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Post-pancreatitis diabetes mellitus and excess intra-pancreatic fat deposition as harbingers of pancreatic cancer

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World Journal of gastroenterology 2021年第17期27卷 1936-1942页

作者： Maxim S petrov School of Medicine The University of AucklandAuckland 1142New Zealand

Progress in the fight against pancreatic cancer has been hampered by many *** of them is the inability to detect the disease early in overwhelming majority of *** present paper outlines a novel way in which progress could be *** includes a focus on two harbingers—post-pancreatitis diabetes mellitus and excess intra-pancreatic fat deposition—that converge at affecting the tumor macroenvironment and microenvironment specifically in the pancreas,not other *** two entities have the potential to be incorporated into future screening strategies with a view to early detecting of pancreatic cancer.

关键词： Pancreatic cancer Post-pancreatitis diabetes mellitus Intra-pancreatic fat Pancreatitis Early detection Screening

Specificity of electrophysical and gas-sensitive properties of nanocomposite ZnO–TiO_(2) films formed by solid-phase pyrolysis

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ChemPhysMater

ChemPhysMater 2024年第3期3卷 314-319页

作者： victor v.petrov Maria g.volkova Alexsandra P.Ivanishcheva gleb v.Tolstyak Ekaterina M.Bayanb Institute of Nanotechnologies Electronicsand Equipment EngineeringSouthern Federal UniversityTaganrog 347922Russia Faculty of Chemistry Southern Federal UniversityRostov-on-Don 344090Russia

ZnO–TiO_(2) thin films containing 0.5 mol%,1.0 mol%,and 5.0 mol%ZnO were synthesized by oxidative solidphase *** materials contained anatase and rutile phases with particle size of 6–13 nm,as confirmed using X-ray phase analysis and scanning electron *** a certain number of ZnO crystallites appeared in the TiO_(2) film structure in the temperature range of room temperature to 220℃,a two-level response of the film resistance was observed,differing by approximately 10%,as obtained by electrophysical *** two-level response correlates with the formation of two donor energy levels of 0.28 and 0.33 ev in the band structure of the ZnO–TiO_(2) *** donor level with a higher activation energy corresponded to the Ti vacancy(v−Ti),and that with a lower activation energy corresponded to the Zn vacancy(v−Zn).Two levels of gas-sensitive properties were noted for 0.5ZnO–TiO_(2),1ZnO–TiO_(2),and 5ZnO–TiO_(2) under the influence of 50 ppm NO_(2) at 250℃.Such two-level responses can be ascribed to the pinning of the Fermi level on ZnO and TiO_(2) *** mechanism of the beak-shaped and two-level responses of sensors based on composite nanomaterials when exposed to various gases was elucidated.

关键词： Thin film ZnO TiO_(2) Nanocomposites Pyrolysis gas sensors

Dynamic failure of dry and fully saturated limestone samples based on incubation time concept

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Journal of Rock Mechanics and geotechnical Engineering 2017年第1期9卷 125-134页

作者： Yuri v. petrov Ivan v. Smirnov grigory A. volkov Andrei K. Abramian Anatoliy M. Bragov Stanislav N. verichev Saint Petersburg University Universitetskaya nab. 7-9 Saint Petersburg 199034 Russia Institute of Problems of Mechanical Engineering Russian Academy of Sciences Bolshoj pr. 61 V.O. Saint Petersburg 199178 Russia Lobachevsky State University of Nizhni Novgorod Prospekt Gagarina 23 Nizhny Novgorod 603950 Russia Allseas Engineering B.v. Poortweg 12 Delft 2612 PA The Netherlands

This paper outlines the results of experimental study of the dynamic rock failure based on the comparison of dry and saturated limestone samples obtained during the dynamic compression and split tests. The tests were performed using the Kolsky method and its modifications for dynamic splitting. The mechanical data(e.g. strength, time and energy characteristics) of this material at high strain rates are obtained. It is shown that these characteristics are sensitive to the strain rate. A unified interpretation of these rate effects, based on the structuraletemporal approach, is hereby presented. It is demonstrated that the temporal dependence of the dynamic compressive and split tensile strengths of dry and saturated limestone samples can be predicted by the incubation time criterion. Previously discovered possibilities to optimize(minimize) the energy input for the failure process is discussed in connection with industrial rock failure processes. It is shown that the optimal energy input value associated with critical load, which is required to initialize failure in the rock media, strongly depends on the incubation time and the impact duration. The optimal load shapes, which minimize the momentum for a single failure impact, are demonstrated. Through this investigation, a possible approach to reduce the specific energy required for rock cutting by means of high-frequency vibrations is also discussed.

关键词： Dynamic strength Incubation time criterion Split Hopkinson pressure bar(SHPB) test Tensile strength Compressive strength Water-saturated limestone vibration-assisted rock cutting

v2551 Cyg:a pulsating star with enigmatic peculiarities

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Research in Astronomy and Astrophysics 2017年第7期17卷 57-66页

作者： Diana P.Kjurkchieva velimir A.Popov Dragomir v.Marchev Kenneth T.Menzies Nikola I.petrov Department of Physics Shumen University IRIDA Observatory Rozhen NAO Tigh Speuran Observatory Institute of Astronomy and NAO Bulgarian Academy of Sciences

Intensive photometric and spectral observations of the variable star v2551 Cyg are *** light curve shape reveals that the target is a pulsating star, contrary to its previous classification as an eclipsing binary. The period and amplitude of the light curve, the amplitudes of color changes and the radial velocity curve of v2551 Cyg are similar to those of a high-amplitude δ Scuti variable. The target seems to pulsate with the fundamental mode. However, v2551 Cyg exhibits several important peculiarities：（i） the decreasing branch of its light curve is steeper than the increasing one;（ii） the radial velocity curve has a flat section in the phase range 0.7-1.2 and short increase of the negative radial velocity at phase 0.7;（iii） the rotational velocity is quite big for a HADS star;（iv） the Fourier coefficients of v2551 Cyg are quite different from those of HADS stars. The target classification is difficult due to these peculiarities.

关键词： stars variables delta Scuti - stars variables RR Lyrae - stars individual (v2551 Cyg)

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中国北方盆地大规模铀成矿作用:地层篇

地质学报 2024年第7期98卷 1953-1976页

作者：程银行金若时 Michel CUNEY v.A.petrov 苗培森中国地质调查局天津地质调查中心(华北地质科技创新中心) 天津300170 中国地质调查局铀矿地质重点实验室天津300170 法国洛林大学资源学院法国NancyF54500 俄罗斯科学院矿床地质、岩石学、矿物学和地球化学研究所俄罗斯Moscow119017

“红黑”耦合沉积建造是中国北方中—新生代盆地(简称北方盆地)砂岩型铀矿的重要控矿要素之一,在勘查实践中得到了广泛证实和应用,指导发现找矿靶区和矿产地300余处,在成矿理论方面取得重要进展。本文系统总结了北方产铀盆地的60万余米... 详细信息

“红黑”耦合沉积建造是中国北方中—新生代盆地(简称北方盆地)砂岩型铀矿的重要控矿要素之一,在勘查实践中得到了广泛证实和应用,指导发现找矿靶区和矿产地300余处,在成矿理论方面取得重要进展。本文系统总结了北方产铀盆地的60万余米铀矿岩芯钻探成果,通过典型矿床赋矿层沉积学、地球化学等对比研究,系统分析了北方盆地侏罗系、白垩系、新近系等赋矿层形成的沉积环境、物质组成等,进一步明确了制约成矿流体运移、铀矿物沉淀的赋矿层条件。结果显示:①北方盆地自侏罗纪以来,发育了Ⅰ中侏罗世—晚侏罗世早期(Bathonian-Oxfordian)、Ⅱ早白垩世早期(valanginian)、Ⅲ早白垩世晚期(Aptian)、Ⅳ晚白垩世早期(Cenomanian)、Ⅴ晚白垩世晚期—早古近纪(Campanian-Thanetian)、Ⅵ早新近纪(Aquitanian-Burdigalian)和Ⅶ晚新近纪(ZancleanPiacenzian)7期红层,与下伏富还原性组分的黑色层构成了典型的对偶沉积建造,为北方盆地大规模成矿奠定了赋矿层基础。②地球化学指标显示:红层中Fe^(2+)/Fe^(3+)比值介于0.29~1.47(n=78),黑层Fe^(2+)/Fe^(3+)比值介于0.57~53.96(n=223),赋矿层Fe^(2+)/Fe^(3+)比值介于1.00~26.45(n=52)。赋矿层、黑层Fe^(2+)/Fe^(3+)比值一般大于1,以发育黄铁矿、炭屑、油斑为特征,为相对较还原的环境。红层Fe^(2+)/Fe^(3+)比值一般小于1,以发育钙质结核为特征,为相对较强氧化的环境。③总有机碳含量显示红层为0~0.16%(n=107),含矿层为0.01%~2.65%(n=137),黑层为0.01%~2.66%(n=339),含矿层总有机碳含量略低于黑层,与铀矿的富集沉淀有密切关系。④砂岩型铀矿体呈“板状”或“楔状”产出于黑层顶部的灰色、灰绿色砂岩和细砂岩,甚至泥岩,红层为含氧含铀流体的运移通道,黑层为含氧含铀流体的富集沉淀的化学屏障。因此,北方盆地红层和黑层对偶沉积、旋回充填是大规模铀成矿必要的地层条件,这些认识打破常规思维,“红黑”旋回叠加导致了北方盆地多层成矿的现象,矿体一般呈板状就位于红层和黑层的过渡带,这对深入理解砂岩型铀矿成矿环境、成矿规律及成矿机理等工作和勘查工作部署具有重要实践意义。

关键词：北方中—新生代盆地砂岩型铀矿大规模成矿沉积环境赋矿层

Design of broadband terahertz vector and vortex beams: I. Review of materials and components

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Light(Advanced Manufacturing) 2022年第4期3卷 126-144页

作者： Nikolay v.petrov Bogdan Sokolenko Maksim S.Kulya Andrei gorodetsky Aleksey v.Chernykh Digital and Display Holography Laboratory ITMO UniversitySt.Petersburg 197101Russia v.I.vernadsky Crimean Federal University Simferopol 295007Russia School of Physics and Astronomy University of BirminghamBirmingham B152TTUK

In this paper,we review the existing approaches for vortex and vector beam shaping and generation in the terahertz frequency *** particular focus of this review is on the possibility of homogeneous topological charge formation in the ultra-wide spectral interval inherent to ultrashort terahertz *** review the available materials and components,analyse proposed and potentially possible solutions for broadband terahertz vortex and vector beam shaping,compare all developed approaches,and put forward a unified concept for constructing passive shapers of such beams from the existing component base.

关键词： Terahertz radiation vortex beams vector beams Achromatic wave plates Broadband terahertz radiation Digital holography Terahertz holography Total internal reflection Metasurface THz liquid crystals geometric phase

Design of broadband terahertz vector and vortex beams: II. Holographic assessment

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Light(Advanced Manufacturing) 2022年第4期3卷 14-26页

In this paper,we demonstrate the capabilities of the terahertz pulse time-domain holography in visualisation,simulation,and assessment of broadband THz vortex beam formation dynamics upon its shaping by elements of beam converter,and further propagation and *** adding Jones matrix formalism to describe broadband optical elements,we highlight the differences in the spatio-spectral and spatio-temporal structure of the formed vortex and vector beams dependence on the modulator used and visualise their modal *** influence of diffraction field structure from each element in the broadband vortex modulator is revealed in numerical simulation and the formed beams are analysed against the simplified Laguerre-gaussian beam model.

关键词： Terahertz radiation vortex beams vector beams Achromatic wave plates Broadband terahertz radiation Digital holography Terahertz holography

Parallelization of an Implicit Algorithm for Multi-Dimensional Particle-in-Cell Simulations

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Communications in Computational Physics 2014年第8期16卷 599-611页

作者： george M.petrov Jack Davis Naval Research Laboratory Plasma Physics Division4555 Overlook Ave.SWWashingtonDC 20375USA.

The implicit 2D3v particle-in-cell(PIC)code developed to study the interaction of ultrashort pulse lasers with matter[*** and ***,Computer ***.179,868(2008);*** 18,073102(2011)]has been parallelized using MPI(Message Passing Interface).The parallelization strategy is optimized for a small number of computer cores,up to about *** on the algorithm implementation are given with emphasis on code optimization by overlapping computations with *** evaluation for 1D domain decomposition has been made on a small Linux cluster with 64 computer cores for two typical regimes of PIC operation:”particle dominated”,for which the bulk of the computation time is spent on pushing particles,and”field dominated”,for which computing the fields is *** a small number of computer cores,less than 32,the MPI implementation offers a significant numerical *** the”particle dominated”regime it is close to the maximum theoretical one,while in the”field dominated”regime it is about 75-80%of the maximum *** a number of cores exceeding 32,performance degradation takes place as a result of the adopted 1D domain *** code parallelization will allow future implementation of atomic physics and extension to three dimensions.

关键词： Particle-in-cell Maxwell equations MPI lasertarget interaction.

Diclofenac sodium aqueous systems at low concentrations: Interconnection between physicochemical properties and action on hydrobionts

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Journal of Environmental Sciences 2020年第2期32卷 177-186页

作者： Irina S.Ryzhkina Yuliya v.Kiseleva Lyaisan I.Murtazina Tatyana v.Kuznetsova Erik R.Zainulgabidinov Igor v.Knyazev Andrew M.petrov Sergey E.Kondakov Alexander I.Konovalov Arbuzov Institute of Organic and Physical Chemistry FRC Kazan Scientific CenterRussian Academy of Sciences8 Arbuzov str.Kazan 420088Russia Institute for Problems of Ecology and Mineral Wealth Use of Tatarstan Academy of Sciences 28 Daurskaya Str.Kazan 420087Russia Lomonosov Moscow State University Chemistry Dept.1/3 Lenin HillsMoscow 119899Russia

Diclofenac sodium(DS) is a widely used nonsteroidal anti-inflammatory drug(NSAIDs).NSAIDs are poorly removed during standard wastewater *** consequences of the presence of NSAIDs in rivers and lakes at 10-11–10-8 mol/L are not yet established;therefore, ecotoxicologists have focused their efforts on studying the effect of lowconcentration NSAIDs on fish and hydrobionts, and also on predicting the potential risks to *** provides some information about the bioeffects of some NSAID solutions in low concentrations but there is no physicochemical explanation for these *** the physicochemical patterns of DS solutions in the low range of concentrations and establishing an interconnection between the solutions’ physicochemical properties and bioeffects can provide a conceptually new and important source of information regarding the unknown effects of *** physicochemical properties and action of DS solutions on Ceriodaphnia affinis cladocerans,Paramecium caudatum infusoria, Chlorella vulgaris unicellular green algae, as well as on the growth of the roots of Triticum vulgare wheat seeds, were studied in the calculated concentration range of 1 × 10-3–1 × 10-18 mol/*** relationship between these phenomena was established using the certified procedures for monitoring the toxicity of natural water and *** was shown for the first time that water solutions of DS are dispersed systems in which the dispersed phase undergoes a rearrangement with dilution, accompanied by changes in its size and properties, which affects the nonmonotonic dependences of the system’s physicochemical properties and could cause nonmonotonic changes in action on hydrobionts in the low concentration range.

关键词： Diclofenac sodium Low concentration Aqueous solutions Physicochemical properties Hydrobionts Toxicity