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671.
Clara Baldoli Luigi Falciola Stefano Maiorana Patrizia Mussini Clara Rigamonti 《Journal of organometallic chemistry》2004,689(25):4791-4802
A new chiral ferrocene-labelled tyrosine PNA monomer 1 has been synthesised in good yield in both racemic and enantiomerically pure forms. It is suitable for insertion in various positions of PNA oligomers, a possibility that has been preliminarily demonstrated by synthesising the dimer 16. Moreover, in view of possible applications to nucleic acid detection, a preliminary voltammetric investigation on the electrochemical activity of monomer 1 and its synthetic precursors has been carried out in DMF. It appears that, despite the bulkiness of the PNA monomer backbone, its insertion on the ferrocene group only moderately lowers the latter’s diffusion coefficients and peak currents, thus affording voltammetric detection limits in the order of 10−6-10−7 M. 相似文献
672.
673.
Riassunto Si prova la rigidità di una certa classe di algebre integre di Cohen-Macaulay.
Lavoro svolto nell'ambito del G.N.S.A.G.A., sez. n. 3, del C.N.R. 相似文献
Summary We prove the rigidity of a certain class of algebras which are Cohen-Macaulay integral domains.
Lavoro svolto nell'ambito del G.N.S.A.G.A., sez. n. 3, del C.N.R. 相似文献
674.
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676.
Alessandro Lupi Maria Patamia Ingeborg Grgurina Rinaldo Marini Bettolo Ornella Di Leo Patrizia Gioia Simonetta Autnaroli 《Helvetica chimica acta》1984,67(8):2261-2263
A biogenetic-type total synthesis of(±)-2-deoxystemodinone ( 1 ), by solvolytic rearrangement of the 1-methyl[2.2.2]oct-2-yl methanesulphonate 4 , is described. 相似文献
677.
Francesca Caramia Caterina Mainero Francesca Gragnani Emanuele Tinelli Marco Fiorelli Vanessa Ceschin Patrizia Pantano Elisabetta Bucci Veronica Barra Luigi Bozzao Giovanni Antonini 《Magnetic resonance imaging》2010
Myotonic dystrophy type 1 (DM1) is a multisystemic disease involving multiple organ systems including central nervous system (CNS) and muscles. Few studies have focused on the central motor system in DM1, pointing to a subclinical abnormality in the CNS. The aim of our study was to investigate patterns of cerebral activation in DM1 during a motor task using functional MRI (fMRI). Fifteen DM1 patients, aged 20 to 59 years, and 15 controls of comparable age were scanned during a self-paced sequential finger-to-thumb opposition task of their dominant right hand. Functional MRI images were analyzed using SPM99. Patients underwent clinical and genetic assessment; all subjects underwent a conventional MR study. Myotonic dystrophy type 1 patients showed greater activation than controls in bilateral sensorimotor areas and inferior parietal lobules, basal ganglia and thalami, in the ipsilateral premotor area, insula and supplementary motor area (corrected P<.05). Analysis of the interaction between disease and age showed that correlation with age was significantly greater in patients than in controls in bilateral sensorimotor areas and in contralateral parietal areas. Other clinical and MR characteristics did not correlate with fMRI. Functional changes in DM1 may represent compensatory mechanisms such as reorganization and redistribution of functional networks to compensate for ultrastructural and neurochemical changes occurring as part of the accelerated aging process. 相似文献
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679.
Density functional calculations have been performed for small nickel clusters, Ni(n), Ni(n) (+), and Ni(n)(-) (n相似文献
680.
Patrizia Beraldi Antonio Violi Nadia Scordino Nicola Sorrentino 《Applied Mathematical Modelling》2011,35(8):3980-3990
This paper addresses the problem faced by a large electricity consumer in determining the optimal procurement plan over a short-term time horizon. The inherent complexity of the problem, due to its dynamic and stochastic nature, is dealt by means of the stochastic programming modeling framework. In particular, a two-stage problem is formulated with the aim of establishing the optimal amount of electricity to be purchased through bilateral contracts and in the Day-Ahead Electricity Market. Recourse actions are used to hedge against uncertainty related to future electricity prices and consumer’s needs. The optimal plan is defined so to minimize the overall cost and to control risk, which is measured in the form of violation of budget constraints. The stochastic model is dynamically solved in a rolling horizon fashion by iteratively considering more and more recent information and a planning horizon of decreasing length. Extensive numerical experiments have been carried out to assess the performance of the proposed dynamic decision approach. The results collected considering a real test case are very encouraging and provide evidence of the superiority of the approach also in comparison with other alternative procurement strategies. 相似文献