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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]

Subaqueous mass‐transport processes are one of the mechanisms for transport of sediment into the deep sea. Internal structures and depositional processes of carbonate mass‐transport deposits are relatively poorly understood relative to siliciclastic facies due to their comparative paucity in the rock record. A variety of carbonate mass‐transport deposits, including slumps, debrites and deep‐channel‐confined density flow deposits, occur in Middle–Upper Ordovician slope deposits in western Inner Mongolia (Wuhai), China. These provide a rare opportunity to illustrate the emplacement history of carbonate mass‐transport deposits at the outcrop scale. The slumps and debrites host remarkable folds, chaotic beds and imbricated beds that reflect differences in both rheology and position on the slope. Individual slump sheets show gradations between undulating laminae, inclined and recumbent folds, highly deformed folds, and chaotic textures upslope from the toe region. Debrites are commonly interbedded with slump deposits, whereas imbricated beds are present in the middle and lower parts of the toes of slump sheets near the terminal wall. In the study area, thin‐bedded limestone with slump deposits of the Kelimoli Formation are overlain by fine‐grained, siliciclastic‐dominated, slope deposits of the Wulalike Formation. A thick breccia of the Wulalike Formation was deposited in a main feeder channel in south‐east Wuhai, but to the west‐north‐west the breccia was deposited in distributary channels possibly represented as a unique lower‐slope pattern of gullies. At the latter locality, the breccia was deposited solely within the channels on a steep west‐north‐west dipping slope under density‐driven flows. The mass‐transport deposits documented herein records passive to foreland basin tectonic transitions, and associated platform foundering and steepening of the slope. A slope facies model was constructed to demonstrate the spatial and temporal variations of mass‐transport deposits during basin evolution, and as such it provides a template for the interpretation of the deposits of ancient slopes that underwent passive to active tectonic transitions. [ABSTRACT FROM AUTHOR]

Lime mud (i.e., micrite) is a major component of carbonate deposits. Various mechanisms (biotic versus abiotic) have been proposed for the formation of lime mud in Earth's history. However, the detailed role that microbes play in the nucleation and subsequent precipitation of micrites remains to be resolved. Herein we undertook a detailed geobiological characterization of laminated lime mudstone from the Middle Triassic Guanling Formation in Yunnan Province, southwestern China. Morphological features, together with previous geobiological investigations, suggest that the laminated lime mudstones represent the former presence of microbial mats. These lime mudstones consist mainly of calcite, dolomite and quartz, with clay minerals and pyrites as subordinate components. In particular, micro-analysis shows copious nano-globules (65–878 nm) and capsule-shaped nano-rods in laminations. These low-Mg calcite nano-globule aggregates are closely associated with mucilaginous biofilms resembling extracellular polymeric substances (EPS). Nano-sized globules coalesce to form semi-euhedral micrite crystals. We suggest that a decaying hydrolytic destruction of the EPS by microbial communities within microbial mat leads to the precipitation of the nano-globules by enhancing alkalinity in local micro-environment. As an intermediate, these nano-globules further aggregate to form micrite crystals possibly through a dissolution-reprecipitation process. [ABSTRACT FROM AUTHOR]

A positive carbonate δ13C excursion (by ~1.5–3.0‰) has been reported across the Mississippian–Pennsylvanian boundary (MPB) from Euramerican epicontinental seas, implying a coeval atmospheric pCO2 decrease and Gondwanan glaciation at that time. This excursion was mainly observed in carbonate platforms which experienced repeated subaerial exposure. The South China Block was located in the middle of the Paleo‐Tethys Ocean and the Panthalassic Ocean during the Carboniferous and contains well‐preserved carbonate slope strata across the MPB. Four lithofacies were defined in the studied Naqing, Narao, and Dianzishang sections, including thin‐bedded lime mudstones, laminated wackestones to packstones, normally‐graded packstones, and slumped limestones. Immediately above the MPB, a bed of normally‐graded packstones or slump masses occurs in the studied sections, which together with coeval subaerial‐exposure features in shallow‐water carbonate platform of South China, suggests a significant sea‐level fall across the MPB. Carbonate δ13C records show a consistent value of ~3.0‰ below the MPB in the Naqing and Narao sections, and both sections show an obvious rise in δ13C across the MPB (by ~0.5–1.0‰). The relatively small‐magnitude rise in δ13C would have resulted from well‐mixed seawater induced by intensified upwelling in the eastern Paleo‐Tethys Ocean during the glacial peak. Hence, the carbonate δ13C values recorded in the South China Block may represent a mean δ13C of the dissolved inorganic carbon in global ocean water at that time. Correlation between carbonate δ13C and previously published conodont δ18O and 87Sr/86Sr records suggests that the MPB glaciation was mainly driven by enhanced continental weathering, rather than increased organic carbon burial, although further quantitative simulation is required to better understand the interlinked processes during the Earth's penultimate icehouse. [ABSTRACT FROM AUTHOR]

[Display omitted] In the past, neuropeptide substance P (SP) was predominantly recognized as a neuroinflammatory factor, while its potent healing activity was overlooked. This paper aims to review the regulatory characteristics of neuropeptide SP in both normal and diabetic wound healing. SP actively in the regulation of wound healing-related cells directly and indirectly, exhibiting robust inflammatory properties, promoting cell proliferation and migration and restoring the activity and paracrine ability of skin cells under diabetic conditions. Furthermore, SP not only regulates healing-related cells but also orchestrates the immune environment, thereby presenting unique and promising application prospects in wound intervention. As new SP-based preparations are being explored, SP-related drugs are poised to become an effective therapeutic intervention for diabetic foot ulcers (DFU). [ABSTRACT FROM AUTHOR]

Graphical abstract The carboxyl tagged on anatase provides the binding sites of As(III) and Cr(VI) ions that enables the electron transfer from As(III) to Cr(VI) on the TiO 2 surface. Highlights • COOH functionalized anatase (TiO 2 @C) was first obtained from MIL-125(Ti). • The TiO 2 @C shows great catalytic activity of redox between As(III) and Cr(VI). • The coupled redox on the surface of TiO 2 @C was achieved without any energy input. • The concomitant adsorption of As(V) leads to the elimination of total arsenic. • A microscopic mechanism of the mutual conversion via TiO 2 @C was revealed. Abstract MIL-125(Ti)-derived titanium oxides, a functionalized cake-like 3D material, is becoming increasingly attractive to researchers. In this work, COOH functionalized anatase TiO 2 (TiO 2 @C) was prepared by one-step calcination method. And the TiO 2 @C, as a novel catalyst, was used to accelerate electron transfer from As(III) to Cr(VI) for simultaneous Cr(VI) reduction and As(III) oxidization in aqueous solution. The results showed that the addition of TiO 2 @C greatly accelerates the coupled As(III)/Cr(VI) reaction. This reaction is further enhanced at acidic pH and higher concentrations of material. Furthermore, the mutual conversion is equally sensitive to ion initial concentration. Accordingly, a new microscopic redox reaction process of As(III) and Cr(VI) was proposed, which was first made clear of the mutual redox via XPS and FTIR analysis. To be specific, the carboxyl on anatase not only offers As(III) and Cr(VI) ions binding sites, but also initiates the electron transfer from As(III) to Cr(VI) on the solid surface. While the cake-like geometry with high surface area serves for the electron transfer pathways. This unparalleled reaction mechanism enlighten us on a new field of COOH functionalized catalyst used for the coupled removal of As(III)/Cr(VI). [ABSTRACT FROM AUTHOR]

This paper focuses on the depositional processes and environmental changes during initial marine flooding recorded in the lower Cambrian succession of the North China Platform in Shandong Province, China. In order to understand imbalance of accommodation and sediment supply in the initial stage of basin-fill, a detailed analysis of sedimentary facies was made for the lowermost siliciclastic deposits of the Liguan Formation. It reveals ten siliciclastic lithofacies in three large-scale outcrops (Jinhe, Anqianzhuang, and Zhangjiapo sections). These facies are grouped into four facies associations, representing siliciclastic foreshore-shoreface (S1), siliciclastic offshore (S2), distributary mouth bars (S3), and coastal plain (S4). The siliciclastic components occur in a linear belt, emanating from a major drainage system in the northeastern part of the platform. Deposition of siliciclastic sediments was largely controlled by regional topography of the unconformable surface and shoreline configuration as well as strong effect of waves and currents. With ensued rise in sea level and decrease in siliciclastic sediment supply, carbonate sediments prevailed, filling the accommodation created by epeirogenic subsidence and sediment loading. [ABSTRACT FROM AUTHOR]

Geological and paleomagnetic data indicate that the ice sheets might have extended to low-latitude regions in the Cryogenian (720–635 Ma). The ‘snowball Earth’ hypothesis proposed that the Earth was completely ice-covered during global glaciation. However, the glacial sedimentary record seems to contradict with the snowball Earth hypothesis. Detailed sedimentological investigations of the glacial deposits would provide the first-order constraint on the nature of global glaciation. The Nantuo Formation (∼654–635 Ma) in the Yangtze Block of South China has been correlated with the Marinoan snowball Earth. In this study, we conducted systematic sedimentological analyses of six sections/cores of the Nantuo Formation. Three facies associations were recognized: the proximal glaciomarine, distal glaciomarine, and non-glacial marine facies associations. The vertical stacking pattern of facies associations can be correlated among the five slope and basin sections, while their correlation with the shelf section remains obscure. Our data indicate two episodes of glaciation that are separated by an interglacial interval during the Nantuo Glaciation. The first glacial episode is recorded by successions of coarse-grained facies (e.g., massive diamictite) in the lower part of the Nantuo Formation. The re-appearance of massive diamictite in the middle to upper part of the Nantuo Formation indicates onset of the second glacial episode. These two glacial episodes were separated by a siltstone/shale sequence of several 10 s m thick, suggesting an interglacial period with limited influence from glaciation. The top of Nantuo Formation consists of alternative distal-glaciomarine and non-glacial marine facies associations, representing the deglacial sequence of the Nantuo Glaciation. The sedimentary facies analysis indicates that the cold climate during the Nantuo Glaciation may be cyclic. Finally, our sedimentary analysis confirms a lag between the deglaciation and precipitation of cap carbonate. [ABSTRACT FROM AUTHOR]

Sodium hypophosphite induced a simultaneous P doping and hollowing process of TiO2 spherical nanostructures and produced P-doped hollow spherical nanostructures via a simple one-step hydrothermal method. The as-synthesized P-doped hollow spherical nanostructures demonstrated significantly enhanced photocatalytic activity for MB degradation compared to the undoped TiO2 and P25 under sunlight irradiation. [ABSTRACT FROM AUTHOR]

A calcination time regulation method has been unprecedentedly used to adjust the orderly meso-structure of novel α-Fe 2 O 3 nanoclusters derived from MIL-100(Fe) (MIL: Materials of Institute Lavoisier). The as-synthesized magnetic orderly mesoporous α-Fe 2 O 3 nanoclusters were characterized by XRD, SEM, TEM, TGA, N 2 adsorption-desorption isotherms, VSM, Zeta potential, FTIR and XPS. The 6 h calcinated α-Fe 2 O 3 nanocluster exhibited the optimal properties, including the high specific surface area and the orderly mesoporous properties, which facilitate the arsenic(III,V) adsorption capacity. The maximum adsorption capacities of As(III) and As(V) were 109.89 and 181.82 mg g −1 , respectively, and adsorption equilibrium can be reached just within 30 min. The kinetics intra-particle diffusion model and adsorption isotherms reveal that the adsorption rate is controlled by pore diffusion and the adsorption process belongs to Langmuir monolayer adsorption. These results indicate that the orderly mesoporous structure of α-Fe 2 O 3 nanoclusters plays a key role in rapid and efficient adsorption for arsenic(III,V). Meanwhile, adsorption mechanism verifies that arsenic can react with active sites (Fe-OH) to form complexes by Fe-O-As bond. Moreover, α-Fe 2 O 3 nanocluster can be separated easily due to its excellent magnetism. Above all, the magnetism orderly mesoporous α-Fe 2 O 3 nanocluster is a promising adsorbent for emergent treatment of arsenic in practice. [ABSTRACT FROM AUTHOR]

Increasing evidence suggests that therapy-induced senescence (TIS), a novel therapeutic approach in which low doses of therapeutic drugs or radiation are used to induce senescence, suppresses tumor development. Our previous in vitro studies have demonstrated that a low dose of metformin promoted hepatoma cell senescence instead of apoptosis via activation of AMP-activated protein kinase (AMPK) and inactivation of Sirtuin 1 (SIRT1) deacetylase activity. However, the intricate relationship between AMPK and SIRT1, and how they cooperate to induce senescence remains elusive. We showed here that persistent exposure to a low concentration of metformin led to AMPK activation in a mouse xenograft model of human hepatocellular carcinoma (HCC), resulting in senescence. Intriguingly, AMPK counter-regulated SIRT1 via direct phosphorylation in metformin-mediated senescence in hepatoma cells. Taken together, these findings suggest that a low dose of metformin could potentially be used as a TIS-inducing therapeutic drug for HCC, and that this occurs by inducing senescence of HCC cells via the AMPK-SIRT1 pathway. [ABSTRACT FROM AUTHOR]

Maceriate reefs, characterized by centimeter- to decimeter-scale branching structures, flourished during the Cambrian to Early Ordovician on Laurentia, and Gondwana (the North China Platform). Dendritic and columnar maceriate reefs were newly discovered from the northwestern and central parts of the North China Platform. The maceria structures are composed of sponges (e.g., keratosans and lithistids) and microbial components, including Girvanella , Renalcis , and Tarthinia , whereas the interstitial material consists of lime mud with bioclasts and intraclasts. The first appearance of maceriate reefs was diachronous across the North China Platform, younging from the northwest (Drumian Age, Miaolingian) to the southeast (Jiangshanian Age, Furongian). In general, thrombolites and dendrolites were dominant in the microbialite-dominated reefs of the Miaolingian and microbe–sponge maceriate reefs were dominant in the Furongian. This dramatic shift to microbe–metazoan reef assemblages resulted from a combination of factors associated with the Miaolingian–Furongian boundary interval, including global transgression and a shift from widespread anoxia of the SPICE event to more oxygenated post-SPICE conditions. The North China examples suggest that sea level and paleoenvironmental conditions may have played a major role in this transition and its timing. • Newly discovered dendritic and columnar maceriate reefs from the North China Platform. • Diachronous occurrence of maceriate reefs across the NCP, younging from the northwest to the southeast. • Paleoenvironmental conditions as a major controlling factor for the spatio-temporal distribution and reef transition. [ABSTRACT FROM AUTHOR]

The Late Paleozoic Ice Age (LPIA) is the so far longest-last icehouse climate state during the Phanerozoic, and recorded a complete transition from icehouse to greenhouse climate state since the occurrence of vascular plants and complex terrestrial ecosystem. Therefore, integrated studies on the icehouse-greenhouse transition of the LPIA are critical to understanding the driver and mechanism of the deep-time paleoclimate system, particularly in an icehouse climate state. However, frequent subaerial exposures and stratigraphic discontinuities in low-latitude areas due to glacio-eustatic changes from the Pennsylvanian (Late Carboniferous) to Cisuralian (Early Permian) potentially altered the primary δ13C signals, which hampered a valid global correlation. Here, three carbonate slope successions (Naqing, Shanglong, and Narao) in the Luodian Basin, South China Block, were selected for detailed sedimentology and high-resolution carbonate δ13C study. The variation of δ13C is compared with the sedimentary characteristics and can be correlated with global glacial events and atmospheric p CO 2 during the apex and deglaciation period of the LPIA. It suggests that δ13C of the Luodian Basin can potentially represent the global mean δ13C of the seawater dissolved inorganic carbon and provide a reference for the future study on global carbon cycling. • Detailed sedimentary facies and high-resolution δ13C carb time series in the Luodian Basin • δ13C carb of the Luodian Basin as a reliable proxy for global carbon cycling • A potential linkage between global carbon cycling and evolution of the LPIA [ABSTRACT FROM AUTHOR]

Variability in stratigraphic accumulation rates and distribution of stratal hiatuses along with strong endemism of index fossils hinder regional to global stratigraphic correlation of the Visean–Serpukhovian (V–S) boundary interval (late Mississippian) and thus geological inferences regarding the onset of the late Paleozoic ice age. Here we integrate high-resolution δ 13 C time series with detailed sedimentary facies analysis of late Visean–early Serpukhovian (V–S) carbonate platform-to-slope successions from South China to evaluate the influences of local depositional and diagenetic processes on δ 13 C carb and to address the correlation issue. Analysis of 11 sedimentary facies from 5 outcrop sections indicates a restricted platform setting (Yashui section) dominated by bioclastic wacke-packstone to lime mudstone in which paleokarst developed, and contemporaneous carbonate slope settings dominated by thin-bedded lime mudstones intercalated with slumps and calciturbidites. Based on vertical facies assemblages, three depositional units are recognized, recording a significant sea-level drawdown across the V–S boundary. Multiple negative δ 13 C excursions (> 1‰) can be correlated across the V–S boundary interval in several slope sections (Naqing, Luokun, and Narao sections). Variability in the V–S boundary δ 13 C record in some sections is interpreted to record truncation physically by submarine erosion by slumps or chemically during karstification. A long-term decrease in δ 13 C values through the Serpukhovian of the Yashui section likely records local influences on carbon cycling in the restricted platform setting. This negative δ 13 C trend and associated depositional facies at the Yashui section can be correlated to the Arrow Canyon section, USA, which, together with other coeval global sedimentary and geochemical records, indicate a widespread eustatic drawdown in the late Visean with initial buildup of Gondwanan ice sheets. We conclude that integrated sedimentary facies analysis and δ 13 C chemostratigraphy can be used for stratigraphic correlation when interpreted within a well-constrained sedimentary and carbon-isotope regional framework. [ABSTRACT FROM AUTHOR]

Carbonate hardgrounds are lithified seafloors formed by synsedimentary cementation of carbonate sediments, which dominantly occur during the period of calcite seas. The earliest typical Phanerozoic hardground known until now was reported from the Furongian of USA, which was suggested to indicate onset of the early Paleozoic calcite sea period. In this study, we report hardgrounds from the early and middle parts of the Cambrian Series 3 (Stage 5 and Drumian) of the North China Platform, which predate previously reported hardgrounds. The hardground surfaces developed on oolitic grainstone, oncolitic wackestone, and microbialite (thrombolite and dendrolite), which sharply truncate the underlying deposits. The radial fibrous calcite cements between the carbonate grains below the hardground surfaces indicate that the cements formed by early marine cementation. EPMA analysis reveals that the fibrous cements typically consist of low-Mg calcite. The hardgrounds are sometimes encrusted by microbialites and coated by hematite, suggesting long exposure to the open seawater after formation of the surface. In addition, detailed review on the sedimentological studies of Cambrian Series 3 to Furongian deposits throughout the world reveals that there may be several other hardgrounds during these times, which could have been overlooked. The abundant occurrence of hardgrounds in Cambrian Series 3 deposits suggests that the general paleoseawater chemistry was suitable to induce synsedimentary cementation of low-Mg calcite, implying that seawater chemistry would have changed from the aragonite to calcite seas during the Cambrian Series 3 or even earlier period. Metazoan encrustors and macroborers possibly could not have adapted to the newly appeared substrate condition yet, until the latest Cambrian Series 3. [ABSTRACT FROM AUTHOR]

Reduced graphene oxide (rGO)-based materials have shown good performance as electrodes in flexible energy storage devices owing to their physical properties, high specific surface area, and excellent electrical conductivity. Here, a novel road is reported for fabricating high-performance supercapacitors based on 3D rGO electrodes and solid electrolyte multilayers via pressure spray printing and machine coating. These supercapacitors demonstrate high and adjustable volumetric capacitance, excellent flexibility, and stretchability. The results show that this commercial strategy has its essential merits such as low-cost, inexpensive, and simple fabrication for large area production. These properties are in the favor of fabricating high-performance supercapacitor to meet the practical energy demands in devices, especially flexible electronic devices. Furthermore, this novel 3D interdigital electrode concept can be widely applied to other energy devices for enhancing performances and to other micro devices for reducing cost. [ABSTRACT FROM AUTHOR]

The Baoshan, Tengchong, Lhasa, South Qiangtang, and Sibumasu terranes were part of Gondwana prior to rifting and drifting from the northern margin since the Early Permian. However, paleopositions of these terranes during the late Paleozoic remain controversial, which hinders better understanding the tectonic evolution of the Paleo-Tethys and glacier distribution patterns on eastern Gondwana during the late Paleozoic ice age. As robust provenance indicators, detrital zircon U–Pb dating and Hf isotope signatures have been widely utilized in paleogeographic reconstruction. Here, we collected a total of 8209 detrital zircon U–Pb ages and 1606 zircon Hf isotopic values from Paleozoic strata of northeastern Gondwana. These data are utilized to evaluate their paleopositions relative to Australian and Indian Gondwana through semi-quantitative data analysis. Our new paleogeographic model indicates that the South Qiangtang, Baoshan, and part of Sibumasu were outboard of the northern margin of Indian Gondwana during the Paleozoic, whereas the Lhasa and Sumatra terranes were located along the northern margin of Australia. Based on provenance shifts of late Paleozoic glaciogenic sedimentary rocks in northeastern Gondwana, two main ice sheets are hypothesized to have developed during the late Paleozoic. This study further confirms the model of a multicenter glacier distribution pattern on Gondwana during the late Paleozoic ice age from a perspective of provenance. [ABSTRACT FROM AUTHOR]

The reefs of the middle–late Cambrian (Cambrian Epoch 3–Furongian) have long been simply considered as microbialites that flourished in the aftermath of the archaeocyath extinction. Thorough review of the reefs in these periods shows, however, that the Cambrian Epoch 3 and the Furongian actually yield different types of reefs. The Cambrian Epoch 3 reefs are dominated by thrombolites and dendrolites, largely constructed by the calcified microbes Epiphyton and Renalcis . On the other hand, the Furongian reefs consist mainly of maze-like maceriate reefs and columnar stromatolites. The maceriate reefs most likely formed by siliceous sponges and calcified microbes including Girvanella and Tarthinia , whereas the columnar stromatolites were mainly constructed by Girvanella , Tarthinia , and minor siliceous sponges. Other microbial reefs (e.g., non-columnar stromatolites) persisted during the Cambrian Epoch 3 and the Furongian, mainly as small patch reefs or reefal crusts. Lithistid sponge-microbial reefs initially formed in the Cambrian Epoch 3 and occurred throughout the Furongian, but occupied only a minor portion during these periods. Several geological events occurred across the boundary between the Cambrian Epoch 3 and the Furongian, including positive carbon and sulfur isotope excursions, a eustatic sea-level drop, major faunal turnover of trilobites, and diversification of new organisms. The coincidence of these events and the transition in reefal fabrics suggest that reef ecosystems were significantly influenced by at least some of these events. Among the events, it is likely that sea-level change would have affected reefs, although further studies are required in order to test whether and how the other events influenced the reef transition. Epiphyton and Renalcis (and thrombolites and dendrolites formed by them) declined greatly most likely due to sea-level fall and thus decreased in shallow marine habitat at the end of Cambrian Epoch 3. The Cambrian Epoch 3 thrombolites and dendrolites were gradually replaced by a sponge-microbial association of the maze-like, maceriate reefs and the columnar stromatolites in the Furongian, coincident with a sea-level rise. [ABSTRACT FROM AUTHOR]

Limestone breccias are a common phenomenon in the Cambrian successions worldwide. They bear important geological implications that have attracted geologists for several decades. There are, however, still controversies on their origins, especially those of the breccias with abundant vertically orientated clasts. The Furongian (upper Cambrian) Chaomidian Formation of the North China Platform contains numerous levels of limestone breccias and conglomerates that provide an excellent example to look into their formative processes. These breccias and conglomerates have been the focus of study and discussion since the 1980s, but yet there is still no consensus with respect to their geneses. Recently, Van Loon and others argued that the vertically orientated clasts of the breccias developed by a number of simultaneous 'fountains' on the paleo-seafloor; the 'fountains' formed by upward-directed fluidized flows originated from the sediment underlying the brecciated limestones. While the novel 'fountain' hypothesis is not impossible, based on field evidences and theoretical considerations, however, it is most likely that the vertically orientated clasts resulted from their re-orientation by upward flow of thixotropically liquidized, uncemented argillaceous sediment that was interbedded with brecciated limestone fragments. Besides, the deformation processes most likely took place under shallow burial. [ABSTRACT FROM AUTHOR]

A variety of unusual early post-depositional deformation structures exist in grainstone and flat-pebble conglomerate beds of Upper Cambrian strata, western Colorado, including slide scarps, thrusted beds, irregular blocks and internally deformed beds. Thrusted beds up to tens of centimetres thick record thrust movement of a part of a bed onto itself along a moderate to steeply inclined (15° to 40°) ramp, locally producing hanging wall lenses with fault-bend geometries. Thrust plane orientations are widely distributed, and in some cases nearly oppositely oriented in close proximity, indicating that they did not form as failures acted upon by gravity forces. Irregular bedded to internally deformed blocks are isolated on generally flat upper bedding surfaces. These features represent parts of beds that detached, moved up onto and some distances across, the laterally adjacent undisturbed bed surfaces. Deformation of thin intervals of mud on the ocean floor by moving blocks rules out the possibility of storm-induced deformation, because the mud was not eroded by high shear stresses that would accompany the extremely large forces required to produce and move the blocks. Finally, internally deformed beds are characterized by large blocks, fitted fabrics of highly irregular fragments and contorted lamination, which represent heterogeneous deformation, such as brecciation and liquefaction. The deformation structures were produced by earthquakes linked to the reactivation of Mesoproterozoic, crustal-scale shear zones in the central Rockies during the Late Cambrian. Analysis of the deformation structures indicates very large body forces and calculated earthquake-generated ground motion velocities of ca 1·6 m sec−1. These correspond to moment magnitudes of ca 7·0 or more and a Mercalli Intensity of X+. These are the only known magnitude estimates of Phanerozoic (other than Quaternary) large-intensity earthquakes for the Rocky Mountain region, and they are as large as, or larger than, previous estimates of Proterozoic earthquakes along these major shear zones of the central Rockies. [ABSTRACT FROM AUTHOR]

The Cambrian Series 3–Furongian successions of the North China Platform contain various microbial–metazoan and microbial reefs. This study focuses on Furongian reefs of the platform in order to understand formative processes and the evolution of the reefs during Cambrian Epoch 3 and the Furongian. Three types of Furongian reefs were differentiated in the Shandong region, China: maceriate reefs, columnar stromatolitic reefs, and small-scale microbial reefs. Maceriate reefs show dm- to m-scale domal or flat-bedded geometry, and consist of cm-scale maze-like maceria structures made of siliceous sponges and microbial components (microstromatolites, Girvanella , and Tarthinia ). Columnar stromatolitic reefs are characterized by stromatolite columns of 10–100 cm in height and 5–50 cm in diameter. They consist dominantly of Girvanella , with less conspicuous, poorly preserved sponge spicule networks. Small-scale microbial reefs commonly show cm- to dm-scale, domal macrostructures, and were constructed mainly by calcimicrobes, Girvanella and Renalcis . These three types of Furongian reefs were deposited in various shallow-marine settings in response to relative sea-level changes. The Furongian reefs are markedly different, in terms of macro- and micro-fabrics, from the Cambrian Series 3 reefs that are dominated by thrombolites and dendrolites and were constructed mainly by Epiphyton in the Shandong region. This difference is also recognized in the Beijing region, ca. 500 km away. The abrupt transition from the Cambrian Series 3-type to Furongian-type reefs, coincidently with a decrease in calcified microbe diversity, was most likely due to global euxinic oceanic conditions and a possible eustatic sea-level drop, rather than the highly diachronous, platform-wide drowning event (i.e., drowning of the Cambrian Series 3 carbonate platform). The abundant occurrence of sponge spicule networks in the Furongian reefs suggests that metazoan reef builders (i.e., sponges) resurged and became actively involved in the reefal systems prior to the Great Ordovician Biodiversification Event. This study may provide an important basis for further investigation into the evolution of reefal systems during the middle to late Cambrian when metazoan reef-builders were known to be scarce. [ABSTRACT FROM AUTHOR]

The Huanghebei Coalfield, one of the coal production bases in North China, was considered as a coalfield without coal-bed methane ( CBM) during past decades. In recent years, however, CBM has been discovered in coal-bearing successions. In order to understand the CBM geological characteristics and accumulation process in this area, fifteen coal samples were collected and analyzed with respect to coal maceral and reflectance. The result shows that the gas distribution is uneven and the content varies in different areas even for the same coal bed. The storage of CBM is affected by geological factors such as burial depth, geological structures, and magmatic intrusion, among which the former two are more important in the formation of CBM. Deep burial of coal beds with the presence of cap-rock mudstone can seal CBM. The CBM is also accumulated and preserved at the place where normal faults are distributed. Magmatic intrusion causes contact metamorphism and controls the CBM formation by heating the coal-bearing successions. The obtained data indicate the geological conditions in northeastern Zhaoguan Mine are preferable for CBM formation and conservation; recent exploration estimates the CBM geological reserves up to 282.16 Mm3 and average of reserve abundance at 0.1662 × 108 m3 km−2. The Changqing Mine is a potential prospect in terms of CBM exploration since its geological conditions (structures and burial depth) are similar to the Zhaoguan Mine and its cap rock is even better. [ABSTRACT FROM AUTHOR]

Some limestone breccias and conglomerates from the Furongian (Late Cambrian) Chaomidian Formation (Shandong Province, China) were investigated in order to understand the depositional and deformational processes induced by storms. The sediments under study occur in a hummocky cross-stratified peloidal grainstone layer. The limestone conglomerates consist of well-rounded clasts that are mostly flat-lying or imbricated, and have erosional bases. They formed by surface reworking (erosion and rip-up) of thin-bedded grainstones by storm waves and currents. The limestone breccias consist of subangular to subrounded clasts of grainstone, which are often associated with small-scale grainstone clastic dykes. The breccias and dykes resulted from subsurface soft-sediment deformation (i.e., differential liquefaction and fluidization of heterogeneously cemented carbonate grains), most likely triggered by storm-wave loading. The limestone breccias and conglomerates bear important implications for understanding the reworking mechanisms of storms on ancient carbonate platforms [ABSTRACT FROM AUTHOR]

This paper reviews the current progress and problems in the study of microbialites and microbial carbonates. Microbialites and microbial carbonates, formed during growth of microbes by their calcification and binding of detrital sediment, have recently become one of the most popular geological topics. They occur throughout the entire geological history, and bear important theoretical and economic significances due to their complex structures and formative processes. Microbialites are in place benthic microbial buildups, whereas microbial carbonates can be classified into two categories: stabilized microbial carbonates (i.e., carbonate microbialites, such as stromatolites and thrombolites) and mobilized microbial carbonates (i.e., microbial carbonate grains, such as oncoids and microbial lumps). Various texture, structures, and morphologies of microbialites and microbial carbonates hamper the systematic description and classification. Moreover, complex calcification pathways and diagenetic modifications further obscure the origin of some microbialites and microbial carbonates. Recent findings of abundant sponge spicules in previously identified 'microbialites' challenge the traditional views about the origins of these 'microbialites' and their implications to reef evolution. Microbialites and microbial carbonates did not always flourish in the aftermath of extinction events, which, together with other evidences, suggests that they are affected not only by metazoans but also by other geological factors. Their growth, development, and demise are also closely related to sea-level changes, due to their dependence on water depth, clarity, nutrient, and sunlight. Detailed studies on microbialites and microbial carbonates throughout geological history would certainly help understand causes and effects of major geological events as well as the coevolution of life and environment. [ABSTRACT FROM AUTHOR]

Abstract: This paper focuses on soft-sediment deformation structures (SSDS) in both siliciclastic and carbonate storm deposits of the Cambrian Mantou and Chaomidian formations (Shandong Province, China) in order to understand their deformation mechanisms and possible triggers. Siliciclastic SSDS (e.g., sand volcanoes and pillows) and carbonate SSDS (e.g., sedimentary dykes, grainstone-matrix breccias, deformed cross-beddings, and marlstone-matrix breccias) occur exclusively in hummocky cross-stratified fine sandstone and peloidal grainstone, respectively. The siliciclastic SSDS formed in porous and permeable surface sediment, whereas the carbonate SSDS formed under shallow burial conditions when early marine cementation prevailed. The various deformation structures resulted mainly from differences between siliciclastic and carbonate sediment conditions and resulting deformation mechanisms. Sand volcanoes formed by upward extrusion of over-pressured fluidized sandy sediment, whereas sand pillows resulted from upward injection of lower density muddy sediment into overlying liquefied sandy sediment. Sedimentary dykes and grainstone-matrix limestone breccias formed as a result of differential liquefaction and fluidization of heterogeneously cemented carbonate sediment, whereas deformed cross-beddings and marlstone-matrix limestone breccias developed by the thixotropic liquidization and injection of clayey sediment, and further disruption of thin peloidal layers. Sedimentary facies analysis and analysis of the physical processes indicate that the SSDS were most likely caused by cyclic loading of storm waves. [Copyright &y& Elsevier]

In order to diagnose emplacement of discordant breccia body in carbonate platform, we here describe sedimentary structures and texture as well as bed geometry of two beds of the Chaomidian Formation (Frongian) in Shandong Province, China. Each breccia body consists of granule- to cobble-size clasts of peloidal grainstone and matrices of dolomitic marlstone and/or micritic limestone, showing a tunnel geometry. Marlstone in the matrix is homogeneous, whereas micritic limestone shows irregular and disoriented laminations. It is hypothesized that the breccia body formed by subsurface in situ fluidization and fragmentation and further injection into the ambient deposits. Subsurface sediment remobilization occurred most likely under cyclic loading of large storm waves. The laminated matrix is strongly suggestive of hydroplastic deformation (flowage) of fluidized material during injection. This study suggests that there exists a full spectrum of subsurface deformation from liquefaction/fluidization to injection flow. [ABSTRACT FROM AUTHOR]

Highlights: [•] Detailed facies analysis for the Late Carboniferous−Early Permian successions. [•] Establish a sequence-stratigraphic framework in an epicontinental basin. [•] Comparison of the relative sea-level curves in North China and South Korea. [ABSTRACT FROM AUTHOR]

This study focuses on the stratigraphic sequences and the bounding surfaces in the upper Cambrian Series 3 to Furongian Gushan and Chaomidian formations in the Shandong region, China. The bounding surfaces are compared with those of the coeval succession in the Taebaek area, Korea. According to the vertical arrangement of the facies associations and the identification of the bounding surfaces, three stratigraphic sequences are recognized, representing dynamic changes in accommodation versus sedimentation. The bounding surfaces can be traced in the Shandong region for about 6,000 km in area, but cannot be correlated with those of the Taebaek area (eastern margin of the platform, about 1,000 km apart). Surface 1 is characterized by an abrupt facies change from carbonate to shale, representing a distinct drowning surface. The drowning surface is also diagnosed in the Taebaek area but highly diachronous. Surface 2 is a cryptic subaerial unconformity, reflected by an erosion surface, missing of a trilobite biozone ( Prochuangia Zone), and an abrupt increase in carbon isotope value. It is not identified in the Taebaek area where the Prochuangia Zone is present. Surface 3 is a marine flooding surface, indicated by a subtle transition from flat-bedded microbialite to domal microbialite (or grainstone). It may be correlated with that in the Taebaek area, which is, however, represented by an abrupt facies change from sandstone to limestone-shale alternation. The high variability of the sequence-bounding surfaces is indicative of variable regional factors such as topographic relief, carbonate production, siliciclastic input, and hydrodynamic conditions. It suggests that the sequence-bounding surfaces are invalid for a basin-scale correlation, especially in an epeiric carbonate platform. [ABSTRACT FROM AUTHOR]

This study focuses on an extensive biostromal microbialite (10-20 m in thickness and over 6,000 km in area) and the overlying grainstones in the Furongian Chaomidian Formation, Shandong Province, China in order to understand the demise of the microbialite. The microbialites are characterized by centimeter-to decimeter-scale maze-like maceria structures and/or chaotic mesostructures. According to the megastructures of microbialites and the proportion of non-microbial carbonate sediment, the biostromal microbialite is generally divided into the lower and the upper parts, separated by a distinct surface. The lower part is laterally continuous and generally flat-bedded, whereas the upper part shows variable domal megastructures and locally co-occurs with abundant non-microbial carbonate sediment. The entire microbialite bed is sharply overlain by grainstone-dominated deposits via an erosion surface which is either irregular with significant relief or flat with hematitic coating. The lower part of the biostromal microbialites with flat-bedded megastructures most likely deposited contemporaneously during sea-level highstand in the early middle Furongian, as evinced by well-correlated flat-bedded units separated by distinct bounding surfaces. The microbialites formed regional topographic variation, generally deepening toward southeast. The flat-bedded microbialites were drowned by subsequent rapid rise in sea level. In the topographic highs, the microbialites caught up with sea-level rise, forming large-scale domal megastructures. In the topographic lows, however, domal microbialites formed together with abundant non-microbial sediment, which were frequently reworked by storm-induced waves and currents. Subsequent deposition and migration of coarse-grained non-microbial sediment during sea-level rise terminated the entire microbialites. [ABSTRACT FROM AUTHOR]

Abstract: In order to understand sequence development and sea-level fluctuations during the late Middle Cambrian to early Furongian on the North China epeiric platform, the present study focuses on a unique, subtle erosion surface of an extensive (approx. 100km), strongly deformed limestone bed in the uppermost part of the Gushan Formation, Shandong Province, China. The Gushan Formation and the overlying Chaomidian Formation consist mainly of shales and a variety of carbonates that were deposited in subtidal environments (e.g., deep subtidal, shallow subtidal, shoreface/shoal, subtidal microbial flat, and restricted platform interior). Three third-order depositional sequences (S1–3) are identified, each of which comprises a thin transgressive systems tract (TST) and a relatively thick highstand systems tract (HST). Each sequence is bounded by a drowning unconformity (SB1), a subaerial unconformity (SB2), or a surface of submarine erosion (SB3). The upper sequence boundary (SB2) of sequence 1 (S1) is represented by a subtle erosion surface of an extensive, deformed limestone bed with a wide variety of soft-sediment deformation structures (e.g., lime mudstone breccias, chaotic wacke-packstone laminae and fragments, homogenized oolites, and clastic dykes), and is overlain by small sporadic microbial buildups and an extensive bioclastic grainstone bed. The deformed limestone was formed during early diagenesis by differential deformation processes (brecciation, liquefaction/fluidization, and injection) which were most likely induced by pore-water overpressure during the period of rapid sea-level fall. Despite the lack of subaerial exposure features (e.g., paleokarst, paleosol, etc.), the characteristics of the erosion surface (cutting well-lithified sediment below), the missing of a significant geological record (the Prochuangia biozone), and the worldwide correlatable positive carbon isotope excursion collectively indicate that the erosion surface developed under conditions of subaerial exposure after contemporaneous marine cementation of the deformed sediment. The missing of the Prochuangia biozone is most likely due to non-deposition at a subaerial hiatal surface. The erosion surface was submerged as a result of subsequent rise in sea level, where sporadic microbial buildups formed under suitable conditions. Freshly deposited, winnowed, shell-dominated transgressive lag deposits (containing Chuangia trilobite fragments, brachiopod shells, and abundant glauconite grains) formed with continued rise in sea level, which became, in turn, overlain by shale-dominated facies. The unique combination of the subtle erosion surface (sensu stricto a subaerial unconformity) and the underlying deformed limestone bed provides an important criterion for recognizing the subtle changes in relative sea level on shallow epeiric platforms. [Copyright &y& Elsevier]

Abstract: Al2O3-modified Li(Ni1/3Co1/3Mn1/3)O2 is synthesized by a modified Al2O3 coating process. The Al2O3 coating is carried out on an intermediate, (Ni1/3Co1/3Mn1/3)(OH)2, rather than on Li(Ni1/3Co1/3Mn1/3)O2. As a comparison, Al2O3-coated Li(Ni1/3Co1/3Mn1/3)O2 also is prepared by traditional Al2O3 coating process. The effects of Al2O3 coating and Al2O3 modification on structure and electrochemical performance are investigated and compared. Electrochemical tests indicate that cycle performance and rate capability of Li(Ni1/3Co1/3Mn1/3)O2 are enhanced by Al2O3 modification without capacity loss. Al2O3 coating can also enhance the cycle performance but cause evident capacity loss and decline of rate capability. The effect of Al2O3 coating and Al2O3 modification on kinetics of lithium-ion transfer reaction at the interface of electrode/electrolyte is investigated via electrochemical impedance spectra (EIS). The result support that the Al2O3 modification increase Li+ diffused coefficient and decrease the activation energy of Li+ transfer reaction but the traditional Al2O3 coating lead to depression of Li+ diffused coefficient and increase of activation energy. [ABSTRACT FROM AUTHOR]

Abstract: This study focuses on the unique occurrence of an extensive microbialite bed (10–20m thick) in the Chaomidian Formation (Furongian) in Shandong Province, China in order to understand its paleoenvironmental implications. The microbialite bed can be traced for over 6000km2 in area. The microbialites are characterized by centimeter- to decimeter-scale branching maze-like constituents (maceriae) of microbial and muddy sediments with chaotic texture, including tabular maceriate microbialite (type 1), columnar maceriate microbialite (type 2), and columnar chaotic microbialite (type 3). Within the bed, each microbialite unit is generally well correlated for tens of kilometers. The entire bed is bounded by limestone–marlstone alternation at the base, and an erosional surface at the top that is subsequently overlain by a grainstone bed of various thicknesses. The microbialite bed formed when the seafloor reached suitable water depth for the microbial growth during sea-level rise accompanied with carbonate production. The maze-like maceria structures formed to acquire a larger surface area under a relatively large input of lime mud. The tabular maceriate microbialites initially formed in relatively deep-water environments and flourished on broad and flat seafloor, whereas the columnar microbialites (types 2 and 3) developed under the influence of strong waves and currents. The microbialite bed was eroded and terminated by frequent storm events and buried under the reworked grainstone. Further rise in sea level and increased metazoan activities afterwards limited the resurgence of microbes in the late Furongian. [Copyright &y& Elsevier]

Abstract: Some examples of a funnel-shaped structure filled with both angular and rounded clasts occur in a peloidal grainstone bed of the Chaomidian Formation (Late Cambrian) in the Jiulongshan area (Shandong Province, China). The clasts consist of peloidal grainstone which is the same as that of the walls of the funnels. The structures are interpreted as dykes formed by upward escape of pore water and/or fluidized sediment through a narrow conduit which was gradually widened by the force of the intruding fluid/sediment. The erosional capacity of the pressurized fluid/sediment mixture consequently diminished upwards, which explains the gradual decrease in intensity of fragmentation from the adjoining walls in this direction. [Copyright &y& Elsevier]

Abstract: A modified Zr-coating process was introduced to improve the electrochemical performance of Li(Ni1/3Co1/3Mn1/3)O2. The ZrO2-coating was carried out on an intermediate, (Ni1/3Co1/3Mn1/3)(OH)2, rather than on Li(Ni1/3Co1/3Mn1/3)O2. After a heat treatment process, one part of the Zr covered the surface of Li(Ni1/3Co1/3Mn1/3)O2 in the form of a Li2ZrO3 coating layer, and the other part diffused into the crystal lattice of Li(Ni1/3Co1/3Mn1/3)O2. A decreasing gradient distribution in the concentration of Zr was detected from the surface to the bulk of Li(Ni1/3Co1/3Mn1/3)O2 by X-ray photoelectron spectra (XPS). Electrochemical tests indicated that the 1% (Zr/Ni+Co+Mn) ZrO2-modified Li(Ni1/3Co1/3Mn1/3)O2 prepared by this process showed better cyclability and rate capability than bare Li(Ni1/3Co1/3Mn1/3)O2. The result can be ascribed to the special effect of Zr in ZrO2-modified Li(Ni1/3Co1/3Mn1/3)O2. The surface coating layer of Li2ZrO3 improved the cycle performance, while the incorporation of Zr in the crystal lattice of Li(Ni1/3Co1/3Mn1/3)O2 modified the rate capability by increasing the lattice parameters. Electrochemical impedance spectra (EIS) results showed that the increase of charge transfer resistance during cycling was suppressed significantly by ZrO2 modification. [Copyright &y& Elsevier]

Abstract: A series of Y2O3:Eu3+ samples with interesting three-dimensional (3D) microarchitectures were synthesized through a facile hydrothermal method in the presence of hexamethylenetetramine (HMT) followed by a subsequent heat treatment. The as-formed precursor via the hydrothermal process could transform to cubic Y2O3 with the same morphology after annealing at 500°C for 2h. The Y2O3 microstructures, with an average diameter about 10–20μm, were composed of nanolamellas with thickness of about 50nm. Besides a probable self-assembly mechanism, the Ostwald Ripening process was proposed to explain the formation of the architectures on the basis of scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observations. The as-synthesized lamella-composed Y2O3:Eu3+ samples showed a strong red emission corresponding to 5D0→7F2 transition (612nm), suggesting promising applications in optoelectronics. [Copyright &y& Elsevier]

• A major climatic cooling episode identified in the earliest Carboniferous. • Cooling coincided with changes in continental weathering and marine productivity. • The expansion of seed floras was a key driver of Early Carboniferous climate change. The expansion of land plants is considered to have played a key role in triggering the Late Paleozoic Ice Age (LPIA), but evidence linking climatic events to terrestrial floral changes is limited. Here, we generated bulk carbonate δ 13C, conodont δ 18O and 87Sr/86Sr profiles from the lowermost Carboniferous of South China and Vietnam in order to investigate their relationship to contemporaneous land plant evolution. Climatic cooling in the mid-Tournaisian coincided with large perturbations to the global carbon cycle and continental weathering regimes as well as with a major diversification episode among seed plants. These relationships are consistent with terrestrial floral changes triggering intensified weathering of basalts (i.e., lower 87Sr/86Sr), enhanced marine productivity (i.e., higher δ 13C carb), and reduced atmospheric p CO 2 and attendant global cooling (i.e., higher conodont δ 18O). The results of our study suggest that expansion of terrestrial floras was a key driver of Early Carboniferous climate change. [ABSTRACT FROM AUTHOR]

Through the Earth's ∼ 4.54 billion year history, icehouse climates have been relatively short-lived but have exerted a significant impact on the evolution of the habitable environment. These icehouse episodes, such as those that occurred in the Cryogenian, mid-Ediacaran, Late Ordovician, and Late Paleozoic, developed through the complex interaction of Earth System processes; however, there is still ongoing debate regarding the causes, processes, and consequences of these glaciations. To improve our understanding of the past history of icehouse climates and the responses of the Earth System, we present this new special issue entitled The Earth System during Icehouse Climate Modes: Contributions from Glacial Records in China. This special issue includes eighteen papers that focus on four major icehouse events: the Cryogenian Snowball Earth glaciations (Sturtian and Marinoan global glaciations), the Ediacaran glaciation, the Ordovician glaciation, and the late Paleozoic Ice Age. This collection of papers provide novel insights into glacial processes, marine environments, and chemical weathering through key intervals of Earth History. We anticipate that this special issue will attract wide interest across the geosciences field. [ABSTRACT FROM AUTHOR]

• Single layer multi-component absorbers with magnetodielectric fillers were synthesized. • Polypyrrole@Ni doped mesoporous carbon was successfully prepared. • The sample with 45 wt% loading exhibits optimal RL characteristics. • RL min of the sample is −13.42 dB with a broad effective bandwidth of 1.18 GHz at 3 mm. • Multiple attenuation of this customized heterogeneous structures enhanced microwave absorption performance. Herein, the polypyrrole coated and Nickel doped mesoporous carbon (MC) composites were synthesized by the Stober and in-situ polymerization methods. Firstly, the carbon mesoporous was derived from silica spheres by impregnated in a water-based solution containing melamine and formaldehyde. Secondly, the nickel doped mesoporous carbon was prepared into the 0.6 g of Ni(NO 3) 2 ·6H 2 O solution and denoted as NiMC. Finally, the core-shell structure composed of NiMC@polypyyrole was synthesized by in situ polymerizations (P@NiMC). The surface characterization results showed that the presence of Ni in mesoporous carbon increased the pore volume, BET surface area and pore size distribution ranges. The dielectric and magnetic properties of MC, NiMC and P@NiMC were measured for the electromagnetic wave absorption performance in the Ku-band. The P@NiMC exhibited better dielectric loss ability compared with MC and NiMC due to the polarization effects. The P@NiMC displayed better electromagnetic wave absorption with a minimum reflection loss of –13.42 dB at 12.4 GHz frequency. In addition, the effective absorption bandwidth (R L < −10 dB) of 1.18 GHz was obtained at a thickness of 3 mm for P@NiMC. This study demonstrated the first report of electromagnetic wave absorption performance of Ni-doped mesoporous carbon which is a promising composite for electromagnetic wave absorption. [ABSTRACT FROM AUTHOR]

The Cambrian SPICE (Steptoean Positive Carbon Isotope Excursion) event is widely reported from the late Miaolingian to the early Furongian, but recent studies imply that the synchroneity and magnitude of the SPICE may be controversial. In order to test the spatial variation of the SPICE, here we present 367 carbonate δ13C data from six outcrop sections across a ~700 km transect along the eastern North China Platform. The SPICE is present in all the studied sections, but showing different features regarding the duration and magnitude. An abrupt increase in δ13C from ~1.5‰ to 3.5‰ occurs in three Shandong sections, with maximum value present only in a thin (0.5–1.2 m thick) transgressive lag deposit (crudely wave stratified, bioclastic grainstone). In contrast, the δ13C record of the Baijiashan and Shashan sections in the Liaoning region displays a gradual increase (~20 m thick) from ~1.5‰ to the maximum value of 4.7‰. Both facies analysis and trilobite collections suggest that the spatial variation of the SPICE in the North China Platform most likely resulted from missing of sedimentary record (with high δ13C values) in the Shandong sections as a result of erosion and non-deposition during sea-level lowstand, a possible coeval hiatus prior to the Sauk III transgression in the Laurentian basins. Further high-resolution, integrated studies of sedimentology, biostratigraphy, and sedimentary geochemistry on the SPICE event are required to better understand its nature. • Six outcrop sections from the eastern North China Platform were studied for SPICE. • A complete SPICE (with max. value of ~4.7‰) was recorded in northeastern NCP. • Spatial variation in SPICE resulted from stratigraphic missing in Shandong region. [ABSTRACT FROM AUTHOR]

Slumps of various scales are recognized in the late Katian (late Ordovician) mixed carbonate and siliciclastic slope successions in the Changshan area, western Zhejiang Province, South China. In order to understand their deformational processes, triggering mechanisms, paleo-slope orientation and geological implications, a detailed sedimentological study was carried out on four outcrop sections. In the southern Changshan (the Putangkou, Zhoutang and Shikeng sections), we recognized three slumping episodes (ca. 3.5 m, 11 m, and 73 m in thickness in stratigraphically ascending order) and co-occurred debris flows. At the Sanqushan section (~11.5 km north of Changshan), thirteen slump units, each being tens of cm to 6 m in thickness, are recognized. Facies analyses and diagenetic characteristics of these slumps and their internal deformation structures suggest that they formed as a result of plastic and brittle deformation, and liquefaction and fluidization during slumping. The rip-up blocks, cracks and ruptured beds in the slumps of southern Changshan indicate extensional features, whereas recumbent and disharmonic folds in the slumps of northern Changshan represent compressional features. These spatially different features suggest that the slumps may have been generated on a paleo-slope dipping generally to the north. The case study of slumps and debris flows from the Putangkou section indicates a significant mass flow transition from a slumped mass into debris flow deposits. Autogenic triggering mechanisms of these slumps, e.g., rapid deposition, storm-wave loading, and tidal shear, are ruled out by the results of facies analysis. Instead, the slumps might have been triggered by relative sea-level changes or tectonically-induced, progressively steepening of the slope, which is likely related to the contemporaneous Kwangsian Orogeny. • Upper Ordovician slump structures and internal SSDS of South China are described. • Tectonically induced steepening of slopes and sea-level changes may be the trigger. • Northward dipping paleo-slope inferred from compressional or extensional features of SSDS. • Sedimentological evidence for Kwangsian Orogeny in South China [ABSTRACT FROM AUTHOR]

Long-lived and extensive glaciation during the Carboniferous and early Permian has been the focus of many studies over the past decade revealing systematic changes in sea level and climatic conditions. The nature of the inception of Carboniferous glaciation, however, remains poorly resolved with uncertainty regarding the timing and dynamics of buildup of continental ice sheets. Here we present detailed sedimentary facies and depositional cycles from Upper Mississippian shallow-water platform and contemporaneous carbonate slope successions from the eastern Paleo-Tethys Ocean region (South China) to reveal systematic variations that provide insight into the sedimentary response to the onset of Carboniferous glaciation. Based on detailed sedimentological logging and facies analysis, four upper Visean cycles and four Serpukhovian cycles were identified from the carbonate platform Yashui section, bounded by either subaerial surfaces or zones, or transgressive surfaces. The cycle tops roughly correspond to intervals rich in normally graded bioclastic wacke- to packstones and with distinct rises (~1‰) in conodont δ18O PO4 in the carbonate slope Naqing section. In particular, the four Serpukhovian cycles correlate well to depositional cycles defined in the Lower Yangtze Platform succession of South China and in the cyclothemic successions in the Donets Basin, Ukraine, suggesting a glacio-eustatic control, most likely caused by repeated advance and retreat of Gondwana glaciation during the onset but prior to widespread glaciation across the mid-Carboniferous boundary. • Facies analysis revealing late Mississippian depositional cycles from South China • Karsted features supporting a middle Brigantian major glacio-eustatic fall • Well-correlated Serpukhovian 1–2 Myr cycles suggesting a glacio-eustatic control [ABSTRACT FROM AUTHOR]

The Devonian System in the Qinghai-Tibetan Plateau and its surrounding areas is widely distributed, diverse in lithotypes and rich in fossils. It records the crucial processes of continuous subduction and reduction of the Paleo-Asian Ocean in the northern hemisphere and the transformation of the Proto-Tethys Ocean into the Paleo-Tethys Ocean in the southern hemisphere. Thus, it is of great significance for explaining the global paleogeographic evolution, tectonic activities and biodiversity changes during this critical period. The blocks on both sides of the southern Tienshan suture zone and the Longmu Co-Shuanghu-Changning-Menglian suture zone belong to different sedimentary systems and paleobiogeographic realms and regions, showing important tectonic paleogeographic partitioning significance. The two suture zones represent the main branches of the Paleo-Asian Ocean and the Paleo-Tethys Ocean, respectively, and on this basis the Devonian System can be subdivided into three types: the Tienshan type, the Tethys type and the Gondwana type. Based on recent research progress on the Devonian stratigraphy and paleontology in combining provenance analysis and biotic characteristics in the Qinghai-Tibetan Plateau and surrounding areas, this paper aims to establish the latest integrative stratigraphic framework and conduct paleogeographic reconstruction, providing foundation for exploring the geological evolution and dynamic mechanisms of various terranes and blocks in the northern margin of Gondwana. The results indicate that the North Qiangtang, South Qiangtang, Simao, Baoshan and Tengchong terranes, as well as the Himalaya Tethys Zone and the South China Block have affinities with the Indian Block, while the Lhasa Terrane has affinities with the Australian Block, and may be located between the South China and Australian blocks. In the Emsian (Early Devonian), the South China Block separated from the northern margin of Gondwana, a process that was accompanied by the opening of the Jinshajiang-Ailaoshan Ocean. In the Middle Devonian, the mid-oceanic ridge of the Paleo-Tethys Ocean expanded rapidly, corresponding with a global sea-level rise, the widespread development of carbonate platforms and nadir values of Devonian seawater strontium isotopes. By the Late Devonian, the Paleo-Tethys Ocean had reached a considerable size, leading to abundant occurrences of Upper Devonian radiolarian cherts in the Paleo-Tethys suture zones. [ABSTRACT FROM AUTHOR]

Transmembrane (TMEM) proteins are integral membrane proteins that traverse biological membranes. Several members of the TMEM family have been linked to the development and progression of various tumors. However, the specific role and mechanism of TMEM44 in tumor biology remain largely unexplored. In this study, we initially conducted an extensive analysis using the TCGA database to investigate the expression patterns and survival associations of TMEM44 across various human tumors. Subsequently, we focused on KIRC and found a significant correlation between TMEM44 expression and this particular cancer type. To validate our findings, we performed western blot and quantitative polymerase chain reaction (qPCR) assays to confirm the expression levels of TMEM44 in KIRC. Following this, we employed a series of functional assays, including CCK8 viability assay, EDU incorporation assay, wound healing assay, and transwell migration assay, to investigate the biological role of TMEM44 in KIRC. We observed a significant upregulation of TMEM44 expression in KIRC, indicating its potential involvement in the pathogenesis of this cancer. We intervened in the expression of TMEM44 in KIRC cells and found significant inhibitory effects on cell proliferation, migration, and invasion in KIRC cells. Furthermore, our findings indicated that TMEM44 could serve as an independent prognostic factor in KIRC, highlighting its potential clinical significance. Consequently, TMEM44 holds promise as both a prognostic biomarker and a prospective therapeutic target for KIRC. [ABSTRACT FROM AUTHOR]

Increasing evidence suggests that therapy-induced senescence (TIS), a novel therapeutic approach in which low doses of therapeutic drugs or radiation are used to induce senescence, suppresses tumor development. Our previous in vitro studies have demonstrated that a low dose of metformin promoted hepatoma cell senescence instead of apoptosis via activation of AMP-activated protein kinase (AMPK) and inactivation of Sirtuin 1 (SIRT1) deacetylase activity. However, the intricate relationship between AMPK and SIRT1, and how they cooperate to induce senescence remains elusive. We showed here that persistent exposure to a low concentration of metformin led to AMPK activation in a mouse xenograft model of human hepatocellular carcinoma (HCC), resulting in senescence. Intriguingly, AMPK counter-regulated SIRT1 via direct phosphorylation in metformin-mediated senescence in hepatoma cells. Taken together, these findings suggest that a low dose of metformin could potentially be used as a TIS-inducing therapeutic drug for HCC, and that this occurs by inducing senescence of HCC cells via the AMPK-SIRT1 pathway. [ABSTRACT FROM AUTHOR]

Earliest Carboniferous stromatolites were found in the Qianheishan (QHS) Formation in the Dashuigou section, Gansu Province, northwestern China. These stromatolites are exposed in a conglomerate‐dominated succession of about 22.5 m in thickness, which can be traced laterally for more than 200 m in outcrop. They consist mainly of micrite, peloids, oncoids, silt‐sized quartz grains, and sparry calcite with rare fine to coarse quartz grains and bioclasts. The occurrence of marine fossils (e.g., bryozoans) and fenestral structures in the stromatolites suggests that they developed in intertidal environments. Three types of stromatolite laminae were distinguished including micritic laminae, grain‐dominated mixed laminae, and micrite‐dominated mixed laminae. These laminae are separated by thin micritic crusts and form two lamination styles of repetitive lamination and alternating lamination. The development of grain‐rich and micrite‐rich laminae in the stromatolites implies that they were formed by the combination of microbial baffling, binding, and calcification. Facies analysis suggests that growth and demise of the stromatolites were controlled by relative sea‐level changes. They grew during a continuous relative sea‐level rise, indicated by variations in their thickness and morphology. Stromatolites change from thin‐bedded laminar forms in the lower part of the studied interval to medium‐bedded wavy‐laminar forms and thick‐bedded domal forms in the middle and upper parts, respectively. Their demise was triggered by dramatic relative sea‐level fall, evidenced from the sandstone facies overlying the stromatolite interval. The occurrence of the QHS stromatolites provides an excellent example for microbial proliferation and profound changes in the marine biosphere after the end‐Devonian Hangenberg extinction event. [ABSTRACT FROM AUTHOR]

• NIRS signals are used in MRI data processing to correct imaging misalignments (referred as "deep synchronization" of both). • Non-sedated functional imaging in a multi-modality framework are performed. • The "deep synchronization" scheme performed better than "post synchronization" of MRI and NIRS. • An eigenfunction model is proposed to quantify the time resolution of the hemodynamic response for temporal co-registration. Periodically rotated overlapping parallel lines with enhanced reconstruction-echo planar imaging (PROPELLER-EPI) is a promising technique for non-sedated functional imaging due to its unique advantage of motion correction. However, its multiple-blades sampling blood-oxygen-level dependent (BOLD) signal leads to low sampling rate and aliasing of higher frequency physiological signal components such as the cardiac pulsation. In this study, we use near infrared spectroscopy (NIRS) synchronized with pulse sequences of PROPELLER-EPI, utilizing the fact that the optical sensing speed is inherently high. NIRS measures changes of oxyhemoglobin and deoxyhemoglobin to identify the transient states of on-BOLD and off-BOLD, and then labels each blade by temporal co-registration. The labeled blades from multiple epochs of a functional experiment are then used for the k -space data combination and subsequent image reconstruction. An eigenfunction model is proposed for temporal co-registration and to quantify the temporal resolution of the hemodynamic response. The experiment of NIRS labeled PROPELLER-EPI was carried out with the optical sampling rate of 10 Hz and the magnetic pulses repetition time of 1000 ms, and the temporal resolution is 20 times better than that of the state-of-the-art sliding-window PROPELLER-EPI. We compared the functional imaging results against the conventional magnetic resonance echo planar imaging-measured activity and achieved an accuracy of 0.9. Using the synchronization of NIRS, the proposed imaging scheme provides an effective way to implement PROPELLER-EPI, which features motion free, high SNR, and enhanced spatial-temporal resolution. [ABSTRACT FROM AUTHOR]

K 2 Zn 3 [Fe(CN) 6 ] 2 @ Ni-P (KNiP) composites with high cesium selectivity were synthesized for the first time. Nickel phosphorus (NiP) was used as a solid base for the adsorption of K 2 Zn 3 [Fe(CN) 6 ] 2 (KZnHCF). The synthesized KNiP composites were characterized by SEM, TEM, XRD, VSM and BET. The characteristic results demonstrated that the composites possess a ball-shape structure, a large surface area of 305.031 m 2 /g and high saturation magnetization of 2.95 emu/g. The ICP-OES analyser was used to determine the concentration of ions in this study. KNiP showed good cesium adsorption performance over a wide pH range and high selectivity for cesium over coexistent competing ions. Analysis of dynamics showed that KNiP has good adsorption performance toward cesium, with an adsorption capacity of 54.95 mg/g. Equilibrium was achieved within only two hours and the experimental data fit the Pseudo second-order model, indicating that the adsorption process was chemisorption. The adsorption process followed the Freundlich isotherm model, indicating that it mainly occured on a heterogeneous surface. [ABSTRACT FROM AUTHOR]

J. Chen, M. Xue, and colleagues report 3D interdigital electrodes based on reduced graphene oxide for stretchable all‐solid‐state supercapacitors with adjustable volumetric capacitance, which are accomplished via pressure spray printing and machine coating. The supercapacitor presented on page 4601 can remain high specific volumetric capacitance while keeping its stretchability, and the specific volumetric capacitance can be adjusted by tuning the thickness of electrode layers. [ABSTRACT FROM AUTHOR]

The Hangenberg Crisis coincided with a large decline of biodiversity and widespread anoxia in the end‐Devonian ocean. Previous research attributed marine anoxia to the spread of deeply‐rooted plants and/or increased volcanism on the continents, but crucial links have not been thoroughly explored. Herein, we propose enhanced weathering as a key trigger, as evidenced by a negative shift (∼8‰) in lithium isotopes and a coupled response in carbon isotopes of marine carbonates in South China. Our findings imply that rapid weathering of crustal rocks increased nutrient delivery to the ocean, as indicated by an increase in the carbonate‐associated phosphate levels, contributing to oceanic eutrophication. In the absence of massive volcanic emissions and intense orogeny, the cause of enhanced continental weathering was likely the expansion of the terrestrial rhizosphere, highlighting the potential for land plant evolution to initiate weathering changes of sufficient severity to trigger a major bio/environmental crisis in the Earth system. Plain Language Summary: The colonization of land plants during the Devonian is believed to have played a key role in regulating Earth's climate. The initially rapid expansion of seed plants into unvegetated or sparsely vegetated uplands is considered to have caused enhanced rock dissolution relative to clay formation on end‐Devonian continents. As a consequence, larger amounts of isotopically‐light lithium were transported to the ocean via rivers, resulting in a distinct negative excursion in seawater lithium isotopes. Concurrently, increased riverine nutrient delivery stimulated marine primary production and thus facilitated the expansion of oceanic anoxia. As a result, drawdown of atmospheric CO2 resulted in climatic cooling, which together with widespread seafloor anoxia, triggered the major biotic turnover known as the "Hangenberg Crisis". Key Points: Negative shift in carbonate lithium isotopes records major enhancement of continental weathering during the end‐DevonianEnhanced chemical weathering increased riverine nutrient delivery and contributed to widespread marine anoxia and the Hangenberg CrisisRapid expansion of seed plants in sparsely vegetated uplands may account for weathering‐driven climatic cooling and oceanic changes [ABSTRACT FROM AUTHOR]