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Objective To ensure the safe operation of underground gas pipeline network near URT (urban rail transit) and to mitigate the electrochemical corrosion on the gas pipeline network caused by URT stray current, it is necessary to conduct online monitoring and analysis of URT stray current. Method Real-time continuous pipe-ground potential data from four monitoring points set up on underground gas steel pipelines near a section of Tianjin URT are obtained. A combined time-frequency domain analysis is conducted on this data. A continuous wavelet transform model is established, and a wavelet power spectrum analysis is performed. Wavelet coherence analysis is utilized to study the coherence degree and phase relationship between pipe-ground potential signals. Result & Conclusion The pipe-ground potential signals under the interference of URT stray current are a typical non-stationary signal, with certain pattern of periodic fluctuations. The intensity of these periodic fluctuations increases non-linearly as the distance to the interference source decreases. The periodically changing pipe-ground potential presents an overall waveform of a mountain-shape parabolic curve, peaking most noticeably within the 64-128 minute range. During URT operation, the coherence intensity between signals shows significant variability, with strong coherence only appearing at some intervals. Additionally, the leading or lagging angles of the inter-signal phase correspond to the operation intervals of URT trains.

Peatlands are important carbon pools and stable carbon sinks in terrestrial ecosystems. Studying carbon storage and accumulation characteristics can provide a scientific basis for the conservation and restoration of peatlands. Based on the 2014–2015 survey of the Jilin Provincial Forestry Department on the carbon storage of peatlands in the Changbai Mountains, the surveyed 865 peatlands have a total area of 22,900 hm2 and carbon storage of 18,753,300 tons. There are 275 medium‐sized organic carbon (OC) stocks of peatlands (10000–100,000 tons) in this area, and their carbon storage accounts for 41.3% of the total reserves. The peatland carbon in this area is mainly distributed in the Yanbian Korean Autonomous Prefecture, valleys and the lava platform are the most important geomorphological basis for peatland deposits. The Mudanjiang River Basin has the largest carbon storage and it is dominated by a nutrient‐rich peatland. Peatlands in the Changbai Mountains formed and developed since the Holocene, and the carbon accumulation intensity is different in each stage. The average carbon density of peatlands in this area was 69.74 kg/m3 with an average value of 81.77 kg/m2 for OC accumulation per unit area. The average value of the carbon cumulative intensity of peatlands was 164.43 ton/km2 and the carbon accumulation rate of peatlands was 38.96 g/(a m2). [ABSTRACT FROM AUTHOR]

Loss‐of‐control effectiveness is a common fault in the engineering field. In the existing adaptive fault‐tolerant control algorithms, observers and Lyapunov functions are often used to estimate fault parameters. However, they can only ensure the convergence of fault parameters as time goes to infinity. This leads to the fact that the controller can only play a better fault‐tolerant role in the steady‐state process, and cannot guarantee the system performance in the transient state. Therefore, a dual fault‐tolerant control (DFTC) algorithm is proposed for a class of stochastic systems with partial loss‐of‐control effectiveness. The algorithm introduces a fault‐tolerant objective on the basis of the control objective. By establishing a new objective function, the controller is forced to have the characteristics of active learning to improve the transient performance of the fault system. An example simulation verifies the validity of DFTC. The simulation results show that DFTC can drive the system to the desired output, especially when partial loss‐of‐control efficiency occurs in the system, it can learn the unknown parameters actively, quickly, and accurately, which is significantly better than the conventional control based on the certainty equivalence principle and improves the reliability of the system. [ABSTRACT FROM AUTHOR]

[Display omitted] • A variable universe fuzzy PID control algorithm is proposed for the superheat. • The combined model of electronic expansion valve and evaporator is established. • Simulation and experimental verification are implemented. • The proposed control method has strong robustness and fast regulation. Gas engine heat pump (GEHP) is more and more widely used in various commercial buildings and residential buildings because of its advantages of high efficiency, energy saving and environmental protection. However, unstable superheat is easy to cause unstable operation of GEHP system, resulting in lower energy efficiency and unnecessary energy waste. Therefore, to achieve the reliable control of superheat, a variable universe fuzzy Proportional-Integral-Differential (PID) control method is proposed in this study. First, the combined control model of electronic expansion valve (EEV) and evaporator is established. A step response curve of superheat to the opening of EEV and the parameters of the control model are obtained by experiment. In addition, simulation of the proposed control method has been performed and compared with other two methods to evaluate the control performance. Meanwhile, the proposed control method is applied to the test bench for superheat control. The results showed that the fluctuation of superheat after reaching the steady state under the control method was kept within 0.3 °C, and the superheat could return to the steady state in a short time after being disturbed. Both simulation and experiment results indicate that the proposed control method has strong robustness and fast regulation. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to evaluate changes in ultrafast pulse wave velocity (ufPWV) in individuals with arterial stiffness and subclinical atherosclerosis (subAS), and to provide cutoff values., Methods: This retrospective study recruited 231 participants, including 67 patients with subAS. The pulse wave velocity was measured at the beginning and end of systole (PWV-BS and PWVES, respectively) using ultrafast ultrasonography to assess arterial stiffness. The right and left common carotid arteries were measured separately, and laboratory metabolic parameters were also collected. Participants were balanced between groups using propensity score matching (PSM) at a 1:1 ratio, adjusting for age, sex, and waist-to-hip ratio as potential confounders. Cutoff values of ufPWV for monitoring subAS were determined via receiver operating characteristic (ROC) curve analysis., Results: PWV-ES, unlike PWV-BS, was higher in the subAS subgroup than in the subAS-free group after PSM (all P<0.05). For each 1 m/s increase in left, right, and bilateral mean PWV-ES, the risk of subAS increased by 23% (95% confidence interval [CI], 1.04 to 1.46), 26% (95% CI, 1.07 to 1.52), and 38% (95% CI, 1.12 to 1.72), respectively. According to ROC analyses, predictive potential was found for left PWV-ES (cutoff value=7.910 m/s, P=0.002), right PWV-ES (cutoff value=6.615 m/s, P=0.003), and bilateral mean PWV-ES (cutoff value=7.415 m/s, P<0.001), but not for PWV-BS (all P>0.05)., Conclusion: PWV-ES measured using ultrafast ultrasonography was significantly higher in individuals with subAS than in those without. Specific PWV-ES cutoff values showed potential for predicting an increased risk of subAS.

Background: The mortality and disability of chronic kidney disease (CKD) are highly linked to the incidence of atherosclerotic cardiovascular events. Numerous clinical biochemical indicators of renal function often only increase in advanced stages of CKD, driving an urgent need for reliable indicators of atherosclerosis in early CKD. Ultrafast pulse wave velocity (ufPWV) can evaluate the stiffness of the straight carotid in vivo and quantitatively reflect the degree of early atherosclerosis. However, the use of ufPWV in CKD has not yet been reported. In this study, we aimed to explore the association between carotid stiffness, quantified using ufPWV, and renal function in CKD patients., Methods: This cross-sectional study enrolled a total of 582 participants between March 2017 and May 2022 in the Affiliated Hospital of Nanjing University of Traditional Chinese Medicine. Among those, 205 individuals without a history of CKD and estimated glomerular filtration rate (eGFR) ≥90 mL/min/1.73 m 2 were included as controls. According to the Kidney Disease Outcomes Quality Initiative (K/DOQI) expert group of the American Kidney Foundation staging for CKD, 44 stages 1 and 2 CKD patients were included in the early CKD group, whereas 49 stages 3, 4, and 5 CKD patients were included in the advanced CKD group. Clinical and serum parameters, ultrasonic characteristics including carotid intima-media thickness (cIMT), and pulse wave velocity at the beginning of systole (PWV-BS) and pulse wave velocity at the end of systole (PWV-ES) of systole were analyzed. One-way analysis of variance (ANOVA) and least significant difference (LSD) tests were performed to compare cIMT, PWV-BS, and PWV-ES among subgroups in pairs. Pearson's correlation analysis, scatter plots, and subgroups correlation analysis were used to determine the relationships among ultrasound characteristics (cIMT, PWV-BS, PWV-ES), and major cardiovascular risk factors., Results: PWV-BS and PWV-ES for the early and advanced CKD groups were significantly higher than those for controls (all P<0.05). PWV-ES had the greatest correlation with age (r=0.474, P<0.001). PWV-ES had the greatest increase with age in the early CKD group (r=0.698, P<0.001)., Conclusions: ufPWV can be used for the quantitative evaluation of carotid stiffness in CKD patients. PWV-ES may be more advantageous in the assessment of carotid atherosclerosis in early CKD patients., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://qims.amegroups.com/article/view/10.21037/qims-23-503/coif). The authors have no conflicts of interest to declare., (2024 Quantitative Imaging in Medicine and Surgery. All rights reserved.)

CAG is the most common precancerous disease of gastric cancer, which belongs to a kind of chronic gastritis. CAG is in close association with gastric cancer, which makes itself a critical node clinically in cancer prevention and treatment. Curcumol is a main active monomer in Fuzheng Huowei decoction, which has the properties of antioxidant, antiviral, and antitumor. In this study, the expression of SDF-1 α /CXCR4/NF- κ B was detected by in vivo and in vitro methods. Then, we found that the expressions of NF- κ B, SDF-1 α , CXCR4, and p-NF- κ B were decreased in the curcumol treatment group. Curcumol inhibited gastric cancer cells' viability, migration, and invasion and induced their apoptosis. After adding the lentivirus overexpressing SDF-1 α to the curcumol treatment group, it was found that SDF-1 α , CXCR4, NF- κ B, and p-NF- κ B protein expressions were all increased, and the effect of curcumol on gastric cancer cells was reversed. In the nude mouse experiment, the tumor volume in the curcumol + SDF-1 α group was the largest, and the tumor volume in the Fuzheng Huowei decoction + NC group was the smallest. In conclusion, curcumol effectively protects gastric tissue and inhibits the viability of gastric cancer cells, and curcumol regulates SDF-1 α /CXCR4/NF- κ B to play a therapeutic role in chronic atrophic gastritis and gastric cancer., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2022 Xuehui Ma et al.)

CAG is an essential procession of the transformation from gastritis into gastric cancer. A series of timely moves of diagnosis, treatment, and monitoring towards CAG to anticipate the potential population at risk of gastric cancer is an effective means to prevent gastric cancer occurrence. The main active monomer in Fuzheng Huowei Decoction is Curcumol, which is an indispensable ingredient in the treatment to CAG and gastric cancer. In this study, the CAG model, in vitro cultured gastric cancer cells, and participating nude mice were treated with Curcumol, and alterations in SDF-1 α /CXCR4/VEGF expression were estimated using the assays of immunohistochemistry and Western blot. MTT, flow cytometry, transwell, HE staining, and tumor volume determination were applied for the verification of the regulatory effects of Curcumol on CAG and gastric cancer cells. The results showed that the expressions of VEGF, SDF-1 α , CXCR4, and CD34 decreased in our CAG model with Curcumol treatment. Curcumol is in procession of an inhibitory effect toward the activity, migration, and invasion of gastric cancer cells, and it would also result in gastric cancer cells' apoptosis. We subsequently added SDF-1 α overexpressing lentivirus to the Curcumol-treated group and found that the expressions of SDF-1 α , CXCR4, and VEGF protein increased, and the inhibitory effect of Curcumol on gastric cancer cells was withdrawn. Our nude mouse experiment showed that Curcumol + SDF-1 α group ended up with the largest tumor volume, while Fuzheng Huowei + NC group was with the smallest tumor volume. In conclusion, Curcumol is able to effectively protect the gastric tissue and suppress gastric cancer cells' viability. Curcumol functions as a therapeutic factor in chronic atrophic gastritis and gastric cancer by downregulating SDF-1 α /CXCR4/VEGF expression., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2022 Xuehui Ma et al.)