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排序方式: 共有205条查询结果,搜索用时 250 毫秒
101.
A Baldi V Esposito A De Luca Y Fu I Meoli GG Giordano M Caputi F Baldi A Giordano 《Canadian Metallurgical Quarterly》1997,3(10):1691-1697
Two proteins, p107 and pRb2/p130, which are structurally and functionally similar to the product of the retinoblastoma gene (pRb), were cloned by taking advantage of their ability to bind transforming proteins of DNA tumor viruses through a particular region called the "pocket domain." Like pRb, both proteins play a fundamental role in growth control. Using immunocytochemical techniques, we examined a variety of normal human tissues for the expression of pRb2/p130 and p107. Both proteins were expressed ubiquitously, although a different tissue distribution and/or level of expression were found in various organs. Terminally differentiated cells, such as neurons and skeletal muscle, showed high expression levels for Rb2/p130, whereas p107 was expressed at higher levels in other cell types such as epithelia of the breast and prostate. We then examined the expression pattern of Rb2/p130 in 158 specimens of human lung cancer and found an inverse correlation between the histological grading of the tumors, the development of metastasis, and the level of expression of Rb2/p130. 相似文献
102.
Two hydrodynamic models of the liquid in a trickle-bed reactor: PE and PDE model, have been considered, and the influence of the identification method on the parameter values was examined. The employed identification methods were: the moments method, supplemented by graphical determinations on the response curve, and the best fit method, where the minimum absolute and relative error between the calculated and experimental response curve was adopted as identification criteria.Except the total liquid hold-up, the values of the other parameters of both models were very sensitive to the identification method especially at low liquid flow rates. For this reason, much care must be taken in comparing literature results.The experimental runs were carried out with two tracer of rather different diffusivity; no influence of this on the parameter values was observed; this would mean, in particular, that the mass transfer between dynamic and stagnant zones is attributable to the movement of fluid streams between them. 相似文献
103.
Stefania Albonetti Giovanni Baldi Andrea Barzanti Enrique Rodriguez Castellon Antonio Jimenz Lopez Dolores Eliche Quesada Angelo Vaccari 《Catalysis Letters》2006,108(3-4):197-207
Pd/Rh and Pd/Pt catalysts supported on two different mesoporous materials – a Zr-doped MCM-41-type silica [Si/Zr = 5 w/w (SiZr)]
and a commercial silica-alumina [Si/Al = 40:60 w/w (SiAl)] – were prepared by incipient wetness impregnation using nanosized
suspensions of alloy particles prepared by polyol-mediated synthesis in diethylene glycol (DEG). The catalytic behaviour of
these catalysts was investigated in the hydrogenation and hydrogenolysis/ring-opening of naphthalene at 6.0 MPa, by checking
the role of both the main reaction conditions (temperature, contact time and H2/naphthalene molar ratio) and increasing amounts of dibenzothiophene (DBT). The catalysts supported on SiAl showed higher
activity than catalysts supported on SiZr, thus suggesting that activity is favoured by higher acidity of the support and/or
higher interaction of the nanosized metal particles with the support. While using the SiZr support, weaker metal-support interactions
took place by forming catalysts with bigger metal and/or metal oxide particles. Besides, the catalyst with lowest noble-metal
content (0.3 wt.%) (SiAl-0.3Pd/Pt-5) had the greatest acidity and metal surface and, consequently, the highest activity. Furthermore,
it exhibited a good thiotolerance in presence of increasing amounts of DBT in the feed, thus maintaining a high catalytic
activity in the hydrogenation of naphthalene, although with decreased yield in trans- and cis-decalin (decahydronaphthalene or DeHN) and high-molecular-weight compounds (H.M.W.), with a corresponding increased yield
in the partially hydrogenated tetralin (tetrahydronaphthalene or TeHN). 相似文献
104.
Marco Baldi Marco Bianchi Franco Chiaraluce Joachim Rosenthal Davide Schipani 《Journal of Cryptology》2016,29(1):1-27
This paper studies a variant of the McEliece cryptosystem able to ensure that the code used as the public key is no longer permutation equivalent to the secret code. This increases the security level of the public key, thus opening the way for reconsidering the adoption of classical families of codes, like Reed–Solomon codes, that have been longly excluded from the McEliece cryptosystem for security reasons. It is well known that codes of these classes are able to yield a reduction in the key size or, equivalently, an increased level of security against information set decoding; so, these are the main advantages of the proposed solution. We also describe possible vulnerabilities and attacks related to the considered system and show what design choices are best suited to avoid them. 相似文献
105.
Alain Garrigou Isabelle Baldi Patricia Le Frious Rémy Anselm Martine Vallier 《Applied ergonomics》2011,(2):321-330
The purpose of this article is to present the contribution of a trans-disciplinary approach focused on ergonomics and chemical risk control. We shall more precisely discuss how such an approach carried out in the field of agricultural work has made it possible to highlight serious shortcomings in the effectiveness of the coveralls that are supposed to protect vineyard workers from pesticides. The study results, as well as the whistle-blow that followed have questioned the control and prevention measures used until then. The aforementioned trans-disciplinary approach gathers knowledge and methods from epidemiology, industrial hygiene, occupational health and safety and ergonomics. Ergonomics were central in the development of the approach as it connected task and activity analysis with contamination measurements. Lastly, the first results that were obtained have been confirmed and reused by the AFSSET (Agence Française de Sécurité Sanitaire Environnement et Travail, the French governmental agency in charge of environmental health and occupational health and safety issues) regarding the agricultural sector but also for all other situations in which workers use coveralls as protection against chemical risks. 相似文献
106.
Experimental Analysis of the Errors due to Polynomial Interpolation in Digital Image Correlation
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Digital image correlation attempts to estimate displacement fields by digitally correlating two images acquired before and after motion. To do so, pixel intensity has to be interpolated at non‐integer locations. The ideal interpolator is the sinc, but as it requires infinite support, it is not normally used and is replaced by polynomials. Polynomial interpolation produces visually appealing results but introduces positional errors in the signal, thus causing the digital image correlation algorithms to converge to incorrect results. In this work, an experimental campaign is described, that aims to characterise the errors introduced by interpolation, focusing in particular on the systematic error and the standard deviation of displacements. 相似文献
107.
R.R. Aspilcueta-Borquis F. Baldi L.G. Albuquerque H. Tonhati 《Journal of dairy science》2010,93(5):2195-2201
The availability of accurate genetic parameters for important economic traits in milking buffaloes is critical for implementation of a genetic evaluation program. In the present study, heritabilities and genetic correlations for fat (FY305), protein (PY305), and milk (MY305) yields, milk fat (%F) and protein (%P) percentages, and SCS were estimated using Bayesian methodology. A total of 4,907 lactations from 1,985 cows were used. The (co)variance components were estimated using multiple-trait analysis by Bayesian inference method, applying an animal model, through Gibbs sampling. The model included the fixed effects of contemporary groups (herd-year and calving season), number of milking (2 levels), and age of cow at calving as (co)variable (quadratic and linear effect). The additive genetic, permanent environmental, and residual effects were included as random effects in the model. The posterior means of heritability distributions for MY305, FY305, PY305, %F, P%, and SCS were 0.22, 0.21, 0.23, 0.33, 0.39, and 0.26, respectively. The genetic correlation estimates ranged from −0.13 (between %P and SCS) to 0.94 (between MY305 and PY305). The permanent environmental correlation estimates ranged from −0.38 (between MY305 and %P) to 0.97 (between MY305 and PY305). Residual and phenotypic correlation estimates ranged from −0.26 (between PY305 and SCS) to 0.97 (between MY305 and PY305) and from −0.26 (between MY305 and SCS) to 0.97 (between MY305 and PY305), respectively. Milk yield, milk components, and milk somatic cells counts have enough genetic variation for selection purposes. The genetic correlation estimates suggest that milk components and milk somatic cell counts would be only slightly affected if increasing milk yield were the selection goal. Selecting to increase FY305 or PY305 will also increase MY305, %P, and %F. 相似文献
108.
Miriam Petitti Andrea Nasuti Daniele L. Marchisio Marco Vanni Giancarlo Baldi Nicola Mancini Fabrizio Podenzani 《American Institute of Chemical Engineers》2010,56(1):36-53
Local gas hold‐up and bubbles size distributions have been modeled and validated against experimental data in a stirred gas–liquid reactor, considering two different spargers. An Eulerian multifluid approach coupled with a population balance model (PBM) has been employed to describe the evolution of the bubble size distribution due to break‐up and coalescence. The PBM has been solved by resorting to the quadrature method of moments, implemented through user defined functions in the commercial computational fluid dynamics code Fluent v. 6.2. To overcome divergence issues caused by moments corruption, due to numerical problems, a correction scheme for the moments has been implemented; simulation results prove that it plays a crucial role for the stability and the accuracy of the overall approach. Very good agreements between experimental data and simulations predictions are obtained, for a unique set of break‐up and coalescence kinetic constants, in a wide range of operating conditions. © 2009 American Institute of Chemical Engineers AIChE J, 2010 相似文献
109.
110.
Sabrina Nicol Michele Tanturli Giorgio Mattiuz Alberto Antonelli Ilaria Baccani Chiara Bonaiuto Simone Baldi Giulia Nannini Marta Menicatti Gianluca Bartolucci Gian Maria Rossolini Amedeo Amedei Maria Gabriella Torcia 《International journal of molecular sciences》2021,22(12)
Persistent infection with High Risk-Human Papilloma Viruses (HR-HPVs) is a primary cause of cervical cancer worldwide. Vaginal-dysbiosis-associated bacteria were correlated with the persistence of HR-HPVs infection and with increased cancer risk. We obtained strains of the most represented bacterial species in vaginal microbiota and evaluated their effects on the survival of cervical epithelial cells and immune homeostasis. The contribution of each species to supporting the antiviral response was also studied. Epithelial cell viability was affected by culture supernatants of most vaginal-dysbiosis bacteria, whereas Lactobacillus gasseri or Lactobacillus jensenii resulted in the best stimulus to induce interferon-γ (IFN-γ) production by human mononuclear cells from peripheral blood (PBMCs). Although vaginal-dysbiosis-associated bacteria induced the IFN-γ production, they were also optimal stimuli to interleukin-17 (IL-17) production. A positive correlation between IL-17 and IFN-γ secretion was observed in cultures of PBMCs with all vaginal-dysbiosis-associated bacteria suggesting that the adaptive immune response induced by these strains is not dominated by TH1 differentiation with reduced availability of IFN-γ, cytokine most effective in supporting virus clearance. Based on these results, we suggest that a vaginal microbiota dominated by lactobacilli, especially by L. gasseri or L. jensenii, may be able to assist immune cells with clearing HPV infection, bypasses the viral escape and restores immune homeostasis. 相似文献