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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 *** 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 ***-doped fibers are of increasing interest as gain materials,which can be used to provide broadband amplification in the mentioned telecom *** 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 *** 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)*** Bi-to-BACs conversion efficiency in various spatial regions of the studied samples is *** 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 ***,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

Individual alcohol consumption by the population of Russia versus regional living conditions

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Global Health Journal 2024年第1期8卷 24-31页

作者： sergey A.Maksimov Svetlana A.Shalnova Galina A.Muromtseva Yuliya A.Balanova Svetlana E.Evstifeeva Anna V.Kapustina Oksana M.Drapkina National Medical Research Center for Therapy and Preventive Medicine Moscow 101990Russia

Background:There are substantial regional differences in drinking alcohol in Russia,both at the population and individual ***,the causes of these differences have not been studied ***:The goal of our study was to examine the effect of regional living conditions on individual alcohol consumption by the population of ***:For the analysis,we used data from a cross-sectional epidemiological study conducted in *** final analytical sample included 18,130 people aged 25-64 *** conducted the interviews face to face,based on which any drinking in the last year,as well as alcohol abuse,were considered as a *** abuse was recorded when the respondent consumed 5.75 or more grams of pure ethanol per day(75th percentile of average daily alcohol consumption among alcohol drinkers).The assessment of the regional living conditions was accomplished via integral indexing,which was previously performed based on publicly available data for *** were assessed using generalized scoring equations with unchanging standard *** associations were expressed by odds ratios(OR)and 95%confidence intervals(C).Results:Deterioration of social conditions and increase in demographic depression in the region of residence increased the odds of any drinking(OR 1.51,95%CI:1.33 to 1.72,P<0.001 and OR 1.22,95%CI:1.05 to 1.41,P=***9,respectively).The odds of alcohol abuse increased with the deterioration of social living conditions and the growth of the industrial development in the region:OR 1.35,95%CI:1.14 to 1.59,P<0.001 and OR 1.16,95%CI:1.05 to 1.28,P=0.002,***:Our analysis allowed assessing the impact of the regional living conditions on individual drinking alcohol in the population of Russia.

关键词： Alcohol Living environment Regional features Russia

农村劳动力转移对耕地利用可持续集约化的影响

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农业工程学报 2024年

作者：陈梦涵吕晓 sergey Yu.Solodovnikov TATSIANA V.Serhiyevich 东北大学文法学院白俄罗斯国立技术大学

厘清农村劳动力转移与耕地利用可持续集约化之间的关系对于促进农业可持续发展具有重要意义。该研究基于1990—2020年中国省级面板数据，采用超效率SBM模型测算耕地利用可持续集约化水平，运用面板门槛模型探讨农村劳动力转移对耕地利... 详细信息

厘清农村劳动力转移与耕地利用可持续集约化之间的关系对于促进农业可持续发展具有重要意义。该研究基于1990—2020年中国省级面板数据，采用超效率SBM模型测算耕地利用可持续集约化水平，运用面板门槛模型探讨农村劳动力转移对耕地利用可持续集约化的影响效应。结果表明：1)1990—2020年中国耕地利用可持续集约化水平总体呈先下降后上升的趋势，区域间差异显著；2）农村劳动力转移对耕地利用可持续集约化存在非线性影响，当农村劳动力转移水平小于0.351时，农村劳动力转移不利于耕地利用可持续集约化的增长；超过这一门槛后，农村劳动力转移对耕地利用可持续集约化产生显著的增长效应；3）农村劳动力转移对耕地利用可持续集约化的影响存在非均衡效应，即农村劳动力转移对农业发达地区与平原地区的促进作用显著，但对农业欠发达地区与山地地区的促进作用尚不显著。基于此，应合理引导农村冗余劳动力非农转移，以推动耕地利用可持续集约化转型；同时，应注意耕地利用可持续集约化提升的自然环境禀赋与农业经济发展水平制约，因地制宜的探索适宜地区条件的耕地利用可持续集约化发展路径。

关键词：农村劳动力转移耕地利用可持续集约化超效率SBM模型门槛模型非均衡效应

Telluric iron assemblages as a source of prebiotic phosphorus on the early Earth:Insights from Disko Island,Greenland

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Geoscience Frontiers 2024年第5期15卷 415-429页

作者： Oleg S.Vereshchagin Maya O.Khmelnitskaya Larisa V.Kamaeva Natalia S.Vlasenko Dmitrii V.Pankin Vladimir N.Bocharova sergey N.Britvin Saint Petersburg State University University Embankment 7-9St.Petersburg 199034Russia Udmurt Federal Research Center Ural BranchRussian Academy of SciencesIzhevsk 426067Russia Nanomaterial Research Center Kola Science CentreRussian Academy of SciencesApatity 184209Russia

Phosphorus is one of the key elements,which determined the emergence of primordial life on our *** source of prebiotic phosphorus was most likely to be easily soluble compounds containing phosphorus in the negative form of oxidation(e.g.,phosphides).The present paper is the first thorough investigation of phosphide-bearing mineral assemblages confined to telluric(terrestrial)native iron from volcanic rocks of Disko Island,*** speciation in given assemblages varies from the solid solution in native iron(up to 0.3 wt.%P),different phosphides–schreibersite Fe_(3)P,nickelphosphide Ni_(3)P,barringerite Fe_(2)P,and phosphates,including fluorapatite,anhydrous Fe-Na phosphates,phosphoran olivine and pyroxene(up to 1 wt.%P).The diversity of observed phosphorus speciation can be explained by the steep changes of redox conditions during subsurface crystallization of iron-phosphide-bearing *** on the available data on likely redox conditions on the early Earth,we hypothesize that reactive prebiotic phosphorus may have originated from shallow crustal rocks.

关键词： Prebiotic phosphorus Native iron Phosphide Reduced mineral assemblages

A rare case of cardiac and ophthalmic manifestations of meningococcal septicemia

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World Journal of Emergency Medicine 2024年第4期15卷 328-330页

作者： Svetlana Rachina Anastasia Shchendrygina Heshan Radeesha de Silva Svetlana Tarasenko Nadezhda Mukhina Irina Komarova Ludmila Fedina Elena Burmistrova Elvira Martens sergey Sidorenko Vladimir Gostev Dmitry Polev Alina Saitova Lyudmila Kraeva Nikita Goncharov Irina Zvetkova Department of Hospital Therapy I M Sechenov First Moscow State Medical UniversityMoscow 119048Russia Outpatient Clinic#64 Moscow 119048Russia Department of Cardiology City Clinical Hospital n.a.S.S.YudinMoscow 119048Russia Department of Medical Microbiology and Molecular Epidemiology Pediatric Research and Clinical Center for InfectiousDiseasesSaint Petersburg 197022Russia Department of Medical Microbiology North-Western State Medical University Named After I.I.MechnikovSaintPetersburg 191015Russia Department of Epidemiology Saint-Petersburg Pasteur InstituteSaint Petersburg 197101Russia

Acute pericarditis is usually a self-limiting disorder that commonly occurs due to viral etiology or unexplained *** pericarditis(MP)is a remarkably uncommon clinical entity that manifests as a complication during the acute or convalescent phase of meningococcal ***,its occurrence within the context of meningococcal septicemia has also been *** report a rare case of a previously healthy male patient who developed both acute pericarditis and uveitis as a presentation of meningococcal septicemia,with no characteristic skin rashes or meningeal signs.

关键词： acute Acute rare

The effect of long-term application of nitrogen-rich fertilizers on soil resistome:A study of conventional and organic cropping systems

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Soil Ecology Letters 2024年第3期6卷 135-150页

作者： Alexey S.Vasilchenko Evgenii O.Burlakov Darya V.Poshvina Denis S.Gruzdev sergey V.Kravchenko Aleksandr V.Iashnikov Ning Ling Anastasia V.Vasilchenko Laboratory of Antimicrobial Resistance Institute of Environmental and Agricultural Biology(X-BIO)Tyumen State UniversityTyumenRussia Research Institute of Mathematics Physics and Computer ScienceDerzhavin Tambov State UniversityTambovRussia International Integrated Research Laboratory for Climate Change Land Use and BiodiversityInstitute of Environmental and Agricultural Biology(X-BIO)Tyumen State UniversityTyumenRussia SciBear OU Tartu Mnt 67/1-13bKesklinna Linnaosa10115 TallinnEstonia Center for Grassland Microbiome State Key Laboratory of Grassland Agro-EcosystemsCollege of Pastoral Agriculture Science and TechnologyLanzhou UniversityLanzhou 730000China

Metagenomic studies of various soil environments have previously revealed the widespread distribution of antibiotic resistance genes(ARGs)around the *** this study,we applied shotgun metagenomics to investigate differences in microbial communities and resistomes in Chernozem soils that have been under long-term organic and conventional cropping *** organic cropping system was seeded with Triticum spelta without any *** conventional cropping system was seeded with Tríticum durum Desf and used mineral fertilizer(NPK),that resulted in an increased amount of total and available carbon and nitrogen in *** all samples,we identified a total of 21 ARG classes,among which the dominant were vancomycin,tetracycline and *** of soil microbial communities revealed differences between the studied fields in the relative abundances of 14 and 53 genera in topsoil and subsoil,*** analysis showed significant correlations(positive and negative)among 18 genera and 6 ARGs,as well as between these ARGs and some chemical properties of *** analysis of metagenome-assembled genomes revealed that Nitrospirota,Thermoproteota,Actinobacteriota and Binatota phyla of archaea and bacteria serve as hosts for glycopeptide and fluoroquinolone/tetracycline ***,the data obtained enrich knowledge about the consequences of human agricultural activities in terms of soil microbiome modification and highlight the role of nitrogen cycling taxa,including uncultivated genera,in the formation of soil resistome.

关键词： soil microbiome inorganic fertilizer nitrogen cycle uncultured bacteria chemolithotrophs Binatia

Recent Ventures in Interdisciplinary Arctic Research:The ARCPATH Project

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Advances in Atmospheric Sciences 2024年第8期41卷 1559-1568页

作者： Astrid E.J.OGILVIE Leslie A.KING Noel KEENLYSIDE François COUNILLON Brynhildur DAVIÐSDÓTTIR Níels EINARSSON sergey GULEV Ke FAN Torben KOENIGK James R.MCGOODWIN Marianne H.RASMUSSON Shuting YANG Institute of Arctic and Alpine Research(INSTAAR) University of ColoradoBoulder CO 80303USA Stefansson Arctic Institute AkureyriÍS-600Iceland Royal Roads University BC V9B 5Y2Canada University of Bergen Bergen N-5007Norway Nansen Environmental and Remote Sensing Centre Bergen N-5007Norway University of Iceland Reykjavík 102Iceland Shirshov Institute of Oceanology Moscow 117218Russia Moscow State University Moscow 11991Russia Chinese Academy of Sciences Beijing 100045China Swedish Meteorological and Hydrological Institute SE-60176 NorrköpingSweden Danish Meteorological Institute CopenhagenØ2100Denmark Obukhov Institute of Atmospheric Physics RAS119017MoscowRussia

This paper celebrates Professor Yongqi GAO's significant achievement in the field of interdisciplinary studies within the context of his final research project Arctic Climate Predictions: Pathways to Resilient Sustainable Societies-ARCPATH(https://***/en/projects/finished-projects/arcpath). The disciplines represented in the project are related to climatology, anthropology, marine biology, economics, and the broad spectrum of social-ecological studies. Team members were drawn from the Nordic countries, Russia, China, the United States, and Canada. The project was transdisciplinary as well as interdisciplinary as it included collaboration with local knowledge holders. ARCPATH made significant contributions to Arctic research through an improved understanding of the mechanisms that drive climate variability in the Arctic. In tandem with this research, a combination of historical investigations and social, economic, and marine biological fieldwork was carried out for the project study areas of Iceland, Greenland, Norway, and the surrounding seas, with a focus on the joint use of ocean and sea-ice data as well as social-ecological drivers. ARCPATH was able to provide an improved framework for predicting the near-term variation of Arctic climate on spatial scales relevant to society, as well as evaluating possible related changes in socioeconomic realms. In summary, through the integration of information from several different disciplines and research approaches, ARCPATH served to create new and valuable knowledge on crucial issues, thus providing new pathways to action for Arctic communities.

关键词： Recent Ventures in Interdisciplinary Arctic Research:The ARCPATH Project

氧同位素3早期以来千年尺度气候事件在日本海北部的磁学记录

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海洋学报 2024年第4期46卷 106-121页

作者：邹庆超石学法葛淑兰吴永华邹建军贺湘锋 sergey A.Gorbarenko 刘建兴自然资源部第一海洋研究所海洋地质与成矿作用自然资源部重点实验室山东青岛266061 青岛海洋科技中心海洋地质过程与环境功能实验室山东青岛266237 南京大学地理与海洋科学学院江苏南京210023 俄罗斯科学院远东分院太平洋研究所俄罗斯符拉迪沃斯托克690041

日本海是西北太平洋最大的边缘海,长期以来普遍认为其沉积物处于强烈的还原环境中而导致相应的磁学信号非常微弱,以致常用的磁学方法在该区的应用一直受限。为深入探讨磁学指标在日本海古环境与古海洋学研究中是否有效,本文对位于研究... 详细信息

日本海是西北太平洋最大的边缘海,长期以来普遍认为其沉积物处于强烈的还原环境中而导致相应的磁学信号非常微弱,以致常用的磁学方法在该区的应用一直受限。为深入探讨磁学指标在日本海古环境与古海洋学研究中是否有效,本文对位于研究程度相对薄弱的北部一根626 cm长的柱状沉积物岩心(LV87-2-3孔,水深740 m)开展了系统的岩石磁学测试分析以及高分辨率的AMS14C测年和粒度分析。结果显示岩心系约48.3 ka BP以来的沉积记录,其55 cm以下层位的原生亚铁磁性矿物(主要为磁铁矿)已被大量还原而生成黄铁矿,导致磁性极弱。这与Dansgaard-Oeschger(D-O)旋回间冰阶水体分层加强和表层生产力提高等因素密切相关。然而,在此背景下仍存在4个以高矫顽力矿物(如赤铁矿和针铁矿)占比较高为明显特征的强磁性层位,即“硬磁异常”层;其很好地对应了海因里希(Heinrich)事件,指示了东亚冬季风(EAWM)增强和高盐度对马暖流(TWC)注入而导致的相对减弱的还原环境。上述变化在沉积物粒度上却未见清晰体现。因此,该研究不仅表明磁学参数对于指示末次冰期日本海古海洋与古环境演化的作用不容忽视,同时也为后续相关工作提供了新视角和新思路。

关键词：日本海沉积物磁性矿物岩石磁学古环境 Heinrich事件

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利用大数据提高机器人的能力

科技纵览 2024年第2期 44-48,4页

作者： sergey Levine Karol Hausman 不详

一系列机器人,一系列任务。在现实世界中变得普遍有用之前,机器人还有很多东西要学。虽然过去几年里,人工智能通过互联网这个庞大数据集的训练取得了令人印象深刻的进步,但机器人还没有类似的大型物理数据集可以利用。我们与世界各地的... 详细信息

一系列机器人,一系列任务。在现实世界中变得普遍有用之前,机器人还有很多东西要学。虽然过去几年里,人工智能通过互联网这个庞大数据集的训练取得了令人印象深刻的进步,但机器人还没有类似的大型物理数据集可以利用。我们与世界各地的其他32家机器人实验室合作,创建了现有最大的真实机器人动作开源数据集,对22种机器人进行了近100万次机器人试验,其中包含500种不同的技能以及与数干个不同对象的交互,包括图中的示例。

关键词：机器人人工智能物理数据大数据互联网数据集开源数据交互