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1.
G. Bilchev R. Venousiou J. Foley P. Benyon S. Case G. Churcher 《BT Technology Journal》2005,23(3):226-238
This paper describes the ePerSpace research project which aims to significantly increase user acceptance of networked audiovisual systems and applications at home and virtually anywhere by enabling innovative interoperable value-added personalised networked services and applications. Moreover, it aims to develop an open architecture and a framework that will significantly increase the speed of developing novel value-added personalised services by reusing well-defined system components with open APIs. The structure of the paper follows the methodology of the project. It starts with a vision of future personalised services from the users’ perspective by developing five scenarios. These scenarios are then used to extract the requirements of the personalisation framework which is then described in terms of its personalisation, service management, digital home environment management and content adaptation capabilities. 相似文献
2.
3.
Peroxide crosslinking of unplasticized poly(vinyl chloride) with trimethylolpropane trimethacrylate was investigated. Formulations used in this work contained a nontoxic lead‐free stabilizer and showed good color and heat stability. The samples were examined by differential scanning calorimetry, and their tensile properties were measured at room temperature and at 130°C. Gel content or tetrahydrofuran‐insoluble material was measured as an indication of crosslinking. It was shown that premature crosslinking could be avoided during processing and that 190°C was the optimum processing temperature for maximum gel content. The residual unsaturation was monitored by using FTIR spectroscopy. J. VINYL ADDIT. TECHNOL., 2008. © 2008 Society of Plastics Engineers 相似文献
4.
Yilin Han Marianne King Evgenii Tikhomirov Povilas Barasa Cleide Dos Santos Souza Jonas Lindh Daiva Baltriukiene Laura Ferraiuolo Mimoun Azzouz Maurizio R. Gullo Elena N. Kozlova 《International journal of molecular sciences》2022,23(10)
Three-dimensional (3D) cultures, so-called organoids, have emerged as an attractive tool for disease modeling and therapeutic innovations. Here, we aim to determine if boundary cap neural crest stem cells (BC) can survive and differentiate in gelatin-based 3D bioprinted bioink scaffolds in order to establish an enabling technology for the fabrication of spinal cord organoids on a chip. BC previously demonstrated the ability to support survival and differentiation of co-implanted or co-cultured cells and supported motor neuron survival in excitotoxically challenged spinal cord slice cultures. We tested different combinations of bioink and cross-linked material, analyzed the survival of BC on the surface and inside the scaffolds, and then tested if human iPSC-derived neural cells (motor neuron precursors and astrocytes) can be printed with the same protocol, which was developed for BC. We showed that this protocol is applicable for human cells. Neural differentiation was more prominent in the peripheral compared to central parts of the printed construct, presumably because of easier access to differentiation-promoting factors in the medium. These findings show that the gelatin-based and enzymatically cross-linked hydrogel is a suitable bioink for building a multicellular, bioprinted spinal cord organoid, but that further measures are still required to achieve uniform neural differentiation. 相似文献
5.
Florian Turbant Jehan Waeytens Camille Campidelli Marianne Bombled Denis Martinez Axelle Grlard Birgit Habenstein Vincent Raussens Marisela Velez Frank Wien Vronique Arluison 《International journal of molecular sciences》2022,23(15)
Hfq is a pleiotropic regulator that mediates several aspects of bacterial RNA metabolism. The protein notably regulates translation efficiency and RNA decay in Gram-negative bacteria, usually via its interaction with small regulatory RNAs. Previously, we showed that the Hfq C-terminal region forms an amyloid-like structure and that these fibrils interact with membranes. The immediate consequence of this interaction is a disruption of the membrane, but the effect on Hfq structure was unknown. To investigate details of the mechanism of interaction, the present work uses different in vitro biophysical approaches. We show that the Hfq C-terminal region influences membrane integrity and, conversely, that the membrane specifically affects the amyloid assembly. The reported effect of this bacterial master regulator on membrane integrity is discussed in light of the possible consequence on small regulatory RNA-based regulation. 相似文献
6.
Zsfia Ilona Szojka Sara Karlson Emil Johansson Gülen
zkaya ahin Marianne Jansson 《International journal of molecular sciences》2022,23(9)
HIV-2, compared to HIV-1, elicits potent and broadly neutralizing antibodies, and uses a broad range of co-receptors. However, both sensitivity to neutralization and breadth of co-receptor use varies between HIV-2 isolates, and the molecular background is still not fully understood. Thus, in the current study, we have deciphered relationships between HIV-2 neutralization sensitivity, co-receptor use and viral envelope glycoprotein (Env) molecular motifs. A panel of primary HIV-2 isolates, with predefined use of co-receptors, was assessed for neutralization sensitivity using a set of HIV-2 Env-directed monoclonal antibodies and co-receptor indicator cell lines. Neutralization sensitivity of the isolates was analysed in relation target cell co-receptor expression, in addition to amino acid motifs and predicted structures of Env regions. Results showed that HIV-2 isolates were more resistant to neutralizing antibodies when entering target cells via the alternative co-receptor GPR15, as compared to CCR5. A similar pattern was noted for isolates using the alternative co-receptor CXCR6. Sensitivity to neutralizing antibodies appeared also to be linked to specific Env motifs in V1/V2 and C3 regions. Our findings suggest that HIV-2 sensitivity to neutralization depends both on which co-receptor is used for cell entry and on specific Env motifs. This study highlights the multifactorial mechanisms behind HIV-2 neutralization sensitivity. 相似文献
7.
Ö. Unal I. E. Anderson J. L. Harringa R. L. Terpstra B. A. Cook J. C. Foley 《Journal of Electronic Materials》2001,30(9):1206-1213
The asymmetrical four-point bend shear (AFPB) test method was used to measure the shear strength and creep properties through
the stress relaxation experiments using three different Pb-free solder joint compositions in an assolidified condition. Since
it was difficult to shear the uniform specimens and the local bending usually occurs at the inner loading points, the notches
were introduced at the joint line to preferentially weaken this region. The stress analysis by finite element modeling showed
that the straight notches transform the parabolic shear stress distribution in the uniform specimen into a relatively uniform
shear distribution along the bond line in the notched specimens. Therefore, the shear strength results from the notched specimens
are expected to be much more accurate. Experiments showed that both the Sn-3.6Ag-1Cu (wt.%) and Sn-3.6Ag-1Cu-0.45Co joints
have superior strength and creep properties as compared to the Sn-3.5Ag joint. However, there was no statistical difference
between the shear strength of the Sn-3.6Ag-1Cu and Sn-3.6Ag-1Cu-0.45 Co joints. Moreover, the difference between the creep
resistance of these two types of joints was small. 相似文献
8.
Photoluminescence: Design and Integration in Electro‐Optic Devices of Highly Efficient and Robust Red‐NIR Phosphorescent Nematic Hybrid Liquid Crystals Containing [Mo6I8(OCOCnF2n+1)6]2− (n = 1, 2, 3) Nanoclusters (Adv. Funct. Mater. 31/2015) 下载免费PDF全文
9.
This paper is concerned with the subjective perception of video coding artifacts in H.264/AVC encoded and decoded video. Our objective is to model the perceived annoyance of such low bit rate video sequences as a function of perceived artifact strength. We introduce a new method for determining this function and apply it to the data from two psychophysical experiments. Both experiments produced numerical judgments of the subjectively perceived annoyance of artifact combinations and the perceived strength of the respective coding artifacts. Our method produces a discrete multi-dimensional representation of the relationships in the data from which the function relating annoyance to artifact strength is derived. The method is applied to the data of the first experiment and the resulting function is shown to describe the data from the second experiment as well. 相似文献
10.
Adeline Lanterne Jrme Le Perchec Samuel Gall Sylvain Manuel Marianne Coig Aurlie Tauzin Yannick Veschetti 《Progress in Photovoltaics: Research and Applications》2015,23(11):1458-1465
Ion implantation has the advantage of being a unidirectional doping technique. Unlike gaseous diffusion, this characteristic highlights strong possibilities to simplify solar cell process flows. The use of ion implantation doping for n‐type PERT bifacial solar cells is a promising process, but mainly if it goes with a unique co‐annealing step to activate both dopants and to grow a SiO2 passivation layer. To develop this process and our SONIA cells, we studied the impact of the annealing temperature and that of the passivation layers on the electrical quality of the implanted B‐emitter and P‐BSF. A high annealing temperature (above 1000 °C) was necessary to fully activate the boron atoms and to anneal the implantation damages. Low J0BSF (BSF contribution to the saturation current density) of 180 fA/cm2 was reached at this high temperature with the best SiO2 passivation layer. An average efficiency of 19.7% was reached using this simplified process flow (“co‐anneal process”) on large area (239 cm2) Cz solar cells. The efficiency was limited by a low FF, probably due to contaminations by metallization pastes. Improved performances were achieved in the case of a “separated anneals” process where the P‐BSF is activated at a lower temperature range. An average efficiency of 20.2% was obtained in this case, with a 20.3% certified cell. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献