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Phosphine/Benzocyclone-based Neutral Nickel Catalysts for Ethylene Polymerization and Copolymerization with Polar Monomers

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chinese Journal of Polymer Science 2024年第2期42卷 202-212,I0007页

作者： Fei wang Li Pan Vladislav A.Tuskaev Svetlana ch.Gagieva Yue-Sheng Li Tianjin Key Lab of Composite&Functional Materials School of Material Science and EngineeringTianjin UniversityTianjin300072China Department of chemistry Lomonosov Moscow State UniversityRussian Federation InstitutionLeninskie Gory 1Moscow119991Russian Federation A N Nesmeyanov institute of Organoelement Compounds Russian Academy of SciencesVavilova st.28Moscow119991Russian Federation

The efficient copolymerization of olefin with polar monomers using nickel-based catalysts presents a longstanding challenge. in this contribution, three phosphine-benzocyclone ligands and corresponding neutral nickel catalysts(Ni1: Ar = Ph;Ni2: Ar = 2-(C_(6)H_(5))C_(6)H_(4);Ni3: Ar = 2-[2',6'-(Me O)_(2)-C_(6)H3]C_(6)H_(4)) were prepared and applied for the ethylene polymerization and copolymerization with polar monomers without any cocatalyst. The bulky substituent groups in complexes Ni2 and Ni3 contributed to high catalytic activities(up to 7.24×10^(6) and 9.04×10^(6)g·mol Ni^(-1)·h^(-1), respectively), and produced high-molecular-weight polyethylene(Mw up to 545.7 k Da). Complex Ni3 exhibited high activities for ethylene polymerization at the level of 10^(6) g·mol Ni^(-1)·h^(-1) across a wide range from 30 ℃ to 120 ℃, exhibiting excellent high temperature tolerance. These nickel complexes were also effectively employed in the copolymerization of ethylene with methyl acrylate, ethyl acrylate, butyl acrylate and lauryl acrylate, producing copolymers with high molecular weights(Mw up to 80.5 k Da) and high polar monomer incorporation(up to 8.2 mol%). Microstructure analyses revealed that the introduction of large sterically hindered substituents facilitated the incorporation of polar functional units into the polymer backbone. This study demonstrates the potential of these nickel-based catalysts for efficient copolymerization of olefin with polar monomers.

关键词： Neutral nickel catalyst Ethylene polymerization Copolymerization Polar acrylate monomers

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Geochemistry and mineral chemistry of the armoor granitoids,eastern dharwar craton: implications for the redox conditions and tectono-magmatic environment

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Acta Geochimica 2024年第1期43卷 110-133页

作者： A.Ajay Kumar ch.Ashok Department of Geology Osmania UniversityHyderabad 500007India CSiR-National Geophysical Research institute UppalHyderabad 500007India

The mineralogical and geochemical characteristics of the K-rich granites from the Armoor granitic rocks in the northeastern portion of the Eastern Dharwar Craton(EDC) are *** order to understand its physicochemical conditions,the petrogenesis of the granitoid was explained from biotite chemistry and geochemical *** of mineral chemistry expose that compositionally,K-feldspar and plagioclase in Armoor granite rocks range from An0,Ab_(3-5.9),Or_(94-96.9) and An_(5-29,-Ab71.9-94.9),Or_(0-1.5),*** mineral chemistry of biotite crystals exhibits composition that varies from primary to re-equilibrated primary *** biotites from the Armoor granites generally exhibit an i-type trend,with calc-alkaline parental magma in a subduction *** chemistry of granites displays magnetite(oxidized)series nature,which has oxygen fugacity(fO_(2))=-15.1 to-16.7(log_(10) bar),under high oxidizing *** and pressure estimates for the crystallization of Armoor granites based on biotite composition are T=612-716 ℃ and 1.0-0.4 kbar,***,these rocks are metaluminous to slightly peraluminous and magnesian,with calc-alkaline potassiumrich *** the chondrite normalized REE diagram,the granites have positive europium anomalies;rich Sr/Y,(Dy/Yb)_(N) ratios and reduced Mg#,Rb/Sr,Rb,Sr indicate that the melting of earlier rocks,crystal accumulation and residual garnet source formed at high *** examined granites show that they are produced from the melting of crustal ***,the extensive analyses of the described Armoor granite suggest that they were produced by crust sources and developed under oxidizing conditions in subduction setting.

关键词： Armoor granites Oxygen fugacity Crystal accumulation Remelting Subduction

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Continuous ward monitoring and intensive postoperative management

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chinese Medical Journal 2024年第6期137卷 631-632页

作者： Kai Li Jiayi wang Daniel i.Sessler Department of Anesthesiology China-Japan Union HospitalJilin UniversityChangchunJilin 130031China Outcomes Research Consortium ClevelandOhio 44195USA Department of Anesthesiology Shanghai Ninth People’s HospitalShanghai JiaoTong University School of MedicineShanghai 201999China Department of Outcomes Research Cleveland ClinicClevelandOhio 44195USA

When patients having major surgery reach the post-anaesthesia care unit,families naturally assume that they have survived the most dangerous part of the perioperative *** assumption is *** in the 30 days after surgery is 140 times higher than intraoperative mortality.^([1,2])in fact,if the month after surgery were considered a disease,it would be the world’s third leading cause of death.^([3])

关键词： assume dangerous wrong

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Data-driven modeling on anisotropic mechanical behavior of brain tissue with internal pressure

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Defence Technology（防务技术） 2024年第3期33卷 55-65页

作者： Zhiyuan Tang Yu wang Khalil i.Elkhodary Zefeng Yu Shan Tang Dan Peng State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentDalian University of Technology116023DalianPR China The Department of Mechanical Engineering The American University in CairoNew Cairo11835Egypt Department of Neurology The Second Hospital of Dalian Medical UniversityDalian116023PR China

Brain tissue is one of the softest parts of the human body,composed of white matter and grey *** mechanical behavior of the brain tissue plays an essential role in regulating brain morphology and brain ***,traumatic brain injury(TBi)and various brain diseases are also greatly influenced by the brain's mechanical *** white matter or grey matter,brain tissue contains multiscale structures composed of neurons,glial cells,fibers,blood vessels,etc.,each with different mechanical *** such,brain tissue exhibits complex mechanical behavior,usually with strong nonlinearity,heterogeneity,and directional *** a constitutive law for multiscale brain tissue using traditional function-based approaches can be very ***,this paper proposes a data-driven approach to establish the desired mechanical model of brain *** focus on blood vessels with internal pressure embedded in a white or grey matter matrix material to demonstrate our *** matrix is described by an isotropic or anisotropic nonlinear elastic model.A representative unit cell(RUC)with blood vessels is built,which is used to generate the stress-strain data under different internal blood pressure and various proportional displacement loading *** generated stress-strain data is then used to train a mechanical law using artificial neural networks to predict the macroscopic mechanical response of brain tissue under different internal ***,the trained material model is implemented into finite element software to predict the mechanical behavior of a whole brain under intracranial pressure and distributed body *** with a direct numerical simulation that employs a reference material model,our proposed approach greatly reduces the computational cost and improves modeling *** predictions made by our trained model demonstrate sufficient ***,we find that the level of internal blood pressur

关键词： Data driven Constitutive law Anisotropy Brain tissue internal pressure

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Bile acids,gut microbiota,and therapeutic insights in hepatocellular carcinoma

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Cancer Biology & Medicine 2024年第2期21卷 144-162页

作者： Yang Song Harry ch Lau Xiang Zhang Jun Yu institute of Digestive Disease and Department of Medicine and Therapeutics State Key Laboratory of Digestive DiseaseLi Ka Shing Institute of Health SciencesCUHK Shenzhen Research InstituteThe Chinese University of Hong KongHong KongChina Department of Gastroenterology Zhongshan Hospital Xiamen UniversityXiamen 361004China

Hepatocellular carcinoma(HCC)is a prevalent and aggressive liver *** interplay between bile acids(BAs)and the gut microbiota has emerged as a critical factor in HCC development and *** normal conditions,BA metabolism is tightly regulated through a bidirectional interplay between gut microorganisms and *** gut microbiota plays a critical role in BA metabolism,and BAs are endogenous signaling molecules that help maintain liver and intestinal *** note,dysbiotic changes in the gut microbiota during pathogenesis and cancer development can disrupt BA homeostasis,thereby leading to liver inflammation and fibrosis,and ultimately contributing to HCC ***,understanding the intricate interplay between BAs and the gut microbiota is crucial for elucidating the mechanisms underlying *** this review,we comprehensively explore the roles and functions of BA metabolism,with a focus on the interactions between BAs and gut microorganisms in ***,therapeutic strategies targeting BA metabolism and the gut microbiota are discussed,including the use of BA agonists/antagonists,probiotic/prebiotic and dietary interventions,fecal microbiota transplantation,and engineered *** summary,understanding the complex BA-microbiota crosstalk can provide valuable insights into HCC development and facilitate the development of innovative therapeutic approaches for liver malignancy.

关键词： Bile acid gut microbiota hepatocellular carcinoma therapeutics microbiota modulation

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A core-satellite self-assembled SERS aptasensor containing a“biological-silent region”Raman tag for the accurate and ultrasensitive detection of histamine

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Food Science and Human Wellness 2024年第2期13卷 1029-1039页

作者： chen chen Yingfang Zhang Ximo wang Xuguang Qiao Geoffrey i.N.Waterhouse Zhixiang Xu Key Laboratory of Food Processing Technology and Quality Control in Shandong Province College of Food Science and EngineeringShandong Agricultural UniversityTai’an 271018China School of chemical Sciences The University of AucklandAuckland 1142New Zealand

Herein,a novel interference-free surface-enhanced Raman spectroscopy(SERS)strategy based on magnetic nanoparticles(MNPs)and aptamer-driven assemblies was proposed for the ultrasensitive detection of histamine.A core-satellite SERS aptasensor was constructed by combining aptamer-decorated Fe_(3)O_(4)@Au MNPs(as the recognize probe for histamine)and complementary DNA-modified silver nanoparticles carrying 4-mercaptobenzonitrile(4-MBN)(Ag@4-MBN@Ag-c-DNA)as the SERS signal probe for the indirect detection of *** an applied magnetic field in the absence of histamine,the assembly gave an intense Raman signal at“Raman biological-silent”region due to *** the presence of histamine,the Ag@4-MBN@Ag-c-DNA SERS-tag was released from the Fe_(3)O_(4)@Au MNPs,thus decreasing the SERS *** optimal conditions,an ultra-low limit of detection of 0.65×10^(-3)ng/mL and a linear range 10^(-2)-10^5 ng/mL on the SERS aptasensor were *** histamine content in four food samples were analyzed using the SERS aptasensor,with the results consistent with those determined by high performance liquid *** present work highlights the merits of indirect strategies for the ultrasensitive and highly selective SERS detection of small biological molecules in complex matrices.

关键词： Surface-enhanced Raman spectroscopy Raman biological-silent region Aptamer Histamine detection Universal SERS-tag

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Trends in mortality among the geriatric population undergoing Surgical aortic valve replacement (SAVR) and potential racial disparities: a 20-year perspective via the National (Nationwide) inpatient Sample

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Journal of Geriatric Cardiology 2024年第7期21卷 716-722页

作者： Nomesh Kumar Kamleshun Ramphul FNU Bawna Nitish Behary Paray Mansimran Si-ngh Dulay Jasninder Singh Dhaliwal Shruti Aggarwal Sebastian Mactaggart Suma Sri chennapragada Shaheen Sombans Renuka Verma Hemamalini Sakthivel Raheel Ahmed Department of internal Medicine Detroit Medical Center Sinai Grace-Wayne State UniversityMichiganUSA in-dependent Researcher TrioletMauritius independent researcher Farmington HillsMichiganUSA Royal Devon University Healthcare NHS Foundation Trust ExeterUnited Kingdom Royal Brompton Hospital part of Guy’s and St.Thomas’NHS Foundation TrustLondonUnited Kingdom Department of internal Medicine University of Cali-forniaRiversideUSA independent Researcher New DelhiIndia Northumbria Hospitals NHS Foundation Trust NewcastleUnited Kingdom Department of internal Medicine Louisiana State UniversityShreveportUSA Sha-heen Sombans Independent ResearcherHyderabadIndia Department of internal Medicine Kirk Kerkorian School of Medicine at UNLVLas VegasUSA One Brooklyn Health System/interfaith Medical Ctr Program BrooklynNYUSA

ed data from the National(Nationwide)inpatient Sample over a 20-year period from 2001 to 2020 using specific iCD-9 and iCD-10 *** included patients aged≥60 and≤80 years with races recorded as White,African American,or Hispanic at the time of their hospitalization for *** analyzed and reported the baseline characteristics,risk-adjusted in-mortality,and complications stratified by *** Results Of 420,181 patients studied,90.0%identified as White,4.0%as African American and 6.0%as *** a de-crease in overall in-hospital mortality rates from 3.8%between 2001-2005 to 1.8%between 2016-2020,African Americans had higher odds of all-cause in-hospital deaths compared to Whites(aOR=1.390,Pitionally,they were more likely to experi-ence cardiogenic shock(aOR=1.241,Pidney injury(aOR=1.314,Pikely to require organ support such as iABP use(aOR=1.336,Pinvasive mechanical ventilation(aOR=1.342,Pinterestingly,Americans were less likely to report events of acute ischemic stroke compared to Whites(aOR=0.852,Pican Conclusions Despite a reassuring reduction in overall in-hospital mortality rates of geriatric patients undergoing SAVR for aor-tic stenosis,racial disparities in health outcomes remain pervasive with minorities more likely to report higher in-hospital mor-bidity and mortality.

关键词： mortality likely spite

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Ballistic design and testing of a composite armour reinforced by CNTs suitable for armoured vehicles

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Defence Technology（防务技术） 2024年第2期32卷 173-195页

作者： Evangelos ch.Tsirogiannis Evangelos Daskalakis Mohamed H.Hassan Abdalla M.Omar Paulo Bartolo EODH SA Research and Development DepartmentLakkoma Chalkidikis63080Greece School of Mechanical Aerospace and Civil EngineeringUniversity of ManchesterManchesterM139PLUK Singapore Centre for 3D Printing School of Mechanical and Aerospace EngineeringNanyang Technological University639798Singapore

This paper is investigating the use of composite armour reinforced by nanomaterials, for the protection of light armoured(LAV) and medium armoured military vehicles(MAV), and the interaction between the composite materials and high-performance ballistic projectiles. Four armour materials, consisted of front hybrid fibre reinforced polymer cover layer, ceramic strike-face, fibre reinforced polymer intermediate layer and the metal matrix composite reinforced backplate, were manufactured and assembled by adhesive technology. The proposed laminated protection system is suitable for armoured ground vehicles;however, it could be used as armour on ground, air and naval platforms. The design of the protection system, including material selection and thickness, was elaborated depending on the performance requirements of Level 4 + STANAG 4569 military standard(projectile 14.5 mm × 114 mm APi B32) and especially on a design philosophy which is analysed with the specifications. The backplate of this new composite is a hybrid material of Metal Matrix Composite(MMC) reinforced with carbon nanotubes(CNTs), manufactured with the use of powder metallurgy technique. The composite backplate material was morphologically, mechanically and chemically analysed. Results show that all plates are presenting high mechanical properties and ballistic characteristics, compared to commonly used armour plates. Real military ballistic tests according to AEP-STANAG 4569 were carried out for the total composite armour systems. After the ballistic tests, AA2024-CNT3 showed the best protection results, compared with the other plates(AA2024-CNT1 and AA2024-CNT2), with the projectile being unable to fully penetrate the composite plate.

关键词： Passive armour protection Protective armour Ballistic performance Hybrid composites Vehicle protection

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Phylogenetic placement of bizarre karschiellid earwigs

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insect Science 2024年第3期31卷 989-992页

作者： Petr Kocárek ivona Horká Vojtěch Bonczek Markéta Kirstová Department of Biology and Ecology University of OstravaOstravaCzech Republic

Dear Editor,Karschiellidae are a mysterious group of earwigs that attract attention not only because of their interesting appearance and unexplained way of life but also mainly due to their unclear *** phylogenetic relationships of karschiellids remain speculative even 120 years since the family was described,above all due to the unavailability of DNA-grade material for molecular phylogenetic *** study includes successfully sequenced representatives of the Karschiellidae for the first time,and a probable evolutionary scheme and natural classification of karschiellids are proposed based on the constructed multigene phylogeny.

关键词： classification. phylogeny evolutionary

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The reformation of catalyst:From a trial-and-error synthesis to rational design

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Nano Research 2024年第4期17卷 3261-3301页

作者： Ligang wang Jiabin Wu Shunwu wang Huan Liu Yao wang Dingsheng wang Department of chemistry Tsinghua UniversityBeijing 100084China

The appropriate catalysts can accelerate the reaction rate and effectively boost the efficient conversion of various molecules,which is of great importance in the study of chemistry,chemical industry,energy,materials and environmental ***,efficient,environmentally friendly,and easy to operate synthesis methods have been used to prepare various types of *** previous studies have reported the synthesis and characterization of the aforementioned catalysts,more still remain in trial and error methods,without in-depth consideration and improvement of traditional synthesis ***,we comprehensively summarize and compare the preparation methods of the trial-and-error synthesis strategy,structure–activity relationships and density functional theory(DFT)guided catalysts rational design for nanomaterials and atomically dispersed *** also discuss in detail the utilization of the nanomaterials and single atom catalysts for converting small molecules(H_(2)O,O_(2),CO_(2),N_(2),etc.)into value-added products driven by electrocatalysis,photocatalysis,and ***,the challenges and outlooks of mass preparation and production of efficient and green catalysts through conventional trial and error synthesis and DFT theory are featured in accordance with its current development.

关键词： trial-and-error synthesis structure–activity relationships density functional theory(DFT)guidance nanomaterials atomically dispersed catalysts

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