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The Mississippi Valley–type (MVT) deposits reached their maximum abundance during the final assembly of Pangea. The intense orogenic activity during this assembly in relatively low latitudes created abundant opportunities for the migration of sedimentary brines into the interior carbonate platforms landward of the orogenic belts, leading to the formation of MVT deposits. Thus, dating the MVT deposits can potentially aid in the reconstruction of the plate tectonic evolution during the assembly of Pangea. The Yangtze Craton hosts significant carbonate-hosted Zn–Pb deposits (> 60 Mt Pb + Zn metals), accounting for 30% of China's Zn–Pb resources. However, determining the timing of zinc and lead mineralization in these reservoirs is challenging. This study employs LA-ICP-MS U–Pb geochronology on calcites to date Zn–Pb deposits hosted in Lower Cambrian limestone in the Huayuan orefield. Three generations of calcite formation were dated: the first recorded the pre-ore deposition of Lower Cambrian limestone at 517 ± 10 Ma, the second marked a hydrothermal event linked to stratiform sphalerite ore formation at 501.4 ± 8.4 Ma, and the third was associated with discordant breccia-hosted Zn–Pb mineralization at 397.5 ± 9.6 Ma. Our results indicate that Paleozoic carbonate-hosted Pb–Zn mineralization in the Yangtze Craton is linked to (1) the final assembly of Gondwana in the late Cambrian-early Ordovician (520–480 Ma); and (2) the intracontinental orogeny response to Jiangnan Uplift (420–400 Ma). This study highlights the temporal relationship between low temperature carbonate-hosted mineralization and orogenic events that are consistent with classic MVT models worldwide. It also contributes geochronological data for the reconstruction of plate-tectonic evolution during Pangea assembly. Furthermore, it demonstrates the potential of in situ U–Pb calcite geochronology to date ore deposits lacking syn-ore minerals suitable for traditional dating methods. [ABSTRACT FROM AUTHOR]

Introduction: The commonly used clinical indicators are not sensitive and comprehensive enough to evaluate the early staging of chronic kidney disease (CKD). This study aimed to evaluate the differences in arterial spin labeling (ASL) and blood oxygenation level–dependent functional magnetic resonance imaging (BOLD-MRI) parameter values among patients at various stages of chronic kidney disease and healthy individuals. Methods: Electronic databases PubMed, Web of Science, Cochrane, and Embase were searched from inception to March 29, 2024, to identify relevant studies on ASL and BOLD in CKD. The renal blood flow (RBF) and apparent relaxation rate (R2*) values were obtained from healthy individuals and patients with various stages of CKD. The meta-analysis was conducted using STATA version 12.0. The random-effects model was used to obtain estimates of the effects, and the results were expressed as 95% confidence intervals (CIs) and mean differences (MDs) of continuous variables. Results: A total of 18 published studies were included in this meta-analysis. The cortical RBF and R2* values and medulla RBF values were considerably distinct between patients with various stages of CKD and healthy controls (MD, − 78.162; 95% CI, − 85.103 to − 71.221; MD, 2.440; 95% CI, 1.843 to 3.037; and MD, − 36.787; 95% CI, − 47.107 to − 26.468, respectively). No obvious difference in medulla R2* values was noted between patients with various stages of CKD and healthy controls (MD, − 1.475; 95% CI, − 4.646 to 1.696). Conclusion: ASL and BOLD may provide complementary and distinct information regarding renal function and could potentially be used together to gain a more comprehensive understanding of renal physiology. [ABSTRACT FROM AUTHOR]

The largest ever primate and one of the largest of the southeast Asian megafauna, Gigantopithecus blacki1, persisted in China from about 2.0 million years until the late middle Pleistocene when it became extinct2–4. Its demise is enigmatic considering that it was one of the few Asian great apes to go extinct in the last 2.6 million years, whereas others, including orangutan, survived until the present5. The cause of the disappearance of G. blacki remains unresolved but could shed light on primate resilience and the fate of megafauna in this region6. Here we applied three multidisciplinary analyses—timing, past environments and behaviour—to 22 caves in southern China. We used 157 radiometric ages from six dating techniques to establish a timeline for the demise of G. blacki. We show that from 2.3 million years ago the environment was a mosaic of forests and grasses, providing ideal conditions for thriving G. blacki populations. However, just before and during the extinction window between 295,000 and 215,000 years ago there was enhanced environmental variability from increased seasonality, which caused changes in plant communities and an increase in open forest environments. Although its close relative Pongo weidenreichi managed to adapt its dietary preferences and behaviour to this variability, G. blacki showed signs of chronic stress and dwindling populations. Ultimately its struggle to adapt led to the extinction of the greatest primate to ever inhabit the Earth.A multiproxy record of Gigantopithecus blacki provides insights into the ecological context of this species, which became extinct around 250,000 years ago, when increased seasonality led to a change in forest cover. [ABSTRACT FROM AUTHOR]

Radiogenic isotope dating of illitic clays has been widely used to reconstruct thermal and fluid flow events in siliciclastic sedimentary basins, the information of which is critical to investigate mechanisms of hydrocarbon maturation. This study carried out Rb−Sr and 40Ar−39Ar dating of authigenic illitic clay samples separated from the Palaeogene sandstone in the northern South China Sea. Our Rb−Sr data further confirm the previously reported three periods of fluid flow events (at 34.5 ± 0.9, 31.2 ± 0.6, and 23.6 ± 0.8 Ma, respectively) in the northern South China Sea, which are related to regional episodic tectonism. However, 40Ar−39Ar ages of illite obtained in this study are significantly younger than the corresponding Rb−Sr ages. The significantly younger 40Ar−39Ar ages were probably due to 40Ar loss caused by later dry heating events on the Hainan Island that have not affected the Rb−Sr isotopic systematics. The inconsistency between Rb−Sr and 40Ar−39Ar data should be attributed to different isotopic behaviors of K−Ar and Rb−Sr isotopic systematics in illite. Our results indicate that Rb−Sr isotopic dating method may be a preferential approach for clay dating in geological settings where exist younger dry heating events. [ABSTRACT FROM AUTHOR]

Coral reefs are experiencing a dramatic loss of hard coral abundance and associated habitat structure from a myriad of local and global factors. Here, utilizing U–Th radiometric age-dating of coral death assemblages, we investigated patterns of coral mortality from the eastern margin of the Red Sea along a latitudinal gradient (Yanbu, 24o N; Thuwal, 22o N; Al-Lith, 19o N; Farasan Banks, 18o N) in 2018 and 2019. In all four regions, radiometric ages of in situ dead Acropora and Pocillopora colonies were largely confined to the late twentieth and early twenty-first century. During the early twenty-first century, coral mortality was found to be synchronous with previously documented bleaching events in 2010 and 2015 and, at one site (Farasan Banks), an outbreak of crown-of-thorns starfish (COTS) in 2009. The most northern site, Yanbu, had the highest relative percentage of live coral (42 ± 4%) and of living Acropora, and may serve as a refugium under climate warming scenarios. For the three southern regions (Thuwal, Al-Lith, Farasan Banks) benthic structure was mostly comprised of dead corals. The southernmost survey site, Farasan Banks, underwent a dramatic change in coral benthic structure associated with a COTS outbreak in 2009 and a bleaching event in 2015, and had the lowest relative percentage of live coral (6 ± 2%), comprised mostly of massive Porites, with no live Acropora or Pocillopora. Our results highlight the asynchronous impact of disturbance events on eastern Red Sea coral reefs and emphasize regional differences in recovery and ecosystem state. [ABSTRACT FROM AUTHOR]

Two types of potash ores were sampled from the Mengyejing potash deposit (the MPD) which is the only ancient potash deposit ever found in China. Geochemical analyses, including Br, K, Mg and some heavy metals, were performed on those samples. The relatively consistent Br contents (141.42 to 763.67 ppm) in both bedded potash and veined potash ores show that the potash-forming brine was likely derived from seawater. K contents and Br/Cl ratios of the veined potash ores are relatively high in contrast to bedded potash ores. The K/Br ratios of veined potash ores exhibit a positive correlation with Br contents, which is opposite to that of the bedded potash ore of the MPD and potassium-salts from the evaporation of modern seawater. The contents of heavy metals in veined potash ores are much higher than those of bedded potash ores in the MPD and potash in other evaporite basins of the world. Sr and S isotopic compositions of these two types of potash ores suggest that the brines for precipitating veined potash were formed by mixing of connate waters (seawater or/and continental freshwater) and hydrothermal fluids. The geochemical and petrological characteristics of the veined potash ores indicate that the brine for forming veined potash orebodies caused by dissolution of previous bedded potash orebodies by hydrothermal fluids. The veined potash orebodies were formed through a cooling process by which sylvite precipitated first prior to halite. [ABSTRACT FROM AUTHOR]

Reconstruction of the diagenetic evolution of reservoirs is one of the most significant tasks in oil and gas exploration and development. Assessing the accurate timing of diagenetic events is critical to better understand the process of reservoir evolution, but the isotope dating of diagenetic events is technically challenging. This paper uses three case studies in the sedimentary basins in China to demonstrate the promising application of recently developed LA-(MC)-ICPMS in-situ U-Pb geochronology. Our results show that the new U-Pb dating method provides a reliable and efficient chronological approach to determine the absolute ages of diagenetic events. For example, the U-Pb age data of the Cambrian carbonate reservoir in the Tarim Basin reveals three diagenetic events at 526±14, 515±21, and 481±4.6 Ma, respectively. It is worth noting that microscopic observations are particularly important for improving the success rate of U-Pb dating. In addition, the recent progress and future prospects in the in-situ U-Pb dating method are also discussed in this study, suggesting that this method is currently hindered by the lack of international carbonate standards for data correction. [ABSTRACT FROM AUTHOR]

Isotopic analyses of human remains have the potential to alter our understanding of prehistoric lifeways and migration in Australia, but very few such analyses have been conducted in the country to date. Here, we report the first regional multiproxy isotope study of pre-contact human remains from Australia. We obtained δ13Ccollagen, δ15Ncollagen, δ18Obioapatite, δ13Cbioapatite and 87Sr/86Sr isotope values from three complex interments and two simple beach burials from the Flinders Group of Islands, Queensland. The study had two goals. One was to assess how the diets of the individuals compared to those of pre-contact populations elsewhere in the region. The other goal was to test the hypothesis that burial type was indicative of local/non-local status. We found that the individuals’ diets were diverse and included a relatively high percentage of low trophic level foods. With regard to the difference in burial practices, we found those afforded complex burials had grown up in the Flinders Group, while those given beach burials likely grew up away from the islands. These results highlight the intricacies of the lives of the Indigenous Australians who inhabited the islands and inform our understanding of their pre-contact diet and mobility. The results also suggest that multiproxy isotope studies may be able to aid with the repatriation of unprovenanced remains of Indigenous Australians. [ABSTRACT FROM AUTHOR]

Homo erectus is the founding early hominin species of Island Southeast Asia, and reached Java (Indonesia) more than 1.5 million years ago1,2. Twelve H. erectus calvaria (skull caps) and two tibiae (lower leg bones) were discovered from a bone bed located about 20 m above the Solo River at Ngandong (Central Java) between 1931 and 19333,4, and are of the youngest, most-advanced form of H. erectus5–8. Despite the importance of the Ngandong fossils, the relationship between the fossils, terrace fill and ages have been heavily debated9–14. Here, to resolve the age of the Ngandong evidence, we use Bayesian modelling of 52 radiometric age estimates to establish—to our knowledge—the first robust chronology at regional, valley and local scales. We used uranium-series dating of speleothems to constrain regional landscape evolution; luminescence, 40argon/39argon (40Ar/39Ar) and uranium-series dating to constrain the sequence of terrace evolution; and applied uranium-series and uranium series–electron-spin resonance (US–ESR) dating to non-human fossils to directly date our re-excavation of Ngandong5,15. We show that at least by 500 thousand years ago (ka) the Solo River was diverted into the Kendeng Hills, and that it formed the Solo terrace sequence between 316 and 31 ka and the Ngandong terrace between about 140 and 92 ka. Non-human fossils recovered during the re-excavation of Ngandong date to between 109 and 106 ka (uranium-series minimum)16 and 134 and 118 ka (US–ESR), with modelled ages of 117 to 108 thousand years (kyr) for the H. erectus bone bed, which accumulated during flood conditions3,17. These results negate the extreme ages that have been proposed for the site and solidify Ngandong as the last known occurrence of this long-lived species.Bayesian modelling of radiometric age estimates provides a robust chronology for Homo erectus at Ngandong (Java), confirming that this site currently represents the last known occurrence of this species. [ABSTRACT FROM AUTHOR]

Humans seem to have an adaptive predisposition for inventing, telling and consuming stories1. Prehistoric cave art provides the most direct insight that we have into the earliest storytelling2–5, in the form of narrative compositions or 'scenes'2,5 that feature clear figurative depictions of sets of figures in spatial proximity to each other, and from which one can infer actions taking place among the figures5. The Upper Palaeolithic cave art of Europe hosts the oldest previously known images of humans and animals interacting in recognizable scenes2,5, and of therianthropes6,7—abstract beings that combine qualities of both people and animals, and which arguably communicated narrative fiction of some kind (folklore, religious myths, spiritual beliefs and so on). In this record of creative expression (spanning from about 40 thousand years ago (ka) until the beginning of the Holocene epoch at around 10 ka), scenes in cave art are generally rare and chronologically late (dating to about 21–14 ka)7, and clear representations of therianthropes are uncommon6—the oldest such image is a carved figurine from Germany of a human with a feline head (dated to about 40–39 ka)8. Here we describe an elaborate rock art panel from the limestone cave of Leang Bulu' Sipong 4 (Sulawesi, Indonesia) that portrays several figures that appear to represent therianthropes hunting wild pigs and dwarf bovids; this painting has been dated to at least 43.9 ka on the basis of uranium-series analysis of overlying speleothems. This hunting scene is—to our knowledge—currently the oldest pictorial record of storytelling and the earliest figurative artwork in the world. A rock art panel from Sulawesi—dated to at least 43.9 thousand years ago—represents the oldest currently known figurative art in the world, and provides evidence of early storytelling through narrative hunting scenes. [ABSTRACT FROM AUTHOR]

The 2–7-year periodicities recorded in fossil coral records have been widely used to identify paleo-El Niño events. However, the reliability of this approach in the South China Sea (SCS) has not been assessed in detail. Therefore, this paper presents monthly resolution geochemical records covering the period 1978–2015 obtained from a Porites coral recovered from the SCS to test the reliability of this method. The results suggest that the SCS coral reliably recorded local seawater conditions and the super El Niño events that occurred over the past 3 decades, but does not appear to have been sensitive enough to record all the other El Niños. In detail, the Sr/Ca series distinctly documents only the two super El Niños of 1997–1998 and 2014–2016 as obvious low values, but does not match the Oceanic Niño Index well. The super El Niño of 1982–1983 was identified by the growth hiatus caused by the coral bleaching and subsequent death of the coral. Three distinct stepwise variations occur in the δ13C series that are coincident with the three super El Niños, which may be related to a substantial decline in endosymbiotic zooxanthellae density caused by the increase in temperature during an El Niño or the selective utilization of different zooxanthellaes that was required to survive in the extreme environment. The increase in rainfall and temperatures over the SCS during El Niños counteracts the effects on seawater δ18O (δ18Osw) and salinity; consequently, coral Δδ18O series can be used as a proxy for δ18Osw and salinity, but are not appropriate for identifying El Niño activity. The findings presented here suggest that the method to identify paleo-El Niño activity based on the 2–7-year periodicities preserved in the SCS coral records might not be reliable, because the SCS is on the edge of El Niño anomalies due to its great distance from the central equatorial Pacific and the imprints of weak and medium strength El Niño events may not be recorded by the corals there. [ABSTRACT FROM AUTHOR]

The composition of lower crust of the Tarim Craton in NW China is essential to understand the petrogenesis of the ~290-275 Ma Tarim basalts and associated intermediate-felsic rocks. However, it remains poorly constrained because extremely sparse granulite terrains or granulite xenoliths have been found in the Tarim Craton. New trace element and Sr-Nd-Pb isotopic data are reported for the Neoarchean and Neoproterozoic igneous rocks widely distributed in the northern margin of the Tarim Craton. The Neoarchean granitic gneisses show fractionated REE (rare earth element) patterns [(La/Yb) = 12-58, Yb = 10.6-36] with pronounced negative Nb-Ta and Ti anomalies. These features, together with negative εNd (−0.7 to −3.2) suggest that they were derived from melting of mafic lower crust. The Neoproterozoic biotite granodiorites are strongly depleted in HREE with (La/Yb) up to 55. They are characterized by high Sr (671-789 ppm) but very low Y (7.10-8.06 ppm) and Yb contents (0.47-0.58 ppm), showing typical features of adakitic rocks. The samples with different SiO contents display identical Sr/Sr (0.7101-0.7103), εNd (−14.1 to −15.7) and Pb isotopes (Pb/Pb = 36.94-37.07). These features together with arc-like trace element patterns suggest that they were derived from melting of thickened lower crust. In comparison, the Neoproterozoic hornblende-biotite granodiorites have similar trace element compositions except for weaker depletion in HREE and have lower Sr/Sr (0.7078) and initial Pb isotopes, and higher εNd (−12.3 to −12.7). This suggests that they were formed by melting of old lower continental crust at a shallower depth than the biotite granodiorites. These rocks were derived from the lower crust, thus providing valuable information on the nature of the lower crust beneath northern Tarim. Combined with published data, the Sr/Sr, εNd, Pb/Pb and εHf of the northern Tarim lower crust ranges from 0.7055 to 0.7103, from −12 to −17, from 16.20 to 16.65, and from −7 to −19, respectively, at ~785 Ma. These data also suggest vertical compositional heterogeneity of the northern Tarim lower crust. [ABSTRACT FROM AUTHOR]

The dispersion, stabilization and rheological properties of the slurry with various relative molecular masses of PVB were studied. The sintering properties, microstructure and dielectric properties of borosilicate glass/AlO composites were also investigated. The intensities of the typical vibrating bands decrease with the decrease of the relative molecular mass of PVB, which demonstrates that the content of butyral groups in PVB binders decreases correspondingly, leading to a rapid decrease in the viscosity of the mixed slurry. The solid content of samples increases with the decrease of the relative molecular mass of PVB, and this further leads to the increase of tape thickness, bulk density and dried-shrinkage coefficient of tapes. The bulk density, relative density, three-point strength and dielectric constant of sintered samples increase with the increase of the solid content, and the shrinkage and dielectric loss decrease. By contrast, samples for PVB-5s exhibit better properties of a bulk density of 3.10 g/cm, a relative density of 98.1%, a three-point strength of 208 MPa, a ɛ value of 8.01, a tan δ value of 7.6×10 at 10 MHz and a well matching with Ag electrodes. [ABSTRACT FROM AUTHOR]

The effects of alkali oxides (NaO and KO) addition on both the sintering behavior and dielectric properties of Ca-Al-B-Si-O glass/AlO composites were investigated by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimeter (DSC), X-ray diffractometry (XRD) and scanning electron microscopy (SEM). The results show that the increasing amount of alkali oxides in the glass causes the decrease of [SiO], which results in the decrease of the continuity of glass network, and leads to the decrease of the softening temperature T of the samples and the increasing trend of crystallization. And that deduces corresponding rise of densification, dielectric constant, dielectric loss of the low temperature co-fired ceramic (LTCC) materials and the decrease of its thermal conductivity. By contrast, the borosilicate glass/AlO composites with 1.5% (mass fraction) alkali oxides sintered at 875 °C for 30 min exhibit better properties of a bulk density of 2.79 g/cm, a porosity of 0.48%, a λ value of 2.28 W/(m·K), a ɛ value of 7.82 and a tan δ value of 9.1×10 (measured at 10 MHz). [ABSTRACT FROM AUTHOR]

Because of the complication of turbulence’s mechanism and law as well as the jet pressure in nozzle is difficult to test by experiment, five turbulent models were applied to numerically simulate the turbulent flow field in convergent-divergent nozzle. Theory analysis and experiment results of mass flow rates conclude that the RNG k-ɛ model is the most suitable model. The pressure distribution in the convergent-divergent nozzle was revealed by computational fluid dynamic (CFD) simulating on the turbulent flow field under different pressure conditions. The growing conditions of cavitation bubbles were shown; meanwhile, the phenomena in the experiment could be explained. The differential pressure between the upstream and downstream in nozzle throat section can improve the cavitating effect of cavitation water jet. [ABSTRACT FROM AUTHOR]

Reef development during past Interglacial periods, when sea level and sea surface temperatures were higher than today, provide unique insights into how reef systems may respond to projected human-induced global warming. Lord Howe Island currently represents the southernmost limit of reef development in the Pacific. Reef growth of Pleistocene age has been inferred to have occurred around the island, and this paper provides the first detailed descriptions on the character of this development. Two phases of reef growth are identified, which occurred as isolated fringing reefs along the edge of the basaltic hills of the island. Uranium-series dating indicates that the upper part of the sequence is of Last Interglacial age, however extensive calcite recrystallisation meant the lower part of the sequence does not yield reliable ages. Calcite cements suggest that several phases of recrystallisation have occurred meaning the lower part of the sequence is most likely to represent reef of Penultimate Interglacial age. Component analysis of the sedimentary matrix within the reef indicates coralline algae dominated sands which are very similar to the modern reef environment. This suggests that the environment at Lord Howe Island has remained at or close to the environmental limits for reef growth during the past few interglacials, despite lithospheric plate motion moving this island further north into reef building seas. [ABSTRACT FROM AUTHOR]

A correction to the article "An 80 kyr-long continuous speleothem record from Dim Cave, SW Turkey with paleoclimatic implications for the Eastern Mediterranean" that was published online in the September 4, 2015 issue is presented.

Speleothem-based stable isotope records are valuable in sub-humid and semi-arid settings where many other terrestrial climate proxies are fragmentary. The Eastern Mediterranean is one such region. Here we present an 80-kyr-long precisely-dated (by U-series) and high-resolution oxygen (δ18O) and carbon (δ13C) records from Dim Cave (~36°N) in SW Turkey. The glacial-interglacial δ18O variations in the Dim Cave speleothem are best explained in terms of changes in the trajectories of winter westerly air masses. These are along a northerly (European) track (isotopically less depleted) during the early last glaciation but are gradually depressed southward closer to the modern westerly track along the North African coast (more depleted) after c.50 kyr and remain in the southern track through the Last Glacial Maximum. The southward displacement of the westerly track reflects growth of the Fennoscandian ice sheet and its impact on westerly wind fields. Changes in δ13C are interpreted as reflecting soil organic matter composition and/or thickness. δ13C values are significantly more negative in interglacials reflecting active carbonic acid production in the soil and less negative in glacial times reflecting carbonate rock values. Several Heinrich events are recorded in the Dim record indicating intensification of westerly flow across this part of the EM. [ABSTRACT FROM AUTHOR]