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关键词： Above-ground biomass   plant height   SAR texture indices   vegetation indices   precision agriculture  

摘要： Accurate estimation of above-ground biomass (AGB) and plant height is essential for precision crop management. However, traditional methods like synthetic aperture radar (SAR) data and optical vegetation indices (VIs) often face signal saturation at medium to high AGB levels. To address this, we proposed two polarization texture indices, i.e., Ratio SAR Texture Index (RSTI) and Normalized Difference SAR Texture Index (NDSTI), derived from Sentinel-1 (S-1) data to estimate crop AGB and height. We further investigated their integration with S-1 polarizations and Sentinel-2 (S-2) VIs using four machine learning algorithms to enhance retrieval performance. Results revealed that both RSTI and NDSTI outperformed individual polarizations, polarization texture features, and most of VIs in estimating crop AGB and height. Furthermore, the combination of these indices with S-2 VIs significantly improved the retrieval accuracy. The optimal models achieved R2 values up to 0.75 and 0.80 for maize and soybean AGB, 0.89 and 0.94 for maize and soybean height, respectively. Validation with an independent dataset confirmed the robustness and transferability of the proposed models for estimating maize AGB and height. Overall, RSTI and NDSTI, along with their integration with optical VIs, provide an effective approach for improving crop AGB and height estimation for agricultural monitoring.

摘要： Synthetic cannabinoid receptor agonists (SCRAs) are molecules that interact with the CB1 receptor and may exhibit greater psychoactive effect than CB1’s natural agonists. Determining new SCRAs by conducting bioassays can be time-consuming and may or may not yield positive results. Recent development in machine learning has demonstrated its usefulness as a complementary tool for prioritised bioassay testing and thus, improving the chances of getting a positive hit. In this study, we explored the use of different machine learning algorithms to predict specifically if a molecule is an active CB1 agonist. We achieved median scores of 0.937, 0.814 and 0.933 in terms of accuracy, precision and recall, respectively, for a moderately imbalanced dataset with the minority class occupying 22% of the test dataset. We carried out extensive evaluation and identified limitations to our model. We also demonstrated the use of Shapley values for explainability which appeared consistent with traditional structure-activity relationship (SAR) studies that accurately pinpoints importance of linkages to CB1 agonists’ activity.

关键词： Agaricus blazei   Beta glucan extract   Ionizing radiation   Radioprotection  

摘要： Ionizing radiation (IR) is an effective cancer therapy but may also cause damage to surrounding healthy tissues. This study evaluated the radioprotective efficacy of oral (1,3/1,6) beta-glucan extract from Agaricus blazei mushrooms against IR-induced damage in total body-irradiated rats, focusing on oxidative stress markers, hematological parameters, and liver cytotoxicity. Forty male Wistar albino rats were divided into four groups: unexposed controls (Group I), radiation-only (6 Gy X-ray, Group II), beta-glucan-only (250 mg/kg/day for 7 days, Group III), and beta-glucan + radiation (Group IV). Rats exposed to radiation alone exhibited elevated malondialdehyde (MDA), reduced glutathione (GSH), total antioxidant capacity (TAC), catalase activity, decreased white blood cells (particularly lymphocytes), and severe liver damage. Pre-treatment with beta-glucan significantly increased GSH, TAC, and catalase levels while reducing MDA, restored WBC/lymphocyte counts, and preserved liver architecture. Beta-glucan alone caused no morphological or functional alterations, indicating safety. These findings demonstrate beta-glucan's ability to mitigate IR-induced oxidative stress, hematological disruption, and hepatic cytotoxicity, likely through enhanced antioxidant defenses.

关键词： Antimicrobial activity   Molecular docking studies   Oxadiazol   Piperidin-methanone   Synthesis  

摘要： A set of novel 1,2,4-oxadiazol based piperidin-1-yl-methanone analogues (5a-k) was synthesized from 3-phenyl-5-(4-(piperidin-4-yl)phenyl)-1,2,4-oxadiazole (3) via a sequential hydrolysis, cyclization and the Schotten-Baumann reaction. The structures of synthesized compounds were characterized using ¹H NMR, ¹³C NMR and mass spectrometry data. Moreover, all compounds were evaluated for their preliminary antimicrobial activity against Gram-negative, Gram-positive bacterial, as well as fungal pathogens, employing the disk diffusion method. Most of the evaluated compounds displayed exceptional antimicrobial activity, when compared with standard Ampicillin, Griseofulvin. Notably, compounds 5b, 5e, 5i, 5j and 5k exhibited significant anti-bacterial activity, with zone of inhibition of 20–25 mm at 50 μg/ml and MIC values ranging from 1.6–2.2 μg/mL. The antifungal activity revealed MIC values in the range of 1.7–1.9 μg/mL. Molecular docking studies were conducted against penicillin-binding protein (PBP, PDB ID: 3TTZ), a key enzyme involved in bacterial cell wall biosynthesis. The synthesized compounds exhibited favorable binding interactions within the active site of PBP through H-bonds and hydrophobic interactions, supported by stable binding energies, with crucial residues. These results suggest that the developed 1,2,4-oxadiazol based piperidin-1-yl-methanone analogues favorable stability,

关键词： Ethylene   Quartz crystal microbalance   Sensor   Strawberry  

摘要： Ethylene (C₂H₄) is a key plant hormone that accelerates the ripening and post-harvest spoilage of climacteric fruits. Therefore, sensitive monitoring of trace C₂H₄ in storage environments is crucial for intelligent preservation. In this work, a quartz crystal microbalance (QCM) sensor modified with HKUST-1 metal-organic framework was developed for ultrasensitive detection of C₂H₄. Benefiting from the high surface area and abundant adsorption sites of HKUST-1, the sensor exhibits a strong frequency shift response toward C₂H₄ in the concentration range of 50-2400 ppb. The sensor achieves rapid response and recovery times of 27 s and 45 s, respectively. A good logarithmic relationship between frequency shift and C₂H₄ concentration was observed with a correlation coefficient of R² = 0.9839, enabling reliable quantitative analysis. The sensor also demonstrates good repeatability, long-term stability over 4 weeks, and anti-humidity interference within 40-90% RH. Moreover, practical monitoring experiments reveal a clear correlation between environmental C₂H₄ concentration, sensor response, and the spoilage behavior of strawberries during storage. These results indicate that the HKUST-1 based QCM sensor provides a simple, low-cost, and highly sensitive strategy for real-time C₂H₄ monitoring in fruit storage environments.

关键词： 1-second single-lead ECG   Deep learning for biomedical signals   Electrocardiography (ECG)   QRS complex detection  

摘要： Electrocardiography (ECG) plays a crucial role in detecting cardiovascular diseases, yet precise QRS complex delineation in ultrashort (e.g., 1-second) recordings remains an open challenge. Existing methods, which typically focus on R-peak detection or fixed-length segmentation, fail to achieve accurate boundary localization and require longer durations. To address these issues, we propose HiDC-QRS, a Hierarchical Dilated Convolutional Network featuring a principled re-design of feature hierarchy and learning dynamics. The innovations are twofold: (1) a hierarchical dilated convolution scheme tailored for one-dimensional ECG to natively capture multi-scale temporal features, with each encoder layer characterizing distinct ECG components, thereby forming a physiologically interpretable feature hierarchy; and (2) a novel weighted output aggregation mechanism that explicitly balances the contributions of multi-scale feature representations and establishes direct gradient feedback paths during training, enabling joint optimization of all network layers for detecting a wide spectrum of waveform characteristics. In this work, we introduce a high-quality clinical dataset to evaluate HiDC-QRS and address the scarcity of ultrashort ECG resources. Our method achieves state-of-the-art performance, with a sensitivity of 0.970 and a positive predictive value of 0.995. Additionally, the proposed model demonstrates robust zero-shot learning across four public datasets, indicating its adaptability and potential for clinical application. We make our dataset and code publicly available on https://***/neu2270Ma/HiDC-QRS/releases

来源 ScienceCitationIndex... ScienceDirectJournal 详细信息

关键词： Cancer   Immunotherapy   T cell activation   Small molecule inhibitors   PD-1 inhibitors   Immune checkpoints   PD-1   PD-L1   T cell reporter cells  

摘要： Antibodies that block PD-1 signaling, known as immune checkpoint inhibitors (ICIs), have revolutionized cancer treatment. Small molecule inhibitors of the PD-1/PD-L1 interaction could serve as promising alternatives to antibody-based ICIs, offering advantages including reduced cost, the option of oral administration, and their small size allows for deeper tissue penetration. Numerous such compounds have been described, but many have not been evaluated in well-defined cellular systems, and comparative studies are scarce. We tested eleven small molecule inhibitors using Jurkat-PD-1-reporter cells activated by stimulator cells expressing PD-L1. Additionally, their effects on T cell reporter activation and viability were evaluated. We found that ARB-272572, INCB086550, Evixapodlin, and PD-1/PD-L1 Inhibitor 3 completely reversed the inhibitory effects of PD-1. Except for PD-1/PD-L1 Inhibitor 3, these compounds blocked PD-1 inhibition with EC₅₀ values in the low nanomolar range. Interestingly, seven PD-1 inhibitors failed to fully block PD-1 inhibition in our cellular assay. BMS-1166 and PD-L1-IN3 showed some blocking capacity but could not fully restore the activation of PD-1 reporter cells. AUNP-12, BMS1, BMS202, CA170, and PD-1/PD-L1-IN-9 were ineffective at reducing PD-1-mediated reporter inhibition. Moreover, our data indicate that adverse effects on T cell reporter activation compromise the activity of several of the tested compounds. In summary, our results revealed that the majority of small molecule PD-1/PD-L1 blockers possess a limited capacity to reverse PD-1 inhibition in a T cell reporter platform and highlight the importance of cellular assays to assess the therapeutic potential of drugs targeting the PD-1/PD-L1 axis.

关键词： 1,3-Propanediol   Activated carbon   Chitosan   Clostridium butyricum   Dynamic metabolic flux analysis   Lactic acid  

摘要： The anaerobic fermentation of crude glycerol to 1,3-propanediol by Clostridium butyricum is energetically favorable due to the low stirring rate and unsterilized fermentation environment. However, its efficiency is severely limited by the accumulation of acid by-products. Although metabolic engineering is commonly employed to overcome such challenges, the inherent oxygen sensitivity of C. butyricum significantly hinders genetic modification and metabolic analysis under the required conditions. Therefore, we adopted an alternative strategy of supplementing renewable materials to regulate by-products formation and improve the 1,3-propanediol concentration. Among them, chitosan could reduce the concentration of most by-products, increasing the concentration and yield of 1,3-propanediol to 53.55 g/L and 0.57 g/g. At the same time, activated carbon could achieve co-production of 1,3-propanediol (62.12 g/L) and lactic acid (38.74 g/L) through selective adsorption of by-products. Combined with the adsorption equation-assisted dynamic metabolic flux analysis developed in this work, we demonstrated the by-product regulation produces more NADH and brings dynamic balance to the reducing power. This work offers enlightenment and reference for a similar production process, which is of great potential to reduce the concentration of most by-products in future large-scale 1,3-propanediol production.

关键词： JAK2   Lung cancer   PD-1   PD-L1   RVX-208   STAT3  

摘要： Immunotherapies, particularly anti-PD-1 antibodies, have emerged as standard first-line treatments for non-small cell lung cancer (NSCLC). RVX-208, derived from resveratrol, has recently completed Phase III clinical trials for atherosclerosis in the United States. In this study, we demonstrate for the first time that RVX-208 suppresses lung cancer growth in vivo by enhancing T cell-mediated immunity notably rather than directly suppressing lung cancer cell proliferation. Mechanically, RVX-208 interfered with janus kinase 2 (JAK2) to reduce its phosphorylation, reduced both the programmed death-1 (PD-1) expression in T lymphocytes and programmed death-ligand 1 (PD-L1) expression in lung cancer cells, thereby inhibiting the growth of lung cancer cells co-cultured with T lymphocytes in vitro. Furthermore, RVX-208 enhanced the anti-tumor activity of anti-PD-1 antibody in lung cancer cells that were co-cultured with lymphocytes in vitro. Consistent with these findings, RVX-208 treatment also reduced PD-1 levels in T cells from tumor bearing mice in vivo. Collectively, these results identify RVX-208 as a promising small-molecule immunotherapeutic agent for the treatment of lung cancer.