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961.
962.
Francesco Brioschi 《Mathematische Annalen》1887,29(3):327-330
Ohne Zusammenfassung 相似文献
963.
964.
Dr. Giulia Neri Dr. Giuliana Mion Dr. Andrea Pizzi Dr. Wanda Celentano Dr. Linda Chaabane Prof. Michele R. Chierotti Prof. Roberto Gobetto Dr. Min Li Prof. Piergiorgio Messa Dr. Floryan De Campo Prof. Francesco Cellesi Prof. Pierangelo Metrangolo Prof. Francesca Baldelli Bombelli 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(44):10057-10063
In the continuous search for multimodal systems with combined diagnostic and therapeutic functions, several efforts have been made to develop multifunctional drug delivery systems. In this work, through a covalent approach, a new class of fluorinated poly(lactic-co-glycolic acid) co-polymers (F-PLGA) were designed that contain an increasing number of magnetically equivalent fluorine atoms. In particular, two novel compounds, F3-PLGA and F9-PLGA, were synthesized and their chemical structure and thermal stability were analyzed by solution NMR, DSC, and TGA. The obtained F-PLGA compounds were proven to form in aqueous solution colloidal stable nanoparticles (NPs) displaying a strong 19F NMR signal. The fluorinated NPs also showed an enhanced ability to load hydrophobic drugs containing fluorine atoms compared to analogous pristine PLGA NPs. Preliminary in vitro studies showed high cell viability and the NP ability to intracellularly deliver and release a functioning drug. 相似文献
965.
Vincenzo Campisciano Carla Calabrese Leonarda Francesca Liotta Valeria La Parola Alberto Spinella Carmela Aprile Michelangelo Gruttadauria Francesco Giacalone 《应用有机金属化学》2019,33(7)
Two different carbon nanoforms (CNFs), namely multi‐walled carbon nanotubes (MWCNTs) and carbon nanohorns (CNHs), have been chosen as support for the direct polymerization of a bis‐vinylimidazolium salt. Transmission electron microscopy analyses revealed a templating effect of the CNFs on the growth of the polymeric network, which perfectly covers their whole surfaces creating a cylindrical or spherical coating for MWCNTs and CNHs, respectively. Subsequently, the CNFs‐polyimidazolium have been used as stabilizers for Pd nanoparticles (Pd NPs), and the obtained materials have been characterized by means of analytical and spectroscopic techniques and then employed as easily recoverable and recyclable catalysts for Suzuki and Heck reactions. Quantitative conversions have been obtained in almost all the explored reactions, even employing low loading of catalyst (down to 0.007 mol%). Suzuki reactions were carried out in pure water under aerobic conditions. Both materials showed excellent activity and recyclability for the investigated C‐C coupling reactions, with the CNHs‐based material resulting slightly more active than the MWCNTs‐based one due to a higher superficial exposure of Pd NPs. 相似文献
966.
Marco Di Francesco Simone Fagioli Emanuela Radici 《Journal of Differential Equations》2019,266(5):2830-2868
We construct a deterministic, Lagrangian many-particle approximation to a class of nonlocal transport PDEs with nonlinear mobility arising in many contexts in biology and social sciences. The approximating particle system is a nonlocal version of the follow-the-leader scheme. We rigorously prove that a suitable discrete piece-wise density reconstructed from the particle scheme converges strongly in towards the unique entropy solution to the target PDE as the number of particles tends to infinity. The proof is based on uniform BV estimates on the approximating sequence and on the verification of an approximated version of the entropy condition for large number of particles. As part of the proof, we also prove uniqueness of entropy solutions. We further provide a specific example of non-uniqueness of weak solutions and discuss the interplay of the entropy condition with the steady states. Finally, we produce numerical simulations supporting the need of a concept of entropy solution in order to get a well-posed semigroup in the continuum limit, and showing the behaviour of solutions for large times. 相似文献
967.
De Gregorio Alessandro Iafrate Francesco 《Annals of the Institute of Statistical Mathematics》2021,73(5):921-951
Annals of the Institute of Statistical Mathematics - The aim of this paper is to introduce an adaptive penalized estimator for identifying the true reduced parametric model under the sparsity... 相似文献
968.
Potential Analysis - We focus on a class of path-dependent problems which include path-dependent PDEs and Integro PDEs (in short IPDEs), and their representation via BSDEs driven by a cadlag... 相似文献
969.
Landslides falling into water bodies can generate destructive waves, which can be classified as tsunamis. An experimental facility to study this phenomenon has been set up. It consists of a landslide generator releasing gravel at high-speed into a wave basin. A non-intrusive system has been designed ad-hoc to be able to measure the high velocity and the geometry of the landslide as well as the generated waves characteristics. The measurement system employs the treatment of images captured by a high-speed camera which records the launched granular material illuminated by a laser sheet. A grid of laser sheets marks the basin water surface. The water has been filled by a small amount of kaolin to properly reflect the laser light at water surface. Thus, by filming with high definition cameras the perturbed water surface and successively processing the resulting images, it has been possible to measure the generated waves. The measurement framework employs a versatile camera calibration technique which allows accurate measurements in presence of: (1) high lens distortions; (2) pronounced non-parallelism condition between camera sensor and plane of measurement coincident with the laser sheet. The maximum resolution of the measurement tool is 0.01 mm, while the maximum uncertainty due to systematic error has been estimated to be 15% for the worst-case scenario. This work improves the suitability of image-based measuring systems in granular flows and free surface hydraulics experiments. 相似文献
970.
Andrew J. Carrod Francesco Graglia Dr. Louise Male Dr. Cécile Le Duff Peter Simpson Dr. Mohamed Elsherif Dr. Zubair Ahmed Dr. Haider Butt Guang-Xi Xu Prof. Kenneth Kam-Wing Lo Dr. Paolo Bertoncello Prof. Zoe Pikramenou 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(4):e202103541
Dual detection systems are of interest for rapid, accurate data collection in sensing systems and in vitro testing. We introduce an IrIII complex with a boronic acid receptor site attached to the 2-phenylpyridine ligand as an ideal probe with photo- and electrochemical signals that is sensitive to monosaccharide binding in aqueous solution. The complex displays orange luminescence at 618 nm, which is reduced by 70 and 40 % upon binding of fructose and glucose, respectively. The electro-chemiluminescent signal of the complex also shows a direct response to monosaccharide binding. The IrIII complex shows the same response upon incorporation into hydrogel matrices as in solution, thus demonstrating the potential of its integration into a device, as a nontoxic, simple-to-use tool to observe sugar binding over physiologically relevant pH ranges and saccharide concentrations. Moreover, the complex's luminescence is responsive to monosaccharide presence in cancer cells. 相似文献