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101.
Warren G. Lewis Luke G. Green Flavio Grynszpan Zoran Radi Paul R. Carlier Palmer Taylor M. G. Finn K. Barry Sharpless 《Angewandte Chemie (International ed. in English)》2002,41(6):875-875
The cover picture shows the electric eel, Electrophorus electricus, a source for commercially available acetylcholinesterase. In an experiment described by K. B. Sharpless and M. G. Finn and co‐workers on pp. 1053–1057, a femtomolar inhibitor was assembled by the enzyme from a collection of building blocks containing azide and alkyne functional groups, shown floating in solution. The templated 1,3‐dipolar cycloaddition reaction, producing the inhibitor, is represented by the flare of light at the center of the image. 相似文献
102.
103.
Robert Marschinski Pietro Rossi Massimo Tavoni Flavio Cocco 《Annals of Operations Research》2007,151(1):223-239
Inspired by statistical physics, we present a probabilistic approach to portfolio selection. Instead of seeking the global
extremum of some chosen utility function, we reinterpret the latter as a probability distribution of ‘optimal’ portfolios,
and select the portfolio that is given by the mean value with respect to that distribution. Compared to the standard maximization
of expected utility, this approach has several attractive features. First, it significantly reduces the excessive sensitivity
to external parameters that often plague optimization procedures. Second, it mitigates the commonly observed concentration
on too few assets; and third, it provides a natural and consistent way to account for the incompleteness of information and
the aversion to uncertainty. Supportive empirical evidence is derived by using artificial data to simulate finite-sample behavior
and out-of-sample performance. 相似文献
104.
Moro G Bonati L Bruschi M Cosentino U De Gioia L Fantucci PC Pandini A Papaleo E Pitea D Saracino GA Zampella G 《Theoretical chemistry accounts》2007,117(5-6):723-741
Computational approaches based on Molecular Dynamics simulations, Quantum Mechanical methods and 3D Quantitative Structure-Activity
Relationships were employed by computational chemistry groups at the University of Milano-Bicocca to study biological processes
at the molecular level. The paper reports the methodologies adopted and the results obtained on Aryl hydrocarbon Receptor
and homologous PAS proteins mechanisms, the properties of prion protein peptides, the reaction pathway of hydrogenase and
peroxidase enzymes and the defibrillogenic activity of tetracyclines. 相似文献
105.
Flavio Granato Matteo Scampicchio Andrea Bianco Saverio Mannino Chiara Bertarelli Giuseppe Zerbi 《Electroanalysis》2008,20(12):1374-1377
A new approach for the fabrication of disposable electrochemical surfaces is presented. Conducting fibers have been produced by a two‐step process. Firstly, a fine web mat composed of nylon‐6 and ferric chloride fibers (with diameters of about 200 nm) were electrospun on a flat collector. Afterwards, the electrospun mat was exposed to pyrrole vapor under controlled dry atmosphere until each nylon thread was fully coated with a conducting polypyrrole layer. The conducting fiber mat was finally integrated within an electrochemical cell and used as a disposable sensor device. The suitability of the sensor was tested using phosphate and carbonate organic anions. The large scale fabrication of conducting tissue, in the form of a fine web of spun nanofibers, is relatively fast and inexpensive, and it paves the way to the build up of new disposable electrodes. 相似文献
106.
Angel A. Recio Despaigne Jeferson G. da Silva Ana Cerúlia M. do Carmo Flavio Sives Oscar E. Piro Eduardo E. Castellano Heloisa Beraldo 《Polyhedron》2009,28(17):3797-3803
In the present work 2-formylpyridine-para-chloro-phenyl hydrazone (H2FopClPh) and 2-formylpyridine-para-nitro-phenyl hydrazone (H2FopNO2Ph) were obtained, as well as their copper(II) and zinc(II) complexes [Cu(H2FopClPh)Cl2] (1), [Cu(2FopNO2Ph)Cl] (2), [Zn(H2FopClPh)Cl2] (3) and [Zn(H2FopNO2Ph)Cl2] (4). Upon re-crystallization in DMSO:acetone conversion of 2 into [Cu(2FopNO2Ph)Cl(DMSO)] (2a) and of 4 into [Zn(2FopNO2Ph)Cl(DMSO)] (4a) occurred. The crystal structures of 1, 2a, 3 and 4a were determined. 相似文献
107.
Flavio Bonetti Gian-Carlo Rota Domenico Senato Antonietta M. Venezia 《Studies in Applied Mathematics》1992,86(1):1-29
This paper examines surface gravity waves in a shallow channel with periodic or random bottom irregularities. Three types of bottom topography are distinguished, allowing a simplification of the basic shallow-water-wave equations. For two of them, asymptotic equations of the Korteveg-de Vries type are derived (the third type has been considered earlier by other authors). 相似文献
108.
109.
110.
Santabarbara S Cazzalini I Rivadossi A Garlaschi FM Zucchelli G Jennings RC 《Photochemistry and photobiology》2002,75(6):613-618
In the present study the analysis of the relation between the excited state population in the photosystem II (PSII) antenna and photoinactivation has been extended from an in vitro system, isolated thylakoids, to an in vivo system, Chlamydomonas reinhardtii cells. The results indicate that the excited state quenching by an added singlet quencher induces maximal protection against photoinhibition of about 30% of that expected on the basis of the observed light intensity-treatment time reciprocity rule. Similar results, obtained previously with thylakoids, have been interpreted in terms of damaged or incorrectly assembled complexes that play an important role in photoinhibition in the thylakoid membranes (Santabarbara, S., K. Neverov, F. M. Garlaschi, G. Zucchelli and R. C. Jennings [2001] Involvement of uncoupled antenna chlorophylls in photoinhibition in thylakoids. FEBS Lett. 491, 109-113.). In an attempt to better define this aspect, the photoinhibition action spectra were determined for mutant barley thylakoids, lacking the chlorophyll (Chl) a-b complexes of the outer antenna, and for its wild type. The results indicate that in both systems the action spectra are significantly blueshifted (2-4 nm) and are broader than the PSII absorption in the membranes. These data are interpreted in terms of a heterogeneous population of outer and inner antenna pigment-protein complexes that contain significant levels of uncoupled Chl. 相似文献