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Study region: Lop Nur, Xinjiang Province, China Study focus: Lop Nur has been a vast playa which was a historic lake in eastern Tarim Basin, northwest China. The lake's catchment played a significant role in the development of oasis states in the early Common Era, such as the ancient Loulan Kingdom. However, the history of lake dynamics remains unclear, and its potential linkage to the decline of Loulan Kingdom has been not well-examined. This paper aims to reconstruct the lake-level changes in Lop Nur over the last 2000 years using synthetic aperture radar (SAR) data, optically stimulated luminescence (OSL) dating of lacustrine and aeolian sediments, and radiocarbon (14C) dating of ancient bio-remains. Furthermore, the relationships between Lop Nur' fluctuation and the decline of ancient Loulan Kingdom were discussed New hydrological insights for the region: The results suggest that Lop Nur once covered an area more than 11, 602 km2 and that lake-level reduced gradually during 360–470 C.E. Subsequently, the lake experienced a few stages of lake-level fluctuation which never reached the upper-most shorelines. Also, the historical changes in the lake level were temporal coincided with the ancient Loulan Kingdom's collapse, showing that the dynamics of hydrological conditions in catchment may have a direct influence on the fall of human settlement in drylands.

Synthetic aperture radar (SAR) is an effective and important technique in monitoring crop and other agricultural targets because its quality does not depend on weather conditions. SAR is sensitive to the geometrical structures and dielectric properties of the targets and has a certain penetration ability to some agricultural targets. The capabilities of SAR for agriculture applications can be organized into three main categories: crop identification and crop planting area statistics, crop and cropland parameter extraction, and crop yield estimation. According to the above concepts, this paper systematically analyses the recent progresses, existing problems and future directions in SAR agricultural remote sensing. In recent years, with the remarkable progresses in SAR remote sensing systems, the available SAR data sources have been greatly enriched. The accuracies of the crop classification and parameter extraction by SAR data have been improved progressively. But the development of modern agriculture has put forwarded higher requirements for SAR remote sensing. For instance, the spatial resolution and revisiting cycle of the SAR sensors, the accuracy of crop classification, the whole phenological period monitoring of crop growth status, the soil moisture inversion under the condition of high vegetation coverage, the integrations of SAR remote sensing retrieval information with hydrological models and/or crop growth models, and so on, still need to be improved. In the future, the joint use of optical and SAR remote sensing data, the application of multi-band multi-dimensional SAR, the precise and high efficient modeling of electromagnetic scattering and parameter extraction of crop and farmland composite scene, the development of light and small SAR systems like those onboard unmanned aerial vehicles and their applications will be active research areas in agriculture remote sensing. This paper concludes that SAR remote sensing has great potential and will play a more significant role in the various fields of agricultural remote sensing.

The accuracy of dryland crop classification using satellite-based synthetic aperture radar (SAR) data is often unsatisfactory owing to the similar dielectric properties that exist between the crops and their surroundings. The main objective of this study was to improve the accuracy of dryland crop (maize and cotton) classification by combining multitype features and multitemporal polarimetric SAR (PolSAR) images in Hebei plain, China. Three quad-polarimetric RADARSAT-2 scenes were acquired between July and September 2018, from which 117 features were extracted using the Cloude–Pottier, Freeman–Durden, Yamaguchi, and multiple-component polarization decomposition methods, together with two polarization matrices (i.e., the coherency matrix and the covariance matrix). Random forest (RF) and support vector machine (SVM) algorithms were used for classification of dryland crops and other land-cover types in this study. The accuracy of dryland crop classification using various single features and their combinations was compared for different imagery acquisition dates, and the performance of the two algorithms was evaluated quantitatively. The importance of all investigated features was assessed using the RF algorithm to optimize the features used and the imagery acquisition date for dryland crop classification. Results showed that the accuracy of dryland crop classification increases with evolution of the phenological period. In comparison with SVM, the RF algorithm showed better performance for dryland crop classification when using full polarimetric RADARSAT-2 data. Dryland crop classification accuracy was not improved substantially when using only backscattering intensity features or polarization decomposition parameters extracted from a single-date image. Satisfactory classification accuracy was achieved using 11 optimized features (derived from the Cloude–Pottier decomposition and the coherency matrix) from 2 RADARSAT-2 images (acquisition dates corresponding to the middle and late stages of dryland crop growth). This study provides an important reference for timely and accurate classification of dryland crop in Hebei plain, China.

We present a classification of plastic-mulched farmland (PMF) and other land cover types using full polarimetric RADARSAT-2 data and dual polarimetric (HH, VV) TerraSAR-X data, acquired from a test site in Hebei, China, where the main land covers include PMF, bare soil, winter wheat, urban areas and water. The main objectives were to evaluate the outcome of using high-resolution TerraSAR-X data for classifying PMF and other land covers and to compare classification accuracies based on different synthetic aperture radar bands and polarization parameters. Initially, different polarimetric indices were calculated, while polarimetric decomposition methods were used to obtain the polarimetric decomposition components. Using these polarimetric components as input, the random forest supervised classification algorithm was applied in the classification experiments. Our results show that in this study full-polarimetric RADARSAT-2 data produced the most accurate overall classification (94.81%), indicating that full polarization is vital to distinguishing PMF from other land cover types. Dual polarimetric data had similar levels of classification error for PMF and bare soil, yielding mapping accuracies of 53.28% and 59.48% (TerraSAR-X), and 59.56% and 57.1% (RADARSAT-2), respectively. We found that Shannon entropy made the greatest contribution to accuracy in all three experiments, suggesting that it has great potential to improve agricultural land use classifications based on remote sensing.

The object of the present study was to investigate the yield-affecting mechanisms influenced by N and P applications in rainfed areas with calcareous soil. The experimental treatments were as follows: NF (no fertilizer), N (nitrogen), P (phosphorus), and NP (nitrogen plus phosphorus) in a field pea-spring wheat-potato cropping system. This study was conducted over six years (2003-2008) on China’s semi-arid Loess Plateau. The fertilizer treatments were found to decrease the soil water content more than the NF treatment in each of the growing seasons. The annual average yields of the field pea crops during the entire experimental period were 635, 677, 858, and 1117 kg/ha for the NF, N, P, and NP treatments, respectively. The annual average yields were 673, 547, 966, and 1056 kg/ha for the spring wheat crops for the NF, N, P, and NP treatments, respectively. Also, the annual average yields were 1476, 2120, 1480, and 2424 kg/ha for the potato crops for the NF, N, P, and NP treatments, respectively. In the second cycle of the three-year rotation, the pea and spring wheat yields in the P treatment were 1.2 and 2.8 times higher than that in the N treatment, respectively. Meanwhile, the potato crop yield in the N treatment was 3.1 times higher than that in the P treatment. In conclusion, the P fertilizer was found to increase the yields of the field pea and wheat crops, and the N fertilizer increased the potato crop yield in rainfed areas with calcareous soil.

Using unmanned aerial vehicles (UAVs) for performing automatic inspection of overhead power lines instead of foot patrols is an attractive option, since doing so is safer and have considerable cost savings, among other advantages. The purpose of this paper is to design a 3D laboratory test-platform to simulate UAVs' inspection of transmission lines and secondly, proposing an automated inspection strategy for UAVs in order to follow transmission lines. The construction and system architecture of our 3D test-platform is described in this paper. The inspection strategy contributes to knowledge pertaining to an automated inspection procedure and includes two steps: flight path planning for UAVs and visual tracking of the transmission lines. The 3D laboratory test-platform is applied to test the performance of the proposed strategy and the tracking results of our inspection strategy are subsequently presented. The availability of the 3D laboratory test-platform and the efficiency of our tracking algorithm are verified by experiments.

During CO2 transportation and storage, metal equipment such as oilfield pipelines suffers from severe CO2 corrosion, especially in harsh downhole injection equipment. In this study, we investigated the corrosion behavior of oil well tubing in a high-temperature, high-pressure (HTHP) CO2-containing environment. The evolution of the corrosion scale was also examined under different flow regimes. The results reveal a lower corrosion rate at 150 °C compared to 80 °C under different flow regimes, with localized corrosion intensifying as temperature and rotational speeds (vrs) increase. The temperature also induces the corrosion scale conversion of aragonite-type CaCO3 (80 °C) to calcite-type CaCO3 (150 °C). Specifically, the variation of the corrosion rate and the corrosion scale evolution can be attributed to the vortices within the reactor. The intact vortex cells enhance mass transfer while also promoting nucleation and growth of CaCO3. However, when vrs exceeds the critical Reynolds number, the vortex cells are disrupted, resulting in viscous dissipation and a reduced corrosion rate. [ABSTRACT FROM AUTHOR]

Background: Simiaowan (SMW), a well-known traditional Chinese medicine, has beenemployed to treat hyperuricemia (HUA) and gout for centuries. However, the bio active components and underlying mechanisms have not been elucidated. The objective of thisstudy was to identify the active components and potential mechanisms of SMW by integrating pharmacological experimentation, serum pharmacochemistry, network pharmacology and molecular docking. Methods: HUA rats modelling by high-fat/high-sugar diet and potassium oxonate/adenine oral administration were usedtoevaluate the pharmacodynamic effects of SMW. UPLC-Q-Exactive-MS/MS was employed to detect the bioactive components present in SMW-containing serum. Network pharmacology and molecular docking were utilized to elucidate the potential targets and underlying mechanisms. Results: SMW effectively ameliorated HUA rats via the inhibitionof uric acid (UA) production, promotion of UA excretion, improvement of lipid and glucose metabolic abnormalities, antioxidant, anti-inflammatory and anti-insulinresistance effects. A total of 73 compounds detected in SMW-containing serum were identified as potential active components, with alkaloids, flavonoids, organic acids, and terpenoids emerging as the primary active ingredients. Totally 203 corresponding targets were obtained as SMW anti-HUA/gout targets, which mainly participated in apoptosis, insulin resistance, TNF, PI3K-Akt, HIF-1, NF-κB, MAPK, IL-17 and TLR signaling pathways. Molecular docking indicated that active compounds (e.g. berberine, phellodendrine, quercetin, formononetin, ferulic acid) had superior binding abilities to the key targets (e.g. solute carrier family 22 member 12 (URAT1), solute carrier family 22 member 6 (OAT1), ATP-binding cassette sub-family G member 2 (ABCG2), solute carrier family 2, facilitatedglucose transporter member 9 (GLUT9), xanthine dehydrogenase/oxidase (XDH), transcription factor p65 (RELA), toll-like receptor 4 (TLR4), prostaglandin G/Hsynthase2(PTGS2), caspase-3 (CASP3), insulin (INS)). Conclusion: SMWexerted regulatoryinfluence over the disease network of HUA and gout through a multiplicity of components, targets, and pathways. Alkaloids, flavonoids, organic acids, and terpenoids weretheprimary active components, exerting anti-HUA/gout effects via antioxidant, anti-inflammatory, anti-insulin resistance, anti-apoptosis, inhibition of UA production, and promotion of UA excretion. This study revealed the active components and molecular mechanisms of SMW, providing insights into the development of natural products derived from SMW. [ABSTRACT FROM AUTHOR]

Millions of microorganisms make up the complex microbial ecosystem found in the human gut. The immune system's interaction with the gut microbiota is essential for preventing inflammation and maintaining intestinal homeostasis. Numerous metabolic products that can cross-talk between immune cells and the gut epithelium are metabolized by the gut microbiota. Traumatic injury elicits a great and multifaceted immune response in the minutes after the initial offense, containing simultaneous pro- and anti-inflammatory responses. The development of innovative therapies that improve patient outcomes depends on the gut microbiota and immunological responses to trauma. The altered makeup of gut microbes, or gut dysbiosis, can also dysregulate immunological responses, resulting in inflammation. Major human diseases may become more common as a result of chronic dysbiosis and the translocation of bacteria and the products of their metabolism beyond the mucosal barrier. In this review, we briefly summarize the interactions between the gut microbiota and the immune system and human disease and their therapeutic probiotic formulations. We also discuss the immune response to traumatic injury. [ABSTRACT FROM AUTHOR]

Equipment used in underwater sensing and exploration typically relies on cables or batteries for energy supply, resulting in a limited and inconvenient energy supply and marine environmental pollution that hinder the sustainable development of distributed ocean sensing networks. Here, we design a deep-sea differential-pressure triboelectric nanogenerator (DP-TENG) based on a spiral shaft drive using modified polymer materials to harness the hydrostatic pressure gradient energy at varying ocean depths to power underwater equipment. The spiral shaft structure converts a single compression into multiple rotations of the TENG rotor, achieving efficient conversion of differential pressure energy. The multi-pair electrode design enables the DP-TENG to generate a peak current of 61.7 μA, the instantaneous current density can reach 0.69 μA cm-2, and the output performance can be improved by optimizing the spiral angle of the shaft. The DP-TENG can charge a 33 μF capacitor to 17.5 V within five working cycles. It can also power a digital calculator and light up 116 commercial power light-emitting diodes, demonstrating excellent output capability. With its simple structure, low production cost, and small form factor, the DP-TENG can be seamlessly integrated with underwater vehicles. The results hold broad prospects for underwater blue energy harvesting and are expected to contribute to the development of self-powered equipment toward emerging “smart ocean” and blue economy applications. [ABSTRACT FROM AUTHOR]

The article discusses the replacement of a sexual Artemia species by an obligate parthenogenetic lineage in a natural salt lake in China. Through various analyses, it was determined that the population in the lake belongs to a parthenogenetic lineage with a ploidy level of 2n. The study highlights the impact of climate change on hypersaline ecosystems and the rare occurrence of such replacements in the natural world. [Extracted from the article]