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1.
Matteo Di Giosia Alice Soldà Markus Seeger Andrea Cantelli Fabio Arnesano Maria I. Nardella Vincenzo Mangini Francesco Valle Marco Montalti Francesco Zerbetto Stefania Rapino Matteo Calvaresi Vasilis Ntziachristos 《Advanced functional materials》2021,31(20):2101527
Fullerenes are candidates for theranostic applications because of their high photodynamic activity and intrinsic multimodal imaging contrast. However, fullerenes suffer from low solubility in aqueous media, poor biocompatibility, cell toxicity, and a tendency to aggregate. C70@lysozyme is introduced herein as a novel bioconjugate that is harmless to a cellular environment, yet is also photoactive and has excellent optical and optoacoustic contrast for tracking cellular uptake and intracellular localization. The formation, water-solubility, photoactivity, and unperturbed structure of C70@lysozyme are confirmed using UV-visible and 2D 1H, 15N NMR spectroscopy. The excellent imaging contrast of C70@lysozyme in optoacoustic and third harmonic generation microscopy is exploited to monitor its uptake in HeLa cells and lysosomal trafficking. Last, the photoactivity of C70@lysozyme and its ability to initiate cell death by means of singlet oxygen (1O2) production upon exposure to low levels of white light irradiation is demonstrated. This study introduces C70@lysozyme and other fullerene-protein conjugates as potential candidates for theranostic applications. 相似文献
2.
The TSIMMIS Approach to Mediation: Data Models and Languages 总被引:18,自引:2,他引:16
Hector Garcia-Molina Yannis Papakonstantinou Dallan Quass Anand Rajaraman Yehoshua Sagiv Jeffrey Ullman Vasilis Vassalos Jennifer Widom 《Journal of Intelligent Information Systems》1997,8(2):117-132
TSIMMIS—The Stanford-IBM Manager of Multiple InformationSources—is a system for integrating information. It offers a datamodel and a common query language that are designed to support thecombining of information from many different sources. It also offerstools for generating automatically the components that are needed tobuild systems for integrating information. In this paper we shalldiscuss the principal architectural features and their rationale. 相似文献
3.
M. Kadja J.S. Anagnostopoulos G.C. Bergeles 《International Communications in Heat and Mass Transfer》1996,23(8):1065-1076
The paper presents a three-dimensional transient numerical model for atmospheric wind flow and industry and/or traffic pollutant dispersion over terrains having a complex topography. The model is based on a finite-volume integration of the equations governing mass, momentum, heat and pollutant transport within the earth's atmospheric boundary layer, using a collocated grid arrangement. The instability provoked by such a formulation was avoided by using a special pressure-velocity coupling. Local refinement of the grid was achieved via a domain decomposition method. The technique of “porosity” used to approximate curved three-dimensional boundaries is incorporated in the procedure thus avoiding the less accurate and more common approximation by a broken surface with segments parallel to the coordinate lines. The method was validated by simulating the flow over the Attica peninsula for which measurements of wind speed and pollutant emissions are available. 相似文献
4.
K. A. Anagnostopoulos S. Mavratzas A. Charalambopoulos D. I. Fotiadis 《Acta Mechanica》2003,161(1-2):39-52
Summary. We consider the acoustic scattering of time-harmonic spherical waves from an eccentric non coaxial spheroidal structure simulating
the kidney-stone system. The proposed analysis is based on the application of the translational addition theorem for spheroidal
wave functions. The resulting theoretical model is frequency-independent. Numerical results concerning the applicability of
our approach are also presented.
Received September 20, 2002 Published online: March 20, 2003 相似文献
5.
6.
We study on the forwarding of quality contextual information in mobile sensor networks (MSNs). Mobile nodes form ad-hoc distributed processing networks that produce accessible and quality-stamped information about the surrounding environment. Due to the dynamic network topology of such networks the context quality indicators seen by the nodes vary over time. A node delays the context forwarding decision until context of better quality is attained. Moreover, nodes have limited resources, thus, they have to balance between energy conservation and quality of context. We propose a time-optimized, distributed decision making model for forwarding context in a MSN based on the theory of optimal stopping. We compare our findings with certain context forwarding schemes found in the literature and pinpoint the advantages of the proposed model. 相似文献
7.
Christos L. Chochos Giannis K. Govaris Fotini Kakali Joannis K. Kallitsis Vasilis G. Gregoriou 《Polymer》2005,46(13):4654-4663
New copoly(arylether)s containing substituted terphenyl, quinquephenyl, fluorene and anthracene moieties with aromatic 1,3,4-oxadiazole units were prepared and the resulting copolymers are soluble in common organic solvents. Investigation of their optical properties revealed that they emit blue and yellow light. Moreover, their photovoltaic response was studied in blends with poly(3-hexylthiophene) (P3HT) as the electron donor. Despite the low power conversion efficiencies it was shown that photo-induced electron transfer does take place and the performances are higher than a single layer P3HT device. In addition, an anthracene-fluorene-oxadiazole main chain copolymer (PAFOXD) was also examined in a single layer photovoltaic device and gave one of the highest reported open-circuit voltage (Voc) values in the literature (0.89 V). Finally, a detailed morphological study of the blends and the PAFOXD surface using the atomic force microscopy (AFM) technique, revealed the effect of solvent selection to the preparation of thin films exhibiting the desired performance characteristics. 相似文献
8.
Routis Ioannis Bardaki Cleopatra Dede Georgia Nikolaidou Mara Kamalakis Thomas Anagnostopoulos Dimosthenis 《Software and Systems Modeling》2021,20(6):2089-2109
Software and Systems Modeling - Case Management Model and Notation (CMMN) has been introduced as a graphical modeling language targeting the modeling of human-centric processes. Despite its growing... 相似文献
9.
Marios Anagnostopoulos Georgios Kambourakis Stefanos Gritzalis 《International Journal of Information Security》2016,15(5):455-473
It is without a doubt that botnets pose a growing threat to the Internet, with DDoS attacks of any kind carried out by botnets to be on the rise. Nowadays, botmasters rely on advanced Command and Control (C&C) infrastructures to achieve their goals and most importantly to remain undetected. This work introduces two novel botnet architectures that consist only of mobile devices and evaluates both their impact in terms of DNS amplification and TCP flooding attacks, and their cost pertaining to the maintenance of the C&C channel. The first one puts forward the idea of using a continually changing mobile HTTP proxy in front of the botherder, while the other capitalizes on DNS protocol as a covert channel for coordinating the botnet. That is, for the latter, the messages exchanged among the bots and the herder appear as legitimate DNS transactions. Also, a third architecture is described and assessed, which is basically an optimized variation of the first one. Namely, it utilizes a mixed layout where all the attacking bots are mobile, but the proxy machines are typical PCs not involved in the actual attack. For the DNS amplification attack, which is by nature more powerful, we report an amplification factor that fluctuates between 32.7 and 34.1. Also, regarding the imposed C&C cost, we assert that it is minimal (about 0.25 Mbps) per bot in the worst case happening momentarily when the bot learns about the parameters of the attack. 相似文献
10.
In this paper, a two-unit multistate repairable production system is considered in which preventive maintenance (PM) is implemented in order to improve its dependability and performance. A general model is provided for the production system using a semi-Markov process, for examining system’s limiting behaviour. Apart from combining redundancy with PM, we introduce scenarios like imperfect and failed maintenance which are usually met in real life production systems. For the proposed model, we calculate the availability, the mean time to failure and the total operational cost and we formulate optimisation problems settled with respect to the system’s inspection times. The main aim of our work is to determine the optimal inspection times and consequently the optimal PM policies to be adopted in order to optimise system’s dependability and performance. 相似文献