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Bauxite deposits are an important source of Al and also host a variety of critical metals, including rare earth elements (REEs). However, the parent rocks of bauxite deposits generally have low REE contents, leading to uncertainty over the REE sources and enrichment mechanisms. In this study, we report high REE (2095 ppm; Ce = 1340 ppm) contents in the Lijiatian bauxite deposit in Luxi County, western Hunan Province, South China. The Lijiatian bauxite deposit is the largest deposit in Hunan Province, with a total Al resources exceeding 7 × 106 tons. The ore-bearing strata in the lower Permian Liangshan Formation (ca. 275 Ma) are comprised a 3–5-m-thick bauxite layer (bauxite ore/clay) and an underlying 4–8-m-thick Fe layer (Fe ore/Fe-rich clay). The high REE contents in the bauxites can be attributed to the widespread presence of bastnäsite. The bastnäsite commonly coexists with authigenic chlorite, which formed at temperatures of 221–285 °C, indicative of a hydrothermal origin. Uranium–Pb dating of the bastnäsite yielded an age of 141.4 ± 7.0 Ma, indicating a hydrothermal overprint occurred during the Early Cretaceous, which resulted in the enrichment of REEs in the bauxites. The high contents of REEs, Ba, and P in the Cambrian Niutitang Formation black shales indicate it was a potential source of these elements for bastnäsite and coexisting barite and apatite. The deep-seated hydrothermal fluids (enriched in HF, CO 2 , and H 2 S) associated with the late Yanshanian extensional tectonic event in South China (155–123 Ma) ascended along fractures. The ascending fluids interacted with the black shales, extracting REEs, Ba, and P. When the fluids reached a certain depth, they mixed with the infiltrating basinal waters to form a mineralising fluid. The fluid then migrated towards the bauxite layers, underwent cooling and depressurisation, and precipitated bastnäsite, barite, apatite, and chlorite. We propose that a hydrothermal event led to the enrichment of REEs in the bauxites in Hunan Province. Considering the scarcity of REEs in the parent rocks of bauxites worldwide, hydrothermal activity likely has a key role in REE enrichment in bauxites. [Display omitted] • The main mineral hosting REE (Ce) in Permian bauxite from southern China is Bastnäsite. • The bastnäsite formed during the Cretaceous period due to hydrothermal fluid activity. • The REEs are source from the basement black shale. [ABSTRACT FROM AUTHOR]

The days that precede Valentine's Day are characterized by extensive gift shopping activities all across the globe. In China, where much shopping takes place online, there has been an explosive growth in e-commerce sales during Valentine's Day over the recent years. This exploratory study investigates the extent to which each product category and each shopper group can exhibit romantic love within China's e-market throughout the 2 weeks leading up to 2019 Valentine's Day. Massive data from Alibaba, the biggest e-commerce retailer worldwide, are utilized to formulate an innovative romance index (RI) to quantitatively measure e-romantic values for products and shoppers. On this basis, millions of shoppers, along with their millions of products purchased around Valentine's Day, are analyzed as a case study to demonstrate their love consumption and romantic gift-giving. The results of the analysis are then illustrated to help understand Chinese e-romance based on the perspectives of different product categories and shopper groups. This empirical information visualization also contributes to improving the segmentation, targeting, and positioning of China's e-market for Valentine's Day. [ABSTRACT FROM AUTHOR]

Nitrous oxide (N 2 O), a potent greenhouse gas, significantly contributes to the carbon footprint of wastewater treatment plants (WWTPs) and contributes significantly to global climate change and to the deterioration of the natural environment. Our understanding of N 2 O generation mechanisms has significantly improved in the last decade, but the development of effective N 2 O emission mitigation strategies has lagged owing to the complexity of parameter regulation, substandard monitoring activities, and inadequate policy criteria. Based on critically screened published studies on N 2 O control in full-scale WWTPs, this review elucidates N 2 O generation pathway identifications and emission mechanisms and summarizes the impact of N 2 O on the total carbon footprint of WWTPs. In particular, a linear relationship was established between N 2 O emission factors and total nitrogen removal efficiencies in WWTPs located in China. Promising N 2 O mitigation options were proposed, which focus on optimizing operating conditions and implementation of innovative treatment processes. Furthermore, the sustainable operation of WWTPs has been anticipated to convert WWTPs into absolute greenhouse gas reducers as a result of the refinement and improvement of on-site monitoring activities, mitigation mechanisms, regulation of operational parameters, modeling, and policies. [Display omitted] • Standard sampling locations, frequency or duration ensure accurate N 2 O monitoring. • N 2 O emissions in WWTPs contribute considerably to the total carbon footprint. • Parameters control: precise aeration and preferred conditions for microbial growth. • Future work should revisit trade-offs between improved TN removal and N 2 O reduction. [ABSTRACT FROM AUTHOR]

Mercury (Hg) is a widespread heavy metal causing various damages to health, while insufficient studies assessed its exposure risk across China. This study explored concentrations in food items and dietary exposure risks across China by comprehensively analyzing the researches on total Hg (THg) in eight food items and methylmercury (MeHg) in aquatic foods published between 1980 and 2021. According to the included 695 studies, the average THg concentration in all food items was 0.033 mg/kg (ranging from 0.004 to 0.185 mg/kg), with the highest concentration in edible fungi. The average daily dietary THg exposure from all foods was 12.9 μg/day. Plant-based foods accounted for 62.7% of the dietary THg exposure. Cereals and vegetables were the primary source of THg exposure. The MeHg concentration in aquatic foods was 0.08 mg/kg, and the average dietary exposure was 3.8 μg/day. Monte Carlo simulations of the dietary exposure risk assessment of THg and MeHg showed that approximately 6.4 and 7.0% of residents exceeded the health-based guidance value set by the European Food Safety Authority, with higher exposure risk in Southwest and South China. The nationwide target hazard quotient index of THg was greater than 1, suggesting that the non-carcinogenic risk of dietary exposure to THg needed further concern. In summary, this study has a comprehensive understanding of dietary Hg exposure risks across China, which provide a data basis for Hg exposure risk assessment and policy formulation. [Display omitted] • The average concentrations of total Hg in eight food items ranged from 0.004 to 0.185 mg/kg. • The average dietary total Hg exposure of Chinese residents was 12.9 μg/day. • Plant-based food contributed 62.7% to the dietary total Hg exposure. • The total Hg exposure risk in Southwest China needs to be focused on. [ABSTRACT FROM AUTHOR]

[Display omitted] Disability weights are crucial for quantifying health loss associated with non-fatal outcomes and were not well assessed in different countries, especially for specific cancer. Therefore, this study aimed to identify disability weights with a focus on specific cancer in a large Chinese population. Two types of web surveys were conducted, and 254 health states, including 30 new states for specific cancer, were investigated using paired comparison methods. The years lived with disability (YLDs) of cancer were calculated as the sum of the prevalence of each sequela of cancer multiplied by its relative disability weight. In total, 44,069 participants were eligible for the disability weights study. The disability weights of 254 health states were estimated. Among those, the disability weights of 18 specific cancer types varied greatly at diagnosis and primary treatment stage, with the value ranging from 0.619 (95% uncertainty interval (UI) 0.606–0.632) for brain cancer to 0.167 (95% UI 0.158–0.176) for oropharyngeal cancer. The discrepancy in YLDs calculated by different disability weights was high, and the largest gap for all cancer combined was approximately 30.14%. When calculated using the cancer-specific disability weights, a total of 1,967,830 (95% UI 1,928,880–2,008,060) YLDs of cancer were recorded in China. The disability weights of cancer varied greatly among cancer types and populations, which had considerable influence on the estimation of the disease burden. Cancer-specific disability weights could provide a more accurate evaluation of the cancer burden. [ABSTRACT FROM AUTHOR]

[Display omitted] • We focus on the oldest tin deposit in China using geology, geochemistry and geochronology methods; • Mineralization occurred between 851–844 Ma, corresponding to rift setting; • Sn-bearing granite is identified as originating from the reworking of Paleo- to Mesoproterozoic metasedimentary crust; • A high degree of differentiation is pivotal in facilitating the formation of tin-bearing granites; • This study highlights the significance of a metasediment-derived source and highly evolved, reduced, or ilmenite-series granitic magma in controlling the formation of granite-related Neoproterozoic tin mineralizations. The scarcity of Precambrian tin deposits in China has drawn significant interest to their formation. The Chahe tin deposit (26 Mt @ 0.38 % Sn), one of the oldest in China, provides a valuable opportunity to investigate the key factors controlling the development of such deposits. Situated along the western margin of the Yangtze craton in southwestern China, this deposit exhibits diverse mineralization types, including greisen cassiterite mineralizations located on top of the granitic cupola, skarn-cassiterite-axinite-quartz veins, and cassiterite-sulfide veins at the granite-limestone contact, and structurally controlled occurrences within siliciclastic metasedimentary rocks along secondary faults. Extensive U-Pb dating reveals that both barren and tin-bearing granites associated with the deposit share similar ages, ranging from 851 ± 4 Ma to 848 ± 4 Ma. These ages closely match, within error, the cassiterite U-Pb age of 843–853 Ma and the rutile U-Pb age of 859 ± 27 Ma for greisen veins/veinlets hosted in granite. Additionally, a cassiterite U-Pb age of 844 ± 9 Ma has been identified in the cassiterite–axinite–quartz veins hosted in the skarn. These findings provide direct evidence for the spatial, temporal, and genetic association of tin mineralization with Neoproterozoic Mosuoying granites. The granites in the region are categorized as peraluminous calc-alkali granites, characterized by high FeO, Ga/Al ratios, and zircon saturation temperatures, indicative of A-type granite features. In comparison to regional contemporaneous granites, the barren and tin-bearing granites exhibit high Rb/Ba and Rb/Sr ratios, variable ε Hf (t) values (–17.8 to + 3.1), and two-stage Hf model ages (T DM2) spanning from 2.6 to 1.5 Ga. These characteristics indicate a common source and origin through the reworking of Paleo- to Mesoproterozoic metasedimentary crust in response to the breakup of the Rodinia supercontinent. Simultaneously, they display low whole-rock Fe 2 O 3 /FeO and zircon Ce4+/Ce3+ ratios, consistent with those observed in typical Sn-bearing ilmenite-series granites globally. Notably, the tin-bearing granites manifest a highly fractionated nature, evident in their REE distribution patterns with a pronounced tetrad effect, as well as lower Nb/Ta and Zr/Hf ratios for twin elements. In summary, this study emphasizes the significance of a metasediment-derived source and the presence of highly evolved, reduced, or ilmenite-series granitic magma in the development of highly fractionated A-type granites associated with Neoproterozoic tin mineralization. These findings provide insights into the crucial factors controlling Neoproterozoic tin metallogenic events, shedding light on metallogenic processes and systematic exploration strategies for tin in Precambrian terranes. [ABSTRACT FROM AUTHOR]

[Display omitted] • 30 m3 anaerobic/aerobic/anoxic pilot-scale SBR system was first set up with sewage. • Total nitrogen and phosphate in effluent were 10.9 and 0.1 mg/L at 15.7℃. • The relative abundance of Competibacter and Tetrasphaera rose to 1.25% and 1.52%. • The contribution rate by endogenous denitrification was more than 43.3%. • Sludge reduction (17.1 %) and short aerobic time (6.0 h) helped to save energy. Removing nitrogen and phosphorus from low ratio of chemical oxygen demand to total nitrogen and temperature municipal wastewater stays a challenge. In this study, a pilot-scale anaerobic/aerobic/anoxic sequencing batch reactor (A/O/A-SBR) system first treated 15 m3/d actual municipal wastewater at 8.1–26.4 °C for 224 days. At the temperature of 15.7 °C, total nitrogen in influent and effluent were 45.5 and 10.9 mg/L, and phosphorus in influent and effluent were 3.9 and 0.1 mg/L. 16 s RNA sequencing results showed the relative abundance of Competibacter and Tetrasphaera raised to 1.25 % and 1.52 %. The strategy of excessive, no and normal sludge discharge enriched and balanced the functional bacteria, achieving an endogenous denitrification ratio more than 43.3 %. Sludge reduction and short aerobic time were beneficial to energy saving contrast with a Beijing municipal wastewater treatment. This study has significant implications for the practical application of the AOA-SBR process. [ABSTRACT FROM AUTHOR]

Many paleo-karstic bauxite deposits contain elevated concentrations of Ni and Co. It has been known that Co and Ni are dominantly hosted in sulfides, but it remains unclear how Ni and Co were incorporated into sulfides and what kind of physiochemical conditions were involved. The Maochang bauxite deposit, as one of the large Ni- and Co-bearing paleo-karstic bauxite deposits in Guizhou Province, southwest China, was selected to tackle these questions. Detailed mineralogical and sulfur isotopic analyses using integrated EBSD, EPMA, LA-ICPMS, and LA-MC-ICPMS methods revealed three stages of sulfide mineralization: stage I with pyrite (PyI), stage II with pyrite (PyII), millerite, sphalerite, chalcopyrite and violarite, and stage III with pyrite (PyIII), chalcopyrite and galena. The fine-grained, euhedral PyI has up to 0.79 wt% Ni and up to 0.53 wt% Co. In contrast, PyII, which replaced or overgrew PyI, exhibits high but variable Ni, Co and As contents, and is further divided into three sub-types: Ni-rich PyII-a (up to 16.54 wt% Ni, 0.94 wt% Co, and 0.38 wt% As) and PyII-b (up to 3.30 wt% Ni, 1.41 wt% Co, and 0.36 wt% As), and Co-rich PyII-c (up to 0.99 wt% Ni, 7.57 wt% Co, and 1.81 wt% As). PyIII is Ni- and Co-poor. Ni increases from PyI to PyIIa and PyIIb, and then decreases to PyIIc and PyIII, whereas Co remains at similar levels for PyI, PyIIa and PyIIb, significantly increases to PyIIc, and then drops abruptly to PyIII. δ34S V-CDT values vary dramatically from negative values for PyI (−6.9 to −16.6‰) to positive values for PyII-b (+19.4 to +22.8‰), sphalerite (+17.2 to +19.7‰), and PyIII (+25.3 to +32.3‰). Based on these results, and considering that the protoliths of the bauxites were likely Ni- and Co-rich black shales according to previous studies, a four-step model is proposed to explain the enrichment of Ni and Co in the bauxites: 1) during weathering and bauxite formation on the surface, Ni and Co were leached from the black shale together with sulfate; the metals were dissolved in the solution and partly adsorbed by Fe-oxides/hydroxides under moderate to high f O2 ; 2) during early diagenesis, the sulfate was partially reduced to sulfide via the bacterial sulfate reduction (BSR) process and formed PyI; much of the Ni and Co, together with sulfate, remained in the solution; 3) with increasing burial, temperature increased and f O2 decreased, and the remaining sulfate (with elevated δ34S V-CDT) was reduced to sulfide via the same BSR process and formed PyII; Ni was largely consumed and incorporated into PyIIa and PyIIb, whereas Co remained in the solution until precipitation of PyIIc; 4) by the time of PyIII precipitation, both Ni and Co had been taken by PyII, leaving a Ni- and Co-poor solution and PyIII. Step 1 occurred in a relatively open system, whereas steps 2–4 likely occurred in a closed system. [Display omitted] [ABSTRACT FROM AUTHOR]

• Single-dose dupilumab pharmacokinetics (PK) were studied in 30 Chinese subjects. • Repeated-dose PK were studied in 82 Chinese adults with atopic dermatitis. • PK were comparable to non-Asians after accounting for body weight. Dupilumab, a fully human monoclonal antibody targeting IL-4Rα, has demonstrated rapid and sustained improvements in clinical outcomes in patients with atopic dermatitis (AD), asthma, and chronic rhinosinusitis with nasal polyps. In a phase 1, double-blind, ascending-dose study, 30 healthy Chinese adults were randomized to single subcutaneous doses of dupilumab 200, 300, 600 mg, or placebo. In a phase 3, double-blind study, 165 Chinese adults with AD were randomized to dupilumab 300 mg or placebo every 2 weeks. Following single doses of dupilumab 200, 300, and 600 mg in the phase 1 study, mean serum maximum concentrations (C max) were 25.4 ± 4.0, 37.2 ± 14.5, and 77.3 ± 19.0 mg/L, respectively. For a 1.5-fold increase in dupilumab dose, 1.31-, 1.73-, and 1.66-fold increases in C max , area under the curve to real time (AUC last), and extrapolated to infinity (AUC) were observed, respectively, while a 2-fold dose increase resulted in 2.17-, 2.81-, and 2.80-fold increases, respectively. In the phase 3 study, mean dupilumab trough concentrations were 78.8 ± 32.0 and 86.4 ± 33.6 mg/L at weeks 12 and 16, respectively. C max increased approximately proportionally to dose, while AUC and AUC last increased greater than proportionally. Dupilumab pharmacokinetics were generally comparable between Chinese and non-Asian healthy subjects (single dose) and between Chinese and non-Asian AD patients (repeated doses), with differences accounted for by body weight. As differences in exposure by weight are unlikely to be clinically relevant based on late-stage study results, no dose adjustment by ethnic origin or weight is required. [ABSTRACT FROM AUTHOR]