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41.
42.
Depalo Nicoletta Iacobazzi Rosa Maria Valente Gianpiero Arduino Ilaria Villa Silvia Canepa Fabio Laquintana Valentino Fanizza Elisabetta Striccoli Marinella Cutrignelli Annalisa Lopedota Angela Porcelli Letizia Azzariti Amalia Franco Massimo Curri Maria Lucia Denora Nunzio 《Nano Research》2017,10(7):2431-2448
Currently,sorafenib is the only systemic therapy capable of increasing overall survival of hepatocellular carcinoma patients.Unfortunately,its side effects,particularly its overall toxicity,limit the therapeutic response that can be achieved.Superparamagnetic iron oxide nanoparticles (SPIONs) are very attractive for drug delivery because they can be targeted to specific sites in the body through application of a magnetic field,thus improving intratumoral accumulation and reducing adverse effects.Here,nanoformulations based on polyethylene glycol modified phospholipid micelles,loaded with both SPIONs and sorafenib,were successfully prepared and thoroughly investigated by complementary techniques.This nanovector system provided effective drug delivery,had an average hydrodynamic diameter of about 125 nm,had good stability in aqueous medium,and allowed controlled drug loading.Magnetic analysis allowed accurate determination of the amount of SPIONs embedded in each micelle.An in vitro system was designed to test whether the SPION micelles can be efficiently held using a magnetic field under typical flow conditions found in the human liver.Human hepatocellular carcinoma (HepG2) cells were selected as an in vitro system to evaluate tumor cell targeting efficacy of the superparamagnetic micelles loaded with sorafenib.These experiments demonstrated that this delivery platform is able to enhance sorafenib's antitumor effectiveness by magnetic targeting.The magnetic nanovectors described here represent promising candidates for targeting specific hepatic tumor sites,where selective release of sorafenib can improve its efficacy and safety profile. 相似文献
43.
Gemma M. Paech Sarah M. Jay Nicole Lamond Gregory D. Roach Sally A. Ferguson 《Applied ergonomics》2010,41(4):600-606
Shiftwork involving early morning starts and night work can affect both sleep and fatigue. This study aimed to assess the impact of different rostering schedules at an Australian mine site on sleep and subjective sleep quality. Participants worked one of four rosters;
- 4 × 4 (n = 14) 4D4O4N4O
- 7 × 4 (n = 10) 7D4O7N40
- 10 × 5 (n = 17) 5D5N50
- 14 × 7 (n = 12) 7D7N70
44.
In this paper the Tensorial-expanded Chaos Collocation method has been used to solve Fluid Dynamic problems with geometric uncertainties. The main advantage of the Tensorial-expanded Chaos Collocation method is its non-intrusive formulation, so existing deterministic solvers can be used. A Least-Squares Spectral Element Method has been employed for the analysis of the deterministic differential problems obtained by Tensorial-expanded Chaos Collocation. This algorithm exploits a Fictitious Domain approach, so it is particularly suitable to solve differential problems defined on stochastic domains. The great capabilities of the Tensorial-expanded Chaos Collocation method combined to the Fictitious Domain-Least-Squares Spectral Element Method are demonstrated by numerical experiments. 相似文献
45.
Hardware can play a significant role in improving reliability of multithreaded software. Recent architectural proposals arbitrarily group consecutive dynamic memory operations into atomic blocks to enforce coarse-grained memory ordering, providing implicit atomicity. The authors of this article observe that implicit atomicity probabilistically hides atomicity violations by reducing the number of interleaving opportunities between memory operations. They propose Atom-Aid, which creates implicit atomic blocks intelligently instead of arbitrarily, dramatically reducing the probability that atomicity violations will manifest themselves. 相似文献
46.
Photographic supra-projection is a forensic process that aims to identify a missing person from a photograph and a skull found. One of the crucial tasks throughout all this process is the craniofacial superimposition which tries to find a good fit between a 3D model of the skull and the 2D photo of the face. This photographic supra-projection stage is usually carried out manually by forensic anthropologists. It is thus very time consuming and presents several difficulties. In this paper, we aim to demonstrate that real-coded evolutionary algorithms are suitable approaches to tackle craniofacial superimposition. To do so, we first formulate this complex task in forensic identification as a numerical optimization problem. Then, we adapt three different evolutionary algorithms to solve it: two variants of a real-coded genetic algorithm and the state of the art evolution strategy CMA-ES. We also consider an existing binary-coded genetic algorithm as a baseline. Results on several superimposition problems of real-world identification cases solved by the Physical Anthropology lab at the University of Granada (Spain) are considered to test our proposals. 相似文献
47.
48.
?ukasiewicz presented two different analyses of modal notions by means of many-valued logics: (1) the linearly ordered systems ?3,..., Open image in new window ,..., \(\hbox {L}_{\omega }\); (2) the 4-valued logic ? he defined in the last years of his career. Unfortunately, all these systems contain “?ukasiewicz type (modal) paradoxes”. On the other hand, Brady’s 4-valued logic BN4 is the basic 4-valued bilattice logic. The aim of this paper is to show that BN4 can be strengthened with modal operators following ?ukasiewicz’s strategy for defining truth-functional modal logics. The systems we define lack “?ukasiewicz type paradoxes”. Following Brady, we endow them with Belnap–Dunn type bivalent semantics. 相似文献
49.
Command governor for constrained switched systems with scheduled model transition dwell times
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In this paper, a switched control architecture for constrained control systems is presented. The strategy is based on command governor ideas that are here specialized to ‘optimally’ schedule switching events on the plant dynamics for improving control performance at the expense of low computational burdens. The significance of the method mainly lies in its capability to avoid constraints violation and loss of stability regardless of any configuration change occurrence in the plant/constraint structure. To this end, the concept of model transition dwell time is used within the proposed control framework to formally define the minimum time necessary to enable a switching event under guaranteed conditions on the overall stability and constraint fulfilment. Simulation results on a simple linear system and on a Cessna 182 aircraft model show the effectiveness of the proposed strategy. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
50.
José Maurício S. Bento Terezinha M. C. Della Lucia Rosa T. S. Frighetto 《Journal of chemical ecology》1993,19(10):2347-2351
Males of the sugarcane borer,Migdolus fryanus (Coleoptera: Cerambycidae), are attracted to females by means of a sex pheromone. Mating usually occurs during a few days from October to March under field conditions in São Paulo State, Brazil. This work reports on mating of this species as affected by daily climatic factors, during a single nuptial flight. Maximum male capture by the natural sex pheromone occurred from 1000 to 1100 AM at air and soil temperatures of 30.0°C and relative humidity of 57.0%. As these temperatures increased, females burrowed into the soil, as they are more sensitive to heat than males. Thus, it was concluded that sex pheromone-mediated mating in this cerambycid is directly affected by temperatures of air and soil. 相似文献