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Science China Chemistry 2024年第11期67卷 3791-3797页

作者： Debasis pal Kirana D.Veeranna Yuk fai Wong p.Andrew Evans Department of Chemistry Queen's University Xiangya School of pharmaceutical Sciences Central South University

The Reformatsky reagent derived from ethyl bromoacetate circumvents the challenge associated with the direct regio-and enantioselective iridium-catalyzed allylic alkylation with an unstabilized aliphatic ester enolate. Notably, this work represents the first example of using a Reformatsky reagent in a metal-allyl reaction, which permits the direct construction of enantioenriched β-stereogenic homoallylic esters without preactivation of the pronucleophile or post-reaction modification of the product(e.g., thermal decarboxylation of a 1,3-dicarbonyl). Moreover, the process allows the coupling of a broad range of sterically and electronically diverse electrophiles bearing aryl, heteroaryl and alkenyl derivatives, including the significantly more challenging alkyl-substituted allylic carbonates. The versatility of the ester product is exemplified by a series of functional group manipulations and the development of a concise and efficient enantioselective total synthesis of the natural product,(+)-descurainolide A. finally, mechanistic studies indicate that the zinc enolate behaves as a soft nucleophile that undergoes outer-sphere alkylation.

关键词： allylic substitution asymmetric catalysis mechanistic studies natural product synthesis Reformatsky reagent

The Value of Traditional Medicine Should not be Underestimated-Traditional Chinese Medicine in Treatment of Autoimmune Diseases

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Chinese Medicine and Culture 2024年第2期7卷 167-173页

作者： Yurii O Novikov Anait p Akopyan Bashkir State Medical University Republic of BashkortostanRussia 450008

Autoimmune diseases of the nervous system(ADNS)are characterized by the formation of a pronounced neurologic deficit and often lead to *** attention of doctors and researchers is increasingly attracted by complementary medicine as adjuvant or preventive therapy for various diseases,including autoimmune *** Chinese medicine(TCM)is a combination of treatment methods that include acupuncture,herbal medicine,dietetics,physical exercises,and other methods that are often used in conjunction with recognized approaches of official medical *** article describes the application of TCM techniques in autoimmune diseases of the nervous system,and demonstrates clinical experience in the use of acupuncture,herbal medicine,diets and physical *** and complementary medicine is an important and often underestimated healthcare resource,especially in the prevention and treatment of autoimmune diseases of the nervous system.

关键词： Autoimmune diseases Traditional Chinese medicine Nervous diseases

performance of unique and secure routing protocol(USRp)in flying Adhoc Networks for healthcare applications

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High-Confidence Computing 2024年第1期4卷 24-31页

作者： J.Vijitha Ananthi p.Subha Hency Jose Department of Biomedical Engineering Karunya Institute of Technology and SciencesCoimbatoreIndia

Nowadays,flying Adhoc Networks play a vital role due to its high efficiency in fast *** aerial vehicles transmit data much faster than other networks and are useful in all aspects of *** healthcare applications,wireless body area network transmits the data,whereas the security,which is the most important concern to be focused in a flying adhoc network is not *** intruders tamper the network,degrading the overall network *** avoid security issues,a unique and secure routing protocol that provides a single solution for five different types of attacks such as,black hole attacks,grey hole attacks,yoyo attacks,conjoint attack and jamming attacks,is *** simulation results analyses the network performance by using the proposed routing *** comparison to the other solutions rendered to resolve the affected network,this proposed routing protocol has a higher throughput,higher delivery rate,and lower *** Unique and Secure Routing protocol(USRp)provides an integrated solution for an efficient and secure communication in a flying adhoc network.

关键词： Secure routing protocol flying Adhoc Networks Unmanned aerial vehicles Mobile Adhoc network Attackers Denial of service attacks

Technological achievements in the fabrication of tubular-designed protonic ceramic electrochemical cells

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Materials futures 2024年第4期3卷 71-106页

作者： Maria A Gordeeva Artem p Tarutin Nikolai A Danilov Dmitry A Medvedev Laboratory of Electrochemical Devices Based on Solid Oxide proton Electrolytes Institute of High-Temperature Electrochemistry620066 EkaterinburgRussia Hydrogen Energy Laboratory Ural Federal University620002 EkaterinburgRussia

protonic ceramic electrochemical cells provide an excellent basis for the advancement of high-temperature solid oxide devices,offering potential solutions to a range of challenges in the hydrogen energy and carbon capture *** facilitated ionic transport in proton-conducting electrolytes enables these cells to operate at temperatures 100◦C–500◦C lower than those of conventional solid oxide cells with known zirconia *** a result,promising performances have been reported for various types of proton ceramic electrochemical ***,these advancements have been demonstrated only at the laboratory scale,whereas their ZrO2-based counterparts have already been *** review presents an overview of the fundamental and applied aspects related to the fabrication of tubular protonic ceramic electrochemical cells and their subsequent characterization as hydrogen permeation membranes,hydrogen pumps,hydrogen sensors,fuel cells,electrolysis cells,and electrochemical reactors.A specific focus is placed on the technological aspects of the tube preparations derived from the original powder sources as well as the dimensional characteristics of the tubes,which serve as an indicator of ***,this review serves as a starting point for the development and scaling of protonic ceramic electrochemical cells,with the potential for large-scale production.

关键词： electrochemistry energy conversion hydrogen proton transport perovskite solid oxide cells scaling

A predictive model for ethylene-mediated auxin and cytokinin patterning in the Arabidopsis root

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plant Communications 2024年第7期5卷 120-137页

作者： Simon Moore George Jervis Jennifer f.Topping Chunli Chen Junli Liu Keith Lindsey Department of Biosciences Durham UniversitySouth RoadDurham DH13LEUK Hubei Hongshan Laboratory College of Life Science and TechnologyHuazhong Agricultural UniversityWuhan 430070China National Key Laboratory for Germplasm Innovation and Utilization for fruit and Vegetable Horticultural Crops Huazhong Agricultural UniversityWuhanHubei 430070China

The interaction between auxin and cytokinin is important in many aspects of plant *** measurements of both auxin and cytokinin concentration and reporter gene expression clearly show the coexistence of auxin and cytokinin concentration patterning in Arabidopsis root ***,in the context of crosstalk among auxin,cytokinin,and ethylene,little is known about how auxin and cytokinin concentration patterns simultaneously emerge and how they regulate each other in the Arabidopsis *** work utilizes a wide range of experimental observations to propose a mechanism for simultaneous patterning of auxin and cytokinin *** addition to revealing the regulatory relationships between auxin and cytokinin,this mechanism shows that ethylene signaling is an important factor in achieving simultaneous auxin and cytokinin patterning,while also predicting other experimental *** the mechanism with a realistic in silico root model reproduces experimental observations of both auxin and cytokinin *** made by the mechanism can be compared with a variety of experimental observations,including those obtained by our group and other independent experiments reported by other *** of these predictions include patterning of auxin biosynthesis rate,changes in pIN1 and pIN2 patterns in pin3,4,7 mutants,changes in cytokinin patterning in the pls mutant,pLS patterning,and various trends in different *** research reveals a plausible mechanism for simultaneous patterning of auxin and cytokinin concentrations in Arabidopsis root development and suggests a key role for ethylene pattern integration.

关键词： Arabidopsis root auxin patterning cytokinin patterning ethylene signaling in silico digital root spatiotemporal modeling

Bile acid signaling in the regulation of whole body metabolic and immunological homeostasis

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Science China(Life Sciences) 2024年第5期67卷 865-878页

作者： Wei Jia Yitao Li Kenneth C.p.Cheung Xiaojiao Zheng School of Chinese Medicine Hong Kong Baptist UniversityHong KongChina Center for Translational Medicine and Shanghai Key Laboratory of Diabetes Mellitus Shanghai Sixth People's Hospital Affiliated to Shanghai JiaoTong University School of MedicineShanghai 200233China

Bile acids(BAs)play a crucial role in nutrient absorption and act as key regulators of lipid and glucose metabolism and immune *** the enterohepatic circulation,BAs are synthesized,metabolized,and reabsorbed,with a portion entering the vascular circulation and distributing *** allows BAs to interact with receptors in all major organs,leading to organ-organ interactions that regulate both local and global metabolic processes,as well as the immune *** review focuses on the whole-body effects of BA-mediated metabolic and immunological regulation,including in the brain,heart,liver,intestine,eyes,skin,adipose tissue,and *** BA synthesis and receptor signaling is a promising strategy for the development of novel therapies for various diseases throughout the body.

关键词： bile acid whole body metabolism immunity

Downstaging strategies for unresectable hepatocellular carcinoma

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World Journal of Gastroenterology 2024年第20期30卷 2731-2733页

作者： Georgia Sofia Karachaliou Nikolaos Dimitrokallis Dimitrios p Moris Division of Gastroenterology Department of MedicineDuke University Medical CenterDurhamNC 27710United States first Department of Surgery&Organ Transplant Unit Evangelismos General HospitalAthens 10676Greece Department of Surgery Duke University Medical CenterDurhamNC 27710United States

A significant number of patients with hepatocellular carcinoma(HCC)are usually diagnosed in advanced stages,that leads to inability to achieve *** options are focusing on downstaging a locally advanced *** is wellsupported in the literature that patients with HCC who undergo successful conversion therapy followed by curative-intent surgery may achieve a significant survival benefit compared to those who receive chemotherapy alone or those who are successfully downstaged with conversion therapy but not treated with *** artery infusion chemotherapy can be a potential downstaging strategy,since recent studies have demonstrated excellent outcomes in patients with colorectal liver metastatic disease as well as primary liver malignancies.

关键词： Unresectable hepatocellular carcinoma Hepatic arterial infusion chemotherapy Downstaging Hepatocellular carcinoma

MDCN:Modified Dense Convolution Network Based Disease Classification in Mango Leaves

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Computers, Materials & Continua 2024年第2期78卷 2511-2533页

作者： Chirag Chandrashekar K.p.Vijayakumar K.pradeep A.Balasundaram School of Computer Science and Engineering Vellore Institute of Technology(VIT)ChennaiIndia Center for Cyber physical Systems School of Computer Science and EngineeringVellore Institute of Technology(VIT)ChennaiIndia

The most widely farmed fruit in the world is *** the production and quality of the mangoes are hampered by many *** diseases need to be effectively controlled and ***,a quick and accurate diagnosis of the disorders is *** convolutional neural networks,renowned for their independence in feature extraction,have established their value in numerous detection and classification ***,it requires large training datasets and several parameters that need careful *** proposed Modified Dense Convolutional Network(MDCN)provides a successful classification scheme for plant diseases affecting mango *** model employs the strength of pre-trained networks and modifies them for the particular context of mango leaf diseases by incorporating transfer learning *** data loader also builds mini-batches for training the models to reduce training ***,optimization approaches help increase the overall model’s efficiency and lower computing *** employed on the MangoLeafBD Dataset consists of a total of 4,000 *** the experimental results,the proposed system is compared with existing techniques and it is clear that the proposed algorithm surpasses the existing algorithms by achieving high performance and overall throughput.

关键词： Leaf disease detection deep convolutional neural networks transfer learning optimization MangoLeafBD Dataset

Effect of dry-wet cycles on dynamic properties and microstructures of sandstone:Experiments and modelling

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International Journal of Mining Science and Technology 2024年第5期34卷 655-679页

作者： Hai pu Qingyu Yi Andrey p.Jivkov Zhengfu Bian Weiqiang Chen Jiangyu Wu State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Earth Engineering China University of Mining and TechnologyXuzhou 221116China Key Laboratory of Xinjiang Coal Resources Green Mining Ministry of EducationXinjiang Institute of EngineeringUrumqi 830023China Department of Solids and Structures School of EngineeringUniversity of ManchesterManchester M139PLUK School of Environment Science and Spatial Informatics China University of Mining and TechnologyXuzhou 221116China Department of Civil and Environmental Engineering Rice UniversityHouston 77005USA State Key Laboratory of High performance Civil Engineering Materials Jiangsu Research Institute of Building Science Co.Ltd.Nanjing 210008China Department of Materials University of OxfordOxford OX13PHUK

Underground pumped storage power plant(UpSp)is an innovative concept for space recycling of abandoned *** realization requires better understanding of the dynamic performance and durability of reservoir *** paper conducted ultrasonic detection,split Hopkinson pressure bar(SHpB)impact,mercury intrusion porosimetry(MIp),and backscatter electron observation(BSE)tests to investigate the dynamical behaviour and microstructure of sandstone with cyclical dry-wet damage.A coupling fEM-DEM model was constructed for reappearing mesoscopic structure *** results show that dry-wet cycles decrease the dynamic compressive strength(DCS)with a maximum reduction of 39.40%,the elastic limit strength is reduced from 41.75 to 25.62 *** sieved fragments obtain the highest crack growth rate during the 23rd dry-wet cycle with a predictable life of 25 cycles for each rock *** pore fractal features of the macropores and micro-meso pores show great differences between the early and late cycles,which verifies the computational statistics analysis of particle *** numerical results show that the failure patterns are governed by the strain in pre-peak stage and the shear cracks are *** dry-wet cycles reduce the energy transfer efficiency and lead to the discretization of force chain and crack fields.

关键词： Underground pumped storage power plant Dry-wet cycles Split Hopkinson pressure bar Macro and micro properties fEM-DEM coupling model Damage characterization

Solid-liquid extraction for yttrium recovery using porous polymeric resin(XAD-7) functionalized with D_(2)EHpA

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Journal of Rare Earths 2024年第9期42卷 1764-1773,I0005页

作者： p.A.Martínez-Montoya R.G.Sanchez-Alvarado D.Y.Medina-Velazquez M.L.Carrera-Jota p.Garnica-Chávez A.de J.Morales-Ramirez Higher School of Chemical Engineering and Extractive Industries ESIQIEIPNDepartment of Metallurgical EngineeringUPALM S/NCol.LindavistaGustavo A.Madero Cd.de MéxicoC.P07738Mexico Metropolitan Autonomous University Department of MaterialsBasic Sciences and EngineeringAv.San Pablo No.180Col.Reynosa TamaulipasCd.de MéxicoC.P02200Mexico Center for Research and Technological Innovation CIITECIPNCda.de CECATIs/nSanta CatarinaAzcapotzalcoC.P02250CDMXMexico

The recovery of yttrium is proposed by applying a solid-liquid extraction process using di-2-ethyl hexylphosphoric acid(D2EHpA) as extracting *** extracting agents were supported on a macro porous polymeric resin XAD-7(solid phase).Yttrium ions extraction and discharge tests were performed,firstly from a synthetic aqueous solution of 100 mg/L Y(liquid phase) at 25℃ with *** effects of pH of aqueous solutions bearing yttrium,volume fraction of extracting agents and the solid/liquid(S/L)ratio on the yttrium recovery were *** most favorable conditions for yttrium ions extraction are;20 vol% D_(2)EHpA functionalized resin,pH=1.5 and an S/L ratio of 10 mg/mL The discharge of yttrium ions was done under the same conditions of extraction stage,using a 2 mol/L [H_(2)SO_(4)] as stripping *** to 80% yttrium is extracted,while 75% yttrium is recovered in the striping *** all experiments,the reaction equilibrium is reached after 20 min,and the kinetics for the extraction stage was determined as a second-order ***,experiments were carried out to discharge the yttriumloaded resins,and it has been determined that the best pH value to strip the Y ions is *** tests of extraction and discharge for yttrium ions show that the functionalized resin can work at least five cycles without decreasing its ***,the proposed process was tested in a real solution with Y ions fro m a waste fluorescent la mp powder leached in H_(2)SO_(4),demonstrating the ability to effectively recover yttrium,separating it from various metals from the studied residue.

关键词： Yttrium recovery Rare earth solid-liquid extraction XAD-7 resin fluorescent lamps recycling Solid-liquid kinetics extraction