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In order to evaluate rare earth elements (REEs) as a potential proxy for solid bitumen classification, we employed traditional correlation approaches, such as carbon isotopes and V/(V + Ni) ratios, to infer the source rocks of Sinian-Cambrian reservoir solid bitumens in the Sichuan Basin and analyse solid bitumens for their REE compositions by inductively coupled plasma-mass spectrometry. Our data suggested that Sinian-Cambrian reservoir solid bitumens were primarily sourced from the lower Cambrian shales deposited under anoxic-euxinic conditions. REE and their associated parameters seemed to be more sensitive to classify solid bitumens than traditional correlation approaches. REE concentrations played a dominant role and fractionation degree between light and heavy REE and played a secondary role in solid bitumen classification. REE concentration and pattern in solid bitumens might be controlled by two processes, including inheritance from source rocks and water-rock interaction. The major factor controlling REE concentrations in solid bitumens was the type of organic matter of source rocks. Authigenic minerals in solid bitumens formed by water-rock interaction appeared to have little influence on REE compositions of solid bitumens because of their trace contents. Overall, REE could be used as a novel complementary approach to solid bitumen classification in complicated petroleum systems. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This study investigates the influence of expanded perlite (EP) replacement rate and curing methods on the compressive strength of concrete at different ages through the uniaxial compression test. The stress–strain full curve model of concrete considering EP replacement rate is established, and a damage evolution model considering curing conditions, EP replacement rate and load effects is developed based on the damage theory. The results show that: (1) The lack of water in concrete curing will have a huge negative impact on its mechanical properties, and the internal curing effect of pre‐wet EP can effectively alleviate the phenomenon of incomplete hydration. (2) Under dry curing, the addition of EP will reduce the early compressive strength of concrete, while its internal curing effect can improve the compressive strength of concrete in the later stages. (3) The C & C model and the Guozhenhai model are used to construct the segmented model in the rising and falling sections, and the model parameter formula is deduced by the replacement rate. The model can fully describe the stress–strain relationship of expanded perlite concrete (EPC). (4) The damage evolution model of EPC shows an "S" shape growth curve. Dry curing and EP replacement can both reduce the development rate of damage, while the former has a more significant impact. [ABSTRACT FROM AUTHOR]

Ceramic-particle-reinforced iron matrix composites (CPR-IMCs) have been used in many fields due to their excellent performance. In this study, using the fast resistance-sintering technology developed by our team, iron matrix composites (IMCs) reinforced by both SiC and TiCx particles were fabricated via the addition of SiC and Ti3AlC2 particles, and the resulting relative densities of the sintering products were up to 98%. The XRD and EDS analyses confirmed the in situ formation of the TiCx from the decomposition of Ti3AlC2 during sintering. A significant hybrid reinforcing effect was discovered in the (SiC + TiCx)p/Fe composites, where the experimental strength and hardness of the (SiC + TiCx)p/Fe composites were higher than the composites of monolithic SiCp/Fe and (TiCx)p/Fe. While, under the condition of constant particle content, the elongation of the samples reinforced using TiCx was the best, those reinforced by SiC was the lowest, and those reinforced by (SiC + TiCx) fell in between, which means the plastic response of (SiC + TiCx)p/Fe composites obeyed the rule of mixture. The successful preparation of IMCs based on the hybrid reinforcement mechanism provides an idea for the optimization of IMCs. [ABSTRACT FROM AUTHOR]

The characteristics of a tunable Stokes laser based on the cascaded stimulated polariton scattering and stimulated Raman scattering in KTiOPO4 crystal were studied experimentally and theoretically. When the pumping wavelength was 1064 nm, the Stokes laser output wavelength was able to be tuned discontinuously from 1112.08 nm to 1113.64 nm, from 1114.94 nm to 1115.77 nm, and from 1117.37 nm to 1119.92 nm, and the maximum output power appeared at 1118.86 nm. With a pulse repetition frequency of 7 kHz and a pump power of 6.0 W, the maximum output power of the Stokes laser reached 734 mW, and the corresponding diode to laser conversion efficiency was 12.2%. The rate equations describing the temporal evolutions of the fundamental and Stokes waves by noncollinear stimulated polariton scattering and the Stokes wave by collinear stimulated Raman scattering were derived. They were used to simulate the tunable Stokes laser. The calculated results were in agreement with the experimental results on the whole. [ABSTRACT FROM AUTHOR]

Background: We aimed to develop a nomogram that can be combined with point-of-care gastric ultrasound and utilised to predict postoperative nausea and vomiting (PONV) in adult patients after emergency surgery. Methods: Imaging and clinical data of 236 adult patients undergoing emergency surgery in a university hospital between April 2022 and February 2023 were prospectively collected. Patients were divided into a training cohort (n = 177) and a verification cohort (n = 59) in a ratio of 3:1, according to a random number table. After univariate analysis and multivariate logistic regression analysis of the training cohort, independent risk factors for PONV were screened to develop the nomogram model. The receiver operating characteristic curve, calibration curve, decision curve analysis (DCA) and clinical impact curve (CIC) were used to evaluate the prediction efficiency, accuracy, and clinical practicability of the model. Results: Univariate analysis and multivariate logistic regression analysis showed that female sex, history of PONV, history of migraine and gastric cross-sectional area were independent risk factors for PONV. These four independent risk factors were utilised to construct the nomogram model, which achieved significant concordance indices of 0.832 (95% confidence interval [CI], 0.771–0.893) and 0.827 (95% CI, 0.722–0.932) for predicting PONV in the training and validation cohorts, respectively. The nomogram also had well-fitted calibration curves. DCA and CIC indicated that the nomogram had great clinical practicability. Conclusions: This study demonstrated the prediction efficacy, differentiation, and clinical practicability of a nomogram for predicting PONV. This nomogram may serve as an intuitive and visual guide for rapid risk assessment in patients with PONV before emergency surgery. [ABSTRACT FROM AUTHOR]

A tunable ring cavity terahertz parametric oscillator with fixed output direction is reported in this paper. The diamond-shaped Stokes beam resonator was designed for the adjustment of the Stokes beam propagation direction while the propagation direction of pump beam was adjusted by two reflection mirrors. The terahertz wave output direction can be always normal to the output surface by controlling the propagation directions of the pump and Stokes beams cooperatively during the frequency tuning in the range of 1.4–2.4 THz. [ABSTRACT FROM AUTHOR]

• Temperature profiles from new drillings since 2007 are analyzed in details. • The correlations between the mechanisms within the geothermal system and the temperature profiles are identified. • Based on the analysis of temperature data, integrated with other geophysical studies, an updated conceptual model of Olkaria is developed. The Olkaria geothermal system located on the Red Sea - Gulf of Aden - East African Rift high-temperature geothermal belt is a typical rift-volcanic geothermal system. The formation of this system is closely related with lithospheric extension, magmatic intrusion, and hydrothermal activities within the rift. In order to achieve a better understanding of the characteristics and mechanisms within the system, this study analyzes and categorizes the temperature logs from different areas in Olkaria. The impact of the heat sources and heat transfer processes, the permeable structures and flow patterns, as well as the upflow and recharge zones are identified and discussed based on temperature logs. The heat flow state of the Olkaria system is similar to the neighboring Menengai volcano, which could be a compound result of mantle thermal anomaly, magmatic activity, and hydrothermal circulation. The impacts of heat sources are more pronounced in the Olkaria Domes and Olkaria West; while in the Olkaria East and Northeast the hydrothermal redistribution of heat plays a dominant role. The recharge flows are identified along the Suswa fault, the Gorge Farm fault, the Olkaria Fracture, and possibly the southeast periphery of the Domes. Major upflows are found near the center of each producing area. The nature of feed zones within the boreholes and the flow patterns within the geothermal system are discussed. Based on the analysis and comprehensive studies, the characteristics and formation mechanism of the geothermal system are summarized, and an updated conceptual model is proposed. This study can be used as an analog for the exploration and development of high temperature geothermal system in equivalent settings. [ABSTRACT FROM AUTHOR]

Klebsiella pneumoniae carbapenemase 2 (KPC-2) is a serine β-lactamase that can hydrolyze almost all β-lactam antibiotics. The drug resistant problem of bacteria expressing carbapenemases is currently a global problem, therefore, rapid and specific detection of pathogenic bacteria is urgent. In order to obtain an aptamer that can specifically recognize bacteria expressing KPC-2, we have established a method called Precision-SELEX. Precision-SELEX combined protein SELEX and bacterium SELEX. In this method, KPC-2 was used as a target protein, and Escherichia coli expressing KPC-2 (KPC-2 E. coli) was used as a target bacterium. After precision-SELEX, the same aptamer named XK-10 that can recognize KPC-2 and KPC-2 E. coli was obtained while the screening process could be shortened to 4 rounds. Dissociation equilibrium constants were calculated as 0.81 nM by SPR. In addition, XK-10 could specifically bind to KPC-2 E. coli , which was confirmed through flow cytometry and molecular Docking Simulations. The high-content imaging method could detect KPC-2 E. coli. In all, the Precision-SELEX provides an accurate and efficient method to screening aptamers for bacteria. Image 1 • Precision-SELEX can screen aptamers efficiently. • The screening process can be shortened to 4 rounds. • The high-content imaging method can detect KPC-2 E. coli rapidly. [ABSTRACT FROM AUTHOR]

Abstract Shallow water delta developed during the Late Cretaceous greenhouse climate depositing in the red bed succession of the Yaojia Formation in the Southern Songliao Basin, NE China. The shallow water delta deposits provide an opportunity to understand the influence of high discharge variability in a semi-arid climate on the fluvial patterns, internal sedimentary details, and reservoir quality of distributary channels. The sedimentary process of the shallow water delta in the Yaojia Formation was controlled by a dual-stage process, including a high-flow stage and a low-flow stage within a semi-arid paleoclimate. During the high-flow stage, crevasse channels formed through avulsion of major distributary channels on the delta plain. Subaqueous terminal distributary channels and mouth bars formed at the delta front during progradation of the delta. During the low-flow stage after flood events, crevasse channels were abandoned and frequently exposed becoming reddish in color. This process can be reason for the classification for two main types of distributary channels: major distributary channels and crevasse channels in the delta plain. Sand bodies in distributary channels are distinguished by sedimentary structures indicate critical and supercritical flow conditions. Based on well logs and 3D seismic data, the sand distribution of was analyzed from the sandstone isopach map of the 2nd sand bed in the first member of the Yaojia Formation. The framework sand belts develop coincides with distribution of the major distributary channels. Based on detailed observational and reservoir test data from cores, the distribution of major distributary channels revealed a belt of high-quality reservoirs in the shallow water delta. This study provides a new perspective on the sedimentary pattern of distributary channels in shallow water deltas with high discharge variability, which has important implications for reservoir exploration in lacustrine basins. Highlights • Sedimentary characteristics of a shallow water delta recorded in the Late Cretaceous red bed succession. • Sedimentary pattern of distributary channels of shallow water delta with high discharge variability in semi-arid climate. • Sedimentary patterns of distributary channels lead to significant variance in reservoir properties. [ABSTRACT FROM AUTHOR]

In the Precambrian dolomites in the central Sichuan Basin, a substantial paleo-oil system previously existed, which has since evolved into a dry gas system that is currently in place. The genesis of this paleo-oil system remained poorly understood, leaving uncertainties regarding the timing of oil charging and associated source rocks. Integration of Re–Os geochronometry with basin modeling allows temporal-spatial constraints on the ancient petroleum system to be established. Two texturally distinct generations of reservoir bitumen were identified. Late-generation bitumen yielded a geologically meaningful Re–Os age of 189 ± 20 Ma (MSWD = 10.4, 2σ), distinct from the previously documented Re–Os ages such as the 414 ± 44 Ma reported by Shi et al. (2020). This new age, along with the ∼414 Ma, aligns within uncertainties with the two relative timings derived from our independent basin model (ca. 450–390 Ma and 260–180 Ma), revealing two temporally distinct oil generation-migration events. The date of ∼189 Ma also lends support to the previous oil charge timing inferred from fluid inclusions. We evaluated the imprecisions of these two Re–Os ages and considered them to result from a narrow spread in 187Re/188Os, and variations in initial Os isotopic compositions (Os i) due to the giant size of the petroleum system and a long duration of oil generation from source kitchen over a large geographical area in this play. Effects of asphaltene precipitation, due to uplift-induced decompression of the migrating oils, may also have contributed to the scatter. Separating the samples based on Os i produced a higher precision age (184.1 ± 5.7 Ma, Model 1) with an MSWD of 0.97. The first oil charge is relatively weak as shown by the basin model and observed bitumen volumes, and it had not been well preserved due to significant reservoir exhumation by Caledonian tectonism. Consequently, the younger oil charge is considered to be the principal precursor to the current dry gas accumulations. Os isotope histories for four potential source units were constructed using publicly available Re–Os data. Comparisons between bitumen and rock Os compositions tend to support the lower Cambrian Qiongzhusi Formation as the predominant source unit for the two major paleo-oil charges. However, contributions from the Duoshantuo, Dengying, and Maidiping source rocks can not be precluded. Overall, these new observations allow temporal-spatial constraints to be placed on the complex evolution, from paleo-oil generation to destruction and dry gas generation. • Two paleo oil charges sourced from the lower Cambrian Qiongzhusi shales. • Agreement between two bitumen Re–Os ages and modeled oil generation stages. • Assessing the precision limitations of hydrocarbon Re–Os ages. [ABSTRACT FROM AUTHOR]

Economically viable accumulations of hydrocarbons hosted in the Precambrian rocks are globally rare, as a protracted history available for them to escape or be destroyed due to various processes including thermal and bacterial degradations and tectonic disruption. A recent gas discovery in the late Ediacaran dolomites of the Sichuan Basin (SW China) provides an opportunity to understand the formation and preservation of ancient petroleum systems. Paleo fluid pressure-temperature-composition (P-T-X) conditions from deep burial to exhumation are evaluated from microthermometry and Raman data obtained from fluid inclusions. We identified three texturally distinct generations of gas-bearing fluid inclusion assemblages (FIAs), which delineate an operating petroleum system where gas remigrated during exhumation that followed oil cracking during deep burial. The older FIAs (types 1 and 2) show a petrographic association with bitumen and are interpreted to be the result of thermal cracking. Type 1 FIAs formed through in-situ cracking of pre-existing oil inclusions and have recorded the paleo oil charge during the middle Triassic to early Jurassic. Type 2 FIAs were trapped during the prolonged intra-reservoir oil cracking that occurred between the late Jurassic and late Cretaceous. Our pore pressure calculations indicate overpressured conditions, a result of active gas generation during thermal cracking. Lithostatic overpressures accumulated and were sustained under weak tectonic compression prior to peak burial. Type 3 FIAs have been interpreted as reflective of the gas-bearing system reactivation during exhumation. These FIAs indicate the relative reduction in the proportion of aqueous to gas inclusions, which may be due to a decrease in water saturation following gas emplacement. Uplift processes during early exhumation likely facilitated breaching of the system and remobilization of fluids, resulting in gas escape and overpressure release. The drastic increase in formation water salinity, which was documented in the fluid inclusion dataset, points to the arrival of hypersaline brine during the Eocene to Oligocene. This brine could have originated either from the lower Cambrian evaporated CaCl 2 seawater or from the dissolution of the lower-middle Triassic halite. From the late Miocene to present, progressively exhumed reservoirs may have received an influx of relatively fresh water from shallow aquifers, as shown by the correspondence between P-T-X records and present-day reservoir conditions. • Fluid PTX history of ancient petroleum systems. • Exhumation-driven remigration of gas following thermal cracking of deeply buried oil. • Openness of basin fluid systems induced by tectonic uplift. [ABSTRACT FROM AUTHOR]

In order to understand redox variations and organic matter accumulation on the Yangtze carbonate platform during the Late Ediacaran–Early Cambrian, petrological and geochemical studies of several wells were carried out in this work. Our data suggest that depositional environments were dominated by oxidizing bottom water conditions during the late Ediacaran, and evolved to anoxic conditions, triggered by blooms of microbial organisms in surface waters during the earliest Cambrian. Subsequently, massive release of H 2 S derived from both anaerobic recycling of organic matter and, probably, hydrothermal venting promoted a sulfidic ocean. The discovery of a Ni-Mo sulfide ore layer in the basal Cambrian implies that such a sulfidic condition spread onto the Yangtze carbonate platform interior during the late Cambrian Stage 2. Further, transgressive flooding led to widespread black shale deposition and persistently anoxic conditions, as indicated by geochemical proxies. During the late Ediacaran to earliest Cambrian, local and widespread phosphogenesis indicates that organic matter accumulation was intimately associated with microbial (especially cyanobacterial) blooms driven by phosphorus cycling. The organic matter accumulations in early Cambrian black shales, however, were in connection with anoxic bottom water conditions and intermittent replenishment of recycled organic phosphorus to surface waters. [ABSTRACT FROM AUTHOR]

• Multi-stage dolomite cementation was related to tectonic events. • Dolomite U-Pb ages constrain on timings of two paleo-oil charge episodes. • Two episodes of hydrothermal events with different causes. Improved understanding of subsurface paleo-fluid circulation history can assist in reconstructing associated pore evolution of carbonate reservoirs. Multi-stage dolomite cements generated by basinal fluids over time were investigated using a combination of petrography, geochemistry, fluid-inclusion studies, LA-ICP-MS U-Pb geochronology, and seismic interpretation. This study aims to gain clues about diagenetic, hydrothermal and paleo-oil filling events within the Ediacaran Dengying Formation, Sichuan Basin, China. Four main phases of dolomite cementation were petrographically, geochemically and geochronologically distinguished that can be ascribed to major tectonic events throughout the basin evolution. The earliest dolomite generation occurs as fibrous dolomite crust (FDC) growing along the karst vug wall, interpreted as marine diagenetic cement formed in a submarine environment during the Late Ediacaran, most likely from the influx of seawaters following the uplift and subaerial exposure related to the Tongwang movement. In situ U-Pb ages obtained from the other three generations of cement dolomites are interpreted to coincide with the timing of repeated strike-slip fault movements as indicated by the seismic data, suggesting a direct link between cement emplacement and regional tectonic-thermal events. Sub-vertical extension dolomite veins (EDV), representing the second generation, are considered as being syntectonic, generated from slightly modified connate seawaters at a shallow to moderate burial depth in a transtensional stress regime during the Cambrian taphrogenesis. Two generations of saddle dolomite cements, SD1 and SD2, have recorded two major episodes of hot fluids circulating in the Dengying Formation. The SD1, filling in hydraulic fractures and vugs, formed during the third phase of cementation, as a result of a hydrothermal event associated with Caledonian exhumation. Deep-seated hot brines squeezed into the Dengying reservoirs along the sub-vertical strike-slip faults combined with some meteoric waters that percolated downward, are deemed responsible for precipitating SD1. The SD2 is the youngest cement present, which is interpreted to have formed during the ingress of deeper, hot, hypersaline brines arising from the late Permian hydrothermal activity likely triggered by the eruption of Emeishan flood basalts. Cross-cutting relationships between bitumen phases and different dolomite generations indirectly define the dates of two paleo-oil charging events. The first episode of paleo-oil charging occurred during the Late Ediacaran to Early Cambrian, likely sourced from underlying Ediacaran Doushantuo shales. Late oil emplacement occurred after the Late Permian, in agreement with the reported bitumen Re-Os age and the age inferred through fluid-inclusion analysis. Primary source rocks generating this phase of oil were considered as the Cambrian Qiongzhusi shales, because basin modeling-derived date of oil window matches with the second oil filling time. [ABSTRACT FROM AUTHOR]

• Part of uppermost basement in the West Kunlun Orogen is early Paleozoic. • Arc-related magmatism in the West Kunlun Orogen continuous during early Paleozoic. • Subduction retreating during Neoproterozoic and advancing during early Paleozoic. • Advancing subduction at 540–420 Ma likely responsible for closure of Proto-Tethys Ocean. The West Kunlun Orogenic Belt (WKOB) is a key area for evaluating the evolution of the Proto-Tethys Ocean. To constrain this history, we present geochemical and zircon U-Pb geochronological data from a suite of metasedimentary rocks within this orogenic belt. Detrital zircons ages are clustered between 1000 and 400 Ma, with major peaks at ca. 510 Ma and 460 Ma, and minor peaks at ca. 840 Ma and 650 Ma. The age groups younger than 1000 Ma broadly overlap magmatic activity at ca. 540–420 Ma and minor magmatism at 920–540 Ma in the WKOB. The age data also reveal Early Paleozoic metamorphic basement rocks in the WKOB that were probably sourced from Kunlun terranes and blocks of Gondwanan affinity rather than the Tarim Craton. Compiled geochemical data suggest a protracted subduction setting in the WKOB in the Early Paleozoic. εHf(t) values show increasing trends at 900–740 Ma and 740–600 Ma and a distinct decreasing trend at 540–420 Ma, consistent with retreating subduction during the Neoproterozoic and advancing subduction in the Early Paleozoic. The retreating-advancing subduction cycle in the WKOB was possibly related to the opening and closure of the Proto-Tethys Ocean along the margin of Gondwana. [ABSTRACT FROM AUTHOR]

• Present-day gas reservoirs evolved from paleo-oil reservoirs via thermal cracking. • Gas generation took place at ca. 154 ± 21 Ma as suggested by pyrobitumen Re-Os dating. • Dolomite U-Pb age is correlated in timing with eruption of Emeishan flood basalts. • Paragenesis, coupled with fluid inclusion, constrains the time of paleo-oil filling. Primary gas accumulation with trillions of cubic meters of gas volumes was discovered recently in the Precambrian Dengying Formation of the Gaoshiti-Moxi block, Central Sichuan Basin, China. In this study we investigated the pervasive saddle dolomite cements and solid bitumens within karst vugs in the Dengying dolomite reservoirs. Using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) in situ U-Pb dating, we obtained a high-precision absolute age of 259.4 ± 3.0 Ma for the saddle dolomite cementation, consistent in timing with the eruption of Emeishan flood basalts (262–251 Ma). Combined with high homogenization temperatures (Th) and salinities of primary fluid inclusion, as well as rare earth element (REE) compositions, we consider that the saddle dolomite precipitation was likely related to hydrothermal activity driven by the Emeishan mantle plume. The identification of rare surviving oil inclusions and extensive solid bitumens within the dolomite vugs is indicative of the presence of paleo-oil reservoirs. These bitumens are characterized by high equivalent vitrinite reflectance (R equ), no fluorescence, and deformed fibrous textures, typical of highly mature pyrobitumens. Gas geochemistry data indicates that only minor thermochemical sulfate reduction (TSR) has occurred. Thus the pyrobitumen was interpreted to result mainly from the thermal cracking of paleo-oils, and its associated Re-Os isochron age of 154 ± 21 Ma, representing the timing of dry gas formation. Petrographical evidence suggests that the paleo-oil charge must have taken place after sparry dolomite cementation but prior to pyrobitumen generation. This, combined with coeval aqueous inclusion Th data and published thermal-burial models, constrains the time of paleo-oil emplacement to ca. 222–205 Ma, suggesting an oil-filling event related to the Indosinian Orogeny. This study documented the first chronological data constraining the complex evolution history of a petroleum system in one of the oldest primary gas reservoirs in the world. [ABSTRACT FROM AUTHOR]

The Meso-Neoproterozoic period, sometimes referred to as the 'boring billion' or 'Earth's middle age', spans the interval between the formation of the Columbia and Rodina supercontinents. It is regarded as a stable era of the Earth. However, from a global perspective, there are many intensive events of mafic volcanism, dyke intrusions and formation of rift basins recorded in different cratons during this period. This paper focuses on rift basins that developed in three cratons in China (North China, South China and Tarim cratons), because large-scale primary gasfields, as one of the deep resources, have been discovered recently in rocks of Meso-Neoproterozoic age. The formation mechanisms and tectonic settings of these rift basins as the targets of Deep Earth are discussed, based on the restoration of global positions of the three cratons by pre-existing paleomagnetic data and plate reconstruction. We recognise that the rift basins of the North China Craton are related to extrusion tectonics in the southwest Ordos Block or are pull-apart basins along the northern and southern sides of the Ordos Block. The rift basins of the South China Craton are derived from mantle lithospheric delamination of the Jiangnan Orogen in the eastern South China Craton or subduction retreat and backarc opening in the western South China Craton, respectively. The rift basins of the Tarim Craton originated from the backarc opening along the margin of the Supercontinent Rodinia. [ABSTRACT FROM AUTHOR]

• Meso-Cenozoic tectonism deformed the Meso-Neoproterozoic differently in the NCC. • They showed both constructive and destructive effects on Meso-Neoproterozoic traps. • Both Meso-Neoproterozoic and Cenozoic hydrocarbons still have potentials in the NCC. As the first extensively developed sedimentary cover in the North China Craton (NCC), the thick Meso- to Neoproterozoic strata have great exploration potential for hydrocarbons. However, the Meso-Cenozoic Indosinian, Yanshanian and Himalayan movements caused the Meso-Neoproterozoic strata in the NCC to experience various deformations and even destroyed Meso-Neoproterozoic primary oil-gas reservoirs, especially their trap conditions. Until now, how each Meso-Cenozoic tectonic movement influenced the development and evolution of Meso-Neoproterozoic oil-gas traps in different parts of the NCC has remained unclear. The Indosinian Movement caused Meso-Neoproterozoic rocks to undergo gentle folding, as well as limited thrusting, and mainly brought about the creation of contractional anticlinal traps in the NCC. In contrast, the early Yanshanian Movement mainly triggered their vertical movement and may have introduced some stratigraphic and faulted-related traps. The middle Yanshanian Movement led to the Meso-Neoproterozoic strata being involved in more intense differential folding, thrusting and strike-slip faulting in the western, central, and eastern NCC, at the cost of destroying the earlier-formed structures, especially those in the central-eastern NCC. Thus, the mid Yanshanian Movement showed both constructive and destructive effects on the formation and evolution of the Meso-Neoproterozoic oil-gas traps and made them develop incoherently in different parts of the NCC. The late Yanshanian and Himalayan movements did not affect the Meso-Neoproterozoic strata in the western NCC, but caused those in the middle NCC to be uplifted and eroded further, whilst strata in the eastern NCC became inverted, subsided and buried. As a consequence, it led to the continuous destruction of the Meso-Neoproterozoic structural-related traps for Meso-Neoproterozoic primary hydrocarbons in the central-eastern NCC, and the formation of the Meso-Neoproterozoic buried-hill traps for Cenozoic hydrocarbons in the eastern NCC. Based on our structural analysis, it is suggested that the Meso-Neoproterozoic primary hydrocarbons could have accumulated in various Meso-Neoproterozoic structural-related traps with the overlying well-preserved Paleo-Mesozoic strata, especially, those in the southwest Ordos Basin. The promising Meso-Neoproterozoic buried-hill traps for Cenozoic hydrocarbons are mainly located in the western Bohai Bay Basin and the south part of the southern North China Basin. [ABSTRACT FROM AUTHOR]

This paper delves into the engineering applications of lime-stabilized red clay, a highly water-sensitive material, particularly in the context of the climatic conditions prevalent in the Dalian region. We systematically investigate the impact of water content, dry density, and freeze-thaw cycles (with a freezing temperature set at -10°C) on the thermal conductivity of stabilized soil, a crucial parameter for analyzing soil temperature fields that is influenced by numerous factors. By developing and validating both empirical and machine learning prediction models, we unravel the evolution of thermal conductivity in response to these factors: within the range of influencing variables, thermal conductivity exhibits an exponential or linear increase with rising water content and dry density, while it decreases exponentially with increasing freeze-thaw cycles. Furthermore, we quantitatively analyze the specific influence of water content and other factors on the thermal conductivity of stabilized soil and construct a comprehensive prediction model encompassing BP neural network, gradient boosting decision tree, and linear regression models. Comparative analysis highlights the significant enhancement in prediction accuracy achieved by the proposed ensemble model over single machine learning models, with root mean square error (RMSE) values below 0.05 and mean absolute percentage error (MAPE) values remaining under 2.5% in both frozen and unfrozen states. Additionally, a secondary validation using experimental data from other researchers confirms the model's good agreement with previous results, demonstrating its robust generalization ability. Our findings provide valuable insights for engineering studies in the Dalian region and red clay areas subjected to extreme climatic conditions., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Wang et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Premature ovarian failure (POF) is a disease that seriously jeopardizes women's physical and mental health worldwide. Zisheng Tongmai decoction (ZSTMD), a famous Traditional Chinese Medicine (TCM) formula, has a marked effect on the clinical treatment of POF. This study investigated the potential mechanism of ZSTMD to improve POF through network pharmacology and experimental validation. The active components, key targets and potential mechanisms of ZSTMD against POF were predicted by network pharmacology and molecular docking. The POF model was induced in rats by cyclophosphamide (CTX) and subsequently gavaged with different doses of ZSTMD. KGN cells were treated with different concentrations of quercetin and CTX. Histopathological were observed via hematoxylin and eosin (H&E) staining and immunofluorescence staining. Serum estrogen levels were detected via ELISA. Protein expression was detected via Western blot. We identified quercetin as the main active ingredients targeting VEGFA. Molecular docking showed that VEGFA interacted well with the main active components of ZSTMD. In vivo experiments, ZSTMD significantly increased body weight and the ovarian index, significantly increased E2 and AMH, and decreased FSH and LH in POF rats. Histologic results showed that ZSTMD increased the number of follicles and vascular density in the ovary. It also increased VEGFA and CD31 protein expression. In vitro experiments, quercetin suppressed CTX-induced apoptosis in KGN cells and increased VEGFA protein expression. Our study demonstrated that ZSTMD improves POF by promoting angiogenesis through VEGFA target., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Objective: To develop and validate a predictive model for sarcopenia., Methods: A total of 240 subjects who visited our hospital between August 2021 and May 2023 were randomly divided by time of entry into a training set containing 2/3 of patients and a validation set containing 1/3 of patients. The muscle thickness (MT), echo intensity (EI), and shear wave velocity (SWV) of the medial gastrocnemius muscle were measured. Indicators that were meaningful in the univariate analysis in the training set were included in a binary logistic regression to derive a regression model, and the model was evaluated using a consistency index, calibration plot, and clinical validity curve. Diagnostic efficacy and clinical applicability were compared between the model and unifactorial indicators., Results: Four meaningful variables, age, body mass index (BMI), MT, and SWV, were screened into the predictive model. The model was Logit Y = 21.292 + 0.065 × Age - 0.411 × BMI - 0.524 × MT - 3.072 × SWV. The model was well differentiated with an internally validated C-index of 0.924 and an external validation C-index of 0.914. The calibration plot predicted probabilities against actual probabilities showed excellent agreement. The specificity, sensitivity, and Youden's index of the model were 73.80%, 97.40%, and 71.20%, respectively, when using the diagnostic cut-off value of >0.279 for sarcopenia. The logistic model had higher diagnostic efficacy (p < 0.001) and higher net clinical benefit (p < 0.001) over the same threshold range compared to indicators., Conclusion: The logistic model of sarcopenia has been justified to have good discriminatory, calibrated, and clinical validity, and has higher diagnostic value than indicators., Competing Interests: Conflict of interest The authors declare no competing interests., (Copyright © 2024 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.)

In Northwest China, the highway infrastructure often faces challenges due to the widespread presence of subgrade soil. This soil undergoes significant changes in performance under cyclic loading and freeze-thaw cycles. To effectively design and construct highways in these regions, it is crucial to understand the impact of various factors on the deformation characteristics and mechanical properties of subgrade soil. This study aims to investigate the influence of freeze-thaw cycles, water content, confining pressure, and loading rate on the deformation behavior and mechanical properties of subgrade soil under cyclic loading conditions. Experimental tests were conducted to analyze the deformation characteristics and mechanical properties of the subgrade soil. The test results revealed the following: 1) Dynamic loading leads to a noticeable decrease in the strength of subgrade soil, resulting in a softening effect on the stress-strain curve. The cumulative strain of the soil is positively correlated with the number of freeze-thaw cycles and water content, while negatively correlated with confining pressure. The final cumulative strain remains below 1%. 2) The failure stress of subgrade soil decreases exponentially with an increase in freeze-thaw cycles, dropping from 224.52 kPa to 196.76 kPa. 3) An increase in water content linearly decreases the failure stress of subgrade soil, ranging from 377.1 kPa to 151.5 kPa. 4) Confining pressure exhibits a linearly increasing relationship with the failure stress of subgrade soil, ranging from 151.6 kPa to 274.5 kPa. 5) The failure stress of subgrade soil demonstrates a linear increase with the loading rate, ranging from 200.46 kPa to 210.62 kPa. These findings provide valuable insights for the design and construction of highways in seasonal frozen areas. They also offer guidance for preventing and mitigating subgrade freeze-thaw issues in the future., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Li et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

In recent years, optical tweezers have become an effective bioassay tool due to their unique advantages, especially in combination with suspension beads, which can be applied to develop a high-performance analysis platform capable of high-quality imaging and stable signal output. However, the optical tweezer-assisted bead analysis is still at the early stage, and further development of different favorable methods is in need. Herein, we have first developed the optical tweezer-assisted immuno-rolling circle amplification (immuno-RCA) on beads for protein detection. Prostate-specific antigen was selected as the model analyte, and the immunosandwich structure on beads was built by the high affinity of "antibody-antigen". The "protein-nucleic acid" signals were effectively converted through the covalent coupling procedure of antibodies and oligonucleotides, further initiating the RCA reaction to achieve signal amplification. The individual beads with the strong irregular Brownian motion in a fluid environment were eventually trapped by the optical tweezers to acquire the accurate and high-quality signal. Compared with the conventional immunoassay on beads, the sensitivity of the developed strategy was increased by 587 times with a limit of detection of 4.29 pg/mL (0.13 pM), as well as excellent specificity, stability, and reproducibility. This study developed the new optical tweezer-assisted beads imaging strategy for protein targets, which has great potential for being applied to clinical serology research and expands the application of optical tweezers in the bioassays.

In this study, phase change materials (PCMs) were innovatively incorporated into hybrid fiber concrete. The properties of PCMs, which absorb and release heat during phase transitions, enable the concrete to actively respond to complex and varying temperature environments. This integration reduces the internal temperature differentials within the concrete, thereby preventing temperature-induced cracks in deep wellbore structures. Through the temperature control model test of the frozen shaft wall, it can be seen that the hybrid fiber phase change concrete (HFPCC) significantly reduces the internal temperature difference, and the maximum temperature difference along the radial direction is 35.84% lower than that of benchmark concrete (BC). The numerical simulation results indicate that a moderate phase transition temperature should be selected in engineering. The phase change temperature should not be close to the ambient temperature and peak temperature. The peak temperature can be reduced by 9.32% and the maximum radial temperature difference can be reduced by 30.89% by selecting an appropriate phase change temperature. The peak temperature and radial maximum temperature difference are both proportional to the latent heat of phase change. The temperature control performance of phase change concrete can be further improved by increasing the latent heat of phase change materials., Competing Interests: All authors declare that they have no competing interests related to the content of this manuscript. We have ensured objectivity and impartiality in conducting and reporting our research., (Copyright: © 2024 Li et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)