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81.
F. Petroni M. Serva 《The European Physical Journal B - Condensed Matter and Complex Systems》2006,51(4):601-608
The present study shows how the information on `hidden' market variables effects optimal investment strategies. We take the
point of view of two investors, one who has access to the hidden variables and one who only knows the quotes of a given asset.
Following Kelly's theory on investment strategies, the Shannon information and the doubling investment rate are quantified
for both investors. Thanks to his privileged knowledge, the first investor can follow a better investment strategy. Nevertheless,
the second investor can extract some of the hidden information looking at the past history of the asset variable. Unfortunately,
due to the complexity of his strategy, this investor will have computational difficulties when he tries to apply it. He will
than follow a simplified strategy, based only on the average sign of the last l quotes of the asset. This results have been
tested with some Monte Carlo simulations. 相似文献
82.
S. L. G. Petroni M. A. F. Pires C. S. Munita 《Journal of Radioanalytical and Nuclear Chemistry》2004,259(2):239-243
In this work copper adsorption by peat was studied using 64Cu as tracer considering kinetic and thermodynamic aspects of the process. The study was carried out in agitated batch experiments
with copper ion solutions with different initial concentrations at pH 4.5. Adsorption isotherms determined from equilibrium
experiments by fitting experimental data to the Langmuir equation showed good correlations. Data obtained from kinetics experiments
were fitted to a pseudo-second order model and also in this case a good correlation was obtained. Some parameters calculated
from these studies such as rate constant or peat sorption capacity can be used in the development of a waste treatment process
based on peat adsorption in batch or in column. The use of the 64Cu radiotracer is presented as a simple, rapid and efficient technique to assess the copper adsorption by the peat.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
83.
84.
Alves GA Amato S Anjos JC Appel JA Astorga J Bracker SB Cremaldi LM Dagenhart WD Darling CL Dixon RL Errede D Fenker HC Gay C Green DR Jedicke R Karchin PE Kennedy C Kwan S Lueking LH de Mello Neto JR Metheny J Milburn RH de Miranda JM da Motta Filho H Napier A Passmore D Rafatian A dos Reis AC Ross WR Santoro AF Sheaff M Souza MH Spalding WJ Stoughton C Streetman ME Summers DJ Takach SF Wallace A Wu Z 《Physical review letters》1996,77(12):2392-2395
85.
86.
87.
LL Handley R Azcón Ruiz Lozano JM CM Scrimgeour 《Rapid communications in mass spectrometry : RCM》1999,13(13):1320-1324
It has long been evident that plant (15)N chiefly reflects the processes which fractionate (15)N/(14)N rather than the (15)N of plant N source(s). It has emerged recently that one of the most important fractionating processes contributing to the whole plant (15)N is the presence/absence, type or species of mycorrhiza, especially when interacting with nutrient deficiency. Ecto- and ericoid mycorrhizas are frequently associated with (15)N-depleted foliar (15)N, commonly as low as -12 per thousand. As shown by the present study, plants having no mycorrhiza, or those infected with various species of arbuscular mycorrhiza (AM)-forming fungi, interact with varying concentrations of soil nitrogen [N] and moisture to enrich plant (15)N by as much as 3.5 per thousand. Hence the lack of a mycorrhiza, or variation in the species of AM-forming fungal associations, can account for about 25% of the usually reported variations of foliar (15)N found in field situations and do so by (15)N enrichment rather than depletion. Copyright 1999 John Wiley & Sons, Ltd. 相似文献
88.
A recent experiment [1] shows evidence for strong superluminal group and energy propagation, albeit not for superluminal signal velocity, in light pulses. A few remarks are in order about its implications on the quantum theory of light. 相似文献
89.
90.
Letizia Modeo Giovanna Rosati Ilaria Andreoli Simone Gabrielli Franco Verni Giulio Petroni 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2006,82(9):359-374
In the present paper we redescribe the ciliate Chattonidium setense Villeneuve 1937 combining morphological observations (live, stained, scanning, and transmission electron microscope) with behavioral notes and molecular data. Ultrastructural analysis revealed remarkable similarities between Chattonidium and representative members of the class Heterotrichea in cortical structure and cytoplasmic organization. The most similar genus for these aspects appears to be Condylostoma. To verify this relatedness, 18S rRNA genes from Chattonidium and from one Condylostoma species were sequenced. Phylogenetic analysis indicates Chattonidium belongs to the class Heterotrichea defined according to the modern taxonomy, and confirms its relatedness with Condylostoma already hypothesized by Villeneuve-Brachon (1940). The presence of the aboral cavity complex, a unique feature never described in other ciliates, and its peculiar organization revealed by ultrastructural analysis fully justify, in our opinion, the maintenance of Chattonidium in the separate family Chattonidiidae, established by Villeneuve-Brachon in 1940. 相似文献