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排序方式: 共有943条查询结果,搜索用时 15 毫秒
931.
932.
Ioana Porosnicu Cristian M. Butnaru Ion Tiseanu Elena Stancu Cristian V. A. Munteanu Bogdan I. Bita Octavian G. Duliu Felix Sima 《Molecules (Basel, Switzerland)》2021,26(11)
The innovative strategy of using nanoparticles in radiotherapy has become an exciting topic due to the possibility of simultaneously improving local efficiency of radiation in tumors and real-time monitoring of the delivered doses. Yttrium oxide (Y2O3) nanoparticles (NPs) are used in material science to prepare phosphors for various applications including X-ray induced photodynamic therapy and in situ nano-dosimetry, but few available reports only addressed the effect induced in cells by combined exposure to different doses of superficial X-ray radiation and nanoparticles. Herein, we analyzed changes induced in melanoma cells by exposure to different doses of X-ray radiation and various concentrations of Y2O3 NPs. By evaluation of cell mitochondrial activity and production of intracellular reactive oxygen species (ROS), we estimated that 2, 4, and 6 Gy X-ray radiation doses are visibly altering the cells by inducing ROS production with increasing the dose while at 6 Gy the mitochondrial activity is also affected. Separately, high-concentrated solutions of 25, 50, and 100 µg/mL Y2O3 NPs were also found to affect the cells by inducing ROS production with the increase of concentration. Additionally, the colony-forming units assay evidenced a rather synergic effect of NPs and radiation. By adding the NPs to cells before irradiation, a decrease of the number of proliferating cell colonies was observed with increase of X-ray dose. DNA damage was evidenced by quantifying the γ-H2AX foci for cells treated with Y2O3 NPs and exposed to superficial X-ray radiation. Proteomic profile confirmed that a combined effect of 50 µg/mL Y2O3 NPs and 6 Gy X-ray dose induced mitochondria alterations and DNA changes in melanoma cells. 相似文献
933.
We complete the classification of Hopf algebras of dimension 16 over an algebraically closed field of characteristic zero.
We show that a non-semisimple Hopf algebra of dimension 16, has either the Chevalley property or its dual is pointed. 相似文献
934.
The first example of a recursive function which is not primitive recursive is usually attributed to W. Ackermann. The authors of the present paper show that such an example can also be found in a paper by G. Sudan, published concomitantly with Ackermann's paper. 相似文献
935.
936.
In this paper, we firstly extend some classical operators on Sasakian manifolds acting to 1-differentiable forms on Sasakian manifolds. Next in a similar manner with the study of C-harmonic forms, we define and extend such a study for the case of 1-differentiable forms on Sasakian manifolds. 相似文献
937.
Hanife Apaydin-Özkan Jorge Júlvez Cristian Mahulea Manuel Silva 《Nonlinear Analysis: Hybrid Systems》2011,5(2):136-148
This paper considers the problem of controlling timed continuous Petri nets under infinite server semantics. The proposed control strategy assigns piecewise constant flows to transitions in order to reach the target state. First, by using linear programming, a method driving the system from the initial to the target state through a linear trajectory is developed. Then, in order to improve the time of the trajectory, intermediate states are added by means of bilinear programming. Finally, in order to handle potential perturbations, we develop a closed loop control strategy that follows the trajectory computed by the open loop control by calculating a new state after each time step. The algorithms developed here are applied to a manufacturing system. 相似文献
938.
Cristian D. González-Avilés 《Central European Journal of Mathematics》2013,11(7):1159-1176
We generalize Colliot-Thélène’s construction of flasque resolutions of reductive group schemes over a field to a broad class of base schemes. 相似文献
939.
Cristian Valenzuela Yuanhao Chen Prof. Ling Wang Prof. Wei Feng 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(70):e202201957
The marriage of liquid crystal elastomers with dynamic covalent chemistry can be a new paradigm for the development of dynamic and intelligent polymers with versatile functionalities, which is of paramount significance for many emerging applications such as adaptive optics, soft robotics, bioinspired camouflage, 3D/4D printing technology and beyond. Read more in the Review by Wang, Feng et al. ( 10.1002/chem.202201957 ) 相似文献
940.
Lorenzo Lombardi Alessandro Kovtun Sebastiano Mantovani Dr. Giulio Bertuzzi Laura Favaretto Cristian Bettini Dr. Vincenzo Palermo Dr. Manuela Melucci Prof. Marco Bandini 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(26):e202200333
We present an environmentally benign methodology for the covalent functionalization (arylation) of reduced graphene oxide (rGO) nanosheets with arylazo sulfones. A variety of tagged aryl units were conveniently accommodated at the rGO surface via visible-light irradiation of suspensions of carbon nanostructured materials in aqueous media. Mild reaction conditions, absence of photosensitizers, functional group tolerance and high atomic fractions (XPS analysis) represent some of the salient features characterizing the present methodology. Control experiments for the mechanistic elucidation (Raman analysis) and chemical nanomanipulation of the tagged rGO surfaces are also reported. 相似文献