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Catalytically generated noncovalent ammonium dienolate:a versatile platform for the development of organocatalytic asymmetric cascade reactions

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Science China Chemistry 2024年第8期67卷 2524-2546页

作者： Jun-Bing Lin dong-Sheng ji Peng-Fei Xu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China Shaanxi Key Laboratory of Chemical Reaction Engineering College of Chemistry and Chemical EngineeringYan’an UniversityYan’an 716000China

Organocatalytic cascade reactions represent a powerful strategy for the rapid construction of complex chiral molecules with multiple stereocenters from simple substrates under mild conditions. The intriguing structural feature and diverse reactivity of catalytically generated dienolate species render them competent and versatile intermediates for the development of practical and valuable cascade reactions. Over the past years, a plethora of innovative and pioneering noncovalent ammonium dienolatemediated cascade reactions have been designed and implemented under the catalysis of chiral organocatalysts, making dienolate activation a general, robust, and complementary method for the functionalization of unsaturated carbonyl compounds and related substances. This review illustrates the recent advances in organocatalytic noncovalent ammonium dienolate-mediated cascade reactions(mainly from 2010 to 2023), including the cascade transformations of ammonium dienolates directly generated from unsaturated ketone/aldehyde, ester/lactone/azlactone, amide/lactam/pyrazolone/oxindole, and alkylidene nitrile compounds. The contents are arranged based on the reaction types of the ammonium dienolates, with an emphasis on cascade 2,5-, 3,5-, and 4,5-difunctionalizations of these intermediates. Furthermore, other cascade reactions involving the 1,3-, 2,3-, and even more complex 3,4,5-reactivities of ammonium dienolates were also discussed. The reaction pathway, reaction stereoinduction, and synthetic applications of the ammonium dienolate-mediated cascade reactions were highlighted throughout the article. As a stimulating and ever-growing research area, the organocatalytic noncovalent ammonium dienolate-mediated cascade reactions are expected to continue demonstrating their magic power for constructing chiral targets in the future and further expanding the boundaries of asymmetric catalysis.

关键词： organocatalysis asymmetric catalysis ammonium dienolate cascade reaction difunctionalization

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Overview of computation strategies on the dispersion analysis for explicit finite difference solution of acoustic wave equation

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Petroleum Science 2024年第4期21卷 2311-2328页

作者： jian-Ping Huang Wei-Ting Peng ji-dong Yang Lu-Feng Lou School of Geosciences China University of Petroleum (East China) Pilot National Laboratory for Marine Science and Technology (Qingdao)

Finite-difference(FD) method is the most extensively employed numerical modeling technique. Nevertheless, when using the FD method to simulate the seismic wave propagation, the large spatial or temporal sampling interval can lead to dispersion errors and numerical instability. In the FD scheme, the key factor in determining both dispersion errors and stability is the selection of the FD weights. Thus,How to obtain appropriate FD weights to guarantee a stable numerical modeling process with minimum dispersion error is critical. The FD weights computation strategies can be classified into three types based on different computational ideologies, window function strategy, optimization strategy, and Taylor expansion strategy. In this paper, we provide a comprehensive overview of these three strategies by presenting their fundamental theories. We conduct a set of comparative analyses of their strengths and weaknesses through various analysis tests and numerical modelings. According to these comparisons, we provide two potential research directions of this field: Firstly, the development of a computational strategy for FD weights that enhances stability; Secondly, obtaining FD weights that exhibit a wide bandwidth while minimizing dispersion errors.

关键词： Finite-difference scheme FD coefficients Dispersion error Forward modeling Numerical simulation

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Successful splenic artery embolization in a patient with Behçet’s syndrome-associated splenic rupture:A case report

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World Journal of Gastrointestinal Surgery 2024年第4期16卷 1184-1188页

作者： Guang-Zhao Zhu dong-Hua ji Department of Interventional Therapy The First Affiliated Hospital of Dalian Medical UniversityDalian 116011Liaoning ProvinceChina

BACKGROUND Splenic rupture associated with Behçet’s syndrome(BS)is extremely rare,and there is no consensus on its *** this case report,a patient with BSassociated splenic rupture was successfully treated with splenic artery embolization(SAE)and had a good prognosis after the *** SUMMARY The patient was admitted for pain in the left upper abdominal *** was diagnosed with splenic *** oral and genital aphthous ulcers were observed,and acne scars were found on his *** had a 2-year history of BS diagnosis,with symptoms of oral and genital *** that time,he was treated with oral corticosteroids for 1 month,but the symptoms did not *** underwent SAE to treat the *** the first day after SAE,the patient reported a complete resolution of abdominal pain and was discharged 5 d *** months after the intervention,a computed tomography examination showed that the splenic hematoma had formed a stable cystic effusion,suggesting a good *** SAE might be a good choice for BS-associated splenic rupture based on good surgical practice and material selection.

关键词： Splenic artery embolization Behçet’s syndrome Splenic rupture Case report

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Accurate simulations of pure-viscoacoustic wave propagation in tilted transversely isotropic media

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Petroleum Science 2024年第2期21卷 866-884页

作者： Qiang Mao jian-Ping Huang Xin-Ru Mu ji-dong Yang Yu-jian Zhang Geosciences Department China University of Petroleum(East China)Qingdao266580ShandongChina Pilot National Laboratory for Marine Science and Technology(Qingdao) Qingdao266207ShandongChina

Forward modeling of seismic wave propagation is crucial for the realization of reverse time migration(RTM) and full waveform inversion(FWI) in attenuating transversely isotropic media. To describe the attenuation and anisotropy properties of subsurface media, the pure-viscoacoustic anisotropic wave equations are established for wavefield simulations, because they can provide clear and stable wavefields. However, due to the use of several approximations in deriving the wave equation and the introduction of a fractional Laplacian approximation in solving the derived equation, the wavefields simulated by the previous pure-viscoacoustic tilted transversely isotropic(TTI) wave equations has low accuracy. To accurately simulate wavefields in media with velocity anisotropy and attenuation anisotropy, we first derive a new pure-viscoacoustic TTI wave equation from the exact complex-valued dispersion formula in viscoelastic vertical transversely isotropic(VTI) media. Then, we present the hybrid finite-difference and low-rank decomposition(HFDLRD) method to accurately solve our proposed pure-viscoacoustic TTI wave equation. Theoretical analysis and numerical examples suggest that our pure-viscoacoustic TTI wave equation has higher accuracy than previous pure-viscoacoustic TTI wave equations in describing q P-wave kinematic and attenuation characteristics. Additionally, the numerical experiment in a simple two-layer model shows that the HFDLRD technique outperforms the hybrid finite-difference and pseudo-spectral(HFDPS) method in terms of accuracy of wavefield modeling.

关键词： Pure-viscoacoustic TTI wave equation Attenuation anisotropy Seismic modeling Low-rank decomposition method

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A reweighted damped singular spectrum analysis method for robust seismic noise suppression

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Petroleum Science 2024年第3期21卷 1671-1682页

作者： Wei-Lin Huang Yan-Xin Zhou Yang Zhou Wei-jie Liu ji-dong Li State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing2249China SINOPEC Petroleum Exploration and Production Research Institute Beijing102206China SINOPEC Geophysical Research Institute Nanjing211103jiangsuChina

(Multichannel)Singular spectrum analysis is considered as one of the most effective methods for seismic incoherent noise *** utilizes the low-rank feature of seismic signal and regards the noise suppression as a low-rank reconstruction ***,in some cases the seismic geophones receive some erratic disturbances and the amplitudes are dramatically larger than other *** presence of this kind of noise,called erratic noise,makes singular spectrum analysis(SSA)reconstruction unstable and has undesirable effects on the final *** robustify the low-rank reconstruction of seismic data by a reweighted damped SSA(RD-SSA)*** incorporates the damped SSA,an improved version of SSA,into a reweighted *** damping operator is used to weaken the artificial disturbance introduced by the low-rank projection of both erratic and random *** central idea of the RD-SSA method is to iteratively approximate the observed data with the quadratic norm for the first iteration and the Tukeys bisquare norm for the rest *** RD-SSA method can suppress seismic incoherent noise and keep the reconstruction process robust to the erratic *** feasibility of RD-SSA is validated via both synthetic and field data examples.

关键词： Singular spectrum analysis Damping operator Seismic erratic noise Seismic signal processing Robust low-rank reconstruction

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Brain circuits for retching-like behavior

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National Science Review 2024年第1期11卷 145-160页

作者： Lifang Huo Zhimin Ye Meiling Liu Ziqing He Meizhu Huang Dapeng Li Qian Wu Qian Wang Xiaoqun Wang Peng Cao ji dong Congping Shang School of Basic Medical Sciences Guangzhou National Laboratory The Fifth Afflliated Hospital Guangzhou Medical University Bioland Laboratory (Guangzhou Regenerative Medicine and Health Guangdong Laboratory) Department of Neurobiology School of Basic Medical Sciences Beijing Key Laboratory of Neural Regeneration and Repair Advanced Innovation Center for Human Brain Protection Capital Medical University State Key Laboratory of Cognitive Neuroscience and Learning IDG/McGovern Institute for Brain Research Beijing Normal University Changping Life Science Laboratory National Institute of Biological Sciences

Nausea and vomiting are important defensive responses to cope with pathogens and toxins that invade the body. The nucleus of the solitary tract(NTS) is important for initiating these responses. However, the molecular heterogeneities and cellular diversities of the NTS occlude a better understanding of these defensive responses. Here, we constructed the single-nucleus transcriptomic atlas of NTS cells and found multiple populations of NTS neurons that may be involved in these defensive responses. Among these, we identified Calbindin1-positive(Calb1+) NTS neurons that are molecularly distinct from Tac1+*** Calb1+neurons are critical for nausea and retching induced by cereulide; an emetic toxin secreted by Bacillus Cereus. Strikingly, we found that cereulide can directly modulate vagal sensory neurons that innervate Calb1+NTS neurons, a novel mechanism distinct from that for nausea and retching induced by Staphylococcal enterotoxin A. Together, our transcriptomic atlas of NTS neurons and the functional analyses revealed the neural mechanism for cereulide-induced retching-like behavior. These results demonstrate the molecular and cellular complexities in the brain that underlie defensive responses to the diversities of pathogens and toxins.

关键词： vomiting nausea nucleus of the solitary tract Calbindin1 neural circuits

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Superhydrophilic nickel hydroxide ultrathin nanosheets enable high-performance asymmetric supercapacitors

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Rare Metals 2024年第1期43卷 138-147页

作者： Yi-Ran Wang Fei Zhang jian-Min Gu Xiao-Yu Zhao Ran Zhao Xing Wang Tian-Hui Wu jing Wang ji-dong Wang De-Song Wang State Key Laboratory of Metastable Materials Science and Technology(MMST) Hebei Key Laboratory of Applied ChemistryYanshan UniversityQinhuangdao 066004China Department of Food and Pharmaceutical Engineering Suihua UniversitySuihua 152000China School of Chemical Science and Engineering Tongji UniversityShanghai 200092China School of Sciences Hebei University of Science and TechnologyShijiazhuang 050018China

Superhydrophilic surfaces have been applied for supercapacitor;however,during energy storage reaction,how the wettability affects the process of electrochemical reaction specifically is still ***,we demonstrate superhydrophilic surface for promotion of electrochemical reactions by liquid affinity and further explain the mechanism,where the transition of the wettability state caused by the change in surface free energy is the main reason for the obvious increase in specific *** citric acid assistance strategy,an intrinsically hydrophobic Ni(OH)_(2)thick nanosheets(HNHTNs,16 nm)can be transitioned into superhydrophilic Ni(OH)_(2)ultrathin nanosheets(SNHUNs,6.8 nm),where the water contact angle was 0°and the surface free energy increased from 8.6to 65.8 mN·m^(-1),implying *** with HNHTNs,the specific capacitance of SNHUNs is doubled:from 1230 F·g^(-1)(HNHTNs)to 2350 F·g^(-1)(2A·g^(-1))and,even at 20 A·g^(-1),from 833 F·g^(-1)(HNHTNs)to 1670 F·g^(-1).The asymmetric capacitors assembled by SNHUNs and activated carbon show 52.44 Wh·kg^(-1)at 160W·kg^(-1)and excellent stability with~90%retention after5000 cycles(~80%retention after 9500 cycles).The promotion of electrochemical performances is ascribed to the change of surface wettability caused by surface free energy,which greatly increase affinity of electrode to the surrounding liquid environment to reduce the interface resistance and optimize the electron transport path.

关键词： Asymmetric supercapacitor Superhydrophilic interface Transition metal hydroxides Ultrathin nanosheets High specific capacitance

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Organic Integration of Traditional Chinese and Western Medicines—Future of Clinical Practice Guidelines of Integrated Traditional Chinese and Western Medicines

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Chinese Journal of Integrative Medicine 2024年第4期30卷 359-365页

作者： XIE Ying-lan HAN Fei jiN Ying-hui DING Yan-bing GUO jing ji dong-xiao ZHANG Teng CHENXiao-min SHANG Hong-cai Department of Traditional Chinese Medicine Encephalopathy Hubei Provincial Hospital of Traditional Chinese MedicineWuhan(430074)China Department of Traditional Chinese Medicine Encephalopathy Hubei Province Traditional Chinese Medicine Research InstituteWuhan(430074)China Xuanwu Hospital of Traditional Chinese Medicine Beijing(100000)China Center for Evidence-Based and Translational Medicine Zhongnan Hospital of Wuhan UniversityWuhan(430074)China College of Acupuncture and Massage College of Health and RehabilitationNanjing University of Chinese MedicineNanjing(210023)China Department of Ophthalmology Huaihe Hospital of Henan UniversityKaifengHenan Province(475000)China Ministry of Education and Beijing Key Laboratory of Internal Medicine of Traditional Chinese Medicine Dongzhimen Hospital of Beijing University of Traditional Chinese Medicine/Ministry of Education and Beijing Key Laboratory of Internal Medicine of Traditional Chinese MedicineBeijing(100700)China

The transformation and implementation of clinical practice guidelines for integrated traditional Chinese medicine(TCM)and Western medicine(WM)is crucial to the adoption of medical science and technological findings and is an important way for TCM to be made available to the ***,clinical practice guidelines(CPGs)of TCM and WM integration in recent years was analyzed to clarify the current situation and problems in the existing guidelines according to the following four perspectives:(1)perspective of TCM and WM integration in guidelines,(2)diagnosis Using integrated TCM and WM,(3)integration of TCM and WM treatment,(4)promoting TCM and WM ***,the information and quality evaluation of CPGs for integrated Chinese and Western medicine in 2020–2022 were analyzed to explore the degree and methods of integration of Chinese and Western medicine *** last this study aimed to lay a foundation for the further establishment of Chinese characteristic,repeatable,and calculable clinical practice guidelines of TCM and WM integration.

关键词： clinical practice guidelines integrated traditional Chinese and Western medicine organic integration

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No Incidence of Liver Cancer Was Observed in A Retrospective Studyof Patients with Aristolochic Acid Nephropathy

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Chinese Journal of Integrative Medicine 2024年第2期30卷 99-106页

作者： SU Tao FANG Zhi-e GUO Yu-ming WANG Chun-yu WANG jia-bo ji dong BAI Zhao-fang YANG Li XiAO Xiao-he Renal Division Department of MedicinePeking University First HospitalBeijing(100034)China Department of Pharmacy Chongqing Hospital of Traditional Chinese MedicineChongqing(400021)China Department of Hepatology Fifth Medical Center of Chinese PLA General HospitalBeijing(100039)China China Military Institute of Chinese Materia Fifth Medical Center of Chinese PLA General HospitalBeijing(100039)China Phase I Clinical Trials Unit Department of Medicine for Infectious DiseasesFifth Medical Center of Chinese PLA General HospitalBeijing(100039)China Department of Pharmacy Affiliated Hospital of Shandong University of Traditional Chinese MedicineJinan(250000)China National Key Laboratory of Kidney Diseases Beijing(100039)China

Objective:To assess the risk of aristolochic acid(AA)-associated cancer in patients with AA nephropathy(AAN).Methods:A retrospective study was conducted on patients diagnosed with AAN at Peking University First Hospital from January 1997 to December ***-term surveillance and follow-up data were analyzed to investigate the influence of different factors on the prevalence of *** primary endpoint was the incidence of liver cancer,and the secondary endpoint was the incidence of urinary cancer during 1 year after taking AA-containing medication to ***:A total of 337 patients diagnosed with AAN were included in this *** the initiation of taking AA to the termination of follow-up,39 patients were diagnosed with *** cases of liver cancer were observed throughout the entire follow-up period,with urinary cancer being the predominant type(34/39,87.17%).Logistic regression analysis showed that age,follow-up period,and diabetes were potential risk factors,however,the dosage of the drug was not significantly associated with urinary ***:No cases of liver cancer were observed at the end of ***,a high prevalence of urinary cancer was observed in AAN *** a direct causality between AA and HCC is challenging.

关键词： aristolochic acid hepatocellular carcinoma urinary cancer drug safety retrospective study

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Synaptic Transmission of Primary Hippocampal Neurons was Enhanced after Terahertz Waves Exposure

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Biomedical and Environmental Sciences 2024年第8期37卷 926-930页

作者： Lequan Song Zhiwei He Junmiao Pan ji dong Haoyu Wang jing Zhang Binwei Yao XinpingXu Hui Wang Li Zhao Ruiyun Peng Beijing Institute of Radiation Medicine Beijing 100850China College of Education Hebei UniversityBaoding 071002HebeiChina

Terahertz(THz)waves,also known as T-rays,encompass frequencies ranging from 0.1 to 10 THz and possess unique properties that render them applicable in various biomedical domains,particularly in neurobiology[1].Synaptic transmission,the process through which signals propagate between neurons at synapses,is pivotal for brain function and information processing.

关键词： processing Waves render

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