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Metal-Carbene-TempIated Photochemistry in Solution: A Universal Route towards Cyclobutane Derivatives

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Chinese Journal of Chemistry 2019年第11期37卷 1147-1152,I0002页

作者： Yang Li guang-feng jin Yuan-Yuan An Rajorshi Das Ying-feng Han Key Laboratory of Synthetic and Natural Functional Molecule Chemistry College of Chemistry and Materials ScienceNorthwest UniversityXi'anShaanxi 710127China

Background and Originality Content Cyclobutane moieties are an important class of motifs since they are frequently found in the medicinally relevant compounds such as alkaloids and pharmaceuticals.[1] Therefore,the development of efficient synthetic strategies for the construction of cyclobutanes and their derivatives has always been a focus of inter-est.[2a] Photochemical reactions are powerful tools for synthesizing compounds with high complexity and diversity.[2b-h] Among them,photochemical[2+2]cycloaddition is a widely used protocol for the preparation of such compounds.[2h]However,this kind of reaction always suffers from the challenges of controlling the resulting products of the intermolecular[2+2]photodimerization.In principle,to achieve cyclobutanes via[2+2]cycloaddition,the two olefins should be oriented in a parallel fashion keeping the distance less than 4.2 A apart from each other.

关键词： butane photochemical alkaloids

Recent development of three-dimension printed graphene oxide and MXene-based energy storage devices

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Tungsten 2024年第1期6卷 196-211页

作者： Liang-Hao Yu Xin Tao Shang-Ru feng jin-Tao Liu Lin-Lin Zhang guang-Zhen Zhao guang Zhu Key Laboratory of Spin Electron and Nanomaterials of Anhui Higher Education Institutes Suzhou UniversitySuzhou 234000China Key Laboratory of Leather of Zhejiang Province College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325035China

The research for three-dimension(3D)printing carbon and carbide energy storage devices has attracted widespread exploration interests.Being designable in structure and materials,graphene oxide(GO)and MXene accompanied with a direct ink writing exhibit a promising prospect for constructing high areal and volume energy density devices.This review not only summarizes the recent advances in 3D printing energy storage devices including printing methods,ink rheological properties,and different energy storage systems,but also discusses the printing methods related to energy storage.In addition,the binder or additive free of two-dimensional carbide materials is quite important for the present electrochemical energy storage devices,which also are presented.

关键词： 3D printing Two-dimensional materials Energy storage device Ink theological MXene

Predictive visual field outcomes after optic chiasm decompressive surgery by retinal vessels parameters using optical coherence tomography angiography

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International Journal of Ophthalmology(English edition) 2024年第2期17卷 365-373页

作者： Wen-Juan Yu jin Xiao guang-Xin Wang Chang Jiang Wei Zha Rong-feng Liao Department of Ophthalmology the First Affiliated Hospital of Anhui Medical UniversityHefei 230022Anhui ProvinceChina Department of Neurosurgery the First Affiliated Hospital of Anhui Medical UniversityHefei 230022Anhui ProvinceChina Department of Ophthalmology the First People’s Hospital of HefeiHefei 230061Anhui ProvinceChina

AIM:To evaluate the predictive value of superficial retinal capillary plexus(SRCP)and radial peripapillary capillary(RPC)for visual field recovery after optic cross decompression and compare them with peripapillary nerve fiber layer(pRNFL)and ganglion cell complex(GCC).METHODS:This prospective longitudinal observational study included patients with chiasmal compression due to sellar region mass scheduled for decompressive surgery.Generalized estimating equations were used to compare retinal vessel density and retinal layer thickness preand post-operatively and with healthy controls.Logistic regression models were used to assess the relationship between preoperative GCC,pRNFL,SRCP,and RPC parameters and visual field recovery after surgery.RESULTS:The study included 43 eyes of 24 patients and 48 eyes of 24 healthy controls.Preoperative RPC and SRCP vessel density and pRNFL and GCC thickness were lower than healthy controls and higher than postoperative values.The best predictive GCC and pRNFL models were based on the superior GCC[area under the curve(AUC)=0.866]and the tempo-inferior pRNFL(AUC=0.824),and the best predictive SRCP and RPC models were based on the nasal SRCP(AUC=0.718)and tempo-inferior RPC(AUC=0.825).There was no statistical difference in the predictive value of the superior GCC,tempo-inferior pRNFL,and tempo-inferior RPC(all P>0.05).CONCLUSION:Compression of the optic chiasm by tumors in the saddle area can reduce retinal thickness and blood perfusion.This reduction persists despite the recovery of the visual field after decompression surgery.GCC,pRNFL,and RPC can be used as sensitive predictors of visual field recovery after decompression surgery.

关键词： sellar region mass retinal vessels optic chiasm optical coherence tomography angiography visual field decompressive surgery

Quantum phase transition of the Jaynes-Cummings model

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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 1-9页

作者： Cheng Liu jin-feng Huang Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Key Laboratory for Matter Microstructure and Function of Hunan ProvinceDepartment of Physics and Synergetic Innovation Center for Quantum Effects and ApplicationsInstitute of Interdisciplinary StudiesHunan Normal UniversityChangsha 410081China

Herein,we propose an experimentally feasible scheme to show the quantum phase transition of the Jaynes-Cummings(JC)model by modulating the transition frequency of a two-level system in a quantum Rabi model with strong coupling.By tuning the modulation frequency and amplitude,the ratio of the effective coupling strength of the rotating terms to the effective cavity(atomic transition)frequency can enter the deep-strong coupling regime,while the counter-rotating terms can be neglected.Thus,a deep-strong JC model is obtained.The ratio of the coupling strength to resonance frequencies in the deep-strong JC model is two orders of magnitude larger than the corresponding ratio in the original quantum Rabi model.Our scheme can be employed in atom-cavity resonance and off-resonance cases,and it is valid over a broad range.The nonzero average cavity photons of the ground state indicate the emergence of a quantum phase transition.Further,we demonstrate the dependence of the phase diagram on the atom-cavity detuning and modulation parameters.All the parameters used in our scheme are within the reach of current experimental technology.Our scheme provides a new mechanism for investigating the critical phenomena of finite-sized systems without requiring classical field limits,thereby opening a door for studying fundamental quantum phenomena occurring in the ultrastrong and even deep-strong coupling regimes.

关键词： Jaynes-Cummings model quantum phase transition frequency modulation

Simultaneous purification of minor components in natural products using twin-column recycling chromatography with a step solvent gradient

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Chinese Journal of Chemical Engineering 2024年第5期69卷 212-219页

作者： guangxia jin Yuxue Wu feng Wei School of Biological and Chemical Engineering NingboTech UniversityNingbo 315100China

The isolation of minor components from complex natural product matrices presents a significant challenge in the field of purification science due to their low concentrations and the presence of structurally similar compounds.This study introduces an optimized twin-column recycling chromatography method for the efficient and simultaneous purification of these elusive constituents.By introducing water at a small flowing rate between the twin columns,a step solvent gradient is created,by which the leading edge of concentration band would migrate at a slower rate than the trailing edge as it flowing from the upstream to downstream column.Hence,the band broadening is counterbalanced,resulting in an enrichment effect for those minor components in separation process.Herein,two target substances,which showed similar peak position in high performance liquid chromatography(HPLC)and did not exceed 1.8%in crude paclitaxel were selected as target compounds for separation.By using the twin-column recycling chromatography with a step solvent gradient,a successful purification was achieved in getting the two with the purity almost 100%.We suggest this method is suitable for the separation of most components in natural produces,which shows higher precision and recovery rate compared with the common lab-operated separation ways for natural products(thin-layer chromatography and prep-HPLC).

关键词： Solvent gradient Twin-column recycling chromatography Purification Minor component Natural products

Geophysical prediction of organic matter abundance in source rocks based on geochemical analysis:A case study of southwestern Bozhong Sag,Bohai Sea,China

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Petroleum Science 2024年第1期21卷 31-53页

作者： Xiang Wang guang-Di Liu Xiao-Lin Wang jin-feng Ma Zhen-Liang Wang Fei-Long Wang Ze-Zhang Song Chang-Yu Fan State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China College of Geosciences China University of Petroleum(Beijing)Beijing102249China State Key Laboratory of Continental Dynamics Northwest UniversityXi'an710069ShaanxiChina Department of Geology Northwest UniversityXi'an710069ShaanxiChina CNOOC Tianjin Branch Company Tianjin300459China

The Bozhong Sag is the largest petroliferous sag in the Bohai Bay Basin,and the source rocks of Paleogene Dongying and Shahejie Formations were buried deeply.Most of the drillings were located at the structural high,and there were few wells that met good quality source rocks,so it is difficult to evaluate the source rocks in the study area precisely by geochemical analysis only.Based on the Rock-Eval pyrolysis,total organic carbon(TOC)testing,the organic matter(OM)abundance of Paleogene source rocks in the southwestern Bozhong Sag were evaluated,including the lower of second member of Dongying Formation(E_(3)d2L),the third member of Dongying Formation(E_(3)d_(3)),the first and second members of Shahejie Formation(E_(2)s_(1+2)),the third member of Shahejie Formation(E_(2)s_(3)).The results indicate that the E_(2)s_(1+2)and E_(2)s_(3)have better hydrocarbon generative potentials with the highest OM abundance,the E_(3)d_(3)are of the second good quality,and the E_(3)d2L have poor to fair hydrocarbon generative potential.Furthermore,the well logs were applied to predict TOC and residual hydrocarbon generation potential(S_(2))based on the sedimentary facies classification,usingΔlogR,generalizedΔlogR,logging multiple linear regression and BP neural network methods.The various methods were compared,and the BP neural network method have relatively better prediction accuracy.Based on the pre-stack simultaneous inversion(P-wave impedance,P-wave velocity and density inversion results)and the post-stack seismic attributes,the three-dimensional(3D)seismic prediction of TOC and S_(2)was carried out.The results show that the seismic near well prediction results of TOC and S_(2)based on seismic multi-attributes analysis correspond well with the results of well logging methods,and the plane prediction results are identical with the sedimentary facies map in the study area.The TOC and S_(2)values of E_(2)s_(1+2)and E_(2)s_(3)are higher than those in E_(3)d_(3)and E_(3)d_(2)L,basically consistent with the geochemical analysis resul

关键词： Total organic carbon(TOC) Residual hydrocarbon generation potential(S_(2)) Geophysical prediction Seismic attribute Bozhong Sag Bohai Bay Basin

Electromagnetic fields in ultra-peripheral relativistic heavy-ion collisions

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Nuclear Science and Techniques 2024年第2期35卷 103-109页

作者： Jie Zhao jin-Hui Chen Xu-guang Huang Yu-Gang Ma Key Laboratory of Nuclear Physics and Ion-beam Application(MOE) Institute of Modern PhysicsFudan UniversityShanghai 200433China Shanghai Research Center for Theoretical Nuclear Physics NSFC and Fudan UniversityShanghai 200438China Physics Department and Center for Particle Physics and Field Theory Fudan UniversityShanghai 200438China

Ultra-peripheral heavy-ion collisions(UPCs)offer unique opportunities to study processes under strong electromagnetic fields.In these collisions,highly charged fast-moving ions carry strong electromagnetic fields that can be effectively treated as photon fluxes.The exchange of photons can induce photonuclear and two-photon interactions and excite ions.This excitation of the ions results in Coulomb dissociation with the emission of photons,neutrons,and other particles.Additionally,the electromagnetic fields generated by the ions can be sufficiently strong to enforce mutual interactions between the two colliding ions.Consequently,the two colliding ions experience an electromagnetic force that pushes them in opposite directions,causing a back-to-back correlation in the emitted neutrons.Using a Monte Carlo simulation,we qualitatively demonstrate that the above electromagnetic effect is large enough to be observed in UPCs,which would provide a clear means to study strong electromagnetic fields and their effects.

关键词： Electromagnetic fields Neutrons Ultra-peripheral relativistic heavy-ion collisions(UPC)

Multi-omics analyses of G6PD deficiency variants in Chinese population

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Journal of Genetics and Genomics 2024年第1期51卷 100-104页

作者： He Ji Jiahuan Chen Peide Huang Zhimin feng Weining Hu Mengyao Dai Xiaohui Sun Xiao jin guangquan Chen guang Ning Lin Li Weiqing Wang Yanan Cao Department of Endocrine and Metabolic Diseases Shanghai Institute of Endocrine and Metabolic DiseasesNational Clinical Research Centre for Metabolic DiseasesState Key Laboratory of Medical GenomicsResearch Unit of Clinical and Basic Research on Metabolic Diseases of Chinese Academy of Medical SciencesRuijin Yangtze River Delta Health InstituteWuxi Branch of Ruijin HospitalRuijin HospitalShanghai Jiao Tong University School of MedicineShanghai 200025China National Research Center for Translational Medicine National Key Scientific Infrastructure for Translational MedicineShanghai Jiao Tong UniversityShanghai 200240China SJTU-BGI Innovation Research Center Shanghai 200240China BGI-ShenZhen ShenzhenGuangdong 518083China

Glucose-6-phosphate dehydrogenase(G6PD)deficiency is one of the most prevalent hereditary and X-linked enzyme disorders caused by the pathogenetic G6PD(NM_001042351.2)variants(Yang et al.,2016).The clinical manifestations of G6PD deficiency offer a wide spectrum of diverse disease phenotypes(Hecker et al.,2013).Investigations of prevalence and molecular epidemiology demonstrate that G6PD deficiency affects over 400 milion individuals worldwide and leads to thousands of deaths annually(Mortality and Causes of Death,2015).

关键词： al. G6PD epidemiology

Tau truncation in the pathogenesis of Alzheimer's disease: a narrative review

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Neural Regeneration Research 2024年第6期19卷 1221-1232页

作者： Dandan Chu Xingyue Yang jing Wang Yan Zhou jin-Hua Gu jin Miao feng Wu Fei Liu Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education NMPA Key Laboratory for Research and Evaluation of Tissue Engineering Technology Products Coinnovation Center of Neuroregeneration Nantong University 2. Department of Pharmacology School of Pharmacy Nantong University 3. Department of Biochemistry and Molecular Biology School of Medicine Nantong University 4. Department of Clinical Pharmacy Affiliated Maternity and Child Health Care Hospital of Nantong University Nantong University 5. Laboratory of Animal Center Nantong University Department of Neurochemistry Inge Grundke-Iqbal Research Floor New York State Institute for Basic Research in Developmental Disabilities

Alzheimer’s disease is characterized by two major neuropathological hallmarks—the extracellular β-amyloid plaques and intracellular neurofibrillary tangles consisting of aggregated and hyperphosphorylated Tau protein. Recent studies suggest that dysregulation of the microtubuleassociated protein Tau, especially specific proteolysis, could be a driving force for Alzheimer’s disease neurodegeneration. Tau physiologically promotes the assembly and stabilization of microtubules, whereas specific truncated fragments are sufficient to induce abnormal hyperphosphorylation and aggregate into toxic oligomers, resulting in them gaining prion-like characteristics. In addition, Tau truncations cause extensive impairments to neural and glial cell functions and animal cognition and behavior in a fragment-dependent manner. This review summarizes over 60 proteolytic cleavage sites and their corresponding truncated fragments, investigates the role of specific truncations in physiological and pathological states of Alzheimer’s disease, and summarizes the latest applications of strategies targeting Tau fragments in the diagnosis and treatment of Alzheimer’s disease.

关键词： Alzheimer’s disease cleavage site diagnosis marker neurofibrillary tangles phosphorylation Tau Tau aggregation therapy truncation