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真核基因启动子非依赖的功能转录延伸复合物的体外组装(英文)

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生物化学与生物物理进展 2006年第10期33卷 1000-1006页

作者：刘巍峰 SVEJSTRUP Q jesper 山东大学生命科学学院微生物技术国家重点实验室济南250100 Clare Hall Laboratories London Research InstituteCancer Research UKEN6 3LDUnited Kingdom

真核生物RNA聚合酶Ⅱ的持续合成能力对基因转录过程中每一个阶段,包括启动子脱离、转录暂停、转录终止以及转录偶联DNA损伤修复过程的调节至关重要.在RNA聚合酶Ⅱ介导的转录延伸过程中,其和模板DNA及转录产物RNA紧密结合,形成一个非常... 详细信息

真核生物RNA聚合酶Ⅱ的持续合成能力对基因转录过程中每一个阶段,包括启动子脱离、转录暂停、转录终止以及转录偶联DNA损伤修复过程的调节至关重要.在RNA聚合酶Ⅱ介导的转录延伸过程中,其和模板DNA及转录产物RNA紧密结合,形成一个非常稳定的延伸三维复合物(elongationcomplex,EC).此特征性“泡”状结构的形成是RNA聚合酶Ⅱ持续合成能力所必需的.在不依赖启动子及众多转录起始因子的条件下,利用人工合成的RNA与DNA寡核苷酸,在体外组装形成具有功能转录活性的延伸复合物.结果表明,长度为9个核苷酸的RNA与模板DNA形成的杂合分子对转录延伸复合物的形成是必需的,而非转录模板DNA链的加入导致最终活性转录“泡”状复合物的形成,并可转录形成与模板相关的转录产物,进一步通过在模板DNA的特定位置引入一个乙酰氧乙酰氨基芴修饰基团,可特异性地阻断转录延伸过程,从而显示该系统在研究真核基因转录及转录偶联DNA损伤修复机制中的潜在应用价值.

关键词： RNA聚合酶转录延伸复合物 TCR

Design and Simulation of a Feedback Control System for a Steel Plate Storage

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厦门大学学报（自然科学版） 2002年第S1期41卷 199-200页

作者： Torben Feld Holmgaard Kristensen Hans Holm jesper Hansen Department of Production Aalborg UniversityDepartment of Production Aalborg UniversityDepartm ent of Mathematical ModellingTechnical University of Denmark DenmarkDenmarkDenmark

A discrete event heuristic feedback control system fo r a steel plate storage at Odense Steel Shipyard Ltd is developed and implemente d in a computer-based simulation model. The plant is subject to stochastic dist urbances. The control system is able to handle this stochastic behaviour bec ause of the feedback design. The present simulation results indicate that a bene fit in the range of 30%～40% is reachable by modifying the plant. Plant description The steel plate storage is located at Odense Steel Shipyard Ltd, Denmark. The st eel plate storage contains steel plates used to build ship sections. The size of the storage is 600x35 meters. It consists of 32x8 stacks of plates. Plates are delivered and removed dynamically. The plate storage contains 5.000 steel plates in average. Over time, new plates delivered to the storage replace plates removed from the storage. The maximum si ze of a plate is 17x4 meters with a weight of up to 22 tons. The plates are uniq ue and dedicated to a specific purpose but in average the 5 000 plates consist o f 2 500 types. Plates are transported around the plate storage by two portal cranes. The cranes drive on a common rail and hence they cannot overtake each other. The cranes us e magnetic force to lift the plates. The crane can deliver the lifted plate to a conveyor belt or to another stack depending on whether the plate has been order ed for the current day or later. The plant is subject to different kinds of disturbances. The processes performed at the plant are stochastic. Furthermore, the due dates of the plates are frequ ently changed and hence the effect of previously sorting might be lost. The control task is to dispatch movements of plates to the two cranes. The overa ll goal is to minimize the costs at the plate storage and hence the two cranes a re used for executing the movements as fast as possible without colliding and re spect other physical constraints. Problem solution Different approaches have been investigated to s

关键词： Feedback stochastic heuristic deliver handle hence behaviour today replace removed

Analysis of Structure Transition and Compatibility of PTT/PC Blend without Transesterification

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Chinese Journal of Polymer Science 2016年第9期34卷 1172-1182页

作者： Qing-long Song 温慧颖 jesper de Claville Christiansen Dong-hong Yu Chun-sheng Chen 蒋世春 College of Engineering and Technology Northeast Forestry University Harbin 150040 China Department of Mechanical and Manufacturing Engineering Aalborg University DK-9220 Aalborg Denmark Department of Biotechnology Chemistry and Environmental Engineering Aalborg University DK-9220 Aalborg Denmark School of Materials Science and Engineering Tianjin University Tianjin 300072 China

Poly（trimethylene terephthalate）/polycarbonate （PTT/PC） blends were prepared by solvent mixing to avoid transesterification during high temperature blending. The influences of compositions on the thermal behavior, crystallization morphology and structure of the blends were studied. FTIR results indicated that there was no CO0 linking to two phenyl groups on each side chain and DSC results supported no transesterification reaction. DSC curves showed that Tc and Tmc increased to maximum range when PC contents were between 7 wt%-15 wt%, however, Tm decreased constantly with the increase of PC contents. It was observed from POM that PTT spherulitic morphology and crystallization kinetics were obviously influenced by the change of PC contents. Structural evolutions during cooling were investigated by SAXS which showed Lc of PTT remained a constant with different PC contents and also fixed during crystallization, nevertheless, it revealed a maximum value of Lnc for sample PTT93. It was concluded that PC chains could be permeated into not only amorphous crystallite structure but also amorphous lamellae structure and 7 wt% PC content was supposed to be the ＂proper＂ penetration amount into PTT lamellae structure which led to a maximum capacity of amorphous lamellar layer. Fringedmicelle crystal model was adopted to illustrate semi-crystalline physical structures of the blend in two kinds of component aggregation states.

关键词： Solvent mixing Transesterification Lamellae structure Fringed-micelle.

Strategies to obtain pattern fidelity in nanowire growth from large-area surfaces patterned using nanoimprint lithography

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Nano Research 2016年第10期9卷 2852-2861页

作者： Gaute Otnes Magnus Heurlin Mariusz Graczyk jesper Wallentin Daniel Jacobsson Alexander Berg Ivan Maximov Magnus T. Borgstrom Solid State Physics Lund University Box 118 S-22100 Lund Sweden

Position controlled nanowire growth is important for nanowire-based optoelectronic components which rely on light emission or light absorption. For solar energy harvesting applications, dense arrays of nanowires are needed; however, a major obstacle to obtaining dense nanowire arrays is seed particle displacement and coalescing during the annealing stage prior to nanowire growth. Here, we explore three different strategies to improve pattern preservation of large-area catalyst particle arrays defined by nanoimprint lithography for nanowire growth. First, we see that heat treating the growth substrate prior to nanoimprint lithography improves pattern preservation. Second, we explore the possibility of improving pattern preservation by fixing the seed particles in place prior to annealing by modifying the growth procedure. And third, we show that a SiNx growth mask can fully prevent seed particle displacement. We show how these strategies allow us to greatly improve the pattern fidelity of grown InP nanowire arrays with dimensions suitable for solar cell applications, ultimately achieving 100% pattern preservation over the sampled area. The generic nature of these strategies is supported through the synthesis of GaAs and GaP nanowires.

关键词： semiconductor nanowire nanoimprint lithography metal-organic vaporphase epitaxial (MOVPE) patterning

Ultrasensitive electrolyte-assisted temperature sensor

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npj Flexible Electronics 2020年第1期4卷 203-209页

作者： Mina Shiran Chaharsoughi jesper Edberg Peter Andersson Ersman Xavier Crispin Dan Zhao Magnus P.Jonsson Laboratory of Organic Electronics Department of Science and TechnologyLinköping UniversitySE-60174NorrköpingSweden RISE Research Institutes of Sweden Bio-and Organic ElectronicsBredgatan 3360221NorrköpingSweden

Heat sensors form an important class of devices that are used across multiple fields and *** applications such as electronic skin and health monitoring,it is particularly advantageous if the output electronic signals are not only high,stable,and reproducible,but also self-generated to minimize power ***,we present an ultrasensitive heat sensing concept that fulfills these criteria while also being compatible with scalable low-cost manufacturing on flexible *** concept resembles a traditional thermocouple,but with separated electrodes bridged by a gel-like electrolyte and with orders of magnitudes higher signals(around 11 mV K^(−1)).The sensor pixels provide stable and reproducible signals upon heating,which,for example,could be used for heat *** modification to plasmonic nanohole metasurface electrodes made the sensors capable of also detecting light-induced ***,we present devices on flexible substrates and show that they can be used to detect human touch.

关键词： electrolyte sensor heating

Deafblindness and dual sensory loss research: Current status and future directions

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World Journal of Otorhinolaryngology 2015年第2期5卷 37-40页

作者： jesper Dammeyer Department of Psychology University of Copenhagen

Deafblindness is more than the addition of hearing impairment plus vision impairment. The absence or impairment of both distance senses gives a condition which is more disabling than the sum of each. Deafblindness is rare among young people but becomes frequent at higher ages. Deafblindness can be either congenital or acquired. The heterogeneity of the population has been reported to be huge. Different levels of vision and hearing loss, different use of language modality, different kinds and severity of additional disabilities, and different medical aetiology are some of the variables splitting the group. Research in deafblindness is still in it is advent due to a number of limitations and a lack of current scientific interest. Some of the challenges in deafblindness research are： lack of consensus on the definition of deafblindness; rareness of the condition which makes it diffcult to even gather just a small group to study; heterogeneity of the population; difficulties with using traditional functional assessment procedures; communication barriers; and the difficulties of interpretation of deafblind behavior. This editorial calls for more interest in deafblindness in general and for more international cooperation and innovative studies to overcome existing barriers：Cooperation on data collection to form big enough sample sizes; development of reliable and valid tests and assessment tools; development of new research methods and approaches.

关键词： Deafblindness Dual sensory loss Dual sensory impairment Defnition Methodology

Large-energy-shift photon upconversion in degenerately doped InP nanowires by direct excitation into the electron gas

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Nano Research 2013年第10期6卷 752-757页

作者： Kilian Mergenthaler Azhar Iqbal jesper Wallentin Sebastian Lehmann Magnus T. Borgstrom Lars Samuelson Arkady Yartsev Mats-Erik Pistol Solid State Physics/The Nanometer Structure Consortium Lund University P. O. Box 118 SE-22100 Lund Sweden Division of Chemical Physics Lund University P O. Box 118 SE-22100 Lund Sweden

Realizing photon upconversion in nanostructures is important for many next- generation applications such as biological labelling, infrared detectors and solar cells. In particular nanowires are attractive for optoelectronics because they can easily be electrically contacted. Here we demonstrate photon upconversion with a large energy shift in highly n-doped InP nanowires. Crucially, the mechanism responsible for the upconversion in our system does not rely on multi-photon absorption via intermediate states, thus eliminating the need for high photon fluxes to achieve upconversion. The demonstrated upconversion paves the way for utilizing nanowires--with their inherent flexibility such as electrical contactability and the ability to position individual nanowires--for photon upconversion devices also at low photon fluxes, possibly down to the single photon level in optimised structures.

关键词： nanowires photon upconversion photoluminescence indium phosphide

Range Extension and Channel Capacity Increase in Impulse-Radio Ultra-Wideband Communications

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Tsinghua Science and Technology 2010年第2期15卷 169-173页

作者： Roberto Rodes Antonio Caballero jesper Bevensee Jensen Timothy Braidwood Gibbon Neil Guerrero Gonzalez Idelfonso Tafur Monroy DTU Fotonik Department of Photonics Engineering Technical University of Denmark

We theoretically analyze the channel capacity of a 5th-order Gaussian pulse-based ultra-wideband （UWB） system and experimentally demonstrate 2 Gbit/s UWB-over-fiber transmission systems incorporating wireless transmission. Both electrical and photonic UWB pulse generation methods are employed and its performance is compared. By utilizing optimum UWB pulse design and employing a digital signal processing （DSP） receiver, a bit-error-rate above the forward error correction （FEC） limit for 8 meters of wireless＇emis- sion is obtained in our photonic generation UWB system. A noticeable increase in the channel capacity is achieved compared to previously reported results.

关键词： impulse radio ultra-wideband UWB-over-fiber channel capacity personal area networks

Developed Numerical Simulation of Falling and Moving Objects in Viscous Fluids under the Action of a Reynolds Lubrication Theory and Low Reynolds Numbers

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Open Journal of Fluid Dynamics 2020年第1期10卷 8-30页

作者： Seema Paul jesper Oppelstrup Department of Scientific Computing Royal Institute of Technology Stockholm Sweden Department of Sustainable Development Environmental Science and Engineering Royal Institute of Technology Stockholm Sweden

The development work focuses on the numerical simulations of free body movement in viscous fluid. The aim is to make the simulation of very slow motion of the small body in viscous fluid. We developed bodies’ immersed dynamics simulations in viscous fluid by seeking numerical solutions for appropriate field variables. We developed the methods for vertically and spherically cylindrical objects’ motions, the forces on bodies close to a plane stationary wall are computed from the velocity and pressure fields using the Stokes equation through COMSOL Multiphysics finite element software. The Navier-Stokes equation is reduced to Stokes equation there is independence of time which means object will have an effect only on the motion and the slightly compressible flow assumption is made in order to obtain smooth solution numerically. The forces on an object in slightly compressible Stokes flow have been exerted on the falling objects. The resulting forces have compared with analytical results from the Reynolds Lubrication Theory, and achieved significant results from the development method in Matlab and achieved significant numerical simulations in COMSOL. In addition, an investigation has been made to an object swimming at low Reynolds number. At low Reynolds number moving is possible when object scale is small and flow pattern is slow and sticky. We have developed a system for a thin two-dimensional (2D) worm-like object wiggle that is passing a wave along its centreline and its motion has simulated by the Ordinary Differential Equations (ODE) system and by the Arbitrary Lagrangian-Eulerian (ALE) moving mesh technology. The development method result shows that it is possible for the small object to have a motion from one position to another through small amplitudes and wavelengths in viscous fluid.

关键词： Slightly Compressible Stokes Equation Reynolds Lubrication Theory Falling and Moving Objects Moving Mesh Low Reynold Swimming