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Spin effect on redox acceleration and regioselectivity in Fe-catalyzed alkyne hydrosilylation

National Science Review 2024年第2期11卷 155-167页

作者： Peng He Meng-Yang Hu Jin-Hong Li Tian-Zhang qiao Yi-lin lu Shou-Fei Zhu Frontiers Science Center for New Organic Matter State Key Laboratory and Institute of Elemento-Organic Chemistry Nankai University

Iron catalysts are ideal transition metal catalysts because of the Earths abundant, cheap, biocompatible features of iron salts. Iron catalysts often have unique open-shell structures that easily undergo spin crossover in chemical transformations, a feature rarely found in noble metal catalysts. Unfortunately, little is known currently about how the open-shell structure and spin crossover affect the reactivity and selectivity of iron catalysts, which makes the development of iron catalysts a low efficient trial-and-error program. In this paper, a combination of experiments and theoretical calculations revealed that the iron-catalyzed hydrosilylation of alkynes is typical spin-crossover catalysis. Deep insight into the electronic structures of a set of well-defined open-shell active formal Fe(0) catalysts revealed that the spin-delocalization between the iron center and the 1,10-phenanthroline ligand effectively regulates the iron center's spin and oxidation state to meet the opposite electrostatic requirements of oxidative addition and reductive elimination, respectively,and the spin crossover is essential for this electron transfer process. The triplet transition state was essential for achieving high regioselectivity through tuning the nonbonding interactions. These findings provide an important reference for understanding the effect of catalyst spin state on reaction. It is inspiring for the development of iron catalysts and other Earth-abundant metal catalysts, especially from the point of view of ligand development.

关键词： spin effect spin-delocalization spin crossover iron-catalysis alkyne hydrosilylation

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NFXL1 functions as a transcriptional activator required for thermotolerance at reproductive stage in Arabidopsis

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Journal of Integrative Plant Biology 2024年第1期66卷 54-65页

作者： qiao‐Yun Zhu lin‐lin Zhang Jian‐Xiang Liu State Key Laboratory of Plant Environmental Resilience College of Life SciencesZhejiang UniversityHangzhou 310027China

Plants are highly susceptible to abiotic stresses,particularly heat stress during the reproductive stage.However,the specific molecular mechanisms underlying this sensitivity remain largely unknown.In the current study,we demonstrate that the Nuclear Transcription Factor,X-box Binding Protein 1-Like 1(NFXL1),directly regulates the expression of DEHYDRATION-RESPONSIVE ELEMENT-BINDING PROTEIN 2A(DREB2A),which is crucial for reproductive thermotolerance in Arabidopsis.NFXL1 is upregulated by heat stress,and its mutation leads to a reduction in silique length(seed number)under heat stress conditions.RNA-Seq analysis reveals that NFXL1 has a global impact on the expression of heat stress responsive genes,including DREB2A,Heat Shock Factor A3(HSFA3)and Heat Shock Protein 17.6(HSP17.6)in flower buds.Interestingly,NFXL1 is enriched in the promoter region of DREB2A,but not of either HSFA3 or HSP17.6.Further experiments using electrophoretic mobility shift assay have confirmed that NFXL1 directly binds to the DNA fragment derived from the DREB2A promoter.Moreover,effector-reporter assays have shown that NFXL1 activates the DREB2A promoter.The DREB2A mutants are also heat stress sensitive at the reproductive stage,and DEREB2A is epistatic to NFXL1 in regulating thermotolerance in flower buds.It is known that HSFA3,a direct target of DREB2A,regulates the expression of heat shock proteins genes under heat stress conditions.Thus,our findings establish NFXL1 as a critical upstream regulator of DREB2A in the transcriptional cassette responsible for heat stress responses required for reproductive thermotolerance in Arabidopsis.

关键词： Arabidopsis DREB2A heat stress NFXL1 reproductive thermotolerance

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Comprehensive study on the spatial distribution of heavy metals and their environmental risks in high-sulfur coal gangue dumps in China

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Journal of Environmental Sciences 2024年第2期136卷 486-497页

作者： Yingbo Dong Huan lu Hai lin School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory on Resource-oriented Treatment of Industrial Pollutants Beijing 100083China

The accumulation of coal gangue(CG)from coal mining is an important source of heavy metals(HMs)in soil.Its spatial distribution and environment risk assessment are extremely important for the management and remediation of HMs.Eighty soil samples were collected from the high-sulfur CG site in northern China and analyzed for six HMs.The results showed that the soil was heavily contaminated by Mn,Cr and Ni based on the Nemerow index,and posed seriously ecological risk depended on the geo-accumulation index,potential ecological risk index and risk assessment code.The semi-variogram model and ordinary kriging interpolation accurately portrayed the spatial distribution of HMs.Fe,Mn,and Cr were distributed by band diffusion,Ni was distributed by core,the distribution of Cu had obvious patchiness and Zn was more uniform.The spatial autocorrelation indicated that all HMs had strong spatial heterogeneity.The BCR sequential extraction was employed to qualify the geochemical fractions of HMs.The data indicated that Fe and Cr were dominated by residual fraction;Cu,Ni and Zn were dominated by reducible and oxidizable fractions;Mn was dominated by reducible and acid-extractable(25.38%-44.67%)fractions.Pearson correlation analysis showed that pH was the main control factor affecting the non-residue fractions of HMs.Therefore,acid production from high sulfur CG reduced soil pH by 2-3,which indirectly promoted the activity of HMs.Finally,the conceptual model of HMs contamination at the CG site was proposed,which can be useful for the development of ecological remediation strategies.

关键词： High-sulfur coal gangue Soil contamination Heavy metals Spatial distribution Geochemical fractions Risk assessment

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Staying hungry:a roadmap to harnessing central regulators of symbiotic nitrogen fixation under fluctuating nitrogen availability

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aBIOTECH 2024年第1期5卷 107-113页

作者： Lijin qiao Jieshun lin Takuya Suzaki Pengbo Liang State Key Laboratory of Plant Environmental Resilience College of Biological SciencesChina Agricultural UniversityBeijingChina MOA Key Laboratory of Soil Microbiology Rhizobium Research CenterChina Agricultural UniversityBeijingChina Department of Molecular Biology and Genetics Aarhus UniversityAarhusDenmark Faculty of Life and Environmental Sciences University of TsukubaTsukubaIbarakiJapan Tsukuba Plant-Innovation Research Center University of TsukubaTsukubaIbarakiJapan

Legumes have evolved specific inventions to enhance nitrogen(N)acquisition by establishing symbiotic interactions with N-fixing rhizobial bacteria.Because symbiotic N fixation is energetically costly,legumes have developed sophisticated mechanisms to ensure carbon-nitrogen balance,in a variable environment,both locally and at the whole plant level,by monitoring nodule number,nodule development,and nodular nitrogenase activity,as well as controlling nodule senescence.Studies of the autoregulation of nodulation and regulation of nodulation by nodule inception(NIN)and NIN-LIKE PROTEINs(NLPs)have provided great insights into the genetic mechanisms underlying the nitrateinduced regulation of root nodulation for adapting to N availability in the rhizosphere.However,many aspects of N-induced pleiotropic regulation remain to be fully explained,such as N-triggered senescence in mature nodules.Wang et al.determined that this process is governed by a transcriptional network regulated by NAC-type transcription factors.Characterization and dissection of these soybean nitrogenassociated NAPs(SNAPs)transcription factor-mastered networks have yielded a roadmap for exploring how legumes rewire nodule functions across a range of N levels,laying the foundation for enhancing the growth of N-deprived crops in agricultural settings.

关键词： Symbiotic nitrogen fixation N-adapted nodulation Nodule senescence NIN NLPs SNAPs

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Immune checkpoint inhibitor-associated gastritis:Patterns and management

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World Journal of Gastroenterology 2024年第14期30卷 1941-1948页

作者： Jing lin Zhong-qiao lin Shi-Cheng Zheng Yu Chen Department of Medical Oncology Clinical Oncology School of Fujian Medical UniversityFujian Cancer HospitalFuzhou 350000Fujian ProvinceChina Phase I Clinical Trial Ward Clinical Oncology School of Fujian Medical UniversityFujian Cancer HospitalFuzhou 350000Fujian ProvinceChina School of Basic Medical Sciences Fujian Medical UniversityFuzhou 350000Fujian ProvinceChina

Immune checkpoint inhibitors(ICIs)are widely used due to their effectiveness in treating various tumors.Immune-related adverse events(irAEs)are defined as adverse effects resulting from ICI treatment.Gastrointestinal irAEs are a common type of irAEs characterized by intestinal side effects,such as diarrhea and colitis,which may lead to the cessation of ICIs.Although irAE gastritis is rarely reported,it may lead to serious complications such as gastrorrhagia.Furthermore,irAE gastritis is often difficult to identify early due to its diverse symptoms.Although steroid hormones and immunosuppressants are commonly used to reverse irAEs,the best regimen and dosage for irAE gastritis remains uncertain.In addition,the risk of recurrence of irAE gastritis after the reuse of ICIs should be considered.In this editorial,strategies such as early identification,pathological diagnosis,mana-gement interventions,and immunotherapy rechallenge are discussed to enable clinicians to better manage irAE gastritis and improve the prognosis of these patients.

关键词： Immunotherapy Immune checkpoint inhibitor Immune-related adverse events Immune checkpoint inhibitor-related gastritis

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Long non-coding RNAs with essential roles in neurodegenerative disorders

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Neural Regeneration Research 2024年第6期19卷 1212-1220页

作者： Wandi Xiong lin lu Jiali Li Key Laboratory of Animal Models and Human Disease Mechanisms of Chinese Academy of Sciences & Yunnan Province Kunming Institute of Zoology the Chinese Academy of Sciences Tsinghua-Peking Center for Life Sciences National Institute on Drug Dependence Peking University PKU/McGovern Institute for Brain Research Peking University Institute of Mental Health National Clinical Research Center for Mental Disorders Key Laboratory of Mental Health and Peking University Sixth Hospital Peking University

Recently, with the advent of high-resolution and high-throughput sequencing technologies, an increasing number of long non-coding RNAs(lncRNAs) have been found to be involved in the regulation of neuronal function in the central nervous system with specific spatiotemporal patterns, across different neurodegenerative diseases. However, the underlying mechanisms of lncRNAs during neurodegeneration remain poorly understood. This review provides an overview of the current knowledge of the biology of lncRNAs and focuses on introducing the latest identified roles, regulatory mechanisms, and research status of lncRNAs in Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, and amyotrophic lateral sclerosis. Finally, this review discusses the potential values of lncRNAs as diagnostic biomarkers and therapeutic targets for neurodegenerative diseases, hoping to provide broader implications for developing effective treatments.

关键词： Alzheimer’s disease amyotrophic lateral sclerosis biomarker Huntington’s disease long non-coding RNAs neurodegenerative diseases Parkinson’s disease therapy transcriptional regulation translational regulation

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Microwave-induced thermoacoustic elastic imaging:A simulation study

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Journal of Innovative Optical Health Sciences 2024年第2期17卷 1-11页

作者： lin Huang Zheng Liang Shuaiqi qiao Weipeng Wang School of Electronic Science and Engineering(National Exemplary School of Microelectronics)University of Electronic Science and Technology of China ChengduP.R.China Zhangjiang Laboratory 100 Haike Road Shanghai 201204P.R.China

Microwave-induced thermoacoustic imaging(MTI)has the advantages of high resolution,high contrast,non-ionization,and non-invasive.Recently,MTI was used in the¯eld of breast cancer screening.In this paper,based on the¯nite element method(FEM)and COMSOL Multiphysics software,a three-dimensional breast cancer model suitable for exploring the MTI process is proposed to investigate the in°uence of Young's modulus(YM)of breast cancer tissue on MTI.It is found that the process of electromagnetic heating and initial pressure generation of the entire breast tissue is earlier in time than the thermal expansion process.Besides,compared with normal breast tissue,tumor tissue has a greater temperature rise,displacement,and pressure rise.In particular,YM of the tumor is related to the speed of thermal expansion.In particular,the larger the YM of the tumor is,the higher the heating and contraction frequency is,and the greater the maximum pressure is.Di®erent Young's moduli correspond to di®erent thermoacoustic signal spectra.In MTI,this study can be used to judge di®erent degrees of breast cancer based on elastic imaging.In addition,this study is helpful in exploring the possibility of microwave-induced thermoacoustic elastic imaging(MTAE).

关键词： Thermoacoustic imaging breast cancer multi-physics simulation elastic imaging

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Degradation of iopamidol in the permanganate/sulfite process:Evolution of iodine species and effect on the subsequent formation of disinfection by-products

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Journal of Environmental Sciences 2024年第1期135卷 345-352页

作者： Yimin lin Hongyu Dong Yating Zhu Gongming Zhou Junlian qiao Xiaohong Guan State Key Laboratory of Pollution Control and Resources Reuse College of Environmental Science and EngineeringTongji UniversityShanghai 200092China Department of Environmental Science School of Ecological and Environmental SciencesEast China Normal UniversityShanghai 200241China

Permanganate/sulfite(Mn(VII)/S(IV))process is a promising pre-oxidation technology for sequestering the emerging organic contaminants in drinking water treatment plant.Iopamidol(IPM),a representative of iodinated X-ray contrast media,has been widely detected in water sources and has the risk of forming iodinated disinfection byproducts(I-DBPs)in water treatment system.In this study,we investigated the evolution of iodine species during the IPM degradation by the Mn(VII)/S(IV)process and its effect on the subsequent formation of I-DBPs during chlorination at pH 7.0 and 8.0.IPM could be effectively degraded in the Mn(VII)/S(IV)process at environmentally relevant pH(pH 7.0 and 8.0).The results of quenching and competitive oxidation kinetic experiments revealed that SO^(·-)_(4)was the major reactive oxidizing species contributing to the degradation of IPM whereas the contributions of HO·and reactive manganese species were negligible in the Mn(VII)/S(IV)process.I–and IO–3were generated while no HOI was detected during the degradation of IPM in the Mn(VII)/S(IV)process.The effects of IPM oxidation by Mn(VII)/S(IV)on the subsequent formation of chlorinated disinfection by-products(Cl-DBPs)during chlorination were related to the category of Cl-DBPs.The pre-oxidation of IPM by Mn(VII)/S(IV)resulted in the generation of I-DBPs during the disinfection process although no I-DBPs were detected if no pre-oxidation was applied.The finding of this study suggested that attention should be paid to the toxicity of DBPs when water containing iodinated organic contaminants is treated by Mn(VII)/S(IV)process or other pre-oxidation technologies.

关键词： Permanganate/sulfite Iopamidol Sulfate radical Iodinated disinfection byproducts Pre-oxidation

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Graphene binding on black phosphorus enables high on/off ratios and mobility

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National Science Review 2024年第2期11卷 188-195页

作者： Fanrong lin Zhonghan Cao Feiping Xiao Jiawei Liu Jiabin qiao Minmin Xue Zhili Hu Ying Liu Huan lu Zhuhua Zhang Jens Martin Qingjun Tong Wanlin Guo Yanpeng Liu Key Laboratory for Intelligent Nano Materials and Devices of Ministry of Education State Key Laboratory of Mechanics and Control of Mechanical Structures and Institute for Frontier Science Nanjing University of Aeronautics and Astronautics Centre for Advanced 2D Materials National University of Singapore School of Physics and Electronics Hunan University Centre for Quantum Physics Key Laboratory of Advanced Optoelectronic Quantum Architecture and MeasurementSchool of PhysicsBeijing Institute of Technology Leibniz Institute für Kristallzüchtung

Graphene is one of the most promising candidates for integrated circuits due to its robustness against short-channel effects, inherent high carrier mobility and desired gapless nature for Ohmic contact, but it is difficult to achieve satisfactory on/off ratios even at the expense of its carrier mobility, limiting its device applications. Here, we present a strategy to realize high back-gate switching ratios in a graphene monolayer with well-maintained high mobility by forming a vertical heterostructure with a black phosphorus multi-layer. By local current annealing, strain is introduced within an established area of the graphene, which forms a reflective interface with the rest of the strain-free area and thus generates a robust off-state via local current depletion. Applying a positive back-gate voltage to the heterostructure can keep the black phosphorus insulating, while a negative back-gate voltage changes the black phosphorus to be conductive because of hole accumulation. Then, a parallel channel is activated within the strain-free graphene area by edge-contacted electrodes, thereby largely inheriting the intrinsic carrier mobility of graphene in the on-state. As a result, the device can provide an on/off voltage ratio of >10～3 as well as a mobility of ～8000 cm2V-1s-1at room temperature, meeting the low-power criterion suggested by the International Roadmap for Devices and Systems.

关键词： graphene on/offratio mobility black phosphorus reflective interface

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Ubiquitin-specific protease 21 promotes tumorigenicity and stemness of colorectal cancer by deubiquitinating and stabilizing ZEB1

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 1006-1018页

作者： Jun-Jun lin Ye-Cai lu Department of Gastrointestinal Surgery Chaohu Hospital of Anhui Medical UniversityChaohu 238000Anhui ProvinceChina

BACKGROUND Colorectal cancer(CRC)is one very usual tumor together with higher death rate.Ubiquitin-specific protease 21(USP21)has been confirmed to take part into the regulation of CRC progression through serving as a facilitator.Interestingly,the promotive function of USP21 has also discovered in the progression of CRC.ZEB1 has illustrated to be modulated by USP7,USP22 and USP51 in cancers.However,the regulatory functions of USP21 on ZEB1 in CRC progression need more invest-igations.AIM To investigate the relationship between USP21 and ZEB1 in CRC progression.METHODS The mRNA and protein expressions were assessed through RT-qPCR,western blot and IHC assay.The interaction between USP21 and ZEB1 was evaluated through Co-IP and GST pull down assays.The cell proliferation was detected through colony formation assay.The cell migration and invasion abilities were determined through Transwell assay.The stemness was tested through sphere formation assay.The tumor growth was evaluated through in vivo mice assay.RESULTS In this work,USP21 and ZEB1 exhibited higher expression in CRC,and resulted into poor prognosis.Moreover,the interaction between USP21 and ZEB1 was further investigated.It was demonstrated that USP21 contributed to the stability of ZEB1 through modulating ubiquitination level.In addition,USP21 streng-thened cell proliferation,migration and stemness through regulating ZEB1.At last,through in vivo assays,it was illustrated that USP21/ZEB1 axis aggravated tumor growth.CONCluSION For the first time,these above findings manifested that USP21 promoted tumorigenicity and stemness of CRC by deubiquitinating and stabilizing ZEB1.This discovery suggested that USP21/ZEB1 axis may provide novel sights for the treatment of CRC.

关键词： Ubiquitin-specific protease 21 ZEB1 Stemness Colorectal cancer

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