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Chinese Journal of Polymer Science 2024年第11期 1793-1801页

作者： e.e.Kim T.O.ershova A.S.Belova D.A.Khanin e.V.Bashkova g.g.Nikiforova Yu.N.Kononevich A.A.Anisimov O.I.Shchegolikhina A.M.Muzafarov A.N.Nesmeyanov Institute of Organoelement Compounds Russian Academy of Sciences Tula State Lev Tolstoy Pedagogical University V.Topchiev Institute of Petrochemical Synthesis Russian Academy of Sciences Moscow Institute of Physics and Technology (National Research University) N.S.enikolopov Institute of Synthetic Polymeric Materials Russian Academy of Sciences

Nowadays organosilicon luminescent materials are of increasing interest due to the variety of their synthetic or modification techniques and application fields. Ladder polyphenylsilsesquioxanes(L-PPSQ) are a unique class of organosilicon polymers, which can be ideal matrices for the luminescent composites due to their high thermal stability, optical transparency and mechanical strength. In this work, new mechanically strong, heat-resistant, transparent and sensitive to ammonia vapor luminescent composite films based on L-PPSQ have been obtained. As the source of europium ions oligophenyleuropiumsiloxane was used, demonstrating perfect compatibility to the matrix due to the similar *** improve luminescent properties of the films, new organosilicon ligands were introduced into the composites and their influence on the properties of the materials was studied. Valuable properties of described composites may allow their further application as multifunctional coatings.

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hydroxyapatite composites with carbon allotropes:Preparation,properties,and applications

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Particuology 2024年第5期88卷 239-265页

作者： Boris I.Kharisov Oxana V.Kharissova Lucy T.gonzález Yolanda Peña Méndez Igor e.Uflyand Idalia gómez de la Fuente Universidad Autónoma de Nuevo León Ave.UniversidadCiudad UniversitariaSan Nicolás de los GarzaNuevo León 66455Mexico Tecnologico de Monterrey Escuela de Ingeniería y CienciasMonterreyNuevo Leon 64890Mexico Department of Chemistry Southern Federal UniversityRostov-on-DonRussia

hydroxyapatite(hA)and its composites with inorganic additives,dopants,and polymers is a rapidly developing branch in the materials *** particular,carbon allotropes are widely used in these composites being widely applied for medical *** a gap of insufficient generalization of recent achievements in the field of the hA/Carbon composites,in this review we present the state of the art of the field of hA composites and hybrids with classic carbon allotropes and *** composites are known for carbon nanotubes,nanofibers,graphene and its oxidized forms,as well as,in a lesser grade,for graphite,fullerenes,nanodiamonds,carbon nanofoams,*** composites can be fabricated by a variety of classic and less-common methods,such as co-precipitation(with or without ultrasonic treatment),CVD,hot isostatic pressing,hydrothermal,spark plasma sintering,biomimetic mineralization,thermal and plasma spray,electrochemical and electrophoretic deposition,self-assembling,3D printing,electrospinning,and lyophilisation,among *** of various synthesis techniques can be also carried out for composite *** or synthetic hA can be used as it is for further interaction with carbon allotropes or it can be first prepared and then reacted with carbon counterpart;similarly,carbon allotropes can be introduced into the interaction with hA directly or they can be first synthesized,in particular from *** biocompatible composites can be produced in the form of coatings,powders,and scaffolds and can additionally contain quantitative amounts of third phases,frequently natural or synthetic *** these composites,especially with O-containing functionalizing groups,hA disadvantages could be considerably decreased with simultaneous enhancement of mechanical properties,becoming similar to human bone,chemical stability and biocompatibility,as well as possessing antibacterial ***→g reduction and higher hA decoration were obs

关键词： hydroxyapatite Carbon nanotubes graphene Quantum dots Fullerenes Nanodiamonds

genomics-driven derivatization of the bioactive fungal sesterterpenoid variecolin:Creation of an unnatural analogue with improved anticancer properties

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Acta Pharmaceutica Sinica B 2024年第1期14卷 421-432页

作者： Dexiu Yan Jemma Arakelyan Teng Wan Ritvik Raina Tsz Ki Chan Dohyun Ahn Vladimir Kushnarev Tsz Kiu Cheung ho Ching Chan Inseo Choi Pui Yi ho Feijun hu Yujeong Kim hill lam Lau Ying Lo Law Chi Seng Leung Chun Yin Tong Kai Kap Wong Wing lam Yim Nikolay S.Karnaukhov Richard Y.C.Kong Maria V.Babak Yudai Matsuda Department of Chemistry City University of Hong KongHong Kong SARChina igeM Team“VarieCure” City University of Hong KongHong Kong SARChina Department of Biomedical engineering City University of Hong KongHong Kong SARChina Moscow Clinical Research Center Named After A.S.Loginov Moscow 111123Russian Federation

A biosynthetic gene cluster for the bioactive fungal sesterterpenoids variecolin(1)and variecolactone(2)was identified in Aspergillus aculeatus ATCC *** production of 1 and 2 was achieved in Aspergillus oryzae by expressing the sesterterpene synthase VrcA and the cytochrome P450 ***,the replacement of VrcB with homologous P450s from other fungal terpenoid pathways yielded three new variecolin analogues(5-7).Analysis of the compounds’anticancer activity in vitro and in vivo revealed that although 5 and 1 had comparable activities,5 was associated with significantly reduced toxic side effects in cancer-bearing mice,indicating its potentially broader therapeutic *** study describes the first tests of variecolin and its analogues in animals and demonstrates the utility of synthetic biology for creating molecules with improved biological activities.

关键词： Animal studies Anticancer properties Biosynthesis Natural products Sesterterpenoids Synthetic biology Terpene synthases Variecolin

A Preliminary Comparative Study on the Centering Algorithms for CassiniISS NAC Images

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Research in Astronomy and Astrophysics 2024年第10期24卷 58-65页

作者： T.Liang Q.-F.Zhang g.-M.Liu W.-h.Zhu C.-S.Wang Department of Computer Science Jinan UniversityGuangzhou 510632China Sino-French Joint Laboratory for Astrometry Dynamics and Space ScienceJinan UniversityGuangzhou 510632China School of Computer Science Guangdong University of EducationGuangzhou 510303China

Obtaining high precision is an important consideration for astrometric studies using images from the Narrow Angle Camera(NAC)of the Cassini Imaging Science Subsystem(ISS).Selecting the best centering algorithm is key to enhancing astrometric *** this study,we compared the accuracy of five centering algorithms:gaussian fitting,the modified moments method,and three point-spread function(PSF)fitting methods(effective PSF(ePSF),PSFex,and extended PSF(x PSF)from the Cassini Imaging Central Laboratory for Operations(CICLOPS)).We assessed these algorithms using 70 ISS NAC star field images taken with CL1 and CL2 filters across different stellar *** ePSF method consistently demonstrated the highest accuracy,achieving precision below 0.03 pixels for stars of magnitude *** to the previously considered best,the modified moments method,the e PSF method improved overall accuracy by about 10%and 21%in the sample and line directions,***,the xPSF model provided by CICLOPS had lower precision than the ***,the ePSF exhibits an improvement in measurement precision of 23%and 17%in the sample and line directions,respectively,over the *** discrepancy might be attributed to the xPSF focusing on photometry rather than *** findings highlight the necessity of constructing PSF models specifically tailored for astrometric purposes in NAC images and provide guidance for enhancing astrometric measurements using these ISS NAC images.

关键词： methods:analytical techniques:image processing stars:imaging astrometry

Suspect and non-targeted screening of chemical pollutants in Botswana's aquatic environments

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emerging Contaminants 2024年第3期10卷 363-373页

作者： Kgato P.Selwe Charlotte R.head gothatamang N.Phokedi Jens e.T.Andersen J.Brett Sallach Caroline e.h.Dessent Department of Chemistry University of YorkHeslingtonYorkUnited Kingdom Department of environment and geography University of YorkHeslingtonYorkUnited Kingdom Department of Biology University of YorkHeslingtonYorkUnited Kingdom Department of Chemical and Forensic Sciences Botswana International University of Science and TechnologyBotswana

Chemical pollution in the aquatic systems of Botswana has been sparsely studied despite its potential ecological ***,we perform a study of water samples collected from 13 locations distributed across Botswana to obtain the first overview of the nature and distribution of chemical contaminants across the country's aquatic *** resolution mass spectrometry was applied using nontargeted and suspect screening methods to qualitatively analyse samples.A total of 114 contaminants of emerging concern(CeCs)were identified including 68(59.6%)pharmaceuticals and pharmaceutical metabolites;16(14.2%)pesticides;13(11.4%)psychoactive compounds and metabolites;11(9.7%)industrial chemicals and intermediates and lastly,5(4.4%)personal care ***,3,4-dimethylmethcathinone,and diazolidinyl urea represented the most commonly detected pharmaceutical,psychoactive drug and personal care product,*** pesticide dodemorph and three industrial chemicals(stearamide,pthalic acid and bis(2-ethylhexyl)phthalate)were detected in all samples obtained.90 CeCs were detected in receiving water(from 7 sample locations),75 in wastewater(from 3 sample locations)and 60 in surface water(from 9 sample locations).Of the compounds detected,only 8 had been identified in environmental samples acquired in Botswana *** discuss the variations in the nature and frequency of chemical pollutants detected in this work in a geographical *** results indicate that Botswana's aquatic systems are subject to pollution,despite wastewater treatment and that in order to mitigate potentially harmful effects on both human and aquatic ecosystems,more investigations are required to correctly identify,track and tackle the sources of pollution.

关键词： emerging contaminants Chemical pollution Water analysis Pharmaceuticals LC-hRMS/MS

Unmixing detrital zircon U-Pb ages reveals tectonic and climatic depositional influences on the Carboniferous Ansilta Formation,Calingasta-Uspallata Basin,Western Argentina

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geoscience Frontiers 2024年第4期15卷 61-77页

作者： J.R.Malone J.e.Malone J.L.Isbell D.h.Malone J.P.Craddock K.N.Pauls Department of geological Sciences Jackson School of GeosciencesUniversity of Texas at AustinAustinTX 78712USA Iowa geological Survey University of IowaIowa CityIA 52240USA Department of geosciences University of Wisconsin-MilwaukeeMilwaukeeWI 53211USA Department of geography Geology and the EnvironmentIllinois State UniversityNormalIL 61790-4400USA

The Late Paleozoic Ice Age(LPIA)was a principal control of sedimentation across gondwana from the late Devonian through early *** assess the hypothesis that glacial to interglacial transitions in western Argentina were the primary control influencing sediment routing patterns among the various Carboniferous-Permian basins in western *** Carboniferous Ansilta Formation consists of glaciomarine,nearshore,and fluvial systems deposited during the LPIA along the eastern margin of the Calingasta-Uspallata Basin in *** lower,glacially influenced succession of the Ansilta Formation records at least five glacial advances;the upper succession of consists of progradational shallow marine,deltaic,and fluvial *** combine 1225 new U-Pb zircon ages from six samples of the Carboniferous Ansilta Formation in the Calingasta-Uspallata Basin with 5864 U-Pb ages from 147 pub-lished samples in the detrital Pymix forward mixture model to characterize provenance *** the glacially influenced lower Ansilta Formation,sediment was derived locally from the Protoprecordillera,which was a prominent highland with alpine glaciers flowing west and east into the Calingasta-Uspallata and Paganzo basins,***,there was little or no connection between these two basins during Serpukhovian-Bashkirian *** fluvial/deltaic upper Ansilta had distal sediment sources in the Sierras ***,our results support the collapse of the Protoprecordillera topographic barrier,enabling drainage patterns connecting the Paganzo and Calingasta-Uspallata basins by late Pennsylvanian-early Permian time.

关键词： Late Paleozoic Ice Age Argentina Calingasta-Uspallata Basin Ansilta Formation Detrital zircon provenance

Assessment of the piroxicam-incited model of synchronized colitis in T-cell receptor alpha chain-deficient mice

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Animal Models and experimental Medicine 2024年第4期7卷 533-543页

作者： Maximo e.Lange Danisa M.Bescucci Valerie F.Boras Tony Montina g.Douglas Inglis douglas inglis 11 lethbridge research and development centre agriculture and agri-food canadalethbridgealbertacanada alberta health services chinook regional hospitallethbridgealbertacanada department of chemistry and biochemistry university of lethbridgelethbridgealbertacanada southern alberta genome sciences centre university of lethbridgelethbridgealbertacanada

Background:A multitude of mouse models are utilized to emulate and study intestinal inflammation.T-cell receptor alpha chain(TCRα)-deficient mice are used as a model of spontaneous colitis that has similarities with human ulcerative ***,colitis is triggered late in the life of the mouse(age:4-5 months),and inflammation does not develop at the same time in different mice.A previously conducted study reported that the administration of the drug piroxicam triggered predictable and early colitis in TCRα-deficient mice at the age of 6-8 ***,a detailed characterization of ensuing inflammation was not ***:We conducted an in-depth examination of piroxicam-triggered colitis in TCRα-deficient mice,with emphasis on spatial histopathologic changes and analysis of expression of inflammatory ***,we tested amelioration of colitis with ***:We confirmed that piroxicam induced a time-prescribed colitis and did so in the proximal colon as well as the cecum of TCRα-deficient *** adminis-tration was observed to induce epithelial hyperplasia,goblet cell loss,and leukocyte infiltration with occasional ulceration.A Swiss roll technique was used to examine the colon and cecum in its ***,we observed that inflammation was mul-tifocal segmental,with areas of tissue damage in between healthy *** addition,we observed variability in the severity of inflammation among replicate animals and treatments,and that the administration of dexamethasone only partially ameliorated inflammation in the proximal ***:Piroxicam consistently induced multifocal segmental colitis in the proxi-mal colon and cecum,although the degree of inflammation was reduced in the ***,spatial variability in inflammation in the large intestine and the inter-replicate variation in the severity of inflammation must be taken into consideration when utilizing this murine model of synchronized colitis.

关键词： colon dexamethasone histology induction inflammation knockout

Convexification of hybrid AC-DC Optimal Power Flow with Line-Commutated Converters

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CSee Journal of Power and energy Systems 2024年第2期10卷 617-628页

作者： hongyuan Liang Zhigang Li J.h.Zheng Q.h.Wu School of electric Power engineering South China University of TechnologyGuangzhou 510641China

Line-commutated converter (LCC)-based high-voltage DC (hVDC) systems have been integrated with bulk AC power grids for interregional transmission of renewable power. The nonlinear LCC model brings additional nonconvexity to optimal power flow (OPF) of hybrid AC-DC power grids. A convexification method for the LCC station model could address such nonconvexity but has rarely been discussed. We devise an equivalent reformulation for classical LCC station models that facilitates second-order cone convex relaxation for the OPF of LCC-based AC-DC power grids. We also propose sufficient conditions for exactness of convex relaxation with its proof. equivalence of the proposed LCC station models and properties, exactness, and effectiveness of convex relaxation are verified using four numerical simulations. Simulation results demonstrate a globally optimal solution of the original OPF can be efficiently obtained from relaxed model.

关键词： AC-DC power system convex relaxation linecommutated converter optimal power flow second-order cone programming

CLASSIFICATIONS OF DUPIN hYPeRSURFACeS IN LIe SPheRe geOMeTRY

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Acta Mathematica Scientia 2024年第1期44卷 1-36页

作者： Thomas e.CeCIL Department of Mathematics and Computer Science College of the Holy CrossWorcesterMA01610USA

This is a survey of local and global classification results concerning Dupin hypersurfaces in S^(n)(or R^(n))that have been obtained in the context of Lie sphere *** emphasis is on results that relate Dupin hypersurfaces to isoparametric hypersurfaces in *** with these classification results,many important concepts from Lie sphere geometry,such as curvature spheres,Lie curvatures,and Legendre lifts of submanifolds of S^(n)(or R^(n)),are described in *** paper also contains several important constructions of Dupin hypersurfaces with certain special properties.

关键词： Dupin hypersurfaces isoparametric hypersurfaces Lie sphere geometry Lie sphere transformations Lie curvatures

harmonics in the Squirrel Cage Induction Motor Analytic Calculation Part III: Influence on the Torque-speed Characteristic

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CeS Transactions on electrical Machines and Systems 2024年第1期8卷 86-102页

作者： g.Kovács the ganz electric Works BudapestHungary

The harmonics that appear in the squirrel cage asynchronous machine have been discussed in great detail in the literature for a long time. however, the systematization of the phenomenon is still pending, so we made an attempt to fill this gap in the previous parts of our study by elaborating formulas for calculation of parasitic torques. It was a general demand among those who work in this field towards the author to verify his formulas with measurements. In the literature, it seems,only one detailed, purposeful series of measurements has been published so far, the purpose of which was to investigate the effect of the number of rotor slots on the torque-speed characteristic curve of the machine. The main goal of this study is to verify the correctness of the formulas by comparing them with the referred series of measurements. Relying on this, the expected synchronous parasitic torques were developed for the frequently used rotor slot numbers-as a design guide for the ***, together with our complete table for radial magnetic pull published in our previous work, the designer has all the principles, data and formulas available for the right number of rotor slots for his given machine and for the drive system. This brings this series of papers to an end.

关键词： Asynchronous parasitic torques Induction motor Squirrel cage rotor Space harmonics Synchronous parasitic torques