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Unveiling the atomic-scale transition between light harvesting and photoprotective states in plant photosynthesis

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Science China Chemistry 2024年第5期67卷 1375-1377页

作者： alexander v.Ruban School of Biological and Behavioural Sciences Queen Mary University of LondonLondon E14NSUK

Non-photochemical chlorophyll fluorescence quenching(NPQ) stands as a cornerstone in the realm of photosynthesis research, attracting generations of dedicated scientists in their quest to unravel its mysteries. This mechanism, crucial for safeguarding photosynthesis, plays a pivotal role in regulating light harvesting, particularly in oxygenic photosynthesis where the oxygen-evolving photosystem II (PSII)is susceptible to photodamage [1].

关键词： harvesting protective attracting

Interatomic Interaction Models for Magnetic Materials:Recent Advances

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Chinese Physics Letters 2024年第6期41卷 54-66页

作者： Tatiana S.Kostiuchenko alexander v.Shapeev Ivan S.Novikov Emanuel Institute of Biochemical Physics RAS 4 Kosygin StreetMoscow119334Russian Federation Independent investigator

Atomistic modeling is a widely employed theoretical method of computational materials science.It has found particular utility in the study of magnetic materials.Initially,magnetic empirical interatomic potentials or spinpolarized density functional theory(DFT)served as the primary models for describing interatomic interactions in atomistic simulations of magnetic systems.Furthermore,in recent years,a new class of interatomic potentials known as magnetic machine-learning interatomic potentials(magnetic MLIPs)has emerged.These MLIPs combine the computational efficiency,in terms of CPU time,of empirical potentials with the accuracy of DFT calculations.In this review,our focus lies on providing a comprehensive summary of the interatomic interaction models developed specifically for investigating magnetic materials.We also delve into the various problem classes to which these models can be applied.Finally,we offer insights into the future prospects of interatomic interaction model development for the exploration of magnetic materials.

关键词： materials interaction empirical

Praseodymium metal nanorods as a 5-fluorouracil carrier

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Journal of Rare Earths 2024年第7期42卷 1328-1336页

作者： varnitha Manikantan Govindaraj Sri varalakshmi Ujma Ashapak Tamboli Archana Sumohan Pillai Aleyamma alexander Anushka Lucas Bose Allben Akash Israel v.M.v.Enoch Centre for Nanoscience and Genomics Karunya Institute of Technology and Sciences (Deemed University) Department of Applied Chemistry Karunya Institute of Technology and Sciences (Deemed University)

Interest in metal nanoparticles as nanoscale drug-carrying vehicles has been increasing.In such an aspect,lanthanide metal nanoparticles are particularly intriguing.Herein,we report praseodymium nanoparticles as a novel anticancer therapeutic transporting agent.The material was made as a composite with the supramolecular host polymer,poly-β-cyclodextrin.The praseodymium nanorods were characterized using standard analytical techniques,including X-ray diffraction（XRD）,X-ray photoelectron spectroscopy（XPS）,and thermogravimetric analysis（TGA）.In addition,they were imaged using transmission electron microscopy.The nanostructures are a long rod-shaped material with 2.0±0.1 μm in length and 230±10 nm in width.The material shows a saturation magnetization value above 30 emu/g with a coercivity value of 130 Oe.The nanocarrier is freighted with the drug 5-fluorouracil,and the encapsulation efficiency is 76.09%.The drug release is continuous from the nanocarrier（polymer-containing praseodymium nanoparticles） and proceeds for above 250 h.The in vitro cytotoxicities of the blank nanocarrier and the 5-fluorouracil-loaded one are deduced by testing them on MCF-7 and vero（non-cancerous） cell lines.The cytotoxicity on the cancerous cell lines is observed,whereas the noncancerous cells are unaffected.The IC50values on the cell lines are reported.

关键词： Anticancer activity Drug delivery Metal nanoparticles Poly-cyclodextrin Praseodymium Rare earths

Cluster Analysis of the Roma-BZCAT Blazars

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Research in Astronomy and Astrophysics 2024年第5期24卷 117-139页

作者： Dmitry O.Kudryavtsev Yulia v.Sotnikova vladislav A.Stolyarov Timur v.Mufakharov valery v.vlasyuk Margarita L.Khabibullina alexander G.Mikhailov Yulia v.Cherepkova Special Astrophysical Observatory of the Russian Academy of Sciences Nizhny Arkhyz 369167Russia Astrophysics Group Cavendish LaboratoryUniversity of CambridgeCambridge CB3 OHEUK Kazan Federal University 18 Kremlyovskaya StKazan 420008Russia

Based on the collected multiwavelength data, namely in the radio(NvSS, FIRST, RATAN-600), IR(WISE),optical(Pan-STARRS), Uv(GALEX), and X-ray(ROSAT, Swift-XRT) ranges, we have performed a cluster analysis for the blazars of the Roma-BZCAT catalog. Using two machine learning methods, namely a combination of PCA with k-means clustering and Kohonen's self-organizing maps(SOMs), we have constructed an independent classification of the blazars(five classes) and compared the classes with the known Roma-BZCAT classification(FSRQs, BL Lacs, galaxy-dominated BL Lacs, and blazars of an uncertain type) as well as with the high synchrotron peaked(HSP) blazars from the 3HSP catalog and blazars from the TevCat catalog. The obtained groups demonstrate concordance with the BL Lac/FSRQ classification along with a continuous character of the change in the properties. The group of HSP blazars stands out against the overall distribution. We examine the characteristics of the five groups and demonstrate distinctions in their spectral energy distribution shapes. The effectiveness of the clustering technique for objective analysis of multiparametric arrays of experimental data is demonstrated.

关键词： methods data analysis-galaxies active-(galaxies:)BL Lacertae objects general

Elucidating elusive quaternary selenide EuCeCuSe3:Synthesis,crystal structure,properties and theoretical studies

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Journal of Rare Earths 2024年第1期42卷 163-171,I0006页

作者： Maxim v.Grigoriev Anna v.Ruseikina Maxim S.Molokeev vladimir A.Chernyshev Aleksandr S.Aleksandrovsky alexander S.Krylov Svetlana N.Krylova Nikolai P.Shestakov Dmitriy A.velikanov alexander A.Garmonov Alexey v.Matigorov Evgeny A.Ostapchuk Thomas Schleid Damir A.Safin Laboratory of Theory and Optimization of Chemical and Technological Processes University of TyumenVolodarskogo Str.6625003TyumenRussian Federation Kirensky Institute of Physics Federal Research Center KSC SB RASAkademgorodok 50 Bld.38660036KrasnoyarskRussian Federation Department of Physics Far Eastern State Transport UniversitySerysheva Str.47680021KrasnoyarskRussian Federation Institute of Natural Sciences and Mathematics Ural Federal University Named After the First President of Russia B.N.YeltsinMira Str.19620002EkaterinburgRussian Federation Department of Photonics and Laser Technology Siberian Federal UniversitySvobodnii Ave.79660079KrasnoyarskRussian Federation Institute of Physics and Technology University of TyumenVolodarskogo Str.6625003 TyumenRussian Federation Institute for Inorganic Chemistry University of StuttgartPfaffenwaldring 55D-70569StuttgartGermany Scientific and Educational and Innovation Center for Chemical and Pharmaceutical Technologies Ural Federal University named after the First President of Russia B.N.YeltsinMira Str.19620002 EkaterinburgRussian Federation University of Tyumen Volodarskogo Str.6625003TyumenRussian Federation

We report on the novel heterometallic quaternary selenide EuCeCuSe3,the fabrication of which has been a challenge until this work.The structure of the reported selenide was elucidated from the powder X-ray diffraction data,which revealed the formation of EuCeCuSe3with excellent yield(96.7%)accompanied with a minor fraction of CeSe2(3.3%),and was best solved in orthorhombic space group Pnma with the BaLaCuS3structural type.Thus,the crystal structure of the title compound completes the row of the heterometallic quaternary selenides EuRECuSe3(RE=La,Pr,Nd,Sm,Eu,Gd,Tb,Dy,Ho,Er,Tm,Yb,Lu,Y),of which the cerium-based derivative exclusively belongs to the BaLaCuS3structural type.The distortion of the CuSe4polyhedron was compared for the whole series of EuRECuSe3compounds using theτ4-descriptor for four coordinated ions,which revealed the highest degree of distortion for the Ce3+-containing selenide,followed by the La3+-based derivative.Furthermore,the crystallographic and geometrical parameters of the reported selenide were discussed in comparison to the Ce3+-based sulfides SrCeCuS3and EuCeCuS3.Ab initio calculations of the crystal structure,a phonon spectrum and elastic constants for the crystal of EuCeCuSe3were also performed.The types and wavenumbers of fundame ntal modes were determined and the involvement of ions participating in the phonon modes was assessed.The experimental IR spectrum of the reported selenide was interpreted and found to be in agreement with the calculated spectrum.The experimental direct band gap of EuCeCuSe3was measured to be 1.36 ev that is consistent with the concept of its origin due to interband transitions between orbitals emerging mainly from 4f(valence band)and 5d(conduction band)levels of the Eu2+cation.The dependence of the Young’s modulus on the direction demonstrates the anisotropy of the elastic properties,while the vickers hardness for EuCeCuSe3was calculated to be 5.2 GPa.Finally,the title compound is paramagnetic above 4 K.

关键词： Quaternary selenide Synthesis Crystal structure Ab initio calculations Magnetic measurements Spectroscopy

Peculiarities of Ethylene Polymerization Reactions with Bis(imino)pyridyl Complexes of CoCl_(2) and FeCl_(2)

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Chinese Journal of Polymer Science 2024年第4期42卷 492-500页

作者： Laura A.Rishina Yury v.Kissin Svetlana S.Lalayan Artem A.Antonov vadim G.Krasheninnikov alexander A.Gulin N.N.Semenov Federal Research Center for Chemical Physics Russian Academy of Sciences4 Kosygin St.Moscow119991Russia Department of Chemistry and Chemical Biology RutgersThe State University of New Jersey123 Bevier Rd.PiscatawayNJ08854USA Boreskov Institute of Catalysis Russian Academy of Sciences5 Lavrentieva Prosp.Novosibirsk630090Russia

The article describes ethylene polymerization reactions with transition metal catalysts based on complexes of CoCl_(2) and FeCl_(2) with an N,N,N-tridentate ligand 2,6-bis[1-(2,6-dimethylphenylimino)ethyl]pyridine. The complexes are converted into polymerization catalysts by reacting them either with polymethylalumoxane (MAO) or with a combination of Al(C2H5)2Cl and Mg(C4H9)2 at an [Al]:[Mg] ratio of ~3. Both MAO-activated complexes readily polymerize ethylene at 35 ℃ with the formation of linear, low molecular weight polymers with a narrow molecular weight distribution. The same complexes, when activated with the Al(C2H5)2Cl-Mg(C4H9)2 combination, form multi-center catalysts and generate polyethylenes with a broad molecular weight distribution.

关键词： Ethylene polymerization Bis(imino)pyridyl complexes of CoCl_(2)and FeCl_(2) Molecular-weight distribution Polymer chain structure

Exploring van der Waals materials with high anisotropy:geometrical and optical approaches

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Light(Science & Applications) 2024年第4期13卷 645-653页

作者： Aleksandr S.Slavich Georgy A.Ermolaev Mikhail K.Tatmyshevskiy Adilet N.Toksumakov Olga G.Matveeva Dmitriy v.Grudinin Kirill v.voronin Arslan Mazitov Konstantin v.Kravtsov alexander v.Syuy Dmitry M.Tsymbarenko Mikhail S.Mironov Sergey M.Novikov Ivan Kruglov Davit A.Ghazaryan Andrey A.vyshnevyy Aleksey v.Arsenin valentyn S.volkov Kostya S.Novoselov Moscow Center for Advanced Studies Kulakova str.20Moscow 123592Russia. Emerging Technologies Research Center XPANCEOInternet CityEmmay TowerDubaiUnited Arab Emirates. Donostia International Physics Center(DIPC) Donostia/San-Sebastián 20018Spain. Institute of Materials Ecole Polytechnique Federale de Lausanne1015 LausanneSwitzerland. Department of Chemistry Lomonosov Moscow State UniversityMoscow 119991Russia. Laboratory of Advanced Functional Materials Yerevan State UniversityYerevan 0025Armenia. National Graphene Institute(NGI) University of ManchesterManchester M139PLUK. Department of Materials Science and Engineering National University of SingaporeSingapore 03-09 EASingapore. Institute for Functional Intelligent Materials National University of Singapore117544 SingaporeSingapore

The emergence of van der Waals(vdW)materials resulted in the discovery of their high optical,mechanical,and electronic anisotropic properties,immediately enabling countless novel phenomena and applications.Such success inspired an intensive search for the highest possible anisotropic properties among vdW materials.Furthermore,the identification of the most promising among the huge family of vdW materials is a challenging quest requiring innovative approaches.Here,we suggest an easy-to-use method for such a survey based on the crystallographic geometrical perspective of vdW materials followed by their optical characterization.Using our approach,we found As2S3 as a highly anisotropic vdW material.It demonstrates high in-plane optical anisotropy that is~20%larger than for rutile and over two times as large as calcite,high refractive index,and transparency in the visible range,overcoming the century-long record set by rutile.Given these benefits,As2S3 opens a pathway towards nextgeneration nanophotonics as demonstrated by an ultrathin true zero-order quarter-wave plate that combines classical and the Fabry–Pérot optical phase accumulations.Hence,our approach provides an effective and easy-to-use method to find vdW materials with the utmost anisotropic properties.

关键词： anisotropy anisotropic high

A new perspective on intervertebral disc calcification—from bench to bedside

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Bone Research 2024年第1期12卷 50-61页

作者： Emanuel J.Novais Rajkishen Narayanan Jose A.Canseco Koen van de Wetering Christopher K.Kepler Alan S.Hilibrand alexander R.vaccaro Makarand v.Risbud Department of Orthopaedic Surgery Sidney Kimmel Medical CollegeThomas Jefferson UniversityPhiladelphiaPAUSA Unidade Local de Saúde do Litoral Alentejano Orthopedic DepartmentSantiago do CacémPortugal Rothman Orthopedic Institute at Thomas Jefferson University PhiladelphiaPAUSA

Disc degeneration primarily contributes to chronic low back and neck pain.Consequently,there is an urgent need to understand the spectrum of disc degeneration phenotypes such as fibrosis,ectopic calcification,herniation,or mixed phenotypes.Amongst these phenotypes,disc calcification is the least studied.Ectopic calcification,by definition,is the pathological mineralization of soft tissues,widely studied in the context of conditions that afflict vasculature,skin,and cartilage.Clinically,disc calcification is associated with poor surgical outcomes and back pain refractory to conservative treatment.It is frequently seen as a consequence of disc aging and progressive degeneration but exhibits unique molecular and morphological characteristics:hypertrophic chondrocyte-like cell differentiation;TNAP,ENPP1,and ANK upregulation;cell death;altered Pi and PPi homeostasis;and local inflammation.Recent studies in mouse models have provided a better understanding of the mechanisms underlying this phenotype.It is essential to recognize that the presentation and nature of mineralization differ between AF,NP,and EP compartments.Moreover,the combination of anatomic location,genetics,and environmental stressors,such as aging or trauma,govern the predisposition to calcification.Lastly,the systemic regulation of calcium and Pi metabolism is less important than the local activity of PPi modulated by the ANK-ENPP1 axis,along with disc cell death and differentiation status.While there is limited understanding of this phenotype,understanding the molecular pathways governing local intervertebral disc calcification may lead to developing disease-modifying drugs and better clinical management of degeneration-related pathologies.

关键词： degeneration metabolism intervertebral

Increasingβ-hexosaminidase A activity using genetically modified mesenchymal stem cells

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Neural Regeneration Research 2024年第1期19卷 212-219页

作者： Alisa A.Shaimardanova Daria S.Chulpanova valeriya v.Solovуeva Shaza S.Issa Aysilu I.Mullagulova Angelina A.Titova Yana O.Mukhamedshina Anna v.Timofeeva alexander M.Aimaletdinov Islam R.Nigmetzyanov Albert A.Rizvanov Institute of Fundamental Medicine and Biology Kazan Federal UniversityKazanRussia Department of Histology Cytology and EmbryologyKazan State Medical UniversityKazanRussia

GM2 gangliosidoses are a group of autosomal-recessive lysosomal storage disorde rs.These diseases result from a deficiency of lysosomal enzymeβ-hexosaminidase A(HexA),which is responsible for GM2 ganglioside degradation.HexA deficiency causes the accumulation of GM2-gangliosides mainly in the nervous system cells,leading to severe progressive neurodegeneration and neuroinflammation.To date,there is no treatment for these diseases.Cell-mediated gene therapy is considered a promising treatment for GM2 gangliosidoses.This study aimed to evaluate the ability of genetically modified mesenchymal stem cells(MSCs-HEXA-HEXB)to restore HexA deficiency in Tay-Sachs disease patient cells,as well as to analyze the functionality and biodistribution of MSCs in vivo.The effectiveness of HexA deficiency cross-correction was shown in mutant MSCs upon intera ction with MSCs-HEXA-HEXB.The results also showed that the MSCs-HEXA-HEXB express the functionally active HexA enzyme,detectable in vivo,and intravenous injection of the cells does not cause an immune response in animals.These data suggest that genetically modified mesenchymal stem cells have the potentials to treat GM2 gangliosidoses.

关键词： adeno-associated viral vectors cell therapy cell-mediated gene therapy gene therapy GM2 gangliosidosis Sandhoff disease Tay-Sachs disease β-hexosaminidase