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101.
Kieran P. Donaghy Daniela Federici Giancarlo Gandolfo 《The Annals of Regional Science》2001,35(3):449-461
Most recent theoretical research on endogenous economic growth has been conducted with continuous-time models that embody
the assumption of an intertemporally optimizing representative agent. Yet virtually none of these models has been confronted
with empirical data. In this paper we make use of a model of an open economy recently developed by Turnovsky to demonstrate
one approach to the estimation and analysis of such models. We present the results of the estimation, analyze the estimated
model's stability properties around its steady-state solution, and explore the model's behavior in response to alternative
tax policies. 相似文献
102.
Elisa Di Fabio Antonia Iazzetti Alessio Incocciati Valentina Caseli Giancarlo Fabrizi Alberto Boffi Alessandra Bonamore Alberto Macone 《International journal of molecular sciences》2022,23(12)
Amine oxidases are enzymes belonging to the class of oxidoreductases that are widespread, from bacteria to humans. The amine oxidase from Lathyrus cicera has recently appeared in the landscape of biocatalysis, showing good potential in the green synthesis of aldehydes. This enzyme catalyzes the oxidative deamination of a wide range of primary amines into the corresponding aldehydes but its use as a biocatalyst is challenging due to the possible inactivation that might occur at high product concentrations. Here, we show that the enzyme’s performance can be greatly improved by immobilization on solid supports. The best results are achieved using amino-functionalized magnetic microparticles: the immobilized enzyme retains its activity, greatly improves its thermostability (4 h at 75 °C), and can be recycled up to 8 times with a set of aromatic ethylamines. After the last reaction cycle, the overall conversion is about 90% for all tested substrates, with an aldehyde production ranging between 100 and 270 mg depending on the substrate used. As a proof concept, one of the aldehydes thus produced was successfully used for the biomimetic synthesis of a non-natural benzylisoquinoline alkaloid. 相似文献
103.
TORRI Giancarlo 《核技术(英文版)》2012,(1):19-28
A sensitive and accurate method for determining ultra low-level 210Pb and 212Pb in water samples through double measurements was developed.Pb was pre-concentrated as hydroxides,separated from alkaline earth elements as PbS precipitate,purified by an anion exchange resin chromatography column,precipitated as PbSO4 for source preparation and counted by a low background β-counter.The procedure was checked with IAEA reference materials,and the results agreed well with the recommended values.Theminimum detectable activity was 0.062 mBq·L-1 for 210Pb and 0.053 mBq·L-1 for 212Pb with a 48 L water sample.Seventeen drinking water samples were analyzed,with a Pb recovery of 88.8?5.5%,and the typical activity concentrations were 0.191?15.1 mBq·L-1 for 210Pb and of 1.12?5.77 mBq·L-1 for 212Pb.The estimated committed effective doses to adult members of the public in Italy due to intake of 210Pb and 212Pb in drinking water were 0.096?7.59 μSv·a-1 and 0.005?0.025 μSv·a-1,respectively. 相似文献
104.
Gianmaria Salvio Alessandro Ciarloni Melissa Cutini Nicola delli Muti Federica Finocchi Michele Perrone Silvia Rossi Giancarlo Balercia 《International journal of molecular sciences》2022,23(10)
Metabolic syndrome (MetS) is a highly prevalent condition among adult males, affecting up to 41% of men in Europe. It is characterized by the association of obesity, hypertension, and atherogenic dyslipidemia, which lead to premature morbidity and mortality due to cardiovascular disease (CVD). Male infertility is another common condition which accounts for about 50% of cases of couple infertility worldwide. Interestingly, male infertility and MetS shares several risk factors (e.g., smoking, ageing, physical inactivity, and excessive alcohol consumption), leading to reactive oxygen species (ROS) production and increased oxidative stress (OS), and resulting in endothelial dysfunction and altered semen quality. Thus, the present narrative review aims to discuss the pathophysiological mechanisms which link male infertility and MetS and to investigate the latest available evidence on the reproductive consequences of MetS. 相似文献
105.
From first principles to the Burrows and Wheeler transform and beyond,via combinatorial optimization
We introduce a combinatorial optimization framework that naturally induces a class of optimal word permutations with respect to a suitably defined cost function taking into account various measures of relatedness between words. The Burrows and Wheeler transform (bwt) (cf. [M. Burrows, D. Wheeler, A block sorting lossless data compression algorithm, Technical Report 124, Digital Equipment Corporation, 1994]), and its analog for labelled trees (cf. [P. Ferragina, F. Luccio, G. Manzini, S. Muthukrishnan, Structuring labeled trees for optimal succinctness, and beyond, in: Proc. of the 45th Annual IEEE Symposium on Foundations of Computer Science, 2005, pp. 198–207]), are special cases in the class. We also show that the class of optimal word permutations defined here is identical to the one identified by Ferragina et al. for compression boosting [P. Ferragina, R. Giancarlo, G. Manzini, M. Sciortino, Boosting textual compression in optimal linear time, Journal of the ACM 52 (2005) 688–713]. Therefore, they are all highly compressible. We also provide, by using techniques from Combinatorics on Words, a fast method to compute bwt without using any end-of-string symbol. We also investigate more general classes of optimal word permutations, where relatedness of symbols may be measured by functions more complex than context length. For this general problem we provide an instance that is MAX-SNP hard, and therefore unlikely to be solved or approximated efficiently. The results presented here indicate that a key feature of the Burrows and Wheeler transform seems to be, besides compressibility, the existence of efficient algorithms for its computation and inversion. 相似文献
106.
Ianni Michele Masciari Elio Sperlí Giancarlo 《Journal of Intelligent Information Systems》2021,57(1):73-100
Journal of Intelligent Information Systems - The pervasive diffusion of Social Networks (SN) produced an unprecedented amount of heterogeneous data. Thus, traditional approaches quickly became... 相似文献
107.
Giancarlo Bartolucci Mircea Dragoman Romolo Marcelli Fabrizio Pini 《Journal of Infrared, Millimeter and Terahertz Waves》1995,16(10):1719-1732
A tunnel diode non-linear transmission line has been investigated for second and third harmonic generation purposes. Design criteria are given and performance predictions have been obtained simulating the single diode behavior by means of a polynomial expression. An optimization of the non-linear transmission line as a harmonic generator has been obtained as a function of the number of diodes, their separation distances and the bias voltage. 相似文献
108.
Giancarlo Baldi Agostino Gianetto Silvio Sicardi Vito Specchia Italo Mazzarino 《加拿大化工杂志》1985,63(1):62-66
The interpretation of results of a chemical reaction carried out in a trickle bed reactor is not immediate when the key reactants are volatile; in fact some authors state that the overall conversion rate increases at very low liquid flow rates, i.e. when the catalyst is unevenly wetted. In these conditions, the reactants may penetrate inside the catalyst pellets directly through the “dry” zones; therefore the mass transfer resistance is diminished and the conversion rate can be increased. To investigate this phenomenon tests on the catalytic oxidation of ethyl alcohol dissolved in water were performed at different operating conditions in a trickle bed reactor. An interpretation of the results was tried by using two different models based on partially wetted particles. This approach considers both the cases in which “dry” zones are active or not for mass transfer and mass transfer rates are affected or not by the chemical reaction. 相似文献
109.
Giancarlo Cantarelli 《Dynamical Systems: An International Journal》1993,8(4):253-258
In this paper we find new first integrals of motion for a large class of nonlinear conservative gyroscopic mechanical systems. By means of the known first integrals, utilizing the classical Chetayev (1961) method, we construct a positive-definite first integral which ensures the stability of the equilibrium. 相似文献
110.
Finite-Element Approach to the Erosion and Transport of Fine Particles in Granular Soils 总被引:2,自引:0,他引:2
The increase of the water table level presently occurring in the city of Milan led to some leakage of groundwater in underground facilities and subway tunnels. These structures, in fact, were completed about three decades ago when the water table was deeply located. To locally lower the ground water, and to eliminate or limit its flow towards the submerged openings, a series of pumping wells was placed in their vicinity. This provision, however, could lead to possible erosion of the fine fraction of the granular soil and to consequent settlements of nearby buildings. To investigate this phenomenon a finite-element approach has been developed for the analysis of the erosion and transport of the fine particles of granular soils subjected to a seepage flow. First, the continuity equation governing the problem and its finite-element formulation are discussed. Then, on the basis of the results of erosion tests presented in the literature, a law is derived that accounts for the nonlinear relationship between the total amount of eroded material, for time tending to infinity, and the velocity of seepage. Finally, this law is applied to the solution of one- and two-dimensional test examples, and some conclusions are drawn on the limits of the developed numerical model and on its possible improvement. 相似文献