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Assessment of the state of Forests Based on Joint statistical Processing of sentinel-2B Remote sensing Data and the Data from Network of Ground-Based ICP-Forests sample Plots

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Open Journal of Ecology 2022年第8期12卷 513-528页

作者： Alexander s. alekseev Dmitry M. Chernikhovskii Department of Forest Inventory Management and GIS Saint-Petersburg State Forest Technical University Saint-Petersburg Russian Federation

The research was carried out on the territory of the Karelian Isthmus of the Leningrad Region using sentinel-2B images and data from a network of ground sample plots. The ground sample plots are located in the studied territory mainly in a regular manner, laid and surveyed according to the ICP-Forests methodology with some additions. The total area of the sample plots is a small part of the entire study area. One of the objectives of the study was to determine the possibility of using the k-NN (nearest neighbor method) to assess the state of forests throughout the whole studied territory by joint statistical processing of data from ground sample plots and sentinel-2B imagery. The data of the ground-based sample plots were divided into 2 equal parts, one for the application of the k-NN method, the second for checking the results of the method application. The systematic error in determining the mean damage class of the tree stands on sample plots by the k-NN method turned out to be zero, the random error is equal to one point. These results offer a possibility to determine the state of the forest in the entire study area. The second objective of the study was to examine the possibility of using the short-wave vegetation index (sWVI) to assess the state of forests. As a result, a close statistically reliable dependence of the average score of the state of plantations and the value of the sWVI index was established, which makes it possible to use the established relationship to determine the state of forests throughout the studied territory. The joint use and statistical processing of remotely sensed data and ground-based test areas by the two studied methods make it possible to assess the state of forests throughout the large studied area within the image. The results obtained can be used to monitor the state of forests in large areas and design appropriate forestry protective measures.

关键词： Remote sensing sentinel-2B Imagery ICP-Forest sample Plot Tree stand Damage Class k-NN (Nearest Neighbor Method) Vegetation Index sWVI Nonlinear Regression systematic Error Random Error

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Assessment and Inventory of Forest Ecosystems Biodiversity: Case study for Karelian Isthmus of Leningrad Region, Russia

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Open Journal of Ecology 2018年第5期8卷 305-323页

作者： Alexander s. alekseev Department of Forest Inventory Management and GIS Sankt-Petersburg State Forest Technical University Sankt-Petersburg Russia

Regular grid of permanent sample plots (PsP) of ICP-Forests monitoring system was used for forest ecosystems biodiversity assessments and inventory. The supplementary features were added to the PsP structure to conduct biological diversity census: eight sample plots 1 × 1 m for geo-botanical description;two sample plots of 5 × 5 m each for description of the PsP’s undergrowth;one 25 × 25 m plot for coarse woody debris estimations;four soil inventory pits. The total number of PsP amounted to 248. Total data used are as following: 1) 1984 geo-botanical descriptions of vegetation belonging to ground cover layers made on 1 × 1 m sample plots;2) 496 descriptions of undergrowth on 5 × 5 m sample plots;3) 178 descriptions of woody debris on 25 × 25 m sample plots;4) 496 descriptions of soil inventory pits. General statistical indicators characterizing forest land cover diversity were calculated. statistic indicators of α-diversity for the Karelian Isthmus forest vegetation cover have the following values: 1) m (mean number of species per PsP) = 26 species;2) σ (standard deviation) = 9.5 species;3) v (variation coefficient) = 36.5%;4) Р (deviation amplitude) = 60 – 7 = 53 species. β – diversity of forest ecosystems as well as γ – diversity also was studied on the base of information collected on the same regular grid of sample plots. It appears that sample plots distribution by species diversity gradation is well described by the standard curve of normal distribution for the entire Karelian Isthmus forest (determination coefficient of the curve being 95.2%) as well as for each type of forest. Hence, the criterion (standard) of biodiversity for forest ecosystems can be defined as the mean value of alpha diversity for each forest type group – m;and the standard deviation – σ, as a tool for assessing deviations from the standard. PsP locations are fixed using GPs technology, this allows biodiversity assessments at the same place in the next years for biodiversity trends estima

关键词： Plant Biodiversity ICP-Forests Program Forest Ecosystems α- β- γ-Diversity Regular Grid of sample Plots Biodiversity standards.

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Detection and clearance in Alzheimer’s disease: leading with illusive chemical, structural and morphological features of the targets

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Neural Regeneration Research 2024年第3期19卷 497-498页

作者： Luís Gales i3s−Instituto de Investigação e Inovação em saúde Rua Alfredo AllenPortoPortugal(Gales L)IBMC−Instituto de Biologia Molecular e CelularUniversidade do PortoRua Alfredo AllenPortoPortugal ICBAs−Instituto de Ciências Biomédicas Abel salazar Rua de Jorge Viterbo FerreiraPortoPortugal

Highly specific interactions between biomolecules,such as antigen-antibody,protein-ligand,or nucleic acid base pair complementary are on the basis of the organization of complex *** same principles may be tentatively used in molecular medicine for diagnosis and therapeutics.A molecule can be designed to selectively bind a protease and thereby inhibit the production of a peptide that forms toxic aggregates in the brain or an antibody may be produced to bind specifically to that peptide for detection or clearance ***,interference in biological systems is not that *** a start there is the inhibition of the physiological role of the protease;moreover,several cleavage fragments may be produced,which may continue to diverge due to putative post-translational modification and self-assembly processes,hiding the toxic target in a“soup”of peptide species varying in size,structure and chemical composition.A perspective of the current status and challenges in targeting peptide species for diagnosis and treatment in the context of Alzheimer’s disease is given.

关键词： Alzheimer diagnosis thereby

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基于XeF(C-A)放大器的混合(固态/气态)超高功率飞秒激光系统(英文)

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光学精密工程 2011年第2期19卷 252-259页

作者： LOsEV V alekseev s IVANOV N KOVALCHUK B MIKHEEVL MEsYATs G PANCHENKO Yu PUCHIKIN A RATAKHIN N YAsTREMsKY A Institute of High Current Electronics of siberian Branch of Russian Academy of sciences aveAkademichesky 2/3Tomsk 634055Russia Lebedev Physical Institute of Russian Academy of sciences Leninsky Prospekt53119991 Russia

提出了基于前端发生器和终端放大器,使用光泵浦XeF（C-A）激活介质的太瓦级混合激光器（THL-100）系统。前端发生器由长532 nm的连续激光泵浦的钛宝石飞秒脉冲振荡器,脉冲展宽机构,532 nm的脉冲激光泵浦的再生多通道放大器,衍射光栅压... 详细信息

提出了基于前端发生器和终端放大器,使用光泵浦XeF（C-A）激活介质的太瓦级混合激光器（THL-100）系统。前端发生器由长532 nm的连续激光泵浦的钛宝石飞秒脉冲振荡器,脉冲展宽机构,532 nm的脉冲激光泵浦的再生多通道放大器,衍射光栅压缩器和二次谐波发生器（KDP）组成。其光束输出参数为：脉冲持续时间50 fs,二次谐波（475 nm）辐射能量5 mJ。前端发生器以10 Hz的单脉冲模式工作。XeF（C-A）放大器由双高压脉冲发生器（线性变压器）,爆炸式阴极发射真空二极管,电子束注入系统,充满Xe的气室转换器和激光单元组成。高压发生器包括12个变压器,每个变压器有8个电容（40 nF）和火花隙,电容可以充电至100 kV。真空二极管中的电子束参数为：总电流300 kA,峰值电压550kV,脉冲持续时间约150 ns。穿透金属箔片到达Xe转换器的6个100 cm×12 cm电子束的总能量为67 kJ。激光系统通过泵浦能量的级联处理导致Xe2＊的快速形成,并在（172±5）nm连续辐射。真空紫外辐射通过CaF2窗口辐射到含有XeF2蒸汽和氮气缓冲气体的激光单元中,使XeF2光解,形成XeF＊准分子。由真空紫外辐射泵浦的放大器激活介质长110 cm,直径为24 cm。文中通过数值模拟给出了输出参数和第一实验结果,根据XeF（C-A）放大器参数模型和增益测量结果,得到的输出能量高达23 J,这意味着50 fs脉冲的峰值功率高达4060 TW。

关键词：混合激光器 XeF(C—A)放大器飞秒脉冲宽度电子束紫外转换器

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等离子体技术制备具有亚微米颗粒结构的球化W-Cu伪合金微粉

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Transactions of Nonferrous Metals society of China 2024年第2期34卷 592-603页

作者： A.V.sAMOKHIN N.V.alekseev A.A.DOROFEEV A.A.FADEEV M.A.sINAYsKIY I.D.ZAVERTIAEV Y.V.GRIGORIEV Institute of Metallurgy and Materials science Russian Academy of SciencesMoscow 119334Leninsky prospect 49Russian Federal scientific Research Center“Crystallography and Photonics” Russian Academy of SciencesMoscow 119334Leninsky prospect 59Russian

采用复杂多级方法研究并证实制备具有亚微米/纳米级内部结构的球形W-Cu复合微粉的可能性。首先,采用等离子体化学合成法制备具有核壳结构的W-Cu纳米粉末(W核及Cu壳)。然后,将W-Cu纳米粉末与蔗糖的水悬浮液进行喷雾干燥,形成25~63μm的微... 详细信息

采用复杂多级方法研究并证实制备具有亚微米/纳米级内部结构的球形W-Cu复合微粉的可能性。首先,采用等离子体化学合成法制备具有核壳结构的W-Cu纳米粉末(W核及Cu壳)。然后,将W-Cu纳米粉末与蔗糖的水悬浮液进行喷雾干燥,形成25~63μm的微粒,收率为50%。最后,用热等离子体射流处理由纳米粉末组成的微粒,形成致密的球形W-Cu颗粒。成品粉末的球化度为90%~95%,体积密度为8.1 g/cm^(3),流动性约为12 s/50 g,杂质中O、C和H的含量(质量分数)分别为0.7%、0.02%~0.2%和0.03%~0.05%。

关键词： W-Cu复合材料等离子体化学合成造粒等离子体球化纳米颗粒微粒微粉

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Photonuclear reactions on stable isotopes of selenium at bremsstrahlung end-point energies of 10-23 MeV

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Chinese Physics C 2024年第2期48卷 91-103页

作者： F.A.Rasulova N.V.Aksenov s.I.alekseev R.A.Aliev s.s.Belyshev I.Chuprakov N.Yu.Fursova A.s.Madumarov J.H.Khushvaktov A.A.Kuznetsov B.s.Yuldashev Joint Institute for Nuclear Research DubnaRussia Institute of Nuclear Physics of the Academy of sciences of the Republic of Uzbekistan TashkentUzbekistan Faculty of Chemistry of Lomonosov Moscow state University MoscowRussia National Research Center"Kurchatov Institute" MoscowRussia skobeltsyn Institute of Nuclear Physics of Lomonosov Moscow state University MoscowRussia Faculty of Physics of Lomonosov Moscow state University MoscowRussia Institute of Nuclear Physics AlmatyRepublic of Kazakhstan

In this study,experiments were performed at bremsstrahlung end-point energies of 10-23 MeV with the beam from the MT-25 microtron using theγ-activation *** experimental values of relative yields were compared with theoretical results obtained on the basis of TALYs with the standard parameters and the combined model of photonucleon *** isospin splitting in the combined model of photonucleon reactions allows describing experimental data on reactions with proton escape in the energy range from 10 to 23 ***,taking into account isospin splitting is necessary for a correct description of the decay of the giant dipole resonance.

关键词： bremsstrahlung photon cross section isospin splitting giant dipole resonance

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多学科地震预报研究中的地球物理联合反演问题

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世界地震译丛 1996年第4期27卷 1-10页

作者： A.s.alekseev 平建军李文英张青荣河北省地震局

对震源区岩石破裂用扩容物理数学模型求定岩石强度和破裂的整体的临界参数(前兆)的方法已发展起来了。这个参数就是单位体积裂纹的密度。根据监测到的不同性质的地球物理场的异常变化数据和联合多学科反演问题的数值解,可对这一组合前... 详细信息

对震源区岩石破裂用扩容物理数学模型求定岩石强度和破裂的整体的临界参数(前兆)的方法已发展起来了。这个参数就是单位体积裂纹的密度。根据监测到的不同性质的地球物理场的异常变化数据和联合多学科反演问题的数值解,可对这一组合前兆进行定期判定。为多学科地震预报研究考虑了联合地球物理反演问题的一些具体例子。

关键词：地震预报地球物理联合反演

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Astrophysical s-factor and reaction rate for 15N(p,γ)16O within the modified potential cluster model

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Chinese Physics C 2024年第4期48卷 130-145页

作者： s.B.Dubovichenko A.s.Tkachenko R.Ya.Kezerashvili N.A.Burkova B.M.Yeleusheva Fesenkov Astrophysical Institute 050020 AlmatyKazakhstan New York City College of Technology City University of New YorkBrooklyn11201 New YorkUSA Graduate school and University Center City University of New York10016 New YorkUSA al-Farabi Kazakh National University 050040 AlmatyKazakhstan

We study radiative p^(15)N capture on the ground state of ^(16)O at stellar energies within the framework of a modified potential cluster model(MPCM)with forbidden states,including low-lying *** investigation of the ^(15)N(p,γ0)^(16)O reaction includes the consideration of ^(3)s_(1) resonances due to E1 transitions and the contribution of the ^(3)P_(1) scattering wave in the p+^(15)N channel due to the ^(3)P_(1)→^(3)P_(0)M1 *** calculated the astrophysical low-energy s-factor,and the extrapolated s(0)turned out to be within 34.7−40.4 keV·*** important role of the asymptotic constant(AC)for the ^(15)N(p,γ0)16O process with interfering ^(3)s_(1)(312)and ^(3)s_(1)(962)resonances is elucidated.A comparison of our calculation for the s-factor with existing experimental and theoretical data is addressed,and a reasonable agreement is *** reaction rate is calculated and compared with the existing *** has negligible dependence on the variation of AC but shows a strong impact of the interference of ^(3)s_(1)(312)and ^(3)s_(1)(962)resonances in reference to the CNO Gamow windows,especially at low *** estimate the contribution of cascade transitions to the reaction rate based on the exclusive experimental data from ***.C.85,065810(2012).The reaction rate enhancement due to the cascade transitions is observed from T_(9)>0.3 and reaches the maximum factor~1.3 at T_(9)=*** present the Gamow energy window and a comparison of rates for radiative proton capture reactions ^(12)N(p,γ)^(13)O,^(13)N(p,γ)^(14)O,^(14)N(p,γ)^(15)O,and ^(15)N(p,γ)^(16)O obtained in the framework of the MPCM and provide the temperature windows,prevalence,and significance of each process.

关键词： low and astrophysical energies p^(15)N system thermonuclear reaction rate potential cluster model CNO-cycle

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Choice of conodont Idiognathodus simulator （sensu stricto） as the event marker for the base of the global Gzhelian stage （Upper Pennsylvanian series, Carboniferous system）

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Episodes 2008年第3期31卷 319-325页

作者： Philip H. Heckel Aleksandr s. alekseev James E. Barrick Darwin R. Boardman Natalya V. Goreva Tatiana N. Isakova Tamara I. Nemyrovska Katsumi Ueno Elisa Villa David M. Work Department of Geoscience University of Iowa Iowa City Iowa 52242 USA Department of Paleontology Geology Faculty Moscow State University 119992 Moscow Russia Department of Geosciences Texas Tech University Lubbock Texas 79409 USA school of Geology Oklahoma State University Stillwater Oklahoma 74078 USA Geological Institute Russian Academy of Sciences Pyzhevsky per. 7 110017 Moscow Russia Institute of Geological sciences National Academy of Sciences of Ukraine O. Gonchar Str. 55b 01054 Kiev Ukraine Department of Earth system science Faculty of Science Fukuoka University Fukuoka 814-0180 Japan Department of Geology University of Oviedo Arias de Velasco s/n 33005 Oviedo Spain Maine state Museum 83 State House Station Augusta Maine 04333 USA

We propose that the level at which the conodont species Idiognathodus simulator (Ellison 1941) (sensu stricto) first appears be selected to mark the base of the Gzhelian stage, because we believe that this is the optimal level by which this boundary can be correlated This taxon has a short range and a wide distribution, as shown by correlation of glacial-eustatic cyclothems across the Kasimovian-Gzhelian boundary interval among Midcontinent North America and the Moscow and Donets basins of eastern Europe, based on scale of the cyclothems along with several aspects of biostratigraphy. Outside of these areas, I. simulator (sensu stricto) is known also from other parts of the U.s., and is reported from the southern Urals and south-central China in its expected position between other widespread taxa. Its first appearance is consistent with the current ammonoid placement of the boundary (first appearance of shumardites cuyleri), and it is also compatible with certain aspects of the distribution of Eurasian fusulinid faunas (e.g., lectotype of Rauserites rossicus).

关键词：牙形石奇颚牙形石属模拟技术岩石学

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The autophagy protein Atg9 functions in glia and contributes to parkinsonian symptoms in a Drosophila model of Parkinson’s disease

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Neural Regeneration Research 2024年第5期19卷 1150-1155页

作者： shuanglong Yi Linfang Wang Margaret s.Ho shiping Zhang school of Life science and Technology ShanghaiTech UniversityShanghaiChina College of Life sciences University of Chinese Academy of SciencesBeijingChina

Parkinson’s disease is a progressive neurodegenerative disease characterized by motor deficits,dopaminergic neuron loss,and brain accumulation ofα-synuclein aggregates called Lewy *** in protein degradation pathways,such as autophagy,has been demonstrated in neurons as a critical mechanism for eliminating protein aggregates in Parkinson’s ***,it is less well understood how protein aggregates are eliminated in glia,the other cell type in the *** the present study,we show that autophagy-related gene 9(Atg9),the only transmembrane protein in the autophagy machinery,is highly expressed in Drosophila glia from adult *** from immunostaining and live cell imaging analysis reveal that a portion of Atg9 localizes to the trans-Golgi network,autophagosomes,and lysosomes in ***9 is persistently in contact with these *** glial atg9 reduces the number of omegasomes and autophagosomes,and impairs autophagic substrate *** suggests that glial Atg9 participates in the early steps of autophagy,and hence the control of autophagic ***,loss of glial atg9 induces parkinsonian symptoms in Drosophila including progressive loss of dopaminergic neurons,locomotion deficits,and glial *** findings identify a functional role of Atg9 in glial autophagy and establish a potential link between glial autophagy and Parkinson’s *** results may provide new insights on the underlying mechanism of Parkinson’s disease.

关键词： Atg9 autophagy glia Parkinson’s disease

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