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51.
Evaluation of gamma rays influence on some biochemical and microbiological aspects in black truffles
Filomena Nazzaro Florinda Fratianni Gianluca Picariello Raffaele Coppola Anna Reale Aldo Di Luccia 《Food chemistry》2007,103(2):344-354
The effects of two gamma-ray doses (1.5 kGy and 2.0 kGy) on some biochemical aspects and on the microbiological profile of black truffles was monitored, immediately after treatment and after 30 days of storage at 4 °C. Electrophoretic and chromatographic analyses of proteins and peptides, just like monitoring of polyphenol content, peroxides formation and microbial profile, allowed for the first time a better understanding of the mechanisms responsible for biochemical alterations and bacterial pattern in black truffles during their storage. Treatment at 1.5 kGy appeared to better preserve the characteristics of the fresh product. In 2.0 kGy-samples, the protein profile was characterised by a 20 kDa-polypeptide, which could be considered as an useful marker of the irradiation treatment and of the storage time of the product. MALDI-TOF mass spectrometry analysis did not permit a correct identification from tryptic peptides in databases, although the nano-ES/MS/MS analyses performed on the 10 kDa tryptic digest peptides showed an amino acidic sequence entirely contained in a protein of filamentous fungus Neurospora crassa. 相似文献
52.
Gianluca Quarta Karim Butalag Marisa D’Elia Marisa Tinelli 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2008,266(10):2343-2347
AMS (accelerator mass spectrometry) radiocarbon dated human bone samples recovered in the deserted medieval village of Quattro Macine, Lecce, in Southern Italy, were analyzed by PIXE (particle induced X-ray emission) and PIGE (particle induced gamma ray emission). The optimization of the PIXE-PIGE experimental set-up in term of beam energy and detection geometry resulted in the possibility to obtain information about major, minor and trace elements of the samples. Unexpectedly, all the analyzed samples showed a Pb concentration higher than 50 ppm. Two possible explanations of the measured high Pb concentration are discussed in the paper: the pre-mortem intake associated with the use of Pb-rich glazed pottery and the post-mortem intake from soil as the result of diagenetic processes. 相似文献
53.
Bernardeschi Cinzia Dini Gianluca Palmieri Maurizio Racciatti Francesco 《Journal in Computer Virology》2021,17(3):249-263
Journal of Computer Virology and Hacking Techniques - When designing Wireless Sensor Networks it is important to analyze their security risks and provide adequate solutions for protecting them from... 相似文献
54.
Maria Letizia Corradini Gianluca Ippoliti Giuseppe Orlando 《Asian journal of control》2023,25(5):3384-3394
In this paper, the control of a variable-speed variable-pitch wind turbine in the whole wind speed range is addressed, without any feedback measurement of wind speed. In addition to an aerodynamic torque observer able to ensure the tracking of the maximum delivered power in the partial-load region, a novel wind speed observer is proposed for power regulation in the full-load region, along with a sliding surface ensuring finite-time set-point stabilization of the speed tracking error. The proposed control solution has been validated on the National Renewable Energy Laboratory 5-MW three-blade wind turbine model using the recognized high-fidelity simulation tool FAST. 相似文献
55.
Bocciarelli Massimiliano Ranzi Gianluca 《Structural and Multidisciplinary Optimization》2020,61(1):91-110
Structural and Multidisciplinary Optimization - Hygro-thermo-chemical-mechanical models, used to determine the variations over time of temperature, relative humidity and shrinkage induced... 相似文献
56.
A new predictor–corrector approach for the numerical integration of coupled electromechanical equations 下载免费PDF全文
E. Tripodi A. Musolino R. Rizzo M. Raugi 《International journal for numerical methods in engineering》2016,105(4):261-285
In this paper, a new approach for the numerical solution of coupled electromechanical problems is presented. The structure of the considered problem consists of the low‐frequency integral formulation of the Maxwell equations coupled with Newton–Euler rigid‐body dynamic equations. Two different integration schemes based on the predictor–corrector approach are presented and discussed. In the first method, the electrical equation is integrated with an implicit single‐step time marching algorithm, while the mechanical dynamics is studied by a predictor–corrector scheme. The predictor uses the forward Euler method, while the corrector is based on the trapezoidal rule. The second method is based on the use of two interleaved predictor–corrector schemes: one for the electrical equations and the other for the mechanical ones. Both the presented methods have been validated by comparison with experimental data (when available) and with results obtained by other numerical formulations; in problems characterized by low speeds, both schemes produce accurate results, with similar computation times. When high speeds are involved, the first scheme needs shorter time steps (i.e., longer computation times) in order to achieve the same accuracy of the second one. A brief discussion on extending the algorithm for simulating deformable bodies is also presented. An example of application to a two‐degree‐of‐freedom levitating device based on permanent magnets is finally reported. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
57.
Multiharmonic ac-magnetic susceptibility χ1, χ2, χ3, of neutron irradiated Li-doped YBa2Cu3O7−
x
has revealed a nonmonotonic dependence of all harmonics on the neutron fluence. The irradiation has a strongly depressive
influence on the intergrain connection suggesting an increase of the effective thickness of the intergranular Josephson junction
at a neutron fluence of 0.98 × 1017 cm−2. Less damaged are the intragrain properties. A spectacular enhancement of the superconducting intragranular properties reflected
in the characteristics of all harmonics was observed at highest fluence Φ = 9.98 × 1017 cm−2. We assume that this effect results from the development of a space inhomogeneous distribution with alternating defectless
and defect-rich regions. 相似文献
58.
Buccafurri Francesco De Meo Pasquale Lax Gianluca Ursino Domenico Fugini Mariagrazia Modafferi Stefano Pernici Barbara Furnari Roberto Goy Anna Lops Pasquale Redavid Domenico Semeraro Giovanni 《Multimedia, IEEE》2009,16(1):26-35
An integrated approach to quality of service for content delivery using Web services includes quality definitions, user contracts, and fault monitoring. 相似文献
59.
D Maione E Di Carlo W Li P Musiani A Modesti M Peters S Rose-John C Della Rocca M Tripodi D Lazzaro R Taub R Savino G Ciliberto 《Canadian Metallurgical Quarterly》1998,17(19):5588-5597
Studies with tumor necrosis factor p55 receptor- and interleukin-6 (IL-6)-deficient mice have shown that IL-6 is required for hepatocyte proliferation and reconstitution of the liver mass after partial hepatectomy. The biological activities of IL-6 are potentiated when this cytokine binds soluble forms of its specific receptor subunit (sIL-6R) and the resulting complex interacts with the transmembrane signaling chain gp130. We show here that double transgenic mice expressing high levels of both human IL-6 and sIL-6R under the control of liver-specific promoters spontaneously develop nodules of hepatocellular hyperplasia around periportal spaces and present signs of sustained hepatocyte proliferation. The resulting picture is identical to that of human nodular regenerative hyperplasia, a condition frequently associated with immunological and myeloproliferative disorders. In high expressors, hyperplastic lesions progress with time into discrete liver adenomas. These data strongly suggest that the IL-6/sIL-6R complex is both a primary stimulus to hepatocyte proliferation and a pathogenic factor of hepatocellular transformation. 相似文献
60.
Gianluca Ottolina Francesca Gianinetti Sergio Riva Giacomo Carrea 《Catalysis Today》1994,22(3):511-516
The kinetic parameters (Km and Vmax) of lipoprotein lipase (LPL)-catalyzed transesterification were determined in (R)- and (S)-carvone, and in mixtures of the two. It was found that only Vmax was significantly affected by solvent chirality. LPL thermostability was not influenced by solvent config- uration, whereas activation energy was twice as high in (R)-carvone as in (S)-carvone. 相似文献