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Effects of brine corrosion and Alkali-Silicate Reaction (ASR) on High Performance Concrete (HPC) incorporating ASR inhibition measures were investigated. The study involved developing HPC with ASR inhibition measures and exposing it to brine corrosion for a period of 10 years to investigate the compressive strength and mesoscopic mechanical properties within the Interfacial Transition Zone (ITZ) of coarse and fine aggregate in HPC. The results reveal that the microhardness of the ITZ surrounding alkali-active fine aggregate is the lowest due to the synergistic influence of ASR and brine corrosion. Additionally, the correlation between macroscopic and mesoscopic mechanical properties was established and macroscopic parameters for mortar and ITZ were derived. These parameters were subsequently used in the numerical computation of a three-dimensional mesoscopic mechanical model depicting the compressive strength of HPC cubes. The numerical simulation of the concrete mesoscopic mechanical model revealed that HPC with ASR inhibition measures, after prolonged exposure to salt lake brine corrosion, manifests mesoscopic mechanical characteristics in compressive failure within cube specimens. The propagation of cracks directly through the coarse aggregate results in a distinctive splitting failure pattern for the HPC specimens.

The harsh geological conditions in the northwest region of China, characterized by widespread saline-alkali soil rich in alkali ions, pose a high risk of Alkali-Silica reaction (ASR) in concrete, particularly due to the presence of ASR-active natural river sands. To address ASR hazards, locally applied concrete often employs High-Performance concrete (HPC) prepared with high proportions of mineral admixtures. In this paper, the alkali content is controlled by adding mixed water with NaOH to the initial configuration of concrete, and three different alkali content states are set up. A 1 mol/L NaOH solution was used to simulate alkaline conditions, and HPC specimens were immersed for an extended period to investigate the effects of equivalent alkali content, immersion time, concrete strength, and admixture on the flexural mechanical properties of HPC under the condition of long-term alkali immersion. Results indicate that, the strength grade was positively correlated with the flexural strength of HPC, but the alkali content was negatively. Initial immersion significantly enhances strength, followed by a gradual decline after long-term immersion. Among three types of admixture addition methods, the impact on flexural strength of HPC immersed in alkaline solution for 10 years follows the order: Double doped air entraining agent and rust inhibitor is greater than single doped air entraining agent is greater than single doped rust inhibitor. In the process of macroscopic test, it is difficult to observe the variation rule of stress and strain in detail, only the final aggregate failure mode can be analyzed. In order to analyze the strain change of the specimen and the failure process of the aggregates more accurately, a three-dimensional random aggregate concrete mesoscopic model was established, and equations relating microhardness to the mechanical properties of concrete components were derived from statistical analysis, providing a basis for parameter selection in the model. Results demonstrate that with increasing strength, the occurrence time of initial cracks is delayed, and the ratio of cracks bypassing aggregates (cracks develop along the ITZ between aggregate and mortar until complete failure) decreases, and the ratio of cracks penetrating aggregates (cracks develop directly through aggregates in an almost vertical direction) increases.

Bipolar blocking and commutation failure in the renewable energy transmission system through ultra-high voltage direct current will produce significant temporary overvoltage. This paper analyzes the physical process of sending end grid overvoltage caused by two types of DC faults and establishes a DC overvoltage model considering renewable energy sources. According to characteristics of the sending end grid, the influence of the system equivalent impedance, the proportion of renewable energy output, the active and reactive power coefficients of the renewable energy sources during the low voltage ride through process on the overvoltage is analyzed respectively, and the relationship between the proportion of renewable energy output and the short-circuit ratio under the overvoltage constraint is constructed. The validity and practicality of the model and analysis method proposed in this paper are verified by combining the typical transmission system at the sending end of the actual power grid and regional power grid systems.

With the wide application of power electronized resources (PERs), the amplitude and frequency of voltages show significant time-varying characteristics under asymmetrical faults. As a result, the traditional phasor model, impedance model, and symmetrical components method based on the constant amplitude and frequency of voltages are facing great challenges. Hence, a novel asymmetrical fault analysis method based on conjugate vectors is proposed in this paper which can meet the modeling and analysis requirements of the network excited by voltages with time-varying amplitude/frequency. Furthermore, asymmetrical fault characteristics are extracted. As an application, a faulted phase identification (FPI) strategy is proposed based on the fault characteristics. The correctness and superiority of the asymmetrical fault analysis method and FPI strategy are verified in time-domain simulations and a real-time digital simulator.

With integration of large-scale renewable energy, new controllable devices, and required reinforcement of power grids, modern power systems have typical characteristics such as uncertainty, vulnerability and openness, which makes operation and control of power grids face severe security challenges. Application of artificial intelligence (AI) technologies represented by machine learning in power grid regulation is limited by reliability, interpretability and generalization ability of complex modeling. Mode of hybrid-augmented intelligence (HAI) based on human-machine collaboration (HMC) is a pivotal direction for future development of AI technology in this field. Based on characteristics of applications in power grid regulation, this paper discusses system architecture and key technologies of human-machine hybrid-augmented intelligence (HHI) system for large-scale power grid dispatching and control (PGDC). First, theory and application scenarios of HHI are introduced and analyzed; then physical and functional architectures of HHI system and human-machine collaborative regulation process are proposed. Key technologies are discussed to achieve a thorough integration of human/machine intelligence. Finally, state-of-the-art and future development of HHI in power grid regulation are summarized, aiming to efficiently improve the intelligent level of power grid regulation in a human-machine interactive and collaborative way.

Summary: Background: Diabetic kidney disease (DKD) is a leading cause of end-stage kidney disease and is associated with high mortality rates. The influence of routine clinical parameters on DKD onset in patients with type 2 diabetes mellitus (T2DM) remains uncertain. Methods: In this systematic review and meta-analysis, we searched multiple databases, including PubMed, Embase, Scopus, Web of Science, and Cochrane Library, for studies published from each database inception until January 11, 2024. We included cohort studies examining the association between DKD onset and various clinical parameters, including body mass index (BMI), hemoglobin A1c (HbA1c), systolic blood pressure (SBP), diastolic blood pressure (DBP), total cholesterol (TC), triglycerides (TG), low-density lipoprotein (LDL), high-density lipoprotein (HDL), and serum uric acid (UA). Random-effect dose–response meta-analyses utilizing one-stage and/or cubic spline models, were used to estimate correlation strength. This study is registered in PROSPERO (CRD42022326148). Findings: This analysis of 46 studies involving 317,502 patients found that in patients with T2DM, the risk of DKD onset increased by 3% per 1 kg/m2 increase in BMI (relative risk (RR) = 1.03, confidence interval (CI) [1.01–1.04], I2 = 70.07%; GRADE, moderate); a 12% increased risk of DKD onset for every 1% increase in HbA1c (RR = 1.12, CI [1.07–1.17], I2 = 94.94%; GRADE, moderate); a 6% increased risk of DKD onset for every 5 mmHg increase in SBP (RR = 1.06. CI [1.03–1.09], I2 = 85.41%; GRADE, moderate); a 2% increased risk of DKD onset per 10 mg/dL increase in TG (RR = 1.02, CI [1.01–1.03], I2 = 78.45%; GRADE, low); an 6% decreased risk of DKD onset per 10 mg/dL increase in HDL (RR = 0.94, CI [0.92–0.96], I2 = 0.33%; GRADE, high), and a 11% increased risk for each 1 mg/dL increase in UA (RR = 1.11, CI [1.05–1.17], I2 = 79.46%; GRADE, moderate). Subgroup analysis revealed a likely higher risk association of clinical parameters (BMI, HbA1c, LDL, and UA) in patients with T2DM for less than 10 years. Interpretation: BMI, HbA1c, SBP, TG, HDL and UA are potential predictors of DKD onset in patients with T2DM. Given high heterogeneity between included studies, our findings should be interpreted with caution, but they suggest monitoring of these clinical parameters to identify individuals who may be at risk of developing DKD. Funding: Shenzhen Science and Innovation Fund, the Hong Kong Research Grants Council, and the HKU Seed Funds, and Scientific and technological innovation project of China Academy of Chinese Medical Sciences.

Abstract Background Huazhuo Tiaozhi granule (HTG) is a herbal medicine formula widely used in clinical practice for hypolipidaemic effects. However, the molecular mechanisms underlying dyslipidaemia treatment have not been well elucidated. Results A significant reduction in the levels of total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) was observed in the serum of patients with dyslipidaemia after HTG treatment, without disruption in the levels of aspartate transaminase (AST), alanine transaminase (ALT), urea nitrogen (BUN), and creatinine (Cr). The dyslipidaemia rat model was induced by a high-fat diet and treated with Xuezhikang (0.14 g/kg/d) or HTG (9.33 g crude herb/kg/day) by gavage for 8 weeks. Body weight and liver index were markedly decreased in dyslipidaemic rats after treatment with Xuezhikang or HTG. HTG administration markedly ameliorated hyperlipidaemia by decreasing the levels of TC and LDL-C in serum and hepatic lipid accumulation. In vitro, lipid accumulation in LO2 and HepG2 cells was alleviated by serum treatment with HTG. High lactylation was observed in 198 proteins, including lactylation of histone H2B (K6), H4 (K80). Deep sequencing of microRNAs showed that miR-155-5p was significantly downregulated. Conclusions This study demonstrates that HTG is an effective and safe formula for treating dyslipidaemia, which promotes lactylation in hepatocytes, and the retardation of miR-155-5p biogenesis. Graphical abstract

Abstract Background To develop and validate radiomics models for prediction of tumor response to neoadjuvant therapy (NAT) in patients with locally advanced rectal cancer (LARC) using both pre-NAT and post-NAT multiparameter magnetic resonance imaging (mpMRI). Methods In this multicenter study, a total of 563 patients were included from two independent centers. 453 patients from center 1 were split into training and testing cohorts, the remaining 110 from center 2 served as an external validation cohort. Pre-NAT and post-NAT mpMRI was collected for feature extraction. The radiomics models were constructed using machine learning from a training cohort. The accuracy of the models was verified in a testing cohort and an independent external validation cohort. Model performance was evaluated using area under the curve (AUC), sensitivity, specificity, positive predictive value, and negative predictive value. Results The model constructed with pre-NAT mpMRI had favorable accuracy for prediction of non-response to NAT in the training cohort (AUC = 0.84), testing cohort (AUC = 0.81), and external validation cohort (AUC = 0.79). The model constructed with both pre-NAT and post-NAT mpMRI had powerful diagnostic value for pathologic complete response in the training cohort (AUC = 0.86), testing cohort (AUC = 0.87), and external validation cohort (AUC = 0.87). Conclusions Models constructed with multiphase and multiparameter MRI were able to predict tumor response to NAT with high accuracy and robustness, which may assist in individualized management of LARC.

The natural environment in the high-altitude regions of Northwest China is extremely harsh, characterized by numerous salt lakes. The high concentrations of chloride salts, sulfates, and alkali metal ions in these areas can induce alkali–silica reactions (ASRs) in concrete. These reactions generate harmful gel within the concrete, causing expansion and cracking, which significantly impacts the durability of concrete structures. This study investigates the evolution of the mechanical properties in high-performance concrete (HPC) under long-term ASR by incorporating different admixtures and varying the equivalent alkali content. A three-dimensional random aggregate mesoscopic model was used to simulate static compression tests under various operational conditions. Non-destructive testing methods were utilized to determine the expansion rate, internal, and surface damage variables of the concrete. The experimental results indicate that the 10-year expansion rate differs from the 1-year rate by approximately 1%, and under long-term ASR mitigation measures, the internal damage in the HPC is minimal, though the surface damage is more severe. As the equivalent alkali content increases, the compressive strength of the concrete cubes decreases, initially rising before falling by 5–15% over time. The HPC with only air-entraining agent added exhibited better mechanical performance than the HPC with both air-entraining and corrosion inhibitors added, with the poorest performance observed in the HPC with only a corrosion inhibitor. A relationship was established between the surface and internal damage variables, with the surface damage initially increasing rapidly before stabilizing as the internal damage rose. Numerical simulations effectively describe the damage behavior of HPC under static uniaxial compression. Comparisons with actual failure morphologies revealed that, in the cube compression tests, crack propagation directly penetrated both coarse and fine aggregates rather than circumventing them. The simulations closely matched the experimental outcomes, demonstrating their accuracy in modeling experiments. This study discusses the compressive mechanical properties of concrete under prolonged ASR through a combination of experimental and simulation approaches. It also delves into the impact of surface damage on the overall mechanical performance and failure modes of concrete. The findings provide experimental and simulation support for the concrete structures in regions with high alkali contents.

This paper comprehensively investigates the dynamic mechanical properties of concrete by employing a 75 mm diameter Split Hopkinson Pressure Bar (SHPB). To be detailed further, dynamic compression experiments are conducted on coral aggregate seawater concrete (CASC) to unveil the relationship between the toughness ratio, strain rate, and different strength grades. A three-dimensional random convex polyhedral aggregate mesoscopic model is also utilized to simulate the damage modes of concrete and its components under varying strain rates. Additionally, the impact of different aggregate volume rates on the damage modes of CASC is also studied. The results show that strain rate has a significant effect on CASC, and the strength grade influences both the damage mode and toughness index of the concrete. The growth rate of the toughness index exhibits a distinct change when the 28-day compressive strength of CASC ranges between 60 and 80 MPa, with three times an increment in the toughness index of high-strength CASC comparing to low-strength CASC undergoing high strain. The introduction of pre-peak and post-peak toughness highlights the lowest pre-to-post-peak toughness ratio at a strain rate of approximately 80 s−1, which indicates a shift in the concrete’s damage mode. Various damage modes of CASC are under dynamic impact and are consequently defined based on these findings. The LS-DYNA finite element software is employed to analyze the damage morphology of CASC at different strain rates, and the numerical simulation results align with the experimental observations. By comparing the numerical simulation results of different models with varying aggregate volume rates, it is reported that CASC’s failure mode is minimized at an aggregate volume rate of 20%.

In regions characterized by the challenging combination of brine corrosion in the salt lakes and river sand with alkali silica reaction (ASR) activity in areas of the Northwest, high-performance concrete (HPC) formulated with high-volume composite mineral admixtures as ASR suppression measures has been preferred for civil engineering structures in the region. This study investigates the splitting tensile strength, corrosion products, microscopic structure characteristics, and mesoscopic mechanical mechanisms of splitting failure of such HPC under 10-year corrosion from salt lake brine. The relationship between mechanical properties and corrosion damage, as well as the characteristics of internal crack propagation paths and failure mechanisms of HPC under splitting load, are explored. The findings reveal that as the alkali content within HPC rises, corrosion damage intensifies, resulting in a reduction in splitting tensile strength. Moreover, a linear association between mechanical properties and corrosion damage is observed. Microscopic structural analysis and numerical simulation of the splitting failure process of HPC elucidate that while the substantial presence of mineral admixtures effectively suppresses the ASR risk associated with alkali-reactive aggregates in concrete, uneven ASR gel products persist. These discontinuous micro-fine interface cracks induced by the gel products and the cracks induced by the gel products around the selective alkali-active aggregate particles distributed in the local area are the initiation sources of mortar cracks in HPC splitting failure. In terms of the overall failure state observed during the concrete splitting process, mortar cracks manifest two distinct extension paths: along the coarse aggregate interface and directly through the aggregates themselves. Notably, a greater proportion of coarse aggregates are directly penetrated by mortar cracks, as opposed to the number of interface failures bypassing coarse aggregates. More importantly, the above work establishes a theoretical reference in three dimensions: macroscopic, mesoscopic, and microscopic, for studying concrete corrosion damage in complex environments such as salt lake brine corrosion and ASR inhibition.

This study presents a comprehensive investigation into the mechanical properties of Basic Magnesium Sulfate Cement Concrete (BMSC) in comparison to Ordinary Portland Cement Concrete (OPC) within reinforced concrete components. The main objective is to evaluate BMSC’s applicability for practical engineering purposes, with a focus on its with early high strength, improved toughness, and superior crack resistance compared to conventional concrete. Experimental procedures involved fabricating beam specimens using OPC concrete with a C40 strength grade, alongside BMSC beams with varying strength grades (C30, C40, and C50). These specimens underwent bending resistance tests to analyze crack patterns and mechanical characteristics. The findings reveal that BMSC beams demonstrate enhanced bending and tensile properties at equivalent strength grades compared to OPC beams. Particularly, cracking mainly occurred at the mid-span region of BMSC beams, characterized by narrower cracks, indicating superior crack resistance. However, it was noted that the toughness of BMSC beams decreases as the strength grade increases. The maximum mid-span deflection of the BMSC test beam was smaller than that of the OPC test beam, which was 3.8 mm and 2.6 mm, respectively. The maximum crack width of the OPC beam was 4.7 times that of the BMSC beam. To facilitate practical implementation, the study developed calculation models for estimating the crack bending distance and ultimate bending distance in BMSC beams, offering valuable tools for engineering design and optimization. Overall, this research provides significant insights into the mechanical behavior of BMSC, presenting potential advantages for structural engineering applications.

Preventing the rebound of black and odorous water bodies is critical for improving the ecological environment of water bodies. This study examined the effect and underlying mechanism of in-situ improvement of the sediment microenvironment by nitrate in the tailwater of wastewater treatment plants combined with aerobic denitrifying bacteria under low-DO regulation (TailN + CFM + LDO). On the 60th day of remediation, the levels of dissolved oxygen and oxidation–reduction potential in the overlying water rose to 5.6 mg/L and 300 mV, respectively, the concentration of acid volatile sulfide within the sediment significantly decreased by 70.4%, and the organic matter content in the sediment was reduced by 62.7%, in which the heavy fraction organic matter was degraded from 105 g/kg to 56 g/kg, and the potential risk of water reverting to black and odorous conditions significantly decreased. Amplicon sequencing analysis revealed that the relative abundance of the electroactive bacteria Thiobacillus and Pseudomonas with denitrification capacity was found to be significantly higher in the TailN + CFM + LDO group than in the other remediation groups. Functional prediction of the 16S sequencing results indicated that both the quantity and activity of critical microbial enzymes involved in nitrification and denitrification processes could be enhanced in the TailN + CFM + LDO group. These results improved our understanding of the improvement of the sediment microenvironment and could thus facilitate its application.

Renewable energy transmission by high-voltage direct current (HVDC) has attracted increasing attention for the development and utilization of large-scale renewable energy under the Carbon Peak and Carbon Neutrality Strategy in China. High-penetration power electronic systems (HPPESs) have gradually formed at the sending end of HVDC transmission. The operation of such systems has undergone profound changes compared with traditional power systems dominated by synchronous generators. New stability issues, such as broadband oscillation and transient over-voltage, have emerged, causing tripping accidents in large-scale renewable energy plants. The analysis methods and design principles of traditional power systems are no longer suitable for HPPESs. In this paper, the mechanisms of broadband oscillation and transient over-voltage are revealed, and analytical methods are proposed for HPPESs, including small-signal impedance analysis and electromagnetic transient simulation. Validation of the theoretical research has been accomplished through its application in several practical projects in north, northwest, and northeast region of China. Finally, suggestions for the construction and operation of the future renewable-energy-dominated power system are put forward.

Context: Acupuncture is a promising therapy for relieving symptoms in chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS), which affects 9–16% of adult men worldwide. Objective: This study aims to explore the efficacy and safety of acupuncture for CP/CPPS. Evidence acquisition: Nine electronic databases were searched. Only randomized controlled trials were included. Two reviewers extracted data and assessed the risk of bias of trials using the revised Cochrane risk-of-bias (RoB 2.0) tool. Stata 17.0 was used to analyze the data. Evidence synthesis: Twelve trials were included. The results of a meta-analysis showed that acupuncture had larger effect sizes (standardized mean difference [SMD] = –1.20, confidence interval or CI [–1.69, –0.71], acupuncture compared with sham acupuncture; SMD = –1.01, CI [–1.63, –0.38], acupuncture compared with medication; SMD = –0.91, CI [–1.29, –0.54], acupuncture plus medication compared with medication) in reducing the National Institutes of Health Chronic Prostatitis Symptom Index (NIH-CPSI) total score. In decreasing NIH-CPSI pain domain score, acupuncture also led to larger effect sizes (SMD = –0.94, CI [–1.18, –0.70], acupuncture compared with sham acupuncture; SMD = –1.04, CI [–1.29, –0.79], acupuncture compared with medication; SMD = –0.85, CI [–1.23, –0.48], acupuncture plus medication compared with medication), whereas the effect sizes in the reduction of NIH-CPSI urinary domain and quality of life domain scores were medium. Compared with sham acupuncture and medication, acupuncture appears to be more effective in improving the global response rate. Results from four trials indicated that acupuncture was better than sham acupuncture in decreasing the International Prostate Symptom Score. No serious adverse effects were found in the acupuncture treatment. Conclusions: Current evidence supports acupuncture as an effective treatment for CP/CPPS-induced symptoms, particularly in relieving pain. Comprehensive acupuncture treatment according to individual symptoms should be considered in future clinical practice and trials for CP/CPPS. Patient summary: In this study, we further verified the efficacy of acupuncture in patients with chronic prostatitis/chronic pelvic pain syndrome, especially in reducing pain.

The contribution of municipal solid waste incineration (MSWI) to anthropogenic mercury and CO2 emissions have become increasingly important over the past decade. This study developed an inventory of anthropogenic mercury emissions and CO2 emissions during the period of 2014–2020, of MSWI process in China using a bottom-up inventory at the plant level. Overall, national MSWI anthropogenic mercury emissions increased from 2014 to 2020 by province. It was estimated that total 8321.09 kg of anthropogenic mercury emissions from 548 MSWI plants were scattered in 31 provinces of mainland China in 2020. The average intensity of mercury emission in China was 0.06 g·t−1 in 2020, which was much lower than the pre-2010 level. Furthermore, the increased CO2 emission generated by MSWI from 2014 to 2020 is 1.97 times. Anthropogenic mercury emissions and CO2 emissions were concentrated mainly in developed coastal provinces and cities. The general uncertainty of national mercury emissions and CO2 emissions was estimated to be −123% to 323% and −130% to 335%, respectively. Furthermore, future emissions were predicted from 2030 to 2060 based on different scenarios of the independent and collaborative effects of control proposals, the results indicate that the enhancement of advanced air pollution control technologies and effective management of MSWI represent pivotal factors in realizing future reductions in CO2 and mercury emissions. The findings will supplement those for mercury and CO2 emissions, and be useful for relevant policy-making and to improve urban air quality, as well as human health.

Microgrid is a group of interconnected Distributed Generators (DGs) and loads. As an application of renewable energy, microgrid began to enter people’s vision. The technology of Virtual Synchronous Generator (VSG) is becoming a research hotspot owing to it can supply inertia for distributed generation system. For the oscillation problem in microgrid after using VSG technology, this paper theoretically analyzes the variation in output frequency and power of parallel VSGs after system load fluctuation, and proposes a cooperative control method of multi-VSGs. Through distributed communication network, this method improves the output control of each VSG. In the transient process, applied method alleviates the uneven distribution in the active power of the microgrid, while reducing the difference in the output frequency of each VSG, therefore, it can significantly restrain the oscillation and ameliorate the dynamic characteristics of microgrid. A simulation model is established to prove the validity and advantage of this method at the end of this paper.

Scholars in a wide range of disciplines are interested in the casting techniques used to create the extraordinary bronze objects unearthed from the two pits of the Sanxingdui site. Although researchers have carried out a number of studies on this topic, many technical details remain unclear. This paper offers the first examination of bronze objects from the Sanxingdui site using industrial computed tomography (CT) and provides direct evidence for interpretation of the complicated casting process involved. We show that multiple pouring and various joining techniques were widely used during the casting of bronze objects from the Sanxingdui pits. The precast parts were mechanically connected with one another by the later pouring, which was the crucial technique for the casting of complicated objects. Representative features include the cast-on cramp device of the sun-shaped objects and the tenon connection with dowel found inside many branches of the bronze trees. This paper also describes evidence of core rods made of different materials, which is the earliest example of this technique in ancient China.

For China, one of its most important commitments is to realize its “3060” targets of achieving a CO2 emission peak by 2030 and carbon neutrality by 2060. However, for a developing country with heavy carbon utilization, achieving carbon neutrality in a short period necessitates tough changes. This paper briefly introduces energy and electricity scenarios and analyzes the challenges based on the current power system in China. Moreover, it summarizes the six characteristics of China’s future power grid and highlights some partially representative projects in the country.

With the ever-expanding deployment of renewable energy sources (RESs), the short-time transients have more significant impacts on shaping the characteristics of large power grids. However, the electro-mechanic transient simulation cannot reflect the short-time transients, while the current electromagnetic transient simulation cannot tackle large power systems due to the huge computational burden. This paper presents a novel simplified electromagnetic transient simulation method for large-scale power systems with high penetrations of doubly fed induction generator (DFIG)-based wind farms. Firstly, a DFIG-based wind generator (WG) model is built to simplify the detailed switching process of power electronic devices as well as reproduce external characteristics of the power system. Secondly, an initialization technique is further adopted using the power flow results, aiming to avoid the long and unnecessary computation process for starting the simulation with traditional methods. Finally, a simulation tool is developed based on the proposed method, and a real power system with 9889 buses and 898 wind farms is simulated. Results show that the simulation can start smoothly with good accuracy. Therefore, the proposed method can be employed in electromagnetic transient simulation of large-scale AC power systems with high penetrations of RESs.

IntroductionChronic heart failure (CHF) has become an increasing concern with the aging of the population. This study aims to evaluate the effectiveness and safety of Qili Qiangxin capsules (QLQX) for CHF.MethodsA systematic review and meta-analysis on clinical studies was conducted. The mechanisms of preclinical studies were summarized.ResultsWe searched six electronic databases by 20 July 2022, and finally, 7 preclinical experiments (PEs) and 24 randomized controlled trials were included. The risk of bias was accessed by the SYRCLE and RoB 2.0 tool, respectively. PEs indicated that QLQX suppresses myocardial apoptosis, inhibits renin-angiotensin-aldosterone system activation, improves water retention, and enhances cardiocyte remodeling. In clinical studies, compared with routine treatment, QLQX could improve the indicators: clinical efficacy rate (RR = 1.16, 95% CI [1.12, 1.22], GRADE: moderate), left ventricular end-diastolic dimension (SMD = −1.04, 95% CI [−1.39, −0.70], GRADE: low), left ventricular ejection fraction (SMD = 1.20, 95% CI [0.97, 1.43], GRADE: moderate), 6-minute walk distance (SMD = 1.55, 95% CI [0.89, 2.21], GRADE: low), brain natriuretic peptide (SMD = −0.78, 95% CI [−1.06, −0.51], GRADE: low), N-terminal pro-brain natriuretic peptide (SMD = −2.15, 95% CI [−3.60, −0.71], GRADE: low), and adverse events (RR = 0.46, 95% CI [0.25, 0.87], GRADE: low).DiscussionIn summary, QLQX exerts a potential mechanism of utility on myocardial apoptosis and cardiac function and has noteworthy clinical adjuvant efficacy and safety in patients with CHF.Systematic review registrationhttps://www.crd.york.ac.uk/prospero/.

Silty sand in the Yellow River flood area (YRFA) of China exhibits a low cohesive force and water-holding capacity. Its direct use for subgrade filling leads to phenomena such as subgrade bed depression, slurry, and mud. Therefore, from the perspective of waste utilization, this study investigates disposable protective clothing (DPC) and disposable nitrile gloves (DNG) produced due to COVID-19 in combination with silty sand as subgrade filling for the YRFA. Through an unconfined compressive strength and permeability test, we studied the influence of personal protective equipment (PPE) with different moisture content, concentration, and size on the strength and permeability of mixed samples. Further, we discuss its impact on the improvement of subgrade filling in YRFA. Results show that adding DPC improves both the compressive strength and ductility of the sample. However, the impermeability of the sample remains unchanged. In contrast, the addition of DNG does not increase the compressive strength and ductility of the sample at the same time, whereas it significantly improves its impermeability. The size of PPE has a considerable influence on the compressive strength of the mixed sample, whereas it does not affect the sample permeability. This method makes use of the PPE waste produced due to COVID-19, reduces environmental pollution, and provides a novel concept for improving silty sand in the YRFA.

This article summarizes the research significance and the development status of the unmanned ground tracked vehicles (UGTVs). According to the speed and steering principle of the UGTVs in plane motion, the kinematic state space equation of the vehicle is established. Based on the model predictive control (MPC), the UGTVs trajectory tracking controller is also established. After introducing the overall control system solution, based on the vehicle model, the track speed on both sides is used as the control input to solve the predicted output of the system. After constraining the control amount, the model prediction controller is established by using S function. Several simulations with different preset speeds are performed under linear conditions, and the numerical simulation with different prediction time domains and control time domains are performed under continuous curves. The test validates the effectiveness of the controller, and the effects of speed and time domain parameters on the deviation are analyzed based on the results. Based on satellite positioning technology, trajectory tracking tests of the UGTVs are carried out. After analyzing the positioning principle and common errors, the real-time kinematic technology is used to improve the positioning accuracy of the vehicle prototype. The hardware of the test platform includes a data acquisition system, a control execution system and a walking execution system, and the software part includes data processing and optimization control. The trajectory tracking experiments under different driving conditions are conducted, and the results show that the navigation tracking system can achieve good tracking performance.

Summary: Background: Pharmacological treatments for chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) are empirically used. However, the quantitative comparative effectiveness and safety of multiple pharmacological treatments is lacking. Methods: PubMed, Embase, Cochrane Central Register of Controlled Trials, and Web of Science were searched from inception to March 22, 2022. Randomised controlled trials comparing two or more oral pharmacological treatments for patients with CP/CPPS were included. Title, abstract, and full-text screening were independently screened by four reviewers. Primary outcomes were efficacy (the National Institutes of Health Chronic Prostatitis Symptom Index [NIHCPSI] total score, pain score, urinary score, and quality of life score [QoL]) and safety (adverse events). This study was registered with PROSPERO, CRD42020184106. Findings: 25 studies (3514 patients) assessed 26 treatments. Low to very low quality evidence indicated that doxazosin (Mean difference [MD], –11.4, 95% Credible interval [CrI], –17.5 to –5.1) and the doxazosin, ibuprofen, and thiocolchicoside combination (MD, –11.6, CrI, –18.1 to –5.3) were significantly more effective than placebo in the NIHCPSI total score. Other NIHCPSI relative outcomes (pain, urinary, and QoL scores) showed a similar pattern. Low and very low quality evidence suggested that combination treatment including doxazosin, ibuprofen, and thiocolchicoside (odds ratios [OR], 3.2, CrI, 0.5 to 19.3) and the tamsulosin and dapoxetine combination (OR, 6.0, CrI, 0.7 to 67.3) caused more adverse events. In half of all comparisons regarding NIHCPSI pain scores and quality of life scores, heterogeneity was minimal or low. Heterogeneity was high in both NIHCPSI total symptom scores (I2 = 78.0%) and pain scores (I2 = 87. 0%) for tamsulosin versus placebo. There was also high heterogeneity in NIHCPSI urine scores for the combination of tamsulosin and ciprofloxacin versus tamsulosin (I2 = 66.8%), tamsulosin and levofloxacin versus tamsulosin (I2 = 93.3%), and tamsulosin versus placebo (I2 = 83%). Interpretation: Pharmacological treatments have little evidence supporting efficacy in CP/CPPS. Future studies could personalise therapy for individuals according to specific symptoms and identify non-pharmacological targets for CP/CPPS. Funding: Dr Jiani Wu received funding for this project from the China Association for Science and Technology (2017QNRC001), the China Academy of Chinese Medical Sciences (ZZ13-YQ-027), and the National Natural Science Foundation of China (82105037).

As an interface between distributed power source and large power grid, microgrid has attracted more and more attention. Due to the lack of inertial support for the power system, the virtual synchronous generator (VSG) technology that can simulate the external characteristics of synchronous generators came into being. Aiming at the problem of power and frequency oscillation in microgrid after the introduction of VSG technology, this paper conducts small-signal modeling of multiple VSGs in parallel, analyzes their operating characteristics, and proposes a multiple VSGs cooperative control strategy based on adjacent information. Depend on the adjacent information, the strategy optimizes the output control of each VSG, which makes each VSG tend to the same output frequency at any time. Therefore, the proposed strategy can suppress the power and frequency oscillation, and improve the dynamic characteristics of the system. In this paper, the stability of the proposed control strategy is studied by Lyapunov stability theory, and the effectiveness of the proposed control strategy is verified by simulation.

Introduction Dyslipidaemia is a critical factor in the development of atherosclerotic cardiovascular disease. Concerning dyslipidaemia regulation, we advocate for lifestyle interventions such as diet to complement drug treatment. Numerous studies have confirmed that oat β-glucan, a critical component of oats, can help lower cholesterol. However, there is no conclusive evidence for the efficacy of oats and their products in the treatment of dyslipidaemia. As a result, we have developed this protocol to serve as a guide for future research on oat intervention for dyslipidaemias.Methods and analysis We will conduct a search of eight databases or websites (PubMed, Web of Science, Cochrane Library, EMBASE, CNKI, SinoMed, VIP and Wanfang) to identify studies on oats’ ability to regulate blood lipid levels. Two authors will screen articles independently, extract data based on inclusion and exclusion criteria, and assess the quality and bias of included studies. To assess and quantify heterogeneity, Q and I2 statistics will be used. If there is significant heterogeneity between studies, the source of the heterogeneity will be investigated using subgroup analysis and sensitivity analysis. We will analyse potential publication bias using the Begg funnel plot and Egger’s weighted regression statistics. To assess the quality of evidence for the primary outcomes, the Grades of Recommendations, Assessment, Development and Evaluation method will be used.Ethics and dissemination This study is based on the existing literature and data in the databases. It is not subject to ethical review. The findings, on the other hand, will be published in a peer-reviewed journal. These findings may aid in the management of dyslipidaemia on a daily basis.PROSPERO registration number CRD42021226751.

In this study, arsenic trioxide (ATO) was encapsulated in liposomes via copper acetate (Cu(OAc)2) gradients and high entrapment efficiency of over 80% was obtained. The average particle size and the zeta-potential of the liposomes were detected to be 115.1 ± 29.1 nm and −21.97 ± 0.6 mV, respectively. The TEM images showed rod-like precipitates in the inner aqueous phase, which was supposed be due to the formation of insoluble ATOCu complex. The in vitro drug release of ATOCu liposomes exhibited a sustained release over 72 h, and the release rates decreased with the increase of the pH of release media. Pharmacokinetic and tissue distribution studies of ATO liposomes showed significantly reduced plasma clearance rate, increased AUC0–12h and T1/2, and improved tumor distribution of As compared to iv administration of ATO solution. The anti-tumor effect of ATO loaded liposomes to S180 tumor-bearing mice was significantly improved with a tumor inhibition rate of 61.2%, meanwhile the toxicity of encapsulated ATO was greatly decreased. In conclusion, ATO can be effectively encapsulated into liposomes by remote loading method via Cu(OAc)2 gradients; the co-administration of ATO and Cu(II) via liposomal formulation may find wide applications in the treatment of various tumors.

The coordinated operation and comprehensive utilization of multi-energy sources require systematic research. A multi-energy microgrid (MEMG) is a coupling system with multiple inputs and outputs. In this paper, a system model based on unified energy flows is proposed to describe the static relationship, and an analogue energy storage model is proposed to represent the time-dependency characteristics of energy transfer processes. Then, the optimal dispatching model of an MEMG is established as a mixed-integer linear programming (MILP) problem using piecewise linear approximation and convex relaxation. Finally, the system model and optimal dispatching method are validated in an MEMG, including district electricity, natural gas and heat supply, and renewable generation. The proposed model and method provide an effective way for the energy flow analysis and optimization of MEMGs.

The contaminant of herbicide clopyralid (3,6-dichloro-2- pyridine-carboxylic acid, CLP) poses a potential threat to the ecological system. However, there is a general lack of research devoted to the perturbation of CLP to the bio-denitrification process, and its biological response mechanism remains unclear. Herein, long-term exposure to CLP was systematically investigated to explore its influences on denitrification performance and dynamic microbial responses. Results showed that low-concentration of CLP (

More than two million people live on the floodplains along the middle and lower streams of the Yellow River. The rapid development of industry and agriculture on both sides of the Yellow River has caused serious pollution of the floodplain soil. Erosion by water has led to the destruction of the floodplain which has not only compressed people’s living space but also resulted in a large amount of sediment containing heavy metals entering the river, aggravating water pollution. To further study the law governing the release of pollutants in soil, this work, based on field surveys of the Yellow River floodplain slopes from Wantan town to Liuyuankou, was focused on determining the failure mechanism and laws for the floodplain slope through the combination of a flume experiment and numerical calculations. The results showed that the floodplain slopes, composed of clay and silty sand, presented an interactive structure. Under the action of water erosion, the slope was first scoured to form a curved, suspended layer structure, and then the upper suspended layer toppled. The bank stability coefficient decreased by about 65% when the scour width increased from 0.07 m to 0.42 m, and the water content increased from 20% to 40%. For the failure characteristics, the angle of the failure surface was negatively correlated with the scour width, and the distance from the top failure surface to the bank edge was about 2.5 times that of the scour width.

Retroperitoneal liposarcoma presenting as an inguinal hernia is extremely rare without specific clinical findings and laboratory abnormalities; it might mislead the surgeon for the diagnosis and the following decision. This study is to report our experience of a large retroperitoneal liposarcoma presenting as an irreducible inguinal hernia. A 56-year-old male presented with a painless irreducible right inguinal scrotal mass without other abnormal physical examination. Preoperative computed tomography scan revealed a huge retroperitoneal mass protruding through the inguinal canal. During the operation, the tumor was en bloc removed together with the involved right testis and spermatic cord. The histopathological diagnosis was dedifferentiated liposarcoma originated from the retroperitoneum. For the patients presenting painless, slow-growing and irreducible inguinal mass, a thorough preoperative workup is crucial to rule out other likely pathologies, particularly large retroperitoneal tumor.

Abstract Background Emerging evidence demonstrates that long non-coding RNA (lncRNA) is an important regulator in tumorigenesis and development. Tubulin Alpha 4B (TUBA4B), a novel lncRNA, was recently proposed as a tumor suppressor in several human cancers. However, its role in gastric cancer (GC) remains unclear. In this study, we aimed to investigate the expression level, clinical implication, biological function and potential regulatory mechanism of TUBA4B in GC. Methods qRT-PCR was employed to detect the expression of TUBA4B in GC tissues, cell lines and plasma. In vitro and in vivo experiments were carried out using colony formation/CCK-8/transwell invasion/cell apoptosis assay and xenograft tumor model, respectively. mRNA sequencing was used to identify the TUBA4B-related downstream genes. Results TUBA4B was significantly decreased in GC tissues, cells and plasma. Low TUBA4B was positively correlated with larger tumor size, lymph node metastasis and advanced TNM stage. Moreover, TUBA4B was identified as an effective biomarker for the diagnosis and prognosis of patients with GC. Functionally, ectopic expression of TUBA4B inhibited GC cell proliferation, invasion and induced apoptosis in vitro as well as dampened tumor growth and metastasis in vivo. Furthermore, TUBA4B was found to be a competitive endogenous RNA (ceRNA) that could physically bind to and sequester miR-214 and miR-216a/b to increase the expression of their common downstream target PTEN, resulting in inactivation of PI3K/AKT signaling pathway, thereby retarding GC progression. Conclusion Our data highlight the compelling regulatory role of TUBA4B in GC, and reactivation of TUBA4B may be a promising therapeutic avenue for GC patients.

In order to study the effect of element B on the corrosion resistance of stainless steel-based flux cored wire surfacing alloy, a stainless steel surfacing layer was prepared on the surface of carbon steel plate by melt electrode gas shielded welding, and then the microstructure, electrochemical corrosion resistance, and wear resistance of the surfacing layer were analyzed. The results show that the surfacing layer of surfacing alloy presents M2B and Fe3(C, B) phases based on austenite. Boride formed in deposited metal has good corrosion resistance. Therefore, adding the proper amount of B can significantly improve the corrosion resistance of the surfacing layer. When the boron content is 2%, the corrosion resistance is the best. The minimum self-corrosion current density is 1.75766 × 10−11 mA·cm2, and the maximum self-corrosion potential is −0.254438 V. Maximum impedance curve radius. At this time, the wear resistance of the surfacing layer is also the best.

Objective. To evaluate the clinical effectiveness and safety of acupuncture therapy in the treatment of diarrhea-predominant irritable bowel syndrome (IBS-D) or functional diarrhea (FD) in adults. Method. Five electronic databases—PubMed, EMBASE, CNKI, VIP, and Wanfang—were searched, respectively, until June 8, 2020. The literature of clinical randomized controlled trials of acupuncture for the treatment of IBS-D or FD in adults were collected. Meta-analysis was conducted by Using Stata 16.0 software, the quality of the included studies was assessed by the RevMan ROB summary and graph, and the results were graded by GRADE. Result. Thirty-one studies with 3234 patients were included. Most of the studies were evaluated as low risk of bias related to selection bias, attrition bias, and reporting bias. Nevertheless, seven studies showed the high risk of bias due to incomplete outcome data. GRADE’s assessments were either moderate certainty or low certainty. Compared with loperamide, acupuncture showed more effectiveness in weekly defecation (SMD=−0.29, 95% CI [-0.49, -0.08]), but no significant improvement in the result of the Bristol stool form (SMD=−0.28, 95% CI [-0.68, 0.12]). In terms of the drop-off rate, although the acupuncture group was higher than the bacillus licheniformis plus beanxit group (RR=2.57, 95% CI [0.24, 27.65]), loperamide group (RR=1.11, 95% CI [0.57, 2.15]), and trimebutine maleate group (RR=1.19, 95% CI [0.31, 4.53]), respectively, it was lower than the dicetel group (RR=0.83, 95% CI [0.56, 1.23]) and affected the overall trend (RR=0.93, 95% CI [0.67, 1.29]). Besides, acupuncture produced more significant effect than dicetel related to the total symptom score (SMD=−1.17, 95% CI [-1.42, -0.93]), IBS quality of life (SMD=2.37, 95% CI [1.94, 2.80]), recurrence rate (RR=0.43, 95% CI [0.28, 0.66]), and IBS Symptom Severity Scale (SMD=−0.75, 95% CI [-1.04, -0.47]). Compared to dicetel (RR=1.25, 95% CI [1.18, 1.32]) and trimebutine maleate (RR=1.35, 95% CI [1.13, 1.61]), acupuncture also showed more effective at total efficiency. The more adverse effect occurred in the acupuncture group when comparing with the dicetel group (RR=11.86, 95% CI [1.58, 89.07]) and loperamide group (RR=4.42, 95% CI [0.57, 33.97]), but most of the adverse reactions were mild hypodermic hemorrhage. Conclusion. Acupuncture treatment can improve the clinical effectiveness of IBS-D or FD, with great safety, but the above conclusions need to be further verified through the higher quality of evidence.

In order to study the influencing factors of non-dissolved redox mediators on Cr (Ⅵ) bioreduction, the accelerating effect of non-dissolved redox mediators immobilized by cellulose acetate (CA) on the reduction of Cr(Ⅵ) by Escherichia coli BL21 is investigated. The results show that the accelerating order is 1-chloroanthraquinone>1,5-dichloroanthraquinone>2-chloroanthraquinone>1,8-dichloroanthraquinone>anthraquinone>1,4,5,8-tetrachloroanthtaquinone; the optimal concentration of 1-chloroanthraquinone pH and initial Cr(Ⅵ) concentration are 0.048 mol/L, 7.00 and 30 mg/L, respectively; the removal rate increases with the increasing temperature when it is in the range of 20~60 ℃; after 6 times of recycling experiments, and the Cr(Ⅵ) bioreduction rate with the immobilized 1-chloroanthraquinone maintains above 5 times of margin bacterium's. It indicates that non-dissolved redox mediators immobilized by CA can effectively accelerate the reduction rate of Cr(Ⅵ) by Escherichia coli BL21, which has favourable application value.

In order to get the optimal growth conditions of anammox bacteria, the mature-cultured anammox granule sludge is used to investigate the influencing factors. The effects of temperature, pH value, COD and influent substrate (NO-2-N and NH+4-N) on anammox bacteria activity are investigated. The results demonstrate that the optimal temperature is 40 ℃ and the optimal pH value is between 7.0~8.0 for anammox bacteria. The anammox bacteria activity is not inhibited severely when COD concentration is lower than 100 mg/L, while the denitrifying bacteria is dominant and inhibits the anammox bacteria activity when COD concentration is higher than 100 mg/L. When the influent NH+4-N and NO-2-N concentration are lower than 1 540 mg/L and 140 mg/L respectively, the anammox bacteria activity is not inhibited severely. Controlling the optimal growth conditions of anammox technical helps the rapid growth of anammox bacteria, which establishes the foundation for the rapid start-up of anammox reactor.

A novel strain, Acinetobacter bereziniae strain GWF(KM062029), was isolated from anaerobic activated sludge. The complete 16S rDNA sequence showed that strain GWF has closest homology (100%) with A. bereziniae strain BENAB7 (HE651923.1) and A. bereziniae strain ATCC 17924 (HE651922.1). Strain GWF is a Gram-negative, non-fermentative facultative anaerobe. The optimum growth conditions were shown to be 30 °C, pH 7.5 and acetate-to-perchlorate ratio of 10, respectively. In this study, anthraquinone-1-sulfonate (α-AQS) was the best redox mediator in the perchlorate reduction, and the optimum concentration range was 1.067 mmol/L. The perchlorate reduction rate was enhanced 1.33-fold using 1.067 mmol/L α-AQS. Meanwhile, strain GWF could not withstand the effect of concomitant anions (nitrate, chlorate, chlorite). The concomitant anions constants were 30 mg/L and 1.0 mmol/L for nitrate and chlorate, respectively. Chlorite completely inhibited the perchlorate reduction, and the inhibition did not depend on the concentration of chlorite.

In order to study the effect of the different ratios on the anaerobic fermentation rate is investigated, and the rate-limiting factors are preliminarily determined, at mesophilic (38±1)℃ condition, with anaerobic granular sludge as inoculums, different ratios of cow manure and corn straw are used as substrate for mixed anaerobic fermentation. By measuring daily biogas production, the concentrations of CH4 and CO2 in the marsh gas, TC, the concentration of VFAs and pH value, The results show that under the mixture ratio of 2∶1, the hydrolysis rate constants, cumulative biogas yield and biodegradability CH4 reach their high limits, which are 0.043 7 d-1, 271.93 mL/g and 71.59%, respectively. Moreover, it is found that the concentration of acetic acid is proportional to the amount of cow manure at the beginning (the first day) of mixed fermentation, and the concentration of propionicacid is proportional to the amount of corn straw in medium fermentation stage (the fifth day). In addition, rate-limiting step of biogas production is related to the ratio of cow manure and corn in fermentation material. With the increasing of corn straw proportion, on the 1st day, it tends to hydrolysis acidogenesis; from the 2th day to 15th day, it tends to hydrogen-production acetogenisis; and from the 16th day to 30th day, it is hydrolysis acidogenesis. The paper focuses on the relationship between the ratio of cow manure and corn straw and the rate-limiting step for biogas production, which could provide a theoretical and experimental support for improving the efficiency of biogas production in mixed fermentation.

In order to improve the operation performance of microbial fuel cells, improved the degradation rate of nitrate and the power output of microbial fuel cell, a typical single chamber air-cathode microbial fuel cell (AC-MFC) is inoculated and operated with urban sewage treatment plant clarifier sludge as inoculum source and sodium nitrate as electron acceptor. It is successfully started by synthetic wastewater containing a phosphate buffered nutrient solution (PBS, 50 mmol/L) and sodium acetate (1 g/L). After successful starting, the four factors of carbon source, C/N, nitrate concentration and temperature are considered to optimize the operation performance of MFC. The test result shows that the operation performance of MFC is best under the conditions of anhydrous sodium acetate as carbon source, C/N of 5∶1, 200 mg/L nitrate concentration and at 30 ℃, and the degradation rate of nitrate reaches more than 90% and the voltage of MFC is 0.462 V. After 6 cycles of operation, the voltage and power density of MFC reaches 0.62 V and 4.53 W /m2. AC impedance analysis indicates that the MFC resistance is 130 Ω. Scanning electron microscopy of electrode surface illustrates that the number of microbial species are significantly increased. The results indicate that MFC can be an effective technology for nitrate contained wastewater treatment and energy production.

The effects of six non-dissolved redox mediators (RM) immobilized in cellulose acetate beads on enhancing Cr(VI) reduction by Mangrovibacter plantisponsor CR1 were investigated. In addition, the voltammetric behaviours and electron transfer capacities of the redox mediators were examined using electrochemical methods. Compared to the control beads, the Cr(VI) bioreduction rate with 1-chloroanthraquinone cellulose acetate beads (1-CAQ/CA beads) was increased up to 4.5-fold, which was mainly attributed to enhanced electron transfer by 1-CAQ. The redox mediators also improved the oxidation–reduction potential values of the Cr(VI) bioreduction processes, which might assist in Cr(VI) bioreduction. The role of the redox mediators was discussed based on the cyclic voltammetric characteristics (E0') of the redox mediators and the electrochemical impedance spectroscopy characteristics (Rct) of the RM/CA beads. A linear correlation was found for the reaction constant k and the 1-CAQ concentration (C1-CAQ), which was k = 1.5674 C1-CAQ + 4.8506 (R2 = 0.9683). The Cr(VI) bioreduction was affected by temperature, and the optimum pH for the Cr(VI) bioreduction was 6.5. The results of repeated-batch operations showed that 1-CAQ/CA beads exhibited good stability and persistence. This study contributes to a better understanding of the effects of the redox mediator on Cr(VI) bioreduction process and demonstrates its promising potential for environmental bioremediation applications.

The denitrification characteristics of a sulfur autotrophic denitrification reactor are investigated. The results show that domestication of sulfur autotrophic bacteria is completed within 15 days after biofilm formation in the reactor, which is shorter than other similar researches. The nitrogen removal rate remains over than 90%, and the denitrification rate reaches 18.5 mg N/(L·h) with influent NO-3-N of 70 mg/L , influent pH of 8 and HRT of 4.3 h . Thiobacillus denitrificans are observed in the whole reactor when domestication finishes, while it is more abundant in the middle and lower part. The optimal influent NO-3-N concentration for the reactor is 50 mg/L, the optimal temperature is 30~35 ℃, the optimal influent pH is 7~8, and the nitrogen removal rate is over than 90%.

In this study the effect of trace elements on methanogenesis was investigated during mixed anaerobic fermentation using a single-factor experiment in the present study. The most effective concentrations of Fe0, Fe2+, Co2+ and Ni2+ that were added were 1500, 250, 0.3 and 0.6 mg/L, respectively. The optimal trace element combination was 0.58 mg/L Ni2+, 1200 mg/L Fe0 and 0.34 mg/L Co2+ by the ternary quadratic general rotary unitized design method. The degree of influence exerted by trace elements on the cumulative methane yields decreased in the order of Ni2+, Fe0 and Co2+, and the maximum CH4 yield was 241.6 mL/g volatile solids (VS), according to a regression equation. The non-dissolved organic carbon hydrolytic process showed a good fit with the first-order kinetic model. The maximum value of CH4 was 312.87 mL/g VS. Compared to the control, the bioconversion efficiencies of CH4 and CO2 production increased by 36.76% and 74.50%, respectively, at the optimal trace element combination. The obtained results provide new knowledge for improvements in the efficiency of anaerobic fermentation biogas production.

The environmental pollution of perchlorate is more and more serious because of its widely usage. Several parameters affecting perchlorate degradation are examined through batch experiments by perchlorate-degrading bacteria, which include temperature, pH, the concentration of carbon source, ClO-4, NO-3, and water-soluble and water-insoluble quinone compounds. Perchlorate-degrading bacteria is collected and enriched from a sewage treatment plant. The results suggested that the optimal conditions for perchlorate biodegradation are 30 ℃, pH 7.5~8.5 and 2.4 g/L acetate. Different NO-3 concentrations have significant effect on perchlorate biodegradation. The higher the initial concentration of ClO-4, the faster the degradation rate. The acceleration effect of AQDS is the best among dissolved quinone compounds, and the optimal concentration is 1.44 mmol/L. The acceleration effects of 1,5-dichloroanthraquinone is best among non-dissolved quinone compounds, and the optimal concentration is 0.090 mmol/L.

This study reports an analytical method for the determination of nitroimidazole and quinolones in honey using liquid chromatography-tandem mass spectrometry (LC-MS/MS). A modified QuEChERS methodology was used to extract the analytes and determine veterinary drugs in honey by LC-MS/MS. The linear regression was excellent at the concentration levels of 1–100 ng/mL in the solution standard curve and the matrix standard curve. The recovery rates of nitroimidazole and quinolones were 4.4% to 59.1% and 9.8% to 46.2% with relative standard deviations (RSDs) below 5.2% and the recovery rates of nitroimidazole and quinolones by the matrix standard curve ranged from 82.0% to 117.8% and 79% to 115.9% with relative standard deviations (RSDs) lower than 6.3% in acacia and jujube honey. The acacia and jujube honeys have stronger matrix inhibition effect to nitroimidazole and quinolones residue; the matrix inhibition effect of jujube honey is stronger than acacia honey. The matrix standard curve can calibrate matrix effect effectively. In this study, the detection method of antibiotics in honey can be applied to the actual sample. The results demonstrated that the modified QuEChERS method combined with LC-MS/MS is a rapid, high, sensitive method for the analysis of nitroimidazoles and quinolones residues in honey.

In this paper, a data driven method for Wind Turbine system level anomaly detection and root sub-component identification is proposed. Supervisory control and data acquisition system (SCADA) data of WT is adopted and several parameters are selected based on physical knowledge in this domain and correlation coefficient analysis to build a normal behavior model. This model which is based on Self-organizing map (SOM) projects higher-dimensional SCADA data into a two-dimension-map. Afterwards, the Euclidean distance based indicator for system level anomalies is defined and a filter is created to screen out suspicious data points based on quantile function. Moreover, a failure data pattern based criterion is created for anomaly detection from system level. In order to track which sub-component should be responsible for an anomaly, a contribution proportion (CP) index is proposed. The method is tested with a two-month SCADA dataset with the measurement interval as 20 seconds. Results demonstrate capability and efficiency of the proposed method.

Energy storage technologies have been rapidly evolving in recent years. Energy storage plays different roles in various scenarios. For electricity consumers, they are concerned with how to use the energy storage system (ESS) to reduce their costs of electricity or increase their profits. In this paper, a stochastic optimization method for energy storage sizing based on an expected value model for consumers with Photovoltaic Generation (PV) is proposed. Firstly, the Gaussian mixture model clustering method is used to cluster the historical load and PV data and calculate the probability of each cluster. Secondly, the optimal model of total system profit is established. Finally, according to the expected value model, the optimal ESS power and capacity are determined. Two case studies are used to demonstrate the calculation of optimal ESS capacity. The results obtained by the method proposed in this paper are compared with the results produced by the deterministic method. Through the analysis and comparison, the validity and superiority of the method proposed in this paper are verified. The profits obtained by the method proposed in this paper are 0.87% to 127.16% more than the deterministic method.

Wind turbine anomaly or failure detection using machine learning techniques through supervisory control and data acquisition (SCADA) system is drawing wide attention from academic and industry While parameter selection is important for modelling a wind turbine’s condition, only a few papers have been published focusing on this issue and in those papers interconnections among sub-components in a wind turbine are used to address this problem. However, merely the interconnections for decision making sometimes is too general to provide a parameter list considering the differences of each SCADA dataset. In this paper, a method is proposed to provide more detailed suggestions on parameter selection based on mutual information. First, the copula is proven to be capable of simplifying the estimation of mutual information. Then an empirical copulabased mutual information estimation method (ECMI) is introduced for application. After that, a real SCADA dataset is adopted to test the method, and the results show the effectiveness of the ECMI in providing parameter selection suggestions when physical knowledge is not accurate enough.