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61.
Annalisa Allocca Giuseppe Bimonte Detlef Born Enrico Calloni Giampiero Esposito Uwe Huebner Evgeni Il’ichev Luigi Rosa Francesco Tafuri 《Journal of Superconductivity and Novel Magnetism》2012,25(8):2557-2565
The ALADIN experiment aims at observing how the critical magnetic field of a superconducting aluminum film is modified, when it constitutes one of the reflecting surfaces of a Casimir cavity. If successful, such an observation would reveal the influence of vacuum energy on the superconducting phase transition. In this paper, a rigorous analysis of experimental data is reported, the results are discussed and compared with theoretical predictions based on Lifshitz theory of dispersion forces, and the BCS formula for the optical conductivity of superconductors. Thanks to this rigorous analysis, it can now be asserted that in the region of energy where it is expected that Casimir energy is comparable with condensation energy and the deviations of critical field from BCS formula to be not negligible, an anomalous behavior is found. 相似文献
62.
Monorchio A. Manara G. Serra U. Marola G. Pagana E. 《Microwave and Wireless Components Letters, IEEE》2005,15(6):407-409
A new optimization procedure suitable for the design of waveguide filters is presented. The filter structure consists of a frequency selective surface (FSS), placed on the transverse plane of a rectangular waveguide, so introducing a filtering behavior of the waveguide. Due to the boundary conditions imposed by the metallic waveguide walls, the FSS results to be infinite in extent, allowing the use of fast and efficient method of moments solvers to analyze its properties. A genetic algorithm (GA) has been adopted to optimize the filter performance. As an application, a waveguide filter has been designed to be used in an easy to fabricate and inexpensive very small aperture terminal (VSAT) feeder, for the ground station of an interactive satellite system. 相似文献
63.
Francesco Beltrame Luisa Cotta Marilena De Ceglia Marco Fato Giampiero Marcenaro Davide Caramella Massimo Del Sarto Irwin Sobel 《Magma (New York, N.Y.)》1994,2(4):551-558
Biomedical image analysis workstations can be linked to 3D data-oriented devices for a new approach to image manipulation in biology and medicine. Stereo monitors allow an intuitive approach to medical diagnosis. The use of 3D head-tracking devices allows a more compelling 3D illusion to be generated. A stylus can be used as an electronic knife for dissecting a 3D data set; furthermore, other 3D sensors are available for tracking operator arm movements. The overall character of this work is firmly application oriented, in order to provide concrete operational tools to the medical user. Such tools range from diagnostic up to therapeutic and robotized use of bioimages. 相似文献
64.
Adaptive neural controllers are often criticised for the lack of clear and easy design methodologies that relate adaptive neural network (NN) design parameters to performance requirements. This study proposes a methodology for the design of an integrated linear-adaptive model reference controller that guarantees component-wise boundedness of the tracking error within an a priori specified compact domain. The approach is based on the design of a robust invariant ellipsoidal set where both the NN reconstruction error and the neuro-adaptive control are considered as bounded persistent uncertainties. We show that all the performance and control requirements for the closed-loop system can be expressed as linear matrix inequality constraints. This brings the advantage that feasibility and optimal design parameters can be effectively computed while solving a linear optimisation problem. An advantage of the method is that it allows a systematic and quantitative evaluation of the interplay between the design parameters and their impact on the requirements. This produces an integrated linear/neuro-adaptive performance-oriented design methodology. A numerical example is used to illustrate the approach. 相似文献
65.
66.
Mariangela Pampalone Giampiero Vitale Salvatore Gruttadauria Giandomenico Amico Gioacchin Iannolo Bruno Douradinha Alessandra Mularoni Pier Giulio Conaldi Giada Pietrosi 《International journal of molecular sciences》2022,23(2)
Background: Spontaneous bacterial peritonitis (SBP) is a severe and often fatal infection in patients with decompensated cirrhosis and ascites. The only cure for SBP is antibiotic therapy, but the emerging problem of bacterial resistance requires novel therapeutic strategies. Human amniotic mesenchymal stromal cells (hA-MSCs) possess immunomodulatory and anti-inflammatory properties that can be harnessed as a therapy in such a context. Methods: An in vitro applications of hA-MSCs in ascitic fluid (AF) of cirrhotic patients, subsequently infected with carbapenem-resistant Enterobacterales, was performed. We evaluated the effects of hA-MSCs on bacterial load, innate immunity factors, and macrophage phenotypic expression. Results: hA-MSCs added to AF significantly reduce the proliferation of both bacterial strains at 24 h and diversely affect M1 and M2 polarization, C3a complement protein, and ficolin 3 concentrations during the course of infection, in a bacterial strain-dependent fashion. Conclusion: This study shows the potential usefulness of hA-MSC in treating ascites infected with carbapenem-resistant bacteria and lays the foundation to further investigate antibacterial and anti-inflammatory roles of hA-MSC in in vivo models. 相似文献
67.
红色和黑色是具有历史意义的先锋颜色,在上个世纪它们代表着大胆不羁的意识形态和由革新方式表选的道德与文化信念所构成的艺术运动.这是那种能代表某种针对对象本质引发的潮流和张力的颜色,而白色代表用来罗列它们意义和内涵的虚无空间. 相似文献
68.
The Optical, Spectroscopic, and Infrared Remote Imaging System (OSIRIS) instrument on board the Rosetta spacecraft, a misson of the European Space Agency to comet P/Wirtanen, includes two cameras for acquiring images of the comet. A set of interference filters deposited upon glass and fused-silica substrates will be added to the cameras for wavelength tuning. For this mission of more than 10/years in an interplanetary environment, the requirement of preserving the optical characteristics of the filters is a critical one. We checked the variation in the transmission of some filter substrates after proton irradiation that simulated the solar wind. To produce a situation that is representative of the interplanetary environment, we irradiated proton fluences at three energies: 1.5 x 10(11) protons/cm2 at 4 MeV, 1.9 x 10(10) protons/cm2 at 8 MeV, and 7.1 x 10(9) protons/cm2 at 18 MeV. Seven substrates were tested: three Suprasil-1; three colored glasses, namely, OG590, KG3, and RG9; and one quartz. In addition, two interference filters were checked. The results obtained show that Suprasil-1 is rather insensitive to this irradiation, whereas very small reductions in transmission, of the order of a few percent, occur for colored glasses. The transmission of these filters was remeasured 2 years after the irradiation, and showed a general decrease in the transmission reduction. 相似文献
69.
Porretta M. Nepa P. Manara G. Giannetti F. Dohler M. Allen B. Aghvami A.H. 《Vehicular Technology, IEEE Transactions on》2004,53(5):1502-1514
Positioning algorithms in cellular networks has become increasingly important as a means of supporting emerging services that require a sufficiently precise estimation of the position of the mobile terminal (MT) associated with a given base station (BS). Currently, even the most sophisticated positioning algorithms require at least three BSs to achieve satisfactory precision. This paper presents a novel algorithm that makes use of a single-BS antenna array to locate MTs in cellular networks. A triangulation technique is utilized and supported by some minimal information about the environment in the BS neighborhood. This algorithm is shown to perform well when operating in a microcellular environment with perfect channel-parameter estimation. The effect of finite resolution of the input parameters is also investigated. The performance is analyzed for a universal mobile telecommunications system microcellular scenario through a three-dimensional deterministic channel model. Finally, the performance of the proposed positioning technique is compared to the well-known location method based on the time-of-arrival measurements at three different BSs. 相似文献
70.
Cambi Alessandra; Vincenzetti Silvia; De Sanctis Giampiero; Neuhard Jan; Natalini Paolo; Vita Alberto 《Protein engineering, design & selection : PEDS》2001,14(10):807-813
We cloned, purified and characterized two extremophilic cytidinedeaminases: CDABcald and CDABpsy, isolated from Bacillus caldolyticus(growth at 72°C) and Bacillus psychrophilus (growth at 10°C),respectively. We compared their thermostability also with themesophilic counterpart, CDABsubt, isolated from Bacillus subtilis(growth at 37°C). The DNA fragments encoding CDABcald andCDABpsy were sequenced and the deduced amino acid sequencesshowed 70% identity. High sequence similarity was also foundwith the mesophilic CDABsubt. Both enzymes were found to behomotetramers of approximately 58 kDa. CDABcald was found tobe highly thermostable, as expected, up to 65°C, whereasCDABpsy showed higher specific activity at lower temperaturesand was considerably less thermostable than CDABcald. Afterpartial denaturation at 72°C for 30 min, followed by renaturationon ice, CDABcald recovered 100% of its enzymatic activity, whereasCDABpsy as well as CDABsubt were irreversibly inactivated. Circulardichroism (CD) spectra of CDABcald and CDABpsy at temperaturesranging from 10 to 95°C showed a markedly different thermostabilityof their secondary structures: at 10 and 25°C the CD spectrawere indistinguishable, suggesting a similar overall structure,but as temperature increases up to 5070°C, the -helicesof CDABpsy unfolded almost completely, whereas its ß-structureand the aromatic amino acids core remained pretty stable. Nosignificant differences were seen in the secondary structuresof CDABcald with increase in temperature. 相似文献