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New strategies for asymmetric photocatalysis: asymmetric organocatalytic/photoredox relay catalysis for efficient synthesis of polycyclic compounds containing vicinal amino alcohols

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Science China Chemistry 2024年第3期67卷 945-952页

作者： Jia-Lu Zhang Wen-Bo he xiu-Qin Hu Peng-Fei Xu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China State Key Laboratory of Veterinary Etiological Biology College of Veterinary MedicineLanzhou UniversityLanzhou Veterinary Research InstituteChinese Academy of Agricultural SciencesLanzhou 730000China MOE Frontiers Science Center for Rare Isotopes Lanzhou UniversityLanzhou 730000China

An asymmetric catalytic strategy in photocatalysis utilizing a chirality-induced approach through an organocatalytic/photoredox relay catalysis strategy is successfully achieved for the rapid construction of polycyclic compounds containing vicinal amino alcohols in a one-pot protocol. This methodology facilitates the efficient synthesis of diverse substituted polycyclic tetrahydroquinoline and benzofuran-derived vicinal amino alcohols, each containing five consecutive chiral centers, with high yields,excellent diastereoselectivities and enantioselectivities(up to 95% yield, >20:1 dr and 98% ee), under mild reaction conditions driven by sequential bifunctional squaramide organocatalyst-catalyzed [4+2] annulation and photocatalyst-catalyzed ketyl radical addition cyclization reaction process. Furthermore, investigations into the stereoselectivity mechanism and high-resolution mass spectrometry(HRMS) experiments on free radical trapping have provided evidence for elucidating the detailed mechanism of chirality-induced processes and chiral intermediate conversions in this procedure.

关键词： enantioselective photocatalysis asymmetric organocatalytic/photocatalysis relay catalysis five consecutive chiral centers chirality-induced strategy chirality vicinal amino alcohols

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Circulating proteomic biomarkers for diagnosing sporadic amyotrophic lateral sclerosis:a cross-sectional study

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Neural Regeneration Research 2024年第8期19卷 1842-1848页

作者： Lu he Qinming Zhou Chaoyang xiu Yaping Shao Dingding Shen Huanyu Meng Weidong Le Sheng Chen Department of Neurology and Institute of Neurology Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghaiChina Department of Neurology Hospital of Chengdu University of Traditional Chinese MedicineChengduSichuan ProvinceChina Center for Translational Research on Neurological Diseases the First Affiliated HospitalDalian Medical UniversityDalianLiaoning ProvinceChina Co-innovation Center of Neuroregeneration Nantong UniversityNantongJiangsu ProvinceChina Institute of Neurology Sichuan Academy of Medical Sciences-Sichuan Provincial HospitalChengduSichuan ProvinceChina Department of Neurology Xinrui HospitalWuxiJiangsu ProvinceChina

Biomarke rs are required for the early detection,prognosis prediction,and monitoring of amyotrophic lateral sclerosis,a progressive disease.Proteomics is an unbiased and quantitative method that can be used to detect neurochemical signatures to aid in the identification of candidate biomarke rs.In this study,we used a label-free quantitative proteomics approach to screen for substantially differentially regulated proteins in ten patients with sporadic amyotrophic lateral scle rosis compared with five healthy controls.Su bstantial upregulation of serum proteins related to multiple functional clusters was observed in patients with spo radic amyotrophic lateral sclerosis.Potential biomarke rs were selected based on functionality and expression specificity.To validate the proteomics profiles,blood samples from an additional cohort comprising 100 patients with sporadic amyotrophic lateral sclerosis and 100 healthy controls were subjected to enzyme-linked immunosorbent assay.Eight substantially upregulated serum proteins in patients with spora dic amyotrophic lateral sclerosis were selected,of which the cathelicidin-related antimicrobial peptide demonstrated the best discriminative ability between patients with sporadic amyotrophic lateral sclerosis and healthy controls(area under the curve[AUC]=0.713,Pher enhance diagnostic accuracy,a multi-protein combined discriminant algorithm was developed incorporating five proteins(hemoglobin beta,cathelicidin-related antimicrobial peptide,talin-1,zyxin,and translationally-controlled tumor protein).The algo rithm achieved an AUC of 0.811 and a P-value ofhe diagnosis of sporadic amyotrophic lateral scle rosis.Subsequently,the ability of candidate biomarkers to discriminate between early-stage amyotrophic lateral sclerosis patients and controls,as well as patients with different disease severities,was examined.A two-protein panel comprising talin-1 and translationally-controlled tumor protein effectively d

关键词： amyotrophic lateral sclerosis cathelicidin-related antimicrobial peptide hemoglobin label-free quantitative proteomics multi-protein combined diagnostic panel serum biomarkers talin-1 translationally-controlled tumor protein zyxin

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Tunable VO_(2) cavity enables multispectral manipulation from visible to microwave frequencies

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Light(Science & Applications) 2024年第3期13卷 510-518页

作者： Hang Wei Jinxin Gu Tao Zhao Zhiyuan Yan he-xiu Xu Shuliang Dou Cheng-Wei Qiu Yao Li Center for Composite Materials and Structure Harbin Institute of TechnologyHarbin 150001China National University of Singapore Department of Electrical&Computer EngineeringSingapore 117583Singapore School of Chemical Engineering and Technology Harbin Institute of TechnologyHarbin 150001China Suzhou Laboratory Suzhou 215123China

Optical materials capable of dynamically manipulating electromagnetic waves are an emerging field in memories,optical modulators,and thermal management.Recently,their multispectral design preliminarily attracts much attention,aiming to enhance their efficiency and integration of functionalities.However,the multispectral manipulation based on these materials is challenging due to their ubiquitous wavelength dependence restricting their capacity to narrow wavelengths.In this article,we cascade multiple tunable optical cavities with selective-transparent layers,enabling a universal approach to overcoming wavelength dependence and establishing a multispectral platform with highly integrated functions.Based on it,we demonstrate the multispectral(ranging from 400 nm to 3 cm),fast response speed(0.9 s),and reversible manipulation based on a typical phase change material,vanadium dioxide.Our platform involves tandem VO_(2)-based Fabry–Pérot(F-P)cavities enabling the customization of optical responses at target bands independently.It can achieve broadband color-changing capacity in the visible region(a shift of~60 nm in resonant wavelength)and is capable of freely switching between three typical optical models(transmittance,reflectance,and absorptance)in the infrared to microwave regions with drastic amplitude tunability exceeding 0.7.This work represents a state-of-art advance in multispectral optics and material science,providing a critical approach for expanding the multispectral manipulation ability of optical systems.

关键词： spectral microwave visible

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Oxidation behavior of 4774DD1 Ni-based single-crystal superalloy at 980℃ in air

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China Foundry 2024年第2期21卷 116-124页

作者： Yu Fang Ya-zhou Li Qiang Yang Qun-gong he xiu-fang Gong Qian Duan Hai-yang Song Fu Wang Qiong-yuan Zhang Hong Zeng State Key Laboratory of Long-Life High Temperature Materials Dongfang Turbine Co.Ltd.Deyang 618000SichuanChina State Key Laboratory for Manufacturing System Engineering School of Mechanical EngineeringXi’an Jiaotong UniversityXi’an 710049China

The oxidation behavior of a novel Ni-based single-crystal 4774DD1 superalloy for industrial gas turbine applications was investigated by the isothermal oxidation at 980℃ and discontinuous oxidation weight gain methods.The phase constitution and morphology of surface oxides and the characteristics of the crosssection oxide film were analyzed by XRD,SEM and EDS.Results show that the oxidation kinetics of the 4774DD1 superalloy follows the cubic law,indicating its weak oxidation resistance at this temperature.As the oxidation time increases,the composition of the oxide film evolves as following:One layer consisting of a bottom Al_(2)O_(3)sublayer and an upper(Al_(2)O_(3)+NiO)mixture sublayer after oxidized for 25 h.Then,two layers composed of an outermost small NiO discontinuous grain layer and an internal layer for 75 h.This internal layer is consisted of the bottom Al_(2)O_(3)sublayer,an intermediate narrow CrTaO_(4)sublayer,and an upper(Al_(2)O_(3)+NiO)mixture sublayer.Also two layers comprising an outermost relative continuous NiO layer with large grain size and an internal layer as the oxidation time increases to 125 h.This internal layer is composed of the upper(Al_(2)O_(3)+NiO)mixture sublayer,an intermediate continuous(CrTaO_(4)+NiWO_(4))mixture sublayer,and a bottom Al_(2)O_(3)sublayer.Finally,three layers consisting of an outermost(NiAl2O_(4)+NiCr2O_(4))mixture layer,an intermediate(CrTaO_(4)+NiWO_(4))mixture layer,and a bottom Al_(2)O_(3)layer for 200 h.

关键词： nickel-base single crystal superalloy oxidation kinetics oxide film microstructure mechanism

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Effect of three-volt moxibustion with helium-neon laser irradiation on quality of care in patients with lumbar radiculopathy spondylosis

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World Journal of Clinical Cases 2024年第15期12卷 2522-2528页

作者： xiu-Kun Ji Jian Li Department of Traditional Chinese Medicine The Second Hospital of Heilongjiang ProvinceHarbin 150028Heilongjiang ProvinceChina Departments of Four Neurology The Second Hospital of Heilongjiang ProvinceHarbin 150028Heilongjiang ProvinceChina

BACKGROUND Lumbar radiculopathy spondylosis is a relatively common orthopedic disease with a high incidence rate.It most commonly occurs in the lumbar 4-5 and lumbar 5-sacral 1 vertebrae,which account for approximately 95%of cases.It mostly occurs in people aged 30-50 years old and greatly affects their quality of life.AIM To determine the effect of triple-voltage acupuncture combined with helium-neon laser irradiation on the quality of care and improvement of symptoms in patients with lumbar radiculopathy spondylolisthesis.METHODS In this study,we selected 120 patients with lumbar radiculopathy spondylosis who were treated at our hospital between June 2019 to June 2020.The patients were divided into control and observation groups according to the random number table method,with 60 patients in each group.Patients in the observation group were treated with three-volt moxibustion combined with helium-neon laser irradiation,and those in the control group were treated with lumbar traction.After 1 month of treatment,the lumbar pain scores,lumbar spine motor functions,clinical treatment effects,and nursing satisfaction of the two groups were compared.RESULTS The results showed that acupuncture combined with laser irradiation significantly improved the patients'clinical symptoms,i.e.,reduced their low back pain,significantly lower numerical rating scale pain scores in the observation group than in the control group,and better lumbar spine motility than in the control group,compared to lumbar traction.In addition,they were cared for.The treatment effectiveness rate of the observation group was 95.5%,which was significantly higher than that of the control group(81.67%).Satisfaction with care was higher than 90 points in both groups,but the difference was not statistically significant.CONCLUSION Our study provides a clinical rationale for the future treatment of patients with lumbar spine disease.However,further extensive research is needed for validation.

关键词： Moxibustion Laser irradiation Clinical rationale Lumbar spine Three-volt moxibustion

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Unusual Single Electron Transfer Reactions between Alkenes and Iodine Electrophiles

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Chinese Journal of Chemistry 2024年第5期42卷 471-477页

作者： Zhengzhao Lou Jingyu Hu Chuanfa Ni xiu Wang Jinbo Hu Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences345 Ling Ling RoadShanghai200032 China School of Physical Science and Technology ShanghaiTech University100 Haike RoadShanghai201210 China

The electrophilic addition to an alkene with an electrophile has been widely studied and applied in organic synthesis.The organic chemistry textbook describes the classical reaction between an alkene and an iodine electrophile(such as elemental iodine and N-iodosuccinimide(NIS))as a typical ionic reaction,in which an iodonium ion is formed and then attacked by a nucleophile.However,in this article,we report a new and unusual reaction mode between an alkene and NIS;that is,a single electron transfer(SET)process occurs between these two reactants by forming an electron-donor acceptor complex.Not only does this unusual single electron transfer reaction between an alkene and NIS add fundamentally important knowledge to organic chemistry,it also provides a valuable synthetic method as the new SET reaction mode with opposite regioselectivity as compared with the traditional ionic mode.

关键词： Electrophilic addition Radical ions Reaction mechanisms Alkenes Fluorine

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Rapid analysis of metal ions and organic compounds in strong acidic solutions by nano-ESI mass spectrometry

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Chinese Chemical Letters 2024年第2期35卷 516-520页

作者： Jiaquan Xu Ting Li Zhendong Yu Lili Song xiu-xiu Xu Hui Li Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation East China University of TechnologyNanchang 330013China Department of Rehabilitation Medicine The First Affiliated Hospital of Nanchang UniversityNanchang 330006China

Rapid analysis of metal ions and organic compounds in strong acidic solutions is of sustainable interest in multiple disciplines.However,complicated and time-consuming pretreatments are always required for MS analysis of the compounds in strong acidic solutions.Otherwise,it will result in a weak signal and cause serious damage to the mass spectrometer.herein,a simple method inherited from nano-ESI MS was developed for rapid analysis of strong acidic solutions.Nanoliter(nL)strong acidic solution was first loaded in the nano-ESI emitter,followed by evaporation to remove the H+and leave the analytes on the wall of the nano-ESI emitter.The evaporation process can be completed within 1 min because of the extremely tiny volume(≤1 nL)of the loaded solution.Then,the dried analytes on the wall of the nano-ESI emitter were redissolved by loading a new solvent,followed by nano-ESI MS analysis.By using this method,metal ions and organic compounds in the strong acidic solution can be detected with low sample consumption(1 nL),high speed(90%).Proof-of-concept applications of the present method have been successfully achieved for the analysis of gastric juice(pH of the sample=1),monitoring reaction catalyzed by strong acid(pH of the system=0),and micro-area analysis of ores(pH of the extraction solvent=0),showing great application potential in multiple fields.

关键词： Strong acidic solutions Nano-ESI MS Rapid analysis Reaction monitoring Micro-area analysis Gastric juice analysis

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Study of the Sensing Characteristics of Irradiated Fiber Bragg Gratings and Fabry-Perot Interferometers Under Gamma Radiation

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Photonic Sensors 2022年第1期12卷 91-98页

作者： Zhuoyue LI Zengling RAN Xianguo QING Zhengxi he Yaqin XIAO Tingting YANG xiu he Jialiang ZHU Peng he Sijie XU Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610213China Key Laboratory of Optical Fiber Sensing&Communications(Ministry of Education) University of Electronic Science and Technology of ChinaChengdu 611731China China Aerodynamics Research and Development Center Mianyang 621000China

The sensing characteristics of irradiated fiber Bragg gratings(FBGs)and Fabry-Perot interferometers(FPIs)were investigated under a 2MGy dose of gamma radiation.The study found that the pressure sensitivity of FP sensors after irradiation was stable,while the temperature sensitivity of FBG sensors was unstable,and both wavelengths displayed a shift.These findings offer the possibility for the application of FP pressure sensors in the gamma radiation environments,and FBG sensors require further research to be suitable for application in the nuclear radiation environments.

关键词： Fiber Bragg gratings Fabry-Perot interferometers gamma radiation

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Triceps skinfold thickness trajectories and the risk of all-cause mortality:A prospective cohort study

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World Journal of Clinical Cases 2024年第15期12卷 2568-2577页

作者： Na Yang Li-Yun he Zi-Yi Li Yu-Cheng Yang Fan Ping Ling-Ling Xu Wei Li Hua-Bing Zhang Yu-xiu Li Department of Endocrinology Key Laboratory of Endocrinology of National Health CommissionPeking Union Medical College HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China

BACKGROUND The measurement of triceps skinfold(TSF)thickness serves as a noninvasive metric for evaluating subcutaneous fat distribution.Despite its clinical utility,the TSF thickness trajectories and their correlation with overall mortality have not been thoroughly investigated.AIM To explore TSF thickness trajectories of Chinese adults and to examine their associations with all-cause mortality.METHODS This study encompassed a cohort of 14747 adults sourced from the China health and Nutrition Survey.Latent class trajectory modeling was employed to identify distinct trajectories of TSF thickness.Subjects were classified into subgroups reflective of their respective TSF thickness trajectory.We utilized multivariate Cox regression analyses and mediation examinations to explore the link between TSF thickness trajectory and overall mortality,including contributory factors.RESULTS Upon adjustment for multiple confounding factors,we discerned that males in the‘Class 2:Thin-stable’and‘Class 3:Thin-moderate’TSF thickness trajectories exhibited a markedly reduced risk of mortality from all causes in comparison to the‘Class 1:Extremely thin’subgroup.In the mediation analyses,the Geriatric Nutritional Risk Index was found to be a partial intermediary in the relationship between TSF thickness trajectories and mortality.For females,a lower TSF thickness pattern was significantly predictive of elevated all-cause mortality risk exclusively within the non-elderly cohort.CONCLUSION In males and non-elderly females,lower TSF thickness trajectories are significantly predictive of heightened mortality risk,independent of single-point TSF thickness,body mass index,and waist circumference.

关键词： Triceps skinfold thickness Trajectory All-cause mortality Body mass index Geriatric Nutritional Risk Index

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A Post-Quantum Cross-Domain Authentication Scheme Based on Multi-Chain Architecture

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Computers, Materials & Continua 2024年第2期78卷 2813-2827页

作者： Yi-Bo Cao xiu-Bo Chen Yun-Feng he Lu-Xi Liu Yin-Mei Che Xiao Wang Ke Xiao Gang Xu Si-Yi Chen Information Security Center State Key Laboratory ofNetworking and Switching TechnologyBeijing University of Posts and TelecommunicationsBeijing100876China Information Center of China North Industries Group Corporation Beijing100089China School of Information Science and Technology North China University of TechnologyBeijing100144China

Due to the rapid advancements in network technology,blockchain is being employed for distributed data storage.In the Internet of Things(IoT)scenario,different participants manage multiple blockchains located in different trust domains,which has resulted in the extensive development of cross-domain authentication techniques.However,the emergence of many attackers equipped with quantum computers has the potential to launch quantum computing attacks against cross-domain authentication schemes based on traditional cryptography,posing a significant security threat.In response to the aforementioned challenges,our paper demonstrates a post-quantum cross-domain identity authentication scheme to negotiate the session key used in the cross-chain asset exchange process.Firstly,our paper designs the hiding and recovery process of user identity index based on lattice cryptography and introduces the identity-based signature from lattice to construct a post-quantum cross-domain authentication scheme.Secondly,our paper utilizes the hashed time-locked contract to achieves the cross-chain asset exchange of blockchain nodes in different trust domains.Furthermore,the security analysis reduces the security of the identity index and signature to Learning With Errors(LWE)and Short Integer Solution(SIS)assumption,respectively,indicating that our scheme has post-quantum security.Last but not least,through comparison analysis,we display that our scheme is efficient compared with the cross-domain authentication scheme based on traditional cryptography.

关键词： Cross-domain identity authentication lattice-based cryptography blockchain hashed time-locked contract

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