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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第10期11卷 801-805页

作者： Yuriy G.SHCKORBATOV vladimir n.PASIUGA Elena I.GOnCHARUK Tatiana Ph.PETREnKO Valentin A.GRABInA nicolay n.KOLCHIGIn Dmitry D.IVAnCHEnKO Victor n.BYKOV Oleksandr M.DUMIn Kharkiv national University Institute for Problems of Cryobiology and Cryomedicine of the national Academy of Sciences of Ukraine

To investigate the influence of microwave radiation on the human fibroblast nuclei,the effects of three variants of electromagnetic wave polarization,linear and left-handed and right-handed elliptically polarized,were *** conditions were:frequency(f) 36.65 GHz,power density(P) at the surface of exposed object 1,10,30,and 100 μW/cm2,exposure time 10 *** fibroblasts growing in a monolayer on a cover slide were exposed to microwave electromagnetic *** layer of medium that covered cells during microwave exposure was about 1 mm *** were stained immediately after irradiation by 2%(w/v) orcein solution in 45%(w/v) acetic *** were made at room temperature(25 °C),and control cell samples were processed in the same *** assessed heterochromatin granule quantity(HGQ) at 600× *** irradiation at the intensity of 1 μW/cm2 produced no effect,and irradiation at the intensities of 10 and 100 μW/cm2 induced an increase in *** intense irradiation induced more chromatin *** right-handed elliptically polarized radiation revealed more biological activity than the left-handed polarized one.

关键词： Human cells Chromatin Heterochromatin Electromagnetic field Elliptical polarization

Karyotypes of parasitic Hymenoptera： Diversity, evolution and taxonomic significance

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Insect Science 2006年第4期13卷 237-241页

作者： vladimir E.GOKHMAn Botanical Garden Moscow State University Moscow Russia

Haploid chromosome numbers （n） of parasitic Hymenoptera （= traditional Parasitica ＋ Chrysidoidea） vary from 2 to 23. However, this range can be subdivided into three intervals with n = 14-23 （less derived parasitic wasps, e.g., some Ichneumonidae and Braconidae as well as Gasteruptiidae）, 8-13 （many other parasitic Hymenoptera） and 2-7 （Dryinidae, the majority of Chalcidoidea and some advanced Braconidae, e.g. Aphidiinae）. The symmetric karyotype with a relatively high chromosome number （n -- 14-17） and the prevalence of biarmed chromosomes must be considered as a groundplan feature of parasitic Hymenoptera. Independent reductions of chromosome numbers （n ≤ 10-11） occurred in some groups of the superfamily Ichneumonoidea as well as in the common ancestor of the Proctotrupoidea sensu lato, Ceraphronoidea, Cynipoidea and Chalcidoidea. Further mul- tiple decreases in chromosome numbers （n ≤ 4-6） took place in some Braconidae, various lineages of the superfamily Chalcidoidea as well as in the family Dryinidae. Two main trends prevailed in the karyotype evolution of parasitic wasps： the reduction of chromosome numbers （mainly due to tandem fusions and less frequently due to centric ones） and karyotypic dissymmetrization （through an increase in size differentiation of chromosomes and/or in the share of acrocentrics in a chromosome set）. Although karyotypic features of parasitic Hymenoptera can be used for solving taxonomic problems at various levels, this method is the most effective at the species level.

关键词： chromosomes Hymenoptera karyotypes parasitic wasps taxonomy

To the new Concept of Green Tribology

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Journal of Materials Science and Chemical Engineering 2017年第1期5卷 175-187页

作者： vladimir A. Levchenko Ilia A. Buyanovskii vladimir n. Matveenko Lomonosov Moscow State University Leninskii Gory Moscow Russia Institute of Engineering Science RAS M. Kharitonievsky Moscow Russia

The aim of the present work is to confirm the fundamental possibility of creating new generation of the nanostructured composite coatings-orientants are studied under conditions of boundary lubrication in inactive oil, as green tribology aspect and to experimentally prove the efficacy of the nanostructured composite coatings-orientants for engineering applications. Tribological properties of nanostructured composite coatings-orientants are studied under conditions of boundary lubrication in inactive oil, as green tribology aspect. The friction tests were carried out by using two test configurations: “ball-on-disc” and “ring-to-ring”. As lubricants some model and commercial oils were used. It is found that the friction coefficient and its temperature dependence differ significantly for nanostructured composite coatings under study. The obtained results were attributed to different orientating effect of these coatings on structural ordering in boundary layers, which structure is considered as a mesophase of liquid crystals. The findings suggest that the nanostructured composite coatings-orientants with orientating effect on boundary layers are advantageous for improving antifriction characteristics and for governing processes of boundary lubrication. The nanostructured composite coatings-orientants can improve lubricating properties of oils (with and without additives) and may be advantageous for engineering practice as they improve antifriction characteristics of rubbing pairs and allow controlling the processes of boundary lubrication. Thus, received nanostructured composite coatings-orientants can be today the best materials of green tribology in engineering.

关键词： Green Tribology DLC Coatings-Orientant nanostructural Coating Boundary Lubricant Layers Structural Order

Gan功率放大器非线性对无线通信系统的影响研究

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GaN功率放大器非线性对无线通信系统的影响研究

Metformin prevents hormonal and metabolic disturbances and 1,2-dimethylhydrazine-induced colon carcinogenesis in non-diabetic rats

2024年全国微波毫米波会议（中国微波年会）

作者：杜宏宇宋章磊万发雨 vladimir Mordachev Eugene Sinkevich Dmitry Viktorovich Kholodnyak 南京信息工程大学圣彼得堡电工大学

本文研究了3.5GHz Ga n功率放大器的非线性特性及其对无线通信系统性能的影响。首先设计了一款S波段Ga n功率放大器,通过实验测试和分析,得到了3.5GHz Ga n功率放大器线性增益45.5d B,饱和功率40.5d Bm,饱和效率26.9%,1d B压缩点34.6d ... 详细信息

本文研究了3.5GHz Ga n功率放大器的非线性特性及其对无线通信系统性能的影响。首先设计了一款S波段Ga n功率放大器,通过实验测试和分析,得到了3.5GHz Ga n功率放大器线性增益45.5d B,饱和功率40.5d Bm,饱和效率26.9%,1d B压缩点34.6d Bm,该输出功率下三阶交调抑制大于24.5d Bc等射频特性。接着在通信系统性能测试中,对功率放大器非线性在QPSK调制方式下对系统误差向量幅度(EVM)和信噪比(SnR)的影响进行了分析。结果表明,在高功率输入条件下,非线性失真显著降低了通信系统的性能。

关键词： Gan功率放大器非线性特性无线通信系统

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Cancer Biology & Medicine 2017年第1期14卷 100-107页

作者： Viktoria V.Bekusova Vasily M.Patsanovskii Alexander D.nozdrachev Alexandr P.Trashkov Margarita R.Artemenko vladimir n.Anisimov Department of Physiology St.Petersburg State UniversitySt.Petersburg 197183Russia I.P.Pavlov Institute of Physiology Russian Academy of Sciences St.Petersburg 199034Russia Deparment of Experimental Pharmacology I.M.Sechenov Institute of Evolutionary Physiology and BiochemistryThe Russian Academy of SciencesSt.Petersburg 194223Russia Department of Carcinogenesis and Oncogerontology N.N.Petrov Research Institute of OncologySt.Petersburg 197758 Russia

Effects of two doses of the anti-diabetic drug, metformin （MF）, on hormonal and metabolic levels of serum of non-diabetic male Wistar rats with 1,2-dimethylhydrazine （DMH）-induced colon tumor adenocarcinomas were studied. Carcinogenesis in the animals was also observed. Rats with DMH-induced colon adenocarcinomas had elevated levels of serum glucose, insulin, insulin- like growth factor-l, total cholesterol, triglycerides, catalase, malonic dialdehyde, glycated hemoglobin, aspartate aminotransferase, and alanine aminotransferase and decreased hemoglobin. Treatment with two doses of MF normalized maiority of these changes in DMH-treated rats, whereas the drug was ineffective in rats without DMH treatment. The only exception was the decreased triglyceride levels in MF-treated rats. A 100 mg/kg dose of MF increased DMH-induced exophytic colon carcinomas and decreased endophytic tumors compared with untreated rats. Moreover, both MF doses increased DMH-induced and highly differentiated tumors and decreased the invasiveness of colon carcinomas compared with rats provided with DMH and water. Therefore, effects of MF on metabolic homeostasis are critical for preventing colon cancer.

关键词： Colon cancer prevention 1,2-dimethylhydrazine mefformin rat

Transient expression of inactive RB in mesenchymal stem cells impairs their adipogenic potential and is associated with hypermethylation of the PPARγ2 promoter

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Genes & Diseases 2022年第1期9卷 165-175页

作者： Mikhail Baryshev nikolai Petrov vladimir Ryabov Boris Popov Institute of Cytology Russian Academy of Sciences St.Petersburg4Tikhoretsky Av.194064St.PetersburgRussia Institute of Microbiology and Virology Riga Stradins UniversityRatsupites 5LV-1067RigaLatvia Developmental Therapeutics Branch National Cancer InstituteNational Institutes of HealthBethesdaMaryland 20892USA

The retinoblastoma gene product(pRb)is a chromatin-associated protein that can either suppress or promote activity of key regulators of tissue-specific *** found that twelve weeks after transfection of the exogenous active(ΔB/X andΔр34)or inactive(ΔS/n)forms of RB into the 10T1/2 mesenchymal stem cells and clonal selection not a single cell line did contain exogenous RB,despite being G-418 ***,the consequences of the transient production of exogenous RB had different effects on the cell ***ΔB/X andΔр34 cells transfected with active form of RB showed elevated levels of inducible adipocyte differentiation(AD).On the contrary,theΔS/n cells transfected with inactive RB mutant were insensitive to induction of AD associated with abolishing of expression of the PPARγ***,the PPARγ2 promoter in undifferentiatedΔS/n cells was hypermethylated,but all except−60 position CpG became mostly demethylated after cells exposure to *** conclude that while transient expression of inactive exogenous RB induces long term epigenetic alterations that prevent adipogenesis,production of active exogenous RBs results in an AD-promoting epigenetic *** results indicate that pRb is involved in the establishment of hereditary epigenetic memory at least by creating a methylation pattern of PPARγ2.

关键词： Adipogenic differentiation DnA methyltransferase 1 Mesenchymal stem cells MSCs RB Retinoblastoma susceptibility gene

The Effect of Micro-Structure on Fatigue Behaviour of Intact Sandstone

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International Journal of Geosciences 2011年第3期2卷 240-247页

作者： Manoj n.Bagde vladimir Petros Central Institute of Mining and Fuel Research Regional CentreMECL ComplexNagpurIndia Faculty of Mining and Geology VSB-TUOstravaCzech Republic

With advent of servo-controlled stiff testing machines, it is now possible to conduct tests on a rock in the laboratory under different variable controlled conditions. In this paper, cyclic fatigue behaviour of intact sandstone obtained from the rock burst prone coal mine in the Czech Republic were presented. Tests were conducted on MTS- 816 rock test system in the laboratory on intact rock samples of L/D ratio 2 under cyclic loading frequency of 0.1, 1, 3, 5, 7 and 10 Hz at amplitude of 0.1 mm under displacement control mode until failure of the samples in uni-axial compression. From, the primary results it was observed that at low loading frequency range of 0.1 to 3 Hz, there was degradation of the rock samples in terms of fatigue strength and modulus. While, at higher frequency rose-up in strength and deformation properties were observed. It was observed that the machine behaviour in terms of amplitude at higher loading frequencies might be affecting the results. It seemed that machine behaviour of servo-hydraulic testing system was also dependent on rock type under investigation.

关键词： Cyclic Loading Fatigue Micro-Structure Machine Behaviour Rock Memory

Identifying sex-specific injury predictors as a key factor in maintaining optimal physical activity levels

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World Journal of Orthopedics 2023年第3期14卷 146-154页

作者： Maria V Sankova vladimir n nikolenko Marine V Oganesyan Andjela D Vovkogon Aida n Gadzhiakhmedova Tatyana S Zharikova Yury O Zharikov Department of Human Anatomy and Histology I.M.Sechenov First Moscow State Medical University(Sechenov University)Moscow 125009Russia Department of normal and Topographic Anatomy Lomonosov Moscow State UniversityMoscow 119991Russia European Osteopathic Clinical Center of the Moscow Branch of the“Medical Academy of Osteopathic Education” Saint Petersburg 199106Russia Institute of Clinical Medicine I.M.Sechenov First Moscow State Medical University(Sechenov University)Moscow 119991Russia

BACKGROUnD Optimal physical activity is known to reduce cardiovascular,respiratory and endocrine system diseases and,as a consequence,improve quality of *** important risk factor for reinjuries during normal exercise is the initial connective tissue *** variety of clinical dysplastic manifestations significantly complicate the timely diagnosis of this *** To establish pathognomonic sex-specific dysplasia phenotypes that indicate a particular sensitivity to physical *** The study involved 117 participants with recurrent musculoskeletal injuries that occurred during normal *** were 67 women(57.26%)and 50 men(42.74%),which made it possible to compare the presence of the identified signs between sexes.A validated questionnaire was used to screen their connective tissue *** Ranking the most commonly revealed dysplasia signs depending on their clinical significance made it possible to establish pathognomonic sex-specific phenotypes that indicated a particular susceptibility to *** programs of optimal physical activity are necessary for men with chest deformities,flat-valgus feet,dolichostenomelia,arachnodactylia,hemorrhoids,abdominal muscle diastasis and recurrent *** women,special sensitivity to physical exertion was associated with a combination of signs such as asthenic body,joint hypermobility,overly soft auricles,thin hyperelastic skin,atrophic striae,telangiectasias and varicose *** particular importance were universal signs such as gothic palate,scoliosis,kyphosis,leg deformities,temporomandibular joint crunching,and moderate to high *** Participants’connective tissue condition should be considered when designing optimal physical activity *** the established sex-specific dysplasia phenotypes will allow timely optimization of training loads,thus reducing the risk of injury.

关键词： Injury risk Physical activity Connective tissue condition Sex-specific dysplasia phenotypes Clinical dysplastic manifestations

Cold Seeps Associated with Structured Benthic Communities: More Accurate Identification and Evaluation Using a new Multibeam Survey Methodology in the Offshore Southern Colombian Caribbean

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International Journal of Geosciences 2016年第5期7卷 761-774页

作者： Adrian Digby vladimir Puentes Jorge León Lionel Fray Associates Katy Texas USA Aquabiosfera & Anadarko PC Inc. Woodlands Texas USA Anadarko Colombia Bogota Colombia

A new methodology was developed to identify cold seeps and structured benthic communities associated, which was applied for the first time in the offshore southern Colombian Caribbean. The integral method consists on a new processing of double-coverage (200%) high-resolution backscatter data combined with bathymetric information;validation was done correlating identified gas plumes, seabed cores and drift camera surveys. Results showed that the elimination of artefacts and the increased signal of the backscatter data allowed accurate plotting of seep boundaries and categorization of seeps into an activity catalogue, with more than 200 seeps identified. Most seeps have chemosynthetic communities associated and data analysis from a previous survey showed two ridges with hard ground as the only possible areas for the development the of deep- water corals. Seep results were compared with designated Areas of Significance for Biodiversity (ASB) identifying seeps both within and outside the ASBs, and showing that the presence of seeps and chemosynthetic communities associated were driven more by geological processes than for big-scale seabed morphology, since they were found in both plains and ridges. This methodology allows an accurate seabed map of structured benthic communities, which may work as a precise geo-hazard map to ensure the oil & gas industry can avoid these areas of shallow gas for further developments, and as a map of deep-water structured benthic communities with environmental significance.

关键词： Backscatter Cold Seeps Chemosynthetic Communities Southern Colombian Caribbean

Electrical triggering of earthquakes:results of laboratory experiments at spring-block models

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Earthquake Science 2017年第4期30卷 167-172页

作者： Victor A.novikov vladimir I.Okunev Vadim n.Klyuchkin Jing Liu Yuri Ya.Ruzhin Xuhui Shen Joint Institute for High Temperatures of Russian Academy of Sciences MoscowRussia Institute of Earthquake Science China Earthquake AdministrationBeijingChina Pushkov Institute of Terrestrial Magnetism and Radio Wave Propagation TroitskMoscow RegionRussia Institute of Crustal Dynamics China Earthquake AdministrationBeijingChina

Recently published results of field and laboratory experiments on the seismic/acoustic response to injection of direct current （DC） pulses into the Earth crust or stressed rock samples raised a question on a possibility of electrical earthquake triggering. A physical mechanism of the considered phenomenon is not clear yet in view of the very low current density （10-7-10-s A/m^2） generated by the pulsed power systems at the epicenter depth （5-10 km） of local earthquakes occurred just after the current injection. The paper describes results of laboratory ＂earthquake＂ triggering by DC pulses under conditions of a spring-block model simulated the seismogenic fault. It is experimentally shown that the electric triggering of the laboratory ＂earthquake＂（sharp slip of a movable block of the spring-block system） is possible only within a range of subcritical state of the system, when the shear stress between the movable and fixed blocks obtains 0.98-0.99 of its critical value. The threshold of electric triggering action is about 20 A/m^2 that is 7-8 orders of magnitude higher than estimated electric current density for Bishkek test site （northern Tien Shan, Kirghizia） where the seismic response to the man-made electric action was observed. In this connection, the electric triggering phenomena may be explained by contraction of electric current in the narrow conductive areas of the faults and the corresponding increase in current density or by involving the secondary triggering mechanisms like electromagnetic stimulation of conductive fluid migration into the fault area resulted in decrease in the fault strength properties.

关键词： Earthquake simulation Spring-block model Electric pulse Triggering threshold