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排序方式: 共有140条查询结果,搜索用时 0 毫秒
1.
Farzaneh Fayazpour Bart Lucas Roosmarijn E. Vandenbroucke Stefaan Derveaux Jan Tavernier Sam Lievens Joseph Demeester Stefaan C. De Smedt 《Advanced functional materials》2008,18(18):2716-2723
To obtain more biologically relevant data there is a growing interest in the use of living cells for assaying the biological activity of unknown chemical compounds. Density ‘multiplex’ cell‐based assays, where different cell types are mixed in one well and simultaneously investigated upon exposure to a certain compound are beginning to emerge. To be able to identify the cells they should be attached to microscopic carriers that are encoded. This paper investigates how digitally encoded microparticles can be loaded with cells while keeping the digital code in the microcarriers readable. It turns out that coating the surface of the encoded microcarriers with polyelectrolytes using the layer‐by‐layer (LbL) approach provides the microcarriers with a ‘highly functional’ surface. The polyelectrolyte layer allows the growth of the cells, allows the orientation of the cell loaded microcarriers in a magnetic field, and does not hamper the reading of the code. It has further been shown that the cells growing on the polyelectrolyte layer can become transduced by adenoviral particles hosted by the polyelectrolyte layer. It is concluded that the digitally encoded microparticles are promising materials for use in biomedical and pharmaceutical in‐vitro research where cells are used as tools. 相似文献
2.
Erkan Aydin Michele De Bastiani Xinbo Yang Muhammad Sajjad Faisal Aljamaan Yury Smirnov Mohamed Nejib Hedhili Wenzhu Liu Thomas G. Allen Lujia Xu Emmanuel Van Kerschaver Monica Morales‐Masis Udo Schwingenschlgl Stefaan De Wolf 《Advanced functional materials》2019,29(25)
Parasitic absorption in transparent electrodes is one of the main roadblocks to enabling power conversion efficiencies (PCEs) for perovskite‐based tandem solar cells beyond 30%. To reduce such losses and maximize light coupling, the broadband transparency of such electrodes should be improved, especially at the front of the device. Here, the excellent properties of Zr‐doped indium oxide (IZRO) transparent electrodes for such applications, with improved near‐infrared (NIR) response, compared to conventional tin‐doped indium oxide (ITO) electrodes, are shown. Optimized IZRO films feature a very high electron mobility (up to ≈77 cm2 V?1 s?1), enabling highly infrared transparent films with a very low sheet resistance (≈18 Ω □?1 for annealed 100 nm films). For devices, this translates in a parasitic absorption of only ≈5% for IZRO within the solar spectrum (250–2500 nm range), to be compared with ≈10% for commercial ITO. Fundamentally, it is found that the high conductivity of annealed IZRO films is directly linked to promoted crystallinity of the indium oxide (In2O3) films due to Zr‐doping. Overall, on a four‐terminal perovskite/silicon tandem device level, an absolute 3.5 mA cm?2 short‐circuit current improvement in silicon bottom cells is obtained by replacing commercial ITO electrodes with IZRO, resulting in improving the PCE from 23.3% to 26.2%. 相似文献
3.
Stefaan J. H. Soenen Linda Desender 《International journal of environmental analytical chemistry》2013,93(10-11):783-796
The complex of diethylenetriaminepentaacetate (DTPA) with the paramagnetic gadolinium ion [Gd(III)] is a well-known blood pool contrast agent for magnetic resonance imaging (MRI). To obtain MRI pictures from other anatomical structures, for instance from tissues containing cells with phagocytic activity, larger colloidal complexes have to be constructed. Therefore, in view of modifying the physiological behaviour, the DTPA chelate was first hydrophobized by covalently linking it to phosphatidylethanolamine (PE), and the resulting conjugate was then incorporated into nanometre-sized, sonicated phospholipid vesicles. Qualitative information on the affinity of the PE–DTPA derivative for Gd(III) ions was derived from competition experiments using the dye Arsenazo. Furthermore, it was found that only the membranotropic adducts residing in the outer shell of the vesicle bilayer are accessible to the lanthanide ion. The vesicular particulate was also used as a vehicle to transport PE–DTPA into the coating of so-called magnetoliposomes which consist of nanometre-sized iron oxide cores onto which a phospholipid bilayer is strongly chemisorbed. After loading the resulting structures with Gd(III), this new type of magnetoliposome may offer unique potentialities as a novel bi-label MRI contrast medium. 相似文献
4.
5.
Eliane Bcache Grgoire Derveaux Patrick Joly 《Numerical Methods for Partial Differential Equations》2005,21(2):323-348
We solve numerically the Kirchhoff‐Love dynamic plate equation for an anisotropic heterogeneous material using a spectral method. A mixed velocity‐moment formulation is proposed for the space approximation allowing the use of classical Lagrange finite elements. The benefit of using high order elements is shown through a numerical dispersion analysis. The system resulting from this spatial discretization is solved analytically. Hence this method is particularly efficient for long duration experiments. This time evolution method is compared with explicit and implicit finite differences schemes in terms of accuracy and computation time. © 2004 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2005 相似文献
6.
Identification of the impedance model of an implanted cochlear prosthesis from intracochlear potential measurements 总被引:2,自引:0,他引:2
Vanpoucke FJ Zarowski AJ Peeters SA 《IEEE transactions on bio-medical engineering》2004,51(12):2174-2183
Those suffering from a severe to profound sensorineural hearing loss can obtain substantial benefit from a cochlear implant prosthesis. An electrode array implanted in the inner ear stimulates auditory nerve fibers by direct injection of electrical current. A major limitation of today's technology is the imprecise control of intracochlear current flow, particularly the relatively wide spread of neural excitation. A better understanding of the intracochlear electrical fields is, therefore, required. This paper analyzes the structure of intracochlear potential measurements in relation to both the subject's anatomy and to the properties of the electrode array. An electrically equivalent network is proposed, composed of small lumped circuits for the interface impedance and for the cochlear tissues. The numerical methods required to estimate the model parameters from high-quality electrical potential recordings are developed. Finally, some models are presented for subjects wearing a Clarion CII device with a HiFocus electrode and discussed in terms of model reliability. 相似文献
7.
Basic Physicochemical Properties of Polyethylene Glycol Coated Gold Nanoparticles that Determine Their Interaction with Cells 下载免费PDF全文
Dr. Pablo del Pino Fang Yang Dr. Beatriz Pelaz Dr. Qian Zhang Karsten Kantner Raimo Hartmann Dr. Natalia Martinez de Baroja Marta Gallego Marco Möller Dr. Bella B. Manshian Dr. Stefaan J. Soenen René Riedel Prof. Dr. Norbert Hampp Prof. Dr. Wolfgang J. Parak 《Angewandte Chemie (International ed. in English)》2016,55(18):5483-5487
A homologous nanoparticle library was synthesized in which gold nanoparticles were coated with polyethylene glycol, whereby the diameter of the gold cores, as well as the thickness of the shell of polyethylene glycol, was varied. Basic physicochemical parameters of this two‐dimensional nanoparticle library, such as size, ζ‐potential, hydrophilicity, elasticity, and catalytic activity ,were determined. Cell uptake of selected nanoparticles with equal size yet varying thickness of the polymer shell and their effect on basic structural and functional cell parameters was determined. Data indicates that thinner, more hydrophilic coatings, combined with the partial functionalization with quaternary ammonium cations, result in a more efficient uptake, which relates to significant effects on structural and functional cell parameters. 相似文献
8.
In this work a novel graphical method is applied to the presentation of intercomparison results. This is demonstrated with
the results of a recent intercomparison in measuring the 137Cs, 40K, and 90Sr activity concentration in milk powder. The “PomPlot”, an intuitive graphical method, is used for producing a summary overview
of the participants’ results of a common measurand. The “PomPlot” displays (relative) deviations of individual results from
the reference value on the horizontal axis and (relative) uncertainties on the vertical axis. 相似文献
9.
This paper recalls the formalism of H. J. Leisi, which shows an alternative way to understand Perturbed Angular Correlation
Spectroscopy: as a quantum interference effect.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
10.
Barbara Geusens Mireille Van Gele Sien Braat Stefaan C. De Smedt Marc C. A. Stuart Tarl W. Prow Washington Sanchez Michael S. Roberts Niek N. Sanders Jo Lambert 《Advanced functional materials》2010,20(23):4077-4090
The extent to which nanoscale‐engineered systems cross intact human skin and can exert pharmacological effects in viable epidermis is controversial. This research seeks to develop a new lipid‐based nanosome that enables the effective delivery of siRNA into human skin. The major finding is that an ultraflexible siRNA‐containing nanosome—prepared using DOTAP, cholesterol, sodium cholate, and 30% ethanol—penetrates into the epidermis of freshly excised intact human skin and is able to enter into the keratinocytes. The nanosomes, called surfactant‐ethanol‐cholesterol‐osomes (SECosomes), show excellent size, surface charge, morphology, deformability, transfection efficiency, stability, and skin penetration capacity after complexation with siRNA. Importantly, these nanosomes have ideal characteristics for siRNA encapsulation, in that the siRNA is stable for at least 4 weeks, they enable highly efficient transfection of in vitro cultured cells, and are shown to transport siRNA delivery through intact human skin where changes in the keratinocyte cell state are demonstrated. It is concluded that increasing flexibility in nanosomes greatly enhances their ability to cross the intact human epidermal membrane and to unload their payload into targeted epidermal cells. 相似文献