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The research work aimed at identifying the failure mode and energy evolution of damaged granite by uniaxial compression tests. The predamage specimens were prepared by cyclic loading with high confining pressure under constant upper and lower cyclic limit loading, which were collected from China. The test results showed that the cyclic loading with high confining pressure does damage to the rock to a certain degree. The macrocracks of predamage rock appear initially when the uniaxial compressive stress reaches 0.8 σmax. The failure mode is mainly mixed by shear failure and tensile failure. There is a critical state of the cyclic test that the predamage rock transforms the brittle deformation into a ductile one during the triaxial compression loading. Before the critical state, the average deformation energy of predamage rock is impacted by confining pressure (strongly, linear negative). The impact energy index and the residual energy of the predamage rock gradually decrease linearly with the increase of confining pressure. [ABSTRACT FROM AUTHOR]

The utilization of industrial solid waste in mines is an important approach to resource utilization. The backfill material in mines is mainly composed of solid waste, which plays a supporting role. The excitation effect of lime on phosphogypsum and fly ash in backfill was studied in this paper. The macroscopic and microscopic characteristics of the backfill material were tested using uniaxial compression, nuclear magnetic resonance, scanning electron microscopy, and electrochemical techniques, and a relationship model was established between them. Furthermore, the influence of industrial solid waste on the properties of the backfill material under the action of lime and the hydration mechanism between different industrial solid wastes were studied. The results show that (1) under the action of lime, fly ash reacts with lime to produce C-S-H and C-A-H, and then C-A-H reacts with phosphogypsum to produce AFt. (2) The excess phosphogypsum also fills the pores. Therefore, 1.8% lime reduces the porosity of the backfill by 17.88% and increases the strength by 21.57%. (3) The cross-scale relationship shows that strength is inversely proportional to each type of pore content and fractal dimension, and it logarithmically increases with impedance at different frequencies. The lower the frequency, the stronger the relationship is. (4) This study indicates that industrial solid waste is a suitable cement replacement. [ABSTRACT FROM AUTHOR]

Introduction: Aims of the study were to assess the differences in the diagnostic efficacy of 68Ga-somatostatin receptor analogs (68Ga-SSAs) and 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) for detecting bone metastases in neuroendocrine neoplasm (NEN) and to analyze the correlation between imaging features and clinical features of BMs. Methods: We retrospectively analyzed the clinical and imaging data of 213 NEN patients who underwent 68Ga-SSA PET/CT and were finally diagnosed as BMs by pathology or follow-up. Of those, 103 patients underwent 18F-FDG PET/CT within 7 days after 68Ga-SSA PET/CT. Result: The BM detection rate of 68Ga-SSA PET/CT was higher than 18F-FDG PET/CT (86.4% vs. 66.0%, p = 0.02) in 103 patients with dual scanning. Meanwhile, the number of positive lesions in 68Ga-SSA PET/CT was significantly more than in 18F-FDG PET/CT (3.37 ± 1.95 vs. 2.23 ± 2.16, t = 4.137, p < 0.001). Most bone metastasis lesions presented as osteogenic change in CT (55.4%, 118/213). Concerning the primary tumor, the most frequent were of pancreatic origin (26.3%, 56/213), followed by rectal origin (22.5%, 48/213), thymic origin in 33 cases (15.5%), pulmonary origin in 29 cases (13.6%), paraganglioma in 20 cases (9.4%). The efficiency of 68Ga-SSA PET/CT to detect BMs was significantly correlated with the primary site (p = 0.02), with thymic carcinoid BMs being the most difficult to detect, and the positive rate was only 60.6% (20/33). However, 18F-FDG PET/CT positive rate was 76.92% (10/13) in thymic carcinoid BMs. In addition, the BMs of 7 patients in this study were detected by 68Ga-SSA PET earlier than CT for 4.57 months (range: 2–10 months). Conclusion:68Ga-SSA PET/CT has higher sensitivity for detecting the BMs of NEN than 18F-FDG and detects the BM earlier than CT. Moreover, 18F-FDG PET/CT should be a complement for diagnosing the BMs of thymic carcinoids. [ABSTRACT FROM AUTHOR]

The alteration of land use and cover (LULC) and the landscape ecological risk index (LERI) significantly impact carbon storage. Examining the carbon storage services in ecologically significant places is crucial for achieving a harmonious relationship between economic development in the region, conservation of terrestrial ecosystems, and mitigation of carbon sink depletion. This study aims to provide a complete framework that integrates the PLUS, Fragstats, and InVEST models. This framework will be utilized to optimize LULC and LERI, specifically maximizing carbon storage. The analysis will be carried out over an extended duration and from various viewpoints. The results indicate that the MJRB ecosystem experienced three clearly defined phases: enhancement (1985–1995), degradation (1995–2010), and subsequent enhancement (2010–2020). The LERI of high-level and carbon storage patterns showed similar trends. The degradation of local terrestrial ecosystems can primarily be due to the widespread use of ecological land caused by socio-economic development. The Ecological Preservation Scenario is projected to increase 41.97 Tg and 115.18 Tg in carbon storage. In contrast, the urban development scenario showed a substantial decrease in carbon storage rates, namely 0.89% and 1.34%, primarily evident in the Chengdu urban zone. An analysis of coupling coordination revealed a negative relationship between carbon storage and high LERI, while a positive connection was observed with low LERI. This study established a framework for rapidly assessing and forecasting the trajectory of carbon storage. It aids in optimizing land use patterns, conserving areas with high carbon sequestration, and ensuring the establishment of high-quality ecosystems. This study serves as a guide for achieving regional "dual carbon" objectives. [ABSTRACT FROM AUTHOR]

Blast-induced ground vibration is the key negative effect of blasting, so its prediction and control are of great engineering value. With this aim, this study uses support vector regression (SVR) and gaussian process regression (GPR) as prediction tools, and four optimization algorithms, namely, the chameleon swarm algorithm (CSA), marine predators algorithm (MPA), young's double-slit experiment optimizer algorithm (YDSE), and exponential distribution optimizer algorithm (EDO) are used to optimize the hyperparameters, to establish eight prediction models for predicting blast-induced ground vibration. Moreover, the 0-fold cross-validation method was applied to avoid overfitting and underfitting in the model training process. This study used a variety of evaluation indicators to quantitatively evaluate the eight prediction models developed. The prediction results show that CSA-GPR, MPA-GPR, YDSE-GPR, and EDO-GPR have the same prediction results, and their relative errors are less than 5%. The evaluation results show that MPA and YDSE have better optimization finding ability than CSA and EDO, and GPR has a more significant advantage than SVR in predicting such kind ground vibration. [ABSTRACT FROM AUTHOR]

Objective To establish a differential model of phlegm and blood stasis pattern and qi deficiency and blood stasis pattern in stable angina pectoris using radiomics. Methods A total of 91 patients with stable angina pectoris who underwent coronary artery CT angiography in Affiliated Hospital of Liaoning University of Traditional Chinese Medicine from January 2021 to January 2022 were collected, including 47 cases of phlegm and blood stasis pattern and 44 cases of qi deficiency and blood stasis pattern. The patients were divided into train set(64 cases) and test set(27 cases) according to the ratio of 7:3 by stratified random sampling method. 3D-slicer software was used to extract the radiomics features of pericoronary adipose tissue(PCAT) images. Principal component analysis was used to visualize the distribution of radiomics features of pattern of phlegm and blood stasis and pattern of qi deficiency and blood stasis. The least absolute shrinkage and selection operator regression analysis and support vector machine decreasing feature elimination were used for feature selection. The multinomial logistics regression was used for model construction. The receiver operating characteristic (ROC) curve was used to verify the model in the train set and the test set to evaluate the effectiveness of the radiomics features in differentiating phlegm and blood stasis pattern and qi deficiency and blood stasis pattern. Finally, Spearman coefficient was used to analyze the correlation between the differential features and clinical physicochemical data. Results A total of 837 radiomics features were extracted from PCAT images by 3D-slicer software. In the principal component analysis, PC1 and PC2 explained 77.9% and 8.1% of the total variance, respectively, and there was a relatively obvious separation trend between the two pattern groups. After feature screening, 7 radiomics features were used to construct the differential model of phlegm and blood stasis pattern and qi deficiency and blood stasis pattern. The area under the ROC curve (AUC) of the differential model was 0.844 in the train set and 0.834 in the test set. Spearman correlation analysis showed that the differential features were significantly correlated with cTnI, neutrophil, triglyceride, total cholesterol, and leukocyte. Conclusion The CT radiomics model based on PCAT has a high discrimination efficiency for stable angina pectoris with phlegm and blood stasis pattern and qi deficiency and blood stasis pattern. [ABSTRACT FROM AUTHOR]

Nighttime light remote sensing images show significant application potential in marine ship monitoring, but in areas where ships are densely distributed, the detection accuracy of the current methods is still limited. This article considered the LJ1-01 data as an example, compared with the National Polar-orbiting Partnership (NPP)/Visible Infrared Imaging Radiometer Suite (VIIRS) data, and explored the application of high-resolution nighttime light images in marine ship detection. The radiation values of the aforementioned two images were corrected to achieve consistency, and the interference light sources of the ship light were filtered. Then, when the threshold segmentation and two-parameter constant false alarm rate methods are combined, the ships’ location information was with obtained, and the reliability of the results was analyzed. The results show that the LJ1-01 data can not only record more potential ship light but also distinguish the ship light and background noise in the data. The detection accuracy of the LJ1-01 data in both ship detection methods is significantly higher than that of the NPP/VIIRS data. This study analyzes the characteristics, performance, and application potential of the high-resolution nighttime light data in the detection of marine vessels. The relevant results can provide a reference for the high-precision monitoring of nighttime marine ships.

The viscosity within cells is a crucial microenvironmental factor, and sulfur dioxide (SO2) has essential functions in regulating cellular apoptosis and inflammation. Some evidence has been confirmed that changes in viscosity and overexposure of SO2 within the cell may cause detrimental effects including, but not limited to, respiratory and cardiovascular illnesses, inflammation, fatty liver, and various types of cancer. Therefore, precise monitoring of SO2 and viscosity in biological entities holds immense practical importance. Therefore, in this research, we developed a versatile fluorescent TCF‐Cou that enables the dual detection of SO2 and viscosity in the living system. Probe TCF‐Cou possessed a response to viscosity and SO2 through red and green emissions. The alteration of SO2 and viscosity levels in live cells and zebrafish were also monitored using probe TCF‐Cou. We hope that this fluorescent probe could be a potential tool for revealing the related pathological and physiological processes through monitoring the changes in SO2 and viscosity. [ABSTRACT FROM AUTHOR]

Air-entraining agents have the function of optimizing pores and improving the performance of backfill. In this study, we used tailings and cement as the main raw materials and added different amounts of air-entraining agents to make backfill samples. By testing the uniaxial compressive strength (UCS) and microstructure, macro- and micro characteristics were studied. Nuclear magnetic resonance technology was used to explore pore characteristics, and fractal theory was used to quantitatively discuss the complexity of pore structure. Finally, a cross-scale relationship model between UCS and pores was established. The main conclusions are as follows: (1) Adding the appropriate amount of air-entraining agents can optimize pore structure and increase the UCS of backfill materials, which is beneficial to backfill materials. (2) The pores of backfill materials have fractal characteristics, the fractal effects of pores with different pore size ranges are different, and the air-entraining agent has a certain influence on the fractal characteristics of the pores. (3) There are inverse relationships between UCS and different pore size ranges. [ABSTRACT FROM AUTHOR]