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Treatment of patients with recurrence of in-stent restenosis (ISR) remains particularly challenging, with data and guideline recommendations for repeat percutaneous coronary intervention being scant. The aim of this study was to investigate the long-term incidence of recurrent revascularization events after percutaneous treatment of drug-eluting stent (DES) ISR. In this post hoc analysis, 402 patients (500 lesions) assigned to plain balloon (PB), drug-coated balloon (DCB), or DES treatment in the randomized ISAR-DESIRE 3 (Efficacy Study of Paclitaxel-Eluting Balloon, -Stent vs. Plain Angioplasty for Drug-Eluting Stent Restenosis) trial were followed up over a median of 10.3 years. The primary endpoint was total repeat target lesion revascularization (R-TLR) including all, first and recurrent, events. At the end of follow-up, first R-TLR was required in 204 lesions, 82 in the PB group, 70 in the DCB group, and 52 in the DES group. The total number of R-TLRs was 373: 162 in the PB group, 124 in the DCB group, and 87 in the DES group. During the first year of follow-up, the risk for total R-TLR was reduced by DCB (HR: 0.36; 95% CI: 0.24-0.54) and DES (HR: 0.23; 95% CI: 0.14-0.38) treatment compared with PB treatment. After 1 year, the risk for total R-TLR was nonsignificantly reduced by DCB treatment (HR: 0.77; 95% CI: 0.51-1.16) and significantly reduced by DES treatment (HR: 0.61; 95% CI: 0.39-0.95) compared with PB treatment. Risk in the DCB and DES groups was similar during (HR: 1.54; 95% CI: 0.89-2.69) and after (HR: 1.26; 95% CI: 0.82-1.92) 1 year. The total number of R-TLRs over 10 years after treatment of patients with DES ISR was high. DCBs and particularly DES were able to reduce the need for both first and recurrent revascularization compared with PB treatment. [Display omitted] [ABSTRACT FROM AUTHOR]

Innovatively regulating the crystalline-amorphous (c-a) interface of electrode materials is critical for enhancing supercapacitor and electrochemical water splitting performance. In this research, an oxygen defect-rich Fe 3 O 4 @Fe electrode material with a unique and tunable c-a interface was synthesized using prussian blue (PB) as a template. The resulting interface facilitates electron transport and ion diffusion, increases the charge storage active sites, and enhances energy storage capacity. Density functional theory (DFT) simulations demonstrated that oxygen defects can effectively enhance ionic conductivity and facilitate electrochemical water splitting. The optimal Fe 3 O 4 @Fe electrode exhibits remarkable specific capacitance (1526.766 mF cm−2 at 1 mA cm−2) and exceptional oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) performance, with overpotential values of 231 and 359 mV at 10 mA cm−2, respectively. Furthermore, as an overall water splitting electrocatalyst, the optimal Fe 3 O 4 @Fe can reach 10 mA cm−2 at a battery voltage of 1.645 V, demonstrating its tremendous potential as a highly efficient electrocatalyst. The oxygen defect-rich Fe 3 O 4 @Fe electrode materials with unique c-a interface are a kind of highly efficient multifunctional electrode material for supercapacitors and overall water splitting. [Display omitted] • The tunable c-a interface enhances electron transport, ion diffusion, and energy storage capability. • Introduction of oxygen vacancies improves electron transfer kinetics and electrochemically active area. • The unique synergistic interaction between the c-a interface and oxygen vacancies enhances rate performance. [ABSTRACT FROM AUTHOR]

Reconstructing spatiotemporal trends in Pb pollution history is important for understanding global Pb cycling, controlling Pb pollution, and allowing assessment of the extent and timing of human impacts on environments. In this study, the high-resolution heavy-metals (Pb, Zn, Cd, Cu, Co, and Ti) pollution history over the past millennium was reconstructed based on sedimentary records from Lake Chenghai in Southwestern China, and the possible origins of Pb and its relationship with global Pb records were revealed. The marked high Pb concentrations occurred during the Medieval period (1200s–1400s), and enrichment factor analysis suggested that the high pollution degrees during the Medieval period were derived primarily from the anthropogenic sources of mining activity. Furthermore, our compilation records worldwide showed that Pb pollution level in most areas of China during the Medieval period is the same as or even higher than present, while in the other regions such as America and Europe, modern-day Pb pollution level is significantly higher than that in the Medieval period. In the past two centuries, Pb concentration rapidly increased again since the 1980s in China, coinciding with China's reform and opening up that spawned social economic transformation and rapid industrial economic growth, while in America and Europe, it rapidly increased in the 1950s and then declined in the 1980s, coinciding with the impacts of industrial revolution on developed regions. Those records imply Pb could be regards as the regional human activity intensity index during the Anthropocene. This study could provide insight into the onset timing of anthropogenic impacts in different areas and also provide scientific supports for Pb pollution control. [ABSTRACT FROM AUTHOR]

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The neutron multiplier lead (Pb) containing Li 2 TiO 3 -0.5Li 4 SiO 4 –Pb was prepared, which aimed at the improvement of the tritium release performance of the lithium ceramic without an increase in lithium density. Li 2 TiO 3 -0.5Li 4 SiO 4 –Pb and that without Pb were irradiated at Kyoto University Research Reactor (KUR) with the thermal neutron flux of 5.5 × 1012 n s−1 cm−2 and the fast neutron flux of 1.2 × 1012 n s−1 cm−2. Fast neutrons can trigger the Pb (n , 2 n) reaction. The tritium release experiments were conducted using the tritium thermal desorption spectroscopy (tritium-TDS) system. Compared with Li 2 TiO 3 -0.5Li 4 SiO 4 , the tritium release rate at the lower temperature range was higher than that for Li 2 TiO 3 -0.5Li 4 SiO 4 –Pb. The tritium-TDS spectrum was also shifted to the lower temperature side. The isothermal heating experimental results confirmed that tritium in the form of gas species (HT) was controlled by the diffusion process, while the trapping and de-trapping process contributed to the total tritium release. Further, 3 keV D 2 + implantation with the fluence of 2.0 × 1022 D m−2 and subsequent TDS measurements were performed. It was shown that the D 2 release at the lower temperature side was increased for Li 2 TiO 3 -0.5Li 4 SiO 4 –Pb. Meanwhile, HD and HDO release at higher temperature side was significantly decreased. [ABSTRACT FROM AUTHOR]

Isothermal kinetic methods were used to investigate reduction process in the Zn and Pb during the vacuum carbothermal reduction of electric arc furnace dust (EAFD). During the experiments, the volatilization ratios of Zn and Pb in EAFD increased with the increase of temperature and holding time, which was 96.29 % and 83.91 % for Zn and Pb respectively at a temperature of 1000 °C and holding time of 60 min. The main phase changes of Zn and Pb in the reduction process were ZnFe 2 O 4 → ZnO → Zn and PbSO 4 → PbO → Pb, and the generated Zn and Pb gases escaped and were collected via condensation. In the kinetic study, the volatilization of Zn was controlled by three-dimensional diffusion (Jander) with an apparent activation energy of 19.97 kJ/mol, whereas the volatilization of Pb was controlled by the interfacial chemical reaction with an apparent activation energy of 85.68 kJ/mol. The results show that higher purity of valuable metals Zn and Pb could be obtained, laying a theoretical foundation for the treatment of EAFD pollution. [ABSTRACT FROM AUTHOR]

• The effect of Fe 2 O 3 on the leaching behavior of Pb in fly ash was investigated. • The mechanism of Pb leaching behavior was revealed based on phase transformation. • The PbFe 12 O 19 effectively inhibit the leaching of Pb in thermal treated fly ash. This study investigated the leaching behavior of Pb in hazardous waste incineration fly ash (HWIFA) after adding Fe 2 O 3 thermal treatment and revealed the leaching mechanism of Pb from the perspective of phase transformation. The static leaching results showed that at 600 °C-1300 °C, with the addition of Fe 2 O 3 increased, the Pb leaching toxicity continued to decrease. The dynamic results indicated that as the thermal treatment temperature was higher than 1100 °C, the addition of Fe 2 O 3 can effectively inhibit the dynamic leaching of Pb in HWIFA. Meanwhile, the inhibition effect was not very closely related to the amount of Fe 2 O 3. The addition of Fe 2 O 3 can react with PbO to form PbFe 12 O 19 , which has a better stability. The appearance of PbFe 12 O 19 was the main reason for adding Fe 2 O 3 to enhanced the immobilization of Pb. However, the amount of Fe 2 O 3 should be carefully controlled to avoid an excessive reducible fraction of Pb in the thermal treated HWIFA, which will affect the long-term stability of Pb. [ABSTRACT FROM AUTHOR]

• Lead increased levels of osmoprotectants and phenol compounds in the metallicolous Matthiola flavida. • Reduced root-to-shoot translocation and enhanced Pb accumulation in the root, under drought stress, is responsible for reduced toxic effects of Pb in the shoot of the metallicolous species. • Lead stimulates drought resistance in the metallicolous species by the accumulation of reducing sugars, phenolic compounds and antioxidant enzymes. Plants growing on quarry tailings at the Irankouh Pb/Zn mine encounter both drought stress and high levels of Pb. To better understand the role of drought and Pb in plant adaptation to Pb/Zn quarry tailings, we compared effects of drought stress (simulated by polyethylene glycol - PEG) and Pb, individually and in concert, to determine how these stressors affected two plant species: the metallicolous species Matthiola flavida (M) and the non-metallicolous congener, M. incana (NM). Plants were exposed to Pb (Pb(NO 3) 2) and three levels of PEG-6000 (0, -0.25, and -0.75 MPa) in a complete factorial design. Pb had non-significant effects on growth and oxidative stress but enhanced levels of osmoprotectants and phenol compounds in the M species M. flavida , whereas in M. incana the effect of Pb was non-significant on the same variables (except for anthocyanins and the osmoprotectants, proline and glycine betaine). Compared to M. incana , the M species M. flavida was tolerant of Pb, showing strongly reduced root-to-shoot translocation and enhanced Pb accumulation in the root (especially when under drought stress), which reduced toxic effects of Pb in the shoot. Tolerance of Pb by the M species M. flavida was aided by the accumulation of reducing sugars and phenolic compounds, as well as by greater catalase activity. [ABSTRACT FROM AUTHOR]

In this study, the Pb-resistant Ensifer adhaerens strain S24, which contains quorum sensing (QS) systems responsible for N-acyl homoserine lactone (AHL) production, was investigated for QS system-mediated Pb stabilization and the underlying mechanisms. Whole-genome sequence analysis revealed the QS SinI/R and TraI/R systems in strain S24. Subsequently, strains S24 and the S24∆ sinI/R , S24∆ traI/R , S24∆ traI/R/sinR , and S24∆ sinI/R - traI/R/sinR mutants were constructed and compared for QS SinI/SinR-TraI/TraR system-mediated Pb stabilization in the solution and the mechanisms involved. After 5 days of incubation, strain S24 significantly decreased the Pb concentration in the Pb-contaminated solution compared with the mutants. The S24∆ sinI/R - traI/R/sinR mutant exhibited reduced Pb stabilization and AHL activity than the other mutants. The S24∆ sinI/R - traI/R/sinR mutant had significantly greater Pb concentrations in the solution and lower cell surface-adsorbed and extracellular precipitated Pb (PbS) contents as well as lower expression of H 2 S-producing genes of metC and sseA than did strain S24. Furthermore, the S24∆ sinI/R - traI/R/sinR mutant displayed reduced interactions between the hydroxyl, amino, carboxyl, and ether groups and Pb, compared with strain S24. These findings implied the vital role of the SinI/SinR-TraI/TraR systems in strain S24 for Pb stabilization through enhanced cell surface adsorption and extracellular precipitation in Pb-polluted aquatic environments. [Display omitted] • QS SinI/R-TraI/R systems were identified in Pb-immobilizing Ensifer adhaerens S24. • QS systems-assisted Pb immobilization by S24 was found in the Pb-containing solution. • QS systems in S24 enhanced cell wall-adsorption and extracellular precipitate of Pb. • QS systems affected the interactions between cell surface functional groups and Pb. • QS systems enhanced the expression of H 2 S-producing genes of sseA and metB in S24. [ABSTRACT FROM AUTHOR]

High-ash coal slime-based silica fertilizer (CSF) has the potential to provide mineral nutrients and passivate lead (Pb) in the soil to ensure the sustainable development of the coal industry and agriculture. This study investigated the performance and passivation mechanism of CSF, which contains potassium tobermorite and potassium silicate as the main components for soil improvement. Leaching experiments showed that low-crystalline muscovite was the only crystalline phase for CSF etching and that the silicon (Si), calcium (Ca), and potassium (K) in CSF had significant citric solubility. Soil cultivation and planting trials confirmed the ability of CSF to neutralize soil acidity, increase available soil Si and K, improve exchangeable Ca content, reduce the bioefficacy of Pb (exchangeable Pb by 19–75 % and carbonate-bound Pb by 6–18 %), and increase residual state Pb content. Compared to untreated Pb-contaminated soil, the 0.4 % CSF treatment reduced Pb in Chinese cabbage (Brassica rapa) by 25 % and increased plant biomass, Ca, and K by 37 %, 36 %, and 4 %, respectively. At the same time, soil pH increased by 0.58, and residual state Pb increased by 5 %. In CSF-treated soils, lead silicate is the dominant form of Pb present in the residual state. First-principle calculations showed that Pb 3 Si 2 O 7 (cohesion energy −1.98 eV) formed by the passivation of Pb by CSF had greater stability in the soil compared to lead carbonate (PbCO 3) (cohesion energy −1.38 eV) and lead sulfate (PbSO 4) (cohesion energy −1.41 eV). This work shows the promising application of coal slime mineral fertilizers prepared using hydrothermal methods for soil improvement. [Display omitted] • High-ash coal slime-based silica fertilizer (CSF) was used to remediate soil. • CSF contains effective Si, Ca, and K that remain active for a long time. • CSF reduces the mobility and availability of Pb by increasing Pb residual content. • CSF effectively inhibits the uptake of Pb by plants. • xPbO·ySiO 2 is more stable and has a greater cohesive energy than PbSO 4 and PbCO 3. [ABSTRACT FROM AUTHOR]

A critical consideration in the application of phytoremediation to remediate sludge soil contaminated with heavy metals is the potential for leaching risks that prevail prior to the efficient uptake of these metals by plants. The most cost-effective method is to use heavy metal stabilizers with selective adsorption. A novel amide-based COF material (COF-TH) has been synthesized as a heavy metal stabilizer for Pb. COF-TH exhibits significant selectivity for Pb in five-metal-mixed solutions, with a distribution coefficient K D as high as 3279 mL·g–1, which was more than 7.3 times that of other heavy metals. The maximum adsorption capacity of COF-TH for Pb was 189 mg·g–1. The adsorption fitted Langmuir model and intra-particle diffusion model, and satisfied pseudo-second-order kinetic model. The excellent selectivity and adsorption performance originate from the complexation between abundant amide groups and Pb ions. Pot experiments and leaching assays confirm that COF-TH decreased Pb leachate concentrations by 77.8 % without significantly decreasing total phytoextracted amounts of other heavy metals, due to the high selectivity of COF-TH to Pb. Additionally, its positive impact on plant growth and microbial diversity makes it a promising soil remediation agent. This investigation offers a novel approach to mitigate the leaching risk of a specific heavy metal Pb during sludge land application by integrating soil phytoremediation with stabilization techniques. [Display omitted] • A novel amide-based COF material (COF-TH) is synthesized by solvent method. • COF-TH has a good selective adsorption for Pb due to its rich amide groups. • COF-TH significantly reduces the leaching risk of Pb in polluted soil. • COF-TH does not affect soil microbial diversity and promotes the plant growth. • COF-TH does not mitigate the phytoextraction of other non-target heavy metals. [ABSTRACT FROM AUTHOR]

Based on the principle of electro-Fenton (EF) reaction, this investigation was experimented to treat copper (Cu) and lead (Pb), which are lower mobile in dredged sediment in a self-made EF reactor, and simultaneously dewater it. The results of the study showed that when Fe2+ concentration was 1 mM, the initial current density was 10.4 mA/cm2, and the initial pH was neutral, after 24 h, the conversion of the stable form to the activated state of Cu and Pb were 24.77 % and 68.42 %, respectively. Further, the water content of the dredged sediment was significantly reduced from the initial 58–26 % after the EF. The mechanism experiment confirmed that ·OH and SO 4 ·- were the main factors for converting Cu and Pb forms, destroying the EPS structure in the dredged sediment and decomposing its main components, improving the dewatering property of the dredged sediment. In addition, EF treatment did not decrease microbial diversity in dredged sediments, and Flavobacterium and Bacillus , which are beneficial for agricultural production, became featured taxa after EF. This study provided a new perspective that transforms Cu and Pb into a more easily removable form with simultaneous efficient dewatering, which is more conducive to subsequent conventional treatment of the dredged sediment. • Using a novel EF reactor to treat HMs in dredged sediment and simultaneous dewatering. • Cu and Pb from oxidizable and residual states to available fraction after EF. • OH and SO 4 ·− were responsible for the transformation of Cu and Pb forms. • Reduction in water content of dredged sediment from 58.4 % to 26.3 % after EF. • Firmicutes and Actinobacteria were feature taxa after EF. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mass residual rate declined fastest at 1200–1273 °C. • Volume residual rate declined fastest at 1100–1200 °C. • Leaching rate of heavy metal Pb was the highest at ash fluid temperature (1273 °C) • The encapsulation effect of Pb was weakened with the increased Pb oxides at 1273 °C. • The optimum temperature for thermal treatment of fly ash was suggested at 1200 °C. The fly ash generated by municipal solid waste (MSW) incineration contains heavy metals, which pose a significant environmental threat. Thermal treatment emerges as a potential technique for reducing and detoxifying MSW incineration fly ash, but the optimal thermal treatment temperature remains unclear. This study explores the thermal stability of MSW incineration fly ash under various thermal treatment temperatures (1000 °C − 1500 °C). Additionally, the solidification and leaching behaviors of heavy metal Pb were investigated. The results revealed distinctive trends: the mass residual rate showed the fastest decline between 1200 °C and 1273 °C, while the volume residual rate showed the fastest decline between 1100 °C and 1200 °C. The solidification rate of heavy metal Pb decreased as the treatment temperature increased. With the decrease of specific surface area, the leaching rate of heavy metal Pb exhibited a gradual decline, but it sharply surged at the fluid temperature. This was because the encapsulation effect of Pb by calcium silicate iron manganese complex was weakened and an increase in kinds of Pb oxides(Pb 2 O 3 , Pb 3 O 4) that can react with glacial acetic acid in the leachate. Thus, it was not advisable to treat the MSW incineration fly ash around the fluid temperature. The optimal thermal treatment temperature was suggested to be 1200 °C, as it achieves goals such as volume reduction, detoxification and low energy consumption. These provide useful theoretical guidelines for the thermal treatment of MSW incineration fly ash. [ABSTRACT FROM AUTHOR]

Heavy metal pollution in water can cause severe environmental problems, harm the ecosystem, and ultimately threaten human health. The traditional methods used to remove heavy metals from water are expensive, inefficient, and can cause secondary pollution. However, microalgae have potential applications in the removal of toxic heavy metal pollutants from water. In this study, six green algae were screened in terms of their ability to adsorb cadmium (Cd) and lead (Pb) from a liquid medium. Ion content analyses confirmed that Scenedesmus acuminatus had the strongest Cd- and Pb-absorption ability. S. acuminatus was subjected to Cd and Pb treatments, and then transcriptome sequencing analysis was conducted. The results of Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses indicated that the "proteasome" pathway was enriched with differentially expressed genes (DEGs) under Cd treatment, and the "photosynthesis" pathway was enriched with DEGs under Pb treatment. These results imply that the proteasome pathway maintained protein homeostasis and cellular activity by degrading damaged proteins under Cd toxicity, and that photosynthesis was affected by Pb toxicity in S. acuminatus. In conclusion, S. acuminatus showed a strong ability to accumulate Cd/Pb and might alleviate heavy metal toxicity and reduce heavy metal efflux using the ubiquitin-proteasome system. The results of this study identify a novel microalgal strain with potential applications in phytoextraction and phytoremediation, and provide information about the molecular mechanisms of Cd/Pb accumulation in this alga. These data provide a theoretical basis for reducing Cd/Pb toxicity and will be useful for devising strategies to protect aquatic animals and plants. [Display omitted] • Scenedesmus acuminatus had stronger Cd- and Pb-absorption ability. • The "proteasome" pathway was involved with the Cd detoxification in S. acuminatus. • Gene encoding proteasome subunits had up-regulated expression under Cd/Pb treatments. • S. acuminatus may be identified as a novel phycoremediator for protecting aquatic organisms. [ABSTRACT FROM AUTHOR]

As a ubiquitous toxic heavy metal, lead (Pb) exposure is known to be implicated in the onset and development of neurodegenerative diseases which may cause more serious health hazards with age and the accumulation of Pb in the body. Autophagy is the main degradation route for abnormal aggregated proteins and damaged cell organelles. Here, we aimed to study the effects of adolescent Pb exposure on autophagy at different life nodes. In this study, we developed a time-series model of Pb exposure in mice and randomly divided 4-week-old male C57BL/6 mice into six groups (4 C, 13 C, 16 C, 4Pb, 13Pb and 16Pb). Mice in Pb groups was consumed deionized water containing 0.2 % Pb(Ac) 2 for 3 months and then reared to anticipated life nodes, while the control group consumed deionized water. Western blot and Real-time qPCR were used to assess the effects of developmental Pb exposure on individual components of the autophagy machinery and modulation of microtubule-associated protein 1 light chain 3 (LC3) at each age stage. Our results showed that Pb exposure during adolescence reduced the p-mTOR/mTOR ratios with enhanced expression of Beclin-1, Atg12 and Atg7in both the hippocampus (HPC) and prefrontal cortex (PFC) of senescent mice while upregulation of LC3II/LC3I ratios and p62 suggested that autophagy mediates degradation was interrupted. Overall, we confirm that Pb exposure during adolescence promotes autophagic processes in the aged mice brain and that autophagic degradation is hindered, ultimately leading to a failure of autophagic degradation. • Prepubertal lead (Pb) exposure lead to failed autophagy in the aging mice. • Age-varying profiles of autophagic processes were manipulate by Pb exposure. • Pb exposure decreased the p-mTOR/mTOR ratio and upregulated the LC3II/LC3I ratio. [ABSTRACT FROM AUTHOR]

To investigate the mechanism of Silent information regulator 1 (SIRT1) regulation of DNA methylation and thus the expression of synaptic plasticity-related genes induced by lead (Pb) exposure, the early-life Sprague-Dawley rats and PC12 cells were used to establish Pb exposure models and treated with SIRT1 agonists (resveratrol and SRT1720). In vivo results demonstrated that Pb exposure increased the expression of DNMTs, MeCP2, PP1 and cleaved caspase3, decreased the expression of SIRT1, BDNF and RELIN and altered DNA methylation levels of synaptic plasticity genes. Moreover, we observed marked pathological damage in the hippocampal CA1 region of the 0.2 % Pb-exposure group. After treatment with resveratrol, the effects of Pb exposure on the expression of the above molecules and pathological features were significantly ameliorated in the hippocampus of rats. In vitro results showed that after the treatment with SRT1720, the expression of SIRT1 was activated and thus reversed the effect on DNMTs, MeCP2, apoptosis and synaptic plasticity-related genes and their DNA methylation levels induced by Pb exposure. In conclusion, we validated the important protective role of SIRT1 in neurotoxicity induced by Pb exposure through in vivo and in vitro experiments, providing potential therapeutic targets for the treatment and prevention of brain damage. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • The hardness of hydroxyl group on the mineral surface affects the interaction between metal ions and mineral surface. • The hydroxyl groups on the cassiterite surface are less hard-base, while on the quartz surface are high hard-base. • The oxygen on the quartz surface has stronger localization, and it has no electron migration ability. • The oxygen on the cassiterite surface has stronger delocalization and stronger electron migration ability. • Pb2+ can more strongly interplay with cassiterite than quartz resulting in selective flotation of cassiterite from quartz. Current research has trouble explaining the selective flotation mechanism realized by metal ions, which hinders the advancement of effective flotation techniques. In this work, the selective activation flotation of cassiterite from quartz with Pb2+ is taken as an example to illustrate the pivotal roles of surface hydroxyls in selective flotation. Accordingly, flotation, adsorption amount, and X-ray photoelectron spectroscopy (XPS) measurements and systematic first-principles calculations have been used to investigate the roles of hydroxyl groups on the selective adsorption of Pb2+. The obtained flotation, adsorption amount, and XPS test results consistently show that the Pb2+ can more strongly interplay with cassiterite than quartz resulting in selective flotation of cassiterite from quartz. The electron localization functional results illustrate that the electron localization of oxygen of Si-O bonds is stronger than the Sn-O bond resulting in the weaker electron migration ability (high hardness) of oxygen atoms of quartz than oxygen atoms of cassiterite. This makes the cassiterite surface hydroxyl groups less hard than quartz. Further crystal orbital Hamilton population and partial density of states show that the Pb2+ interacts with the oxygen atoms on cassiterite forming chemical bonds before and after the adsorption of benzohydroxamic acid (BHA). On the other hand, the interaction of Pb2+ with quartz is physical in the presence of BHA. The strong adsorption of Pb2+ on cassiterite makes it easier for BHA adsorption which accounts for the selective flotation of cassiterite from quartz. This work sheds new light on establishing a consistent and dependable theory that the hardness of surface hydroxyls is the original factor affecting the selective adsorption of metal ions on oxide mineral surfaces. [ABSTRACT FROM AUTHOR]

Lead (Pb) is a heavy metal that has been recognized as a neurotoxin, meaning it can cause harmful effects on the nervous system. However, the neurotoxicology of Pb to birds still needs further study. In this study, we examined the neurotoxic effects of Pb exposure on avian cerebellum by using an animal model-Japanese quail (Coturnix japonica). The one-week old male chicks were exposed to 50, 200 and 500 mg/kg Pb of environmental relevance in the feed for five weeks. The results showed Pb caused cerebellar microstructural damages charactered by deformation of neuroglia cells, granule cells and Purkinje cells with Nissl body changes. Moreover, cerebellar neurotransmission was disturbed by Pb with increasing acetylcholine (ACh) and decreasing acetylcholinesterase (AChE), dopamine (DA), γ-Aminobutyric Acid (GABA) and Na+/K+ ATPase. Meanwhile, cerebellar oxidative stress was caused by Pb exposure represented by increasing reactive oxygen species (ROS) and malondialdehyde (MDA) as well as decreasing catalase (CAT), glutathione peroxidase (GPX), glutathione (GSH) and superoxide dismutase (SOD). Moreover, RNA-Seq analysis showed that molecular signaling pathways in the cerebellum were disrupted by Pb exposure. In particular, the disruption of nuclear factor erythroid-2-related factor 2 (Nfr2)/kelch-like ECH-associated protein 1 (Keap1) pathway and glutathione metabolism pathway indicated increasing cell apoptosis and functional disorder in the cerebellum. The present study revealed that Pb induced cerebellar toxicology through structural injury, oxidative stress, neurotransmission interference and abnormal apoptosis. [Display omitted] • Pb exposure induced microstructural injury in the cerebellum of Japanese quails. • Pb exposure interfered with cerebellar neurotransmission. • Pb caused neurotoxicology through oxidative stress to the cerebellum. • Pb led to cerebellar apoptosis via Nrf2-regulated glutathione metabolism disruption. [ABSTRACT FROM AUTHOR]

Rapid global industrialization and an increase in population have enhanced the risk of heavy metals accumulation in plant bodies to disrupt the morphological, biochemical, and physiological processes of plants. To cope with this situation, reduced graphene oxide (rGO) NPs were used first time to mitigate abiotic stresses caused in plant. In this study, rGO NPs were synthesized and reduced with Tecoma stans plant leave extract through modified Hummer's methods. The well prepared rGO NPs were characterized by ultra-violet visible spectroscopy (UV–Vis), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Zeta potential, and scanning electron microscopy (SEM). However, pot experiment was conducted with four different concentrations (15, 30, 60, 120 mg/L) of rGO NPs and three different concentrations (300, 500,700 mg/L) of lead (Pb) stress were applied. To observe the mitigative effects of rGO NPs, 30 mg/L of rGO NPs and 700 mg/L of Pb were used in combination. Changes in morphological and biochemical characteristics of wheat plants were observed for both Pb stress and rGO NPs treatments. Pb was found to inhibit the morphological and biochemical characteristics of plants. rGO NPs alone as well as in combination with Pb was found to increase the chlorophyll content of wheat plants. Under Pb stress conditions and rGO NPs treatments, antioxidant enzyme activities like ascorbate peroxidases (APX), superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) were observed. Current findings revealed that greenly reduced graphene oxide NPs can effectively promote growth in wheat plants under Pb stress by elevating chlorophyll content of leaves, reducing the Pb uptake, and suppressing ROS produced due to Pb toxicity. [Display omitted] • Reduced graphene oxide (rGO) NPs were synthetized using Tecoma stans plant extract. • RGO) NPs were characterized by Uv-spectroscopy, FTIR, XRD, Zeta potential, SEM. • Morphological and biochemical characteristics of wheat plants were detected in Pb stress. • Antioxidant enzymes APX, SOD, POD and CAT work better in rGO NPs exposure. • RGO NPs reduce the ROX production while increase chlorophyll content in Pb stress condition of wheat plants. [ABSTRACT FROM AUTHOR]

In this study, the optimal geopolymers (OGP) with excellent compressive strength and immobilization ratio are prepared by steel slag (SS), fly ash (FA), and desulfurized gypsum (DG) to immobilize Pb and Cd in the sediment. D-optimal mixing design model and Design-Expert software were used to optimized the preparation of OPG. XRD, SEM/EDS, XPS and CT were used to reveal the immobilization mechanism. Results indicated that the optimal mass ratio of SS、FA and DG is 0.604, 0.296 and 0. 100. The compressive strength of the OGP after curing 3d and 7d was 3.45 MPa and 4.90 MPa, respectively. And the immobilization rates of Pb and Cd were 99.65 % and 37.80 %, respectively. The main phase of OGP was amorphous aluminosilicate, mullite, calcium sulfate, hematite, calcium silicate hydrates and srebrodlskite. Among them, the amorphous aluminosilicate played a key role in the immobilization of Pb and Cd. The specific immobilization mechanism of Pb and Cd was concluded: (1) Cd was immobilized in OGP by ion exchange, precipitation and complexation reaction, while (2) Pb was controlled by lattice immobilization and complexation reaction. (3) the new crystalline phase containing Pb and Cd was existed by the form of amorphous phase in OGP. • A novel geopolymer with excellent compressive strength and Pb/Cd immobilization efficiency is developed. • Cd is immobilized in OGP by ion exchange, precipitation and complexation reaction. • Pb is immobilized in OGP by lattice immobilization and complexation reaction. [ABSTRACT FROM AUTHOR]

Agricultural soil pollution has attracted the attention of scientists and agricultural managers because of its importance to food security worldwide. In Syria, limited studies have been conducted to determine heavy metals (HMs) concentrations in arable lands. The objective of this study was to investigate the concentration of HMs in the southern part of Syria, and to identify the potential sources HMs. To achieve the study goals, 38 soil samples (0–25 cm) were collected and analysed for physical and chemical soil properties, while the DTPA (Diethylenetriamine pentaacetate) method was to extract HMs from soil. The results of this study showed that the average concentration of HMs in the study area are 2.00; 12.70; 8.56; 4.37; 0.12; and 0.12 ppm for Cu; Fe; Mn; Zn; Cd; and Pb, respectively. A multivariate statistical analysis showed that Cu, Fe, and Mn originated from parent material (natural resources), while Zn and Cd were related to agricultural activities (anthropogenic one) and Pb was relatively related to industrial activities. Interestingly, the spatial distribution indicates that Cu, Fe, and Mn distributed in the southern and eastern part of the study area, while Pb and Zn were dominant in the western and northern part. In addition, Cd was observed in the central part of the study area. We conclude that human activities are the main contributor of HMs accumulation in soil. The distribution of these HMs could affect the safety of agricultural product in the future. [ABSTRACT FROM AUTHOR]

Kaempferol (Kam) is a flavonoid antioxidant found in fruits and vegetables, which was discovered as neuroprotective antioxidants. Lead (Pb), an environmental pollution, could induce learning and memory deficits. Nevertheless, little is known about the mechanisms underlying Kam actions in Pb-induced learning and memory deficits. In this study, we investigated the effects of Kam on Pb-induced cognitive deficits. Pb-exposed rats were treated with 50 mg/kg Kam from postnatal day (PND) 30 to PND 60. Then, Y-maze and Morris water maze have been used to detect the spatial memory in all groups of rats. Hematoxylin and eosin (HE) staining and Nissl staining were used to analyze the neuronal structure damages. The results found Kam treatment improved the learning and memory ability and alleviated hippocampal neuronal pathological damages. Besides, Kam could significantly reverse the synaptic transmission related protein expression including PSD95 and NMDAR2B. Further research found that Kam downregulated autophagy markers, P62, ATG5, Beclin1, and LC3-II. Furthermore, 3-MA, autophagy inhibitor, increased the levels of NMDAR2B and PSD95 in Pb-induced PC12 cells, indicating Kam alleviated Pb-induced neurotoxicity through inhibiting autophagy activation. Our results showed that Kam could ameliorate Pb-induced cognitive impairments and neuronal damages by decreasing Pb-induced excess autophagy accumulation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel and recyclable ZIF-90@CS/SA hybrids were successfully synthesized. • Maximum adsorption capacity of Pb and Co by ZIF-90@CS/SA was 1.24 × 10−3 mol/g and 1.69 × 10−3 mol/g, respectively. • ZIF-90@CS/SA displayed remarkable stability in the elimination of Pb and Co. • Surface complexation and electrostatic attraction were primary interactive mechanisms. • Long-term field studies on Pb and Co behaviors in water medium were required. Efficient elimination of heavy metals contaminations can be extensively concerned by utilizing environmental-friendly adsorbents with pursuing high adsorption capacity and reducing the treatment costs of industrial sewage. Herein, the core–shell structured chitosan/sodium alginate polysaccharide polymers loading zeolite imidazolate framework-90 beads (ZIF-90@CS/SA) were successfully synthesized and analyzed to obtain efficient enrichment performances for Pb and Co. The ZIF-90@CS/SA beads were multifariously characterized through the superficial micropore structures, which included both before and after adsorption performance of Pb and Co from the macroscopical experiments. The optimal weight ratio of chitosan/sodium alginate was chosen 1:2 to prepare ZIF-90@CS/SA beads by drop-method, and then adsorption experiments of Pb and Co were also conducted under various water chemistry conditions. The especial adsorption equilibrium time for the elimination of Pb and Co through the ZIF-90@CS/SA beads was 2.5 h and 3.5 h respectively, which was in accordance with pseudo-second order pattern. The maximal adsorption capacity was respectively 1.24 × 10−3 mol/g for Pb and 1.69 × 10−3 mol/g for Co, which considerably improved in comparison with many previously reported adsorbents. The adsorption mechanisms of ZIF-90@CS/SA beads with Pb and Co were dominated by the surface complexation, ion exchange and electrostatic attraction. According to macroscopical experimental studies, the ZIF-90@CS/SA beads have promising applications in the field of sewage treatment with highly efficient enrichment, advantageous regeneration and purfication of numerous heavy metal contaminants. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pb(II) removal capacity of the BC-TJ6 composite was higher than biochar and strain. • BC-TJ6 sequestrated Pb(II) through ion exchange and complexation. • Hydroxyl and carboxyl groups contribute most to Pb(II) adsorption on BC-TJ6. • Pb-OOC and Pb-O bond structures were responsible for Pb binding with BC-TJ6. Microbial immobilization is a new strategy for bio-remediation of heavy metals. However, information regarding immobilization of wild resistant bacteria onto biochar for heavy metal separation is limited. This study proposed the use of wild-resistant bacteria TJ6 in combination with biochar produced from agricultural waste (BC-TJ6) for Pb removal and investigated the associated mechanisms using Fourier transform infrared spectroscopy (FT-IR), energy dispersive spectroscopy (EDS), and X-ray photoelectron spectroscopy (XPS). Compared with the theoretical adsorption capacity according to the linear combination calculating by the mass ratio and adsorption capacity of individual component in the composite material, the actual adsorption capacity of BC-TJ6 for Pb(II) was increased by 73.54%. Specifically, the bridge between the bacteria and biochar of Pb(II) may explain the higher observed adsorption capacity of BC-TJ6 compared to theoretical values. EDS analysis based on electron micrograph showed that Pb(II) adsorbed onto TJ6 strain was 0.48%, while that onto biochar component was 0.14%. It indicated that the resistant bacteria contributed more to the adsorption of Pb(II) in BC-TJ6 composites. The FT-IR analysis suggested that the amide, carboxyl, and hydroxyl groups on the surface of the composite were involved in the adsorption of Pb(II). Further, XPS analysis demonstrated that Pb-O (42.12%) and Pb-OOC (27.6%) were the main Pb-molecular structures bound to the surface of the composite. This study is significant for improving the understanding of biochar-wild resistant bacterial combinations for heavy metal adsorption, and can provide guidance for the use of biochar-microbial remediation of heavy metal pollution. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pb causes a decrease in both survival rate and weight gain in Pardosa laura. • Pardosa laura uses superoxide dismutase and catalase to alleviate the damages. • DEGs are mainly involved in oxidoreductase, transmembrane, lipid and cell repair. As a raw material commonly used in industrial production, Pb is often found in the released waste, posing a serious threat to ecosystem and human. Pardosa laura (Araneae: Lycosidae) is one of the most dominant species of spider found in farmland ecosystem and plays a very important role in Pb transfer among the food web. To comprehensively understand the toxicological effects of Pb on spider, we delivered Pb to Pardosa laura through diet, and investigated the Pb effect on spider growth, antioxidase activities and transcriptome. Specifically, Pb hindered the spider growth and resulted in a reduced survival rate. Superoxide dismutase and catalase activities were enhanced in the Pb-exposed spider, while no significant change was found in the glutathione S-transferase activity. 117 up-regulated genes and 60 down-regulated genes were identified in the Pb-exposed spider by using transcriptome sequencing, and these DEGs were mainly enriched in oxidoreductase activity, transmembrane transport, fat digestion and absorption, peptidase activity, apoptosis, peptidase activity and lysosome. The results of this study contribute to the better understanding of the molecular mechanisms underlying the spider response to Pb. [ABSTRACT FROM AUTHOR]

Lead (Pb) and zinc (Zn) have been discharged into environment and may negatively impact ecological security. Rhizobia has gained attention due to their involvement in the restoration of metal polluted soils. However, little is known about the responses of rhizobia under Pb and Zn stress, especially the roles played by extracellular polymeric substances (EPS) in the resistance of these two metals. Here, Sinorhizobium sp. C10 was isolated from soil around a mining area and was exposed to a series of Pb/Zn treatments. The cell morphology and surface mineral crystals, EPS content and fluorescent substances were determined. In addition, the extracellular polysaccharides and proteins were characterized by attenuated total reflection infrared spectroscopy (ATR-IR) and X-ray photoelectron spectroscopy (XPS). The results showed that Zn stress induced the synthesis of EPS by C10 cells. Functional groups of polysaccharides (C O) and proteins (C–O/C–N) were involved in complexation with Zn. In contrast, C10 resisted Pb stress by forming lead phosphate (Pb 3 (PO 4) 2) on the cell surface. Galactose (Gal) and tyrosine played key roles in resistance to the Zn toxicity, whereas glucosamine (N-Glc) was converted to glucose in large amounts during extracellular Pb precipitation. Together, this study demonstrated that C10 possessed different strategies to detoxify the two metals, and could provide basis for bioremediation of Pb and Zn polluted sites. [Display omitted] • Sinorhizobium sp. C10 responded differently upon Pb and Zn exposure. • C10 secreted more EPS to form complex with Zn to reduce its toxicity. • Pb was detoxified through mineralization on the C10 cell surface. • Glucosamine and galactose were key monosaccharides of EPS against Pb/Zn stress. [ABSTRACT FROM AUTHOR]

[Display omitted] • Chronic Pb exposure decreased the serum butyrate content. • Supplementation with butyrate restored the Pb-induced memory deficiency. • Butyrate alleviated Pb-induced neuroinflammation by inhibiting STAT3 signaling. • Butyrate restored Pb-blunted BDNF expression via ACSS2-H3K9ac signaling. Lead is an environmentally widespread neurotoxic pollutant. Although the neurotoxicity of lead has been found to be closely associated with metabolic disorders, the effects of short-chain fatty acids on the neurotoxicity of lead and its mechanisms have not yet been explored. In this study, the results of open field tests and Morris water maze tests demonstrated that chronic lead exposure caused learning and memory deficits and anxiety-like symptoms in mice. The serum butyric acid content of lead-treated mice decreased in a dose-dependent manner, and oral administration of butyrate significantly improved cognitive memory impairment and anxiety symptoms in lead-exposed mice. Moreover, butyrate alleviated neuroinflammation caused by lead exposure by inhibiting the STAT3 signaling in microglia. Butyrate also promoted the expression of acetyl-CoA synthetase ACSS2 in hippocampal neurons, thereby increasing the content of acetyl-CoA and restoring the expression of both histone H3K9ac and the downstream BDNF. We also found that the median butyric acid concentration in high-lead exposure humans was remarkably lower than that in the low-lead exposure humans (45.16 μg/L vs. 60.92 μg/L, P < 0.01), and that butyric acid significantly mediated the relationship of lead exposure with the Montreal cognitive assessment scores, with a contribution rate of 27.57 %. In conclusion, our results suggest that butyrate supplementation is a possible therapeutic strategy for lead-induced neurotoxicity. [ABSTRACT FROM AUTHOR]

• HDAC4 was up-regulated by Pb exposure in vivo and in vitro. • Upregulation of HDAC4 damaged neurite outgrowth of the neural cell following Pb exposure. • Pb exposure induced the nuclear accumulation of HDAC4 in neural cells. • The Pb-induced nuclear accumulation of HDAC4 was ascribed to the increase of PP1. Lead (Pb) is an environmental contaminant that primarily affects the central nervous system, particularly the developing brain. Recently, increasing evidence indicates the important roles of histone deacetylases (HDACs) in Pb-induced neurotoxicity. However, the precise molecular mechanisms involving HDAC4 remains unknown. The purpose of this study was to investigate the role of HDAC4 in Pb-induced neurotoxicity both in vivo and in vitro. In vitro study, PC12 cells were exposed to Pb (10 μM) for 24 h, then the mRNA and protein levels of HDAC4 were analyzed. In vivo study, pregnant rats and their female offspring were treated with lead (50 ppm) until postnatal day 30. Then the pups were sacrificed and the mRNA and protein levels of HDAC4 in the hippocampus were analyzed. The results showed that HDAC4 was significantly increased in both PC12 cells and rat hippocampus upon Pb exposure. Blockade of HDAC4 with either LMK-235 (an inhibitor of HDAC4) or shHDAC4 (HDAC4-knocking down plasmid) ameliorated the Pb-induced neurite outgrowth deficits. Interestingly, HDAC4 was aberrantly accumulated in the nucleus upon Pb exposure. By contrast, blocking the HDAC4 shuffling from the cytosol to the nucleus with ΔNLS2-HDAC4 (the cytosol-localized HDAC4 mutant) was able to rescue the neuronal impairment. In addition, Pb increased PP1 (protein phosphatase 1) expression which in turn influenced the subcellular localization of HDAC4 by dephosphorylation of specific serine/threonine residues. What's more, blockade of PP1 with PP1-knocking down construct (shPP1) ameliorated Pb-induced neurite outgrowth deficits. Taken together, nuclear accumulation of HDAC4 by PP1-mediated dephosphorylation involved in Pb-induced neurotoxicity. This study might provide a promising molecular target for medical intervention with environmental cues. [ABSTRACT FROM AUTHOR]

• High Pb, Cd levels observed in semen of infertile tea-garden workers of Assam, India. • Anomalous oxidative stress and sperm parameters were observed in their semen. • Varied metal levels in semen caused relative p53 and Akt fluctuations in sperm cells. • Relative p53, Akt level in sperm cells determined the fertility outcome of workers. The aim of this study was to evaluate the impact of Lead (Pb) and Cadmium (Cd) exposure at the molecular level on the reproductive status of tea garden workers in North-East India. Using semen samples, we experimentally determined sperm analysis as well as oxidative stress parameters in all samples and evaluated the expression levels of apoptotic and cell survival proteins [p53, phospho-Akt, nuclear factor-κB (NF-κB, p50 subunit) and B cell lymphoma 2 (Bcl2)]. Our data revealed significant differences in the average heavy metal concentrations and various semen analysis profile between the infertile and normal groups. Increasing Pb and Cd concentrations in semen samples of patients showed positive associations with increasing number of multiple defects in sperm and the level of seminal oxidative stress markers in the high Pb and Cd concentration groups. These groups also exhibited positive correlations between high metal concentrations and the average p53 expression levels, but negative correlations with the mean p-Akt cascade protein levels in sperm cells. In the low Pb and Cd concentrations groups, we also observed reverse mean range and correlation patterns. Therefore, our findings may suggest that graded levels of metal exposure significantly influence the relative fluctuation in the levels of p53 and Akt cascade proteins in the sperm cells of infertile subjects. Furthermore, this may be a regulating factor of sperm cell fate, in turn, determining the fertility outcome of the men working in the tea gardens. [ABSTRACT FROM AUTHOR]

Three low-cost adsorbents (purified raw attapulgite (A-ATP), high-temperature-calcined attapulgite (T-ATP), and hydrothermal loading of MgO (MgO-ATP)) were prepared as adsorbents for the removal of Cd(II) and Pb(II). By evaluating the effect of the initial solution pH, contact time, initial solution concentration, temperature and coexistence of metal ions on Cd(II) and Pb(II) adsorption, the experimental results showed that MgO-ATP was successfully prepared by hydrothermal reaction and calcination as well as appearing to be a promising excellent adsorbent. At an initial pH of 5.0, A-ATP, T-ATP and MgO-ATP reached maximum adsorption amounts of 43.5, 53.9 and 127.6 mg/g for Pb(II) and 10.9, 11.2, and 25.3 mg/g for Cd(II) at 298 K, respectively. The Cd(II) adsorption on A-ATP was fitted by the Freundlich model, while the adsorption of Pb(II) and Cd(II) on T-ATP and MgO-ATP as well as Pb(II) adsorption on A-ATP agreed with the Langmuir model. All kinetic experimental data favored pseudo second-order model. The calculated thermodynamic parameters suggested that Pb(II) adsorption onto MgO-ATP was spontaneous and exothermic. When considering foreign metal ions, the three adsorbents all presented preferential adsorption for Pb (II). Chemical adsorption had a high contribution to the removal of Cd(II) and Pb(II) by modified attapulgite. In summary, the adsorption was greatly enhanced by the hydrothermal loading of MgO. It aimed to provide insights into the MgO-ATP, which could be able to efficiently remove Cd(II) and Pb(II) and serve as an economic and promising adsorbent for heavy metal-contaminated environmental remediation. [ABSTRACT FROM AUTHOR]

High-K granitoids are among the most abundant rock types in many Archean cratons. Late Neoarchean monzogranitic to syenogranitic gneisses with high-K affinities are widely distributed in the Anshan, Suizhong, Qinhuangdao, and Aolaishan areas on the northeastern margin of the North China Craton (NCC). In this contribution, we present an integrated study of zircon U–Pb–Hf–O isotopic compositions and whole-rock elemental compositions of amphibolites and trondhjemitic and monzo–syenogranitic gneisses of the Jinzhou area in the metamorphic basement of eastern Hebei–western Liaoning, with the aim of constraining their petrogenesis and geodynamic setting. Emplacement ages of the amphibolites and trondhjemitic–monzogranitic gneisses are 2543 ± 27, 2532 ± 19, and 2513 ± 7 Ma, respectively. The amphibolites are tholeiitic in composition with SiO 2 contents of 49.7–50.8 wt%, variable degrees of light rare-earth-element (LREE) enrichment and high-field-strength element (HFSE) depletion, and high zircon εHf(t) values of +2.6 to +6.3, suggesting a depleted lithospheric mantle origin. The major- and trace-element compositions of the trondhjemitic gneisses are similar to those of the low-pressure tonalite–trondhjemite–granodiorite (TTG) suite. The zircon Hf (εHf(t) = +1.6 to +3.9) and O (δ18O = +3.76‰ to +5.73‰) isotopic compositions of the trondhjemitic gneisses indicate a juvenile basaltic source at the base of a thickened magmatic arc. The monzogranitic gneisses differ from their TTG counterparts in that they have lower SiO 2 and higher MgO, K 2 O, and incompatible-element (especially Ba, Th, Sr, P, and LREE) contents. They also have slightly evolved zircon εHf(t) values (+0.6 to +3.8) and higher δ18O values (+4.69‰ to +6.13‰). These features suggest that the monzogranitic gneisses represent sanukitoid-type rocks, with a mantle source modified by crust-derived melts. The weakly deformed syenogranitic gneisses are characterized by high SiO 2 and K 2 O, and very low MgO, Cr, and Ni contents, suggesting that they were formed by partial melting of local TTG rocks. Our results, together with those of previous investigations, suggest that the 2554–2513 Ma low- to high-K magmatism in the Jinzhou area most likely originated in an arc–back-arc tectonic setting on the northern margin of the NCC. The large volumes of high-K granitoids in eastern Hebei–western Liaoning are related to extensive mantle–crust interactions and crustal reworking in such a setting. Unlabelled Image • 2543 Ma amphibolites originated from a mantle wedge slightly metasomatized by slab-derived fluids. • 2532 Ma Trondhjemitic gneisses originated from a juvenile basaltic source at the base of a thickened magmatic arc. • 2513 Ma monzogranitic gneisses originated from an enriched mantle metasomatized by sediment-derived melts. • Ca. 2.55–2.49 Ga low- to high-K magmatism in the Jinzhou area were most likely formed in an arc-back-arc tectonic setting. [ABSTRACT FROM AUTHOR]

Shooting activities is an important source of Pb in contaminated soils. Lead accumulates in superficial soil horizons because of its low mobility, favouring its uptake by plants and representing a high transference risk to the trophic chain. A combination of phytoremediation with nanoremediation techniques can be used to recover firing range soils and decrease the mobility, bioavailability and toxicity of Pb. This study examines in depth the changes in Pb behaviour in firing range soils by adding hydroxyapatite nanoparticles (HANPs). These nanoparticles (NPs) may immobilise Pb and improve the quality of these areas. The use of HANPs and the Pb effects were assessed in three different species (Sinapis alba L., Lactuca sativa L. and Festuca ovina L.), focusing on their germination and early growth, through phytotoxicity assays. Single extractions with CaCl 2 (0.01 M) in soils treated with HANPs show that these NPs retained Pb and reduced highly its availability and mobility. HR-TEM and TOF-SIMS were used to determine the interactions between HANPs and Pb, as well as with soil components. According to TOF-SIMS and HR-TEM/EDS analysis, Pb was mainly retained by HANPs but also associated lightly to organic matter, Fe compounds and silicates. Phytotoxicity assays exposed that S. alba , L. sativa and F. ovina were able to germinate and develop in the firing range soils despite the high available Pb contents before adding HANPs. After adding HANPs, Pb retention increased, favouring the germination and the growth of roots in the three species. These results suggest that HANPs can be used to decrease the availability and the toxicity of Pb without negative effects in the species growth. Accordingly, the combination of phytoremediation and nanoremediation techniques can be a great tool to stabilise these soils, avoiding the Pb transfer to nearby areas and its entry in the trophic chain. Unlabelled Image • HANPs reduce efficiently the available Pb contents in firing range soils. • HANPs favour the germination and root growth of S. alba , L. sativa and F. ovina. • TOF-SIMS/HR-TEM allow to assess the interactions among HANPs, Pb and soil components. • Pb mobility, availability and toxicity decrease greatly after treatment with HANPs. • Nanoremediation and phytoremediation can be effective to recover firing range soils. [ABSTRACT FROM AUTHOR]

The application of analytical chemistry to the exploration of the World Cultural Heritage represents a major challenge in that most protocols and strategies are invasive and require micro-sampling. We report a novel methodology for harvesting material deposited on the surface of ancient documents while avoiding their damage or contamination. The technology here described relates to the capture of metals on these specimens. It is based on the use of plastic films (ethylene vinyl acetate, EVA) impregnated with different metal chelators (sodium 2,3-dimercapto-1-propanesulfonate, DMPS, meso-2,3-dimercaptosuccinic acid, DMSA and ethylene diamino tetra acetic acid, EDTA, as calcium salt), for harvesting from surfaces of different supports potential traces of metals therein deposited. The EVA film technology has been used to explore the pages of a manuscript written by Kepler concerning the movements of the moon and catalogued under the title "Hipparchus" at the Archives of the Russian Academy of Sciences (St. Petersburg branch). The EVA-based chelating diskettes were able to capture very significant amounts of different metals, namely: Au, Ag, Hg, As, Pb, suggesting that Kepler, well known as astronomer, astrologist, mathematician and Lutheran theologian, might have started practicing alchemy, a pseudo-chemical science he had learned from his colleague Tycho Brahe in Prague. Image 1 • The EVA film technology for monitoring traces of past life in manuscripts. • An Eva diskette with chelating agents for harvesting metals. • As, Pb, Ag, Au, Hg metal quantitation discovers potential Kepler's work on alchemy. • Four types of EVA films expand our ability of exploring the World Cultural Heritage. [ABSTRACT FROM AUTHOR]

The use of tree rings to record changes in lead (Pb) deposition levels and pollution sources has produced contrasted results depending on tree species and sites. In this study, Pb concentrations and isotopic ratios (206Pb/207Pb, 208Pb/206Pb and 206Pb/204Pb) were analyzed in the exchangeable (0.05M HCl extraction) and the residual (concentrated HNO 3 extraction) fractions of sugar maple's tree rings at four eastern Canada forest sites. Above 90% of tree ring Pb was associated with the residual fraction, reflecting strong binding to wood, thus suggesting low radial mobility in sugar maple. After an increase in the first part of the 20th century, wood Pb concentration declined from the 1970s–80s to nowadays for most sampled trees to reach levels similar or even lower than in the early 20th century. This decline was paralleled by a slight decrease in 206Pb/207Pb ratio, reflecting a decrease in Pb pollution in the last decades. Our isotopic data suggest the contribution of USA sources declined by 20–40% at three out of the four study sites since the early 1900's. These observed trends align with findings reported in previous studies and reveal that sugar maple may be a good tree species model to record Pb atmospheric pollution. Further study must be conducted to validate these findings, especially to estimate the contribution of root vs. aboveground biomass to Pb uptake. • We assessed the possibility of using maple sugar tree rings to trace historical Pb deposition in eastern Canada. • ∼100% of Pb was associated with the residual fraction, suggesting radial mobility in the wood is low. • Pb concentration increased from early 1900's to the 1970s–80s and then strongly declined. • Isotopic data show that the contribution of US sources declined by 20–40% at most sites since the early 1900's. • This study suggests sugar maple might be a good tree species model to record historical atmospheric pollution levels. [ABSTRACT FROM AUTHOR]

Water pollution is a major global challenge due to the fast expansion of industrial activities and the increasing human population. Certain heavy metals can be exceedingly hazardous and contribute significantly to water contamination. In this study, iron oxide nanoparticles (IONPs) were synthesized using cyanobacteria extract to remove heavy metals (Cd and Pb) from the wastewater. To characterize the IONPs, several analytical techniques were employed such as Ultraviolet–visible spectroscopy revealed a SPR (surface plasmon resonance) peak at 348 nm and FTIR (Fourier transform infrared) spectral analysis showed the OH, C–H and S=O functional groups which confirmed the biomolecules responsible for the biogenic synthesis and stability. The surface morphology of the biogenic IONPs was investigated using SEM (scanning electron microscopy) which reveled their nearly spherical or cubic shape. Additionally, XRD (X-ray diffraction) analysis confirmed the crystallinity of IONPs, with a crystalline size measuring 18.21 nm. Effects of contact time, pH, initial metal ions concentrations, and IONPs dosage were studied on the adsorption of Cd and Pb ions. Different adsorption kinetics and isotherm models were applied to the experimental data. Pseudo second-order kinetic and Langmuir isotherm models were well fitted to the adsorption of Cd and Pb onto the IONPs. Higher correlation coefficients (R2) values of Langmuir isotherm (R2: 0.990 for Cd and Pb adsorption) and Pseudo second-order kinetic (R2: 0.998 and 0.999 for Cd and Pb adsorption, respectively) were found, which indicated the favorable interaction between the metal ions and adsorbent. Langmuir isotherm calculated maximal adsorption capacities of 105.932 and 118.764 mg/g for Cd and Pb, respectively. Recyclability of IONPs was conducted and after five adsorption/desorption cycles, IONPs retained their adsorption efficiency with negligible decline. After five cycles, IONPs removal efficiency was up to 80.41 and 88.35 % for Cd and Pb, respectively. Results of this study indicate that cyanobacteria-mediated IONPs were efficient adsorbent for Pb and Cd removal from contaminated aqueous solution. [ABSTRACT FROM AUTHOR]

The widespread environmental heavy metal, Pb, is renowned for inducing irreversible damage to human health. Lignin, an original fiber, emerges as a promising natural candidate for mitigating lead toxicity owing to its exceptional adsorption capacity and biocompatibility. In this study, we conducted an investigation into the potential therapeutic effects of lignin derived from the bamboo (Dendrocalamus Latiforus) shoot shell (BSS-AAL) in alleviating Pb-induced oxidative stress and hypercholesterolemia in hamsters. Our findings demonstrated the remarkable ability of BSS-AAL to reduce Pb accumulation by 27–40% in plasma and 13–84% in tissues. Furthermore, BSS-AAL exerted reparative effects on the antioxidant system, evidenced by substantial reductions in plasma total cholesterol levels by at least 35% and hepatic cholesterol levels by an impressive 66%. Intervention with BSS-AAL also led to favorable alterations in the richness of key microbial genera, including norank_f__Erysipelotrichaceae , unclassified_f__Atopobiaceae , and norank_f__Eubacteriaceae , which are associated with modulating malonaldehyde accumulation, hepatic cholesterol 3-hydroxy-3-methylglutaryl coenzyme A reductase activity, as well as short chain fatty acids synthesis. These findings substantiated BSS-AAL played a vital role in effectively modulating Pb-induced oxidative stress and hypercholesterolemia by reducing Pb accumulation and favorably influencing gut microbiota. [Display omitted] • Pb exposure showed symptoms in oxidative stress, lipid metabolism, and gut flora. • BSS-AAL lowered Pb accumulation via chelating interaction. • BSS-AAL repaired the antioxidant system. • MDA accumulation and HMGR activity in livers were modulated by gut microbiota. • Gut microbiota involved in acetate were associated with the relief of Pb toxicity. [ABSTRACT FROM AUTHOR]

Lead (Pb) exposure is well recognized as a significant environmental factor associated with the high incidence of cardiovascular diseases. However, the carriers and molecular targets of Pb in human blood remain to be understood, especially for a real Pb exposure scenario. In this study, a total of 350 blood samples were collected from the smelting workers and systematically analyzed using metallomics and metalloproteomics approaches. The results showed that the majority of Pb (∼99.4%) could be presented in the blood cells. Pb in the cytoplasm of blood cells accounted for approximately 83.1% of the total blood Pb, with nearly half of Pb being bound to proteins. Pb-binding proteins in the blood of workers were identified as hemoglobin, catalase, haptoglobin, δ-aminolevulinic acid dehydratase, and peroxiredoxin-2. Multiple linear regression analysis demonstrated that higher levels of Pb bound to proteins (Mix-bound Pb and Protein-bound Pb) were positively associated with higher systolic blood pressure (p < 0.05). However, the association between blood lead level, Pb levels in the blood cells and systolic blood pressure was not observed (p > 0.05). This study suggested that Pb bound to proteins could be a suitable biomarker for indicating the potential risk of occupational hypertension. [Display omitted] • 99.4% of Pb was concentrated in blood cells of workers, and primarily (83.1%) existed in cytoplasm, the distribution patterns of Pb in the blood was affected by workplaces. • Pb selectively bound to proteins in blood cells of workers, including hemoglobin, catalase, haptoglobin, δ-aminolevulinic acid dehydratase, and peroxiredoxin-2. • Protein-bound Pb is an earlier and more sensitive indicator than blood lead levels, as it is positively correlated with systolic blood pressure, indicating the risk of hypertension. [ABSTRACT FROM AUTHOR]

The dynamic reactions of uranium (U) with iron (Fe) minerals change its behaviors in soil environment, however, how the coexisted constituents in soil affect U sequestration and release on Fe minerals during the transformation remains unclear. Herein, coupled effects of lead (Pb) and dissolved organic matter (DOM) on U speciation and release kinetics during the catalytic transformations of ferrihydrite (Fh) by Fe(II) were investigated. Our results revealed that the coexistence of Pb and DOM significantly reduced U release and increased the immobilization of U during Fh transformation, which were attributed to the enhanced inhibition of Fh transformation, the declined release of DOM and the increased U(VI) reduction. Specifically, the presence of Pb increased the coprecipitation of condensed aromatics, polyphenols and phenols, and these molecules were preferentially maintained by Fe (oxyhydr)oxides. The sequestrated polyphenols and phenols could further facilitate U(VI) reduction to U(IV). Additionally, a higher Pb content in coprecipitates caused a slower U release, especially when DOM was present. Compared with Pb, the concentrations of the released U were significantly lower during the transformation. Our results contribute to predicting U sequestration and remediating U-contaminated soils. [Display omitted] • A lower U:Pb ratio enhanced the stability of U during Fh transformation. • The presence of Pb increased the coprecipitation of DOM molecules with Fh. • The concentration of the released U was significantly lower compared with Pb. • The coexistence of DOM and Pb slowed down U release from Fe (oxyhydr)oxides. [ABSTRACT FROM AUTHOR]

Myogenesis is a crucial process governing skeletal muscle development and homeostasis. Lead (Pb) exposure impaired the development and the health of bones, which slows the growth of children. However, it is far from clear what exactly the effects of Pb on skeletal muscle development are. In this study, C2C12 cells are commonly used as an in vitro model of muscle regeneration due to their ability to transition from a proliferative phase into differentiated myofibers. The dose of 1, 5, and 10 μM Pb were adopted to study the toxicity of Pb on C2C12 proliferation and differentiation. First, the effects of Pb on cell viability were detected and the results demonstrated that 5 μM and 10 μM Pb exposure decreased cell viability, while 1 μM Pb exposure has no obvious effects on cell viability. Then, 1–10 μM Pb exposure seriously reduced the C2C12 myoblasts differentiation, with the decrease of myogenic differentiation marker genes expression, including Muscle creatine kinase (MCK), Myosin Heavy Chain 4 (MYH4), Myogenin (MYOG), Myogenic Differentiation (MYOD). What's more, it was found that the epigenetic modifier histone deacetylase-2 (HDAC2) was upregulated after Pb exposure on C2C12 myoblasts. Further studies conclusively showed knockdown of HDAC2 ameliorated Pb-damaged C2C12 myoblasts differentiation, indicating HDAC2 plays a vital role in the Pb-induced C2C12 myoblasts differentiation deficits. In summary, these results demonstrated that Pb exposure inhibited C2C12 myoblasts differentiation by regulating HDAC2. [Display omitted] • Pb exposure retarded myoblast differentiation of C2C12 cells. • Pb exposure upregulated HDAC2 expression during C2C12 myoblast differentiation. • HDAC2 regulated Pb-induced C2C12 myoblast differentiation inhibition. [ABSTRACT FROM AUTHOR]

Complex interactions have been established between nanoparticles (NPs) and heavy metals in real environments. Herein we used zebrafish embryos to investigate the influence of titanium dioxide NPs (n-TiO 2) on the uptake, bioconcentration, and depuration, and toxicity of Pb. The formation of n-TiO 2 –Pb complexes was confirmed in an exposure suspension. An increase in Pb bioconcentration was observed in zebrafish embryos upon co-exposure to n-TiO 2 and Pb; moreover, n-TiO 2 –Pb complexes could be found in the embryos, indicating the bioavailability of NPs. However, there was no difference in the depuration rates of Pb in the presence of n-TiO 2. Metallothionein (MT) content was significantly increased upon exposure to Pb alone, and the content significantly increased even further upon co-exposure. A downregulation in the expression levels of the neurodevelopment-related genes gfap , syn2α , and elavl3 was observed in the embryos, and we also noted a reduction in the swimming speed of and the total distance traveled by the larvae. To summarize, our results indicate that n-TiO 2 can act as an effective carrier of Pb to enhance its uptake, bioavailability, and toxicity in zebrafish embryos. • n-TiO 2 -Pb complexes were formed in co-exposure suspension. • Bioconcentration and bioavailability of Pb was increased by n-TiO 2 in zebrafish embryos. • Neurotoxicity of Pb was enhanced in the presence of n-TiO 2. [ABSTRACT FROM AUTHOR]

The Chamuhan Granite is located in the eastern part of the Central Asian Orogen where it crops out as an elongated, NE-trending composite monzogranite. The pluton consists of two phases with a fine – grained monzogranite (G2) at depth in sharp contact with a medium – grained monzogranite (G1) above. The medium-grained monzogranite can be subdivided into G1a and G1b based on the degree of metasomatism affecting it, with the G1b being more altered. Tungsten–molybdenum mineralisation is hosted by quartz (−fluorite) veins or forms disseminated sulfides in G1a, indicating a genetic association between the monzogranite and ore. Magmatic zircons from G1a yield a weighted mean age of 144 ± 2 Ma, and hydrothermal zircons from G1a yield a weighted mean age of 143 ± 1 Ma, indicating that the hydrothermal zircons are very close in age to the medium-grained monzogranite. Monazite grains yield U – Pb isotope ages of 138 ± 3 Ma for G1a, 137 ± 1 Ma for G1b, and 139 ± 2 Ma for the fine-grained monzogranite (G2) phase. These dates are the same within analytical error, and are coeval with the molybdenite Re – Os weighted mean age of 140 ± 2 Ma, indicating that the monazite and molybdenite were deposited during hydrothermal alteration. The Chamuhan Granite is geochemically a metaluminous to slightly peraluminous high – K calc-alkaline granite, and is especially characterised by its REE tetrad pattern and a huge Eu depletion that are accompanied by a non – "Charge-and Radius-Controlled" (CHARAC) trace element behaviour. This and the O-isotopic data from the granite phases are indicative of a highly differentiated magma that interacted strongly with a co–existing fluid emanating from the magma during the late stage of its crystallisation. The interaction between the magma and related hydrothermal fluid resulted in the enrichment of W–Mo(–Nb–Ta–Th–U–Hf–Rb–Y). All the studied granitic rocks have homogeneous initial isotope values with positive εNd(t) values of 0.1–3, and T DM2 dates between 924 and 691 Ma. This is consistent with granites derived from a pre-existing juvenile crust derived from a depleted mantle during the Neoproterozoic. The molybdenite in the Chamuhan W – Mo deposit has a narrow δ34S VCDT range of 0.1–1.6‰ characteristic of a magmatic origin, and the Pb isotopic compositions with 206Pb/204Pb ratios between 18.298 and 18.882, 207Pb/204Pb ratios between 15.494 and 15.538 and 208Pb/204Pb ratios between 38.046 and 38.206, are similar to the calculated initial Pb isotopic ratios of the Chamuhan Granite. We thus suggest that there is an intimate relationship between the Chamuhan Granite and mineralisation, and that the mineralising process is related to a post-collisional extensional event following the formation of an over-thickened continental crust and during closure of the Mongol-Okhotsk and Paleo-Pacific oceanic plates. • The Chamuhan Granite is a highly fractionated granite with REE tetrad effect. • The interaction between magma and fluid resulted in the enrichment of W and Mo. • The Nd – Hf isotope data indicate the granite was sourced from a juvenile crust. [ABSTRACT FROM AUTHOR]