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Three-stage niobium mineralization at Bayan Obo, China

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National Science Review 2024年第4期11卷 102-110页

作者： Yan Yu Yang li Yu liu Xiao-Xiao ling li-Guang Wu li Yang Lan Yang Bo Yang Yong-Gang Zhao Xian-hua li State Key Laboratory of lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences College of Earth and Planetary Science University of Chinese Academy of Sciences Ministry of Education Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking University Mining Research Institute Baotou Iron and Steel(Group) Co.LTD State Key Laboratory of Baiyunobo Rare Earth Resource Research and Comprehensive Utilization

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

关键词： niobium mineralization U-Pb dating ferrocolumbite Bayan Obo

Green manuring relocates microbiomes in driving the soil functionality of nitrogen cycling to obtain preferable grain yields in thirty years

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Science China(life Sciences) 2024年第3期67卷 596-610页

作者： Guopeng Zhou Kunkun Fan Songjuan Gao Danna Chang Guilong li Ting liang Hai liang shun li Jiudong Zhang Zongxian Che Weidong Cao State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China/Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural SciencesBeijing 100081China State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China College of Resources and Environmental Sciences Nanjing Agricultural UniversityNanjing 210095China Institute of Soil&Fertilizer and Resource&Environment Jiangxi Academy of Agricultural SciencesNanchang 330200China Institute of Soil and Fertilizer and Water-saving Agriculture Gansu Academy of Agricultural SciencesLanzhou 730070China

Fertilizers are widely used to produce more food, inevitably altering the diversity and composition of soil organisms. The role of soil biodiversity in controlling multiple ecosystem services remains unclear, especially after decades of fertilization. Here, we assess the contribution of the soil functionalities of carbon(C), nitrogen(N), and phosphorus(P) cycling to crop production and explore how soil organisms control these functionalities in a 33-year field fertilization experiment. The long-term application of green manure or cow manure produced wheat yields equivalent to those obtained with chemical N, with the former providing higher soil functions and allowing the functionality of N cycling(especially soil N mineralization and biological N fixation) to control wheat production. The keystone phylotypes within the global network rather than the overall microbial community dominated the soil multifunctionality and functionality of C,N, and P cycling across the soil profile(0–100 cm). We further confirmed that these keystone phylotypes consisted of many metabolic pathways of nutrient cycling and essential microbes involved in organic C mineralization, N_(2)O release, and biological N fixation. The chemical N, green manure, and cow manure resulted in the highest abundances of amoB, nifH, and GH48 genes and Nitrosomonadaceae,Azospirillaceae, and Sphingomonadaceae within the keystone phylotypes, and these microbes were significantly and positively correlated with N_(2)O release, N fixation, and organic C mineralization, respectively. Moreover, our results demonstrated that organic fertilization increased the effects of the network size and keystone phylotypes on the subsoil functions by facilitating the migration of soil microorganisms across the soil profiles and green manure with the highest migration rates. This study highlights the importance of the functionality of N cycling in controlling crop production and keystone phylotypes in regulating soil functions, and provides selectable fertilization strategies f

关键词： soil biodiversity soil multifunctionality element cycling keystone phylotypes

Laser manufacturing of spatial resolution approaching quantum limit

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light(Science & Applications) 2024年第3期13卷 421-428页

作者： Xiao-Jie Wang Hong-hua Fang Zhen-Ze li Dan Wang Hong-Bo Sun State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentTsinghua UniversityBeijing 100084China State Key Laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin University2699 Qianjin StreetChangchun 130012China

Atomic and close-to-atom scale manufacturing is a promising avenue toward single-photon emitters,single-electron transistors,single-atom memory,and quantum-bit devices for future communication,computation,and sensing applications.Laser manufacturing is outstanding to this end for ease of beam manipulation,batch production,and no requirement for photomasks.It is,however,suffering from optical diffraction limits.Herein,we report a spatial resolution improved to the quantum limit by exploiting a threshold tracing and lock-in method,whereby the two-order gap between atomic point defect complexes and optical diffraction limit is surpassed,and a feature size oflized.The underlying physics is that the uncertainty of local atom thermal motion dominates electron excitation,rather than the power density slope of the incident laser.We show that the colour centre yield in hexagonal boron nitride is transformed from stochastic to deterministic,and the emission from individual sites becomes polychromatic to monochromatic.As a result,single colour centres in the regular array are deterministically created with a unity yield and high positional accuracy,serving as a step forward for integrated quantum technological applications.

关键词： quantum limit resolution

Comparative transcriptomic analysis reveals the molecular changes of acute pancreatitis in experimental models

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World Journal of Gastroenterology 2024年第14期30卷 2038-2058页

作者： Pan Zheng Xue-Yang li Xiao-Yu Yang huan Wang ling Ding Cong He Jian-hua Wan hua-Jing Ke Nong-hua Lu Nian-Shuang li Yin Zhu Department of Gastroenterology Digestive Disease HospitalThe First Affiliated HospitalJiangxi Medical CollegeNanchang UniversityNanchang 330006Jiangxi ProvinceChina

BACKGROUND Acute pancreatitis(AP)encompasses a spectrum of pancreatic inflammatory conditions,ranging from mild inflammation to severe pancreatic necrosis and multisystem organ failure.Given the challenges associated with obtaining human pancreatic samples,research on AP predominantly relies on animal models.In this study,we aimed to elucidate the fundamental molecular mechanisms underlying AP using various AP models.AIM To investigate the shared molecular changes underlying the development of AP across varying severity levels.METHODS AP was induced in animal models through treatment with caerulein alone or in combination with lipopolysaccharide(LPS).Additionally,using Ptf1αto drive the specific expression of the hM3 promoter in pancreatic acinar cells transgenic C57BL/6J-hM3/Ptf1α(cre)mice were administered Clozapine N-oxide to induce AP.Subsequently,we conducted RNA sequencing of pancreatic tissues and validated the expression of significantly different genes using the Gene Expression Omnibus(GEO)database.RESULTS Caerulein-induced AP showed severe inflammation and edema,which were exacerbated when combined with LPS and accompanied by partial pancreatic tissue necrosis.Compared with the control group,RNA sequencing analysis revealed 880 significantly differentially expressed genes in the caerulein model and 885 in the caerulein combined with the LPS model.Kyoto Encyclopedia of Genes and Genomes enrichment analysis and Gene Set Enrichment Analysis indicated substantial enrichment of the TLR and NOD-like receptor signaling pathway,TLR signaling pathway,and NF-κB signaling pathway,alongside elevated levels of apoptosis-related pathways,such as apoptosis,P53 pathway,and phagosome pathway.The significantly elevated genes in the TLR and NOD-like receptor signaling pathways,as well as in the apoptosis pathway,were validated through quantitative real-time PCR experiments in animal models.Validation from the GEO database revealed that only MYD88 concurred in both mouse pancreatic tissue and human AP peripheral blood,whil

关键词： Acute pancreatitis RNA-sequencing Experimental acute pancreatitis models Inflammatory Apoptosis TLR and NOD-like signaling pathways

All types of base conversions allowed by base editors

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Science China(life Sciences) 2024年第2期67卷 431-433页

作者： shun-Qing liang Wen Xue RNA Therapeutics Institute UMass Chan Medical SchoolWorcester 01655USA Department of Molecular Cell and Cancer BiologyUMass Chan Medical SchoolWorcester 01655USA Department of Molecular Medicine UMass Chan Medical SchoolWorcester 01655USA li Weibo Institute for Rare Diseases Research UMass Chan Medical SchoolWorcester 01655USA

Base editors(BEs) hold great promise as tools for introducing single-base-pair changes in both basic research and therapeutic applications(Rees and liu,2018).Base editors are composed of a Cas9 nickase fused to a DNA-modifying enzyme,which chemically modifies nucleobases within a specific targeting window near the Cas9-binding site.

关键词： base bases allowed

One-step hydrothermal synthesis of few-layered metallic phase MoS2 for high-performance supercapacitors

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Progress in Natural Science:Materials International 2024年第2期34卷 429-436页

作者： Jing Xu Xulong Yuan Yujie Zhao Shaoqi Rui Qingling Jia Han li shun Lu Bing li Yongxing Zhang Xuebin Zhu Anhui Province Key Laboratory of Pollutant Sensitive Materials and Environmental Remediation Anhui Province Key Laboratory of Intelligent Computing and Applications Anhui Province Industrial Generic Technology Research Center for Alumics Materials Huaibei Normal University Chongqing Institute of Green and Intelligent Technology Chinese Academy of Sciences Key Laboratory of Materials Physics Institute of Solid State Physics HFIPS Chinese Academy of Sciences

In recent years,molybdenum disulfide（MoS2） has gained significant attention in the scientific community.Fewlayered MoS2demonstrates unique properties and potential applications.However,the synthesis of few-layered and high-purity 1T-MoS2is still a challenge.In this study,we successfully employed a hydrothermal method to synthesize few-layered and high-purity 1T-MoS2.The purity of the material is controlled by a combination of sodium borohydride and ethanol.Notably,the few-layered 1T-MoS2exhibits exceptional performance as a supercapacitor,including the high specific capacitance(250.3 F g-1at a current density of 1 A g-1) and excellent long-trem cycling stability（90.7 % after 5000 cycles）.Meanwhile,the asymmetric device assembled by 6-FL-1TMoS2and active carbon on carbon cloths exhibits excellent flexibility and high energy and power density(23.1μWh cm-2at 600 μW cm-2,55 μWh cm-2at 12000 μW cm-2).This work provides valuable insights into the synthesis of few-layered and high-purity 1T-MoS2,opening up new avenues for further research and applications.

关键词： 1T-MoS2 Few-layered High-purity One-pot hydrothermal method Supercapacitor

The effect of Ti and Zr content on the structure,mechanics and energy-release characteristics of Ti—Zr—Ta alloys

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Defence Technology（防务技术） 2024年第1期31卷 343-350页

作者： Jia-yu Meng Jing-zhi He Bin Zhang Jin Chen shun li Dun Niu Yu Tang Xi’an Modern Chemistry Research Institute Xi'an710065China College of Aerospace Science and Engineering National University of Defense TechnologyChangsha410073China

Energetic structural materials(ESMs)are a new type of structural materials with bearing and damage characteristics.In this work the microstructure,mechanical properties and energy release characteristics of multi-element Ti-Zr-Ta alloys with good casting performance were studied.The microstructure of the Ti_(x)ZrTa alloys gradually change from BCC+HCP to single BCC structure with the increase of Ti.While the Ti_(2)Zr_(y)Ta alloys was still uniform and single BCC structure with the increase of Zr.The evolution of microstructure and composition then greatly affect the mechanical properties and energy-release characteristics of Ti-Zr-Ta alloys.The synergistic effect of dual phase structure increases the fracture strain of Ti_(x)ZrTa(x=0.2,0.5)with the Ti content decreases,while the fracture strain of Ti_(x)ZrTa(x=2.0,3.0,4.0)gradually increase with the Ti content increases caused by the annihilation of the obstacles for dislocation movement.And as Zr content increases,the fracture strain of Ti_(2)Zr_(y)Ta alloys decrease,then the oxidation reaction rate and fragmentation degree gradually increase.The higher oxidation rate and the lager exposed oxidation area jointly leads the higher releasing energy efficiency of Ti_(x)ZrTa alloys with low Ti content and Ti_(2)Zr_(y)Ta alloys with high Zr content.

关键词： Energetic structural materials Ti-Zr-Ta Multi-element alloy Energy release characteristics

Comparison of different preoperative objective nutritional indices for evaluating 30-d mortality and complications after liver transplantation

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World Journal of Gastrointestinal Surgery 2024年第1期16卷 143-154页

作者： Chuan li Hong-Xia Chen Yan-hua Lai Department of Transplantation People’s Hospital of Guangxi Zhuang Autonomous RegionNanning 530021Guangxi Zhuang Autonomous RegionChina Department of Clinical Pharmacy People’s Hospital of Guangxi Zhuang Autonomous RegionNanning 530021Guangxi Zhuang Autonomous RegionChina

BACKGROUND The nutritional status is closely related to the prognosis of liver transplant re-cipients,but few studies have reported the role of preoperative objective nutri-tional indices in predicting liver transplant outcomes.AIM To compare the predictive value of various preoperative objective nutritional indicators for determining 30-d mortality and complications following liver transplantation(LT).METHODS A retrospective analysis was conducted on 162 recipients who underwent LT at our institution from December 2019 to June 2022.RESULTS This study identified several independent risk factors associated with 30-d mor-tality,including blood loss,the prognostic nutritional index(PNI),the nutritional risk index(NRI),and the control nutritional status.The 30-d mortality rate was 8.6%.Blood loss,the NRI,and the PNI were found to be independent risk factors for the occurrence of severe postoperative complications.The NRI achieved the highest prediction values for 30-d mortality[area under the curve(AUC)=0.861,Plications(AUC=0.643,P=0.011).Compared to those in the high NRI group,the low patients in the NRI group had lower preoperative body mass index and prealbumin and albumin levels,as well as higher alanine aminotransferase and total bilirubin levels,Model for End-stage liver Disease scores and prothrombin time(Plity.CONCLUSION The NRI has good predictive value for 30-d mortality and severe complications following LT.The NRI could be an effective tool for transplant surgeons to evaluate perioperative nutritional risk and develop relevant nutritional therapy.

关键词： liver transplantation Nutritional indicator Complications Prognosis Nutrition assessment

Artificial selection shapes the lower genomic diversity and higher selective pressures on the sex chromosomes of domestic animals

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Science China(life Sciences) 2024年第5期67卷 1072-1075页

作者： Meiming Wu Dongfeng Wang Meng-hua li Fenghua Lv College of Animal Science and Technology China Agricultural UniversityBeijing 100193China CAS Key Laboratory of Animal Ecology and Conservation Biology Institute of ZoologyChinese Academy of Science(CAS)Beijing 100101China College of life Sciences University of Chinese Academy of SciencesBeijing 100049China Sanya Institute of China Agricultural University Sanya 572024China

Dear Editor,Sheep and goats were among the earliest domestic animals(Zeder,2008).During the transition from being hunted to being herded,excess males not involved in propagation were slaughtered at young ages under th... 详细信息

关键词： earliest harvest young