESULTS Stromal vascular fraction activity was not influenced by low-frequency (≤45 Hz) and short-duration (≤20 minutes) vibrations. Vibration at 30 Hz for 15 minutes was most efficient for stromal vascular fraction extraction. In vitro, stromal vascular fraction extracted by vibration showed advantages for cell viability. In vivo, the vibration group showed a more normal tissue morphology and a higher retention rate (60.68 ± 7.07 percent) than the enzyme digestion (31.88 ± 4.99 percent), centrifugation (43.76 ± 4.32 percent), and nanoemulsion groups (21.79 ± 3.57 percent) (p < 0.05). CONCLUSION Vibration at 30 Hz for 15 minutes is recommended as a novel nonenzymatic method to extract stromal vascular fraction with high activity.

Photovoltaic power generation application with advantages of sustainability and low emission is limited on its low photovoltaic (PV) efficiency mainly due to high panel temperature. In this paper, a solar photovoltaic system coupled by ground heat exchangers (PV-GHEs system) is proposed to reduce the operation temperature of panels and keep a high PV efficiency. Taking Tikanlik with typical arid climate of northwestern China as an example, a numerical model based on the software TRNSYS is built and its reliability are validated based on an actual thermal response test data. The simulation results show that the PV-GHEs system can reduce the panel temperature by 26.8% and increase the annual electricity yield by 7.9%, compared with conventional PV systems. Sensitivity analysis highlights the influences of environmental, geological and design parameters on the system performance. For the long-term operation, a gradually growing ground temperature is unfavorable and may weaken the heat transfer between GHEs and the surrounding ground. For the case of Tikanlik, the growing rate of the ground temperature is 0.67 °C per year and a minimum distance of 10 m between boreholes is recommended when more GHEs are needed. Finally, a life cycle cost analysis of the PV-GHEs system is investigated.

Objective: To study the value of magnetic resonance imaging (MRI) in the diagnosis of nasopharyngeal carcinoma with pericranial infiltration. Methods: 86 patients with nasopharyngeal carcinoma were selected as the research objected and examined by MRI and clinical examination, and the results of the two methods were compared. Results: In MRI examination, the positive rate of cranial nerve infiltration in nasopharyngeal carcinoma was 23.26%, which was significantly higher than 8.13% in clinical diagnosis. The coincidence rate between clinical diagnosis and MRI diagnosis was 35.00%. Conclusion: Nuclear MRI has important application value in the diagnosis of cranial nerve infiltration of nasopharyngeal carcinoma, which is worthy of clinical promotion.

An approach to realize a multiple-band perfect light absorber is demonstrated using a simple metamaterial design featuring a composite metallic structure consisting of a closed ring and a rectangular patch atop a metallic substrate separated by an insulator. Three narrow-band and discrete resonance peaks with nearly 100% absorption rates are obtained. The first absorption peak is due to the dipole resonance of the closed ring, while the last two absorption peaks are caused by the coupling effect of the closed ring and rectangular patch. The field distribution of the three absorption peaks is given to provide additional evidence. Unlike traditional multiple-band light absorbers that eliminate (or avoid) the interaction between the metallic array structures, our design is based on the mode coupling of the composite structure. This method can obviously reduce the number of metallic resonators, simplify the structure design and reduce fabrication costs.

Multiple-band metamaterial absorbers as an important branch of metamaterial-based resonant devices have shown considerable application prospects in real life. However, current designs have many shortcomings in the realization of multiple-band absorption, including complex pattern structure, time-consuming fabrication steps, and strong interaction between sub-elements. Herein, a simple design of multiple-band metamaterial absorber based on single metallic resonator is presented. Basic cell of the multiple-band absorption is formed by a square metallic patch (cut by a concentric air gap) placed on a metallic mirror separated by an insulating medium material. The metamaterial structure can interact strongly with the incident beam to produce the fundamental mode resonance, third-order resonance, and two other resonances resulted from the concentric air gap introduction. The combining effect of the four discrete resonance modes provides the ability to achieve quad-band absorption. The quad-band absorption shows great dependence on the structure dimensions. Based on this, we further design a kind of multiple-band absorption having the adjustable number of absorption peaks by introducing photosensitive silicon material in the initial area of the air gap. The number of resonance peaks can be tuned flexibly from quad-band absorption to dual-band absorption by changing the conductivity (i.e., material property) of photosensitive silicon material.

A 2-year field experiment was carried out to determine the combined effects of planting density and N application rate on the agronomic, economic and environmental benefits of maize production. We set three planting densities (67,500, 75,000 and 82,500 plants ha−1) and five N application rates (0, 100, 200, 300 and 400 kg N ha−1). Increasing planting density improved water use and N uptake, but reduced nitrate in soil. More N inputs over optimal rates decreased NUE and increased nitrate in soil. Compared to the modelling combination of planting density and N application rate that achieved the maximum yield and profit, the modelling combination that achieved the maximum net productive value retained yield and profit, but it used an N application rate that was 12–20% lower, and resulted in an 11–25% decrease in nitrate in soil. The optimal modelling combinations, which were a planting density of 74,387 plants ha−1 and an N application rate of 302 kg N ha−1 in 2017, and 73,528 plants ha−1 and 311 kg N ha−1 in 2018, achieved the maximum net productive values of 2620 $ ha−1 in 2017 and 2693 $ ha−1 in 2018. When the combinations maximized yield and profit, the environmental effect was more sensitive than that of the yield and profit. The optimal combination of planting density and N application rate curtailed N pollution without the great cost of yield and profit, which balanced the agronomic and environmental effect on maize production.

Recently, increasing numbers of oil and gas reservoirs have been discovered in the Wenchang Depression, western Pearl River Mouth Basin, South China Sea, revealing prospects for hydrocarbon exploration. The Enping Formation (E3e) is a key target layer for the development of source rocks. However, previous work has only focused on lacustrine swamp source rocks of E3e in the Wenchang A Sag, without a systematic study of shallow lacustrine source rocks. In this study, the quality of E3e shallow lacustrine source rocks is reevaluated, and the hydrocarbon generation and expulsion characteristics are analyzed using relevant geological data and constructing a conceptual model. The results show that the E3e2 source rocks have greater thickness (50–600 m) and similar organic matter abundance (0.5–2.5%) compared with the E3e1 source rocks (50–500 m and 0.5–2.5%). On the whole, the E3e source rocks were deposited in the continental environment and are dominated by Type II and Type III kerogen. Meanwhile, the E3e source rocks of the Wenchang A Sag are in the stage of mature to over mature, while those of the Wenchang B Sag are in the stage of low mature. Vertically, the hydrocarbon generation potential of the E3e2 source rocks is greater than E3e1. Also, the cumulative hydrocarbon production of steep slope in the Wenchang A Sag is larger than that in the Wenchang B Sag. In addition, the corresponding vitrinite reflectances of hydrocarbon expulsion threshold and peak are 0.72 and 0.96%, respectively. Horizontally, four hydrocarbon generation and expulsion centers were mainly concentrated in different subsags of the Wenchang A and B Sags for E3e. The maximum values of hydrocarbon generation and expulsion intensity for E3e1 are 1500 × 104 t/km2 and 1000 × 104 t/km2, respectively, while those for E3e2 are 1800 × 104 t/km2 and 1200 × 104 t/km2, respectively, with the expulsion efficiency of 75%.

In recent years, probiotics have been increasingly proposed as health-promoting supplements in variety of food systems because of their physiological function and technological characteristics. Tho...

Background:. The association between heart rate and 1-year clinical outcomes in heart failure (HF) patients with atrial fibrillation (AF), and whether this association depends on left ventricular ejection fraction (LVEF), are unclear. We investigated the relationship between discharge heart rate and 1-year clinical outcomes after discharge among hospitalized HF patients with AF, and further explored this association that differ by LVEF level. Methods:. In this analysis, we enrolled 1760 hospitalized HF patients with AF from the China Patient-centered Evaluative Assessment of Cardiac Events Prospective Heart Failure study from August 2016 to May 2018. Patients were categorized into three groups with low (

Background: The use of direct oral anticoagulants (DOACs) is recommended as the preferred treatment drug in patients with nonvalvular atrial fibrillation (AF). However, the effectiveness and safety of DOACs compared with vitamin K antagonists (VKAs) in patients with cancer and AF are still controversial. Therefore, we performed a meta-analysis regarding the effectiveness and safety of DOACs vs. VKAs in AF patients with cancer.Methods: A search of the Pubmed and EMBASE databases until August 2021 was performed. Adjusted risk ratios (RRs) and 95% confidence intervals (CIs) were pooled using a random-effects model with an inverse variance method.Results: Thirteen studies were deemed to meet the criteria. For the effectiveness outcomes, the use of DOACs compared with VKAs use was significantly associated with decreased risks of stroke or systemic embolism (RR = 0.66, 95% CI: 0.54–0.80) and venous thromboembolism (RR = 0.40, 95% CI: 0.26–0.61), but not ischemic stroke (RR = 0.79, 95% CI: 0.56–1.11), myocardial infarction (RR = 0.78, 95% CI: 0.56–1.11), cardiovascular death (RR = 0.76, 95% CI: 0.53–1.09), and all-cause death (RR = 0.82, 95% CI: 0.43–1.56). For the safety outcomes, compared with VKAs use, the use of DOACs was associated with reduced risks of intracranial bleeding (RR = 0.60, 95% CI: 0.50–0.71) and gastrointestinal bleeding (RR = 0.87, 95% CI: 0.80–0.95). There were no significant differences in major bleeding (RR = 0.87, 95% CI: 0.74–1.04), major or nonmajor clinically relevant bleeding (RR = 0.87, 95% CI: 0.74–1.01), and any bleeding (RR = 0.88, 95% CI: 0.76–1.03).Conclusion: Compared with VKAs, DOACs appeared to have significant reductions in stroke or systemic embolism, venous thromboembolism, intracranial bleeding, and gastrointestinal bleeding, but comparable risks of ischemic stroke, myocardial infarction, cardiovascular death, all-cause death, major bleeding, major or nonmajor clinically relevant bleeding, and any bleeding in patients with AF and cancer.

Beamforming can improve the communication and sensing capabilities for a wide range of IoT applications. However, most existing IoT devices cannot perform beamforming due to form factor, energy, and cost constraints. This paper presents RFlens, a reconfigurable metasurface that empowers low-profile IoT devices with beamforming capabilities. The metasurface consists of many unit-cells, each acting as a phase shifter for signals going through it. By encoding the phase shifting values, RFlens can manipulate electromagnetic waves to "reshape" and resteer the beam pattern. We prototype RFlens for 5 GHz Wi-Fi signals. Extensive experiments demonstrate that RFlens can achieve a 4.6 dB median signal strength improvement (up to 9.3 dB) even with a relatively small 16 × 16 array of unit-cells. In addition, RFlens can effectively improve the secrecy capacity of IoT links and enable passive NLoS wireless sensing applications.

Background: Recent observational studies have compared effectiveness and safety profiles between non-vitamin K antagonist oral anticoagulants (NOACs) and warfarin in patients with atrial fibrillation (AF). Nevertheless, the confounders may exist due to the nature of clinical practice-based data, thus potentially influencing the reliability of results. This systematic review and meta-analysis were conducted to compare the effect of NOACs with warfarin based on the propensity score-based observational studies vs. randomized clinical trials (RCTs).Methods: Articles included were systematically searched from the PubMed and EMBASE databases until March 2021 to obtain relevant studies. The primary outcomes were stroke or systemic embolism (SSE) and major bleeding. Hazard ratios (HRs) and 95% confidence intervals (CIs) of the outcomes were extracted and then pooled by the random-effects model.Results: A total of 20 propensity score-based observational studies and 4 RCTs were included. Compared with warfarin, dabigatran (HR, 0.82 [95% CI, 0.71–0.96]), rivaroxaban (HR, 0.80 [95% CI, 0.75–0.85]), apixaban (HR, 0.75 [95% CI, 0.65–0.86]), and edoxaban (HR, 0.71 [95% CI, 0.60–0.83]) were associated with a reduced risk of stroke or systemic embolism, whereas dabigatran (HR, 0.76 [95% CI, 0.65–0.87]), apixaban (HR, 0.61 [95% CI, 0.56–0.67]), and edoxaban (HR, 0.58 [95% CI, 0.45–0.74]) but not rivaroxaban (HR, 0.92 [95% CI, 0.84–1.00]) were significantly associated with a decreased risk of major bleeding based on the observational studies. Furthermore, the risk of major bleeding with dabigatran 150 mg was significantly lower in observational studies than that in the RE-LY trial, whereas the pooled results of observational studies were similar to the data from the corresponding RCTs in other comparisons.Conclusion: Data from propensity score-based observational studies and NOAC trials consistently suggest that the use of four individual NOACs is non-inferior to warfarin for stroke prevention in AF patients.

Background: To evaluate the safety and effectiveness of endoscopic technique in treating postoperative anastomotic complications of digestive tract. Methods: Clinical data of patients received endoscopic treatment in our hospital due to anastomotic complications after gastrointestinal surgery from January 2015 to December 2018 were collected for retrospective analysis. Endoscopic intervention was used for postoperative anastomotic complications in all the included cases. The time of the intervention measures, laboratory examination, incidence of complications and postoperative follow-up were observed and analyzed.Results: A total of 88 patients were included in the study, including 43 patients with anastomotic stenosis,22 with anastomotic obstruction,23 with anastomotic fistula. For anastomotic obstruction patients, 36 patients with anastomosis were successfully treated with endoscopy. For anastomotic obstruction patients, 18 cases were successfully treated with endoscopy. For anastomotic fistula patients, 21 cases were successfully treated with endoscopy.During follow-up after the endoscopic procedure, 4 patients with anastomotic stenosis needed endoscopic intervention again, 3 cases undertook surgical intervention and 2 cases maintained acceptable defecation function by intermittent dilation with a plastic dilater. one patients with anastomotic obstruction had stent displacement and was removed. For the anastomotic fistula patients,one case relapsed and then underwent endoscopic intervention again, three cases converted to surgical intervention.Preoperative and postoperative blood biochemical examination had no significant statistical significanceConclusion: Endoscopic treatment of anastomosis complications was effective for some of the patients, especially for those with anastomosis stenosis or stricture, considering its saftey, it might be the first choice for anastomosis complications.

Terahertz video SAR can perform high-resolution imaging of targets in a short period of time, which is conducive to detection and tracking of ground moving targets. A new method is proposed in this paper for moving target shadow detection and tracking, which is verified on terahertz band data for the first time. According to the specific characteristics of terahertz video SAR images, this method is realized by change detection through background modeling and image difference. In the experiment, the effectiveness of proposed method is verified by the terahertz video-SAR images.

Video synthetic aperture radar (ViSAR) is regarded as an effective sensor to monitor moving targets continuously. In addition to realize video imaging, W-band radar’s high scattering characteristics on smooth roads create conditions for the formation of shadows for moving targets. This paper reports the video imaging results of an UAV borne W-band SAR on urban intersection and analyzes the shadows of moving targets. A simple speed estimation method is proposed based on the shadow model.

Although good performance has been reported in shallow neural networks, the application of memristor synapses towards realistic deep neural networks has met more stringent requirements on the synapse properties, particularly the high precision and linearity of the synaptic analog weight tuning. In this study, a LiAlOX memristor synapse was fabricated and optimized to address these demands. By delicately tuning the initial conductance states, 120-level continuously adjustable conductance states were obtained and the nonlinearity factor was substantially reduced from 8.96 to 0.83. The significant enhancements were attributed to the reduced Schottky barrier height (SBH) between the filament tip and the electrode, which was estimated from the measured I-V curves. Furthermore, a deep neural network for realistic action recognition task was constructed, and the recognition accuracy was found to be increased from 15.1% to 91.4% on the Weizmann video dataset by adopting the above-described device optimization method.

As a major challenge and opportunity for traditional manufacturing, intelligent manufacturing is facing the needs of sustainable development in future. Sustainability assessment undoubtedly plays a pivotal role for future development of intelligent manufacturing. Aiming at this, the paper presents the digital twin driven information architecture of sustainability assessment oriented for dynamic evolution under the whole life cycle based on the classic digital twin mapping system. The sustainability assessment method segment of the architecture includes indicator system building, indicator value determination, indicator importance degree determination and intelligent manufacturing project assessing. A novel approach for treating the ambiguity of expert judgment in indicator value determination by introducing trapezoidal fuzzy number into analytic hierarchy process is proposed, while the complexity of the influence relationship among the indicators is processed by the integration of complex networks modeling and PROMETHEE II for the indicator importance degree determination. A two-stage evidence combination model based on evidence theory is built for intelligent manufacturing project assessing lastly. The presented digital-twin-driven information architecture and the sustainability assessment method is tested and validated on a study of sustainability assessment of 8 intelligent manufacturing projects of an air conditioning enterprise. The results of the presented method were validated by comparing them with the results of the fuzzy and rough extension of the PROMETHEE II, TOPSIS and VIKOR methods, indicator importance degree determining method by entropy and indicator value determining method by accurate expert scoring. Funding Agencies|National Natural Science Foundation of ChinaNational Natural Science Foundation of China (NSFC) [51875251, 51765001]; Guangdong Special Support Talent Program-Innovation and Entrepreneurship Leading Team [2019BT02S593]; 2018 Guangzhou Leading Innovation Team Program (China) [201909010006]; Ningxia Natural Science Foundation [2020AAC03202, NZ17111]; Third Batch of Ningxia Youth Talents Supporting Program [TGJC2018048]; Blue Fire Project (Huizhou) Industry-University-Research Joint Innovation Fund of the Ministry of Education (China) [CXZJHZ201722]

This thesis investigates a novel solar-assisted heat pump integrated phase change energy storage system. The defrosting performance of this system was studied experimentally and the results were compared with two traditionally used methods: reverse cycle defrosting (RCD) method and hot gas bypass defrosting (HGBD) method. The results show that the phase change energy storage system has superior performance compared with traditional defrosting methods. The indoor temperature drop recorded was relatively small and the defrosting time was 75% of the RCD system and 53% of HGBD system. The phase change energy storage system increased the condensation temperature which consequently increased the temperature difference of heat transfer resulting in higher conductivity in the defrosting progress. Compared with the method of RCD and the method of HGBD, the recovery time of the system was shortened by 90 and 160 seconds, respectively. The system works with low-temperature heat source and circulating water, which considerably reduces energy consumption, thereby improving the performance of the defrosting system. A further experimental study was also conducted on the heating performance and the results also indicated that the value of COP can reach up to 3.6 in daytime, and the indoor temperature can be stably maintained above 18°C throughout the day.

Objective: Study the effect of electroacupuncture on permenopausal depressive disorder (PDD) model through the peri-menopausal depression model mice. Methods: KM female mice were selected. Except for the blank group (BG), the other groups of mice were removed by castration method. The mice of PDD was prepared by combining chronic unpredictable stimulation. Mice in the model group (MG) were not treated and fed normally. The western medicine group (WG) was given the corresponding drug for treatment. The electroacupuncture group (EAG) was given the electroacupuncture for treatment, and consecutive for 28 days. The levels of T, E2, FSH and LH in serum of mice were measured, and the brain tissue of 5-HT, DA and NE level were measured. Through the HE staining observed the morphological changes of mice hypothalamus. Results: Compared with MG, EAG could increase the number of spontaneous activities of PDD model mice, the level of T, E2 in serum and the level of 5-HT, DA, NE in brain tissue was improved, and the level of FSH, LH in serum was reduced, and the hypothalamic lesions was improved. Conclusion: Electroacupuncture could improve the activity and memory of PDD mice, adjust the disorder of sex hormone, and increased the levels of monoamine transmitters (5-HT, NE, DA), and it could effectively improve the behavior and related biochemical indexes of PDD, and thus play an important therapeutic role. Keywords: PDD, Electroacupuncture, Behavior indexes, Biochemical indexes, Histopathologic morphology

With the reformation of energy market and the development of energy intelligent technology, regional integrated energy system, as an important direction of energy system development, is tending to play an important role in the field of energy supply and demand response program. This paper presents an optimal operation model of an integrated energy system considering the response of energy price. In this paper, the typical structure of the integrated energy system and the model of each system module are first introduced in detail, and the system model presented includes three subsystems: power supply, heating, and cooling. Second, a complete scheduling scheme is built based on the energy consumption characteristics and system operation characteristic of the integrated energy system. The model presented could reduce the cost of system without causing a significant amount of environmental pollutions, and improve the energy efficiency of the system efficiently. Besides, the scheduling strategy proposed could also provide support for the operation strategy of the integrated energy system under the energy development.

As an emerging two-dimensional semiconductor, Bi2O2Se has recently attracted broad interests in optoelectronic devices for its superior mobility and ambient stability, whereas the diminished photoresponse near its inherent indirect bandgap (0.8 eV or λ = 1550 nm) severely restricted its application in the broad infrared spectra. Here, we report the Bi2O2Se nanosheets based hybrid photodetector for short wavelength infrared detection up to 2 μm via PbSe colloidal quantum dots (CQDs) sensitization. The type II interfacial band offset between PbSe and Bi2O2Se not only enhanced the device responsivity compared to bare Bi2O2Se but also sped up the response time to ∼4 ms, which was ∼300 times faster than PbSe CQDs. It was further demonstrated that the photocurrent in such a zero-dimensional-two-dimensional hybrid photodetector could be efficiently tailored from a photoconductive to photogate dominated response under external field effects, thereby rendering a sensitive infrared response >103 A/W at 2 μm. The excellent performance up to 2 μm highlights the potential of field-effect modulated Bi2O2Se-based hybrid photodetectors in pursuing highly sensitive and broadband photodetection.

Previous studies have provided established evidence on adverse outcomes of the coadministration of proton pump inhibitors (PPIs) and clopidogrel, whereas cerebro-cardiovascular outcomes of PPI use in the absence of clopidogrel therapy remain controversial.In this study, we aimed to assess the association between PPIs and cerebro-cardiovascular outcomes independent of clopidogrel.Systematic searches were conducted in the Cochrane Library, PubMed, and Embase databases for all relevant studies up to August 2018. Odds ratios (ORs) with its 95% confidence intervals (CIs) were abstracted and pooled using the random-effects model.A total of 14 observational studies (13 cohort studies and 1 case-control study) were identified. Compared with non-PPI users, PPI users experienced higher risks of stroke (OR: 1.22, 95% CI: 1.08-1.36), myocardial infarction (MI; OR: 1.23, 95% CI: 1.14-1.32), cardiovascular death (OR: 1.83, 95% CI: 1.69-1.98), and major adverse cardiovascular events (MACEs; OR: 1.22, 95% CI: 1.05-1.40) independent of clopidogrel use, but not all-cause death (OR: 1.50, 95% CI: 0.99-2.25). In the subgroup analysis, PPI alone was associated with significant risks of new-onset MI (OR: 1.23, 95% CI: 1.13-1.35) and stroke (OR: 1.17, 95% CI: 1.05-1.30) in patients without previous MI or stoke and recurrent MI (OR: 1.24, 95% CI: 1.02-1.51) and stroke (OR: 1.36, 95% CI: 1.19-1.55) risks in patients with a previous MI.Based on current publications, PPI use seems to be associated with increased risks of stroke, MI, cardiovascular death, and MACEs independent of clopidogrel. Greater caution should be therefore exercised while considering its clinical benefits and further investigate any causal relationships.

Ferroelectric engineered pn doping in two-dimensional (2D) semiconductors hold essential promise in realizing customized functional devices in a reconfigurable manner. Here, we report the successful pn doping in molybdenum disulfide (MoS2) optoelectronic device by local patterned ferroelectric polarization, and its configuration into lateral diode and npn bipolar phototransistors for photodetection from such a versatile playground. The lateral pn diode formed in this way manifests efficient self-powered detection by separating ~12% photo-generated electrons and holes. When polarized as bipolar phototransistor, the device is customized with a gain ~1000 by its transistor action, reaching the responsivity ~12 A W−1 and detectivity over 1013 Jones while keeping a fast response speed within 20 μs. A promising pathway toward high performance optoelectronics is thus opened up based on local ferroelectric polarization coupled 2D semiconductors., Photodetectors based on two dimensional (2D) materials still suffer from low performance. Here, the authors tackle this issue by introducing a reconfigurable design enabled by locally tuning the doping of a 2D molybdenum disulfide film through the polarization of an underlying ferroelectric material.

Objective To evaluate the pharmacological characteristics of SU-011, a novel sodium-dependent glucose co-transporter 2 (SGLT2) inhibitor. Methods The in vitro activities of SU-011 were investigated in cell-based assays. The urinary glucose excretion, glucose tolerance and the risk of hypoglycaemia were evaluated in mice. Moreover, the dose–response relationship and chronic pharmacological studies of SU-011 were assessed in streptozotocin (STZ)-induced diabetic model, a STZ-treated model with impaired insulin secretion. Key findings SU-011 is a potential SGLT2 inhibitor with 5.6 nm inhibitory activity for SGLT2 and 1137-fold selectivity for SGLT1. In healthy mice, SU-011 improves the tolerance to a glucose load and promotes the urinary glucose excretion. Besides, SU-011 (10 mg/kg) still exhibited less risk of hypoglycaemia. During chronic treatment, SU-011 exhibited sustained glucose-lowering effect without the side effect of weight gain in STZ-induced diabetic mice. The levels of non-fasting and fasting plasma glucose, glycosylated haemoglobin, food and water intake were significantly decreased in SU-011-treated group. Moreover, SU-011 decreases the plasma levels of interleukin-1β, tumour necrosis factor-α and C-reactive protein even better than that of dapagliflozin. Conclusions All of these results indicated that SU-011 may be effective for the management of diabetes.

By exploiting novel transport phenomena such as ion selectivity at the nanoscale, it has been shown that nanochannel systems can exhibit electrically controllable conductance, suggesting their potential use in neuromorphic devices. However, several critical features of biological synapses, particularly their conductance modulation, which is both memorable and gradual, have rarely been reported in these types of systems due to the fast flow property of typical inorganic electrolytes. In this work, we demonstrate that electrically manipulating the nanochannel conductance can result in nonvolatile conductance tuning capable of mimicking the analog behavior of synapses by introducing a room-temperature ionic liquid (IL) and a KCl solution into the two ends of a nanochannel system. The gradual conductance-tuning mechanism is identified through fluorescence measurements as the voltage-induced movement of the interface between the immiscible IL and KCl solution, while the successful memorization of the conductance tuning is ascribed to the large viscosity of the IL. We applied a nanochannel-based synapse to a handwritten digit-recognition task, reaching an accuracy of 94%. These promising results provide important guidance for the future design of nanochannel-based neuromorphic devices and the manipulation of nanochannel transport for computing.

Background Previous studies have suggested that metabolic syndrome (MetS) and its component conditions are linked to the development of many benign or malignant diseases. Some studies have described relationships among metabolic syndrome or diabetes and liver cancer, but not many articles described the relationships between MetS and cirrhosis, acute hepatic failure, end-stage liver disease, and even death. However, liver cancers, cirrhosis, acute hepatic failure, end-stage liver disease, and liver-related mortality—collectively described as liver-related events (LREs)—may have different relationships with MetS. We undertook this meta-analysis to examine the association between MetS and LREs, and to determine whether geographic region or hepatitis B virus (HBV) positivity might influence the association. Methods Relevant studies were identified from PubMed, EMBASE, and the Cochrane database. Two reviewers independently searched records from January 1980 to December 2017. The search terms included ‘metabolic syndrome’, ‘diabetes mellitus’, ‘insulin resistance syndrome’, and ‘metabolic abnormalities’, combined with ‘cirrhosis’, ‘hepatic fibrosis ’, ‘hepatocellular carcinoma’, ‘complication’, ‘LRE’, ‘HCC’, ‘liver-related events’, and ‘liver cancer’. No language restriction was applied to the search. We chose the studies reporting an association between MetS and LREs. We used Begg’s and Egger’s tests and visually examined a funnel plot to assess publication bias. All analyses were conducted in Stata 14.0 software. Results There were 19 studies (18 cohort and 1 case-control) included in the analysis, with a total of 1,561,457 participants. The subjects’ ages ranged from 18 to 84 years. The combined analysis showed an overall 86% increase risk of LREs in cases with MetS (RR: 1.86,95% CI: 1.56–2.23). The funnel plot was asymmetrical, and the Egger’s test p values showed a publication bias in this meta analysis. However, through the trim and fill method, we obtained a new RR value for LREs with MetS of 1.49 (95% CI: 1.40–1.58, p = 0.000). There was no obvious difference with the two answers, so we concluded that the results were robust. For hepatitis B positive patients, the RR for MetS and LREs was 2.15 (95% CI:1.02–4.53, p = 0.038), but for the hepatitis B negative patients, the RR was 1.85 (95% CI:1.53–2.24, p = 0.000). And for non-Asians, the RR for MetS and LREs was 2.21 (95% CI: 1.66–2.69, p = 0.000), while for Asians, the RR was 1.73 (95% CI: 1.35–2.22, p = 0.000). Conclusions This meta-analysis showed that MetS is associated with a moderately increased risk of LREs prevalence. Patients with MetS together with hepatitis B are more likely to develop hepatic events. For non-Asians, MetS is more likely to increase the incidence of LREs.

Two high concentrating solar systems have been established with dish concentrator and plane-mirrors array concentrator. In the paper, the thermal performance has been experimentally studied with jet water cooling device and flat microchannel water-cooled device. The experimental results show that the maximum surface temperature difference of the dish concentrating system is greater than 20°C, while the plane-mirrors array system is lower than 4°C. It indicates that the plane-mirrors array concentrator has better uniformity. As the concentration ratio increases, the electrical efficiency of the concentrating photovoltaic system gradually decreases. When the concentration ratio is 200, the electrical efficiency of the photovoltaic system is 25%. The concentration ratio of 500 times or less is considered to be a suitable value, and then the electrical efficiency can still exceed 20%. It is found that the plane-mirrors array solar system is more suitable for the photovoltaic system than dish type system, which is only suitable for thermal power generation system.

This paper presents a two-stage optimization method for a coupled capacity planning and operation problem, cast within the economical operation of Regional Integrated Energy System. The first stage optimization of the proposed model represents a regional integrated energy system planner whose purpose is to minimize its energy and environmental cost, while the second stage is an operation problem whose primary role is to achieve the optimal operation scheme of the system. The regional integrated energy system planner pursues best interests by co-optimizing the capacity configuration and power output of individual energy supply module, while the regional integrated energy system maximizes the installed capacity of renewable energy sources and minimizes the environmental costs. To illustrate the advantage of the proposed method, the NSGA-II algorithm and the mixed integer linear programming method are implemented to solve the model based on simulation. Besides, application of the optimization method proposed to the energy infrastructure of a regional integrated energy system in China is discussed, and the results obtained through simulation are compared to the bi-level optimization objectives. The results show that the proposed method is economical and effective in practical application.