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The Global Stratotype Section and Point (GSSP) for the Permian-Triassic boundary was placed in Bed 27 of Meishan section D where the conodont species Hindeodus parvus first occurs. Bed 27 was usually considered comprising continuously-deposited, homogeneous silty limestone, with no depositional hiatus near the boundary. Detailed study on the boundary sequence revealed that a typical firmground characterized by Glossifungites ichnofacies developed about 2 cm below the Permian-Triassic boundary in Bed 27. Fossil content and lithology show apparent differences across the firmground crust. The abundance of the Permian bioclasts decreases significantly across the firmground, and is accompanied by a shift of dominating carbonate precipitation from calcite to dolomite. The firmground marked a rapid transgression at the very end of the Late Permian and significant shifts of sedimentary environment and paleoclimate. This transgressive submerging surface is also observed at the Huangzhishan section of the shallow-water carbonate platform facies in Zhejiang Province, the Jiangya section of the lower-slope to basinal-margin facies in Hunan Province, the Pingdingshan section of the basinal facies in Anhui Province of South China, as well as the Selong section in Tibet of the northern peri-Gondwana. The transgressive submerging surface marks the onset of a rapid global transgression at the latest Permian. [ABSTRACT FROM AUTHOR]

The Permian Period was a critical time interval during which various blocks of the Qinghai-Tibetan Plateau have experienced profound and complex paleogeographical changes. The supercontinent Pangea was formed to its maximum during this interval, hampering a global east-to-west trending equatorial warm ocean current. Meanwhile, a semi-closed Tethys Ocean warm pool formed an eastward-opening oceanic embayment of Pangea, and became an engine fostering the evolutions of organisms and environmental changes during the Paleozoic-Mesozoic transition. Stratigraphy and preserved fossil groups have proved extremely useful in understanding such changes and the evolutionary histories of the Qinghai-Tibetan Plateau. Widely distributed Permian deposits and fossils from various blocks of the Qinghai-Tibetan Plateau exhibited varied characteristics, reflecting these blocks' different paleolatitude settings and drifting histories. The Himalaya Tethys Zone south to the Yarlung Zangbo suture zone, located in the northern Gondwanan margin, yields fossil assemblages characterized by cold-water organisms throughout the Permian, and was affliated to those of the Gondwanaland. Most of the exotic limestone blocks within the Yarlung Zangbo suture zone are Guadalupian (Middle Permian) to Early Triassic in age. These exotic limestone blocks bear fossil assemblages that have transitional affinities between the warm Tethys and cold Gondwanan regions, suggesting that they most probably represent seamount deposits in the Neo-Tethys Ocean. During the Asselian to Sakmarian (Cisuralian, also Early Permian), the Cimmerian microcontinents in the northern part of Gondwana preserved glacio-marine deposits of Asselian to Sakmarian, and contained typical Gondwana-type cold-water faunas. By the middle Cisuralian (∼290–280 Ma), the Cimmerian microcontinents rifted off from the Gondwanaland, and drifted northward allometrically due to the active magmatism of the Panjal Traps in the northern margin of the Indian Plate. Two slices of microcontinents are discerned as a result of such allometic drifting. The northern Cimmerian microcontinent slice, consisting of South Qiangtang, Baoshan, and Sibuma blocks, drifted relatively quickly, and preserved widespread carbonate deposits and warm-water faunas since Artinskian. By contrast, the southern Cimmerian microcontinent slice, consisting of Lhasa, Tengchong, and Irrawaddy blocks, drifted relatively slowly, and were characterized by widespread carbonate deposits containing warm-water faunas of late Kungurian to Lopingian (Late Permian). As such, these blocks rifted off from the northern Gondwanan margin since at least the Kungurian. Thus, it can be inferred that these blocks were incorperated into the low latitude, warm-water regions later than the northern Cimmerian slice. Such discrepancies in depositional sequences and paleobiogeography imply that the rifting of Cimmerian microcontinents resulted in the formation of both Meso-Tethys and Neo-Tethys oceans during the Cisuralian. By contrast, the North Qiangtang block, because of its further northern paleogeographical position, contains warm-water faunas throughout the whole Permian Period that are affiliated well with the faunas from the South China, Simao, and Indochina blocks. Together, these blocks belonged to the members of the northern Paleo-Tethys Ocean. Thus, an archipelagic paleogeographical framework divided by Paleo-, Meso-, and Neo-Tethys oceans was formed, fostering a global biodiversity centre within the Tethys warm pool. Since most of the allochthonous blocks assembling the Qinghai-Tibetan Plateau were situated in the middle to high latitude regions during the Permian, they preserved most sensitive paleoclimate records of the Late Paleozoic Ice Age (LPIA), the Artinskian global warming event, and the rapid warming event at the end-Permian. Therefore, sedimentological and paleontological records of these blocks are the unique window through which we can understand global evolutions of tectonic movement and paleoclimate, and their impacts on spatiotemporal distributions of comtemporaneous biotas. [ABSTRACT FROM AUTHOR]

A vehicle detection algorithm is an indispensable component of intelligent traffic management and control systems, influencing the efficiency and functionality of the system. In this paper, we propose a lightweight improvement method for the YOLOv5 algorithm based on integrated perceptual attention, with few parameters and high detection accuracy. First, we propose a lightweight module IPA with a Transformer encoder based on integrated perceptual attention, which leads to a reduction in the number of parameters while capturing global dependencies for richer contextual information. Second, we propose a lightweight and efficient multiscale spatial channel reconstruction (MSCCR) module that does not increase parameter and computational complexity and facilitates representative feature learning. Finally, we incorporate the IPA module and the MSCCR module into the YOLOv5s backbone network to reduce model parameters and improve accuracy. The test results show that, compared with the original model, the model parameters decrease by about 9%, the average accuracy (mAP@50) increases by 3.1%, and the FLOPS does not increase. [ABSTRACT FROM AUTHOR]

The pursuit of higher recognition accuracy and speed with smaller model sizes has been a major research topic in the detection of surface defects in steel. In this paper, we propose an improved high-speed and high-precision Efficient Fusion Coordination network (EFC-YOLO) without increasing the model's size. Since modifications to enhance feature extraction in shallow networks tend to affect the speed of model inference, in order to simultaneously ensure the accuracy and speed of detection, we add the improved Fusion-Faster module to the backbone network of YOLOv7. Partial Convolution (PConv) serves as the basic operator of the module, which strengthens the feature-extraction ability of shallow networks while maintaining speed. Additionally, we incorporate the Shortcut Coordinate Attention (SCA) mechanism to better capture the location information dependency, considering both lightweight design and accuracy. The de-weighted Bi-directional Feature Pyramid Network (BiFPN) structure used in the neck part of the network improves the original Path Aggregation Network (PANet)-like structure by adding step branches and reducing computations, achieving better feature fusion. In the experiments conducted on the NEU-DET dataset, the final model achieved an 85.9% mAP and decreased the GFLOPs by 60%, effectively balancing the model's size with the accuracy and speed of detection. [ABSTRACT FROM AUTHOR]

With the popularity of ChatGPT, there has been increasing attention towards dialogue systems. Researchers are dedicated to designing a knowledgeable model that can engage in conversations like humans. Traditional seq2seq dialogue models often suffer from limited performance and the issue of generating safe responses. In recent years, large-scale pretrained language models have demonstrated their powerful capabilities across various domains. Many studies have leveraged these pretrained models for dialogue tasks to address concerns such as safe response generation. Pretrained models can enhance responses by carrying certain knowledge information after being pre-trained on large-scale data. However, when specific knowledge is required in a particular domain, the model may still generate bland or inappropriate responses, and the interpretability of such models is poor. Therefore, in this paper, we propose the KRP-DS model. We design a knowledge module that incorporates a knowledge graph as external knowledge in the dialogue system. The module utilizes contextual information for path reasoning and guides knowledge prediction. Finally, the predicted knowledge is used to enhance response generation. Experimental results show that our proposed model can effectively improve the quality and diversity of responses while having better interpretability, and outperforms baseline models in both automatic and human evaluations. [ABSTRACT FROM AUTHOR]

The tectonic setting of South China during the late Paleozoic is essential to understanding the geodynamics off the eastern margin of Pangea supercontinent due to its unique paleo‐position at the confluence of the Paleo‐Tethys and Panthalassic oceans. Limited late Paleozoic magmatic and matemorphic records in South China have hampered resolution of this tectonic setting. Here, we present integrated biostratigraphic, geochronological, and isotope geochemical data on the late Carboniferous siliciclastic rocks from southeast South China in order to decipher the tectonic evolution of the South China Block. The sandstones were predominantly sourced from the Wuyi Terrane via short‐distance transportation. Rapid exhumation of ca. 318 Ma plutonic rocks in the source region, evolution of source of magmatism, and continuous crustal thinning demonstrate that southeast South China underwent episodic lithospheric delamination triggered by thermal perturbation as a result of subduction of the paleo‐Pacific plate beneath the South China Block in the late Paleozoic. Plain Language Summary: The South China Block, composed of the Yangtze and Cathaysia blocks, lay off the eastern edge of Pangea supercontinent during the late Paleozoic, drifting in isolation near the paleoequator until eventually amalgamated with the North China Block in the Permian‐Triassic. Widespread carbonate platform sedimentation and the absence of significant contemporaneous magmatic, structural and metamorphic records are collectively interpreted to indicate a stable passive continent margin setting. Recently, abundant late Paleozoic detrital zircons have been reported from Permian‐Triassic siliciclastic rocks in southeast South China. Here we carried out an integrated biostratigraphic, detrital zircon geochronological and Hf isotope geochemical study on a late Carboniferous succession in South China. Our fusulinid biostratigraphy and ages of youngest detrital zircons suggest rapid exhumation of plutonic rocks of ca. 318.5 ± 6.8 Ma. Besides, the Cathaysia Block underwent a continuous thinning and two distinct tectono‐thermal events at 370 and 335 Ma. Hf isotopic data suggests a trend of lesser contribution of melts from younger crust for middle‐late Paleozoic magmatisms. We propose that the southeastern South China underwent episodic lithospheric delamination triggered by thermal perturbation as a result of subduction of the paleo‐Pacific plate beneath the South China Block in the late Paleozoic. Key Points: Granitoid rocks of ca. 318.5 Ma in source region were rapidly exposed in the late CarboniferousCathaysia Block underwent a continuous thinning with two distinct tectono‐thermal events at 370 and 335 Ma during the late PaleozoicThe southeastern South China underwent delamination triggered by subduction of the paleo‐Pacific plate during the late Paleozoic [ABSTRACT FROM AUTHOR]

The late Paleozoic ice age was the longest icehouse of the Phanerozoic with complex terrestrial ecosystems and metazoan life. Simulations of late Paleozoic climate have confirmed the coupled relationship between Gondwanan ice dynamics and paleotropical climate on a multitude of timescales. However, it is still unclear how precipitation in the tropical zone would respond to changes in paleoclimate during the late Paleozoic ice age. Here, we present detailed sedimentological and biostratigraphic works on a late Carboniferous mixed carbonate-siliciclastic succession from the southeastern South China Block to explore sedimentary responses to paleoclimate variations. Conodont and fusulinid biostratigraphy indicate that the Outangdi succession formed during the middle to late Moscovian. Detailed facies analysis suggests that the succession was deposited on a carbonate ramp, episodically punctuated by braid delta sedimentation. Given the relatively stable tectonic setting and well-correlated, coeval siliciclastic deposition in the paleotropical peri-Paleotethys regions, the abrupt increase in siliciclastic influx in the late Moscovian resulted from an enhanced precipitation event associated with the glacial-to-interglacial shift. • An abrupt siliciclastic influx were recorded in tropical peri-Paleotethys regions in the late Moscovian • Water cycle would be enhanced in the paleotropical zone responding to the demise of glacial interval • Anomalous siliciclastic deposits could have been driven by climate factors. [ABSTRACT FROM AUTHOR]

The Lopingian is one of the fastest rising periods of seawater strontium isotopic ratios (Sr/Sr) in earth history, and its mechanisms and increasing rates of the Sr/Sr evolution were still disputed widely. These disputations among researchers were caused mainly by timeframe selection (sections' thickness or data of radiometric ages), and different stratigraphic boundaries and un-upmost dated ages. This paper examined published Sr/Sr data of the Lopingian, and projected them on timescales based on evolutionary and age constrained conodonts fossils. Sr/Sr evolution vs fossil constraining timescales was re-established in this period. This research suggests: (1) Sr/Sr excursion projects on fossil zones can truly support Sr/Sr evolutionary pattern in the period; (2) Sr/Sr evolution provides a new approach for stratigraphic research of marine carbonate sections in lieu of biostratigraphic data; (3) Sr/Sr stratigraphy works on marine carbonate sections of different sedimentation rates even between different basins; (4) the Sr/Sr data and its shift was dependent on samples materials and chemical treatment methods; (5) the increasing rate of marine water Sr/Sr in the Late Permian is suggested as 5.4×10/Ma or slightly lower; (6) sedimentation age and its Sr/Sr of the Lopingian marine carbonate suggested as: D=259-( R−0.70695)/5.4×10±1 Ma. [ABSTRACT FROM AUTHOR]

Two negative carbon isotope excursions (3.5–6.5‰) across the Wuchiapingian-Changhsingian boundary (WCB) are observed globally (sections in China, Canada, and Iran); however, the causative mechanism of these excursions is debated. Here, high-resolution osmium isotope (187Os/188Os or Os i) chemostratigraphy of four globally correlated WCB sections (3 in China - Meishan, Shangsi and Lianyuan and 1 in Canada - Buchanan Lake) show two separate Os i excursions to less radiogenic compositions that are coincident with the carbon isotope shifts for two of the South China sections (Lianyuan, Meishan). In contrast, only a single Os i excursion to less radiogenic compositions, coinciding with the earliest Changhsingian carbon isotope shift, is observed for the Shangsi and Buchanan Lake sections. The Os i shift is interpreted to reflect increased unradiogenic Os input from basaltic magmatism in South China, possibly related to the Emeishan large igneous province (LIP). However, 187Os/188Os data suggest that only the earliest Changhsingian volcanism had global impact on both the ocean and atmosphere. The lack of any evidence for a biotic event associated with the WCB therefore may have been due to the more regional rather than global impact of volcanism during the latest Wuchiapingian. In contrast, during the earliest Changhsingian, volcanism was sufficient to cause a more global signal in the ocean osmium record, but was inadequate, or too prolonged, to drive any significant environmental change. Volcanism, however, may have provided the isotopically light carbon that drove the negative carbon isotope excursions across the WCB. [ABSTRACT FROM AUTHOR]