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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 *** study introduces an optimized twin-column recycling chromatography method for the efficient and simultaneous purification of these elusive *** 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 ***,the band broadening is counterbalanced,resulting in an enrichment effect for those minor components in separation ***,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 *** 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

Intestinal erosion caused by meshoma displacement:A case report

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World Journal of Gastrointestinal Surgery 2023年第1期15卷 114-120页

作者： jin-feng wu Jian Chen Fang Hong Department of General Surgery Tongde Hospital of Zhejiang ProvinceHangzhou 310012Zhejiang ProvinceChina Department of Gynaecology and Obstetrics Zhejiang University School of Medicine Sir Run Run Shaw HospitalHangzhou 310016Zhejiang ProvinceChina

BACKGROUND A meshoma formation and erosion to the small intestine is ***,we report one case of a meshoma that was not treated early;causing it to displace and erode the small intestine,with infection,complete control of symptoms was achieved after removal of the infected patch mass,no recurrence of hernia after 2 years of *** SUMMARY A 62-year-old male patient presented with recurrent abdominal pain repeatedly for 1 wk,which has worsened 2 d before admition,accompanied by *** years before presentation he underwent right inguinal hernia Plug and patch repair *** years ago,a computed tomography scan revealed a right lower abdominal mass with soft tissue density,measuring approximately 30 mm×17 mm,which was diagnosed as meshoma that was not *** patient had poorly controlled diabetes in the past *** The formation of meshoma is rare,and that if not treated in time it might erode and require resection of the involved organ.

关键词： Tension-Free mesh repair Polypropylene mesh Meshoma Mesh infection Bowel resection Case report

Numerical simulation of the 3D flow field in a ring die pellet mill considering viscous heating

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International Journal of Modeling, Simulation, and Scientific Computing 2020年第3期11卷 135-153页

作者： Yong-Mei Wang Xiao-Peng Huang jin-feng wu Wan-Xia Yang College of Mechanical and Electrical Engineering Gansu Agricultural University Lanzhou 730070P.R.China

Viscous heating has a substantial influence on the extrusion forming process and product quality of powder *** study selected the MUZL420 ring die pellet mill as the research object,from which a 3D flow physical model was *** numerical simulation of 3D nonisothermal flow in the extrusion pelletizing process of granulated alfalfa was performed with *** distribution laws of pressure,velocity,shear rate,viscosity,viscous heating and temperature in the flow field were revealed to thoroughly investigate the pelletizing process and provide a reference for structural optimization and process *** results showed that two extrusion zones in the pelleting chamber were symmetrical with respect to the center,and the significant pressure gradient along the rotating direction of the ring die and the roller caused the material to flow back in the opposite *** were larger velocity gradients,shear rates and viscous heating levels in the deformation and compaction zone,the negative pressure zone behind the extrusion zone and the die *** distribution of viscosity was opposite to that of the shear *** temperature increase area caused by viscous heating gradually expanded from the material inlet to the bottom of the extrusion chamber along the Z-axis direction,and the temperature increased *** extrusion force and the forming temperature in the extrusion forming zone were captured in the numerical *** extrusion forming density was calculated with the regression prediction model established through the simulation experiment of pelletizing with a ring *** a comparison with the results of mean alfalfa pellet density from the ring die pellet mill experiment,the relative error was less than 5%,which indicated that the numerical simulation method was reliable.

关键词： Ring die pellet mill viscous heating 3D flow field numerical simulation

Artificial rabbit optimization algorithm based on chaotic mapping and Levy flight improvement

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The Journal of China Universities of Posts and Telecommunications 2024年第4期31卷 54-69页

作者： wu jin Su Zhengdong Gao Yaqiong feng Haoran School of Electronic Engineering Xi’an University of Posts and TelecommunicationsXi’an 710121China

An artificial rabbit optimization(ARO)algorithm based on chaotic mapping and Levy flight improvement is proposed,which has the advantages of good initial population quality and fast convergence compared with the traditional ARO algorithm,called *** is improved by applying three *** mapping is introduced,which can optimize the quality of the initial population of the *** Levy flight in the exploration phase,which can avoid the algorithm from falling into a local *** threshold of the energy factor is optimized,which can better balance exploration and *** efficiency of CLARO is tested on a set of 23 benchmark function sets by comparing it with ARO and different meta-heuristics *** last,the comparison experiments conclude that all three improvement strategies enhance the performance of ARO to some extent,with Levy flight providing the most significant improvement in ARO *** experimental results show that CLARO has better results and faster convergence compared to other algorithms,while successfully addressing the drawbacks of ARO and being able to face more challenging problems.

关键词： CLARO chaotic mapping Levy flight convergence

5-min mindfulness audio induction alleviates psychological distress and sleep disorders in patients with COVID-19

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World Journal of Clinical Cases 2022年第2期10卷 576-584页

作者： jing Li Yun-Yun Zhang Xiao-Yin Cong Shu-Rong Ren Xiao-Ming Tu jin-feng wu Department of Geriatrics The First Affiliated Hospital of Nanjing Medical UniversityNanjing 210029Jiangsu ProvinceChina Department of Psychology The First Affiliated Hospital of Nanjing Medical UniversityNanjing 210029Jiangsu ProvinceChina Nanjing Medical University Nanjing 211166Jiangsu ProvinceChina

BACKGROUND Mindfulness meditation is beneficial to mitigate the negative effects of the coronavirus disease 2019(COVID-19)pandemic in the general population,but no study examined such meditation in the COVID-19 patients *** To explore the short-term efficacy of mindfulness meditation in alleviating psychological distress and sleep disorders in patients with *** This prospective study enrolled patients with mild COVID-19 treated at wuhan Fangcang Hospital in February *** patients were voluntarily divided into either a mindfulness or a conventional intervention *** patients were evaluated before/after the intervention using the Short Inventory of Mindfulness Capability(SMI-C),Hospital Anxiety and Depression Scale(HADS),and Pittsburgh Sleep Quality Index(PSQI).RESULTS Seventy-five participants were enrolled in this study,with 43 and 32 in the mindfulness and conventional groups,*** the intervention,there were no differences in SMI-C,HADS,or PSQI scores between the two *** the 2-wk intervention,the mindfulness level(from 30.16±5.58 to 35.23±5.95,P<0.001)and sleep quality(from 12.85±3.06 to 9.44±3.86,P<0.001)were significantly increased in the mindfulness *** were no differences in the conventional *** the intervention,the mindfulness level(35.23±5.95 vs 31.17±6.50,P=0.006)and sleep quality(9.44±3.86 vs 11.87±4.06,P=0.011)were significantly higher in the mindfulness group than in the conventional *** decreased in the mindfulness group(from 14.15±3.21 to 12.50±4.01,P=0.038),but there was no difference between the two *** Short-term mindfulness meditation can increase the mindfulness level,improve the sleep quality,and decrease the depression of patients with COVID-19.

关键词： COVID-19 Mindfulness Mental health Sleep quality

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 ProductsCoinnovation Center of NeuroregenerationNantong UniversityNantongJiangsu ProvinceChina Department of Pharmacology School of PharmacyNantong UniversityNantongJiangsu ProvinceChina Department of Biochemistry and Molecular Biology School of MedicineNantong UniversityNantongJiangsu ProvinceChina Department of Clinical Pharmacy Affiliated Maternity and Child Health Care Hospital of Nantong UniversityNantong UniversityNantongJiangsu ProvinceChina Laboratory of Animal Center Nantong UniversityNantongJiangsu ProvinceChina Department of Neurochemistry Inge Grundke-Iqbal Research FloorNew York State Institute for Basic Research in Developmental DisabilitiesStaten IslandNYUSA

Alzheimer's disease is characterized by two major neuropathological hallmarks—the extracellularβ-amyloid plaques and intracellular neurofibrillary tangles consisting of aggregated and hyperphosphorylated Tau *** studies suggest that dysregulation of the microtubuleassociated protein Tau,especially specific proteolysis,could be a driving force for Alzheimer's disease *** 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 *** addition,Tau truncations cause extensive impairments to neural and glial cell functions and animal cognition and behavior in a fragment-dependent *** 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

Enhancing the Circularly Polarized Luminescence of Self-assembled Cyanostilbenes through Extended π-Conjugation

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Chinese Journal of Chemistry 2024年第2期42卷 135-141页

作者： Tongjin Lv Song wu Yu jin Jianfei Ma Sixun Jiang Yuncong Xue feng Wang Key Laboratory of Precision and Intelligent Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefeiAnhui 230026China Department of Thoracic Surgery Shanghai Jiao Tong University Affiliated Sixth People's HospitalShanghai 200233China

Chiral supramolecular assembly of π-conjugated luminophores provides a promising avenue for enhancing circularly polarized *** this study,we shed light on the impact of π-conjugation length on circularly polarized luminescent performance of the resulting supramolecular assemblies,by designing a tetra-cyanostilbene monomeric compound alongside two dicyanostilbene control *** cyanostilbene-based compounds possess the ability to form chiral supramolecular polymers in toluene,driven by a synergistic combination of intermolecular hydrogen bonding and π-stacking *** extended π π-aromatic skeleton brings bathochromic-shifted fluorescence and enhanced intermolecular stacking capability for the tetra-cyanostilbene ***,chiral supramolecular assemblies formed by the tetra-cyanostilbene compound demonstrate a remarkable two-fold increase in g_(lum) values relative to the assemblies formed by the dicyanostilbene ***,this study provides valuable insights into the relationship between-conjugation length and the circularly polarized luminescent performance of π-conjugatedsupramolecularassemblies.

关键词： Self-assembly Supramolecular polymer Supramolecular chirality Circularly polarized luminescence Cyanostilbene πInteractions Aggregation Nanostructures

Multiple lines of evidence supports the two varieties of Halenia elliptica(Gentianaceae)as two species

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Plant Diversity 2022年第3期44卷 290-299页

作者： jin-feng wu Dong-Rui Jia Rui-Juan Liu Zhi-Li Zhou Lin-Lin Wang Min-Yu Chen Li-Hua Meng Yuan-Wen Duan School of Life Sciences Yunnan Normal UniversityKunming 650092PR China School of Ecology and Environmental Science&Yunnan Key Laboratory for Plateau Mountain Ecology and Restoration of Degraded Environments Yunnan UniversityKunming 650091PR China Northwest Institute of Plateau Biology Chinese Academy of SciencesXining 810001PR China The Germplasm Bank of Wild Species Institute of Tibetan Plateau Research at KunmingKunming Institute of BotanyChinese Academy of SciencesKunming 650201YunnanPR China Yunnan Lijiang Forest Ecosystem National Observation and Research Station Kunming Institute of BotanyChinese Academy of SciencesLijiang 674100YunnanPR China

Delimiting species requires multiple sources of ***,we delimited two varieties of Halenia elliptica(Gentianaceae)using several lines of evidence,including morphological traits and mating system in a sympatric population,phylogenetic relationships based on nrITS and cpDNA(rpl16)data,and complete chloroplast genome *** analysis of 21 morphological traits clearly separates the two varieties of *** of the flowering process and pollination treatments indicate that *** *** produces seeds via outcrossing,whereas *** *** produces seeds via mixed ***,hand-pollinated hybridization of the two varieties produced no *** of pollinators showed that when bees began a pollination bout on *** *** they preferred to continue pollinating this variety;however,when they began a pollination bout on *** ***,they showed no preference for either *** analysis confirmed the monophyly of ***,which was further divided into two monophyletic clades corresponding to the two varieties.A large number of variants from the chloroplast genomes reflected remarkable genetic dissimilarities between the two varieties of *** recommend that the two varieties of *** should be revised as two species(*** and ***).Our findings indicate that *** varieties may have split into two separate species due to a shift in mating system,changes in flowering phenology and/or post-pollination reproductive isolation.

关键词： Halenia elliptica Flowering phenology Mating system Reproductive isolation Monophyly Species delimitation

Flow instability of supercritical hydrocarbon fuel in a multi-channel cooling system

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Chinese Journal of Aeronautics 2024年第2期37卷 283-295页

作者： Yichao jin Kun wu Xuejun FAN Institute of Applied Physics and Computational Mathematics Beijing 100094China Institute of Mechanics Chinese Academy of SciencesBeijing 100190China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China

Thermally-induced flow instabilities are a critical issue in multi-channel regenerative cooling *** particular,the interactions between Density-Wave Oscillations(DWO)and Flow Maldistribution(FMD)can result in complex and disastrous instability *** study investigates the instability behaviors of hydrocarbon fluid in a four-channel system with a constant heat flux ratio using both frequency-and time-domain *** the heat flux increases,the in-tube flow sequentially destabilizes in each channel and converges to new equilibrium states,leading to the emergence of FMD *** also causes the system eigenvalue to change repeatedly from negative to positive rather than increasing ***,the system eigenvalues are between those of the two most unstable channels,indicating that the stability behavior of the entire system is dictated by the most unstable *** FMD occurs,flow oscillations are activated in channels with weak stability,and the in-tube flow is observed to evolve into various flow patterns,including stable flow,self-sustained oscillation,oscillation divergence,quasiperiodic oscillation,and oscillation *** novel instability mode of oscillation excursion involves a spontaneous transition of operating *** oscillates from an equilibrium state and then stabilizes at a new operational state after oscillation-induced ***,the newfound stable state may also be only temporary,with the in-tube flow regressing to the initial state,resulting in quasi-periodic oscillation.

关键词： Cooling Supercritical fluids Hydrocarbons Flow instability Flow maldistribution Density-wave oscillations