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Driven by the rapid development of the Internet of Things, cloud computing and other emerging technologies, the connotation of cyberspace is constantly expanding and becoming the fifth dimension of human activities. However, security problems in cyberspace are becoming serious, and traditional defense measures (e.g., firewall, intrusion detection systems and security audit) often fall into a passive situation of being prone to attacks and difficult to take effect when responding to new types of network attacks with a higher and higher degree of coordination and intelligence. By constructing and implementing the diverse strategy of dynamic transformation, the configuration characteristics of systems are constantly changing, and the probability of vulnerability exposure is increasing. Therefore, the difficulty and cost of attack are increasing, which provides new ideas for reversing the asymmetric situation of defense and attack in cyberspace. Nonetheless, few related works systematically introduce dynamic defense mechanisms for cyber security. The related concepts and development strategies of dynamic defense are rarely analyzed and summarized. To bridge this gap, we conduct a comprehensive and concrete survey of recent research efforts on dynamic defense in cyber security. Specifically, we firstly introduce basic concepts and define dynamic defense in cyber security. Next, we review the architectures, enabling techniques and methods for moving target defense and mimic defense. This is followed by taxonomically summarizing the implementation and evaluation of dynamic defense. Finally, we discuss some open challenges and opportunities on dynamic defense in cyber security.

As the public cloud becomes one of the leading ways in data sharing nowadays, data confidentiality and user privacy are increasingly critical. Partially policy-hidden ciphertext policy attribute-based encryption (CP-ABE) can effectively protect data confidentiality while reducing privacy leakage by hiding part of the access structure. However, it cannot satisfy the need of data sharing in the public cloud with complex users and large amounts of data, both in terms of less expressive access structures and limited granularity of policy hiding. Moreover, the verification of access right to shared data and correctness of decryption are ignored or conducted by an untrusted third party, and the prime-order groups are seldom considered in the expressive policy-hidden schemes. This paper proposes a fully policy-hidden CP-ABE scheme constructed on LSSS access structure and prime-order groups for public cloud data sharing. To help users decrypt, HVE with a “convert step” is applied, which is more compatible with CP-ABE. Meanwhile, decentralized credible verification of access right to shared data and correctness of decryption based on blockchain are also provided. We prove the security of our scheme rigorously and compare the scheme with others comprehensively. The results show that our scheme performs better.

This paper proposes a new transmission policy for intelligent reflecting surface (IRS) empowered wireless powered internet of things systems. Particularly, an energy station (ES) wirelessly charges for multiple IoT devices during downlink wireless energy transfer (WET) and then these devices deliver their own message to an access point (AP) during uplink wireless information transfer (WIT). Also, an IRS is deployed to improve energy harvesting and data transmission capabilities. To enhance self-sustainability of the IRS, the IRS harvests energy from the ES based on the harvest-then-transmit protocol. In this paper, we maximize the sum throughput via optimizing the phase shifts of the IRS, the transfer time scheduling as well as the power splitting ratio. Due to the non-convexity of the formulated problem, we divide the problem into two sub-problems, each of which can be handled separately. Then, we adopt an alternating optimization (AO) algorithm with the semidefinite programming (SDP) relaxation. Also, we consider a special case where the circuit power consumption of IoT devices can be neglected. In this case, we derive a closed form solution for the optimal transmission time slots, power allocation and phase shift by the Lagrange dual method. Finally, numerical evaluations validate effectiveness of the proposed scheme, which significantly benefits from the IRS in improving network throughput.

Fabrication of heterostructure composed of one-dimensional (1D) and 2D semiconductors has inspired extensive interest in promoting photogenerated charge separation as well as performances of solar fuel production, but it is still challenging for (oxy)nitride photocatalysts due to their uncontrollable ammonia thermal preparative process. In this work, we report a synthesis on heterostructure of Ta3N5 nanorods and CaTaO2N (CTON) nanosheets (denoted as Ta3N5/CTON) by directly nitriding a 2D Dion-Jacobson (DJ) type of perovskite KCa2Ta3O10 (KCTO) precursor under the assistance of K2CO3 flux. It is demonstrated that the 2D morphology of KCTO can be well inherited to get 2D CTON, and the Ta-rich (non-stoichiometric ratio of Ca:Ta compared to CTON) feature of the KCTO as well as the easy evaporation of K species results in the formation of 1D Ta3N5 nanorods. Meanwhile, the formation of intermediate species K2Ca2Ta3O9N owning similar crystal lattice as Ta3N5 was detected and deduced to be responsible for the generation of Ta3N5 nanorods and observation of intimate interface between CTON and Ta3N5. Benefitting from the formation of special 1D/2D type-II heterostructure, obviously promoted charge separation as well as photocatalytic water splitting performance can be obtained. Extended discussion demonstrates the generality of the hard-template preparative strategy developed here. To our knowledge, this should be the first fabrication of 1D/2D heterostructure for the (oxy)nitride semiconductors, and the developed hard-template strategy may provide an alternative way of fabricating heterostructures of other semiconductors prepared at high temperature.

Medium voltage direct current (MVDC) shipboard power system (SPS) is the development trend of future ships. With the characteristics of compact structure and high-power density, the short circuit is much more serious than land-based power system, which seriously restricts the development of MVDC SPS. Therefore, there is an urgent need for prospective research on fault-protection. According to the fault characteristics of MVDC SPS, a DC superconducting current-limiting switch (SCLS) is proposed, so as to realize the current limiting protection of MVDC SPS. In this paper, a small-scale SCLS superconducting coil is wound, and a current limiting experiment of the prototype is completed. The results show that SCLS has a fast current-limiting response speed and a good current-limiting effect. The experiment summarizes the characteristics of the two current limiting modes of SCLS and it is concluded that R-type current limiting mode is more suitable for MVDC SPS.

Background A Chinese surgical robot, Micro Hand S, was introduced for clinical use as a novel robotic platform. This study aimed to comprehensively compare the early experience of the Micro Hand S robot-assisted total mesorectal excision (TME) with conventional approaches. Methods Between May 2017 and April 2018, 99 consecutive patients who underwent open, laparoscopic and Micro Hand S robot-assisted TME (O-/L-/RTME) for rectal cancer were included. Clinical and pathological outcomes were retrospectively analyzed. Surgical success as the primary endpoint was defined as the absence of (i) conversion, (ii) incomplete TME, (iii) involved circumferential and distal resection margins (CRM/DRM), (iv) severe complications. Results The rate of surgical success was similar (89.7 vs. 86.4 vs. 84.6%, p = 0.851) in the three groups and the respective incidences were as follows: conversion (not applicable, 4.5 vs. 2.3%, p = 1.000), incomplete TME (6.9 vs. 6.8 vs. 3.8%, p = 0.980), involved CRM/DRM (0 vs. 2.3 vs. 3.8%, p = 0.592), severe complications (3.4 vs. 4.5 vs. 7.7%, p = 0.844). Compared with open and laparoscopic surgery, the robotic surgery was associated with longer operative time, less blood loss, earlier first flatus time and liquid intake time, and shorter length of hospital stay (p Conclusions The Micro Hand S assisted TME is safe and feasible, showing comparable outcomes than conventional approaches, with superiority in blood loss, recovery of bowel function, length of hospital stay, but with increased operative time.

High-gain single-feed antennas are desired for current and future wireless systems. Slot-based highly overmoded cavity antennas are one solution, but the fact that they can only radiate broadside beams limits their applications. An innovative phase-control technique is developed for slot-based resonant cavity antennas that utilizes a planar array of closely-spaced, appropriately-sized metallic patches integrated into the very near field of their slot arrays. It facilitates the design and realization of the phase distribution over their radiating aperture that is required for them to generate single and/or multiple tilted beams pointed at specified directions. A TE(10)(11)(0)-mode slot-based cavity antenna is selected as the pathfinder system. A TE110-mode single-slot cavity antenna that is equivalent to the half-wavelength subsection of that cavity is introduced initially to monitor the phase radiated from each slot. The phase control surface is then carefully engineered to facilitate tilted output beams from the base design. The approach is validated with two subsequent tilted-beam systems. The first system achieves a single beam tilted to 30° with respect to the broadside direction. The second system is extended to produce two independently-directed titled beams pointing at –10° and 20°, respectively. All of the measured results agree well with their simulated values.

Free-of-charge metacomputing aims at integrating surplus computing resources and utilizing their inter-connected computing power to fulfil computational demands at virtually no cost. The existing efforts on free-of-charge metacomputing can be observed in grid computing, parasitic computing and volunteer computing. As extensively discussed in the literature, these three metacomputing forms all have their respective challenges and shortcomings, ranging from sophisticated enabling technologies to possible frequent interruptions, not to mention the potential ethical and legal issues in parasitic computing. Based on our observation on the growing marketing strategy of offering cloud service samples (free quotas), we argue that it is also possible to follow a metacomputing approach to take advantage of free resources in the public cloud market. By applying this idea to our educational work, we gradually developed an implementation framework to facilitate exploiting free quotas of cloud user accounts. The relatively unique features and characteristics of cloud resource exploitation eventually turn our effort into a distinctive metacomputing form, and we name it bonus computing. Guided by the implementation framework, we initially verified bonus computing’s effectiveness and efficiency by implementing a proof-of-concept (PoC) system over multiple cloud vendors. Then, we justified bonus computing’s applicability by extending the PoC system to a Monte Carlo solution to a real-world problem in Astronomy. Based on our existing practices and the recent SLURM cluster experiments, we have tried to comprehensively analyze bonus computing’s advantages and disadvantages against the other comparable metacomputing forms, which in turn strengthens our confidence in this work’s contribution especially to the educational community.

The hybridization between the outmost s orbitals of metal (Bi3+, Sn2+, Pb2+, Ag+) and O 2p orbitals has been widely employed to develop innovative semiconductors with upshift valence band as well as extended visible light response, but it is still challenging to obtain photocatalyst with absorption edge of above 550 nm. Here we report a novel Sn2+-based oxyfluoride Sn2TiNbO6F (STNOF) photocatalyst with a pyrochlore structure to exhibit an extended absorption edge to 650 nm and dual functionalities of both water reduction and oxidation. Density functional theory calculations suggest that the unprecedented broad-spectrum response of STNOF is mainly ascribed to the strengthened hybridization between O 2p and Sn 5s orbitals remarkably upshifting the valence band, which is caused by the distortion and compressive strain in the SnO6F2 dodecahedron with second-order Jahn-Teller effect due to partial fluorine substitution. The structural distortion and compressive strain are experimentally confirmed by the Fourier-transformed extended X-ray absorption fine spectra. As probe tests of the photocatalytic functionalities, water reduction and oxidation half reactions were examined to see obvious H2 and O2 evolution under visible light irradiation. This work may provide an alternative strategy of developing extended visible light responsive semiconductors for promising solar energy conversion.

Two novel types of dual-beam switching leaky-wave antenna (LWA) arrays based on substrate-integrated waveguides (SIWs) are proposed. The two antenna arrays consist of five SIW LWAs that work on the fundamental wave and -1st spatial harmonic wave simultaneously, so the arrays can realize fixed-frequency or frequency controlled dual-beam switching properties. The LWAs in one of the arrays have the same equivalent waveguide width and different slot periods, defined as the asymmetric dual-beam switching (ADBS) array. The LWAs in the other array have the same slot period and different equivalent waveguide widths, which is defined as the hybrid dual-beam switching (HDBS) array. The open stopbands of the arrays are suppressed by a simple structure. Using voltage-driven radio frequency chip switches (CSW-RFs) to change the excitation port, the arrays can realize the function of dual-beam switching at a fixed frequency. The measured results show that the forward beam of the ADBS array can switch from 13° to 80° while its backward beam switches from -75° to -10°, and the forward beam of the HDBS array is fixed at 45° while its backward beam switches from -10° to -80° when working at 28 GHz. Furthermore, the LWAs themselves can realize frequency-controlled ADBS in each excitation state. Therefore, the proposed arrays exhibit excellent performance in flexible dual-beam switching, which can be used in millimeter-wave applications where fixed-frequency beam switching or frequency-controlled beam switching is required.

Haploidentical allogeneic haematopoietic stem cell transplantation (haplo-HSCT) is a significant alternative treatment for severe aplastic anaemia (SAA). To improve this process by modifying the risk stratification system, we conducted a retrospective study using our database. 432 SAA patients who received haplo-HSCT between 2006 and 2020 were enrolled. These patients were divided into a training (n = 288) and a validation (n = 144) subset randomly. In the training cohort, longer time from diagnosis to transplantation, poorer Eastern Cooperative Oncology Group (ECOG) status and higher haematopoietic cell transplantation-specific comorbidity index (HCT-CI) score were independent risk factors for worse treatment-related mortality (TRM) in the final multivariable model. The haplo-HSCT scoring system was developed by these three parameters. Three-year TRM after haplo-HSCT were 6% [95% confidence interval (CI), 1-21%], 21% (95% CI, 7-40%), and 47% (95% CI, 20-70%) for the low-, intermediate-, and high-risk group, respectively (P < 0·0001). In the validation cohort, the haplo-HSCT scoring system also separated patients into three risk groups with increasing risk of TRM: intermediate-risk [hazard ratio (HR) 2·45, 95% CI, 0·92-6·53] and high-risk (HR 11·74, 95% CI, 3·07-44·89) compared with the low-risk group (P = 0·001). In conclusion, the haplo-HSCT scoring system could effectively predict TRM after transplantation.

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is widely used in the treatment of hematological diseases. It is well known that allogeneic grafts play a key role in predicting transplantation prognosis. Hematopoietic stem cells (HSCs) are a functional part of grafts and are capable of reconstructing hematopoiesis and immunity, but purified HSCs have not been identified or isolated to date. In clinical practice, allogeneic grafts have been optimized to improve transplantation outcomes. The optimized grafts are considered to engraft successfully, reconstruct immunity rapidly, and exert a graft-vs-leukemia (GVL) effect without causing severe graft-vs-host disease (GvHD). In the last several decades, considerable efforts have been made in searching for optimized grafts based on different graft manipulation approaches and different graft sources. Currently, there is no uniform standard for optimized grafts in allogeneic transplantation. In the future, sorting out the cellular elements responsible for the effects of allo-HSCT might be a research direction for further optimization of grafts. In this review, we propose the concept of optimized grafts and summarize the recent advances made in the process of optimizing grafts.

The security of power systems and electrical grids can be affected by the stochastic nature of wind energy. Therefore, reliable techniques for load forecasting and planning must be developed. This paper presents a model for short-term regional wind power forecasting based on small datasets. The model comprises three steps: input data correction, a hybrid neural network, and error analysis. First, regional numerical weather predictions (NWP) are corrected by using a stacked multilevel-denoising autoencoder (SMLDAE) to generate more effective inputs; this is the first study to use SMLDAE for NWP data correction. Second, a neural network-based hybrid model is employed for regional wind power forecasting to predict the wind power in the region. The proposed hybrid model employs three processes: multiscale mathematical morphological decomposition (MMMD), k-means clustering, and a stacked denoising autoencoder. MMMD can decompose the data directly in the time domain, thus, the signal does not need to be transferred from the time domain to the frequency domain to accomplish the decomposition. Third, a long short-term memory network is used for error analysis of the preliminary forecasted data. The preliminary results and error series are aggregated to generate the final forecasting result. For small datasets, we use multi-distribution mega-trend diffusion to augment the dataset. The proposed model was validated using a dataset consisting of data generated by regional wind farms in northern China. The results show that the proposed model enables wind forecasting at both the regional and single-farm level. Moreover, whereas most benchmark models require almost one year of data, the model requires only approximately three months of NWP data to produce reliable forecasting within the next 24 h.

Background Macro-reentrant atrial tachycardias (MATs) are a common complication after cardiac valve surgery. The MAT types and the effectiveness of MAT ablation might differ after different valve surgery. Data comparing the electrophysiological characteristics and the ablation results of MAT post-tricuspid or mitral valve surgery are limited. Methods Forty-eight patients (29 males, age 56.1 ± 13.3 years) with MAT after valve surgery were assigned to tricuspid valve (TV) group (n = 18) and mitral valve (MV) group (n = 30). MATs were mapped and ablated guided by a three-dimensional navigation system. The one-year clinical effectiveness was compared in two groups. Results Nineteen MATs were documented in TV group, including 16 cavo-tricuspid isthmus (CTI)-dependent AFL and 3 other MATs at right atrial (RA) free wall, RA septum and left atrial (LA) roof. Thirty-nine MATs were identified in MV group, including15 CTI-dependent AFL, 8 RA free wall scar-related, 2 RA septum scar-related, 8 peri-mitral flutter, 3 LA roof-dependent, 2 LA anterior scar-related, and 1 right pulmonary vein-related MAT. Compared with TV group, MV group had significantly lower prevalence of CTI-dependent AFL (38.5% vs. 84.2%), higher prevalence of left atrial MAT (35.9 vs.5.3%) and higher proportion of patients with left atrial MAT (40 vs. 5.6%), P = 0.02, 0.01 and 0.01, respectively. The acute success rate of MAT ablation (100 vs. 93.3%) and the one-year freedom from atrial tachy-arrhythmias (72.2 vs. 76.5%) was comparable in TV and MV group. No predictor for recurrence was identified. Conclusion Although the types of MATs differed significantly in patients with prior TV or MV surgery, the acute and mid-term effectiveness of MAT ablation was comparable in two groups. Trial registration: This study was registered as a part of EARLY-MYO-AF clinical trial at the website ClinicalTrials. gov (NCT04512222).

Background Oxidative damage has been found in various types of hair loss. As a polyphenolic phytoalexin, resveratrol (RSV) is known as an antioxidant, anti-inflammatory and anti-apoptotic agent. Objective Thus, we aim to examine the effects of RSV on hair growth. Methods In vivo C57BL/6 mice were used to evaluate the effects of RSV on hair cycle, hair length, skin thickness, hair follicle diameter, hair cycle score and the percentage of hair cycle stage. Then hair shaft length and hair cycle were evaluated by human hair follicles (HFs) ex vivo. The proliferative activities of human dermal papilla cells (hDPCs) cultured in vitro with RSV were assessed using RTCA. The ability of RSV to protect hDPCs against H2O2-induced oxidative damage is examined by a ROS assay kit. Results Topical application of RSV significantly promoted hair growth and stimulated the transition of hair cycle from telogen into the anagen phase on shaved C57BL/6 mice. Ex vivo experiments showed that RSV increased the hair shaft length of HFs and delayed the entry into catagen. In vitro experiments indicated that RSV proliferated hDPCs and prevented hDPCs from oxidative damage caused by H2O2. Conclusion RSV can promote hair growth and may be a potential candidate for the treatment of hair loss., Graphical Abstract

BACKGROUND At present, colorectal cancer is routinely treated with adjuvant radiotherapy and chemotherapy postoperatively. The adverse effects (AEs) of chemotherapy usually interrupt the treatment of chemotherapy. Traditional Chinese medicine (TCM) has demonstrated great potential in improving patients' clinical symptoms, regulating the immune function, improving the life quality, and reducing the AEs of chemotherapy. AIM To observe the clinical efficacy of Yiqi Jianpi anti-cancer prescription combined with chemotherapy in patients with colorectal cancer after operation. METHODS Data from patients diagnosed with colorectal cancer between January 2019 and February 2021 were collected from Liaoning Cancer Hospital and Institute and the Second Affiliated Hospital of Liaoning University of Traditional Chinese Medicine. Patients receiving the chemotherapy regimen of capecitabine plus oxaliplatin (CAPOX) after radical resection of colorectal cancer were prospectively collected and randomly divided into an experimental group and a control group. The experimental group was given Yiqi Jianpi anti-cancer prescription combined with the CAPOX regimen, while the control group was given the CAPOX regimen alone. After six cycles of chemotherapy, the scores of TCM symptoms, Karnofsky performance scale (KPS) score, levels of T-cell subsets, and AEs after chemotherapy of the two groups were compared. RESULTS A total of 70 patients were randomly divided into either an experimental group (n = 35, no dropout) or a control group (n = 33, with 2 dropouts). Compared with the control group, the experimental group improved significantly (P < 0.05) in scores of TCM symptoms, KPS score, levels of T-cell subsets, and AEs of chemotherapy. CONCLUSION Yiqi Jianpi anti-cancer prescription can effectively improve spleen deficiency, regulate the immune function, and alleviate the AEs of chemotherapy, so as to improve the life quality of patients with good therapeutic effects and application prospect in clinical practice.

An all-weather energy management scheme for island DC microgrid based on hydrogen energy storage is proposed. A dynamic model of a large-scale wind–solar hybrid hydrogen-generation power generation system was established, using a quasi-proportional resonance (QPR). We used the distributed Nautilus vertical axis wind power generation system as the main output of the system, and it used the photovoltaic and hydrogen energy storage systems as alternative energy sources. Based on meeting the load power requirements and controlling the bus voltage stability, we can convert the excess energy of the microgrid to hydrogen energy. With a shortage of load power, we can convert the stored hydrogen into electrical energy for the load. Based on the ANSYS FLUENT software platform, the feasibility and superiority over large-scale distributed Nautilus vertical axis wind power generation systems are verified. Through the MATLAB/Simulink software platform, the effectiveness of the energy management method is verified. The results show that the large-scale distributed Nautilus vertical axis wind power generation system runs well in the energy system, produces stable torque, produces energy better than other types of wind turbines, and has less impact on the power grid. The energy management method can ensure the normal operation of the system 24 h a day under the premise of maintaining the stable operation of the electric hydrogen system without providing external energy.

The medium voltage direct current (MVDC) is a promising direction of future shipboard power system (SPS). However, one of the main limitations encountered in its development is the fault isolation of DC side. This paper reveals the evolution process of short-circuit fault in typical MVDC SPS through equivalent circuit and transient simulation. Based on the analysis of protection needs, a superconducting current-limiting switch (SCLS) topology is proposed, which includes one superconducting coupled coil and two DC circuit breakers (DCCBs). The models of SCLS is built on MATLAB/Simulink and the current limiting principle and current sharing principle of SCLS are verified. The results show that the SCLS has effective current limiting performance and fault clearing effect.

Compared with the general multi-degree-of-freedom motor, the permanent magnet spherical motor has the advantages of simple structure, convenient control and small size. This paper analyzes the cogging torque of a surface-mounted spherical permanent magnet motor (SSPMM) with an 8-pole, 12-slot three-layer stator. The SSPMM has two kinds direction of cogging torque: rotation direction and deflection direction. In order to weaken the multi-directional cogging torque, a new auxiliary slot shape was proposed. Through theoretical analysis and finite element simulation, the FEA is compared with the analytical results to verify the accuracy of the method. It is verified that the research method can effectively reduce the cogging torque amplitude in two directions.

As medium voltage dc-based (MVDC) technology is widely considered in the shipboard integrated power system (IPS), the short fault protection of shipboard IPS is urgent. This paper suggests resistive type superconducting fault current limiter (R-SFCL), flux-coupling type SFCL (FC-SFCL), and a hybrid type SFCL (H-SFCL) alleviate fault current and improve the transient behaviors of shipboard MVDC IPS. All of these SFCLs are installed at the DC line. When pole to pole short fault occurs, resistive and inductive components play roles in current limiting. To evaluate these SFCLs and choose one for the system, theoretical analysis, simulation verification and experiments are done. According to the current limiting and economic cost index, H-SFCL is preferable in these SFCLs.

To disclose the possible dynamic behaviours of vehicle-track systems subject to an entire railway network, random vibration analysis is of great concern in railway engineering due to the system geo...

Purpose Appropriate prescription of oral anticoagulants (OACs) and good patient adherence are essential to ensure optimal anticoagulation in patients with atrial fibrillation (AF). The aim of this study is to develop a mobile health tool to aid both clinicians and patients with AF in anticoagulation therapy. Methods In this study, a novel anticoagulation management model integrating decision support and patient follow-up, the I-Anticoagulation, was developed based on a WeChat Mini Program. With this tool, the risks of stroke and bleeding in AF patients can automatically be calculated according to their characteristics. Anticoagulation regimens were recommended based on a trade-off analysis that balances stroke and bleeding risks according to recent clinical guidelines. A shared decision can be made with full communication between medical professionals and patients. Moreover, follow-up was also conducted using I-Anticoagulation. Results A total of 120 AF patients receiving anticoagulants (40 received warfarin and 80 received non-vitamin K antagonist oral anticoagulants [NOACs]) were included in the pilot study. The incidence of thromboembolic events was 2.5% and 1.3%, and the rates of bleeding events were 22.5% and 13.8% in the warfarin and NOAC groups, respectively. Generally, self-reported adherence was high, and the satisfaction with anticoagulation was good in all patients with AF. Conclusion Overall, the anticoagulation management model developed in this study could be involved in the full process of anticoagulation therapy in AF patients to improve rationality, adherence, and satisfaction in both medical professionals and patients. However, the usability, feasibility, and acceptability of the I-Anticoagulant-based anticoagulation management model need to be further assessed through well-designed random clinical trials.

PurposeA city is a spatial carrier of innovation activities. Improving the level of urban innovation can play a significant supporting role in building an innovative country. China began to implement the innovative city pilot policy in 2008 and continued to expand the policy into more areas for exploring the path of innovative urban development with Chinese characteristics and improving urban innovation.Design/methodology/approachBased on mechanism analysis, this paper used the panel data of 269 cities from 2003 to 2016 to empirically test the effect of the pilot policy on the level of urban innovation by using different methods, such as the difference-in-differences model.FindingsThe results show that the innovative city pilot policy significantly improves the level of urban innovation. However, according to the findings of the heterogeneity analysis, the effect of the pilot policy on improving the innovation level in direct-controlled municipalities, provincial capitals and sub-provincial cities is weaker than that in ordinary cities, and the effect of the pilot policy on improving the innovation level in cities with a higher quality of science and education resources is weaker than that in cities with lower quality of science and education resources.Originality/valueMoreover, as the level of urban innovation increases, the effect of the pilot policy on improving the level of urban innovation is an asymmetric inverted V shape, which means the effect is first strengthened and then weakened. The research also finds that the locational heterogeneity of the pilot policy for improving the level of urban innovation is not notable. In addition, the innovative city pilot policy can strengthen the government's strategic guidance, promote the concentration of talent, incentivize corporate investment and optimize the innovation environment, having a positive impact on urban innovation. Moreover, the effect of concentration of talent and the effect of corporate investment incentive are the important reasons for the pilot policy to promote the improvement of the level of urban innovation.

Objective. The aim of this study was to summarize and evaluate the efficacy of acupuncture in hypertension animal study. Methods. Studies were searched from six databases, including Medline, Embase, Chinese National Knowledge Infrastructure, Wanfang Data, VIP information database, and Chinese Biomedical Literature Database. Study quality of each included study was evaluated according to the Animal Research: Reporting of In Vivo Experiments (ARRIVE) guidelines, and the risk of bias was evaluated by the Systematic Review Centre for Laboratory Animal Experimentation (SYRCLE) tool. Systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) were selected as outcomes. Meta-analyses were performed using Stata 12.0 software. The effect size was calculated by combining SBP/DBP/MAP data with the random effects model, respectively. Results. 67 studies containing 1522 animals were included. According to the ARRIVE guideline, 8 items were assessed as poor and 4 items were assessed as excellent. According to the SYRCLE tool, all studies were judged as having high risk of bias. Compared with the hypertension group, the pooled results showed significant antihypertension effects of acupuncture for SBP, DBP, and MAP. Similarly, compared with the sham-acupuncture group, the pooled results showed significant antihypertension effects of acupuncture for SBP, DBP, and MAP. Conclusion. Although pooled data suggested that the acupuncture group was superior to the hypertension group or sham-acupuncture group for SBP/DBP/MAP, the presentation of poor methodological quality, high risk of bias, and heterogeneity deserves cautious interpretation of the results.

Gastric cancer (GC) ranks the third among global cancer-related mortality, especially in East Asia. Angiogenesis plays an important role in promoting tumor progression, and clinical trials have demonstrated that anti-angiogenesis therapy is effective in GC management. Natriuretic peptide receptor A (NPRA) functions significantly in promoting GC development and progression. Whether NPRA can promote angiogenesis of GC remains unclear. Tumor samples collection and immunohistochemical experiment showed that the expression of NPRA was positively correlated with the expression of CD31 and vessel density. In vivo and in vitro analysis showed that NPRA could promote GC-associated angiogenesis and tumor metastasis. Results of Co-IP/MS showed that NPRA could prevent HIF-1α from being degraded by binding to HIF-1α. Protection of HIF-1α improved VEGF levels and thus promoted angiogenesis. In summary, NPRA protected HIF-1α from proteolysis by binding to HIF-1α, increased the expression of HIF-1α, and promoted GC angiogenesis. This study has discovered a new mechanism for NPRA to promote gastric cancer development and a new regulatory mechanism for HIF-1α.

Small-signal models (SSM) of modular multilevel converter (MMC) based HVDC grid under unbalanced grid conditions in recent literatures do not consider interactions between MMC and dc network. Therefore, it is necessary to correctly model the double-fundamental-frequency zero-sequence circulating currents (DFF-ZSCC) existing under unbalanced grid conditions, although they can be suppressed to avoid penetrating into dc side. In view of that, a general and modular small-signal modeling method of MMC-HVDC grid under unbalanced grid condition is developed. Firstly, a general d-q transformation process for multi-sequence and multi-frequency components is introduced to build the state-space model of MMC electric part in d-q frame. Secondly, the SSM of dc network, which is divided into dc- and double-fundamental-frequency parts, is developed based on the existing frequency-dependent-cascaded-pi (FDC-PI) cable model. Then, to interface MMC stations with dc network under unbalanced grid conditions, a general method to synchronize the variables of double fundamental frequency at dc side of each MMC station is introduced to compose the SSM of the entire HVDC grid from SSMs of each MMC and dc network. Finally, taking a three-terminal MMC-HVDC grid as an example, two SSMs of the MMC-HVDC grid with FDC-PI cable model and single-PI cable model are developed in Matlab, respectively. The small-signal dynamics and stability of both SSMs of the grid under unbalanced grid conditions are compared to validate the accuracy and stability of the proposed SSM of the whole HVDC grid. The simulation results validate the correctness and effectiveness of the proposed modular modeling method.

With the maturity of horizontal drilling and hydraulic fracturing technologies, countries rich in shale gas have begun to promote the development of the shale gas industry. The impact of the booming shale gas industry on the regional economy has also become a main focus. Shale gas’ exploration and extraction may have positive spillover effects on other sectors, resulting in population growth and job creation. However, negative spillover effects can occur through rising local goods prices and its adverse effects on the local quality of life, which in turn could harm population growth and employment. By using the synthetic control method, we investigates the shale gas fields in Chongqing to reveal the relationship between population growth, employment and shale gas development in Fuling, Nanchuan and Wulong districts. Our results indicate that due to the development of the shale gas industry, the number of urban non-private sector employees in three districts and counties has decreased. From 2017 to 2018, this decline had gradually weakened and the population growth had been negatively affected.

Proton-conducting solid oxide fuel cells (P–SOFCs) are promising energy conversion devices that convert chemical energy directly to electrical energy. P–SOFCs have attracted significant attention in the past few years because of their superiority over the oxygen-ion-conducting solid oxide fuel cells (O–SOFCs) in terms of better feasibility of efficient operation at lower temperatures, non-dilution of fuel at the anode, and higher theoretical efficiency. This review focuses on the scientometric analysis of 1008 quality articles retrieved from the Scopus database. The historical trends and progress in P–SOFCs are presented starting from the inception of the demonstration of the concept of proton conductivity in solid oxide fuel cells from 1986 to 2021. Furthermore, the notable achievements in the material development of various components of P–SOFC are expounded. The scientometric analysis reveals that only 28% of the countries in the world are involved in P–SOFC research and the National Natural Science Foundation of China is the top featured funding sponsor for many research studies related to P–SOFC development. This article can serve as an easy guide for P–SOFC research enthusiasts to navigate through the overview of this research area and identify potential collaborators, funding sponsors, most impactful researchers, countries, and articles.

This paper investigated project-based governance (PBG) in China’s higher vocational education (HVE) with a main research question asking how PBG works in China’s HVE. Using case study as a research strategy, the paper examines the application and effect of the PBG model on Chinese HVE within the analytical framework of PBG-based agency theory. Twenty-three faculty members from both administrative and academic departments in College Plateau (pseudonym) were recruited to participate in a person-to-person interviews. They were expected to share their observations and perspectives on the PBG model as applied to HVE. As supplementary materials, the Chinese government’s policy documents and statistics, as well as institutional policy documents, were also looked at for a brief discussion of governance of China’s HVE. The results showed that the PBG model has greatly challenged the traditional administrative, distribution and personnel systems, as well as the college-enterprise cooperation model, and academic performance of higher vocational colleges (HVCs). These changes have brought higher academic achievements and greater social resources to College Plateau. However, they have also caused many negative effects, such as homogeneity of organizations and the Matthew effect among HVCs.

Spinal cord injury (SCI) is one common neurological condition which involves primary injury and secondary injury. Neuron inflammation and apoptosis after SCI is the most important pathological process of this disease. Here, we tried to explore the influence and mechanism of miRNAs on the neuron inflammatory response and apoptosis after SCI. First, by re-analysis of Gene Expression Omnibus dataset (accession GSE19890), miR-182 was selected for further study because of its suppressive effects on the inflammatory response in the various types of injuries. Functional experiments demonstrated that miR-182 overexpression promoted functional recovery, reduced histopathological changes, and alleviated spinal cord edema in mice. It was also observed that miR-182 overexpression reduced apoptosis and attenuated the inflammatory response in spinal cord tissue, as evidenced by the reduction of tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-1β, and the induction of IL-10. Using a lipopolysaccharide (LPS)-induced SCI model in BV-2 cells, we found that miR-182 was downregulated in the BV-2 cells following LPS stimulation, and upregulation of miR-182 improved LPS-induced cell damage, as reflected by the inhibition of apoptosis and the inflammatory response. IκB kinase β (IKKβ), an upstream target of the NF-κB pathway, was directly targeted by miR-182 and miR-182 suppressed its translation. Further experiments revealed that overexpression of IKKβ reversed the anti-apoptosis and anti-inflammatory effects of miR-182 in LPS stimulated BV-2 cells. Finally, we found that miR-182 overexpression blocked the activation of the NF-κB signaling pathway in vitro and in vivo, as demonstrated by the downregulation of phosphorylated (p‑) IκB-α and nuclear p-p65. Taken together, these data indicate that miR-182 improved SCI-induced secondary injury through inhibiting apoptosis and the inflammatory response by blocking the IKKβ/NF-κB pathway. Our findings suggest that upregulation of miR-182 may be a novel therapeutic target for SCI., overexpression of the microRNA miR-182 promotes functional recovery and reduced histopathological changes in spinal cord injury mice. miR-182 overexpression reduces apoptosis and attenuates the inflammatory response in spinal cord tissues by blocking the IKKβ/NF-κB pathway. These findings suggest that upregulation of miR-182 may be a novel therapeutic target for SCI.

In this paper, we propose a progressive model predictive control scheme (PMPCS) by considering the cooperative control of local planning and path tracking for intelligent vehicles. An improved particle swarm optimization (IPSO) based model predictive control (MPC) method is developed to solve the planning and tracking problem. With the PMPCS, the total computational burden can be reduced sharply because of the seamless connection and mutual promotion between the optimization of two layers. Besides we also propose a novel planning algorithm, which can take traffic lights and overtaking time constraint into account. To solve these problems, we first combine model predictive control with artificial potential field (APF) to get a collision-free path by treating the time-varying safety constraints as the scope of the repulsive force and an asymmetrical lane potential field function. Furthermore, the pseudo velocity planning method is adopted to take traffic lights into account in the planning module. Simulation results show the reliability of the proposed algorithm and the advantages of the scheme compared with general hierarchical algorithm.

Objective The present study aimed to verify the feasibility and preliminary effects of nurse-led square dancing designed to improve older adults’ cognitive function and depressive symptoms who with MCI. Methods A quasi-experimental pilot study design was adopted for the present study. Screening for cognitive function was conducted among older adults (≥ 60 years old) living in two communities in Beijing who complained of memory loss. A total of 107 older patients with MCI and depressive symptoms were diagnosed after obtaining informed consent. Thirty-five patients selected from each community were included in the study as control and intervention groups, respectively. The two groups of patients received health education while the intervention group participated in a square dance intervention program led by nurses three times per week for 60 min per session over a period of three months. The Montreal Cognitive Assessment-Peking version (MoCA-P) and Geriatric Depression Scale (GDS-30) were used to assess the cognitive function and depressive symptoms of patients in the two groups at three time intervals; before intervention, at the end of the three-month intervention period, and over a three-month follow-up period after the end of intervention. Results Feasibility of the intervention was established with a high completion rate of 90%. Data collection for 63 out of 70 patients enrolled for the study was completed after six months. MoCA-P and GDS-30 scores of the intervention group were significantly different after the intervention when compared with the control group. A significant improvement in cognition was observed in the intervention group, and depressive symptoms decreased after intervention and follow-up when compared with the control group. During the intervention and follow-up phases, the MoCA-P score of the intervention group increased gradually with time. Furthermore, the MoCA-P and GDS-30 scores of the control group remained unchanged. Conclusion This study has revealed that square dance intervention exerts a positive impact on cognitive function and depressive symptoms among older patients suffering from MCI and depressive symptoms. The results of this study support the feasibility and preliminary effects of square dancing on relieving cognitive decline and depressive symptoms. Square dancing is a recommended type of intervention that can be applied to the local Chinese population because of its simplicity, convenience, and suitability for the older adults.

Ring-stiffened flat bottom tanks are widely used in many industries for the storage of liquids, such as oil, fertilizers, water, sewage and sludge. Material efficiency is achieved by combining thin plates with ring-stiffeners. When the bin is covered by a dome or cone roof, high meridional forces due to live or snow loads may trigger axial buckling of the shell. Ring stiffeners are beneficial, not just against buckling due to wind, but to reduce the risk of stability failure of tanks and silos caused by meridional compression as well. This paper presents the outcome of a parametrical study concerned with axial buckling and the most effective placement of the stiffening rings depending on the stiffener distance, cross-sectional area and slenderness of the cylinder. Buckling curve parameters are deduced using the modified capacity curve. These allow the direct application of the analysis results in a hand calculation procedure that enables practitioners to take into account the benefits, which come with ring stiffeners against buckling due to axial compression., ce/papers, 4 (2-4), ISSN:2509-7075, EUROSTEEL 2021: Sheffield - Steel's Coming Home

Traditional flat wireless power transmission is charging in a “one-to-one” manner. When the rotation angle of the receiving and transmitting coils is offset, their mutual inductance M and coupling ...

Studies have focused on elucidating the sharing behavior of media users. However, few studies have specifically investigated users' health information sharing behavior in the social media context, especially WeChat. This study proposes a theoretical research model that integrates social capital and user gratification with the theory of planned behavior to explore health information sharing behavior of WeChat users. Based on online survey data collected from 616 WeChat users, correlation analysis and structural equation modeling were sequentially performed. It was found that both social capital and gratification factors play important roles in influencing WeChat users' health information sharing. Social interaction, acting both as social capital and gratification factor directly and indirectly generated positive effects on health information sharing intention. In conclusion, this study revealed the key determinants of health information sharing intention among WeChat users and examined the mediation effects to effectively understand users' health information sharing behavior.

S700K turnout is the key equipment of railway line conversion. The diagnosis of S700K turnout in a normal, sub-health, and fault running state is the primary premise to ensure the safe operation of the railway. Aiming at the consistency between the characteristics of the power curve of S700K turnout and its state information, this paper proposes a new algorithm based on variational mode decomposition (VMD) and kernel principal component analysis (KPCA) to extract the characteristics of the power curve of S700K turnout. It uses fuzzy clustering analysis to diagnose the running state of S700K turnout. First, to extract the detailed components of the action power curve, it is decomposed into intrinsic mode function with limited bandwidth (BIMF) by VMD. Secondly, the multi-scale permutation entropy (MPE) is used to characterize the signal complexity of the power curve and different BIMF components, which are taken as the running state feature set. After KPCA analysis, eigenvalues with a contribution rate greater than 95% are selected as the state eigenvector. The experimental results show that the diagnosis algorithm can effectively identify the running state of S700K turnout, meet the characteristics of fewer fault samples of S700K turnout, and do not need to train in advance, which is of great significance for field guidance.

Objective: The resonance frequency (Fr) of twelve meridians was observed by means of sweep frequency of weak constant current, and a method of evaluating Fr was explored. Method: Four-electrode bioimpedance spectroscopy was used in the study. Constant current of 1~100Hz was applied from a phase-locked amplifier through the excitation electrode to the twelve meridians of 30 healthy subjects. Data were collected by the test electrode and the Fr of the twelve meridians was obtained by data fitting in Matlab. Result: Among the twelve meridians, the Fr of the small intestine meridian is the lowest, and the gallbladder meridian is the highest, which are 23.18±0.99Hz and 28.27±1.39 Hz, respectively. The mean resonance frequencies of meridians of the same name on hand and foot are 24.80±1.34Hz and 26.22±1.17Hz, respectively. The Fr of the Shao Yin meridian of the hands and feet is basically equal, the other five pairs of foot meridians are all higher than the hand meridian, and the difference of the Yang meridian of the same name is greater than the Yin meridian of the same name, the Fr of hand Shao Yang meridian, hand Tai Yang meridian and hand Yang Ming meridian were lower than those of foot meridians. The mean value of 6 pairs of yin and yang meridians are 25.59 ± 1.97Hz and 25.42 ± 0.70Hz, respectively. Conclusion: The resonance frequencies of the twelve meridians ranged from 23 to 28Hz approximately.

Direct phase modulation is one of the most urgent and difficult issues in the terahertz research area. Here, we propose a new method employing a two-dimensional electron gas (2DEG) perturbation microstructure unit coupled to a transmission line to realize high-precision digital terahertz phase manipulation. We induce local perturbation resonances to manipulate the phase of guided terahertz waves. By controlling the electronic transport characteristics of the 2DEG using an external voltage, the strength of the perturbation can be manipulated, which affects the phase of the guided waves. This external control permits electronic manipulation of the phase of terahertz waves with high precision, as high as 2−5° in the frequency range 0.26–0.27 THz, with an average phase error of only 0.36°, corresponding to a timing error of only 4 fs. Critically, the average insertion loss is as low as 6.14 dB at 0.265 THz, with a low amplitude fluctuation of 0.5 dB, so the device offers near-ideal phase-only modulation. A terahertz phase modulator based on the switchable perturbation resonance in two-dimensional electron gas is demonstrated. Phase manipulation with precision ranging from 2° to 5° is obtained at frequencies in the range from 0.26 to 0.27 THz.

This paper describes the construction and application of the first English-Chinese Parallel Corpus of Hydrogen Energy (PCOHE) in China, including design framework, collecting and processing of corpus materials, and its applications.Thepaper adopts statistical analysis with the help of corpussoftware to portray the linguistic characteristics of the hydrogen energy texts and study the translation strategy of the translated texts, which is expected to improve the efficiency and accuracy of translation. Although PCOHE is intended for translation studies of hydrogen energy texts, it can also be applied to such areas as the learning of hydrogen energy and machine translation.

Background Few mortality-scoring models are available for solid tumor patients who are predisposed to develop Escherichia coli–caused bloodstream infection (ECBSI). We aimed to develop a mortality-scoring model by using information from blood culture time to positivity (TTP) and other clinical variables. Methods A cohort of solid tumor patients who were admitted to hospital with ECBSI and received empirical antimicrobial therapy was enrolled. Survivors and non-survivors were compared to identify the risk factors of in-hospital mortality. Univariable and multivariable regression analyses were adopted to identify the mortality-associated predictors. Risk scores were assigned by weighting the regression coefficients with corresponding natural logarithm of the odds ratio for each predictor. Results Solid tumor patients with ECBSI were distributed in the development and validation groups, respectively. Six mortality-associated predictors were identified and included in the scoring model: acute respiratory distress (ARDS), TTP ≤ 8 h, inappropriate antibiotic therapy, blood transfusion, fever ≥ 39 °C, and metastasis. Prognostic scores were categorized into three groups that predicted mortality: low risk ( 20% mortality, ≥ 3 points). The TTP-incorporated scoring model showed excellent discrimination and calibration for both groups, with AUC being 0.833 vs 0.844, respectively, and no significant difference in the Hosmer–Lemeshow test (6.709, P = 0.48) and the chi-square test (6.993, P = 0.46). Youden index showed the best cutoff value of ≥ 3 with 76.11% sensitivity and 79.29% specificity. TTP-incorporated scoring model had higher AUC than no TTP-incorporated model (0.837 vs 0.817, P Conclusions Our TTP-incorporated scoring model was associated with improving capability in predicting ECBSI-related mortality. It can be a practical tool for clinicians to identify and manage bacteremic solid tumor patients with high risk of mortality.

A novel baseline-free damage identification method based on high frequency operational deflection shapes (ODSs) is presented for debonding detection in lattice sandwich structures (LSSs). Two numer...

Solvent-based post-combustion capture technologies have great potential for CO2 mitigation in traditional coal-fired power plants. Modelling and simulation provide a low-cost opportunity to evaluate performances and guide flexible operation. Composed by a series of partial differential equations, first-principle post-combustion capture models are computationally expensive, which limits their use in real time process simulation and control. In this study, we propose a first-principle approach to develop the basic structure of a reduced-order model and then the dominant factor is used to fit properties and simplify the chemical and physical process, based on which a universal and hybrid post-combustion capture model is established. Model output at steady state and trend at dynamic state are validated using experimental data obtained from the literature. Then, impacts of liquid-to-gas ratio, reboiler power, desorber pressure, tower height and their combination on the absorption and desorption effects are analyzed. Results indicate that tower height should be designed in conjunction with the flue gas flow, and the gas-liquid ratio can be optimized to reduce the reboiler power under a certain capture target.

The smart city makes use of information technology to integrate city systems and functions to optimize city management and services. In this paper, we treat the smart city as a Cyber-Physical-Social System (CPSS), which is a kind of heterogeneous complex network system. Since information diffusion is fundamental to complex network analysis, we would like to summarize information diffusion in CPSS, including features of information diffusion, its application in the field of smart city, and critical technologies of information diffusion modeling and analysis. Finally, we point out open research issues, challenges, and put forward the possible future direction for research of information diffusion in smart city CPSS.

OBJECTIVES Transcranial direct current stimulation (tDCS) facilitates or inhibits spontaneous neuronal activity by low-intensity current. In this study, we evaluated the effects of tDCS and sham stimulation combined with speech language therapy (SLT) on nonfluent poststroke aphasia (PSA) patients. MATERIALS AND METHODS Patients with PSA were randomly divided into the anode tDCS (A-tDCS) group (n = 8) and sham tDCS (S-tDCS) group (n = 10). The anodes and cathodes were fixed over left inferior gyrus frontalis (L-IFG) and the deltoid muscle of the right shoulder. A-tDCS consisted of 2 mA for 20 min, while S-tDCS current started at 2 mA but automatically decreased to 0 mA after 30 sec. Stimulation was concurrent with 30 min of SLT. Stimulation + SLT sessions occurred five times a week for four weeks. The Western Aphasia Battery (WAB) was given before treatment to obtain the baseline score and once more after all sessions were completed, and the Aphasia Quotient (AQ) was calculated. RESULTS After tDCS treatment, the AQ mean(SD) in both groups was significantly higher than before treatment (p

Prospective study. The main purpose of this study was to investigate whether the use of a tourniquet changes the blood coagulation state following primary total knee arthroplasty (TKA) by means of conventional coagulation tests and thromboelastography (TEG) analyses. A total of 154 patients who underwent primary unilateral TKA from January 2018 to October 2020 were enrolled. Seventy-nine patients were randomized into a tourniquet group, and 75 were randomized into a no-tourniquet group. Demographic data, surgical time, intra-operative blood loss, transfusion rate, and wound complications were collected. Complete blood count, conventional coagulation tests, and TEG were performed the day before surgery, one day after surgery, three days after surgery, and seven days after surgery. Lower extremity Doppler ultrasound was performed the day before surgery and seven days after surgery. The baseline characteristics of the patients were similar between the two groups. Hidden blood loss, transfusion rate, and wound complications were similar between the two groups, but the intra-operative blood loss of the tourniquet group was lower than that of the no-tourniquet group. The calculated total blood loss of the tourniquet group was higher than that of the no-tourniquet group. In terms of conventional coagulation tests and TEG, the tourniquet group had higher values of fibrin degradation products, D-dimer, maximum amplitude, and coagulation index (p