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A theory to link relationships of stand volume,density,mean diameter and height in forestry data

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Journal of Forestry Research 2021年第1期32卷 15-20页

作者： vladimir L.Gavrikov Chair of Ecology and Environmental Studies Institute Ecology and GeographySiberian Federal University79 pr.SvobodnyiKrasnoyarskRussian Federation 660041

in this study,a geometric model of a growing forest stand has been *** basic relationships considered link stand volume and stand density,diameter at breast height(DBH),mean DBH and mean *** model provides simple formulas connecting the exponents of all the *** of the formulas to real forestry data provided a high level of predictions of an exponent from two others measured through regressions from empirical *** Pinus sylvestris *** were of a static nature,a collection of individual stands,while the Pseudotsuga menziesii(Mirb.)Franco data were dynamic,representing forest stand development over *** ability of the model to predict exponents in the empirical data implies,on the one hand,a substantial level of similarity between the model and the forestry ***,on the other hand,the model gives an example in which parameters of one relationship may be linked to parameters of *** this kind of‘relationship between relationships’may be observed in forest stands undergoing active growth and competition-induced self-thinning.

关键词： Relationship between relationships Selfthinning Forestry data Allometry Scots pine Douglasfir

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冰岛东部最美小镇白日梦想家们的隐世仙境

环球人文地理 2024年第13期 144-153页

作者：邓文倩 vladimir marieagns Nataliya Fotokon Sen isabel Baldovi Marc Jedamus Kristina Ryan Unsplash 摄图网

冰岛东部峡湾，有一个小镇被群山、瀑布环绕，远离城市喧嚣，宛如被时间遗忘的世外桃源。在电影《白日梦想家》中，男主角沃尔特为了找到杂志新刊的底片，踏上了一段奇幻冒险旅程。他在影片里看似穿越了格陵兰岛、冰岛、尼泊尔、喜马拉...

冰岛东部峡湾，有一个小镇被群山、瀑布环绕，远离城市喧嚣，宛如被时间遗忘的世外桃源。在电影《白日梦想家》中，男主角沃尔特为了找到杂志新刊的底片，踏上了一段奇幻冒险旅程。他在影片里看似穿越了格陵兰岛、冰岛、尼泊尔、喜马拉雅山脉……但实际上整部电影的取景地全都在冰岛。影片最令人印象深刻的部分，大概是沃尔特用公仔和小孩子交换滑板后，在一条盘山公路上急速滑行。公路的尽头就是被LonelyPlanet评为“冰岛东部最美小镇”的塞济斯菲厄泽。

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impact of normal stress-induced closure on laboratory-scale solute transport in a natural rock fracture

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第4期12卷 732-741页

作者： Liangchao Zou vladimir Cvetkovic Division of Resources Energy and InfrastructureDepartment of Sustainable DevelopmentEnvironmental Science and EngineeringRoyal Institute of TechnologyStockholm10044Sweden Department of Physical Geography Stockholm UniversityStockholm10691Sweden

The impact of normal stress-induced closure on fluid flow and solute transport in a single rock fracture is demonstrated in this *** fracture is created from a measured surface of a granite rock *** Bandis model is used to calculate the fracture closure due to normal stress,and the fluid flow is simulated by solving the Reynold *** Lagrangian particle tracking method is applied to modeling the advective transport in the *** results show that the normal stress significantly affects fluid flow and solute transport in rock *** causes fracture closure and creates asperity contact areas,which significantly reduces the effective hydraulic aperture and enhances flow ***,the reduced aperture and enhanced channeling affect travel time *** particular,the enhanced channeling results in enhanced first arriving and tailing behaviors for solute *** fracture normal stiffness correlates linearly with the 5th and 95th percentiles of the normalized travel *** finding from this study may help to better understand the stress-dependent solute transport processes in natural rock fractures.

关键词： Normal stress Fluid flow Solute transport Stiffness Particle tracking

Sedimentation History of Neogene Lacustrine Sediments of Sueoka Bela Stena Based on Geochemical Parameters(Valjevo-Mionica Basin,Serbia)

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Acta Geologica Sinica(English Edition) 2008年第6期82卷 1201-1212页

作者： Aleksandra AJNOVi vladimir SiMi Branimir JOVANiEVi Olga CVETKOVi Radovan DiMiTRiJEVi Nenad GRUBiN Center of Chemistry IChTM11000 BelgradeSerbia Faculty of Mining and Geology University of Belgrade11000 BelgradeSerbia Faculty of Chemistry University of Belgrade11000 BelgradeSerbia Rio Tinto Exploration Bulevar A VNOJ-a 7111000 BelgradeSerbia

Sediments of the western part of the Valjevo-Mionica basin （Serbia） were examined both geochemically and mineralogically to explain, on the basis of their sedimentologicai characteristics, the causes of changes in their qualitative and quantitative composition. A total of 62 samples obtained from the drillhole at depths up to 400 m was investigated. Using correlation of the obtained data, six geochemical zones were defined, two of which being specially distinguished by their mineralogical, geochemical and sedimentological characteristics. The first one, upper zone A, consists of banded marlstones interbedded with clay and oil shales and is characterized by presence of analcite and searlesite. These minerals and very high contents of Na20 indicate sedimentation in alkaline conditions with increased salinity in arid climate. That provided pronounced water stratification, as well as higher bioproductivity in the basin and sedimentary organic matter preservation. Therefore, the zone A sediments are characterized by high organic matter contents of the type which provides good potential for production of liquid hydrocarbons. Another specific zone, zone F, contains sediments with very high MgO, K2O and Li concentrations. Their geochemical correlation, as well as almost complete absence of illite in this zone, indicates the presence of interstratified clay mineral type illite-saponite （lithium-bearing Mg-smectite）.

关键词： lacustrine sediments geochemistry searlesite statistical analysis

用于创建数据库和分析冬季运动项目运动员训练信息的技术——以北欧两项为例

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北京体育大学学报 2024年第2期47卷 149-153页

作者：弗拉基米尔·泽布泽耶夫崔明坤(译) 柴可夫斯基国立体育学院俄罗斯柴可夫斯基617740 北京体育大学教育学院中国北京100084

现代体育的显著特点是竞争异常激烈。运动员为了取得最高成绩,往往会进行超负荷的训练[1-3]。运动训练的效率主要取决于对运动员状态信息进行收集、系统化和存储的质量。为了达到这些目的,近年来人们开始使用数据库,它可以将信息存储在... 详细信息

现代体育的显著特点是竞争异常激烈。运动员为了取得最高成绩,往往会进行超负荷的训练[1-3]。运动训练的效率主要取决于对运动员状态信息进行收集、系统化和存储的质量。为了达到这些目的,近年来人们开始使用数据库,它可以将信息存储在计算机系统中,而不是零散地存储在纸质或电子媒介中。如此一来,就可以大大提高决策的效率,这在运动员训练和竞技过程中不断产生大量信息流的情况下尤为重要。

关键词：信息存储现代体育计算机系统运动员训练数据库电子媒介信息流冬季运动项目

Real-time decay of fluorinated fullerene molecules on Cu（001） surface controlled by initial coverage

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Nano Research 2018年第4期11卷 2069-2082页

作者： Andrey i. Oreshkin Dmitry A. Muzychenko Sergey i. Oreshkin vladimir A. Yakovlev Palanichamy Murugan S. Selva Chandrasekaran Vijay Kumar Rauf Z. Bakhtizin Department of Physics Lomonosov Moscow State University 119991 Moscow Russia Sternberg Astronomical institute Lomonosov Moscow State University 119234 Moscow Russia institute of Petrochemical Synthesis Russian Academy of Sciences 119991 Moscow Russia CSiR Central Electrochemical Research institute Karaikudi 630003 Tamil Nadu India Dr. Vijay Kumar Foundation 1969 Sector 4 Gurgaon 122001 Haryana India Center for informatics School of Natural Sciences Shiv Nadar University NH91 Tehsil Dadari Gautam Budh Nagar 201314 Uttar Pradesh India Department of Physical Electronics Bashkir State University 450074 Ufa Russia

in this study, the evolution of C60F18 molecules on a Cu（001） surface was studied by means of scanning tunneling microscopy and density functional theory calculations. The results showed that fluorinated fuUerenes （tortoise-shaped polar C60F18） decay on Cu（001） surfaces by a step-by-step detachment of F atoms from the C60 cage. The most favorable adsorption configuration was realized when the F atoms of C60F18 pointed towards the Cu surface and six F atoms were detached from it. The results also showed that a further decay of C60F12 molecules strongly depended on the initial C60F18 coverage. The detached F atoms initially formed a two-dimensional （2D） gas phase which then slowly transformed into F-induced surface structures. The degree of contact between the C60F12 molecules and the Cu（001） surface depended on the density of the 2D gas phase. Hence, the life-time of fluorinated fullerenes was determined by the density of the 2D gas phase, which was affected by the formation of new F-induced structures and the decay of C60F12 molecules.

关键词： fluorinated fullerene (001) Cu surface two-dimensional (2D)molecular island 2D gas phase self-assembling molecules scanning tunneling microscopy (STM) density functional theory(DFT)

On finite 2-groups all of whose subgroups are mutually isomorphic

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Science China Mathematics 2009年第2期52卷 254-260页

作者： EPULiC vladimir Faculty of Electrical Engineering and Computing University of Zagreb

in this paper we investigate the title groups which we call isomaximal. We give the list of all isomaximal 2-groups with abelian maximal subgroups. Further, we prove some properties of isomaximal 2-groups with nonabelian maximal subgroups. After that, we investigate the structure of isomaximal groups of order less than 64. Finally, in Theorem 14. we show that the minimal nonmetacyclic group of order 32 possesses a unique isomaximal extension of order 64.

关键词： p-groups maximal subgroups minimal nonabelian minimal nonmetacyclic 20D15

Predictors of microsurgical varicocelectomy efficacy in male infertility treatment:critical assessment and systematization

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Asian Journal of Andrology 2023年第1期25卷 21-28页

作者： Azizbek B Shomarufov vladimir A Bozhedomov Nikolay i Sorokin igor P Matyukhov Abdukodir A Fozilov Shukhrat A Abbosov Armais A Kamalov Department of Urology and Andrology Faculty of Fundamental MedicineLomonosov Moscow State UniversityMoscow 119991Russia Department of Urology Tashkent Medical AcademyTashkent 100109Uzbekistan Republican Specialized Scientific-Practical Medical Center of Urology Tashkent 100109Uzbekistan

in this review,we tried to systematize all the evidence(from PubMed[MEDLiNE],Scopus,Cochrane Library,EBSCO,Embase,and Google Scholar)from 1993 to 2021 on the predictors of microsurgical varicocelectomy efficacy in male infertility *** the outcomes of varicocele repair,we considered semen improvement and pregnancy and analyzed them *** on the 2011 Oxford CEBM Levels of Evidence,we assigned a score to each trial that studied the role of the *** systematized the studied predictors based on the total points,which were,in turn,calculated based on the number and quality of studies that confirmed or rejected the studied predictor as significant,into three levels of significance:predictors of high,moderate,and low clinical *** total motile sperm count(TMSC)coupled with sperm concentration can be a significant predictor of semen improvement and pregnancy after *** addition,for semen improvement alone,scrotal Doppler ultrasound(DUS)parameters,sperm DNA fragmentation index(DFi),and bilateral varicocelectomy are reliable predictors of microsurgical varicocelectomy efficacy.

关键词： male infertility microsurgical varicocelectomy predictor pregnancy semen varicocele

Postoperative change of anti-Thomsen-Friedenreich and Tn igG level: The follow-up study of gastrointestinal cancer patients

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World Journal of Gastroenterology 2008年第27期14卷 4352-4358页

作者： Eugeniy P Smorodin Oleg A Kurtenkov Boris L Sergeyev Kristel E Kodar Valentin i Chuzmarov vladimir P Afanasyev Department of Oncology & immunology National Institute for Health Development Oncological Centre North-Estonian Regional Hospital

AiM: To study the influence of tumor removal on the serum level of igG antibodies to tumor-associated Thomsen-Friedenreich (TF), Tn carbohydrate epitopes and xenogeneic αGal, and to elucidate on the change of the level during the follow-up as well as its association with the stage and morphology of the tumor and the values of blood parameters in gastrointestinal cancer. METHODS: Sixty patients with gastric cancer and 34 patients with colorectal cancer in stages Ⅰ-Ⅳ without distant metastases were subjected to follow- up. The level of antibodies in serum was determined by the enzyme-linked immunosorbent assay (ELiSA) using synthetic polyacrylamide (PAA) glycoconjugates. Biochemical and haematological analyses were performed using automated equipment. RESULTS: in gastrointestinal cancer, the TF antibody level was found to have elevated significantly after the removal of G3 tumors as compared with the preoperative level (u = 278.5, P ibody level was elevated in the majority of gastric cancer patients (sign test, 20 vs 8, P ively). in gastrointestinal cancer, the elevated postoperative level of TF, Tn and αGal antibodies was noted in most patients with G3 tumors (sign test, 22 vs 5, P ively), but the elevation was not significant in patients with G1 + G2 resected tumors. The postoperative follow-up showed that the percentage of patients with G3 resected tumors of the digestive tract, who had a mean level of anti-TF igG above the cut- off value (1.53), was significantly higher than that of patients with G1 + G2 resected tumors (χ2 = 3.89, all patients; χ2 = 5.34, patients without regional lymph node metastases; P ients with a tumor in stage i, whose mean anti-TF igG level remained above the cut-off value (1.26), was significantly higher than that of patients with the cancer in stages Ⅲ-Ⅳ (χ2 = 4.71, gastric canc

关键词： igG antibodies Thomsen-Friedenreich Tn αGal Gastrointestinal cancer immunosuppression CA 19-9