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41.
The leucine-rich nuclear export signal (NES) is used by a variety of proteins to facilitate their delivery from the nucleus to the cytoplasm. One of the best-studied examples, protein kinase inhibitor (PKI), binds to the catalytic subunit of protein kinase A in the nucleus and mediates its rapid export to the cytoplasm. We developed a permeabilized cell assay that reconstitutes nuclear export mediated by PKI, and we used it to characterize the cytosolic factors required for this process. The two-step assay involves an import phase and an export phase, and quantitation is achieved by digital fluorescence microscopy. During the import phase, a fluorescent derivative of streptavidin is imported into the nuclei of digitonin-permeabilized HeLa cells. During the export phase, biotinylated PKI diffuses into the nucleus, binds to fluorescent streptavidin, and mediates export of the complex to the cytoplasm. Nuclear export of the PKI complex is cytosol dependent and can be stimulated by addition of the purified NES receptor, Crm1. HeLa cell cytosol treated with N-ethylmaleimide (NEM) or phenyl-Sepharose to inactivate or deplete Crm1, respectively, is still fully active in the PKI export assay. Significantly, the export activity can be depleted from cytosol by preadsorption with a protein conjugate that contains a functional NES. These data indicate that cytosol contains an export activity that is distinct from Crm1 and is likely to correspond to an NES receptor. 相似文献
42.
This paper deals with modelling and performance of adjustable speed drives (ASDs) subjected to voltage disturbances in electric supply. The aim of this study was to develop appropriate models of typical ASD and investigate their sensitivity to voltage disturbances under various practical modes of operation and control. Accordingly, scalar controlled open and closed loop volts–hertz (V–Hz) and vector controlled closed loop ASDs are modelled in PSCAD/EMTDC environment, and their performance in the presence of voltage disturbances is investigated under typical operating and loading conditions. 相似文献
43.
44.
The purpose of this paper is to present an algorithm developed for real-time estimation of skeletal muscle ischemia, based on parameters extracted from in vivo obtained electrical impedance spectra. A custom impedance spectrometer was used to acquire data sets: complex impedance spectra measured at 27 frequencies in the range of 100 Hz-1 MHz, and tissue pH. Twenty-nine in vivo animal studies on rabbit anterior tibialis muscle were performed to gather data on the behavior of tissue impedance during ischemia. An artificial neural network (ANN) was used to quantitatively describe the relationship between the parameters of complex tissue impedance spectra and tissue ischemia via pH. The ANN was trained on 1249, and tested on 946 ischemic tissue impedance data sets. A correlation of 94.5% and a standard deviation of 0.15 pH units was achieved between the ANN estimated pH and measured tissue pH values. 相似文献
45.
Nikola Bulatović Nikola Žarić Slobodan Djukanović Igor Radusinović Milica Pejanović-Djurišić 《Wireless Personal Communications》2017,92(1):237-250
The paper addresses the Be Responsible platform, a representative example of human-centric sensing network which, relying on the Info-Communication and Internet of Things concepts, aims to improve the communication between citizens, on one side, and government authorities, on the other side, with the purpose of resolving various problems encountered in a modern society. A widespread network of human-centric smartphone devices and PCs has been used as a valuable source of data collected and processed in order to trigger adequate actions upon problem resolving. In this way, humans acting as sensor operators and data sources become a powerful factor in improving their society. The Be Responsible platform enables the people to report the irregularities in various aspects of their social life (grey economy, misuse of government vehicles, ecology, traffic), and hence to take active part in resolving them. It also promotes positive and responsible social and institutional behavior, which has to be nurtured in any society seeking progress. The number of submitted reports as well as the money collected from the fine revenues and subsequently invested in projects of social good, undoubtedly prove that what could not be achieved through years of traditional government-led policy approach, was achieved in months of citizen engagement. 相似文献
46.
47.
Dušan Barać Vanjica Ratković-Živanović Marijana Despotović-Zrakić Aleksandra Labus Zorica Bogdanović 《Telematics and Informatics》2017,34(1):20-29
This paper examines the possibilities of enhancing relationship management between public service broadcasters and their stakeholders by harnessing the potential of newest e-business technologies and concepts, such as: social media, digital and interactive TV, and mobile computing. In order to facilitate adoption of relationship management strategy, a framework for leveraging relationship management is proposed. Evaluation was performed within the e-business system of a public broadcaster. This empirical study explored the readiness and expected benefits of relationship management implementation. The research results have indicated that a public broadcaster could achieve a higher level of social responsibility, improve business sustainability, and empower communication and collaboration with all the stakeholders by using emerging technologies for relationship management activities. 相似文献
48.
U. V. Desnica B. Šantić Dunja I. Desnica M. Pavlović 《Journal of Electronic Materials》1993,22(4):403-407
Trapping and recombination of free carriers by deep level T3 has been studied. Occupancy of the level by electrons and dynamics of its filling and emptying as a function of illumination
with monoenergetic photons in 0.69–1.55 eV range has been monitored by the thermally stimulated currents method. We have found
that level T3 behaves more like a recombination center than like an ordinary electron trap. Besides trapping free electrons from conduction
band, this trap can also communicate with valence band, trapping holes. The capture cross section for trapping a hole is estimated
to be comparable or even larger than the capture cross section for trapping an electron. However, in many experimental conditions
free electrons are generated more abundantly than free holes, and free carrier mobility and thermal velocity are both much
higher for electrons than for holes. Therefore, electron trapping often prevails, so that this frequently detected defect,
has been up to now most often perceived as a deep electron trap. 相似文献
49.
For the given observations set of the ARMA (autoregressive moving average) process, the likelihood function depends, not only on model parameters, but on the starting values of the input and output. Therefore, it is called theconditional likelihood function. Theunconditional likelihood function can be obtained in two ways. The first is to set the starting values to zero, as is often done, and the second is to set them to the properly estimated values. The difference between these two types of likelihood functions is significant when the given data sequence is short, and any of the zeros of the moving average part is close to the boundary of the unit circle.In this paper the direct method of starting value estimation and its application to two off-line ARMA estimation algorithms, the maximum likelihood (ML) algorithm and the iterative inverse filtering (ITIF) algorithm, is proposed. Experimental results prove both increased efficiency and stability of these algorithms.The importance of setting the starting values properly is also significant when the recursive algorithm, with previously estimated parameters, has to be restarted. The advantage of the proposed reinitialization method is shown on the recursive lattice algorithm working in the block mode. 相似文献
50.
J. Chen V. Leblanc S. H. Kang P. J. Benning D. Schut M. A. Baldo M. A. Schmidt V. Bulović 《Advanced functional materials》2007,17(15):2722-2727
We introduce a high resolution molecular jet (MoJet) printing technique for vacuum deposition of evaporated thin films and apply it to fabrication of 30 μm pixelated (800 ppi) molecular organic light emitting devices (OLEDs) based on aluminum tris(8‐hydroxyquinoline) (Alq3) and fabrication of narrow channel (15 μm) organic field effect transistors (OFETs) with pentacene channel and silver contacts. Patterned printing of both organic and metal films is demonstrated, with the operating properties of MoJet‐printed OLEDs and OFETs shown to be comparable to the performance of devices fabricated by conventional evaporative deposition through a metal stencil. We show that the MoJet printing technique is reconfigurable for digital fabrication of arbitrary patterns with multiple material sets and high print accuracy (of better than 5 μm), and scalable to fabrication on large area substrates. Analogous to the concept of “drop‐on‐demand” in Inkjet printing technology, MoJet printing is a “flux‐on‐demand” process and we show it capable of fabricating multi‐layer stacked film structures, as needed for engineered organic devices. 相似文献