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231.
Human Cell Encapsulation in Gel Microbeads with Cosynthesized Concentric Nanoporous Solid Shells
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Xiamo Chianty Zhou Tommy Haraldsson Salvatore Nania Federico Ribet Giorgia Palano Rainer Heuchel Matthias Löhr Wouter van der Wijngaart 《Advanced functional materials》2018,28(21)
Encapsulation of therapeutic cells in core–shell microparticles has great promise for the treatment of a range of health conditions. Unresolved challenges related to control of the particle morphology, mechanical stability, and immunogenicity hinder dissemination of this promising approach. Here, a novel polymer material for cell encapsulation and a combined novel, easy to control, synthesis method are introduced. Core–shell cell encapsulation is demonstrated with a concentric core–shell morphology formed during a single UV exposure, resulting in particles that consist of a synthetic hydrogel core of polyethylene glycol diacrylate and a solid, but porous, shell of off‐stoichiometric thiol‐ene. The encapsulated human cells in 100 µm diameter particles have >90% viability. The average shell thickness is controlled between 7 and 13 µm by varying the UV exposure, and the shell is measured to be permeable to low molecular weight species (<180 Da) but impermeable to higher molecular weight species (>480 Da). The unique material properties and the orthogonal control of the microparticle core size, shell thickness, shell permeability, and shell surface properties address the key unresolved challenges in the field, and are expected to enable faster translation of novel cell therapy concepts from research to clinical practice. 相似文献
232.
Explorer(探索者)轴承系列是SKF公司最新研制的推力球面滚子轴承,新型的推力球面滚子轴承可以承受巨大的径向载荷加上轴向载荷。这种承受复合载荷的能力使传动结构的设计者在设计部件时既节约了成本, 相似文献
233.
Hui Zhang XiaoDong Xu JingYa Li XiaoFeng Tao Ping Zhang Tommy Svensson Carmen Botella 《中国科学F辑(英文版)》2009,52(12):2378-2384
As a new technology, coordinated multipoint (CoMP) transmission is included in LTE-Advanced study item. Moreover, the network
architecture in LTE-Advanced system is modified to take into account coordinated transmission. Under this background, a novel
power allocation game model is established to mitigate inter-cell interference with cellular coordination. In the light of
cellular cooperation relationship and centralized control in eNodeB, the power allocation in each served antenna unit aims
to make signal to interference plus noise ratio (SINR) balanced among inter-cells. Through the proposed power allocation game
algorithm, the users’ SINR can reach the Nash equilibrium, making it feasible to reduce the co-frequency interference by decreasing
the transmitted power. Numerical results show that the proposed power allocation algorithm improves the throughput both in
cell-center and cell-edge. Moreover, the blocking rate in cell-edge is reduced too. 相似文献
234.
Computational docking to nicotinic acetylcholine receptors (nAChRs) and other members of the Cys-loop receptor family is complicated by the flexibility of the so-called C-loop. As observed in the large number of published crystal structures of the acetylcholine binding protein (AChBP), a structural surrogate and homology modeling template for the nAChRs, the conformation of this loop is controlled by the ligand present in the binding pocket. As part of the development of a protocol for unbiased docking to the nAChRs, we here present the results of docking of ligands with known binding modes to an AChBP ensemble with systematic variations in C-loop closure generated via a series of targeted geometry optimizations. We demonstrate the ability to correctly predict binding modes for 12 out of 15 ligands and induced degrees of C-loop closure for 14 out of 15 ligands. Our approach holds a promising potential for structure based drug discovery within nAChRs and related receptors. 相似文献
235.
Gaspard Pardon Farizah Saharil J. Mikael Karlsson Omkar Supekar Carl Fredrik Carlborg Wouter van der Wijngaart Tommy Haraldsson 《Microfluidics and nanofluidics》2014,17(4):773-779
A new and easy-to-use method that allows for mold-free and rapid prototyping of microfluidic devices, comprising channels, access holes, and surface-modified patterns, is presented. The innovative method is based on direct photolithographic patterning of an off-stoichiometry thiol-ene (OSTE) polymer formulation, tailor-made for photolithography, which offers unprecedented spatial resolution and allows for efficient, robust and reliable, room temperature surface modification and glue-free, covalent room temperature bonding. This mold-free process does not require clean room equipment and therefore allows for rapid, i.e., less than one hour, design-fabricate-test cycles, using a material suited for larger-scale production. The excellent photolithographic properties of this new OSTE formulation allow patterning with unprecedented, for thiol-ene polymer systems, resolution in hundreds of micrometers thick layers, 200 μm thick in this work. Moreover, we demonstrated robust, covalent and spatially controlled modification of the microchannel surfaces with an initial contact angle of 76° by patterning hydrophobic/hydrophilic areas with contact angles of 102° and 43°, respectively. 相似文献
236.
A new approach for content-based image retrieval (CBIR) is described. In this study, a tree-structured image representation together with a multi-layer self-organizing map (MLSOM) is proposed for efficient image retrieval. In the proposed tree-structured image representation, a root node contains the global features, while child nodes contain the local region-based features. This approach hierarchically integrates more information of image contents to achieve better retrieval accuracy compared with global and region features individually. MLSOM in the proposed method provides effective compression and organization of tree-structured image data. This enables the retrieval system to operate at a much faster rate than that of directly comparing query images with all images in databases. The proposed method also adopts a relevance feedback scheme to improve the retrieval accuracy by a respectable level. Our obtained results indicate that the proposed image retrieval system is robust against different types of image alterations. Comparative results corroborate that the proposed CBIR system is promising in terms of accuracy, speed and robustness. 相似文献
237.
A people-counting system using hybrid RBF neural network is described. The proposed system is effective and flexible for the purpose of performing on-line people counting. Compared with other conventional approach, this system introduces a novel method for feature extraction. In this Letter, a new type of hybrid RBF network is developed to enhance the classification performance. The hybrid RBF based people-counting system is thoroughly compared with other approaches. Extensive and promising results were obtained and the analysis indicates that the proposed hybrid RBF based system provides excellent people-counting results in an open passage. A supervised clustering method is proposed for initialising the hybrid RBF network. In order to substantiate the introduction of the hybrid RBF and the proposed supervised clustering algorithm, test results on a vowel recognition benchmark dataset are also included in the Letter. 相似文献
238.
Levant Ronald F.; Moldawsky Stanley; Stigall Tommy T. 《Canadian Metallurgical Quarterly》2000,31(4):392
Reports an error in "The evolving profession of psychology: Comment on Lowe Hays-Thomas's (2000) "The silent conversation." by Ronald F. Levant, Stanley Moldawsky and Tommy T. Stigall (Professional Psychology: Research and Practice, 2000[Jun], Vol 31[3], 346-348). On page 346 in the author note, Louisiana Southern University was given as the university where Tommy T. Stigall received his PhD. The correct university is Louisiana State University. (The following abstract of the original article appeared in record 2000-03894-017.) The authors comment on R. Lowe Hays-Thomas (2000; see record 2000-03894-016). The article begins with a few comments about the master's-degree issue and then examines the evolution of professional psychology in relationship to the master's issue over the past 50 years and into the future. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
239.
240.
The private rental sector in Sweden is competing on a less-regulated and less-subsidized housing market. The paper analyses
the prospects of this sector. The private sector has the dual advantage of an older (more attractive and centrally located)
stock and a slightly beter-off tenant profile than the municipal sector. Thus, the private sector will be less affected by
the withdrawal of interest subsidies, as these were given to new stock. The rent-to-income ratio will surpass 30 per cent
in all sectors of the housing market in the year 2002, according to a recent projection. The private sector suffers less from
vacancies than the municipal sector. The economic situation is, however, characterized by high LTV ratios, due to a price
and borrowing boom in the late 1980s. This has led to bankruptcies and a weak economic situation for many private landlords.
The boom was followed by a bust in 1990–93. Both the upswing and the downturn can be explained by fundamentals such as changes
in GDP, unemployment, housing subsidy and tax rules. In the present recession, the private rental sector will benefit from
its large share of small dwellings, which will also be advantagenous in the longer run, in view of the demographic trend towards
more small households. There is fierce competition between the private and the municipal housing sector. In the short run,
the private sector will benefit from the removal of interest subsidies. The effects will be felt in the younger municipal
sector. All in all, both short-run and long-run considerations point at a housing market in Sweden which will keep its dualistic
character of free competition between the private and the municipal sector in the future.
Bengt Turner is Professor of Economics and Chair of the Institute for Housing Research at Uppsala University. He is also chairman of the
European Network for Housing Research and coordinates a working group on housing finance. His research area is housing policy,
microeconomic analysis of the housing market, as well as housing finance. He has also analysed the housing situation in transitory
(East European) countries. In Sweden he is actively involved in housing policy formation as an expert in Governmental commissions
and as a member of a number of research boards.
Tommy Berger is an economist at the Institute of Housing Research, Uppsala University. His main interest is in housing finance and taxation
policy. 相似文献