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关键词： Digital soil mapping   Sentinel   Soil organic carbon   Spatial prediction   Remote sensing  

摘要： Accurate mapping of soil organic carbon (SOC) using optical remote sensing is often constrained by persistent cloud cover, which limits data availability in many regions. While recent studies have explored the feasibility of radar sensors for SOC mapping to overcome this limitation, they have predominantly relied on backscatter features, largely overlooking the potential of interferometric coherence. To address this gap, this study assessed the potential of synergistically using backscatter/coherence observations from Sentinel-1 and optical data from Sentinel-2 for mapping SOC across the Iberian Peninsula. Backscatter, coherence, optical, and traditional auxiliary data (terrain and climate) were utilized as input features, and their various combinations were integrated with the LUCAS 2018 soil database to develop machine learning-based SOC prediction models. We evaluated how the temporal interval of backscatter composites and the temporal baseline of coherence data affected model performance. Both radar metrics showed strong predictive power for SOC, and their temporal configurations substantially affected modeling performance. Backscatter images with a monthly interval achieved the best performance, whereas longer intervals progressively decreased predictive accuracy. Models trained on coherence with shorter temporal baselines outperformed those with longer temporal baselines. The joint use of these two radar metrics improved predictive accuracy (R² = 0.42), surpassing models that only used Sentinel-2 optical data (R² = 0.38). Our results demonstrate promising prospects of coherence/backscatter data as substitutes or complements to optical data for SOC mapping. Integrating these three complementary and relatively independent remote sensing sources notably improved model performance, achieving accuracy no lower than models based on traditional auxiliary data. Variable importance analysis indicated that radar-derived backscatter and coherence we

关键词： 脊髓损伤   川芎嗪   Keap-1/Nrf2信号通路   铁代谢   铁死亡   工程化组织构建  

摘要： 背景:脊髓损伤的临床治疗是世界性的医学难题,目前尚无理想方法。中医药治疗脊髓损伤具有一定优势,尤其是行气活血中药川芎的有效成分单体川芎嗪,已被证实对脊髓损伤后的神经炎症、细胞凋亡等病理反应具有显著抑制作用,对脊髓损伤修复具有一定的促进作用,极具应用潜力,但是其相关作用机制尚不清楚。目的:探讨川芎嗪对脊髓损伤后Kelch样环氧氯丙烷相关蛋白1/核因子E2相关因子2(Keap-1/Nrf2)信号通路及铁代谢的调节作用,分析其神经保护作用的相关机制。方法:将36只SD大鼠随机分为假手术组、模型组和川芎嗪组,每组12只;假手术组仅行椎板切除术,术后每日给予生理盐水腹腔注射;模型组和川芎嗪组制备脊髓损伤模型,术后每日分别给予生理盐水和川芎嗪腹腔注射。术后4周取材,采用尼氏染色观察神经元形态,普鲁士染色观察铁沉积,铁检测试剂盒检测脊髓组织铁含量,免疫组化检测Keap-1、铁蛋白重链1和铁蛋白轻链表达,免疫荧光检测Nrf2表达,Western blot检测Nrf2表达、铁蛋白重链1和铁蛋白轻链蛋白表达量,RT-PCR检测Nrf2、Keap-1、铁蛋白重链1和铁蛋白轻链的mRNA表达。结果与结论:①尼氏染色结果显示,假手术组神经元结构正常,模型组神经元结构紊乱,川芎嗪组神经元结构较模型组改善;②普鲁士染色结果显示,模型组和川芎嗪组阳性平均吸光度值显著多于假手术组(P<0.01),川芎嗪组阳性平均吸光度值显著少于模型组(P<0.01);③铁含量检测结果显示,模型组和川芎嗪组铁含量显著多于假手术组(P<0.01),川芎嗪组铁含量显著少于模型组(P<0.01);④免疫组化结果显示,模型组和川芎嗪组Keap-1平均吸光度值显著多于假手术组(P<0.01),而铁蛋白重链1和铁蛋白轻链平均吸光度值显著少于假手术组(P<0.01);川芎嗪组Keap-1平均吸光度值显著少于模型组(P<0.01),而铁蛋白重链1和铁蛋白轻链平均吸光度值显著多于模型组(P<0.01);⑤免疫荧光结果显示,模型组和川芎嗪组Nrf2表达平均吸光度值显著少于假手术组(P<0.01),川芎嗪组Nrf2表达平均吸光度值显著多于模型组(P<0.01);⑥Western blot结果显示,模型组和川芎嗪组Nrf2表达、铁蛋白重链1和铁蛋白轻链蛋白相对表达量显著少于假手术组(P<0.01),川芎嗪组Nrf2、铁蛋白重链1和铁蛋白轻链蛋白相对表达量显著多于模型组(P<0.01);⑦RT-PCR结果显示,模型组和川芎嗪组Keap-1 mRNA相对表达量显著多于假手术组(P<0.01),而Nrf2、铁蛋白重链1和铁蛋白轻链的mRNA相对表达量显著少于假手术组(P<0.01);川芎嗪组Keap-1 mRNA相对表达量显著少于模型组(P<0.01),而Nrf2、铁蛋白重链1和铁蛋白轻链mRNA相对表达量显著多于模型组(P<0.01);⑧提示川芎嗪可调节脊髓损伤后Keap-1/Nrf2信号通路及其调控的铁蛋白重链1和铁蛋白轻链表达,继而改善铁代谢紊乱,有利于脊髓损伤修复。

关键词： 02.30. Jr   Analytical solutions   Auto-Bäcklund transformation   Nonlinear waves   Painlevé analysis   Variable-coefficients pKP-BKP equation  

摘要： The two versions of $(3+1)$-dimensional variable coefficients combined pKP-BKP equations, which describe complex nonlinear wave phenomena, are examined in this work. The Painlevé analysis technique is employed to examine the integrability and nonlinear characteristics of the mentioned equations. Using this approach, both the considered equations are found completely Painlevé integrable. The auto-Bäcklund transformation technique is applied to generate various analytical solutions for both the equations including complex, rational, exponential, and linear type solutions, capturing rich nonlinear behaviors. Additionally, alternative techniques such as tan , tanh , exp  type-I and type-II methods are employed to drive kink, anti-kink and anti-bell shaped solutions, which illustrate the nonlinear interaction mechanisms inherent in the system. Three-dimensional graphs illustrate the behaviour of all the obtained solutions under different coefficients and parameters, highlighting the complexity of nonlinear wave dynamics. The obtained results not only expose the complex behaviour of nonlinear wave phenomena but also confirm the effectiveness of the employed techniques in modeling a wide range of physical systems. This study also provides a meaningful contribution to ongoing research in the field of nonlinear mathematical physics and engineering.

关键词： Candesartan   Chemotherapy   Cisplatin   Inflammation   Oxidative stress  

摘要： Cisplatin (CIS) is effective chemotherapeutic agent, but its clinical use is limited by adverse effects, including cardiotoxicity. Safe cardioprotective agents that can be rapidly translated into oncology practice remain an unmet need. This study evaluated whether candesartan (CAN), a clinically approved angiotensin II receptor blocker (ARB), protects against CIS-induced myocardial injury. Male Wistar rats were randomized into control, CAN, CIS, and CAN+CIS groups. CAN (5 mg/kg, oral) was administered for 10 days and CIS (7 mg/kg, i.p.) was injected on day 7. Serum cardiac biomarkers were assessed, oxidative and inflammatory mediators were quantified in cardiac tissue, and histopathology and immunohistochemistry were performed. CIS caused marked myocardial injury, evidenced by elevated cTnI, CK-MB, AST, and LDH, structural degeneration, and necrosis. Oxidative stress was pronounced, with increased lipid peroxidation and MPO activity and depleted antioxidant defenses, accompanied by downregulation of cytoglobin. CAN significantly attenuated biochemical and histological injury, restored redox homeostasis, and preserved cytoglobin expression. CIS also upregulated TLR-4, NF-κB, IRF-3, c-Fos, c-Jun, iNOS, and pro-inflammatory cytokines, whereas CAN markedly suppressed these changes. Molecular docking analysis showed the binding of CAN with cytoglobin, NF-κB p65, IRF-3, and c-Fos/c-Jun complex. In conclusion, CAN confers protection against CIS-induced myocardial damage by mitigating oxidative stress, enhancing antioxidants, and suppressing TLR-4/NF-κB/IRF-3/AP-1 signaling. These findings highlight CAN as a promising adjunct to alleviate CIS-induced cardiotoxicity and preserve cardiovascular health in cancer patients undergoing CIS chemotherapy. However, further investigations and clinical trials are needed to validate these preclinical data.

关键词： Aluminium-air battery   Corrosion inhibitor   Density functional theory   Electrochemical analysis   Electronic properties   Organic molecules  

摘要： The corrosion inhibition of 3-Methyl-1,2-cyclopentanedione (3-MCP) and 2,6-dimethoxyphenol (2,6-DMP) on commercial 1060 pure aluminium in 1 M KOH solution was investigated to enhance the durability of Aluminium-air batteries. The inhibition performance was evaluated using experimental techniques and computational approaches. Open circuit potential (OCP) and potentiodynamic polarization (PDP) results indicate that, depending on concentration effects, both compounds function predominantly as cathodic inhibitors, resulting negative shift in potential. The highest inhibition efficiency was obtained at 5 mM 3-MCP, demonstrating better inhibitory performance compared to 2,6-DMP. Electrochemical impedance spectroscopy (EIS) revealed inhibition efficiencies of 31.53% and 29.09% for 3-MCP and 2,6-DMP, respectively, while weight loss tests showed inhibition efficiencies of 17.69% and 16.64%. Density functional theory (DFT) analysis of global and local reactivity descriptors demonstrated more favourable electronic characteristics for 3-MCP, in good agreement with experimental findings, confirming its potential as an effective corrosion inhibitor for aluminium–air battery applications.

关键词： Confocal microscopy   Hyperspectral imaging   Multispectral   Multiplexing  

摘要： Multispectral imaging is a powerful technique that can detect subtle differences in the fluorescence expression of a species based on its reaction to its environment. These subtle differences offer a powerful contrast agent that can be used to identify new compounds for novel medicines. A high spectral resolution is crucial for this approach, since small changes in a species’ spectral signature can indicate meaningful changes within the local environment. Multispectral confocal imaging is slow because single-point confocal techniques have fundamental signal collection limitations, and currently, no massively multiplexed measurement technique offers high-resolution simultaneous multispectral measurement. Multiplexing with a window scanning multipoint confocal microscope, offers new spatially encoded spectral measurements on dense image sensors by sweeping spectral bands with a dedicated window scanner. We present a 32x32 point multiplexed confocal microscope that captures 22 spectral bands simultaneously at a real-time image frequency of 1 Hz over the entire spectral range of 450 nm to 650 nm.

关键词： Ischemia/reperfusion   L-Citrulline   Hydrogel   SIRT-1   Oxidative Stress   Inflammation  

摘要： Testicular torsion is a urological emergency that interrupts blood flow, resulting in ischemia/reperfusion injury (I/R I) that compromises testicular function and architecture. L-citrulline (L-Cit), a nitric oxide precursor with antioxidant capabilities, has been demonstrated to help lessen testicular injury. This study aims to provide novel insights by comparatively evaluating the immediate and effective anti-ischemic effects of free L-Cit versus its hydrogel formulation on reproductive outcomes and testicular histoarchitecture in a rat model of testicular torsion/detorsion (T/TD) injury .

关键词： 1,2,4-Triazoles   Biological compounds   Corrosion inhibitors   Luminescent   Metal-organic frameworks  

摘要： Over the last two decades, triazoles have been a fascinating heterocyclic scaffold for the synthesis and design of versatile medicinal compounds. 1,2,4- triazoles are extensively employed for their numerous clinical roles, i.e., antifungal, antiviral, antibacterial, anti-inflammatory, and anti-tubercular owing to its enzyme-inhibitory activities that targets CYP51, aromatase, and MmpL3. Hence, five-membered aromatic 1,2,4- triazoles have gained potent attention owing to their flexible synthesis route that allows the development of biological compounds in an easy manner. This comprehensive study systematically portrays different conventional and green chemistry approaches for synthesis, different biological properties, and therapeutic potential of 1,2,4-triazole derivatives. Structural properties elucidate the influence of substitution patterns on molecular stability, electronic distribution, and reactivity, which underpin their functional applications. The present study emphasized emerging therapeutic potential of 1,2,4-triazole-MOFs, including designing of controlled drug delivery systems, theronostics, biosensors, and corrosion inhibitors. The structural flexibility, surface functionality, biocompatibility, and biodegradability not only enable MOFs for encapsulating myriad therapeutics (small molecules-macromolecules) but also protect compounds from enzymatic degradation. Moreover, the intrinsic magnetic and luminescent features of certain 1,2,4-linked MOFs pose a versatile arena for the development of theranostics, real-time imaging, and combined drug delivery.

关键词： Rotors   Bars   Stators   Voltage measurement   Stator windings   Oscillators   High-temperature superconductors   Torque   Resistance   Wires   Superconducting rotating machines   squirrel cage motors   large-scale applications   synchronous machines  

摘要： This work presents a simple and direct measurement method for rotor bar voltages in the rotating coordinate system of a high temperature superconducting induction/synchronous motor (HTS-ISM). The arrangement consists of soldering copper wires to the opposing ends of the rotor bars and routing them through a spinning reel to avoid entanglement, thereby providing a continuous electrical connection between the rotating quantities of the rotor and the stationary measurement instruments. Experiments with both ramped and stepped stator voltage inputs under no-load conditions revealed markedly different dynamic behaviors, including rapid acceleration, hunting torque, and current distortion. A recurring component at approximate to 1.05 Hz was consistently identified on the rotor bar voltages across independent tests, including at different input frequencies, suggesting the presence of an intrinsic oscillation under low excitation. The proposed measurement approach provides new experimental access to the flux-flow and synchronous regimes of HTS machines and establishes a foundation for future studies under load and with varied rotor designs.

关键词： Inductors   High-temperature superconductors   Superconducting transmission lines   Liquid nitrogen   Refrigeration   Shunts (electrical)   Heating systems   Reactive power   Electrical resistance measurement   Voltage measurement   HTS shunt reactors   type tests   dynamic balance state   AC loss  

摘要： With the rapid expansion of power system and the increasing level of underground-cable deployment in urban grids, the reactive power generated can no longer be absorbed locally during off-peak demand periods. This results in a reverse flow of reactive power, drives abnormal voltage rise, and poses a significant threat to grid stability and security. This paper presents a potential solution based on high-temperature superconducting (HTS) shunt reactor, and also provides a systematic introduction to the type tests of the 10 kV/1 MVar HTS reactor in Shanghai. First, the paper outlines the core structure and system composition of the device. Subsequently, it details the routine and special test items designed for the superconducting reactor, explains the unique temperature dynamic balance state of the superconducting reactor, and estimates the AC loss values of the superconducting reactor during actual operation. The results of this paper provides a solid foundation for the future in-field demonstration of superconducting reactors.