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A new species of smooth skink (Squamata： Scincidae： Scincella) from Cambodia

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Zoological Research 2018年第3期39卷 220-240页

作者： Thy Neang Somaly Chan nikolay A. Poyarkov, Jr. Wild Earth Allies Sk. Phnom Penh Thmei Kh. Sen Sok Phnom Penh Cambodia Ministry of Environment Sk. Tonle Bassac Kh. Chamkarmorn Phnom Penh Cambodia Department of Vertebrate Zoology Biological Faculty Lomonosov Moscow State University Moscow 119234 Russia Joint Russian-Vietnamese Tropical Research and Technological Centre Nghia Do Cau Giay Hanoi Vietnam

Based on morphological and genetic evidence we evaluated the taxonomic status of a newly discovered forest-dwelling population of skink （genus Scincella） from the Keo Selma Wildlife Sanctuary, Mondulkiri Province, Cambodia. From phylogenetic analysis of a 668-bp fragment of the mtDNA COl and diagnostic morphological characters we allocate the newly discovered population to the Scincella reevesii-S. rufocaudata species complex and describe it as Scincella nigrofasciata sp. nov. The new skink species can be distinguished from all other Southeast Asian congeners by the following combination of morphological characters： snout-vent length （SVL） 40.0-52.6 mm; relative tail length （TaL/SVL ratio） 1.25-1.94; prefrontals in broad contact; infralabials 6; primary temporals 2; relative forelimb length （FIL/SVL ratio） 0.20-0.22; relative hindlimb length （HIL/SVL ratio） 0.30-0.33; relative forearm length （FoL/SVL ratio） 0.14-0.16; adpressed forelimbs and hind limbs either overlapping （0.4-2.2 mm） or separated （1.9-2.3 mm）; midbody scale rows 32-33, paravertebral scales 69-74, vertebral scales 65-69; dorsal scales between dorsolateral stripes 8; comparatively slender fingers and toes, subdigital lamellae under fourth toe 15-17; dark discontinuous regular dorsal stripes 5-7; distinct black dorsolateral stripes, narrowing to lateral sides and extending to 52%-86% of total tail length. We provide additional information on the holotype of Scincella rufocaudata （Darevsky ＆ Nguyen, 1983）, and provide evidence for the species status of Scincella rupicola. Our discovery brings the number of Scincellaspecies in Cambodia to five and emphasizes the incompleteness of knowledge on the herpetofaunal diversity of this country.

关键词： Mondulkiri Keo Seima WildlifeSanctuary Taxonomy mtDNA COl DNA barcoding Phylogenetics

Constructing Collective Signature Schemes Using Problem of Finding Roots Modulo

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Computers, Materials & Continua 2022年第7期72卷 1105-1122页

作者： Tuan Nguyen Kim Duy Ho Ngoc nikolay A.Moldovyan School of Computer Science Duy Tan UniversityDa NangVietnam Department of Information Technology Ha NoiVietnam ITMO University St.PetersburgRussia

Digital signature schemes are often built based on the difficulty of the discrete logarithm problems,of the problem of factor analysis,of the problem of finding the roots modulo of large primes or a combination of the difficult problems mentioned *** this paper,we use the new difficult problem,which is to find the wth root in the finite ground field GF(p)to build representative collective signature schemes,but the chosen modulo p has a special structure distinct p=Nt_(0)t_(1)t_(2)+1,where N is an even number and t_(0),t_(1),t_(2) are prime numbers of equal magnitude,about 80 *** characteristics of the proposed scheme are:i)The private key of each signer consists of 2 components(K_(1),K_(2)),randomly selected,but the public key has only one component(Y)calculated by the formula Y=K_(w)^(1)_(1) K^(w)_(2)^(2);w_(1)=t_(0)t_(1) and w_(2)=t_(0)t_(2);and ii)The generated signature consists of a set of 3 components(e,S_(1),S_(2)).We use the technique of hiding the signer’s public key Y,which is the coefficientλgenerated by the group nanager,in the process of forming the group signature and representative collective signature to enhance the privacy of all members of the signing collective.

关键词： Computing roots finding roots modulo collective signature signing collective signing group

New Representative Collective Signatures Based on the Discrete Logarithm Problem

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Computers, Materials & Continua 2022年第10期73卷 783-799页

The representative collective digital signature scheme allows the creation of a unique collective signature on document M that represents an entire signing community consisting of many individual signers and many different signing groups,each signing group is represented by a group *** document M,a collective signature can be created using the representative digital signature scheme that represents an entire community consisting of individual signers and signing groups,each of which is represented by a group *** characteristic of this type of letter is that it consists of three elements(U,E,S),one of which(U)is used to store the information of all the signers who participated in the formation of the collective signature on document *** storing this information is necessary to identify the signer and resolve disputes later,it greatly increases the size of *** is considered a limitation of the collective signature representing 3 *** this paper,we propose and build a new type of collective signature,a collective signature representing 2 elements(E,S).In this case,the signature has been reduced in size,but it contains all the information needed to identify the signer and resolve disputes if *** construct the approved group signature scheme,which is the basic scheme for the proposed representative collective signature schemes,we use the discrete logarithm problem on the prime finite *** the end of this paper,we present the security analysis of the AGDS scheme and a performance evaluation of the proposed collective signature schemes.

关键词： Elliptic curve signing group individual signer collective signature group signature

New Collective Signatures Based on the Elliptic Curve Discrete Logarithm Problem

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Computers, Materials & Continua 2022年第10期73卷 595-610页

There have been many digital signature schemes were developed based on the discrete logarithm problem on a finite *** this study,we use the elliptic curve discrete logarithm problem to build new collective signature *** cryptosystem on elliptic curve allows to generate digital signatures with the same level of security as other cryptosystems but with smaller *** extend practical applicability and enhance the security level of the group signature protocols,we propose two new types of collective digital signature schemes based on the discrete logarithm problem on the elliptic curve:i)the collective digital signature scheme shared by several signing groups and ii)the collective digital signature scheme shared by several signing groups and several individual *** two new types of collective signatures have combined the advantages of group digital signatures and collective digital *** signatures have a fixed size and do not depend on the number of members participating in the creation of the final collective *** of the advantages of the proposed collective signature protocols is that they can be deployed on top of the available public key infrastructures.

关键词： Elliptic curve signing group individual signer collective signature group signature

pRb-E2F signaling in life of mesenchymal stem cells:Cell cycle,cell fate,and cell differentiation

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Genes & Diseases 2014年第2期1卷 174-187页

作者： Boris Popov nikolay Petrov Institute of Cytology Russian Academy of SciencesSt.Petersburg4Tikhoretsky Av.194064Russia

Mesenchymal stem cells(MSCs)are multipotent cells that can differentiate into various mesodermal lines forming fat,muscle,bone,and other lineages of connective *** possess plasticity and under special metabolic conditions may transform into cells of unusual phenotypes originating from ecto-and *** transplantation,MSCs release the humoral factors promoting regeneration of the damaged *** last five years,the numbers of registered clinical trials of MSCs have increased about 10 *** gives evidence that MSCs present a new promising resource for cell therapy of the most dangerous *** efficacy of the MSCs therapy is limited by low possibilities to regulate their conversion into cells of damaged tissues that is implemented by the pRb-E2F *** widely accepted viewpoint addresses pRb as ubiquitous regulator of cell cycle and tumor ***,current publications suggest that basic function of the pRb-E2F signaling in development is to regulate cell fate and *** facultative and constitutive chromatin modifications,pRb-E2F signaling promotes transient and stable cells quiescence,cell fate choice to differentiate,to senesce,or to *** of pRb is associated with cancer cell *** regulates cell fate by retaining quiescence of one cell population in favor of commitment of another or by suppression of genes of different cell *** is the founder member of the“pocket protein”family possessing functional *** increase in the efficacy of the MSCs based cell therapy will depend on precise understanding of various aspects of the pRb-E2F signaling.

关键词： Cell cycle Cell differentiation Cell fate Mesenchymal stem cells pRb-E2F signaling

Cognitive disorder in brain concussion

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Frontiers in Biology 2014年第4期9卷 332-337页

作者： Vladimir ZAKHAROV Ekaterina DROZDOVA nikolay YAKHNO Neurological Department of First Moscow Medical University LM.Setchenov Moscow 119991 Russia Traumatologic and Neurosurgery Department City Clinical Hospital No. 13 Nizhny Novgorod Russia

This paper presented original study results concerning the prevalence and clinical characteristics of cognitive impairment associated with brain concussion. The cognitive functions of 80 consecutive patients （mean age = 37.40±1l.74years; 50 men and 30 women） admitted to the hospital with brain concussions were evaluated. Their cognitive scores were compared with 40 age- and education-matched healthy volunteers without history of cranial trauma. Cognitive impairment without dementia was found in 93% of the patients. Cognitive impairment in brain concussion was also characterized by prominent cognitive slowness （bradyphrenia）, concentration decrease, free recall insufficiency, and visual-spatial dysfunction. Age and severity of anxiety significantly influence the cognitive performance of patients.

关键词： brain concussion cognitive impairment

Hybrid model for prediction of welding distortions in large structures

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Frontiers of Materials Science 2011年第2期5卷 209-215页

作者： Vesselin MICHAILOV nikolay DOYNOV Christoph STAPELFELD Ralf OSSENBRINK Chair of Joining and Welding Technology Brandenburg Technical University of Cottbus Konrad-Wachsmann-Allee 17 03046 Cottbus Germany

The paper presents a short overview of the contemporary approaches for calculating welding distortions. In order to meet the existing challenges, an advanced hybrid model for prediction of welding distortions in large structures is described. For the purpose of illustrating the capability of this model, a simulation case is put into discussion. The results are validated by comparison with experimental data, as well as with common simulation technique. Analysis of the calculation costs is also presented. The directions for development of calculation technique, based on the presented model, are also suggested.

关键词： hybrid model welding distortion calculation

SnSi nanocrystals of zinc-blende structure in a Si matrix

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Nano Research 2015年第12期8卷 3905-3911页

作者： Alexander Tonkikht Andrey Klavsyuk nikolay Zakharov Alexander Saletsky Peter Werner Max Planck Institute of Microstructure Physics Halle(Saale) 06120 Germany Faculty of Physics Moscow State University Moscow 119991 Russian Federation

A zinc-blende （sphalerite） crystallographic structure of SnSi nanocrystals generated by molecular-beam epitaxy is observed by electron microscopy techniques in a Si matrix. Ab initio density-functional modeling reveals a stabilizing effect of the Si matrix, which results in the lowest formation enthalpy of SnSi nanocrystals having the unexpected zinc-blende structure. Such nanocrystals could be applied in Si photonics to function as non-centrosymmetric media for the nonlinear optical process of second harmonic generation.

关键词： epitaxy density functional theory zinc-blende Si-Sn alloy

Study on Russian Natural Gas Export Strategy

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Study on Russian Natural Gas Export Strategy

作者： nikolay Khovrov 中国石油大学(北京)

学位级别：硕士

Natural gas industry takes one of the biggest role of Russian *** relations between Russia and other countries significantly depend by natural gas supply,where the pricing mechanism takes the key ***,it shows a solid desire to study the Russian natural gas export *** thesis firstly summarized the general theory of the natural gas mechanism and pricing practice forming of Russian and foreign ***,this thesis takes an analysis of Gazprom’s statistics from 1995 to *** on the factors affecting on the price of natural gas,this thesis formulates an econometric model to identify the dependence of Russian gas price on the border of Germany by variables such as the price of oil,the price of gas on NBP and the volume of exported *** on the identified parameters,this thesis determines the dependence of imported gas price to China from Russia from the volume of deliveries,prices of oil and the LNG *** this thesis establishes the optimal price for Russian natural gas to the Chinese *** that investigates political factors that impacts on Russian gas export *** conclusion,this thesis sum up the study,describes the prospects of Russian gas exports to Europe – which is seek to abandon the Ukrainian transit by *** declare the factors that can change the situation in the partnership between Russia and *** pointed that the price of gas has a strong dependence on the price of oil and continues to depend on it.

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