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‘Relationships between relationships’ in forest stands: intercepts and exponents analyses

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Journal of Forestry Research 2018年第3期29卷 575-582页

作者： vladimir l.gavrikov Institute for Ecology and Geography Chair of Ecology and Environmental Studies Siberian Federal University

Relationships between diameter at breast height(dbh) versus stand density, and tree height versus dbh(height curve) were explored with the aim to find if there were functional links between correspondent parameters of the relationships, exponents and intercepts of their power functions. A geometric model of a forest stand using a conic approximation suggested that there should be interrelations between correspondent exponents and intercepts of the relationships. It is equivalent to a type of ‘relationship between relationships’ that might exist in a forest stand undergoing self-thinning, and means that parameters of one relationship may be predicted from parameters of another. The predictions of the model were tested with data on forest stand structure from published databases that involved a number of trees species and site quality levels. It was found that the correspondent exponents and intercepts may be directly recalculated from one another for the simplest case when the total stem surface area was independent of stand density. For cases where total stem surface area changes with the drop of density, it is possible to develop a generalization of the model in which the interrelationships between correspondent parameters(exponents and intercepts) may be still established.

关键词： Total stem surface area Self-thinning Conic approximation Power function Exponent Intercept Scots pine

How much carbon can the Siberian boreal taiga store： a case study of partitioning among the above-ground and soil pools

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Journal of Forestry Research 2016年第4期27卷 907-912页

作者： vladimir l.gavrikov Ruslan A.Sharafutdinov Anastasyia A.Knorre Nina V.Pakharkova Olga M.Shabalina Irina N.Bezkorovaynaya Irina V.Borisova Marina G.Erunova Rem G.Khlebopros Chair of Ecology and Environmental Studies Institute for Economics Management and Environmental StudiesSiberian Federal University Bldg 79 Svobodnyi St.Krasnoyarsk 660041 Russian Federation State Nature Reserve 'Stolby' Bldg 26a Kariemaya St.Krasnoyarsk 660006 Russian Federation Krasnoyarsk State Agricultural University 90 Mira Av.Krasnoyarsk 660049 Russian Federation International Center for Research of Extreme States of Organism at the Presidium of the Krasnoyarsk Research Center Siberian Branch Russian Academy of SciencesAkademgorodok 50 Krasnoyarsk 660036Russian Federation

In the context of global carbon cycle management, accurate knowledge of carbon content in forests is a relevant issue in contemporary forest ecology. We measured the above-ground and soil carbon pools in the darkconiferous boreal taiga. We compared measured carbon pools to those calculated from the forest inventory records containing volume stock and species composition data. The inventory data heavily underestimated the pools in the study area（Stolby State Nature Reserve, central Krasnoyarsk Territory, Russian Federation）. The carbon pool estimated from the forest inventory data varied from 25（t ha-1）（low-density stands） to 73（t ha-1）（highly stocked stands）. Our estimates ranged from 59（t ha-1）（lowdensity stands） to 147（t ha-1）（highly stocked stands）. Our values included living trees, standing deadwood, living cover, brushwood and litter. We found that the proportion of biomass carbon（living trees）： soil carbon varied from99：1 to 8：2 for fully stocked and low-density forest stands,respectively. This contradicts the common understanding that the biomass in the boreal forests represents only16–20 % of the total carbon pool, with the balance being the soil carbon pool.

关键词： stands forests boreal biomass litter varied inventory partitioning store ecology

Ferroelectricity Induced by Oxygen Vacancies in Rhombohedral ZrO_(2) Thin Films

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Energy & Environmental Materials 2024年第1期7卷 229-237页

作者： Veniero lenzi José P.B.Silva Břetislav Šmíd vladimir Matoín Cosmin M.Istrate Corneliu Ghica Judith l.MacManus-Driscoll luís Marques Physics Center of Minho and Porto Universities(CF-UM-UP) University of MinhoCampus de Gualtar 4710-057Braga Portugal laboratory of Physics for Materials and Emergent Technologies LapMETUniversity of Minho4710-057Braga Portugal Department of Surface and Plasma Science Faculty of Mathematics and PhysicsCharles UniversityV Holešovičkách 218000Prague 8 Czech Republic National Institute of Materials Physics 105 bis Atomistilor 077125Magurele Romania Department of Materials Science and Metallurgy 27 Charles Babbage Rd.Cambridge CB3 OFSUK

Rhombohedral phase Hf_(x)Zr_(1.x)O_(2)(HZO,x from 0 to 1)films are promising for achieving robust ferroelectric polarization without the need for an initial wake-up pre-cycling,as is normally the case for the more commonly studied orthorhombic ***,a large spontaneous polarization observed in rhombohedral films is not fully understood,and there are also large discrepancies between experimental and theoretical *** this work,in rhombohedral ZrO_(2)thin films,we show that oxygen vacancies are not only a key factor for stabilizing the phase,but they are also a source of ferroelectric polarization in the *** is shown experimentally through the investigation of the structural properties,chemical composition and the ferroelectric properties of the films before and after an annealing at moderate temperature(400℃)in an oxygen environment to reduce the V_(o)concentration *** experimental work is supported by density functional theory(DFT)calculations which show that the rhombohedral phase is the most stable one in highly oxygen defective ZrO_(2)*** DFT calculations also show that V_(o)contribute to the ferroelectric *** findings reveal the importance of V_(o)for stabilizing rhombohedral ZrO_(2)thin films with superior ferroelectric properties.

关键词： charged defects ferroelectric polarization rhombohedral phase stability zirconia

ChatGPT: Application in Chemistry Education and Challenges

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Journal of Computer and Communications 2024年第3期12卷 196-206页

作者： vladimir l. Kodkin Ekaterina V. Artem’eva Power Engineering Faculty South Ural State University Chelyabinsk Russia Department of Chemistry Institute of Natural Sciences South Ural State University Chelyabinsk Russia

The paper discusses the advancements and applications of neural networks, specifically ChatGPT, in various fields, including chemistry education and research. It examines the benefits of AI and ChatGPT, such as their ability to process and analyze large amounts of data, create personalized training systems, and offer problem-solving recommendations. The paper delves into practical applications, showcasing how ChatGPT can be utilised to augment chemistry learning. It provides examples of using ChatGPT for creating tests, generating multiple-choice questions, and studying chemistry in general. Concerns are voiced about the ethical and societal impact of AI development. In conclusion, it explores the exciting potential of AI to tackle challenges that may exceed human capabilities alone, paving the way for further exploration and collaboration between humans and intelligent machines.

关键词： ChatGPT 3.5 Artificial Intelligence AI for Education Computer-Based learning

Removal of endocrine disrupting chemicals from water through urethane functionalization of microfiltration membranes via electron beam irradiation

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Frontiers of Environmental Science & Engineering 2024年第4期18卷 61-74页

作者： Zahra Niavarani Daniel Breite Muhammad Yasir vladimir Sedlarik Andrea Prager Nadja Schönherr Bernd Abel Roger Gläser Agnes Schulze leibniz Institute of Surface Engineering eV.(IOM) Permoserstrasse 1504318 LeipzigGermany Centre of Polymer Systems University InstituteTomas Bata University in ZlinTrida Tomase Bati 567876001 ZlinCzech Republic Institute of Chemical Technology Leipzig UniversityLinnestrasse 304103 LeipzigGermany

Polyethersulphone(PES)membranes modified with urethane functional groups were prepared through an interfacial reaction using electron beam *** removal of eight endocrine disrupting chemicals(EDCs)was studied using both pristine and functionalized PES *** prepared membranes underwent characterization using several techniques,including attenuated total reflectance-Fourier transform infrared(ATR-FTIR)spectroscopy,scanning electron microscopy,contact angle analysis,and measurements of pure water ***,dynamic adsorption experiments were conducted to evaluate the adsorption mechanism of the prepared membrane toward the eight *** urethane functionalized membranes were hydrophilic(52°contact angle)and maintained a high permeate flux(26000 l/h m^(2) bar)throughout the filtration *** adsorption results demonstrated that the introduction of urethane functional groups on the membranes significantly enhanced the removal efficiency of 17β-estradiol,estriol,bisphenol A,estrone,ethinylestradiol,and *** adsorption loading of 17β-estradiol on the functionalized PES membrane was 6.7±0.7 mg/m^(2),exhibiting a 5-fold increase compared to the unmodified PES *** membranes were successfully regenerated and reused for three adsorption cycles without experiencing any loss of adsorption capacity.

关键词： Surface functionalization Electron beam irradiation Microfiltration Endocrine disrupting chemicals

Contribution to the Characterization of laterites Developed on Granitic Rock in Mbanga (littoral-Cameroon): Significance in the Sustainable Pavements Design

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Journal of Geoscience and Environment Protection 2024年第3期12卷 181-191页

作者： Willy Chance Guimezap Kenou vladimir Willianov Keubou Tatapzia Bertile Ilalie Manefouet Institut Universitaire de la cô te P&#244le de Recherche de l&#8217Inovation et de l&#8217Entreprenariat (PRIE) Douala Cameroun Faculty of Sciences University of Dschang Dschang Cameroon

The materials studied were lateritic soils from Souza-Mbanga-Cameroon, with a view to their better use in road geotechnics. In order to achieve the set objective, the work was carried out in two phases, firstly in the field, to provide a morpho-structural description of the soil profiles, followed by a laboratory phase to analyse the samples collected in the field. The results of the physical characterisation of the soil samples show that, for average values, the water content is 9.87%, the percentage of fines 48%, the plasticity index 21.6%, the liquidity limit 50.91%, and the consistency index 1.97. These soils are classified as silty sands in the lCPC classification and as fine soils in the GTR classification. The average value of the maximum dry density is 1.81 g/cm3 and that of the water content at the modified Proctor optimum is 16.24%. The CBR index is between 1.8% and 17.8%, showing that these soils belong to classes S1, S2, S3, S4 and S5. Souza-Mbanga lateritic soils can be used in their natural state as subgrades.

关键词： Soils Souza-Mbanga Characterisation CBR

Elaboration of a conceptual solution for the development of the Arctic shelf from seasonally flooded coastal areas

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International Journal of Mining Science and Technology 2022年第1期32卷 113-119页

作者： vladimir S.litvinenko Mikhail V.Dvoynikov vladimir l.Trushko Saint-Petersburg Mining University Saint-Petersburg 199106Russia

Currently,construction of facilities in the Arctic is carried out on sand islands,but there are limitations for remote coastal *** restrictions are associated with the lack of quarries with construction sand in the immediate vicinity of the work site,as well as the risk of seasonal flooding of the *** article includes conceptual solutions for construction of modular piling in Arctic nearshore conditions,upon which drilling rigs and auxiliary equipment can be placed for the purpose of subsequent wildcatting,development and exploratory extended reach drilling wells(with measured depth about 15000 m).During the construction of the modular piling foundations,a mathematical simulation of the thermodynamic condition of the frozen ground was conducted,and the bearing capacity of the foundations was *** proposed solutions will solve these problems by constructing modular pile foundations and placing the necessary infrastructure on them,taking into account the distribution of loads during operation in seasonally flooded areas.

关键词： Drilling&drillholes Stress analysis Offshore engineering Infrastructure planning Geotechnical engineering Extended reach drilling

Penile prosthesis implantation and tunica albuginea incision without grafting in the treatment of Peyronie＇s disease with erectile dysfunction

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Asian Journal of Andrology 2013年第3期15卷 391-394页

作者： Miroslav l Djordjevic vladimir Kojovic School of Medicine University of Belgrade Belgrade 11000 Serbia

We evaluated penile prosthesis implantation with tunica albuginea-relaxing incisions without grafting in the treatment of Peyronie＇s disease associated with erectile dysfunction. Between April 2005 and June 2011, 62 patients underwent surgery due to severe Peyronie＇s disease associated with erectile dysfunction. Malleable and inflatable penile prostheses were inserted in 49 and 13 cases, respectively. Penile prostheses were inserted into the corpora cavernosa using the standard ventral approach. After lifting the neurovascular bundle, the tunica albuginea was incised and opened at the plaque region to correct the deformities and to lengthen the penis. Subsequently, the wide neurovascular bundle was replaced, and all incisions of the tunica albuginea were covered to prevent corporal grafting. In the median follow-up of 35 months （range 14-82 months）, the penis was completely straightened in 59 （95%） patients. Numbness of the glans, which the patients found initially upsetting, decreased or disappeared spontaneously 3-6 months later. Penile prosthesis implantation with tunica albuginea incisions is a viable alternative in the treatment of Peyronie＇s disease because the extensive dissection of the neurovascular bundle allows a good approach to the plaque and provides excellent covering of the incised tunica albuginea without additional grafting.

关键词： erectile dysfunction neurovascular bundle penile prosthesis Peyronie's disease tunica albuginea

Humanization for neurological disease modeling:A roadmap to increase the potential of Drosophila model systems

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Animal Models and Experimental Medicine 2023年第3期6卷 230-236页

作者： vladimir l.Katanaev Department of Cell Physiology and Metabolism Faculty of MedicineUniversity of GenevaGenevaSwitzerland HumanaFly Facility Faculty of MedicineUniversity of GenevaGenevaSwitzerland

Neuroscience and neurology research is dominated by experimentation with *** 75%of neurology disease-associated genes have orthologs in Drosophila mel-anogaster,the fruit fly amenable to complex neurological and behavioral ***,non-vertebrate models including Drosophila have so far been unable to significantly replace mice and rats in this field of *** reason for this situ-ation is the predominance of gene overexpression(and gene loss-of-function)meth-odologies used when establishing a Drosophila model of a given neurological disease,a strategy that does not recapitulate accurately enough the genetic disease condi-tions.I argue here the need for a systematic humanization approach,whereby the Drosophila orthologs of human disease genes are replaced with the human *** approach will identify the list of diseases and the underlying genes that can be adequately modeled in the fruit fly.I discuss the neurological disease genes to which this systematic humanization approach should be applied and provide an example of such an application,and consider its importance for subsequent disease modeling and drug discovery in Drosophila.I argue that this paradigm will not only advance our un-derstanding of the molecular etiology of a number of neurological disorders,but will also gradually enable researchers to reduce experimentation using rodent models of multiple neurological diseases and eventually replace these models.

关键词： disease modeling Drosophila humanization neurological diseases