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Impact of doping profiles on the formation of laser-active centers in bismuth-doped GeO_(2)–SiO_(2)glass fibers

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Photonics Research 2024年第2期12卷 260-270页

作者： SeRGeY ALYSHeV ALeXANDeR VAKHRUSHeV aleksandr KHeGAI eLeNA FIRSTOVA KONSTANTIN RIUMKIN MIKHAIL MeLKUMOV LYUDMILA ISKHAKOVA ANDReY UMNIKOV SeRGeI FIRSTOV Prokhorov General Physics Institute of the Russian Academy of Sciences Dianov Fiber Optics Research Center119333 MoscowRussia Devyatykh Institute of Chemistry of High-Purity Substances of the Russian Academy of Sciences 603951 Nizhny NovgorodRussia

Multi-wavelength-band transmission technology based on the exploitation of the extended spectral region is considered as a potential approach to increase the transmission capacity in the deployed fiber-optic communication infrastructure.The development of optical amplifiers operating in the O-,e-,S-,and U-telecom bands is an extremely important challenge for the successful implementation of this technology.Bismuth-doped fibers are of increasing interest as gain materials,which can be used to provide broadband amplification in the mentioned telecom bands.This is due to the ability of Bi ions incorporated into glass network to form bismuth active centers(BACs)with specific optical properties,which are primarily determined by the glass modifiers.In this work,the impact of the doping profiles of both Ge atoms as glass modifiers and Bi ions on the BACs formation is studied using a series of bismuth-doped fibers fabricated by the modified chemical vapor deposition(MCVD)technique.The Bi-to-BACs conversion efficiency in various spatial regions of the studied samples is presented.It is turned out that for high-Bi concentration regions,the conversion efficiency is very low(less than 10%).In addition,the relationship of the conversion efficiency to the distribution of Bi ions and/or Ge atoms is discussed.Finally,a continuous-wave laser at 1.46μm with a record slope efficiency of 80%is demonstrated using a Bi-doped fiber with confined doping profile,where the Bi-to-BACs conversion efficiency is 35%.This paper provides new information which might help to facilitate understanding of the features of Bi-doped fibers and their potentially achievable characteristics.

关键词： fiber fibers bismuth

Septic arthritis of the hand:Current issues of etiology,pathogenesis,diagnosis,treatment

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World Journal of Orthopedics 2022年第7期13卷 622-630页

作者： Konstantin V Lipatov Arthur Asatryan George Melkonyan aleksandr D Kazantcev ekaterina I Solov'eva Urii e Cherkasov Department of General Surgery Institute of Clinical Medicine named after N.V.SklifosovskySechenov First Moscow State Medical University(Sechenov University)Moscow 119021Russia Wound and Wound Infection Surgery State Budgetary Institution“City Clinical Hospital named after S.S.Yudin of Moscow Healthcare Department”Moscow 115446Russia Department of General Surgery Physician of The Hospital for War Veterans No 3Moscow 129336Russia Department of General Surgery I.M.Sechenov First Moscow State Medical UniversityMoscow 119048Russia

Septic arthritis of the hand is a serious disease that often results in dysfunction of the joint or even the need to perform amputation of the finger.They rank second in the frequency of occurrence after lesions of the knee joint.Many points concerning the etiology,the timing of the development of cartilage destruction and the development of osteomyelitis,approaches to surgical treatment,the duration of antibiotic therapy,and the start of rehabilitation measures remain the subject of numerous discussions.Based on a search in the PubMed,Web of Science and Google Scholar databases down to 1990-2021,publications on septic arthritis of the hand were found and analyzed.The following inclusion criteria were used in our review:(1) Septic arthritis of the hand;(2) Published in a peer review journal;(3) Written in english;and(4) Full text version available.Studies were excluded if they met any of the following criteria:(1) Letters;(2) Articles published in abstract form only;and(3) Cadaveric studies.Septic arthritis of the hand was characterized by the most frequent damage to the joints of the index and middle fingers(> 50% of cases).Up to 90% of cases,the infection enters the joint as a result of penetrating trauma,animal bites,etc.Staphylococcus aureus became the most frequently isolated microorganism(30%-55%),and its polyantibiotic-resistant form Methicillin-resistant Staphylococcus aureus was found,according to various sources,from 0% to 73% among all isolated Staphylococcus aureus.In arthritis,Pasteurella multocida(6%-11%) is often isolated as a result of animal bites.Articular cartilage destruction in the experiment developed within 24-48 h after infection.In clinical studies,the development of osteomyelitis was noted when treatment was delayed by more than 10 d.X-ray data during the first two weeks were uninformative.Priority of surgical treatment of septic arthritis.Drainage and surgical treatment,and with the development of osteomyelitis,the implementation of arthrodesis.Antibacterial therapy for 2-4 wk and early

关键词： Septic arthritis Hand Staphylococcus aureus Metacarpophalangeal joint Interphalangeal joint Rehabilitation

energy efficiencies and CO_(2)emissions associated with lowtemperature separation technologies for the processing of formation fluid from the Achimov deposits

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Petroleum Research 2023年第3期8卷 413-423页

作者： Alexandra Saitova Sergey Strokin Falk Ahnert aleksandr Chepurnov Peter the Great St Petersburg Polytechnic University Politechnicheskaya str.29Saint Petersburg195251Russian Federation Wintershall Dea AG Friedrich-Ebert-Straße 160Kassel34119Germany Wintershall Dea Russia GmbH Reshetnikova str.14ASaint Petersburg196105Russian Federation

Three different technologies for the low-temperature separation(LTS)of gas condensate from the Achimov deposits in the Russian Urengoyskoe gas and condensate field were assessed using exergy analyses.The options examined included turbo-expansion and ejection.Thermomechanical exergy values were calculated for material streams and exergy losses and efficiencies were estimated for dedicated equipment used in the LTS.The lowest exergy loss of 4221.2 kW was obtained using turboexpansion and electricity cogeneration.The carbon release associated with each scenario was calculated while considering different production rates,technological parameters and natural decreases in wellhead pressure.The integral carbon footprint after 40 years of LTS operation was estimated for all cases.A classical ejector-based LTS scheme was shown to produce 1200 t of CO_(2)emissions over 40 years of operation.This same scheme combined with a turboexpander and electricity generator produced 59%less CO_(2)in the same period.An expansion-cogeneration LTS scheme was found to be the most effective and ecologically friendly among the various options based on this analysis.

关键词： Oil and gas field Gas condensate Carbon emission Carbon footprint Complex gas treatment unit

Consistency of Perfect Fluidity and Jet Quenching in Semi-Quark-Gluon Monopole Plasmas

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Chinese Physics Letters 2015年第9期32卷 25-30页

作者：徐杰谌廖劲峰 miklos Gyulassy Department of Physics Columbia University New York 10027 USA Physics Department and CeeM Indiana University Bloomington 47408 USA RIKeN BNL Research Center Bldg. 510A Brookhaven National Laboratory New York 11973 USA

We utilize a new framework, CUJeT3.0, to deduce the energy and temperature dependence of the jet trans- port parameter, q （e 〉 10 GeV, T）, from a combined analysis of available data on nudear modification factor and azimuthal asymmetries from high energy nuclear collisions at RHIC/BNL and LHC/CeRN. extending a previous perturbative-QCD based jet energy loss model （known as CUJeT2.0） with （2＋1）D viscous hydrody- namic bulk evolution, this new framework includes three novel features of nonperturbative physics origin; （i） the Polyakov loop suppression of color-electric scattering （aka ＇semi-QGP＇ of Pisarski et al.）, （ii） the enhancement of jet scattering due to emergent magnetic monopoles near Tc （aka ＇magnetic scenario＇ of Liao and Shuryak）, and Oii） thermodynamic properties constrained by lattice QCD data. CUJeT3.0 reduces to v2.0 at high tem- peratures T 〉400 MeV, while greatly enhances ~ near the QCD deconfinement transition temperature range. This enhancement accounts well for the observed elliptic harmonics of jets with pT 〉10 GeV. extrapolating our data-constrained q down to thermal energy scales, e-2 GeV, we find for the first time a remarkable consistency between high energy jet quenching and bulk perfect fluidity with η/s^T3/q^0.1 near To.

关键词： QGP QCD LHC

Galectin-3-centered paracrine network mediates cardiac inflammation and fibrosis upon β-adrenergic insult

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Science China(Life Sciences) 2023年第5期66卷 1067-1078页

作者： Guomin Hu Jimin Wu Huijun Gu Xiangning Deng Wenli Xu Shan Feng Shuaixing Wang Yao Song Zhengda Pang Xiuling Deng aleksandr e.Vendrov Nageswara R.Madamanchi Marschall S.Runge Xinyu Wang Youyi Zhang Han Xiao erdan Dong Department of Cardiology and Institute of Vascular Medicine Peking University Third HospitalNHC Key Laboratory of Cardiovascular Molecular Biology and Regulatory PeptidesKey Laboratory of Molecular Cardiovascular ScienceMinistry of EducationBeijing Key Laboratory of Cardiovascular Receptors ResearchResearch Unit of Medical Science Research Management/Basic and Clinical Research of Metabolic Cardiovascular DiseasesChinese Academy of Medical SciencesBeijing 100191China Department of Physiology and Pathophysiology Cardiovascular Research CenterSchool of Basic Medical SciencesXi’an Jiaotong University Health Science CenterXi’an 710061China Department of Internal Medicine Frankel Cardiovascular CenterUniversity of MichiganAnn ArborMI48109USA Academy for Advanced Interdisciplinary Studies Peking UniversityBeijing 100087China

Rapid over-activation of β-adrenergic receptors (β-AR) following acute stress initiates cardiac inflammation and injury by activating interleukin-18 (IL-18),however,the process of inflammation cascades has not been fully illustrated.The present study aimed to determine the mechanisms of cardiac inflammatory amplification following acute sympathetic activation.With bioinformatics analysis,galectin-3 was identified as a potential key downstream effector of β-AR and IL-18 activation.The serum level of galectin-3 was positively correlated with norepinephrine or IL-18 in patients with chest pain.In the heart of mice treated with β-AR agonist isoproterenol (ISO,5 mg kg^(-1)),galectin-3 expression was upregulated markedly later than IL-18 activation,and Nlrp3^(-/-)and Il18^(-/-)mice did not show ISO-induced galectin-3 upregulation.It was further revealed that cardiomyocyte-derived IL-18 induced galectin-3 expression in macrophages following ISO treatment.Moreover,galectin-3deficiency suppressed ISO-induced cardiac inflammation and fibrosis without blocking ISO-induced IL-18 increase.Treatment with a galectin-3 inhibitor,but not a β-blocker,one day after ISO treatment effectively attenuated cardiac inflammation and injury.In conclusion,galectin-3 is upregulated to exaggerate cardiac inflammation and injury following acute β-AR activation,a galectin-3 inhibitor effectively blocks cardiac injury one day after β-AR insult.

关键词： galectin-3 interleukin-18 β-adrenergic receptor macrophage inflammation fibrosis

Strain-Rate Dependency of a Unidirectional Filament Wound Composite under Compression

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Computer Modeling in engineering & Sciences 2023年第12期137卷 2149-2161页

作者： Stepan Konev Victor A.eremeyev Hamid M.Sedighi Leonid Igumnov Anatoly Bragov aleksandr Konstantinov Ayaulym Kuanyshova Ivan Sergeichev Skolkovo Institute of Science and Technologies Center for Materials TechnologiesMoscowRussia National Research Lobachevsky State University of Nizhny Novgorod Nizhny NovgorodRussia Dipartimento di Ingegneria Civile Ambientale e Architettura(DICAAR)Universitàdegli Studi di CagliariCagliari(CA)Italy Mechanical engineering Department Faculty of EngineeringShahid Chamran University of AhvazAhvazIran Drilling Center of excellence and Research Center Shahid Chamran University of AhvazAhvazIran

This article presents the results of experimental studies concerning the dynamic deformation and failure of a unidirectional carbon fiber reinforced plastic(T700/LY113)under compression.The test samples were manufactured through the filament winding of flat plates.To establish the strain rate dependencies of the strength and elastic modulus of the material,dynamic tests were carried out using a drop tower,the Split Hopkinson Pressure Bar method,and standard static tests.The samples were loaded both along and perpendicular to the direction of the reinforcing fiber.The applicability of the obtained samples for static and dynamic tests was confirmed through finite elementmodeling and the high-speed imaging of the deformation and failure of samples during testing.As a result of the conducted experimental studies,static and dynamic stress-strain curves,time dependencies of deformation and the stress and strain rates of the samples during compression were obtained.Based on these results,the strain rate dependencies of the strength and elasticity modulus in the strain rate range of 0.001-6001/s are constructed.It is shown that the strain rate significantly affects the strength and deformation characteristics of the unidirectional carbon fiber composites under compression.An increase in the strain rate by 5 orders of magnitude increased the strength and elastic modulus along the fiber direction by 42%and 50%,respectively.Perpendicular loading resulted in a strength and elastic modulus increase by 58%and 50%,respectively.The average strength along the fibers at the largest studied strain rate was about 1000MPa.The obtained results can be used to design structural elements made of polymer composite materials operating under dynamic shock loads,as well as to build models of mechanical behavior and failure criteria of such materials,taking into account the strain rate effects.

关键词： High strain rate composites filament winding dynamic strength Split Hopkinson Pressure Bar compression

Variable retention forestry in european boreal forests in Russia

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ecological Processes 2019年第1期8卷 424-434页

作者： ekaterina Shorohova Sergey Sinkevich aleksandr Kryshen Ilkka Vanha-Majamaa Forest Research Institute of the Karelian Research Centre of the Russian Academy of Sciences Pushkinskaya str.11Petrozavodsk 185910Russia Saint-Petersburg State Forest Technical University Institutsky str.5Saint Petersburg 194021Russia Natural Resources Institute Finland(Luke)Latokartanonkaari 9FI-00790 HelsinkiFinland

We explored whether,and to what extent,variable retention(VR)forestry has been applied in european boreal forests in northwestern Russia.Our survey revealed VR since 1910.Between 1910 and the 1960s,the statistics showing how much was retained are largely missing.However,for example,in the 1950s,on a large scale in the Republic of Karelia,up to 200-ha-sized harvesting areas,18–33%,were retention patches with a mean growing stock of 30–40m3 ha−1.In the fellings defined as“incomplete clear fellings,”which were the most common final felling type at that time,11–40%of the growing stock was left.Between the 1960s and the early 1990s,with more efficient harvesting and skidding techniques,conventional clear fellings with a much lower amount of retention were practiced.Concern about the regeneration of harvested areas gradually led to smaller(maximum 50 ha)harvesting areas and the increase of silvicultural activities.Until now,to ensure natural regeneration,patches of understory and 20–25 seed trees(i.e.,ca.15–25m3)per ha have been left permanently in harvesting areas.Landscape-scale retention for protecting ecosystem functions and biodiversity was legislated in 1978 by preserving key biotopes up to 1000 ha in size.Since 2001,promoted by forest certification,the key biotopes,such as paludified forest patches,buffers around water bodies,and habitats of red-listed species,have also been retained in harvesting areas,together with a dispersed retention of different elements.Quantitative estimates of the amount of key biotopes are largely missing.However,estimates of 1–13%in harvesting areas and 23%in whole managed landscapes have been given.VR applied during the last century has emulated natural disturbances and created diverse uneven-aged forest structures with high amounts of diverse coarse woody debris.We conclude that an analysis of past and current retention practices is essential for estimating the global role of Russian forestry.Further decisions on the general direction of Russian forestry and,specifically,retention p

关键词： Biological legacies Nature conservation Biodiversity Clear felling Key biotopes Coarse woody debris,Silviculture Dispersed and aggregated retention

Northwestward range expansion of the bumblebee Bombus haematurus into Central europe is associated with warmer winters and niche conservatism

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Insect Science 2021年第3期28卷 861-872页

作者： Paolo Biella Aleksandar Cetkovic Andrej Gogala Johann Neumayer miklos Sarospataki Peter Sima Vladimir Smetana Department of Biotechnology and Biosciences University of Milano-BicoccaMilanoItaly Faculty of Biology University of BelgradeBelgradeSerbia Department of Invertebrate Zoology Slovenian Museum of Natural HistoryLjubljanaSlovenia Obergrubstrafie ElixhausenAustria Department of Zoology and ecology Szent Istvan UniversityGodolloHungary Department of Research and Development Koppert s.r.o.Nove ZamkySlovakia Department of Natural History Tekov MuseumLeviceSlovakia

Species range expansions are crucial for understanding niche formation and the interaction with the environment.Here,we studied the bumblebee Bombus haematurus Kriechbaumer,1870,a species historically distributed from northern Serbia through northern Iran which has very recently started expanding northwestward into Central europe without human-mediated dispersal(i.e.,it is a natural spread).After updating the global distribution of this species,we investigated if niche shifts took place during this range expansion between newly colonized and historical areas.In addition,we have explored which climatic factors may have favored the natural range expansion of the species.Our results indicated that Bombus haematurus has colonized large territories in 7 european countries outside the historical area in the period from the 1980s to 2018,a natural expansion over an area that equals 20%of the historical distribution.In addition,this bumblebee performs generalism in flower visitation and it occurs in different habitats,although a preference for forested areas clearly emerges.The land-use associated with the species in the colonized areas is similar to the historical distribution,indicating that no major niche shifts occurred during the spread.Furthermore,in recently colonized localities,the range expansion was associated with warming temperatures during the winter and also during both queen overwintering and emergence phases.These findings document a case of natural range expansion due to environmental change rather than due to niche shifts,and specifically they suggest that warmer winters could be linked to the process of natural colonization of new areas.

关键词： climate change insect conservation niche conservatism niche shift pollinator range expansion

Negative thermal expansion in one-dimension of a new double sulfate AgHo(SO_(4))_(2)with isolated SO_4 tetrahedra

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Journal of Materials Science & Technology 2021年第17期76卷 111-121页

作者： Yuriy G.Denisenko Victor V.Atuchin Maxim S.Molokeev Naizheng Wang Xingxing Jiang aleksandr S.aleksandrovsky Alexander S.Krylov aleksandr S.Oreshonkov Alexander e.Sedykh Svetlana S.Volkova Zheshuai Lin Oleg V.Andreev Klaus Müller-Buschbaum Institute of Chemistry Tyumen State University.Tyumen625003Russia Institute of Inorganic and Analytical Chemistry Justus-Liebig-University of Giessen35392Giessen.Germany Department of General and Special Chemistry Industrial University of TyumenTyumen625000Russia Laboratory of Optical Materials and Structures Institute of Semiconductor PhysicsSB RASNovosibirsk630090Russia Laboratory of Semiconductor and Dielectric Materials Novosibirsk State UniversityNovosibirsk630090Russia Research and Development Department.Kemerovo State University Kemerovo650000Russia Laboratory of Crystal Physics Kirensky Institute of PhysicsFederal Research Center KSC SB RASKrasnoyarsk660036Russia Siberian Federal University Krasnoyarsk660041Russia Department of Physics Far Eastern State Transport UniversityKhabarovsk680021Russia Technical Institute of Physics and Chemistry Chinese Academy of SciencesBeijing100190China Laboratory of Coherent Optics Kirensky Institute of Physics.Federal Research Center KSC SB RASKrasnoyarsk660036Russia Institute of Nanotechnology Spectroscopy and Quantum ChemistrySiberian Federal UniversityKrasnoyarsk660041Russia Laboratory of Molecular Spectroscopy Kirensky Institute of PhysicsFederal Research Center KSC SB RASKrasnoyarsk660036Russia Center for Materials Research(LaMa) Justus-Liebig-University GiessenGiessen35392Germany University of the Chinese Academy of Sciences Beijing100049China Laboratory of the Chemistry of Rare earth Compounds Institute of Solid State ChemistryUB RASEkaterinburg620137Russia

A double holmium-silver sulfate was obtained for the first time.The temperature intervals for the formation and stability of the compound were determined by differential scanning calorimetry.The crystal structure of AgHo(SO_(4))_(2)was determined by Rietveld method.The X-ray diffraction(XRD)analysis showed that the compound crystallizes in the monoclinic syngony,space group P2_1/m,with the unit cell parameters a=4.71751(4)A,b=6.84940(6)A and c=9.89528(9)A,β=95.1466(4)·,V=318.448(5)A^(3),Z=2,R_B=1.55%,T=303 K.Two types of sulfate tetrahedra were found in the structure,which significantly affected the spectral properties in the infrared range.In the temperature range of 143-703 K,a negative thermal expansion along the b direction accompanied by a positive thermal expansion along the a and c directions was observed.It was established that negative thermal expansion is the result of the deformation of sulfate tetrahedra,which is affected by the movement of holmium and silver atoms.The excitation in the blue spectral range(457.9 nm)produces a luminescence in light blue(489 nm),green(545 nm)and red(654 nm)spectral ranges,and the latter two were of comparable intensity that is favorable for WLeD sources.The observed luminescent band distribution is ascribed to the specific crystal field at Ho^(3+)ion sites rather than a variation of radiationless probability.

关键词： Sulfate Crystal structure Thermal expansion Raman Photoluminescence Band structure