最新刊期
期 6 ， 2023
- 摘要：The Cambrian Explosion represents an important geological period in which major metazoan phyla appeared abruptly and the Earth’s ecosystems underwent a significant shift. Since then, the marine ecosystem on Earth has transitioned from a 2-trophic-level ecosystem during Precambrian to a 3-trophic-level ecosystem driven by animal consumption. This transition has become a key area of research for understanding the early evolution of the Earth habitability during the Phanerozoic Eon. The Cambrian Explosion is also marked by the sudden and rapid appearance of abundant bilateral animals with mineralized shells in the marine ecosystem. These cap-shaped and tubular shell fossils mostly belong to lophotrochozoans with uncertain biological affinities. Therefore, the origin and phylogenetic evolution of early Cambrian lophotrochozoans, especially those in the early Cambrian, are of highly debated topics in paleobiology and even modern evolutionary biology. Brachiopods are an important group of lophotrochozoans with rich fossil occurrences through the entire Phanerozoic. They constitute a major component of the Cambrian evolutionary fauna, and thus have significant implications for our understanding of paleoecology, paleogeography, and macroevolution of animals on Earth. As for the origin of Cambrian brachiopods, the Brachiopoda Fold Hypothesis (i.e. Halkieria model), phoronid-like animal hypothesis, tommotiids’origin story, and the agglutinated tubular lophophorate hypothesis are proposed, and await further testing by additional fossils. This paper focuses on the origin of Cambrian brachiopods, systematically discusses various hypotheses and comprehensively summarizes recent discoveries in fossils, as well as explores the significant implications of the discovery of the earliest entoprocts, cage worms, and segmented Wiwaxia, as well as the agglutinated Yuganotheca elegan for understanding the origin of brachiopods and their phylogenetic relationships and evolution within lophotrochozoans. Nevertheless, many questions regarding the issues on the brachiopods’ origins and Cambrian Explosion are yet to be resolved. Therefore, it is crucial to integrate multiple preservation types of fossil lophotrochozoans, collected from various types of depositional environments (exceptional preservation in shales and small shelly fossils in carbonates), so as to conduct comprehensive and comparative studies of the anatomies of soft bodied fossils and their relative biomineralized shell valves. These comparative studies will play a key role in tracing the origin of brachiopods and their phylogenetic relationship with other lophotrochozoans within all the metazoans.关键词：brachiopods;lophotrochozoan;phylogenetics;biomineralization;Cambrian Explosion
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发布时间：2024-01-03 - 摘要：The research object of paleontology is " dead" fossils. How to display dead fossils to the public in the " living" form has always been one of the difficulties and hotspots in paleontology research. Paleo-bioinformaticsis a new concept which was proposed by Prof. Jianni Liu in 2012. Paleo-bioinformatics is a multidisciplinary cross-fertilization of paleontology, informatics, mathematics, biology and art, which not only strives to scientifically and aesthetically display the evolutionary relationship between fossils or between fossils and living organisms, but also helps to restore and 3D reconstruct of fossils based on their characters. This paper introduces the development history and construction results of the electronic platform for paleontological fossil resources, sorts out the research content of palaeontological pedigree analysis methods, expounds the research results of paleontological fossil images retrieval and three-dimensional reconstruction, and demonstrates the research and development of paleontological information visualization technology and related popular science products. Finally, the development prospect of Paleo-bioinformatics is forecasted, which will be one of the core fields of natural science in the 21st century.关键词：paleo-bioinformatics;palaeontological fossil resources platform;palaeontological pedigree analysis;fossil image retrieval;three-dimensional reconstruction of fossils
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发布时间：2024-01-03 - 摘要：Comprehensive analysis of the structural characteristics and the possible faults by integrating gravity, magnetic, electrical, and remote sensing data; for areas far away from faults, based on comprehensive analysis of drilling and logging data, fine lithology identification, reservoir physical properties and cap rock characteristics is used to clarify the characteristics of high quality reservoirs-cap rock combinations and spatial distribution; based on the simulation results of CO2 injectability experiments, a sequence of optimization techniques about the site selection for the CO2 geological storage of sweet spots is formed.Thus, the goal to optimize the site for CO2 geological storage of sweet spots in the saline aquifers is achieved. Research shows, the third member of the Zhifang Formation, the 5th member of the Shiqianfeng Formation in the area of Shenmu and the Chang 10 Member of Yangchang Formation in the northern and northwestern regions of Yulin have well-developed sand bodies with good physical properties, excellent caprock and lateral shielding conditions, far away from the faults, with burial depth of 750~1 500 m, 1 500~2 100 m, and 850~1 350 m. Research suggests that the development area of high-quality reservoirs in the third member of the Zhifang Formation and the 5th member of the Shiqianfeng Formation are the favorable potential sweet spot distribution areas for the CO2 geological storage in the saline aquifers, and the development area of high-quality reservoirs at the bottom of Chang10 in the northern and northwestern regions of Yulin is a potential replacement sweet spot distribution area for the CO2 geological storage in the saline aquifers; in the study area, the sand bodies of the Heshanggou Formation and Liujiagou Formation are relatively underdeveloped and mainly composed of mud strata, which play a good sealing role.关键词：saline aquifers;CO2 geological storage;well log;reservoir-caprock assemblage;sweet spot;site selection
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发布时间：2024-01-03 - 摘要：The different trapping mechanisms of the CO2 saline aquifers geological storage process were outlined and the storage capacity calculation methods of different CO2 trapping mechanisms were summarized. Based on the investigation and analysis on CO2 saline aquifer geological storage projects and numerical simulation, the application scope of the calculation method for different CO2 trapping mechanisms in saline aquifers is analyzed. After comprehensive analysis, the volumetric method can be applied to the calculation of CO2 structural trapping storage capacity of geological units of different scales in the geological evaluation stage. It represents the maximum storage potential of the evaluation unit. Based on the selection of reasonable engineering, economic and other parameters, volumetric method can be updated. Calculation of high potential level storage volumes. Based on the selection of reasonable engineering, economic and other parameters, it can calculate the higher-level storage capacity. The application scope of long-time scale storge capacity calculation, including the residual, solubility, and mineral trapping, is the actual storage capacity at a certain time or time period at the site level or perfusion level, which only be obtained by establishing a geological model based on a defined storage project or storage site and by numerical simulation over a long-time scale.关键词：CO2 geological storage;saline aquifers;CO2 trapping mechanism;storage capacity calculation;application scope
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发布时间：2024-01-03 - 摘要：Soils and various sediments are the most common materials in archaeological excavations. They are not only the matrix for various archaeological remains, but also objects of archaeological research themselves, containing abundant archaeological information. With the rapid development of archaeological research methods and detection techniques, the scope of archaeological research continues to expand from the macro level to the micro level at the molecular scale. Archaeological research on soils and sediments has also become increasingly refined. However, current archaeological soil research still remains at the macro level, while micro-level research is still in its infancy. To achieve the leap from macro to micro, this study systematically reviews four aspects of microscopic archaeological soil research: soil geochemistry, soil micromorphology, sediment ancient DNA and organic residue analysis. The study shows that: ①soil geochemistry uses elemental anomaly distributions to infer human activities, and has been applied to site surveying and functional area delineation; ②soil micromorphology reveals the influence of natural and anthropogenic factors on soils, and can be used for environmental archaeology research; ③sediment ancient DNA enables identification of ancient biological species, which has been widely applied to ancient environmental research; ④organic residueanalysis can detect remnants of ancient diet, rituals and other activities, providing evidence for reconstructing ancient production and living. In summary, the four parts above mentioned play important roles in microscopic archaeological soil research, but have not yet formed a system. This study suggests that archaeological soil microscopic research should strengthen multiproxy comprehensive research, explore unified soil preservation methods, so as to promote the transition of archaeological soil research from macro to micro, for excavating more abundant archaeological information.关键词：archaeological soil;geochemical analysis;soil micromorphology;sediment ancient DNA;organic residue analysis
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发布时间：2024-01-03 - 摘要：Image inpainting is a process that involves utilizing computer algorithms and image processing techniques to restore damaged, missing, or corrupted regions within an image. The objective of this process is to generate visually reasonable and coherent structures and textures in the repaired regions, while simultaneously being as consistent as possible with the appearance of the original image. Traditional image inpainting techniques predominantly rely on rule-based and heuristic methods, utilizing low-level features such as local pixel relationships, edge information, and texture statistics to perform inpainting tasks. However, handling images with intricate semantics through these methods has proven challenging. In recent years, the prominence of deep learning technology has grown significantly in image inpainting tasks owing to its powerful feature extraction capabilities. By leveraging large-scale datasets, these methods automatically learn high-level features and complex semantic information of images through deep convolutional neural networks or generative adversarial networks. However, there are few existing summary studies on image inpainting, while the evolution of deep learning technology is progressing rapidly. In order to facilitate the effective application and development of deep learning methods in image inpainting, a systematic categorization and summary of existing techniques is imperative. This article provides a systematic review and comprehensive overview of deep learning-based image restoration methods, offering a systematic summary of image inpainting methods from the perspective of inpainting strategies. We specifically analyzed the strengths and limitations of each method category, summarized commonly used datasets, quantitative evaluation metrics, and performance comparisons of representative approaches. Ultimately, we discussed the existing challenges in the field of image inpainting and proposed potential research avenues for future investigations.关键词：digital image processing;image inpainting;deep learning;computer vision
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发布时间：2024-01-03 - 摘要：The objective of liver tumor segmentation is to pinpoint the region containing the liver tumor, aiding medical professionals in delivering precise diagnosis and treatment. Owing to its capacity to automatically learn intricate features and structures from medical images, deep learning has emerged as one of the mainstream approaches to liver tumor segmentation. Nonetheless, the size, shape, and blurred edges of liver tumor exhibit significant variations, which constrain the segmentation performance of deep learning models. Consequently, we introduce a deep network that incorporates multi-scale features and a reverse attention mechanism for the automatic segmentation of liver tumor. Specifically, drawing upon the U-Net model framework, this study designs a multi-scale feature extraction module and a reverse attention module based on deep supervision. This enables the network to adaptively select features of varying scales according to the size of the segmented target and direct the network’s attention towards the edge features of the segmented object, thereby enhancing the network’s edge segmentation capability. Furthermore, a novel hybrid loss is devised to address the issue of class imbalance in medical image segmentation.The recent numerical experiments conducted on the MICCAI2017 LiTS Challenge dataset have demonstrated that the proposed method achieves a Dice coefficient of 76.12% and an average symmetric surface distance (ASSD) of 3.25 mm.关键词：liver tumor segmentation;multi-scale feature extraction;reverse attention
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发布时间：2024-01-03 - 摘要：Due to the influence of climate change and human activities, evapotranspiration and its components have changed significantly in the Loess Plateau, which has affected the hydrological process and sustainable utilization of water resources in the basin. Based on multivariate data fusion, trend analysis and multiple regression residual analysis are used to analyze the characteristics of evapotranspiration and its components in the Loess Plateau from 2001 to 2020 and their response mechanism to climate change and human activities. The average annual increase of evapotranspiration on the Loess Plateau from 2001 to 2020 was 2.869 4 mm (R2=0.384 6), and the main factors affecting the change were non-vegetation underlying surface, saturated water vapor pressure and rainfall, with the contribution rates of 23.47%, 21.31% and 12.22%, respectively.Vegetation transpiration showed an increasing trend and its proportion increased, with an annual growth rate of 3.716 5 mm/a (R2=0.527 1). The main factors affecting its change were non-vegetation underlying surface, saturated water vapor pressure and vegetation, and the contribution rates were 22.13%, 19.43% and 15.86%. The interception loss also showed a significant increase trend, increasing by 0.354 mm (R2=0.694 6) per year, and its proportion increased. The main factors affecting its change were non-vegetation underlying surface, vegetation and saturated water vapor pressure, and the contribution rates were 22.24%, 13.85% and 12.47%soil evaporation decreased by 1.405 4 mm (R2=0.741 5) year by year, and its proportion decreased. The main factors affecting its change were non-vegetation underlying surface, vegetation and saturated water vapor pressure, and the contribution rates were 28.29%, 19.15% and 13.66%.In conclusion, climate change is still the most important factor affecting evapotranspiration and its components on the Loess Plateau, and saturated water vapor pressure is the biggest meteorological factor, the role of vegetation change and non-vegetation underlying surface factors can not be ignored.This study can provide theoretical basis for scientific understanding of evapotranspiration change mechanism and promoting sustainable utilization and management of water resources on the Loess Plateau.关键词：climate change;Human activities;evapotranspiration;residual analysis;Loess Plateau
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发布时间：2024-01-03 - 摘要：This paper mainly discusses the theories and methods with the interpretability research perspective. Firstly, we illuminate the evolutionary process on three generations of rough set models, and clarify the development track of three-way decision. Secondly, we focus on the deep integration between three-way decision and granular computing, and introduce the corresponding theories and methods of sequential three-way decision and hierarchical three-way decision. Thirdly, we analyze the effectiveness of three-way classification, and reveal the inner reason why the three-way decision can enhance the classification effect. Finally, we interpret the fusion mechanism between three-way decision and interpretive AI with a cognitive perspective, and give the research directions of interpretability three-way decision in future.关键词：three-way decisions;granular computing;roughset theory;decision-theoretic rough sets
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发布时间：2024-01-03 - 摘要：The study developed a walnut green husk immobilization bacterial agent using biochar and sulfate reducing bacteria, which was used to remediate heavy metal-contaminated soil.The fermentation effect of walnut green husk was evaluated based on pH, water content, total nutrients, organic matter, seed germination index and heavy metal content. An improved immobilized bacterial agent was obtained by dispensing biochar and inoculating with SRB15-3-2, and the effects of walnut green husk immobilized bacterial agent on the transformation of soil heavy metal fraction, plant growth and heavy metal enrichment capacity were investigated. The results showed that the immobilized bacterial agent of walnut green husk promoted the growth of green cabbage and increased the biomass.Compared with the control group (CK), the plant height of green cabbage in Cu and Cd contaminated soil with immobilized bacterial agent increased by 12.62% and 5.42%, respectively, and the dry weight of the aboveground part increased by 95.05% and 47.93%, respectively.In addition, the immobilized bacterial agent exhibited significant passivation of soil heavy metals and promoted the transformation of Cu and Cd from the exchangeable fraction to the residue fraction, thus reducing the mobility and biotoxicity of heavy metals.And the content of Cu and Cd in the underground part of the green cabbage was reduced by 92.92% and 72.82%, and the content of Cu and Cd in the aboveground part was reduced by 34.00% and 3.30% compared with that in the CK group.The results of this study provide scientific basis and theoretical support for the remediation of heavy metal contaminated soil and the resource utilization of walnut green husk.关键词：walnut green husk;immobilized bacterial agent;heavy metal;soil remediation
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发布时间：2024-01-03 - 摘要：The central problem of the BPHZ renormalization theory is to prove the absolute convergence of the integral of the renormalized Feynman wave function RΓ in Minkowski space. To prove this, one only has to prove the absolute convergence of the integral of the corresponding wave function in Euclidean space. Hahn and Zimmermann demonstrated this conclusion. This article also provides this result using Weinberg’s asymptotic theorem. Due to the different conditions required for proof, the field theories covered by the two methods are somewhat different. This paper can be divided into four parts: ① Introduction to Weinberg’s asymptotic theorem and An class function. ② Detailed derivation of the substantive part of the theorem. ③ Explain why An class functions in Rn must be absolutely integrable in the bounded region σ, prove the recursive relation of this condition from Rn to Rl(l<n). ④ Prove the
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发布时间：2024-01-03 - 摘要：The age of Sume, Durango, Otter Lake, AP1, MRC-1 standard apatites, and Ontario, T4, T3, Pakistan standard titanites were determined simultaneously by using Agilent 7900 inductively coupled plasma mass spectrometry and RESOLution S-155LR 193 nm ArF excimer laser ablation at the State Key Laboratory of Continental Dynamics, Northwest University, with laser frequency of 6 Hz and laser ablation spot size of 67 μm (apatite) and 43 μm(titanite). Using MAP-3 apatite as an external standard combined with 207Pb-correction method, the U-Pb weighted average ages of apatite samples, Sume(566.7±5.3)Ma, Durango(31.2±0.6)Ma, Otter Lake(901.3±9.6)Ma, AP1(472.0±3.9)Ma, MRC-1(155.4±1.8)Ma can be determined accurately.Using BLR-1titanite as an external standard combined with 207Pb-correction method, the U-Pb weighted average ages of titanite samples, Ontario(1 044.4±4.2)Ma, T4(1 096.2±5.6)Ma, Pakistan(20.74±0.61)Ma, T3(1 102.9±5.8)Ma can be determined accurately. These results are consistent with the recommended values within a reasonable range of error. The research results indicate that the established method can accurately determine the in-situ U-Pb dating of apatite and titanite, with high accuracy and reliability of the data results. The establishment of in situ apatite U-Pb provides important age information for medium temperature thermochronology studies. The establishment of in situ titanite U-Pb provides important evidences for exploring age information related to metamorphic and hydrothermal processes, and identifying P-T-t trajectories of geological bodies.关键词：LA-ICP-MS;apatite;titanite;U-Pb dating
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发布时间：2024-01-03
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