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Olefin polymerization Behavior of Titanium(Iv) Complexes with Fluorinated and Non-fluorinated Aliphatic phenoxyimine Ligands

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Chinese Journal of polymer Science 2024年第1期42卷 52-62,I0007页

作者： vladislav A.Tuskaev kasim F.Magomedov Svetlana Ch.Gagieva dmitry A.kurmaev Yulia v.Nelyubina Evgenii k.Golubev Maria d.Evseeva viktor G.vasil'ev Galina G.Nikiforova Mikhail I.Buzin vyacheslav S.Bogdanov Boris M.Bulychev department of Chemistry M.V.Lomonosov Moscow State UniversityMoscow 119992Russian Federation A.N.Nesmeyanov Institute of Organoelement Compounds Russian Academy of SciencesMoscow119991Russian Federation Enikolopov Institute of Synthetic polymer Materials Russian Academy of SciencesMoscow 117393Russian Federation

A series of Ti(Ⅳ) dichloride and dialkoxide com plexes with phenoxyimine ligands containing fluorinated and nonfluorinated aliphatic imine fragments have been *** molecular structures of complexes 1 and 4 were established by single-crystal X-ray diffraction *** complexes adopt a distorted octahedral coordination structure around the titanium atom and two oxygen atoms are situated in trans position while two nitrogen atoms and two outgoing ligands(Cl or iprO) are situated in cis *** of activators(MMAO-12 and combinations Et_nAICl_(3-n)+Bu_(2)Mg) and outgoing ligand(Cl or iprO) nature on the catalytic activity and properties of the resulting polymers was *** Ti complexes,despite the nature of the outgoing ligands(Cl or iprO) in the presence of Al/Mg activators,was found to display a high ethylene polymerization activity in the range 1600-3830 kg_(polymer)·mol_(Ti)^(-1)·h^(-1)·atm^(-1) with a viscosity average molecular weight(M_v) value in the range 1.1×10~6-7.1×10~6 dalton(da).The resulting UHMWpE can be processed by a solventless method into high-strength and high-modulus oriented *** rheological characteristics of a polymer melt have been *** absence of a cross-over point did not allow to compare the values of the molecular weight distribution of polymers obtained on fluorinated and non-fluorinated pre-catalysts,however,the estimation of the entanglement density is in good agreement with the mechanical characteristics of oriented film *** activation with methylalumoxane,the activity of the com plexes decreased very significantly;however,a polymer with a molecular weight of about 12 million da was *** the process of ethylene/octene-1 copolymerization,fluorine-containing precatalysts showed a clear advantage over non-fluorinated analogues both in activity and in comonomer content.

关键词： FI catalysts Titanium(Iv) (Co)polymerization Al/Mg co-catalyst Ultra-high molecular weight polyethylene

Gradient-induced long-range optical pulling force based on photonic band gap

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Light(Science & Applications) 2024年第5期13卷 865-874页

作者： Wenlong Lu Alexey v.krasavin Sheng Lan Anatoly v.Zayats Qiaofeng dai Guangdong Basic Research Center of Excellence for Structure and Fundamental Interactions of Matter Guangdong Provincial Key Laboratory of Nanophotonic Functional Materials and DevicesSchool of Information and Optoelectronic Science and EngineeringSouth China Normal UniversityGuangzhou 510006China department of physics and London Centre for Nanotechnology King’s College LondonLondon WC2R 2LSUK

Optical pulling provides a new degree of freedom in optical *** is generally believed that long-range optical pulling forces cannot be generated by the gradient of the incident ***,we theoretically propose and numerically demonstrate the realization of a long-range optical pulling force stemming from a self-induced gradient field in the manipulated *** analogy to potential barriers in quantum tunnelling,we use a photonic band gap design in order to obtain the intensity gradients inside a manipulated object placed in a photonic crystal waveguide,thereby achieving a pulling *** the usual scattering-type optical pulling forces,the proposed gradient-field approach does not require precise elimination of the reflection from the manipulated *** particular,the Einstein-Laub formalism is applied to design this unconventional gradient *** magnitude of the force can be enhanced by a factor of up to 50 at the optical resonance of the manipulated object in the waveguide,making it insensitive to *** developed approach helps to break the limitation of scattering forces to obtain longrange optical pulling for manipulation and sorting of nanoparticles and other *** developed principle of using the band gap to obtain a pulling force may also be applied to other types of waves,such as acoustic or water waves,which are important for numerous applications.

关键词： optical waveguide scattering

palliative long-term abdominal drains vs large volume paracenteses for the management of refractory ascites in end-stage liver disease

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World Journal of Hepatology 2024年第3期16卷 428-438页

作者： Senamjit kaur Rodrigo v Motta Bryony Chapman victoria Wharton Jane d Collier Francesca Saffioti Oxford Liver Unit Department of Gastroenterology and HepatologyOxford University Hospitals NHS Foundation TrustOxford OX39DUUnited Kingdom Oxford Liver Unit and Translational Gastroenterology Unit Nuffield Department of MedicineUniversity of OxfordOxford OX39DUUnited Kingdom

BACkGROUNd Long-term abdominal drains(LTAd)are a cost-effective palliative measure to manage malignant ascites in the community,but their use in patients with end-stage chronic liver disease and refractory ascites is not routine *** safety and cost-effectiveness of LTAd are currently being studied in this setting,with preliminary positive *** hypothesised that palliative LTAd are as effective and safe as repeat palliative large volume paracentesis(Lvp)in patients with cirrhosis and refractory ascites and may offer advantages in patients’quality of *** To compare the effectiveness and safety of palliative LTAd and Lvp in refractory ascites secondary to end-stage chronic liver *** A retrospective,observational cohort study comparing the effectiveness and safety outcomes of palliative LTAd and regular palliative Lvp as a treatment for refractory ascites in consecutive patients with end-stage chronic liver disease followed-up at our United kingdom tertiary centre between 2018 and 2022 was ***’s exact tests and the Mann-Whitney U test were used to compare qualitative and quantitative variables,***-Meier survival estimates were generated to stratify time-related outcomes according to the type of *** Thirty patients had a total of 35 indwelling abdominal drains and nineteen patients underwent regular *** baseline characteristics were similar between the *** antibiotics were more frequently prescribed in patients with LTAd(p=0.012),while the incidence of peritonitis did not differ between the two groups(p=0.46).The incidence of acute kidney injury(p=0.014)and ascites/drain-related hospital admissions(p=0.004)were significantly higher in the Lvp *** overall survival was similar in the two groups(log-rank p=0.26),but the endpoint-free survival was significantly shorter in the Lvp group(p=0.003,pp=0.018 for first ascites/drain-related admission,acute kidney injury and drain

关键词： decompensated liver cirrhosis Indwelling abdominal catheter Rocket drain palliative care Safety Quality of life

Laboratory evaluation of toxicity of selected insecticides against egg and larval stages of cotton pink bollworm, pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae)

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Journal of Cotton Research 2024年第1期7卷 15-28页

作者： BUSNOOR Abhishek v. WAdASkAR R.M. FANd Babasaheb B. TAMBE v.J. pILLAI T. MAHULE d.J. NAGRARE v.S. pRASAd Y.G. Entomology Section College of Agriculture(Dr.Panjabrao Deshmukh Krishi Vidyapeeth)Nagpur 440001MaharashtraIndia Indian Council of Agricultural Research-Central Institute for Cotton Research Nagpur 441108MaharashtraIndia

Background The cryptic nature of pink bollworm pectinophora gossypiella(Saunders)larvae enables its reduced vul-nerability to insecticidal ***,the development of resistance against Bacillus thuringiensis(Bt)toxins posed a serious threat to transgenic cotton *** necessitated determining the critical timing of spray applications on the control *** study assessed the influence of egg age(freshly laid ***-day-old)and the loca-tion of larvae(directly exposed to the insecticide residues on the boll rind *** inside the bolls)on insecticide control *** The results revealed a significant decrease in the ovicidal activity of tested insecticides with an increase in the age of eggs from one day old to three days old(paired t-test,pvae directly exposed to the insec-ticide residues on the boll rind were more susceptible(>80%mortality)than the larvae exposed after they had bur-rowed inside the bolls(d insecticides on developmental biology were more pronounced in the experiment on pre-larval release insecticide treatment compared with insecticide treatment given post-larval release and entry inside the *** Egg age influences the insecticide susceptibility,as does the larval location,directly exposed vs bur-rowed inside the *** eggs and the larvae that had burrowed inside the green bolls of cotton were relatively less susceptible to the insecticide *** toxic effects of insecticides on egg and larval stages were primar-ily *** findings are significant for devising a comprehensive strategy for pink bollworm management on a sustainable basis.

关键词： Bioefficacy Cotton Insecticides pink bollworm pectinophora gossypiella Timings of spray

plasma electrolytic formation and characterization of MnWO_(4)/WO_(3) film heterostructures

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ChemphysMater 2024年第3期3卷 293-302页

作者： M.S.vasilyeva I.v.Lukiyanchuk Yu.B.Budnikova v.G.kuryavyi d.H.Shlyk G.A.Zverev department of Chemistry and Materials of Institute of High Technology and Advanced Materials Far Eastern Federal UniversityFEFU CampusVladivostok 690922Russia Institute of Chemistry Far Eastern BranchRussian Academy of SciencesVladivostok 690022Russia

MnWO_(4)/WO_(3) p-n heterojunction films were fabricated using a one-step method consisting of the plasma electrolytic oxidation(pEO)of titanium in homogeneous electrolytes containing paratungstate ions and stable watersoluble EdTA-chelated *** influences of the formation current density and W:Mn molar ratio of the electrolyte,which was varied from 1:2 to 2:1,on the composition,morphology,and optical and photocatalytic properties of the resulting coatings were studied.X-ray diffraction analysis,scanning electron microscopy,energy dispersive X-ray analysis,Raman spectroscopy,and ultraviolet diffuse reflectance spectroscopy were used to characterize the formed *** of the W:Mn ratio of the electrolyte,the coatings contained crystalline t-WO_(3) and m-MnWO_(4).depending on the formation conditions,the optical band gap energies of the composites varied from 2.63 to 3.01 *** largest absorption red shift and lowest band gap energy were observed in the film composite formed in an electrolyte with W:Mn=2:1,at a current density of 0.2 A cm^(−2).Composites obtained in electrolytes with W:Mn ratios of 2:1 and 1:1 exhibited photocatalytic activity in the degradation of rhodamine C and methyl orange dyes in the presence of 10 mmol L^(–1) H2O_(2) under ultraviolet and visible light *** role of hydrogen peroxide in this dye degradation on pEO-coated composites under light irradiation is discussed.

关键词： plasma electrolytic oxidation Manganese tungstate Tungsten oxide Titanium Optical properties p-n heterojunction

Expanded porphyrin Exhibiting Off-Centered Out-of-plane Coordination to dysprosium

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CCS Chemistry 2024年第7期6卷 1731-1738页

作者： dmitry I.Nazarov Jorge Labella Alexey v.kuzmin Maxim A.Faraonov Evgenii N.Ivanov Salavat S.khasanov Tomas Torres Mikhail k.Islyaikin dmitri v.konarev Federal Research Center of problems of Chemical physics and Medicinal Chemistry RAS 142432 Chernogolovka department of Organic Chemistry Universidad Autonoma de Madrid28049 Madrid Institute of Solid-State physics RAS 142432 Chernogolovka Research Institute of Macroheterocycles Ivanovo State University of Chemistry and Technology15300 Ivanovo G.A.krestov Institute of Solution Chemistry of the Russian Academy of Sciences 153045 Ivanovo Institute for Advanced Research in Chemical Sciences Universidad Autonoma de Madrid28049 Madrid IMdEA-Nanociencia 28049 Madrid

The complexation of high-spin lanthanides to porphyrinoids is a powerful strategy for the development of advanced molecular *** this context,the use of expanded porphyrinoids remains elusive since their coordination chemistry is challenging to ***,taking inspiration from on-surface chemistry,we explored the coordination of dy^(3+)to a six-membered porphyrinoid,namely,the hemihexaphyrazine ***,we observed the selective formation of a mono-nuclear off-centered,out-of-plane H_(2)Hhp-dy^(3+)complex when performing the complexation under reductive *** this reaction,the oxidation state of the macrocycle did not *** X-ray diffraction analysis,we found that the coordination number of dy in this complex was *** macrocycle cocrystallized with decamethylcobaltocene(Cp_(2)^(*)Co)molecules,giving rise to a wellordered solid-state packing,governed byπ-π*** a result of this organization,a small magnetic coupling between the neighboring molecules was *** in all,this work provides key insights into the coordination of magnetically active metals with expanded porphyrinoids,thus motivating the development of advanced spintronic devices.

关键词： porphyrins dysprosium macrocycle coordination chemistry magnetism

pd-1^(+)and TIM-3^(+)T cells widely express commonγ-chain cytokine receptors in multiple myeloma patients,and IL-2,IL-7,IL-15 stimulation up-regulates pd-1 and TIM-3 on T cells

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Oncology Research 2024年第10期32卷 1575-1587页

作者： EGOR v.BATOROv ALISA d.INESHINA TATIANA A.ARISTOvA vERA v.dENISOvA SvETLANA A.SIZIkOvA dARIA S.BATOROvA GALINA Y.USHAkOvA EkATERINA Y.SHEvELA ELENA R.CHERNYkH Laboratory of Cellular Immunotherapy Research Institute of Fundamental and Clinical ImmunologyNovosibirsk630099Russia v.Zelman Institute of Medicine and psychology Novosibirsk National Research State UniversityNovosibirsk630090Russia department of Hematology and Bone Marrow Transplantation Research Institute of Fundamental and Clinical ImmunologyNovosibirsk630099Russia

Background:Immune checkpoint ligand-receptor interactions appear to be associated with multiple myeloma(MM)***,previous studies showed the possibility of pd-1 and TIM-3 expression on T cells upon stimulation with commonγ-chain family cytokines in vitro and during homeostatic *** aim of the present work was to study the impact of homeostatic proliferation on the expansion of certain T cell subsets upregulating pd-1 and TIM-3 checkpoint ***:The expression of Cd25,Cd122,Cd127 commonγ-chain cytokine receptors,phosphorylated signal transducer and activator of transcription-5(pSTAT5)and eomesodermin(EOMES)was comparatively assessed with flow cytometry in pd-1-and TIM-3-negative and positive T cells before the conditioning and during the first post-transplant month in peripheral blood samples of MM ***:Substantial proportions of pd-1-and TIM-3-positive T lymphocytes expressed commonγ-chain cytokine receptors and *** of cytokine receptor expressing cells were significantly higher within TIM-3+T cells compared to pd-1+TIM-3−*** proportions of both pd-1-/TIM-3-negative and positive Cd8+T cells express EOMES,while only moderate frequencies of Cd4+pd-1+/TIM-3+T cells up-regulate this transcription ***,the surface presence of Cd25 and intranuclear expression of EOMES in Cd4+T cells were mutually exclusive regardless of pd-1 and TIM-3 *** stimulation with commonγ-chain cytokines up-regulates pd-1 and TIM-3 during the proliferation of initially pd-1/TIM-3-negative T cells but fails to expand initially pd-1+and TIM-3+T cell subsets in ***:Both pd-1 and TIM-3 expressing T cells appear to be able to respond to homeostatic cytokine *** in commonγ-chain cytokine receptor expression between pd-1+and TIM-3+T cells may reflect functional dissimilarity of these cell *** blockade appears to alleviate lymphopenia-induced prolif

关键词： Autologous hematopoietic stem cell transplantation(AHSCT) Cd25 Cd122 Eomesodermin(EOMES) Homeostatic proliferation

Solar-driven CO_(2) conversion to methane and methanol using different nanostructured Cu_(2)O-based catalysts modified with Au nanoparticles

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Journal of Energy Chemistry 2024年第4期91卷 287-298页

作者： João Angelo Lima perini Lilian d.Moura Torquato Juliana Fde Brito Gustavo A.Andolpho Mateus A.Gonçalves Leonardo d.de Angelis Lucas d.Germano Susana I.Córdoba de Torresi Teodorico C.Ramalho Maria v.Boldrin Zanoni São paulo State University(UNESp) Institute of ChemistryRua Prof.Francisco Degni55AraraquaraSP 14800-060Brazil National Institute of Alternative Technologies for detection Toxicological Evaluation and Removal of Micropollutants and Radioactive Substances(INCT-DATREM)São Paulo State University(UNESP)Institute of ChemistryRua Prof.Francisco Degni55AraraquaraSP 14800-060Brazil Laboratory of Molecular Modelling Department of ChemistryNatural Sciences InstituteFederal University of LavrasLavrasMG 37200-900Brazil department of Chemistry Faculty of ScienceUniversity of Hradec KrálovéHradec Králové50003Czech Republic Instituto de Química Universidade de São PauloAv.Prof.Lineu Prestes 74805508-080São PauloSPBrazil

This work describes the use of TiO_(2)nanotubes-based electrodes(TNT)modified with Cu_(2)O nanostructures and gold nanoparticles for the photoelectroreduction of CO_(2)to produce value-added compounds.A thin layer of polydopamine was used as both an adherent agent and an electron transfer mediator,due to itsπ-conjugated electron *** highest production yield was achieved using a TNT@pdA/Nc/Au40%electrode,with Faradaic efficiencies of 47.4%(110.5μM cm^(-2))and 27.8%(50.4μM cm^(-2))for methanol and methane,*** performance of the photoelectrodes was shown to be Cu_(2)O facet-dependent,with cubic structures leading to greater conversion of CO_(2)to methanol(43%)and methane(27%),compared to the octahedral morphology,while a higher percentage of metallic gold on the nanostructured Cu_(2)O surface was mainly important for *** functional theory(dFT)calculations supported these findings,attributing the superior photoelectrocatalytic performance of the TNT@pdA/Nc/Au40%electrode for CH4generation to the formation of an OCH3intermediate bonded to Au *** using isotope-labeling and analysis by gas chromatograph-mass(GC-MS)demonstrated that13CO_(2)was the source for photoelectrocatalytic generation of13CH3OH and13CH313CH2OH.

关键词： Cu_(2)O nanocubes photoelectrocatalysis polydopamine CO_(2) photoelectroreduction dFT calculations

Quantum-mechanical effects in photoluminescence from thin crystalline gold films

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Light(Science & Applications) 2024年第4期13卷 783-794页

作者： Alan R.Bowman Alvaro Rodríguez Echarri Fatemeh kiani Fadil Iyikanat Ted v.Tsoulos Joel d.Cox Ravishankar Sundararaman F.Javier García de Abajo Giulia Tagliabue Laboratory of Nanoscience for Energy Technologies(LNET) STIÉcole Polytechnique Fédérale de Lausanne(EPFL)LausanneSwitzerland ICFO–Institut de Ciencies Fotoniques The Barcelona Institute of Science and TechnologyCastelldefels(Barcelona)Spain. MBI–Max-Born-Institut BerlinGermany. pOLIMA–Center for polariton-driven Light–Matter Interactions University of Southern DenmarkOdense MDenmark. danish Institute for Advanced Study University of Southern DenmarkOdense MDenmark. department of Materials Science&Engineering Rensselaer Polytechnic InstituteTroyNYUSA. department of physics Applied Physicsand AstronomyRensselaer Polytechnic InstituteTroyNYUSA. ICREA–Institucio Catalana de Recerca i Estudis Avancats BarcelonaSpain

Luminescence constitutes a unique source of insight into hot carrier processes in metals,including those in plasmonic nanostructures used for sensing and energy ***,being weak in nature,metal luminescence remains poorly understood,its microscopic origin strongly debated,and its potential for unraveling nanoscale carrier dynamics largely ***,we reveal quantum-mechanical effects in the luminescence emanating from thin monocrystalline gold ***,we present experimental evidence,supported by first-principles simulations,to demonstrate its photoluminescence origin(i.e.,radiative emission from electron/hole recombination)when exciting in the interband *** model allows us to identify changes to the measured gold luminescence due to quantum-mechanical effects as the gold film thickness is ***,such effects are observable in the luminescence signal from flakes up to 40 nm in thickness,associated with the out-of-plane discreteness of the electronic band structure near the Fermi *** qualitatively reproduce the observations with first-principles modeling,thus establishing a unified description of luminescence in gold monocrystalline flakes and enabling its widespread application as a probe of carrier dynamics and light-matter interactions in this *** study paves the way for future explorations of hot carriers and charge-transfer dynamics in a multitude of material systems.

关键词： luminescence quantum crystalline