Two-billion-year-old volcanism on the Moon from Chang'e-5 basalts.

The Moon has a magmatic and thermal history that is distinct from that of the terrestrial planets1. Radioisotope dating of lunar samples suggests that most lunar basaltic magmatism ceased by around 2.9-2.8 billion years ago (Ga)2,3, although younger basalts between 3 Ga and 1 Ga have been suggested by crater-counting chronology, which has large uncertainties owing to the lack of returned samples for calibration4,5. Here we report a precise lead-lead age of 2,030 ± 4 million years ago for basalt clasts returned by the Chang'e-5 mission, and a 238U/204Pb ratio (µ value)6 of about 680 for a source that evolved through two stages of differentiation. This is the youngest crystallization age reported so far for lunar basalts by radiometric dating, extending the duration of lunar volcanism by approximately 800-900 million years. The µ value of the Chang'e-5 basalt mantle source is within the range of low-titanium and high-titanium basalts from Apollo sites (µ value of about 300-1,000), but notably lower than those of potassium, rare-earth elements and phosphorus (KREEP) and high-aluminium basalts7 (µ value of about 2,600-3,700), indicating that the Chang'e-5 basalts were produced by melting of a KREEP-poor source. This age provides a pivotal calibration point for crater-counting chronology in the inner Solar System and provides insight on the volcanic and thermal history of the Moon.

Sediment subduction in Hadean revealed by machine learning.

Due to the scarcity of rock samples, the Hadean Era predating 4 billion years ago (Ga) poses challenges in understanding geological processes like subaerial weathering and plate tectonics that are critical for the evolution of life. The Jack Hills zircon from Western Australia, the primary Hadean samples available, offer valuable insights into magma sources and tectonic genesis through trace element signatures. However, a consensus on these signatures has not been reached. To address this, we developed a machine learning classifier capable of deciphering the geochemical fingerprints of zircon. This allowed us to identify the oldest detrital zircon originating from sedimentary-derived "S-type" granites. Our results indicate the presence of S-type granites as early as 4.24 Ga, persisting throughout the Hadean into the Archean. Examining global detrital zircon across Earth's history reveals consistent supercontinent-like cycles from the present back to the Hadean. These findings suggest that a significant amount of Hadean continental crust was exposed, weathered into sediments, and incorporated into the magma sources of Jack Hills zircon. Only the early operation of both subaerial weathering and plate subduction can account for the prevalence of S-type granites we observe. Additionally, the periodic evolution of S-type granite proportions implies that subduction-driven tectonic cycles were active during the Hadean, at least around 4.2 Ga. The evidence thus points toward an early Earth resembling the modern Earth in terms of active tectonics and habitable surface conditions. This suggests the potential for life to originate in environments like warm ponds rather than extreme hydrothermal settings.

Growth and thermal maturation of the Toba magma reservoir.

The Toba volcanic system in Indonesia has produced two of the largest eruptions (>2,000 km3 dense-rock equivalent [DRE] each) on Earth since the Quaternary. U-Pb crystallization ages of zircon span a period of ∼600 ky before each eruptive event, and in the run-up to each eruption, the mean and variance of the zircons' U content decrease. To quantify the process of accumulation of eruptible magma underneath the Toba caldera, we integrated these observations with thermal and geochemical modeling. We show that caldera-forming eruptions at Toba are the result of progressive thermal maturation of the upper crustal magma reservoir, which grows and chemically homogenizes, by sustained magma influx at average volumetric rates between 0.008 and 0.01 km3/y over the past 2.2 My. Protracted thermal pulses related to magma-recharge events prime the system for eruption without necessarily requiring an increased magma-recharge rate before the two supereruptions. If the rate of magma input was maintained since the last supereruption of Toba at 75 ka, eruptible magma is currently accumulating at a minimum rate of ∼4.2 km3 per millennium, and the current estimate of the total volume of potentially eruptible magma available today is a minimum of ∼315 km3 Our approach to evaluate magma flux and the rate of eruptible magma accumulation is applicable to other volcanic systems capable of producing supereruptions and thereby could help in assessing the potential of active volcanic systems to feed supereruptions.

Spectral Characteristics of Salinized Soils during Microbial Remediation Processes.

In this study, the spectral reflectance of saline soils, the associated soil salt content (SSC) and the concentrations of salt ions were measured and analysed by tracing the container microbial remediation experiments for saline soil (main salt is sodium chloride) of Dongying City, Shandong Province. The sensitive spectral reflectance bands of saline soils to SSC, Cl- and Na+ in the process of microbial remediation were analysed. The average-dimension reduction of these bands was conducted by using a combination of correlation coefficient and decision coefficient, and by gradually narrowing the sampling interval method. Results showed that the tendency and magnitude of the average spectral reflectance in all bands of saline soils during the total remediation processes were nearly consistent with SSC and with Cl- coocentration, respectively. The degree of salinity of the soil, including SSC and salt ion concentrations, had a significant positive correlation with the spectral reflectance of all bands, particularly in the near-infrared band. The optimal spectral bands of SSC were 1370 to 1445 nm and 1447 to 1608 nm, whereas the optimal spectral bands of Cl- and Na+ were 1336 to 1461 nm and 1471 to 1561 nm, respectively. The relationship model among SSC, soil salt ion concentrations (Cl- and Na+) and soil spectral reflectance of the corresponding optimal spectral band was established. The largest R2 of relationship model between SSC and the average reflectance of associated optimal band reached to 0.95, and RMSEC and RMSEP were 1.076 and 0.591, respectively. Significant statistical analysis of salt factors and soil reflectance for different microbial remediation processes indicated that the spectral response characteristics and sensitivity of SSC to soil reflectance, which implied the feasibility of high spectrum test on soil microbial remediation monitoring, also provided the basis for quick nondestructive monitoring soil bioremediation process by soil spectral reflectance.

Three-stage niobium mineralization at Bayan Obo, China.

The Chinese Bayan Obo deposit is a world-class rare earth element (REE) deposit with considerable niobium (Nb) and iron (Fe) resources. A complete genetic understanding on all metals is fundamental for establishing genetic models at Bayan Obo. With extensive research being focused on REE enrichment, the timing and controls of Nb enrichment remain unresolved at Bayan Obo, which is mainly due to the challenges in dating, i.e. multistage thermal events, fine-grained minerals with complex textures and the rare occurrence of uranium-enriched minerals with mature dating methods. Based on robust geological and petrographic frameworks, here we conducted ion probe uranium-lead (U-Pb) dating of ferrocolumbite to unravel the timing, hence the genesis of Nb mineralization. Three types of hydrothermal ferrocolumbites-key Nb-bearing minerals-are identified based on their textures and mineral assemblages. They yield U-Pb ages of 1312 ± 47 Ma (n = 99), 438 ± 7 Ma (n = 93), and 268 ± 5 Ma (n = 19), respectively. In line with deposit geology, we tentatively link the first, second and third stage Nb mineralization to Mesoproterozoic carbonatite magmatism, ubiquitous early Paleozoic hydrothermal activity, and Permian granitic magmatism, respectively. While quantifying the contribution of metal endowment from each stage requires further investigation, our new dates highlight that multi-stage mineralization is critical for Nb enrichment at Bayan Obo, which may also have implications for the enrichment mechanism of Nb in REE deposits in general.

Early diabetic kidney disease: Focus on the glycocalyx.

The incidence of diabetic kidney disease (DKD) is sharply increasing worldwide. Microalbuminuria is the primary clinical marker used to identify DKD, and its initiating step in diabetes is glomerular endothelial cell dysfunction, particularly glycocalyx impairment. The glycocalyx found on the surface of glomerular endothelial cells, is a dynamic hydrated layer structure composed of pro-teoglycans, glycoproteins, and some adsorbed soluble components. It reinforces the negative charge barrier, transduces the shear stress, and mediates the interaction of blood corpuscles and podocytes with endothelial cells. In the high-glucose environment of diabetes, excessive reactive oxygen species and proinflammatory cytokines can damage the endothelial glycocalyx (EG) both directly and indirectly, which induces the production of microalbuminuria. Further research is required to elucidate the role of the podocyte glycocalyx, which may, together with endothelial cells, form a line of defense against albumin filtration. Interestingly, recent research has confirmed that the negative charge barrier function of the glycocalyx found in the glomerular basement membrane and its repulsion effect on albumin is limited. Therefore, to improve the early diagnosis and treatment of DKD, the potential mechanisms of EG degradation must be analyzed and more responsive and controllable targets must be explored. The content of this review will provide insights for future research.

Low Ni and Co olivine in Chang'E-5 basalts reveals the origin of the young volcanism on the Moon.

Mare basalts returned by the Chang'E-5 (CE5) mission extend the duration of lunar volcanism almost one billion years longer than previously dated. Recent studies demonstrated that the young volcanism was related neither to radiogenic heating nor to hydrous melting. These findings beg the question of how the young lunar volcanism happened. Here we perform high-precision minor element analyses of olivine in the CE5 basalts, focusing on Ni and Co. Our results reveal that the CE5 basalt olivines have overall lower Ni and Co than those in the Apollo low-Ti basalts. The distinctive olivine chemistry with recently reported bulk-rock chemistry carries evidence for more late-stage clinopyroxene-ilmenite cumulates of the lunar magma ocean (LMO) in the CE5 mantle source. The involvement of these Fe-rich cumulates could lower the mantle melting temperature and produce low MgO magma, inhibiting Ni and Co partitioning into the magma during lunar mantle melting and forming low Ni and Co olivines for the CE5 basalts. Moreover, the CE5 olivines show a continuous decrease of Ni and Co with crystallization proceeding. Fractional crystallization modeling indicates that Co decreasing with crystallization resulted from CaO and TiO2 enrichment (with MgO and SiO2 depletion) in the CE5 primary magma. This further supports the significant contribution of late-stage LMO cumulates to the CE5 volcanic formation. We suggest that adding easily melted LMO components resulting in mantle melting point depression is a key pathway for driving prolonged lunar volcanism. This study highlights the usefulness of olivine for investigating magmatic processes on the Moon.

No evidence of supracrustal recycling in Si-O isotopes of Earth's oldest rocks 4 Ga ago.

Identifying the oldest evidence for the recycling of hydrated crust into magma on Earth is important because it is most effectively achieved by subduction. However, given the sparse geological record of early Earth, the timing of first supracrustal recycling is controversial. Silicon and oxygen isotopes have been used as indicators of crustal evolution on Archean igneous rocks and minerals to trace supracrustal recycling but with variable results. We present Si-O isotopes of Earth's oldest rocks [4.0 billion years ago (Ga)] from the Acasta Gneiss Complex, northwest Canada, obtained using multiple techniques applied to zircon, quartz, and whole rock samples. Undisturbed zircon is considered the most reliable recorder of primary Si signatures. By combining reliable Si isotope data from the Acasta samples with filtered data from Archean rocks globally, we observe that widespread evidence for a heavy Si signature is recorded since 3.8 Ga, marking the earliest record of surface silicon recycling.

Viral contamination on the surfaces of the personal protective equipment among health care professionals working in COVID-19 wards: A single-center prospective, observational study.

OBJECTIVE: To evaluate potential viral contamination on the surfaces of personal protective equipment (PPE) in COVID-19 wards. METHODS: Face shields, gloves, the chest area of PPE and shoe soles were sampled at different time points. The samples were tested for the presence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by PCR, and the cycle threshold (CT) values were recorded. RESULTS: The positive rate was 74.7% (239/320) for all PPE specimens. The CT values of the samples were ranked in the following order: face shields > chests > gloves > shoe soles (37.08±1.38, 35.48±2.02, 34.17±1.91 and 33.52±3.16, respectively; P for trend < .001). After disinfection, the CT values of shoe soles decreased compared with before disinfection (32.78±3.47 vs. 34.3±2.61, P = .037), whereas no significant effect of disinfection on the CT values of face shields, chests and gloves was observed. After disinfection, the CT values of specimens collected from shoe soles gradually increased; before disinfection, the CT values of shoe sole specimens were all less than 35. CONCLUSIONS: SARS-CoV-2 can attach to the surfaces of the PPE of healthcare professionals in COVID-19 wards, especially the shoe soles and undisinfected gloves. Shoe soles had the highest SARS-CoV-2 loads among all tested PPE items.

Simultaneous determination of 143Nd/144Nd and 147Sm/144Nd ratios and Sm-Nd contents from the same filament loaded with purified Sm-Nd aliquot from geological samples by isotope dilution thermal ionization mass spectrometry.

Isotope dilution thermal ionization mass spectrometry (ID-TIMS) is the standard technique used to achieve precise (143)Nd/(144)Nd and (147)Sm/(144)Nd isotope ratios and accurate elemental concentrations of Sm-Nd. However, in previous studies, purified Sm and Nd fractions must be individually loaded onto different filaments for their accurate determination using TIMS because of severe isobaric interferences. Thus, the classical ID-TIMS technique is time consuming and laborious. In this study, a new method is proposed, which is able to acquire both ratios of (143)Nd/(144)Nd and (147)Sm/(144)Nd and concentrations of Sm-Nd simultaneously on the same filament arrangement. The measurement time and filament consumption are reduced by 50% with the current method, and therefore, the operation cost of TIMS is significantly reduced. A mixed (152)Sm-(148)Nd spike was employed to achieve accurate results after spike subtraction and isobaric interference corrections. Results obtained from a series of standard rock samples are in good agreement with recommended values, within ±0.003% for the (143)Nd/(144)Nd ratio and ±1% for the (147)Sm/(144)Nd ratio.

Fusible mantle cumulates trigger young mare volcanism on the cooling Moon.

The Chang'E-5 (CE5) mission has demonstrated that lunar volcanism was still active until two billion years ago, much younger than the previous isotopically dated lunar basalts. How the small Moon retained enough heat to drive such late volcanism is unknown, particularly as the CE5 mantle source was anhydrous and depleted in heat-producing elements. We conduct fractional crystallization and mantle melting simulations that show that mantle melting point depression by the presence of fusible, easily melted components could trigger young volcanism. Enriched in calcium oxide and titanium dioxide compared to older Apollo magmas, the young CE5 magma was, thus, sourced from the overturn of the late-stage fusible cumulates of the lunar magma ocean. Mantle melting point depression is the first mechanism to account for young volcanism on the Moon that is consistent with the newly returned CE5 basalts.

The tempo of Ediacaran evolution.

The rise of complex macroscopic life occurred during the Ediacaran Period, an interval that witnessed large-scale disturbances to biogeochemical systems. The current Ediacaran chronostratigraphic framework is of insufficient resolution to provide robust global correlation schemes or test hypotheses for the role of biogeochemical cycling in the evolution of complex life. Here, we present new radio-isotopic dates from Ediacaran strata that directly constrain key fossil assemblages and large-magnitude carbon cycle perturbations. These new dates and integrated global correlations demonstrate that late Ediacaran strata of South China are time transgressive and that the 575- to 550-Ma interval is marked by two large negative carbon isotope excursions: the Shuram and a younger one that ended ca. 550 Ma ago. These data calibrate the tempo of Ediacaran evolution characterized by intervals of tens of millions of years of increasing ecosystem complexity, interrupted by biological turnovers that coincide with large perturbations to the carbon cycle.

The recruitment of exogenous endothelial progenitor cells in lung tumor model of nude mice.

BACKGROUND AND OBJECTIVE: Endothelial progenitor cells (EPCs) play an important role in hypoxia-triggered tumor vasculogenesis. However, the homing of exogenous EPCs in tumors is still unclear. In this study, we investigated the recruitment of exogenous EPCs in human lung adenocarcinoma model of nude mice. METHODS: EPCs labeled with green fluorescence protein (GFP) were transplanted into nude mice bearing human lung adenocarcinoma. The growth of tumor was observed. After the mice were killed, GFP-EPCs in different tissues were examined by fluorescence. The tumor tissues were stained for CD133, hypoxia-inducible factor-1alpha (HIF-1α), stromal cell-derived factor-1α (SDF-1α), and vascular endothelial growth factor receptor (KDR). Real-time polymerase chain reaction of CD133, HIF-1α, SDF-1α, and VEGF-1 were also performed. RESULTS: The growth of tumor in EPC group was significantly faster than that in saline solution group (P <0.05). Under fluorescence microscope, GFP-EPCs were strongly expressed in both tumor and bone marrow. EPCs were recruited to the tumor periphery to participate in tumor vasculogenesis. The expression of CD133, HIF-1α, and SDF-1 mRNA in tumor and bone marrow were significantly higher than that in the liver, spleen, and skin (P<0.05). CONCLUSIONS: Exogenous EPCs can be recruited to tumor and accelerate tumor growth. Except tumor, bone marrow can also recruit EPCs.

[Renal protective effects of benidipine and valsartan in primary hypertension patients with proteinuria].

OBJECTIVE: To compare the renal protective effects between calcium channel blocker benidipine and angiotensin II receptor blocker valsartan in primary hypertension patients with proteinuria. METHODS: A total of 236 patients were divided to low (< 1 g/24 h) and high (1 - 3 g/24 h) proteinuria groups and treated with benidipine (8 mg/d) or valsartan (80 mg/d) for 48 weeks. Blood pressure, glomerular filtration rate (GFR) and 24 h protein were measured at baseline, 12, 24 and 48 weeks. RESULTS: Blood pressure was significantly and equally reduced in all treated groups (all P < 0.05 vs. baseline). GFR was also significantly and equally improved in all treated groups after 24 weeks treatments (all P < 0.05 at 24 weeks and 48 weeks). Proteinuria reduction at 24 and 48 weeks was more significant in patients treated with valsartan compared to patients treated with benidipine in low proteinuria group [24 weeks: (0.27 +/- 0.07) g/24 h vs. (0.39 +/- 0.06) g/24 h, P < 0.01; 48 weeks: (0.18 +/- 0.01) g/24 h vs. (0.30 +/- 0.05) g/24 h, P < 0.01]. CONCLUSION: The renal protection efficacy of valsartan and benidipine was similar in primary hypertensive patients with proteinuria.

Impact and Correction of Analytical Positioning on Accuracy of Zircon U-Pb Dating by SIMS.

Secondary ion mass spectrometry (SIMS) is one of the most important analytical tools for geochronology, especially for zircon U-Pb dating. Due to its advantages in spatial resolution and analytical precision, SIMS is the preferred option for multi-spot analyses on single zircon grain with complex structures. However, whether or how much the relative positions of multiple analytical spots on one zircon grain affect the U-Pb age accuracy is an important issue that has been neglected by most researchers. In this study, we carried out a series of investigation on the influence of relative analytical position during zircon U-Pb age analyses, using Cameca IMS 1280-HR instrument. The results demonstrated a significant influence on the second spot, with apparent U-Pb age deviation as high as around 10% especially on the left and right side with overlap in the raster area. Nevertheless, a linear correlation between a secondary ion centering parameter (DTCA-X) and age deviation in percentage terms was found, and a calibration method was established to correct this position effect. Four zircon standards (91500, M257, TEMORA-2, and Plesovice) were measured to prove the reliability of the established procedure. The original U-Pb apparent data show inconsistent deviation on four directions relative to the datum, while the final U-Pb age results is calibrated to be consistent with their recommended values, within uncertainties of ~1%. This work calls for re-examination for the previous SIMS U-Pb dating results on core-rim dating strategy, and provides a calibration protocol to correct the relative position effect.

Effects of grape seed proanthocyanidin extracts on aortic pulse wave velocity in streptozocin induced diabetic rats.

Grape seed proanthocyanidin extracts (GSPEs) have been reported to be effective in treating arteriosclerosis, while little is known about therapeutic agents against diabetic macrovascular complications. We used streptozocin to induce diabetic rats. GSPEs (250 mg/kg of body weight) were administrated to diabetic rats for 24 weeks. Aortic blood pressure and pulse wave velocity (PWV) were determined in anesthetized rats. Serum glycated hemoglobin and advanced glycation end products (AGEs) were determined. An electronic microscope was used to observe the changes in aortic ultrastructure. Immunohistochemistry was used to evaluate the receptor of advanced glycation end product (RAGE) protein expression in aortic tissue. GSPEs significantly decreased aortic PWV, blood pressure, and aortic medial thickness (P<0.05), and inhibited the migration of vascular smooth muscle cells. GSPEs significantly reduced the AGEs (P<0.05) and the expression of RAGE in aortas of diabetic rats. GSPEs play an important role against diabetic macrovascular complications. This study may provide a new recognition of natural medicine for the treatment of diabetic macrovascular complications.

[The progress in retrieving land surface temperature based on thermal infrared and microwave remote sensing technologies].

Land surface temperature (LST) is an important parameter in the study on the exchange of substance and energy between land surface and air for the land surface physics process at regional and global scales. Many applications of satellites remotely sensed data must provide exact and quantificational LST, such as drought, high temperature, forest fire, earthquake, hydrology and the vegetation monitor, and the models of global circulation and regional climate also need LST as input parameter. Therefore, the retrieval of LST using remote sensing technology becomes one of the key tasks in quantificational remote sensing study. Normally, in the spectrum bands, the thermal infrared (TIR, 3-15 microm) and microwave bands (1 mm-1 m) are important for retrieval of the LST. In the present paper, firstly, several methods for estimating the LST on the basis of thermal infrared (TIR) remote sensing were synthetically reviewed, i. e., the LST measured with an ground-base infrared thermometer, the LST retrieval from mono-window algorithm (MWA), single-channel algorithm (SCA), split-window techniques (SWT) and multi-channels algorithm(MCA), single-channel & multi-angle algorithm and multi-channels algorithm & multi-angle algorithm, and retrieval method of land surface component temperature using thermal infrared remotely sensed satellite observation. Secondly, the study status of land surface emissivity (epsilon) was presented. Thirdly, in order to retrieve LST for all weather conditions, microwave remotely sensed data, instead of thermal infrared data, have been developed recently, and the LST retrieval method from passive microwave remotely sensed data was also introduced. Finally, the main merits and shortcomings of different kinds of LST retrieval methods were discussed, respectively.

Back-regulation of six oxidative stress proteins with grape seed proanthocyanidin extracts in rat diabetic nephropathy.

Diabetic nephropathy (DN) is a major cause of morbidity and mortality in diabetic patients. To prevent the development of this disease and to improve advanced kidney injury, effective therapies directed toward the key molecular target are required. Grape seed proanthocyanidin extracts (GSPE) have been reported to be effective in treating DN, while little is known about the functional protein changes. In this study, we used streptozotocin (STZ) to induce diabetic rats. GSPE (250 mg/kg body weight/day) were administrated to diabetic rats for 24 weeks. Serum glucose, glycated hemoglobin, and advanced glycation end products were determined. Consequently, 2-D difference gel electrophoresis and mass spectrometry were used to investigate kidney protein profiles among the control, untreated and GSPE treated diabetic rats. Twenty-five proteins were found either up-regulated or down-regulated in the kidneys of untreated diabetic rats. Only nine proteins in the kidneys of diabetic rats were found to be back-regulated to normal levels after GSPE therapy. These back-regulated proteins are involved in oxidative stress, glycosylation damage, and amino acids metabolism. Our findings might help to better understanding of the mechanism of DN, and provide novel targets for estimating the effects of GSPE therapy.