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The compaction quality of embankment dams directly affects the safe operation of power stations. The traditional monitoring method has the shortcomings of limited sample and time consumption. Compaction quality can be reflected by the compression ratio (CR) of the filling material. A novel method based on unmanned aerial vehicle (UAV) photogrammetry technology, which can rapidly acquire the CR of the entire filling area, is proposed in the present paper. Specifically, the CR nephogram is obtained by processing the terra information of the compaction body collected by the UAV. Validation of the CR results is performed by comparing them with the results obtained via leveling measurements. Mean absolute error between CR results and leveling measurements results is less than 1%, and the corresponding settlement value error is millimeter-level, reflecting a fairly good agreement. Furthermore, the reduced-scale experiment shows that the UAV-based CR method is more stable than manual measurements, and the efficiency is increased by more than five times, which meets the requirements of compaction quality monitoring and quality control. The CR nephogram obtained can reflect the compaction quality information rapidly, comprehensively, and accurately, thereby guiding the quality control of embankment dam construction.

The rebound index C r is an important design parameter in engineering construction, and its determination is cumbersome and susceptible to errors. Explaining the macroscopic rebound characteristic parameter C r from the perspective of microscopic mechanism is an important research area that is addressed in this study. In this paper, the different soil parameters, including the C r parameter and the physical parameters (void ratio e r liquid limit water content W L , and plasticity index I p ), have been determined through experiments for the undisturbed clay of Chongming East Shoal (CES), Shanghai. Further, scanning electron microscopy (SEM) imaging was used to analyze the microstructural features. Through SEM, the grey correlation degree, the average abundance of structural units AC p and the average equivalent diameter of pores AD v were determined as the soil microstructure parameters with the most significant correlation with C r . The predictive analysis model of C r was then carried out combined with the PSO-SVM algorithm. In order to evaluate the influence of microscopic parameters of soil on the prediction accuracy, four sets of input parameter combinations were used. The results indicate the high prediction accuracy of the developed model. Sensitivity analysis was also carried out, which showed that the sensitivity of C r to AC p and AD v was significantly lower than e ; however, the difference from w L and I p was small, indicating that it is imperative to consider microscopic parameters while predicting C r . This study, thus, provides a basis and method for predicting the rebound index of soil from the microstructure perspective.

The existence of faults in the dam site area threatens the stability and safety of large-scale hydropower projects in China. The fault argillaceous zone is the worst kind of fault fracture zone, and the determination of its deformation and strength parameters is the key point of rock engineering investigation. In this study, the in-situ bearing plate test and direct shear test were carried out on the gouge zone of F67 fault in the dam site of Fengman Hydropower Station. The test results show that the deformation and shear law of each test point is good, which is basically consistent with the actual condition of the measured rock mass. However, due to the limited number of measurements, the results are limited in terms of macroscopic representation. The experimental results provide scientific basis for subsequent engineering design and further enhance the understanding of mechanical properties of fault gouges.

For deep and large foundations, the soil below the foundation is often in a compensated or overcompensated state after the structure is completed. At this time, the proportion of recompression settlement to the total settlement is more significant. Attention should be paid to calculating the rebound deformation and recompression deformation of foundation pit excavation. In this work, the silty clay, clay, and silt in the Binhai New Area of Tianjin were studied. Oedometer tests were carried out on original and remolded samples to investigate the compressibility of different soil samples under unloading/reloading (the minimum unloading pressure (Pmin) was set to 50, 100, 200, and 400 kPa, and the maximum preloading pressure (Pmax) was kept at 400, 800, 1200, and 1600 kPa, respectively). The results indicate that the difference between the compressibility of the original and remolded samples decreases with repeated loading. It is also observed that the smaller the Pmin value, the smaller the corresponding difference. Compared with the remolded sample, the original sample has a higher maximum rebound rate (δmax) and lower recompression rate (λ). When Pmin is constant, the original and remolded samples show that δmax increases while λ decreases with the increase of Pmax, eventually becoming the same. Clay is the least sensitive to δmax and the most sensitive to λ. Combined with the analysis of pore distribution characteristics, the results indicate that the medium pores converge to the small pores during compression. The conclusion of this study can provide a theoretical basis and support for the design of underground space in coastal areas as well as for deep and large foundation buildings according to deformation control design.

Sympathetic neural remodeling, which involves the inflammatory response, plays an important role in ventricular arrhythmias (VAs) after myocardial infarction (MI). Adrenergic receptors on macrophages potentially modulate the inflammatory response. We hypothesized that the increased level of catecholamines activates macrophages and regulates sympathetic neural remodeling after MI. We treated MI mice with either clodronate or metoprolol for 5 days following coronary artery ligation. Mice without treatment after MI and sham-operation mice served as the positive control and negative control, respectively. The norepinephrine levels in plasma and the peri-infarct myocardium increased by almost two-fold in the MI mice compared with the sham-operation mice. Both in vivo and ex vivo electrophysiology examinations showed that the vulnerability to VAs induced by MI was alleviated by macrophage depletion with clodronate and β1-adrenergic blockade with metoprolol, which was in line with circulating and peri-infarct norepinephrine levels, sympathetic reinnervation, and the expression of nerve growth factor (NGF) 7 days after surgery. To further verify the interaction between catecholamines and macrophages, we preconditioned lipopolysaccharide-stimulated RAW 264.7 cells using epinephrine or epinephrine with selective adrenergic antagonists. The expression and release of inflammatory factors including NGF were enhanced by epinephrine. This effect was inhibited by metoprolol but not by other subtype antagonists. Our data suggested that the increased level of catecholamines, traditionally known as positive inotropes secreted from sympathetic nerve endings, might regulate cardiac sympathetic neural remodeling through β1-adrenergic receptors on macrophages, subsequently inducing VAs after MI.

The use of spectral features to estimate leaf area index (LAI) is generally considered a challenging task for hyperspectral data. In this study, the hyperspectral reflectance of winter wheat was selected to optimize the selection of spectral features and to evaluate their performance in modeling LAI at various growth stages during 2008 and 2009. We extracted hyperspectral features using different techniques, including reflectance spectra and first derivative spectra, absorption and reflectance position and vegetation indices. In order to find the best subset of features with the best predictive accuracy, partial least squares regression (PLSR) and variable importance in projection (VIP) were applied to estimated LAI values. The results indicated that the red edge–NIR spectral region (680 nm–1300 nm) was the most sensitive to LAI. Most features in this region exhibited a high correlation with LAI and had higher VIP values, especially the first derivative waveband at 750 nm (r = 0.900, VIP = 1.144). Adding a large number of features would not significantly improve the accuracy of the PLSR model. The PLSR model based on the fourteen features with the highest VIP values predicted LAI with a mean bootstrapped R2 value of 0.880 and a mean RMSE of 0.943 on the validation dataset and produced an estimated LAI result better than that, including the entire 54-feature dataset with a mean R2 of 0.875 and a mean RMSE of 0.965. The results of this study thus suggest that the use of only a few of the best features by VIP values is sufficient for LAI estimation.

Corncob is a potential feedstock for biorefineries to produce cellulosic ethanol and other chemicals. Densifying lignocellulosic biomass with chemicals followed by autoclave (DLCA) has been confirmed an efficient and economical pretreatment method, and it was applied in the present work for conversion of corncob to bioethanol. The dosage of sulfuric acid, solid loading of biomass, and autoclave time for pretreatment were investigated. Enzymatic hydrolysis at 25–35% solids loadings resulted in 91–97% sugar conversions. Fermentation of the resulted hydrolysates went well with the highest ethanol titer reaching 75.71 g/L at 35% solid loading. Simultaneous saccharification and co-fermentation was applied to further improve xylose consumption at high solids loadings and the ethanol titer was enhanced to 82.0 g/L at 35% solid loading with an ethanol yield of 21.67 kg/100 kg corncob. This study demonstrated DLCA provided a highly digestible and highly fermentable corncob for biorefinery.

MoS 2 hollow spheres were controllably synthesized with the assistance of surfactant [polyvinyl pyrrolidone (PVP)] through a facile hydrothermal method. Our moderate synthetic route also yielded a large quantity MoS 2 nanospheres and nanosheets by adjusting the additive concentration of PVP. The MoS 2 nanosheets were synthesized without the addition of PVP. With the gradual increase of additive concentration of PVP, the MoS 2 nanosheets assembled into MoS 2 nanospheres and the MoS 2 nanospheres further assembled into the MoS 2 hollow spheres. Meanwhile, a reasonable growth mechanism related to the formation of MoS 2 structures was proposed preliminarily. Moreover, the light absorption and photocatalytic properties of synthesized MoS 2 structures were investigated. The results indicated that MoS 2 hollow spheres exhibited excellent photocatalytic properties, which could be attributed to the unique structure feature, distribution characteristic, abundant of photoactive sites. Thus, it indicated for a huge potential for application in photocatalytic materials, which could solve the water pollution all around the world.

Lili Tian,1 Xinchuan Wei,2 Rong Cao,3 Yong Tang,4 Lili Liang,5 Fei Jia,6 Lina Yang,7 Nijuan Li,4 Jing Xu,3 Yu Wang,1 Bo Liu,6 Xia Li,8 Min Xie1 1Department of Anaesthesiology, Sichuan Provincial People’s Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, People’s Republic of China; 2Department of Anaesthesiology, West China Second University Hospital, Sichuan University, Chengdu, People’s Republic of China; 3Department of Anaesthesiology, Chengdu Women’s and Children’s Central Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, People’s Republic of China; 4Department of Anaesthesiology, Sichuan Jinxin Xinan Women & Children Hospital, Chengdu, People’s Republic of China; 5Department of Obstetrics and Gynaecology, Sichuan Provincial People’s Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, People’s Republic of China; 6Department of Anaesthesiology, Chengdu Jinjiang District Women & Children Health Hospital, Chengdu, People’s Republic of China; 7Department of Operating Room Nursing, Sichuan Provincial People’s Hospital, School of Medicine, University of Electronic Science and Technology of China, Chengdu, People’s Republic of China; 8Department of Anaesthesiology, West China Hospital, Sichuan University, Chengdu, People’s Republic of ChinaCorrespondence: Min Xie, Email 1239473792@qq.com Xia Li, Email 1129144272@qq.comBackground: Epidural anaesthesia is commonly utilized for pain relief during labour. However, it has been observed that this method can lead to maternal fever (temperature≥ 38 °C). The mechanism of epidural-related maternal fever (ERMF) remains unclear. This study aims to explore the correlation between the level of sensory blockade and the occurrence of ERMF.Methods: This cohort study included primigravid women who received patient-controlled epidural analgesia (PCEA). We employed a wireless continuous temperature-monitoring device to capture minute-by-minute fluctuations in maternal temperature. Additionally, various indicators pertaining to the mother, neonate, and anaesthesia were recorded throughout the labour process. Receiver operating characteristic curves were used to evaluate the predictive performances of the sensory block level and duration of block level for fever. Logistic regression was used for multifactorial analyses. Propensity score matching was employed to eliminate endogeneity and control confounding factors.Results: The study included a sample of 953 primigravid women, among whom an average of 29.8% (284/953) experienced intrapartum fever. The highest level of sensory block was significantly higher in febrile women than in nonfebrile women. Women with labour analgesia may be more prone to fever when the duration of block level above innervation level of thoracic 8 was longer than 135 minutes. Factors influencing ERMF include the highest level of sensory blockade, duration of block level (above T8), and the meconium-stained amniotic fluid (MSAF).Conclusion: During epidural labour analgesia, the highest level of sensory block was significantly higher in febrile women than in nonfebrile women. When the maternal sensory block plane surpasses the innervation level of thoracic 8 and persists for longer than 135 minutes, the likelihood of maternal fever increased. Therefore, maintaining the maternal sensory block plane below T8 may reduce fever.Keywords: epidural-related maternal fever, patient-controlled epidural analgesia, sensory block level

ZnO/Mn hierarchical structures have been synthesized by a facile one-step solution route at room temperature and their structure, morphology, photoluminescence, and photocatalytic activity fully investigated. Reduced crystallite size and increased microstrain of ZnO were found on incorporation of Mn ions. Room-temperature photoluminescence spectra of the as-synthesized ZnO/Mn hierarchical structures presented violet and blue emission. Meanwhile, ZnO/Mn hierarchical structures exhibited enhanced photocatalytic activity compared with pristine ZnO. Optimal content (5%) of Mn ions in the ZnO matrix will lead to the highest photodegradation efficiency.