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Small Ubiquitin-Like Modifier Conjugating Enzyme with Active Site Mutation Acts as Dominant Negative Inhibitor of SUMO Conjugation in Arabidopsis

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Journal of Integrative Plant Biology 2013年第1期55卷 75-82页

作者： konstantin Tomanov Christian Hardtke Ruchika Budhiraja Rebecca Hermkes George Coupland Andreas Bachmair Department of Biochemistry and Cell Biology Max F. Perutz Laboratories Center for Molecular Biology University of Vienna Department of Plant Molecular Biology University of Lausanne Department of Plant Developmental Biology Max Planck Institute for Plant Breeding Research

Small ubiquitin-like modifier （SUMO） conjugation affects a broad range of processes in plants, including growth, flower initiation, pathogen defense, and responses to abiotic stress. Here, we investigate in vivo and in vitro a SUMO conjugating enzyme with a Cys to Ser change in the active site, and show that it has a dominant negative effect. In planta expression significantly perturbs normal development, leading to growth retardation, early flowering and gene expression changes. We suggest that the mutant protein can serve as a probe to investigate sumoylation, also in plants for which poor genetic infrastructure precludes analysis via loss-of-function mutants.

关键词： Agroinfection conjugating enzyme dominant-negative active site mutation small ubiquitin-like modifier conjugation small ubiquitin-like modifier.

Plasma treatment for enhancement of the sorption capacity of carbon fabric

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Plasma Science and Technology 2021年第12期23卷 150-160页

作者： IIya ZADIRIEV Elena KRALKINA Vladimir SAMOILOV Victoria ELCHANINOVA Valentina GORINA Ilya IVANENKO konstantin VAVILIN Alexander NIKONOV Physical Electronics Department Faculty of PhysicsLomonosov Moscow State University119991 MoscowRussia Research Institute for Graphite-Based Structural Materials‘Nllgrafit’ 1524 MoscowRussia

In this work we carried out an experimental investigation into enhancement of the sorption capacity of carbon fabric using plasma treatment *** fabric is based on viscose fiber and is hydrophobic by *** of the fabric sorption capacity is required for its application in *** this purpose,two plasma treatment methods were considered,*** nonequilibrium radiofrequency(RF)discharge and a vacuum RF plasma source with an external magnetic *** treated by atmospheric discharge demonstrated aging effects during the first week after *** sorption capacity of samples treated by the RF plasma source was stable over the same period and reached values as high as *** of the beam created by the vacuum RF plasma source were analyzed and dependences of the fabric sorption capacity and specific surface area on plasma treatment time were *** found that sorption capacity reached its maximum value after 30 min of treatment and did not change significantly if processing was continued,while the specific surface area reached its maximum after 3 min of treatment and quickly decreased after *** was found that the micropore structure of the fabric remained almost the same during plasma *** volume of mesopores in a unit of the fabric mass(specific volume)doubled during the first 5 min of treatment and returned to initial values after 30 min of *** sorption capacity continued to increase even when the specific surface area decreased after reaching its peak *** indicates the important role of surface functional groups formed on carbon fibers during plasma *** is consistent with the results of x-ray photoelectron spectroscopy analysis showing changes in surface oxidation during plasma treatment.

关键词： carbon fabric sorption plasma treatment radiofrequency

Altitude-dependent distribution of 137Cs in the environment:a case study of Aragats massif, Armenia

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Acta Geochimica 2020年第1期39卷 127-138页

作者： konstantin Pyuskyulyan Stephen P.LaMont Vovik Atoyan Olga Belyaeva Nona Movsisyan Armen Saghatelyan Armenian Nuclear Power Plant MetsamorArmenia Nuclear and Radiochemistry Los Alamos National LaboratoryLos AlamosUSA Radioecology Department Center for Ecological-Noosphere StudiesNAS RA.YerevanArmenia

This paper considers the distribution of technogenic 137Cs and naturally occurring radionuclides:238 U,232 Th and40 R concentrations in soils and 137Cs in atmospheric dry depositions by altitudinal belts of the Aragats mountain massif,Republic of *** soil samples were collected at altitudes from 1000 to 3200 *** the determination of geochemical variability,two soil sampling campaigns were *** dry depositions were sampled from five stations at1100-3200 m collected onto organic fiber filters between June and December 2016.137Cs activity was measured using a high-purity Germanium detector coupled to a multichannel analyzer(Canberra).Results indicated that specific activity of 137Cs in soils at 1000 m is495-528 Bq m^-2,andat3200 mis10,500-11,470 Bq m^-*** correlation observed for 137Cs versus naturally occurring radionuclides,which varies in distribution by *** activities of 137Cs in dry atmospheric depositions varies from 1.06 at 846 m to2.37 Bq m^-2 per quarter at 3200 m and increases as the altitude *** of 137Cs in soil and dry atmospheric deposition correlated significantly,and 137Cs activity in soils and atmospheric dry depositions decrease as the absolute altitude *** 50-year effective dose from exposure to 137Cs fallout varies with altitude from 0.007 to 1.42 m Sv.

关键词： 137Cs Distribution by altitude Naturally occurring radionuclides Topsoil Dry atmospheric depositions Gamma radiation Mountain regions

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土石坝竖向排水的渗流控制(英文)

岩土工程学报 2008年第11期30卷 1657-1660页

作者： Abdelkader Djehiche konstantin Kotchev L.G.C.U. Amar Telidji University Laghouat 03000 Laghouat Algeria Potyteehniea Sofia Bulgaria

水流通过坝体和坝基时存在压力和梯度,这在大坝工程设计中已视为重要因素。但是,在土石坝设计时往往会遇到抵御不利大坝安全因素的排水系统的选型和设计问题。目前,很多工程中虽存在一些效果不错的排水系统,但其缺乏渗流和浸润线位置的... 详细信息

水流通过坝体和坝基时存在压力和梯度,这在大坝工程设计中已视为重要因素。但是,在土石坝设计时往往会遇到抵御不利大坝安全因素的排水系统的选型和设计问题。目前,很多工程中虽存在一些效果不错的排水系统,但其缺乏渗流和浸润线位置的控制,可能会对工程安全产生威胁,或使渗流控制措施达不到经济有效的目的。为此,本文基于均质土坝实验研究取得的成果,研究出在竖向排水体中的渗流量的控制方法,采用这种方法可以对土石坝进行更好的管理。

关键词：渗流土石坝竖向排水排水体位置流量

Promoter methylation status of hMLH1,MGMT,and CDKN2A/p16 in colorectal adenomas

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World Journal of Gastroenterology 2010年第28期16卷 3553-3560页

作者： Vasiliki Psofaki Chryssoula Kalogera Nikolaos Tzambouras Dimitrios Stephanou Epameinondas Tsianos konstantin Seferiadis Georgios Kolios Laboratory of Clinical Chemistry University of Ioannina Medical School45500 IoanninaGreece Laboratory of Biochemistry University Hospital of IoanninaLeoforos S.Niarchou45500 IoanninaGreece Hepatogastroenterology Unit of Internal Medicine University Hospital of IoanninaLeoforos S.Niarchou45500 IoanninaGreece Laboratory of Pathology University Hospital of IoanninaLeoforos S.Niarchou45500 IoanninaGreece

AIM:To investigate aberrant DNA methylation of CpG islands and subsequent low-or high-level DNA microsatellite instability(MSI)which is assumed to drive colon carcinogenesis. METHODS:DNA of healthy individuals,adenoma(tu-bular or villous/tubulovillous)patients,and colorectal carcinoma patients who underwent colonoscopy was used for assessing the prevalence of aberrant DNA methylation of human DNA mismatch repair gene mutator L homologue 1(hMLH1),Cyclin-dependent kinase inhibitor 2A(CDKN2A/p16),and O-6-methylguanine DNA methyltransferase(MGMT),as well as their rela- tion to MSI. RESULTS:The frequency of promoter methylation for each locus increased in the sequence healthy tissue/adenoma/*** showed the highest frequency in each *** and CDKN2A/p16 presented a statistically significant increase in promoter methylation between the less and more tumorigenic forms of colorectal adenomas(tubular vs tubullovillous and villous adenomas).All patients with tubulovillous/villous adenomas,as well as all colorectal cancer patients,showed promoter methylation in at least one of the examined *** findings suggest a potentially crucial role for methylation in the polyp/adenoma to cancer progres- sion in colorectal *** and methylation seem to be interdependent,as simultaneous hMLH1, CDKN2A/p16,and MGMT promoter methylation was present in 8/9 colorectal cancer patients showing the MSI phenotype. CONCLUSION:Methylation analysis of hMLH1,CD- KN2A/p16,and MGMT revealed specific methylation profiles for tubular adenomas,tubulovillous/villous adenomas,and colorectal cancers,supporting the use of these alterations in assessment of colorectal tumorigenesis.

关键词： Promoter methylation Microsatellite instability Human DNA mismatch repair gene mutator L homologue 1 O-6-methylguanine DNA methyltransferase Cyclin-dependent kinase inhibitor 2A

Nanoscopic Tip Sensors Fabricated by Gas Phase Etching of Optical Glass Fibers

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Photonic Sensors 2012年第4期2卷 331-339页

作者： Jorg BIERLICH Jens KOBELKE David BRAND konstantin KIRSCH Jan DELLITH Hartmut BARTELT IPHT Institute of Photonic Technology Albert-Einstein-Sir. 9 07745 Jena Germany EAH University of Applied Sciences Carl-Zeiss-Promenade 2 07745 Jena Germany

Silica-based fiber tips are used in a variety of spectroscopic, micro- or nano-scopic optical sensor applications and photonic micro-devices. The miniaturization of optical sensor systems and the technical implementation using optical fibers can provide new sensor designs with improved properties and functionality for new applications. The selective-etching of specifically doped silica fibers is a promising method in order to form complex photonic micro structures at the end or within fibers such as tips and cavities in various shapes useful for the all-fiber sensor and imaging applications. In the present study, we investigated the preparation of geometrically predefined, nanoscaled fiber tips by taking advantage of the dopant concentration profiles of highly doped step-index fibers. For this purpose, a gas phase etching process using hydrofluoric acid （HF） vapor was applied. The shaping of the fiber tips was based on very different etching rates as a result of the doping characteristics of specific optical fibers. Technological studies on the influence of the etching gas atmosphere on the temporal tip shaping and the final geometry were performed using undoped and doped silica fibers. The influence of the doping characteristics was investigated in phosphorus-, germanium-, fluorine- and boron-doped glass fibers. Narrow exposed as well as protected internal fiber tips in various shapes and tip radiuses down to less than 15 nm were achieved and characterized geometrically and topologically. For investigations into surface plasmon resonance effects, the fiber tips were coated with nanometer-sized silver layers by means of vapour deposition and finally subjected to an annealing treatment.

关键词： Optical fiber tips nanoprobes gas phase etching doping tip shaping metal coating

Study on Stability and Efficiency of High-Power Ultrawideband Radiation Source

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Journal of Energy and Power Engineering 2012年第5期6卷 771-776页

作者： Vladimir I. koshelev Yury A. Andreev Anatoly M. Efremov Boris M. Kovalchuk Vyacheslav V. Plisko konstantin N. Sukhushin Shuhua Liu Microwave Electronics Laboratory and Pulsed Power Department Institute of High Current Electronics SB RAS Tomsk 634055Russia High Current Electronics Department at the Institute of High Technology Physics National Research Tomsk PolytechnicUniversity Tomsk 634050 Russia

Investigations are directed to the development of high-power sources ofUWB （ultrawideband） radiation based on excitation of anterma arrays with bipolar voltage pulses. In the previously designed high-power UWB sources only one bipolar pulse former and different feeder systems for pulse distribution through the array elements were used. By means of this approach, a number of UWB sources were created with the bipolar voltage pulse length ranging from 0.2 to 2 ns and effective potential of radiation ranging from 0.4 to 3 MV. The approach has got a restriction related to the electrical breakdown in a bipolar voltage pulse former. A new approach to the creation of high-power UWB sources based on a multicharmel bipolar pulse former is suggested： the number of bipolar pulse formers is equal to the number of antennas in the array. The main problem in realization of this approach is a stable operation of bipolar pulse formers in order to ensure a coherent summation of radiated pulses in the far-field zone. The result of this work is the instability of-150 ps at the pulse length of 3 ns obtained in a one-channel bipolar pulse former indicating that the suggested approach is realizable.

关键词： Monopolar pulse generator bipolar pulse former combined transmitting antenna ultrawideband radiation.

Predictive Inverse Neurocontrol:an experimental case study

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Journal of Harbin Institute of Technology(New Series) 2008年第1期15卷 109-112页

作者： konstantin Zmeu Boris Notkin 李胜波 Vyacheslav Stepaniuk Pavel Dyachenko Far Eastern State Technical University Automated Manufacturing System Department10 PushkinskayaVladivostok690950Russia Mechanical Engineering School Heilongjiang Institute of Science and Technology

To increase predictive behaviors of neural network dynamic model, an experimental case study of a new approach to systems controller design is presented. The experiment is based on neural networks inverse plant model. Special rules for network training are developed. Such system is close to model-based predictive control, but needs much less computational resources. The approach advantages are shown by the control of laboratory complex plants.

关键词： predictive control inverse control neural networks inverse plant model

Acoustic plasmonics of Au grating/Bi2Se3 thin film/sapphire hybrid structures

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Chinese Physics B 2020年第6期29卷 49-53页

作者： Weiwu Li konstantin Riegel Chuanpu Liu Alexey Taskin Yoichi Ando Zhimin Liao Martin Dressel Yuan Yan Physikalisches Institut Universitat StuttgartPfaffenwaldring 5770550 StuttgartGermany State Key Laboratory for Mesoscopic Physics School of PhysicsPeking UniversityBeijing 100871China Physics Institute II University of Cologne50937 KolnGermany Physikalisches Institut der Universitat Wurzburg 97074 WurzburgGermany Institute for Topological Insulators 97074 WurzburgGermany

The surface plasmon polaritons of the topological insulator Bi2Se3 can be excited by using etched grating or grave structures to compensate the wave vector mismatch of the incident photon and plasmon. Here, we demonstrate novel gold grating/Bi2Se3 thin film/sapphire hybrid structures, which allow the excitation of surface plasmon polaritons propagating through nondestructive Bi2Se3 thin film with the help of gold diffractive gratings. Utilizing periodic Au surface structures,the momentum can be matched and the normal-incidence infrared reflectance spectra exhibit pronounced dips. When the width of the gold grating W(with a periodicity 2 W) increases from 400 nm to 1500 nm, the resonant frequencies are tuned from about 7000 cm-1 to 2500 cm-1. In contrast to the expected ■ dispersion for both massive and massless fermions,where q ~π/W is the wave vector, we observe a sound-like linear dispersion even at room temperature. This surface plasmon polaritons with linear dispersion are attributed to the unique noninvasive fabrication method and high mobility of topological surface electrons. This novel structure provides a promising application of Dirac plasmonics.

关键词： surface plasmon polaritons topological insulator infrared optoelectronics nanophotonics