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Oceanic water quality monitoring is essential for environmental protection, resource management, and ecosystem vitality. Optical remote sensing from space plays a pivotal role in global surveillance of oceanic water quality. However, the spatial resolution of current ocean color data products falls short of scrutinizing intricate small-scale marine features. This study introduces a hybrid model that fuses MODIS (Moderate Resolution lmaging Spectroradiometer) ocean color products with Sentinel-2 ‘s remote sensing reflectance data to generate high-resolution ocean color imagery, specifically investigating the diffuse attenuation coefficient at a wavelength of 490 nm (Kd490). To address the intricacies of coastal environments, we propose two complementary strategies to improve the accuracy of inversion. The first strategy leverages MODIS ocean color products alongside a geographic segmentation model to perform distinct inversions for separate marine zones, enhancing spatial resolution and specificity in coastal regions. The second strategy bolsters model interpretability during training by integrating predictions from conventional physical models into a Random Forest-based Regression Ensemble (RFRE) model. This study focuses on the coastal regions surrounding the Beibu Gulf, near Hainan Island in China. Our findings exhibit a strong concordance with MODIS products, achieving a monthly average coefficient of determination (R²) of 0.90, peaking at 0.97, and sustaining a monthly average root-mean-square error (RMSE) of less than 0.02. These results substantiate the model’s efficacy. Moreover, the annual trend analysis and localized assessment of the reconstructed Kd490 offer nuanced insights that surpass MODIS data, establishing a robust foundation for high-resolution water quality monitoring in coastal zones.

Abstract Background The association of longitudinal uric acid (UA) changes with cardiac conduction block risk is unclear. We aimed to identify the trajectories of UA and explore its association with cardiac conduction block. Methods A total of 67,095 participants with a mean age of 53.12 years were included from the Kailuan cohort in Tangshan, China, who were free of cardiac conduction block and with repeated measurements of UA from 2006 to 2012. UA trajectories during 2006 to 2012 were identified by group-based trajectory modeling. Cox proportional hazard regression models were used to assess the association of UA trajectories with cardiac conduction block. Results We categorized three observed discrete trajectories of UA during 2006–2012 period: low-stable, moderate-stable, and high-stable. Over a median follow-up of 6.19 years, we identified 1405 (2.09%) incident cardiac conduction block. Compared to those in the low-stable trajectory, the adjusted hazard ratios (HRs) (95% confidence interval [CI]) of cardiac conduction block in the moderate-stable and high-stable trajectory were 1.30 (1.16–1.47) and 1.86 (1.56–2.22), and HRs of atrioventricular block were 1.39 (1.12–1.72) and 2.90 (2.19–3.83), and HRs of bundle branch blocks were 1.27 (1.10–1.47) and 1.43 (1.13–1.79). Notably, although the average UA level in the moderate-stable UA trajectory group is within the normal range, the risk of cardiac conduction block has increased. Conclusions The moderate-stable and high-stable trajectories are associated with increased risk for new-onset cardiac conduction block. Monitoring UA trajectories may assist in identifying subpopulations at higher risk for cardiac conduction block.

Rammed earth, a commonly used building material in ancient times, differs from natural sedimentary layers in that it is more compact. Buildings constructed from historical rammed earth sites frequently encounter the issue of rainwater erosion. Microbially induced calcium carbonate precipitation (MICP) is commonly applied to sand soil treatment, yet reports on its use for stabilizing rammed earth are scarce. This study focused on the rammed earth of the Shanhaiguan Great Wall and explored the efficacy of MICP in mitigating rain erosion through permeation tests, splash experiments, and scouring trials. The findings indicate that the forms of rain erosion damage under MICP treatment vary across different operational conditions. In laboratory experiments, as the concentration of the cementation solution increases, the amount of calcium carbonate crystals also increases. However, the permeability, splash resistance, and rain erosion resistance initially increase and then decrease. When the cementation solution concentration is 1.0 mol/L, the penetration rate is the highest, lasting 712.55 s. The splash pit rate is the lowest, at only 1.2 mm, and the soil erosion rate is the lowest, at only 4.13%. The rain erosion resistance in the field test exhibit the same trend, and the optimal concentration is 1.2 mol/L. The optimal concentration mechanism involves the aggregation of calcium carbonate crystals at suitable cementation solution concentrations, which begin to fill the soil particle pores, effectively resisting rainwater erosion. At lower concentrations of the cementation solution, calcium carbonate crystals are merely adsorbed by soil particles without blocking the pores. Due to the high compressibility of rammed earth, which results in lower porosity, a higher concentration of the cementation solution leads to rapid pore clogging by excessive calcium carbonate crystals, which accumulate on the surface to form a white crust layer. The MICP technique can effectively alleviate rainwater erosion in rammed earth, and the optimal concentration needs to be tailored to the porosity of the rammed earth. This mechanism was also validated in field scouring experiments on the Shanhaiguan Great Wall’s rammed earth.

Optical frequency combs have emerged as a new generation of metrological tools, driving advancements in various fields such as free-space two-way time–frequency transfer, low-noise microwave source generation, and gas molecule detection. Among them, fiber combs based on erbium-doped fiber mode-locked lasers have garnered significant attention due to their numerous advantages, including low noise, high system integration, and cost-effectiveness. In this review, we discuss recent developments in erbium-doped fiber combs and analyze the advantages and disadvantages of constructing fiber combs utilizing different erbium-doped mode-locked fiber lasers. First, we provide a brief introduction to the basic principles of optical frequency combs. Then, we explore erbium-doped fiber combs implemented utilizing various mode-locking techniques, such as nonlinear polarization rotation (NPR), real saturable absorber (SA), and nonlinear amplifying loop mirror (NALM). Finally, we present an outlook on the future perspectives of erbium-doped fiber combs.

Laboratory analysis of returned Chang’E-5 samples from the lunar surface show their hydroxyl contents to be on the weak end of lunar hydration features.

The study of volatile elements on the Martian surface is a critical way to explore the geological evolution history of Mars. Volatile elements such as hydrogen (H), sulfur (S), and chlorine (Cl) on the Martian surface act as proxies for the potential aqueous or atmospheric environments that formed their corresponding phases. In this work, data collected from the Laser Induced Breakdown Spectroscopy and the Short Wave Infrared Spectroscopy of the Mars Surface Composition Detection onboard the Zhurong rover are employed to analyze the volatile elements (H, S, Cl) and their carriers in materials throughout the landing site. We found that S primarily concentrates in gypsum and other sulfates, and the carriers of H include hydrous mineral combinations such as gypsum, hydrated silica, and ferrihydrite. These altered minerals are probably the products of acid weathering processes, which may have occurred mostly during the relatively humid period of the Zhurong landing site since Amazonian.

This paper reports a complete solution for short-acquisition-time, flood-illumination, and non-scanning 3D imaging. Based on an InGaAs/InP 64×64 Geiger-mode avalanche photodiode array, we developed a single-photon imaging Lidar with a field of view of 19.2 mrad. A spatiotemporal dominant imaging method was also applied for depth estimation under high daytime background noise conditions. In the field tests, 3D imaging information was effectively extracted from objects with strong solar background light. An acquisition time of only 0.5 ms to 4 ms was needed for a building target approximately 1300 m away. The experimental results show that the Lidar and its data processing method have the potential for dynamic scenarios that require high performance 3D imaging, such as vehicle navigation, airborne mapping, and moving target monitoring.

Objective: To investigate the effect and its underlying molecular mechanisms of essential oil from Saussurea costus in esophageal cancer cell line Eca109. Methods: The chemical composition of essential oil from Saussurea costus was investigated by gas chromatography-mass spectrometry (GC-MS). The anti-proliferative, anti-migrative, and apoptotic effects of essential oil from Saussurea costus against Eca109 cells were analyzed. Moreover, the expression of proteins associated with cell cycle, metastasis, and apoptosis was determined. Results: GC-MS analysis showed that essential oil from Saussurea costus was predominantly comprised of sesquiterpenes. Saussurea costus essential oil inhibited the viability of Eca109 cells in a dose-and time-dependent manner with IC50 values of (24.29±1.49), (19.16±2.27) and (6.97±0.86) μg/mL at 12, 24, and 48 h, respectively. The expression levels of target proteins in the cell cycle (phase G1/S), including cyclin D1, p21, and p53, were affected by Saussurea costus essential oil. The essential oil also downregulated the expression of metastasis-related proteins MMP-9 and MMP-2. Moreover, it induced apoptosis of Eca109 cells through the mitochondrial pathway, as well as inhibition of STAT3 phosphorylation. Conclusions: The essential oil from Saussurea costus exhibited anti-proliferative, anti-migrative, and apoptotic effects on Eca109 cells, and could be further explored as a potential anti-esophageal cancer agent.

We present the porcine skin ablation using a mid-infrared high-repetition-rate picosecond pulse burst laser. A burst-mode pulse with a repetition rate of 16.32 MHz was generated from a home-built difference frequency generation (DFG) system operating at 3 μm. Within each burst, there were 16 equally spaced 8.5 ps sub-pulses at an intra-burst repetition rate of ∼3.3 GHz. To study the laser-tissue interaction, laser powers of 1 to 2 W, and scanning times from 1 to 10 with spot size of ∼50 μm were applied to irradiate the fresh porcine skin. The results demonstrate that the burst-mode pulse with modest peak power density of MW/cm2 is efficient for tissue ablation. The optimized ablation depth increased with the average power and scanning times, reaching a maximal incision depth of 150 μm. Thanks to the high repetition rate of intra-burst pulse and high absorption of radiation, the ablation width and thermal effect width kept within 50 μm and 25 μm in all control groups. It is believed that as the first demonstration, such mid-infrared burst-mode laser radiation with modest power intensity is of great potential to realize micron penetration depth and low thermal effect in high-precision surgery applications.

It has been established that long-chain coding RNA (lncRNA) SLC25A25-AS1 is associated with cancer progression. However, the roles and mechanisms of SLC25A25-AS1 in prostate cancer (PC) have not been reported in the literature. The present study explored the relationship between SLC25A25-AS1 expression and PC progression via comprehensive analysis. The pan-cancer expression of SLC25A25-AS1 was identified using data from The Cancer Genome Atlas (TCGA) database and tissue specimens from our hospital. The expression levels of SLC25A25-AS1 in various subgroups based on the clinical features were identified. The prognostic value of SLC25A25-AS1 and SLC25A25-AS1 co-expressed lncRNAs in PC patients was assessed by survival analysis and ROC analysis, and prognosis-related risk models of SLC25A25-AS1 were constructed. The relationship between SLC25A25-AS1 and the PC immune microenvironment was investigated using correlation analysis. SLC25A25-AS1 expression in PC was significantly increased and correlated with the T stage, clinical stage, Gleason score (GS), and dismal prognosis. SLC25A25-AS1 overexpression exhibited good performance in evaluating the prognosis of PC patients. The area under the curves (AUCs) of the 1-, 3-, and 5-year overall survival (OS) for SLC25A25-AS1 was 1, 0.876, and 0.749. Moreover, the AUCs for the 1-, 3-, and 5-year progress free interval (PFI) for SLC25A25-AS1 were 0.731, 0.701, and 0.718. SLC25A25-AS1 overexpression correlated with the infiltration of CD8 T cells, interstitial dendritic cells (IDC), macrophages and other cells. AC020558.2, ZNF32-AS2, AP4B1-AS1, AL355488.1, AC109460.3, SNHG1, C3orf35, LMNTD2-AS1, and AL365330.1 were significantly associated with SLC25A25-AS1 expression, and short OS and PFI in PC patients. The risk models of the SLC25A25-AS1-related lncRNAs were associated with a dismal prognosis in PC. Overall, SLC25A25-AS1 expression was increased in PC and related to the prognosis and PC immune microenvironment. The risk model of SLC25A25-AS1 have huge prospect for application as prognostic tools in PC.

An electrochemical transient iodination and coupling reaction has been designed for constructing selenylated 4-anilinocoumarins via the domino reactions of 4-anilinocoumarins and diorganyl diselenides under base-, chemical oxidant- and external electrolyte-free conditions.

As part of China’s Tianwen-1 Mars mission, the Mars Surface Composition Detector (MarSCoDe) instrument on the Zhurong rover adopts laser-induced breakdown spectroscopy (LIBS) to perform chemical component detection of the materials on the Martian surface. However, it has always been a challenging issue to achieve high accuracy in LIBS quantification. This study investigated the effect of chemometrics and spectral data preprocessing approaches on LIBS quantification accuracy based on different chemometrics algorithms and diverse preprocessing methods. A total of 2340 LIBS spectra were collected from 39 kinds of geochemical samples by a laboratory duplicate model of the MarSCoDe instrument. The samples and the MarSCoDe laboratory model were placed in a simulated Martian atmosphere environment based on equipment called the Mars-Simulated Detection Environment Experiment Platform (MarSDEEP). To quantify the concentration of MgO in the samples, we employed two common LIBS chemometrics; i.e., partial least squares (PLS) and a back-propagation neural network (BPNN). Meanwhile, in addition to necessary routine preprocessing such as dark subtraction, we used five specific preprocessing approaches, namely intensity normalization, baseline removal, Mg-peak wavelength correction, Mg-peak feature engineering, and concentration range reduction. The results indicated that the performance of the BPNN was better than that of the PLS and that the preprocessing of Mg-peak wavelength correction had the most prominent effect to improve the quantification accuracy. The results of this study are expected to provide inspiration for the processing and analysis of the in situ LIBS data acquired by MarSCoDe on Mars.

From June 2008 to August 2013, approximately 67 kt of CO2 was injected into a deep saline formation at the Ketzin pilot CO2 storage site. During injection, 3D seismic surveys have been performed to monitor the migration of sequestered CO2. Seismic monitoring results are limited by the acquisition and signal-to-noise ratio of the acquired data. The multiphysical reservoir simulation provides information regarding the CO2 fluid behavior, and the approximated model should be calibrated with the monitoring results. In this work, property models are delivered from the multiphysical model during 3D repeated seismic surveys. The simulated seismic data based on the models are compared with the real data, and the results validate the effectiveness of the multiphysical inversion method. Time-lapse analysis shows the trend of CO2 migration during and after injection. [ABSTRACT FROM AUTHOR]

RNA modification of m6A/m5C/m1A contributes to the occurrence and development of cancer. Consequently, this study aimed to investigate the functions of m6A/m5C/m1A regulated genes in the prognosis and immune microenvironment of hepatocellular carcinoma (HCC). The expression levels of 45 m6A/m5C/m1A regulated genes in HCC tissues were determined. The functional mechanisms and protein–protein interaction network of m6A/m5C/m1A regulated genes were investigated. The Cancer Genome Atlas (TCGA) HCC gene set was categorized based on 45 m6A/m5C/m1A regulated genes, and survival analysis was used to determine the relationship between the overall survival of HCC patients in subgroups. Cox and least absolute shrinkage and selection operator (LASSO) regression analyses were used to construct the risk model and nomogram for m6A/m5C/m1A regulated genes. The relationships between m6A/m5C/m1A regulated gene subsets and risk model and immune cell infiltration were analyzed using CIBERSORT. m6A/m5C/m1A regulated genes were involved in mRNA and RNA modifications, mRNA and RNA methylation, mRNA and RNA stability, and other processes. There was a statistically significant difference between cluster1 and cluster2 groups of genes regulated by m6A/m5C/m1A. The prognosis of cluster1 patients was significantly better than that of cluster2 patients. There were statistically significant differences between the two cluster groups in terms of fustat status, grade, clinical stage, and T stage of HCC patients. The risk model comprised the overexpression of YBX1, ZC3H13, YTHDF1, TRMT10C, YTHDF2, RRP8, TRMT6, LRPPRC, and IGF2BP3, which contributed to the poor prognosis of HCC patients. The high-risk score was associated with prognosis, fustat status, grade, clinical stage, T stage, and M stage and was an independent risk factor for poor prognosis in HCC patients. High-risk score mechanisms included spliceosome, RNA degradation, and DNA replication, among others, and high-risk was closely related to stromal score, CD4 memory resting T cells, M0 macrophages, M1 macrophages, resting mast cells, CD4 memory activated T cells, and follicular helper T cells. In conclusion, the cluster subgroup and risk model of m6A/m5C/m1A regulated genes were associated with the poor prognosis and immune microenvironment in HCC and are expected to be the new tools for assessing the prognosis of HCC patients.

Water-in-oil (W/O) microemulsions exhibit delivery matrix and exhibit poor lipid solubility. Therefore, increasing the stability of W/O microemulsions is necessary to broaden their applications. In our experiment, a protein microemulsion system was constructed and its stability was investigated. The effects of surfactants, co-surfactants, quality ratio of them (Km) and hydrophilic-lipophilic balance (HLB) values were determined by using the pseudo-ternary phase diagrams and the area of microemulsions (MEs) as the indexes. The results showed that MEs’ stability was the best when the limonene was used as oil phase, Tween 20 + span 80 as the surfactant, and anhydrous alcohol as co-surfactant, if and only if HLB = 6.0 and Km = 3:1. Under this condition, the area of micro-emulsion was the largest, and the quality of microemulsion was better when the mass ratio of oil phase and emulsifier was 7:5.The protein microemulsion was a water-in-oil type, with a particle size of 1.41 ± 0.03 μm, containing 1127.37 ± 30.87 μg/g of proteins. Moreover, the temperature, light, and sample observation tests showed that the solution’s protein retention rate was lower than those in the microemulsion. Low-concentration NaCl, less than 9% of glucose and maltose exerted no significant influence on the protein microemulsion stability.