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Objective: Neutrophil-to-lymphocyte ratio (NLR) has been shown to be an independent predictor for cardiovascular diseases and metabolic diseases. The role of NLR in metabolic syndrome (MS) has also been explored albeit with conflicting results. The objective of this study was to assess the predictive role of NLR in MS. Methods: We conducted a meta-analysis of observational studies to evaluate the predictive role of NLR in MS. Cochrane library, PubMed, Medline, Embase, and Scopus were systematically searched from their inception to December 2023. The Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) guidelines was followed. The statistical analysis was performed using RevMan 5.3 software. A randomeffect model was used. Results: Twenty six studies enrolling 70,937 individuals were included in this meta-analysis. Compared with the individuals without MS, NLR value was significantly higher in the patients of MS (mean difference (MD) 0.40, 95% confidence intervals (CI): 0.27–0.52, P < 0.00001, I2 = 97%). The derived NLR value also was significantly higher in participants with MS than those without MS (MD 0.48, 95%CI: 0.13–0.84, P = 0.007, I2 = 96%). There was no statistically significant association for NLR between the patients with 4 metabolic risk factors (MRF) and those with 3 MRF, or between patients with 5 MRF and those with 4 MRF (MD 0.16, 95%CI: -0.02-0.35, P = 0.10, I2 = 84%; MD 0.12, 95%CI: -0.06-0.29, P = 0.20, I2 = 68%). However, MS patients with 5 MRF had a significantly higher mean NLR value than those with 3MRF (MD 0.37, 95%CI: 0.05–0.68, P = 0.02, I2 = 92%). Compared with the individuals with low NLR, incidence of MS was significantly higher in those with high NLR (OR 2.23, 95%CI: 1.25–3.98, P = 0.006, I2 = 97%). Conclusion: The findings of our meta-analysis suggested that the value of NLR and derived NLR were higher in MS patients. MS patients with 5 MRF had a significantly higher mean NLR value. High NLR also demonstrated a significantly increased the incidence of MS. NLR may be a good predictive biomarker in MS. [ABSTRACT FROM AUTHOR]

The spatiotemporal variations in suspended sediment concentration (SSC) in the lower reaches of the Yellow River exhibit significant variability and are influenced by reservoir operations. Understanding the spatiotemporal distribution characteristics of SSC in water holds crucial implications for environmental protection and reservoir operation management. Based on daily-scale SSC monitoring data from four hydrological stations in the lower Yellow River, this study established an SSC remote sensing model applicable to Landsat series satellite data. The independent variable of the model, Rrs(NIR)/(Rrs(G) + Rrs(R) + Rrs(SWIR)), demonstrated sensitivity to water bodies with different SSC values. Distinctive spatiotemporal characteristics in sediment transport were observed across the lower Yellow River. Spatially, the SSC values in the Sanmenxia and Xiaolangdi reservoirs were notably lower than those in other river sections, averaging 1008.42 ± 602.83 mg/L and 1177.89 ± 627.95 mg/L, respectively. Over time, the majority of the river sections (96%) exhibited decreasing trends in SSC during 1984–2022, particularly in the downstream Xiaolangdi reservoir, with average SSC values of 4265.58 ± 1101.77 mg/L in the 1980s and 1840.80 ± 2255.15 mg/L in the 2020s. Seasonal variations in SSC were prominent, with higher summer concentrations, averaging 5536.43 ± 2188.77 mg/L (2020s summer) and 814.11 ± 158.27 mg/L (2020s winter). Reductions in SSC during 1984–2022 primarily occurred in summer, weakening its seasonal variability in the lower Yellow River. Water discharge emerged as a critical factor influencing suspended sediment transport, with SSC increasing in high-water-flow months. Following the construction of the Xiaolangdi reservoir, the relationship between SSC and water discharge at different stations underwent notable alterations. This study enhances our understanding of the spatiotemporal dynamics of suspended sediment transport in the lower Yellow River, providing valuable insights for utilizing long-term Landsat series data in the dynamic monitoring of river sediment transport. [ABSTRACT FROM AUTHOR]

The study of river sediment is a broad and complex field. One of the very important parameters is suspended particle size (SPS), which is indispensable for understanding water–sediment dynamics. As one of the most serious soil erosion areas in the world, the Loess Plateau delivers a large amount of sediment to the Yellow River and its numerous tributaries. Studies on riverine SPS in the Loess Plateau have received extensive attention. In this study, we investigate the spatiotemporal variations of SPS in the Loess Plateau rivers and analyze the driving factors along with their relative importance. Through the analysis of SPS data from 62 hydrological stations, the results indicated the spatial distribution of SPS was similar in the 1980s and 2010s, with both coarser particles mainly distributed in the northern rivers and finer particles mainly distributed in the southern rivers. During the 1980s to the 2010s, the mean SPS on the Loess Plateau decreased from 33 μm to 20 μm, with mean reductions of 42.0%, 29.4%, 46.3%, and 36.8% in the northern, western, southwestern, and southeastern basins, respectively. The most significant changes in SPS were observed in the Kuye, Wuding and Jalu River basins in the northern region, with decreases ranging from 27 to 73 μm. In the 1980s, topography (slope) and human management, followed by precipitation, were the key factors affecting SPS variability, contributing 25.7%, 25.9% and 24.0%, respectively. In the 2010s, the explanatory power of topographic slope on SPS variability declined by 16.6%, and other natural factors no longer significantly influenced SPS variability. The results of this study can serve as a reference for integrated basin management and sustainable ecosystem development in river catchments around the world. [ABSTRACT FROM AUTHOR]

Shield tunnels, especially those with small curvature radii, are currently used in the construction of underground rail transit, and they provide important support for the future development and utilization of underground space. Generally, tunnel curvature radii no more than 350 m are considered small, and the corresponding tunnel mechanical properties are more complex than those of a straight tunnel, introducing unprecedented challenges to shield construction. Therefore, the main load types that affect the mechanical properties of shield tunnel segments with small curvature radii are summarized. Based on the Wugensong–Guangdu shield zone in the Chengdu metro No. 1 southward line, the shield machine in this area adopts passive articulation system, in situ monitoring of the segment strain and the gap between rings is conducted, and the indoor model uniaxial compression testing is performed considering only the jack thrust as the longitudinal load. The results show that the segment strain and the gap between rings are mainly affected by the jack thrust, and the axial strain is twice the circumferential strain. In the construction of shield tunnels with small curvature radii, segment damage is more likely to occur on the outer side of the tunnel axis than on the inner side. For a shield tunnel of a certain curvature, the construction difficulty during driving increases in the order of the straight line section, in (out)-curve section and full-curve section. For the same propulsion stage, the smaller the curvature radius is, the easier the segment can be damaged. These research results are of great significance to the safe construction of shield sections with curvature radii for underground rail transit in the future. Highlights: The main load types that affect the mechanical properties of small curvature shield tunnel segments were summarized. The strain and gap at different monitoring positions during the whole construction process were monitored on the engineering scale. Through the designed "side V-shaped" loading test, the mechanical characteristics of segments with different small curvature radii in different stages were analyzed. [ABSTRACT FROM AUTHOR]

The clustered regularly interspaced short palindromic repeats (CRISPR) system is a promising platform for nucleic acid detection. Regulating the CRISPR reaction would be extremely useful to improve the detection efficiency and speed of CRISPR diagnostic applications. Here, we have developed a light‐start CRISPR‐Cas12a reaction by employing caged CRISPR RNA (crRNA). When combined with recombinase polymerase amplification, a robust photocontrolled one‐pot assay is achieved. The photocontrolled one‐pot assay is simpler and is 50‐fold more sensitive than the conventional assay. This improved detection efficiency also facilitates the development of a faster CRISPR diagnostic method. The detection of clinical samples demonstrated that 10–20 min is sufficient for effective detection, which is much faster than the current gold‐standard technique PCR. We expect this advance in CRISPR diagnostics to promote its widespread detection applications in biomedicine, agriculture, and food safety. [ABSTRACT FROM AUTHOR]

The clustered regularly interspaced short palindromic repeats (CRISPR) system is a promising platform for nucleic acid detection. Regulating the CRISPR reaction would be extremely useful to improve the detection efficiency and speed of CRISPR diagnostic applications. Here, we have developed a light‐start CRISPR‐Cas12a reaction by employing caged CRISPR RNA (crRNA). When combined with recombinase polymerase amplification, a robust photocontrolled one‐pot assay is achieved. The photocontrolled one‐pot assay is simpler and is 50‐fold more sensitive than the conventional assay. This improved detection efficiency also facilitates the development of a faster CRISPR diagnostic method. The detection of clinical samples demonstrated that 10–20 min is sufficient for effective detection, which is much faster than the current gold‐standard technique PCR. We expect this advance in CRISPR diagnostics to promote its widespread detection applications in biomedicine, agriculture, and food safety. [ABSTRACT FROM AUTHOR]

Considering the complexity of the three-dimensional environment and the flexibility of the quadrotor aircraft, using the traditional A* algorithm for global path planning has the disadvantages of less search direction, more expanded nodes, and a longer planning path. Therefore, an improved A* algorithm is proposed, which is improved from two aspects. Firstly, a two-layer extended neighborhood strategy is proposed, which can increase the search direction and make better use of the flexibility of the aircraft. Secondly, the heuristic function is improved to make the heuristic function value closer to the actual planning path distance, which can reduce the expansion nodes and optimize the planning path. Finally, the path planning simulation of the improved A* algorithm is carried out and the results show that the path planned by the improved algorithm is shorter and the expanded nodes are fewer, which can guide the quadrotor to reach the destination better. [ABSTRACT FROM AUTHOR]

In this paper, a parallel Image-based visual servoing/force controller is developed in order to solve the interaction problem between the collaborative robot and the environment so that the robot can track the position trajectory and the desired force at the same time. This control methodology is based on the image-based visual servoing (IBVS) dynamic computed torque control and couples the force control feedback in parallel. Simulations are performed on a collaborative Delta robot and two types of image features are tested to determine which one is better for this parallel IBVS/force controller. The results show the efficiency of this controller. [ABSTRACT FROM AUTHOR]

Background and Aim: Vasculogenic mimicry (VM) is a unique blood supply pattern in malignant tumors that is closely associated with metastasis and poor prognosis. The Hippo signaling effector TAZ is upregulated in several cancers, promoting cancer proliferation and metastasis. This study aimed to identify the function of TAZ and its regulatory mechanism in promoting VM in gastric cancer (GC). Methods: The expression of TAZ and TEAD4 and their correlations with overall survival and VM‐related markers were analyzed in 228 cases of GC. The regulatory mechanism of TAZ and its interaction with TEAD4 in epithelial‐mesenchymal transition (EMT) and VM were investigated in vitro and in vivo. Results: TAZ was highly expressed in GC samples and was associated with shorter patient survival time. TAZ expression was positively correlated with TEAD4 and VM in patients with GC. TAZ enhanced the migration and invasion capacity of GC cells through EMT in vitro and upregulated the expression of VM‐associated proteins, including VE‐cadherin, MMP2, and MMP9, thus promoting VM formation. Overexpression of TAZ accelerated the growth of subcutaneous xenograft and promoted VM formation in vivo. Co‐immunoprecipitation assays showed that TAZ can directly bind to TEAD4, and in vitro experiments showed that this binding mediates the function of TAZ in regulating EMT and VM formation in GC. Conclusions: TAZ promotes GC metastasis and VM by upregulating TEAD4 expression. Our findings expand the role of TAZ in VM and provide new theoretical support for the use of antiangiogenic therapy in the treatment of advanced GC. [ABSTRACT FROM AUTHOR]

Background: Hepatocellular carcinoma (HCC) often presents with satellite nodules, rendering current curative treatments ineffective in many patients. The heterogeneity of HCC is a major challenge in personalized medicine. The emergence of spatial transcriptomics (ST) provides a powerful strategy for delineating the complex molecular landscapes of tumours. Methods: In this study, the heterogeneity of tissue-wide gene expression in tumour and adjacent nonneoplastic tissues using ST technology were investigated. The transcriptomes of nearly 10,820 tissue regions and identified the main gene expression clusters and their specific marker genes (differentially expressed genes, DEGs) in patients were analysed. The DEGs were analysed from two perspectives. First, two distinct gene profiles were identified to be associated with satellite nodules and conducted a more comprehensive analysis of both gene profiles. Their clinical relevance in human HCC was validated with Kaplan–Meier (KM) Plotter. Second, DEGs were screened with The Cancer Genome Atlas (TCGA) database to divide the HCC cohort into high- and low-risk groups according to Cox analysis. HCC patients from the International Cancer Genome Consortium (ICGC) cohort were used for validation. KM analysis was used to compare the overall survival (OS) between the high- and low-risk groups. Univariate and multivariate Cox analyses were applied to determine the independent predictors for OS. Results: Novel markers for the prediction of satellite nodules were identified and a tumour clusters-specific marker gene signature model (6 genes) for HCC prognosis was constructed. Conclusion: The establishment of marker gene profiles may be an important step towards an unbiased view of HCC, and the 6-gene signature can be used for prognostic prediction in HCC. This analysis will help us to clarify one of the possible sources of HCC heterogeneity and uncover pathogenic mechanisms and novel antitumour drug targets. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to explore the effects of entrepreneurship education by examining the influences of the curriculum system, teaching team, design of practical programs, and the institutional systems on universities' entrepreneurial education performance. Design/Methodology/Approach: This paper employs a case-based approach—Qualitative Comparative Analysis (QCA). Data were collected from 12 universities that were typical cases in the implementation of entrepreneurial education. The four dimensions of entrepreneurship education are applied as conditional indicators. fsQCA3.0 software is used to analyze the necessary conditions and condition combination of the truth table. Findings: There are three sets of condition combinations of the intermediate solution that results in a high level of entrepreneurial education performance: (1) when the credit ratio of entrepreneurship courses is higher and there are more practical platform platforms, even if the entrepreneurship education system and mechanism is less mature, the level of entrepreneurial education performance is high; (2) with a higher credit ratio of entrepreneurship courses, higher quality of teaching teams, and higher standard of practical platforms, the level of entrepreneurial education performance is high; (3) with a higher level of credit ratio of entrepreneurship courses and more practical platforms, as well as mature entrepreneurship education system and mechanism, even if the quality of the teaching team is lower, the level of entrepreneurial education performance is satisfied. Research Limitations/Implications: The dimensions of entrepreneurship education can be expanded; additionally, given that there are many other factors affecting entrepreneurial performance, it is necessary to identify and integrate other possible factors on an ongoing basis. Practical Implications: This study offers practical implications for universities and policy makers that can promote the transformation of theoretical knowledge into practice in the field of entrepreneurship in colleges and universities. Social Implications: This study is one of the first to empirically examine the effect of institutional-driven entrepreneurship education in developing countries. The enhancement of entrepreneurship education can benefit the development of individuals and schools, and even has a potential impact on the progress of the country and society as a whole. Originality/Value: This study emphasizes the significance of viewing the entrepreneurial education as a multi-dimensional concept by targeting different kinds of players. Furthermore, it employs a case-based approach to identify configurations of the antecedent attributes of the curriculum system, teaching team, design of practical programs, and the institutional systems, and their influence on universities' entrepreneurial education performance. [ABSTRACT FROM AUTHOR]

The structure of current collectors has significant effects on the performance of a lithium-ion battery (LIB). In this study, we use copper fiber felts made by multi-tooth cutting and high-temperature solid-phase sintering as the current collector for LIBs. An integrated porous electrode based on CuO nanoflowers/copper fiber felt is developed for the anode. Results suggest that the reversible capacity and cycle stability of this new anode are significantly improved, compared with the pristine bare-surface copper plate under the same condition of rate cycles. The new anode structure based on the copper-fiber felt with a porosity of 60% exhibits a higher performance with an initial specific capacity of 609.5 mAh g−1 and retains 486.1 mAh g−1 after 200 cycles at a current density of 0.5 C. The improved electrochemical performance of this electrode is attributed to its large surface area of CuO nanoflowers and porous structure of the copper fiber felt, due to enhanced contact between the active material of CuO nanoflowers and electrolyte. This pore-rich structure makes the electrolyte easy to permeate into the electrode, shortens the diffusion path of Li+, reduces the internal resistance and alleviates the volume expansion of the active material during the insertion and desertion processes of Li+. [ABSTRACT FROM AUTHOR]

Recent studies have reported a relationship between the platelet to lymphocyte ratio (PLR) and acute coronary syndromes. The aim of the present study was to investigate the association between PLR and stable coronary artery disease (CAD). A systematic search was conducted based on electronic databases (Cochrane, PubMed, Elsevier, Medline, and Embase). A total of 14 studies (n = 4,871) were included in the meta-analysis. Compared with the non-CAD group, PLR was significantly higher in CAD group (P =.002). After further classification according to the Gensini score, the cases with atherosclerosis demonstrated a higher PLR than those without atherosclerosis (P <.001). Platelet to lymphocyte ratio was higher in the severe atherosclerosis group compared with the mild atherosclerosis group (P <.001). Compared with the poor coronary collateral circulation (CCC) group, PLR was significantly lower in the good CCC group (P <.001). The PLR was significantly higher in patients with coronary slow flow (CSF) than those with normal coronary flow (P =.01). On the basis of current evidence, an elevated PLR was associated with stable CAD, and it might be useful for predicting CAD severe stenosis, collateral circulation, and CSF. Future studies are needed to clarify the relationship between PLR and stable CAD. [ABSTRACT FROM AUTHOR]

Diffuse glioma is the deadliest form of brain cancer, and the median survival of grade IV glioma (glioblastoma, GBM) is no more than 2 years even with maximal surgical resection followed by radiotherapy and chemotherapy, which are now the standard of care for GBM. Glioma shares common characteristics with most malignant tumours, such as invasiveness, rapid progression, resistance to various therapies and inevitable recurrence, while it also has its own unique features, such as high aggressiveness and immunotherapy resistance, which can be, respectively, attributed to epithelial-mesenchymal transition (EMT) and the immunosuppressive microenvironment. Here, we calculated the EMT score of glioma using The Cancer Genome Atlas (TCGA), the Chinese Glioma Genome Atlas (CGGA) and the Gene Expression Omnibus (GEO) datasets and validated its prognostic value. Then, we investigated its role in the glioma immune microenvironment, identified the enriched EMT-related immune genes and determined their specific biological functions in glioma. Furthermore, clinical relevance analysis showed the translational value of these EMT-related immune genes. In short, our findings reveal a critical link between EMT and the glioma immune microenvironment and offer important clues for further investigation of the underlying molecular mechanism. [ABSTRACT FROM AUTHOR]

Objective: Recent studies have reported that neutrophil-to-lymphocyte ratio (NLR) is associated with cardiovascular disease. The aim of the present study was to investigate the prognostic value of NLR in aortic disease.Methods: We systematically searched electronic databases (Cochrane, PubMed, Elsevier, Medline, and Embase) from their inception to March 2020. Observational studies that evaluated the relationship between NLR and aortic disease were eligible for critical appraisal. Data were extracted from applicable articles, risk ratio (RR), weighted mean differences (MD) and 95% confidence intervals (CI) were calculated by RevMan 5.3, and statistical heterogeneity was assessed by the I2 statistic.Results: Fourteen studies enrolling 4066 individuals were included in the meta-analysis. Compared with the control group, NLR was significantly higher in the aortic disease group (MD 3.44, 95%CI: 0.81-6.07, P = 0.01, I2 = 99%). The NLR was also significantly higher in non-survivors with aortic disease, compared to the survivors (MD 4.62, 95%CI: 2.75-6.50, P < 0.00001, I2 = 60%). Compared with the aortic disease patients with a low NLR, mortality was significantly higher in those with a high NLR (RR 2.63, 95%CI: 1.79-3.86, P < 0.00001, I2 = 67%).Conclusion: Based on current evidence, an elevated NLR was associated with aortic disease and in-hospital mortality. Raised NLR also demonstrated a significantly increased the risk of mortality after surgical repair in aortic disease patients. NLR may be a good prognostic biomarker in aortic disease and deserve further research in this area. [ABSTRACT FROM AUTHOR]

The up‐regulation of EMT regulator Twist1 has been implicated in vasculogenic mimicry (VM) formation in human triple‐negative breast cancer (TNBC). Twist1 targets the Claudin15 promoter in hepatocellular carcinoma cells. Claudin family members are related with TNBC. However, the relationship between Claudin15 and VM formation is not clear. In this study, we first found that Claudin15 expression was frequently down‐regulated in human TNBC, and Claudin15 down‐regulation was significantly associated with VM and Twist1 nuclear expression. Claudin15 down‐regulation correlated with shorter survival compared with high levels. Claudin15 silence significantly enhanced cell motility, invasiveness and VM formation in the non‐TNBC MCF‐7 cells. Conversely, an up‐regulation of Claudin15 remarkably reduced TNBC MDA‐MB‐231 cell migration, invasion and VM formation. We also showed that down‐regulation of Claudin15 was Twist1‐dependent, and Twist1 repressed Claudin15 promoter activity. Furthermore, GeneChip analyses of mammary glands of Claudin15‐deficient mice indicated that Claudin18 and Jun might be downstream factors of Twist1‐Claudin15. Our results suggest that Twist1 induced VM through Claudin15 suppression in TNBC, and Twist1 inhibition of Claudin15 might involve Claudin18 and Jun expression. [ABSTRACT FROM AUTHOR]

Summary: This paper studies the event‐triggered H∞ control for synchronization of networked switched master‐slave systems under external disturbance, stochastic attacks, and quantization. With the proposed event‐triggering schemes, the communication frequency and data packets can be effectively regulated and reduced. To reduce further the burden of network transmission, the quantized control is applied. Moreover, the network transmission delay and the stochastic cyberattacks are concerned. In addition, the synchronization problem between switched master systems and switched slave systems is transformed into a stability problem of switched error systems. By adopting multiple Lyapunov functions and average dwell time method, sufficient conditions are constructed to assure the mean‐square exponential stability with H∞ performance of the switched error systems. Meanwhile, the stagger between data switching instants and triggering instants is discussed in the system in detail. Accordingly, the controller gains and event‐triggering parameters are obtained utilizing a set of linear matrix inequalities. Finally, a numerical simulation and a practical example are illustrated to demonstrate the effectiveness of the presented method. [ABSTRACT FROM AUTHOR]

Background and aims: HOXD antisense growth-associated long noncoding RNA (HOXD-AS1) was reported to be upregulated in various cancers, such as gastric cancer, hepatocellular carcinoma, colorectal cancer, and glioma. Here, we conducted a meta-analysis and The Cancer Genome Atlas data review to investigate the clinicopathologic and prognostic value of HOXD-AS1 in patients with malignant tumors. Materials and methods: Systematic literatures were searched from PubMed, Medline, Cochrane Library, Web of Science, EMBASE database, Ovid, Chinese CNKI, and the Chinese WanFang database. The role of HOXD-AS1 in cancers was evaluated by pooled ORs and HRs with 95% CIs. The Cancer Genome Atlas dataset was used to explore the prognostic value of HOXD-AS1 in various cancers. Results: Fifteen studies with 1,678 patients were included in this meta-analysis. The results indicated that HOXD-AS1 was associated with tumor size, differentiation, lymph node metastasis, and TNM stage. Moreover, the high HOXD-AS1 expression indicated a poor overall survival (OS) rate and can be an independent predictive factor for OS. The TCGA dataset, which included 9,502 cancer patients, showed that the expression of HOXD-AS1 was related to poor OS and disease-free survival. We also analyzed the prognostic role in different kinds of cancers such as digestive cancers, female reproductive system cancers, respiratory system cancers, and urinary system cancers. Conclusion: This study demonstrated that HOXD-AS1 was closely correlated with tumor size, lymph node metastasis, distant metastasis, and TNM stage, and an increased HOXD-AS1 expression could be a reliable prognostic biomarker in human cancers. However, more studies are needed to confirm this conclusion. [ABSTRACT FROM AUTHOR]

Abstract: A conductive layer, made of multiwalled carbon nanotubes (MWCNTs), with micro‐cracks and a micro/nanoporous structure is fabricated between an active material layer (AML) and a current collector. The coating thickness of the MWCNT‐based conductive layer (MCL) varies in the range of 25–100 μm. Electrochemical tests of half‐cells demonstrate that both the mesocarbon‐microbeads (MCMB) anode and the LiCoO2 cathode with a micro‐cracked MCL show higher capacity, lower impedance, and less capacity fading than the pristine and non‐cracked electrodes. These improvements are caused by the enhancement of adhesion strength and the buffer effect of the micro‐cracked MCL. With a change of the coating thickness, the size and number of micro‐cracks on the MCL varies to accommodate the active material with different particle sizes. The electrodes with a micro‐cracked MCL with a coating thickness of 50 and 75 μm are suitable for MCMB and LiCoO2 with a particle size of 10–20 μm. [ABSTRACT FROM AUTHOR]

Rectangular caverns are increasingly used in underground engineering projects, the failure mechanism of rectangular cavern wall rock is significantly different as a result of the cross-sectional shape and variations in wall stress distributions. However, the conventional computational method always results in a long-winded computational process and multiple displacement solutions of internal rectangular wall rock. This paper uses a Laurent series complex method to obtain a mapping function expression based on complex variable function theory and conformal transformation. This method is combined with the Schwarz-Christoffel method to calculate the mapping function coefficient and to determine the rectangular cavern wall rock deformation. With regard to the inverse mapping concept, the mapping relation between the polar coordinate system within plane ς and a corresponding unique plane coordinate point inside the cavern wall rock is discussed. The disadvantage of multiple solutions when mapping from the plane to the polar coordinate system is addressed. This theoretical formula is used to calculate wall rock boundary deformation and displacement field nephograms inside the wall rock for a given cavern height and width. A comparison with ANSYS numerical software results suggests that the theoretical solution and numerical solution exhibit identical trends, thereby demonstrating the method’s validity. This method greatly improves the computing accuracy and reduces the difficulty in solving for cavern boundary and internal wall rock displacements. The proposed method provides a theoretical guide for controlling cavern wall rock deformation failure. [ABSTRACT FROM AUTHOR]

The article presents a study on a field test and analytical analysis for measurements of vertical pressure at a top coal mining face at Datong Tashan Mines, China. Based on the real-time pressure monitoring of single props and hydraulic supports at a top coal mining face, intensive factors of pressure were adopted to provide a quantitative description of the mining mechanics.

Thermosensitive poly(NIPAAm-co-AMPS) hydrogels were prepared by copolymerization of N-isopropyl acrylamide (NIPAAm) and 2-acrylamido-2-methyl 1-propansulfonic acid (AMPS) by employing N, N′-methylenebis(acrylamide) (BIS) as cross-linker. Uniformly distributed silver nanoparticles (Ag-NP) were obtained within hydrogel networks as nanoreactors via in situ reduction of silver nitrate (AgNO) using sodium borohydride (NaBH) as reducing agent. The catalytic properties of Ag-NP-poly(NIPAAm-co-AMPS) hydrogels presented obvious temperature dependence upon the reduction of 4-nitrophenol (4-NP) in aqueous solution. Interestingly, the addition of α-cyclodextrin (α-CD) could further enhance the reduction rate and change the associated activation parameters. This advanced catalytic system with temperature dependence and α-CD synergetic effect presented promising applications in catalytic chemistry. [ABSTRACT FROM AUTHOR]

Roof-coal recovery rate and the performance of gas extraction are essentially controlled by the fractures within coal-rock mass. Thus, it is important to generate the accurate fracture network ahead of mining face. In this study, ten boreholes located differently from the 8212 working face of Tashan Mine in Datong coal mining group, China, were drilled. With the help of borehole video instruments, the location, orientation of each fracture and the fracture number of different intersection type on each borehole wall were mapped with the advancing of mining face. These data were analyzed using the Matlab Toolbox RJNS and Dips to determine structural homogeneity zone, to find the number of fracture sets that exist in the coal-rock mass, volume density frequency for each set and the probability distributions of orientation, fracture size in 3-D. Sampling biases associated with orientation, spacing were corrected during the process. The constructed fracture networks were validated by comparing the observed mean spacing along normal vector of mean orientation for each set and the predict value on similar scanlines. [ABSTRACT FROM AUTHOR]

With the development of GEN-IV nuclear reactor technology, the supercritical carbon dioxide (SCO2) Brayton cycle has attracted wide attention for its simple structure and high efficiency. Correspondingly, a series of research has been carried out to study the characteristics of the cycle. The control flexibility of the power generation system has rarely been studied. This paper carried out a dynamic performance of the 20 MW-SCO2 recompression cycle based on the Simulink software. In the simulation, the response characteristics of the system main parameters under the disturbances of cooling water temperature, split ratio, main compressor inlet temperature and pressure were analyzed. The results show that the turbine inlet temperature is most affected by the disturbances, with a re-stabilization time of 2500–3000 s. According to the response characteristics of the system after being disturbed, this study proposed a stable operation control scheme. The scheme is coordinated with the main compressor inlet temperature and pressure control, recompressor outlet pressure control, turbine inlet temperature control and turbine load control. Finally, the control strategy is verified with the disturbance of reduced split ratio, and the results show that the control effect is good. [ABSTRACT FROM AUTHOR]

The decomposition of the Nd-Ce-Fe-B phase to form CeFe2 has been usually believed to have an important positive effect on the magnetic properties of Nd-Ce-Fe-B permanent magnetic materials. In this work, a new decomposition process of the Nd-Ce-Fe-B phase on the formation of the CeFe2 phase was observed to play a negative role in its magnetic properties. It is demonstrated that the Nd-Ce-Fe-B phase decomposes into non-magnetic CeFe2, accompanied by the precipitation of Fe soft-phase. The kinks usually occurring in the demagnetization curves of Ce-rich Nd-Ce-Fe-B magnets have been determined to be related to the Fe soft-phase. Instead of using CeFe2 as a grain-boundary phase, another Ce-Cu boundary phase has been explored to efficiently improve the coercivity of Ce-rich Nd-Ce-Fe-B magnets, provided that the Ce-Cu boundary phase has an appropriate Ce to Cu ratio. The present results contribute to the mechanism comprehension and high-performance design of Nd-Ce-Fe-B permanent magnetic materials. [ABSTRACT FROM AUTHOR]

Wetland rehabilitation, highlighted in the United Nations (UN) Sustainable Development Goals (SDGs), is imperative for responding to decreased regional biodiversity and degraded ecosystem functions and services. Knowing where the most suitable wetland rehabilitation areas are can strengthen scientific planning and decision-making for natural wetland conservation and management implementation. Therefore, we integrated multisource geospatial data characterizing hydrological, topographical, management, and policy factors, including maximum surface water coverage, farming time, anthropogenic disturbance, and wetland protection level, to identify potential wetland rehabilitation areas in the Sanjiang Plain (SJP), the largest marsh distribution and a hotspot wetland loss region in China. Our results indicate that a total of 11,643 km2 of wetlands were converted into croplands for agricultural production from 1990 to 2018. We estimated that 5415 km2 of the croplands were suitable for wetland rehabilitation in the SJP, of which 4193 km2 (77%) have high rehabilitation priority. Specifically, 63% of the potential areas available for wetland rehabilitation are dry croplands (3419 km2), the rest (37%) being paddy fields. We argue that the selected indicators and approach used in this study to determine potential wetland rehabilitation areas could guide their investigation, at either the provincial or national scale and would be beneficial to conservation and sustainable management of wetlands in the SJP. [ABSTRACT FROM AUTHOR]

The interface design between the current collector and active materials has a non‐negligible effect on the performance of lithium‐ion batteries (LIBs). Inspired by the honeycomb with a large specific surface area, this work validates the use of a surface‐patterned cellular Cu@CuO composite current collector with a hexagonal blind hole array and a nanostructured film of CuO nanoflowers for LIBs. This unique structure is synthesized by lithography and solution immersion. Mesocarbon microbead graphite powders are used as the active materials. Results show that the battery with the cellular Cu@CuO current collector maintains a reversible charge capacity of 354.1 mAh g−1 at 100 mA g−1 after 200 cycles. Compared with the Cu‐based current collector with a hexagonal blind hole array and a bare Cu current collector, the new pattern gains a performance improvement in the reversible capacity by 27.9% and 153.2%, respectively. The excellent electrochemical property of the cellular Cu@CuO current collector can be ascribed to strengthened adhesion with the active materials, reduced contact resistance, and improved Li‐ion diffusion capability. Due to the enhanced electrochemical performance, facile preparation processes, and cost‐effective raw materials, the new current collector shows great potential to replace the conventional current collector of energy storage systems. [ABSTRACT FROM AUTHOR]