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Integrative Zoology 2008年第4期3卷 322-332页

作者： Igor G.KHOROZYAN alexander G.MALKHASYAN Alexei v.ABRAMOv Zoological Institute Russian Academy of SciencesSt PetersburgRussia Ministry of Nature Protection of the Republic of Armenia YerevanArmenia

It is important to predict how many individuals of a predator species can survive in a given area on the basis of prey sufficiency and to compare predictive estimates with actual numbers to understand whether or not key threats are related to prey *** terrain and low detection probabilities do not allow for the use of traditional prey count techniques in mountain *** used presence–absence occupancy modeling and camera-trapping to estimate the abundance and densities of prey species and regression analysis to predict leopard(Panthera pardus)densities from estimated prey biomass in the mountains of the Nuvadi area,Meghri Ridge,southern *** prey densities were 12.94±2.18 individuals km–2 for the bezoar goat(Capra aegagrus),6.88±1.56 for the wild boar(Sus scrofa)and 0.44±0.20 for the roe deer(Capreolus capreolus).The detection probability of the prey was a strong function of the activity patterns,and was highest in diurnal bezoar goats(0.59±0.09).Based on robust regression,the estimated total ungulate prey biomass(720.37±142.72 kg km–2)can support a leopard density of 7.18±3.06 individuals 100 km–*** actual leopard density is only 0.34 individuals 100 km–2(*** subadult male recorded over the 296.9 km2),estimated from tracking and *** most plausible explanation for this discrepancy between predicted and actual leopard density is that poaching and disturbance caused by livestock breeding,plant gathering,deforestation and human-induced wild fires are affecting the leopard population in Armenia.

关键词： Armenia leopard linear regression presence–absence prey.

Disease modifying treatment of spinal cord injury with directly reprogrammed neural precursor cells in non-human primates

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World Journal of Stem Cells 2021年第5期13卷 452-469页

作者： vladimir P Baklaushev Oleg v Durov vladimir A Kalsin Eugene v Gulaev Sergey v Kim Ilya L Gubskiy veronika A Revkova Ekaterina M Samoilova Pavel A Melnikov Dzhina D Karal-Ogly Sergey v Orlov alexander v Troitskiy vladimir P Chekhonin alexander v Averyanov Jan-Eric Ahlfors Biomedical Research Federal Research and Clinical Center of Specialized Medical Care and Medical TechnologiesFMBA of RussiaMoscow 115682MoskvaRussia Department of Neurosurgery Federal Research and Clinical Center of Specialized Medical Care and Medical TechnologiesFMBAMoscow 115682MoskvaRussia Department of Anesthesiology N.N.Blokhin Russian Cancer Research CentreMoscow 115478MoskvaRussia Radiology and Clinical Physiology Scientific Research Center Federal center of brain research and neurotechnologies of the Federal Medical Biological AgencyMoscow 117997Russia Department of Neurobiology Serbsky National Medical Research Center for Psychiatry and NarcologyMoscow 119992MoskvaRussia Department of Primatology Russian Acad Med SciResearch Institute of Medical PrimatologySochi 119992SochiRussia Department of vascular Surgery Federal Research and Clinical Center of Specialized Medical Care and Medical TechnologiesFMBA of RussiaMoscow 115682MoskvaRussia Department of Basic and Applied Neurobiology V.P.Serbsky Federal Medical Research Center for Psychiatry and NarcologyRussia Department of Medical Nanobiotechnology Pirogov Russian National Research Medical University(RNRMU)Moscow 115682MoskvaRussia New World Laboratories Laval H7V 4A7QuebecCanada

BACKGROUND The development of regenerative therapy for human spinal cord injury(SCI)is dramatically restricted by two main challenges:the need for a safe source of functionally active and reproducible neural stem cells and the need of adequate animal models for preclinical *** reprogramming of somatic cells into neuronal and glial precursors might be a promising solution to the first *** use of non-human primates for preclinical studies exploring new treatment paradigms in SCI results in data with more translational relevance to human *** To investigate the safety and efficacy of intraspinal transplantation of directly reprogrammed neural precursor cells(drNPCs).METHODS Seven non-human primates with verified complete thoracic SCI were divided into two groups:drNPC group(n=4)was subjected to intraspinal transplantation of 5 million drNPCs rostral and caudal to the lesion site 2 wk post injury,and lesion control(n=3)was injected identically with the equivalent volume of *** Follow-up for 12 wk revealed that animals in the drNPC group demonstrated a significant recovery of the paralyzed hindlimb as well as recovery of somatosensory evoked potential and motor evoked potential of injured *** resonance diffusion tensor imaging data confirmed the intraspinal transplantation of drNPCs did not adversely affect the morphology of the central nervous system or cerebrospinal fluid *** immunohistochemical analysis showed that drNPCs maintained SOX2 expression characteristic of multipotency in the transplanted spinal cord for at least 12 wk,migrating to areas of axon growth *** Our data demonstrated that drNPC transplantation was safe and contributed to improvement of spinal cord function after acute SCI,based on neurological status assessment and neurophysiological recovery within 12 wk after *** functional improvement described was not associated with neuronal differentiation of th

关键词： Direct cell reprogramming Neural precursor cells Directly reprogrammed neural precursor cells Spinal cord injury Nonhuman primates Regenerative therapy,Evoked potentials

Chemotactic signaling in mesenchymal cells compared to amoeboid cells

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Genes & Diseases 2014年第2期1卷 162-173页

作者： alexander v.vorotnikov Pyotr A.Tyurin-Kuzmin Faculty of Fundamental Medicine M.V.Lomonosov Moscow State UniversityMoscowRussian Federation Institute of Experimental Cardiology Russian Cardiology Research and Production ComplexMoscowRussian Federation

Cell chemotaxis plays a pivotal role in normal development,inflammatory response,injury repair and tissue regeneration in all *** is also a critical contributor to cancer metastasis,altered angiogenesis and neurite growth in *** molecular mechanisms regulating chemotaxis are currently being identified and key components may be pertinent therapeutic *** these components appear to be mostly common in various cells,there are important differences in chemotactic signaling networks and signal processing that result in the distinct chemotactic behavior of mesenchymal cells compared to much better studied amoeboid blood *** differences are not necessarily predetermined based on cell type,but are rather chosen and exploited by cells to modify their chemotactic behavior based on physical constraints and/or environmental *** results in a specific type of chemotactic migration in mesenchymal cells that can be selectively targeted in ***,we compare the chemotactic behavior,signaling and motility of mesenchymal and amoeboid *** suggest that the current model of chemotaxis is applicable for small amoeboid cells but needs to be reconsidered for large mesenchymal *** focus on new candidate regulatory molecules and feedback mechanisms that may account for mesenchymal cell type-specific chemotaxis.

关键词： Chemotaxis Feedback regulation Fibroblasts Hydrogen peroxide Signaling

NIR emitting terephthalates(SmxDyyGd1-x-y)2(tph)3(H2O)4 for luminescence thermometry in the physiological range

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Journal of Rare Earths 2020年第5期38卷 492-497页

作者： Anastasia v.Orlova vladislava Yu.Kozhevnikova Leonid S.Lepnev alexander S.Goloveshkin Irina M.Le-Deigen valentina v.Utochnikova M.v.Lomonosov Moscow State University 1/3 Leninskye GoryMoscow119991Russian Federation P.N.Lebedev Physical Institute Leninsky prosp.531J9991MoscowRussian Federation A.N.Nesmeyanov Institute of Organoelement Compounds Russian Academy of SciencesVavilova St.28119991MoscowRussian Federation EvOLED Ltd. 1A-24 Puskina ielaRiga LV-1050Latvia

The first luminescence thermometer based on coordination compound of samarium and dysprosium is repo *** luminescence intensity and high signal resolution are reached thanks to the concentration quenching reduction due to the use of the trimetallic complexes of *** best thermometric properties in a wide temperature range among the studied systems are demonstrated by(Sm0.2Dy0.15Gd0.65)2(tph)3(H2O)*** sensitivity reaches 0.5%/K in visible range and 1.2%/K in NIR range at low temperatures and 0.5%/K and 0.8%/K in physiological range.

关键词： Luminescence Lanthanides Carboxylates Thermometry NIR range Rare earths

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,I0005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)Coimbatore641114Tamil NaduIndia Department of Applied Chemistry Karunya Institute of Technology and Sciences(Deemed University)Coimbatore641114Tamil NaduIndia

Interest in metal nanoparticles as nanoscale drug-carrying vehicles has been *** such an aspect,lanthanide metal nanoparticles are particularly ***,we report praseodymium nanoparticles as a novel anticancer therapeutic transporting *** material was made as a composite with the supramolecular host polymer,poly-β-*** 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 *** nanostructures are a long rod-shaped material with 2.0±0.1μm in length and 230±10 nm in *** material shows a saturation magnetization value above 30 emu/g with a coercivity value of 130 *** 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 *** 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 *** cytotoxicity on the cancerous cell lines is observed,whereas the non-cancerous cells are *** IC_(50)values on the cell lines are reported.

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

Effect of electron injection in copper-contacted graphene nanoribbons

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Nano Research 2016年第9期9卷 2735-2746页

作者： Konstantin A.Simonov Nikolay A.vinogradov alexander S.vinogradov alexander v.Generalov Gleb I.Svirskiy Attilio A.Cafolla Nils Martensson Alexei B. Preobrajenski Department of Physics and Astronomy Uppsala UniversityUppsala Box 51675120Sweden MAX Ⅳ Laboratory Lund UniversityLund Box 11822100Sweden v.A.Fock Institute of Physics St.Petersburg State UniversitySt.Petersburg 198504Russia School of Physical Sciences Dublin City UniversityDublin 9Ireland

For practical electronic device applications of graphene nanoribbons (GNRs), it is essential to have abrupt and well-defined contacts between the ribbon and the adjacent metal lead. By analogy with graphene, these contacts can induce electron or hole doping, which may significantly affect the I/v characteristics of the device. Cu is among the most popular metals of choice for contact materials. In this study, we investigate the effect of in situ intercalation of Cu on the electronic structure of atomically precise, spatially aligned armchair GNRs of width N = 7 (7-AGNRs) fabricated via a bottom-up method on the Au(788) surface. Scanning tunneling microscopy data reveal that the complete intercalation of about one monolayer of Cu under 7-AGNRs can be facilitated by gentle annealing of the sample at 80 °C. Angle-resolved photoemission spectroscopy (ARPES) data clearly reflect the one-dimensional character of the 7-AGNR band dispersion before and after intercalation. Moreover, ARPES and core-level photoemission results show that intercalation of Cu leads to significant electron injection into the nanoribbons, which causes a pronounced downshift of the valence and conduction bands of the GNR with respect to the Fermi energy (ΔE ~ 0.5 ev). As demonstrated by ARPES and X-ray absorption spectroscopy measurements, the effect of Cu intercalation is restricted to n-doping only, without considerable modification of the band structure of the GNRs. Post-annealing of the 7-AGNRs/Cu/Au(788) system at 200 °C activates the diffusion of Cu into Au and the formation of a Cu-rich surface Au layer. Alloying of intercalated Cu leads to the recovery of the initial position of GNR-related bands with respect to the Fermi energy (E F), thus, proving the tunability of the induced n-doping.

关键词： graphene nanoribbons bottom-up method copper intercalation charge injection angle-resolved photoemission spectroscopy (ARPES) scanning tunneling microscopy

Multiscale wood micromechanics and size effects study via nanoindentation

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Journal of Bioresources and Bioproducts 2023年第3期8卷 246-264页

作者： Yuri I.Golovin alexander A.Gusev Dmitry Yu.Golovin Sergey M.Matveev alexander I.Tyrin alexander A.Samodurov viktor v.Korenkov Inna A.vasyukova Maria A.Yunack Institute“Nanotechnology and Nanomaterials” G.R.Derzhavin Tambov State University392000 TambovRussia Department of Chemical Enzymology School of ChemistryLomonosov Moscow State University119991 MoscowRussia Research and Educational Center«Sustainable Development of the Forest Complex» Voronezh State Forestry University Named after G.F.Morozov394087 VoronezhRussia Department of Functional Nanosystems and High-Temperature Materials National University of Science and Technology“MISIS”119991 MoscowRussia

Wood as a material is a natural composite with a complex hierarchically arranged *** scale levels of wood structure contribute to its macroscopic mechanical *** nature of such characteristics and deformation modes differs radically at different scale *** macroscopic properties are well studied,and the relevant information can be easily found in the ***,the knowledge of the deformation mechanisms at the mesoscopic level corresponding to the cellular structure of early and late wood layers of annual growth rings is *** hinders building the comprehensive multiscale model of how wood mechanical properties are *** paper described the results of scanning of mechanical properties of softwood and hardwood samples,such as common pine,small-leaf lime,and pedunculate oak,by means of nanoindentation(NI).The NI technique allows varying the size of deformed region within a wide range by altering maximal load(P max)applied to the indenter so that one can re-peatedly and non-destructively test wood structural components at different scale levels on the same sample without changing the technique or *** was discovered that the effective microhardness(H eff)and Young’s modulus(E eff)decreased manifold with P max growing from 0.2 to 2000 *** drop in H effwas observed when the locally deformed region grew,and re-sulting from P max increase generally follows the rule similar to the Hall-Petch relation for yield stress,strength,and hardness initially established for metals and alloys,though obviously in those cases the underlying internal mechanisms are quite *** nature and micromechanisms of such size effect(SE)in wood revealed using NI were discussed in this *** P maxvich indenter was much smaller than the cell wall ***,in this case,NI measured the internal mechanical properties of the cell wall material as long as free boundaries impact

关键词： Nano/microhardness Scanning nanoindentation Annual growth ring Early and late wood Dendrochronology

Role of the endothelium in inflammatory bowel diseases

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World Journal of Gastroenterology 2011年第5期17卷 578-593页

作者： Walter E Cromer J Michael Mathis Daniel N Granger Ganta v Chaitanya J Steven alexander Department of Cellular Biology and Anatomy LSU Health Sciences Center-Shreveport1501 Kings HighwayShreveportLA 71130-3932United States Department of Cellular and Molecular Physiology LSU Health Sciences Center-Shreveport1501 Kings HighwayShreveportLA 71130-3932United States

Inflammatory bowel diseases(IBD) are a complex group of diseases involving alterations in mucosal immunity and gastrointestinal physiology during both initiation and progressive phases of the *** the core of these alterations are endothelial cells,whose continual adjustments in structure and function coordinate vascular supply,immune cell emigration,and regulation of the tissue *** of the endothelium in IBD(angiogenesis),mediated by inflammatory growth factors,cytokines and chemokines,is a hallmark of active gut disease and is closely related to disease *** endothelium in newly formed or inflamed vessels differs from that in normal vessels in the production of and response to inflammatory cytokines,growth factors,and adhesion molecules,altering coagulant capacity,barrier function and blood cell recruitment in *** review examines the roles of the endothelium in the initiation and propagation of IBD pathology and distinctive features of the intestinal endothelium contributing to these conditions.

关键词： Microvasculature Endothelium Inflamma-tion Nitric oxide Adhesion molecules Crohn's disease Ulcerative colitis Cytokines Chemokines Growth factors

Origin of the neuro-sensory system: new and expected insights from sponges

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Integrative Zoology 2009年第3期4卷 294-308页

作者： EMMANUELLE RENARD Jean vACELET Eve GAZAvE Pascal LAPéBIE Carole BORCHIELLINI alexander v.ERESKOvSKY Centre d’océanologie de Marseille CNRS–Aix-Marseille UniversitéMarseilleFrance Department of Embryology Saint-Petersburg State UniversitySt.PetersburgRussia

The capacity of all cells to respond to stimuli implies the conduction of information at least over short *** multicellular organisms,more complex systems of integration and coordination of activities are *** most animals,the processing of information is performed by a nervous *** the most basal taxa,sponges are nerveless so that it is traditionally assumed that the integrated neuro-sensory system originated only once in Eumetazoa,a hypothesis not in agreement with some recent phylogenomic *** aim of this review is to show that recent data on sponges might provide clues for understanding the origin of this complex ***,sponges are able to react to external stimuli,and some of them display spontaneous movement *** coordinated behaviors involve nervous system-like mechanisms,such as action potentials and/or ***,genomic analyses show that sponges possess genes orthologous to those involved in the patterning or function-ing of the neuro-sensory system in ***,some of these genes are expressed in specific cells(flask cells,choanocytes).Together with ultrastructural data,this gives rise to challenging hypotheses concerning cell types that might play neuro-sensory-like roles in sponges.

关键词： animal evolution choanocyte flask cells nervous system Porifera signal transduction.

Ruthenium-mediated assembly and enhanced stability of heterometallic polystannides[Ru_(2)Sn_(19)]^(4−)and[Ru_(2)Sn_(20)]^(6−)

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Nano Research 2022年第6期15卷 5705-5711页

作者： Wei-Xing Chen Nikolay v.Tkachenko Alvaro Muñoz-Castro alexander I.Boldyrev Zhong-Ming Sun State Key Laboratory of Elemento-Organic Chemistry Tianjin Key Lab of Rare Earth Materials and ApplicationsSchool of Materials Science and EngineeringNankai UniversityTianjin 300350China Department of Chemistry and Biochemistry Utah State University0300 Old Main HillLoganUT 84322-0300USA Grupo de Química Inorgánicay Materiales Moleculares Facultad de IngenieriaUniversidad Autonoma de ChileEl Llano SubercaseauxSantiago 2801Chile

In this work,we report the synthesis and characterization of two novel Ru-containing Zintl clusters:[Sn_(19){Ru(COD)(en)}_(2)]^(4−)and[Sn_(20){Ru(COD)}_(2)]^(6−).The synthesized compounds not only expand the family of Ru-Sn cluster systems but also shed light on the structure of heterometallic complexes in a previously unknown range of tin *** single-crystal X-ray diffraction(XRD)analysis reveals the dimeric nature of the *** different assembly patterns of the formal[Sn(η^(3)-Sn_(9))]monomer were observed:the dimerization through the vertex fusion process and the direct dimerization through the formation of 2c–2e Sn–Snσ*** both clusters,the density functional theory calculations reveal the locallyσ-aromatic nature of the[Sn(η^(3)-Sn_(9))]monomer resulting in two independent magnetic shielding *** believe that our findings will help the community to further explore the fascinating chemistry of polystannide clusters.

关键词： heterometallic clusters aromaticity polystannide ruthenium Zintl anion