最新刊期
卷 63 ， 期 2 ， 2024
- 摘要：The Meso- and Neo-proterozoic geological records in eastern South China are the key carriers for understanding the Columbia and Rodinia supercontinent cycles and the geodynamic evolution of East Asia，which are yet uncertain so far. This paper presents an overview of key geological observations for the southwest Hainan，eastern Yangtze， and Cathaysia with respect to Proterozoic tectonics. Our data show that the SW Hainan in the Mesoproterozoic（~1.45 Ga）developed in a non-orogenic rift setting in the Columbia interior which was undergone by the ~1.05 Ga high-grade metamorphism. SW Hainan might be a part of the Mesoproterozoic Albany-Fraser Orogen at ~1.30-1.05 Ga，and，subsequently moved to the margin of Rodinia. Cathaysia and eastern Yangtze display distinct geological signatures in the early Neoproterozoic and Cathaysia remained separated from Yangtze until at least ~1.0 Ga，even ~0.83 Ga. The ~1.0-0.9 Ga felsic igneous rocks in Cathaysia are dominated by negative εHf（t） values，and distinct from those in the coeval Shuangxiwu arc with positive εHf（t）values. Such signatures might be the response to the subduction of the Proto-Ghats Ocean，herein named the Early Neoproterozoic Proto-Cathaysia Orogen. The ~870-830 Ma（mainly 850-830 Ma）igneous rocks are extensive in the Huaiyu and Jiangnan Orogen but poor in Cathaysia. The Cathaysia Neoproterozoic sedimentary rocks are signed by ~980 Ma detrital grains but dominated by ~860-830 Ma detrital zircons for the Jiangnan and Huaiyu sedimentary rocks. Banxi，Likou and Mamianshan groups and their equivalents are extensively developed in Cathaysia and Huaiyu，and the Jiangnan Orogen，respectively，and are characterized by the rift-related sedimentary rocks and bi-model igneous rocks with the formation ages of ~810-750 Ma. They are separated from the Cangshuipu and Luojiamen conglomerates across an angular unconformity or unconformably underlain by the Lengjiaxi and Xikou groups. In combination with the available data，it is proposed for a long-lived Neoproterozoic（~0.97-0.83 Ga）and westward-subducted Proto-Huanan arc-trench system signed by ~0.98-0.88 Ga Shuangxiwu intra-oceanic arc，0.87-0.83 Ga Huaiyu continental arc and 0.87-0.83 Ga Jiangnan intra-continental back-arc basin，which switched from an intra-oceanic to a continental Andean margin setting at ~0.87 Ga. Such a system lay along strike from the synchronous Eastern Ghats and South Delhi orogen at the periphery of Rodinia. Our data revealed the united proto-South China being created by the ~830-810 Ma Jiangnan orogenesis in response to the assemblage of the Yangtze with Cathaysia，which was followed by the post-orogenic rifting due to the breakup of Rodinia.关键词：Meso- and Neo-proterozoic geological records;Columbia interior;Rodinia periphery;Long-lived Proto-Huanan subduction;Yangtze-Cathaysia assemblage
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发布时间：2024-04-10
Invited article
- 摘要：Mount Danxiashan exhibits a significant red beds landform，which is formed of red sandstones and conglomerates. The exposed rock wall reflectance and regional area changes of Mt. Danxiashan （exposed characteristics） are affected by complex environmental factors. In this study， we quantified the reflectance of the red rock wall of Mt. Danxiashan through field measurements， extracted SWIR from Sentinel-2 satellite remote sensing data， and further identified the area changes of the exposed rock wall. Furthermore， we calculated the NDVI and collected the climate data from 2018 to 2022， aiming to discuss the spatio-temporal variations of characteristics of exposed palisades in Mt. Danxiashan in different scales by combining biotic environments and abiotic environments. Our results show that the reflectance of the exposed rock wall of Mt. Danxiashan is lower in the MAM and JJA， and higher in the SON and DJF， namely the brightness of the red beds is higher during these periods. The area of exposed rock wall varies little among the years from 2018 to 2022 but greatly among seasons， indicating that the exposed area is highest during the SON and DJF. The exposed features in Zhanglaofeng area are jointly affected by abiotic and biotic factors at different scales. The area changes of the exposed rock wall are mainly influenced by the climate-dominated growth of vegetation at a large scale. The color feature indicated by the reflectance of the exposed rock wall is mainly controlled by water and the surface biota at the micro-level.关键词：red beds;exposed characteristics;SWIR;biotic environment;abiotic environment;NDVI
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发布时间：2024-04-10 - 摘要：This study aims to investigate the effects of EnKF-based multi-source remote sensing soil moisture data assimilation on key elements of hydrological processes in the context of the Xiangjiang River Basin. SMAP and ASCAT remote sensing soil moisture data were selected for assimilation into the Distributed Hydrology Soil Vegetation Model (DHSVM) using the Ensemble Kalman Filter (EnKF) algorithm. By comparing and analyzing the simulated runoff and soil moisture results of three simulation scenarios: the non-assimilated model, ASCAT-DHSVM, and SMAP-DHSVM, the impact of multi-source remote sensing soil moisture data assimilation on hydrological variable simulation was evaluated. The results indicate that within the Xiangjiang River Basin, the ASCAT assimilation scheme outperforms the SMAP assimilation scheme in both streamflow simulation and soil moisture simulation. In terms of streamflow simulation, the ASCAT assimilation scheme exhibits an overall improvement in Nash-Sutcliffe Efficiency (NSE) (NSE=0.677) compared to the non-assimilation scheme (NSE=0.662), along with a decrease of 1.7 percentage points in BIAS. In terms of soil moisture simulation, compared to the non-assimilation scheme, the ASCAT assimilation scheme shows an overall improvement of 10% in NSE value, a decrease of 4.7 percentage points in BIAS, and a decrease of 12.5% in RMSE. In contrast, the improvement in the overall simulation performance of the SMAP assimilation scheme is statistically insignificant. The results underscore the efficacy of assimilating remote sensing soil moisture data, particularly through the ASCAT assimilation scheme, in enhancing hydrological variable simulation. These findings hold significant implications for water resource management in the Xiangjiang River Basin.关键词：DHSVM;Ensemble Kalman Filter;multi-source remote sensing data;soil moisture;data assimilation
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发布时间：2024-04-10 - 摘要：A large-scale heavy precipitation occurred in Jianghuai-South China from June 6 to 10，2022，causing severe floods and waterlogs. The precipitation mainly appeared near the shear line at 850 hPa. When the shear line moved to South China and coincided with the southwest warm and humid air，it resulted in a rainstorm in the region. In this paper，the performance of the China Meteorological Administration Global Forecast System （CMA-GFS） on this process is evaluated using ERA5 reanalysis and merging precipitation products. The diagnosis of forecast deviations and sensitivity experiments are also conducted. The results show that the movement of the South Asia high ridge，range of subtropical high，and the movement of the shear line at 850 hPa forecast by CMA-GFS that affect the location and shift of the rain belt are consistent with the results of ERA5 reanalysis. Therefore，the CMA-GFS performed well on the location and shift of this rain belt. However，the forecast has some deficiencies including that the precipitation along the shear line is weak，scattered heavy rainstorms in eastern Fujian，Northern Guangdong and central Guangxi are missed，the rain belt in northern Guangdong is located northward，and the magnitude of precipitation in warm sector is under estimated. The deviation diagnosis reflects that the wind speed forecast on the north side of the shear line is weaker by 3~8 m/s，and the water vapor convergence over the central and northern parts of Guangxi and Guangdong is weaker by 2×10-5~5×10-5 g/（m2·Pa·s），resulting in the weak precipitation on the shear line. The wind forecast on the south side is stronger by 3~5 m/s，resulting in the rain belt in northern Guangdong located northward by approximately 60 km. The jet over the South China coast at 850 hPa is weaker by 4~6 m/s，and the water vapor fluxes in the warm area are less by 4~10 g/（cm·hPa·s），resulting in the less rainstorms in the warm sector. Some numerical experiments are carried out to modify these deviations forecast by CMA-GFS. Using the analysis of the National Center for Environmental Prediction Global Forecast System to initialize the CMA-GFS significantly improves the forecast of rain belt location. Using the WSM6 microphysics scheme and tightening the trigger in the cumulus convective parameterization scheme improve the forecast of centers and magnitude of precipitation on the shear line，and the magnitude of the precipitation in the warm sector increases from small and moderate to moderate and heavy rain.关键词：CMA-GFS;heavy precipitation;deviation diagnosis;model improvement
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发布时间：2024-04-10 - 摘要：Problems of subgrade interlayer， ballast pockets， and mud pumping frequently occur under heavy-haul train loads， which seriously affect the safe operation of trains. To investigate the phenomenon of subgrade interlayer under heavy-haul train load， the cyclic loading tests of subgrade soil （silty clay） and ballast were carried out by a self-developed test apparatus， the deformation characteristics of the sample and the development of subgrade interlayer under the heavy-haul train load were analyzed. Furthermore， two characterizing indexes of subgrade interlayer， thickness of subgrade interlayer and migration quality of fine particles， were proposed. The results show that： 1） the axial deformation of the sample increases nonlinearly with the increase of loading times under heavy-haul load. The development of subgrade interlayer is obvious in the initial stage of loading， but not noticeable in the later stage of loading. 2） The thickness of the subgrade interlayer and the migration quality of fine particles can be used to characterize the features of the subgrade interlayer. The thickness of the subgrade interlayer and migration quality of fine particles are negatively correlated with the initial dry density of subgrade soil， and positively correlated with cyclic loading amplitude. The influence of loading frequency on the thickness of the subgrade interlayer and the migration quality of fine particles is relatively small.关键词：heavy-haul railway;subgrade interlayer;axial deformation;thickness of subgrade interlayer;migration quality of fine particles
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发布时间：2024-04-10 - 摘要：Drawing insights from the theories of path dependence and field-habitus，and taking the Chaoshan region，a high-incidence area of digestive tract cancers in Guangdong Province，as a case，this study attempts to understand why unhealthy local dietary behaviors have strong cultural inertia even in an era of scientific advancement. From the perspective of social and cultural mechanisms and using a mixed research method biding quantitative and qualitative approaches，the dietary traditions of Kong Fu tea and pickled food prevailing in the Chaoshan region，two dietary habits that are proven to be unhealthy and increase the occurrence risk of digestive tract cancers，are analyzed. Our study suggests （1） the pursuit of the aroma of Kong Fu tea by Chaoshan people，the traditional tea culture melt in daily life，and the social functions attached to Kong Fu tea have kept locking in and reinforcing the tasting manner of Kong Fu tea characterized by a hot drink with a high temperature；and （2） the traditional catering custom of raw pickled food，the need for fast and convenient food in a fast-paced modern society，and the pursuit of the seafood’s original and delicate flavor by local people have sustained the popularity of pickled food in the Chaoshan region. （3） In the dietary field of Chaoshan region，habitus is a socialized subjectivity with strong，unconscious，and structured power. It forms a social force shaping collective dietary behaviors，leading the social actors to slip into a natural and meaningful living space on their own. Existing studies of medical science and health geography tend to focus on the connections and links of physical environment，diseases，and dietary behaviors. This study，by revealing the social and cultural mechanisms underlying the path-dependent attributes of dietary habits，has contributed new insights to better understand these connections and links and provided new ways of thinking in the prevention of chronic diseases.关键词：digestive tract cancers;local dietary behaviors;path-dependence;field;habitus
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发布时间：2024-04-10 - 摘要：In recent years， three-dimensional （3D） reconstruction methods for complex disaster scenarios have attracted more and more attention， as the reconstruction of disaster scenarios can help rescuers rapidly cognize the extent of damage， locate victims， and plan the consequent tasks. To achieve rapid coverage and reconstruction of the chaotic disaster area， it is essential to plan optimized flying routes for UAVs. Based on the image acquisition and 3D reconstruction of the disaster area， this study focuses on the problem of path planning of UAVs. By establishing an a priori model via rapid air-camera sweeping of the UAV， the point cloud information is generated after evaluation， and the 3D viewpoint with position and direction constraints is generated. To meet the dynamic constraints of the UAV itself and the rotation constraints of the PTZ camera， the continuity of the path and the quality of the views are considered. Compared with Zig-Zag and circular paths， this study constructs a quick path planning method for 3D reconstruction of the disaster area.关键词：disaster rescue;3D reconstruction;path planning;UAV;sparrow search algorithm
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发布时间：2024-04-10 - 摘要：A model predictive control method based on Lyapunov function （LMPC） is proposed to control the specific orientation of non-cooperative spacecraft with orbit and attitude maneuvers. Firstly， according to the orbital dynamics equation in the line-of-sight coordinate system， the relative orbital dynamics model of the spacecraft satisfying the requirements of line-of-sight direction is established， and the analytical expression of the expected orbit is derived. Secondly， the MPC method is used to design the controller for online optimization control， and the contraction constraint formula is constructed to ensure the closed-loop stability by incorporating the display features of the nonlinear backstepping control based on the Lyapunov method. Then， the recursive feasibility and closed-loop stability of LMPC based control method are proved. Finally， the simulation results prove the effectiveness and robustness of the proposed LMPC trajectory tracking method.关键词：non-cooperative target;close line of sight;nonlinear dynamic system;control Lyapunov function;model predictive control
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发布时间：2024-04-10 - 摘要：The mechanical properties of heat pipe-cooled reactor which is a preferred core for nuclear reactor batteries at high temperatures needs attention. Taking MegaPower as the object, a thermal-mechanical coupling calculation of the reactor under full power operation condition is carried out using the open source Monte Carlo program (OpenMC) and ANSYS mechanical. The results show: (1) The core monolith generates significant temperature and thermal stress concentration, with peak temperatures of 1 023 K for the fuel and 970 K for the monolith, and the highest thermal stress of 49.5 MPa for the monolith; (2) Because of the effect of high-temperature creep, the stress in the monolith decreases significantly, and the stress distribution tends to be uniform. (3) During the core operation, the total equivalent strain of the monolith changes slightly, while the reduction of the equivalent elastic strain and the increase of the equivalent creep strain is almost simultaneous and equal.关键词：solid-state reactor core;high temperature;316H stainless steel;creep
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发布时间：2024-04-10 - 摘要：A two-scale digital image correlation method based on flexible curved arch is proposed in this paper. In integer pixel scale， the initial estimation of deformation parameters at pixel level is quickly found by Fourier transform. In sub-pixel scale， combined with pixel level initial estimation and inverse synthesis Gaussian-Newton iteration， the deformation measurement results with sub-pixel precision is obtained. After the vibration response of the structure is obtained， the natural frequency and mode of the structure are identified by frequency domain decomposition method. Finally， the visual measurement experiment was conducted on a flexible curved arch， supplemented by comparative analysis of laser vibration measurement， to verify the effectiveness of the proposed method in vibration measurement and modal identification of flexible structures.关键词：digital image correlation;two-scale displacement recovery;flexible and large deformation structure;modal identification
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发布时间：2024-04-10 - 摘要：For the environmental monitoring of marine ranching， a 3D underwater wireless sensor networks coverage method based on improved Dung beetle optimizer （IDBO） is proposed. Firstly， Chebyshev chaotic mapping was added to the DBO population initialization to make population resources more balanced in the allocation of search space. Secondly， adaptive weight factor and Levy flight were used to improve the position update mode of Dung beetles， which improved the position search ability and the convergence ability of DBO algorithm. The IDBO algorithm was applied to the UWSN coverage optimization of marine ranching，the simulation results show that the coverage rate of IDBO algorithm is higher than that of random deployment and other intelligent optimization algorithms under different parameter environments， and it achieves higher coverage rate with lower node energy consumption， and the distribution of nodes is more reasonable.关键词：marine ranching;UWSN;Chebyshev chaotic mapping;adaptive weight factor;Levy flight
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发布时间：2024-04-10 - 摘要：A method for calibration of the in-orbit center-of-mass offset only on accelerometer data is proposed in order to address the issue of calibration of the in-orbit center-of-mass offset of gravity satellite. With ACC1A data as input， and the Butterworth filter is utilized to remove noise from the data. The linear acceleration and angular acceleration signals caused by the calibration maneuver of center-of-mass are extracted， and finally， the center-of-mass offset is calibrated using the least squares estimation. The method for calibration of the in-orbit center-of-mass proposed in this paper is validated using the accelerometer data from the GRACE-FO C satellite， and the center-of-mass offset since the satellite's launch is estimated. The results show that the calibration accuracy of all three axes is better than 10 μm. The RMS differences in the comparison of the center-of-mass offset results in the three-axis direction， obtained by using the proposed method and by calculating with attitude data， are respectively ［9.6，9.3，7］ μm， and the RMS of comparison with the center-of-mass offset published by JPL are respectively ［7.4，3.8］ μm. Different from the traditional method， because only accelerometer data is used， the proposed method can be used for calibration of the in-orbit center-of-mass in the case of data failure of gyroscope and star camera.关键词：GRACE-FO;gravity satellite;accelerometer;center-of-mass calibration
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发布时间：2024-04-10 - 摘要：TMEM138 is a ciliary protein. Absence of TMEM138 can cause phylogenetic ciliopathy-Joubert syndrome. In order to analyze the molecular mechanism of TMEM138， the conservative analysis and topological structure of TMEM138 were studied. Eight representative species were selected to analyze the conserved primary， secondary and tertiary structure of TMEM138 protein， and determined that the transmembrane domain of TMEM138 is the most conserved， which is an important structural basis for realizing its function. By constructing the in vitro overexpression vector of TMEM138 and combining with the live cell staining technique， we verified the membrane localization and topological structure of TMEM138 for the first time. This conclusion can provide further help for the study of TMEM138.关键词：TMEM138;conservation analysis;membrane topology
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发布时间：2024-04-10 -
Integrin β3 promotes metastasis of nasopharyngeal carcinoma cells by activating the MAPK/ERK pathway
摘要：Nasopharyngeal carcinoma (NPC) is a prevalent head and neck malignancy in South China and Southeast Asia, often leading to treatment failure due to distal metastasis and local recurrence. This study showed a significant increase in the expression of integrin β3 (ITGB3) in highly metastatic NPC cells compared to poorly metastatic NPC cells. This study further elucidates that upregulation of ITGB3 expression not only enhances the migratory, invasive, clonogenic, and adhesive capacities of NPC cells, but also promotes their proliferation and inhibiting apoptosis. Mechanistically, ITGB3 primarily activates the MAPK/ERK pathway, as a result, enhancing the migratory, invasive, clonogenic, and adhesive capabilities of NPC cells. These findings in the study reveal the regulatory effect and molecular mechanism of ITGB3 on NPC cell metastasis, providing a new theoretical basis for the prevention and treatment of NPC cell metastasis.关键词：nasopharyngeal carcinoma;integrin β3;tumor metastasis;MAPK/ERK pathway- 34
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发布时间：2024-04-10 - 摘要：In order to obtain a plant growth-promoting rhizobacteria with dual effects of medicine and fertilizer，a bacteria strain，named as F13， which has the function of dissolving phosphorus and potassium， was isolated from the grape rhizosphere soil. The bacterium was identified as Pseudomonas aeruginosa by morphological observation， physiology and biochemistry and 16S rDNA identification. The plate confrontation method determined that the fermentation broth of strain F13 had an antagonistic effect on 8 kinds of plant pathogens， and the antibacterial rate was between 63.26% and 81.53%. In the field application， it was found that the root irrigation of the strain F13 had a significant effect on the growth of cowpea. The experimental group was 26.7%， 24.4%， and 11.9%， respectively， higher than that of the control group in terms of plant height， number of leaves， and stem diameter， and the yield increased by 39.68%. Compared with the control group， the experimental group increased phosphorus and potassium by 11.5% and 46.8%， and increased vitamin C and soluble protein content by 22.15% and 55.55%， respectively. In addition， strain F13 had a good control effect on cowpea powdery mildew， and the control efficacy in field reached 71.92%. Therefore， strain F13 is a rhizosphere growth-promoting bacterium with great potential for application of medicine and fertilizer.关键词：plant growth-promoting rhizobacteria;promoting effect;antagonistic action
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发布时间：2024-04-10 - 摘要：The metabolites of the endophytic fungus Talaromyces amestolkiae 30 from the mangrove plant Aegiceras corniculatum (L.) Blanco were investigated. The fungus was cultured in rice medium, the monomeric compounds were isolated and purified by the chromatographic technique, and the structures of the compounds were identified by analysis of spectroscopy such as ESIMS and NMR. Twelve known analogues of isocoumarins (1-12) were isolated and identified as aspergillumarin A (1), aspergillumarin B (2), 5,6-dihydroxy-3-(4-hydroxypentyl)-isochroman-1-one (3), mucorisocoumarin A (4), peniisocoumarin H (5), peniisocoumarin E (6), dichlorodiaportin (7), mucorisocoumarin C (8), peniisocoumarin G (9), talumarin A (10), 5,6,8-trihydroxy-4-(1'-hydroxyethyl)-isocoumarin (11) and sescandelin (12). Among them, compounds 4, 6 and 7 were obtained from the genus Talaromyces for the first time. The antibacterial activities of these compounds were tested in vitro using the twofold dilution method. Compounds 4, 6, and 7 showed inhibitory activity against Staphylococcus aureus. The cytotoxic activity was tested by the MTT assay. Compound 7 showed cytotoxicity against prostate cancer PC-3 cells and VCaP cells.关键词：mangrove fungus;Talaromyces amestolkiae;secondary metabolites;isocoumarin
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发布时间：2024-04-10 - 摘要：The title reaction was performed using the M06-2X and MN15 methods of DFT combined with the Slovation Model Density （SMD） model method based on self-consistent reaction field theory. The results showed that, His molecule can be transferred when the carbonyl O atom as the only bridge of α-H proton, and α-H transfers with amino group N and carbonyl O atom as bridges after the proton of protonated amino group N transfers to carbonyl O atom，respectively；Also, α-H achieves enantiotropy in five channels using amino group N and carbonyl group O as bridges after the proton transfers from the protonated amino group N to the N of the imidazole ring，respectively. Investigation on the potential energy surface showed that the free energy barriers of rate-determining step for each of the five channels are 245.6， 238.1， 297.3， 270.9 and 257.7 kJ/mol under the effect of recessive solvent； the energy barriers are reduced to about 139.9，120.7，161.7，142.7 and 157.3 kJ/mol under the effect of dominant solvent. The results show that His can racemize with a small amount in the water-liquid environment， and it is relatively safe to be used to supply His for life.关键词：histidine;enantiotropy;density functional theory;transition state;Gibbs free energy
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发布时间：2024-04-10
Research articles
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