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Snow plays a crucial role in global climate regulation, hydrological processes, and environmental change, making the accurate acquisition of snow depth data highly significant. In this study, we used Sentinel-1 radar data and employed a simulated annealing algorithm to select the optimal influencing factors from radar backscatter characteristics and spatiotemporal geographical parameters within the study area. Snow depth retrieval was subsequently performed using both random forest (RF) and Support Vector Machine (SVM) models. The retrieval results were validated against in situ measurements and compared with the long-term daily snow depth dataset of China for the period 2017–2019. The results indicate that the RF model achieves better agreement with the measured data than existing snow depth products. Specifically, in the Xinjiang region, the RF model demonstrates superior performance, with an R2 of 0.92, a root mean square error (RMSE) of 2.61 cm, and a mean absolute error (MAE) of 1.42 cm. In contrast, the SVM regression model shows weaker agreement with the observations, with an R2 lower than that of the existing snow depth product (0.51) in Xinjiang, and it performs poorly in other regions as well. Overall, the SVM model exhibits deficiencies in both predictive accuracy and spatial stability. This study provides a valuable reference for snow depth retrieval research based on active microwave remote sensing techniques.

The caisson method is typically employed in foundation pit projects characterized by complex surrounding structures and challenging engineering geological conditions. The sinking process involves complex soil-structure interactions, particularly the sidewall friction between the caisson and the surrounding soil strata. This friction is a critical factor, as it not only determines the feasibility and safety of the sinking operation but also influences the pattern and magnitude of surrounding ground subsidence. This study aims to explore the mechanism of sidewall friction between the caisson and strata and its direct impact on controlling the sinking process and mitigating surrounding subsidence. The analysis is based on the large caisson engineering of Zhuchong Pump Station, located in Xinyang City behind the Chushandian reservoir. By conducting a numerical simulation of the sinking process and analyzing measured data from on-site subsidence monitoring points, this research reveals that the caisson induces a parabolic-shaped subsidence curve in the surrounding ground surface. The magnitude and extent of ground subsidence around the caisson increase with greater sinking depth and with proximity decreasing distance from the sidewall. The study further demonstrates that sidewall friction significantly influences ground subsidence. Specifically, lower friction in the initial sinking phase results in noticeable ground uplift due to reduced constraint on soil displacement. Conversely, higher friction leads to increased ground subsidence as the sinking depth progresses. The study reveals that the influence pattern of friction between the caisson sidewall and the surrounding soil on ground surface subsidence, and lower friction would result in pronounced ground uplift due to reduced constraint on surface displacement during the initial sinking phase, and higher friction would increase ground subsidence as the caisson sinking depth increases. The findings of this research may help provide a technical reference for subsidence control in similar large-scale caisson projects.

Post-ERCP pancreatitis (PEP) is a type of acute pancreatitis (AP) and the most common complication after ERCP. NLRP3 inflammasome-dependent pyroptosis is a key factor in the pathogenesis of acute pancreatitis. Gegen Qinglian decoction (GQD) is a traditional Chinese medicine formula that has the effects of clearing heat and detoxifying, and is now widely used in pancreatic diseases. We have clinically found that GQD can effectively prevent PEP. To explore its potential preventive mechanism, we conducted rat experiments. Before modeling, GQD, indomethacin suppository, NLRP3 inhibitor, etc. were used for intervention, and the GQD used was qualitatively analyzed by UPLC-QTOF-MS/MS. Then, a PEP model was established by injecting contrast medium into the pancreatic and bile ducts of rats, an model was made by intervening with sodium taurocholate (STC) in AR42J cells. The severity of pancreatitis and the levels of NLRP3 inflammasome components were subsequently evaluated and . UPLC analysis of GQD identified 227 known metabolites. The expression of NLRP3, Caspase-1, and GSDMD in PEP model was significantly increased compared to the blank group, indicating the activation of NLRP3 inflammasome mediated cell pyroptosis during PEP occurrence. Prophylactic administration of GQD resulted in a reduction in the expression of NLRP3, Caspase-1, and GSDMD. Additionally, GQD significantly alleviated the pathological inflammation in the pancreas, and reduced levels of amylase and inflammatory cytokines. The GQD group, indomethacin suppository group, NLRP3 inhibitor group, and siRNA gene suppression group showed similar results. GQD can effectively prevent PEP, and its primary mechanism may be related to the regulation of NLRP3 inflammasome-mediated pyroptosis. Provide theoretical basis for the use of traditional Chinese medicine in clinical practice to prevent diseases.

Snow water equivalent (SWE) is a key parameter in the Earth’s energy budget and water cycle. It has been demonstrated that SWE can be retrieved using active microwave remote sensing from space. This necessitates the development of forward models that are capable of simulating the interactions of microwaves and the snow medium. Several proposed models have described snow as a collection of sphere- or ellipsoid-shaped ice particles embedded in air, while the microstructure of snow is, in reality, more complex. Natural snow usually forms a sintered structure following mechanical and thermal metamorphism processes. In this research, the bi-continuous vector radiative transfer (bi-continuous-VRT) model, which firstly constructs snow microstructure more similar to real snow and then simulates the snow backscattering signal, is used as the forward model for SWE estimation. Based on this forward model, a parameterization scheme of snow volume backscattering is proposed. A relationship between snow optical thickness and single scattering albedo at X and Ku bands is established by analyzing the database generated from the bi-continuous-VRT model. A cost function with constraints is used to solve effective albedo and optical thickness, while the absorption part of optical thickness is obtained from these two parameters. SWE is estimated after a correction for physical temperature. The estimated SWE is correlated with the measured SWE with an acceptable accuracy. Validation against two-year measurements, using the SnowScat instrument from the Nordic Snow Radar Experiment (NoSREx), shows that the estimated SWE using the presented algorithm has a root mean square error (RMSE) of 16.59 mm for the winter of 2009–2010 and 19.70 mm for the winter of 2010–2011.

Low-angle lee-side slopes of dunes are commonly developed on the world’s riverbeds, and dune migration associated with sediment transport exert a major influence on riverine processes. However, the catenary-bead dune has been identified in the Yangtze River (YR) Estuary, featuring a higher lee-side angle. To date, the morphological variation and formation reasons of catenary-bead dunes in the YR Estuary remain uncharacterized. In this study, we used a multibeam echo system (MBES) to investigate the bedforms of the YR estuary during 2014–2015, as well as to discuss the seasonal variation of catenary-bead dunes. The results indicate that the catenary-bead dunes of the YR Estuary are characterized by growth during the flood season and extinction during the dry season. The lee-side angle is typically ~16.7°, which is larger than that of other dune types (3.7–8°) in the estuary; moreover, the catenary-bead dunes are higher than other dune types of the same length in the YR Estuary. The relationship between the dune height (H) and length (L) was found to be H = 0.1667L0.603 (R2 = 0.38), while the other dune types yielded the relationship of H = 0.0845L0.758 (R2 = 0.52). Strong runoff superimposing the ebb tide led to the development of catenary-bead dunes. Furthermore, the higher coarse sediment content (69.9–72%) and lower clay content (6.3–6.7%) of the riverbed sediment are favorable for their formation, while the higher curved crest-lines are favorable for the formation of the associated elliptical pits.

Background/Aims: The embryonic stem cell-derived cardiomyocytes (ES-CMs) serve as potential sources for cardiac regenerative therapy. However, the immature sarcoplasmic reticulum (SR) function of ES-CMs prevents its application. In this report, we examined the effect of puerarin, an isoflavone compound, on SR function of murine ES-CMs. Methods: Murine ES-CMs were harvested by embryoid body-based differentiation method. Confocal calcium imaging and whole-cell patch clamps were performed to assess the function of SR. The mRNA expression levels of SR-related genes were examined by quantitative PCR. The protein expression of sarcoplasmic reticulum calcium-ATPase 2a (SERCA2a) was evaluated by immunofluorescent and western blot. Results: Long-term application of puerarin promotes basic properties of spontaneous calcium transient with increased amplitude, decay velocity, and decreased duration. Puerarin fails to alter I Ca,L but increases the Ca 2+ content of SR. Puerarin-treated ES-CMs have intact SR Ca 2+ cycling with more SR Ca 2+ reuptake. Long-term application of puerarin asynchronously upregulates the mRNA and protein expression of SERCA2a, as well as the transcripts of calsequestrin and triadin in developing ES-CMs. Application of puerarin during the stage of post-cardiac differentiation upregulates dose-dependently the transcripts of SERCA2a, phospholamban and tridin which can be reversed by the inhibitors of the PI3K/Akt and MAPK/ERK signaling pathways, but shows no effect on the protein expression of SERCA2a. Conclusion: This study demonstrates that long-term puerarin treatment enhances Ca 2+ reuptake and Ca 2+ content via upregulation of SERCA2a.

The urban heat island (UHI) effect has become increasingly prevalent and significant with the accelerated pace of urbanization, posing challenges for urban planners and policymakers. To reveal the spatiotemporal variations of the urban heat island effect in Jinan City, this study utilized Landsat satellite images from 2009, 2014, and 2019, employing the classic Mono-Window algorithm to extract land surface temperature (LST). Additionally, Geodetector was introduced to conduct a detailed analysis of the relationship between LST in Jinan City and land cover types (vegetation, water bodies, and buildings). The results indicate a significant increase in the severity of the urban heat island effect in Jinan from 2009 to 2019, with the central urban area consistently exhibiting a high-intensity core heat island. Suburban areas of Jinan show a clear trend of merging their heat island effects with the central urban area. The combined area of strong cool island effect zones and cool island effect zones within water bodies reaches 89.7%, while the combined proportion of heat island and strong heat island effect zones in building areas is 62.2%. Vegetation cover (FVC) exerts the greatest influence among all factors on the intensity level of the urban heat island effect. These findings provide a reliable basis for decision-making related to urban planning and construction in Jinan City.

With the insidiously growing impact of urban development on the environment, the issue of air quality has attracted extensive attention nationally and globally. It is of great significance to study the influence of urbanization on air quality for the rational development of cities. MODIS-MAIAC (Moderate Resolution Imaging Spectroradiometer-Multi-Angle Implementation of Atmospheric Correction) Aerosol optical depth (AOD) product, DMSP/OLS (Defense Meteorological Satellite Program/Operational Linescan System) and NPP/VIIRS (Suomi National Polar-orbiting Partnership/Visible Infrared Imaging Radiometer Suite) night-light were used to explore the spatiotemporal variation and correlation between AOD and urbanization development before and after the promulgation of environmental governance policies in Jinan City from 2009 to 2018. Results show that (1) the spatial distribution of AOD in Jinan had the characteristics of high in the north and low in the south, high in the west and low in the east, and low in some parts of the central region; there was a significant seasonal variation in time, with the highest AOD in summer and the lowest in winter. During 2009–2013, the annual average variation of AOD increased by 20.6%, while during 2014–2018, it decreased by 35.3%; (2) The distribution of night-light in Jinan City has progressively expanded, mirroring the city’s ongoing development. The spatial distribution of aerosols in urban areas was relatively low compared to the surrounding areas of the city. (3) From 2009 to 2013, there existed a significant positive correlation between the spatial and temporal distribution of AOD and night-light. However, from 2014 to 2018, with the implementation of environmental governance policies, this relationship shifted to a significant negative correlation between the spatial and temporal distribution of AOD and night-light. Through an analysis of the correlation between urban development and aerosol depth in Jinan City over the past decade, it can be concluded that urban development does not inevitably result in elevated AOD levels. Notably, the Jinan government has achieved remarkable results in controlling the atmospheric environment, as evidenced by recent years’ improvements.

The Ganjiang River, one of eight major tributaries of the Yangtze River, located in the western hinterland of the Cathaysia Block, SE China, has a length of 823 km and a drainage area of 82 809 km 2 , whose detrital zircons provide a valuable means to trace sediment provenances of the river and explore the crustal growth and evolution of the Cathaysia Block. In the current study, 389 concordia zircon U–Pb age spots and rare earth element (REE) contents, in combination with 201 Lu–Hf isotope analyses, have been determined. Oscillatory zoning, high Th/U ratios and REE distribution patterns indicate that most detrital zircon grains are of magmatic origin. The age can be further divided into seven groups: 130–185 Ma with a peak at 153 Ma (7 %); 217–379 Ma with a peak at 224 Ma (16 %); 390–494 Ma with a peak at 424 Ma (37 %); 500–698 Ma with a peak at 624 Ma (5 %); 716–897 Ma with a peak at 812 Ma (10 %); 902–1191 Ma with a peak at 976 Ma (13 %); and 2232–2614 Ma with a peak at 2471 Ma (5 %). The sources of almost all the zircon age groups can be found from the exposed rocks. In particular, Yanshanian, Hercynian to Indosinian, Pan-African, Grenvillian and Palaeoproterozoic–Archaean zircons can be mainly sourced from the northern Guangdong – southern Jiangxi – western Fujian region, while Caledonian zircons come from southern and central Jiangxi, and Jinningian zircons are from central and northern Jiangxi. Most determined zircon grains exhibit negative ε Hf ( t ) values and T DM2 ages of 797 to 4016 Ma with a wide peak at 1500–2100 Ma and a keen peak at 1824 Ma, suggesting that most zircons are sourced from the reworked ancient crustal materials or crust–mantle mixing. The zircon Hf model age cumulative probability diagram shows that rapid crustal growth took place at the Palaeo- to Mesoproterozoic and that about 90 % of the crust of the Cathaysia Block was formed before 1.5 Ga.

Background/Aims: The embryonic stem cell-derived cardiomyocytes (ES-CMs) serve as potential sources for cardiac regenerative therapy. However, the immature sarcoplasmic reticulum (SR) function of ES-CMs prevents its application. In this report, we examined the effect of puerarin, an isoflavone compound, on SR function of murine ES-CMs. Methods: Murine ES-CMs were harvested by embryoid body-based differentiation method. Confocal calcium imaging and whole-cell patch clamps were performed to assess the function of SR. The mRNA expression levels of SR-related genes were examined by quantitative PCR. The protein expression of sarcoplasmic reticulum calcium-ATPase 2a (SERCA2a) was evaluated by immunofluorescent and western blot. Results: Long-term application of puerarin promotes basic properties of spontaneous calcium transient with increased amplitude, decay velocity, and decreased duration. Puerarin fails to alter ICa,L but increases the Ca2+ content of SR. Puerarin-treated ES-CMs have intact SR Ca2+ cycling with more SR Ca2+ reuptake. Long-term application of puerarin asynchronously upregulates the mRNA and protein expression of SERCA2a, as well as the transcripts of calsequestrin and triadin in developing ES-CMs. Application of puerarin during the stage of post-cardiac differentiation upregulates dose-dependently the transcripts of SERCA2a, phospholamban and tridin which can be reversed by the inhibitors of the PI3K/Akt and MAPK/ERK signaling pathways, but shows no effect on the protein expression of SERCA2a. Conclusion: This study demonstrates that long-term puerarin treatment enhances Ca2+ reuptake and Ca2+ content via upregulation of SERCA2a.